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Sample records for process flow diagram

  1. TEP process flow diagram

    Energy Technology Data Exchange (ETDEWEB)

    Wilms, R Scott [Los Alamos National Laboratory; Carlson, Bryan [Los Alamos National Laboratory; Coons, James [Los Alamos National Laboratory; Kubic, William [Los Alamos National Laboratory

    2008-01-01

    This presentation describes the development of the proposed Process Flow Diagram (PFD) for the Tokamak Exhaust Processing System (TEP) of ITER. A brief review of design efforts leading up to the PFD is followed by a description of the hydrogen-like, air-like, and waterlike processes. Two new design values are described; the mostcommon and most-demanding design values. The proposed PFD is shown to meet specifications under the most-common and mostdemanding design values.

  2. Fuel Retrieval System Process Flow Diagrams Mass Balance Calculations for K West Basin

    Energy Technology Data Exchange (ETDEWEB)

    REED, A.V.

    2000-01-03

    This calculation justifies the numbers used for the material balance on the process flow diagrams for the KW Basin Fuel Retrieval Subproject. The purpose of these calculations is to develop the material balances that are documented in the Fuel Retrieval System (FRS) Process Flow Diagrams for future reference. The attached mass calculations were prepared in support of revising the fuel retrieval system process flow diagrams for the 105K West Basin. The calculations refer to diagram H-1-81164.

  3. Spent Nuclear Fuel (SNF) Project Canister Storage Building (CSB) Process Flow Diagram Mass Balance Calculations

    Energy Technology Data Exchange (ETDEWEB)

    KLEM, M.J.

    2000-05-11

    The purpose of these calculations is to develop the material balances for documentation of the Canister Storage Building (CSB) Process Flow Diagram (PFD) and future reference. The attached mass balances were prepared to support revision two of the PFD for the CSB. The calculations refer to diagram H-2-825869.

  4. Spent Nuclear Fuel (SNF) Project Canister Storage Building (CSB) Process Flow Diagram Mass Balance Calculations

    International Nuclear Information System (INIS)

    The purpose of these calculations is to develop the material balances for documentation of the Canister Storage Building (CSB) Process Flow Diagram (PFD) and future reference. The attached mass balances were prepared to support revision two of the PFD for the CSB. The calculations refer to diagram H-2-825869

  5. Physiology Flow-Diagram Models

    Science.gov (United States)

    PhD Sandra J Bruner (Polk Community College Biology)

    2005-10-04

    A set of physiology flow-diagrams for the cardiovascular system, cardiac auto-rhythmic cell, cardiac contractile cell, respiratory system, coagulation/hemostasis, digestive system, excretion, and autonomic nervous system. These flow-diagrams show cause-and-effect markup and have accompanying tutorials.

  6. Architecture flow diagrams under teamwork reg sign

    Energy Technology Data Exchange (ETDEWEB)

    Nicinski, T.

    1992-02-01

    The Teamwork CASE tool allows Data Flow Diagrams (DFDs) to be maintained for structured analysis. Fermilab has extended teamwork under UNIX{trademark} to permit Hatley and Pirbhai Architecture Flow Diagrams (AFDs) to be associated with DFDs and subsequently maintained. This extension, called TWKAFD, allows a user to open an AFD, graphically edit it, and replace it into a TWKAFD maintained library. Other aspects of Hatley and Pirbhai's methodology are supported. This paper presents a quick tutorial on Architecture Diagrams. It then describes the user's view of TWKAFD, the experience incorporating it into teamwork, and the successes with using the Architecture Diagram methodology along with the shortcomings of using the teamwork/TWKAFD tool. 8 refs.

  7. Shape Diagram of Vesicles in Poiseuille Flow

    Science.gov (United States)

    Coupier, Gwennou; Farutin, Alexander; Minetti, Christophe; Podgorski, Thomas; Misbah, Chaouqi

    2012-04-01

    Soft bodies flowing in a channel often exhibit parachutelike shapes usually attributed to an increase of hydrodynamic constraint (viscous stress and/or confinement). We show that the presence of a fluid membrane leads to the reverse phenomenon and build a phase diagram of shapes—which are classified as bullet, croissant, and parachute—in channels of varying aspect ratio. Unexpectedly, shapes are relatively wider in the narrowest direction of the channel. We highlight the role of flow patterns on the membrane in this response to the asymmetry of stress distribution.

  8. Shape diagram of vesicles in Poiseuille flow

    CERN Document Server

    Coupier, Gwennou; Minetti, Christophe; Podgorski, Thomas; Misbah, Chaouqi

    2012-01-01

    Soft bodies flowing in a channel often exhibit parachute-like shapes usually attributed to an increase of hydrodynamic constraint (viscous stress and/or confinement). We show that the presence of a fluid membrane leads to the reverse phenomenon and build a phase diagram of shapes --- which are classified as bullet, croissant and parachute --- in channels of varying aspect ratio. Unexpectedly, shapes are relatively wider in the narrowest direction of the channel. We highlight the role of flow patterns on the membrane in this response to the asymmetry of stress distribution.

  9. Mean-Curvature Flow of Voronoi Diagrams

    Science.gov (United States)

    Elsey, Matt; Slep?ev, Dejan

    2015-02-01

    We study the evolution of grain boundary networks by the mean-curvature flow under the restriction that the networks are Voronoi diagrams for a set of points. For such evolution we prove a rigorous universal upper bound on the coarsening rate. The rate agrees with the rate predicted for the evolution by mean-curvature flow of the general grain boundary networks, namely that the typical grain area grows linearly in time. We perform a numerical simulation which provides evidence that the dynamics achieves the rate of coarsening that agrees with the upper bound in terms of scaling.

  10. Implementation of a knowledge-based methodology in a decision support system for the design of suitable wastewater treatment process flow diagrams.

    Science.gov (United States)

    Garrido-Baserba, Manel; Reif, Rubén; Hernández, Francesc; Poch, Manel

    2012-12-15

    In light of rapid global change, the demand for wastewater treatment is increasing rapidly and will continue to do so in the near future. Wastewater management is a complex puzzle for which the proper pieces must be combined to achieve the desired solution, requiring the simultaneous consideration of technical, economic, social and environmental issues. In this context, a knowledge-based methodology (KBM) for the conceptual design of wastewater treatment plant (WWTP) process flow diagrams (PFDs) and its application for two scenarios is presented in this paper. The core of the KBM is composed of two knowledge bases (KBs). The first, a specification knowledge base (S-KB), summarizes the main features of the different treatment technologies: pollutants removal efficiency, operational costs and technical reliability. The second, a compatibility knowledge base (C-KB), contains information about the different interactions amongst the treatment technologies and determines their degree of compatibility. The proposed methodology is based on a decision hierarchy that uses the information contained in both KBs to generate all possible WWTP configurations, screening and selecting appropriate configurations based on user-specified requirements and scenario characteristics. The design of the most adequate treatment train for small and medium sized wastewater treatment plants (2000 and 50,000 p.e. respectively) according to different restrictions (space constraints, operation simplicity and cost optimization) was the example in order to show the usefulness of the KBM. PMID:22982697

  11. Planar quark diagrams and binary spin processes

    International Nuclear Information System (INIS)

    Contributions of planar diagrams to the binary scattering processes are analyzed. The analysis is based on the predictions of quark-gluon picture of strong interactions for the coupling of reggeons with quarks as well as on the SU(6)-classification of hadrons. The dependence of contributions of nonplanar corrections on spins and quark composition of interacting particles is discussed

  12. Introducing the Circular Flow Diagram to Business Students

    Science.gov (United States)

    Daraban, Bogdan

    2010-01-01

    The circular flow of income diagram is a simplified representation of the functioning of a free-market economic system. It illustrates how businesses interact with the other economic participants within the key macroeconomic markets that coordinate the flow of income through the national economy. Therefore, it can provide students of business with…

  13. Architecture flow diagrams under teamwork{reg_sign}

    Energy Technology Data Exchange (ETDEWEB)

    Nicinski, T.

    1992-02-01

    The Teamwork CASE tool allows Data Flow Diagrams (DFDs) to be maintained for structured analysis. Fermilab has extended teamwork under UNIX{trademark} to permit Hatley and Pirbhai Architecture Flow Diagrams (AFDs) to be associated with DFDs and subsequently maintained. This extension, called TWKAFD, allows a user to open an AFD, graphically edit it, and replace it into a TWKAFD maintained library. Other aspects of Hatley and Pirbhai`s methodology are supported. This paper presents a quick tutorial on Architecture Diagrams. It then describes the user`s view of TWKAFD, the experience incorporating it into teamwork, and the successes with using the Architecture Diagram methodology along with the shortcomings of using the teamwork/TWKAFD tool. 8 refs.

  14. Concept and development of information flow diagram for literature survey

    International Nuclear Information System (INIS)

    The Information Flow Diagram for Literature Survey (IFDLS) has been developed to manage information and procedure in the literature survey phase of the PTAs selection process. It is a tool utilizing information technology, which can organize, analyze, and evaluate information from literature survey and manage their process systematically. IFDLS is able to show the flow of information and data, and the history of information management processing. Information coverage and quality is not homogenous throughout the country and, in some areas, there may not even be sufficient data available to be able to reach a judgment on conformity with the site-specific evaluation factors (SSEF). Literature surveys could only be conducted on a volunteer area before it is nominated as a PIA. However, the absence of information on any factor mentioned will not constitute disqualification of the area. On the contrary, an attempt to compare these sites with analogous areas in Japan will be done to assemble sufficient data and consequently make a decision on whether to proceed further. The application of IFDLS to literature survey phase of the PIA selection process is being proposed. The concept, construction, application and evolution of IFDLS towards application phase on a trial basis are discussed. (authors)

  15. Derivation of a Fundamental Diagram for Urban Traffic Flow

    CERN Document Server

    Helbing, Dirk

    2008-01-01

    Despite the importance of urban traffic flows, there are only a few theoretical approaches to determine fundamental relationships between macroscopic traffic variables such as the traffic density, the utilization, the average velocity, and the travel time. In the past, empirical measurements have primarily been described by fit functions. Here, we derive expected fundamental relationships from a model of traffic flows at intersections, which suggest that the recently measured fundamental diagrams for urban flows can be systematically understood. In particular, this allows one to derive the average travel time and the average vehicle speed as a function of the utilization and/or the average number of delayed vehicles.

  16. The Exergy of Lift and Aircraft Exergy Flow Diagrams

    Directory of Open Access Journals (Sweden)

    Richard A. Gaggioli

    2003-12-01

    Full Text Available Aside from incidental, auxiliary loads, in level flight the principal load on the aircraft propulsion engine is the power required to provide the continuous lift. To construct an exergy flow diagram for an aircraft – for example, for the purpose of pinpointing inefficiencies and for costing – an expression is needed for the exergy delivered to and by the wings. That is, an expression is needed for the exergy of lift. The purpose of this paper is to present an expression developed for the exergy of lift, applicable not only in level flight but in other modes of flight as well. In order to illustrate the relevance of exergy of lift, two exergy flow diagrams are presented for a light aircraft, one for level flight, and one for climb.

  17. The Exergy of Lift and Aircraft Exergy Flow Diagrams

    OpenAIRE

    Gaggioli, Richard A.; David M Paulus, Jr

    2003-01-01

    Aside from incidental, auxiliary loads, in level flight the principal load on the aircraft propulsion engine is the power required to provide the continuous lift. To construct an exergy flow diagram for an aircraft – for example, for the purpose of pinpointing inefficiencies and for costing – an expression is needed for the exergy delivered to and by the wings. That is, an expression is needed for the exergy of lift. The purpose of this paper is to present an expression de...

  18. Flow phase diagrams for concentration-coupled shear banding.

    Science.gov (United States)

    Fielding, S M; Olmsted, P D

    2003-05-01

    After surveying the experimental evidence for concentration coupling in the shear banding of wormlike micellar surfactant systems, we present flow phase diagrams spanned by shear stress Sigma (or strain rate gamma) and concentration, calculated within the two-fluid, non-local Johnson-Segalman (d-JS-phi) model. We also give results for the macroscopic flow curves Sigma(gamma,phi) for a range of (average) concentrations phi. For any concentration that is high enough to give shear banding, the flow curve shows the usual non-analytic kink at the onset of banding, followed by a coexistence "plateau" that slopes upwards, dSigma/dgamma>0. As the concentration is reduced, the width of the coexistence regime diminishes and eventually terminates at a non-equilibrium critical point [Sigmac,phic,gammac]. We outline the way in which the flow phase diagram can be reconstructed from a family of such flow curves, Sigma(gamma,phi), measured for several different values of phi. This reconstruction could be used to check new measurements of concentration differences between the coexisting bands. Our d-JS-phi model contains two different spatial gradient terms that describe the interface between the shear bands. The first is in the viscoelastic constitutive equation, with a characteristic (mesh) length l. The second is in the (generalised) Cahn-Hilliard equation, with the characteristic length xi for equilibrium concentration-fluctuations. We show that the phase diagrams (and so also the flow curves) depend on the ratio r congruent with l/xi, with loss of unique state selection at r=0. We also give results for the full shear-banded profiles, and study the divergence of the interfacial width (relative to l and xi) at the critical point. PMID:15015089

  19. Flow phase diagrams for concentration-coupled shear banding

    CERN Document Server

    Fielding, S M; Fielding, Suzanne M; Olmsted, Peter D

    2003-01-01

    After surveying the experimental evidence for concentration coupling in the shear banding of wormlike micellar surfactant solutions, we present flow phase diagrams spanned by shear stress (or strain-rate) and concentration in the two-fluid, non-local Johnson-Segalman (d-JS-phi) model. We also present macroscopic flow curves for a range of (average) concentrations. For any concentration high enough to give shear banding, the flow curve shows the usual non-analytic kink at the onset of banding, followed by a coexistence ``plateau'' that slopes upwards. As the concentration is reduced, the width of the coexistence regime diminishes, then terminates at a non-equilibrium critical point. We outline the way in which the flow phase diagram can be reconstructed from a family of such flow curves measured for several different average concentrations. This reconstruction could be used to check new measurements of concentration differences between the coexisting bands. Our d-JS-phi model contains two spatial gradient term...

  20. Andreas Acrivos Dissertation Prize Lecture: Stability of inviscid flows from bifurcation diagrams exploiting a variational argument

    Science.gov (United States)

    Luzzatto-Fegiz, Paolo

    2011-11-01

    Steady fluid solutions play a special role in the dynamics of a flow: stable states may be realized in practice, while unstable ones may act as attractors. Unfortunately, determining stability is often a process far more laborious than finding steady states; indeed, even for simple vortex or wave flows, stability properties have often been the subject of debate. We consider here a stability idea originating with Lord Kelvin (1876), which involves using the second variation of the energy, 2?E, to establish bounds on a perturbation. However, for numerically obtained flows, computing 2?E explicitly is often not feasible. To circumvent this issue, Saffman & Szeto (1980) proposed an argument linking changes in 2?E to turning points in a bifurcation diagram, for families of steady flows. Later work has shown that this argument is unreliable; the two key issues are associated with the absence of a formal turning-point theory, and with the inability to detect bifurcations (Dritschel 1995, and references therein). In this work, we build on ideas from bifurcation theory, and link turning points in a velocity-impulse diagram to changes in 2?E; in addition, this diagram delivers the direction of the change of 2?E, thereby providing information as to whether stability is gained or lost. To detect hidden solution branches, we introduce to these fluid problems concepts from imperfection theory. The resulting approach, involving ``imperfect velocity-impulse" diagrams, leads us to new and surprising results for a wide range of fundamental vortex and wave flows; we mention here the calculation of the first steady vortices without any symmetry, and the uncovering of the complete solution structure for vortex pairs. In addition, we find precise agreement with available results from linear stability analysis.

  1. Feynchois: System For Automating The Process Of Feynman Diagram Generation

    CERN Document Server

    Choi, C

    2004-01-01

    We have developed a DTD (Document Type Definition) for an XML (Extensible Markup Language) document for describing Feynman rules of quantum field theoretical models—the document is called FeynPage. A FeynPage can be any XML document that conforms to the FeynPage DTD. A FeynPage can be understood by a human or a computer program that is aware of the FeynPage DTD. We have also developed a Feynman diagram generator, which has been named FeynChois. It provides a user with a full GUI (Graphical User Interface) environment. More importantly, FeynChois knows how to read FeynPage. When FeynChois is asked by a user to generate diagrams, it will first look up the rules in the FeynPage; then, it will generate diagrams according to the rules for any process specified by the user. If the Feynman rules in a FeynPage are modified, FeynChois will generate diagrams according to the modified rules. What FeynChois generates are actually Java™ objects that represent Feynman diagrams. These objects are graphi...

  2. Improving The Decisional Process By Using UML Diagrams

    Directory of Open Access Journals (Sweden)

    Udrica Mioara

    2012-06-01

    Full Text Available In the last years, the world has moved from predominantly industrial society to information society, governed by a new set of rules, which allows access to digital technologies, processing, storage and transmission of information. Organizations include in their decisional process Business Intelligence components, which help the decision-makers to establish the conditions of financial equilibrium, to highlight weaknesses and strengths, to make predictions.Particularly, Unified Modelling Language (UML, as a formal and standardized language, allows the control of the system’s complexity, shows different but complementary views of the organization and ensures independence towards the implementation language and the domain of application. This article aims to show the way UML diagrams are used as support in a decisional process for a hotel company. UML diagrams designed help decisionmakers to analysis and discover the causes, to design and simulation of possible scenarios, to implement and measuring the results.

  3. Scale setting in QCD and the momentum flow in Feynman diagrams

    CERN Document Server

    Neubert, M

    1995-01-01

    We present a formalism to evaluate QCD diagrams with a single virtual gluon using a running coupling constant at the vertices. This method, which corresponds to an all-order resummation of certain terms in a perturbative series, provides a description of the momentum flow through the gluon propagator. It can be viewed as a generalization of the scale-setting prescription of Brodsky, Lepage and Mackenzie to all orders in perturbation theory. In particular, the approach can be used to investigate why in some cases the ``typical'' momenta in a loop diagram are different from the ``natural'' scale of the process. Moreover, it offers an intuitive understanding of the appearance of infrared renormalons in perturbation theory, their connection to the rate of convergence of a perturbative series, and the necessity to separate short- and long-distance contributions. Several applications to one- and two-scale problems are discussed in detail.

  4. Thermodynamic methodology of energy-flow framework diagram for technical energy systems

    International Nuclear Information System (INIS)

    This paper presents a novel thermodynamic analysis tool, the energy-flow framework diagram (EFD), and proposes a new method called the EFD graphic analysis method. It is a visual method of energy analysis and integration and is fairly convenient to analyze variety of complicated information, with the aim at bring forward a creative energy-saving system. It is proved that the new method is effective and useful through an application study on a 560 kt/a methanol synthesis process by means of the EFD and the revelatory criteria

  5. Phase diagram of the ABC model with nonconserving processes

    International Nuclear Information System (INIS)

    The three species ABC model of driven particles on a ring is generalized to include vacancies and particle-nonconserving processes. The model exhibits phase separation at high densities. For equal average densities of the three species, it is shown that although the dynamics is local, it obeys detailed balance with respect to a Hamiltonian with long-range interactions, yielding a nonadditive free energy. The phase diagrams of the conserving and nonconserving models, corresponding to the canonical and grand-canonical ensembles, respectively, are calculated in the thermodynamic limit. Both models exhibit a transition from a homogeneous to a phase-separated state, although the phase diagrams are shown to differ from each other. This conforms with the expected inequivalence of ensembles in equilibrium systems with long-range interactions. These results are based on a stability analysis of the homogeneous phase and exact solution of the continuum equations of the models. They are supported by Monte Carlo simulations. This study may serve as a useful starting point for analyzing the phase diagram for unequal densities, where detailed balance is not satisfied and thus a Hamiltonian cannot be defined

  6. Mizunami Underground Research Laboratory project. Preparation of geosynthesis data flow diagram (Construction phase)

    International Nuclear Information System (INIS)

    Japan Atomic Energy Agency (JAEA) at Tono Geoscience Center (TGC) is pursuing a geoscientific research and development project, namely the Mizunami Underground Research Laboratory (MIU) project, in crystalline rock environment in order to construct scientific and technological basis for geological disposal of High-level Radioactive Waste (HLW). The MIU project is planned in three overlapping phases ; Surface-based Investigation Phase (Phase I), Construction Phase (Phase II) and Operation Phase (Phase III). Currently, the project is under the Construction Phase and the Operation Phase. In Phase II, adequacy of geological environment models established in Phase I is evaluated by using the data accumulated during Phase II. Based on the evaluation results, applicability and feasibility assessment of various elemental technologies adopted to characterize geological environment in Phase I will be evaluated. The various elemental technologies include planning method, investigation method and modeling method. Furthermore, from a design, construction and safety assessment point of view, a series of evaluation procedures are organized and Geosynthesis Data Flow Diagram is established. This data flow diagram is the integrated data flow from investigation through modeling and analysis. It proposes the rational combinations of investigation items which make the investigation results reflect the safety assessment and designing. In this sense, Geosynthesis Data Flow Diagram indicates the rational framework, from “investigation” to “modeling and analysis”, for achieving individual goals and tasks. This report summarizes the Geosynthesis Data Flow Diagram optimized during Phase II investigation. The Geosynthesis Data Flow Diagram will be revised based on the research progress. (author)

  7. Lifting business process diagrams to 2.5 dimensions

    Science.gov (United States)

    Effinger, Philip; Spielmann, Johannes

    2010-01-01

    In this work, we describe our visualization approach for business processes using 2.5 dimensional techniques (2.5D). The idea of 2.5D is to add the concept of layering to a two dimensional (2D) visualization. The layers are arranged in a three-dimensional display space. For the modeling of the business processes, we use the Business Process Modeling Notation (BPMN). The benefit of connecting BPMN with a 2.5D visualization is not only to obtain a more abstract view on the business process models but also to develop layering criteria that eventually increase readability of the BPMN model compared to 2D. We present a 2.5D Navigator for BPMN models that offers different perspectives for visualization. Therefore we also develop BPMN specific perspectives. The 2.5D Navigator combines the 2.5D approach with perspectives and allows free navigation in the three dimensional display space. We also demonstrate our tool and libraries used for implementation of the visualizations. The underlying general framework for 2.5D visualizations is explored and presented in a fashion that it can easily be used for different applications. Finally, an evaluation of our navigation tool demonstrates that we can achieve satisfying and aesthetic displays of diagrams stating BPMN models in 2.5D-visualizations.

  8. Emergence of bistable states and phase diagrams of traffic flow at an unsignalized intersection

    Science.gov (United States)

    Li, Qi-Lang; Jiang, Rui; Wang, Bing-Hong

    2015-02-01

    This paper studies phase diagrams of traffic states induced by the bottleneck of an unsignalized intersection which consists of two perpendicular one-lane roads. Parallel updates rules are employed for both roads. At the crossing point, in order to avoid colliding, the consideration of yield dynamics may be suitable herein. Different from previous studies, the deterministic Nagel and Schreckenberg model is adopted in this work. Based on theoretical analysis and computer simulations, the phase diagrams of traffic flow have been presented and the flow formulas in all regions have been derived in the phase diagram. The results of theoretical analysis are in good agreement with computer simulation ones. One finds an interesting phenomenon: there exist bistable states in some regions of the phase diagrams.

  9. XML transformation flow processing

    OpenAIRE

    Euzenat, Je?ro?me; Tardif, Laurent

    2001-01-01

    The XSLT language is both complex to use in simple cases (like tag renaming or element hiding) and restricted in complex ones (requiring the processing of multiple stylesheets with complex information flows). We propose a framework improving on XSLT. It provides simple-to-use and easy-to-analyze macros for the basic common transformation tasks. It provides a superstructure for composing multiple stylesheets, with multiple input and output documents, in ways that are not accessible within XSLT...

  10. Phase diagram of the symbiotic two-species contact process

    Science.gov (United States)

    de Oliveira, Marcelo Martins; Dickman, Ronald

    2014-09-01

    We study the two-species symbiotic contact process, recently proposed by de Oliveira, Santos, and Dickman [Phys. Rev. E 86, 011121 (2012), 10.1103/PhysRevE.86.011121]. In this model, each site of a lattice may be vacant or host single individuals of species A and/or B. Individuals at sites with both species present interact in a symbiotic manner, having a reduced death rate ? <1. Otherwise, the dynamics follows the rules of the basic contact process, with individuals reproducing to vacant neighbor sites at rate ? and dying at a rate of unity. We determine the full phase diagram in the ?-? plane in one and two dimensions by means of exact numerical quasistationary distributions, cluster approximations, and Monte Carlo simulations. We also study the effects of asymmetric creation rates and diffusion of individuals. In two dimensions, for sufficiently strong symbiosis (i.e., small ?), the absorbing-state phase transition becomes discontinuous for diffusion rates D within a certain range. We report preliminary results on the critical surface and tricritical line in the ?-?-D space. Our results raise the possibility that strongly symbiotic associations of mobile species may be vulnerable to sudden extinction under increasingly adverse conditions.

  11. Students' Ability to Solve Process-Diagram Problems in Secondary Biology Education

    Science.gov (United States)

    Kragten, Marco; Admiraal, Wilfried; Rijlaarsdam, Gert

    2015-01-01

    Process diagrams are important tools in biology for explaining processes such as protein synthesis, compound cycles and the like. The aim of the present study was to measure the ability to solve process-diagram problems in biology and its relationship with prior knowledge, spatial ability and working memory. For this purpose, we developed a test…

  12. Non-resonant diagrams in radiative four-fermion processes

    International Nuclear Information System (INIS)

    The complete tree level cross section for e+e-?e- anti ?eud? is computed and discussed in comparison with the cross sections for e+e-?e- anti ?eud and e+e-?udud. Event generators based on the GRACE package for the non-radiative and radiative case are presented. Special interest is brought to the effect of the non-resonant diagrams overlooked so far in other studies. Their contribution to the total cross section is presented for the LEP II energy range and for future linear colliders (?(s)=500GeV). Effects, at the W pair threshold, of order 3% (e- anti ?eu anti d) and 27% ( anti udu anti d) are reported. Similar behaviour for the radiative case is shown. At ?(s)=500GeV, the relative contribution of the non-resonant diagrams for the radiative channel reaches 42.5%. ((orig.))

  13. Phase diagrams of laser-processed nanoparticles of brass

    International Nuclear Information System (INIS)

    Nanoparticles of brass are prepared by ablation of a brass target in ethanol using radiation of a copper-vapor laser at various laser fluences. The nanoparticles are characterized by TEM and optical spectroscopy. The multipulse laser irradiation leads to formation both the nanoparticles in liquid and well-ordered micro-structures on a surface of a target. It is revealed that both the morphology and absorption spectra of brass nanoparticles depend on presence of the micro-structures. Nanoparticles with the various phase diagrams are formed from a flat brass surface and from the same surface with micro-structures. The results are compared with a model of phase diagrams, in which size and composition effects are taken into account

  14. On the effect of stochastic transition in the fundamental diagram of traffic flow

    CERN Document Server

    Siqueira, Adriano Francisco; Wu, Chen; Qian, Wei-Liang

    2014-01-01

    In this work, we propose an alternative stochastic model for the fundamental diagram of traffic flow with minimal number of parameters. Our approach is based on a mesoscopic viewpoint of the traffic system in terms of the dynamics of vehicle velocity transitions. A key feature of the present approach lies in its stochastic nature which makes it possible to describe not only the flow-concentration relation, the so-called fundamental diagram in traffic engineering, but also its variance -- an important ingredient in the observed data of traffic flow. It is shown that the model can be seen as a derivative of the Boltzmann equation when assuming a discrete velocity spectrum. The latter assumption significantly simplifies the mathematics and therefore, facilitates the study of its physical content through the analytic solutions. The model parameters are then adjusted to reproduce the observed traffic flow on the "23 de maio" highway in the Brazilian city of Sao Paulo, where both the fundamental diagram and its var...

  15. Merging Object and Process Diagrams for Business Information Modeling

    OpenAIRE

    Che?nais, Patrick

    2008-01-01

    While developing an information system for the University of Bern, we were faced with two major issues: managing software changes and adapting Business Information Models. Software techniques well-suited to software development teams exist, yet the models obtained are often too complex for the business user. We will first highlight the conceptual problems encountered while designing the Business Information Model. We will then propose merging class diagrams and business proc...

  16. Non-resonant diagrams in radiative four-fermion processes

    International Nuclear Information System (INIS)

    The complete tree level cross section for e+e- ? e-?-bareud-bar? is computed and discussed in comparison with the cross sections for e+e- ? e-V-bare u d-bar and e+e- ? u-bar d u d-bar. Event generators based on the GRACE package for the non-radiative and radiative case are presented. Special interest is brought to the effect of the non-resonant diagrams overlooked so far in other studies. Their contribution to the total cross section is presented for the LEP II energy range for future linear colliders (?s = 500 GeV). (author)

  17. Microsoft excel's automatic data processing and diagram drawing of RIA internal quality control parameters

    International Nuclear Information System (INIS)

    We did automatic data processing and diagram drawing of various parameters of RIA' s internal quality control (IQC)by the use of Microsoft Excel (ME). By use of AVERAGE and STDEV of ME, we got x-bar, s and CV%. With pearson, we got the serum quality control coefficients (r). Inputing the original data to diagram's self-definition item, the diagram was drawn automatically. By the use of logic judging, we got the quality control judging results with the status, timing and data of various quality control parameters. For the past four years, the ME data processing and diagram drawing as well as quality control judging have been showed to be accurate, convenient and correct. It was quick and easy to manage and the automatic computer processing of RIA's IQC was realized. Conclusion: the method is applicable to all types of RIA' s IQC. (authors)

  18. Development of the Functional Flow Block Diagram for the J-2X Rocket Engine System

    Science.gov (United States)

    White, Thomas; Stoller, Sandra L.; Greene, WIlliam D.; Christenson, Rick L.; Bowen, Barry C.

    2007-01-01

    The J-2X program calls for the upgrade of the Apollo-era Rocketdyne J-2 engine to higher power levels, using new materials and manufacturing techniques, and with more restrictive safety and reliability requirements than prior human-rated engines in NASA history. Such requirements demand a comprehensive systems engineering effort to ensure success. Pratt & Whitney Rocketdyne system engineers performed a functional analysis of the engine to establish the functional architecture. J-2X functions were captured in six major operational blocks. Each block was divided into sub-blocks or states. In each sub-block, functions necessary to perform each state were determined. A functional engine schematic consistent with the fidelity of the system model was defined for this analysis. The blocks, sub-blocks, and functions were sequentially numbered to differentiate the states in which the function were performed and to indicate the sequence of events. The Engine System was functionally partitioned, to provide separate and unique functional operators. Establishing unique functional operators as work output of the System Architecture process is novel in Liquid Propulsion Engine design. Each functional operator was described such that its unique functionality was identified. The decomposed functions were then allocated to the functional operators both of which were the inputs to the subsystem or component performance specifications. PWR also used a novel approach to identify and map the engine functional requirements to customer-specified functions. The final result was a comprehensive Functional Flow Block Diagram (FFBD) for the J-2X Engine System, decomposed to the component level and mapped to all functional requirements. This FFBD greatly facilitates component specification development, providing a well-defined trade space for functional trades at the subsystem and component level. It also provides a framework for function-based failure modes and effects analysis (FMEA), and a rigorous baseline for the functional architecture.

  19. Improving The Decisional Process By Using UML Diagrams

    OpenAIRE

    Udrica Mioara; Marius Iulian; Opri? Violeta Nicoleta; Ioni?? R?zvan Hora?iu

    2012-01-01

    In the last years, the world has moved from predominantly industrial society to information society, governed by a new set of rules, which allows access to digital technologies, processing, storage and transmission of information. Organizations include in their decisional process Business Intelligence components, which help the decision-makers to establish the conditions of financial equilibrium, to highlight weaknesses and strengths, to make predictions.Particularly, Unified Modelling Langua...

  20. Power diagrams and interaction processes for unions of discs

    DEFF Research Database (Denmark)

    MØller, Jesper; Helisova, Katerina

    2008-01-01

     We study a flexible class of finite-disc process models with interaction between the discs. We let U denote the random set given by the union of discs, and use for the disc process an exponential family density with the canonical sufficient statistic depending only on geometric properties of U such as the area, perimeter, Euler-Poincaré characteristic, and the number of holes. This includes the quermass-interaction process and the continuum random-cluster model as special cases. Viewing our model as a connected component Markov point process, and thereby establishing local and spatial Markov properties, becomes useful for handling the problem of edge effects when only U is observed within a bounded observation window. The power tessellation and its dual graph become major tools when establishing inclusion-exclusion formulae, formulae for computing geometric characteristics of U, and stability properties of the underlying disc process density. Algorithms for constructing the power tessellation of U and for simulating the disc process are discussed, and the software is made public available. Udgivelsesdato: JUN

  1. Control structures for flow process

    Directory of Open Access Journals (Sweden)

    Mircea Dul?u

    2011-12-01

    Full Text Available In the industrial domain, a large number of applications is covered by slow processes, including the flow, the pressure, the temperature and the level control. Each control system must be treated in steady and dynamic states and from the point of view of the possible technical solutions. Based on mathematical models of the processes and design calculations, PC programs allow simulation and the determination of the control system performances.The paper presents a part of an industrial process with classical control loops of flow and temperature. The mathematical model of the flow control process was deducted, the control structure, based on experimental criterions, was designed and the version witch ensure the imposed performances was chosen. Using Matlab, the robustness performances were studied.

  2. The organization of intrinsic computation: complexity-entropy diagrams and the diversity of natural information processing.

    Science.gov (United States)

    Feldman, David P; McTague, Carl S; Crutchfield, James P

    2008-12-01

    Intrinsic computation refers to how dynamical systems store, structure, and transform historical and spatial information. By graphing a measure of structural complexity against a measure of randomness, complexity-entropy diagrams display the different kinds of intrinsic computation across an entire class of systems. Here, we use complexity-entropy diagrams to analyze intrinsic computation in a broad array of deterministic nonlinear and linear stochastic processes, including maps of the interval, cellular automata, and Ising spin systems in one and two dimensions, Markov chains, and probabilistic minimal finite-state machines. Since complexity-entropy diagrams are a function only of observed configurations, they can be used to compare systems without reference to system coordinates or parameters. It has been known for some time that in special cases complexity-entropy diagrams reveal that high degrees of information processing are associated with phase transitions in the underlying process space, the so-called "edge of chaos." Generally, though, complexity-entropy diagrams differ substantially in character, demonstrating a genuine diversity of distinct kinds of intrinsic computation. PMID:19123616

  3. Phase Diagram and Breathing Dynamics of Red Blood Cell Motion in Shear Flow

    Science.gov (United States)

    Bagchi, Prosenjit; Yazdani, Alireza

    2011-11-01

    We present phase diagrams of red blood cell dynamics in shear flow using three-dimensional numerical simulations. By considering a wide range of shear rate and interior-to-exterior fluid viscosity ratio, it is shown that the cell dynamics is often more complex than the well-known tank-treading, tumbling and swinging motion, and is characterized by an extreme variation of the cell shape. We identify such complex shape dynamics as `breathing' dynamics. During the breathing motion, the cell either completely aligns with the flow direction and the membrane folds inward forming two cusps, or, it undergoes large swinging motion while deep, crater-like dimples periodically emerge and disappear. At lower bending rigidity, the breathing motion occurs over a wider range of shear rates, and is often characterized by the emergence of a quad-concave shape. The effect of the breathing dynamics on the tank-treading-to-tumbling transition is illustrated by detailed phase diagrams which appear to be more complex and richer than those of vesicles. In a remarkable departure from classical theory of nondeformable cells, we find that there exists a critical viscosity ratio below which the transition is dependent on shear rate only.

  4. Asymmetric simple exclusion process describing conflicting traffic flows

    CERN Document Server

    Foulaadvand, M Ebrahim

    2008-01-01

    We use the asymmetric simple exclusion process for describing vehicular traffic flow at the intersection of two streets. No traffic lights control the traffic flow. The approaching cars to the intersection point yield to each other to avoid collision. This yielding dynamics is model by implementing exclusion process to the intersection point of the two streets. Closed boundary condition is applied to the streets. We utilize both mean-field approach and extensive simulations to find the model characteristics. In particular, we obtain the fundamental diagrams and show that the effect of interaction between chains can be regarded as a dynamic impurity at the intersection point.

  5. Digital analysis and potato tissue image processing at the application of voronofs diagrams*

    Directory of Open Access Journals (Sweden)

    A. Guc

    1995-12-01

    Full Text Available In this paper image processing is presented from the point of view of obtaining cell wall image. We also proposed some measurement and analysis methods. Because of non-continuos character of plant structure, the authors applied Voronoi's diagrams. This model allows for application of some point co-ordinates and segment lengths only. Also Voronoi's diagrams make easier obtaining a few parameters important for geometrical properties of cell wall. Color microscope images have been converted from RGB system into HLS system which enabled to obtain information about the space configuration of point of objects being investigated and to identify structural elements.

  6. Display the CIE 1931 color chromaticity diagram with digital image processing

    Science.gov (United States)

    Zhao, Hong-Dong; Yao, Yi-Yang; Sun, Fei; Zhang, Qin; Yang, Xiao-Hui

    2013-12-01

    The chromaticity diagram is also needed in the instrument of a non-contact system for measuring color of printed material. The purpose of this paper is to design the color chromaticity diagram identical with the CIE 1931 and its program in MATLAB with digital image processing is realized. The chromaticity diagram in a binary format representation as black and white is used and the boundary for every color is confined by a closed black real line. More than 20 kinds of colors are selected by the psychophysiology of vision according to the CIE 1931 and their values in RGB are also are given. After every region colors are put in, the closed black real lines are wiped away and their values of RGB are updated according to the value for the nearest color region. The program including the filters in RGB space run until the all steps between every two colors up to the psychophysiology of vision, the chromaticity diagram is obtained. The values of RGB in every position in the chromaticity diagram can be presented.

  7. Improving the Science Process Skills Ability of Science Student Teachers Using I Diagrams

    Directory of Open Access Journals (Sweden)

    Sevilay Karamustafao?lu

    2011-04-01

    Full Text Available This study was carried out to identify the level of Science and Technology student teachers’ science processskills and to determine how efficient I diagrams are in developing these skills. The corpus of the study wasconsisted of 40 science and technology student teachers who were having Instructional Technologies andMaterial Design course during the 2009-10 academic years at Amasya University, Faculty of Education. Thestudy was conducted as a basic experimental design. A science process skills test was applied on the studentteachers as pre-test and post-test, then the points they got from each test were compared. During the study, thestudent teachers developed I-diagrams on science topics with the guidance of their supervisors. The resultsrevealed that the student teachers had problems with the pre-tests, and especially with the integrated processskill. At the end of the study it was observed that the student teachers’ skills on developing I-diagrams wereincreased as well as their integrated process skills problems were disappeared. Accordingly, it was concludedthat I-diagrams were important for the acquisition and development of science process skills.

  8. Phase diagrams of heterogeneous traffic flow at a single intersection in a deterministic Fukui-Ishibashi cellular automata traffic model

    Science.gov (United States)

    Li, Qi-Lang; Jiang, Rui; Min, Jie; Xie, Jia-Rong; Wang, Bing-Hong

    2014-10-01

    This paper studies heterogeneous traffic flow that comprises two types of vehicles with different lengths at a single intersection consisting of two perpendicular one-lane roads. Based on theoretical analysis and computer simulations, we have presented the phase diagrams which consist of five regions and the topological structure of which is independent of the maximum velocity of vehicles m. The analytical formulas of the flows on the two roads have been obtained in all regions of the phase diagram, which depends on whether m is even or odd or m = 1. The analytical formulas are in good agreement with simulation results.

  9. Flow Logic for Process Calculi

    DEFF Research Database (Denmark)

    Nielson, Hanne Riis; Nielson, Flemming

    2012-01-01

    Flow Logic is an approach to statically determining the behavior of programs and processes. It borrows methods and techniques from Abstract Interpretation, Data Flow Analysis and Constraint Based Analysis while presenting the analysis in a style more reminiscent of Type Systems. Traditionally developed for programming languages, this article provides a tutorial development of the approach of Flow Logic for process calculi based on a decade of research. We first develop a simple analysis for the ?-calculus; this consists of the specification, semantic soundness (in the form of subject reduction and adequacy results), and a Moore Family result showing that a least solution always exists, as well as providing insights on how to implement the analysis. We then show how to strengthen the analysis technology by introducing reachability components, interaction points, and localized environments, and finally, we extend it to a relational analysis. A Flow Logic is a program logic---in the same sense that a Hoare’s logic is. We conclude with an executive summary presenting the highlights of the approach from this perspective including a discussion of theoretical properties as well as implementation considerations. The electronic supplements present an application of the analysis techniques to a version of the ?-calculus incorporating distribution and code mobility; also the proofs of the main results can be found in the electronic supplements.

  10. Linking attentional processes and conceptual problem solving: visual cues facilitate the automaticity of extracting relevant information from diagrams

    OpenAIRE

    Rouinfar, Amy; Agra, Elise; Larson, Adam M.; Rebello, N. Sanjay; Loschky, Lester C.

    2014-01-01

    This study investigated links between visual attention processes and conceptual problem solving. This was done by overlaying visual cues on conceptual physics problem diagrams to direct participants’ attention to relevant areas to facilitate problem solving. Participants (N = 80) individually worked through four problem sets, each containing a diagram, while their eye movements were recorded. Each diagram contained regions that were relevant to solving the problem correctly and separate reg...

  11. Development of the web-based site investigation flow diagram in repository development program

    International Nuclear Information System (INIS)

    In siting a repository for high level radioactive wastes (HLW), it is essential for consensus building intelligibly and visually present why and how the area is selected as a suitable site. However 'information asymmetry' exists especially between society and an implementation body because various types of investigation, analysis and assessment are implemented in site characterization on the basis of a wide variety of advanced science and technology. Communication between experts (e.g. surveyors and modelers) is also important for efficient and reliable site investigation/ characterization. The Web-based Site Investigation Flow Diagram (SIFD) has been developed as a tool for information sharing among stake holders and society-jointed decision making. To test applicability of the SIFD, virtual site characterization ('dry run') is performed using the existing site investigation data. It is concluded that the web-based SIFD enhance traceability and transparency of the site investigation/ characterization, and therefore it would be a powerful communication tool among experts for efficient and reliable site investigation/characterization and among stake holders for consensus building

  12. A proposal for a method to translate MAP model into BPMN process diagram

    Directory of Open Access Journals (Sweden)

    Houda Kaffela

    2014-10-01

    Full Text Available This work presents a method to bridge the gap between intentional process modeling and business process modeling. The first represent the business objectives of an enterprise and the strategies used in order to achieve these objectives, while the second concentrate on the business processes. The proposed method uses MAP as an intentional modeling language and Business Process Modeling Notation (BPMN as a modeling language for the business processes. We propose to translate the strategic goals expressed with MAP model into a BPMN process diagram. We show that an alignment of the intentional model (MAP with BPMN can support the designers in transforming easily the strategic goals into business operational goals. We also show in this work, an example illustrating the use of our mapping.

  13. From State Diagram to Class Diagram

    DEFF Research Database (Denmark)

    Borch, Ole; Madsen, Per Printz

    2009-01-01

    UML class diagram and Java source code are interrelated and Java code is a kind of interchange format. Working with UML state diagram in CASE tools, a corresponding xml file is maintained. Designing state diagrams is mostly performed manually using design patterns and coding templates - a time consuming process. This article demonstrates how to compile such a diagram into Java code and later, by reverse engineering, produce a class diagram. The process from state diagram via intermediate SAX parsed xml file to Apache Velocity generated Java code is described. The result is a fast reproducible Java code minimizing maintenance.

  14. Student Understanding Of The Physics And Mathematics Of Process Variables In P-V Diagrams

    Science.gov (United States)

    Pollock, Evan B.; Thompson, John R.; Mountcastle, Donald B.

    2007-11-01

    Students in an upper-level thermal physics course were asked to compare quantities related to the First Law of Thermodynamics along with similar mathematical questions devoid of all physical context. We report on a comparison of student responses to physics questions involving interpretation of ideal gas processes on P-V diagrams and to analogous mathematical qualitative questions about the signs of and comparisons between the magnitudes of various integrals. Student performance on individual questions combined with performance on the paired questions shows evidence of isolated understanding of physics and mathematics. Some difficulties are addressed by instruction.

  15. Meaning and Abduction as Process-Structure: A Diagram of Reasoning

    Directory of Open Access Journals (Sweden)

    Inna Semetsky

    2009-11-01

    Full Text Available This paper is informed by Charles Sanders Peirce’s philosophy as semiotics or the doctrine of signs. The paper’s purpose is to explore Peirce’s category of abduction as not being limited to the inference to the best explanation. In the context of the logic of discovery, abduction is posited as a necessary although not sufficient condition for the production of meanings. The structure of a genuine sign is triadic and represents a synthesis between precognitive ideas and conceptual representations. The novel model of reasoning is offered, based on the mathematical formalism borrowed from Gauss’ interpretation of the complex number. It is suggested that this model in a form of a diagram not only represents a semiotic process-structure but also overcomes the long-standing paradox of new knowledge. For Peirce, it is a diagram as a visual representation that may yield solutions to the otherwise unsolvable logical problems. What appears to us as a paradox is the very presence of abductive, or hypothetical, inference, as Peircean generic category of Firstness within the Thirdness of the total thought-process. Firstness (feeling, Secondness (action, and Thirdness (reason together constitute a dynamic structure of experience.

  16. Systematic fuel cycle systems engineering from 2D flow diagrams to 3D layout

    International Nuclear Information System (INIS)

    The ITER fuel cycle systems are designed to supply deuterium-tritium gas mixtures to the ITER fueling systems and to process return gas streams from the vacuum vessel forming the closed inner fuel cycle. The radioactive nature of tritium requires implementation of a multiple barrier concept in order to assure the confinement of tritium within the process equipment. Ventilation and vent detritiation systems are the part of a dynamic confinement barrier which prevents tritium releases to the environment. The ITER fuel cycle systems, ventilation and tritium confinement systems all together form a rather complex chemical plant - the ITER Tritium Plant. Not only because of the complexity of the inner fuel cycle systems and numerous interfaces to the other systems within tritium plant but also because of the procurement sharing integrated planning is required. Interfaces management, configuration control and systems integration requires proper CAD tools and Project Data Management systems. CATIA V4 has been used in the past in ITER for 3D planning. However, only today's version of the software allows linking of the primarily 2D Pipe and Instrumentation Diagrams (P and IDs) into detailed 3D design and layout. The capabilities of the software were demonstrated through proof of principle activities in the ITER CAD office, eventually leading to the decision to deploy CATIA V5 Equipment and Systems (E and S) as general purpose single CAD tool for the design and integration of th tool for the design and integration of the ITER electrical, fluid and mechanical systems. In order to meet engineering requirements of ITER the CATIA V5 E and S project structure and project resources have been established starting from systems classifications, followed by the implementation of the applicable industrial standards, specifications and systems elements libraries into the Project Resources Management (PRM). Catalogues for the piping parts, piping specifications and standards specific for the design of the tritium processing systems and tritium confinement systems will assure implementation of the Design Guidelines and Quality Requirements for the Tritium Plant systems including the standardization of the equipment and design. The paper describes the CATIA V5 E and S project structure, the procedures to develop and maintain the PRM and how the tool is employed to detail the design of Tritium Plant systems. (orig.)

  17. Preliminary investigation of processing and phase diagram construction in the Y-Sr-Cu-O system

    International Nuclear Information System (INIS)

    This paper investigates the Y-Sr-Cu-O system which has been reported to from a K2NiF4-type superconducting phase (Tc ? 40 K) and a 123-type phase (Tc ? 80 K). Difficulties in preparing single phase materials by standard solid state reaction of carbonates and oxides have compelled us to explore other methods. A two-stage solid state processing technique in addition to a coprecipitation method will be discussed along with the relative advantages and disadvantages of each. Using data obtained from XRD and EDS, we have mapped some of the YO1.5SrO-CuO ternary phase diagram in anticipation of continued efforts at single crystal growth

  18. Image processing system for flow pattern measurements

    International Nuclear Information System (INIS)

    This paper describes the development and application of an image processing system for measurements of flow patterns occuring in natural circulation water flows. In this method, the motions of particles scattered in the flow are visualized by a laser light slit and they are recorded on normal video tapes. These image data are converted to digital data with an image processor and then transfered to a large computer. The center points and pathlines of the particle images are numerically analized, and velocity vectors are obtained with these results. In this image processing system, velocity vectors in a vertical plane are measured simultaneously, so that the two dimensional behaviors of various eddies, with low velocity and complicated flow patterns usually observed in natural circulation flows, can be determined almost quantitatively. The measured flow patterns, which were obtained from natural circulation flow experiments, agreed with photographs of the particle movements, and the validity of this measuring system was confirmed in this study. (author)

  19. Water conservation and reuse using the Water Sources Diagram method for batch process: case studies

    Directory of Open Access Journals (Sweden)

    Fernando Luiz Pellegrini Pessoa

    2012-04-01

    Full Text Available The water resources management has been an important factor for the sustainability of industrial processes, since there is a growing need for the development of methodologies aimed at the conservation and rational use of water. The objective of this work was to apply the heuristic-algorithmic method called Water Sources Diagram (WSD, which is used to define the target of minimum water consumption, to batch processes. Scenarios with reuse of streams were generated and evaluated with application of the method from the data of water quantity and concentration of contaminants in the operations. Two case studies aiming to show the reduction of water consumption and wastewater generation, and final treatment costs besides investment in storage tanks, were presented. The scenarios showed great promising, achieving reduction up to 45% in water consumption and wastewater generation, and a reduction of around 37% on cost of storage tanks, without the need to allocate regeneration processes. Thus, the WSD method showed to be a relevant and flexible alternative regarding to systemic tools aimed at minimizing the consumption of water in industrial processes, playing an important role within a program of water resources management.

  20. ISSUES CONCERNING THE USE OF UML DIAGRAMS TO DEFINE THE UNDERLYING PROCESS MODEL SIMULATION

    OpenAIRE

    MIOARA UDRIC?; TEODORA V?TUIU; ADRIAN GHENCEA

    2011-01-01

    Diagrams are a graphical representation of the information contained in a UML model, and are an essential feature of UML modelling. Each UML diagram is designed to let you view a software system from a different perspective and to varying levels of abstraction.

  1. Digital image processing for flow visualization

    International Nuclear Information System (INIS)

    The digital image processing for flow visualization pictures, including air-bubble, smoke tunnel, schlieren, and interference are described. The methods of calculating data are provided. The histogram equalization, spatial convolution, exponential transform, and Wallis transform are introduced

  2. T–S diagram efficiency analysis of two-step thermochemical cycles for solar water splitting under various process conditions

    International Nuclear Information System (INIS)

    Temperature–entropy diagrams combined with a pinch point analysis are introduced, providing a vivid and detailed tool to analyse two-step thermochemical water-splitting processes. The impacts of different temperature and pressure conditions, as well as different water conversion rates, are studied. Further, requirements regarding the entropy change in the redox material to reach desired process conditions are presented. This paper provides insights on how future research shall be oriented to achieve optimal conditions for this challenging but also very promising class of reactions. - Highlights: • Representation of two-step thermochemical cycles for water splitting in comprehensive T–S diagrams. • Influence of process conditions (pressure, temperature, conversion) on the thermodynamic efficiency is shown. • Identification of entropy requirements of redox materials when aiming at certain process conditions. • Results show efficiency trends which provide valuable insight for conceptual process layout

  3. Flow, diffusion, and rate processes

    International Nuclear Information System (INIS)

    This volume contains recent results obtained for the nonequilibrium thermodynamics of transport and rate processes are reviewed. Kinetic equations, conservation laws, and transport coefficients are obtained for multicomponent mixtures. Thermodynamic principles are used in the design of experiments predicting heat and mass transport coefficients. Highly nonstationary conditions are analyzed in the context of transient heat transfer, nonlocal diffusion in stress fields and thermohydrodynamic oscillatory instabilities. Unification of the dynamics of chemical systems with other sorts of processes (e.g. mechanical) is given. Thermodynamics of reacting surfaces is developed. Admissible reaction paths are studied and a consistency of chemical kinetics with thermodynamics is shown. Oscillatory reactions are analyzed in a unifying approach showing explosive, conservation or damped behavior. A comprehensive review of transport processes in electrolytes and membranes is given. Applications of thermodynamics to thermoelectric systems and ionized gas (plasma) systems are reviewed

  4. Petri net to ladder logic diagram converter and a batch process simulation

    Directory of Open Access Journals (Sweden)

    Mostafa M. Gomaa

    2011-02-01

    Full Text Available Discrete-event dynamic systems (DEDS are characterized by a set of states which the system can take, and by the set of asynchronous events that cause the state changes at discrete time points. Programmable logic controllers (PLCs are still important special purpose computers used to automate the DEDS in industry. Ladder logic diagrams (LLDs are still the most popular graphical programming tools of the PLCs; but the major problem is that programming is done heuristically and the LLDs are difficult to be used for both analysis and performance evaluation. Petri nets (PNs are nowadays the most effective modeling environment for both the design and implementation of DEDS. This paper proposes a PN to LLD conversion tool, used for graphical editing of a PN net model of a DEDS controller and for converting this PN into the equivalent LLD for programming a PLC. The conversion algorithm is presented, considering many types of transitions, places, and arcs with generality that many types of PNs can be considered. This paper also presents a simulation of a batch process, on a personal computer from one side, interfaced with a real PLC from the other side, that is programmed using a LLD obtained from the conversion of a suitable PN model using the proposed conversion tool. Compared with a LDD got heuristically, the LLD got from a PN conversion is simpler, understandable, and meeting all the characteristics obtained from the PN analysis.

  5. 18 CFR 260.8 - System flow diagrams: Format No. FERC 567.

    Science.gov (United States)

    2010-04-01

    ...APPROVED FORMS, NATURAL GAS ACT STATEMENTS AND...Each Major natural gas pipeline company...fields, crossovers, compressor stations and connections with...flow can be reversed at compressor stations, so indicate....

  6. A Comprehensive Wiring Diagram of the Protocerebral Bridge for Visual Information Processing in the Drosophila Brain

    Directory of Open Access Journals (Sweden)

    Chih-Yung Lin

    2013-05-01

    Full Text Available How the brain perceives sensory information and generates meaningful behavior depends critically on its underlying circuitry. The protocerebral bridge (PB is a major part of the insect central complex (CX, a premotor center that may be analogous to the human basal ganglia. Here, by deconstructing hundreds of PB single neurons and reconstructing them into a common three-dimensional framework, we have constructed a comprehensive map of PB circuits with labeled polarity and predicted directions of information flow. Our analysis reveals a highly ordered information processing system that involves directed information flow among CX subunits through 194 distinct PB neuron types. Circuitry properties such as mirroring, convergence, divergence, tiling, reverberation, and parallel signal propagation were observed; their functional and evolutional significance is discussed. This layout of PB neuronal circuitry may provide guidelines for further investigations on transformation of sensory (e.g., visual input into locomotor commands in fly brains.

  7. Phase diagram and breathing dynamics of a single red blood cell and a biconcave capsule in dilute shear flow

    Science.gov (United States)

    Yazdani, Alireza Z. K.; Bagchi, Prosenjit

    2011-08-01

    We present phase diagrams of the single red blood cell and biconcave capsule dynamics in dilute suspension using three-dimensional numerical simulations. The computational geometry replicates an in vitro linear shear flow apparatus. Our model includes all essential properties of the cell membrane, namely, the resistance against shear deformation, area dilatation, and bending, as well as the viscosity difference between the cell interior and suspending fluids. By considering a wide range of shear rate and interior-to-exterior fluid viscosity ratio, it is shown that the cell dynamics is often more complex than the well-known tank-treading, tumbling, and swinging motion and is characterized by an extreme variation of the cell shape. As a result, it is often difficult to clearly establish whether the cell is swinging or tumbling. Identifying such complex shape dynamics, termed here as “breathing” dynamics, is the focus of this article. During the breathing motion at moderate bending rigidity, the cell either completely aligns with the flow direction and the membrane folds inward, forming two cusps, or it undergoes large swinging motion while deep, craterlike dimples periodically emerge and disappear. At lower bending rigidity, the breathing motion occurs over a wider range of shear rates, and is often characterized by the emergence of a quad-concave shape. The effect of the breathing dynamics on the tank-treading-to-tumbling transition is illustrated by detailed phase diagrams which appear to be more complex and richer than those of vesicles. In a remarkable departure from the vesicle dynamics, and from the classical theory of nondeformable cells, we find that there exists a critical viscosity ratio below which the transition is independent of the viscosity ratio, and dependent on shear rate only. Further, unlike the reduced-order models, the present simulations do not predict any intermittent dynamics of the red blood cells.

  8. ASPECTS OF ROBUSTNESS IN FLOW CONTROL PROCESSES

    OpenAIRE

    Dulau, Mircea; Grif, Horatiu; Oltean, Stelian

    2011-01-01

    In the industrial domain, a large number of applications is covered by slow processes, including the flow, the pressure, the temperature and the level control. Each control system must be treated in steady and dynamic states and from the point of view of the possible technical solutions. Based on mathematical models of the processes and design calculations, PC programs allow simulation and the determination of the control system performances. The paper presents a part of an industrial process...

  9. Stereo Diagrams

    Science.gov (United States)

    Dexter Perkins

    This exercise is an introduction to stereo diagrams. Students draw stereo diagrams for various models, determine the point group and crystal system of certain crystal shapes, and determine which block models match given stereo diagrams.

  10. Prolog Visualization System Using Logichart Diagrams

    CERN Document Server

    Adachi, Yoshihiro

    2009-01-01

    We have developed a Prolog visualization system that is intended to support Prolog programming education. The system uses Logichart diagrams to visualize Prolog programs. The Logichart diagram is designed to visualize the Prolog execution flow intelligibly and to enable users to easily correlate the Prolog clauses with its parts. The system has the following functions. (1) It visually traces Prolog execution (goal calling, success, and failure) on the Logichart diagram. (2) Dynamic change in a Prolog program by calling extra-logical predicates, such as `assertz' and `retract', is visualized in real time. (3) Variable substitution processes are displayed in a text widget in real time.

  11. ESPC Overview: Cash Flows, Scenarios, and Associated Diagrams for Energy Savings Performance Contracts

    Energy Technology Data Exchange (ETDEWEB)

    Tetreault, T.; Regenthal, S.

    2011-05-01

    This document is meant to inform state and local decision makers about the process of energy savings performance contracts, and how projected savings and allocated energy-related budgets can be impacted by changes in utility prices.

  12. On a generalized phase diagram of simultaneous transport processes - a two velocity universal plane of invariance

    International Nuclear Information System (INIS)

    The problem concerning void fraction as an additional degree of freedom for a discontinuous density continuum e.g., two-phase systems, is theoretically investigated. A generalized phase diagram has been found to signify the evolution of two-phase systems. With due regard to the objective property of motion, the transformation functions and its properties clearly expose the invariance of relative velocity with superficial velocities as the vector quantities. A fundamental one-to-one mapping involving Euclidean point spaces has been derived demonstrating a two-velocity universal plane of invariance as two-phase equation-of-state. The utility of the phase diagram for steady-state operations is doubtless because of the fundamental property of motion. (author)

  13. ROLE OF UML SEQUENCE DIAGRAM CONSTRUCTS IN OBJECT LIFECYCLE CONCEPT

    OpenAIRE

    Miroslav Grgec; Robert Mužar

    2007-01-01

    When modeling systems and using UML concepts, a real system can be viewed in several ways. The RUP (Rational Unified Process) defines the "4 + 1 view": 1. Logical view (class diagram (CD), object diagram (OD), sequence diagram (SD), collaboration diagram (COD), state chart diagram (SCD), activity diagram (AD)), 2.Process view (use case diagram, CD, OD, SD, COD, SCD, AD), 3. Development view (package diagram, component diagram), 4. Physical view (deployment diagram), and 5. Use case view (use ...

  14. Fluid Flow Properties of WAG Injection Processes

    OpenAIRE

    Dale, Elisabeth Iren; Skauge, Arne

    2008-01-01

    Immiscible water-alternating-gas (IWAG) experiments performed on equilibrated fluids are summarised together with the corresponding two-phase gas-oil and water-oil displacements. Experimental studies at reservoir condition and also mechanistic experiments over many years have shown accelerated oil production and higher core flood oil recovery as a result of three-phase flow. The three-phase effects that are included and analysed are; trapped gas, and mobility for secondary process...

  15. Efficient transformation of use case main success scenario steps into bussiness object relation (BORM) diagrams for effective bussiness process requirement analysis.

