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Sample records for process flow diagram

  1. Modeling process flow using diagrams

    OpenAIRE

    Kemper, B.; Mast, J.; Mandjes, M.

    2010-01-01

    In the practice of process improvement, tools such as the flowchart, the value-stream map (VSM), and a variety of ad hoc variants of such diagrams are commonly used. The purpose of this paper is to present a clear, precise, and consistent framework for the use of such flow diagrams in process improvement projects. The paper finds that traditional diagrams, such as the flowchart, the VSM, and OR-type of diagrams, have severe limitations, miss certain elements, or are based on implicit but cons...

  2. Process Flow Diagrams for Training and Operations

    Science.gov (United States)

    Venter, Jacobus

    This paper focuses on the use of process flow diagrams for training first responders who execute search and seizure warrants at electronic crime scenes. A generic process flow framework is presented, and the design goals and layout characteristics of process flow diagrams are discussed. An evaluation of the process flow diagrams used in training courses indicates that they are beneficial to first responders performing searches and seizures, and they speed up investigations, including those conducted by experienced personnel.

  3. 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

  4. Quantifying the implicit process flow abstraction in SBGN-PD diagrams with Bio-PEPA

    CERN Document Server

    Loewe, Laurence; Hillston, Jane

    2009-01-01

    For a long time biologists have used visual representations of biochemical networks to gain a quick overview of important structural properties. Recently SBGN, the Systems Biology Graphical Notation, has been developed to standardise the way in which such graphical maps are drawn in order to facilitate the exchange of information. Its qualitative Process Diagrams (SBGN-PD) are based on an implicit Process Flow Abstraction (PFA) that can also be used to construct quantitative representations, which can be used for automated analyses of the system. Here we explicitly describe the PFA that underpins SBGN-PD and define attributes for SBGN-PD glyphs that make it possible to capture the quantitative details of a biochemical reaction network. We implemented SBGNtext2BioPEPA, a tool that demonstrates how such quantitative details can be used to automatically generate working Bio-PEPA code from a textual representation of SBGN-PD that we developed. Bio-PEPA is a process algebra that was designed for implementing quant...

  5. ProofFlow: Flow Diagrams for Proofs

    OpenAIRE

    Kieffer, Steven A.

    2012-01-01

    We present a light formalism for proofs that encodes their inferential structure, along with a system that transforms these representations into flow-chart diagrams. Such diagrams should improve the comprehensibility of proofs. We discuss language syntax, diagram semantics, and our goal of building a repository of diagrammatic representations of proofs from canonical mathematical literature. The repository will be available online in the form of a wiki at proofflow.org, wher...

  6. Formalization of the Data Flow Diagram Rules for Consistency Check

    Directory of Open Access Journals (Sweden)

    Rosziati Ibrahim

    2010-10-01

    Full Text Available In system development life cycle (SDLC, a system model can be developed using Data Flow Diagram(DFD. DFD is graphical diagrams for specifying, constructing and visualizing the model of a system.DFD is used in defining the requirements in a graphical view. In this paper, we focus on DFD and itsrules for drawing and defining the diagrams. We then formalize these rules and develop the tool based onthe formalized rules. The formalized rules for consistency check between the diagrams are used indeveloping the tool. This is to ensure the syntax for drawing the diagrams is correct and strictly followed.The tool automates the process of manual consistency check between data flow diagrams.

  7. 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

  8. A Formal Model for Data Flow Diagram Rules

    Directory of Open Access Journals (Sweden)

    Rosziati Ibrahim

    2011-05-01

    Full Text Available A formal model for data flow diagram (DFD rules is developed by introducing a syntax and semantics for its rules. DFD has been chosen because it is an approach for specifying, constructing and visualizing the model of a system graphically and has been in practical use on a very wide basis but still lacks formal and precise understanding. This formal model can be used to check the correctness of the diagrams and consistency among the diagrams.

  9. Recognition and processing of logic diagrams

    Science.gov (United States)

    Darwish, Ahmed M.; Bashandy, Ahmed R.

    1996-03-01

    In this paper we present a vision system that is capable of interpreting schematic logic diagrams, i.e. determine the output as a logic function of the inputs. The system is composed of a number of modules each designed to perform a specific subtask. Each module bears a minor contribution in the form of a new mixture of known algorithms or extensions to handle actual real life image imperfections which researchers tend to ignore when they develop their theoretical foundations. The main contribution, thus, is not in any individual module, it is rather in their integration to achieve the target job. The system is organized more or less in a classical fashion. Aside from the image acquisition and preprocessing modules, interesting modules include: the segmenter, the identifier, the connector and the grapher. A good segmentation output is one reason for the success of the presented system. Several novelties exist in the presented approach. Following segmentation the type of each logic gate is determined and its topological connectivity. The logic diagram is then transformed to a directed acyclic graph in which the final node is the output logic gate. The logic function is then determined by backtracking techniques. The system is not only aimed at recognition applications. In fact its main usage may be to target other processing applications such as storage compression and graphics modification and manipulation of the diagram as is explained.

  10. The Delunification Process and Minimal Diagrams

    OpenAIRE

    Jablan, Slavik; Kauffman, Louis; Lopes, Pedro

    2014-01-01

    A link diagram is said to be lune-free if, when viewed as a 4-regular plane graph it does not have multiple edges between any pair of nodes. We prove that any colored link diagram is equivalent to a colored lune-free diagram with the same number of colors. Thus any colored link diagram with a minimum number of colors (known as a minimal diagram) is equivalent to a colored lune-free diagram with that same number of colors. We call the passage from a link diagram to an equival...

  11. 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…

  12. AUTO-LAY: automatic layout generation for procedure flow diagrams

    International Nuclear Information System (INIS)

    Nuclear Power Plant Procedures can be seen from essentially two viewpoints: the process and the information management. From the first point of view, it is important to supply the knowledge apt to solve problems connected with the control of the process, from the second one the focus of attention is on the knowledge representation, its structure, elicitation and maintenance, formal quality assurance. These two aspects of procedure representation can be considered and solved separately. In particular, methodological, formal and management issues require long and tedious activities, that in most cases constitute a great barrier for procedures development and upgrade. To solve these problems, Ansaldo is developing DIAM, a wide integrated tool for procedure management to support in procedure writing, updating, usage and documentation. One of the most challenging features of DIAM is AUTO-LAY, a CASE sub-tool that, in a complete automatical way, structures parts or complete flow diagrams. This is a feature that is partially present in some other CASE products, that, anyway, do not allow complex graph handling and isomorphism between video and paper representation AUTO-LAY has the unique prerogative to draw graphs of any complexity, to section them in pages, and to automatically compose a document. This has been recognized in the literature as the most important second-generation CASE improvement. (author). 5 refs., 9 figs

  13. 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...

  14. Data Flow Sequences: A Revision of Data Flow Diagrams for Modelling Applications using XML

    Directory of Open Access Journals (Sweden)

    James PH Coleman

    2013-06-01

    Full Text Available Data Flow Diagrams were developed in the 1970’s as a method of modelling data flow when developing information systems. While DFDs are still being used, the modern web-based which is client-server based means that DFDs are not as useful. This paper proposes a modified form of DFD that incorporates, amongst other features sequences. The proposed system, called Data Flow Sequences (DFS is better able to model real world systems in a way that simplifies application development. The paper also proposes an XML implementation for DFS which allows analytical tools to be used to analyse the DFS diagrams. The paper discusses a tool that is able to detect orphan data flow sequences and other potential problems.

  15. Microsoft Visio 2013 business process diagramming and validation

    CERN Document Server

    Parker, David

    2013-01-01

    Microsoft Visio 2013 Business Process Diagramming and Validation provides a comprehensive and practical tutorial including example code and demonstrations for creating validation rules, writing ShapeSheet formulae, and much more.If you are a Microsoft Visio 2013 Professional Edition power user or developer who wants to get to grips with both the essential features of Visio 2013 and the validation rules in this edition, then this book is for you. A working knowledge of Microsoft Visio and optionally .NET for the add-on code is required, though previous knowledge of business process diagramming

  16. 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.

  17. 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.

  18. Reporting of participant flow diagrams in published reports of randomized trials

    OpenAIRE

    Hopewell Sally; Hirst Allison; Collins Gary S; Mallett Sue; Yu Ly-Mee; Altman Douglas G

    2011-01-01

    Abstract Background Reporting of the flow of participants through each stage of a randomized trial is essential to assess the generalisability and validity of its results. We assessed the type and completeness of information reported in CONSORT (Consolidated Standards of Reporting Trials) flow diagrams published in current reports of randomized trials. Methods A cross sectional review of all primary reports of randomized trials which included a CONSORT flow diagram indexed in PubMed core clin...

  19. 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

  20. Merging Object and Process Diagrams for Business Information Modeling

    CERN Document Server

    Chénais, 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 process modeling to achieve a necessary transparency. We will finally present a modeling tool we developed which, using pilot case studies, helps to show some of the advantages of a dual model approach.

  1. 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)

  2. Reporting of participant flow diagrams in published reports of randomized trials

    Directory of Open Access Journals (Sweden)

    Hopewell Sally

    2011-12-01

    Full Text Available Abstract Background Reporting of the flow of participants through each stage of a randomized trial is essential to assess the generalisability and validity of its results. We assessed the type and completeness of information reported in CONSORT (Consolidated Standards of Reporting Trials flow diagrams published in current reports of randomized trials. Methods A cross sectional review of all primary reports of randomized trials which included a CONSORT flow diagram indexed in PubMed core clinical journals (2009. We assessed the proportion of parallel group trial publications reporting specific items recommended by CONSORT for inclusion in a flow diagram. Results Of 469 primary reports of randomized trials, 263 (56% included a CONSORT flow diagram of which 89% (237/263 were published in a CONSORT endorsing journal. Reports published in CONSORT endorsing journals were more likely to include a flow diagram (62%; 237/380 versus 29%; 26/89. Ninety percent (236/263 of reports which included a flow diagram had a parallel group design, of which 49% (116/236 evaluated drug interventions, 58% (137/236 were multicentre, and 79% (187/236 compared two study groups, with a median sample size of 213 participants. Eighty-one percent (191/236 reported the overall number of participants assessed for eligibility, 71% (168/236 the number excluded prior to randomization and 98% (231/236 the overall number randomized. Reasons for exclusion prior to randomization were more poorly reported. Ninety-four percent (223/236 reported the number of participants allocated to each arm of the trial. However, only 40% (95/236 reported the number who actually received the allocated intervention, 67% (158/236 the number lost to follow up in each arm of the trial, 61% (145/236 whether participants discontinued the intervention during the trial and 54% (128/236 the number included in the main analysis. Conclusions Over half of published reports of randomized trials included a diagram showing the flow of participants through the trial. However, information was often missing from published flow diagrams, even in articles published in CONSORT endorsing journals. If important information is not reported it can be difficult and sometimes impossible to know if the conclusions of that trial are justified by the data presented.

  3. Flow regimes and phase diagram of inertial particle suspensions

    CERN Document Server

    Lashgari, Iman; Breugem, Wim-Paul; Brandt, Luca

    2014-01-01

    The aim of this Letter is to characterize the flow regimes of suspensions of finite-size solid particles in a viscous fluid at finite inertia. We explore the system behavior as function of the particle volume fraction and the Reynolds number (the ratio of flow and particle inertia to viscous forces). Unlike single phase flows where a clear distinction exists between the laminar and the turbulent regime, three different states can be identified in the presence of a particulate phase, with smooth transitions between them. At low volume fractions, the flow becomes turbulent when increasing the Reynolds number, transitioning from the laminar regime dominated by viscous forces to the turbulent regime characterized by enhanced momentum transport by turbulent eddies. At larger volume fractions, we identify a new state characterized by an even larger increase of the wall friction. The wall friction increases with the Reynolds number (inertial effects) while the turbulent transport is unaffected, as in a state of inte...

  4. Derivation of a Fundamental Diagram for Urban Traffic Flow

    OpenAIRE

    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 curves. Here, we derive expected fundamental relationships from a model of traffic flows at intersections, which suggest that the recently measured f...

  5. Phase Diagrams and Fluid Properties of H2O-NaCl for Flow Simulations

    Science.gov (United States)

    Driesner, T.

    2011-12-01

    The system H2O-NaCl is the simplest proxy to saline fluids in the earth's crust. Such fluids play a central role in processes ranging from basinal fluid flow through hydrothermal heat transport along mid-ocean ridges to ore formation in magmatic-hydrothemal systems. Addition of NaCl strongly modifies the phase diagram of water (Driesner & Heinrich, 2007). The temperature-pressure conditions of vapor+liquid coexistence are greatly enlarged, and new phase regions of vapor+salt, liquid+salt, and vapor+liquid+salt are encountered. High contrasts in salinity, density and viscosity of vapor and liquid have profound effects on fluid flow in hydrothermal convection. Flow simulations of H2O-NaCl can be performed by choosing enthalpy, pressure and salinity as state variables. Temperature, pressure and salinity can be chosen as well and require iteration until thermal equilibrium between rock and fluid is reached. Carefully accounting for numerical precision issues and steep gradients is key to make such iterations work routinely. Two- and three-phase adiabatic compressibilities need to be employed if strict consistency of the scheme is required and to avoid singularities along the pure water boiling curve. The general setup of a numerical scheme as well as applications to natural examples will be shown. Driesner, T., and Heinrich, C.A. (2007),Geochimica et Cosmochimica Acta 71, 4880-4901.

  6. 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…

  7. 18 CFR 260.8 - System flow diagrams: Format No. FERC 567.

    Science.gov (United States)

    2010-04-01

    ... REGULATORY COMMISSION, DEPARTMENT OF ENERGY APPROVED FORMS, NATURAL GAS ACT STATEMENTS AND REPORTS (SCHEDULES) § 260.8 System flow diagrams: Format No. FERC 567. (a) Each Major natural gas pipeline company, having a.... For purposes of system peak deliveries, the heating season overlapping the year's end shall be...

  8. Applying state diagrams to food processing and development

    Science.gov (United States)

    Roos, Y.; Karel, M.

    1991-01-01

    The physical state of food components affects their properties during processing, storage, and consumption. Removal of water by evaporation or by freezing often results in formation of an amorphous state (Parks et al., 1928; Troy and Sharp, 1930; Kauzmann, 1948; Bushill et al., 1965; White and Cakebread, 1966; Slade and Levine, 1991). Amorphous foods are also produced from carbohydrate melts by rapid cooling after extrusion or in the manufacturing of hard sugar candies and coatings (Herrington and Branfield, 1984). Formation of the amorphous state and its relation to equilibrium conditions are shown in Fig. 1 [see text]. The most important change, characteristic of the amorphous state, is noticed at the glass transition temperature (Tg), which involves transition from a solid "glassy" to a liquid-like "rubbery" state. The main consequence of glass transition is an increase of molecular mobility and free volume above Tg, which may result in physical and physico-chemical deteriorative changes (White and Cakebread, 1966; Slade and Levine, 1991). We have conducted studies on phase transitions of amorphous food materials and related Tg to composition, viscosity, stickiness, collapse, recrystallization, and ice formation. We have also proposed that some diffusion-limited deteriorative reactions are controlled by the physical state in the vicinity of Tg (Roos and Karel, 1990, 1991a, b, c). The results are summarized in this article, with state diagrams based on experimental and calculated data to characterize the relevant water content, temperature, and time-dependent phenomena of amorphous food components.

  9. Enhanced empirical data for the fundamental diagram and the flow through bottlenecks

    CERN Document Server

    Seyfried, A; Kähler, J; Klingsch, W; Portz, A; Rupprecht, T; Schadschneider, A; Steffen, B; Winkens, A

    2008-01-01

    In recent years, several approaches for modelling pedestrian dynamics have been proposed and applied e.g. for design of egress routes. However, so far not much attention has been paid to their 'quantitative' validation. This unsatisfactory situation belongs amongst others on the uncertain and contradictory experimental data base. The fundamental diagram, i.e. the density-dependence of the flow or velocity, is probably the most important relation as it connects the basic parameter to describe the dynamic of crowds. But specifications in different handbooks as well as experimental measurements differ considerably. The same is true for the bottleneck flow. After a comprehensive review of the experimental data base we give an survey of a research project, including experiments with up to 250 persons performed under well controlled laboratory conditions. The trajectories of each person are measured in high precision to analyze the fundamental diagram and the flow through bottlenecks. The trajectories allow to stud...

  10. Using Sankey diagrams to map energy flow from primary fuel to end use

    International Nuclear Information System (INIS)

    Highlights: • Energy flows from both supply and demand sides shown through Sankey diagrams. • Energy flows from reserves to energy end uses for primary and secondary fuels shown. • Five main energy demand sectors in Alberta are analyzed. • In residential/commercial sectors, highest energy consumption is in space heating. • In the industrial sector, highest energy use is in the mining subsector. - Abstract: The energy sector is the largest contributor to gross domestic product (GDP), income, employment, and government revenue in both developing and developed nations. But the energy sector has a significant environmental footprint due to greenhouse gas (GHG) emissions. Efficient production, conversion, and use of energy resources are key factors for reducing the environmental footprint. Hence it is necessary to understand energy flows from both the supply and the demand sides. Most energy analyses focus on improving energy efficiency broadly without considering the aggregate energy flow. We developed Sankey diagrams that map energy flow for both the demand and supply sides for the province of Alberta, Canada. The diagrams will help policy/decision makers, researchers, and others to understand energy flow from reserves through to final energy end uses for primary and secondary fuels in the five main energy demand sectors in Alberta: residential, commercial, industrial, agricultural, and transportation. The Sankey diagrams created for this study show total energy consumption, useful energy, and energy intensities of various end-use devices. The Long-range Energy Alternatives Planning System (LEAP) model is used in this study. The model showed that Alberta’s total input energy in the five demand sectors was 189 PJ, 186 PJ, 828.5PJ, 398 PJ, and 50.83 PJ, respectively. On the supply side, the total energy input and output were found to be 644.84 PJ and 239 PJ, respectively. These results, along with the associated energy flows were depicted pictorially using Sankey diagrams. The Sankey diagrams reveal the current efficiencies within various end-use sectors and could help identify options for improving energy efficiency in order to reduce GHG emissions

  11. 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...

  12. Interpreting Evolutionary Diagrams: When Topology and Process Conflict

    Science.gov (United States)

    Catley, Kefyn M.; Novick, Laura R.; Shade, Courtney K.

    2010-01-01

    The authors argue that some diagrams in biology textbooks and the popular press presented as depicting evolutionary relationships suggest an inappropriate (anagenic) conception of evolutionary history. The goal of this research was to provide baseline data that begin to document how college students conceptualize the evolutionary relationships…

  13. Urbaryon diagrams and selection rule of weak non-leptonic processes

    International Nuclear Information System (INIS)

    Weak decay processes of kaons and charmed pseudo-scalar mesons are analysed by using urbaryon diagrams assuming current-current interaction. The relation between the diagrams and the possible selection rule (?nsub(t)=0 rule) are discussed and sum rules for charmed meson decays are given. Crucial test for our approach is also presented. (auth.)

  14. Scale Setting in QCD and the Momentum Flow in Feynman Diagrams

    OpenAIRE

    Neubert, Matthias

    1994-01-01

    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...

  15. Traveling wave solution of higher-order traffic flow model with discontinuous fundamental diagram

    Science.gov (United States)

    Wu, Chun-Xiu

    2015-07-01

    The traveling wave solution of a unified higher-order traffic flow model is investigated with a discontinuous fundamental diagram under the Lagrange coordinate. The equilibrium velocity is a piecewise function which consists of two concave functions. The weak solution theory is applied to study the traveling wave solution of the model, in which a set of equations about the characteristic parameters are obtained. Through numerical simulation, the moving cluster solutions of the anisotropic and isotropic traffic flow models are reproduced, respectively. The numerical results agree with the analytical ones.

  16. Merging Object and Process Diagrams for Business Information Modeling

    OpenAIRE

    Chénais, 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...

  17. Flow Logic for Process Calculi

    DEFF Research Database (Denmark)

    Nielson, Hanne Riis; Nielson, Flemming; Pilegaard, Henrik

    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 ...

  18. Evolution of Near-surface Flows Inferred from High-resolution Ring-diagram Analysis

    CERN Document Server

    Bogart, Richard S; Baldner,; Basu, Sarbani

    2015-01-01

    Ring-diagram analysis of acoustic waves observed at the photosphere can provide a relatively robust determination of the sub-surface flows at a particular time under a particular region. The depth of penetration of the waves is related to the size of the region, hence the depth extent of the measured flows is inversely proportional to the spatial resolution. Most ring-diagram analysis has focused on regions of extent ~15{\\deg} (180 Mm) or more in order to provide reasonable mode sets for inversions. HMI data analysis also provides a set of ring fit parameters on a scale three times smaller. These provide flow estimates for the outer 1% (7 Mm) of the Sun only, with very limited depth resolution, but with spatial resolution adequate to map structures potentially associated with the belts and regions of magnetic activity. There are a number of systematic effects affecting the determination of flows from local helioseismic analysis of regions over different parts of the observable disk, not all well understood. I...

  19. 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)

  20. Evolution of Near-surface Flows Inferred from High-resolution Ring-diagram Analysis

    Science.gov (United States)

    Bogart, Richard S.; Baldner, Charles S.; Basu, Sarbani

    2015-07-01

    Ring-diagram analysis of acoustic waves observed at the photosphere can provide a relatively robust determination of the sub-surface flows at a particular time under a particular region. The depth of penetration of the waves is related to the size of the region, hence the depth extent of the measured flows is inversely proportional to the spatial resolution. Most ring-diagram analysis has focused on regions of extent ?15° (180 Mm) or more in order to provide reasonable mode sets for inversions. Helioseismic and Magnetic Imager (HMI) data analysis also provides a set of ring fit parameters on a scale three times smaller. These provide flow estimates for the outer 1% (7 Mm) of the Sun only, with very limited depth resolution, but with spatial resolution adequate to map structures potentially associated with the belts and regions of magnetic activity. There are a number of systematic effects affecting the determination of flows from a local helioseismic analysis of regions over different parts of the observable disk, and not all of them are well understood. In this study we characterize those systematic effects with higher spatial resolution so that they may be accounted for more effectively in mapping the temporal and spatial evolution of the flows. Leaving open the question of the mean structure of the global meridional circulation and the differential rotation, we describe the near-surface flow anomalies in time and latitude corresponding to the torsional oscillation pattern in differential rotation and analogous patterns in the meridional cell structure as observed by the Solar Dynamics Observatory/HMI.

  1. Horizontal Flows in Active Regions from Ring-diagram and Local Correlation Tracking Methods

    CERN Document Server

    Jain, Kiran; Ravindra, B; Komm, R; Hill, F

    2015-01-01

    Continuous high-cadence and high-spatial resolution Dopplergrams allow us to study sub-surface dynamics that may be further extended to explore precursors of visible solar activity on the surface. Since the p-mode power is absorbed in the regions of high magnetic field, the inferences in these regions are often presumed to have large uncertainties. In this paper, using the Dopplergrams from space-borne Helioseismic Magnetic Imager (HMI), we compare horizontal flows in a shear layer below the surface and the photospheric layer in and around active regions. The photospheric flows are calculated using local correlation tracking (LCT) method while the ring-diagram (RD) technique of helioseismology is used to infer flows in the sub-photospheric shear layer. We find a strong positive correlation between flows from both methods near the surface. This implies that despite the absorption of acoustic power in the regions of strong magnetic field, the flows inferred from the helioseismology are comparable to those from ...

  2. Stress/temperature phase diagrams as a tool for shape memory alloy selection and processing

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, N.B.; Friend, C.M. [Cranfield Univ., Swindon, Wilts (United Kingdom). Dept. of Materials and Medical Sciences

    2001-11-01

    One of the difficulties of applying shape memory alloys to real applications is dealing with how applied stress affects the transformation temperatures and phase sequence. This paper presents stress-temperature phase transformation diagrams of the type described by Todoroki, Tamura and Suzuki [1]. The data employed to construct these diagrams relates to a previous study of binary NiTi alloys that have varied alloy compositions, prior cold work and heat treatment temperatures [2]. The diagrams presented in this paper graphically display how phase sequence as well as transformation temperatures vary with processing and alloying parameters. In addition, it is shown that the stress-temperature diagrams change after repeated thermal transformations against applied stress. Increasing M{sub s} temperatures and decreasing A{sub s} temperatures result in narrower thermal hysteresis and loss of the intermediate R-phase. (orig.)

  3. The Mental Health Outcomes of Drought: A Systematic Review and Causal Process Diagram.

    Science.gov (United States)

    Vins, Holly; Bell, Jesse; Saha, Shubhayu; Hess, Jeremy J

    2015-10-01

    Little is understood about the long term, indirect health consequences of drought (a period of abnormally dry weather). In particular, the implications of drought for mental health via pathways such as loss of livelihood, diminished social support, and rupture of place bonds have not been extensively studied, leaving a knowledge gap for practitioners and researchers alike. A systematic review of literature was performed to examine the mental health effects of drought. The systematic review results were synthesized to create a causal process diagram that illustrates the pathways linking drought effects to mental health outcomes. Eighty-two articles using a variety of methods in different contexts were gathered from the systematic review. The pathways in the causal process diagram with greatest support in the literature are those focusing on the economic and migratory effects of drought. The diagram highlights the complexity of the relationships between drought and mental health, including the multiple ways that factors can interact and lead to various outcomes. The systematic review and resulting causal process diagram can be used in both practice and theory, including prevention planning, public health programming, vulnerability and risk assessment, and research question guidance. The use of a causal process diagram provides a much needed avenue for integrating the findings of diverse research to further the understanding of the mental health implications of drought. PMID:26506367

  4. A rigorous semantics for BPMN 2.0 process diagrams

    CERN Document Server

    Kossak, Felix; Geist, Verena; Kubovy, Jan; Natschläger, Christine; Ziebermayr, Thomas; Kopetzky, Theodorich; Freudenthaler, Bernhard; Schewe, Klaus-Dieter

    2015-01-01

    This book provides the most complete formal specification of the semantics of the Business Process Model and Notation 2.0 standard (BPMN) available to date, in a style that is easily understandable for a wide range of readers - not only for experts in formal methods, but e.g. also for developers of modeling tools, software architects, or graduate students specializing in business process management. BPMN - issued by the Object Management Group - is a widely used standard for business process modeling. However, major drawbacks of BPMN include its limited support for organizational modeling, i

  5. When local deformations trigger lattice instability: Flow diagram investigations for photoinduced and quenched metastable states in a Prussian blue analog

    Science.gov (United States)

    Itoi, Miho; Maurin, Isabelle; Varret, François; Frye, Franz A.; Talham, Daniel R.; Chernyshov, Dmitry; Boukheddaden, Kamel

    2013-09-01

    The structural aspects of the metastable states for K0.32Co[Fe(CN)6]0.76·3H2O have been investigated by synchrotron x-ray powder diffraction. The title compound exhibits nonequilibrium high spin (HS) states of CoII(S=3/2)-FeIII(S=1/2) configuration, induced by rapid cooling or photoexcitation from the low-temperature (LT) phase. By introducing a new local order parameter of tilting angle between cyanide-bridged Fe and Co-based octahedra, we discovered the existence of a precursor phenomenon triggering the collective instability during the thermal relaxation of the photoexcited (PX) state. Moreover, we introduced a methodology, based on the flow diagram studies, which allowed us to clearly distinguish the obtained metastable states through their strength of spin-lattice coupling, leading to various pathways in the phase space during the combined electroelastic relaxation process.

  6. 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.

  7. 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.

  8. 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

  9. The phase diagram of milk: a new tool for optimising the drying process

    OpenAIRE

    Vuataz, Gilles

    2002-01-01

    The spray-drying process of milk has been developed using an approach based more on empirical and technological concepts than on food material science. However, optimisation of the concentration and spray-drying steps require a detailed consideration of material phase transitions as well as the kinetics of possible chemical reactions and physical transformations. The phase diagram of milk, now completed by a description of glass transition, was found to be a very powerful tool for understandi...

  10. 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.

  11. Two-state shear diagrams for complex fluids in shear flow

    CERN Document Server

    Olmsted, P D

    1999-01-01

    The possible ``phase diagrams'' for shear-induced phase transitions between two phases are collected. We consider shear-thickening and shear-thinning fluids, under conditions of both common strain rate and common stress in the two phases, and present the four fundamental shear stress vs. strain-rate curves and discuss their concentration dependence. We outline how to construct more complicated phase diagrams, discuss in which class various experimental systems fall, and sketch how to reconstruct the phase diagrams from rheological measurements.

  12. Stepwise flow diagram for the development of formulations of non spore-forming bacteria against foliar pathogens: The case of Lysobacter capsici AZ78.

    Science.gov (United States)

    Segarra, Guillem; Puopolo, Gerardo; Giovannini, Oscar; Pertot, Ilaria

    2015-12-20

    The formulation is a significant step in biopesticide development and is an efficient way to obtain consistency in terms of biological control under field conditions. Nonetheless, there is still a lack of information regarding the processes needed to achieve efficient formulation of non spore-forming bacterial biological control agents. In response to this, we propose a flow diagram made up of six steps including selection of growth parameters, checking of minimum shelf life, selection of protective additives, checking that the additives have no adverse effects, validation of the additive mix under field conditions and choosing whether to use additives as co-formulants or tank mix additives. This diagram is intended to provide guidance and decision-making criteria for the formulation of non spore-forming bacterial biological control agents against foliar pathogens. The diagram was then validated by designing an efficient formulation for a Gram-negative bacterium, Lysobacter capsici AZ78, to control grapevine downy mildew caused by Plasmopara viticola. A harvest of 10(10)L. capsici AZ78cellsml(-1) was obtained in a bench top fermenter. The viability of cells decreased by only one order of magnitude after one year of storage at 4°C. The use of a combination of corn steep liquor, lignosulfonate, and polyethyleneglycol in the formulation improved the survival of L. capsici AZ78 cells living on grapevine leaves under field conditions by one order of magnitude. Furthermore, the use of these additives also guaranteed a reduction of 71% in P. viticola attacks. In conclusion, this work presents a straightforward stepwise flow diagram to help researchers develop formulations for biological control agents that are easy to prepare, stable, not phytotoxic and able to protect the microorganims under field conditions. PMID:26467716

  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. 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 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.)

  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. The use of UML activity diagrams and the i* language in the modeling of the balanced scorecard implantation process

    OpenAIRE

    Haya, Mariela; Franch, Xavier; Mayol, Enric

    2005-01-01

    Business management is a complex task that can be facilitated using different methodologies and models. One of their most relevant purposes is to align the organization strategy with the daily functioning of the organization. One of these models is the Balanced Scorecard (BSC). In this paper, we propose a modeling strategy for the BSC implantation process. We will model it using UML Activity Diagrams and Strategy Dependency models of the language i*. The Activity Diagrams allow determining th...

  17. Chemical reactions and processes under flow conditions

    CERN Document Server

    Luis, Santiago V; Clark, James H

    2009-01-01

    Pharmaceutical and fine chemical products are typically synthesised batchwise which is an anomaly since batch processes have a series of practical and economical disadvantages. On the contrary, flow continuous processes present a series of advantages leading to new ways to synthesise chemical products. Flow processes - * enable control reaction parameters more precisely (temperature, residence time, amount of reagents and solvent etc.), leading to better reproducibility, safer and more reliable processes * can be performed more advantageously using immobilized reagents or catalysts * improve t

  18. Microstructure of Model Emulsion in Process Flow.

    Czech Academy of Sciences Publication Activity Database

    Preziosi, V.; K?iš?ál, Ji?í; Simoncelli, A.; Guido, S.

    Napoli : -, 2011, s. 43. ISBN 978-88-89677-22-3. [International Conference on Multiphase Flow in Industrial Plants /12./. Ischia, Napoli (IT), 21.09.2011-23.09.2011] Institutional research plan: CEZ:AV0Z40720504 Keywords : microstructure * emulsion * process flow Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  19. Solvable phase diagrams and ensemble inequivalence for two-dimensional and geophysical turbulent flows

    OpenAIRE

    Venaille, Antoine; Bouchet, Freddy

    2010-01-01

    Using explicit analytical computations, generic occurrence of inequivalence between two or more statistical ensembles is obtained for a large class of equilibrium states of two-dimensional and geophysical turbulent flows. The occurrence of statistical ensemble inequivalence is shown to be related to previously observed phase transitions in the equilibrium flow topology. We find in these turbulent flow equilibria, two mechanisms for the appearance of ensemble equivalences, th...

  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. 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

  2. Learning with Diagrams.

    Science.gov (United States)

    Henderson, Garry

    1999-01-01

    Argues that diagram interpretation is largely text-dependent and is also dependent upon the use of particular diagram-processing skills which may be very difficult to develop. Discusses some interpretation difficulties and advances strategies to help teachers make more effective use of diagrams. (Contains 20 references.) (Author/WRM)

  3. Solvable phase diagrams and ensemble inequivalence for two-dimensional and geophysical turbulent flows

    CERN Document Server

    Venaille, Antoine

    2010-01-01

    Using explicit analytical computations, generic occurrence of inequivalence between two or more statistical ensembles is obtained for a large class of equilibrium states of two-dimensional and geophysical turbulent flows. The occurrence of statistical ensemble inequivalence is shown to be related to previously observed phase transitions in the equilibrium flow topology. We find in these turbulent flow equilibria, two mechanisms for the appearance of ensemble equivalences, that were not observed in any physical systems before. These mechanisms are associated respectively with second-order azeotropy (simultaneous appearance of two second-order phase transitions), and with bicritical points (bifurcation from a first-order to two second-order phase transition lines). The important roles of domain geometry, of topography, and of a screening length scale (the Rossby radius of deformation) are discussed. It is found that decreasing the screening length scale (making interactions more local) surprisingly widens the r...