    Czech Academy of Sciences Publication Activity Database

    Podaras, A.; Moravec, J.; Papík, Martin

    2012-01-01

    Ro?. 2, ?. 1 (2012), s. 86-88. ISSN 1804-7890 Institutional research plan: CEZ:AV0Z10750506 Keywords : Business process requirement Analysis * UCBTA Algorithm * UCBTA Transition Rules * Use Case Main Success Scenario Steps * BORM Diagrams Subject RIV: IN - Informatics, Computer Science http://library.utia.cas.cz/separaty/2012/ZOI/papik-efficient transformation of use case main success scenario steps into bussiness object relation (borm) diagrams for effective bussiness process requirement analysis.pdf

  16. Multiphase Flow Modeling of Biofuel Production Processes

    Energy Technology Data Exchange (ETDEWEB)

    D. Gaston; D. P. Guillen; J. Tester

    2011-06-01

    As part of the Idaho National Laboratory's (INL's) Secure Energy Initiative, the INL is performing research in areas that are vital to ensuring clean, secure energy supplies for the future. The INL Hybrid Energy Systems Testing (HYTEST) Laboratory is being established to develop and test hybrid energy systems with the principal objective to safeguard U.S. Energy Security by reducing dependence on foreign petroleum. HYTEST involves producing liquid fuels in a Hybrid Energy System (HES) by integrating carbon-based (i.e., bio-mass, oil-shale, etc.) with non-carbon based energy sources (i.e., wind energy, hydro, geothermal, nuclear, etc.). Advances in process development, control and modeling are the unifying vision for HES. This paper describes new modeling tools and methodologies to simulate advanced energy processes. Needs are emerging that require advanced computational modeling of multiphase reacting systems in the energy arena, driven by the 2007 Energy Independence and Security Act, which requires production of 36 billion gal/yr of biofuels by 2022, with 21 billion gal of this as advanced biofuels. Advanced biofuels derived from microalgal biomass have the potential to help achieve the 21 billion gal mandate, as well as reduce greenhouse gas emissions. Production of biofuels from microalgae is receiving considerable interest due to their potentially high oil yields (around 600 gal/acre). Microalgae have a high lipid content (up to 50%) and grow 10 to 100 times faster than terrestrial plants. The use of environmentally friendly alternatives to solvents and reagents commonly employed in reaction and phase separation processes is being explored. This is accomplished through the use of hydrothermal technologies, which are chemical and physical transformations in high-temperature (200-600 C), high-pressure (5-40 MPa) liquid or supercritical water. Figure 1 shows a simplified diagram of the production of biofuels from algae. Hydrothermal processing has significant advantages over other biomass processing methods with respect to separations. These 'green' alternatives employ a hybrid medium that, when operated supercritically, offers the prospect of tunable physicochemical properties. Solubility can be rapidly altered and phases partitioned selectively to precipitate or dissolve certain components by altering temperature or pressure in the near-critical region. The ability to tune the solvation properties of water in the highly compressible near-critical region facilitates partitioning of products or by-products into separate phases to separate and purify products. Since most challenges related to lipid extraction are associated with the industrial scale-up of integrated extraction systems, the new modeling capability offers the prospect of addressing previously untenable scaling issues.

  17. The influence of random slowdown process and lock-step effect on the fundamental diagram of the nonlinear pedestrian dynamics: An estimating-correction cellular automaton

    Science.gov (United States)

    Fu, Zhijian; Zhou, Xiaodong; Chen, Yanqiu; Gong, Junhui; Peng, Fei; Yan, Zidan; Zhang, Taolin; Yang, Lizhong

    2015-03-01

    Random slowdown process and lock-step effect, observed from real-life observation and the experiments of other researchers, were investigated in the view of the pedestrian microscopic behaviors. Due to the limited controllability, repeatability and randomness of the pedestrian experiments, a new estimating-correction cellular automaton was established to research the influence of random slowdown process and lock-step effect on the fundamental diagram. The first step of the model is to estimate the next time-step status of the neighbor cell in front of the tracked pedestrian. The second step is to correct the status and confirm the position of the tracked pedestrian in the next time-step. It is found that the random slowdown process and lock-step have significant influence on the curve configuration and the characteristic parameters, including the concavity-convexity, the inflection point, the maximum flow rate and the critical density etc. The random slowdown process reduces the utilization of the available space between two adjacent pedestrians in the longitudinal direction, especially in the region of intermediate density. However, the lock-step effect enhances the utilization of the available space, especially in the region of high density.

  18. The perceptual flow of phonetic feature processing

    DEFF Research Database (Denmark)

    Greenberg, Steven; Christiansen, Thomas Ulrich

    2008-01-01

    How does the brain process spoken language? It is our thesis that word intelligibility and consonant identification are insufficient by themselves to model how the speech signal is decoded - a finer-grained approach is required. In this study, listeners identified 11 different Danish consonants spoken in a Consonant + Vowel + [l] environment. Each syllable was processed so that only a portion of the original audio spectrum was present. Three-quarter-octave bands of speech, centered at 750, 1500, and 3000 Hz, were presented individually and in combination with each other. The conditional, posterior probabilities associated with phonetic-feature decoding were computed from confusion matrices in order to deduce the temporal flow of phonetic processing. Decoding the feature, Manner-of-Articulation, depends on accurate decoding of the feature Voicing (but not vice-versa), and decoding Place-of-Articulation requires precise decoding of Manner (but not the converse). From these data, we conclude that Voicing is processed prior to Manner-of-Articulation, and that Manner is decoded prior to Place-of-Articulation. Voicing and Manner cues are often correctly decoded in conditions where Place is not. This asymmetric pattern of feature decoding may provide extra-segmental information of utility for speech processing, particularly in adverse listening conditions.

  19. Flow processes in a radiant tube burner: Combusting flow

    International Nuclear Information System (INIS)

    Highlights: ? 3D combusting flow in an industrial radiant tube burner is modelled using the ANSYS-CFX CFD code. ? Results are validated against data from an industrial furnace (NO emissions within 7%). ? The flame is long and narrow with slight asymmetry. Mixing near the fuel injector is very effective. ? The recuperator section is reasonably effective, but design improvements are proposed. ? The design is vulnerable to eccentricities due to manufacturing or assembly tolerances. -- Abstract: This paper describes a study of the combustion process in an industrial radiant tube burner (RTB), used in heat treating furnaces, as part of an attempt to improve burner performance. A detailed three-dimensional Computational Fluid Dynamics model has been used, validated with experimental test furnace temperature and flue gas composition measurements. Simulations using the Eddy Dissipation combustion model with peak temperature limitation and the Discrete Transfer radiation model showed good agreement with temperature measurements in the inner and outer walls of the burner, as well as with flue gas composition measured at the exhaust (including NO). Other combustion and radiation models were also tested but gave inferior results in various aspects. The effects of certain RTB design features are analysed, and an analysis of the heat transfer processes within the burner is presented.

  20. Grid diagrams and shellability

    OpenAIRE

    Sarkar, Sucharit

    2009-01-01

    We explore a somewhat unexpected connection between knot Floer homology and shellable posets, via grid diagrams. Given a grid presentation of a knot K inside S^3, we define a poset which has an associated chain complex whose homology is the knot Floer homology of K. We then prove that the closed intervals of this poset are shellable. This allows us to combinatorially associate a PL flow category to a grid diagram.

  1. Carroll Diagrams

    Science.gov (United States)

    NRICH team

    2012-01-01

    In this number sorting activity students must use a Carroll Diagram to determine which two categories each number fits into. This activity can be completed in pairs or groups on printable versions or it can be completed as a whole class using the interactive white board (IWB). Included with this resource are printable versions of the Carroll Diagrams, guiding questions, extension and support suggestions, and a link to more challenging "More Carroll Diagrams".

  2. Phase diagrams

    International Nuclear Information System (INIS)

    The plotting of phase diagrams of two- and three-component system both in composition - temperature coordinates and in other coordinates, which are thermodynamic parameters of the phases (total pressure in the system, mole volume, chemical potentials of components, etc.) are considered. Phase diagrams are classified, while calculation and experimental methods of their plotting are described

  3. Phase Diagrams

    Science.gov (United States)

    This problem set challenges students to interpret a simplified temperature-composition phase diagram for the system enstatite (Mg2Si2O6) - diopside (CaMgSi2O6), which are common constituents of peridotites, gabbros, and basalts. Students are provided with the phase diagram and asked to answer 13 questions about it.

  4. A Feynman Diagram Analyser DIANA

    OpenAIRE

    Tentyukov, M.; Fleischer, J.

    1999-01-01

    A C-program DIANA (DIagram ANAlyser) for the automatic Feynman diagram evaluation is presented. It consists of two parts: the analyzer of diagrams and the interpreter of a special text manipulating language. This language is used to create a source code for analytical or numerical evaluations and to keep the control of the process in general.

  5. Human Factors Operability Timeline Analysis to Improve the Processing Flow of the Orion Spacecraft

    Science.gov (United States)

    Stambolian, Damon B.; Schlierf, Roland; Miller, Darcy; Posada, Juan; Haddock, Mike; Haddad, Mike; Tran, Donald; Henderon, Gena; Barth, Tim

    2011-01-01

    This slide presentation reviews the use of Human factors and timeline analysis to have a more efficient and effective processing flow. The solution involved developing a written timeline of events that included each activity within each functional flow block. Each activity had computer animation videos and pictures of the people involved and the hardware. The Human Factors Engineering Analysis Tool (HFEAT) was improved by modifying it to include the timeline of events. The HFEAT was used to define the human factors requirements and design solutions were developed for these requirements. An example of a functional flow block diagram is shown, and a view from one of the animations (i.e., short stack pallet) is shown and explained.

  6. Control Flow Pattern Recognition for BPMN Process Models

    OpenAIRE

    Yeh-Chun Juan; Kuo-Yen Yuan

    2013-01-01

    Business process modeling is the first and the most important task in business process management (BPM). Business process models are implicitly composed of a set of control flow patterns, such as the Parallel Split, Synchronization, Exclusive Choice, and Simple Merge, etc. Several studies have proposed the concepts and definitions of control flow patterns. But, few analyzed the structure of process models to identify the constituent control flow patterns. This research proposes a three-phased...

  7. Some limit theorems for flows of branching processes

    CERN Document Server

    He, Hui

    2012-01-01

    We construct two kinds of stochastic flows of discrete Galton-Watson branching processes. Some scaling limit theorems for the flows are proved, which lead to local and nonlocal branching superprocesses over the positive half line.

  8. Equivalent Temperature-Enthalpy Diagram for the Study of Ejector Refrigeration Systems

    OpenAIRE

    Mohammed Khennich; Mikhail Sorin; Nicolas Galanis

    2014-01-01

    The Carnot factor versus enthalpy variation (heat) diagram has been used extensively for the second law analysis of heat transfer processes. With enthalpy variation (heat) as the abscissa and the Carnot factor as the ordinate the area between the curves representing the heat exchanging media on this diagram illustrates the exergy losses due to the transfer. It is also possible to draw the paths of working fluids in steady-state, steady-flow thermodynamic cycles on this diagram using the def...

  9. Hanford Site Treated Effluent Disposal Facility process flow sheet

    International Nuclear Information System (INIS)

    This report presents a novel method of using precipitation, destruction and recycle factors to prepare a process flow sheet. The 300 Area Treated Effluent Disposal Facility (TEDF) will treat process sewer waste water from the 300 Area of the Hanford Site, located near Richland, Washington, and discharge a permittable effluent flow into the Columbia River. When completed and operating, the TEDF effluent water flow will meet or exceed water quality standards for the 300 Area process sewer effluents. A preliminary safety analysis document (PSAD), a preconstruction requirement, needed a process flow sheet detailing the concentrations of radionuclides, inorganics and organics throughout the process, including the effluents, and providing estimates of stream flow quantities, activities, composition, and properties (i.e. temperature, pressure, specific gravity, pH and heat transfer rates). As the facility begins to operate, data from process samples can be used to provide better estimates of the factors, the factors can be entered into the flow sheet and the flow sheet will estimate more accurate steady state concentrations for the components. This report shows how the factors were developed and how they were used in developing a flow sheet to estimate component concentrations for the process flows. The report concludes with how TEDF sample data can improve the ability of the flow sheet to accurately predict concentrations of components in the process

  10. Multi-Particle Processes in the Standard Model without Feynman Diagrams

    CERN Document Server

    Papadopoulos, C G; Papadopoulos, Costas G.; Worek, Malgorzata

    2005-01-01

    A method to efficiently compute, in a automatic way, helicity amplitudes for arbitrary scattering processes at leading order in the Standard Model is presented. The scattering amplitude is evaluated recursively through a set of Dyson-Schwinger equations. The computational cost of this algorithm grows asymptotically as 3^n, where n is the number of particles involved in the process, compared to n! in the traditional Feynman graphs approach. Unitary gauge is used and mass effects are available as well. Additionally, the color and helicity structures are appropriately transformed so the usual summation is replaced by Monte Carlo techniques. Some results related to the production of vector bosons and the Higgs boson in association with jets are also presented.

  11. Phase Diagrams in Vivo

    Science.gov (United States)

    This activity uses three experiments for students to construct a phase diagram; the experiments have been videotaped and can be seen online. The purpose of this laboratory as designed is to gain familiarity with simple phase diagrams, their construction, and their applications to the understanding of geological and environmental problems. Subsidiary objectives include development of strategies for data processing including evaluation of assumptions and sources of errors, as well as honing of computer, spreadsheet, presentation (tabular and graphical), and report writing skills.

  12. An active feedback flow control theory of the vortex breakdown process

    Science.gov (United States)

    Granata, Joshua

    An active feedback flow control theory of the vortex breakdown process in incompressible, axisymmetric swirling flows in a finite-length, straight, circular pipe is developed. Flow injection distributed along the pipe wall is used as the controller. The flow is subjected to non-periodic inlet and outlet conditions. A long-wave asymptotic analysis, which involves a re-scaling of the axial distance and time at near critical swirl ratios, results in a nonlinear model problem for the dynamics and control of both inviscid and high-Reynolds number, Re, flows. The approach provides the bifurcation diagram of steady states and the stability characteristics of these states. Computed examples of the flow dynamics based on the full Euler and Navier-Stokes formulations at various swirl levels demonstrate the evolution to near-steady breakdown states when swirl is above a critical level which depends on Re. Numerical stability and mesh convergence studies performed on the inviscid and high-Re flow simulations ensure the accuracy of the computations and the agreement with the theoretical approaches. In addition, an energy analysis of the nonlinear model problem sheds insight into the mechanisms of the flow dynamics which lead to vortex breakdown and suggests a feedback control law which relates the flow injection and the evolving maximum radial velocity at the inlet. Moreover, applying the proposed feedback control law during flow evolution, shows for the first time the successful and robust elimination of the breakdown states and flow stabilization on an almost columnar state for a wide range of swirl up to 53 percent above the first critical level for the inviscid flow case and for a range of swirl up to 15 percent above the first critical level for viscous flows. The control law can be improved for a lower momentary maximum flux injection through the use of discrete injection regions along the pipe. The feedback control cuts the natural feed-forward mechanism of the breakdown process. Specifically, in the case of high-Re flows, the control approach establishes a branch of columnar states for all swirl levels studied where in the natural flow dynamics no such states exist.

  13. Control Flow Pattern Recognition for BPMN Process Models

    Directory of Open Access Journals (Sweden)

    Yeh-Chun Juan

    2013-06-01

    Full Text Available Business process modeling is the first and the most important task in business process management (BPM. Business process models are implicitly composed of a set of control flow patterns, such as the Parallel Split, Synchronization, Exclusive Choice, and Simple Merge, etc. Several studies have proposed the concepts and definitions of control flow patterns. But, few analyzed the structure of process models to identify the constituent control flow patterns. This research proposes a three-phased framework to recognize the constituent control flow patterns and their interrelationship for a Business Process Modeling Notation (BPMN process model. The conceptual phase first describes the conceptual process for identifying the control flow patterns from a process model. The design phase then develops the detailed procedure and methods based on the proposed conceptual process to recognize the control flow patterns for a BPMN process model. Finally, the implementation phase carries out the proposed procedure and methods by developing a workflow pattern representation system for BPMN process models.

  14. Stochastic diagrams and Feynman diagrams

    International Nuclear Information System (INIS)

    We study the relationship between ordinary perturbation theory and perturbation theory obtained from stochastic quantization. We give a simple proof that, except in gauge theories, the several stochastic diagrams of a given topology are together equivalent to the corresponding Feynman diagram. Our analysis is presented in Minkowski space, but most of it may readily be adapted to euclidean space. The field propagator may be a non-diagonal matrix, such as is the case in real-time thermal field theory. We present a new version of the Langevin equation which directly reproduces the usual axial-gauge perturbation theory. Otherwise, we find that for gauge theories the relationship between ordinary and stochastic perturbation theory is not simple, and we present a recursive method of reconstructing Feynman diagrams from stochastic diagrams, without the need explicitly to introduce ghost fields. We consider both the original Parisi-Wu version of the Langevin equation, and Zwanziger's modified version with its stochastic gauge-fixing term. (orig.)

  15. Automatized material and radioactivity flow control tool in decommissioning process

    International Nuclear Information System (INIS)

    In this presentation the automatized material and radioactivity flow control tool in decommissioning process is discussed. It is concluded that: computer simulation of the decommissioning process is one of the important attributes of computer code Omega; one of the basic tools of computer optimisation of decommissioning waste processing are the tools of integral material and radioactivity flow; all the calculated parameters of materials are stored in each point of calculation process and they can be viewed; computer code Omega represents opened modular system, which can be improved; improvement of the module of optimisation of decommissioning waste processing will be performed in the frame of improvement of material procedures and scenarios.

  16. Kinetic diagrams of Ln2O2SO4 phase transformations in a H2 flow (Ln = La, Pr, Nd, Sm)

    Science.gov (United States)

    Sal'nikova, E. I.; Andreev, P. O.; Antonov, S. M.

    2013-08-01

    Kinetic diagrams of Ln2O2SO4 (Ln = La, Pr, Nd, Sm) systems reduction in a H2 flow are plotted for the first time in temperature-duration of treatment coordinates in which there are five areas of phase states. The temperatures of formation are established for products of the Ln2O2SO4 + 4H2 = Ln2O2S + 4H2O reaction in the temperature range of 880-900 K and products of the Ln2O2SO4 + H2 = Ln2O3 + SO2+ H2O reaction in the temperature range of 1090-1220 K. The ranges of the temperature of formation of the homo-geneous Ln2O2S phase were found to decrease: 880-1220, 900-1200, 900-1180, and 900-1090 K in the sequence La-Pr-Nd-Sm.

  17. Study of the condensation and flow of a simulated uranium-iron alloy in the liquid-solid domain of the phase diagram

    International Nuclear Information System (INIS)

    Silver-copper alloys with a composition entering a liquid-solid domain of the phase diagram are condensed on a titled molybdenum substrate, regulated in temperature. Droplets containing nodular crystals, for the most part in contact with the substrate, condense and coalesce to form a film. The film forms more quickly in the solid-liquid than in the fully liquid areas. It indicates that the crystals constitute pinning points for the droplets. A correlation between the condensate thickness and the local solid fraction at the transition between film and droplets is given. In the film areas, the gravity-dependent effect plays an important role. In case of the silver-rich condensate, the solid-phase is expected to be more easily driven by the liquid flow. (authors)

  18. Program Synthesizes UML Sequence Diagrams

    Science.gov (United States)

    Barry, Matthew R.; Osborne, Richard N.

    2006-01-01

    A computer program called "Rational Sequence" generates Universal Modeling Language (UML) sequence diagrams of a target Java program running on a Java virtual machine (JVM). Rational Sequence thereby performs a reverse engineering function that aids in the design documentation of the target Java program. Whereas previously, the construction of sequence diagrams was a tedious manual process, Rational Sequence generates UML sequence diagrams automatically from the running Java code.

  19. Stability Lobe Diagram for High Speed Machining Processes:Comparison of Experimental and Analytical Methods – A Review

    Directory of Open Access Journals (Sweden)

    PALPANDIAN P

    2013-03-01

    Full Text Available Chatter is a complicated problem faced by machine tool operators. Chatter is a self-excited vibration that can occur during machining operations. This is an undesirable phenomenon which limits the productivity of the machine. A lot of techniques have been developed to control the chatter. Stability lobe diagram is an effective tool which helps the operator to select specific spindle speeds during production to avoid chatter in machine. Stability lobes are plotted against axial depth of cut Vs spindle speed, which shows a boundary between stable and unstable cutting regions. Numerous experimental and analytical techniques have been developed to establish stability lobe diagram. This paper presents a review on experimental and analytical methods of obtaining stability lobe diagram in high speed milling operation.

  20. ????? ????? ??? ???????? ?? ????? ?????????????? ?????? ?????? ????? ( Window Diagram) ???????? ????? ????? ??????? ?????? ???????

    OpenAIRE

    Al Kathiri, M. N.

    1996-01-01

    Window diagram theory has been described by Purnell and his research team in various publications. In this paper we apply this theory to optimize a separation of complex mixture containing propylene oxide, 1-hexene, cyclohexene, tert. amylmethyl wther, 4-octene, 1-octyne, 1-nonene, p-xylene and n-decane by using two different polarity serial columns; squalane (SQ) as a non-polar solvent and Diisobutyl phthalate (DBP) as a polar solvent. A baseline separation of all mixture components is achie...

  1. Solar thermal aerosol flow reaction process

    Science.gov (United States)

    Weimer, Alan W.; Dahl, Jaimee K.; Pitts, J. Roland; Lewandowski, Allan A.; Bingham, Carl; Tamburini, Joseph R.

    2005-03-29

    The present invention provides an environmentally beneficial process using concentrated sunlight to heat radiation absorbing particles to carry out highly endothermic gas phase chemical reactions ultimately resulting in the production of hydrogen or hydrogen synthesis gases.

  2. The perceptual flow of phonetic feature processing

    OpenAIRE

    Greenberg, Steven; Christiansen, Thomas Ulrich

    2010-01-01

    How does the brain process spoken language? It is our thesis that word intelligibility and consonant identification are insufficient by themselves to model how the speech signal is decoded - a finer-grained approach is required. In this study, listeners identified 11 different Danish consonants spoken in a Consonant + Vowel + [l] environment. Each syllable was processed so that only a portion of the original audio spectrum was present. Three-quarter-octave bands of speech, centered at 750, 1...

  3. Information systems for material flow management in construction processes

    Science.gov (United States)

    Mesároš, P.; Mandi?ák, T.

    2015-01-01

    The article describes the options for the management of material flows in the construction process. Management and resource planning is one of the key factors influencing the effectiveness of construction project. It is very difficult to set these flows correctly. The current period offers several options and tools to do this. Information systems and their modules can be used just for the management of materials in the construction process.

  4. Study on two-phase flow using image processing technique

    International Nuclear Information System (INIS)

    Studies on water-air two-phase flow using KUR, NSRR, JRR3 was reported. In the KUR experiment, the average void fraction of two-phase flow in a narrow rectangular channel was measured by using image processing technique. In the NSRR experiment, the boiling two-phase flow in a small diameter tube was visualized by using pulsed neutron and high speed video system. In the JRR3 experiment, the two-phase flow in a small diameter tube was visualized and the results were compared with those in the KUR experiment. (author)

  5. Optimizatsion of tellurium distillation process in a hydrogen flow

    International Nuclear Information System (INIS)

    Optimization problems are considered of steady-state regime of the process of tellurium distillation in a hydrogen flow using the methods of the experiment planning theory and non-linear programming. An optimum regime of conducting the process is obtained that ensures 8% increase of the acceptable production yield

  6. Fast liquid-phase processes in turbulent flows

    CERN Document Server

    Minsker, Karl; Zakharov, Vadim; Zaikov, Gennady

    2004-01-01

    This book deals with the fundamental laws of passing of fast liquid-phase chemical as well as heat and mass transfer processes in turbulent flows. The fundamental laws of passing of fast liquid-phase chemical and also heat and mass transfer processes in turbulent flows are considered in the book. Development of a macrokinetics approach is generalized to the analysis of fast chemical reactions mainly based on an example of cationic isobutylene polymerization, which falls into to a new class of liquid-phase processes. The ways of decision of the hydrodynamical, thermal and kinetic movement’s e

  7. EtherNet/IP coriolis flow measurement for process applications

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-11-15

    The first process automation vendor to launch Ethernet/IP as a digital output was Endress + Hauser. The product was introduced for their Promass Coriolis mass flow meter product line. This paper presents the Ethernet/IP Coriolis flow measurement for process applications. The Ethernet/IP minimizes device complexity and enables a plant to integrate their Coriolis flow meters into existing Rockwell automation logix environments flawlessly. Ethernet/IP allows multiple process variables and device conditions to be converted to user control points. It has speeds of up to 100 mbps and is the world's fastest digital protocol. It is an open standard form of unmodified Ethernet that is well known to users. Results showed that Promass 83 demonstrated superior accuracy in competitive field trials. The customer results included 40% reduction in device commissioning and a 25% reduction in loop identification, device integration and process loop tuning.

  8. A Conductivity Relationship for Steady-state Unsaturated Flow Processes under Optimal Flow Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Liu, H. H.

    2010-09-15

    Optimality principles have been used for investigating physical processes in different areas. This work attempts to apply an optimal principle (that water flow resistance is minimized on global scale) to steady-state unsaturated flow processes. Based on the calculus of variations, we show that under optimal conditions, hydraulic conductivity for steady-state unsaturated flow is proportional to a power function of the magnitude of water flux. This relationship is consistent with an intuitive expectation that for an optimal water flow system, locations where relatively large water fluxes occur should correspond to relatively small resistance (or large conductance). Similar results were also obtained for hydraulic structures in river basins and tree leaves, as reported in other studies. Consistence of this theoretical result with observed fingering-flow behavior in unsaturated soils and an existing model is also demonstrated.

  9. On-line sample processing methods in flow analysis

    OpenAIRE

    Miro?, Manuel; Hansen, Elo Harald

    2008-01-01

    In this chapter, the state of the art of flow injection and related approaches thereof for automation and miniaturization of sample processing regardless of the aggregate state of the sample medium is overviewed. The potential of the various generation of flow injection for implementation of in-line dilution, derivatization, separation and preconcentration methods encompassing solid reactors, solvent extraction, sorbent extraction, precipitation/coprecipitation, hydride/vapor generation and d...

  10. Rotating Thermal Flows in Natural and Industrial Processes

    CERN Document Server

    Lappa, Marcello

    2012-01-01

    Rotating Thermal Flows in Natural and Industrial Processes provides the reader with a systematic description of the different types of thermal convection and flow instabilities in rotating systems, as present in materials, crystal growth, thermal engineering, meteorology, oceanography, geophysics and astrophysics. It expressly shows how the isomorphism between small and large scale phenomena becomes beneficial to the definition and ensuing development of an integrated comprehensive framework.  This allows the reader to understand and assimilate the underlying, quintessential mechanisms w

  11. Flow Detection Based on Traffic Video Image Processing

    OpenAIRE

    Peng Shen

    2013-01-01

    Because in the traffic video image processing, the background image gotten from background modeling by traditional k-means clustering algorithm shows a lot of noises, thus the improvement of k-means clustering algorithm is proposed, and has been applied to the vehicle flow detection of traffic video image. By analyzing the vehicle detection method and comparing the flow detection algorithm, the improved k-means clustering algorithm is experimentally tested at last, and carries out software im...

  12. Modeling a novel glass immobilization waste treatment process using flow

    International Nuclear Information System (INIS)

    One option for control and disposal of surplus fissile materials is the Glass Material Oxidation and Dissolution System (GMODS), a process developed at ORNL for directly converting Pu-bearing material into a durable high-quality glass waste form. This paper presents a preliminary assessment of the GMODS process flowsheet using FLOW, a chemical process simulator. The simulation showed that the glass chemistry postulated ion the models has acceptable levels of risks

  13. Orbital transfer vehicle launch operations study. Processing flows. Volume 3

    Science.gov (United States)

    1986-01-01

    The Orbit Transfer Vehicle (OTV) processing flow and Resource Identification Sheets (RISs) for the ground based orbit transfer vehicle and for the space based orbit transfer vehicle are the primary source of information for the rest of the Kennedy Space Center (KSC) OTV Launch Operations Study. Work is presented which identifies KSC facility requirements for the OTV Program, simplifies or automates either flow though the application technology, revises test practices and identifies crew sizes or skills used. These flows were used as the primary point of departure from current operations and practices. Analyses results were documented by revising the appropriate RIS page.

  14. Wastewater treatment using electron beam machine - a process flow

    International Nuclear Information System (INIS)

    Electron beam treatment for water and wastewater treatment is being investigated in combination with conventional methods such as biological oxidation, coagulation and ozonization. The application of EBM for wastewater treatment has been carried out by numerous researchers. In ALURTRON, research on the use of Electron Beam Machine for wastewater treatment is still at infancy stage. At the initial stage, effort is being undertaken to develop a process flow for wastewater treatment and water purification. In order to irradiate the water sample, it requires specific apparatus that ensure continuous flow and ideal electron penetration to get uniform beam exposure. This paper presents the proposed process flow mechanism to irradiate and treat wastewater by electron beam irradiation. The process requires an irradiation vessel that consists of irradiation area, water piping, meter, water tank (storage and collection tank), and trolley. (Author)

  15. Flow manipulation and control methodologies for vacuum infusion processes

    Science.gov (United States)

    Alms, Justin B.

    Vacuum Infusion Processes (VIPs) are very attractive composite manufacturing processes since large structures such as fuselages and wind blades can be fabricated in a cost effective manner. In VIPs, the fabric layers are placed on a one sided mold which is closed by enveloping the entire mold with a thin plastic film and evacuating the air out. The vacuum compresses the fabric and when a resin inlet is opened, resin flows into the mold. The resin is allowed to cure before demolding the structure. However, VIPs causes non-repeatable and problematic resin filling patterns due to the heterogeneous nature of the material, nesting between various layers, and the hand labor utilized for laying up the fabric. The design of the manufacturing process routinely involves a trial and error model which make manufacturing costs and development time difficult to estimate. The clear solution to improving the reliability and robustness of VIPs is to implement a system capable of on-line flow control. While on-line flow control has been studied and developed for other composite manufacturing processes, the VIPs have been largely ignored as there are few process parameters that lend themselves to effective flow control. In this work, two new processes were discovered with the goal of on-line control of VIPs in mind. These two processes referred to as Flow Flooding Chamber (FFC) and Vacuum Induced Preform Relaxation (VIPR) will be discussed. They both employ an external vacuum chamber to influence the permeability of the fabric temporarily which allows one to redirect the resin flow to resin starved regions of the mold. The VIPR process in addition uses a low and regulated vacuum pressure in the external chamber to increase the permeability of the fabric in a controllable manner. The objective is to understand how the VIPR process affects the resin flow in order to implement it into a complete flow control and automated environment which will reduce or eliminate the variability experienced. First, the effect on permeability is characterized, so the process can be simulated and the flow front patterns can be predicted. It was found that using the VIPR process in combination with tool side injection gates is a very effective method to control resin flow. Based on this understanding several control algorithms were developed to use the process in an automated manufacturing environment which were tested and validated in a virtual environment. To implement and demonstrate the approach, an experimental workstation was built and various infusion examples were performed in the automated environment to validate the capability of the VIPR process with the control methodologies. The VIPR process with control consistently performed better than the process without control. This contribution should prove useful in making VIPs more reliable in the production of large scale composite structures.

  16. A Stability Diagram for Dense Suspensions of Model Colloidal Al2O3-Particles in Shear Flow

    OpenAIRE

    Hecht, Martin; Harting, Jens; Herrmann, Hans J.

    2006-01-01

    In Al2O3 suspensions, depending on the experimental conditions very different microstructures can be found, comprising fluid like suspensions, a repulsive structure, and a clustered microstructure. For technical processing in ceramics, the knowledge of the microstructure is of importance, since it essentially determines the stability of a workpiece to be produced. To enlighten this topic, we investigate these suspensions under shear by means of simulations. We observe cluste...

  17. Parametric Linear Stochastic Modelling of Benue River flow Process

    Directory of Open Access Journals (Sweden)

    Otache .

    2011-10-01

    Full Text Available The dynamics and accurate forecasting of streamflow processes of a river are important in the management of extreme events such as floods and droughts, optimal design of water storage structures and drainage networks. In this study, attempt was made at investigating the appropriateness of stochastic modelling of the streamflow process of the Benue River using data-driven models based on univariate streamflow series. To this end, multiplicative seasonal Autoregressive Integrated Moving Average (ARIMA model was developed for the logarithmic transformed monthly flows. The seasonal ARIMA model’s performance was compared with the traditional Thomas-Fiering model forecasts, and results obtained show that the multiplicative seasonal ARIMA model was able to forecast flow logarithms. However, it could not adequately account for the seasonal variability in the monthly standard deviations. The forecast flow logarithms therefore cannot readily be transformed into natural flows; hence, the need for cautious optimism in its adoption, though it could be used as a basis for the development of an Integrated Riverflow Forecasting System (IRFS. Since forecasting could be a highly “noisy” application because of the complex river flow system, a distributed hydrological model is recommended for real-time forecasting of the river flow regime especially for purposes of sustainable water resources management.

  18. Shocked similarity collapses and flows in star formation processes

    CERN Document Server

    Shen, Y; Shen, Yue; Lou, Yu-Qing

    2004-01-01

    We propose self-similar shocked flow models for certain dynamical evolution phases of young stellar objects (YSOs), `champagne flows' of H {\\sevenrm II} regions surrounding OB stars and shaping processes of planetary nebulae (PNe). We analyze an isothermal fluid of spherical symmetry and construct families of similarity shocked flow solutions featured by: 1. either a core expansion with a finite central density or a core accretion at constant rate with a density scaling $\\propto r^{-3/2}$; 2. a shock moving outward at a constant speed; 3. a preshock gas approaching a constant speed at large $r$ with a density scaling $\\propto r^{-2}$. In addition to testing numerical codes, our models can accommodate diverse shocked flows with or without a core collapse or outflow and an envelope expansion or contraction. As an application, we introduce our model analysis to observations of Bok globule B335.

  19. Flow modelling of plant processes for fault diagnosis

    International Nuclear Information System (INIS)

    Flow and its interruption or degradation is seen by many people in industry to be the essential problem in fault diagnonsis. It is this observation which has motivated the representation of a complex simulation of a process plant presented here. The display system we have developed represents the mass and energy flow functions of the plant and the relationship between such flow functions. In this report we shall mainly discuss how such representation seems to provide opportunities to design alarm systems as an integral part of the flow function representation itself and to solve two of the most intricate problems in diagnosis, namely the problem of symptom referral and the problem of confuseable faults. (author)

  20. Image processing system for velocity measurements in natural convection flows

    International Nuclear Information System (INIS)

    An image processing system based on a particle-tracking method has been developed to measure quantitatively at one time the two-dimensional velocity components arising in natural convection flows. The analysis of the image data proceeds automatically, due in part to the video recording system utilized in our method. The image processing system was applied to the natural convection flows in a 1/10 scale basic reactor model. The velocity vectors and the vorticities were obtained under transient and steady states in different experimental cases, enabling us to examine in detail the transition of the flow patterns and other aspects under different experimental conditions. The uncertainty of this system was evaluated for use in our experiments and it was confirmed that the margin of error is acceptable. (orig.)

  1. Digital image processing based mass flow rate measurement of gas/solid two-phase flow

    Energy Technology Data Exchange (ETDEWEB)

    Song Ding; Peng Lihui; Lu Geng; Yang Shiyuan [Tsinghua National Laboratory for Information Science and Technology, Department of Automation, Tsinghua University, Beijing, 100084 (China); Yan Yong, E-mail: lihuipeng@tsinghua.edu.c [University of Kent, Canterbury, Kent CT2 7NT (United Kingdom)

    2009-02-01

    With the rapid growth of the process industry, pneumatic conveying as a tool for the transportation of a wide variety of pulverized and granular materials has become widespread. In order to improve plant control and operational efficiency, it is essential to know the parameters of the particle flow. This paper presents a digital imaging based method which is capable of measuring multiple flow parameters, including volumetric concentration, velocity and mass flow rate of particles in the gas/solid two phase flow. The measurement system consists of a solid state laser for illumination, a low-cost CCD camera for particle image acquisition and a microcomputer with bespoke software for particle image processing. The measurements of particle velocity and volumetric concentration share the same sensing hardware but use different exposure time and different image processing methods. By controlling the exposure time of the camera a clear image and a motion blurred image are obtained respectively. The clear image is thresholded by OTSU method to identify the particles from the dark background so that the volumetric concentration is determined by calculating the ratio between the particle area and the total area. Particle velocity is derived from the motion blur length, which is estimated from the motion blurred images by using the travelling wave equation method. The mass flow rate of particles is calculated by combining the particle velocity and volumetric concentration. Simulation and experiment results indicate that the proposed method is promising for the measurement of multiple parameters of gas/solid two-phase flow.

  2. Digital Image Processing in Investigations of Plasma Flow Structure.

    Czech Academy of Sciences Publication Activity Database

    Chumak, Oleksiy; Hrabovský, Milan

    2011-01-01

    Ro?. 39, ?. 11 (2011), s. 2910-2911. ISSN 0093-3813 R&D Projects: GA TA ?R TA01010300 Institutional research plan: CEZ:AV0Z20430508 Keywords : plasma jet * plasma flow fluctuations * image processing Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.174, year: 2011

  3. Discrete time analysis of batch processes in material flow systems

    OpenAIRE

    Schleyer, Marc

    2007-01-01

    Scope of this work is the development of appropriate models for the evaluation of batch processes in material flow systems. The presented analytical methods support the long range planning in an early planning stage, in which capacities are determined to minimize the facility costs under the condition of cycle time targets.

  4. Analysis of flow processes in homogeneous fluids by decomposition into elementary processes

    Energy Technology Data Exchange (ETDEWEB)

    Stosic, Z. (Siemens AG Unternehmensbereich KWU, Erlangen (Germany, F.R.)); Ninic, N. (Institut za Nuklearne Nauke Boris Kidric, Belgrade (Yugoslavia))

    1990-10-01

    A general method for calculation of one-dimensional flows of homogeneous fluids by decomposition into elementary processes is presented. The method, in its more sophisitcated form, finds application in the fields of homogeneous and non-homogeneous flows without work extraction and magneto-hydrodynamic plasma flows, because of its simple calculation procedure without iterations and problems connected to stability and convergence. As an example the procedure was applied to the model of a homogeneous two-phase flow in a boiling saturated fluid. (orig.).

  5. Impact of flow velocity on biochemical processes – a laboratory experiment

    Directory of Open Access Journals (Sweden)

    A. Boisson

    2014-08-01

    Full Text Available Understanding and predicting hydraulic and chemical properties of natural environments are current crucial challenges. It requires considering hydraulic, chemical and biological processes and evaluating how hydrodynamic properties impact on biochemical reactions. In this context, an original laboratory experiment to study the impact of flow velocity on biochemical reactions along a one-dimensional flow streamline has been developed. Based on the example of nitrate reduction, nitrate-rich water passes through plastic tubes at several flow velocities (from 6.2 to 35 mm min?1, while nitrate concentration at the tube outlet is monitored for more than 500 h. This experimental setup allows assessing the biologically controlled reaction between a mobile electron acceptor (nitrate and an electron donor (carbon coming from an immobile phase (tube that produces carbon during its degradation by microorganisms. It results in observing a dynamic of the nitrate transformation associated with biofilm development which is flow-velocity dependent. It is proposed that the main behaviors of the reaction rates are related to phases of biofilm development through a simple analytical model including assimilation. Experiment results and their interpretation demonstrate a significant impact of flow velocity on reaction performance and stability and highlight the relevance of dynamic experiments over static experiments for understanding biogeochemical processes.

  6. Flows of engineered nanomaterials through the recycling process in Switzerland.

    Science.gov (United States)

    Caballero-Guzman, Alejandro; Sun, Tianyin; Nowack, Bernd

    2015-02-01

    The use of engineered nanomaterials (ENMs) in diverse applications has increased during the last years and this will likely continue in the near future. As the number of applications increase, more and more waste with nanomaterials will be generated. A portion of this waste will enter the recycling system, for example, in electronic products, textiles and construction materials. The fate of these materials during and after the waste management and recycling operations is poorly understood. The aim of this work is to model the flows of nano-TiO2, nano-ZnO, nano-Ag and CNT in the recycling system in Switzerland. The basis for this study is published information on the ENMs flows on the Swiss system. We developed a method to assess their flow after recycling. To incorporate the uncertainties inherent to the limited information available, we applied a probabilistic material flow analysis approach. The results show that the recycling processes does not result in significant further propagation of nanomaterials into new products. Instead, the largest proportion will flow as waste that can subsequently be properly handled in incineration plants or landfills. Smaller fractions of ENMs will be eliminated or end up in materials that are sent abroad to undergo further recovery processes. Only a reduced amount of ENMs will flow back to the productive process of the economy in a limited number of sectors. Overall, the results suggest that risk assessment during recycling should focus on occupational exposure, release of ENMs in landfills and incineration plants, and toxicity assessment in a small number of recycled inputs. PMID:25524750

  7. Engineered Barrier System Degradation, Flow, and Transport Process Model Report

    International Nuclear Information System (INIS)

    Performance of a potential Yucca Mountain high-level radioactive waste repository depends on both the natural barrier system (NBS) and the engineered barrier system (EBS) and on their interactions. Although the waste packages are generally considered as components of the EBS, the EBS as defined in the Engineered Barrier System Degradation, Flow, and Transport Process Model Report (PMR), herein referred to as the EBS PMR, includes all engineered components outside the waste packages. Waste packages and waste-form performance is described and modeled in other PMRs. Performance of the drip shield as a means of diverting water is included here, both as-built and following degradation because of various processes. The specific mechanisms and rates of drip shield failure from corrosion and seismic activity are described and modeled in the WP PMR. To evaluate the postclosure performance of a potential repository at Yucca Mountain, a total system performance assessment (TSPA) will be conducted. A set of nine PMRs, of which this document is one, is being developed to summarize the technical basis for each of the process models supporting the TSPA model. These reports cover the following areas: Integrated Site Model; Unsaturated Zone Flow and Transport; Near Field Environment; Engineered Barrier System Degradation, Flow, and Transport; Waste Package Degradation; Waste Form Degradation; Saturated Zone Flow and Transport; Biosphere; and Disruptive Eventsisruptive Events

  8. Features, Events, and Processes in UZ Flow and Transport

    International Nuclear Information System (INIS)

    Unsaturated zone (UZ) flow and radionuclide transport is a component of the natural barriers that affects potential repository performance. The total system performance assessment (TSPA) model, and underlying process models, of this natural barrier component capture some, but not all, of the associated features, events, and processes (FEPs) as identified in the FEPs Database (Freeze, et al. 2001 [154365]). This analysis and model report (AMR) discusses all FEPs identified as associated with UZ flow and radionuclide transport. The purpose of this analysis is to give a comprehensive summary of all UZ flow and radionuclide transport FEPs and their treatment in, or exclusion from, TSPA models. The scope of this analysis is to provide a summary of the FEPs associated with the UZ flow and radionuclide transport and to provide a reference roadmap to other documentation where detailed discussions of these FEPs, treated explicitly in TSPA models, are offered. Other FEPs may be screened out from treatment in TSPA by direct regulatory exclusion or through arguments concerning low probability and/or low consequence of the FEPs on potential repository performance. Arguments for exclusion of FEPs are presented in this analysis. Exclusion of specific FEPs from the UZ flow and transport models does not necessarily imply that the FEP is excluded from the TSPA. Similarly, in the treatment of included FEPs, only the way in which the FEPs are included in the UZ flow and transport models is discussed in this document. This report has been prepared in accordance with the technical work plan for the unsaturated zone subproduct element (CRWMS MandO 2000 [153447]). The purpose of this report is to document that all FEPs are either included in UZ flow and transport models for TSPA, or can be excluded from UZ flow and transport models for TSPA on the basis of low probability or low consequence. Arguments for exclusion are presented in this analysis. Exclusion of specific FEPs from UZ flow and transport models does not necessarily imply that the FEP is excluded from the TSPA. Similarly, in the treatment of included FEPs, only the way in which FEPs are included in UZ flow and transport models is discussed in this document

  9. Features, Events, and Processes in UZ Flow and Transport

    Energy Technology Data Exchange (ETDEWEB)

    J.E. Houseworth

    2001-04-10

    Unsaturated zone (UZ) flow and radionuclide transport is a component of the natural barriers that affects potential repository performance. The total system performance assessment (TSPA) model, and underlying process models, of this natural barrier component capture some, but not all, of the associated features, events, and processes (FEPs) as identified in the FEPs Database (Freeze, et al. 2001 [154365]). This analysis and model report (AMR) discusses all FEPs identified as associated with UZ flow and radionuclide transport. The purpose of this analysis is to give a comprehensive summary of all UZ flow and radionuclide transport FEPs and their treatment in, or exclusion from, TSPA models. The scope of this analysis is to provide a summary of the FEPs associated with the UZ flow and radionuclide transport and to provide a reference roadmap to other documentation where detailed discussions of these FEPs, treated explicitly in TSPA models, are offered. Other FEPs may be screened out from treatment in TSPA by direct regulatory exclusion or through arguments concerning low probability and/or low consequence of the FEPs on potential repository performance. Arguments for exclusion of FEPs are presented in this analysis. Exclusion of specific FEPs from the UZ flow and transport models does not necessarily imply that the FEP is excluded from the TSPA. Similarly, in the treatment of included FEPs, only the way in which the FEPs are included in the UZ flow and transport models is discussed in this document. This report has been prepared in accordance with the technical work plan for the unsaturated zone subproduct element (CRWMS M&O 2000 [153447]). The purpose of this report is to document that all FEPs are either included in UZ flow and transport models for TSPA, or can be excluded from UZ flow and transport models for TSPA on the basis of low probability or low consequence. Arguments for exclusion are presented in this analysis. Exclusion of specific FEPs from UZ flow and transport models does not necessarily imply that the FEP is excluded from the TSPA. Similarly, in the treatment of included FEPs, only the way in which FEPs are included in UZ flow and transport models is discussed in this document.

  10. On-line sample processing methods in flow analysis

    DEFF Research Database (Denmark)

    Miró, Manuel; Hansen, Elo Harald

    2008-01-01

    In this chapter, the state of the art of flow injection and related approaches thereof for automation and miniaturization of sample processing regardless of the aggregate state of the sample medium is overviewed. The potential of the various generation of flow injection for implementation of in-line dilution, derivatization, separation and preconcentration methods encompassing solid reactors, solvent extraction, sorbent extraction, precipitation/coprecipitation, hydride/vapor generation and digestion/leaching protocols as hyphenated to a plethora of detection devices is discussed in detail and relevant examples published in the literature up to April 2007 are pinpointed.

  11. Prolog Visualization System Using Logichart Diagrams

    OpenAIRE

    Adachi, Yoshihiro

    2009-01-01

    We have developed a Prolog visualization system that is intended to support Prolog programming education. The system uses Logichart diagrams to visualize Prolog programs. The Logichart diagram is designed to visualize the Prolog execution flow intelligibly and to enable users to easily correlate the Prolog clauses with its parts. The system has the following functions. (1) It visually traces Prolog execution (goal calling, success, and failure) on the Logichart diagram. (2) ...

  12. Flow Detection Based on Traffic Video Image Processing

    Directory of Open Access Journals (Sweden)

    Peng Shen

    2013-10-01

    Full Text Available Because in the traffic video image processing, the background image gotten from background modeling by traditional k-means clustering algorithm shows a lot of noises, thus the improvement of k-means clustering algorithm is proposed, and has been applied to the vehicle flow detection of traffic video image. By analyzing the vehicle detection method and comparing the flow detection algorithm, the improved k-means clustering algorithm is experimentally tested at last, and carries out software implementation. The experiment shows that the improved algorithm after background modeling is superior to the traditional one in time complexity, it has better adaptivity and robustness, which has increased the effect of vehicle flow detection.

  13. Multilevel flow modelling of process plant for diagnosis and control

    International Nuclear Information System (INIS)

    The paper describes the multilevel flow modelling methodology which can be used to construct functional models of energy and material processing systems. The models describe mass and energy flow topology on different levels of abstraction and represent the hierarchical functional structure of complex systems. A model of a nuclear power plant (PWR) is presented in the paper for illustration. Due to the consistency of the method, multilevel flow models provide specifications of plant goals and functions and may be used as a basis for design of computer-based support systems for the plant operator. Plant control requirements can be derived from the models and due to independence of the actual controller implementation the method may be used as a basis for design of control strategies and for the allocation of control tasks to the computer and the plant operator

  14. Multilevel Flow Modelling of Process Plant for Diagnosis and Control

    DEFF Research Database (Denmark)

    Lind, Morten

    1982-01-01

    The paper describes the multilevel flow modelling methodology which can be used to construct functional models of energy and material processing systems. The models describe mass and energy flow topology on different levels of abstraction and represent the hierarchical functional structure of complex systems. A model of a nuclear power plant (PWR) is presented in the paper for illustration. Due to the consistency of the method, multilevel flow models provide specifications of plant goals and functions and may be used as a basis for design of computer-based support systems for the plant operator. Plant control requirements can be derived from the models and due to independence of the actual controller implementation the method may be used as a basis for design of control strategies and for the allocation of control tasks to the computer and the plant operator.

  15. Recharge and flow processes in a till aquitard

    DEFF Research Database (Denmark)

    SchrØder, Thomas Morville; HØgh Jensen, Karsten

    1999-01-01

    Eastern Denmark is primarily covered by clay till. The transformation of the excess rainfall into laterally diverted groundwater flow, drain flow, stream flow, and recharge to the underlying aquifer is governed by complicatedinterrelated processes. Distributed hydrological models provide a framework for assessing the individual flow components and forestablishing the overall water balance. Traditionally such models are calibrated against measurements of stream flow, head in the aquiferand perhaps drainage flow. The head in the near surface clay till deposits have generally not been measured and therefore not consideredin the calibration procedure.In a 16 km2 rural catchment, 15 shallow wells were installed in the upstream end for continuous measurements of the fluctuations in hydraulic head. In addition data were obtained from two wells penetrating to the deeper artesian aquifer, one located near the shallow wells and one in the valley adjacent to the stream. Precipitation and stream flow gauging along with potential evaporation estimates from a nearby weather station provide the basic data for the overall water balance assessment. The geological composition was determined from geoelectrical surveys along three transects, supported by geophysical logs in deepwells, lowflow records at the outlet of the catchment and three tributaries, and soil maps. Slug tests were carried to obtain data forhydraulic conductivity.The time series of hydraulic head depth in the shallow wells were analyzed using linear transfer noise functions on driving input timeseries and kriging techniques in order to identify correlation structures in time and space among the wells.The distributed and physically based hydrological model code MIKE SHE was applied to the catchment. The model considers one-dimensional flow in the unsaturated zone and three-dimensional below. Drainage flow isempirically modelled as a linear reservoir using a time constant related to drain pipe capacity, spacing and soil hydraulic conductivity.Key parameters are calibrated against records of precipitation, potential evaporation and stream flow. Simulation based on historicalrecords prior to the installation of subsurface drainage in 1/3 of the catchment was carried out in order to investigate the impact ofdrainage on streamflow and access the use of the linear reservoir assumption. Subsequently, data from the shallow wells wereconsidered in order to analyse the value of such data in the calibration procedure and particularly in estimating the areal variation inrecharge.

  16. Process flow innovations for photonic device integration in CMOS

    Science.gov (United States)

    Beals, Mark; Michel, J.; Liu, J. F.; Ahn, D. H.; Sparacin, D.; Sun, R.; Hong, C. Y.; Kimerling, L. C.; Pomerene, A.; Carothers, D.; Beattie, J.; Kopa, A.; Apsel, A.; Rasras, M. S.; Gill, D. M.; Patel, S. S.; Tu, K. Y.; Chen, Y. K.; White, A. E.

    2008-02-01

    Multilevel thin film processing, global planarization and advanced photolithography enables the ability to integrate complimentary materials and process sequences required for high index contrast photonic components all within a single CMOS process flow. Developing high performance photonic components that can be integrated with electronic circuits at a high level of functionality in silicon CMOS is one of the basic objectives of the EPIC program sponsored by the Microsystems Technology Office (MTO) of DARPA. Our research team consisting of members from: BAE Systems, Alcatel-Lucent, Massachusetts Institute of Technology, Cornell University and Applied Wave Research reports on the latest developments of the technology to fabricate an application specific, electronic-photonic integrated circuit (AS_EPIC). Now in its second phase of the EPIC program, the team has designed, developed and integrated fourth order optical tunable filters, both silicon ring resonator and germanium electro-absorption modulators and germanium pin diode photodetectors using silicon waveguides within a full 150nm CMOS process flow for a broadband RF channelizer application. This presentation will review the latest advances of the passive and active photonic devices developed and the processes used for monolithic integration with CMOS processing. Examples include multilevel waveguides for optical interconnect and germanium epitaxy for active photonic devices such as p-i-n photodiodes and modulators.

  17. Preface "Nonlinear processes in oceanic and atmospheric flows"

    CERN Document Server

    Mancho, A M; Turiel, A; Hernandez-Garcia, E; Lopez, C; Garcia-Ladona, E; 10.5194/npg-17-283-2010

    2010-01-01

    Nonlinear phenomena are essential ingredients in many oceanic and atmospheric processes, and successful understanding of them benefits from multidisciplinary collaboration between oceanographers, meteorologists, physicists and mathematicians. The present Special Issue on ``Nonlinear Processes in Oceanic and Atmospheric Flows'' contains selected contributions from attendants to the workshop which, in the above spirit, was held in Castro Urdiales, Spain, in July 2008. Here we summarize the Special Issue contributions, which include papers on the characterization of ocean transport in the Lagrangian and in the Eulerian frameworks, generation and variability of jets and waves, interactions of fluid flow with plankton dynamics or heavy drops, scaling in meteorological fields, and statistical properties of El Ni\\~no Southern Oscillation.

  18. Cerebral blood flow and mental processes in schizophrenia.

    OpenAIRE

    Liddle, P. F.; Friston, K. J.; Frith, C. D.; Frackowiak, R. S.

    1992-01-01

    The patterns of cerebral blood flow associated with three syndromes of schizophrenic symptoms are compared with the loci of cerebral activation in normal subjects during the performance of mental processes implicated in the three syndromes. The psychomotor poverty syndrome, which has been shown to involve a diminished ability to generate words, is associated with decreased perfusion of the dorsolateral prefrontal cortex at a locus which is activated in normal subjects during the internal gene...

  19. FORTES: Forensic Information Flow Analysis of Business Processes

    OpenAIRE

    Accorsi, Rafael; Mu?ller, Gu?nter

    2010-01-01

    Nearly 70% of all business processes in use today rely on automated workflow systems for their execution. Despite the growing expenses in the design of advanced tools for secure and compliant deployment of workflows, an exponential growth of dependability incidents persists. Concepts beyond access control focusing on information flow control offer new paradigms to design security mechanisms for reliable and secure IT-based workflows. This talk presents FORTES, an approach for the forensic...

  20. Coded Ultrasound for Blood Flow Estimation Using Subband Processing

    OpenAIRE

    Gran, Fredrik; Udesen, Jesper; Nielsen, Michael Bachamnn; Jensen, Jørgen Arendt

    2008-01-01

    This paper investigates the use of coded excitation for blood flow estimation in medical ultrasound. Traditional autocorrelation estimators use narrow-band excitation signals to provide sufficient signal-to-noise-ratio (SNR) and velocity estimation performance. In this paper, broadband coded signals are used to increase SNR, followed by subband processing. The received broadband signal is filtered using a set of narrow-band filters. Estimating the velocity in each of the bands and averaging t...

  1. Ground-state phase diagram and magnetization process of the exactly solved mixed spin-(1,1/2) Ising diamond chain

    International Nuclear Information System (INIS)

    The ground state and magnetization process of the mixed spin-(1,1/2) Ising diamond chain are exactly solved by employing the generalized decoration–iteration mapping transformation and the transfer-matrix method. The decoration–iteration transformation is first used in order to establish a rigorous mapping equivalence with the corresponding spin-1 Blume-Emery-Griffiths chain in a non-zero magnetic field, which is subsequently exactly treated within the framework of the transfer-matrix technique. It is shown that the ground-state phase diagram includes just four different ground states and the low-temperature magnetization curve may exhibit an intermediate plateau precisely at one half of the saturation magnetization. Our rigorous results disprove recent Monte Carlo simulations of Xin et al. [Z. Xin, S. Chen, C. Zhang, J. Magn. Magn. Mater. 324 (2012) 3704], which imply an existence of the other magnetization plateaus at 0.283 and 0.426 of the saturation magnetization. - Highlights: • Mixed spin-(1,1/2) Ising diamond chain is exactly solved. • Ground-state phase diagram consists of four different phases. • Magnetization plateaus at zero and half of the saturation magnetization were found

  2. Method and apparatus for measuring coupled flow, transport, and reaction processes under liquid unsaturated flow conditions

    Science.gov (United States)

    McGrail, Bernard P. (Pasco, WA); Martin, Paul F. (Richland, WA); Lindenmeier, Clark W. (Richland, WA)

    1999-01-01

    The present invention is a method and apparatus for measuring coupled flow, transport and reaction processes under liquid unsaturated flow conditions. The method and apparatus of the present invention permit distinguishing individual precipitation events and their effect on dissolution behavior isolated to the specific event. The present invention is especially useful for dynamically measuring hydraulic parameters when a chemical reaction occurs between a particulate material and either liquid or gas (e.g. air) or both, causing precipitation that changes the pore structure of the test material.

  3. The investigate of flow in direct extrusion process of heterogeneous materials flow

    Directory of Open Access Journals (Sweden)

    A. Patejuk

    2007-04-01

    Full Text Available The results of experimental investigations were introduced in range of verification of model investigations results (in utilization of supplementary materials with results of investigations on real materials are presented in this work. To this aim the matrix became constructed with interchangeable little eye made possible extrusion process of real materials at three reduction ratio: ? = 1,5 1,75 and 2,0. Analysis of heterogeneous materials flow process shows, that of principle onto extrusion process exerts kind as well as a way distribution of entrance creators' materials batch. However size of strength of stamp pressure is determined by reduction ratio in main measure

  4. Flow effects on benthic stream invertebrates and ecological processes

    Science.gov (United States)

    Koprivsek, Maja; Brilly, Mitja

    2010-05-01

    Flow is the main abiotic factor in the streams. Flow affects the organisms in many direct and indirect ways. The organisms are directly affected by various hydrodynamic forces and mass transfer processes like drag forces, drift, shear stress, food and gases supply and washing metabolites away. Indirect effects on the organisms are determining and distribution of the particle size and structure of the substrate and determining the morphology of riverbeds. Flow does not affect only on individual organism, but also on many ecological effects. To expose just the most important: dispersal of the organisms, habitat use, resource acquisition, competition and predator-prey interactions. Stream invertebrates are adapted to the various flow conditions in many kinds of way. Some of them are avoiding the high flow with living in a hyporeic zone, while the others are adapted to flow with physical adaptations (the way of feeding, respiration, osmoregulation and resistance to draught), morphological adaptations (dorsoventrally flattened shape of organism, streamlined shape of organism, heterogeneous suckers, silk, claws, swimming hair, bristles and ballast gravel) or with behaviour. As the flow characteristics in a particular stream vary over a broad range of space and time scales, it is necessary to measure accurately the velocity in places where the organisms are present to determine the actual impact of flow on aquatic organisms. By measuring the mean flow at individual vertical in a single cross-section, we cannot get any information about the velocity situation close to the bottom of the riverbed where the stream invertebrates are living. Just measuring the velocity near the bottom is a major problem, as technologies for measuring the velocity and flow of natural watercourses is not adapted to measure so close to the bottom. New researches in the last two decades has shown that the thickness of laminar border layer of stones in the stream is only a few 100 micrometers, what is not enough to make a shelter for stream invertebrates. It serves as a shelter only for microorganisms, but the stream invertebrates have to avoid the swift flow or adapt to flow with adaptations described above. To understand what conditions are subject to aquatic organisms and how to adapt, it is essential. Both, knowledge of fluid dynamics in natural watercourses and ecology are needed to understand to what conditions the stream invertebrates are exposed and how they cope with them. Some investigations of near bed flow will be performed on the Glinšica stream. The acoustic Doppler velocimeter SonTek will be adapted to measure so close to the bed as possible. It is expected we should be able to measure the velocities just 0,5 cm above the bed surface. We intend to measure the velocities on a natural and on a regulated reach and then compare the results.

  5. Numerical Modeling of Fluid Flow in the Tape Casting Process

    Science.gov (United States)

    Jabbari, Masoud; Hattel, Jesper

    2011-09-01

    The flow behavior of the fluid in the tape casting process is analyzed. A simple geometry is assumed for running the numerical calculations in ANSYS Fluent and the main parameters are expressed in non-dimensional form. The effect of different values for substrate velocity and pressure force on the flow pattern as well as resultant tape thickness is evaluated. The analysis deals with the case of parallel blades and focuses on the ratio between the present hydrostatic pressure and the magnitude of the viscous force. A new non-dimensional height for the tape thickness is proposed and the effect of the substrate velocity is evaluated. The results of the modeling show that a relatively uniform tape thickness can be achieved. Moreover, the results are compared with selected experimental and analytical data from literature and good agreement is found.

  6. Effects of air flow directions on composting process temperature profile

    International Nuclear Information System (INIS)

    In this study, chicken manure mixed with carnation wastes was composted by using three different air flow directions: R1-sucking (downward), R2-blowing (upward) and R3-mixed. The aim was to find out the most appropriate air flow direction type for composting to provide more homogenous temperature distribution in the reactors. The efficiency of each aeration method was evaluated by monitoring the evolution of parameters such as temperature, moisture content, CO2 and O2 ratio in the material and dry material losses. Aeration of the reactors was managed by radial fans. The results showed that R3 resulted in a more homogenous temperature distribution and high dry material loss throughout the composting process. The most heterogeneous temperature distribution and the lowest dry material loss were obtained in R2

  7. Numerical Modeling of Fluid Flow in the Tape Casting Process

    DEFF Research Database (Denmark)

    Jabbari, Masoud; Hattel, Jesper Henri

    2011-01-01

    The flow behavior of the fluid in the tape casting process is analyzed. A simple geometry is assumed for running the numerical calculations in ANSYS Fluent and the main parameters are expressed in non-dimensional form. The effect of different values for substrate velocity and pressure force on the flow pattern as well as resultant tape thickness is evaluated. The analysis deals with the case of parallel blades and focuses on the ratio between the present hydrostatic pressure and the magnitude of the viscous force. A new non-dimensional height for the tape thickness is proposed and the effect of the substrate velocity is evaluated. The results of the modeling show that a relatively uniform tape thickness can be achieved. Moreover, the results are compared with selected experimental and analytical data from literature and good agreement is found.