  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. Introduction to Feynman diagrams

    CERN Document Server

    Bilenky, S M

    2013-01-01

    Introduction to Feynman Diagrams provides Feynman diagram techniques and methods for calculating quantities measured experimentally. The book discusses topics Feynman diagrams intended for experimental physicists. Topics presented include methods for calculating the matrix elements (by perturbation theory) and the basic rules for constructing Feynman diagrams; techniques for calculating cross sections and polarizations; processes in which both leptons and hadrons take part; and the electromagnetic and weak form factors of nucleons. Experimental physicists and graduate students of physics will

  6. Introduction to Feynman diagrams

    CERN Document Server

    Bilenky, Samoil Mikhelevich

    1974-01-01

    Introduction to Feynman Diagrams provides Feynman diagram techniques and methods for calculating quantities measured experimentally. The book discusses topics Feynman diagrams intended for experimental physicists. Topics presented include methods for calculating the matrix elements (by perturbation theory) and the basic rules for constructing Feynman diagrams; techniques for calculating cross sections and polarizations; processes in which both leptons and hadrons take part; and the electromagnetic and weak form factors of nucleons. Experimental physicists and graduate students of physics will

  7. Solvable Phase Diagrams and Ensemble Inequivalence for Two-Dimensional and Geophysical Turbulent Flows

    Science.gov (United States)

    Venaille, Antoine; Bouchet, Freddy

    2011-04-01

    Using explicit analytical computations, generic occurrence of inequivalence between two or more statistical ensembles is obtained for a large class of equilibrium states of two-dimensional and geophysical turbulent flows. The occurrence of statistical ensemble inequivalence is shown to be related to previously observed phase transitions in the equilibrium flow topology. We find in these turbulent flow equilibria, two mechanisms for the appearance of ensemble equivalences, that were not observed in any physical systems before. These mechanisms are associated respectively with second-order azeotropy (simultaneous appearance of two second-order phase transitions), and with bicritical points (bifurcation from a first-order to two second-order phase transition lines). The important roles of domain geometry, of topography, and of a screening length scale (the Rossby radius of deformation) are discussed. It is found that decreasing the screening length scale (making interactions more local) surprisingly widens the range of parameters associated with ensemble inequivalence. These results are then generalized to a larger class of models, and applied to a complete description of an academic model for inertial oceanic circulation, the Fofonoff flow.

  8. Probing the QCD phase diagram with measurements of strange hadron elliptic flow in STAR

    CERN Document Server

    ,

    2015-01-01

    We present the measurements of strange hadron elliptic flow at mid-rapidity in Au + Au collisions at $\\sqrt{s_{NN}}$ = 7.7 - 200 GeV using the STAR detector in the years 2010 and 2011. The transverse momentum and collision centrality dependence of elliptic flow is presented. At the intermediate transverse momentum $\\Omega$ baryon and $\\phi$-meson show baryon-meson separation effect similar to proton and pion for minimum-bias Au+Au collision at $\\sqrt{s_{NN}}$ =200 GeV. This indicates formation of collective flow at the early partonic phase. The separation between baryons and mesons at intermediate transverse momentum decreases with decrease in beam energy and almost disappears at $\\sqrt{s_{NN}}$ $\\leq$ 11.5 GeV, indicating hadronic interaction being dominant at the lower beam energy. We observe difference in elliptic flow between particle and anti-particle and this increases with decrease in beam energy. Differences are larger for baryons than mesons. Relative difference between particle and anti-particle ell...

  9. 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.

  10. Cognitive Processes (Probably Stimulated By Using Digital Game "Dynamic Metabolic Diagram Virtual Krebs´ Cycle"

    Directory of Open Access Journals (Sweden)

    A. M. P Azevedo

    2006-07-01

    Full Text Available This work describes some of the possible cognitive operations related to the use of an educational game type activity, which  is  part  of  the  software  e-metabolismo,  developed  to  improve  biochemical  learning.  This  interactive  activity, called  DMDV   – Dynamic  Metabolic  Diagram,  allows  participants  to  drag-and-drop  components  of  the  sequence  of chemical  reactions,  which describe  the  metabolic  route  under study.  It  also offers  to the students  quizzes  and texts about  the  subject.  The  suggestion  of  cognitive  processes  possibly  triggered  by  the  software,  which  must  improve effective learning, was based on Jean Piaget’s genetic epistemological ideas to explain the cognitive activity. One of these  processes  is  the  mere  act  of  playing  the  game,  which  Piaget  relates  to  humans  needs  of  learning  rules  of socialization.  It  also  can  be  seen  as  a  first  step  in  cognition  process,  the  so  called  adaptation  function  that  include assimilation and accommodation, interactive processes between intelligent activities and elements from the reality, to became part of the individual´s mental structures. Another example: drag and drop substracts and enzymes pieces in a  virtual  board,  each  one  corresponding  to  an  specific  place  in  a  metabolic  route.  This  operation  can  be  related  to motivation,  an  affective  element  proposed  by  Piaget  to  stimulate  curiosity  and  improve  construction  of  knowledge structures.  Besides  this  issue,  the  act  of  choosing  pieces  is  assumed  to  inform  the  student  previous  knowledge (previous  cognitive  structures,  which,  according  to  Piaget,  must  be  misbalanced  (equilibration  of  new  structures  is supposed to be part of the dynamic process of organization of new knowledge. DMDV was tested with a group of 24 students  (2003  and  another  group  of  36  students  in  2004,  of  a  Biochemistry  Course  regularly  registered  at FFFMCPA´s medicine  faculty.  The  evaluation  of the student’s apprenticeship  was  made  by a  conventional  test  and three Conceptual Maps constructed by each student, (a before playing the game, (b immediately after, and (c three months after the use of the game.

  11. Robust processing of optical flow of fluids.

    Science.gov (United States)

    Doshi, Ashish; Bors, Adrian G

    2010-09-01

    This paper proposes a new approach, coupling physical models and image estimation techniques, for modelling the movement of fluids. The fluid flow is characterized by turbulent movement and dynamically changing patterns which poses challenges to existing optical flow estimation methods. The proposed methodology, which relies on Navier-Stokes equations, is used for processing fluid optical flow by using a succession of stages such as advection, diffusion and mass conservation. A robust diffusion step jointly considering the local data geometry and its statistics is embedded in the proposed framework. The diffusion kernel is Gaussian with the covariance matrix defined by the local second derivatives. Such an anisotropic kernel is able to implicitly detect changes in the vector field orientation and to diffuse accordingly. A new approach is developed for detecting fluid flow structures such as vortices. The proposed methodology is applied on artificially generated vector fields as well as on various image sequences. PMID:20409993

  12. Eviction strategies for semantic flow processing

    OpenAIRE

    Nguyen, M K; Scharrenbach, Thomas; Bernstein, Abraham

    2013-01-01

    In order to cope with the ever-increasing data volume continuous processing of incoming data via Semantic Flow Processing systems have been proposed. These systems allow to answer queries on streams of RDF triples. To achieve this goal they match (triple) patterns against the incoming stream and generate/update variable bindings. Yet, given the continuous nature of the stream the number of bindings can explode and exceed memory; in particular when computing aggregates. To make the information...

  13. Phase diagrams of ionic liquids-based aqueous biphasic systems as a platform for extraction processes

    International Nuclear Information System (INIS)

    Highlights: • Novel ABS based in ionic liquids were determined as a platform for distinct extraction processes. • The effect of pH, IL cation core, alkyl side chain length, IL anion nature, and salt nature on the ABS formation was investigated. • The ability to form ABS increases with the pH and alkyl chain length for all systems studied. • The ILs cation core and anion nature effect on the ABS formation is dominated by the IL (hydrophobic/hydrophilic) nature. • The effect of the different salts depends of the ionic liquid nature and salt valency. - Abstract: In the past few years, ionic liquid-based aqueous biphasic systems have become the subject of considerable interest as a promising technique for the extraction and purification of several macro/biomolecules. Aiming at developing guidelines for more benign and efficient extraction processes, phase diagrams for aqueous biphasic systems composed of ionic liquids and inorganic/organic salts are here reported. Several combinations of ionic liquid families (imidazolium, pyridinium, phosphonium, quaternary ammonium and cholinium) and salts [potassium phosphate buffer (KH2PO4/K2HPO4 at pH 7), potassium citrate buffer (C6H5K3O7/C6H8O7 at pH 5, 6, 7 and 8) and potassium carbonate (K2CO3 at pH ?13)] were evaluated to highlight the influence of the ionic liquid structure (cation core, anion and alkyl chain length), the pH and the salt nature on the formation of aqueous biphasic systems. The binodal curves and respective tie-lines reported for these systems were experimentally determined at (298 ± 1) K. In general, the ability to promote the aqueous biphasic systems formation increases with the pH and alkyl chain length. While the influence of the cation core and anion nature of the ionic liquids on their ability to form aqueous biphasic systems closely correlates with ionic liquids capacity to be hydrated by water, the effect of the different salts depends of the ionic liquid nature and salt valency

  14. Exact and grid-free solutions to the Lighthill-Whitham-Richards traffic flow model with bounded acceleration for a class of fundamental diagrams

    KAUST Repository

    Qiu, Shanwen

    2013-09-01

    In this article, we propose a new exact and grid-free numerical scheme for computing solutions associated with an hybrid traffic flow model based on the Lighthill-Whitham-Richards (LWR) partial differential equation, for a class of fundamental diagrams. In this hybrid flow model, the vehicles satisfy the LWR equation whenever possible, and have a constant acceleration otherwise. We first propose a mathematical definition of the solution as a minimization problem. We use this formulation to build a grid-free solution method for this model based on the minimization of component function. We then derive these component functions analytically for triangular fundamental diagrams, which are commonly used to model traffic flow. We also show that the proposed computational method can handle fixed or moving bottlenecks. A toolbox implementation of the resulting algorithm is briefly discussed, and posted at https://dl.dropbox.com/u/1318701/Toolbox.zip. © 2013 Elsevier Ltd.

  15. Coupling Multiple Stiff Processes in Reactive Flows

    Science.gov (United States)

    Boris, Jay P.; Oran, Elaine S.; Patnaik, Gopal

    1999-11-01

    This paper describes a new, Compenstated Operator-Split (COS) methodology for coupling several distinct, mathematically stiff, reactive flow processes into a dynamic simulation model. Operator-splitting (also called process-splitting or timestep-splitting) is the simplest way to build detailed numerical models containing a number of different reactive flow processes and allows use of optimal algorithms for each of the processes individually [Oran and Boris, 1987]. However, explicit operator-splitting performs poorly in situations where two or more of the processes are ``stiff'' and thus require unacceptably small timesteps. Global implicit coupling can in principle be used for these cases, but the computational cost becomes prohibitive, the programming is often complex, there are serious algorithmic restrictions, and the accuracy can be quite low. We describe how operator-splitting can be extended to a broad class of problems with interacting stiff processes without the limitations of a global implicit framework. (Work Sponsored by ONR through the Naval Research Laboratory.)

  16. 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)

  17. Bidirectional pedestrian fundamental diagram

    OpenAIRE

    Flötteröd, Gunnar; Lämmel, Gregor

    2015-01-01

    This article presents a new model of stationary bidirectional pedestrian flow. Starting out from microscopic first principles, a bidirectional fundamental diagram (FD) is derived that defines direction-specific flow rates as functions of direction-specific densities. The FD yields non-negative and bounded flows and guarantees that the instantaneous density changes that would result from these flows stay bounded between zero and jam density. In its minimal configuration, it uses just as many p...

  18. 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

  19. 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.

  20. The RiverFish Approach to Business Process Modeling: Linking Business Steps to Control-Flow Patterns

    Science.gov (United States)

    Zuliane, Devanir; Oikawa, Marcio K.; Malkowski, Simon; Alcazar, José Perez; Ferreira, João Eduardo

    Despite the recent advances in the area of Business Process Management (BPM), today’s business processes have largely been implemented without clearly defined conceptual modeling. This results in growing difficulties for identification, maintenance, and reuse of rules, processes, and control-flow patterns. To mitigate these problems in future implementations, we propose a new approach to business process modeling using conceptual schemas, which represent hierarchies of concepts for rules and processes shared among collaborating information systems. This methodology bridges the gap between conceptual model description and identification of actual control-flow patterns for workflow implementation. We identify modeling guidelines that are characterized by clear phase separation, step-by-step execution, and process building through diagrams and tables. The separation of business process modeling in seven mutually exclusive phases clearly delimits information technology from business expertise. The sequential execution of these phases leads to the step-by-step creation of complex control-flow graphs. The process model is refined through intuitive table and diagram generation in each phase. Not only does the rigorous application of our modeling framework minimize the impact of rule and process changes, but it also facilitates the identification and maintenance of control-flow patterns in BPM-based information system architectures.

  1. 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.

  2. 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...

  3. Automation of Feynman diagram evaluations

    International Nuclear Information System (INIS)

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

  4. Real time acquisition, processing, and archiving of Doublet III diagram data employing table driven software

    International Nuclear Information System (INIS)

    This paper describes the diagnostic data acquisition, processing and archiving computer system for the Doublet III fusion research device. This paper's emphasis is mainly on the software, but provides a description of the hardware configuration

  5. Electronic diagrams

    CERN Document Server

    Colwell, Morris A

    1976-01-01

    Electronic Diagrams is a ready reference and general guide to systems and circuit planning and in the preparation of diagrams for both newcomers and the more experienced. This book presents guidelines and logical procedures that the reader can follow and then be equipped to tackle large complex diagrams by recognition of characteristic 'building blocks' or 'black boxes'. The goal is to break down many of the barriers that often seem to deter students and laymen in learning the art of electronics, especially when they take up electronics as a spare time occupation. This text is comprised of nin

  6. Application of ISO22000, failure mode, and effect analysis (FMEA) cause and effect diagrams and pareto in conjunction with HACCP and risk assessment for processing of pastry products.

    Science.gov (United States)

    Varzakas, Theodoros H

    2011-09-01

    The Failure Mode and Effect Analysis (FMEA) model has been applied for the risk assessment of pastry processing. A tentative approach of FMEA application to the pastry industry was attempted in conjunction with ISO22000. Preliminary Hazard Analysis was used to analyze and predict the occurring failure modes in a food chain system (pastry processing plant), based on the functions, characteristics, and/or interactions of the ingredients or the processes, upon which the system depends. Critical Control points have been identified and implemented in the cause and effect diagram (also known as Ishikawa, tree diagram, and fishbone diagram). In this work a comparison of ISO22000 analysis with HACCP is carried out over pastry processing and packaging. However, the main emphasis was put on the quantification of risk assessment by determining the Risk Priority Number (RPN) per identified processing hazard. Storage of raw materials and storage of final products at -18°C followed by freezing were the processes identified as the ones with the highest RPN (225, 225, and 144 respectively) and corrective actions were undertaken. Following the application of corrective actions, a second calculation of RPN values was carried out leading to considerably lower values (below the upper acceptable limit of 130). It is noteworthy that the application of Ishikawa (Cause and Effect or Tree diagram) led to converging results thus corroborating the validity of conclusions derived from risk assessment and FMEA. Therefore, the incorporation of FMEA analysis within the ISO22000 system of a pastry processing industry is considered imperative. PMID:21838557

  7. System studies in PA: Development of process influence diagram (PID) for SFR-1 repository near-field + far-field

    International Nuclear Information System (INIS)

    Scenario development is a key component of the performance assessment (PA) process for radioactive waste disposal, the primary objective being to ensure that all relevant factors associated with the future evolution of the repository system are properly considered in PA. As part of scenario development, a list of features, events and processes (FEPs) are identified and assembled, representing the Process System, with interactions/influences between FEPs incorporated in a Process Influence Diagram (PID). This report documents the technical work conducted between 1997 and the end of 1999 under the Systems Studies Project. The overall objective of this project has been the construction of a PID for the SFR-1 repository (final repository for reactor waste), this PID being the first stage in the identification of scenarios to describe future evolution of this repository. The PIDs discussed in this report have been created using two software applications: existing commercial software (Business Modeller, Infotool AB. Stockholm, Sweden) and, more recently, a newly developed software tool SPARTA (Enviros QuantiSci, Henley, U.K.). Although the focus of this report is on the application of SPARTA to PID development, it is important to document the work carried out prior to SPARTA being available, in order to provide a complete record of the entire SFR-1 PID development effort as well as preserving the context of the multi-year project. Following a description of the different disposal sections of the SFR-1 and the various near-field barriers, the sequential development (i.e. near-field of Silo, BMA, BLA, BTF sections; far-field; integrated near-field + far-field) of the PID for SFR-1 repository system using Business Modeller is described. Owing to the complexity of the repository, in terms of number of both different disposal sections (Silo, BLA, BMA, BTF) and barriers associated with each section, the two-dimensional (2D) PID created for SFR-1 using Business Modeller is visually complex and potentially difficult to interpret. Primarily for this reason, the need for an alternative approach was recognised in 1996 and the decision was taken to develop new software for this purpose. Following a consensus on the specific requirements of the new software, a first version of SPARTA became available towards the end of 1998, with subsequent versions being released during 1999. SPARTA is used to generate a three-dimensional (3D) PID consisting of a series of layers, each underlying layer providing additional (more detailed) information about the Process System. The uppermost layer or diagram may be regarded as a top-level view of the repository system (near-field, far-field and biosphere). In the PID developed for SKI, underlying layers or diagrams often have some physical meaning, e.g. sections of the repository (Silo, BLA, BMA, BTF sections, repository zone), or barriers of a section (e.g. for the Silo - backfill, reinforced shell, porous grout or mortar, waste package). Other layers contain groups of related FEPs, e.g. geochemical FEPs. A total of 95 drawings, typically consisting of 6-8 FEPs each, describe the SFR-1 repository system. The two PIDs developed for the SFR-1 repository provide different representations of the near-field and far-field of the repository system; the first PID being two-dimensional and the later one three-dimensional. Despite the different approaches, the primary objective of constructing each PID has been the same: firstly, to ensure that all FEPs relevant to the future evolution of the repository system are considered, and secondly, that all 'essential' influences are identified so that they may be incorporated in the subsequent modelling of the system's evolution

  8. System studies in PA: Development of process influence diagram (PID) for SFR-1 repository near-field + far-field

    Energy Technology Data Exchange (ETDEWEB)

    Stenhouse, M.J. [Monitor Scientific, LLC, Denver, CO (United States); Miller, W.M.; Chapman, N.A. [QuantiSci Ltd., Melton Mowbray (United Kingdom)

    2001-05-01

    Scenario development is a key component of the performance assessment (PA) process for radioactive waste disposal, the primary objective being to ensure that all relevant factors associated with the future evolution of the repository system are properly considered in PA. As part of scenario development, a list of features, events and processes (FEPs) are identified and assembled, representing the Process System, with interactions/influences between FEPs incorporated in a Process Influence Diagram (PID). This report documents the technical work conducted between 1997 and the end of 1999 under the Systems Studies Project. The overall objective of this project has been the construction of a PID for the SFR-1 repository (final repository for reactor waste), this PID being the first stage in the identification of scenarios to describe future evolution of this repository. The PIDs discussed in this report have been created using two software applications: existing commercial software (Business Modeller, Infotool AB. Stockholm, Sweden) and, more recently, a newly developed software tool SPARTA (Enviros QuantiSci, Henley, U.K.). Although the focus of this report is on the application of SPARTA to PID development, it is important to document the work carried out prior to SPARTA being available, in order to provide a complete record of the entire SFR-1 PID development effort as well as preserving the context of the multi-year project. Following a description of the different disposal sections of the SFR-1 and the various near-field barriers, the sequential development (i.e. near-field of Silo, BMA, BLA, BTF sections; far-field; integrated near-field + far-field) of the PID for SFR-1 repository system using Business Modeller is described. Owing to the complexity of the repository, in terms of number of both different disposal sections (Silo, BLA, BMA, BTF) and barriers associated with each section, the two-dimensional (2D) PID created for SFR-1 using Business Modeller is visually complex and potentially difficult to interpret. Primarily for this reason, the need for an alternative approach was recognised in 1996 and the decision was taken to develop new software for this purpose. Following a consensus on the specific requirements of the new software, a first version of SPARTA became available towards the end of 1998, with subsequent versions being released during 1999. SPARTA is used to generate a three-dimensional (3D) PID consisting of a series of layers, each underlying layer providing additional (more detailed) information about the Process System. The uppermost layer or diagram may be regarded as a top-level view of the repository system (near-field, far-field and biosphere). In the PID developed for SKI, underlying layers or diagrams often have some physical meaning, e.g. sections of the repository (Silo, BLA, BMA, BTF sections, repository zone), or barriers of a section (e.g. for the Silo - backfill, reinforced shell, porous grout or mortar, waste package). Other layers contain groups of related FEPs, e.g. geochemical FEPs. A total of 95 drawings, typically consisting of 6-8 FEPs each, describe the SFR-1 repository system. The two PIDs developed for the SFR-1 repository provide different representations of the near-field and far-field of the repository system; the first PID being two-dimensional and the later one three-dimensional. Despite the different approaches, the primary objective of constructing each PID has been the same: firstly, to ensure that all FEPs relevant to the future evolution of the repository system are considered, and secondly, that all 'essential' influences are identified so that they may be incorporated in the subsequent modelling of the system's evolution.

  9. Fluid flow for chemical and process engineers

    CERN Document Server

    Holland, F

    1995-01-01

    This major new edition of a popular undergraduate text covers topics of interest to chemical engineers taking courses on fluid flow. These topics include non-Newtonian flow, gas-liquid two-phase flow, pumping and mixing. It expands on the explanations of principles given in the first edition and is more self-contained. Two strong features of the first edition were the extensive derivation of equations and worked examples to illustrate calculation procedures. These have been retained. A new extended introductory chapter has been provided to give the student a thorough basis to understand the methods covered in subsequent chapters.

  10. OVERLAND FLOW TREATMENT OF POULTRY PROCESSING WASTEWATER IN COLD CLIMATES

    Science.gov (United States)

    This project evaluates a full-scale wastewater treatment facility emphasizing the overland flow process in northern Indiana, which has a cold climate. The other processes include mechanical pretreatment, a storage lagoon, a lagoon for batch chemical treatment of the overland flow...

  11. A multi-phase flow model for electrospinning process

    OpenAIRE

    Xu Lan; Si Na; Lee Eric Wai Ming; Liu Hong-Ying

    2013-01-01

    An electrospinning process is a multi-phase and multi-physicical process with flow, electric and magnetic fields coupled together. This paper deals with establishing a multi-phase model for numerical study and explains how to prepare for nanofibers and nanoporous materials. The model provides with a powerful tool to controlling over electrospinning parameters such as voltage, flow rate, and others.

  12. Planar diagrams

    International Nuclear Information System (INIS)

    We investigate the planar approximation to field theory through the limit of a large internal symmetry group. This yields an alternative and powerful method to count planar diagrams. Results are presented for cubic and quartic vertices. Quantum mechanics treated in this approximation is shown to be equivalent to a free Fermi gas system. (orig.)

  13. 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 fun...

  14. WCSPH viscosity diffusion processes in vortex flows

    OpenAIRE

    Macia Lang, Fabricio; Sánchez Sánchez, Juan Miguel; Souto Iglesias, Antonio; González Gutierrez, Leo Miguel

    2012-01-01

    The aim of this paper is to clarify the role played by the most commonly used viscous terms in simulating viscous laminar flows using the weakly compressible approach in the context of smooth particle hydrodynamics (WCSPH). To achieve this, Takeda et al. (Prog. Theor. Phys. 1994; 92(5):939–960), Morris et al. (J. Comput. Phys. 1997; 136:214–226) and Monaghan–Cleary–Gingold's (Appl. Math. Model. 1998; 22(12):981–993; Monthly Notices of the Royal Astronomical Society 2005; 365:199–213) viscous ...

  15. 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.

  16. 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.

  17. Numerical simulations of rarefied gas flows in thin film processes:

    OpenAIRE

    Dorsman, R.

    2007-01-01

    Many processes exist in which a thin film is deposited from the gas phase, e.g. Chemical Vapor Deposition (CVD). These processes are operated at ever decreasing reactor operating pressures and with ever decreasing wafer feature dimensions, reaching into the rarefied flow regime. As numerical simulation tools are frequently used to design and improve reactors, there is a need for numerical simulation tools capable of modeling rarefied internal gas flows. To fulfill this need, the Direct...

  18. A multi-phase flow model for electrospinning process

    Directory of Open Access Journals (Sweden)

    Xu Lan

    2013-01-01

    Full Text Available An electrospinning process is a multi-phase and multi-physicical process with flow, electric and magnetic fields coupled together. This paper deals with establishing a multi-phase model for numerical study and explains how to prepare for nanofibers and nanoporous materials. The model provides with a powerful tool to controlling over electrospinning parameters such as voltage, flow rate, and others.

  19. 4D flow mri post-processing strategies for neuropathologies

    Science.gov (United States)

    Schrauben, Eric Mathew

    4D flow MRI allows for the measurement of a dynamic 3D velocity vector field. Blood flow velocities in large vascular territories can be qualitatively visualized with the added benefit of quantitative probing. Within cranial pathologies theorized to have vascular-based contributions or effects, 4D flow MRI provides a unique platform for comprehensive assessment of hemodynamic parameters. Targeted blood flow derived measurements, such as flow rate, pulsatility, retrograde flow, or wall shear stress may provide insight into the onset or characterization of more complex neuropathologies. Therefore, the thorough assessment of each parameter within the context of a given disease has important medical implications. Not surprisingly, the last decade has seen rapid growth in the use of 4D flow MRI. Data acquisition sequences are available to researchers on all major scanner platforms. However, the use has been limited mostly to small research trials. One major reason that has hindered the more widespread use and application in larger clinical trials is the complexity of the post-processing tasks and the lack of adequate tools for these tasks. Post-processing of 4D flow MRI must be semi-automated, fast, user-independent, robust, and reliably consistent for use in a clinical setting, within large patient studies, or across a multicenter trial. Development of proper post-processing methods coupled with systematic investigation in normal and patient populations pushes 4D flow MRI closer to clinical realization while elucidating potential underlying neuropathological origins. Within this framework, the work in this thesis assesses venous flow reproducibility and internal consistency in a healthy population. A preliminary analysis of venous flow parameters in healthy controls and multiple sclerosis patients is performed in a large study employing 4D flow MRI. These studies are performed in the context of the chronic cerebrospinal venous insufficiency hypothesis. Additionally, a double-gated flow acquisition and reconstruction scheme demonstrates respiratory-induced changes in internal jugular vein flow. Finally, a semi-automated intracranial vessel segmentation and flow parameter measurement software tool for fast and consistent 4D flow post-processing analysis is developed, validated, and exhibited an in-vivo.

  20. Phase diagrams

    International Nuclear Information System (INIS)

    The description is presented of binary phase diagrams of titanium alloyed with the following elements: silver, aluminium, arsenic, gold, boron, barium, beryllium, bismuth, carbon, calcium, cadmium, cobalt, chromium, copper, iron, gallium, germanium, hydrogen, hafnium, indium, iridium, potassium, lithium, magnesium, manganese, molybdenum, nitrogen, sodium, niobium, nickel, oxygen, osmium, phosphorus, lead, palladium, platinum, plutonium, rhenium, lanthanium, cerium, preseodymium, neodymium, gadolinium, erbium, terbium, thulium, lutetium, rhodium, ruthenium, scandium, silicon, tin, strontium, tantalum, technetium, thorium, uranium, vanadium, tungsten, yttrium, ytterbium, zinc and zirconium

  1. 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,...

  2. Space Based Multi-level Process Flow and Logistics Analysis

    Directory of Open Access Journals (Sweden)

    Zhou Qiu-Zhong

    2013-01-01

    Full Text Available In order to thoroughly promote the enterprise digital construction and meet the demand of production management, the space based multi-level process data organization model has been put forward. Firstly, according to the practical division situation of enterprise production space, the multi-level organization method of production space has been proposed. Then through analyzing the manufacturing process of the products in different space layers, the space based multi-level process flow idea has been presented. At the same time, the mathematical model and formalized expression of multi-level technological process have been established. Finally, the in-output material flow relationship between different levels process flow units has been analyzed and the source of input object as well as the disposition of the output object of various level process flow units has been put into detailed analysis. At the mean time, particular statistical sum and trace arithmetic are provided so as to profoundly illustrate the essence of manufacturing process in theory. As a result, the models proposed in this study are not only express the manufacturing process flow of the product in an intuitive and clear way, but also satisfy all types of demands of production management.

  3. Stochastic equations, flows and measure-valued processes

    CERN Document Server

    Dawson, Donald A

    2010-01-01

    We first prove some general results on pathwise uniqueness, comparison property and existence of non-negative strong solutions of stochastic equations driven by white noises and Poisson random measures. The results are then used to prove the strong existence of two classes of stochastic flows associated with coalescents with multiple collisions, that is, generalized Fleming-Viot flows and flows of continuous-state branching processes with immigration. One of them unifies the different treatments of three kinds of flows in Bertoin and Le Gall (2005). Two scaling limit theorems for the generalized Fleming-Viot flows are proved, which lead to sub-critical branching immigration superprocesses. {From} those theorems we derive easily a generalization of the limit theorem for finite point motions of the flows in Bertoin and Le Gall (2006).

  4. Information Flow Security in Tree-Manipulating Processes

    OpenAIRE

    Kovács, Máté Amadé

    2014-01-01

    By enterprise workflows and web service technologies data is frequently represented in the form of XML documents. In the same time, these systems are highly security critical, because they may be in control of important processes of organizations, while communicating with external partners over the network. Therefore, this work describes three methods to verify information flow properties of processes manipulating tree-structured data.

  5. Environmental Data Flow Six Sigma Process Improvement Savings Overview

    Energy Technology Data Exchange (ETDEWEB)

    Paige, Karen S [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-05-20

    An overview of the Environmental Data Flow Six Sigma improvement project covers LANL’s environmental data processing following receipt from the analytical laboratories. The Six Sigma project identified thirty-three process improvements, many of which focused on cutting costs or reducing the time it took to deliver data to clients.

  6. Multi-phase Flow Modeling applied to Metallurgical Processes

    OpenAIRE

    Johansen, Stein T.

    2002-01-01

    Multiphase flow models have been improved significantly during the last two decades. Together with the development of more advanced numerical techniques and faster and cheaper computers we now see that computational fluid dynamics (CFD) becomes a powerful tool in predicting the performance of complex industrial processes. In particular the processes faced by the metallurgical industries may serve as examples of such complexity.

  7. 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.

  8. Prediction of hygiene in food processing equipment using flow modelling

    DEFF Research Database (Denmark)

    Friis, Alan; Jensen, Bo Boye Busk

    2002-01-01

    Computational fluid dynamics (CFD) has been applied to investigate the design of closed process equipment with respect to cleanability. The CFD simulations were validated using the standardized cleaning test proposed by the European Hygienic Engineering and Design Group. CFD has been proven as a tool which can be used by manufacturers to facilitate their equipment design for high hygienic standards before constructing any prototypes. The study of hydrodynamic cleanability of closed processing equipment was discussed based on modelling the flow in a valve house, an up-stand and various expansions in tubes. Results show that cleaning can be efficient in complex geometries even when the critical wall shear stress (determined in uni-axial flow) is not exceeded. This renders the need for considerations concerning three-dimensional flow, the degree of turbulence and the type of flow pattern. The controlling factors for cleaning identified were the wall shear stress and the nature and magnitude of recirculation zones present.

  9. On-line sample processing methods in flow analysis

    OpenAIRE

    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 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 withou

  11. A viscous flow analysis for the tip vortex generation process

    Science.gov (United States)

    Shamroth, S. J.; Briley, W. R.

    1979-01-01

    A three dimensional, forward-marching, viscous flow analysis is applied to the tip vortex generation problem. The equations include a streamwise momentum equation, a streamwise vorticity equation, a continuity equation, and a secondary flow stream function equation. The numerical method used combines a consistently split linearized scheme for parabolic equations with a scalar iterative ADI scheme for elliptic equations. The analysis is used to identify the source of the tip vortex generation process, as well as to obtain detailed flow results for a rectangular planform wing immersed in a high Reynolds number free stream at 6 degree incidence.

  12. Automatic Test case Generation from UML Activity Diagrams

    Directory of Open Access Journals (Sweden)

    V.Mary Sumalatha*1

    2014-05-01

    Full Text Available Test Case Generation is an important phase in software development. Nowadays much of the research is done on UML diagrams for generating test cases. Activity diagrams are different from flow diagrams in the fact that activity diagrams express parallel behavior which flow diagrams cannot express. This paper concentrates on UML 2.0 Activity Diagram for generating test cases. Fork and join pair in activity diagram are used to represent concurrent activities. A novel method is proposed to generate test case for concurrent and non concurrent activities. Proposed approach details about the importance of concurrent nodes and their execution order in path generation.

  13. Krohne Flow Indicator and High Flow Alarm - Local Indicator and High Flow Alarm of Helium Flow from the SCHe Purge Lines C and D to the Process Vent

    International Nuclear Information System (INIS)

    Flow Indicators/alarms FI/FSH-5*52 and -5*72 are located in the process vent lines connected to the 2 psig SCHe purge lines C and D. They monitor the flow from the 2 psig SCHe purge going to the process vent. The switch/alarm is non-safety class GS

  14. 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.