  8. Information Flow and Data Reduction in the ECG Interpretation Process.

    Science.gov (United States)

    Tadeusiewicz, Ryszard; Augustyniak, Piotr

    2005-01-01

    In result of ECG interpretation process the diagnostic outcome summarizes all the principal information included in the raw recording. This process is investigated in this paper in data flow and data reduction aspects being of particular impotrance for implementation of distributed ECG interpretation in a wireless network. The detailed analysis of existing software and cardiologists societies guidelines reduces the whole interpretation process to the network of modules interconnected by data busses. Each module is then described by the computational reliability and by expected data streams at its inputs and outputs, from which the average data reduction ratio is computed. These parameters are consequently used for a design of interpretation architecture improving the diagnostic reliability and oriented to appropriate task sharing between the remote wearable recorder and the interpretive center. PMID:17282194

  9. Post-processing methods of PIV instantaneous flow fields for unsteady flows in turbomachines

    OpenAIRE

    Cavazzini, Giovanna; Dazin, Antoine; Pavesi, Giorgio; Dupont, Patrick; Bois, Ge?rard

    2012-01-01

    The Particle Image Velocimetry is undoubtedly one of the most important technique in Fluid-dynamics since it allows to obtain a direct and instantaneous visualization of the flow field in a non-intrusive way. This innovative technique spreads in a wide number of research fields, from aerodynamics to medicine, from biology to turbulence researches, from aerodynamics to combustion processes. The book is aimed at presenting the PIV technique and its wide range of possible applications so as to p...

  10. Process and device for frequency-controlled flow measurement by the acceleration pressure process

    International Nuclear Information System (INIS)

    In order to measure speed, flow and outflow in a compressible flow, particularly for very transient events in at least two places behind one another in the direction of flow in the pipe, pressure gauges are situated, by which the pressure is measured at equal time intervals. The time interval between two measurements is less than or equal to the distance between the pressure sensors, divided by the speed of sound. The measurements are processed by electronic circuits to solve the non-steady state flow equation of compressible media. If the speed of sound varies, then by expanding the device by an additional pressure sensor, the speed of sound can be determined, which value is then used in the evaluation. (orig./HP)

  11. A continuous-flow process for the synthesis of artemisinin.

    Science.gov (United States)

    Kopetzki, Daniel; Lévesque, François; Seeberger, Peter H

    2013-04-22

    Isolation of the most effective antimalarial drug, artemisinin, from the plant sweet wormwood, does not yield sufficient quantities to provide the more than 300 million treatments needed each year. The high prices for the drug are a consequence of the unreliable and often insufficient supply of artemisinin. Large quantities of ineffective fake drugs find a market in Africa. Semisynthesis of artemisinin from inactive biological precursors, either dihydroartemisinic acid (DHAA) or artemisinic acid, offers a potentially attractive route to increase artemisinin production. Conversion of the plant waste product, DHAA, into artemisinin requires use of photochemically generated singlet oxygen at large scale. We met this challenge by developing a one-pot photochemical continuous-flow process for the semisynthesis of artemisinin from DHAA that yields 65?% product. Careful optimization resulted in a process characterized by short residence times. A method to extract DHAA from the mother liquor accumulated during commercial artemisinin extractions, a material that is currently discarded as waste, is also reported. The synthetic continuous-flow process described here is an effective means to supplement the limited availability of artemisinin and ensure increased supplies of the drug for those in need. PMID:23520059

  12. Work diagram for plutonium

    International Nuclear Information System (INIS)

    Predominance region diagrams, as guides to the chemistries of elements in solutions, are described, with reference to the potential-pH diagram. A description is now given of free energy-pH diagrams (referred to as work diagrams). A work diagram for aqueous plutonium is presented, showing how much work must be expended upon one liter of a solution containing one millimole of plutonium, initially in the trivalent state, in order to convert it into some other oxidation state distribution in which another oxidation state predominates. Methods of preparing the diagram, and the thermodynamics involved, are discussed. (U.K.)

  13. Safety- barrier diagrams

    DEFF Research Database (Denmark)

    Duijm, Nijs Jan

    2008-01-01

    Safety-barrier diagrams and the related so-called 'bow-tie' diagrams have become popular methods in risk analysis. This paper describes the syntax and principles for constructing consistent and valid safety-barrier diagrams. The relation of safety-barrier diagrams to other methods such as fault trees and Bayesian networks is discussed. A simple method for quantification of safety-barrier diagrams is proposed. It is concluded that safety-barrier diagrams provide a useful framework for an electronic data structure that integrates information from risk analysis with operational safety management.

  14. Microfluidic-SANS: flow processing of complex fluids.

    Science.gov (United States)

    Lopez, Carlos G; Watanabe, Takaichi; Martel, Anne; Porcar, Lionel; Cabral, João T

    2015-01-01

    Understanding and engineering the flow-response of complex and non-Newtonian fluids at a molecular level is a key challenge for their practical utilisation. Here we demonstrate the coupling of microfluidics with small angle neutron scattering (SANS). Microdevices with high neutron transmission (up to 98%), low scattering background (?10?² cm?¹), broad solvent compatibility and high pressure tolerance (?3-15 bar) are rapidly prototyped via frontal photo polymerisation. Scattering from single microchannels of widths down to 60??m, with beam footprint of 500??m diameter, was successfully obtained in the scattering vector range 0.01-0.3?Å(-1), corresponding to real space dimensions of ?10-600 Å. We demonstrate our approach by investigating the molecular re-orientation and alignment underpinning the flow response of two model complex fluids, namely cetyl trimethylammonium chloride/pentanol/D?O and sodium lauryl sulfate/octanol/brine lamellar systems. Finally, we assess the applicability and outlook of microfluidic-SANS for high-throughput and flow processing studies, with emphasis of soft matter. PMID:25578326

  15. Microfluidic-SANS: flow processing of complex fluids

    Science.gov (United States)

    Lopez, Carlos G.; Watanabe, Takaichi; Martel, Anne; Porcar, Lionel; Cabral, João T.

    2015-01-01

    Understanding and engineering the flow-response of complex and non-Newtonian fluids at a molecular level is a key challenge for their practical utilisation. Here we demonstrate the coupling of microfluidics with small angle neutron scattering (SANS). Microdevices with high neutron transmission (up to 98%), low scattering background (), broad solvent compatibility and high pressure tolerance (?3–15 bar) are rapidly prototyped via frontal photo polymerisation. Scattering from single microchannels of widths down to 60??m, with beam footprint of 500??m diameter, was successfully obtained in the scattering vector range 0.01–0.3?Å?1, corresponding to real space dimensions of . We demonstrate our approach by investigating the molecular re-orientation and alignment underpinning the flow response of two model complex fluids, namely cetyl trimethylammonium chloride/pentanol/D2O and sodium lauryl sulfate/octanol/brine lamellar systems. Finally, we assess the applicability and outlook of microfluidic-SANS for high-throughput and flow processing studies, with emphasis of soft matter. PMID:25578326

  16. Coded Ultrasound for Blood Flow Estimation Using Subband Processing

    DEFF Research Database (Denmark)

    Gran, Fredrik; Udesen, Jesper

    2008-01-01

    This paper investigates the use of coded excitation for blood flow estimation in medical ultrasound. Traditional autocorrelation estimators use narrow-band excitation signals to provide sufficient signal-to-noise-ratio (SNR) and velocity estimation performance. In this paper, broadband coded signals are used to increase SNR, followed by subband processing. The received broadband signal is filtered using a set of narrow-band filters. Estimating the velocity in each of the bands and averaging the results yields better performance compared with what would be possible when transmitting a narrow-band pulse directly. Also, the spatial resolution of the narrow-band pulse would be too poor for brightness-mode (B-mode) imaging, and additional transmissions would be required to update the B-mode image. For the described approach in the paper, there is no need for additional transmissions, because the excitation signal is broadband and has good spatial resolution after pulse compression. This means that time can be saved by using the same data for B-mode imaging and blood flow estimation. Two different coding schemes are used in this paper, Barker codes and Golay codes. The performance of the codes for velocity estimation is compared with a conventional approach transmitting a narrow-band pulse. The study was carried out using an experimental ultrasound scanner and a commercial linear array 7 MHz transducer. A circulating flow rig was scanned with a beam-to-flow angle of 60°. The flow in the rig was laminar and had a parabolic flow-profile with a peak velocity of 0.09 m/s. The mean relative standard deviation of the velocity estimate using the reference method with an 8-cycle excitation pulse at 7 MHz was 0.544% compared with the peak velocity in the rig. Two Barker codes were tested with a length of 5 and 13 bits, respectively. The corresponding mean relative standard deviations were 0.367% and 0.310%, respectively. For the Golay coded experiment, two 8-bit codes were used, and the mean relative standard deviation was 0.335%.

  17. Features, Events and Processes in UZ Flow and Transport

    Energy Technology Data Exchange (ETDEWEB)

    P. Persoff

    2005-08-04

    The purpose of this report is to evaluate and document the inclusion or exclusion of the unsaturated zone (UZ) features, events, and processes (FEPs) with respect to modeling that supports the total system performance assessment (TSPA) for license application (LA) for a nuclear waste repository at Yucca Mountain, Nevada. A screening decision, either Included or Excluded, is given for each FEP, along with the technical basis for the screening decision. This information is required by the U.S. Nuclear Regulatory Commission (NRC) in 10 CFR 63.114 (d, e, and f) [DIRS 173273]. The FEPs deal with UZ flow and radionuclide transport, including climate, surface water infiltration, percolation, drift seepage, and thermally coupled processes. This analysis summarizes the implementation of each FEP in TSPA-LA (that is, how the FEP is included) and also provides the technical basis for exclusion from TSPA-LA (that is, why the FEP is excluded). This report supports TSPA-LA.

  18. Flow process for electroextraction of total proteins from microalgae.

    Science.gov (United States)

    Coustets, M; Al-Karablieh, N; Thomsen, C; Teissié, J

    2013-10-01

    Classical methods for protein extraction from microorganisms, used for large-scale treatments such as mechanical or chemical processes, affect the integrity of extracted cytosolic protein by releasing proteases contained in vacuoles. Our previous experiments on flow-process yeast electroextraction proved that pulsed electric field technology allows us to preserve the integrity of released cytosolic proteins by keeping intact vacuole membranes. Furthermore, large volumes are easily treated by the flow technology. Based on this previous knowledge, we developed a new protocol in order to electroextract total cytoplasmic proteins from microalgae (Nannochloropsis salina and Chlorella vulgaris). Given that induction of electropermeabilization is under the control of the target cell size, as the mean diameter for N. salina is only 2.5 ?m, we used repetitive 2-ms-long pulses of alternating polarities with stronger field strengths than previously described for yeasts. The electric treatment was followed by a 24-h incubation period in a salty buffer. The amount of total protein released was evaluated by a classical Bradford assay. A more accurate evaluation of protein release was obtained by SDS-PAGE. Similar results were obtained with C. vulgaris under milder electrical conditions, as expected from their larger size. This innovative technology designed in our group should become familiar in the field of microalgae biotechnology. PMID:23575984

  19. Modelling of energy flows in potato crisp frying processes

    International Nuclear Information System (INIS)

    Food frying is very energy intensive and in industrial potato crisp production lines frying is responsible for more than 90% of the total energy consumption of the process. This paper considers the energy flows in crisp frying using a First Law of Thermodynamics modelling approach which was verified against data from a potato crisp production line. The results indicate that for the frying process considered, most of the energy used is associated with the evaporation of water present in the potato and on the surface of potato slices. The remainder is from evaporation of frying oil and air of the ventilation system and heat losses from the fryer wall surfaces by convection and radiation. The frying oil is heated by an industrial gas furnace and the efficiency of this process was calculated to be 84%. The efficiency of the overall frying process which was found to be of the order of 70% can be improved by employing exhaust heat recovery and optimising other operating and control parameters such as exhaust gas recirculation.

  20. Hyporheic flow and transport processes: Mechanisms, models, and biogeochemical implications

    Science.gov (United States)

    Boano, F.; Harvey, J. W.; Marion, A.; Packman, A. I.; Revelli, R.; Ridolfi, L.; Wörman, A.

    2014-12-01

    Fifty years of hyporheic zone research have shown the important role played by the hyporheic zone as an interface between groundwater and surface waters. However, it is only in the last two decades that what began as an empirical science has become a mechanistic science devoted to modeling studies of the complex fluid dynamical and biogeochemical mechanisms occurring in the hyporheic zone. These efforts have led to the picture of surface-subsurface water interactions as regulators of the form and function of fluvial ecosystems. Rather than being isolated systems, surface water bodies continuously interact with the subsurface. Exploration of hyporheic zone processes has led to a new appreciation of their wide reaching consequences for water quality and stream ecology. Modern research aims toward a unified approach, in which processes occurring in the hyporheic zone are key elements for the appreciation, management, and restoration of the whole river environment. In this unifying context, this review summarizes results from modeling studies and field observations about flow and transport processes in the hyporheic zone and describes the theories proposed in hydrology and fluid dynamics developed to quantitatively model and predict the hyporheic transport of water, heat, and dissolved and suspended compounds from sediment grain scale up to the watershed scale. The implications of these processes for stream biogeochemistry and ecology are also discussed.

  1. Process Modeling of Flow, Transport, and Biodegradation in Landfill Bioreactors

    Science.gov (United States)

    Oldenburg, C. M.; Borglin, S. E.; Hazen, T. C.

    2001-12-01

    The need to control gas and leachate production and minimize refuse volume has motivated laboratory experiments and model development for design and assessment of bioremediation treatment processes. In parallel with landfill bioreactor laboratory experiments, we have developed T2LBM, a module for the TOUGH2 multiphase flow and transport simulator that implements a Landfill Bioreactor Model. T2LBM provides simulation capability for the processes of aerobic or anaerobic biodegradation of municipal solid waste and the associated three-dimensional flow and transport of gas, liquid, and heat through the refuse mass. T2LBM considers the components water, acetic acid, carbon dioxide, methane, oxygen, and nitrogen in aqueous and gas phases, with partitioning specified by temperature-dependent Henry's coefficients. T2LBM incorporates a Monod kinetic rate law for the exothermic biodegradation of acetic acid in the aqueous phase by either aerobic or anaerobic microbes as controlled by the local oxygen concentration. Methane and carbon dioxide generation due to biodegradation with corresponding thermal effects are modeled. Acetic acid is considered a proxy for all biodegradable substrates in the refuse. Aerobic and anaerobic microbes are assumed to be immobile and not limited by nutrients in their growth. Although a simplification of complex landfill processes, T2LBM shows reasonable agreement to published laboratory experiments of biodegradation and gas production depending on the choice of numerous input parameters. Simulations of the landfill bioreactor laboratory experiments show that the mechanistic approach of T2LBM can be used to model bioremediation assessment indicators such as oxygen consumption associated with respiration tests. This work was supported by Laboratory Directed Research and Development Funds at Lawrence Berkeley National Laboratory under Department of Energy Contract No. DE-AC03-76SF00098.

  2. Engineered Barrier System Degradation, Flow, and Transport Process Model Report

    Energy Technology Data Exchange (ETDEWEB)

    E.L. Hardin

    2000-07-17

    The Engineered Barrier System Degradation, Flow, and Transport Process Model Report (EBS PMR) is one of nine PMRs supporting the Total System Performance Assessment (TSPA) being developed by the Yucca Mountain Project for the Site Recommendation Report (SRR). The EBS PMR summarizes the development and abstraction of models for processes that govern the evolution of conditions within the emplacement drifts of a potential high-level nuclear waste repository at Yucca Mountain, Nye County, Nevada. Details of these individual models are documented in 23 supporting Analysis/Model Reports (AMRs). Nineteen of these AMRs are for process models, and the remaining 4 describe the abstraction of results for application in TSPA. The process models themselves cluster around four major topics: ''Water Distribution and Removal Model, Physical and Chemical Environment Model, Radionuclide Transport Model, and Multiscale Thermohydrologic Model''. One AMR (Engineered Barrier System-Features, Events, and Processes/Degradation Modes Analysis) summarizes the formal screening analysis used to select the Features, Events, and Processes (FEPs) included in TSPA and those excluded from further consideration. Performance of a potential Yucca Mountain high-level radioactive waste repository depends on both the natural barrier system (NBS) and the engineered barrier system (EBS) and on their interactions. Although the waste packages are generally considered as components of the EBS, the EBS as defined in the EBS PMR includes all engineered components outside the waste packages. The principal function of the EBS is to complement the geologic system in limiting the amount of water contacting nuclear waste. A number of alternatives were considered by the Project for different EBS designs that could provide better performance than the design analyzed for the Viability Assessment. The design concept selected was Enhanced Design Alternative II (EDA II).

  3. Safety-barrier diagrams

    DEFF Research Database (Denmark)

    Duijm, Nijs Jan

    2007-01-01

    Safety-barrier diagrams and the related so-called "bow-tie" diagrams have become popular methods in risk analysis. This paper describes the syntax and principles for constructing consistent and valid safety-barrier diagrams. The relation with other methods such as fault trees and Bayesian networks are discussed. A simple method for quantification of safety-barrier diagrams is proposed, including situations where safety barriers depend on shared common elements. It is concluded that safety-barrier diagrams provide a useful framework for an electronic data structure that integrates information from risk analysis with operational safety management.

  4. Features, Events, and Processes in SZ Flow and Transport

    Energy Technology Data Exchange (ETDEWEB)

    S. Kuzio

    2005-08-20

    This analysis report evaluates and documents the inclusion or exclusion of the saturated zone (SZ) features, events, and processes (FEPs) with respect to modeling used to support the total system performance assessment (TSPA) for license application (LA) of a nuclear waste repository at Yucca Mountain, Nevada. A screening decision, either Included or Excluded, is given for each FEP along with the technical basis for the decision. This information is required by the U.S. Nuclear Regulatory Commission (NRC) at 10 CFR 63.11(d), (e), (f) [DIRS 173273]. This scientific report focuses on FEP analysis of flow and transport issues relevant to the SZ (e.g., fracture flow in volcanic units, anisotropy, radionuclide transport on colloids, etc.) to be considered in the TSPA model for the LA. For included FEPs, this analysis summarizes the implementation of the FEP in TSPA-LA (i.e., how the FEP is included). For excluded FEPs, this analysis provides the technical basis for exclusion from TSPA-LA (i.e., why the FEP is excluded).

  5. Features, Events, and Processes in SZ Flow and Transport

    Energy Technology Data Exchange (ETDEWEB)

    K. Economy

    2004-11-16

    This analysis report evaluates and documents the inclusion or exclusion of the saturated zone (SZ) features, events, and processes (FEPs) with respect to modeling used to support the total system performance assessment (TSPA) for license application (LA) of a nuclear waste repository at Yucca Mountain, Nevada. A screening decision, either ''Included'' or ''Excluded'', is given for each FEP along with the technical basis for the decision. This information is required by the U.S. Nuclear Regulatory Commission (NRC) at 10 CFR 63.114 (d), (e), (f) (DIRS 156605). This scientific report focuses on FEP analysis of flow and transport issues relevant to the SZ (e.g., fracture flow in volcanic units, anisotropy, radionuclide transport on colloids, etc.) to be considered in the TSPA model for the LA. For included FEPs, this analysis summarizes the implementation of the FEP in TSPA-LA (i.e., how the FEP is included). For excluded FEPs, this analysis provides the technical basis for exclusion from TSPA-LA (i.e., why the FEP is excluded).

  6. Optimization of protein electroextraction from microalgae by a flow process.

    Science.gov (United States)

    Coustets, Mathilde; Joubert-Durigneux, Vanessa; Hérault, Josiane; Schoefs, Benoît; Blanckaert, Vincent; Garnier, Jean-Pierre; Teissié, Justin

    2015-06-01

    Classical methods, used for large scale treatments such as mechanical or chemical extractions, affect the integrity of extracted cytosolic protein by releasing proteases contained in vacuoles. Our previous experiments on flow processes electroextraction on yeasts proved that pulsed electric field technology allows preserving the integrity of released cytosolic proteins, by not affecting vacuole membranes. Furthermore, large cell culture volumes are easily treated by the flow technology. Based on this previous knowledge, we developed a new protocol in order to electro-extract total cytoplasmic proteins from microalgae (Nannochloropsis salina, Chlorella vulgaris and Haematococcus pluvialis). Given that induction of electropermeabilization is under the control of target cell size, as the mean diameter for N. salina is only 2.5 ?m, we used repetitive 2 ms long pulses of alternating polarities with stronger field strengths than previously described for yeasts. The electric treatment was followed by a 24h incubation period in a salty buffer. The amount of total protein release was observed by a classical Bradford assay. A more accurate evaluation of protein release was obtained by SDS-PAGE. Similar results were obtained with C. vulgaris and H. pluvialis under milder electrical conditions as expected from their larger size. PMID:25216607

  7. Using hydraulic equivalences to discriminate transport processes of volcanic flows

    Science.gov (United States)

    Burgisser, Alain; Gardner, James E.

    2006-03-01

    We characterized stratified deposits from the Upper Toluca Pumice at Toluca volcano, Mexico, to distinguish the various modes of transport at play in their genesis. Using the concept of hydraulic equivalence, we determined that deposits resulted from a combination of suspended-load fallout, saltation, and rolling. In particular, some well-sorted coarse stratified beds have a single pumice mode most likely indicative of clasts having traveled through both the transport system and the traction bed. Such beds are likely remnants of the sorting operated within the large-scale transport system. Other coarse beds have pumice and lithic modes suggesting rolling in the traction bed. We propose that boundary layer processes control the sorting of those beds and all finer beds. By helping to discriminate between transport mechanisms, hydraulic equivalences have a general applicability in geophysical flows involving clasts of contrasted densities.

  8. The question of the digital processing in the coherent pulse doppler radar which radiates the pulse complicated probing signal with a button type ambiguity diagram

    Directory of Open Access Journals (Sweden)

    O. D. Mrachkovskiy

    2013-04-01

    Full Text Available Introduction. The advantages of the pulse complicated signals using in the radar are well-known. These signals are signals with the high time security, the high power security or (and the high structural security. The signal with the symmetrical linear frequency modulation, the signal with the triangular frequency modulation, the signal with the trapezoidal frequency modulation, the signal with the quadratic and with the cubic frequency intra -modulation and the signal with pseudorandom sequence have the button ambiguity function. Problem statement. It is necessary: To conduct the comparative estimation of the distance resolution and the range rate resolution (Doppler resolution for signals with the button type ambiguity diagram; To develop recommendations for determination of the Doppler channels number; Purpose of the article. To estimate the complication of the multichannel locations high-ways realization of echo signal as the multichannel Doppler-beat frequency highway on the base of matched filters or correlators. The analysis of complicated signals potential characteristics. Potential characteristics of the distance resolution and the range rate resolution for the signal with the symmetrical linear frequency modulation, the signal with the triangular frequency modulation, the signal with the trapezoidal frequency modulation, the signal with the quadratic and with the cubic frequency intra-modulation and the signal with pseudorandom sequence are analyzed. Conclusions to advantages of these pulse complicated signals with the button ambiguity function are drawn. Recommendations for determination of the Doppler channels number are developed. The complication of the multichannel locations highways realization of echo signal as the multichannel Doppler-beat frequency highway on the base of matched filters or correlators is estimated. The block diagrams analysis result testifies that the realization of the multichannel Doppler-beat frequency correlator is technically more difficult. In this scheme there is the difficult block with the formation of a probing signal with parallel releases of the so-called Doppler copies. Conclusions. The number of the Doppler channels in the radar locations highway deter-mined by maximum target velocity by the falling possible level of the noise immunity and of the distance resolution and the range rate resolution of probing signal that is used. The use of the considered complicated signals any types provides the identical number of processing channels. The use of the signal with pseudorandom sequence supports the high time security, the high power security and the high structural security.

  9. Eigenanalysis of a neural network for optic flow processing

    Science.gov (United States)

    Weber, F.; Eichner, H.; Cuntz, H.; Borst, A.

    2008-01-01

    Flies gain information about self-motion during free flight by processing images of the environment moving across their retina. The visual course control center in the brain of the blowfly contains, among others, a population of ten neurons, the so-called vertical system (VS) cells that are mainly sensitive to downward motion. VS cells are assumed to encode information about rotational optic flow induced by self-motion (Krapp and Hengstenberg 1996 Nature 384 463 6). Recent evidence supports a connectivity scheme between the VS cells where neurons with neighboring receptive fields are connected to each other by electrical synapses at the axonal terminals, whereas the boundary neurons in the network are reciprocally coupled via inhibitory synapses (Haag and Borst 2004 Nat. Neurosci. 7 628 34 Farrow et al 2005 J. Neurosci. 25 3985 93 Cuntz et al 2007 Proc. Natl Acad. Sci. USA). Here, we investigate the functional properties of the VS network and its connectivity scheme by reducing a biophysically realistic network to a simplified model, where each cell is represented by a dendritic and axonal compartment only. Eigenanalysis of this model reveals that the whole population of VS cells projects the synaptic input provided from local motion detectors on to its behaviorally relevant components. The two major eigenvectors consist of a horizontal and a slanted line representing the distribution of vertical motion components across the fly's azimuth. They are, thus, ideally suited for reliably encoding translational and rotational whole-field optic flow induced by respective flight maneuvers. The dimensionality reduction compensates for the contrast and texture dependence of the local motion detectors of the correlation-type, which becomes particularly pronounced when confronted with natural images and their highly inhomogeneous contrast distribution.

  10. Eigenanalysis of a neural network for optic flow processing

    Energy Technology Data Exchange (ETDEWEB)

    Weber, F; Eichner, H; Borst, A [Department of Systems and Computational Neuroscience, Max-Planck-Institute of Neurobiology, Martinsried (Germany); Cuntz, H [Wolfson Institute for Biomedical Research, Department of Physiology, University College London (United Kingdom)], E-mail: weberf@neuro.mpg.de

    2008-01-15

    Flies gain information about self-motion during free flight by processing images of the environment moving across their retina. The visual course control center in the brain of the blowfly contains, among others, a population of ten neurons, the so-called vertical system (VS) cells that are mainly sensitive to downward motion. VS cells are assumed to encode information about rotational optic flow induced by self-motion (Krapp and Hengstenberg 1996 Nature 384 463-6). Recent evidence supports a connectivity scheme between the VS cells where neurons with neighboring receptive fields are connected to each other by electrical synapses at the axonal terminals, whereas the boundary neurons in the network are reciprocally coupled via inhibitory synapses (Haag and Borst 2004 Nat. Neurosci. 7 628-34; Farrow et al 2005 J. Neurosci. 25 3985-93; Cuntz et al 2007 Proc. Natl Acad. Sci. USA). Here, we investigate the functional properties of the VS network and its connectivity scheme by reducing a biophysically realistic network to a simplified model, where each cell is represented by a dendritic and axonal compartment only. Eigenanalysis of this model reveals that the whole population of VS cells projects the synaptic input provided from local motion detectors on to its behaviorally relevant components. The two major eigenvectors consist of a horizontal and a slanted line representing the distribution of vertical motion components across the fly's azimuth. They are, thus, ideally suited for reliably encoding translational and rotational whole-field optic flow induced by respective flight maneuvers. The dimensionality reduction compensates for the contrast and texture dependence of the local motion detectors of the correlation-type, which becomes particularly pronounced when confronted with natural images and their highly inhomogeneous contrast distribution.

  11. Eigenanalysis of a neural network for optic flow processing

    International Nuclear Information System (INIS)

    Flies gain information about self-motion during free flight by processing images of the environment moving across their retina. The visual course control center in the brain of the blowfly contains, among others, a population of ten neurons, the so-called vertical system (VS) cells that are mainly sensitive to downward motion. VS cells are assumed to encode information about rotational optic flow induced by self-motion (Krapp and Hengstenberg 1996 Nature 384 463-6). Recent evidence supports a connectivity scheme between the VS cells where neurons with neighboring receptive fields are connected to each other by electrical synapses at the axonal terminals, whereas the boundary neurons in the network are reciprocally coupled via inhibitory synapses (Haag and Borst 2004 Nat. Neurosci. 7 628-34; Farrow et al 2005 J. Neurosci. 25 3985-93; Cuntz et al 2007 Proc. Natl Acad. Sci. USA). Here, we investigate the functional properties of the VS network and its connectivity scheme by reducing a biophysically realistic network to a simplified model, where each cell is represented by a dendritic and axonal compartment only. Eigenanalysis of this model reveals that the whole population of VS cells projects the synaptic input provided from local motion detectors on to its behaviorally relevant components. The two major eigenvectors consist of a horizontal and a slanted line representing the distribution of vertical motion components across the fly's azimuth. They are, thus, ideally su fly's azimuth. They are, thus, ideally suited for reliably encoding translational and rotational whole-field optic flow induced by respective flight maneuvers. The dimensionality reduction compensates for the contrast and texture dependence of the local motion detectors of the correlation-type, which becomes particularly pronounced when confronted with natural images and their highly inhomogeneous contrast distribution

  12. Self Cleaning HEPA Filtration without Interrupting Process Flow

    International Nuclear Information System (INIS)

    The strategy of protecting the traditional glass fibre HEPA filtration train from it's blinding contamination and the recovery of dust by the means of self cleaning, pre-filtration is a proven means in the reduction of ultimate disposal volumes and has been used within the Fuel Production Industry. However, there is an increasing demand in nuclear applications requiring elevated operating temperatures, fire resistance, moisture resistance and chemical composition that the existing glass fibre HEPA filtration cannot accommodate, which can be remedied by the use of a metallic HEPA filter media. Previous research (Bergman et al 1997, Moore et al 1992) suggests that the then costs to the DOE, based on a five year life cycle, was $29.5 million for the installation, testing, removal and disposal of glass fibre HEPA filtration trains. Within these costs, $300 was the value given to the filter and $4,450 was given to the peripheral activity. Development of a low cost, cleanable, metallic, direct replacement of the traditional filter train will the clear solution. The Bergman et al work has suggested that a 1000 ft3/min, cleanable, stainless HEPA could be commercially available for $5,000 each, whereas the industry has determined that the truer cost of such an item in isolation would be closer to $15,000. This results in a conflict within the requirement between 'low cost' and 'stainless HEPA'. By proposing a system that combines metallic HEPA filtration with the abbines metallic HEPA filtration with the ability to self clean without interrupting the process flow, the need for a tradition HEPA filtration train will be eliminated and this dramatically reduces the resources required for cleaning or disposal, thus presenting a route to reducing ultimate costs. The paper will examine the performance characteristics, filtration efficiency, flow verses differential pressure and cleanability of a self cleaning HEPA grade sintered metal filter element, together with data to prove the contention. (authors)

  13. Integrability and MHV diagrams

    CERN Document Server

    Brandhuber, Andreas; Travaglini, Gabriele; Young, Donovan

    2014-01-01

    We apply MHV diagrams to the derivation of the one-loop dilatation operator of N=4 super Yang-Mills in the SO(6) sector. We find that in this approach the calculation reduces to the evaluation of a single MHV diagram in dimensional regularisation. This provides the first application of MHV diagrams to an off-shell quantity. We also discuss other applications of the method and future directions.

  14. Pseudohaptic interaction with knot diagrams

    Science.gov (United States)

    Weng, Jianguang; Zhang, Hui

    2012-07-01

    To make progress in understanding knot theory, we need to interact with the projected representations of mathematical knots, which are continuous in three dimensions (3-D) but significantly interrupted in the projective images. One way to achieve such a goal is to design an interactive system that allows us to sketch two-dimensional (2-D) knot diagrams by taking advantage of a collision-sensing controller and explore their underlying smooth structures through a continuous motion. Recent advances of interaction techniques have been made that allow progress in this direction. Pseudohaptics that simulate haptic effects using pure visual feedback can be used to develop such an interactive system. We outline one such pseudohaptic knot diagram interface. Our interface derives from the familiar pencil-and-paper process of drawing 2-D knot diagrams and provides haptic-like sensations to facilitate the creation and exploration of knot diagrams. A centerpiece of the interaction model simulates a physically reactive mouse cursor, which is exploited to resolve the apparent conflict between the continuous structure of the actual smooth knot and the visual discontinuities in the knot diagram representation. Another value in exploiting pseudohaptics is that an acceleration (or deceleration) of the mouse cursor (or surface locator) can be used to indicate the slope of the curve (or surface) of which the projective image is being explored. By exploiting these additional visual cues, we proceed to a full-featured extension to a pseudohaptic four-dimensional (4-D) visualization system that simulates the continuous navigation on 4-D objects and allows us to sense the bumps and holes in the fourth dimension. Preliminary tests of the software show that main features of the interface overcome some expected perceptual limitations in our interaction with 2-D knot diagrams of 3-D knots and 3-D projective images of 4-D mathematical objects.

  15. Mixing processes - Influence of the viscosity model on flow calculations

    Science.gov (United States)

    Erb, T.; Geiger, K.; Bonten, C.

    2014-05-01

    Distributive mixing plays an important role in polymer processing, especially for shear-sensitive materials. Many materials with very high filler contents or partly crosslinked materials show a rheological yield point, which makes mixing of such materials very difficult. Due to this fact it is very important to predict the mixing behavior before expensive mixing devices are manufactured or production stops due to insufficient product quality. Besides the mixing quality, both pressure drop and dissipative heating are important quality criteria for mixer geometries. The CARPOW equation presented in this paper is capable to describe the flow behavior of materials with a rheological yield point depending on the shear rate and temperature due to a combination of a Carreau equation and a power law. The implementation of this fluid model in the open source CFD toolbox Open-FOAM® and the combination with a particle tracking approach allow predicting the mixing behavior of such materials in distributive mixing devices. Numerical calculations were done with two mixer geometries and two material systems in order to investigate the influence of the selected viscosity model on the calculation results.

  16. A Feynman diagram analyzer DIANA: recent development

    OpenAIRE

    Tentyukov, M.; Fleischer, J.

    2002-01-01

    New developments concerning the extension of the Feynman diagram analyzer DIANA are presented. We discuss new graphic facilities, application of DIANA to processes with Majorana fermions and different approaches to automation of momenta distribution.

  17. Lenses and Ray Diagrams

    Science.gov (United States)

    Michael Horton

    2009-05-30

    This is the first time that students will draw technical ray diagrams (in previous experiments, they simply sketched the rays). They need a little instruction in drawing ray diagrams before they can do it, so the activity is not purely inquiry. But it is

  18. Logical reasoning with diagrams

    CERN Document Server

    Allwein, Gerard

    1996-01-01

    PART A: Theoretical Issues. 1. Visual Information and Valid Reasoning, Jon Barwise and John Etchemendy. 2. Operational Constraints in Diagrammatic Reasoning, Atsushi Shimojima. 3. Diagrams and the Concept of Logical System, Jon Barwise and Eric Hammer. PART B: Case Studies. 4. Situation-Theoretic Account of Valid Reasoning with Venn Diagrams, Sun-Joo Shin. 5. Towards a Model Theory of Venn Diagrams, eric Hammer and Norman Danner. 6. Peircean Graphs for Propositional Logic, Eric Hammer. 7. A Diagrammatic Subsystem of Hilbert''s Geometry, Isabel Luengo. PART C: Heterogenous Systems. 8. Heterogenous Logic, Jon Barwise and John Etchemendy. 9. Toward the Rigorous Use of Diagrams in Reasoning about Hardware, Steven D. Johnson, Jon Barwise, and Gerard Allwein. 10. Exploiting the Potential of Diagrams in Guiding Hardware Reasoning, Kathi D. Fisler

  19. Neuro-flow Dynamics and the Learning Processes

    CERN Document Server

    Tatsuno, M

    1997-01-01

    A new description of the neural activity is introduced by the neuro-flow dynamics and the extended Hebb rule. The remarkable characteristics of the neuro-flow dynamics, such as the primacy and the recency effect during awakeness or sleep, are pointed out.

  20. INDUSTRIAL PROCESS PROFILES FOR ENVIRONMENTAL USE: CHAPTER 26. TITANIUM INDUSTRY

    Science.gov (United States)

    The titanium industry produces two principal products, titanium metal and titanium dioxide. For purposes of analyses, therefore, the industry is considered in two segments: titanium metal production and titanium dioxide production. Two industrial process flow diagrams and eleven ...

  1. Quantum Diagrams and Quantum Networks

    OpenAIRE

    Kauffman, Louis H.; Lomonaco Jr, Samuel J.

    2014-01-01

    This paper is an introduction to diagrammatic methods for representing quantum processes and quantum computing. We review basic notions for quantum information and quantum computing. We discuss topological diagrams and some issues about using category theory in representing quantum computing and teleportation. We analyze very carefully the diagrammatic meaning of the usual representation of the Mach-Zehnder interferometer, and we show how it can be generalized to associate t...

  2. On the application of kinematic models to simulate the diffusive processes of debris flows

    OpenAIRE

    Arattano, M.; Franzi, L.

    2010-01-01

    Debris flows generally propagate along steep mountain torrents with dynamics primarily governed by gravitational and frictional forces. Thus, debris flows modelling can be successfully performed through the application of kinematic models, which consider only the effects of slope and friction and neglect the remaining terms of the momentum equation. However, the diffusion processes that can be observed in the field, such as the spreading of the debris flow wave as it flows downstream, can not...

  3. Effect of relaxation processes on initial stages of flow in iron

    International Nuclear Information System (INIS)

    Investigated are behaviour and structure of commercially pure iron in the range of microplastic deformation below the flow limit, using the methods of mechanical tests of amplitude dependence of internal friction and transmission electron microscopy. Conclusion is made about an appearance of delayed flow process not only in case of changes in loading rate, but under static tests as well, permitting to induce material flow when holding under stresses below the flow limit

  4. Evolution of Plastic Strain During a Flow Forming Process

    CERN Document Server

    Roy, M J; Wood, J T; 10.1016/j.jmatprotec.2008.03.030

    2011-01-01

    The distribution of equivalent plastic strain through the thickness of several AISI 1020 steel plates formed under different conditions over a smooth cylindrical mandrel using a single-roller forward flow forming operation was studied by measuring the local micro-indentation hardness of the deformed material. The equivalent plastic strain was higher at the inner and outer surfaces and lowest at the center of the workpiece. Empirical expressions are presented which describe the contribution of the roller and mandrel to the total local equivalent plastic strain within the flow formed part. The dependence of these expressions upon the thickness reduction during flow forming is discussed.

  5. Sn60Pb40 solder powders produced by the planar flow casting atomization process

    OpenAIRE

    Xiang Qingchun; Zhao Jing; Pan Haicheng

    2011-01-01

    Conventional planar flow casting (PFC) is one of rapid solidification processes for the fabrication of microcrystalline or amorphous ribbons. Based on the conventional PFC process, the planar flow casting atomization (PFCA) process has been developed, which is a new rapid solidification process for the production of metal powder directly from alloy melts. A prototype experimental apparatus was designed and manufactured. With the apparatus, Sn60Pb40 alloy solder powders were prepared, and the ...

  6. Binary phase diagrams

    International Nuclear Information System (INIS)

    The paper reviews ten binary phase diagrams of pairs of alkali metals. The systems considered include: Cs-K, Cs-Li, Cs-Na, Cs-Rb, K-Li, K-Na, K-Rb, Li-Na, Li-Rb and Na-Rb. Phase diagrams are presented for all systems, apart from the K-Li, Cs-Li and Li-Rb systems. The latter two systems appear little studied, although solubility studies have been carried out for the K-Li system. In addition to a phase diagram for system K-Na, the effects of pressure have also been investigated. (U.K.)

  7. Novel ''flow injection'' channel flow cell for the investigation of processes at solid-liquid interfaces .1. Theory

    OpenAIRE

    Gooding, Jj; Coles, Ba; Compton, Rg

    1997-01-01

    A novel "flow injection" channel flow cell is described which enables transient phenomena at the solid-liquid interface to be investigated. In the cell the solution reactant is injected into the main channel of a flow cell upstream from, and through the opposite wall from, the solid substrate. A detector electrode is positioned downstream of the latter so that current-time transients can be used to infer the kinetics and mechanism of processes at the solid-liquid interface. The performance of...

  8. Genealogy of flows of continuous-state branching processes via flows of partitions and the Eve property

    CERN Document Server

    Labbé, Cyril

    2012-01-01

    We encode the genealogy of a continuous-state branching process associated with a branching mechanism $\\Psi$ - or $\\Psi$-CSBP in short - using a stochastic flow of partitions. This encoding holds for all branching mechanisms and appears as a very tractable object to deal with asymptotic behaviours and convergences. In particular we study the so-called Eve property - the existence of an ancestor from which the entire population descends asymptotically - and give a necessary and sufficient condition on the $\\Psi$-CSBP for this property to hold. Finally, we show that the flow of partitions unifies the lookdown representation and the flow of subordinators when the Eve property holds.

  9. Stochastic Modelling of Shiroro River Stream flow Process

    Directory of Open Access Journals (Sweden)

    Musa, J. J

    2013-01-01

    Full Text Available Economists, social scientists and engineers provide insights into the drivers of anthropogenic climate change and the options for adaptation and mitigation, and yet other scientists, including geographers and biologists, study the impacts of climate change. This project concentrates mainly on the discharge from the Shiroro River. A stochastic approach is presented for modeling a time series by an Autoregressive Moving Average model (ARMA. The development and use of a stochastic stream flow model involves some basic steps such as obtain stream flow record and other information, Selecting models that best describes the marginal probability distribution of flows. The flow discharge of about 22 years (1990-2011 was gotten from the Meteorological Station at Shiroro and analyzed with three different models namely; Autoregressive (AR model, Autoregressive Moving Average (ARMA model and Autoregressive Integrated Moving Average (ARIMA model. The initial model identification is done by using the autocorrelation function (ACF and partial autocorrelation function (PACF. Based on the model analysis and evaluations, proper predictions for the effective usage of the flow from the river for farming activities and generation of power for both industrial and domestic us were made. It also highlights some recommendations to be made to utilize the possible potentials of the river effectively

  10. Satellite Venn Diagram

    Science.gov (United States)

    In this activity, students will use the background information they have read to organize a list of sources and objects, putting each item given in the appropriate part of the Venn diagram, depending on which instrument will study that item. Students will demonstrate their understanding of spectra, astronomical observations, and have read the background material on Chandra, Astro-E and the microcalorimeter, and the Constellation X-ray Observatory. They will write a five minute summary of the capabilities of the three observatories, based on their Venn diagram. Students' understanding of the background material will be evaluated based on the accuracy of their Venn diagrams and the interpretation of the information on the Venn diagrams from their closure paper.

  11. Influence of Processing Parameters on the Flow Path in Friction Stir Welding

    Science.gov (United States)

    Schneider, J. A.; Nunes, A. C., Jr.

    2006-01-01

    Friction stir welding (FSW) is a solid phase welding process that unites thermal and mechanical aspects to produce a high quality joint. The process variables are rpm, translational weld speed, and downward plunge force. The strain-temperature history of a metal element at each point on the cross-section of the weld is determined by the individual flow path taken by the particular filament of metal flowing around the tool as influenced by the process variables. The resulting properties of the weld are determined by the strain-temperature history. Thus to control FSW properties, improved understanding of the processing parameters on the metal flow path is necessary.

  12. Modal Object Diagrams

    OpenAIRE

    Maoz, Shahar; Ringert, Jan Oliver; Rumpe, Bernhard

    2014-01-01

    While object diagrams (ODs) are widely used as a means to document object-oriented systems, they are expressively weak, as they are limited to describe specific possible snapshots of the system at hand. In this paper we introduce modal object diagrams (MODs), which extend the classical OD language with positive/negative and example/invariant modalities. The extended language allows the designer to specify not only positive example models but also negative examples, ones that...

  13. Traffic engineering eye diagram

    OpenAIRE

    Kowalik, Karol; Collier, Martin

    2005-01-01

    It is said that a picture is worth a thousand words - this statement also applies to networking topics. Thus, to effectively monitor network performance we need tools which present the performance metrics in a graphical way which is also clear and informative. We propose a tool for this purpose which we call the traffic engineering eye diagram (TEED). Eye diagrams are used in digital communications to analyse the quality of a digital signal; the TEED can similarly he used in the traffic engin...

  14. Flow regulation of variable feed pressure stream: process and device

    International Nuclear Information System (INIS)

    The stream is separated into a main stream and a coaxial control stream. The control stream is formed into a vortex in which the rotational axis is parallel to the flow direction of the main stream. The control stream vortex is directed towards the main stream to ensure the regulation of the fluid flow by direct interaction of the two streams. The device comprises a central tube with perforated plates around it. A structure, through which thin and straight pipes pass, and a cylindrical envelope including outlet pipes inclined with regard to the radial direction of the envelope are set in the central tube. The invention applies, more particularly, to the regulation of the liquid sodium flow rate in the used assemblies of a fast neutron nuclear reactor, during their cooling storage in the reactor vessel

  15. Design of image processing embedded systems using multidimensional data flow

    CERN Document Server

    Keinert, Joachim

    2010-01-01

    This book presents a new set of embedded system design techniques called multidimensional data flow, which combine the various benefits offered by existing methodologies such as block-based system design, high-level simulation, system analysis and polyhedral optimization. It describes a novel architecture for efficient and flexible high-speed communication in hardware that can be used both in manual and automatic system design and that offers various design alternatives, balancing achievable throughput with required hardware size. This book demonstrates multidimensional data flow by showing it

  16. Measurement system of bubbly flow using Ultrasonic Velocity Profile Monitor and Video Data Processing Unit. 3. Comparison of flow characteristics between bubbly cocurrent and countercurrent flows

    International Nuclear Information System (INIS)

    The authors have developed a new measurement system which consisted of an Ultrasonic Velocity Profile Monitor (UVP) and a Video Data Processing Unit (VDP) in order to clarify the two-dimensional flow characteristics in bubbly flows and to offer a data base to validate numerical codes for two-dimensional two-phase flow. In the present paper, the proposed measurement system is applied to fully developed bubbly cocurrent flows in a vertical rectangular channel. At first, both bubble and water velocity profiles and void fraction profiles in the channel were investigated statistically. In addition, the two-phase multiplier profile of turbulence intensity, which was defined as a ratio of the standard deviation of velocity fluctuation in a bubbly flow to that in a water single phase flow, were examined. Next, these flow characteristics were compared with those in bubbly countercurrent flows reported in our previous paper. Finally, concerning the drift flux model, the distribution parameter and drift velocity were obtained directly from both bubble and water velocity profiles and void fraction profiles, and their results were compared with those in bubbly countercurrent flows. (author)

  17. Measurement system of bubbly flow using ultrasonic velocity profile monitor and video data processing unit. 2. Flow characteristics of bubbly countercurrent flow

    International Nuclear Information System (INIS)

    The authors have developed a measurement system which is composed of an ultrasonic velocity profile monitor and a video data processing unit in order to clarify its multi-dimensional flow characteristics in bubbly flows and to offer a data base to validate numerical codes for multi-dimensional two-phase flow. In this paper, the measurement system was applied for bubbly countercurrent flows in a vertical rectangular channel. At first, both bubble and water velocity profiles and void fraction profiles in the channel were investigated statistically. Next, turbulence intensity in a continuous liquid phase was defined as a standard deviation of velocity fluctuation, and the two-phase multiplier profile of turbulence intensity in the channel was clarified as a ratio of the standard deviation of flow fluctuation in a bubbly countercurrent flow to that in a water single phase flow. Finally, the distribution parameter and drift velocity used in the drift flux model for bubbly countercurrent flows were calculated from the obtained velocity profiles of both phases and void fraction profile, and were compared with the correlation proposed for bubbly countercurrent flows. (author)

  18. Dynamic Modelling of Erosion and Deposition Processes in Debris Flows With Application to Real Debris Flow Events in Switzerland

    Science.gov (United States)

    Deubelbeiss, Y.; McArdell, B. W.; Graf, C.

    2011-12-01

    The dynamics of a debris flow can be significantly influenced by erosion and deposition processes during an event because volume changes have a strong influence on flow properties such as flow velocity, flow heights and runout distances. It is therefore worth exploring how to include these processes in numerical models, which are used for hazard assessment and mitigation measure planning. However, it is still under debate, what mechanism drives the erosion of material at the base of a debris flow. There are different processes attributed to erosion: it has been proposed that erosion correlates with the stresses due to granular interactions at the front, which in turn strongly depend on particle size or it may be related to basal shear forces. Because it is expected that larger flow heights result in larger stresses one can additionally hypothesize that there is a correlation between erosion rate and flow height. To test different erosion laws in a numerical model and its influence on the flow behavior we implement different relationships and compare simulation results with field data. Herefore, we use the numerical model, RAMMS (Christen et al., 2010), employing the Voellmy-fluid friction law. While it has already been shown that a correlation of erosion with velocity does not lead to a satisfying result (too high entrainment in the tail) a correlation with flow height combined with velocity (momentum) has been successfully applied to ice-avalanches. Currently, we are testing the momentum-driven and for comparison we reconsider the simple velocity-driven erosion rate. However, these laws do not consider processes on a smaller scale such as particle fluctuations resulting in energy production, which might play an important role. Therefore, we additionally consider an erosion model that has potential to draw new insights on the erosion process in debris flows. The model is based on an extended Voellmy model, which additionally employs an equation, which is a measure of the random kinetic energy (RKE, equivalent to granular temperature) produced by the random movement of particles in a debris flow (Buser and Bartelt, 2009). Advantageous is that friction is dependent on the production of RKE and is decreasing with decreasing RKE. The amount of energy produced in the system, might therefore be a useful indicator for the erosion rate. While the erosion model using the Voellmy approach might be successfully applicable to cases where erosion and bulking are the main processes, such as in Illgraben (CH), it might be less straight forward in mountain torrents where we additionally observe a lot of deposition along the flow path such as in Dorfbach (CH). The extended Voellmy model is indirectly accounting for this process as friction is a function of RKE, which allows material to deposit earlier. At both locations we have debris flow observation stations including innovative new measurement techniques indication parameters such as flow velocity, height and volumes at specific locations (Illgraben, Dorfbach) as well as erosion rate measurements (Illgraben). These highly valuable data allow us good model calibration as well as verification of the newly implemented erosion models.

  19. Modeling field scale unsaturated flow and transport processes

    International Nuclear Information System (INIS)

    The scales of concern in subsurface transport of contaminants from low-level radioactive waste disposal facilities are in the range of 1 to 1,000 m. Natural geologic materials generally show very substantial spatial variability in hydraulic properties over this range of scales. Such heterogeneity can significantly influence the migration of contaminants. It is also envisioned that complex earth structures will be constructed to isolate the waste and minimize infiltration of water into the facility. The flow of water and gases through such facilities must also be a concern. A stochastic theory describing unsaturated flow and contamination transport in naturally heterogeneous soils has been enhanced by adopting a more realistic characterization of soil variability. The enhanced theory is used to predict field-scale effective properties and variances of tension and moisture content. Applications illustrate the important effects of small-scale heterogeneity on large-scale anisotropy and hysteresis and demonstrate the feasibility of simulating two-dimensional flow systems at time and space scales of interest in radioactive waste disposal investigations. Numerical algorithms for predicting field scale unsaturated flow and contaminant transport have been improved by requiring them to respect fundamental physical principles such as mass conservation. These algorithms are able to provide realistic simulations of systems with very dry initial conditions and high degrees of heterogeneity. Numerical simulation of the movement of water and air in unsaturated soils has demonstrated the importance of air pathways for contaminant transport. The stochastic flow and transport theory has been used to develop a systematic approach to performance assessment and site characterization. Hypothesis-testing techniques have been used to determine whether model predictions are consistent with observed data

  20. Modeling field scale unsaturated flow and transport processes

    Energy Technology Data Exchange (ETDEWEB)

    Gelhar, L.W.; Celia, M.A.; McLaughlin, D. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Civil and Environmental Engineering

    1994-08-01

    The scales of concern in subsurface transport of contaminants from low-level radioactive waste disposal facilities are in the range of 1 to 1,000 m. Natural geologic materials generally show very substantial spatial variability in hydraulic properties over this range of scales. Such heterogeneity can significantly influence the migration of contaminants. It is also envisioned that complex earth structures will be constructed to isolate the waste and minimize infiltration of water into the facility. The flow of water and gases through such facilities must also be a concern. A stochastic theory describing unsaturated flow and contamination transport in naturally heterogeneous soils has been enhanced by adopting a more realistic characterization of soil variability. The enhanced theory is used to predict field-scale effective properties and variances of tension and moisture content. Applications illustrate the important effects of small-scale heterogeneity on large-scale anisotropy and hysteresis and demonstrate the feasibility of simulating two-dimensional flow systems at time and space scales of interest in radioactive waste disposal investigations. Numerical algorithms for predicting field scale unsaturated flow and contaminant transport have been improved by requiring them to respect fundamental physical principles such as mass conservation. These algorithms are able to provide realistic simulations of systems with very dry initial conditions and high degrees of heterogeneity. Numerical simulation of the movement of water and air in unsaturated soils has demonstrated the importance of air pathways for contaminant transport. The stochastic flow and transport theory has been used to develop a systematic approach to performance assessment and site characterization. Hypothesis-testing techniques have been used to determine whether model predictions are consistent with observed data.

  1. Overview of the FAF3 Freight Flow Matrix Construction Process

    Energy Technology Data Exchange (ETDEWEB)

    Sprung, Michael J [ORNL; Southworth, Frank [ORNL; Davidson, Diane [ORNL; Hwang, Ho-Ling [ORNL; Peterson, Bruce E [ORNL; Chin, Shih-Miao [ORNL; Vogt, David P [ORNL; Li, Jan-Mou [ORNL

    2011-01-01

    PROJECT DESCRIPTION The FAF3 is a FHWA freight data product which provides a national O-D matrix of commodity flows to, from, and within the United States. FAF3 freight flows are reported in terms of both annual tons and annual dollars of freight moved by mode of transportation. Based largely on the 2007 CFS, FAF3 utilizes domestic freight flow characteristics, geographic regions, and the SCTG commodity coding system from CFS. However, many freight flows were not captured by the 2007 CFS due to scope and sample size limitations. Approximately 100,000 establishments were sampled out of some 754,000 freight moving establishments in 2007 and imports are out of scope entirely. To estimate missing data values, the approach taken in FAF3 was to use a combination of a novel Log-linear modeling approach (LLM) with an iterative proportional fitting (IPF) routine that also uses additional data inputs to fill in the missing pieces. The complete FAF3 O-D Commodity Mode database is made up of 131 Origins x 131 Destinations x 43 Commodity Classes x 8 Modal categories, for annual tons and dollars. This poster illustrates how the 2007 CFS data were integrated with several additional data sources using LLM and IPF to create a comprehensive FAF3 national freight flow matrix. More detailed documentation on the sources and methods utilized in the development of FAF3 are available from the FHWA website at the following website: http://www.ops.fhwa.dot. gov/freight/freight_analysis/faf/index.htm.

  2. The thermodynamic quantity minimized in steady heat and fluid flow processes: A control volume approach

    International Nuclear Information System (INIS)

    Highlights: ? The optimality in both heat and fluid flow systems has been investigated. ? A new thermodynamic property has been introduced. ? The second law of thermodynamics was extended to present the temheat balance that included the temheat destruction. ? The principle of temheat destruction minimization was introduced. ? It is shown that the rate of total temheat destruction is minimized in steady heat conduction and fluid flow problems. - Abstract: Heat transfer and fluid flow processes exhibit similarities as they occur naturally and are governed by the same type of differential equations. Natural phenomena occur always in an optimum way. In this paper, the natural optimality that exists in the heat transfer and fluid flow processes is investigated. In this regard, heat transfer and fluid flow problems are treated as optimization problems. We discovered a thermodynamic quantity that is optimized during the steady heat transfer and fluid flow processes. Consequently, a new thermodynamic property, the so called temheat, is introduced using the second law of thermodynamics and the definition of entropy. It is shown, through several examples, that overall temheat destruction is always minimized in steady heat and fluid flow processes. The principle of temheat destruction minimization that is based on the temheat balance equation provides a better insight to understand how the natural flow processes take place.

  3. Aerodynamic Structures and Processes in Rotationally Augmented Flow Fields

    DEFF Research Database (Denmark)

    Schreck, Scott J.; SØrensen, Niels

    2007-01-01

    Rotational augmentation of horizontal axis wind turbine blade aerodynamics currently remains incompletely characterized and understood.To address this, the present study concurrently analysed experimental measurements and computational predictions, both of which were unique and of high quality. Experimental measurements consisted of surface pressure data statistics used to infer sectional boundary layer state and to quantify normal force levels.Computed predictions included high-resolution boundary layer topologies and detailed above-surface flow field structures. This synergy was exploited to reliably identify and track pertinent features in the rotating blade boundary layer topology as they evolved in response to varying wind speed.Subsequently,boundary layer state was linked to abovesurface flow field structure and used to deduce mechanisms underlying augmented aerodynamic force production during rotating conditions.

  4. Simulations of ductile flow in brittle material processing

    Energy Technology Data Exchange (ETDEWEB)

    Luh, M.H.; Strenkowski, J.S.

    1988-12-01

    Research is continuing on the effects of thermal properties of the cutting tool and workpiece on the overall temperature distribution. Using an Eulerian finite element model, diamond and steel tools cutting aluminum have been simulated at various, speeds, and depths of cut. The relative magnitude of the thermal conductivity of the tool and the workpiece is believed to be a primary factor in the resulting temperature distribution in the workpiece. This effect is demonstrated in the change of maximum surface temperatures for diamond on aluminum vs. steel on aluminum. As a preliminary step toward the study of ductile flow in brittle materials, the relative thermal conductivities of diamond on polycarbonate is simulated. In this case, the maximum temperature shifts from the rake face of the tool to the surface of the machined workpiece, thus promoting ductile flow in the workpiece surface.

  5. Stochastic Modelling of Shiroro River Stream flow Process

    OpenAIRE

    Musa, J. J.

    2013-01-01

    Economists, social scientists and engineers provide insights into the drivers of anthropogenic climate change and the options for adaptation and mitigation, and yet other scientists, including geographers and biologists, study the impacts of climate change. This project concentrates mainly on the discharge from the Shiroro River. A stochastic approach is presented for modeling a time series by an Autoregressive Moving Average model (ARMA). The development and use of a stochastic stream flow m...

  6. Gaussian process emulators for uncertainty analysis in groundwater flow

    OpenAIRE

    Stone, Nicola

    2011-01-01

    In the field of underground radioactive waste disposal, complex computer models are used to describe the flow of groundwater through rocks. An important property in this context is transmissivity, the ability of the groundwater to pass through rocks, and the transmissivity field can be represented by a stochastic model. The stochastic model is included in complex computer models which determine the travel time for radionuclides released at one point to reach another. As well as the uncerta...

  7. Digital video image processing applications to two phase flow measurements

    International Nuclear Information System (INIS)

    Liquid spraying is common in various fields (combustion, cooling of hot surfaces, spray drying,...). For two phase flows modeling, it is necessary to test elementary laws (vaporizing drops, equation of motion of drops or bubbles, heat transfer..). For example, the knowledge of the laws related to the behavior of vaporizing liquid drop in a hot airstream and impinging drops on a hot surface is important for two phase flow modeling. In order to test these different laws in elementary cases, the authors developed different measurement techniques, associating video and microcomputers. The test section (built in perpex or glass) is illuminated with a thin sheet of light generated by a 15mW He-Ne laser and appropriate optical arrangement. Drops, bubbles or liquid film are observed at right angle by a video camera synchronised with a microcomputer either directly or with an optical device (lens, telescope, microscope) providing sufficient magnification. Digitizing the video picture in real time associated with an appropriate numerical treatment allows to obtain, in a non interfering way, a lot of informations relative to the pulverisation and the vaporization as function of space and time (drop size distribution; Sauter mean diameter as function of main flow parameters: air velocity, surface tension, temperature; isoconcentration curves, size evolution relative to vaporizing drops, film thickness evolution spreading on a hot surface...)..)

  8. Modeling of Gas Flows in Steelmaking Decarburization Processes

    OpenAIRE

    Song, Zhili Jack

    2013-01-01

    The purpose of the current study is to increase the understanding of different steelmaking processes at the decarburization stages by use of mathematical modeling. More specifically, two De-Laval nozzles from a VOD (Vaccum Oxygen Decarburization) process, which is used for producing stainless steels with ultra-low carbon grades, was investigated for different vessel pressures. Moreover, the post combustion phenomena in a BOF or LD (Linz-Donawitz) process as well as an AOD (Argon Oxygen Decarb...

  9. Parameterization of near-bed processes under collinear wave and current flows from a two-phase sheet flow model

    OpenAIRE

    Amoudry, Laurent O.; Liu, Philip L. -f

    2010-01-01

    Sediment transport models require appropriate representation of near-bed processes. We aim here to explore the parameterizations of bed shear stress, bed load transport rate and near-bed sediment erosion rate under the sheet flow regime. To that end, we employ a one-dimensional two-phase sheet flow model which is able to resolve the intrawave boundary layer and sediment dynamics at a length scale on the order of the sediment grain. We have conducted 79 numerical simulations to cover a range o...