  15. Causal diagrams for physical models

    CERN Document Server

    Kinsler, Paul

    2015-01-01

    I present a scheme of drawing causal diagrams based on physically motivated mathematical models expressed in terms of temporal differential equations. They provide a means of better understanding the processes and causal relationships contained within such systems.

  16. Elements of flow and diffusion processes in separation nozzles

    International Nuclear Information System (INIS)

    The present monograph is an attempt to systematize the results of studies performed by the author and his colleagues on the physics of the separation nozzle process, which is based on pressure diffusion in curved flows of uranium hexafluoride and a light auxiliary gas. The description of the complex flow and diffusion in separation nozzles includes transient separation effects in ternary mixtures of gases, as well as non-equilibrium phenomena typical of low-density flows of disparate mass mixtures. In addition, the principles and designs of the most important types of separation nozzles are explained in detail. In view of the practical application of the separation nozzle process, general correlations are pointed out between the physics of aerodynamic separation and the technical expenditure for large-scale production of enriched uranium. (orig./WL)

  17. Plant uprooting by flow as a fatigue mechanical process

    Science.gov (United States)

    Perona, Paolo; Edmaier, Katharina; Crouzy, Benoît

    2015-04-01

    In river corridors, plant uprooting by flow mostly occurs as a delayed process where flow erosion first causes root exposure until residual anchoring balances hydrodynamic forces on the part of the plant that is exposed to the stream. Because a given plant exposure time to the action of the stream is needed before uprooting occurs (time-to-uprooting), this uprooting mechanism has been denominated Type II, in contrast to Type I, which mostly affect early stage seedlings and is rather instantaneous. In this work, we propose a stochastic framework that describes a (deterministic) mechanical fatigue process perturbed by a (stochastic) process noise, where collapse occurs after a given exposure time. We test the model using the experimental data of Edmaier (2014) and Edmaier et al. (submitted), who investigated vegetation uprooting by flow in the limit of low plant stem-to-sediment size ratio by inducing parallel riverbed erosion within an experimental flume. We first identify the proper timescale and lengthscale for rescaling the model. Then, we show that it describes well all the empirical cumulative distribution functions (cdf) of time-to-uprooting obtained under constant riverbed erosion rate and assuming additive gaussian process noise. By this mean, we explore the level of determinism and stochasticity affecting the time-to-uprooting for Avena sativa in relation to root anchoring and flow drag forces. We eventually ascribe the overall dynamics of the Type II uprooting mechanism to the memory of the plant-soil system that is stored by root anchoring, and discuss related implications thereof. References Edmaier, K., Uprooting mechansims of juvenile vegetation by flow erosion, Ph.D. thesis, EPFL, 2014. Edmaier, K., Crouzy, B. and P. Perona. Experimental characterization of vegetation uprooting by flow. J. of Geophys. Res. - Biogeosci., submitted

  18. Multi-phase Flow Modeling applied to Metallurgical Processes

    Directory of Open Access Journals (Sweden)

    Stein T. Johansen

    2002-04-01

    Full Text Available Multiphase flow models have been improved significantly during the last two decades. Together with the development of more advanced numerical techniques and faster and cheaper computers we now see that computational fluid dynamics (CFD becomes a powerful tool in predicting the performance of complex industrial processes. In particular the processes faced by the metallurgical industries may serve as examples of such complexity.

  19. Coaching, lean processes and the concept of flow

    DEFF Research Database (Denmark)

    Skytte Gørtz, Kim Erik

    2008-01-01

    The chapter takes us inside Nordea Bank to look at how coaching was used to support their leadership development as they underwent a major change effort implementation. Drawing on the literature on Lean processes, flow and coaching, it demonstrates some of the challenges and opportunities of working with coaching in a systematic way across broader initiatives in organizations.

  20. 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

  1. 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.

  2. 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.

  3. 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

  4. 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.

  5. 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.

  6. 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 basic for design of control strategies and for the allocation of control tasks to the computer and the plant operator. (author)

  7. 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.

  8. 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.

  9. 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.

  10. Coded ultrasound for blood flow estimation using subband processing

    DEFF Research Database (Denmark)

    Gran, F.; Udesen, J.; Jensen, J.A.; Nielsen, Michael Bachmann

    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 ...

  11. Coded ultrasound for blood flow estimation using subband processing

    DEFF Research Database (Denmark)

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

    2007-01-01

    This paper further 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 sub-band processing. The received broadband signal, is filtered using a set of narrow-band filters. Estimating the velocity in each of the bands and aver...

  12. Coded Ultrasound for Blood Flow Estimation Using Subband Processing

    DEFF Research Database (Denmark)

    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 the ...

  13. Production process flow optimization at Euro-Plastifoam (Pty) Ltd

    OpenAIRE

    Zietsman, Ignatius

    2011-01-01

    Various methods, tools and techniques will be applied in order to improve, and ultimately optimize, the production process flow at Euro-Plastifoam. Work measurement will be performed, followed by value stream analysis as well as the application of problem identification methods. This again, will be followed by layout analysis and improvement. Other proposed solutions include the introduction of a Kanban system, 5S House keeping and Single Minute Exchange of Dies (SMED).

  14. The process flow and structure of an integrated stroke strategy

    OpenAIRE

    Emma F. van Bussel; Thomas Jeerakathil; Schrijvers, Augustinus J.P

    2013-01-01

    Introduction: In the Canadian province of Alberta access and quality of stroke care were suboptimal, especially in remote areas. The government introduced the Alberta Provincial Stroke Strategy (APSS) in 2005, an integrated strategy to improve access to stroke care, quality and efficiency which utilizes telehealth. Research question: What is the process flow and the structure of the care pathways of the APSS?Methodology: Information for this article was obtained using documentation, archival ...

  15. Modelling of macropore flow and transport processes at catchment scale

    Science.gov (United States)

    Skovdal Christiansen, Jesper; Thorsen, Mette; Clausen, Thomas; Hansen, Søren; Christian Refsgaard, Jens

    2004-11-01

    Macropores play a significant role as a preferential flow mechanism in connection with pesticide leaching to shallow groundwater in clayey and loamy soils. A macropore description based on some of the same principles as those of the MACRO code has been added to the coupled MIKE SHE/Daisy code, enabling a physically based simulation of macropore processes in a spatially distributed manner throughout an entire catchment. Simulation results from a small catchment in Denmark suggest that although the point scale macropore processes have no dominating effect on groundwater recharge or discharge at a catchment scale, they will have significant effects on pesticide leaching to groundwater at a catchment scale. The primary function of macropores in this area is that they rapidly transport a significant part of the infiltrating water and solutes from the plough pan at 20 cm depth some distance downwards before most of it flows back into the soil matrix. This has a very significant effect on the leaching of pesticides from the surface to the groundwater table, because some of the pesticides are transported rapidly downwards in the soil profile to zones with less sorption and degradation. It is concluded that the spatial variations of macropore flows caused by the variation in topography and depth to groundwater table within a catchment are so large that this has to be accounted for in up-scaling process descriptions and results from point scale to catchment scale.

  16. Electrochemical analysis on the process of flow accelerated corrosion

    International Nuclear Information System (INIS)

    Flow accelerated corrosion behavior concerning both activation and mass transfer process of low alloy steel was studied using rotating cyclinder electrode in room temperature alkaline solution by electrochemical techniques. Passive film was formed pH 9.8 by step oxidation of ferrous product into hydroxyl compound. Corrosion potential shifted slightly upward with rotating velocity through the diffusion of cathodic species. From the analysis between corrosion current and limiting current, there seems that activation process, which represents formation of passive film on the bare metal surface, controls the entire corrosion kinetics

  17. 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.

  18. Nonlinear compressible magnetohydrodynamic flows modeling of a process ICP torch

    Science.gov (United States)

    Ikhlef, N.; Hacib, T.; Leroy, O.; Mékiddèche, M. R.

    2012-04-01

    Magnetohydrodynamics (MHD) describes the physical behavior of inductively coupled plasma (ICP). The goal of this paper is to provide a physical understanding of a process ICP torch using a resistive MHD model. This includes a basic description and derivation of the fluid model. Inductive plasma is treated as a continuous, conducting fluid that satisfies the classical laws of motion and thermodynamics. This model combines fluid equations, similar to those used in fluid dynamics, with Maxwell's equations. Steady fluid flow and temperature equations are simultaneously solved (direct method) using a finite elements method (FEM). The electromagnetic field equations are formulated in terms of potential vector with applied voltage source, so this model is physically more consistent, a more accurate and a faster simulation. The governing resistive MHD equations for an inductive plasma flow under local thermodynamic equilibrium (LTE) and laminar flow are presented, with appropriate boundary conditions. The model enabled to obtain the electromagnetic fields, temperature and flow velocity distributions also allows the determination of the electric parameters such as impedance of the plasma torch, total power, eddy losses, etc.

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

    Energy Technology Data Exchange (ETDEWEB)

    Lisnyi, Bohdan, E-mail: lisnyj@icmp.lviv.ua [Department of Theoretical Physics and Astrophysics, Faculty of Science, P.J. Šafárik University, Park Angelinum 9, 040 01 Košice (Slovakia); Institute for Condensed Matter Physics, National Academy of Sciences of Ukraine, 1 Svientsitskii Street, 79011 L' viv (Ukraine); Stre?ka, Jozef, E-mail: jozef.strecka@upjs.sk [Department of Theoretical Physics and Astrophysics, Faculty of Science, P.J. Šafárik University, Park Angelinum 9, 040 01 Košice (Slovakia)

    2013-11-15

    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.

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

    OpenAIRE

    Cavazzini, Giovanna; DAZIN, Antoine; Pavesi, Giorgio; DUPONT, Patrick; Bois, Gérard

    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...

  1. Flow processes at low temperatures in ultrafine-grained aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Chinh, Nguyen Q. [Department of General Physics, Eoetvoes University of Budapest, 1117 Budapest, Pazmany P. setany 1/A. (Hungary)]. E-mail: chinh@metal.elte.hu; Szommer, Peter [Department of General Physics, Eoetvoes University of Budapest, 1117 Budapest, Pazmany P. setany 1/A. (Hungary); Csanadi, Tamas [Department of General Physics, Eoetvoes University of Budapest, 1117 Budapest, Pazmany P. setany 1/A. (Hungary); Langdon, Terence G. [Departments of Aerospace and Mechanical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089-1453 (United States); Materials Research Group, School of Engineering Sciences, University of Southampton, Southampton SO17 1BJ (United Kingdom)

    2006-10-25

    Experiments were conducted to evaluate the flow behavior of pure aluminum at low temperatures. Samples were processed by equal-channel angular pressing (ECAP) to give a grain size of {approx}1.2 {mu}m and compression samples were cut from the as-pressed billets and tested over a range of strain rates at temperatures up to 473 K. The results show the occurrence of steady-state flow in these highly deformed samples and a detailed analysis gives a low strain rate sensitivity and an activation energy similar to the value for grain boundary diffusion. By using depth-sensing indentation testing and atomic force microscopy, it is shown that grain boundary sliding occurs in this material at low temperatures. This result is attributed to the presence of high-energy non-equilibrium boundaries in the severely deformed samples.

  2. Flow processes at low temperatures in ultrafine-grained aluminum

    International Nuclear Information System (INIS)

    Experiments were conducted to evaluate the flow behavior of pure aluminum at low temperatures. Samples were processed by equal-channel angular pressing (ECAP) to give a grain size of ?1.2 ?m and compression samples were cut from the as-pressed billets and tested over a range of strain rates at temperatures up to 473 K. The results show the occurrence of steady-state flow in these highly deformed samples and a detailed analysis gives a low strain rate sensitivity and an activation energy similar to the value for grain boundary diffusion. By using depth-sensing indentation testing and atomic force microscopy, it is shown that grain boundary sliding occurs in this material at low temperatures. This result is attributed to the presence of high-energy non-equilibrium boundaries in the severely deformed samples

  3. 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

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

    Science.gov (United States)

    Kulcu, Recep; Yaldiz, Osman

    2008-01-01

    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, CO(2) and O(2) 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. PMID:17888646

  5. RANS-based simulation of turbulent wave boundary layer and sheet-flow sediment transport processes

    DEFF Research Database (Denmark)

    Fuhrman, David R.; SchlØer, Signe

    2013-01-01

    A numerical model coupling the horizontal component of the incompressible Reynolds-averaged Navier–Stokes (RANS) equationswith two-equation k?? turbulence closure is presented and used to simulate a variety of turbulent wave boundary layer processes. The hydrodynamic model is additionally coupled with bed and suspended load descriptions, the latter based on an unsteady turbulent-diffusion equation, for simulation of sheet-flow sediment transport processes. In addition to standard features common within such RANS-based approaches, the present model includes: (1) hindered settling velocities at high suspended sediment concentrations, (2) turbulence suppression due to density gradients in the water–sand mixture, (3) boundary layer streaming due to convective terms, and (4) converging–diverging effects due to a sloping bed. The present model therefore provides a framework for simultaneous inclusion of a number of local factors important within cross-shore wave boundary layer and sediment transport dynamics. The hydrodynamic model is validated for both hydraulically smooth and rough conditions, based on wave friction factor diagrams and boundary layer streaming profiles, with the results in excellent agreement with experimental and/or previous numerical work. The sediment transport model is likewise validated against oscillatory tunnel experiments involving both velocity-skewed and acceleration-skewed flows, as well as against measurements beneath real progressive waves.Model capabilities are exploited to investigate the importance of boundary layer streaming effects on sediment transport in selected velocity-skewed conditions. For the medium sand grain conditions considered, the model results suggest that streaming effects can enhance onshore sediment transport rates by asmuch as a factor of two.Moreover, for fine sand conditions streaming (and related convective) effects are demonstrated to potentially reverse the direction of net transport (i.e. from offshore to onshore) relative that predicted in oscillatory tunnel conditions. The developed model is implemented within the popular Matlab environment, and hence may be attractive for both research and educational purposes.

  6. Diagramming Complex Activities

    DEFF Research Database (Denmark)

    Andersen, Peter BØgh

    2005-01-01

    We increasingly live in heterogeneous ever-changing webs of activities where human actions are intertwined with events created by automatic machines.  In order to make such webs understandable to its human participants, their structure should be represented by displays emphasizing their action aspect. The paper suggests thematic roles as a semantics for actions, argues that a selection of well-known diagramming techniques can be defined within this theory, and uses the theory to discuss new issues related to process control and mobile technology.

  7. Do health technology assessments comply with QUOROM diagram guidance? An empirical study

    Directory of Open Access Journals (Sweden)

    Booth Andrew

    2007-11-01

    Full Text Available Abstract Background The Quality of Reporting of Meta-analyses (QUOROM statement provides guidance for improving the quality of reporting of systematic reviews and meta-analyses. To make the process of study selection transparent it recommends "a flow diagram providing information about the number of RCTs identified, included, and excluded and the reasons for excluding them". We undertook an empirical study to identify the extent of compliance in the UK Health Technology Assessment (HTA programme. Methods We searched Medline to retrieve all systematic reviews of therapeutic interventions in the HTA monograph series published from 2001 to 2005. Two researchers recorded whether each study contained a meta-analysis of controlled trials, whether a QUOROM flow diagram was presented and, if so, whether it expressed the relationship between the number of citations and the number of studies. We used Cohen's kappa to test inter-rater reliability. Results 87 systematic reviews were retrieved. There was good and excellent inter-rater reliability for, respectively, whether a review contained a meta-analysis and whether each diagram contained a citation-to-study relationship. 49% of systematic reviews used a study selection flow diagram. When only systematic reviews containing a meta-analysis were analysed, compliance was only 32%. Only 20 studies (23% of all systematic reviews; 43% of those having a study selection diagram had a diagram which expressed the relationship between citations and studies. Conclusion Compliance with the recommendations of the QUOROM statement is not universal in systematic reviews or meta-analyses. Flow diagrams make the conduct of study selection transparent only if the relationship between citations and studies is clearly expressed. Reviewers should understand what they are counting: citations, papers, studies and trials are fundamentally different concepts which should not be confused in a diagram.

  8. Analysis of Nike distribution facility's outbound process flow

    OpenAIRE

    Wagenaar, Werner

    2009-01-01

    A simulation study was conducted to run different scenarios on the outbound process flow affected by the Soccer World Cup 2010 event. Along with Excel spreadsheets this simulation proved to be vital in the decision making of the build up for the World Cup. The results obtained showed that not all KPI’s where at their optimal level, thus changes where made in the number of resource at certain workstations. It also indicated that the system was resistant to change and modifications on proces...