  10. Sensitivity analysis of reacting two-phase flow in nuclear heat-based gasification process

    Directory of Open Access Journals (Sweden)

    Jakub Marcin Kupecki

    2011-01-01

    Full Text Available Current work investigates influence of operating parameters on chemical reactions occuring within two-phase reacting flow. This particular flow analysed, corresponds to processes in coal gasifier unit supplied in heat by a high temperature gas cooled nuclear reactor (HTGR.Due to the fact that gasification is a complex process, in which multiphase mixture undergoes chemical reactions, it crucial to answer questions about sensitivity to parameters changes. Performed analysis was dedicated to answer question about the optimal flow parameters. Controll of flow patern, namely the swirl of coal-oxygen mixture traversing the gasifier domain, allowed creating efficiency curve, relating gas composition with non-axial component of the velocity vector.Using numerical model of the process, numbers of simulations were run in order to determine operation point yielding the highest efficiency, defined as a ratio of lower heating values of a syngas product of gasification process and coal feed into the unit.

  11. Diblock copolymer phase diagram

    Science.gov (United States)

    Iacovella, Christopher R.

    2006-11-20

    Adaptation of the Matsen and Bates BCP phase diagram predicted using Mean-field Theory. * Matsen MW, Bates FS, ''http://pubs3.acs.org/acs/journals/doilookup?in_doi=10.1021/ma951138i Unifying weak- and strong-segregation block copolymer theories. Diblock copolymer phase diagram as calculated using Mean-field Theory by Matsen and Bates, where fA is the Block fraction, ? is the Flory-Huggins Chi Parameter, and N is the length of the block.

  12. Views on the calculation of flow and dispersion processes in fractured rock

    International Nuclear Information System (INIS)

    In the report some basic aspects on model types, physical processes, determination of parameters are discussed in relation to a description of flow and dispersion processes in fractured rocks. As far as model types concern it is shown that Darcy's law and the dispersion equation are not especially applicable. These equations can only describe an average situation of flow and spreading while in reality very large deviations could exist between an average situation and the flow and concentration distribution for a certain fracture geometry. The reason for this is primarily the relation between the length scales for the repository and the near field and the fracture system respectively and the poor connectivity between fractures or expressed in another way - the geosphere can not be treated as a continuous medium. The statistical properties of the fractures and the fracture geometry cause large uncertainties in at least two respects: * boundary conditions as to groundwater flow at the repository and thus the mass flow of radioactive material * distribution of flows and concentrations in planes in the geosphere on different distances from the repository. A realistic evaluation of transport and spreading of radioactive material by the groundwater in the geosphere thus requires that the possible variation or uncertainty of the water conducting characteristics of the fracture system is considered. A possible approach is then to describe flow in the geosphere on the basic of the flow in single fractures which are hydraulically connected to each other so that a flow in a fracture system is obtained. The discussion on physical processes which might influence the flow description in single fractures is concentrated to three aspects - factors driving the flow besides the ordinary hydraulic gradient, the viscous properties of water in a very small space (such as a fracture), the influence on the flow of heat release from the repository. (42 figs., 28 refs.)

  13. Weak Charge-Changing Flow in Expanding r-Process Environments

    CERN Document Server

    McLaughlin, G C

    1997-01-01

    We assess the prospects for attaining steady nuclear flow equilibrium in expanding r-process environments where beta decay and/or neutrino capture determine the nuclear charge-changing rates. For very rapid expansions, we find that weak steady flow equilibrium normally cannot be attained. However, even when neutron capture processes freeze out in such nonequilibrium conditions, abundance ratios of nuclear species in the r-process peaks might still mimic those attained in weak steady flow. This result suggests that the r-process yield in a regime of rapid expansion can be calculated reliably only when all neutron capture, photodisintegration, and weak interaction processes are fully coupled in a dynamical calculation. We discuss the implications of these results for models of the r-process sited in rapidly expanding neutrino-heated ejecta.

  14. Effects of elliptic flow and resonance decay process on the Kurtosis of net baryon distributions

    International Nuclear Information System (INIS)

    Kurtosis is regarded as a meaningful and promising observable in searching for the possible critical point predicted by QCD. In this paper, the effects of elliptic flow and resonance decay process on the Kurtosis have been studied with Monte Carlo event generators in Au + Au collisions at ? sNN = 200 GeV. The results show that the Kurtosis is not sensitive to elliptic flow and resonance decay process.(authors)

  15. Comparison of Inflation Processes at the 1859 Mauna Loa Flow, HI, and the McCartys Flow Field, NM

    Science.gov (United States)

    Bleacher, Jacob E.; Garry, W. Brent; Zimbelman, James R.; Crumpler, Larry S.

    2012-01-01

    Basaltic lavas typically form channels or tubes during flow emplacement. However, the importance of sheet flow in the development of basalt ic terrains received recognition over the last 15 years. George Walke r?s research on the 1859 Mauna Loa Flow was published posthumously in 2009. In this paper he discusses the concept of endogenous growth, or inflation, for the distal portion of this otherwise channeldominated lava flow. We used this work as a guide when visiting the 1859 flow to help us better interpret the inflation history of the McCartys flow field in NM. Both well preserved flows display similar clues about the process of inflation. The McCartys lava flow field is among the you ngest (approx.3000 yrs) basaltic lava flows in the continental United States. It was emplaced over slopes of <1 degree, which is similar to the location within the 1859 flow where inflation occurred. Although older than the 1859 flow, the McCartys is located in an arid environ ment and is among the most pristine examples of sheet flow morphologies. At the meter scale the flow surface typically forms smooth, undula ting swales that create a polygonal terrain. The literature for simil ar features includes multiple explanatory hypotheses, original breakouts from adjacent lobes, or inflation related upwarping of crust or sa gging along fractures that enable gas release. It is not clear which of these processes is responsible for polygonal terrains, and it is po ssible that one explanation is not the sole cause of this morphology between all inflated flows. Often, these smooth surfaces within an inflated sheet display lineated surfaces and occasional squeeze-ups alon g swale contacts. We interpret the lineations to preserve original fl ow direction and have begun mapping these orientations to better interpret the emplacement history. At the scale of 10s to 100s of meters t he flow comprises multiple topographic plateaus and depressions. Some depressions display level floors with surfaces as described above, while some are bowl shaped with floors covered in broken lava slabs. Th e boundaries between plateaus and depressions are also typically smoo th, grooved surfaces that have been tilted to angles sometimes approaching vertical. The upper margin of these tilted surfaces displays lar ge cracks, sometimes containing squeeze-ups. The bottom boundary with smooth floored depressions typically shows embayment by younger lavas. It appears that this style of terrain represents the emplacement of an extensive sheet that experiences inflation episodes within prefer red regions where lateral spreading of the sheet is inhibited, thereby forming plateaus. Depressions are often the result of non-inflation and can be clearly identified by lateral squeeze-outs along the pit walls that form when the rising crust exposes the still liquid core of the sheet. Our current efforts are focused on.

  16. The significance of late-stage processes in lava flow emplacement: squeeze-ups in the 2001 Etna flow field

    Science.gov (United States)

    Applegarth, L. J.; Pinkerton, H.; James, M. R.

    2009-04-01

    The general processes associated with the formation and activity of ephemeral boccas in lava flow fields are well documented (e.g. Pinkerton & Sparks 1976; Polacci & Papale 1997). The importance of studying such behaviour is illustrated by observations of the emplacement of a basaltic andesite flow at Parícutin during the 1940s. Following a pause in advance of one month, this 8 km long flow was reactivated by the resumption of supply from the vent, which forced the rapid drainage of stagnant material in the flow front region. The material extruded during drainage was in a highly plastic state (Krauskopf 1948), and its displacement allowed hot fluid lava from the vent to be transported in a tube to the original flow front, from where it covered an area of 350,000 m2 in one night (Luhr & Simkin 1993). Determining when a flow has stopped advancing, and cannot be drained in such a manner, is therefore highly important in hazard assessment and flow modelling, and our ability to do this may be improved through the examination of relatively small-scale secondary extrusions and boccas. The 2001 flank eruption of Mt. Etna, Sicily, resulted in the emplacement of a 7 km long compound `a`? flow field over a period of 23 days. During emplacement, many ephemeral boccas were observed in the flow field, which were active for between two and at least nine days. The longer-lived examples initially fed well-established flows that channelled fresh material from the main vent. With time, as activity waned, the nature of the extruded material changed. The latest stages of development of all boccas involved the very slow extrusion of material that was either draining from higher parts of the flow or being forced out of the flow interior as changing local flow conditions pressurised parts of the flow that had been stagnant for some time. Here we describe this late-stage activity of the ephemeral boccas, which resulted in the formation of ‘squeeze-ups' of lava with a markedly different texture to that of the surrounding `a`? flow surface. The appearance of the squeeze-up material in this flow is similar to that of the plastic lava forcibly drained from the front of the Parícutin flow. The squeeze-up features demonstrate marked morphological variation, which was found to reflect the rheology of the material being extruded, the volume of material being extruded, the extrusion rate and the geometry of the source bocca. We describe the final morphology of squeeze-ups from the 2001 flow field, which ranges from relatively fluid flows to extrusions of high-strength material that accumulated above the source bocca, forming features more akin to tumuli. Although tumulus-like in overall shape and dimensions, the morphology and inferred growth mechanisms for these structures leads to them being dubbed ‘exogenous tumuli', to distinguish them from the more familiar tumuli resulting from inflation processes, which are described elsewhere (e.g. Macdonald 1972; Walker 1991; Duncan et al. 2004). The morphological data are then used together with observations of lava surface textures and squeeze-up locations to build up a picture of flow structure and flow dynamics at the time of squeeze-up formation. The structure of the crust underlying the clinker cover can be elucidated by examining the locations in which squeeze-ups occur, as extrusions exploit zones of crustal weakness. It is found that the flow crust plays an increasingly important role in determining the locus of squeeze-ups as the flow evolves. Squeeze-ups that clearly had a high strength upon extrusion formed as a result of high overpressures in the flow interior. The extrusion of such material may represent the latter stages of activity of a long-lived bocca, or the new development of a bocca in a part of the flow that had been stagnant for some time. Examination of squeeze-up textures may help determine whether the material was transported to the extrusion site in an open or closed system, or if it was stored for a significant length of time before extrusion. Information may also

  17. PRODUCTIVITY IMPROVEMENT IN MOULDING BY CHANGES IN WORK PROCESS FLOW

    Directory of Open Access Journals (Sweden)

    K. Subrahmanyam

    2014-04-01

    Full Text Available Foundry industry suffers from poor quality and productivity due to the large number of process parameters, combined with lower penetration of manufacturing automation and shortage of skilled workers compared to other industries. Productivity is development of an attitude of mind and constant urge to find better, cheaper, easier, quicker and safer means of doing a job, manufacturing a product and providing service. It is the certainty of being able to do better today than yesterday, and continuously. Productivity is purely a concept of real process. It is defined as the relation ship of output to associated inputs. Real process that combines the inputs in order to make output includes practically all the activities of a company. Improving productivity it will help the management to analyze on continuing basis. Improving productivity is nothing but the reduction in wastage of resources like men, machines, material, power, space, time etc. Productivity improvement by means of The Improve existing methods of plant operation, Improve the planning of work and the use of manpower, Increase the effectiveness of all employees. This helps correct identification of the unwanted process. Based on this results and their interpretation the optimal values of the parameters are determined to eliminate the unwanted process. The proposed approach overcomes the problems, causes of Low productivity and it improved the productivity

  18. Unsteady flow analysis of combustion processes in a Davis gun

    Energy Technology Data Exchange (ETDEWEB)

    Cho, H.-C.; Shin, H.D. [Korea Advanced Inst. of Science and Technology, Mechanical Engineering Dept., Taejon (Korea, Republic of); Yoon, J.-K. [Hansung Univ., School of Industrial and System Engineering, Seoul (Korea, Republic of)

    1999-09-01

    The Davis gun, a type of recoilless gun, had the advantages of requiring less rear area and less powder than a conventional recoilless gun. The unsteady pressure and flow fields of a Davis gun were numerically simulated by using a two-phase fluid dynamic model. Numerical simulation results were compared with experimental values to evaluate the feasibility of the interior ballistic model. The interior ballistics in a Davis gun with a simple countermass were predicted with the computational model. It was shown that the pressure-time curves matched well between experimental data and numerical analysis except in the vicinity of the peak pressure and steep pressure gradient. The predicted muzzle velocity of projectile and countermass was closely similar to the experimental one. In this study, large pressure waves were not observed since the initial porosity was relatively high ({phi}{sub 0}0.867) and the charge was ignited at the centre of the granular bed. (Author)

  19. Electrical Processes in a Flowing Plasma with Cold Electrodes

    International Nuclear Information System (INIS)

    The voltage-current characteristics of a flowing plasma between two electrodes is of interest for MHD power generation because of the high voltage drop necessary to make a current flow through the cool boundary layer of the plasma, lowering the efficiency of the MHD generator when the duct walls are cooled. The V-I characteristics are obtained for a combustion driven shock-tube generated plasma, and the voltage distribution is measured by probes inserted across the plasma. The gas used is argon and the plasma parameters are: T = 9000°K, p = 130 mmHg, u = 2500 m/sec, ne = 1.60 x 1015 cm-3. The probe technique has allowed experimental confirmation of the high voltage drop obtained in the vicinity of the cathode. A theoretical model has been set up in order to explain the main features of this phenomenon. The model considers the voltage drop along the following regions: the turbulent boundary layer and the viscous sublayer. The structure of the first two regions are taken into account according to the Coles transformation theory. The model considers three fluids, ions, electrons and neutrals: the mass and momentum particle conservation together with the Poisson equation and continuity of electric current allows us to set up a system of four differential equations with four unknowns. Pair production is taken into account in order to explain the necessary change over from electron current in the main body of the plasma to the predominantly ionic current in the neighbourhood of the cathode wall. Numerical computation of the system of equations has been done and the main features of the experimental results are explained. (author)

  20. Laminar flow and convective transport processes scaling principles and asymptotic analysis

    CERN Document Server

    Brenner, Howard

    1992-01-01

    Laminar Flow and Convective Transport Processes: Scaling Principles and Asymptotic Analysis presents analytic methods for the solution of fluid mechanics and convective transport processes, all in the laminar flow regime. This book brings together the results of almost 30 years of research on the use of nondimensionalization, scaling principles, and asymptotic analysis into a comprehensive form suitable for presentation in a core graduate-level course on fluid mechanics and the convective transport of heat. A considerable amount of material on viscous-dominated flows is covered.A unique feat

  1. On the application of kinematic models to simulate the diffusive processes of debris flows

    Science.gov (United States)

    Arattano, M.; Franzi, L.

    2010-08-01

    Debris flows generally propagate along steep mountain torrents with dynamics primarily governed by gravitational and frictional forces. Thus, debris flows modelling can be successfully performed through the application of kinematic models, which consider only the effects of slope and friction and neglect the remaining terms of the momentum equation. However, the diffusion processes that can be observed in the field, such as the spreading of the debris flow wave as it flows downstream, can not be theoretically predicted by kinematic models, since diffusion is a second-order process neglected in the kinematic approximation. In this paper, this issue is discussed and an application for both a generalized diffusion wave model and a kinematic model is proposed of a debris flow which occurred in an Italian instrumented torrent to identify, in a real case scenario, the effective value of the neglected terms in the kinematic approximation.

  2. On the application of kinematic models to simulate the diffusive processes of debris flows

    Directory of Open Access Journals (Sweden)

    M. Arattano

    2010-08-01

    Full Text Available Debris flows generally propagate along steep mountain torrents with dynamics primarily governed by gravitational and frictional forces. Thus, debris flows modelling can be successfully performed through the application of kinematic models, which consider only the effects of slope and friction and neglect the remaining terms of the momentum equation. However, the diffusion processes that can be observed in the field, such as the spreading of the debris flow wave as it flows downstream, can not be theoretically predicted by kinematic models, since diffusion is a second-order process neglected in the kinematic approximation. In this paper, this issue is discussed and an application for both a generalized diffusion wave model and a kinematic model is proposed of a debris flow which occurred in an Italian instrumented torrent to identify, in a real case scenario, the effective value of the neglected terms in the kinematic approximation.

  3. A study of bubble dynamics in subcooled flow boiling using image processing technique

    International Nuclear Information System (INIS)

    An experimental study of bubble dynamics in subcooled flow boiling was conducted using flow visualization and image processing methods. The flow pattern was recorded using a high speed cine camera and the resulting now images at any axial position were digitized in image analyzing system. A technique was developed to measure fundamental geometric parameters characterizing tile internal structure of bubble two-phase flow pattern such as: bubble size and shape, interfacial area, bubble growth or collapse position and velocity of the bubbles using image enhancement and segmentation techniques. The image was cleaned of noise using a set of image processing algorithms. These algorithms included background noise subtraction, contrast enhancement, median and smoothing filters and gray level thresholding and to be applied in that order for accurate evaluation and measurement of the fundamental parameters in two-phase, gas-liquid flows. (Original)

  4. Comparison of Inflation Processes at the 1859 Mauna Loa Flow, HI, and the McCartys Flow Field, NM

    Science.gov (United States)

    Bleacher, Jacob E.; Garry, W. Brent; Zimbelman, James R.; Crumpler, Larry S.

    2012-01-01

    Basaltic lavas typically form channels or tubes during flow emplacement. However, the importance of sheet flow in the development of basalt ic terrains received recognition over the last 15 years. George Walke r?s research on the 1859 Mauna Loa Flow was published posthumously in 2009. In this paper he discusses the concept of endogenous growth, or inflation, for the distal portion of this otherwise channeldominated lava flow. We used this work as a guide when visiting the 1859 flow to help us better interpret the inflation history of the McCartys flow field in NM. Both well preserved flows display similar clues about the process of inflation. The McCartys lava flow field is among the you ngest (approx.3000 yrs) basaltic lava flows in the continental United States. It was emplaced over slopes of inflation occurred. Although older than the 1859 flow, the McCartys is located in an arid environ ment and is among the most pristine examples of sheet flow morphologies. At the meter scale the flow surface typically forms smooth, undula ting swales that create a polygonal terrain. The literature for simil ar features includes multiple explanatory hypotheses, original breakouts from adjacent lobes, or inflation related upwarping of crust or sa gging along fractures that enable gas release. It is not clear which of these processes is responsible for polygonal terrains, and it is po ssible that one explanation is not the sole cause of this morphology between all inflated flows. Often, these smooth surfaces within an inflated sheet display lineated surfaces and occasional squeeze-ups alon g swale contacts. We interpret the lineations to preserve original fl ow direction and have begun mapping these orientations to better interpret the emplacement history. At the scale of 10s to 100s of meters t he flow comprises multiple topographic plateaus and depressions. Some depressions display level floors with surfaces as described above, while some are bowl shaped with floors covered in broken lava slabs. Th e boundaries between plateaus and depressions are also typically smoo th, grooved surfaces that have been tilted to angles sometimes approaching vertical. The upper margin of these tilted surfaces displays lar ge cracks, sometimes containing squeeze-ups. The bottom boundary with smooth floored depressions typically shows embayment by younger lavas. It appears that this style of terrain represents the emplacement of an extensive sheet that experiences inflation episodes within prefer red regions where lateral spreading of the sheet is inhibited, thereby forming plateaus. Depressions are often the result of non-inflation and can be clearly identified by lateral squeeze-outs along the pit walls that form when the rising crust exposes the still liquid core of the sheet. Our current efforts are focused on.

  5. UML Diagrams Generator: A New CASE Tool to Construct the Use-Case and Class Diagrams from an Event Table

    Directory of Open Access Journals (Sweden)

    Mohammad I. Muhairat

    2010-01-01

    Full Text Available Problem statement: Building UML diagrams is a very important and time consuming task for both requirements and design phases. However, some of these diagrams, such as use-case and class diagrams can be considered as a transition between the two phases. Approach: Through this study, the event table will be used to derive the use-case and class diagrams. Results: A new CASE tool to automate the proposed approach will be introduced, that is, the UML diagrams generator (UMLdg. Conclusion: It is clearly noted that the proposed CASE tool (UMLdg gives an ideal and reasonable methodology to construct the intended use-case and class diagrams from any comprehensive event table. Furthermore, this tool will save the time for the building process of such diagrams.

  6. Iron - binary phase diagrams

    International Nuclear Information System (INIS)

    This monography contains critically compiled equilibrium diagrams of binary systems of iron with all the elements of the Periodic Chart (except the halogens), updated and in an improved form (raster paper). It is based essentially on experimental data but includes the results of thermochemcial calculations where applicable. The work represents information up to the end of 1981. (GSCH)

  7. Plagioclase Phase Diagram

    Science.gov (United States)

    Dexter Perkins

    This is a short exercise aimed at evaluating whether students understand how to interpret the Ab-An phase diagram. If students know what is going on, it takes about 10 minutes to complete. This active learning exercise makes a good break from lecture. It is best done as a group activity.

  8. Balloons and Ray Diagrams

    Science.gov (United States)

    Michael Horton

    2009-05-30

    This inquiry activity will be students' first exposure to ray diagrams. They will be using the refraction of sound to simulate the refraction of light to introduce them to this concept. They will be creating a simulated convex lens with a CO 2 -f

  9. Measurement system of bubbly flow using ultrasonic velocity profile monitor and video data processing unit

    International Nuclear Information System (INIS)

    The authors have been developing a measurement system for bubbly flow in order to clarify its multi-dimensional flow characteristics and to offer a data base to validate numerical codes for multi-dimensional two-phase flow. In this paper, the measurement system combining an ultrasonic velocity profile monitor with a video data processing unit is proposed, which can measure simultaneously velocity profiles in both gas and liquid phases, a void fraction profile for bubbly flow in a channel, and an average bubble diameter and void fraction. Furthermore, the proposed measurement system is applied to measure flow characteristics of a bubbly countercurrent flow in a vertical rectangular channel to verify its capability. (author)

  10. Process Writing: Finding Flow in Adolescent Self-Expression.

    Science.gov (United States)

    Kinzer-Brackbill, Kim

    2001-01-01

    Describes one teacher's approach to process writing, a mainstay for Montessori adolescent classrooms. The premise of the method is that everyone has the natural potential to write and that the emergence of the inner voice must be nurtured by extended conferencing and revision combined with taking risks, experimenting, and continually revising.…

  11. Detecting flow processes in cracking clay soils through changes in the anisotropy of resistivity measurements

    Science.gov (United States)

    Greve, A. K.; Andersen, M. S.; Hartland, A.; Timms, W. A.; Acworth, R. I.

    2012-04-01

    Monitoring flow processes in cracking clay soils has remained a challenge. To overcome this, square array resistivity measurements and stable water isotopes were combined to investigate flow behaviour under cracked and non-cracked soil conditions. Depth profiles of ten 0.05 m spaced coplanar horizontal square arrays were installed in a weighing lysimeter filled with cracking clay soil. The initially dry and cracked soil profile was brought back to field capacity during two irrigation events, which were carried out with two water types with different isotope signatures. During the water applications time lapse series of electrical resistivity measurements with the ?, ?, and ? square arrays were collected and the anisotropy index and mean apparent resistivity were calculated for each measurement depth. The stable isotope composition of the collected effluent showed that water from the second irrigation bypassed the soil matrix with limited mixing. The observed bypass showed that even though the cracks at the soil surface were visually closed at the beginning of the second irrigation, preferential flow paths must have remained open. Monitoring changes in the directional dependence of square array resistivity measurements allowed further investigation of the flow processes. These measurements showed that throughout the irrigation events the dominant flow process changed from preferential flow to matrix flow. The use of square array resistivity measurements allowed for the first time to determine the exact timing of this transition. Matrix dominated flow did not occur until ponding water at the soil surface was observed. The onset of matrix flow started at the top of the profile and progressed downwards. The results show that time series square array resistivity measurements can be used to distinguish between soil moisture and cracking stages as well as between water migration processes within a soil profile. This will provide valuable insight during the investigation of the complex water migration processes in cracking soils.

  12. Vista Data Flow System: Pipeline Processing for WFCAM and VISTA

    Science.gov (United States)

    Lewis, J. R.; Irwin, M. J.; Hodgkin, S. T.; Bunclark, P. S.; Evans, D. W.; McMahon, R. G.

    2005-12-01

    The UKIRT Wide Field Camera (WFCAM) on Mauna Kea and the VISTA IR mosaic camera at ESO, Paranal, with respectively 4 Rockwell 2k × 2k and 16 Raytheon 2k × 2k IR arrays on 4m-class telescopes, represent an enormous leap in deep IR survey capability. However with an expected data rate of an image of the sky every 5-30s and combined nightly data-rates of typically 1 TB, automated pipeline processing and data management requirements are paramount. Pipeline processing of IR data is far more technically challenging than for optical data. IR detectors are inherently more unstable, while the sky emission is over 100 times brighter than most objects of interest, and varies in a complex spatial and temporal manner. The pipelines are designed around a selectable modular scheme, driven by processing recipes for maximum flexibility. Our general philosophy is that all fundamental data products are in multi-extension FITS files with headers describing the data taking protocols in sufficient detail to trigger the appropriate pipeline processing components. All derived information, DQC, photometric and astrometric calibration and processing details are also incorporated into the FITS headers. Generated catalogues are stored in FITS binary tables. The headers provide a basis for ingest into databases for archiving, real time monitoring of survey progress and survey planning. To reduce the data storage I/O overheads and transport requirements, we intend to use, as much as possible, the lossless Rice tile compression scheme as used transparently, for example, in CFITSIO. For this type of data (32 bit integer) the algorithm typically gives a factor of 3-4 compression

  13. Laser Doppler blood flow complementary metal oxide semiconductor imaging sensor with analog on-chip processing

    International Nuclear Information System (INIS)

    A 4x4 pixel array with analog on-chip processing has been fabricated within a 0.35 ?m complementary metal oxide semiconductor process as a prototype sensor for laser Doppler blood flow imaging. At each pixel the bandpass and frequency weighted filters necessary for processing laser Doppler blood flow signals have been designed and fabricated. Because of the space constraints of implementing an accurate ?0.5 filter at the pixel level, this has been approximated using the ''roll off'' of a high-pass filter with a cutoff frequency set at 10 kHz. The sensor has been characterized using a modulated laser source. Fixed pattern noise is present that is demonstrated to be repeatable across the array and can be calibrated. Preliminary blood flow results on a finger before and after occlusion demonstrate that the sensor array provides the potential for a system that can be scaled to a larger number of pixels for blood flow imaging

  14. Semantic mediation of information flow in cross-organizational business process modeling

    OpenAIRE

    Barnickel, N.; Bo?ttcher, J.; Paschke, A.

    2010-01-01

    In this paper we propose a mediated business process modeling approach, where ontology-based information models are used for the semantic modeling of information flow in cross-organizational business processes. Rule-based semantic bridges are applied for the automated mediation between different domain vocabularies used in the organizations' process models. This allows for interchange and interconnection of business process models, as well as for mediation between the abstract business level ...

  15. Equivalent Temperature-Enthalpy Diagram for the Study of Ejector Refrigeration Systems

    Directory of Open Access Journals (Sweden)

    Mohammed Khennich

    2014-05-01

    Full Text Available The Carnot factor versus enthalpy variation (heat diagram has been used extensively for the second law analysis of heat transfer processes. With enthalpy variation (heat as the abscissa and the Carnot factor as the ordinate the area between the curves representing the heat exchanging media on this diagram illustrates the exergy losses due to the transfer. It is also possible to draw the paths of working fluids in steady-state, steady-flow thermodynamic cycles on this diagram using the definition of “the equivalent temperature” as the ratio between the variations of enthalpy and entropy in an analyzed process. Despite the usefulness of this approach two important shortcomings should be emphasized. First, the approach is not applicable for the processes of expansion and compression particularly for the isenthalpic processes taking place in expansion valves. Second, from the point of view of rigorous thermodynamics, the proposed ratio gives the temperature dimension for the isobaric processes only. The present paper proposes to overcome these shortcomings by replacing the actual processes of expansion and compression by combinations of two thermodynamic paths: isentropic and isobaric. As a result the actual (not ideal refrigeration and power cycles can be presented on equivalent temperature versus enthalpy variation diagrams. All the exergy losses, taking place in different equipments like pumps, turbines, compressors, expansion valves, condensers and evaporators are then clearly visualized. Moreover the exergies consumed and produced in each component of these cycles are also presented. The latter give the opportunity to also analyze the exergy efficiencies of the components. The proposed diagram is finally applied for the second law analysis of an ejector based refrigeration system.

  16. Stochastic flows, reaction-diffusion processes, and morphogenesis

    International Nuclear Information System (INIS)

    Recently, an exact procedure has been introduced [C. A. Walsh and J. J. Kozak, Phys. Rev. Lett.. 47: 1500 (1981)] for calculating the expected walk length for a walker undergoing random displacements on a finite or infinite (periodic) d-dimensional lattice with traps (reactive sites). The method (which is based on a classification of the symmetry of the sites surrounding the central deep trap and a coding of the fate of the random walker as it encounters a site of given symmetry) is applied here to several problems in lattice statistics for each of which exact results are presented. First, we assess the importance of lattice geometry in influencing the efficiency of reaction-diffusion processs in simple and multiple trap systems by reporting values of for square (cubic) versus hexagonal lattices in d = 2,3. We then show how the method may be applied to variable-step (distance-dependent) walks for a single walker on a given lattice and also demonstrate the calculation of the expected walk length for the case of multiple walkers. Finally, we make contact with recent discussions of ''mixing'' by showing that the degree of chaos associated with flows in certain lattice-systems can be calibrated by monitoring the lattice walks induced by the Poincare map of a certain parabolic function

  17. Genealogy of flows of continuous-state branching processes via flows of partitions and the Eve property

    OpenAIRE

    Labbe?, Cyril

    2012-01-01

    We encode the genealogy of a continuous-state branching process associated with a branching mechanism $\\Psi$ - or $\\Psi$-CSBP in short - using a stochastic flow of partitions. This encoding holds for all branching mechanisms and appears as a very tractable object to deal with asymptotic behaviours and convergences. In particular we study the so-called Eve property - the existence of an ancestor from which the entire population descends asymptotically - and give a necessary a...

  18. New attachment for controlling gas flow in the HVOF process

    Science.gov (United States)

    Dolatabadi, A.; Pershin, V.; Mostaghimi, J.

    2005-03-01

    During the decade, the high-velocity oxyfuel (HVOF) process proved to be a technological alternative to the many conventional thermal spray processes. It would be very advantageous to design a nozzle that provides improved performance in the areas of deposition efficiency, particle in-flight oxidation, and flexibility to allow deposition of ceramic coatings. Based on a numerical analysis, a new attachment to a standard HVOF torch was modeled, designed, tested, and used to produce thermal spray coatings according to the industrial needs mentioned above. Performance of the attachment was investigated by spraying several coating materials including metal and ceramic powders. Particle conditions and spatial distribution, as well as gas phase composition, corresponding to the new attachment and the standard HVOF gun, were compared. The attachment provides better particle spatial distribution, combined with higher particle velocity and temperature.

  19. Improving product flow and storage in a timber processing facility

    OpenAIRE

    Marais, Su-anrie

    2012-01-01

    York Timbers Pty Ltd is a South African timber processing company that has four saw mills in the Mpumalanga province. York Timbers manufacture high quality timber products for local and international markets. All four saw mills are controlled and monitored by their head office in Sabie, Mpumalanga. Recently it has been observed that the Driekop dry mill in Graskop cannot fulfil all the orders that are received resulting from limited or no availability of products. Each saw mill has amon...

  20. VennDiagram: a package for the generation of highly-customizable Venn and Euler diagrams in R

    Directory of Open Access Journals (Sweden)

    Boutros Paul C

    2011-01-01

    Full Text Available Abstract Background Visualization of orthogonal (disjoint or overlapping datasets is a common task in bioinformatics. Few tools exist to automate the generation of extensively-customizable, high-resolution Venn and Euler diagrams in the R statistical environment. To fill this gap we introduce VennDiagram, an R package that enables the automated generation of highly-customizable, high-resolution Venn diagrams with up to four sets and Euler diagrams with up to three sets. Results The VennDiagram package offers the user the ability to customize essentially all aspects of the generated diagrams, including font sizes, label styles and locations, and the overall rotation of the diagram. We have implemented scaled Venn and Euler diagrams, which increase graphical accuracy and visual appeal. Diagrams are generated as high-definition TIFF files, simplifying the process of creating publication-quality figures and easing integration with established analysis pipelines. Conclusions The VennDiagram package allows the creation of high quality Venn and Euler diagrams in the R statistical environment.

  1. Sn60Pb40 solder powders produced by the planar flow casting atomization process

    Directory of Open Access Journals (Sweden)

    Xiang Qingchun

    2011-05-01

    Full Text Available Conventional planar flow casting (PFC is one of rapid solidification processes for the fabrication of microcrystalline or amorphous ribbons. Based on the conventional PFC process, the planar flow casting atomization (PFCA process has been developed, which is a new rapid solidification process for the production of metal powder directly from alloy melts. A prototype experimental apparatus was designed and manufactured. With the apparatus, Sn60Pb40 alloy solder powders were prepared, and the effects of the main technological parameters on the powder size distribution and morphology were experimentally studied. The experimental investigations indicate that the metal powders produced by the PFCA process can be classified by velocity; and fine spherical tin-lead alloy solder powders can be fabricated by adjusting the technical parameters. The new PFCA process has such features as high productivity and efficiency, low energy consumption, simple operation, short technological process, and large gross yield.

  2. Influence diagram in evaluating the subjective judgment

    International Nuclear Information System (INIS)

    The author developed the idea of the subjective influence diagrams to evaluate subjective judgment. The subjective judgment of a stake holder is a primary decision making proposition. It involves a basic decision process an the individual attitude of the stake holder for his decision purpose. The subjective judgment dominates the some final decisions. A complex decision process may include the subjective judgment. An influence diagram framework is a simplest tool for analyzing subjective judgment process. In the framework, the characters of influence diagrams generate the describing the analyzing, and the evaluating of the subjective judgment. The relationship between the information and the decision, such as independent character between them, is the main issue. Then utility function is the calculating tool to evaluation, the stake holder can make optimal decision. Through the analysis about the decision process and relationship, the building process of the influence diagram identically describes the subjective judgment. Some examples are given to explain the property of subjective judgment and the analysis process

  3. Study on Flow Stress Model and Processing Map of Homogenized Mg-Gd-Y-Zn-Zr Alloy During Thermomechanical Processes

    Science.gov (United States)

    Xue, Yong; Zhang, Zhimin; Lu, Guang; Xie, Zhiping; Yang, Yongbiao; Cui, Ya

    2015-02-01

    Quantities of billets were compressed with 50% height reduction on a hot process simulator to study the plastic flow behaviors of homogenized as-cast Mg-13Gd-4Y-2Zn-0.6Zr alloy. The test alloy was heat treated at 520 °C for 12 h before thermomechanical experiments. The temperature of the processes ranged from 300 to 480 °C. The strain rate was varied between 0.001 and 0.5 s-1. According to the Arrhenius type equation, a flow stress model was established. In this model, flow stress was regarded as the function of the stress peak, strain peak, and the strain. A softening factor was used to characterize the dynamic softening phenomenon that occurred in the deformation process. Meanwhile, the processing maps based on the dynamic material modeling were constructed. The optimum temperature and strain rate for hot working of the test alloy were 480 °C and 0.01 s-1, respectively. Furthermore, the flow instability occurred in the two areas where the temperature ranged from 350 to 480 °C at strain rate of 0.01-0.1 s-1, and the temperature ranged from 450 to 480 °C with a strain rate of 0.1 s-1. According to the determined hot deformation parameters, four components were successfully formed, and the ultimate tensile strength, yield strength, and elongation of the component were 386 MPa, 331 MPa, and 6.3%, respectively.

  4. A self-sustaining nonlinear dynamo process in Keplerian shear flows

    CERN Document Server

    Rincon, F; Proctor, M R E

    2007-01-01

    A three-dimensional nonlinear dynamo process is identified in rotating plane Couette flow in the Keplerian regime. It is analogous to the hydrodynamic self-sustaining process in non-rotating shear flows and relies on the magneto-rotational instability of a toroidal magnetic field. Steady nonlinear solutions are computed numerically for a wide range of magnetic Reynolds numbers but are restricted to low Reynolds numbers. This process may be important to explain the sustenance of coherent fields and turbulent motions in Keplerian accretion disks, where all its basic ingredients are present.

  5. Voronoi Diagram Generation Algorithm based on Delaunay Triangulation

    OpenAIRE

    Liping Sun; Yonglong Luo; Yalei Yu; Xintao Ding

    2014-01-01

    Voronoi diagram and its geometric dual, the Delaunay triangulation, both are practical geometric constructions which have been applied extensively in spatial analysis. Considering the low efficiency of the algorithm of indirectly building Voronoi diagram, this paper proposes an improved Voronoi diagram generation algorithm based on Delaunay triangulation of randomly distributed points in the Euclidean plane. In the process of building Delaunay triangulation, correlative edges of points and co...

  6. Numerical modelling of the nonequilibrium expansion process of argon plasma flow through a nozzle

    International Nuclear Information System (INIS)

    A two-temperature thermal and chemical nonequilibrium model is developed and applied to investigate the expansion processes of an argon plasma flow through a Laval nozzle. This model describes in a self-consistent manner the gas flow and heat transfer, the coupling of the electric energy deposited into the plasma, and the reaction kinetics including the contribution of excited species. It is found that the plasma is far from thermodynamic equilibrium in the entire argon plasma flow expansion process through a nozzle. Significant temperature discrepancies between electrons and heavy species are found in the cooler outer region. The dominant chemical kinetic processes in different plasma gas expansion regions are presented and discussed. It is noted that although the number density of excited argon atoms (Ar*) is much lower than that of other species in the argon plasma, Ar* play important roles in the ionization and recombination processes, and in arc attachment to the anode. (paper)

  7. Diagrams as Tools for Worldmaking.

    Science.gov (United States)

    Poggenpohl, Sharon Helmer; Winkler, Dietmar R.

    1992-01-01

    Steps aside from conventional ideas about diagrams to examine how they work. Brings to bear ideas from a perceptual psychologist, a communication theorist, and a philosopher. Introduces the papers in this special issue as diagrams for worldmaking. (SR)

  8. Micro-particle image velocimetry measurement of blood flow: validation and analysis of data pre-processing and processing methods

    International Nuclear Information System (INIS)

    The intent of this paper is to investigate the application of a pre-processing method previously validated on glycerol to blood flows in microchannels and to compare the accuracy of results obtained when applied to a non-homogeneous fluid such as blood with results from previously applied processing methods for blood data. Comparisons of common processing methods are desired for a clear measure of accuracy in order to make recommendations for various flows. It is hypothesized that increasing the correlation window overlap improves the profile prediction. The amount of correlation window overlap and window shape in the processing of data have a significant effect on the results. Image pre-processing is explored to improve the correlation using the ‘image overlapping’ which is extended to the case of blood and the blood-specific pre-processing ‘base-clipping’ or ‘thresholding’ technique currently applied to blood. Both pre-processing methods are tested with multiple processing methods for two channel geometries: a straight rectangular channel and a Y-channel resulting in a controlled shear flow. The resulting profiles and calculations demonstrate that ‘image-overlapping’ is found to achieve a profile closer to the predicted theoretical profile than current blood pre-processing methods when both are applied to the same set of data and both are superior to conventional cross-correlation on its own. In all cases, pre-processing decreases the smoothness of the predicted profile. The use of ‘image-overlapping’ is shown to have greater accuracy when calculating the shear rate at the wall of the channel as well. (paper)

  9. Peircean diagrams of time

    DEFF Research Database (Denmark)

    ØhrstrØm, Peter

    2011-01-01

    Some very good arguments can be given in favor of the Augustinean wisdom, according to which it is impossible to provide a satisfactory definition of the concept of time. However, even in the absence of a proper definition, it is possible to deal with conceptual problems regarding time. It can be done in terms of analogies and metaphors. In particular, it is attractive to make use of Peirce's diagrams by means of which various kinds of conceptual experimentation can be carried out. This paper investigates how Peircean diagrams can be used within the study of time. In particular, we discuss 1) the topological properties of time, 2) the implicative structure in tense logic, 3) the notions of open future and branching time models, and finally 4) tenselogical alternatives to branching time models.

  10. Boolean Expression Diagrams

    DEFF Research Database (Denmark)

    Andersen, Henrik Reif; Hulgaard, Henrik

    2002-01-01

    This paper presents a new data structure called boolean expression diagrams (BEDs) for representing and manipulating Boolean functions. BEDs are a generalization of binary decision diagrams (BDDs) which can represent any Boolean circuit in linear space. Two algorithms are described for transforming a BED into a reduced ordered BDD. One is a generalized version of the BDD apply-operator while the other can exploit the structural information of the Boolean expression. This ability is demonstrated by verifying that two different circuit implementations of a 16-bit multiplier implement the same Boolean function. Using BEDs, this verification problem is solved efficiently, while using standard BDD techniques this problem is infeasible. Generally, BEDs are useful in applications, for example tautology checking, where the end-result as a reduced ordered BDD is small. Moreover, using operators for substitution and existential quantification they allow for the verification of large hierarchical circuits.

  11. Homotopy Diagrams of Algebras

    OpenAIRE

    Markl, Martin

    2001-01-01

    In [math.AT/9907138] we proved that strongly homotopy algebras are homotopy invariant concepts in the category of chain complexes. Our arguments were based on the fact that strongly homotopy algebras are algebras over minimal cofibrant operads and on the principle that algebras over cofibrant operads are homotopy invariant. In our approach, algebraic models for colored operads describing diagrams of homomorphisms played an important role. The aim of this paper is to give a...

  12. Analysis of different water-sediment flow processes in a mountain torrent

    Directory of Open Access Journals (Sweden)

    M. Arattano

    2004-01-01

    Full Text Available Sediment – water flows occurring in mountain torrents may show a variety of regimes, ranging from water flows with transport of individual particles to massive transport of debris, as it occurs in case of debris flows. Sometimes it is possible, by means of accurate field investigations, to identify the kind of processes that took place in a torrent after the occurrence of an event. However this procedure cannot give indications regarding the development of the process in time. In fact, because of the frequent presence of different surges within the same event, the rheological characteristics of an event can be detected only when some recorded hydrographs or videos are available. For the same reason, since the rheological behaviour of the flow changes according to the solid concentration, the analysis of the materials deposited on the debris fan cannot directly give any information on the particular types of flow that took place: a possible alternation in time of different water sediment surges with different concentrations may have occurred, during the same event. The installation of ultrasonic gauges or videocameras along the torrent might give more information on this issue. To this regard, the analysis of a flow event which occurred in 2002 in the Moscardo torrent watershed, instrumented for debris flow monitoring, has been undertaken, studying the hydrographs recorded at two different ultrasonic gauges placed at a known distance along the torrent. An empirical flow resistance law has been applied analysing the values assumed by its parameters after calibration. The application of this law actually spans from debris flow and immature debris flow to bed load transport. Only field observations and surveys, together with ultrasonic data, may allow to clearly discriminate which type of flow really occurred. The analysis confirms that different water sediment surges alternated in time while the mathematical simulation of the flow compared with field observations revealed that the dynamic behaviour of the flow was different from that of previous debris flow events and might reflect, among the different types of possible rheological behaviors, a dilatant-type behavior typical of stony debris flows.

  13. On the self-organizing process of large scale shear flows

    Energy Technology Data Exchange (ETDEWEB)

    Newton, Andrew P. L. [Department of Applied Maths, University of Sheffield, Sheffield, Yorkshire S3 7RH (United Kingdom); Kim, Eun-jin [School of Mathematics and Statistics, University of Sheffield, Sheffield, Yorkshire S3 7RH (United Kingdom); Liu, Han-Li [High Altitude Observatory, National Centre for Atmospheric Research, P. O. BOX 3000, Boulder, Colorado 80303-3000 (United States)

    2013-09-15

    Self organization is invoked as a paradigm to explore the processes governing the evolution of shear flows. By examining the probability density function (PDF) of the local flow gradient (shear), we show that shear flows reach a quasi-equilibrium state as its growth of shear is balanced by shear relaxation. Specifically, the PDFs of the local shear are calculated numerically and analytically in reduced 1D and 0D models, where the PDFs are shown to converge to a bimodal distribution in the case of finite correlated temporal forcing. This bimodal PDF is then shown to be reproduced in nonlinear simulation of 2D hydrodynamic turbulence. Furthermore, the bimodal PDF is demonstrated to result from a self-organizing shear flow with linear profile. Similar bimodal structure and linear profile of the shear flow are observed in gulf stream, suggesting self-organization.

  14. Post-Processing of Discrete Flow Field Data for Particle Tracking Velocimetry

    Directory of Open Access Journals (Sweden)

    Wang Pengtao

    2013-01-01

    Full Text Available To measure the surface flow in a physical river model, a brief introduction was given to the method of Particle Tracking Velocimetry (PTV. According to the characteristics of PTV by seeding particles on the water surface, particle images can be captured by CCD cameras and recognized by image division. PTV algorithm gives one vector for each particle based on the principle the trajectory of an individual particle is continuous. The key problem of analyzing the flow speed field accurately is post-processing of discrete flow field data. Errors of measurement discrete data are removed by the basic law of water movement. To attain the whole flow speed field, the methods of interpolation of discrete flow field data were proposed. In addition, the graphics of streamlines, velocity isolines and vortex isolines were drawn by the theory of hydraulic calculation.

  15. Investigation of Multiscale and Multiphase Flow, Transport and Reaction in Heavy Oil Recovery Processes

    Energy Technology Data Exchange (ETDEWEB)

    Yortsos, Y.C.

    2001-05-29

    This report is an investigation of various multi-phase and multiscale transport and reaction processes associated with heavy oil recovery. The thrust areas of the project include the following: Internal drives, vapor-liquid flows, combustion and reaction processes, fluid displacements and the effect of instabilities and heterogeneities and the flow of fluids with yield stress. These find respective applications in foamy oils, the evolution of dissolved gas, internal steam drives, the mechanics of concurrent and countercurrent vapor-liquid flows, associated with thermal methods and steam injection, such as SAGD, the in-situ combustion, the upscaling of displacements in heterogeneous media and the flow of foams, Bingham plastics and heavy oils in porous media and the development of wormholes during cold production.

  16. Legendrian graphs and quasipositive diagrams

    CERN Document Server

    Baader, S; Baader, Sebastian; Ishikawa, Masaharu

    2006-01-01

    In this paper we clarify the relationship between ribbon surfaces of Legendrian graphs and quasipositive diagrams by using certain fence diagrams. As an application, we give an alternative proof of a theorem concerning a relationship between quasipositive fiber surfaces and contact structures on the 3-sphere. We also answer a question of L. Rudolph concerning moves of quasipositive diagrams.

  17. Ring diagrams and phase transitions

    International Nuclear Information System (INIS)

    Ring diagrams at finite temperatures carry most infrared-singular parts among Feynman diagrams. Their effect to effective potentials are in general so significant that one must incorporate them as well as 1-loop diagrams. The author expresses these circumstances in some examples of supercooled phase transitions

  18. Non-Linear Flow Process (NLFP): a new package implementing the Forchheimer equation in MODFLOW

    Science.gov (United States)

    Mayaud, Cyril; Walker, Patrica; Hergarten, Stefan; Birk, Steffen

    2014-05-01

    Groundwater flow in porous media is usually considered to be laminar and to follow Darcy's law (i.e. a linear relationship between the specific discharge and the hydraulic gradient). However, flow can become non-linear or turbulent if a critical Reynolds number is exceeded. This is known to occur, for example, within the solution conduits of karst aquifers or in the vicinity of pumping wells. As most of the existing distributive groundwater models such as MODFLOW-2005 are based on Darcy's law, there is a lack of tools accounting for the non-linear or turbulent flow conditions encountered in these settings. For this reason, a new MODFLOW package (Non-Linear Flow Process; NLFP) simulating non-linear flow following the Forchheimer equation was developed and implemented in MODLFOW-2005. This package is essentially based on an iterative modification of the linear conductance used by MODFLOW. The resulting effective Forchheimer conductance decreases with increasing specific discharge and thus mimics the effect of the non-linear term of the Forchheimer equation. The method was implemented such that the different layer types, boundaries conditions, and solvers as well as the wetting capability of MODFLOW are supported. The NLFP package was also successfully integrated in the current version of the conduit flow process CFP (Shoemaker et al., U.S. Geological Survey Techniques and Methods 6-A24, 2008). The correct implementation of the package is demonstrated using three different benchmark scenarios for which analytical solutions are available. Finally, a scenario considering transient flow in a more realistic karst setting and a larger model grid demonstrates that NLFP performs well under more complex conditions, although it converges moderately slower than the standard MODFLOW depending on the non-linearity of flow. Thus, this new tool opens a field of opportunities to non-linear groundwater flow simulation with MODFLOW-2005, especially for core sample simulation or vuggy karstified aquifers as well as for non-linear flow in vicinity of pumping wells.

  19. Application of radioisotope techniques to control flow process during artificial coastal aquifer recharge

    International Nuclear Information System (INIS)

    Radioisotope techniques was applied for studying the flow and transport processes in a coastal confined aquifer during an artificial recharge experiment to check the feasibility of controlling salt water intrusion by a hydrodynamic barrier. As no other water source is available, artificial recharge is done using treated wastewaters. Flow and effective velocity, hydraulic conductivity, transmissivity, diffusivity and effective porosity have been determined by means of I-131 radioisotope in single- and multi-well tests. (author)

  20. Effect of Inlet and Outlet Flow Conditions on Natural Gas Parameters in Supersonic Separation Process

    OpenAIRE

    Yang, Yan; Wen, Chuang; Wang, Shuli; Feng, Yuqing

    2014-01-01

    A supersonic separator has been introduced to remove water vapour from natural gas. The mechanisms of the upstream and downstream influences are not well understood for various flow conditions from the wellhead and the back pipelines. We used a computational model to investigate the effect of the inlet and outlet flow conditions on the supersonic separation process. We found that the shock wave was sensitive to the inlet or back pressure compared to the inlet temperature. The shock position s...

  1. Expanding the toolbox of asymmetric organocatalysis by continuous-flow process.

    Science.gov (United States)

    Finelli, Fernanda G; Miranda, Leandro S M; de Souza, Rodrigo O M A

    2015-03-01

    Despite all the organic chemistry reaction methodologies already developed for the continuous-flow process, asymmetric synthesis is one that has gained less attention. Since the pioneering work of Barbas and MacMillan, organocatalysis has emerged as the third pillar of asymmetric catalysis. In this review, we present a survey of literature regarding the use of organocatalysis under continuous-flow conditions. PMID:25585518

  2. Dynamic relaxation processes in compressible multiphase flows. Application to evaporation phenomena

    OpenAIRE

    Le Métayer O.; Massoni J.; Saurel R.

    2013-01-01

    Phase changes and heat exchanges are examples of physical processes appearing in many industrial applications involving multiphase compressible flows. Their knowledge is of fundamental importance to reproduce correctly the resulting effects in simulation tools. A fine description of the flow topology is thus required to obtain the interfacial area between phases. This one is responsible for the dynamics and the kinetics of heat and mass transfer when evaporation or condensation occurs. U...

  3. Analysis of nuclear material flow for experimental DUPIC fuel fabrication process at DFDF

    International Nuclear Information System (INIS)

    This report describes facilities necessary for manufacturing experiment for DUPIC fuel, manufacturing process and equipment. Nuclear material flows among facilities, in PIEF and IMEF, for irradiation test, for post examination of DUPIC fuel, for quality control, for chemical analysis and for treatment of radioactive waste have been analyzed in details. This may be helpful for DUPIC project participants and facility engineers working in related facilities to understand overall flow for nuclear material and radioactive waste. (Author). 14 refs., 15 tabs., 41 figs

  4. Analysis of nuclear material flow for experimental DUPIC fuel fabrication process at DFDF

    Energy Technology Data Exchange (ETDEWEB)

    Lee, H. H.; Park, J. J.; Shin, J. M.; Lee, J. W.; Yang, M. S.; Baik, S. Y.; Lee, E. P

    1999-08-01

    This report describes facilities necessary for manufacturing experiment for DUPIC fuel, manufacturing process and equipment. Nuclear material flows among facilities, in PIEF and IMEF, for irradiation test, for post examination of DUPIC fuel, for quality control, for chemical analysis and for treatment of radioactive waste have been analyzed in details. This may be helpful for DUPIC project participants and facility engineers working in related facilities to understand overall flow for nuclear material and radioactive waste. (Author). 14 refs., 15 tabs., 41 figs.

  5. A filtered renewal process as a model for a river flow

    OpenAIRE

    Lefebvre Mario

    2005-01-01

    Various models, based on a filtered Poisson process, are used for the flow of a river. The aim is to forecast the next peak value of the flow, given that another peak was observed not too long ago. The most realistic model is the one when the time between the successive peaks does not have an exponential distribution, as is often assumed. An application to the Delaware River, in the USA, is presented.

  6. Efficient Boolean and multi-input flow techniques for advanced mask data processing

    Science.gov (United States)

    Salazar, Daniel; Moore, Bill; Valadez, John

    2012-11-01

    Mask data preparation (MDP) typically involves multiple flows, sometimes consisting of many steps to ensure that the data is properly written on the mask. This may include multiple inputs, transformations (scaling, orientation, etc.), and processing (layer extraction, sizing, Boolean operations, data filtering). Many MDP techniques currently in practice require multiple passes through the input data and/or multiple file I/O steps to achieve these goals. This paper details an approach which efficiently process the data, resulting in minimal I/O and greatly improved turnaround times (TAT). This approach takes advanced processing algorithms and adapts them to produce efficient and reliable data flow. In tandem with this processing flow, an internal jobdeck mapping approach, transparent to the user, allows an essentially unlimited number of pattern inputs to be handled in a single pass, resulting in increased flexibility and ease of use. Transformations and processing operations are critical to MDP. Transformations such as scaling, reverse tone and orientation, along with processing including sizing, Boolean operations and data filtering are key parts of this. These techniques are often employed in sequence and/or in parallel in a complex functional chain. While transformations typically are done "up front" when the data is input, processing is less straightforward, involving multiple reads and writes to handle the more intricate functionality and also the collection of input patterns which may be required to produce the data that comprises a single mask. The approach detailed in this paper consists of two complementary techniques: efficient MDP flow and jobdeck mapping. Efficient MDP flow is achieved by pipelining the output of each step to the input of the subsequent step. Rather than writing the output of a particular processing step to file and then reading it in to the following step, the pipelining or chaining of the steps results in an efficient flow with minimal file I/O. The efficient MDP flow is enhanced by a technique called jobdeck mapping which allows in essence an unlimited number of pattern inputs by taking each transformed pattern and including it in an input jobdeck. Making use of established jobdeck handling capabilities, the user-selected input pattern/transformation combinations are mapped to an input jobdeck which is processed by the advanced flow, allowing great flexibility and user control of the process.

  7. Laser Doppler blood flow imaging using a CMOS imaging sensor with on-chip signal processing

    OpenAIRE

    Cally Gill; Clough, Geraldine F.; Morgan, Stephen P.; Hayes-gill, Barrie R.; Crowe, John A.; Yiqun Zhu; Nguyen, Hoang C.; Diwei He

    2013-01-01

    The first fully integrated 2D CMOS imaging sensor with on-chip signal processing for applications in laser Doppler blood flow (LDBF) imaging has been designed and tested. To obtain a space efficient design over 64 × 64 pixels means that standard processing electronics used off-chip cannot be implemented. Therefore the analog signal processing at each pixel is a tailored design for LDBF signals with balanced optimization for signal-to-noise ratio and silicon area. This custom made sensor offe...

  8. Taming hazardous chemistry in flow: the continuous processing of diazo and diazonium compounds.

    Science.gov (United States)

    Deadman, Benjamin J; Collins, Stuart G; Maguire, Anita R

    2015-02-01

    The synthetic utilities of the diazo and diazonium groups are matched only by their reputation for explosive decomposition. Continuous processing technology offers new opportunities to make and use these versatile intermediates at a range of scales with improved safety over traditional batch processes. In this minireview, the state of the art in the continuous flow processing of reactive diazo and diazonium species is discussed. PMID:25404044

  9. Materials And Carbon Flow In A Waste Refinery Process Using Enzymes

    OpenAIRE

    Tonini, Davide; Woods, M.; Astrup, Thomas

    2011-01-01

    Recovery of resources from mixed Municipal Solid Waste (MSW) is a crucial aspect of waste management practices. In this paper the materials and carbon flows of an innovative waste refinery process using enzymes are presented. Through enzymatic treatment the process produces two main streams from the initial mixed MSW: a bioslurry (liquefied paper and organics) and a solid fraction (non-degradable materials). The discussion is based on the performance of the process in separating recyclables a...

  10. Image Processing for Bubble Departure Frequency in a Subcooled Boiling Flow

    Energy Technology Data Exchange (ETDEWEB)

    Euh, D. J. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Ozarb, B.; Hibikib, T.; Ishiib, M. [School of Nuclear Engineering, Purdue University, West Lafayette (United States)

    2009-05-15

    For the subcooled boiling problem, a bubble departure due to nucleate boiling acts as an important mechanism in a mechanistic analysis for the two-phase flow in the form of a boundary condition. Few works have been performed for an experiment and modeling of a bubble departure frequency under a convective flow boiling. The purpose of this paper is to develop an image process method by a visualization of the bubble nucleation and to study the bubble departure frequency in a vertical upward forced-convective subcooled boiling flow. The generated data are compared with previous models and a new model is proposed.

  11. Towards an optimized flow-sheet for a SANEX demonstration process using centrifugal contactors

    International Nuclear Information System (INIS)

    The design of an efficient process flow-sheet requires accurate extraction data for the experimental set-up used. Often this data is provided as equilibrium data. Due to the small hold-up volume compared to the flow rate in centrifugal contactors the time for extraction is often too short to reach the equilibrium D-ratios. In this work single stage kinetics experiments have been carried out to investigate the D-ratio dependence of the flow rate and also to compare with equilibrium batch experiments for CyMe4- BTBP. The first centrifuge experiment was run with spiked solutions while in the second a genuine actinide/lanthanide fraction from a TODGA process was used. Three different flow rates were tested with each set-up. The results show that even with low flow rates, around 8% of the equilibrium D-ratio (Am) was reached for the extraction in the spiked test and around 16% in the hot test (the difference is due to the size of the centrifuges). The general conclusion is that the development of a process flow sheet needs investigation of the kinetic behaviour in the actual equipment used. (authors)

  12. Online traffic flow model applying dynamic flow-density relation

    International Nuclear Information System (INIS)

    This dissertation describes a new approach of the online traffic flow modelling based on the hydrodynamic traffic flow model and an online process to adapt the flow-density relation dynamically. The new modelling approach was tested based on the real traffic situations in various homogeneous motorway sections and a motorway section with ramps and gave encouraging simulation results. This work is composed of two parts: first the analysis of traffic flow characteristics and second the development of a new online traffic flow model applying these characteristics. For homogeneous motorway sections traffic flow is classified into six different traffic states with different characteristics. Delimitation criteria were developed to separate these states. The hysteresis phenomena were analysed during the transitions between these traffic states. The traffic states and the transitions are represented on a states diagram with the flow axis and the density axis. For motorway sections with ramps the complicated traffic flow is simplified and classified into three traffic states depending on the propagation of congestion. The traffic states are represented on a phase diagram with the upstream demand axis and the interaction strength axis which was defined in this research. The states diagram and the phase diagram provide a basis for the development of the dynamic flow-density relation. The first-order hydrodynamic traffic flow model was programmed according to the cell-transmission scheme extended by the modification of flow dependent sending/receiving functions, the classification of cells and the determination strategy for the flow-density relation in the cells. The unreasonable results of macroscopic traffic flow models, which may occur in the first and last cells in certain conditions are alleviated by applying buffer cells between the traffic data and the model. The sending/receiving functions of the cells are determined dynamically based on the classification of the traffic states by employing fuzzy logic and the shock wave theory. The model is extended to describe also the propagation of congestion in the motorway sections with ramps by considering the capacity reduction caused by the interaction between the traffic flow of the mainstream and the ramps. This research represents the potential of the macroscopic traffic flow models for the application to online traffic control systems by applying the dynamic flow-density relation. The new modelling approach alleviates a critical problem, i.e. the parameter calibration problem, of existing traffic flow models. (orig.)

  13. Applications and perspectives of multi-parameter flow cytometry to microbial biofuels production processes.

    Science.gov (United States)

    da Silva, Teresa Lopes; Roseiro, José Carlos; Reis, Alberto

    2012-04-01

    Conventional microbiology methods used to monitor microbial biofuels production are based on off-line analyses. The analyses are, unfortunately, insufficient for bioprocess optimization. Real time process control strategies, such as flow cytometry (FC), can be used to monitor bioprocess development (at-line) by providing single cell information that improves process model formulation and validation. This paper reviews the current uses and potential applications of FC in biodiesel, bioethanol, biomethane, biohydrogen and fuel cell processes. By highlighting the inherent accuracy and robustness of the technique for a range of biofuel processing parameters, more robust monitoring and control may be implemented to enhance process efficiency. PMID:22257766

  14. Laser Doppler Blood Flow Imaging Using a CMOS Imaging Sensor with On-Chip Signal Processing

    Directory of Open Access Journals (Sweden)

    Cally Gill

    2013-09-01

    Full Text Available The first fully integrated 2D CMOS imaging sensor with on-chip signal processing for applications in laser Doppler blood flow (LDBF imaging has been designed and tested. To obtain a space efficient design over 64 × 64 pixels means that standard processing electronics used off-chip cannot be implemented. Therefore the analog signal processing at each pixel is a tailored design for LDBF signals with balanced optimization for signal-to-noise ratio and silicon area. This custom made sensor offers key advantages over conventional sensors, viz. the analog signal processing at the pixel level carries out signal normalization; the AC amplification in combination with an anti-aliasing filter allows analog-to-digital conversion with a low number of bits; low resource implementation of the digital processor enables on-chip processing and the data bottleneck that exists between the detector and processing electronics has been overcome. The sensor demonstrates good agreement with simulation at each design stage. The measured optical performance of the sensor is demonstrated using modulated light signals and in vivo blood flow experiments. Images showing blood flow changes with arterial occlusion and an inflammatory response to a histamine skin-prick demonstrate that the sensor array is capable of detecting blood flow signals from tissue.