  9. Groundwater flow and sorption processes in fractured rocks (I)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Won Young; Woo, Nam Chul; Yum, Byoung Woo; Choi, Young Sub; Chae, Byoung Kon; Kim, Jung Yul; Kim, Yoo Sung; Hyun, Hye Ja; Lee, Kil Yong; Lee, Seung Gu; Youn, Youn Yul; Choon, Sang Ki [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1996-12-01

    This study is objected to characterize groundwater flow and sorption processes of the contaminants (ground-water solutes) along the fractured crystalline rocks in Korea. Considering that crystalline rock mass is an essential condition for using underground space cannot be overemphasized the significance of the characterizing fractured crystalline rocks. the behavior of the groundwater contaminants is studied in related to the subsurface structure, and eventually a quantitative technique will be developed to evaluate the impacts of the contaminants on the subsurface environments. The study has been carried at the Samkwang mine area in the Chung-Nam Province. The site has Pre-Cambrian crystalline gneiss as a bedrock and the groundwater flow system through the bedrock fractures seemed to be understandable with the study on the subsurface geologic structure through the mining tunnels. Borehole tests included core logging, televiewer logging, constant pressure fixed interval length tests and tracer tests. The results is summarized as follows; 1) To determine the hydraulic parameters of the fractured rock, the transient flow analysis produce better results than the steady - state flow analysis. 2) Based on the relationship between fracture distribution and transmissivities measured, the shallow part of the system could be considered as a porous and continuous medium due to the well developed fractures and weathering. However, the deeper part shows flow characteristics of the fracture dominant system, satisfying the assumptions of the Cubic law. 3) Transmissivities from the FIL test were averaged to be 6.12 x 10{sup -7}{sub m}{sup 2}{sub /s}. 4) Tracer tests result indicates groundwater flow in the study area is controlled by the connection, extension and geometry of fractures in the bedrock. 5) Hydraulic conductivity of the tracer-test interval was in maximum of 7.2 x 10{sup -6}{sub m/sec}, and the effective porosity of 1.8 %. 6) Composition of the groundwater varies with that of contacting geomedia and the significant change occurs in K and Fe. 7) Metal ions in groundwater were found to be sorbed onto groundwater particulates. (author). 128 refs., 39 tabs., 49 figs.

  10. Which factors, processes and storages influence low flow (Q347)?

    Science.gov (United States)

    Margreth, Michael; Scherrer, Simon; Smoorenburg, Maarten; Naef, Felix

    2013-04-01

    In Switzerland, estimation of residual water is based on Q347 (flow exceeded during 347 days per year). In ungauged catchments Q347 has to be determined with some simplified approaches. However, these statistical models often provide inaccurate results. The runoff reaction of a river depends on the spatial distribution of the Dominant Runoff Processes (DRP) like Hortonian Overland Flow (HOF), Saturated Overland Flow (SOF), Sub-Surface Flow (SSF) or Deep Percolation (DP) within its catchment area. Low flow is fed by slowly reacting groundwater or deep hillslope storages. These storages are supposed to be located mainly beneath permeable soils in highly permeable bedrock like talus, deposits of debris flows or rock fall, gravel of river deposits, lateral moraines or karst systems, represented in DRP-maps by slowly reacting SOF3-, SSF3- or DP- areas. To better understand these mechanisms, the relation between areas of slowly reacting SOF3, SSF3, DP and the form of the recession curves was analysed in 27 catchments of Swiss Plateau and Jura. Results show, that drainage characteristics and percentage of SOF3-, SSF3- and DP- areas in catchments relate well. The more extended the recharge areas, the smoother and longer the recession curves. For example the recession to Q347 in the Eulach River (Area of SOF3, SSF3, DP = 54%) takes 95 days, in the Töss River only 10 days (Area of SOF3, SSF3, DP = 9%). However, the differences in Q347 cannot be explained with these percentages. The runoff volume from Q347 to Q365 in 14 investigated catchments is only between 0.2 and 14 mm, about 1.5% of the annual precipitation volume. It seems that the storages mentioned above do not contribute significantly any more, when the discharge falls below Q347. It was found that catchments with high Q347 consist mainly of sandstone, conglomerate or large scaled wetlands. It seems that mainly porous and fissured solid rocks contribute to Q347. Very small Q347 are usually caused by seepage loss of water in the riverbed.

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

    International Nuclear Information System (INIS)

    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 156605]. 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

  12. 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.

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

    International Nuclear Information System (INIS)

    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

  14. The process flow and structure of an integrated stroke strategy

    Directory of Open Access Journals (Sweden)

    Emma F. van Bussel

    2013-06-01

    Full Text Available Introduction: In the Canadian province of Alberta access and quality of stroke care were suboptimal, especially in remote areas. The government introduced the Alberta Provincial Stroke Strategy (APSS in 2005, an integrated strategy to improve access to stroke care, quality and efficiency which utilizes telehealth. Research question: What is the process flow and the structure of the care pathways of the APSS?Methodology: Information for this article was obtained using documentation, archival APSS records, interviews with experts, direct observation and participant observation.Results: The process flow is described. The APSS integrated evidence-based practice, multidisciplinary communication, and telestroke services. It includes regular quality evaluation and improvement.Conclusion: Access, efficiency and quality of care improved since the start of the APSS across many domains, through improvement of expertise and equipment in small hospitals, accessible consultation of stroke specialists using telestroke, enhancing preventive care, enhancing multidisciplinary collaboration, introducing uniform best practice protocols and bypass-protocols for the emergency medical services.Discussion: The APSS overcame substantial obstacles to decrease discrepancies and to deliver integrated higher quality care. Telestroke has proven itself to be safe and feasible. The APSS works efficiently, which is in line to other projects worldwide, and is, based on limited results, cost effective. Further research on cost-effectiveness is necessary.

  15. 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.

  16. 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.

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

    International Nuclear Information System (INIS)

    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)

  18. 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).

  19. Semantics of UML 2.0 Activity Diagram for Business Modeling by Means of Virtual Machine

    CERN Document Server

    Vitolins, V; Vitolins, Valdis; Kalnins, Audris

    2005-01-01

    The paper proposes a more formalized definition of UML 2.0 Activity Diagram semantics. A subset of activity diagram constructs relevant for business process modeling is considered. The semantics definition is based on the original token flow methodology, but a more constructive approach is used. The Activity Diagram Virtual machine is defined by means of a metamodel, with operations defined by a mix of pseudocode and OCL pre- and postconditions. A formal procedure is described which builds the virtual machine for any activity diagram. The relatively complicated original token movement rules in control nodes and edges are combined into paths from an action to action. A new approach is the use of different (push and pull) engines, which move tokens along the paths. Pull engines are used for paths containing join nodes, where the movement of several tokens must be coordinated. The proposed virtual machine approach makes the activity semantics definition more transparent where the token movement can be easily tra...

  20. 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

  1. 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).

  2. 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).

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

    International Nuclear Information System (INIS)

    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)

  4. Manufacturing process planning optimisation in reconfigurable multiple parts flow lines

    Directory of Open Access Journals (Sweden)

    N. Ismail

    2008-12-01

    Full Text Available Purpose: This paper explores the capabilities of genetic algorithms in handling optimization of the criticalissues mentioned above for the purpose of manufacturing process planning in reconfigurable manufacturingactivities. Two modified genetic algorithms are devised and employed to provide the best approximate processplanning solution. Modifications included adapting genetic operators to the problem specific knowledge andimplementing application specific heuristics to enhance the search efficiency.Design/methodology/approach: The genetic algorithm methodology implements a genetic algorithmthat is augmented by application specific heuristics in order to guide the search for an optimal solution.The case study is based on the manufacturing system. Raw materials enter the system through an input stageand exit the system through an output stage. The system is composed of sixteen (16 processing modulesthat are arranged in four processing stages.Findings: The results indicate that the two genetic algorithms are able to converge to optimal solutionsin reasonable time. A computational study shows that improved solutions can be obtained by implementinga genetic algorithm with an extended diversity control mechanism.Research limitations/implications: This paper has examined the issues of MPP optimization in a reconfigurablemanufacturing framework with the help of a reconfigurable multiparts manufacturing flow line.Originality/value: The results of the case illustration have demonstrated the practical use of diversity controlimplemented in the MGATO technique. In comparison to MGAWTO, the implemented MGATO improves thepopulation diversity through a customized threshold operator. It was clear that the MGATO can obtain bettersolution quality by foiling the tendency towards premature convergence.

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

    Energy Technology Data Exchange (ETDEWEB)

    Yorstos, Yannis C.

    2003-03-19

    The report describes progress made in the various thrust areas of the project, which include internal drives for oil recovery, vapor-liquid flows, combustion and reaction processes and the flow of fluids with yield stress.

  6. 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 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)

  7. Braided chord diagrams

    CERN Document Server

    Birman, J S; Birman, Joan S.; Trapp, Rolland

    1998-01-01

    The notion of a braided chord diagram is introduced and studied. An equivalence relation is given which identifies all braidings of a fixed chord diagram. It is shown that finite-type invariants are stratified by braid index for knots which can be represented as closed 3-braids. Partial results are obtained about spanning sets for the algebra of chord diagrams of braid index 3.

  8. 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.

  9. Hertzsprung-Russell Diagram

    Science.gov (United States)

    Chiosi, C.; Murdin, P.

    2000-11-01

    The Hertzsprung-Russell diagram (HR-diagram), pioneered independently by EJNAR HERTZSPRUNG and HENRY NORRIS RUSSELL, is a plot of the star luminosity versus the surface temperature. It stems from the basic relation for an object emitting thermal radiation as a black body: ...

  10. 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

  11. 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

  12. The Classroom as Rhizome: New Strategies for Diagramming Knotted Interactions

    Science.gov (United States)

    de Freitas, Elizabeth

    2012-01-01

    This article calls attention to the unexamined role of diagrams in educational research and offers examples of alternative diagramming practices or tools that shed light on classroom interaction as a rhizomatic process. Drawing extensively on the work of Latour, Deleuze and Guattari, and Chatelet, this article explores the power of diagramming as…

  13. Using Affinity Diagrams to Evaluate Interactive Prototypes

    DEFF Research Database (Denmark)

    Lucero, Andrés

    2015-01-01

    Affinity diagramming is a technique used to externalize, make sense of, and organize large amounts of unstructured, far-ranging, and seemingly dissimilar qualitative data. HCI and interaction design practitioners have adopted and used affinity diagrams for different purposes. This paper discusses our particular use of affinity diagramming in prototype evaluations. We reflect on a decade’s experience using affinity diagramming across a number of projects, both in industry and academia. Our affinity diagramming process in interaction design has been tailored and consists of four stages: creating notes, clustering notes, walking the wall, and documentation. We draw examples from eight projects to illustrate our particular practices along these four stages, as well as to ground the discussion.

  14. Work flow of signal processing data of ground penetrating radar case of rigid pavement measurements

    International Nuclear Information System (INIS)

    The signal processing of Ground Penetrating Radar (GPR) requires a certain work flow to obtain good results. Even though the Ground Penetrating Radar data looks similar with seismic reflection data, but the GPR data has particular signatures that the seismic reflection data does not have. This is something to do with coupling between antennae and the ground surface. Because of this, the GPR data should be treated differently from the seismic signal data processing work flow. Even though most of the processing steps still follow the same work flow of seismic reflection data such as: filtering, predictive deconvolution etc. This paper presents the work flow of GPR processing data on rigid pavement measurements. The processing steps start from raw data, de-Wow process, remove DC and continue with the standard process to get rid of noises i.e. filtering process. Some radargram particular features of rigid pavement along with pile foundations are presented

  15. Work flow of signal processing data of ground penetrating radar case of rigid pavement measurements

    Energy Technology Data Exchange (ETDEWEB)

    Handayani, Gunawan [The Earth Physics and Complex Systems Research Group (Jl. Ganesa 10 Bandung Indonesia) gunawanhandayani@gmail.com (Indonesia)

    2015-04-16

    The signal processing of Ground Penetrating Radar (GPR) requires a certain work flow to obtain good results. Even though the Ground Penetrating Radar data looks similar with seismic reflection data, but the GPR data has particular signatures that the seismic reflection data does not have. This is something to do with coupling between antennae and the ground surface. Because of this, the GPR data should be treated differently from the seismic signal data processing work flow. Even though most of the processing steps still follow the same work flow of seismic reflection data such as: filtering, predictive deconvolution etc. This paper presents the work flow of GPR processing data on rigid pavement measurements. The processing steps start from raw data, de-Wow process, remove DC and continue with the standard process to get rid of noises i.e. filtering process. Some radargram particular features of rigid pavement along with pile foundations are presented.

  16. Modeling and analysis of coupled porous-medium and free flow with application to evaporation processes

    OpenAIRE

    Mosthaf, Klaus

    2014-01-01

    Exchange processes between fluid-filled porous media and an adjacent free flow occur in a wide range of natural and technical systems. In the course of these processes, the flow dynamics in the porous domain and in the free flow exhibit a strong interdependency, which is often controlled by mechanisms at the common interface. Understanding and modeling these interactions is decisive for divers technical, medical and environmental applications. Prominent technical examples are the drying of pr...

  17. Real-time blood flow visualization using the graphics processing unit

    OpenAIRE

    Yang, Owen; Cuccia, David; Choi, Bernard

    2011-01-01

    Laser speckle imaging (LSI) is a technique in which coherent light incident on a surface produces a reflected speckle pattern that is related to the underlying movement of optical scatterers, such as red blood cells, indicating blood flow. Image-processing algorithms can be applied to produce speckle flow index (SFI) maps of relative blood flow. We present a novel algorithm that employs the NVIDIA Compute Unified Device Architecture (CUDA) platform to perform laser speckle image processing on...

  18. Experimental study of air flow rate effects on humidification parameters with preheating and dehumidification process changing

    OpenAIRE

    Ayad T. Mustafa

    2011-01-01

    The objective of this research is to study experimentally the effect of air flow rate on humidification process parameters. Experimental data are obtained from air conditioning study unit T110D. Results obtained from experimental test, calculations and psychometrics software are discussed. The effect of air flow rate on steam humidification process parameters as a part of air-conditioning processes can be explain in results obtained. Results of the steam humidification process with and withou...

  19. Mixing and Demixing Processes in Multiphase Flows With Application to Propulsion Systems

    Science.gov (United States)

    Decker, Rand (editor); Schafer, Charles F. (editor)

    1988-01-01

    A workshop on transport processes in multiphase flow was held at the Marshall Space Flight Center on February 25 and 26, 1988. The program, abstracts and text of the presentations at this workshop are presented. The objective of the workshop was to enhance our understanding of mass, momentum, and energy transport processes in laminar and turbulent multiphase shear flows in combustion and propulsion environments.

  20. Conceptual process flow of a fluoride volatility process under 'milder' condition

    International Nuclear Information System (INIS)

    A new conceptual process flow for reprocessing by fluoride volatility process is constructed that could be operated economically under a 'milder' condition compared to the conventional process. The two-step fluorination method using mixed gas of HF and H2, and F2 is employed to reduce the reaction temperature and F2 concentration in this process. PuF3 and UF4 formed at the 1st stage would be fluorinated to gaseous hexafluorides simultaneously, on the other hand, involatile fluorides would remain in the reactor. Most of the volatilised UF6, PuF6 and other substances would be condensed in the cold trap. UF6 could be purified by removing other substances with chemical traps after volatilising them at the specific temperature and pressure. The mixed UF6 and PuF6 that remain in the cold trap would be volatilised together to be used as the raw material of MOX fuel after adjusting the plutonium enrichment ratio. (author)

  1. Identification of the molten glass flow process in tank furnaces

    International Nuclear Information System (INIS)

    A mathematical model for the evaluation of flow dynamics of molten glass within a tank furnace has been developed. The technological and dynamical parameters were obtained for an industrial and a model tank furnace using 140La as a tracer. The results are in good agreement with theoretical values computed on the basis of a complex flow model (Wolf-Resnick model) with the aid of the MARMOD code

  2. 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

  3. 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.

  4. 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

  5. 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

  6. Multiphase flow modeling: A tool to aid in scale up of processes

    Science.gov (United States)

    Nandakumar, Krishnaswamy

    2010-10-01

    Multiphase flows are ubiquitous in chemical processing industries. Traditional approach has been to ignore fluid dynamical effects by invoking simplifying assumptions of homogeneity, but pay the price during scale-up of processes. The question that I address is ``Can Multiphase flow modeling come to our rescue in minimizing the need for pilot scale experiments?'' On the fundamental side, we have developed algorithms for direct numerical simulation of multiphase flows. For dispersed rigid particles as in suspension flows, sedimentation etc, we couple the Navier-Stokes equations with the rigid body dynamics in a rigorous fashion to track the particle motion in a fluid. For deformable bubbles/droplets dispersed in another fluid, we also track their motion in an Eulerian grid. The two classes of algorithms show great promise in attempting direct simulation of multiphase flows, from which we can extract statistically meaningful average behavior of suspensions or bubbly flows. On the other hand, there is an immediate need to study flow of complex fluids of industrial importance. Such cases include polymer blending processes, erosion in pipelines and process vessels and mass transfer in packed beds. In such studies we use volume averaged equations as the basis of flow models coupled with experimental validation of such predictions in an effort to develop scale invariant closure models that are needed as part of the volume averaged flow models.

  7. Finding and Accessing Diagrams in Biomedical Publications

    OpenAIRE

    Kuhn, Tobias; Luong, Thaibinh; Krauthammer, Michael

    2012-01-01

    Complex relationships in biomedical publications are often communicated by diagrams such as bar and line charts, which are a very effective way of summarizing and communicating multi-faceted data sets. Given the ever-increasing amount of published data, we argue that the precise retrieval of such diagrams is of great value for answering specific and otherwise hard-to-meet information needs. To this end, we demonstrate the use of advanced image processing and classification for identifying bar...

  8. Traffic dynamics: Its impact on the Macroscopic Fundamental Diagram

    Science.gov (United States)

    Knoop, Victor L.; van Lint, Hans; Hoogendoorn, Serge P.

    2015-11-01

    Literature shows that-under specific conditions-the Macroscopic Fundamental Diagram (MFD) describes a crisp relationship between the average flow (production) and the average density in an entire network. The limiting condition is that traffic conditions must be homogeneous over the whole network. Recent works describe hysteresis effects: systematic deviations from the MFD as a result of loading and unloading. This article proposes a two dimensional generalization of the MFD, the so-called Generalized Macroscopic Fundamental Diagram (GMFD), which relates the average flow to both the average density and the (spatial) inhomogeneity of density. The most important contribution is that we show this is a continuous function, of which the MFD is a projection. Using the GMFD, we can describe the mentioned hysteresis patterns in the MFD. The underlying traffic phenomenon explaining the two dimensional surface described by the GMFD is that congestion concentrates (and subsequently spreads out) around the bottlenecks that oversaturate first. We call this the nucleation effect. Due to this effect, the network flow is not constant for a fixed number of vehicles as predicted by the MFD, but decreases due to local queueing and spill back processes around the congestion "nuclei". During this build up of congestion, the production hence decreases, which gives the hysteresis effects.

  9. Diagrams of States in Quantum Information: an Illustrative Tutorial

    CERN Document Server

    Felloni, Sara; Strini, Giuliano

    2009-01-01

    We present "Diagrams of States", a way to graphically represent and analyze how quantum information is elaborated during the execution of quantum circuits. This introductory tutorial illustrates the basics, providing useful examples of quantum computations: elementary operations in single-qubit, two-qubit and three-qubit systems, immersions of gates on higher dimensional spaces, generation of single and multi-qubit states, procedures to synthesize unitary, controlled and diagonal matrices. To perform the analysis of quantum processes, we directly derive diagrams of states from physical implementations of quantum circuits associated to the processes. Complete diagrams are then rearranged into simplified diagrams, to visualize the overall effects of computations. Conversely, diagrams of states help to conceive new quantum algorithms, by schematically describing desired manipulations of quantum information with intuitive diagrams and then by guessing the equivalent complete diagrams, from which the corresponding...

  10. Aerodynamic structures and processes in rotationally augmented flow fields

    DEFF Research Database (Denmark)

    Schreck, S.J.; SØrensen, Niels N.

    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 above-surface flow field structure and used to deduce mechanisms; underlying augmented aerodynamic force production during rotating conditions. Copyright (C) 2007 John Wiley & Sons, Ltd.

  11. 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.

  12. A viscous flow analysis of the tip vortex generation process

    Science.gov (United States)

    Shamroth, S. J.; Briley, W. R.

    1979-01-01

    A viscous primary-secondary flow analysis designed for numerical solution by forward marching integration is applied to the tip vortex generation problem. Equations governing streamwise momentum, streamwise vorticity, and a gas law are solved in conjunction with equations governing scalar and vector surface potentials for the secondary velocities. The numerical method used combines a consistently split linearized block implicit (LBI) scheme for parabolic equations and a scalar iterative ADI scheme for elliptic equations. Computed results are presented for a wing of rectangular planform immersed in a high Reynolds number stream at 6 degrees incidence. The physical mechanism for generation of the tip vortex, as revealed by the analysis and computations, is discussed. Detailed flow results for the case of 6 degree incidence are included.

  13. Flow-Injection Responses of Diffusion Processes and Chemical Reactions

    DEFF Research Database (Denmark)

    Andersen, Jens Enevold Thaulov

    2000-01-01

    The technique of Flow-injection Analysis (FIA), now aged 25 years, offers unique analytical methods that are fast, reliable and consuming an absolute minimum of chemicals. These advantages together with its inherent feasibility for automation warrant the future applications of FIA as an attractive tool of automated analytical chemistry. The need for an even lower consumption of chemicals and for computer analysis has motivated a study of the FIA peak itself, that is, a theoretical model was deve...

  14. Model-based decentralised automatic management of product flow paths in processing plants

    OpenAIRE

    Quirós Araya, Gustavo Arturo

    2010-01-01

    This work introduces the model of product flow paths as a formal framework for the correct execution of product flow operations in processing plants. A product flow path is a software object responsible for controlling, monitoring and documenting the movement of products along a determined route in the plant, and represents a temporarily and spatially isolated area for the safe and correct transport of products. A formal model provides a guide for the implementation of decentralised object-or...

  15. 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...)

  16. 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...

  17. 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.

  18. 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.

  19. Studies on statics of 1 exstraction of Purex process. Low-acid flow sheet

    International Nuclear Information System (INIS)

    A steady-state of 16-stage countercurrent extraction process has been studied for the system UO2(NO3)2 - Pu(NO3)4 - HNO3/30% TBP. Three various methods were used for the determination of concentration profiles: experimental, graphical (diagrams X-Y of McCabe-Thiele type) and analytical (an adapted form of Groenier's computer program SEPHIS). Using the computer method, a circulation and accumulation of plutonium was studied as a function of solvent loading with uranium and plutonium and of the feed solution acidity. (author)

  20. Generalized Fleming-Viot processes with immigration via stochastic flows of partitions

    CERN Document Server

    Foucart, Clément

    2011-01-01

    The generalized Fleming-Viot processes were defined in 1999 by Donnelly and Kurtz using a particle model and by Bertoin and Le Gall in 2003 using stochastic flows of bridges. In both methods, the key argument used to characterize these processes is the duality between these processes and exchangeable coalescents. A larger class of coalescent processes, called distinguished coalescents, was set up recently to incorporate an immigration phenomenon in the underlying population. The purpose of this article is to define and characterize a class of probability-measure valued processes called the generalized Fleming-Viot processes with immigration. We consider some stochastic flows of partitions of Z_{+}, in the same spirit as Bertoin and Le Gall's flows, replacing roughly speaking, composition of bridges by coagulation of partitions. Identifying at any time a population with the integers $\\mathbb{N}:=\\{1,2,...\\}$, the formalism of partitions is effective in the past as well as in the future especially when there ar...

  1. Predicting the Effects of Common Levels of Variability on Flow Processing Systems

    OpenAIRE

    David STOCKTON; Khalil, Riham; Fresco, John Anthony

    2008-01-01

    Abstract The implementation of flow processing is essential to the successful application of lean manufacturing practices since it provides the infrastructure for both pull production to take place and the focussed elimination of waste. With the adoption of lean practices into a broader range of production environments there is an increasing need for flow processing to operate under a wider range of conditions particularly with respect to the sources and levels of variability that ...

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

    Energy Technology Data Exchange (ETDEWEB)

    Yortsos, Yanis C.

    2002-10-08

    In this report, the thrust areas 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.

  3. Space Based Multi-level Process Flow and Logistics Analysis

    OpenAIRE

    Zhou Qiu-Zhong; Ning Guo-Liang; Xu Wan-Hong

    2013-01-01

    In order to thoroughly promote the enterprise digital construction and meet the demand of production management, the space based multi-level process data organization model has been put forward. Firstly, according to the practical division situation of enterprise production space, the multi-level organization method of production space has been proposed. Then through analyzing the manufacturing process of the products in different space layers, the space based mu...

  4. Prediction of hygiene in food processing equipment using flow modelling

    DEFF Research Database (Denmark)

    Friis, Alan; Jensen, Bo Boye Busk

    2002-01-01

    Computational fluid dynamics (CFD) has been applied to investigate the design of closed process equipment with respect to cleanability. The CFD simulations were validated using the standardized cleaning test proposed by the European Hygienic Engineering and Design Group. CFD has been proven as a tool which can be used by manufacturers to facilitate their equipment design for high hygienic standards before constructing any prototypes. The study of hydrodynamic cleanability of closed processing eq...

  5. 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.

  6. Total Quality Management (TQM): Training Module on "Focus on Processes."

    Science.gov (United States)

    Leigh, David

    This module for a 1-semester Total Quality Management (TQM) course for high school or community college students contains a brief overview of the definition of processes, a section on process flow diagrams, and a section on process management as well as a description of process variation. Examples are used throughout the module to make processes…

  7. Flow Dynamics of green sand in the DISAMATIC moulding process using Discrete element method (DEM)

    DEFF Research Database (Denmark)

    Hovad, Emil; Larsen, P.

    2015-01-01

    The DISAMATIC casting process production of sand moulds is simulated with DEM (discrete element method). The main purpose is to simulate the dynamics of the flow of green sand, during the production of the sand mould with DEM. The sand shot is simulated, which is the first stage of the DISAMATIC casting process. Depending on the actual casting geometry the mould can be geometrically quite complex involving e.g. shadowing effects and this is directly reflected in the sand flow during the moulding process. In the present work a mould chamber with “ribs” at the walls is chosen as a baseline geometry to emulate some of these important conditions found in the real moulding process. The sand flow is simulated with the DEM and compared with corresponding video footages from the interior of the chamber during the moulding process. The effect of the rolling resistance and the static friction coefficient is analysed and discussed in relation to the experimental findings.

  8. Flow Dynamics of green sand in the DISAMATIC moulding process using Discrete element method (DEM)

    Science.gov (United States)

    Hovad, E.; Larsen, P.; Walther, J. H.; Thorborg, J.; Hattel, J. H.

    2015-06-01

    The DISAMATIC casting process production of sand moulds is simulated with DEM (discrete element method). The main purpose is to simulate the dynamics of the flow of green sand, during the production of the sand mould with DEM. The sand shot is simulated, which is the first stage of the DISAMATIC casting process. Depending on the actual casting geometry the mould can be geometrically quite complex involving e.g. shadowing effects and this is directly reflected in the sand flow during the moulding process. In the present work a mould chamber with “ribs” at the walls is chosen as a baseline geometry to emulate some of these important conditions found in the real moulding process. The sand flow is simulated with the DEM and compared with corresponding video footages from the interior of the chamber during the moulding process. The effect of the rolling resistance and the static friction coefficient is analysed and discussed in relation to the experimental findings.

  9. Vadose zone process that control landslide initiation and debris flow propagation

    Science.gov (United States)

    Sidle, Roy C.

    2015-04-01

    Advances in the areas of geotechnical engineering, hydrology, mineralogy, geomorphology, geology, and biology have individually advanced our understanding of factors affecting slope stability; however, the interactions among these processes and attributes as they affect the initiation and propagation of landslides and debris flows are not well understood. Here the importance of interactive vadose zone processes is emphasized related to the mechanisms, initiation, mode, and timing of rainfall-initiated landslides that are triggered by positive pore water accretion, loss of soil suction and increase in overburden weight, and long-term cumulative rain water infiltration. Both large- and small-scale preferential flow pathways can both contribute to and mitigate instability, by respectively concentrating and dispersing subsurface flow. These mechanisms are influenced by soil structure, lithology, landforms, and biota. Conditions conducive to landslide initiation by infiltration versus exfiltration are discussed relative to bedrock structure and joints. The effects of rhizosphere processes on slope stability are examined, including root reinforcement of soil mantles, evapotranspiration, and how root structures affect preferential flow paths. At a larger scale, the nexus between hillslope landslides and in-channel debris flows is examined with emphasis on understanding the timing of debris flows relative to chronic and episodic infilling processes, as well as the episodic nature of large rainfall and related stormflow generation in headwater streams. The hydrogeomorphic processes and conditions that determine whether or not landslides immediately mobilize into debris flows is important for predicting the timing and extent of devastating debris flow runout in steep terrain. Given the spatial footprint of individual landslides, it is necessary to assess vadose zone processes at appropriate scales to ascertain impacts on mass wasting phenomena. Articulating the appropriate level of detail of small-scale vadose zone processes into landslide models is a particular challenge. As such, understanding flow pathways in regoliths susceptible to mass movement is critical, including distinguishing between conditions conducive to vertical recharge of water through relatively homogeneous soil mantles and conditions where preferential flow dominates - either by rapid infiltration and lateral flow through interconnected preferential flow networks or via exfiltration through bedrock fractures. These different hydrologic scenarios have major implications for the occurrence, timing, and mode of slope failures.

  10. Comparative Study of Forward and Backward Flow Forming Process using Finite Element Analysis

    Directory of Open Access Journals (Sweden)

    R.J. Bhatt

    2015-06-01

    Full Text Available Flow forming is a well known technique to produce cartridge case, rocket nose cones, rocket launcher casing etc. for defense industry. As the flow forming is the non linear plastic deformation process, it is required to understand the forces encountered and the strain distributions during the process for the efficient and successful product manufacturing. As it is a non linear plastic deformation process, still the force and strain distribution prediction is quite difficult. So that an attempt is made to predict the forces, stress, strain distributions in the present work, analysis has been carried out using ABAQUS/Explicit for forward and backward strategies. The work material has been taken as AA6063 due to its lighter weight, higher formability, ease of availability and versatile applications in aerospace and defense industry. The forces (axial, radial and circumferential acting during the process have been obtained and reported along with the strain distribution in the length and thickness. It has been found that the axial and radial forces are higher in forward flow forming. The circumferential force is found higher in backward flow forming. Moreover plastic strain distribution along the thickness is found higher in forward flow forming and along length it is found higher in backward flow forming. The study will help to identify suitable strategy before actual production for different material and process conditions.

  11. Manufacturing process planning optimisation in reconfigurable multiple parts flow lines

    OpenAIRE

    Ismail, N.; F. Musharavati; A.S.M. Hamouda; Ramli, A. R

    2008-01-01

    Purpose: This paper explores the capabilities of genetic algorithms in handling optimization of the criticalissues mentioned above for the purpose of manufacturing process planning in reconfigurable manufacturingactivities. Two modified genetic algorithms are devised and employed to provide the best approximate processplanning solution. Modifications included adapting genetic operators to the problem specific knowledge andimplementing application specific heuristics to enhance the search effi...

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

    OpenAIRE

    Barnickel, N.; Böttcher, 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 ...

  13. 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

  14. Process Flow Sheet Generation & Design through a Group Contribution Approach

    DEFF Research Database (Denmark)

    d'Anterroches, Loïc

    2006-01-01

    Denne afhandling beskriver udviklingen af et framework til opstilling og design af proces flowsheet ved hjælp af en systematisk strategi for Computer Aided Flowsheet Design (CAFD). Det udviklede framework omfatter formulering, løsning og analyse af CAFD problemer baseret på et koncept med procesgrupper som kan repræsentere en enkelt enhedsoperation eller en række enhedsoperationer på samme måde som en molekylgruppe kan repræsentere et atom eller en gruppe af atomer. Flowsheet for kemiske process...

  15. Processing the ground vibration signal produced by debris flows: the methods of amplitude and impulses compared

    Science.gov (United States)

    Arattano, M.; Abancó, C.; Coviello, V.; Hürlimann, M.

    2014-12-01

    Ground vibration sensors have been increasingly used and tested, during the last few years, as devices to monitor debris flows and they have also been proposed as one of the more reliable devices for the design of debris flow warning systems. The need to process the output of ground vibration sensors, to diminish the amount of data to be recorded, is usually due to the reduced storing capabilities and the limited power supply, normally provided by solar panels, available in the high mountain environment. There are different methods that can be found in literature to process the ground vibration signal produced by debris flows. In this paper we will discuss the two most commonly employed: the method of impulses and the method of amplitude. These two methods of data processing are analyzed describing their origin and their use, presenting examples of applications and their main advantages and shortcomings. The two methods are then applied to process the ground vibration raw data produced by a debris flow occurred in the Rebaixader Torrent (Spanish Pyrenees) in 2012. The results of this work will provide means for decision to researchers and technicians who find themselves facing the task of designing a debris flow monitoring installation or a debris flow warning equipment based on the use of ground vibration detectors.