  15. Laser doppler blood flow imaging using a CMOS imaging sensor with on-chip signal processing.

    Science.gov (United States)

    He, Diwei; Nguyen, Hoang C; Hayes-Gill, Barrie R; Zhu, Yiqun; Crowe, John A; Gill, Cally; Clough, Geraldine F; Morgan, Stephen P

    2013-01-01

    The first fully integrated 2D CMOS imaging sensor with on-chip signal processing for applications in laser Doppler blood flow (LDBF) imaging has been designed and tested. To obtain a space efficient design over 64 × 64 pixels means that standard processing electronics used off-chip cannot be implemented. Therefore the analog signal processing at each pixel is a tailored design for LDBF signals with balanced optimization for signal-to-noise ratio and silicon area. This custom made sensor offers key advantages over conventional sensors, viz. the analog signal processing at the pixel level carries out signal normalization; the AC amplification in combination with an anti-aliasing filter allows analog-to-digital conversion with a low number of bits; low resource implementation of the digital processor enables on-chip processing and the data bottleneck that exists between the detector and processing electronics has been overcome. The sensor demonstrates good agreement with simulation at each design stage. The measured optical performance of the sensor is demonstrated using modulated light signals and in vivo blood flow experiments. Images showing blood flow changes with arterial occlusion and an inflammatory response to a histamine skin-prick demonstrate that the sensor array is capable of detecting blood flow signals from tissue. PMID:24051525

  16. Disconnected quark diagram in decays of psi

    International Nuclear Information System (INIS)

    Based on the quartet model, three body decays psi(psi')?VPP and rho'?rho?? are analysed. It is shown that the decay widths can be explained by taking into consideration of the disconnected quark diagram whose coupling have SU(3) and SU(4) breaking pattern like in Pomeron exchange processes. (auth.)

  17. Parallel Computation of Feynman diagrams with DIANA

    OpenAIRE

    Tentyukov, M.; Fleischer, J.

    2003-01-01

    Co-operation of the Feynman DIagram ANAlyzer (DIANA) with the underlying operational system (UNIX) is presented. We discuss operators to run external commands and a recent development of parallel processing facilities and an extension in the spirit of a component model.

  18. On the application of kinematic models and diffusive processes for debris flows.

    Science.gov (United States)

    Arattano, M.; Franzi, L.

    2009-04-01

    Debris flows generally propagate along mountain torrents characterized by very steep slopes. Thus the dynamics of debris flows are primarily governed by gravitational and frictional forces, which are related to the channel slope and to the friction slope respectively. On the contrary, on milder slopes, also the forces originating along the flow-depth gradient can play an important role, as well as the inertial forces. The modelling of debris flows occurring on steep slopes is thus generally conducted by means of the application of the so-called kinematic model, which takes into account only the effects of slope and friction and neglect all the remaining terms. The application of kinematic models describes fairly well the experimental and field evidences of the propagation of debris flows along torrents, particularly the changes in space and time of discharge and flow stage. Notwithstanding some questions may arise. These latter regard a) the diffusion processes that take place in debris flows: these cannot be theoretically predicted by kinematic models, since diffusion is a second-order process b) the influence of numerical diffusion on integration. In other words, theoretically speaking, the one-to-one relationship between discharge and stage, a key trait of the kinamatic wave, imposes a significant physical and mathematical constraint, that is the absence of dissipation. This is not generally shown by the application of numerical models to debris flows, even when the solution is analytically obtained. In the paper a discussion of these aspects is made, by referring also to the debates on the same subject arisen for flood waves. An application of a generalized diffusion wave model and of a kinematic model is proposed for a debris flow occurred in Rio Moscardo (Italy) and recorded by some ultrasonic sensors. The results show the limitations of the applied models, whose application is discussed by means of the calculation of dimensionless parameters proposed in literature.

  19. The GC computer code for flow sheet simulation of pyrochemical processing of spent nuclear fuels

    International Nuclear Information System (INIS)

    The GC computer code has been developed for flow sheet simulation of pyrochemical processing of spent nuclear fuel. It utilizes a robust algorithm SLG for analyzing simultaneous chemical reactions between species distributed across many phases. Models have been developed for analysis of the oxide fuel reduction process, salt recovery by electrochemical decomposition of lithium oxide, uranium separation from the reduced fuel by electrorefining, and extraction of fission products into liquid cadmium. The versatility of GC is demonstrated by applying the code to a flow sheet of current interest

  20. Non-static flow processes in pipelines for liquids and gases

    International Nuclear Information System (INIS)

    Non-static flow processes do not necessarily lead to critical conditions of the pipeline, the pipeline supports and the connected components. Criteria for assessing them are additional stresses in the pipeline caused by shock loads or vibration, and the loads aon pipelin supports and connecting components. The type of superimposition of this additional stress on top of the loads existing in cold or warm operational pipelines and the determination of the safety factors for dimensioning components depend on whether the existing flow processes are classified as operating or fault cases. (orig.)

  1. PROBLEMS AND TERMS OF THE IMPLEMENTATION OF OPTIMAL FLOW PROCESSES MANAGEMENT

    Directory of Open Access Journals (Sweden)

    I. Dzobko

    2012-06-01

    Full Text Available The relevance of the logistics concept concerning the solution of flow processes optimal control problems of industrial enterprises is discussed in the article. Modern tools of logistics make it possible to resolve the existing contradictions in Ukrainian economy by unifying business-structures into a single efficient system.While dealing with enterprise optimal management as a total combination of flow processes, logistics plays the main role as a regulator between an enterprise and resources market on the one hand, and an enterprise and sales market of finished goods on the other hand. Thus, there is a constant exchange (supply of matter, energy and information between the links of a continuous chain (supply chain.Such a definition as "variability" is suggested as a fundamental reason of inconsistency. The concept of variability is explained as any deviation at input / output processes from the desired ideal values. From this points of view the fundamental way to improve system efficiency is to reduce this variability.The current management of an enterprise should take into consideration integration and innovation aspects of economy. It should be based on consistency and compliance of flow processes of an enterprise, and be predictive. The conditions for implementation of optimal (logistics management of flow processes were outlined.

  2. Conservative generalized bifurcation diagrams

    International Nuclear Information System (INIS)

    Bifurcation cascades in conservative systems are shown to exhibit a generalized diagram, which contains all relevant informations regarding the location of periodic orbits (resonances), their width (island size), irrational tori and the infinite higher-order resonances, showing the intricate way they are born. Contraction rates for islands sizes, along period-doubling bifurcations, are estimated to be ?I?3.9. Results are demonstrated for the standard map and for the continuous Hénon–Heiles potential. The methods used here are very suitable to find periodic orbits in conservative systems, and to characterize the regular, mixed or chaotic dynamics as the nonlinear parameter is varied.

  3. Using Eye Tracking to Investigate Semantic and Spatial Representations of Scientific Diagrams During Text-Diagram Integration

    Science.gov (United States)

    Jian, Yu-Cin; Wu, Chao-Jung

    2015-02-01

    We investigated strategies used by readers when reading a science article with a diagram and assessed whether semantic and spatial representations were constructed while reading the diagram. Seventy-one undergraduate participants read a scientific article while tracking their eye movements and then completed a reading comprehension test. Our results showed that the text-diagram referencing strategy was commonly used. However, some readers adopted other reading strategies, such as reading the diagram or text first. We found all readers who had referred to the diagram spent roughly the same amount of time reading and performed equally well. However, some participants who ignored the diagram performed more poorly on questions that tested understanding of basic facts. This result indicates that dual coding theory may be a possible theory to explain the phenomenon. Eye movement patterns indicated that at least some readers had extracted semantic information of the scientific terms when first looking at the diagram. Readers who read the scientific terms on the diagram first tended to spend less time looking at the same terms in the text, which they read after. Besides, presented clear diagrams can help readers process both semantic and spatial information, thereby facilitating an overall understanding of the article. In addition, although text-first and diagram-first readers spent similar total reading time on the text and diagram parts of the article, respectively, text-first readers had significantly less number of saccades of text and diagram than diagram-first readers. This result might be explained as text-directed reading.

  4. Towards an optimized flow-sheet for a SANEX demonstration process using centrifugal contactors

    International Nuclear Information System (INIS)

    The design of an efficient process flow-sheet requires accurate extraction data for the experimental set-up used. Often this data is provided as equilibrium data. Due to the small hold-up volume compared to the flow rate in centrifugal contactors the time for extraction is often too short to reach equilibrium D-ratios. In this work single stage kinetics experiments have been carried out to investigate the D-ratio dependence of the flow rate and to compare this with equilibrium batch experiments for a SANEX system based on CyMe4-BTBP. The first centrifuge experiment was run with spiked solutions while in the second a genuine actinide/lanthanide fraction from a TODGA process was used. Three different flow rates were tested with each set-up. The results show that even with low flow rates, only around 9% of the equilibrium D-ratio (Am) was reached for the extraction in the spiked test and around 16% in the hot test (the difference is due to the size of the centrifuges). In the hot test the lanthanide scrubbing was inefficient whereas in the stripping both the actinides and the lanthanides showed good results. Based on these results improvements of the suggested flow-sheet is discussed. (orig.)

  5. Modeling studies for multiphase fluid and heat flow processes in nuclear waste isolation

    International Nuclear Information System (INIS)

    Multiphase fluid and heat flow plays an important role in many problems relating to the disposal of nuclear wastes in geologic media. Examples include boiling and condensation processes near heat-generating wastes, flow of water and formation gas in partially saturated formations, evolution of a free gas phase from waste package corrosion in initially water-saturated environments, and redistribution (dissolution, transport, and precipitation) of rock minerals in non-isothermal flow fields. Such processes may strongly impact upon waste package and repository design considerations and performance. This paper summarizes important physical phenomena occurring in multiphase and nonisothermal flows, as well as techniques for their mathematical modeling and numerical simulation. Illustrative applications are given for a number of specific fluid and heat flow problems, including: thermohydrologic conditions near heat-generating waste packages in the unsaturated zone; repository-wide convection effects in the unsaturated zone; effects of quartz dissolution and precipitation for disposal in the saturated zone; and gas pressurization and flow corrosion of low-level waste packages. 34 refs; 7 figs; 2 tabs

  6. Modeling Unsaturated Flow and Transport Processes in Fractured Tuffs of Yucca Mountain

    International Nuclear Information System (INIS)

    This paper presents a field modeling study characterizing fluid flow and tracer transport in the unsaturated zone of Yucca Mountain, Nevada, a proposed underground repository for storing high-level radioactive waste. The 500 to 700 meter thick unsaturated zone of Yucca Mountain consists of highly heterogeneous layers of anisotropic, fractured ash flow and air fall tuffs. Characterization of fluid flow and heat transfer through such a system has been a challenge due to the heterogeneities prevalent on various scales. Quantitative evaluation of water, gas, and heat flow by means of numerical simulation is essential for design and performance assessment of the repository. A three-dimensional numerical flow and transport model will be discussed. The model has been calibrated against field-measured data and takes into account the coupled processes of unsaturated flow and tracer transport in the highly heterogeneous, unsaturated fractured porous rock. The modeling approach of the model is based on a dual-continuum formulation of coupled multiphase fluid and tracer transport through fractured porous rock. As application examples, effects of current and future climates on the unsaturated zone processes are evaluated to aid in the assessment of the proposed repository's system performance

  7. Study of an ammonia-based wet scrubbing process in a continuous flow system

    Energy Technology Data Exchange (ETDEWEB)

    Mao, James X.; Lee, Anita S.; Kitchin, John R.; Nulwala, Hunaid B.; Luebke, David R.; Damodaran, Krishnan

    2013-01-01

    A continuous gas and liquid flow, regenerative scrubbing process for CO{sub 2} capture was demonstrated at the bench-scale level. An aqueous ammonia-based solution captures CO{sub 2} from simulated flue gas in an absorber and releases a nearly pure stream of CO{sub 2} in the regenerator. After the regeneration, the solution of ammonium compounds is recycled to the absorber. The design of a continuous flow unit was based on earlier exploratory results from a semi-batch reactor, where a CO{sub 2} and N{sub 2} simulated flue gas mixture flowed through a well-mixed batch of ammonia-based solution. During the semi-batch tests, the solution was cycled between absorption and regeneration steps to measure the carrying capacity of the solution at various initial ammonia concentrations and temperatures. Consequentially, a series of tests were conducted on the continuous unit to observe the effect of various parameters on CO{sub 2} removal efficiency and regenerator effectiveness within the flow system. The parameters that were studied included absorber temperature, regenerator temperature, initial NH{sub 3} concentration, simulated flue gas flow rate, liquid solvent inventory in the flow system, and height of the packed-bed absorber. From this testing and subsequent testing, ammonia losses from both the absorption and regeneration steps were quantified, and attempts were made to maintain steady state during operations. Implications of experimental results with respect to process design are discussed.

  8. Hybrid modeling of convective laminar flow in a permeable tube associated with the cross-flow process

    Science.gov (United States)

    Venezuela, A. L.; Pérez-Guerrero, J. S.; Fontes, S. R.

    2009-03-01

    The confined flows in tubes with permeable surfaces are associated to tangential filtration processes (microfiltration or ultrafiltration). The complexity of the phenomena do not allow for the development of exact analytical solutions, however, approximate solutions are of great interest for the calculation of the transmembrane outflow and estimate of the concentration polarization phenomenon. In the present work, the generalized integral transform technique (GITT) was employed in solving the laminar and permanent flow in permeable tubes of Newtonian and incompressible fluid. The mathematical formulation employed the parabolic differential equation of chemical species conservation (convective-diffusive equation). The velocity profiles for the entrance region flow, which are found in the connective terms of the equation, were assessed by solutions obtained from literature. The velocity at the permeable wall was considered uniform, with the concentration at the tube wall regarded as variable with an axial position. A computational methodology using global error control was applied to determine the concentration in the wall and concentration boundary layer thickness. The results obtained for the local transmembrane flux and the concentration boundary layer thickness were compared against others in literature.

  9. Geo-Hydro Statistical Characterization of Preferential Flow and Transport Processes in Karst Groundwater Systems

    Science.gov (United States)

    Anaya, A. A.; Padilla, I. Y.; Macchiavelli, R. E.

    2011-12-01

    Karst groundwater systems are highly productive and provide an important fresh water resource for human development and ecological integrity. Their high productivity is often associated with conduit flow and high matrix permeability. The same characteristics that make these aquifers productive also make them highly vulnerable to contamination and a likely for contaminant exposure. Of particular interest are chlorinated organic contaminants and phthalates derived from industrial solvents and plastic by-products. These chemicals have been identified as potential precursors of pre-term birth, a leading cause of neonatal complications with a significant health and societal cost. The general objectives of this work are to: (1) develop fundamental knowledge and determine the processes controlling the release, mobility, persistence, and possible pathways of contaminants in karst groundwater systems, and (2) characterize transport processes in conduit and diffusion-dominated flow under base flow and storm flow conditions. The work presented herein focuses on the development of geo-hydro statistical tools to characterize flow and transport processes under different flow regimes. Multidimensional, laboratory-scale Geo-Hydrobed models were developed and tested for this purpose. The models consist of stainless-steel tanks containing karstified limestone blocks collected from the karst aquifer formation of northern Puerto Rico. The models a network of sampling wells to monitor flow, pressure, and solute concentrations temporally and spatially. Experimental work entailed making a series of point injections in wells while monitoring the hydraulic response in other wells. Statistical mixed models were applied to spatial probabilities of hydraulic response and weighted injected volume data, and were used to determinate the best spatial correlation structure to represent paths of preferential flow in the limestone units under different groundwater flow regimes. Preliminary testing of the karstified models show that the system can be used to represent the variable transport regime characterized by conduit and diffuses flow in the karst systems. Initial hydraulic characterization indicates a highly heterogeneous system resulting in large preferential flow components. Future works involve characterization of dual porosity system using conservative tracers, fate and transport experiments using phthalates and chlorinated solvents, geo-temporal statistical modeling, and the testing of "green" remediation technologies in karst groundwater. This work is supported by the U.S. Department of Energy, Savannah River (Grant Award No. DE-FG09-07SR22571), and the National Institute of Environmental Health Sciences (NIEHS, Grant Award No. P42ES017198).

  10. Extended sequence diagram for human system interaction

    International Nuclear Information System (INIS)

    Unified Modeling Language (UML) is a modeling language in the field of object oriented software engineering. The sequence diagram is a kind of interaction diagram that shows how processes operate with one another and in what order. It is a construct of a message sequence chart. It depicts the objects and classes involved in the scenario and the sequence of messages exchanged between the objects needed to carry out the functionality of the scenario. This paper proposes the Extended Sequence Diagram (ESD), which is capable of depicting human system interaction for nuclear power plants, as well as cognitive process of operators analysis. In the conventional sequence diagram, there is a limit to only identify the activities of human and systems interactions. The ESD is extended to describe operators' cognitive process in more detail. The ESD is expected to be used as a task analysis method for describing human system interaction. The ESD can also present key steps causing abnormal operations or failures and diverse human errors based on cognitive condition

  11. Extended sequence diagram for human system interaction

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Jong Rok; Choi, Sun Woo; Ko, Hee Ran; Kim, Jong Hyun [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2012-10-15

    Unified Modeling Language (UML) is a modeling language in the field of object oriented software engineering. The sequence diagram is a kind of interaction diagram that shows how processes operate with one another and in what order. It is a construct of a message sequence chart. It depicts the objects and classes involved in the scenario and the sequence of messages exchanged between the objects needed to carry out the functionality of the scenario. This paper proposes the Extended Sequence Diagram (ESD), which is capable of depicting human system interaction for nuclear power plants, as well as cognitive process of operators analysis. In the conventional sequence diagram, there is a limit to only identify the activities of human and systems interactions. The ESD is extended to describe operators' cognitive process in more detail. The ESD is expected to be used as a task analysis method for describing human system interaction. The ESD can also present key steps causing abnormal operations or failures and diverse human errors based on cognitive condition.

  12. Numerical Analysis of the Molten Steel Flow Consider Solidification at the Continuous Casting Process

    International Nuclear Information System (INIS)

    Continuous casting process is widely used for making mid stage of manufactured steel product. Characteristics of steel flow in the mold is very important for mold design and SEN(Submerged Entry Nozzle) and using CFD analysis, numerical approach to molten steel flow can be very useful in understanding its flow characteristics in the mold and also make us easily understand growing of solidification shell thickness near mold wall. This study was done for predicting solidification shell thickness in the beam blank model for continuous casting of steel, using commercial FVM Cartesian Solver, STREAM V6. For considering turbulent flow, the low Reynolds number ?-? model was used. Solidification of molten steel is calculated through the temperature recovery method. And this solidification model was also applied to benchmark cases for validating with experimental and numerical results of other researchers

  13. Aerodynamic study on supersonic flows in high-velocity oxy-fuel thermal spray process

    Science.gov (United States)

    Katanoda, Hiroshi; Matsuoka, Takeshi; Kuroda, Seiji; Kawakita, Jin; Fukanuma, Hirotaka; Matsuo, Kazuyasu

    2005-06-01

    To clarify the characteristics of gas flow in high velocity oxy-fuel (HVOF) thermal spray gun, aerodynamic research is performed using a special gun. The gun has rectangular cross-sectional area and sidewalls of optical glass to visualize the internal flow. The gun consists of a supersonic nozzle with the design Mach number of 2.0 followed by a straight passage called barrel. Compressed dry air up to 0.78 MPa is used as a process gas instead of combustion gas which is used in a commercial HVOF gun. The high-speed gas flows with shock waves in the gun and jets are visualized by schlieren technique. Complicated internal and external flow-fields containing various types of shock wave as well as expansion wave are visualized.

  14. Turbulence and Fluid Flow: Perspectives. Physical Processes in Terrestrial and Aquatic Ecosystems, Transport Processes.

    Science.gov (United States)

    Simpson, James R.

    This module is part of a series on Physical Processes in Terrestrial and Aquatic Ecosystems. The materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process

  15. Supporting UML Sequence Diagrams with a Processor Net Approach

    Directory of Open Access Journals (Sweden)

    Tony Spiteri Staines

    2007-08-01

    Full Text Available UML sequence diagrams focus on the interaction between different classes. For distributed real time transaction processing it is possible to end up with complex sequence diagrams, containing messages related to system processes. It is difficult to examine alternative combinations of message passing. A solution is to translate these diagrams into an executable processor net model. This is based on the ‘actor model’, Petri net concepts and higher order net constructs. A case study taken from a flight reservation scenario is introduced and used to create a processor net model. This approach offers various advantages like identifying the main processes, executable model creation, verification, formalization, defining schemas and performance analysis.

  16. Synthesis of elementary thermodynamic processes in nonequilibrium two-phase flow without slip

    Energy Technology Data Exchange (ETDEWEB)

    Stosic, Z. (Siemens AG Unternehmensbereich KWU, Erlangen (Germany, F.R.)); Ninic, N. (Institut za Nuklearne Nauke Boris Kidric, Belgrade (Yugoslavia))

    1990-10-01

    A new procedure is developed for analyzing adiabatic and diabatic flow of a two-phase fluid with subcooled and saturated boiling. The method is based on decomposition of complex and simultaneous processes into elementary ones, while the change of state is determined by the thermodynamically based summation of elementary processes. Compared to other developed methods, the advantage of the method presented here is its simple calculation procedure, without iteration and problems connected to stability and convergence. (orig.).

  17. Parallelized CCHE2D flow model with CUDA Fortran on Graphics Process Units

    Science.gov (United States)

    This paper presents the CCHE2D implicit flow model parallelized using CUDA Fortran programming technique on Graphics Processing Units (GPUs). A parallelized implicit Alternating Direction Implicit (ADI) solver using Parallel Cyclic Reduction (PCR) algorithm on GPU is developed and tested. This solve...

  18. Sediment transfer processes in a debris-flow dominated catchment in the Swiss Alps

    Science.gov (United States)

    McArdell, B. W.; Berger, C.; Schlunegger, F.

    2009-12-01

    The transfer of sediment from steep hillslopes into channels and subsequent mobilization remains a problem with implications for the development of landscapes as well as applications in natural hazards mitigation. The Illgraben catchment in the Swiss Alps is among the most active catchments in Europe, with several 100’000 cubic meters of sediment exported from the catchment (active area front velocity (max. 10 m/s) and front flow depth (max. 3.25 m) as well as estimates for debris flow volume (max. 85,000 cubic meters). Flow bulk density data are also available from a large force plate installation for most flows since 2004, permitting estimation of sediment export from the catchment by debris flows. The channel morphology is strongly affected by these events, and debris flows can increase their volume considerably by entraining material from the channel bed. Aerial photography of the initiation area and upper catchment (fall 2007, early summer and fall 2008; fall 2009 is planned) and photogrammetric analyses allow detection of areas of land surface elevation change (deposition or erosion). Strong hillslope channel coupling is expected, with sediment delivery to the steep torrent channels by rockfall and other mass-movement processes. The upper catchment is generally quite active, yet the main sediment source of debris flows varies from event to event In some cases it was possible to identify the movement of small landslides into torrent channels and the subsequent removal by debris flows. In other cases no landslide activity was obvious and the sediment for the debris flows probably originated from the sediments stored within the channels.

  19. FPGA Implementations of Ladder Diagrams

    Directory of Open Access Journals (Sweden)

    Neil William Bergmann

    2013-02-01

    Full Text Available The performance of programmable logic controllers is often constrained by the microprocessor and the real-time firmware of the controller. Field programmable gate arrays (FPGAs are an attractive potential implementation medium for high-speed control because of their fast and parallel execution and programmable nature. Ladder Diagrams are a standard graphical programming method for industrial controllers, but compilers from Ladder Diagrams to FPGA hardware do not yet exist. This paper explores the comparative speed of four different classes of FGPA implementation of Ladder Diagrams - Interpreted Software, Compiled Software, Interpreted Hardware and Compiled Hardware. It also explores parallel versus serial execution of Ladder Diagrams in hardware, and identifies timers as a major resource user in parallel implementations. Overall, a Shared Timer Serial Compiled Hardware system for FPGA implementation of Ladder Diagrams is recommended. Using comparable FPGA resources to other alternatives it provides a 20-600 times speed improvement over other solutions whilst maintaining correct Ladder Diagram semantics.

  20. Great Plains Gasification Project process stream design data. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Honea, F.I.

    1985-09-01

    The Great Plains Coal Gasification Plant (GPGP) in the first commercial coal-to-SNG synthetic fuel plant constructed and operated in the United States. This process stream design data report provides non-proprietary information to the public on the major GPGP process streams. The report includes a simplified plant process block flow diagram, process input/output diagrams and stream design data sheets for 161 major GPGP process and effluent streams. This stream design data provides an important base for evaluation of plant and process performance and for verification of the DOE ASPEN computer simulation models of the GPGP processes. 8 refs.

  1. A pseudo-haptic knot diagram interface

    Science.gov (United States)

    Zhang, Hui; Weng, Jianguang; Hanson, Andrew J.

    2011-01-01

    To make progress in understanding knot theory, we will need to interact with the projected representations of mathematical knots which are of course continuous in 3D but significantly interrupted in the projective images. One way to achieve such a goal would be to design an interactive system that allows us to sketch 2D knot diagrams by taking advantage of a collision-sensing controller and explore their underlying smooth structures through a continuous motion. Recent advances of interaction techniques have been made that allow progress to be made in this direction. Pseudo-haptics that simulates haptic effects using pure visual feedback can be used to develop such an interactive system. This paper outlines one such pseudo-haptic knot diagram interface. Our interface derives from the familiar pencil-and-paper process of drawing 2D knot diagrams and provides haptic-like sensations to facilitate the creation and exploration of knot diagrams. A centerpiece of the interaction model simulates a "physically" reactive mouse cursor, which is exploited to resolve the apparent conflict between the continuous structure of the actual smooth knot and the visual discontinuities in the knot diagram representation. Another value in exploiting pseudo-haptics is that an acceleration (or deceleration) of the mouse cursor (or surface locator) can be used to indicate the slope of the curve (or surface) of whom the projective image is being explored. By exploiting these additional visual cues, we proceed to a full-featured extension to a pseudo-haptic 4D visualization system that simulates the continuous navigation on 4D objects and allows us to sense the bumps and holes in the fourth dimension. Preliminary tests of the software show that main features of the interface overcome some expected perceptual limitations in our interaction with 2D knot diagrams of 3D knots and 3D projective images of 4D mathematical objects.

  2. Integrating turbulent flow, biogeochemical, and poromechanical processes in rippled coastal sediment (Invited)

    Science.gov (United States)

    Cardenas, M. B.; Cook, P. L.; Jiang, H.; Traykovski, P.

    2010-12-01

    Coastal sediments are the locus of multiple coupled processes. Turbulent flow associated with waves and currents induces porewater flow through sediment leading to fluid exchange with the water column. This porewater flow is determined by the hydraulic and elastic properties of the sediment. Porewater flow also ultimately controls biogeochemical reactions in the sediment whose rates depend on delivery of reactants and export of products. We present results from numerical modeling studies directed at integrating these processes with the goal of shedding light on these complex environments. We show how denitrification rates inside ripples are largest at intermediate permeability which represents the optimal balance of reactant delivery and anoxic conditions. It is clear that nutrient cycling and distribution within the sediment is strongly dependent on the character of the multidimensional flow field inside of sediment. More recent studies illustrate the importance of the elastic properties of the saturated sediment on modulating fluid exchange between the water column and the sediment when pressure fluctuations along the sediment-water interface occur at the millisecond scale. Pressure fluctuations occur at this temporal scale due to turbulence and associated shedding of vortices due to the ripple geometry. This suggests that biogeochemical cycling may also be affected by these high-frequency elastic effects. Future studies should be directed towards this and should take advantage of modeling tools such as those we present.

  3. Developing the technique of image processing for the study of bubble dynamics in subcooled flow boiling

    International Nuclear Information System (INIS)

    This study presents the development of an image processing technique for studying the dynamics behaviors of vapor bubbles in a two-phase bubbly flow. It focuses on the quantitative assessment of some basic parameters such as a local bubble size and size distribution in the range of void fraction between 0.03 < a < 0.07. The image processing methodology is based upon the computer evaluation of high speed motion pictures obtained from the flow field in the region of underdeveloped subcooled flow boiling for a variety of experimental conditions. This technique has the advantage of providing computer measurements and extracting the bubbles of the two-phase bubbly flow. This method appears to be promising for determining the governing mechanisms in subcooled flow boiling, particularly near the point of net vapor generation. The data collected by the image analysis software can be incorporated into the new models and computer codes currently under development, which are aimed at incorporating the effect of vapor generation and condensation separately. (Original)

  4. A multi-component two-phase flow algorithm for use in landfill processes modelling.

    Science.gov (United States)

    White, J K; Nayagum, D; Beaven, R P

    2014-09-01

    This paper describes the finite difference algorithm that has been developed for the flow sub-model of the University of Southampton landfill degradation and transport model LDAT. The liquid and gas phase flow components are first decoupled from the solid phase of the full multi-phase, multi-component landfill process constitutive equations and are then rearranged into a format that can be applied as a calculation procedure within the framework of a three dimensional array of finite difference rectangular elements. The algorithm contains a source term which accommodates the non-flow landfill processes of degradation, gas solubility, and leachate chemical equilibrium, sub-models that have been described in White and Beaven (2013). The paper includes an illustration of the application of the flow sub-model in the context of the leachate recirculation tests carried out at the Beddington landfill project. This illustration demonstrates the ability of the sub-model to track movement in the gas phase as well as the liquid phase, and to simulate multi-directional flow patterns that are different in each of the phases. PMID:24925875

  5. Application of machine learning and expert systems to Statistical Process Control (SPC) chart interpretation

    Science.gov (United States)

    Shewhart, Mark

    1991-01-01

    Statistical Process Control (SPC) charts are one of several tools used in quality control. Other tools include flow charts, histograms, cause and effect diagrams, check sheets, Pareto diagrams, graphs, and scatter diagrams. A control chart is simply a graph which indicates process variation over time. The purpose of drawing a control chart is to detect any changes in the process signalled by abnormal points or patterns on the graph. The Artificial Intelligence Support Center (AISC) of the Acquisition Logistics Division has developed a hybrid machine learning expert system prototype which automates the process of constructing and interpreting control charts.

  6. An experimental study of fluvial processes at asymmetrical river confluences with hyperconcentrated tributary flows

    Science.gov (United States)

    Zhang, Yuanfeng; Wang, Ping; Wu, Baosheng; Hou, Suzhen

    2015-02-01

    This paper reports findings from experimental studies of sediment transport and bed morphology at asymmetrical confluences with hyperconcentrated tributary flows in the upper Yellow River. The results indicate that the hyperconcentrated flow confluence can be divided into four hydraulic regions, including the backwater zone above the upstream junction corner, the maximum velocity area, the separation flow zone, and the post-confluence region downstream of the junction corner. The bed morphology also consists of four basic elements, including the sandbar in the backwater zone, the bar in the separation flow zone, the thalweg for flow conveyance and sediment transport, and bars in the reach downstream of the separation zone. The sediment load of the hyperconcentrated flow from the tributary was the most important control on fluvial processes at such confluences. The increase in deposition in the backwater zone as the sediment load increased was almost linear, and the depth of sediment deposition in the backwater zone was approximately normal in distribution. The validity of a conceptual model for discriminating the status of the backwater effect, developed earlier from field data using the relationship between the sediment load and water volume of hyperconcentrated flows, was confirmed by the experiments. Deposition in the reach downstream of the junction, sandbar height in the backwater zone, and the width and length of the separation zone bar all tended to increase as the sediment load in the tributary increased. An obvious upstream-directed density current occurred in the backwater zone when the sediment concentration of the hyperconcentrated flow exceeded a critical value. The travel distance of the density current increased as the sediment load in the tributary increased. A formula was proposed, based on sediment continuity, for estimating the deposition volume in the reach downstream of the junction. Compared with ordinary sediment-laden flow confluences, hyperconcentrated flow confluences have a sandbar in the backwater zone associated with an upstream-directed density current that may sometimes block the main channel. Hyperconcentrated flow confluences have a thalweg, and so are different from debris flow confluences, which have a fan-shaped deposit.

  7. Recleaning of HEPA filters by reverse flow - evaluation of the underlying processes and the cleaning technique

    International Nuclear Information System (INIS)

    HEPA filter operation at high concentrations of fine dusts requires the periodic recleaning of the filter units in their service locations. Due to the low mechanical stress induced during the recleaning process the regenration via low pressure reverse flow is a very suitable technique. Recleanability of HEPA filter had been attained for particle diameter >0,4 ?m at air velocities up to 1 m/s, but filter clogging occurred in case of smaller particles. The recleaning forces are too weak for particles <0,4 ?m. With respect to the low tensile strength of HEPA filter media higher flow velocities are excluded. The analysis of reverse flow recleaning in a single pleat device showed extremly non uniform flow pattern in conventional deep-pleat pack geometries. More uniform flow conditions are attained by changing the pleat geometry. The realisation of high flow velocities at the glas fiber medium inside the filter pack requires shortening of the pleates to some 150 mm and the adaptation of the distance between filter pack and the recleaning device with respect to the nozzle diameter and the width of the filter pleats. (orig.). 44 figs., 36 refs

  8. Magnetic phase diagram of dysprosium

    International Nuclear Information System (INIS)

    We have studied the magnetic phase diagram of single crystal dysprosium (Dy) below the Neel temperature. The recent study by Andrianov et al. showed that magnetic phase diagram of Dy for applied magnetic field along the b-axis, contains four regions: I - helical antiferromagnetic phase, II - angular phase, III - fan phase and IV - collinear ferromagnetic phase. In our study we have used magnetization measurements to construct the magnetic phase diagram of Dy in the H-T plane (H is the applied magnetic field, T is the temperature). Our magnetic phase diagram of Dy for H along the b-axis is very similar to that of Andrianov et al. (orig.)

  9. A Signal Pre-processing Algorithm Applied for Ultrasonic Flow-Meter

    Directory of Open Access Journals (Sweden)

    Rang-ding Wang

    2013-09-01

    Full Text Available In order to solve the problem of time difference ultrasonic flow meter’s low accuracy, against the basic characteristics of the sample data, a data-processing algorithm is proposed. First, we use shell sort do a data pre-processing to the samples, then remove the error of the sample space by complex digital filter, and use the error compensation algorithm to get the final sample results. Among them, the complex digital filter is mainly composed by median filtering algorithm, sliding window, Peters algorithm and the weighted average algorithm. This kind of data processing algorithm can effectively filter out the error of the sample space. It can also make a large improvement to the accuracy of ultrasonic flow meter while ensure the stability and real-time.

  10. Evaluation of alternative flow sheets for upgrade of the Process Waste Treatment Plant

    International Nuclear Information System (INIS)

    Improved chemical precipitation and/or ion-exchange (IX) methods are being developed at the Oak Ridge National Laboratory (ORNL) in an effort to reduce waste generation at the Process Waste Treatment Plant (PWTP). A wide variety of screening tests were performed on potential precipitation techniques and IX materials on a laboratory scale. Two of the more promising flow sheets have been tested on pilot and full scales. The data were modeled to determine the operating conditions and waste generation at plant-scale and used to develop potential flow sheets for use at the PWTP. Each flow sheet was evaluated using future-valve economic analysis and performance ratings (where numerical values were assigned to costs, process flexibility and simplicity, stage of development, waste reduction, environmental and occupational safety, post-processing requirements, and final waste form). The results of this study indicated that several potential flow sheets should be considered for further development, and more detailed cost estimates should be made before a final selection is made for upgrade of the PWTP. 19 refs., 52 figs., 22 tabs

  11. Transactions on Computational Science IX : Special Issue on Voronoi Diagrams in Science and Engineering

    DEFF Research Database (Denmark)

    2011-01-01

    The 9th issue of the Transactions on Computational Science journal, edited by François Anton, is devoted to the subject of Voronoi diagrams in science and engineering. The 9 papers included in the issue constitute extended versions of selected papers from the International Symposium on Voronoi Diagrams, held in Copenhagen, Denmark, June 23-36, 2009. Topics covered include: divide and conquer construction of Voronoi diagrams; new generalized Voronoi diagrams or properties of existing generalized Voronoi diagrams; and applications of Voronoi diagrams and their duals in graph theory, computer graphics, bioinformatics, and spatial process simulation.

  12. A Semi-Markov Process based Optimization Method for Availability of Hybrid Flow Shop

    Directory of Open Access Journals (Sweden)

    Fei Simiao

    2013-01-01

    Full Text Available As Hybrid Flow Shops (HFS are common manufacturing environments, availability of HFS is a basic indicator for measuring usage ability. Optimal maintenance strategy which achieves maximum availability with cost constraints, provides a better platform for its scheduling problems. We propose an availability model in this study by using Semi-Markov Process (SMP under a general maintenance strategy which suit for general distribution of machines’ life time distribution and maintenance time distribution. Based on the availability model, the maintenance site configuration optimization method is with total cost constrains. Furthermore, the method is applied to a simple hybrid flow shop and showed to be effective.

  13. Whiteness process of tile ceramics: using a synthetic flow as a modifier agent of color firing

    Science.gov (United States)

    dos Santos, G. R.; Pereira, M. C.; Olzon-Dionysio, M.; de Souza, S. D.; Morelli, M. R.

    2014-01-01

    Synthetic flow is proposed as a modifier agent of color firing in tile ceramic mass during the sinterization process, turning the red color firing into whiteness. Therefore, the 57Fe Mössbauer spectroscopy was used to understand how the interaction of the iron element in the mechanism of color firing mass occurs in this system. The results suggest that the change of color firing can be alternatively due to two main factors: (i) diluting the hematite content in the sample because of the use of synthetic flow and (ii) part of the hematite is converted in other uncolored crystal structures, which makes the final color firing lighter.

  14. POWER FLOW ANALYSIS OF A CONTINUOUS PROCESS PLANT: (A CASE STUDY

    Directory of Open Access Journals (Sweden)

    SMITA ACHARYA, PRAGATI GUPTA, M.A.MUJAWAR

    2013-06-01

    Full Text Available For the continuous evaluation of the performance of the power system, power flow solutions are essential for exhibiting suitable control actions in case of requirement. This case study presents analysis of the electrical power system of continuous process plant having its own captive generation along with the provision of the Grid connectivity. The different power system elements are modeled as per the manufacturer’s data sheet. To evaluate the steady state performance, power flow simulations and analysis of the complex power system for various invasive operating conditions are carried out.

  15. Self-sustained processes in the logarithmic layer of turbulent channel flows

    Science.gov (United States)

    Hwang, Yongyun; Cossu, Carlo

    2011-06-01

    It has recently been shown that large-scale and very-large-scale motions can self-sustain in turbulent channel flows even in the absence of input from motions at smaller scales. Here we show that also motions at intermediate scales, mainly located in the logarithmic layer, survive when motions at smaller scales are artificially quenched. These elementary self-sustained motions involve the bursting and regeneration of sinuous streaks. This is a further indication that a full range of autonomous self-sustained processes exists in turbulent channel flows with scales ranging from those of the buffer layer streaks to those of the large scale motions in the outer layer.

  16. Gas flow through a multilayer ceramic mould in lost wax foundry process

    Directory of Open Access Journals (Sweden)

    H. Matysiak

    2009-04-01

    Full Text Available The paper deals with the issues of permeability testing of ceramic moulds used in lost wax foundry process. The main issue in thetesting is to provide proper specimens of ceramic moulds (CM. The moulds have to be repeatable and must be free of internal defects ofmicrocrack type that are formed mainly during the removal of patterns from CM in the course of heat treatment.Moreover, the process of forming ceramic moulds must be similar to the general industrial process of CM moulds making regardingtheir anisotropic structure. The permeability parameter reflecting gas flow through multilayer ceramic moulds was also examined withattention to the investment casting shape accuracy.

  17. Numerical Study on Steel Flow and Inclusion Behavior during a Ladle Teeming Process

    OpenAIRE

    Ni, Peiyuan

    2013-01-01

    Inclusions in molten steel have received worldwide concern due to their serious influence on both the steel product quality and the steel production process. These inclusions may come from the deoxidation process, reoxidation by air and/or slag due to an entrainment during steel transfer, and so on. They can break up a casting process by clogging a nozzle. A good knowledge on both steel flow and inclusion behavior is really important to understand nozzle clogging, as well as to take some poss...

  18. Assessing winter storm flow generation by means of permeability of the lithology and hydrological soil processes

    Directory of Open Access Journals (Sweden)

    H. Hellebrand

    2007-06-01

    Full Text Available In this study two approaches are used to predict winter storm flow coefficients in meso-scale basins (10 km2 to 1000 km2 with a view to regionalization. The winter storm flow coefficient corresponds to the ratio between rainfall and direct discharge caused by this rainfall. It is basin specific and supposed to give an integrated response to rainfall. The two approaches, which used the permeability of the substratum and soil hydrological processes as basin attributes are compared. The study area is the Rhineland Palatinate and the Grand Duchy of Luxembourg and the study focuses on the Nahe basin and its 16 sub-basins (Rhineland Palatinate. For the comparison, three statistical models were derived by means of regression analysis. The models used the winter storm flow coefficient as the dependent variable in the models; the independent variables were the permeability of the substratum, preliminary derived hydrological soil processes and a combination of both. It is assumed that the permeability and the preliminary derived hydrological soil processes carry different layers of information. Cross-validation and a statistical test were used to determine and evaluate model differences. The cross-validation resulted in a best model performance for the model that used both parameters, followed by the model that used the preliminary hydrological soil processes. From the statistical test it was concluded that the models come from different populations, carrying different information layers. Analysis of the residuals of the models indicated that the permeability and hydrological soil processes did provide complementary information. Simple linear models appeared to perform well in describing the winter storm flow coefficient at the meso-scale when a combination of the permeability of the substratum and soil hydrological processes served as independent parameters.

  19. Benchmark initiative on coupled multiphase flow and geomechanical processes during CO2 injection

    Science.gov (United States)

    Benisch, K.; Annewandter, R.; Olden, P.; Mackay, E.; Bauer, S.; Geiger, S.

    2012-12-01

    CO2 injection into deep saline aquifers involves multiple strongly interacting processes such as multiphase flow and geomechanical deformation, which threat to the seal integrity of CO2 repositories. Coupled simulation codes are required to establish realistic prognoses of the coupled process during CO2 injection operations. International benchmark initiatives help to evaluate, to compare and to validate coupled simulation results. However, there is no published code comparison study so far focusing on the impact of coupled multiphase flow and geomechanics on the long-term integrity of repositories, which is required to obtain confidence in the predictive capabilities of reservoir simulators. We address this gap by proposing a benchmark study. A wide participation from academic and industrial institutions is sought, as the aim of building confidence in coupled simulators become more plausible with many participants. Most published benchmark studies on coupled multiphase flow and geomechanical processes have been performed within the field of nuclear waste disposal (e.g. the DECOVALEX project), using single-phase formulation only. As regards CO2 injection scenarios, international benchmark studies have been published comparing isothermal and non-isothermal multiphase flow processes such as the code intercomparison by LBNL, the Stuttgart Benchmark study, the CLEAN benchmark approach and other initiatives. Recently, several codes have been developed or extended to simulate the coupling of hydraulic and geomechanical processes (OpenGeoSys, ELIPSE-Visage, GEM, DuMuX and others), which now enables a comprehensive code comparison. We propose four benchmark tests of increasing complexity, addressing the coupling between multiphase flow and geomechanical processes during CO2 injection. In the first case, a horizontal non-faulted 2D model consisting of one reservoir and one cap rock is considered, focusing on stress and strain regime changes in the storage formation and the cap rock. For the second case, a fault is introduced to investigate the risk of fault reactivation and fracturing due to CO2 injection for a single and a multiple cap rock system, respectively. A multiple injector setting exposed to different tectonic stress regimes is proposed for the third case. Hereby, a 3D model is used compartmentalized by low permeability faults, which become permeable due to injection. Injection scenarios will be evaluated for extensional and compressive stress regimes. All model set-ups are based on already published simulation results of coupled multiphase flow and geomechanical processes during CO2 injection. To end with, a real site geometry including parameterization and realistic reservoir conditions is provided. The benchmark design and cases will be presented as well as some preliminary simulation results for the first cases. Interested institutions and researchers are invited to discuss and to participate in the study.

  20. The Cerebral Blood Flow Correlates of Emotional Facial Processing in Mild Alzheimer's Disease

    Directory of Open Access Journals (Sweden)

    Lawrence J. Whalley

    2011-03-01

    Full Text Available Deficits in facial emotion processing are features of mild Alzheimer’s disease (AD. These impairments are often dis-tressing for carers as well as patients. Such non-cognitive symptoms are often cited as a contributing reason for admis-sion into institutionalised care. The ability to interpret emotional cues is crucial to healthy psychological function and relationships and impaired emotional facility may lead to antisocial behavior. Understanding the origins of the non-cognitive aspects of AD may lead to an improvement in the management of sufferers and ease the carer burden. In a cross-sectional study we recorded patients’ facial processing abilities, (emotion and identity recognition and disease severity (ADAS-cog, Neuropsychiatic Inventory and investigated the regional cerebral blood flow correlates of facial emotion processing deficits using 99Tcm HMAPO rCBF SPECT. Using statistical parametric mapping (SPM we iden-tified decreased blood flow in posterior frontal regions specifically associated with emotion perception deficits. Non-emotional facial processing abilities or disease severity. The posterior frontal lobe has been identified in previous stud-ies in the absence of dementia as being important in emotion processing. The results suggest that the cognitive disease severity, in combination with the facial processing ability, do not completely explain facial emotion processing in AD patients and that the posterior frontal lobe mediates such behaviour.

  1. GDS-based Mask Data Preparation Flow: Data Volume Containment by Hierarchical Data Processing

    Science.gov (United States)

    Schulze, Steffen F.; LaCour, Pat; Buck, Peter D.

    2002-12-01

    As the industry enters the development of the 65nm node the pressure on the data path and tapeout flow is growing. Design complexity and increased deployment of resolution enhancement techniques (RET) result in rapidly growing file sizes, which turns what used to be the relatively simple task of mask data preparation into a real bottleneck. This discussion introduces the data preparation scheme in the mask house and analyzes its evolution. Mask data preparation (MDP) has evolved from a flow that only needed to support a single mask lithography tool data format (MEBES) with minimal data alteration steps to one which requires the support of many mask lithography tool data formats and at the same time requires significant data alteration to support the increased precision necessary for today"s advanced masks.. However, the MDP flow developed around the MEBES format and it"s derivatives still exists. The design community has migrated towards the use of hierarchical data formats and processes to control file size and processing time. MDP, which from a file size and process complexity point of view is beginning to look more and more like the advanced RET operations performed on the data prior to mask manufacturing, is still standardized on a flat data format that is poorly optimized for a growing number of mask lithography tools. Based on examples it will be shown how this complicates the data handling further. An alternate data preparation flow accommodating the larger files and re-gaining flexibility for turnaround time (TAT) and throughput management is suggested. This flow utilizes the hierarchical GDS-II format as the exchange format for mask data preparation. It complements the existing flow for the most complex designs. The introduction of a hierarchical exchange format enables the transfer of a number of necessary data preparation steps into the hierarchical domain. Data processing strategies are discussed. The paper illustrates the benefit of hierarchical processing based on GDS-II files with experimental data on file size reduction and TAT improvement for direct format conversions vs. re-fracturing as well as other processing steps. The implications for the established data preparation approaches and potential alternatives for the communication between the mask manufacturer and the customer will be discussed. The potential for further enhancements by converting to a hierarchical format that has a more efficient data representation than the commonly used GDS-II format will be discussed and illustrated.

  2. A Temperature-Profile Method for Estimating Flow Processes in Geologic Heat Pipes

    International Nuclear Information System (INIS)

    Above-boiling temperature conditions, as encountered, for example, in geothermal reservoirs and in geologic repositories for the storage of heat-producing nuclear wastes, may give rise to strongly altered liquid and gas flow processes in porous subsurface environments. The magnitude of such flow perturbation is extremely hard to measure in the field. We therefore propose a simple temperature-profile method that uses high-resolution temperature data for deriving such information. The energy that is transmitted with the vapor and water flow creates a nearly isothermal zone maintained at about the boiling temperature, referred to as a heat pipe. Characteristic features of measured temperature profiles, such as the differences in the gradients inside and outside of the heat pipe regions, are used to derive the approximate magnitude of the liquid and gas fluxes in the subsurface, for both steady-state and transient conditions

  3. A Temperature-Profile Method for Estimating Flow Processes inGeologic Heat Pipes

    Energy Technology Data Exchange (ETDEWEB)

    Birkholzer, Jens T.

    2004-12-06

    Above-boiling temperature conditions, as encountered, forexample, in geothermal reservoirs and in geologic repositories for thestorage of heat-producing nuclear wastes, may give rise to stronglyaltered liquid and gas flow processes in porous subsurface environments.The magnitude of such flow perturbation is extremely hard to measure inthe field. We therefore propose a simple temperature-profile method thatuses high-resolution temperature data for deriving such information. Theenergy that is transmitted with the vapor and water flow creates a nearlyisothermal zone maintained at about the boiling temperature, referred toas a heat pipe. Characteristic features of measured temperature profiles,such as the differences in the gradients inside and outside of the heatpipe regions, are used to derive the approximate magnitude of the liquidand gas fluxes in the subsurface, for both steady-state and transientconditions.

  4. Experimental determination of the flow capacity coefficient for control valves of process

    Scientific Electronic Library Online (English)

    G., Aragón-Camarasa; G., Aragón-González; A., Canales-Palma; A., León-Galicia.

    2009-01-01

    Full Text Available A test bench was conceived in order to determine experimentally the flow coefficient [C V] for process control valves, operating with compressible fluids, under established regulations by the standards ANSI/ISA-75.02-1996 and ANSI/ISA-75.01.01-2002. This test bench is used to verify the calibration [...] of valves with continually variable opening, after they have been repaired. The measurements in the test bench allow establishing the C V of these valves for various opening percentages. It was necessary to go through the C V equation for compressible fluids, to proceed with the flow sensor selection. This equation was obtained under similarity conditions by the equality of Euler numbers between prototype and model (test specimen). It is also described the electronic instrumentation for measuring flow, temperature and pressure difference, the design and the development of electronic circuits which control the instrumentation, and the algorithms for the operation and acquisition of measurements.

  5. Signal processing and statistical descriptive reanalysis of steady state chute-flow experiments

    Science.gov (United States)

    truong, hoan; eckert, nicolas; keylock, chris; naaim, mohamed; bellot, hervé

    2014-05-01

    An accurate knowledge of snow rheology is needed for the mitigation against avalanche hazard. Indeed snow avalanches have a significant impact on the livelihoods and economies of alpine communities. To do so, 60 small-scale in-situ flow experiments were performed with various slopes, temperatures and flow depths. The investigation of these data previously seemed to show the dense flow of dry snow may be composed of two layers; a sheared basal layer made of single snow grains and a less sheared upper layer made of large aggregates. These outcomes were mainly based on the mean velocity profile of the flow and on interpretation in terms of rheological behavior of granular materials and snow microstructure [Pierre G. Rognon et al., 2007]. Here, the main objective remains the same, but the rheological and physical viewpoints are put aside to extract as much information contained in the data as possible various using signal processing methods and descriptive statistics methods as the maximum overlap discrete wavelet transform (MODWT), transfer entropy (TE) and maximum cross-correlation (MCC). Specifically, we aim at the improving the velocity estimations as function of the depth particularly the velocity fluctuations around the mean profile to better document the behavior of dense dry snow flows during a steady and uniform chute regime. The data are composed of pairs of voltage signals (right and left), which makes that the velocity is known indirectly only. The MCC method is classically used to determine the time lag between both signals. Previously, the MCC method that showed the mean velocity profile may be fitted by a simple bilinear function [Pierre G. Rognon et al., 2007], but no interesting temporal dynamics could be highlighted. Hence, a new process method was developed to provide velocity series with much better temporal resolution. The process is mainly made of a MODWT-based denoising method and the choice of window size for correlation. The results prove to be good enough in term of reasonable variability and measurement numbers. A statistical descriptive analysis of the velocity results shows a disagreement with the previous outcomes. Indeed, the clustering method and the empirical probability distribution functions show that the vertical velocity profile may reflect three different behaviors, possibly corresponding to three layers and/or to transient flow layers. These flow layers are located at different heights depending on initial conditions of flow experiments (temperature, slope and depth). Keywords: Maximum cross correlation, MODWT, probability distribution function

  6. Developing a method for digital image processing of two phase fluid flows

    International Nuclear Information System (INIS)

    A new image processing technique was developed in the current study to understand the effects of various hydrodynamics and geometric parameters on local phase distribution phenomena in non-equilibrium two-phase flow systems. While image processing has been employed extensively in velocimetry, its application to explain the two-phase flow phenomena is new. The present study consisted of developing the technique and using it to extract phase distribution data. This, technique presents an advantage of providing measurements and extracting the bubbles of the two-phase bubbly flow compared with the traditionally used methods: point by point measurement technique or digitization. The image processing method proposed in this study is based on the detachment and tracing of the edges of the bubbles and their background. The conclusions are summarized below. (i) High speed photographic results show different behaviors of the bubbles. Some bubbles slide along the wall and detach by rapid ejection into the flow. The motion of these bubbles into the liquid core cause a violent agitation of the liquid near the heated surface. It was also noted that some bubbles detach the surface and sweep downstream and recondensing slowly in the bulk flow. This difference in bubble behavior indicates that the ejection mechanism is influenced by hydrodynamics or thermal condition and will be of interest for further study. (ii) Vapor bubble departure diameters in forced convection subcooled boilingers in forced convection subcooled boiling, have been experimentally obtained over a range of mass flux, D, and heat flux, qw, for the subcooled flow boiling region. (iii) For the flow conditions experimentally investigated, the overwhelming majority of the bubbles leave the nucleation sites by sliding a finite distance along the heating surface lifting off the wall. The results can be utilized in explaining the mechanism of subcooled nucleate flow boiling especially in determining the dynamics of the local void distribution and void behavior, particularly, near the point of net vapor generation. The values of the bubble size and shape, interfacial area, information about void formation. bubble growth or collapse and its size and position as well as the velocity of the bubbles for particular conditions, are also evaluated. (Original)

  7. Calculation of metallurgical phase diagrams

    International Nuclear Information System (INIS)

    Developments in the thermochemical calculation of metallurgical phase diagrams for the beginning of the century up to the present are briefly summarized. More recent examples of calculated phase equilibria in different types of binary, ternary and higher-order system are described and the advantages of such calculations over conventional phase diagram determinations are discussed. (orig.)

  8. Perturbations to the Hubble diagram

    OpenAIRE

    Schucker, Thomas; Zouzou, Ilhem

    2005-01-01

    We compute the linear responses of the Hubble diagram to small scalar perturbations in the Robertson-Walker metric and to small peculiar velocities of emitter and receiver. We discuss the monotonicity constraint of the Hubble diagram in the light of these responses.

  9. The Mathematical Model of the Coal Gasification Process in a Flow

    Directory of Open Access Journals (Sweden)

    Nikolai Nikolaevich Efimov

    2014-11-01

    Full Text Available The work purpose - perfection of gasification technologies of processing low reactive high zole coals. For purpose achievement the method of an intensification of process of gasification of coal in an ascending stream of the oxidizer activated by nanocatalyst, and also a mathematical model of the specified process is offered. A mathematical model of a process of coal gasification in a one-dimensional steady flow in the form of a system of ordinary differential equations of energy and changes in the concentrations of the reactants is represented in this paper. Model is based on the kinetics of chemical reactions that determine the process. The offered mathematical model will allow to make calculations of parameters of macrokinetics and heat exchange at coal gasification in an ascending stream.

  10. Research on fracture analysis, groundwater flow and sorption processes in fractured rocks

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dae-Ha; Kim, Won-Young; Lee, Seung-Gu [Korea Institute of Geology Mining and Materials, Taejon (KR)] (and others)

    1999-12-01

    Due to increasing demand for numerous industrial facilities including nuclear power plants and waste repositories, the feasibility of rocks masses as sites for the facilities has been a geological issue of concern. Rock masses, in general, comprises systems of fractures which can provide pathways for groundwater flow and may also affect the stability of engineered structures. For the study of groundwater flow and sorption processes in fractured rocks, five boreholes were drilled. A stepwise and careful integration of various data obtained from field works and laboratory experiments were carried out to analyze groundwater flow in fractured rocks as follows; (1) investigation of geological feature of the site, (2) identification and characterization of fracture systems using core and televiewer logs, (3) determination of hydrogeological properties of fractured aquifers using geophysical borehole logging, pumping and slug tests, and continuous monitoring of groundwater level and quality, (4) evaluation of groundwater flow patterns using fluid flow modeling. The results obtained from these processes allow a qualitative interpretation of fractured aquifers in the study area. Column experiments of some reactive radionuclides were also performed to examine sorption processes of the radionuclides including retardation coefficients. In addition, analyses of fracture systems covered (1) reconstruction of the Cenozoic tectonic movements and estimation of frequency indices for the Holocene tectonic movements, (2) determination of distributions and block movements of the Quaternary marine terraces, (3) investigation of lithologic and geotechnical nature of study area, and (4) examination of the Cenozoic volcanic activities and determination of age of the dike swarms. Using data obtained from above mentioned analyses along with data related to earthquakes and active faults, probabilistic approach was performed to determine various potential hazards which may result from the Quaternary or the Holocene tectonic movements. (author). 223 refs., 55 tabs., 144 figs.

  11. Research on fracture analysis, groundwater flow and sorption processes in fractured rocks

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dae Ha [Korea Institute of Geology Mining and Materials, Taejon (Korea)

    1998-12-01

    Due to increasing demand for numerous industrial facilities including nuclear power plants and waste repositories, the feasibility of rocks masses as sites for the facilities has been a geological issue of concern. Rock masses, in general, comprises systems of fractures which can provide pathways for groundwater flow and may also affect the stability of engineered structures. such properties of fractures stimulate a synthetic study on (1) analyses of fracture systems, and (2) characterization of groundwater flow and sorption processes in fractured rocks to establish a preliminary model for assessing suitable sites for industrial facilities. The analyses of fracture systems cover (1) reconstruction of the Cenozoic tectonic movements and estimation of frequency indices for the Holocene tectonic movements, (2) determination of distributions and block movements of the Quaternary marine terraces, (3) investigation of lithologic and geotechnical nature of study area, and (4) examination of the Cenozoic volcanic activities and determination of age of the dike swarms. Using data obtained from above mentioned analyses along with data related to earthquakes and active faults, probabilistic approach is performed to determine various potential hazards which may result from the Quaternary or the Holocene tectonic movements. In addition, stepwise and careful integration of various data obtained from field works and laboratory experiments are carried out to analyze groundwater flow in fractures rocks as follows; (1) investigation of geological feature of the site, (2) identification and characterization of fracture systems using core and televiewer logs, (3) determination of conductive fractures using electrical conductivity, temperature, and flow logs, (4) identification of hydraulic connections between fractures using televiewer logs with tracer tests within specific zones. The results obtained from these processes allow a qualitative interpretation of groundwater flow patterns in the study area. Column experiments of some reactive radionuclides are also performed to examine sorption processes of the radionuclides including retardation coefficients. (author). 118 refs., 18 tabs., 35 figs.

  12. Effect of inlet and outlet flow conditions on natural gas parameters in supersonic separation process.

    Science.gov (United States)

    Yang, Yan; Wen, Chuang; Wang, Shuli; Feng, Yuqing

    2014-01-01

    A supersonic separator has been introduced to remove water vapour from natural gas. The mechanisms of the upstream and downstream influences are not well understood for various flow conditions from the wellhead and the back pipelines. We used a computational model to investigate the effect of the inlet and outlet flow conditions on the supersonic separation process. We found that the shock wave was sensitive to the inlet or back pressure compared to the inlet temperature. The shock position shifted forward with a higher inlet or back pressure. It indicated that an increasing inlet pressure declined the pressure recovery capacity. Furthermore, the shock wave moved out of the diffuser when the ratio of the back pressure to the inlet one was greater than 0.75, in which the state of the low pressure and temperature was destroyed, resulting in the re-evaporation of the condensed liquids. Natural gas would be the subsonic flows in the whole supersonic separator, if the mass flow rate was less than the design value, and it could not reach the low pressure and temperature for the condensation and separation of the water vapor. These results suggested a guidance mechanism for natural gas supersonic separation in various flow conditions. PMID:25338207

  13. Hyperbolic Voronoi diagrams made easy

    CERN Document Server

    Nielsen, Frank

    2009-01-01

    We present a simple framework to compute hyperbolic Voronoi diagrams of finite point sets as affine diagrams. We prove that bisectors in Klein's non-conformal disk model are hyperplanes that can be interpreted as power bisectors of Euclidean balls. Therefore our method simply consists in computing an equivalent clipped power diagram followed by a mapping transformation depending on the selected representation of the hyperbolic space (e.g., Poincar\\'e conformal disk or upper-plane representations). We discuss on extensions of this approach to weighted and $k$-order diagrams, and describe their dual triangulations. Finally, we consider two useful primitives on the hyperbolic Voronoi diagrams for designing tailored user interfaces of an image catalog browsing application in the hyperbolic disk: (1) finding nearest neighbors, and (2) computing smallest enclosing balls.

  14. Incorporating atmospheric boundary layer processes in an integrated surface/subsurface flow and transport model

    Science.gov (United States)

    Davison, J. H.; Hwang, H.; Sudicky, E. A.; Lin, J. C.

    2012-12-01

    Traditional land surface-atmosphere models idealize variably-saturated subsurface flow by parameterizing the non-linear processes. Many previous models reduce the subsurface systems to either one-dimensional infiltration or constant-value boundary conditions. Consequently, the shortfalls of the currently available models constrain our ability to estimate the role of a spatially and temporally dynamic subsurface flow on atmospheric processes. In order to overcome these limitations, we developed a coupled atmospheric boundary layer model, which is a zero-dimensional energy balance model, with HydroGeoSphere, a three-dimensional integrated surface/variably-saturated subsurface flow and energy transport model. The atmospheric boundary layer model calculates the net radiation, air temperature, moisture content, and precipitation in the atmosphere and relays the information directly to HydroGeoSphere to compute the water flow, land surface and subsurface temperatures, and evapotranspiration. As an illustration, the coupled model is applied to land-use change in a Mediterranean climate transitioning from irrigated agriculture to urban communities to evaluate the variation in latent and sensible heat fluxes. Finally, our model's performance and results are compared to those of the traditional land surface models.

  15. Batch-processed carbon nanotube wall as pressure and flow sensor

    International Nuclear Information System (INIS)

    A pressure and flow sensor based on the electrothermal-thermistor effect of a batch-processed carbon nanotube wall (CNT wall) is presented. The negative temperature coefficient of resistance (TCR) of CNTs and the temperature dependent tunneling rate through the CNT/silicon junction enable vacuum pressure and flow velocity sensing because the heat transfer rate between CNTs and the surrounding gas molecules differs depending on pressure and flow rate. The CNT walls are synthesized by thermal chemical vapor deposition (CVD) on an array of microelectrodes fabricated on a silicon-on-insulator (SOI) wafer. The CNTs are self-assembled between the microelectrodes and substrate across the thickness of a buried oxide layer during the synthesis process, and the simple batch fabrication results in high throughput and yield. A wide pressure range, down to 3 x 10-3 from 105 Pa, and a nitrogen flow velocity range between 1 and 52.4 mm s-1, are sensed. Further experimental characterizations of the bias voltage dependent response of the sensor as a vacuum pressure gauge are presented.

  16. Batch-processed carbon nanotube wall as pressure and flow sensor

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jungwook; Kim, Jongbaeg, E-mail: kimjb@yonsei.ac.kr [School of Mechanical Engineering, Yonsei University, 262 Seongsanno, Seodaemun-gu, Seoul 120-749 (Korea, Republic of)

    2010-03-12

    A pressure and flow sensor based on the electrothermal-thermistor effect of a batch-processed carbon nanotube wall (CNT wall) is presented. The negative temperature coefficient of resistance (TCR) of CNTs and the temperature dependent tunneling rate through the CNT/silicon junction enable vacuum pressure and flow velocity sensing because the heat transfer rate between CNTs and the surrounding gas molecules differs depending on pressure and flow rate. The CNT walls are synthesized by thermal chemical vapor deposition (CVD) on an array of microelectrodes fabricated on a silicon-on-insulator (SOI) wafer. The CNTs are self-assembled between the microelectrodes and substrate across the thickness of a buried oxide layer during the synthesis process, and the simple batch fabrication results in high throughput and yield. A wide pressure range, down to 3 x 10{sup -3} from 10{sup 5} Pa, and a nitrogen flow velocity range between 1 and 52.4 mm s{sup -1}, are sensed. Further experimental characterizations of the bias voltage dependent response of the sensor as a vacuum pressure gauge are presented.

  17. Metal flow of a tailor-welded blank in deep drawing process

    Science.gov (United States)

    Yan, Qi; Guo, Ruiquan

    2005-01-01

    Tailor welded blanks were used in the automotive industry to consolidate parts, reduce weight, and increase safety. In recent years, this technology was developing rapidly in China. In Chinese car models, tailor welded blanks had been applied in a lot of automobile parts such as rail, door inner, bumper, floor panel, etc. Concerns on the properties of tailor welded blanks had become more and more important for automobile industry. A lot of research had shown that the strength of the welded seam was higher than that of the base metal, such that the weld failure in the aspect of strength was not a critical issue. However, formability of tailor welded blanks in the stamping process was complex. Among them, the metal flow of tailor welded blanks in the stamping process must be investigated thoroughly in order to reduce the scrap rate during the stamping process in automobile factories. In this paper, the behavior of metal flow for tailor welded blanks made by the laser welding process with two types of different thickness combinations were studied in the deep drawing process. Simulations and experiment verification of the movement of weld line for tailor welded blanks were discussed in detail. Results showed that the control on the movement of welded seam during stamping process by taking some measures in the aspect of blank holder was effective.

  18. Toward a Grid Work flow Formal Composition

    International Nuclear Information System (INIS)

    This paper exposes a new approach for the composition of grid work flow models. This approach proposes an abstract syntax for the UML Activity Diagrams (UML-AD) and a formal foundation for grid work flow composition in form of a work flow algebra based on UML-AD. This composition fulfils the need for collaborative model development particularly the specification and the reduction of the complexity of grid work flow model verification. This complexity has arisen with the increase in scale of grid work flow applications such as science and e-business applications since large amounts of computational resources are required and multiple parties could be involved in the development process and in the use of grid work flows. Furthermore, the proposed algebra allows the definition of work flow views which are useful to limit the access to predefined users in order to ensure the security of grid work flow applications. (Author)

  19. Investigation of Multiscale and Multiphase Flow, Transport and Reaction in Heavy Oil Recovery Processes; SEMIANNUAL

    International Nuclear Information System (INIS)

    The emphasis of this work was on investigating the mechanisms and factors that control the recovery of heavy oil with the objective to improve recovery efficiencies. For this purpose the interaction of flow transport and reaction at various scales from the pore network to the field scales were studied. Particular mechanisms to be investigated included the onset of gas flow in foamy oil production and in in-situ steam drive, gravity drainage in steam processes, the development of sustained combustion fronts and the propagation of foams in porous media. Analytical, computational and experimental methods were utilized to advance the state of the art in heavy oil recovery. Successful completion of this research was expected to lead to improvements in the Recovery efficiency of various heavy oil processes

  20. Three-dimensional particle tracking velocimetry measurement for bubbly flow with digital color image processing

    International Nuclear Information System (INIS)

    In this paper we present the study on a three-dimensional PTV (particle tracking velocimetry) measurement of bubbly flow with color digital image processing. The tracers for the liquid motions shine with yellow-green by an ultra-violet illumination. The bubbles are shadow of the incandescent lights with red-colored cellophane sheets. By using six mirrors we lead the image of the test section seen from different three directions to a high-speed color video camera. Color digital image processing makes the bubbles and tracers extracted from background light. We calculate the velocity vectors, trajectories and the three-dimensional characteristics of the bubbles. We reconstruct the whole bubbly flow and present one by OpenGL. (author)

  1. The low moisture eastern coal processing system at the UTSI-DOE Coal Fired Flow Facility

    Energy Technology Data Exchange (ETDEWEB)

    Evans, B.R.; Washington, E.S.; Sanders, M.E.

    1993-10-01

    A low moisture, eastern coal processing system was constructed at the Department of Energy`s Coal Fired Flow Facility (CFFF), located at the University of Tennessee Space Institute in Tullahoma, Tennessee, to provide a metered and regulated supply of seeded, pulverized coal to support magnetohydrodynamic (MHD) power generation research. The original system configuration is described as well as major modifications made in response to specific operational problems. Notable among these was the in-house development of the Moulder flow control valve which exhibited marked improvement in durability compared to previous valves used with pulverized coal. Coal processing system performance parameters are discussed. A summary of tests conducted and significant events are included.

  2. Calibration in process monitoring by using unsegmented continuous-flow systems

    OpenAIRE

    Castro, M. D. Luque; Valca?rcel, M.

    1989-01-01

    An overview is presented of the different aspects of the role of analytical chemistry in process monitoring and control. On-line monitoring is currently the most attractive option in this area, especially with unsegmented-flow techniques. In addition to allowing automation of these systems, the variety of ways in which calibration and recalibration can be performed allows their adaptation to any situation by using extremely simple, home-made manifolds. The most relevant d...

  3. A realization of an automated data flow for data collecting, processing, storing and retrieving

    International Nuclear Information System (INIS)

    GEONET is a database system developed at the Stanford Linear Accelerator Center for the alignment of the Stanford Linear Collider. It features an automated data flow, ranging from data collection using HP110 handheld computers to processing, storing and retrieving data and finally to adjusted coordinates. This paper gives a brief introduction to the SLC project and the applied survey methods. It emphasizes the hardware and software implementation of GEONET using a network of IBM PC/XT's. 14 refs., 4 figs

  4. Octopaminergic modulation of temporal frequency coding in an identified optic flow-processing interneuron

    Directory of Open Access Journals (Sweden)

    KitD.Longden

    2010-11-01

    Full Text Available Flying generates predictably different patterns of optic flow compared with other locomotor states. A sensorimotor system tuned to rapid responses and a high bandwidth of optic flow would help the animal to avoid wasting energy through imprecise motor action. However, neural processing that covers a higher input bandwidth itself comes at higher energetic costs which would be a poor investment when the animal was not flying. How does the blowfly adjust the dynamic range of its optic flow-processing neurons to the locomotor state? Octopamine (OA is a biogenic amine central to the initiation and maintenance of flight in insects. We used an OA agonist chlordimeform (CDM to simulate the widespread OA release during flight and recorded the effects on the temporal frequency coding of the H2 cell. This cell is a visual interneuron known to be involved in flight stabilization reflexes. The application of CDM resulted in i an increase in the cell's spontaneous activity, expanding the inhibitory signalling range ii an initial response gain to moving gratings (20 – 60 ms post-stimulus that depended on the temporal frequency of the grating and iii a reduction in the rate and magnitude of motion adaptation that was also temporal frequency-dependent. To our knowledge, this is the first demonstration that the application of a neuromodulator can induce velocity-dependent alterations in the gain of a wide-field optic flow-processing neuron. The observed changes in the cell’s response properties resulted in a 33% increase of the cell’s information rate when encoding random changes in temporal frequency of the stimulus. The increased signalling range and more rapid, longer lasting responses employed more spikes to encode each bit, and so consumed a greater amount of energy. It appears that for the fly investing more energy in sensory processing during flight is more efficient than wasting energy on under-performing motor control.

  5. Opportunities in IT Support of Workflow & Information Flow in the Emergency Department Digital Imaging Process

    OpenAIRE

    Fairbanks, Rj; Guarrera, Tk; Bisantz, Ab; Venturino, M.; Westesson, Pl

    2010-01-01

    The goal of this study is to examine workflow and information flow in the emergency department (ED) digital imaging process to identify features of an optimized system. Radiological imaging (x-rays, CT scans, etc) is unique in the ED setting, as the need for fast turn-around time and interactive communication between radiologists and emergency physicians is different than that of most other healthcare settings. The information technology systems which are used by both radiologists and emergen...

  6. Material processing of convection-driven flow field and temperature distribution under oblique gravity

    Science.gov (United States)

    Hung, R. J.

    1995-01-01

    A set of mathematical formulation is adopted to study vapor deposition from source materials driven by heat transfer process under normal and oblique directions of gravitational acceleration with extremely low pressure environment of 10(exp -2) mm Hg. A series of time animation of the initiation and development of flow and temperature profiles during the course of vapor deposition has been obtained through the numerical computation. Computations show that the process of vapor deposition has been accomplished by the transfer of vapor through a fairly complicated flow pattern of recirculation under normal direction gravitational acceleration. It is obvious that there is no way to produce a homogeneous thin crystalline films with fine grains under such a complicated flow pattern of recirculation with a non-uniform temperature distribution under normal direction gravitational acceleration. There is no vapor deposition due to a stably stratified medium without convection for reverse normal direction gravitational acceleration. Vapor deposition under oblique direction gravitational acceleration introduces a reduced gravitational acceleration in vertical direction which is favorable to produce a homogeneous thin crystalline films. However, oblique direction gravitational acceleration also induces an unfavorable gravitational acceleration along horizontal direction which is responsible to initiate a complicated flow pattern of recirculation. In other words, it is necessary to carry out vapor deposition under a reduced gravity in the future space shuttle experiments with extremely low pressure environment to process vapor deposition with a homogeneous crystalline films with fine grains. Fluid mechanics simulation can be used as a tool to suggest most optimistic way of experiment with best setup to achieve the goal of processing best nonlinear optical materials.

  7. - GEONET - A Realization of an Automated Data Flow for Data Collecting, Processing, Storing, and Retrieving

    Energy Technology Data Exchange (ETDEWEB)

    Friedsam, Horst; Pushor, Robert; Ruland, Robert; /SLAC

    2005-08-12

    GEONET is a database system developed at the Stanford Linear Accelerator Center for the alignment of the Stanford Linear Collider. It features an automated data flow, ranging from data collection using HP110 handheld computers to processing, storing and retrieving data and finally to adjusted coordinates. This paper gives a brief introduction to the SLC project and the applied survey methods. It emphasizes the hardware and software implementation of GEONET using a network of IBM PC/XT's.

  8. Design of a Single-Cell Positioning Controller Using Electroosmotic Flow and Image Processing

    OpenAIRE

    Jhong-Yin Chen; Chao-Wang Young; Chyung Ay

    2013-01-01

    The objective of the current research was not only to provide a fast and automatic positioning platform for single cells, but also improved biomolecular manipulation techniques. In this study, an automatic platform for cell positioning using electroosmotic flow and image processing technology was designed. The platform was developed using a PCI image acquisition interface card for capturing images from a microscope and then transferring them to a computer using human-machine interface softwar...

  9. Magma flow, exsolution processes and rock metasomatism in the Great Messejana–Plasencia dyke (Iberian Peninsula)

    OpenAIRE

    Silva, Pedro F.; Henry, Bernard; Marques, Fernando Ornelas; Font, Eric; Mateus, Anto?nio; Vegas, Ramo?n; Miranda, Jorge Miguel; Palomino, Ricardo; Palencia Ortas, Alicia

    2008-01-01

    Magma flow in dykes is still not well understood; some reported magnetic fabrics are contradictory and the potential effects of exsolution and metasomatism processes on the magnetic properties are issues open to debate. Therefore, a long dyke made of segments with different thickness, which record distinct degrees of metasomatism, the Messejana–Plasencia dyke (MPD), was studied. Oriented dolerite samples were collected along several cross-sections and characterized by means o...

  10. Do students use and understand free-body diagrams?

    Directory of Open Access Journals (Sweden)

    David Rosengrant

    2009-06-01

    Full Text Available Physics education literature recommends using multiple representations to help students understand concepts and solve problems. However, there is little research concerning why students use the representations and whether those who use them are more successful. This study addresses these questions using free-body diagrams (diagrammatic representations used in problems involving forces as a type of representation. We conducted a two-year quantitative and qualitative study of students’ use of free-body diagrams while solving physics problems. We found that when students are in a course that consistently emphasizes the use of free-body diagrams, the majority of them do use diagrams on their own to help solve exam problems even when they receive no credit for drawing the diagrams. We also found that students who draw diagrams correctly are significantly more successful in obtaining the right answer for the problem. Lastly, we interviewed students to uncover their reasons for using free-body diagrams. We found that high achieving students used the diagrams to help solve the problems and as a tool to evaluate their work while low achieving students only used representations as aids in the problem-solving process.

  11. Great Plains Gasification Project process stream design data. [Lurgi Process

    Energy Technology Data Exchange (ETDEWEB)

    Honea, F.I.

    1985-09-01

    The Great Plains Coal Gasification Plant (GPGP) is the first commercial coal-to-synthetic natural gas plant constructed and operated in the United States. This process stream design data report provides non-proprietary information to the public on the major GPGP process streams. The report includes a simplified plant process block flow diagram, process input/output diagrams, and stream design data sheets for 161 major GPGP process and effluent streams. This stream design data provides an important base for evaluation of plant and process performance and for verification of the Department of Energy's ASPEN (Advanced System for Process Engineering) computer simulation models of the GPGP processes. 8 refs., 22 figs., 2 tabs.

  12. Interpreter Chart Diagram N-S

    OpenAIRE

    Mac Gaul Jorge, Marcia; Aballay, Patricia; Zamora, Rodrigo Gabriel; Soria, Marcelo A.

    2009-01-01

    The team of researchers develops and implements technological resources focused on a methodological strategy that supports its use. Our investigation deals with the analysis beginner students’ competences attending the Analisis de Sistema career at the UNSa, in order to solve different computing problems such as the analysis of the design if the diagram N-S and the desktop test. This work describes the process undertaken by the educational software design called Diagramar. Its development a...

  13. SPUDD: Stochastic Planning using Decision Diagrams

    OpenAIRE

    Hoey, Jesse; St-aubin, Robert; Hu, Alan; Boutilier, Craig

    2013-01-01

    Markov decisions processes (MDPs) are becoming increasing popular as models of decision theoretic planning. While traditional dynamic programming methods perform well for problems with small state spaces, structured methods are needed for large problems. We propose and examine a value iteration algorithm for MDPs that uses algebraic decision diagrams(ADDs) to represent value functions and policies. An MDP is represented using Bayesian networks and ADDs and dynamic programmin...

  14. Improving Web Database Access Using Decision Diagrams

    OpenAIRE

    Popel, Denis V.; Al-hakeem, Nawar

    2002-01-01

    In some areas of management and commerce, especially in Electronic commerce (E-commerce), that are accelerated by advances in Web technologies, it is essential to support the decision making process using formal methods. Among the problems of E-commerce applications: reducing the time of data access so that huge databases can be searched quickly; decreasing the cost of database design ... etc. We present the application of Decision Diagrams design using Information Theory ap...

  15. An experimental study of fluidization behavior using flow visualization and image processing

    International Nuclear Information System (INIS)

    A program of experimental study of fluidization of heavy spherical pellets with water using image processing technique has been started in the Nuclear Engineering Department of the Federal University of Rio Grande do Sul. Fluidization for application in nuclear reactors requires very detailed knowledge of its behavior as the reactivity is closely dependent on the porosity of the fluidized bed. A small modular nuclear reactor concept with suspended core is under study. A modified version of the reactor involves the choice of is to make conical the shape of the reactor core to produce a non-fluctuating bed and consequently guarantee the dynamic stability of the reactor. A 5 mm diameter steel ball are fluidized with water in a conical Plexiglass tube. A pump circulate the water in a loop feeding the room temperature water from the tank into the fluidization system and returning it back to the tank. A controllable valve controls the flow velocity. A high velocity digital CCD camera captures the images of the pellets moving in the fluidized tube. At different flow velocities, the individual pellets can be tracked by processing the sequential frames. A DVT digital tape record stores the images and by acquisition through interface board into a microcomputer. A special program process the data later on. Different algorithm of image treatment determines the velocity fields of the pellets. The behavior of the pellets under different flow velocity and porosity are carefully studw velocity and porosity are carefully studied. (author)

  16. Multiphysics numerical modeling of the continuous flow microwave-assisted transesterification process.

    Science.gov (United States)

    Muley, Pranjali D; Boldor, Dorin

    2012-01-01

    Use of advanced microwave technology for biodiesel production from vegetable oil is a relatively new technology. Microwave dielectric heating increases the process efficiency and reduces reaction time. Microwave heating depends on various factors such as material properties (dielectric and thermo-physical), frequency of operation and system design. Although lab scale results are promising, it is important to study these parameters and optimize the process before scaling up. Numerical modeling approach can be applied for predicting heating and temperature profiles including at larger scale. The process can be studied for optimization without actually performing the experiments, reducing the amount of experimental work required. A basic numerical model of continuous electromagnetic heating of biodiesel precursors was developed. A finite element model was built using COMSOL Multiphysics 4.2 software by coupling the electromagnetic problem with the fluid flow and heat transfer problem. Chemical reaction was not taken into account. Material dielectric properties were obtained experimentally, while the thermal properties were obtained from the literature (all the properties were temperature dependent). The model was tested for the two different power levels 4000 W and 4700 W at a constant flow rate of 840ml/min. The electric field, electromagnetic power density flow and temperature profiles were studied. Resulting temperature profiles were validated by comparing to the temperatures obtained at specific locations from the experiment. The results obtained were in good agreement with the experimental data. PMID:24432470

  17. A Signal Pre-processing Algorithm Applied for Ultrasonic Flow-Meter

    OpenAIRE

    Rang-ding Wang; Qiang Liu; Chen-tou Du; Ling Yao

    2013-01-01

    In order to solve the problem of time difference ultrasonic flow meter’s low accuracy, against the basic characteristics of the sample data, a data-processing algorithm is proposed. First, we use shell sort do a data pre-processing to the samples, then remove the error of the sample space by complex digital filter, and use the error compensation algorithm to get the final sample results. Among them, the complex digital filter is mainly composed by median filtering algorithm, sliding wind...

  18. Medição do inventário em processo e tempo de atravessamento em manufatura por modelagem em redes de Petri e diagrama de resultados / Measurement of work-in-process and manufacturing leadtime by Petri nets modeling and throughput diagram

    Scientific Electronic Library Online (English)

    Tiago, Facchin; Miguel Afonso, Sellitto.

    2008-08-01

    Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Este artigo apresenta um método para a medição de inventário em processo e tempo de atravessamento em um sistema de manufatura. O método consiste em modelar a manufatura por redes de Petri, simular o modelo em computador, alimentando-o com a situação de carga inicial dos processos e com um plano de [...] produção, obtendo os momentos simulados de conclusão de cada ordem do plano. Após este procedimento, com o uso do diagrama de resultados e da fórmula do funil, calcula-se o valor médio simulado de inventário em processo que o plano produzirá na manufatura. Ao fim, faz-se uma discussão na qual explora-se como os resultados do método podem ser úteis em decisões de gestão, envolvendo o inventário admitido, pulmões e restrições da manufatura. Abstract in english This paper presents a method to measure work-in-process and leadtime in a manufacturing system. The method consists of modeling manufacturing by Petri nets, providing as input for the model the initial load of the process and a production plan, running it and obtaining from the simulation the moment [...] s of completion of the orders. Using the throughput diagram and the funnel formula, we then calculate the mean simulated value of the work-in-process that the plan will produce in the manufacturing system. Finally, we discuss how the results can be used to underpin management decisions on issues such as actual work-in-process, buffers and manufacturing constraints.

  19. Flow Chemistry: Intelligent Processing of Gas-Liquid Transformations Using a Tube-in-Tube Reactor.

    Science.gov (United States)

    Brzozowski, Martin; O'Brien, Matthew; Ley, Steven V; Polyzos, Anastasios

    2015-02-17

    Conspectus The previous decade has witnessed the expeditious uptake of flow chemistry techniques in modern synthesis laboratories, and flow-based chemistry is poised to significantly impact our approach to chemical preparation. The advantages of moving from classical batch synthesis to flow mode, in order to address the limitations of traditional approaches, particularly within the context of organic synthesis are now well established. Flow chemistry methodology has led to measurable improvements in safety and reduced energy consumption and has enabled the expansion of available reaction conditions. Contributions from our own laboratories have focused on the establishment of flow chemistry methods to address challenges associated with the assembly of complex targets through the development of multistep methods employing supported reagents and in-line monitoring of reaction intermediates to ensure the delivery of high quality target compounds. Recently, flow chemistry approaches have addressed the challenges associated with reactions utilizing reactive gases in classical batch synthesis. The small volumes of microreactors ameliorate the hazards of high-pressure gas reactions and enable improved mixing with the liquid phase. Established strategies for gas-liquid reactions in flow have relied on plug-flow (or segmented flow) regimes in which the gas plugs are introduced to a liquid stream and dissolution of gas relies on interfacial contact of the gas bubble with the liquid phase. This approach confers limited control over gas concentration within the liquid phase and is unsuitable for multistep methods requiring heterogeneous catalysis or solid supported reagents. We have identified the use of a gas-permeable fluoropolymer, Teflon AF-2400, as a simple method of achieving efficient gas-liquid contact to afford homogeneous solutions of reactive gases in flow. The membrane permits the transport of a wide range of gases with significant control of the stoichiometry of reactive gas in a given reaction mixture. We have developed a tube-in-tube reactor device consisting of a pair of concentric capillaries in which pressurized gas permeates through an inner Teflon AF-2400 tube and reacts with dissolved substrate within a liquid phase that flows within a second gas impermeable tube. This Account examines our efforts toward the development of a simple, unified methodology for the processing of gaseous reagents in flow by way of development of a tube-in-tube reactor device and applications to key C-C, C-N, and C-O bond forming and hydrogenation reactions. We further describe the application to multistep reactions using solid-supported reagents and extend the technology to processes utilizing multiple gas reagents. A key feature of our work is the development of computer-aided imaging techniques to allow automated in-line monitoring of gas concentration and stoichiometry in real time. We anticipate that this Account will illustrate the convenience and benefits of membrane tube-in-tube reactor technology to improve and concomitantly broaden the scope of gas/liquid/solid reactions in organic synthesis. PMID:25611216

  20. Light-Element Reaction flow and the Conditions for r-Process Nucleosynthesis

    CERN Document Server

    Sasaqui, T; Mathews, G J

    2005-01-01

    We deduce new constraints on the entropy per baryon ($s/k$), dynamical timescale ($\\tau_{dyn}$), and electron fraction ($Y_{e}$) consistent with heavy element nucleosynthesis in the r-process. We show that the previously neglected reaction flow through the reaction sequence \\atg (n,$\\gamma$)\\Li significantly enhances the production of seed nuclei. We analyze the r-process nucleosynthesis in the context of a schematic exponential wind model. We show that fewer neutrons per seed nucleus implies that the entropy per baryon required for successful r-process nucleosynthesis must be more than a factor of two higher than previous estimates. This places new constraints on dynamical models for the r-process.

  1. Analyzing the Makespan using Processing Time Splitting Technique in Permutation Flow Shop Scheduling Problems

    Directory of Open Access Journals (Sweden)

    Baskar A

    2014-11-01

    Full Text Available In the shop floor, the production target is always a challenging job for any planning engineer. Meeting the due date is critical for the financial claims and marketing purposes. While scheduling, sometimes two or more operations are combined for processing and considered as a single job. Similarly, one machine may be overloaded with longer processing times. Some may be intentional, whereas, some may be unknowingly done. Clear definition of the processes and the corresponding spans before scheduling the jobs is highly significant for the speedy completion of all the jobs. In this paper, both the situations are analyzed with a numerical example. The effects of splitting the processing times and introducing an additional similar machine in the production line are studied for a permutation flow shop scheduling problem.

  2. Step bunching process induced by the flow of steps at the sublimated crystal surface

    CERN Document Server

    Zaluska-Kotur, M A; Krukowski, S

    2012-01-01

    Stepped GaN(0001) surface is studied by the kinetic Monte Carlo method and compared with the model based on Burton-Carbera-Frank equations. Successive stages of surface pattern evolution during high temperature sublimation process are discussed. At low sublimation rates clear, well defined step bunches form. The process happens in the absence or for very low Schwoebel barriers at the ideal surface. Bunches of several steps are well separated, move slowly and are rather stiff. Character of the process changes for more rapid sublimation process where double step formations become dominant and together with meanders and local bunches assemble into the less ordered surface pattern. Solution of the analytic equations written for one dimensional system confirms that step bunching is induced by the particle advection caused by step-flow anisotropy. This anisotropy becomes important when due to the low Schwoebel barrier both sides of step are symmetric. Simulations show that in the opposite limit of very high Schwoeb...

  3. Modeling of multiphase flow with solidification and chemical reaction in materials processing

    Science.gov (United States)

    Wei, Jiuan

    Understanding of multiphase flow and related heat transfer and chemical reactions are the keys to increase the productivity and efficiency in industrial processes. The objective of this thesis is to utilize the computational approaches to investigate the multiphase flow and its application in the materials processes, especially in the following two areas: directional solidification, and pyrolysis and synthesis. In this thesis, numerical simulations will be performed for crystal growth of several III-V and II-VI compounds. The effects of Prandtl and Grashof numbers on the axial temperature profile, the solidification interface shape, and melt flow are investigated. For the material with high Prandtl and Grashof numbers, temperature field and growth interface will be significantly influenced by melt flow, resulting in the complicated temperature distribution and curved interface shape, so it will encounter tremendous difficulty using a traditional Bridgman growth system. A new design is proposed to reduce the melt convection. The geometric configuration of top cold and bottom hot in the melt will dramatically reduce the melt convection. The new design has been employed to simulate the melt flow and heat transfer in crystal growth with large Prandtl and Grashof numbers and the design parameters have been adjusted. Over 90% of commercial solar cells are made from silicon and directional solidification system is the one of the most important method to produce multi-crystalline silicon ingots due to its tolerance to feedstock impurities and lower manufacturing cost. A numerical model is developed to simulate the silicon ingot directional solidification process. Temperature distribution and solidification interface location are presented. Heat transfer and solidification analysis are performed to determine the energy efficiency of the silicon production furnace. Possible improvements are identified. The silicon growth process is controlled by adjusting heating power and moving the side insulation layer upward. It is possible to produce high quality crystal with a good combination of heating and cooling. SiC based ceramic materials fabricated by polymer pyrolysis and synthesis becomes a promising candidate for nuclear applications. To obtain high uniformity of microstructure/concentration fuel without crack at high operating temperature, it is important to understand transport phenomena in material processing at different scale levels. In our prior work, a system level model based on reactive porous media theory was developed to account for the pyrolysis process in uranium-ceramic nuclear fabrication In this thesis, a particle level mesoscopic model based on the Smoothed Particle Hydrodynamics (SPH) is developed for modeling the synthesis of filler U3O8 particles and SiC matrix. The system-level model provides the thermal boundary conditions needed in the particle level simulation. The evolution of particle concentration and structure as well as composition of composite produced will be investigated. Since the process temperature and heat flux play the important roles in material quality and uniformity, the effects of heating rate at different directions, filler particle size and distribution on uniformity and microstructure of the final product are investigated. Uncertainty issue is also discussed. For the multiphase flow with directional solidification, a system level based on FVM is established. In this model, melt convection, temperature distribution, phase change and solidification interface can be investigated. For the multiphase flow with chemical reaction, a particle level model based on SPH method is developed to describe the pyrolysis and synthesis process of uranium-ceramic nuclear fuel. Due to its mesh-free nature, SPH can easily handle the problems with multi phases and components, large deformation, chemical reactions and even solidifications. A multi-scale meso-macroscopic approach, which combine a mesoscopic model based on SPH method and macroscopic model based on FVM, FEM and FDM, can be applied to even more com

  4. Overland flow generation processes in sub-humid Mediterranean forest stands

    Science.gov (United States)

    Ferreira, A. J. D.; Ferreira, C. S. S.; Coelho, C. O. A.; Walsh, R. P. D.; Shakesby, R. A.

    2012-04-01

    Forest soils in north and central Portugal have suffered and continue to suffer major structural changes as a result of forest management techniques, such as clear-felling and as a result of wildfire and rip-ploughing, which is carried out to prepare the ground for planting tree seedlings. In soils that have undergone these changes, the characteristics tend to be different for coniferous plantations, where the root system tends to die when the trees are cut following fire and subsequently may be consumed by fire to form a macropore network, and other types of tree plantations where the root system remains alive and allows regrowth from the sawn tree stumps. Overland flow thresholds decrease sharply as a result of rip-ploughing and forest fires and increase following clear-felling. The time taken for trees to reach maturity after wildfire differs markedly betwen the two main species (Pinus pinaster Aiton and Eucalyptus globulus Labill.) stands. In this paper, overland flow is considered in relation to rainfall, throughfall and throughflow, both in terms of hydrology and hydrochemistry in an attempt to understand overland flow generation mechanisms for a variety of forest land uses (mature pine and eucalyptus, pine seedling regrowth and eucalyptus regrowth from tree stumps, eucalyptus plantations and burned pine). Overland flow generation processes change sharply, even within a single rainfall event, as reflected in the soil hydrological processes and the hydrochemical fingerprints. These effects result from the different contact times for water and soil, which cause differences in the absorption and exhudation processes for the two species

  5. Reaction processes and permeability changes during CO2-rich brine flow through fractured Portland cement

    Science.gov (United States)

    Abdoulghafour, H.; Luquot, L.; Gouze, P.

    2012-12-01

    So far, cement alteration was principally studied experimentally using batch reactor (with static or renewed fluid). All exhibit similar carbonation mechanisms. The acidic solution, formed by the dissolution of the CO2 into the pore water or directly surrounding the cement sample, diffuses into the cement and induces dissolution reactions of the cement hydrates in particular portlandite and CSH. The calcium released by the dissolution of these calcium bearing phases combining with carbonate ions of the fluid forms calcium carbonates. The cement pH, initially around 13, falls to values where carbonate ion is the most dominant element (pH ~ 9), then CaCO3 phases can precipitate. These studies mainly associate carbonation process with a reduction of porosity and permeability. Indeed an increase of volume (about 10%) is expected during the formation of calcite from portlandite (equation 2) assuming a stoichiometric reaction. Here we investigated the cement alteration mechanisms in the frame of a controlled continuous renewal of CO2-rich fluid in a fracture. This situation is that expected when seepage is activated by the mechanical failure of the cement material that initially seals two layers of distinctly different pressure: the storage reservoir and the aquifer above the caprock, for instance. We study the effect of flow rates from quasi-static flow to higher flow rates for well-connected fractures. In the quasi-static case we observed an extensive conversion of portlandite (Ca(OH)2) to calcite in the vicinity of the fracture similar to that observed in the published batch experiments. Eventually, the fracture was almost totally healed. The experiments with constant flow revealed a different behaviour triggered by the continuous renewing of the reactants and withdrawal of reaction products. We showed that calcite precipitation is more efficient for low flow rate. With intermediate flow rate, we measured that permeability increases slowly at the beginning of the experiment and then remains constant due to calcite precipitation in replacement of CSH and CH into fracture border. With higher flow rate, we measured a constant permeability which can be explained by the development of a highly hydrated Si-rich zone which maintains the initial fracture aperture during all over the experiment while noticeable mass is released from the sample. These preliminary results emphasize that more complex behaviours than that envisaged from batch experiments may take place in the vicinity of flowing fractures. We demonstrated that if only micro-cracks appear in the cement well, carbonation reaction may heal these micro-cracks and mitigate leakage whereas conductive fractures allowing high flow may represent a risk of perennial leakage because the net carbonation process, including the calcite precipitation and its subsequent re-dissolution, is sufficiently to heal the fracture. However, the precipitation of Si-rich amorphous phases may maintain the initial fracture aperture and limit the leakage rate. Keywords: leakage, cement alteration, flow rate, fracture, permeability changes, reaction processes.

  6. Transient Heat and Material Flow Modeling of Friction Stir Processing of Magnesium Alloy using Threaded Tool

    Science.gov (United States)

    Yu, Zhenzhen; Zhang, Wei; Choo, Hahn; Feng, Zhili

    2012-02-01

    A three-dimensional transient computational fluid dynamics (CFD) model was developed to investigate the material flow and heat transfer during friction stir processing (FSP) in an AZ31B magnesium alloy. The material was assumed to be a non-Newtonian viscoplastic fluid, and the Zener-Hollomon parameter was used to describe the dependence of material viscosity on temperature and strain rate. The material constants used in the constitutive equation were determined experimentally from compression tests of the AZ31B Mg alloy under a wide range of strain rates and temperatures. A dynamic mesh method, combining both Lagrangian and Eulerian formulations, was used to capture the material flow induced by the movement of the threaded tool pin. Massless inert particles were embedded in the simulation domain to track the detailed history of material flow. The actual FSP was also carried out on a wrought Mg plate where temperature profiles were recorded by embedding thermocouples. The predicted transient temperature history was found to be consistent with that measured during FSP. Finally, the influence of the thread on the simulated results of thermal history and material flow was studied by comparing two models: one with threaded pin and the other with smooth pin surface.

  7. Relationship Between Storm Hydrograph Components and Subsurface Flow Processes in a Hilly Headwater Basin, Toyota, Japan

    Science.gov (United States)

    Tsujimura, M.; Asai, K.; Takei, R.

    2001-05-01

    Temporal and spatial distribution of tracer elements and subsurface flow processes were investigated to study relationship between storm hydrograph components and behavior of subsurface water in a headwater catchment of Toyota Hill, Aichi prefecture, central Japan. The catchment has an area of 0.857 ha with an altitude of 60 to 100 m, and is underlain by granite. The soil depth revealed by sounding test ranges from 0.5 to 4.0 m. Rain, stream, soil and ground waters were sampled once in a week, and the stream water was sampled at 5 to 60 minute intervals during rainstorms. The pressure head of subsurface water was monitored using tensiometers and piezometers nests, and the stream flow was monitored using V-notch weir. The stable isotopic ratios of deuterium and oxygen 18 and inorganic ion concentrations were determined on all water samples. The oxygen 18 isotopic ratio in stream water decreased with rainfall during the rainstorms. The ratio of event water component to the total runoff water at the peak discharge ranged from 16 to 92 %, and the event water ratio correlated with the peak discharge rate and rainfall intensity. The tesiometric data showed that the shallow subsurface water with low isotopic ratios at the lower slope discharged directly to the stream during the heavy rainstorms. The shallow subsurface flow at the lower slope and overland flow on the raiparian zone contributed much to the stream water chemistry during heavy rainstorms.

  8. Characteristics of two-phase condensing flow by visualization using computed image processing

    International Nuclear Information System (INIS)

    The mechanics of the condensing behavior of vapor bubbles in a subcooled bulk flow is complicated and influenced by both heat and mass transfer. To examine the characteristics of such thermal-nonequilibrium two-phase flow, experimental and analytical researches have been made. In the experiment, the movement of each vapor bubble in a flowing channel was recorded on video tapes and analyzed by an image processing system. As result, the distributions of void fraction along the test section were obtained. In the analysis, a simple analytical model was introduced to predict the distributions of void fraction and liquid subcooling temperature. By considering the rate of vapor condensation along the flow direction, the differntial equation of energy balance between two phases was obtained. Integration of this equation yielded the void fraction and bulk liquid subcooling at any position. The condensation rate was estimated as a function of the local liquid subcooling, interfacial area and mass velocity. Finally, a close fit between calculated results and experimental data was obtained. (orig.)

  9. Development of an entrained flow gasifier model for process optimization study

    Energy Technology Data Exchange (ETDEWEB)

    Biagini, E.; Bardi, A.; Pannocchia, G.; Tognotti, L. [Consorzio Pisa Ric, Pisa (Italy). Div Energia Ambiente

    2009-10-15

    Coal gasification is a versatile process to convert a solid fuel in syngas, which can be further converted and separated in hydrogen, which is a valuable and environmentally acceptable energy carrier. Different technologies (fixed beds, fluidized beds, entrained flow reactors) are used, operating under different conditions of temperature, pressure, and residence time. Process studies should be performed for defining the best plant configurations and operating conditions. Although 'gasification models' can be found in the literature simulating equilibrium reactors, a more detailed approach is required for process analysis and optimization procedures. In this work, a gasifier model is developed by using AspenPlus as a tool to be implemented in a comprehensive process model for the production of hydrogen via coal gasification. It is developed as a multizonal model by interconnecting each step of gasification (preheating, devolatilization, combustion, gasification, quench) according to the reactor configuration, that is in entrained flow reactor. The model removes the hypothesis of equilibrium by introducing the kinetics of all steps and solves the heat balance by relating the gasification temperature to the operating conditions. The model allows to predict the syngas composition as well as quantity the heat recovery (for calculating the plant efficiency), 'byproducts', and residual char. Finally, in view of future works, the development of a 'gasifier model' instead of a 'gasification model' will allow different reactor configurations to be compared.

  10. Modeling of the flow stress for AISI H13 Tool Steel during Hard Machining Processes

    International Nuclear Information System (INIS)

    In general, the flow stress models used in computer simulation of machining processes are a function of effective strain, effective strain rate and temperature developed during the cutting process. However, these models do not adequately describe the material behavior in hard machining, where a range of material hardness between 45 and 60 HRC are used. Thus, depending on the specific material hardness different material models must be used in modeling the cutting process. This paper describes the development of a hardness-based flow stress and fracture models for the AISI H13 tool steel, which can be applied for range of material hardness mentioned above. These models were implemented in a non-isothermal viscoplastic numerical model to simulate the machining process for AISI H13 with various hardness values and applying different cutting regime parameters. Predicted results are validated by comparing them with experimental results found in the literature. They are found to predict reasonably well the cutting forces as well as the change in chip morphology from continuous to segmented chip as the material hardness change

  11. Modern approaches to processing large hyperspectral and multispectral aerospace data flows

    Science.gov (United States)

    Bondur, V. G.

    2014-12-01

    We consider approaches to processing large hyperspectral and multispectral imaging flows produced in aerospace monitoring for solving a wide range of problems of management of natural resources, environmental security, prevention of natural disasters and technogenic accidents, as well as problems of real economy, and basic and applied sciences. We analyze the specific features of the phases of hyperspectral data analysis and describe a software and hardware system that uses new and improved methods and algorithms for processing large flows of hyperspectral and other aerospace data and has a high-performance computer. This system contains different types of software for identifying the types of given objects by solving inverse problems of remote sensing as well as by analyzing their qualitative and quantitative characteristics, combined multiparameter processing of hyperspectral aerospace data, tracking the local changes including those related to changes in meteorological conditions and vegetation periods, detecting and identifying the types of small objects on the basis of analysis of individual parts of the image, detecting and identifying heat sources, etc. We bring examples of processing of hyperspectral and multispectral satellite images with the help of software and hardware tools developed.

  12. Inline chemical process analysis in micro-plants based on thermoelectric flow and impedimetric sensors

    International Nuclear Information System (INIS)

    In micro-plants, as used in chemical micro-process engineering, an integrated inline analytics is regarded as an important factor for the development and optimization of chemical processes. Up to now, there is a lack of sensitive, robust and low-priced micro-sensors for monitoring mixing and chemical conversion in micro-fluidic channels. In this paper a novel sensor system combining an impedimetric sensor and a novel pressure stable thermoelectric flow sensor for monitoring chemical reactions in micro-plants is presented. The CMOS-technology-based impedimetric sensor mainly consists of two capacitively coupled interdigital electrodes on a silicon chip. The thermoelectric flow sensor consists of a heater in between two thermopiles on a perforated membrane. The pulsed and constant current feeds of the heater were analyzed. Both sensors enable the analysis of chemical conversion by means of changes in the thermal and electrical properties of the liquid. The homogeneously catalyzed synthesis of n-butyl acetate as a chemical model system was studied. Experimental results revealed that in an overpressure regime, relative changes of less than 1% in terms of thermal and electrical properties can be detected. Furthermore, the transition from one to two liquid phases accompanied by the change in slug flow conditions could be reproducibly detected

  13. Potentiometric electronic tongue-flow injection analysis system for the monitoring of heavy metal biosorption processes.

    Science.gov (United States)

    Wilson, D; del Valle, M; Alegret, S; Valderrama, C; Florido, A

    2012-05-15

    An automated flow injection potentiometric (FIP) system with electronic tongue detection (ET) is used for the monitoring of biosorption processes of heavy metals on vegetable wastes. Grape stalk wastes are used as biosorbent to remove Cu(2+) ions in a fixed-bed column configuration. The ET is formed by a 5-sensor array with Cu(2+) and Ca(2+)-selective electrodes and electrodes with generic response to heavy-metals, plus an artificial neural network response model of the sensor's cross-response. The real-time monitoring of both the Cu(2+) and the cation exchanged and released (Ca(2+)) in the effluent solution is performed by using flow-injection potentiometric electronic tongue system. The coupling of the electronic tongue with automation features of the flow-injection system allows us to accurately characterize the Cu(2+) ion-biosorption process, through obtaining its breakthrough curves, and the profile of the Ca(2+) ion release. In parallel, fractions of the extract solution are analysed by spectroscopic techniques in order to validate the results obtained with the reported methodology. The sorption performance of grape stalks is also evaluated by means of well-established sorption models. PMID:22483912

  14. River flow forecasting with Artificial Neural Networks using satellite observed precipitation pre-processed with flow length and travel time information: case study of the Ganges river basin

    Directory of Open Access Journals (Sweden)

    M. K. Akhtar

    2009-04-01

    Full Text Available This paper explores the use of flow length and travel time as a pre-processing step for incorporating spatial precipitation information into Artificial Neural Network (ANN models used for river flow forecasting. Spatially distributed precipitation is commonly required when modelling large basins, and it is usually incorporated in distributed physically-based hydrological modelling approaches. However, these modelling approaches are recognised to be quite complex and expensive, especially due to the data collection of multiple inputs and parameters, which vary in space and time. On the other hand, ANN models for flow forecasting are frequently developed only with precipitation and discharge as inputs, usually without taking into consideration the spatial variability of precipitation. Full inclusion of spatially distributed inputs into ANN models still leads to a complex computational process that may not give acceptable results. Therefore, here we present an analysis of the flow length and travel time as a basis for pre-processing remotely sensed (satellite rainfall data. This pre-processed rainfall is used together with local stream flow measurements of previous days as input to ANN models. The case study for this modelling approach is the Ganges river basin. A comparative analysis of multiple ANN models with different hydrological pre-processing is presented. The ANN showed its ability to forecast discharges 3-days ahead with an acceptable accuracy. Within this forecast horizon, the influence of the pre-processed rainfall is marginal, because of dominant influence of strongly auto-correlated discharge inputs. For forecast horizons of 7 to 10 days, the influence of the pre-processed rainfall is noticeable, although the overall model performance deteriorates. The incorporation of remote sensing data of spatially distributed precipitation information as pre-processing step showed to be a promising alternative for the setting-up of ANN models for river flow forecasting.

  15. Experimental and theoretical study of flowing foam and of the liquid film formed on the wall for the improvement of decontamination processes using foams

    International Nuclear Information System (INIS)

    Amongst chemical decontamination techniques, the foam cleaning process has the advantage of reducing the amount of liquid used, thus limiting the quantity of the chemical reagents and the secondary waste volume. In order to improve this process, it is essential to understand the behaviour of the foam in the vicinity of the contaminated surface. Two methods of study have been initiated. Firstly, the characterization of the liquid film formed on the wall, and secondly, the characterization of the foam bed. Furthermore, our goal is to set up a drainage model which enables a choice of process parameters. Flush-mounted conductance probes have been developed in order to determine the thickness of the liquid film at the surface and the foam liquid fraction. The influence of the foam on the film structure and the interpretation of the thickness measured is discussed. The process studied consists of filling the facility with foam and letting the foam drain once the facility is full. It was demonstrated that the liquid film thickness varies between a few microns and 50 ?m and that the value depends on position and time. Furthermore, a strong correlation links the film thickness and the foam liquid fraction. A drift-flux model has been built to describe the drainage of the upstream flow or static foam. The model is solved by using the method of characteristics. Analytical solutions are obtained and the liquid fraction evolution can easily be represented on a single diagram. The parameters of the void-drift closure law have been deducted from the experiments. The comparison to experimental data has shown that the model is well adapted. The laboratory therefore has experimental and theoretical equipment to study any foam. Finally, the model is applied to realistic decontamination configurations in order to present how determine the parameters of the process. (author)

  16. Analysis and Design of the Input and Output Attributes of the Dynamic Simulation code for the H{sub 2}SO{sub 4} distillation process

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Ji Woon; Shin, Young Joon; Kim, Ji Hwan; Lee, Ki Young; Lee, Won Jae; Chang, Jong Hwa [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Youn, Cheung [Chungnam National University, Daejeon (Korea, Republic of)

    2009-10-15

    The dynamic simulation code for the H{sub 2}SO{sub 4} distillation process was developed by the KAERI research group in 2007. The analysis and design of the input and output attributes are usually required for the effective compilation of the dynamic simulation program. The Data Flow Diagram (DFD) and the class diagram have been used for the analysis and design of the input and output attributes. In this paper, the data flows for dynamic simulation of the H{sub 2}SO{sub 4} distillation process have been embodied by using the DFD and the input and output attributes have also been defined by using the class diagram.

  17. Assessment of controlling processes for field-scale uranium reactive transport under highly transient flow conditions

    Science.gov (United States)

    Ma, Rui; Zheng, Chunmiao; Liu, Chongxuan; Greskowiak, Janek; Prommer, Henning; Zachara, John M.

    2014-02-01

    This paper presents the results of a comprehensive model-based analysis of a uranyl [U(VI)] tracer test conducted at the U.S. DOE Hanford 300 Area (300A) IFRC. Despite the highly complex field conditions the numerical three-dimensional multicomponent reactive transport model was able to capture most of the spatiotemporal variations of the observed U(VI) concentrations. A multimodel analysis was performed to interrogate the relative importance of various processes and factors for controlling field-scale reactive transport during the uranyl tracer test. The results indicate that multirate sorption/desorption, surface complexation reactions, and initial concentration distributions were the most important processes and factors controlling U(VI) migration. On the other hand, cation exchange reactions, the choice of the surface complexation model, and dual-domain mass transfer processes played less important roles under the prevailing field-test conditions. Further analysis of the modeling results demonstrates that these findings are conditioned to the relatively stable groundwater chemistry and the selected length of the field experimental duration (16 days). The model analysis also revealed the crucial role of the intraborehole flow that occurred within the long-screened monitoring wells and thus affected both field measurements and simulated U(VI) concentrations as a combined effect of aquifer heterogeneity and dynamic flow conditions. This study provides the first highly data-constrained uranium transport simulations under highly dynamic flow conditions. It illustrates the value of reactive transport modeling for elucidating the relative importance of individual processes in controlling uranium transport under specific field-scale conditions.

  18. Single pass tangential flow filtration to debottleneck downstream processing for therapeutic antibody production.

    Science.gov (United States)

    Dizon-Maspat, Jemelle; Bourret, Justin; D'Agostini, Anna; Li, Feng

    2012-04-01

    As the therapeutic monoclonal antibody (mAb) market continues to grow, optimizing production processes is becoming more critical in improving efficiencies and reducing cost-of-goods in large-scale production. With the recent trends of increasing cell culture titers from upstream process improvements, downstream capacity has become the bottleneck in many existing manufacturing facilities. Single Pass Tangential Flow Filtration (SPTFF) is an emerging technology, which is potentially useful in debottlenecking downstream capacity, especially when the pool tank size is a limiting factor. It can be integrated as part of an existing purification process, after a column chromatography step or a filtration step, without introducing a new unit operation. In this study, SPTFF technology was systematically evaluated for reducing process intermediate volumes from 2× to 10× with multiple mAbs and the impact of SPTFF on product quality, and process yield was analyzed. Finally, the potential fit into the typical 3-column industry platform antibody purification process and its implementation in a commercial scale manufacturing facility were also evaluated. Our data indicate that using SPTFF to concentrate protein pools is a simple, flexible, and robust operation, which can be implemented at various scales to improve antibody purification process capacity. PMID:22094920

  19. Modeling of temperature field and fluid flow in hybrid welding process

    Directory of Open Access Journals (Sweden)

    W. Piekarska

    2009-07-01

    Full Text Available Mathematical and numerical model of the temperature field and the velocity field in melted zone concerning the hybrid laser – arc process was presented in this paper. The temperature field was determined by solution the transient heat transfer equation with activity of inner heat sources. Fluid flow in welding pool was determined by solution of the Navier – Stokes equation in Chorin’s projection. The fuzzy solidification front was assumed in a numerical algorithm with linear approximation of the solid phase in mushy zone. Fluid flow through porous medium was considered in mushy zone according to Darcy’s model. In the base of elaborated models and realized algorithms, results of computer simulations were presented in this study. Temperature distribution in the weld and velocity distribution in melted zone as well as welding pool shape and heat affected zone were illustrated.

  20. Design of Natural Fiber Composites Chemical Container Using Resin Flow Simulation of VARTML Process

    Directory of Open Access Journals (Sweden)

    Changduk Kong

    2014-08-01

    Full Text Available In this study, an investigation on mechanical properties of flax natural fiber composite is performed as a precedent study on the design of eco-friendly structure using flax natural fiber composite. The Vacuum Assisted Resin Transfer Molding-Light (VARTML manufacturing method is adopted for manufacturing the flax fiber composite panel. The VARTML is a manufacturing process that the resin is injected into the dry layered –up fibers enclosed by a rigid mold tool under vacuum. In this work, the resin flow analysis of VARTM manufacturing method is performed. A series of flax composite panels are manufactured, and several kinds of specimens cut out from the panels are tested to obtain mechanical performance data. Based on this, structural design of chemical storage tank for agricultural vehicle was performed using flax/vinyl ester. After structural design and analysis, the resin flow analysis of VARTM manufacturing method was performed

  1. Code Development for Unsteady Inlet Flows using Parallel Processing, Iced Airfoils

    Science.gov (United States)

    Chung, Joongkee

    1997-01-01

    As a part of an effort for the development of an "Integrated Solution Process for Iced Airfoils" which combines a CFD (Computational Fluid Dynamics) code and an ice accretion code for accurate prediction of ice growth and performance degradation, a study on the effect of iced-geometry-smoothing was initiated. As a first step in this study, the degree of smoothing was defined by the number of control points for the given iced airfoil geometry. Then, reducing these number of control points in a systematical way provided various degrees of grid generation. This study will be continued by comparing CFD computed data such as pressure, lift, drag, flow separation, and wake flow patterns between the iced airfoils against any existing experimental data.

  2. Reheating Phase Diagram for Higgs Inflation

    CERN Document Server

    Cai, Rong-Gen; Wang, Shao-Jiang

    2015-01-01

    We investigate the impact on the inflationary predictions from various reheating histories which are characterized by an e-folding number $N_{\\mathrm{reh}}$ and an effective equation-of-state parameter $w_{\\mathrm{reh}}$ during reheating process. For Higgs inflation with a non-minimal coupling to gravity, the predictions are obtained on the $N_{\\mathrm{reh}}\\!\\!-\\!w_{\\mathrm{reh}}$ reheating phase diagram. We find that the predictions are insensitive to reheating phase. Within the $1\\sigma$ region of the scalar spectral index $n_s$ reported by Planck 2014 Preliminary, almost all possible reheating histories are allowed on the reheating phase diagram, where Higgs inflation with canonical reheating history $w_{\\mathrm{reh}}=0$ lies near the upper edge of the $1\\sigma$ range of $n_s$. Future measurements of $n_s$ with high precision will identify the reheating physics of Higgs inflation.

  3. FPGA Implementations of Ladder Diagrams

    OpenAIRE

    Neil William Bergmann; Peter Waldeck; Shukla, Sunil K.

    2013-01-01

    The performance of programmable logic controllers is often constrained by the microprocessor and the real-time firmware of the controller. Field programmable gate arrays (FPGAs) are an attractive potential implementation medium for high-speed control because of their fast and parallel execution and programmable nature. Ladder Diagrams are a standard graphical programming method for industrial controllers, but compilers from Ladder Diagrams to FPGA hardware do not yet exist. This paper explore...

  4. Category Theory Using String Diagrams

    OpenAIRE

    Marsden, Daniel

    2014-01-01

    In work of Fokkinga and Meertens a calculational approach to category theory is developed. The scheme has many merits, but sacrifices useful type information in the move to an equational style of reasoning. By contrast, traditional proofs by diagram pasting retain the vital type information, but poorly express the reasoning and development of categorical proofs. In order to combine the strengths of these two perspectives, we propose the use of string diagrams, common folklor...

  5. Diagrams of the polaron model

    International Nuclear Information System (INIS)

    A systematic treatment of the perturbation theory for polaron energy is given on the basis of diagram technique. Feynman diagrams constructed allow us to calculate the polaron energy up to the third order in powers of the coupling constant expansions thus obtained are of the form, rspectively: E/?=-?-1,591962(?/10)2-0,806(?/103+. .., N=?/2+3,183924(?/10)2+2,82(?/10)3+..

  6. Time exceptions in sequence diagrams

    OpenAIRE

    Halvorsen, Oddleif; Runde, Ragnhild Kobro; Haugen, Øystein

    2008-01-01

    UML sequence diagrams partially describe a system. We show how the description may be augmented with exceptions triggered by the violation of timing constraints and compare our approach to those of the UML 2.1 simple time model, the UML Testing Profile and the UML profile for Schedulability, Performance and Time. We give a formal definition of time exceptions in sequence diagrams and show that the concepts are compositional. An ATM example is used to explain and motivate the concepts.

  7. Frequency pattern of turbulent flow and sediment entrainment over ripples using image processing

    Directory of Open Access Journals (Sweden)

    A. Keshavarzi

    2012-01-01

    Full Text Available River channel change and bed scourings are source of major environmental problem for fish and aquatic habitat. The bed form such as ripples and dunes is the result of an interaction between turbulent flow structure and sediment particles at the bed. The structure of turbulent flow over ripples is important to understand initiation of sediment entrainment and its transport. The focus of this study is the measurement and analysis of the dominant bursting events and the flow structure over ripples in the bed of a channel. Two types of ripples with sinusoidal and triangular forms were tested in this study. The velocities of flow over the ripples were measured in three dimensions using an Acoustic Doppler Velocimeter with a sampling rate of 50 Hz. These velocities were measured at different points within the flow depth from the bed and at different longitudinal positions along the flume. A CCD camera was used to capture 1500 sequential images from the bed and to monitor sediment movement at different positions along the bed. Application of image processing technique enabled us to compute the number of entrained and deposited particles over the ripples. From a quadrant decomposition of instantaneous velocity fluctuations close to the bed, it was found that bursting events downstream of the second ripple, in Quadrants 1 and 3, were dominant whereas upstream of the ripple, Quadrants 2 and 4 were dominant. More importantly consideration of these results indicates that the normalized occurrence probabilities of sweep events along the channel are in phase with the bed forms whereas those of ejection events are out of phase with the bed form. Therefore entrainment would be expected to occur upstream and deposition occurs downstream of the ripple. These expectations were confirmed by measurement of entrained and deposited sediment particles from the bed. These above information can be used in practical application for rivers where restoration is required.

  8. Atomistic processes controlling flow stress scaling during compression of nanoscale face-centered-cubic crystals

    International Nuclear Information System (INIS)

    Highlights: ? We generate complex networks of dislocations in Cu nanopillars by atomistic method. ? Their evolution during compression is examined as a function of pillar diameter. ? Sub-75nm Cu pillars show same flow stress scaling than past compression experiments. ? A deformation mechanism map is developed for Cu crystals with different diameters. ? We elucidate the atomistic origin of size-dependent plasticity in Cu nanocrystals. - Abstract: The size dependence of strength observed in submicrometer face-centered-cubic (fcc) metallic crystals under uniform deformation depends on the interaction of pre-existing dislocations with surfaces. To date, however, the dislocation processes controlling flow stress scaling in fcc crystals less than 100 nm in size have remained an open question due to limited knowledge on microstructural evolution during deformation in such small volumes. Here, molecular dynamics computer simulations employing a technique of high-temperature annealing and quenching on porous crystals were used to generate complex dislocation microstructures in sub-75 nm Cu pillars with high initial dislocation densities of 1016 m-2, which made it possible to quantitatively examine their evolution during compression as a function of pillar diameter. These simulations reveal a transition from a state of dislocation exhaustion, where mobile dislocations are lost at the free surface and the dislocation density steadily decreases, ton density steadily decreases, to a regime of intermittent plastic flow between elastic loading and source-limited activation inside the pillars. It is shown that plastic flow stresses predicted during dislocation exhaustion regime exhibit little to no size dependence, while pronounced size effects are found during source-limited activation. Remarkably, the relationship between flow stress predicted at 5% strain and diameter is found to follow closely the power-law dependence reported in past experiments with larger Cu crystals and smaller densities. A deformation mechanism map, expressed in terms of diameter, is developed and used to elucidate the origin of size-dependent plasticity in nanoscale fcc crystals.

  9. The process and potential of nitrate attenuation in the aquifers with different scale of flow system

    Science.gov (United States)

    Saito, M.; Onodera, S.

    2009-12-01

    Nitrate (NO3-) is a widespread pollutant derived from human activities. Many studies have confirmed that agricultural practices such as fertilizer application have resulted in nitrate contamination of groundwater (Burt et al., 1993; Mueller et al., 1995; Böhlke, 2002). Also in the developing megacities, groundwater pollution by nitrate is a severe environmental problem because of the huge amount of domestic and industrial wastewater (Onodera et al., 2008; Umezawa et al., 2008). For the sustainable use of groundwater resources for the future, it is important to clarify about the natural function of nitrate attenuation such as denitrification process in groundwater. The previous studies have shown the nitrate attenuation by denitrification process in groundwater of the riparian wetlands (Hill et al., 2000; Böhlke et al., 2002), floodplain (Fustec et al., 1991; Tesoriero et al., 2000) or coastal area (Howard, 1985; Uchiyama et al., 2000) with relatively gentle topographic gradient. In recent years, several researchers have suggested that landscape hydrogeology can provide an important framework for understanding nitrate removal capacity at the riparian zones (Hill, 1996; Baker et al., 2001; Vidon & Hill, 2004). However, few studies discussed about the relation between groundwater flow condition and denitrification process on the catchment scales. The objective this study is to examine the process and potential of nitrate attenuation in the aquifers with the different scale of flow system. We compared the data on the groundwater flow, nitrate concentration and nitrogen stable isotope ratio (?15N) in groundwater in the three study sites (IK, YD and JK). All these study areas are characterized by the large nitrogen load from agricultural, domestic and industrial activities. The IK (Ikuchijima) aquifer is located in southern Japan with the catchment area of 44ha and topographic gradient of 1/50. The YD (Yellow River Delta) aquifer is located on the lower reaches of the Yellow River, which covers approximately 5200km2 and topographic gradient is approximately 1/1000. The JK (Jakarta) aquifer is located on the metropolitan area of Jakarta that is lower reaches of the Ciliwung River catchment and the topographic gradient is approximately 1/400. In the all study sites, NO3--N attenuation with the groundwater flow was confirmed, and groundwater in the recharge area is characterized by relatively high concentrations of NO3--N and relatively low ?15N, while the groundwater of the discharge area is characterized by relatively low concentrations of NO3--N and relatively high ?15N. This result suggests isotope enrichment by denitrification process. Especially in the YD, isotope enrichment ratio is higher than the other two sites.

  10. On image pre-processing for PIV of single- and two-phase flows over reflecting objects

    Energy Technology Data Exchange (ETDEWEB)

    Deen, Niels G.; Willems, Paul; Sint Annaland, Martin van; Kuipers, J.A.M.; Lammertink, Rob G.H.; Kemperman, Antoine J.B.; Wessling, Matthias; Meer, Walter G.J. van der [University of Twente, Faculty of Science and Technology, Institute of Mechanics, Processes and Control Twente (IMPACT), Enschede (Netherlands)

    2010-08-15

    A novel image pre-processing scheme for PIV of single- and two-phase flows over reflecting objects which does not require the use of additional hardware is discussed. The approach for single-phase flow consists of image normalization and intensity stretching followed by background subtraction. For two-phase flow, an additional masking step is added after the background subtraction. The effectiveness of the pre-processing scheme is shown for two examples: PIV of single-phase flow in spacer-filled channels and two-phase flow in these channels. The pre-processing scheme increased the displacement peak detectability significantly and produced high quality vector fields, without the use of additional hardware. (orig.)

  11. An Approach to Code Generation from UML Diagrams

    OpenAIRE

    Gurad, Harshal D.; Mahalle, V. S.

    2014-01-01

    The Unified Modeling Language (UML) has now become the de-facto industry standard for object-oriented (OO) software development. UML provides a set of diagrams to model structural and behavioral aspects of an object-oriented system. Automatic translation of UML diagrams to object oriented code is highly desirable because it eliminates the chances of introduction of human errors in the translation process. Automatic code generation is efficient which, in turn, helps the softwar...

  12. On Hardy's paradox, weak measurements, and multitasking diagrams

    International Nuclear Information System (INIS)

    We discuss Hardy's paradox and weak measurements by using multitasking diagrams, which are introduced to illustrate the progress of quantum probabilities through the double interferometer system. We explain how Hardy's paradox is avoided and elaborate on the outcome of weak measurements in this context. -- Highlights: ? Hardy's paradox explained and eliminated. ? Weak measurements: what is really measured? ? Multitasking diagrams: introduced and used to discuss quantum mechanical processes.

  13. Erosion estimation for NPP turbine blades using generalized diagram

    International Nuclear Information System (INIS)

    Generalized data on estimation criteria of erosion fracture used with various plants and companies are given as well as a generalized diagram for determining erosion characteristics of a stage on partial loads. An example of using the generalized diagram for determining relative change in unloading range of NPP powerful turbine depending on humidity at the end of the steam expansion process and reserve for admissible erosion is given

  14. Toxic metals in WEEE: Characterization and substance flow analysis in waste treatment processes

    International Nuclear Information System (INIS)

    Waste electrical and electronic equipment (WEEE) has received extensive attention as a secondary source of metals. Because WEEE also contains toxic substances such as heavy metals, appropriate management of these substances is important in the recycling and treatment of WEEE. As a basis for discussion toward better management of WEEE, this study characterizes various types of WEEE in terms of toxic metal contents. The fate of various metals contained in WEEE, including toxic metals, was also investigated in actual waste treatment processes. Cathode-ray tube televisions showed the highest concentration and the largest total amount of toxic metals such as Ba, Pb, and Sb, so appropriate recycling and disposal of these televisions would greatly contribute to better management of toxic metals in WEEE. A future challenge is the management of toxic metals in mid-sized items such as audio/visual and ICT equipment because even though the concentrations were not high in these items, the total amount of toxic metals contained in them is not negligible. In the case of Japan, such mid-sized WEEE items as well as small electronic items are subject to municipal solid waste treatment. A case study showed that a landfill was the main destination of toxic metals contained in those items in the current treatment systems. The case study also showed that changes in the flows of toxic metals will occur when treatment processes are modified to emphasize resource recovery. Because the flow changes might lead to an increase in the amount of toxic metals released to the environment, the flows of toxic metals and the materials targeted for resource recovery should be considered simultaneously. - Highlights: ? Appropriate management of toxic metals contained in WEEE is important during recycling and treatment of WEEE. ? CRT TVs contain large amount of toxic metals with high concentration and thus appropriate management is highly important. ? Mid-sized equipment is a future target for managing toxic metals in WEEE because the total amount is not negligible. ? Changes in the flows of toxic metals will occur when treatment processes are modified to emphasize resource recovery. ? The flows of toxic metals and valuable materials should be managed simultaneously in recycling and treatment of WEEE

  15. Teaching groundwater flow processes: connecting lecture to practical and field classes

    Science.gov (United States)

    Hakoun, V.; Mazzilli, N.; Pistre, S.; Jourde, H.

    2013-05-01

    Preparing future hydrogeologists to assess local and regional hydrogeological changes and issues related to water supply is a challenging task that creates a need for effective teaching frameworks. The educational literature suggests that hydrogeology courses should consistently integrate lecture class instructions with practical and field classes. However, most teaching examples still separate these three class components. This paper presents an introductory course to groundwater flow processes taught at Université Montpellier 2, France. The adopted pedagogical scheme and the proposed activities are described in details. The key points of the proposed scheme for the course are: (i) iterations into the three class components to address groundwater flow processes topics, (ii) a course that is structured around a main thread (well testing) present in each class component, and (iii) a pedagogical approach that promotes active learning strategies, in particular using original practical classes and field experiments. The experience indicates that the proposed scheme improves the learning process, as compared to a classical, teacher-centered approach.

  16. The study of flow pattern and phase-change problem in die casting process

    Science.gov (United States)

    Wang, T. S.; Wei, H.; Chen, Y. S.; Shang, H. M.

    1996-01-01

    The flow pattern and solidification phenomena in die casting process have been investigated in the first phase study. The flow pattern in filling process is predicted by using a VOF (volume of fluid) method. A good agreement with experimental observation is obtained for filling the water into a die cavity with different gate geometry and with an obstacle in the cavity. An enthalpy method has been applied to solve the solidification problem. By treating the latent heat implicitly into the enthalpy instead of explicitly into the source term, the CPU time can be reduced at least 20 times. The effect of material properties on solidification fronts is tested. It concludes that the dependence of properties on temperature is significant. The influence of the natural convection over the diffusion has also been studied. The result shows that the liquid metal solidification phenomena is diffusion dominant, and the natural convection can affect the shape of the interface. In the second phase study, the filling and solidification processes will be considered simultaneously.

  17. MODELING COUPLED PROCESSES OF MULTIPHASE FLOW AND HEAT TRANSFER IN UNSATURATED FRACTURED ROCK

    International Nuclear Information System (INIS)

    A mountain-scale, thermal-hydrologic (TH) numerical model is developed for investigating unsaturated flow behavior in response to decay heat from the radioactive waste repository at Yucca Mountain, Nevada, USA. The TH model, consisting of three-dimensional (3-D) representations of the unsaturated zone, is based on the current repository design, drift layout, and thermal loading scenario under estimated current and future climate conditions. More specifically, the TH model implements the current geological framework and hydrogeological conceptual models, and incorporates the most updated, best-estimated input parameters. This mountain-scale TH model simulates the coupled TH processes related to mountain-scale multiphase fluid flow, and evaluates the impact of radioactive waste heat on the hydrogeological system, including thermally perturbed liquid saturation, gas- and liquid-phase fluxes, and water and rock temperature elevations, as well as the changes in water flux driven by evaporation/condensation processes and drainage between drifts. For a better description of the ambient geothermal condition of the unsaturated zone system, the TH model is first calibrated against measured borehole temperature data. The ambient temperature calibration provides the necessary surface and water table boundary as well as initial conditions. Then, the TH model is used to obtain scientific understanding of TH processes in the Yucca Mountain unsaturated zone under the designed schedule of repository thermal load

  18. Effect of rheology on flow displacement during cementing process in oil wells

    Energy Technology Data Exchange (ETDEWEB)

    Braghini, Andre; Naccache, Monica F.; Fonseca, Marcos I. [Dept. Mechanical Engineering. Pontificia Universidade Catolica (PUR-Rio), Rio de Janeiro, RJ (Brazil)], e-mails: mnaccache@puc-rio.br; Miranda, Cristiane R. de; Martins, Andre L.; Aranha, Pedro E. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)], e-mails: crisrichard@petrobras.com.br, aleibsohn@petrobras.com.br, pearanha@petrobras.com.br

    2010-07-01

    This paper describes a set of numerical simulations of the displacement flow of three non-Newtonian fluids through annular eccentric wells. The main application of this work is the studying of drilling and completion processes of oil wells where a cement slurry pushes the drilling mud, used in the drilling process to lubricate the drill and to remove the produced drilling cuts. To avoid contamination, a spacer fluid is usually inserted between them. Both drilling mud and cement slurry behave as non-Newtonian fluids, and the spacer fluid can be Newtonian or non-Newtonian. The analysis of flow and interface configuration between these fluids helps to determine contamination, and is an important tool for the process optimization. The numerical solution of the governing conservation equations of mass and momentum is obtained with the Fluent software, using the finite volume technique and the volume of fluid method. The effects of rheological parameters, density ratios and pumped volume of the spacer fluid are investigated. The results obtained show that the displacement is better when a more viscous spacer fluid is used. The results also show that using lower amounts of the spacer fluid can lead to contamination, which is worse in the smaller gap region of the annular space, in the case of non-rectilinear well. It was also observed that the density ratios play a major role in the cementing operation. (author)

  19. Flow behaviour of magnesium alloy AZ31B processed by equal-channel angular pressing

    Science.gov (United States)

    Arun, M. S.; Chakkingal, U.

    2014-08-01

    Magnesium alloys are characterised by their low density, high specific strength and stiffness. But, the potential application of Mg is limited by its low room-temperature ductility & formability. Formability can be improved by developing an ultrafine grained (UFG) structure. Equal channel angular pressing (ECAP) is a well known process that can be used to develop an ultrafine grained microstructure. The aim of this study was to investigate the flow behaviour of AZ31B magnesium alloy after ECAP. The specimen was subjected to three passes of ECAP with a die angle of 120° using processing route Bc. The processing temperature was 523 K for the first pass and 423 K for the subsequent two passes. The microstructure characterisation was done. Compression tests of ECAPed and annealed specimens were carried out at strain rates of 0.01 - 1s-1 and deformation temperatures of 200 - 300°C using computer servo-controlled Gleeble-3800 system. The value of activation energy Q and the empirical materials constants of A and n were determined. The equations relating flow stress and Zener-Hollomon parameter were proposed. In the case annealed AZ31, the activation energy was determined to be 154 kJ/mol, which was slightly higher than the activation energy of 144 kJ/mol for ECAPed AZ31.

  20. Melting process of packed beds of ice particles by water flow

    International Nuclear Information System (INIS)

    This paper reports on packed beds of ice particles that were submerged in a container and were melted by water flow which was showered in at the top of the container. The container was surrounded by insulator so that the melting process can be assumed as one dimensional problem. To make clear the local melting phenomena, ice layer was divided into several layers. Initial diameter of an ice particle, amount of ice, flow rate of water and inlet water temperature were fixed for each experiment. During the melting process, water temperature among the ice layers and remaining ice mass in each layer were measured. From the experiment, Nusselt number during the melting process was obtained. Experiments in which the ice layer was not divided, were also carried out. In the analysis, timewise changes of outlet water temperature and remaining ice mass were calculated for both types of experiment. The Nusselt number used in the analysis was the one obtained in the experiment. From the analysis and experiments, the time to finish the melting was expressed as a simple function. Analytical results agreed well with the experimental ones

  1. Perirheic mixing and biogeochemical processing in flow-through and backwater floodplain wetlands

    Science.gov (United States)

    Jones, C. Nathan; Scott, Durelle T.; Edwards, Brandon L.; Keim, Richard F.

    2014-09-01

    Inundation hydrology and associated processes control biogeochemical processing in floodplains. To better understand how hydrologic connectivity, residence time, and intrafloodplain mixing vary in floodplain wetlands, we examined how water quality of two contrasting areas in the floodplain of the Atchafalaya River—a flow-through and a backwater wetland—responded to an annual flood pulse. Large, synoptic sampling campaigns occurred in both wetlands during the rising limb, peak, and falling limb of the hydrograph. Using a combination of conservative and reactive tracers, we inferred three dominant processes that occurred over the course of the flood pulse: flushing (rising limb), advective transport (peak), and organic matter accumulation (falling limb). Biogeochemistry of the two wetlands was similar during the peak while the river overflowed into both. However, during the rising and falling limbs, flow in the backwater wetland experienced much greater residence time. This led to the accumulation of dissolved organic matter and dissolved phosphorus. There were also elevated ratios of dissolved organic carbon to nitrate in the backwater wetland, suggesting nitrogen removal was limited by nitrate transported into the floodplain there. Collectively, our results suggest inclusion of a temporal component into the perirheic concept more fully describes inundation hydrology and biogeochemistry in large river floodplain. This article was corrected on 6 OCT 2014. See the end of the full text for details

  2. Impact of polymer film thickness and cavity size on polymer flow during embossing : towards process design rules for nanoimprint lithography.

    Energy Technology Data Exchange (ETDEWEB)

    Schunk, Peter Randall; King, William P. (Georgia Institute of Technology, Atlanta, GA); Sun, Amy Cha-Tien; Rowland, Harry D. (Georgia Institute of Technology, Atlanta, GA)

    2006-08-01

    This paper presents continuum simulations of polymer flow during nanoimprint lithography (NIL). The simulations capture the underlying physics of polymer flow from the nanometer to millimeter length scale and examine geometry and thermophysical process quantities affecting cavity filling. Variations in embossing tool geometry and polymer film thickness during viscous flow distinguish different flow driving mechanisms. Three parameters can predict polymer deformation mode: cavity width to polymer thickness ratio, polymer supply ratio, and Capillary number. The ratio of cavity width to initial polymer film thickness determines vertically or laterally dominant deformation. The ratio of indenter width to residual film thickness measures polymer supply beneath the indenter which determines Stokes or squeeze flow. The local geometry ratios can predict a fill time based on laminar flow between plates, Stokes flow, or squeeze flow. Characteristic NIL capillary number based on geometry-dependent fill time distinguishes between capillary or viscous driven flows. The three parameters predict filling modes observed in published studies of NIL deformation over nanometer to millimeter length scales. The work seeks to establish process design rules for NIL and to provide tools for the rational design of NIL master templates, resist polymers, and process parameters.

  3. A flow-through chromatography process for influenza A and B virus purification.

    Science.gov (United States)

    Weigel, Thomas; Solomaier, Thomas; Peuker, Alessa; Pathapati, Trinath; Wolff, Michael W; Reichl, Udo

    2014-10-01

    Vaccination is still the most efficient measure to protect against influenza virus infections. Besides the seasonal wave of influenza, pandemic outbreaks of bird or swine flu represent a high threat to human population. With the establishment of cell culture-based processes, there is a growing demand for robust, economic and efficient downstream processes for influenza virus purification. This study focused on the development of an economic flow-through chromatographic process avoiding virus strain sensitive capture steps. Therefore, a three-step process consisting of anion exchange chromatography (AEC), Benzonase(®) treatment, and size exclusion chromatography with a ligand-activated core (LCC) was established, and tested for purification of two influenza A virus strains and one influenza B virus strain. The process resulted in high virus yields (?68%) with protein contamination levels fulfilling requirements of the European Pharmacopeia for production of influenza vaccines for human use. DNA was depleted by ?98.7% for all strains. The measured DNA concentrations per dose were close to the required limits of 10ng DNA per dose set by the European Pharmacopeia. In addition, the added Benzonase(®) could be successfully removed from the product fraction. Overall, the presented downstream process could potentially represent a simple, robust and economic platform technology for production of cell culture-derived influenza vaccines. PMID:24992667

  4. Two-Phase Flow in Packed Columns and Generation of Bubbly Suspensions for Chemical Processing in Space

    Science.gov (United States)

    Motil, Brian J.; Green, R. D.; Nahra, H. K.; Sridhar, K. R.

    2000-01-01

    For long-duration space missions, the life support and In-Situ Resource Utilization (ISRU) systems necessary to lower the mass and volume of consumables carried from Earth will require more sophisticated chemical processing technologies involving gas-liquid two-phase flows. This paper discusses some preliminary two-phase flow work in packed columns and generation of bubbly suspensions, two types of flow systems that can exist in a number of chemical processing devices. The experimental hardware for a co-current flow, packed column operated in two ground-based low gravity facilities (two-second drop tower and KC- 135 low-gravity aircraft) is described. The preliminary results of this experimental work are discussed. The flow regimes observed and the conditions under which these flow regimes occur are compared with the available co-current packed column experimental work performed in normal gravity. For bubbly suspensions, the experimental hardware for generation of uniformly sized bubbles in Couette flow in microgravity conditions is described. Experimental work was performed on a number of bubbler designs, and the capillary bubble tube was found to produce the most consistent size bubbles. Low air flow rates and low Couette flow produce consistent 2-3 mm bubbles, the size of interest for the "Behavior of Rapidly Sheared Bubbly Suspension" flight experiment. Finally the mass transfer implications of these two-phase flows is qualitatively discussed.

  5. Towards estimation of extreme floods: examination of the roles of runoff process changes and floodplain flows

    Science.gov (United States)

    Jothityangkoon, Chatchai; Sivapalan, Murugesu

    2003-10-01

    This paper presents the development and application of a distributed rainfall-runoff model for extreme flood estimation, and its use to investigate potential changes in runoff processes, including changes to the 'rating curve' due to effects of over-bank flows, during the transition from 'normal' floods to 'extreme' floods. The model has two components: a hillslope runoff generation model based on a configuration of soil moisture stores in parallel and series, and a distributed flood routing model based on non-linear storage-discharge relationships for individual river reaches that includes the effects of floodplain geometries and roughnesses. The hillslope water balance model contains a number of parameters, which are measured or derived a priori from climate, soil and vegetation data or streamflow recession analyses. For reliable estimation of extreme discharges that may extend beyond recorded data, the parameters of the flood routing model are estimated from hydraulic properties, topographic data and vegetation cover of compound channels (main channel and floodplains). This includes the effects of the interactions between the main channel and floodplain sections, which tend to cause a change to the rating curve. The model is applied to the Collie River Basin, 2545 km 2, in Western Australia and used to estimate the probable maximum flood (PMF) from probable maximum precipitation estimates for this region. When moving from normal floods to the PMFs, application of the model demonstrates that the runoff generation process changes with a substantial increase of saturation excess overland flow through the expansion of saturated areas, and the dominant runoff process in the stream channel changes from in-bank to over-bank flows. The effects of floodplain inundation and floodplain vegetation can significantly reduce the magnitude of the estimated PMFs. This study has highlighted the need for the estimation of a number of critical parameters (e.g. cross-sectional geometry, floodplain vegetation, soil depths) through concerted field measurements or surveys, and targeted laboratory experiments.

  6. An Approach to Code Generation from UML Diagrams

    Directory of Open Access Journals (Sweden)

    Harshal D. Gurad

    2014-01-01

    Full Text Available The Unified Modeling Language (UML has now become the de-facto industry standard for object-oriented (OO software development. UML provides a set of diagrams to model structural and behavioral aspects of an object-oriented system. Automatic translation of UML diagrams to object oriented code is highly desirable because it eliminates the chances of introduction of human errors in the translation process. Automatic code generation is efficient which, in turn, helps the software engineers deliver the software on time. However, major challenges in this area include checking consistency of UML models, and ensuring accuracy, maintainability, and efficiency of the generated code. This paper represents an approach to generate efficient and compact executable code from UML diagram. By analyzing the characteristics UML diagram, a coding strategy is proposed, and a structure identification and coding algorithm are put forward for code generation from UML diagram. Based on the coding strategy an algorithm is proposed to generate code from UML diagrams using some intermediate steps. The main objective of this paper is to generate the code from UML diagram.

  7. Interface flow process audit: using the patient's career as a tracer of quality of care and of system organisation

    Directory of Open Access Journals (Sweden)

    Jean-Pierre Unger

    2004-05-01

    Full Text Available Objectives: This case study aims to demonstrate the method's feasibility and capacity to improve quality of care. Several drawbacks attached to tracer condition and selected procedure audits oblige clinicians to rely on external evaluators. Interface flow process audit is an alternative method, which also favours integration of health care across institutions divide. Methods: An action research study was carried out to test the feasibility of interface flow process audit and its impact on quality improvement. An anonymous questionnaire was carried out to assess the participants' perception of the process. Results: In this study, interface flow process audit brought together general practitioners and hospital doctors to analyse the co-ordination of their activities across the primary-secondary interface. Human factors and organisational characteristics had a clear influence on implementation of the solutions. In general, the participants confirmed that the interface flow process audit helped them to analyse the quality of case management both at primary and secondary care level. Conclusions: The interface flow process audit appears a useful method for regular in-service self-evaluation. Its practice enabled to address a wide scope of clinical, managerial and economical problems. Bridging the primary-secondary care gap, interface flow process audit's focus on the patient's career combined with the broad scope of problems that can be analysed are particularly powerful features. The methodology would benefit from an evaluation of its practice on larger scale.

  8. The resummation of inter-jet energy flow for gaps-between-jets processes at HERA

    International Nuclear Information System (INIS)

    We calculate resummed perturbative predictions for gaps-between-jets processes and compare to HERA data. Our calculation of this non-global observable needs to include the effects of primary gluon emission (global logarithms) and secondary gluon emission (non-global logarithms) to be correct at the leading logarithm (LL) level. We include primary emission by calculating anomalous dimension matrices for the geometry of the specific event definitions and estimate the effect of non-global logarithms in the large Nc limit. The resulting predictions for energy flow observables are consistent with experimental data. (author)

  9. The resummation of inter-jet energy flow for gaps-between-jets processes at HERA

    CERN Document Server

    Appleby, R B

    2003-01-01

    We calculate resummed perturbative predictions for gaps-between-jets processes and compare to HERA data. Our calculation of this non-global observable needs to include the effects of primary gluon emission (global logarithms) and secondary gluon emission (non-global logarithms) to be correct at the leading logarithm (LL) level. We include primary emission by calculating anomalous dimension matrices for the geometry of the specific event definitions and estimate the effect of non-global logarithms in the large $N_c$ limit. The resulting predictions for energy flow observables are consistant with experimental data.

  10. Chemical and biological processes in fluid flows a dynamical systems approach

    CERN Document Server

    Neufeld, Zoltán

    2009-01-01

    Many chemical and biological processes take place in fluid environments in constant motion - chemical reactions in the atmosphere, biological population dynamics in the ocean, chemical reactors, combustion, and microfluidic devices. Applications of concepts from the field of nonlinear dynamical systems have led to significant progress over the last decade in the theoretical understanding of complex phenomena observed in such systems. This book introduces the theoretical approaches for describing mixing and transport in fluid flows. It reviews the basic concepts of dynamical phenomena arising f

  11. Bosonic Loop Diagrams as Perturbative Solutions of the Classical Field Equations in ?4-Theory

    International Nuclear Information System (INIS)

    Solutions of the classical ?4-theory in Minkowski space-time are analyzed in a perturbation expansion in the nonlinearity. Using the language of Feynman diagrams, the solution of the Cauchy problem is expressed in terms of tree diagrams which involve the retarded Green's function and have one outgoing leg. In order to obtain general tree diagrams, we set up a ''classical measurement process'' in which a virtual observer of a scattering experiment modifies the field and detects suitable energy differences. By adding a classical stochastic background field, we even obtain all loop diagrams. The expansions are compared with the standard Feynman diagrams of the corresponding quantum field theory.

  12. Particle velocity fields and depositional processes in laboratory ash flows, with implications for the sedimentation of dense pyroclastic flows

    Science.gov (United States)

    Girolami, L.; Roche, O.; Druitt, T. H.; Corpetti, T.

    2010-08-01

    We conducted laboratory experiments on dam-break flows of sub-250-µm volcanic ash, generated by the release of gas-fluidized and variably non-expanded to expanded (up to 35%) beds, in order to gain insights into the internal kinematics of pyroclastic flows. The flows were typically several cm thick and had frontal speeds of up to ˜2 m s-1. High-speed videos taken through the transparent sidewall of the 3-m-long channel were analyzed with a particle-tracking algorithm, providing a spatial and temporal description of transport and sedimentation. The flows deposited progressively as they traveled down the flume, being consumed by sedimentation until they ran out of volume. Deposition commenced 5-20 cm rearward of the flow front and (for a given expansion) proceeded at a rate independent of distance from the lock gate. Deposit aggradation velocities were equal to those inferred beneath quasi-static bed collapse tests of the same ash at the same initial expansions, implying that shear rates of up to ˜300 s-1 have no measurable effect on aggradation rate. The initially non-expanded (and just fluidized) flow deposited progressively at a rate indicative of an expansion of a few percent, perhaps due to shear-induced Reynolds dilation during initial slumping. The fronts of the flows slid across the flume floor on very thin basal shear layers, but once deposition commenced a no-slip condition was established at the depositional interface. Within the flows, the trajectory of the constituent particles was linear and sub-horizontal. The velocities of the particles increased with height above the depositional interface, reached a maximum, then declined slightly towards the flow surface, perhaps due to air drag. At a given location, the velocity profiles were translated upwards as the deposit aggraded. The results show that even cm-thin, poorly expanded flows of ash deposit progressively, as inferred for many pyroclastic flows. The change from (frontal) slip to (rearward) no-slip conditions at the bases of the laboratory flows are qualitatively consistent with some textural features of pyroclastic flow deposits.

  13. Determination of sulfate in the wet-process of phosphoric acid by reverse flow injection

    Scientific Electronic Library Online (English)

    Wenhui, Shi; Lin, Yang; Quanjun, Fu; Zhiye, Zhang; Xinlong, Wang.

    1357-13-01

    Full Text Available SciELO Brazil | Language: English Abstract in english An improved method based on reverse flow injection is proposed for determining sulfate concentration in the wet-process of phosphoric acid (WPA). The effect of reagent composition, flow rate, temperature, acid concentration, length of the reaction coil, and linear response range on the flow system i [...] s discussed in detail. Optimal conditions are established for determining sulfate in the WPA samples. Baseline drift is avoided by a periodic washing step with EDTA in an alkaline medium. A linear response is observed within a range of 20 - 360 mg L-1, given by the equation A = 0.0020C (mg L-1) + 0.0300, R² = 0.9991. The detection limit of the proposed method for sulfate analysis is 3 mg L-1, and the relative standard deviation (n = 12) of sulfate absorbance peak is less than 1.60%. This method has a rate of up to 29 samples per hour, and the results compare well with those obtained with gravimetric method.

  14. Interface flow process audit: using the patient's career as a tracer of care and of system organisation

    OpenAIRE

    Unger, J. P.; Marchal, B.; Dugas, S.; Wuidar, M. J.; Burdet, D.; Leemans, P.; Unger, J.

    2004-01-01

    OBJECTIVES: This case study aims to demonstrate the method's feasibility and capacity to improve quality of care. Several drawbacks attached to tracer condition and selected procedure audits oblige clinicians to rely on external evaluators. Interface flow process audit is an alternative method, which also favours integration of health care across institutions divide. METHODS: An action research study was carried out to test the feasibility of interface flow process audit and its impact on qua...

  15. Interface flow process audit: using the patient's career as a tracer of quality of care and of system organisation

    OpenAIRE

    Jean-Pierre Unger; Bruno Marchal; Sylvie Dugas; Marie-Jeanne Wuidar; Daniel Burdet; Pierre Leemans; Jacques Unger

    2004-01-01

    Objectives: This case study aims to demonstrate the method's feasibility and capacity to improve quality of care. Several drawbacks attached to tracer condition and selected procedure audits oblige clinicians to rely on external evaluators. Interface flow process audit is an alternative method, which also favours integration of health care across institutions divide. Methods: An action research study was carried out to test the feasibility of interface flow process audit and its impact on qua...

  16. Conservação e reúso de águas usando o método Diagrama de Fontes de Água para processos em batelada: estudo de casos / Water conservation and reuse using the Water Sources Diagram method for batch process: case studies

    Scientific Electronic Library Online (English)

    Reinaldo Coelho, Mirre; Shaula Christine Leal, Ferreira; Aline Rodrigues, Dias; Fernando Luiz Pellegrini, Pessoa.

    2012-03-01

    Full Text Available O gerenciamento de recursos hídricos tem sido um fator importante para a sustentabilidade dos processos industriais, visto que há uma necessidade crescente pelo desenvolvimento de metodologias voltadas para conservação e uso racional da água. O objetivo deste trabalho foi aplicar o método Diagrama d [...] e Fontes de Água (DFA), usado na definição de metas de mínimo consumo de água, a processos que operam em regime batelada. Foram gerados e avaliados cenários de reúso de correntes obtidos pela aplicação do método a partir de dados de quantidade de água e concentração de contaminantes nas operações. Foram apresentados dois estudos de caso com o objetivo de demonstrar a redução de consumo de água e da geração de efluentes, além de custos de tratamento final e de investimento em tanques de estocagem, em relação à configuração inicial. Os cenários mostraram-se bastante promissores, com reduções que alcançam 45%, em termos de consumo hídrico e geração de efluentes, e 37%, em termos de custos de tanques, sem a necessidade de processos de regeneração. Com isso, a técnica empregada mostrou-se relevante e flexível como alternativa às ferramentas sistemáticas voltadas para a minimização do consumo de água em processos industriais, exercendo importante papel em um programa de gerenciamento de recursos hídricos. Abstract in english The water resources management has been an important factor for the sustainability of industrial processes, since there is a growing need for the development of methodologies aimed at the conservation and rational use of water. The objective of this work was to apply the heuristic-algorithmic method [...] called Water Sources Diagram (WSD), which is used to define the target of minimum water consumption, to batch processes. Scenarios with reuse of streams were generated and evaluated with application of the method from the data of water quantity and concentration of contaminants in the operations. Two case studies aiming to show the reduction of water consumption and wastewater generation, and final treatment costs besides investment in storage tanks, were presented. The scenarios showed great promising, achieving reduction up to 45% in water consumption and wastewater generation, and a reduction of around 37% on cost of storage tanks, without the need to allocate regeneration processes. Thus, the WSD method showed to be a relevant and flexible alternative regarding to systemic tools aimed at minimizing the consumption of water in industrial processes, playing an important role within a program of water resources management.

  17. Streamline topology and dilute particle dynamics in a Karman vortex street flow

    OpenAIRE

    Wu, Zuo-bing

    2004-01-01

    Three types of streamline topology in a Karman vortex street flow are shown under the variation of spatial parameters. For the motion of dilute particles in the K\\'arm\\'an vortex street flow, there exist a route of bifurcation to a chaotic orbit and more attractors in a bifurcation diagram for the proportion of particle density to fluid density. Along with the increase of spatial parameters in the flow filed, the bifurcation process is suspended, as well as more and more att...

  18. Modeling unsaturated zone flow and runoff processes by integrating MODFLOW-LGR and VSF, and creating the new CFL package

    Science.gov (United States)

    Borsi, I.; Rossetto, R.; Schifani, C.; Hill, M. C.

    2013-04-01

    SummaryIn this paper two modifications to the MODFLOW code are presented. One concerns an extension of Local Grid Refinement (LGR) to Variable Saturated Flow process (VSF) capability. This modification allows the user to solve the 3D Richards' equation only in selected parts of the model domain. The second modification introduces a new package, named CFL (Cascading Flow), which improves the computation of overland flow when ground surface saturation is simulated using either VSF or the Unsaturated Zone Flow (UZF) package. The modeling concepts are presented and demonstrated. Programmer documentation is included in appendices.

  19. Cut Diagrams for High Energy Scatterings

    OpenAIRE

    Feng, Y. J.; Hamidi-ravari, O.; Lam, C. S.

    1996-01-01

    A new approach is introduced to study QCD amplitudes at high energy and comparatively small momentum transfer. Novel cut diagrams, representing resummation of Feynman diagrams, are used to simplify calculation and to avoid delicate cancellations encountered in the usual approach. Explicit calculation to the 6th order is carried out to demonstrate the advantage of cut diagrams over Feynman diagrams.

  20. Cut diagrams for high energy scatterings

    CERN Document Server

    Feng, Y J; Lam, C S

    1996-01-01

    A new approach is introduced to study QCD amplitudes at high energy and comparatively small momentum transfer. Novel cut diagrams, representing resummation of Feynman diagrams, are used to simplify calculation and to avoid delicate cancellations encountered in the usual approach. Explicit calculation to the 6th order is carried out to demonstrate the advantage of cut diagrams over Feynman diagrams.

  1. Effects of flow scarcity on leaf-litter processing under oceanic climate conditions in calcareous streams.

    Science.gov (United States)

    Martínez, Aingeru; Pérez, Javier; Molinero, Jon; Sagarduy, Mikel; Pozo, Jesús

    2015-01-15

    Although temporary streams represent a high proportion of the total number and length of running waters, historically the study of intermittent streams has received less attention than that of perennial ones. The goal of the present study was to assess the effects of flow cessation on litter decomposition in calcareous streams under oceanic climate conditions. For this, leaf litter of alder was incubated in four streams (S1, S2, S3 and S4) with different flow regimes (S3 and S4 with zero-flow periods) from northern Spain. To distinguish the relative importance and contribution of decomposers and detritivores, fine- and coarse-mesh litter bags were used. We determined processing rates, leaf-C, -N and -P concentrations, invertebrate colonization in coarse bags and benthic invertebrates. Decomposition rates in fine bags were similar among streams. In coarse bags, only one of the intermittent streams, S4, showed a lower rate than that in the other ones as a consequence of lower invertebrate colonization. The material incubated in fine bags presented higher leaf-N and -P concentrations than those in the coarse ones, except in S4, pointing out that the decomposition in this stream was driven mainly by microorganisms. Benthic macroinvertebrate and shredder density and biomass were lower in intermittent streams than those in perennial ones. However, the bags in S3 presented a greater amount of total macroinvertebrates and shredders comparing with the benthos. The most suitable explanation is that the fauna find a food substrate in bags less affected by calcite precipitation, which is common in the streambed at this site. Decomposition rate in coarse bags was positively related to associated shredder biomass. Thus, droughts in streams under oceanic climate conditions affect mainly the macroinvertebrate detritivore activity, although macroinvertebrates may show distinct behavior imposed by the physicochemical properties of water, mainly travertine precipitation, which can override the flow intermittence effects. PMID:24962591

  2. Removal of paraquat and linuron from water by continuous flow adsorption/ ultrafiltration membrane processes

    International Nuclear Information System (INIS)

    The magnetic activated carbon (MAC) was prepared, characterized and compared with powdered activated carbon (PAC) for its adsorptive parameters. Both adsorbents were then used in combination ultrafiltration (UF) membrane as pretreatment for the removal of paraquat and linuron from water. The comparison of membrane parameters like percent retention, permeate flux and backwash times for PAC/UF and MAC/UF hybrid processes showed that percent retention of paraquat and linuron was high for PAC due to its high surface area. However due to cake formation over membrane surface the decline permeate fluxes and long backwash times for PAC were observed. PAC also caused blackening of pipes and flow meter. MAC (an iron oxide and PAC composite) was removed from slurry through magnet thus no cake formation and secondary problems observed for PAC was not encountered. Also the backwash times were minimum for MAC/UF process. (author)

  3. A work process and information flow description of control room operations

    International Nuclear Information System (INIS)

    The control room workplace is the location from which all plant operations are supervised and controlled on a shift-to-shift basis. The activities comprising plant operations are structured into a number of work processes, and information is the common currency that is used to convey work requirements, communicate business and operating decisions, specify work practice, and describe the ongoing plant and work status. This paper describes the motivation for and early experience with developing a work process and information flow model of CANDU control room operations, and discusses some of the insights developed from model examination that suggest ways in which changes in control centre work specification, organization of resources, or asset layout could be undertaken to achieve operational improvements. (author)

  4. Evaluating the flow processes in ultrafine-grained materials at elevated temperatures

    Scientific Electronic Library Online (English)

    Megumi, Kawasaki; Terence G., Langdon.

    2013-06-01

    Full Text Available When polycrystalline materials are tested in tension at elevated temperatures, the flow mechanisms depend upon various parameters including the temperature of testing, the applied stress and the material grain size. The plotting of deformation mechanism maps is a procedure used widely in displaying [...] and interpreting the creep properties of conventional coarse-grained metals but there have been few attempts to date to use this same procedure for ultrafine-grained and nanocrystalline materials produced through the application of severe plastic deformation (SPD). This report examines the potential for using deformation mechanism mapping for materials processed by SPD and presents examples for materials processed using equal-channel angular pressing and high-pressure torsion.

  5. Comparison of advanced oxidation processes in flow-through pilot plants (part I).

    Science.gov (United States)

    Muller, J P; Jekel, M

    2001-01-01

    The advanced oxidation processes (AOPs) UV/H2O2, UV/O3 and O3/H2O2 were optimised to achieve a 90% degradation of the micropollutant atrazine in continuous-flow reactors. The experiments were performed with spiked Berlin tap-water. The comparison of mechanistically different oxidation systems needs a non-specific figure-of-merit to avoid influences by system-inherent parameters. The chosen figure-of-merit consists of the electrical energy per order of magnitude in oxidation per m3, EE/o. The combination O3/H2O2 proved to be the most efficient process by means of energy consumption. PMID:11695474

  6. Particle methods for simulation of subsurface multiphase fluid flow and biogeochemical processes

    Energy Technology Data Exchange (ETDEWEB)

    Meakin, Paul [Idaho National Laboratory (United States); Tartakovsky, Alexandre [Pacific Northwest National Laboratory (United States); Scheibe, Tim [Pacific Northwest National Laboratory (United States); Tartakovsky, Daniel [University of California, San Diego (United States); Redden, George [Idaho National Laboratory (United States); Long, Philip E [Pacific Northwest National Laboratory (United States); Brooks, Scott C [Oak Ridge National Laboratory (United States); Xu Zhijie [Idaho National Laboratory (United States)

    2007-07-15

    A number of particle models that are suitable for simulating multiphase fluid flow and biogeochemical processes have been developed during the last few decades. Here we discuss three of them: a microscopic model - molecular dynamics; a mesoscopic model - dissipative particle dynamics; and a macroscopic model - smoothed particle hydrodynamics. Particle methods are robust and versatile, and it is relatively easy to add additional physical, chemical and biological processes into particle codes. However, the computational efficiency of particle methods is low relative to continuum methods. Multiscale particle methods and hybrid (particle-particle and particle-continuum) methods are needed to improve computational efficiency and make effective use of emerging computational capabilities. These new methods are under development.

  7. Performance Analysis Of Various Anti-Reset Windup Algorithms For A Flow Process Station

    Directory of Open Access Journals (Sweden)

    Shaunak Chakrabartty

    2014-05-01

    Full Text Available The study was aimed to develop the various aspects of Anti reset windup or Integral windup and also the different algorithms available to eliminate the phenomenon of windup. Different open loop responses were obtained from a Flow process Station using MATLAB and SIMULINK and VI Microsystems process control software. The open loop responses were evaluated and different system models were generated using the two point method. The system models were found to follow a decreasing order of Gain values and an increasing order of Td and T values. A SIMULINK model was obtained to implement Back calculation combined with Conditional Integration. The models for the system obtained were simulated using the SIMULINK model and a PID controller and the closed loop responses were generated. The closed loop responses using a PID controller with Back calculation and Conditional integration were found to follow the set point as expected.

  8. Evaluating the flow processes in ultrafine-grained materials at elevated temperatures

    Directory of Open Access Journals (Sweden)

    Megumi Kawasaki

    2013-06-01

    Full Text Available When polycrystalline materials are tested in tension at elevated temperatures, the flow mechanisms depend upon various parameters including the temperature of testing, the applied stress and the material grain size. The plotting of deformation mechanism maps is a procedure used widely in displaying and interpreting the creep properties of conventional coarse-grained metals but there have been few attempts to date to use this same procedure for ultrafine-grained and nanocrystalline materials produced through the application of severe plastic deformation (SPD. This report examines the potential for using deformation mechanism mapping for materials processed by SPD and presents examples for materials processed using equal-channel angular pressing and high-pressure torsion.

  9. A Study on Process Description Method for DFM Using Ontology

    OpenAIRE

    Hiekata, K.; Yamato, H.

    2009-01-01

    A method to describe process and knowledge based on RDF which is an ontology description language and IDEF0 which is a formal process description format is proposed. Once knowledge of experienced engineers is embedded into the system the knowledge will be lost in the future. A production process is described in a proposed format similar to BOM and the process can be retrieved as a flow diagram to make the engineers to understand the product and process. Proposed method is applied ...

  10. Use of the GranuFlow Process in Coal Preparation Plants to Improve Energy Recovery and Reduce Coal Processing Wastes

    Energy Technology Data Exchange (ETDEWEB)

    Glenn A. Shirey; David J. Akers

    2005-12-31

    With the increasing use of screen-bowl centrifuges in today's fine coal cleaning circuits, a significant amount of low-ash, high-Btu coal can be lost during the dewatering step due to the difficulty in capturing coal of this size consist (< 100 mesh or 0.15mm). The GranuFlow{trademark} technology, developed and patented by an in-house research group at DOE-NETL, involves the addition of an emulsified mixture of high-molecular-weight hydrocarbons to a slurry of finesized coal before cleaning and/or mechanical dewatering. The binder selectively agglomerates the coal, but not the clays or other mineral matter. In practice, the binder is applied so as to contact the finest possible size fraction first (for example, froth flotation product) as agglomeration of this fraction produces the best result for a given concentration of binder. Increasing the size consist of the fine-sized coal stream reduces the loss of coal solids to the waste effluent streams from the screen bowl centrifuge circuit. In addition, the agglomerated coal dewaters better and is less dusty. The binder can also serve as a flotation conditioner and may provide freeze protection. The overall objective of the project is to generate all necessary information and data required to commercialize the GranuFlow{trademark} Technology. The technology was evaluated under full-scale operating conditions at three commercial coal preparation plants to determine operating performance and economics. The handling, storage, and combustion properties of the coal produced by this process were compared to untreated coal during a power plant combustion test.

  11. Summary of applications of TOUGH2 to the evaluation of multiphase flow processes at the WIPP

    International Nuclear Information System (INIS)

    The Waste Isolation Pilot Plant (WIPP) is a US Department of Energy (DOE) research and development facility for the underground disposal of transuranic waste in southeastern New Mexico. The WIPP repository is located 655 m below the land surface in the lower portion of the Salado Formation, which is comprised of beds of pure and impure halite with thin interbeds of anhydrite and related clay seams. The regional dip of the Salado Formation is approximately 1 degree southeast in the vicinity of the repository. The proposed waste storage area has eight waste disposal panels, each of which will contain seven rooms. The repository is designed to follow a single stratigraphic horizon. Due to the dip, the north end of the repository will be about 10 meters higher than the south end. Waste that is emplaced in the disposal rooms will generate gas due to microbial degradation, anoxic corrosion, and radiolysis. Brine inflow to the rooms from the surrounding Salado Formation may significantly influence the gas generation rate and the total amount of gas generated. The salt surrounding the repository will creep in response to the excavation, reducing the room volume. Gas generation in the room may increase the pressure sufficiently to drive brine and gas into the surrounding Salado Formation. Migration of gas and brine in the Salado is an important factor in evaluating the performance of the repository. The studies summarized in this paper have. been performed to evaluate brine and gas flow processes in the WIPP disposal system and to identify some of the important processes. These studies are done in support of, but are not part of, the formal Performance Assessment (PA) effort. Because of probabilistic and system-scale requirements, the PA effort uses the Sandia-developed BRAGFLO (BRine And Gas FLOw) code for multiphase flow calculations

  12. Toxic metals in WEEE: characterization and substance flow analysis in waste treatment processes.

    Science.gov (United States)

    Oguchi, Masahiro; Sakanakura, Hirofumi; Terazono, Atsushi

    2013-10-01

    Waste electrical and electronic equipment (WEEE) has received extensive attention as a secondary source of metals. Because WEEE also contains toxic substances such as heavy metals, appropriate management of these substances is important in the recycling and treatment of WEEE. As a basis for discussion toward better management of WEEE, this study characterizes various types of WEEE in terms of toxic metal contents. The fate of various metals contained in WEEE, including toxic metals, was also investigated in actual waste treatment processes. Cathode-ray tube televisions showed the highest concentration and the largest total amount of toxic metals such as Ba, Pb, and Sb, so appropriate recycling and disposal of these televisions would greatly contribute to better management of toxic metals in WEEE. A future challenge is the management of toxic metals in mid-sized items such as audio/visual and ICT equipment because even though the concentrations were not high in these items, the total amount of toxic metals contained in them is not negligible. In the case of Japan, such mid-sized WEEE items as well as small electronic items are subject to municipal solid waste treatment. A case study showed that a landfill was the main destination of toxic metals contained in those items in the current treatment systems. The case study also showed that changes in the flows of toxic metals will occur when treatment processes are modified to emphasize resource recovery. Because the flow changes might lead to an increase in the amount of toxic metals released to the environment, the flows of toxic metals and the materials targeted for resource recovery should be considered simultaneously. PMID:22921510

  13. Low-frequency components and modulation processes in compressible cavity flows

    Science.gov (United States)

    Delprat, N.

    2010-10-01

    The modulated character of cavity-flow oscillations is investigated through a so-called modulation analysis of spectral distributions. The approach is based on a recently proposed viewpoint on the Rossiter formula and concerns mid- to high-subsonic flows in shallow cavities. For this type of configuration, the spectra are mainly characterized by the presence of several dominant peaks (Rossiter modes) that are not in a harmonic relation but uniformly spaced at a distance equal to the fundamental frequency of the oscillation mechanism (aero-acoustic feedback loop). This feature is interpreted as the result of an amplitude modulation process and related to variations in the vortex-corner interaction in the downstream part of the cavity ( ? modulation). A lower frequency modulation is identified through the secondary peak distribution. A detailed analysis of the spectral structure confirms the presence of a component at the corresponding frequency value ( ?f mode). The assumption of a specific coupling between the two modulation processes is investigated. It leads to a new approximate form for the ?-modulation ratio that allows an explicit expression of the Rossiter constant ? related to aspect ratio of the cavity ( L/D).

  14. Deterministic flows of order-parameters in stochastic processes of quantum Monte Carlo method

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Jun-ichi, E-mail: j_inoue@complex.eng.hokudai.ac.j [Complex Systems Engineering, Graduate School of Information Science and Technology, Hokkaido University, N14-W9, Kita-ku, Sapporo 060-0814 (Japan)

    2010-06-01

    In terms of the stochastic process of quantum-mechanical version of Markov chain Monte Carlo method (the MCMC), we analytically derive macroscopically deterministic flow equations of order parameters such as spontaneous magnetization in infinite-range (d(= {infinity})-dimensional) quantum spin systems. By means of the Trotter decomposition, we consider the transition probability of Glauber-type dynamics of microscopic states for the corresponding (d + 1)-dimensional classical system. Under the static approximation, differential equations with respect to macroscopic order parameters are explicitly obtained from the master equation that describes the microscopic-law. In the steady state, we show that the equations are identical to the saddle point equations for the equilibrium state of the same system. The equation for the dynamical Ising model is recovered in the classical limit. We also check the validity of the static approximation by making use of computer simulations for finite size systems and discuss several possible extensions of our approach to disordered spin systems for statistical-mechanical informatics. Especially, we shall use our procedure to evaluate the decoding process of Bayesian image restoration. With the assistance of the concept of dynamical replica theory (the DRT), we derive the zero-temperature flow equation of image restoration measure showing some 'non-monotonic' behaviour in its time evolution.

  15. Modeling of reverse flow partial oxidation process for gasifier product gas upgrading

    Energy Technology Data Exchange (ETDEWEB)

    Tuna, P.; Svensson, H.; Brandin, J. [Lund Univ., Lund (Sweden). Dept. of Chemical Engineering

    2010-07-01

    Second generation biofuels use non-food crops such as agriculture waste and forest residue for the production of fuels. Biomass gasification is an important process for utilization of cellulose rich biomass. The gas produced in gasification contains carbon monoxide (CO), hydrogen (H{sub 2}), water (H{sub 2}O), carbon dioxide (CO{sub 2}), light hydrocarbons and tars. The light hydrocarbons can contain as much as 50 per cent of the total energy contents in the gas, depending on the type of gasifier, the operating conditions and the fuel. The gas also contains catalyst poisons such as sulfur, as hydrogen sulfide (H{sub 2}S) and carbonyl sulfide (COS). This paper presented simulation work of a reverse flow partial oxidation reformer that reaches efficiencies approaching conventional catalytic processes. The study also investigated different reactor designs and parameter variations, such as pressure. Natural gas simulations were provided for comparative evaluations. They demonstrated the benefits of using reverse flow operation with lean gases such as gasifier product gas. 14 refs., 2 tabs., 7 figs.

  16. Flow equation for porous plug and capillary tube flow restrictors

    Science.gov (United States)

    Davis, W. S.

    1972-01-01

    Development of flow measuring apparatus for determining low flow performance of resistojet thruster is discussed. Diagram of test equipment is presented. Operation of test equipment is described and numerical relationships are explained.

  17. Spatial Density Voronoi Diagram and Construction

    Directory of Open Access Journals (Sweden)

    Ye Zhao

    2012-08-01

    Full Text Available To fill a theory gap of Voronoi diagrams that there have been no reports of extended diagrams in spatial density so far. A new concept of spatial density Voronoi diagram was proposed. An important property was presented and proven. And a construction algorithm was presented. Spatial density can be used to indicate factors related to density such as conveyance and the traffic conditions. Some properties of spatial density Voronoi diagram were also introduced. In accordance with discrete construction method, achieved the construction of spatial density Voronoi diagram. Spatial density Voronoi diagram is a developed Voronoi diagram, and planar ordinary Voronoi diagram can be regarded as its special cases. It both perfected the theory about Voronoi diagrams, and extended the range of applications of Voronoi diagrams.

  18. Wafer-scale process and materials optimization in cross-flow atomic layer deposition

    Science.gov (United States)

    Lecordier, Laurent Christophe

    The exceptional thickness control (atomic scale) and conformality (uniformity over nanoscale 3D features) of atomic layer deposition (ALD) has made it the process of choice for numerous applications from microelectronics to nanotechnology, and for a wide variety of ALD processes and resulting materials. While its benefits derive from self-terminated chemisorbed reactions of alternatively supplied gas precursors, identifying a suitable process window in which ALD's benefits are realized can be a challenge, even in favorable cases. In this work, a strategy exploiting in-situ gas phase sensing in conjunction with ex-situ measurements of the film properties at the wafer scale is employed to explore and optimize the prototypical Al2O3 ALD process. Downstream mass-spectrometry is first used to rapidly identify across the [H2O x Al(CH3)3] process space the exposure conditions leading to surface saturation. The impact of precursor doses outside as well as inside the parameter space outlined by mass-spectrometry is then investigated by characterizing film properties across 100 mm wafer using spectroscopic ellipsometry, CV and IV electrical characterization, XPS and SIMS. Under ideal dose conditions, excellent thickness uniformity was achieved (1sigma/meansurface. Since adsorbed species are reactive with respect to subsequent dose of the complementary precursor, such depletion magnifies non-uniformities as seen in the cross-flow reactor, thereby decorating deviations from a suitable ALD process recipe. Degradation of the permittivity and leakage current density across the wafer was observed though the film composition remained unchanged. Upon higher water dose in the over-exposure regime, deposition rates increased by up to 40% while the uniformity degraded. In contrast, overdosing of TMA and ozone (used for comparison to water) did not affect the process performances. These results point to complex saturation dynamics of water dependent on partial pressure and potential multilayer adsorption caused by hydrogen-bonding.

  19. Correlation potential and ladder diagrams

    CERN Document Server

    Dzuba, V A

    2008-01-01

    The all-order correlation potential method of accurate atomic structure calculations for atoms with one external electron is extended to include one more class of correlation diagrams to all orders. These are the so-called ladder diagrams which describe residual Coulomb interaction between an external electron and atomic core. This is in addition to the screening of Coulomb interaction by core electrons and the hole-particle interaction in the core polarization operator which are also included in all orders. Calculations of the energies of the lowest $s$, $p$ and $d$ states of cesium and thallium show that inclusion of the ladder diagrams leads to significant improvement of the accuracy of the calculations. The discrepancy between theoretical and experimental energies is reduced to a small fraction of a per cent in all cases. This widens the range of atoms and atomic states for which the correlation potential method can produce very accurate results.

  20. Estimated International Energy Flows 2007

    Science.gov (United States)

    Clara Smith

    This Energy Flow Charts website is a set of energy Sankey diagrams or flow charts for 136 countries constructed from data maintained by the International Energy Agency (IEA) and reflects the energy use patterns for 2007.

  1. Simulations for parallel processing of ultrasound reflection-mode tomography with applications to two-phase flow measurement

    Science.gov (United States)

    Wiegand, Frank; Hoyle, Brian S.

    1989-11-01

    An evaluation of the application of a parallel-processing array to the measurement of two-phase flow, such as bubbly oil flow through a pipe, in real-time is described. Pulse-echo ultrasound tomography is used to generate a cross-sectional image of the flow that forms the basis for the deduction of flow parameters, such as the void fraction. The tomographic algorithm used here is backprojection adapted for execution on an array of parallel-processing devices. It is shown that real-time reconstruction is feasible using the concepts of parallel processing. Different sensor arrangements were investigated by computer simulation. It is shown that a special multisegment sensor results in a significant improvement in signal-to-noise ratio and image quality and that the reconstructed image benefits from the concurrent activation of multiple receivers per transmitted pulse. The findings may also be useful for nondestructive testing and medical applications.

  2. Process for continually placing an atmosphere in close circuit flow and its application to a reprocessing plant

    International Nuclear Information System (INIS)

    This invention concerns the plant and chemical processes and in particular a plant and processes where the atmosphere is contained and continually placed in close circuit flow. Such a plant can be used for processes where the atmosphere of the plant must be prevented from going outside, such as in the case of a plant processing nuclear fuel, like a plant in which irradiated nuclear fuels are reprocessed or in which fuels containing plutonium are made

  3. Integrated Water Flow Model (IWFM), A Tool For Numerically Simulating Linked Groundwater, Surface Water And Land-Surface Hydrologic Processes

    Science.gov (United States)

    Dogrul, E. C.; Brush, C. F.; Kadir, T. N.

    2006-12-01

    The Integrated Water Flow Model (IWFM) is a comprehensive input-driven application for simulating groundwater flow, surface water flow and land-surface hydrologic processes, and interactions between these processes, developed by the California Department of Water Resources (DWR). IWFM couples a 3-D finite element groundwater flow process and 1-D land surface, lake, stream flow and vertical unsaturated-zone flow processes which are solved simultaneously at each time step. The groundwater flow system is simulated as a multilayer aquifer system with a mixture of confined and unconfined aquifers separated by semiconfining layers. The groundwater flow process can simulate changing aquifer conditions (confined to unconfined and vice versa), subsidence, tile drains, injection wells and pumping wells. The land surface process calculates elemental water budgets for agricultural, urban, riparian and native vegetation classes. Crop water demands are dynamically calculated using distributed soil properties, land use and crop data, and precipitation and evapotranspiration rates. The crop mix can also be automatically modified as a function of pumping lift using logit functions. Surface water diversions and groundwater pumping can each be specified, or can be automatically adjusted at run time to balance water supply with water demand. The land-surface process also routes runoff to streams and deep percolation to the unsaturated zone. Surface water networks are specified as a series of stream nodes (coincident with groundwater nodes) with specified bed elevation, conductance and stage-flow relationships. Stream nodes are linked to form stream reaches. Stream inflows at the model boundary, surface water diversion locations, and one or more surface water deliveries per location are specified. IWFM routes stream flows through the network, calculating groundwater-surface water interactions, accumulating inflows from runoff, and allocating available stream flows to meet specified or calculated deliveries. IWFM utilizes a very straight-forward input file structure, allowing rapid development of complex simulations. A key feature of IWFM is a new algorithm for computation of groundwater flow across element faces. Enhancements to version 3.0 include automatic time-tracking of input and output data sets, linkage with the HEC-DSS database, and dynamic crop allocation using logit functions. Utilities linking IWFM to the PEST automated calibration suite are also available. All source code, executables and documentation are available for download from the DWR web site. IWFM is currently being used to develop hydrologic simulations of California's Central Valley (C2VSIM); the west side of California's San Joaquin Valley (WESTSIM); Butte County, CA; Solano County, CA; Merced County, CA; and the Oregon side of the Walla Walla River Basin.

  4. Pilot results for a revolutionary cross-flow, fluid bed upgrading process

    Energy Technology Data Exchange (ETDEWEB)

    Lesage, B.; Monaghan, G.; Brown, W.A. [ETX Systems Inc., Calgary, AB (Canada)

    2009-07-01

    The I{sup Y}Q Upgrading technology developed by Calgary-based ETX Systems Inc. merges 2 commercial technologies, notably cross flow fluid beds and thermal processing of heavy oil on fluid beds. The process has much lower commercialization risks than technologies based on more step-outs. ETX Systems conducted a pilot scale demonstration of its proprietary process as part of its commercialization strategy. A 1 bbl/d hot pilot plant was constructed in 2006 at the National Centre for Upgrading Technology in Devon, Alberta to verify the yield and quality claims of the I{sup Y}Q Upgrading technology. Although the results from the pilot project fully supported ETX's yield and quality claims, challenges were encountered with the pilot plant operation because of the small scale of the demonstration exercise. Through a targeted troubleshooting program, performance of the pilot unit was gradually increased to the point where it could accept pitch feed, as intended. This paper summarized the challenges encountered in the pilot program. To date, over 140 runs have been completed in the pilot unit. The pilot work supports the original claims regarding increased hydrogen retention in the product liquids, resulting in a significant environmental benefit through a reduction in upstream and downstream processing, thereby reducing intensities on a lifecycle basis. 4 refs., 2 tabs., 6 figs.

  5. Transformation of BPMN Diagrams to YAWL Nets

    Directory of Open Access Journals (Sweden)

    Jianhong Ye

    2010-04-01

    Full Text Available Business Process Modeling Notation (BPMN is the de facto standard for modeling business processes on a conceptual level. However, BPMN lacks a formal semantics and many of its features need to be further interpret, Consequently that hinders  BPMN as a standard to statically check the semantic correctness of models. YAWL (Yet Another Workflow Language allows the specification of executable workflow models. A transformation between these two languages enables the integration of different levels of abstraction in process modeling. This paper discusses how to transform BPMN diagrams to YAWL nets. The benefits of the transformation are threefold. Firstly, it clarifies the semantics of BPMN via a mapping to YAWL. Secondly, the deployment of BPMN business process models is simplified. Thirdly, BPMN models can be analyzed with YAWL verification tools.

  6. Drying and Heating Modelling of Granular Flow: Application to the Mix-Asphalt Processes

    Directory of Open Access Journals (Sweden)

    L Le Guen

    2011-01-01

    Full Text Available Concrete asphalt is a hydrocarbon material that includes a mix of mineral components along with a bituminous binder. Prior to mixing, its production protocol requires drying and heating the aggregates. Generally performed in a rotary drum, these drying and heating steps within mix asphalt processes have never been studied from a physical perspective. We are thus proposing in the present paper to analyze the drying and heating mechanisms when granular materials and hot gases are involved in a co-current flow. This process step accounts for a large proportion of the overall energy consumed during hot-mix asphalt manufacturing. In the present context, the high energy cost associated with this step has encouraged developing new strategies specifically for the drying process. Applying new asphalt techniques so that an amount of moisture can be preserved in the asphalt concrete appears fundamental to such new strategies. This low-energy asphalt, also referred to as the "warm technique", depends heavily on a relevant prediction of the actual moisture content inside asphalt concrete during the mixing step. The purpose of this paper is to present a physical model dedicated to the evolution in temperature and moisture of granular solids throughout the drying and heating steps carried out inside a rotary drum. An initial experimental campaign to visualize inside a drum at the pilot scale (i.e. 1/3 scale has been carried out in order to describe the granular flow and establish the necessary physical assumptions for the drying and heating model. Energy and mass balance equations are solved by implementing an adequate heat and mass transfer coupling, yielding a 1D model from several parameters that in turn drives the physical modeling steps. Moreover, model results will be analyzed and compared to several measurements performed in an actual asphalt mix plant at the industrial scale (i.e. full scale.

  7. Deriving bedform phase diagrams

    Science.gov (United States)

    Tom Hickson

    Students prepare for this activity by working with a unidirectional flume with a sand bed. We adjust water depth, flow velocity, and channel slope to achieve a range of bed states, in an effort for them to understand the controls on bedforms. This portion of the activity could be done in lecture or via another exercise that makes use of digital video of actual experiments. The activity itself is a jigsaw: students form groups of three, each group responsible for plotting depth vs. velocity plots of bedform state for a single sand grain size range (0.10-0.14 mm, 0.5-0.64 mm, and 1.3-1.8 mm). These data are provided to them as Excel files and the data were directly 'stolen' from the original depth vs. velocity plots in Middleton and Southard (1984), Mechanics of Sediment Movement, SEPM Short Course Number 3. Datathief software (available free on the web) was used to steal the data. The data are arranged in columns: depth, velocity, and bedform type. Students must plot each of the different bedform types with a different symbol, then they have to define field boundaries. It is critical that they have never seen the original plots in their textbook. The goal is for them to derive them on their own, not to regurgitate what is in their textbook or elsewhere. After they complete their plots for each grain size range, the groups re-arrange themselves into groups of three with one representative from each of the grain size groups. They then must try to evaluate the effects of changing grain size on bedform state. Finally, after completing the exercise, the bedform analysis is linked to the cross stratification that is produced under conditions of high sediment fallout rates and the given bed state. The activity gives students practice working with realistic datasets, exposure to the role of physical modeling in sedimentary geology, and a chance to plot and interpret real data. Furthermore, it really solidifies the link between cross stratification and its dynamic interpretation from the rock record.

  8. Improving Web Database Access Using Decision Diagrams

    CERN Document Server

    Popel, D V; Popel, Denis V.; Al-Hakeem, Nawar

    2002-01-01

    In some areas of management and commerce, especially in Electronic commerce (E-commerce), that are accelerated by advances in Web technologies, it is essential to support the decision making process using formal methods. Among the problems of E-commerce applications: reducing the time of data access so that huge databases can be searched quickly; decreasing the cost of database design ... etc. We present the application of Decision Diagrams design using Information Theory approach to improve database access speeds. We show that such utilization provides systematic and visual ways of applying Decision Making methods to simplify complex Web engineering problems.

  9. Between Analogue and Digital Diagrams

    Directory of Open Access Journals (Sweden)

    Zoltan Bun

    2012-10-01

    Full Text Available This essay is about the interstitial. About how the diagram, as a method of design, has lead fromthe analogue deconstruction of the eighties to the digital processes of the turn of the millennium.Specifically, the main topic of the text is the interpretation and the critique of folding (as a diagramin the beginning of the nineties. It is necessary then to unfold its relationship with immediatelypreceding and following architectural trends, that is to say we have to look both backwards andforwards by about a decade. The question is the context of folding, the exchange of the analogueworld for the digital. To understand the process it is easier to investigate from the fields of artand culture, rather than from the intentionally perplicated1 thoughts of Gilles Deleuze. Both fieldsare relevant here because they can similarly be used as the yardstick against which the era itselfit measured. The cultural scene of the eighties and nineties, including performing arts, movies,literature and philosophy, is a wide milieu of architecture. Architecture responds parallel to itsera; it reacts to it, and changes with it and within it. Architecture is a medium, it has always beena medium, yet the relations are transformed. That’s not to say that technical progress, for exampleusing CAD-software and CNC-s, has led to the digital thinking of certain movements ofarchitecture, (it is at most an indirect tool. But the ‘up-to-dateness’ of the discipline, however,a kind of non-servile reading of an ‘applied culture’ or ‘used philosophy’2 could be the key.(We might recall here, parenthetically, the fortunes of the artistic in contemporary mass society.The proliferation of museums, the magnification of the figure of the artist, the existence of amassive consumption of printed and televised artistic images, the widespread appetite for informationabout the arts, all reflect, of course, an increasingly leisured society, but also relateprecisely to the fact that, faced with the tedium of everyday, real, lived experience, of the scientificillusion, of work and production, the world of art appears as a kind of last preserve of reality,where human beings can still find sustenance. Art is understood as being a space in whichthe fatigue of the contemporary subject can be salved away.3

  10. Numerical Tools for Multicomponent, Multiphase, Reactive Processes: Flow of CO{sub 2} in Porous Medium

    Energy Technology Data Exchange (ETDEWEB)

    Khattri, Sanjay Kumar

    2006-07-01

    The thesis is concerned with numerically simulating multicomponent, multiphase, reactive transport in heterogeneous porous medium. Such processes are ubiquitous, for example, deposition of green house gases, flow of hydrocarbons and groundwater remediation. Understanding such processes is important from social and economic point of view. For the success of geological sequestration, an accurate estimation of migration patterns of green-house gases is essential. Due to an ever increasing computer power, computational mathematics has become an important tool for predicting dynamics of porous media fluids. Numerical and mathematical modelling of processes in a domain requires grid generation in the domain, discretization of the continuum equations on the generated grid, solution of the formed linear or nonlinear system of discrete equations and finally visualization of the results. The thesis is composed of three chapters and eight papers. Chapter 2 presents two techniques for generating structured quadrilateral and hexahedral meshes. These techniques are called algebraic and elliptic methods. Algebraic techniques are by far the most simple and computationally efficient method for grid generation. Transfinite interpolation operators are a kind of algebraic grid generation technique. In this chapter, many transfinite interpolation operators for grid generation are derived from 1D projection operators. In this chapter, some important properties of hexahedral elements are also mentioned. These properties are useful in discretization of partial differential equations on hexahedral mesh, improving quality of the hexahedral mesh, mesh generation and visualization. Chapter 3 is about CO{sub 2} flow in porous media. In this chapter, we present the mathematical models and their discretization for capturing major physical processes associated with CO{sub 2} deposition in geological formations. Some important simulations of practical applications in 2D and 3D are presented. Chapter 4 presents Control Volume discretization on adaptive meshes. In this chapter, criteria for adaptive refinement and an adaptive algorithm is presented. The following papers are included in Part II Paper A: A New Smoothing Algorithm for Quadrilateral and Hexahedral Meshes presents an alternative to the Laplacian smoothing. The new smoothing is called the parallelogram smoothing. Parallelogram smoothing tries to fit a domain with the best possible parallelograms or parallelepipeds. Since many numerical methods in porous media flow such as the well known MPFA produces a symmetric system on parallelogram meshes. So, the parallelogram smoothing can be useful for porous media flow simulations. Error of streamline methods on parallelogram and parallelopiped mesh is minimum. Paper B: Hexahedral Mesh by Area Functional. We review the Area functional for generating hexahedral meshes. An algorithm for optimization of the area functional is presented. Since a global optimization can be computationally expensive, it is shown that such an optimization can be applied locally. Paper C: An Effective Quadrilateral Mesh Adaptation Paper is about generating adaptive quadrilateral meshes. We present an extension of the Area functional for generating adaptive meshes. Several numerical examples are reported for showing effectiveness of the functional. Generally for quadrilateral mesh adaptation, we solve a coupled system of non-linear partial differential equations such as the well known non-linear elliptic system. Presented new idea is simple and computationally efficient. The other big plus of the method is that even after generating the solution adapted grid, the cells remain convex. Paper D: Deposition of Green House Gases by Compositional Simulator: Long Term Reactive Transport of CO{sub 2} in the Sand of Utsira In this work, we present the mathematical models and their discretization for capturing major physical processes associated with CO{sub 2} sequestration/deposition in a porous medium. We verify our simulator by comparing our results against available results. We analyz

  11. The efficiency of turn-over processes in degraded peat as investigated under continuous flow conditions

    Science.gov (United States)

    Kleimeier, Christian; Karsten, Ulf; Janssen, Manon; Lennartz, Bernd

    2013-04-01

    Nitrate removal from run-off from agricultural land is in general required to reach a "good chemical status" of surface and groundwater bodies according to the European Water Framework Directive. Removing nitrates via heterotrophic denitrification is highly effective but requires stable anoxic environmental conditions as well as available organic carbon as an electron donator. Constructed wetlands, established on peat soils, through which the nitrate-loaded water is routed, may provide denitrification favorable conditions. A long-term flow experiment (mesocosm) was conducted employing a laboratory container set-up filled with decomposed peat aiming at quantifying the nitrate removal efficiency at various nitrate influx rates. The redox potential was measured at different depths to determine the spatial distribution of denitrificating zones. This new methodological approach allows the observation of biological nitrate turn over without interrupting the adjusted flow rate. We investigated the hydraulic properties and derived transport parameters for the mesocosm by analyzing experimental data from tracer tests. The obtained bromide breakthrough curves (BTC) were subjected to model analysis using the CXTFIT routine of the STANMOD software package. It could be demonstrated that the degraded peat has a dual porosity structure with roughly 40% of the pore water not participating in convective flow and transport processes. Further, the first flushing of mineralized nitrate upon rewetting and onset of flux may compromise any positive clean-up and nitrate removal effects occurring during long-term operation of peat wetlands. The development of the spatial sequence of bacterial cultures is characterized by the redox potential. It is dominated by the available substrates that serve as electron acceptors in bacterial respiration and occurs in a thermodynamically determined top-down order. The zonal development of the nitrate-consuming bacteria was observed and used to describe the removal efficiency of the mesocosm.

  12. Phase diagrams of two-lane driven diffusive systems

    International Nuclear Information System (INIS)

    We consider a large class of two-lane driven diffusive systems in contact with reservoirs at their boundaries and develop a stability analysis of mean-field profiles as a method to derive the phase diagrams of such systems. We illustrate the method by deriving phase diagrams for the asymmetric exclusion process coupled to various second lanes: a diffusive lane, an asymmetric exclusion process with advection in the same direction as the first lane, and an asymmetric exclusion process with advection in the opposite direction. The competing currents on the two lanes naturally lead to a very rich phenomenology and we find a variety of phase diagrams. It is shown that the stability analysis is equivalent to an 'extremal current principle' for the total current in the two lanes. We also point to classes of models where the analysis fails due to the lack of a dynamically stable current–density relation

  13. Basics of introduction to Feynman diagrams and electroweak interactions physics

    International Nuclear Information System (INIS)

    The Feynman diagrams are the main computational method for the evaluation of the matrix elements of different processes. Although it is a perturbative method, its significance is not restricted to perturbation theory only. In this book, the elements of quantum field theory, the Feynman diagram method, the theory of electroweak interactions and other topics are discussed. A number of classical weak and electroweak processes are considered in details. This involves, first of all, the construction of the matrix elements of the process using both the Feynman diagram method (when perturbation theory can be applied) and the invariance principles (when perturbation theory fails). Then the cross sections and the decay probabilities are computed. The text is providing widely used computational techniques and some experimental data. (A.B.). 32 refs., 7 appendix

  14. Trigeneration System: Visualization through Ternary Diagrams

    Directory of Open Access Journals (Sweden)

    R.R. Tan

    2014-01-01

    Full Text Available The simultaneous production of power, heat and refrigeration in trigeneration plants is potentially more efficient than producing these same utilities in separate facilities, mainly due to the increased opportunities for process integration. Hence, trigeneration is also inherently more cost-effective and thermodynamically efficient, resulting in lower CO2 footprint. Various methods have been developed for the synthesis of such plants. In this study, we propose a graphical approach where power, heat and refrigeration or cooling form the vertices of a ternary diagram. A thermal process unit may thus be represented as a point within the ternary diagram, with its coordinates denoting the ratios of its heat, power and cooling outputs. Thus, units producing two streams lie along the edges of the triangular field while those producing three streams fall inside it. Subsequently sizing of such process units that make up a trigeneration plant can be accomplished using lever-arm mixing rules within this triangular coordinate system. The use of the graphical methodology is illustrated with two case studies.

  15. Large deviations in stochastic heat-conduction processes provide a gradient-flow structure for heat conduction

    Energy Technology Data Exchange (ETDEWEB)

    Peletier, Mark A., E-mail: m.a.peletier@tue.nl [Department of Mathematics and Computer Science and Institute for Complex Molecular Systems, Technische Universiteit Eindhoven, Postbus 513, 5600 MB Eindhoven (Netherlands); Redig, Frank, E-mail: f.h.j.redig@tudelft.nl [Delft Institute of Applied Mathematics, Technische Universiteit Delft, Mekelweg 4, 2628 CD Delft (Netherlands); Vafayi, Kiamars, E-mail: k.vafayi@tue.nl [Department of Mathematics and Computer Science, Technische Universiteit Eindhoven, Postbus 513, 5600 MB Eindhoven (Netherlands)

    2014-09-15

    We consider three one-dimensional continuous-time Markov processes on a lattice, each of which models the conduction of heat: the family of Brownian Energy Processes with parameter m (BEP(m)), a Generalized Brownian Energy Process, and the Kipnis-Marchioro-Presutti (KMP) process. The hydrodynamic limit of each of these three processes is a parabolic equation, the linear heat equation in the case of the BEP(m) and the KMP, and a nonlinear heat equation for the Generalized Brownian Energy Process with parameter a (GBEP(a)). We prove the hydrodynamic limit rigorously for the BEP(m), and give a formal derivation for the GBEP(a). We then formally derive the pathwise large-deviation rate functional for the empirical measure of the three processes. These rate functionals imply gradient-flow structures for the limiting linear and nonlinear heat equations. We contrast these gradient-flow structures with those for processes describing the diffusion of mass, most importantly the class of Wasserstein gradient-flow systems. The linear and nonlinear heat-equation gradient-flow structures are each driven by entropy terms of the form ?log??; they involve dissipation or mobility terms of order ?{sup 2} for the linear heat equation, and a nonlinear function of ? for the nonlinear heat equation.

  16. Large deviations in stochastic heat-conduction processes provide a gradient-flow structure for heat conduction

    Science.gov (United States)

    Peletier, Mark A.; Redig, Frank; Vafayi, Kiamars

    2014-09-01

    We consider three one-dimensional continuous-time Markov processes on a lattice, each of which models the conduction of heat: the family of Brownian Energy Processes with parameter m (BEP(m)), a Generalized Brownian Energy Process, and the Kipnis-Marchioro-Presutti (KMP) process. The hydrodynamic limit of each of these three processes is a parabolic equation, the linear heat equation in the case of the BEP(m) and the KMP, and a nonlinear heat equation for the Generalized Brownian Energy Process with parameter a (GBEP(a)). We prove the hydrodynamic limit rigorously for the BEP(m), and give a formal derivation for the GBEP(a). We then formally derive the pathwise large-deviation rate functional for the empirical measure of the three processes. These rate functionals imply gradient-flow structures for the limiting linear and nonlinear heat equations. We contrast these gradient-flow structures with those for processes describing the diffusion of mass, most importantly the class of Wasserstein gradient-flow systems. The linear and nonlinear heat-equation gradient-flow structures are each driven by entropy terms of the form -log ?; they involve dissipation or mobility terms of order ?2 for the linear heat equation, and a nonlinear function of ? for the nonlinear heat equation.

  17. Power Network Voronoi Diagram and Dynamic Construction

    Directory of Open Access Journals (Sweden)

    Yili Tan

    2012-04-01

    Full Text Available Objective Voronoi diagrams are important in many fields in a series of sciences. Network Voronoi diagrams are useful to investigate dominance regions in a grid street system or a radial-circular street system. However, all generators may have different effect. To deal with a network Voronoi diagram with varied functions of generators, it must be worth formulating a power network Voronoi diagram. Method Adding weight value on generators, which is used to indicate factors related to are difficult to construct when the position relation of generators.  Results A new concept of power network Voronoi diagram are proposed. In accordance with discrete construction method, achieved the construction of power network Voronoi diagram. Conclution The application example shows that the algorithm is both simple and useful, and it is of high potential value in practice.  Power network Voronoi diagram both perfected the theory about Voronoi diagrams, and extended the range of applications of Voronoi diagrams.

  18. Development of the flow behavior model for 3D scaffold fabrication in the polymer deposition process by a heating method

    International Nuclear Information System (INIS)

    The flow behavior model for 3D scaffold fabrication in the polymer deposition process by the heating method was developed for enhanced efficiency of the deposition process. The analysis of the polymer flow property is very important in the fabrication process of precise micro-structures such as scaffolds. In this study, a deposition model considering fluid mechanics and heat transfer phenomena was built up and introduced for the estimation of the fluid behavior of molten polymer. The effectiveness of the simulation model was verified through comparison with the experimental result in the case of PCL biomaterial. In addition, the effects of various parameters, such as pressure, temperature and nozzle size, were predicted through simulation before experimental approaches. Through the fabrication of 3D scaffold, it is concluded that this model is useful in predicting the flow behavior characteristics in the micro-structure fabrication process, which is based on the heating method

  19. Multiplexed fibre optic sensors for monitoring resin infusion, flow, and cure in composite material processing

    Science.gov (United States)

    Chehura, Edmon; Jarzebinska, Renata; Da Costa, Elisabete F. R.; Skordos, Alexandros A.; James, Stephen W.; Partridge, Ivana K.; Tatam, Ralph P.

    2013-04-01

    The infusion, flow and cure of RTM6 resin in a carbon fibre reinforced composite preform have been monitored using a variety of multiplexed fibre optic sensors. Optical fibre Fresnel sensors and tilted fibre Bragg grating (TFBG) sensors were configured to monitor resin infusion/flow in-plane of the component. The results obtained from the different sensors were in good agreement with visual observations. The degree of cure was monitored by Fresnel sensors via a measurement of the refractive index of the resin which was converted to degree of cure using a calibration determined from Differential Scanning Calorimetry. Fibre Bragg grating sensors fabricated in highly linearly birefringent fibre were used to monitor the development of transverse strain during the cure process, revealing through-thickness material shrinkage of about 712 ?? and residual strain of 223 ??. An alternative approach to infusion monitoring, based on an array of multiplexed tapered optical fibre sensors interrogated using optical frequency domain reflectometry, was also investigated in a separate carbon fibre preform that was infused with RTM6 resin.

  20. Energy efficiency enhancement of natural rubber smoking process by flow improvement using a CFD technique

    International Nuclear Information System (INIS)

    A non-uniform flow and large temperature variation in a natural rubber smoking-room cause an inefficient use of energy. Flow uniformity and temperature variation can be improved by using a computational fluid dynamics (CFD) simulation. The effects of the size, position and number of gas supply ducts and ventilating lids which were at the inlets and the outlets of the smoking-room were investigated. The optimal rubber smoking-room of size 2.6 m x 6.2 m x 3.6 m contains 154 50 mm-diameter hot gas supply ducts, and four 0.25 x 0.25 m and four 0.25 x 0.20 m ventilating lids. The velocity distribution of this model in the rubber-hanging area was rather uniform. The average monitoring temperature of 54 positions was 62.1 deg. C. This model could reduce the temperature variation by a factor of three from the original room model, i.e., from 15 to 5.5 deg. C. In a further study, the heat input of an appropriate room model was finely adjusted to obtain a suitable temperature (60 deg. C) for the smoking process. It was found that an appropriate heat supply at this temperature is 11 kW. At this rate, the temperature variation is 5.3 deg. C. This improved model should help the rubber smoking cooperatives to achieve at least a 31.25% saving in energy

  1. Groundwater flow, multicomponent transport and biogeochemistry: development and application of a coupled process model

    Energy Technology Data Exchange (ETDEWEB)

    Chilakapati, Ashokkumar (BATTELLE (PACIFIC NW LAB)); Yabusaki, Steven B.(BATTELLE (PACIFIC NW LAB)); Szecsody, James E.(BATTELLE (PACIFIC NW LAB)); Macevoy, Warren D.(ASSOC WESTERN UNIVERSITY)

    1999-12-01

    A research tool for modeling the reactive flow and transport of groundwater contaminants in multiple dimensions is presented. Arbitrarily complex coupled kinetic-equilibrium heterogeneous reaction networks, automatic code generation, transfer-function based solutions, parameter estimation, high-resolution methods for advection, and robust solvers for the mixed kinetic-equilibrium chemistry are some of the features of reactive flow and transport (RAFT) that make it a versatile research tool in the modeling of a wide variety of laboratory and field experiments. The treatment of reactions is quite general so that RAFT can be used to model biological, adsorption/desorption, complexation, and mineral dissolution/precipitation reactions among others. The integrated framework involving automated code generation and parameter estimation allows for the development, characterization, and evaluation of mechanistic process models. The model is described and used to solve a problem in competitive adsorption that illustrates some of these features. The model is also used to study the development of an in situ Fe(II)-zone by encouraging the growth of an iron-reducing bacterium with lactate as the electron donor. Such redox barriers are effective in sequestering groundwater contaminants such as chromate and TCE.

  2. Groundwater flow, multicomponent transport and biogeochemistry: development and application of a coupled process model

    Science.gov (United States)

    Chilakapati, Ashok; Yabusaki, Steve; Szecsody, James; MacEvoy, Warren

    2000-05-01

    A research tool for modeling the reactive flow and transport of groundwater contaminants in multiple dimensions is presented. Arbitrarily complex coupled kinetic-equilibrium heterogeneous reaction networks, automatic code generation, transfer-function based solutions, parameter estimation, high-resolution methods for advection, and robust solvers for the mixed kinetic-equilibrium chemistry are some of the features of reactive flow and transport (RAFT) that make it a versatile research tool in the modeling of a wide variety of laboratory and field experiments. The treatment of reactions is quite general so that RAFT can be used to model biological, adsorption/desorption, complexation, and mineral dissolution/precipitation reactions among others. The integrated framework involving automated code generation and parameter estimation allows for the development, characterization, and evaluation of mechanistic process models. The model is described and used to solve a problem in competitive adsorption that illustrates some of these features. The model is also used to study the development of an in situ Fe(II)-zone by encouraging the growth of an iron-reducing bacterium with lactate as the electron donor. Such redox barriers are effective in sequestering groundwater contaminants such as chromate and TCE.

  3. Groundwater flow, multicomponent transport and biogeochemistry: development and application of a coupled process model

    International Nuclear Information System (INIS)

    A research tool for modeling the reactive flow and transport of groundwater contaminants in multiple dimensions is presented. Arbitrarily complex coupled kinetic-equilibrium heterogeneous reaction networks, automatic code generation, transfer-function based solutions, parameter estimation, high-resolution methods for advection, and robust solvers for the mixed kinetic-equilibrium chemistry are some of the features of reactive flow and transport (RAFT) that make it a versatile research tool in the modeling of a wide variety of laboratory and field experiments. The treatment of reactions is quite general so that RAFT can be used to model biological, adsorption/desorption, complexation, and mineral dissolution/precipitation reactions among others. The integrated framework involving automated code generation and parameter estimation allows for the development, characterization, and evaluation of mechanistic process models. The model is described and used to solve a problem in competitive adsorption that illustrates some of these features. The model is also used to study the development of an in situ Fe(II)-zone by encouraging the growth of an iron-reducing bacterium with lactate as the electron donor. Such redox barriers are effective in sequestering groundwater contaminants such as chromate and TCE

  4. Assessment of ploidy stability of the somatic embryogenesis process in Quercus suber L. using flow cytometry.

    Science.gov (United States)

    Loureiro, J; Pinto, G; Lopes, T; Dolezel, J; Santos, C

    2005-08-01

    Flow cytometry analyses were used to verify the ploidy stability of Quercus suber L. somatic embryogenesis process. Leaf explants of two adult cork oak trees (QsG0 and QsG5) of the North of Portugal were inoculated on MS medium with 2,4-D and zeatin. After 3 months, calluses with embryogenic structures were isolated and transferred to fresh MS medium without growth regulators and somatic embryo evolution was followed. Morphologically normal somatic embryos (with two cotyledons) and abnormal somatic embryos (with one or three cotyledons) were used in this assay. Flow cytometry combined with propidium iodide staining was employed to estimate DNA ploidy levels and nuclear DNA content of somatic embryos and leaves from mother plants. No significant differences (P< or =0.05) were detected among embryos, and between the embryos and the mother plants. Also, after conversion of these embryos, no significant morphological differences were observed among the somatic embryo-derived plants. These results and further studies using converted plantlet leaves and embryogenic callus tissue indicate that embryo cultures and converted plantlets were stable with regard to ploidy level. As no major somaclonal variation was detected our primary goal of "true-to-type" propagation of cork oak using somatic embryogenesis was assured at this level. The estimation of the 2C nuclear DNA content for this species is similar to the previously obtained value. PMID:15744492

  5. Engineering Solution in Monitoring Nanoparticle-Fluid Flow During Nanocomposites Processing

    International Nuclear Information System (INIS)

    New generation composites using nanoparticle-filled matrices have been significantly broadened to encompass a large variety of one-, two-, and three-dimensional systems made of distinctly dissimilar components mixed at the nanometer scale. Nevertheless, during the fabrication process of these novel composites, many problems potentially could arise. One such problem is the clogging of the channels of the microfiber matrix used due to strong interactions between the nanoparticle additives and the matrix walls. In this paper, a two-dimensional simulation model based on Lagrangian multiphase approach for nanoparticle-filled fluid, which flows around an aligned microfiber matrix, is introduced to investigate and predict the nanoparticles trajectories and their interactions with fluid flow and microfiber walls. An energy 'imbalance' technique has been applied between the fluid and the microfiber walls to prevent any potential sticking of the nanoparticle additives on the microfiber walls. The trajectory of the nanoparticle has been predicted by integrating the force balance on it in a Lagrangian reference frame. The governing integral equations for the conservation of mass, momentum and energy have been solved in a segregated numerical fashion by a Control-Volume-Based Finite-Element Method

  6. Measurement technique of slug flow characteristics using image data processing. 2. Measurement technique of velocity field in wake region and liquid film velocity in slug flows

    International Nuclear Information System (INIS)

    Geysering may be induced during start-up in natural circulation boiling water reactors. It is necessary for simulation of this flow instability to model the coalescence mechanism and condensation process of slug bubbles. In this work, image data processing technique using a digital video camera has been developed to measure slug flow characteristics. In this technique, ultraviolet lighting with high frequency power source, laser sheet and stroboscope whose lighting frequency can be regulated are used as lighting and small nylon particles mixed into water are adopted for tracer. The developed measurement technique are applied for slug bubbles rising in stagnant water, and coalescence process of slug bubbles, liquid film velocity surrounding a slug bubble and velocity field in the wake region are measured. From these results, the capability of the developed measurement technique and the measurement accuracy are discussed. (author)

  7. Visualization of Liquid Metal Two-phase Flows in a Physical Model of the Continuous Casting Process of Steel

    Science.gov (United States)

    Timmel, Klaus; Shevchenko, Natalia; Röder, Michael; Anderhuber, Marc; Gardin, Pascal; Eckert, Sven; Gerbeth, Gunter

    2014-11-01

    We present an experimental study concerned with investigations of the two-phase flow in a mock-up of the continuous casting process of steel. A specific experimental facility was designed and constructed at HZDR for visualizing liquid metal two-phase flows in the mold and the submerged entry nozzle (SEN) by means of X-ray radioscopy. This setup operates with the low melting, eutectic alloy GaInSn as model liquid. The argon gas is injected through the tip of the stopper rod into the liquid metal flow. The system operates continuously under isothermal conditions. First results will be presented here revealing complex flow structures in the SEN widely differing from a homogeneously dispersed bubbly flow. The patterns are mainly dominated by large bubbles and large-area detachments of the liquid metal flow from the inner nozzle wall. Various flow regimes can be distinguished depending on the ratio between the liquid and the gas flow rate. Smaller gas bubbles are produced by strong shear flows near the nozzle ports. The small bubbles are entrained by the submerged jet and mainly entrapped by the lower circulation roll in the mold. Larger bubbles develop by coalescence and ascend toward the free surface.

  8. Neuraminidase Ribbon Diagram

    Science.gov (United States)

    2004-01-01

    Ribbons is a program developed at UAB used worldwide to graphically depict complicated protein structures in a simplified format. The program uses sophisticated computer systems to understand the implications of protein structures. The Influenza virus remains a major causative agent for a large number of deaths among the elderly and young children and huge economic losses due to illness. Finding a cure will have a general impact both on the basic research of viral pathologists of fast evolving infectious agents and clinical treatment of influenza virus infection. The reproduction process of all strains of influenza are dependent on the same enzyme neuraminidase. Shown here is a segmented representation of the neuraminidase inhibitor compound sitting inside a cave-like contour of the neuraminidase enzyme surface. This cave-like formation present in every neuraminidase enzyme is the active site crucial to the flu's ability to infect. The space-grown crystals of neuraminidase have provided significant new details about the three-dimensional characteristics of this active site thus allowing researchers to design drugs that fit tighter into the site. Principal Investigator: Dr. Larry DeLucas

  9. Materials And Carbon Flow In A Waste Refinery Process Using Enzymes

    DEFF Research Database (Denmark)

    Tonini, Davide; Woods, M.

    2011-01-01

    Recovery of resources from mixed Municipal Solid Waste (MSW) is a crucial aspect of waste management practices. In this paper the materials and carbon flows of an innovative waste refinery process using enzymes are presented. Through enzymatic treatment the process produces two main streams from the initial mixed MSW: a bioslurry (liquefied paper and organics) and a solid fraction (non-degradable materials). The discussion is based on the performance of the process in separating recyclables and recovery Cbiogenic as well as nutrients from the input MSW. The results of MFA and SFA illustrate that the waste refinery has great potential for resource recovery: about 100% of the Cbiogenic and up to 90% of N and P can potentially be recovered in the bioslurry and returned to land after anaerobic digestion. Recovery of ferrous and non-ferrous material is estimated double compared to recovering the same material from bottom ash after incineration (current scenario). Hard plastic can also be separated and recovered. Potentially, only residual 20% of the initial MSW is to be incinerated after refining and separation of metals and plastic.

  10. Effects of Micromachining Processes on Electro-Osmotic Flow Mobility of Glass Surfaces

    Directory of Open Access Journals (Sweden)

    Norihisa Miki

    2013-03-01

    Full Text Available Silica glass is frequently used as a device material for micro/nano fluidic devices due to its excellent properties, such as transparency and chemical resistance. Wet etching by hydrofluoric acid and dry etching by neutral loop discharge (NLD plasma etching are currently used to micromachine glass to form micro/nano fluidic channels. Electro-osmotic flow (EOF is one of the most effective methods to drive liquids into the channels. EOF mobility is affected by a property of the micromachined glass surfaces, which includes surface roughness that is determined by the manufacturing processes. In this paper, we investigate the effect of micromaching processes on the glass surface topography and the EOF mobility. We prepared glass surfaces by either wet etching or by NLD plasma etching, investigated the surface topography using atomic force microscopy, and attempted to correlate it with EOF generated in the micro-channels of the machined glass. Experiments revealed that the EOF mobility strongly depends on the surface roughness, and therefore upon the fabrication process used. A particularly strong dependency was observed when the surface roughness was on the order of the electric double layer thickness or below. We believe that the correlation described in this paper can be of great help in the design of micro/nano fluidic devices.

  11. Algebraic Generalization of Venn Diagram

    OpenAIRE

    Smarandache, Florentin

    2010-01-01

    It is easy to deal with a Venn Diagram for 1 ? n ? 3 sets. When n gets larger, the picture becomes more complicated, that's why we thought at the following codification. That's why we propose an easy and systematic algebraic way of dealing with the representation of intersections and unions of many sets.

  12. Class Diagram Restructuring with GROOVE

    OpenAIRE

    Wietse Smid; Arend Rensink

    2013-01-01

    This paper describes the GROOVE solution to the "Class Diagram Restructuring" case study of the Tool Transformation Contest 2013. We show that the visual rule formalism enables the required restructuring to be formulated in a very concise manner. Moreover, the GROOVE functionality for state space exploration allows checking confluence. Performance-wise, however, the solution does not scale well.

  13. Venn Diagram Warm-Up

    Science.gov (United States)

    M Johnson

    2013-10-02

    This response answers a posted question, "What is your favorite warm-up suited for all grade levels?". The response details a Venn Diagram warm-up that can be used with any grade level and modified to fit most math topics.

  14. Voronoi Diagrams and Spring Rain

    Science.gov (United States)

    Perham, Arnold E.; Perham, Faustine L.

    2011-01-01

    The goal of this geometry project is to use Voronoi diagrams, a powerful modeling tool across disciplines, and the integration of technology to analyze spring rainfall from rain gauge data over a region. In their investigation, students use familiar equipment from their mathematical toolbox: triangles and other polygons, circumcenters and…

  15. Numerical Modeling of the Flow of a Power Law Ceramic Slurry in the Tape Casting Process

    DEFF Research Database (Denmark)

    Jabbari, Masoud; Hattel, Jesper Henri

    2012-01-01

    Multilayer ceramics and their application have increased recently. One of the most common ways used to produce these products is tape casting. In this process the wet tape thickness is one of the most determining parameters affecting the final properties of the product and it is therefore of great interest to be able to control it. In the present work the flow of La0.85Sr0.15MnO3 (LSM) material in the doctor blade region is modelled numerically with ANSYS Fluent in combination with an Ostwald power law constitutive equation. Based on rheometer experiments the constants in the Ostwald power law are identified for the considered LSM material and applied in the numerical modelling for the tape thickness. This model is then used for different values of substrate velocity and material load in the reservoir and compared with experimental findings of the wet tape thickness and good agreement is found.

  16. In situ vitrification: Numerical studies of coupled heat transfer and viscous flow processes

    Energy Technology Data Exchange (ETDEWEB)

    Carey, G.F.; MacKinnon, R.J.; Murray, P.E.

    1990-09-01

    This report describes the formulation, results and conclusions of a series of numerical studies performed to support the Idaho National Engineering Laboratory (INEL) In Situ Vitrification (ISV) treatability study. These studies were designed to explore some of the questions related to the dominant physical phenomena associated with the coupled electric field, heat transfer, and fluid flow processes. The work examines the case of a 3-D axisymmetric problem with a central electrode. Such issues as the form of an electric heating model, choice of boundary conditions, latent heat effects, and conductive and convective transport are considered. Some important conclusions and recommendations are made in relation to the convective effects, determination of property parameters, and the issue of a valid electrical heating model. 4 refs., 100 figs., 1 tab.

  17. Fluctuations and pseudo long range dependence in network flows: A non-stationary Poisson process model

    International Nuclear Information System (INIS)

    In the study of complex networks (systems), the scaling phenomenon of flow fluctuations refers to a certain power-law between the mean flux (activity) (Fi) of the i-th node and its variance ?i as ?i ? (Fi)?. Such scaling laws are found to be prevalent both in natural and man-made network systems, but the understanding of their origins still remains limited. This paper proposes a non-stationary Poisson process model to give an analytical explanation of the non-universal scaling phenomenon: the exponent ? varies between 1/2 and 1 depending on the size of sampling time window and the relative strength of the external/internal driven forces of the systems. The crossover behaviour and the relation of fluctuation scaling with pseudo long range dependence are also accounted for by the model. Numerical experiments show that the proposed model can recover the multi-scaling phenomenon. (general)

  18. Growth and Improvement of ZnO Nanostructure Using Aged Solution by Flow Coating Process

    Directory of Open Access Journals (Sweden)

    Kasimayan Uma

    2013-07-01

    Full Text Available ZnO nanostructures were prepared on corning glass substrate by flow coating process with different annealing temperature from 100?C to 600?C. Fresh and two days aged solutions were used to investigate the growth behavior and to evaluate the nanostructure of ZnO. The effect of preparation conditions on the deposition of ZnO nanostructure was investigated by scanning electron microscopy (SEM, X-ray diffraction (XRD, Raman, and photoluminescence spectroscopy (PL. The results indicated that the solution aging condition and annealing temperature have a strong influence on the morphology and structural properties of the ZnO nanostructure. The solution aged after two days shows the different morphologies compared with the freshly prepared solution.

  19. Multiphase flow importance in future nuclear process heat applications: energy alcohol by biomass gasification with HTR

    International Nuclear Information System (INIS)

    For future nuclear process heat applications multiphase phenomena are very important in a three-fold sense: For the ability to produce high temperature heat, for the realization of a catastrophe-free nuclear energy technology and for the newly proposed carbondioxide-neutral energy system 'energy alcohol from biomass plus HTR'. The technology of the 'Coated Particle' with the multi-coating of ceramic coatings on microparticles on nuclear fuel for the HTR is the technological reason for the ability to produce high temperature heat from nuclear energy. It is produced by chemical vapour deposition in a fluidized bed, this is a two-phase-fluidized-bed/gaseous-to-solid-states-change by pyrolysis/multi-component/phenomenon. The new requirement of a catastrophe-free nuclear energy technology has led to the identification that the ingress of water droplets into the nuclear core of the HTR should be avoided by self-acting separation of droplets coming from the steam generator tube break before they can get into the core. The behaviour of the water/steam jet in the helium stream is a two-phase-flow/far-from-equilibrium-phase-change/two-component/phenomenon. The biggest challenge to the energy industry is the carbondioxide-climate-change-problem. The solution requires the reduction of the application of fossil primary energy carriers by the factor of about 5 for the world, and e.g. by the factors of about 13 for FRG and about 10 for Japan. As a contribution to the solution a new . As a contribution to the solution a new proposal has been made recently: the production of energy alcohol, e.g. methanol, on the basis 'biomass plus HTR'. The main part of the energy conversion process is the helium-heated fluidized bed steam gasification of biomass. This a two-phase-flow/solid-to-gaseous states-change/pyrolysis and chemical reaction/multi-component/phenomenon. (J.P.N.)

  20. Numerical study of heat transport and fluid flow during the silicon crystal growth process by the Czochralski method

    International Nuclear Information System (INIS)

    A global analysis of heat transfer and fluid flow in a real Czochralski single silicon crystal furnace is developed using the FLUENT package. Good agreement was obtained for comparisons of the power and crystal growth speed between the simulation and experimental data, and the effect of the length of the crystal on heat transfer and fluid flow was analyzed. The results showed that Tmax increases and its location moves downward as the crystal length increases. The flow pattern in the melt does not change until the crystal grows to 900 mm. As the crystal length increases, the flow pattern in the first gas area only changes when the crystal length is less than 700 mm, but the flow pattern in the second area changes throughout the growth process. (semiconductor materials)

  1. Numerical study of heat transport and fluid flow during the silicon crystal growth process by the Czochralski method

    Science.gov (United States)

    Chaohua, Jin

    2013-06-01

    A global analysis of heat transfer and fluid flow in a real Czochralski single silicon crystal furnace is developed using the FLUENT package. Good agreement was obtained for comparisons of the power and crystal growth speed between the simulation and experimental data, and the effect of the length of the crystal on heat transfer and fluid flow was analyzed. The results showed that Tmax increases and its location moves downward as the crystal length increases. The flow pattern in the melt does not change until the crystal grows to 900 mm. As the crystal length increases, the flow pattern in the first gas area only changes when the crystal length is less than 700 mm, but the flow pattern in the second area changes throughout the growth process.

  2. REPRESENTING MARKOV CHAINS WITH TRANSITION DIAGRAMS

    Directory of Open Access Journals (Sweden)

    Farida Kachapova

    2013-01-01

    Full Text Available Stochastic processes have many useful applications and are taught in several university programmes. Students often encounter difficulties in learning stochastic processes and Markov chains, in particular. In this article we describe a teaching strategy that uses transition diagrams to represent a Markov chain and to re-define properties of its states in simple terms of directed graphs. This strategy utilises the studentsâ?? intuition and makes the learning of complex concepts about Markov chains faster and easier. The method is illustrated by worked examples. The described strategy helps students to master properties of finite Markov chains, so they have a solid basis for the study of infinite Markov chains and other stochastic processes.

  3. Long term impacts of flow abstraction upon basin scale sedimentation processes in an Alpine valley system

    Science.gov (United States)

    Lane, Stuart; Regamey, Benoit

    2014-05-01

    Flow abstraction and diversion to large water storage systems is a common element of Alpine hydro-electric power schemes. However, such systems are commonly associated with exceptionally high sediment production rates, necessitating very particular approaches to sediment management. Commonly, whilst water is abstracted, sediment (both coarse and fine fractions) is left behind. In order to avoid infrastructure failure, the latter is commonly designed to allow sediment to pass in short duration high magnitude sedimentary floods. The importance of such schemes aside, there has been relatively little investigation of the geomorphic impacts of such sediment management systems. In this paper, we present results from two spatio-temporal scales of analysis in order to establish these impacts. The first applies image processing to archival aerial photography to document the long-term impacts of flow abstraction and sedimentary floods in the Val d'Héréns, Switzerland. Results show that flow abstraction significantly reduces the time when the river was competent to transport sediment, and hence the total sediment transport capacity. The result has been a temporary disconnection of sediment flux through the system, and reflected in significantly reduced rates of sediment delivery to Lac Léman downstream. However, the image analysis also shows that whilst sedimentation was initially restricted to close to the abstraction sites, this sediment has been progressively reworked through a succession of sedimentary floods, causing deposition sites to move progressively further downstream. These deposition sites are themselves constrained by geomorphic forcing, centred on reaches of lower river bed slope and with sufficient lateral accommodation space. The implication of these observations is that the sediment flux will eventually reconnect with the main valley stems further downstream. The second scale sought to quantify this response in more detail by laser scanning on a 400 m river reach. This smaller scale of study explains this process of temporary disconnection showing that there is an autocyclic dynamic feedback between deposition in previous purges, extant morphology and the effects of the next purges which controls the timescale of sediment flux, and hence the disconnection rate,

  4. Dynamic relaxation processes in compressible multiphase flows. Application to evaporation phenomena

    Directory of Open Access Journals (Sweden)

    Le Métayer O.

    2013-07-01

    Full Text Available Phase changes and heat exchanges are examples of physical processes appearing in many industrial applications involving multiphase compressible flows. Their knowledge is of fundamental importance to reproduce correctly the resulting effects in simulation tools. A fine description of the flow topology is thus required to obtain the interfacial area between phases. This one is responsible for the dynamics and the kinetics of heat and mass transfer when evaporation or condensation occurs. Unfortunately this exchange area cannot be obtained easily and accurately especially when complex mixtures (drops, bubbles, pockets of very different sizes appear inside the transient medium. The natural way to solve this specific trouble consists in using a thin grid to capture interfaces at all spatial scales. But this possibility needs huge computing resources and can be hardly used when considering physical systems of large dimensions. A realistic method is to consider instantaneous exchanges between phases by the way of additional source terms in a full non-equilibrium multiphase flow model [2,15,17]. In this one each phase obeys its own equation of state and has its own set of equations and variables (pressure, temperature, velocity, energy, entropy,.... When enabling the relaxation source terms the multiphase mixture instantaneously tends towards a mechanical or thermodynamic equilibrium state at each point of the flow. This strategy allows to mark the boundaries of the real flow behavior and to magnify the dominant physical effects (heat exchanges, evaporation, drag,... inside the medium. A description of the various relaxation processes is given in the paper. Les changements de phase et les transferts de chaleur sont des exemples de phénomènes physiques présents dans de nombreuses applications industrielles faisant intervenir des écoulements compressibles multiphasiques. La connaissance des mécanismes associés est primordiale afin de reproduire correctement leurs effets à travers des outils de simulation. Dans ce cadre, une description fine de la topologie d’un écoulement est nécessaire afin de connaître précisément l’aire interfaciale entre toutes les phases. Celle-ci est en effet responsable de la dynamique et de la cinétique des transferts de masse et de chaleur lorsque de l’évaporation et de la condensation se produisent. Malheureusement cette aire interfaciale est difficilement accessible particulièrement lorsque des mélanges complexes se forment (gouttes, bulles, inclusions de différentes tailles au sein du milieu. La façon la plus naturelle de résoudre ce problème est d’utiliser un maillage suffisamment fin afin de capturer toutes les interfaces présentes à toutes les échelles. Cependant cette possibilité demanderait des ressources informatiques démesurées au vue de certains systèmes pouvant être de très grande taille. Une méthode plus réaliste est de considérer que les échanges entre les phases s’effectuent instantanément. Des termes sources de relaxation liés à ces échanges sont utilisés dans un modèle d’écoulement compressible à phases séparées en déséquilibre [2,15,17]. Dans celui-ci, chaque phase possède son propre jeu d’équations et ses propres variables (pression, vitesse, température, énergie, entropie, .... Quand les termes de relaxation sont activés, le mélange multiphasique tend instantanément en chaque point de l’écoulement vers un état d’équilibre prédéfini. Cette approche permet également de borner les conditions réelles d’écoulement et de souligner les effets physiques dominants (transfert de chaleur, évaporation, trainée, .... Une description des différents processus de relaxation est proposée dans ce papier.

  5. Automated calculation of Feynman diagrams

    International Nuclear Information System (INIS)

    Calculating Standard Model predictions in the context of perturbation theory is demanding. The challenge lies in the calculation of more and more complicated Feynman diagrams and in the increasing size of the calculation for scattering events with a large number of particles. New mathematical methods have to be developed and the increasing complexity has to be tamed by automatisation. A short introduction to the subject is given in chapter 2. Subsequent chapters deal with particular contributions to the solution of these problems. In chapter 3 we present a project that is going to be important for the analyses of the LHC data. The goal of the project is the calculation of oneloop corrections to processes with many particles in the final state. The numerical procedure is described and explained. It uses helicity spinors and a new tensor reduction method that avoids problems with inverse Gram determinants to a large extent. A computer program was developed that can perform the calculations automatically. The implementation is described and details about the optimization and verification are presented. Chapter 4 is concerned with analytical methods. An introduction to the xloops project is given, which can calculate various Feynman integrals analytically with arbitrary masses and momentum configurations. The major mathematical methods employed by xloops to solve the integrals are explained. Two ideas for new methods of calculation are presented. On the one hand it is then are presented. On the one hand it is the uniform treatment of one-loop N-point integrals, on the other hand it is the automated series expansion of integral solutions into higher orders of the dimensional regularization parameter ?. First results for the latter method are presented. The usefulness of the methods for automated series expansion from chapter 4 depend on the ability to numerically evaluate the expansion coefficients. The coefficients are in general multiple polylogarithms. In chapter 5 a method for the numerical evaluation of multiple polylogarithms is presented. This new method was implemented into the C++ library GiNaC together with other polylogarithms. (Orig.)

  6. The high moisture western coal processing system at the UTSI-DOE Coal Fired Flow Facility. Topical report

    Energy Technology Data Exchange (ETDEWEB)

    Sanders, M.E.

    1996-02-01

    The original eastern coal processing system at the Department of Energy`s Coal Fired Flow Facility (CFFF), located at the University of Tennessee Space Institute in Tullahoma, Tennessee, was modified to pulverize and dry Montana Rosebud, a western coal. Significant modifications to the CFFF coal processing system were required and the equipment selection criteria are reviewed. Coal processing system performance parameters are discussed. A summary of tests conducted and significant events are included.

  7. Continuous flow microwave-assisted processing and aseptic packaging of purple-fleshed sweetpotato purees.

    Science.gov (United States)

    Steed, L E; Truong, V-D; Simunovic, J; Sandeep, K P; Kumar, P; Cartwright, G D; Swartzel, K R

    2008-11-01

    Pumpable purees from purple-flesh sweetpotatoes (PFSP) were subjected to microwave heating using a 60 kW, 915 MHz continuous flow system, followed by aseptic packaging in flexible containers to obtain a shelf-stable product. Initial test runs were conducted using a 5 kW 915 MHz microwave system to measure dielectric in-line properties and examine the puree temperature profiles. The results demonstrated uniformity in heating of the puree at sterilization temperatures (>121 degrees C), and the dielectric constants and loss factors were within the range of published values for orange-fleshed sweetpotato purees. The pilot-scale test runs in a 60 kW microwave unit produced shelf-stable puree packages stable at room temperature. Polyphenolic content of the PFSP purees were evaluated and the results showed that while total phenolics increased (5.9%) and total monomeric anthocyanins slightly decreased (14.5%) with microwave application, antioxidant activity determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and oxygen radical absorbance capacity (ORAC) assays did not significantly change as a result of microwave processing. Color values showed that microwave-processed samples differed from fresh puree in saturation and hue angle, but not in overall color change. PFSP purees increased in gel strength when microwave processed, packaged, and stored, but the gel could be easily disrupted into flowable purees. Overall, high-quality retention can be obtained by microwave processing and aseptic packaging of PFSP purees so that they can be used as functional food ingredients. PMID:19021801

  8. Measurement of void fraction in flow boiling of ZnO–water nanofluids using image processing technique

    International Nuclear Information System (INIS)

    Highlights: • Void fraction during flow boiling of nanofluids measured using optical techniques. • Bubble behavior of nanofluids was investigated and compared with water. • Nanofluids showed lower void fraction as compared to water. • Void fraction decreases with increasing nanoparticle concentration and flow rate. • Void fraction increases with heat flux and axial location of heated length. - Abstract: In recent years, nanofluids have been an active area of research in many engineering applications, especially for nuclear reactor safety systems due to their enhanced thermal properties as a coolant. In this study, experiments were performed in subcooled flow boiling of water and ZnO–water nanofluids with different nanoparticle concentrations (0.001–0.01 vol.%) in horizontal annulus at heat fluxes varying from 100 to 550 kW/m2 and flow rates from 0.1 to 0.175 lps at 1 bar inlet pressure and constant subcooling of 20 °C to determine the void fraction by image processing technique. Parametric effects of nanoparticle volume fraction, heat flux, flow rate and axial location of heater rod on void fraction were studied. Bubble images during flow boiling were captured with high speed visualization and analyzed by National Instruments IMAQ Vision Builder 6.1 image processing software. Results show that void fraction decreases up to 86% with the use of nanofluid in place of water and it also decreases with increasing nanoparticle concentration and flow rate, whereas increase in heat flux and axial location of heater rod have opposite effect

  9. Measurement of void fraction in flow boiling of ZnO–water nanofluids using image processing technique

    Energy Technology Data Exchange (ETDEWEB)

    Rana, K.B., E-mail: kunj.216@gmail.com [Department of Mechanical Engineering, Malaviya National Institute of Technology, Jaipur (India); Agrawal, G.D.; Mathur, J. [Department of Mechanical Engineering, Malaviya National Institute of Technology, Jaipur (India); Puli, U. [Faculty of Mechanical Engineering, Department of Technical Education, Government of Andhra Pradesh, Hyderabad (India)

    2014-04-01

    Highlights: • Void fraction during flow boiling of nanofluids measured using optical techniques. • Bubble behavior of nanofluids was investigated and compared with water. • Nanofluids showed lower void fraction as compared to water. • Void fraction decreases with increasing nanoparticle concentration and flow rate. • Void fraction increases with heat flux and axial location of heated length. - Abstract: In recent years, nanofluids have been an active area of research in many engineering applications, especially for nuclear reactor safety systems due to their enhanced thermal properties as a coolant. In this study, experiments were performed in subcooled flow boiling of water and ZnO–water nanofluids with different nanoparticle concentrations (0.001–0.01 vol.%) in horizontal annulus at heat fluxes varying from 100 to 550 kW/m{sup 2} and flow rates from 0.1 to 0.175 lps at 1 bar inlet pressure and constant subcooling of 20 °C to determine the void fraction by image processing technique. Parametric effects of nanoparticle volume fraction, heat flux, flow rate and axial location of heater rod on void fraction were studied. Bubble images during flow boiling were captured with high speed visualization and analyzed by National Instruments IMAQ Vision Builder 6.1 image processing software. Results show that void fraction decreases up to 86% with the use of nanofluid in place of water and it also decreases with increasing nanoparticle concentration and flow rate, whereas increase in heat flux and axial location of heater rod have opposite effect.

  10. Fundamental change of granular flows dynamics, deposition and erosion processes at sufficiently high slope angles: insights from laboratory experiments

    Science.gov (United States)

    Farin, M.; Mangeney, A.; Roche, O.

    2013-12-01

    Geophysical granular flows commonly interact with their substrate in various ways depending on the mechanical properties of the underlying material. Granular substrates, resulting from deposition of earlier flows or various geological events, are often eroded by avalanches [see Hungr and Evans, 2004 for review]. The entrainment of underlying debris by the flow is suspected to affect flow dynamics because qualitative and quantitative field observations suggest that it can increase the flow velocity and deposit extent, depending on the geological setting and flow type [Sovilla et al., 2006; Iverson et al., 2011]. Direct measurement of material entrainment in nature, however, is very difficult. We conducted laboratory experiments on granular column collapse over an inclined channel with and without an erodible bed of granular material. The controlling parameters were the channel slope angle, the granular column volume and its aspect ratio (i.e. height over length), the inclination of the column with respect to the channel base, the channel width, and the thickness and compaction of the erodible bed. For slope angles below a critical value ?c, between 10° and 16°, the runout distance rf is proportional to the initial column height h0 and is unaffected by the presence of an erodible bed. On slopes greater than ?c, the flow dynamics change fundamentally since a last phase of slow propagation develops at the end of the flow front deceleration, and prolongates significantly the flow duration. This phase has similar characteristics that steady, uniform flows. The slow propagation phase lasts longer for increasing column volume, column inclination with respect to the slope, and channel width, and for decreasing column aspect ratio. It is however independent of the maximum front velocity and, on an erodible bed, of the maximum depth of excavation within the bed. Both on rigid and erodible beds, the increase of the slow propagation phase duration has a crucial effect on the granular flows dynamics and deposition. (i) On a rigid bed, as the slow propagation phase lasts longer, the normalized runout distance rf/h0 is greater for a given slope angle and the front of the flow deposit becomes more round. (ii) On an erodible bed, increasing the duration of the slow phase causes the bed excavation to lasts longer and the increase of the runout distance compared with the case on the rigid bed to be greater; this is even more significant as the bed is less compact. For flows on an erodible bed and if the slope angle is high enough, waves of grains appear in the flow head, at the interface between the flow (white) and the bed (black). These waves are related to the erosion/deposition processes at the base of the flow.

  11. Adapting of the Background-Oriented Schlieren (BOS) Technique in the Characterization of the Flow Regimes in Thermal Spraying Processes

    Science.gov (United States)

    Tillmann, W.; Abdulgader, M.; Rademacher, H. G.; Anjami, N.; Hagen, L.

    2014-01-01

    In thermal spraying technique, the changes in the in-flight particle velocities are considered to be only a function of the drag forces caused by the dominating flow regimes in the spray jet. Therefore, the correct understanding of the aerodynamic phenomena occurred at nozzle out let and at the substrate interface is an important task in the targeted improvement in the nozzle and air-cap design as well as in the spraying process in total. The presented work deals with the adapting of an innovative technique for the flow characterization called background-oriented Schlieren. The flow regimes in twin wire arc spraying (TWAS) and high velocity oxygen fuel (HVOF) were analyzed with this technique. The interfering of the atomization gas flow with the intersected wires causes in case of TWAS process a deformation of the jet shape. It leads also to areas with different aero dynamic forces. The configurations of the outlet air-caps in TWAS effect predominantly the outlet flow characteristics. The ratio between fuel and oxygen determine the dominating flow regimes in the HVOF spraying jet. Enhanced understanding of the aerodynamics at outlet and at the substrate interface could lead to a targeted improvement in thermal spraying processes.

  12. Critical point analysis of phase envelope diagram

    Energy Technology Data Exchange (ETDEWEB)

    Soetikno, Darmadi; Siagian, Ucok W. R. [Department of Petroleum Engineering, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132 (Indonesia); Kusdiantara, Rudy, E-mail: rkusdiantara@s.itb.ac.id; Puspita, Dila, E-mail: rkusdiantara@s.itb.ac.id; Sidarto, Kuntjoro A., E-mail: rkusdiantara@s.itb.ac.id; Soewono, Edy; Gunawan, Agus Y. [Department of Mathematics, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132 (Indonesia)

    2014-03-24

    Phase diagram or phase envelope is a relation between temperature and pressure that shows the condition of equilibria between the different phases of chemical compounds, mixture of compounds, and solutions. Phase diagram is an important issue in chemical thermodynamics and hydrocarbon reservoir. It is very useful for process simulation, hydrocarbon reactor design, and petroleum engineering studies. It is constructed from the bubble line, dew line, and critical point. Bubble line and dew line are composed of bubble points and dew points, respectively. Bubble point is the first point at which the gas is formed when a liquid is heated. Meanwhile, dew point is the first point where the liquid is formed when the gas is cooled. Critical point is the point where all of the properties of gases and liquids are equal, such as temperature, pressure, amount of substance, and others. Critical point is very useful in fuel processing and dissolution of certain chemicals. Here in this paper, we will show the critical point analytically. Then, it will be compared with numerical calculations of Peng-Robinson equation by using Newton-Raphson method. As case studies, several hydrocarbon mixtures are simulated using by Matlab.

  13. Critical point analysis of phase envelope diagram

    Science.gov (United States)

    Soetikno, Darmadi; Kusdiantara, Rudy; Puspita, Dila; Sidarto, Kuntjoro A.; Siagian, Ucok W. R.; Soewono, Edy; Gunawan, Agus Y.

    2014-03-01

    Phase diagram or phase envelope is a relation between temperature and pressure that shows the condition of equilibria between the different phases of chemical compounds, mixture of compounds, and solutions. Phase diagram is an important issue in chemical thermodynamics and hydrocarbon reservoir. It is very useful for process simulation, hydrocarbon reactor design, and petroleum engineering studies. It is constructed from the bubble line, dew line, and critical point. Bubble line and dew line are composed of bubble points and dew points, respectively. Bubble point is the first point at which the gas is formed when a liquid is heated. Meanwhile, dew point is the first point where the liquid is formed when the gas is cooled. Critical point is the point where all of the properties of gases and liquids are equal, such as temperature, pressure, amount of substance, and others. Critical point is very useful in fuel processing and dissolution of certain chemicals. Here in this paper, we will show the critical point analytically. Then, it will be compared with numerical calculations of Peng-Robinson equation by using Newton-Raphson method. As case studies, several hydrocarbon mixtures are simulated using by Matlab.

  14. Critical point analysis of phase envelope diagram

    International Nuclear Information System (INIS)

    Phase diagram or phase envelope is a relation between temperature and pressure that shows the condition of equilibria between the different phases of chemical compounds, mixture of compounds, and solutions. Phase diagram is an important issue in chemical thermodynamics and hydrocarbon reservoir. It is very useful for process simulation, hydrocarbon reactor design, and petroleum engineering studies. It is constructed from the bubble line, dew line, and critical point. Bubble line and dew line are composed of bubble points and dew points, respectively. Bubble point is the first point at which the gas is formed when a liquid is heated. Meanwhile, dew point is the first point where the liquid is formed when the gas is cooled. Critical point is the point where all of the properties of gases and liquids are equal, such as temperature, pressure, amount of substance, and others. Critical point is very useful in fuel processing and dissolution of certain chemicals. Here in this paper, we will show the critical point analytically. Then, it will be compared with numerical calculations of Peng-Robinson equation by using Newton-Raphson method. As case studies, several hydrocarbon mixtures are simulated using by Matlab

  15. Shakedown of sulfuric acid flow test loop for thermo-chemical hydrogen production technology by IS process (Contract research)

    International Nuclear Information System (INIS)

    JAEA has been conducting R and D on thermo-chemical water splitting hydrogen production technology by an iodine-sulfur cycle (IS process) aiming to establish the technology with high-temperature gas-cooled reactors (HTGRs). The IS process uses sulfuric acid as a process fluid, which is a very corrosive fluid. For development of the sulfuric-acid decomposer in the pilot plant, the sulfuric-acid flow test loop (SFTL) was constructed to obtain flow boiling characteristics, and to confirm applicability of components such as pipelines, pumps and instrumentations. The SFTL consists of a sulfuric-acid boiling heat transfer test loop and a high temperature component test loop, whose maximum flow rates are 2.5L/min and 20L/min, respectively. This report presents outline of the SFTL and shakedown test results. (author)

  16. Ambiguity Resolution for Sketched Diagrams by Syntax Analysis Based on Graph Grammars

    OpenAIRE

    Brieler, Florian; Minas, Mark

    2008-01-01

    Sketching, i.e., drawing diagrams by hand and directly on the screen, is gaining popularity, as it is a comfortable and natural way to create and edit diagrams. Hand drawing is inherently imprecise, and often sloppy. As a consequence, when processing hand drawn diagrams with a computer, ambiguities arise: it is not always clear what part of the drawing is meant to represent what component. Resolution of these ambiguities is the main issue of sketching. Ambiguity can only be solved by explorin...

  17. PROCESS DESCRIPTION AND PRODUCT COST TO MANUFACTURE SUGARCANE BAGASSE-BASED GRANULAR ACTIVATED CARBON

    Science.gov (United States)

    Process flow diagrams and manufacturing costs were developed to convert sugarcane bagasse to granular activated carbon. Unit operations in the conversion process consisted of milling, pelletization, pyrolysis/activation, washing with acid and water, and drying/screening/collecting of the final prod...

  18. Quark diagrams and the ?- nonleptonic decays

    International Nuclear Information System (INIS)

    The quark-diagram model for nonleptonic two-body baryon decays is discussed and applied to the decay of the ?- particle. Current algebra is not employed, but the relation between the quark diagrams and current algebra is explored

  19. Interaction of density flow and geochemical processes on islands in the Okavanga Delta, Botswana

    OpenAIRE

    Bauer-gottwein, Peter; Langer, T.; Prommer, H.; Wolski, P.; Kinzelbach, W.

    2012-01-01

    This paper analyses the interactions of density driven flow and geochemical reactions under evapo-concentration. A multi-species hydrodynamic flow and transport simulation model (SEAWAT) is coupled to a batch reaction model (PHREEQC) to analyze densitydriven flow on islands in the Okavango Delta, Botswana. Evapo-concentration on the islands leads to steadily increasing concentrations until the onset of density-driven flow against the evaporation-induced upward gradient. Lag times to the onset...

  20. Penguin-like Diagrams from the Standard Model

    CERN Document Server

    Chia, Swee-Ping

    2015-01-01

    The Standard Model is highly successful in describing the interactions of leptons and quarks. There are, however, rare processes that involve higher order effects in electroweak interactions. One specific class of processes is the penguin-like diagram. Such class of diagrams involves the neutral change of quark flavours accompanied by the emission of a gluon (gluon penguin), a photon (photon penguin), a gluon and a photon (gluon-photon penguin), a Z-boson (Z penguin), or a Higgs-boson (Higgs penguin). Such diagrams do not arise at the tree level in the Standard Model. They are, however, induced by one-loop effects. In this paper, we present an exact calculation of the penguin diagram vertices in the tHooft-Feynman gauge. Renormalization of the vertex is effected by a prescription by Chia and Chong which gives an expression for the counter term identical to that obtained by employing Ward-Takahashi identity. The on-shell vertex functions for the penguin diagram vertices are obtained. The various penguin diagra...