  16. Overview of the Dissertation Process within the Framework of Flow Theory: A Qualitative Study

    Science.gov (United States)

    Cakmak, Esra; Oztekin, Ozge; Isci, Sabiha; Danisman, Sahin; Uslu, Fatma; Karadag, Engin

    2015-01-01

    The purpose of this study is to examine the flow of doctoral students who are also research assistants and in the dissertation process. The study was designed using the case study method. The case undertaken in the study was the dissertation process. Eleven participants were selected into the study using maximum variation sampling. Face-to-face,…

  17. 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.)

  18. 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

  19. 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.

  20. 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.

  1. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Yortsos, Yanis C.

    2001-08-07

    This project 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.

  3. 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.

  4. 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)

  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. Flow regime analyses during the filling stage in powder metallurgy processes: experimental study and numerical modelling

    OpenAIRE

    Cante Terán, Juan Carlos; Riera Colom, María Dolores; Oliver Olivella, Xavier; Prado Pozuelo, José Manuel

    2011-01-01

    Experimental and numerical studies of powder flow during the die filling stage in powder metallurgy cold compaction processes are presented. An experimental setting consisting of a horizontal pneumatically activated shoe, a vertical die and high-speed video system has been designed. The experiments show the existence of three flow regimes: continuous, transitory and discrete, which are identified in terms of the particle size, the morphology and the speed of the shoe. ...

  7. 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

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

    OpenAIRE

    SMITA ACHARYA, PRAGATI GUPTA, M.A.MUJAWAR

    2013-01-01

    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...

  9. 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...

  10. A numerical investigation of the resin flow front tracking applied to the RTM process

    OpenAIRE

    Jeferson Avila Souza; Luiz Alberto Oliveira Rocha; Sandro Campos Amico; José Viriato Coelho Vargas

    2011-01-01

    Resin Transfer Molding (RTM) is largely used for the manufacturing of high-quality composite components and the key stage during processing is the resin infiltration. The complete understanding of this phenomenon is of utmost importance for efficient mold construction and the fast production of high quality components. This paper investigates the resin flow phenomenon within the mold. A computational application was developed to track the resin flow-front position, which uses a finite volume ...

  11. 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.

  12. Suppression of flow pulsation activity by relaxation process of additive effect on viscous media transport

    Science.gov (United States)

    Kharlamov, S.; Dedeyev, P.; Meucci, L.; Shenderova, I.; Manastirniy, A.; Usenko, M.

    2015-11-01

    The article presents the analysis of the processes occurring together with the turbulent transfer of impulse in mixture of hydrocarbon fluid and polymer solutions (anti-turbulent additives). The study evaluates complex shear flows by popular theoretical and practical methods. Understanding of hydrodynamic and dissipative effects of laminar-turbulent transition tightening and turbulence suppression is provided. The peculiarities of "thin" flow structure in pipeline zones with complex shape walls are evaluated. Recommendations to forecast the local flow parameters, calculation of hydraulic resistance are given.

  13. Preliminary flashing multiphase flow analysis with application to letdown valves in coal-conversion processes

    Energy Technology Data Exchange (ETDEWEB)

    Ott, L. J.; Khan, A. A.

    1982-09-01

    As part of the Oak Ridge National Laboratory's technical support to large coal liquefaction projects, attempts have been made to (1) develop the methodology for characterizing and predicting multicomponent, multiphase, non-Newtonian flow behavior within letdown valves and devices, and (2) analyze the fluid flow in the entire letdown region of the process. An engineering model that can be used in the analysis of multicomponent, multiphase, flashing, flowing systems has been developed. A preliminary version of a user-oriented computer code for this model has been developed and is fully described.

  14. Power diagrams and their applications

    CERN Document Server

    van Manen, M; Manen, Martijn van; Siersma, Dirk

    2005-01-01

    We remark that the power diagrams from computer science are the spines of amoebas in algebraic geometry, or the hypersurfaces in tropical geometry. Our concept of a Morse poset generalizes to power diagrams. We show that there exists a discrete Morse function on the coherent triangulation, dual to the power diagram, such that its critical set equals the Morse poset of the power diagram. In the final section we use Maslov dequantization to compute the medial axis.

  15. The Massive Thermal Basketball Diagram

    CERN Document Server

    Andersen, J O; Strickland, Michael T; Andersen, Jens O.; Braaten, Eric; Strickland, Michael

    2000-01-01

    The "basketball diagram" is a three-loop vacuum diagram for a scalar fieldtheory that cannot be expressed in terms of one-loop diagrams. We calculatethis diagram for a massive scalar field at nonzero temperature, reducing it toexpressions involving three-dimensional integrals that can be easily evaluatednumerically. We use this result to calculate the free energy for a massivescalar field with a phi^4 interaction to three-loop order.

  16. Evaluation of biomass gasification in a ternary diagram

    International Nuclear Information System (INIS)

    The present paper addresses the development of an alternative approach to illustrate biomass gasification in a ternary diagram which is constructed using data from thermodynamic equilibrium modeling of air-blown atmospheric wood gasification. It allows the location of operation domains of slagging entrained-flow, fluidized-bed/dry-ash entrained-flow and fixed/moving-bed gasification systems depending on technical limitations mainly due to ash melting behavior. Performance parameters, e.g. cold gas efficiency or specific syngas production, and process parameters such as temperature and carbon conversion are displayed in the diagram depending on the three independent mass flows representing (1) the gasifying agent, (2) the dry biomass and (3) the moisture content of the biomass. The graphical approach indicates the existence of maxima for cold gas efficiency (84.9%), syngas yield (1.35 m3 (H2 + CO STP)/kg (waf)) and conversion of carbon to CO (81.1%) under dry air-blown conditions. The fluidized-bed/dry-ash entrained-flow processes have the potential to reach these global maxima since they can operate in the identified temperature range from 700 to 950 °C. Although using air as a gasifying agent, the same temperature range posses a potential of H2/CO ratios up to 2.0 at specific syngas productions of 1.15 m3 (H2 + CO STP)/kg (waf). Fixed/moving-bed and fluidized-bed systems can approach a dry product gas LHV from 3.0 to 5.5 MJ/m3 (dry STP). The ternary diagram was also used to study the increase of gasifying agent oxygen fraction from 21 to 99 vol.%. While the dry gas LHV can be increased significantly, the maxima of cold gas efficiency (+6.5%) and syngas yield (+7.4%) are elevated only slightly. - Highlights: • Novel graphical approach for comprehensive assessment of biomass gasification. • Parameters fields for temperature, conversion, cold gas efficiency, syngas yield etc. • Identification of operation ranges for entrained, fluid and moving-bed gasifiers. • Visualization of the influence of oxygen enrichment in gasifying agent

  17. Diagramming Complex Activities

    DEFF Research Database (Denmark)

    Andersen, Peter Bøgh

    2005-01-01

    We increasingly live in heterogeneous ever-changing webs of activities where human actions are intertwined with events created by automatic machines.  In order to make such webs understandable to its human participants, their structure should be represented by displays emphasizing their action aspect. The paper suggests thematic roles as a semantics for actions, argues that a selection of well-known diagramming techniques can be defined within this theory, and uses the theory to discuss new issu...

  18. Tectonic discrimination diagrams revisited

    OpenAIRE

    Vermeesch, P.

    2006-01-01

    The decision boundaries of most tectonic discrimination diagrams are drawn by eye. Discriminant analysis is a statistically more rigorous way to determine the tectonic affinity of oceanic basalts based on their bulk-rock chemistry. This method was applied to a database of 756 oceanic basalts of known tectonic affinity ( ocean island, mid-ocean ridge, or island arc). For each of these training data, up to 45 major, minor, and trace elements were measured. Discriminant analysis assumes multivar...

  19. The Tinsley diagram revisited

    CERN Document Server

    Leonard, S; Leonard, Stephen; Lake, Kayll

    1995-01-01

    Motivated by the recent determinations of the Hubble constant (H_0) from observations of Cepheid variables in NGC4571 and M100, we plot the Tinsley diagram with level curves of the cosmological constant (\\Lambda). Based on current estimates of the absolute ages of globular clusters we conclude that \\Lambda > 0 and, irrespective of the background spatial curvature, the universe will not recollapse. These conclusions hold for both relativistic and Newtonian models and are {\\it independent} of the density parameter.

  20. Compressing Binary Decision Diagrams

    DEFF Research Database (Denmark)

    Hansen, Esben Rune; Satti, Srinivasa Rao; Tiedemann, Peter

    2008-01-01

    The paper introduces a new technique for compressing Binary Decision Diagrams in those cases where random access is not required. Using this technique, compression and decompression can be done in linear time in the size of the BDD and compression will in many cases reduce the size of the BDD to 1-2 bits per node. Empirical results for our compression technique are presented, including comparisons with previously introduced techniques, showing that the new technique dominate on all tested instan...

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

    OpenAIRE

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

  2. Study on the air flow field of the drawing conduit in the spunbonding process

    Directory of Open Access Journals (Sweden)

    Wu Li-Li

    2015-01-01

    Full Text Available The air flow field of the drawing conduit in the spunbonding process has a great effect on the polymer drawing, the filament diameter and orientation. A numerical simulation of the process is carried out, and the results are compared with the experimental data, showing good accuracy of the numerical prediction. This research lays an important foundation for the optimal design of the drawing conduit in the spunbonding process.

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

    Energy Technology Data Exchange (ETDEWEB)

    Magnusson, D. [European Commission, Joint Research Center, Institute for Transuranium Elements, Postfach 2340 D-76125 Karlsruhe (Germany)]|[Chalmers University of Technology, Nuclear Chemistry, Deparment of Chemical and Biological Engineering, Gothenburg (Sweden); Christiansen, B.; Glatz, J.P.; Malmbeck, R.; Serrano-Purroy, D. [European Commission, Joint Research Center, Institute for Transuranium Elements, Postfach 2340 D-76125 Karlsruhe (Germany); Modolo, G. [Forschungszentrum Juelich, Institute for Energy Research, Safety Research and Reactor Technology, D-52425 Juelich (Germany); Sorel, C. [Commissariat a l' Energie Atomique Valrho (CEA), DRCP/SCPS, BP17171, 30207 Bagnols-sur-Ceze (France)

    2008-07-01

    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 CyMe{sub 4}- 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)

  4. Transient hydraulic characteristic of nuclear reactor coolant pump in variable flow transient process

    International Nuclear Information System (INIS)

    For the study on the transient hydraulic characteristics and internal flow mechanism of the nuclear reactor coolant pump in the transient process from design operation conditions to off-design conditions, the variable flow transient characteristics of centrifugal pump impeller passageway were simulated by using CFX software. The results show that during the variable flow transition, the distribution of pressure pulsation of the nuclear reactor coolant pump along the circumference direction is non- uniform. The pressure pulsation trends to rise gradually to reach the maximum value and then fall, basically following a sine-shape changing law. The times of transient pressure fluctuation change are equal to the times of rotor-stator interference between the vane and the guide vane. The closer monitoring point to the intersection surface between the vane and the guide blade is, the greater the pressure fluctuation is. Because of the attack angle, the speed of the impeller passageway first falls and then rises. The guide vane not only transfers the kinetic energy to pressure energy, but also effectively reduces the pressure pulsation amplitude. During the transition to small flow, flow reducing causes the secondary backflow to occur near the outlet of impeller and in turn leads the amplitude of flow velocity variation in the flow channel of impeller to increase with flow decrease. (authors)

  5. 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.

  6. Initiation processes for run-off generated debris flows in the Wenchuan earthquake area of China

    Science.gov (United States)

    Hu, W.; Dong, X. J.; Xu, Q.; Wang, G. H.; van Asch, T. W. J.; Hicher, P. Y.

    2016-01-01

    The frequency of huge debris flows greatly increased in the epicenter area of the Wenchuan earthquake. Field investigation revealed that runoff during rainstorm played a major role in generating debris flows on the loose deposits, left by coseismic debris avalanches. However, the mechanisms of these runoff-generated debris flows are not well understood due to the complexity of the initiation processes. To better understand the initiation mechanisms, we simulated and monitored the initiation process in laboratory flume test, with the help of a 3D laser scanner. We found that run-off incision caused an accumulation of material down slope. This failed as shallow slides when saturated, transforming the process into debris in a second stage. After this initial phase, the debris flow volume increased rapidly by a chain of subsequent cascading processes starting with collapses of the side walls, damming and breaching, leading to a rapid widening of the erosion channel. In terms of erosion amount, the subsequent mechanisms were much more important than the initial one. The damming and breaching were found to be the main reasons for the huge magnitude of the debris flows in the post-earthquake area. It was also found that the tested material was susceptible to excess pore pressure and liquefaction in undrained triaxial, which may be a reason for the fluidization in the flume tests.

  7. 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.)

  8. Flow Dynamics of green sand in the DISAMATIC moulding process using Discrete element method (DEM)

    DEFF Research Database (Denmark)

    Hovad, Emil; Larsen, P.; Walther, Jens Honore; Thorborg, Jesper; Hattel, Jesper Henri

    2015-01-01

    The DISAMATIC casting process production of sand moulds is simulated with DEM (discrete element method). The main purpose is to simulate the dynamics of the flow of green sand, during the production of the sand mould with DEM. The sand shot is simulated, which is the first stage of the DISAMATIC casting process. Depending on the actual casting geometry the mould can be geometrically quite complex involving e.g. shadowing effects and this is directly reflected in the sand flow during the moulding...

  9. Influence diagrams for contextual information retrieval

    OpenAIRE

    Tamine-Lechani, Lynda; Boughanem, Mohand

    2006-01-01

    The purpose of contextual information retrieval is to make some exploration towards designing user specific search engines that are able to adapt the retrieval model to the variety of differences on user's contexts. In this paper we propose an influence diagram based retrieval model which is able to incorporate contexts, viewed as user's long-term interests into the retrieval process.

  10. 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.

  11. Quantitative analysis of flow processes in a sand using synchrotron-based X-ray microtomography

    DEFF Research Database (Denmark)

    Wildenschild, Dorthe; Hopmans, J.W.

    2005-01-01

    Pore-scale multiphase flow experiments were developed to nondestructively visualize water flow in a sample of porous material using X-ray microtomography. The samples were exposed to similar boundary conditions as in a previous investigation, which examined the effect of initial flow rate on observed dynamic effects in the measured pressure-saturation curves; a significantly higher residual and higher capillary pressures were found when the sample was drained fast using a high air-phase pressure. Prior work applying the X-ray microtomography technique to pore-scale multiphase flow problems has been of a mostly qualitative nature and no experiments have been presented in the existing literature where a truly quantitative approach to investigating the multiphase flow process has been taken, including a thorough image-processing scheme. The tomographic images presented here show, both by qualitative comparison and quantitative analysis in the form of a nearest neighbor analysis, that the dynamic effects seen in previous experiments are likely due to the fast and preferential drainage of large pores in the sample. Once a continuous drained path has been established through the sample, further drainage of the remaining pores, which have been disconnected from the main flowing water continuum, is prevented.

  12. Studies of thermohydrologic flow processes using TOUGH2. Yucca Mountain Site Characterization Project

    International Nuclear Information System (INIS)

    Coupled thermal and hydrologic flow processes have been recognized as important factors in the evaluation of Yucca Mountain as a potential repository for high-level radioactive wastes. As a result, several models and numerical codes such as TOUGH2 have been used to investigate the thermohydrologic conditions near a potential nuclear waste repository. However, very few of these models have been tested through laboratory or field scale studies. This work has therefore focused on modeling well-controlled experiments of non-isothermal flow processes in porous media at different scales to serve two primary objectives: (1) identify processes that are potentially important to thermal and hydrologic transport at Yucca Mountain and (2) build confidence in models and codes through combined experimental and numerical studies of thermohydrologic behavior at different scales and conditions. In this report, three independent studies of thermohydrologic flow processes at laboratory and field scales are presented. The experiments and field studies that are presented here were performed independently of this work. The main focus of this report was to use the numerical code TOUGH2 to simulate the non-isothermal flow behavior observed in each experiment to generate understanding of the thermohydrologic processes and to gain confidence in the code. TOUGH2 was chosen due to its current use in calculations associated with Yucca Mountain and its capability of modeling the coupled transport of air, water, vapor, and heat in porous media

  13. 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.

  14. Diagramming Word Problems: A Strategic Approach for Instruction

    Science.gov (United States)

    van Garderen, Delinda; Scheuermann, Amy M.

    2015-01-01

    While often recommended as a strategy to use in order to solve word problems, drawing a diagram is a complex process that requires a good depth of understanding. Many middle school students with learning disabilities (LD) often struggle to use diagrams in an effective and efficient manner. This article presents information for teaching middle…

  15. Conservative generalized bifurcation diagrams

    Energy Technology Data Exchange (ETDEWEB)

    Manchein, Cesar, E-mail: cmanchein@gmail.com [Departamento de Física, Universidade do Estado de Santa Catarina, 89219-710 Joinville (Brazil); Beims, Marcus W., E-mail: mbeims@fisica.ufpr.br [Departamento de Física, Universidade Federal do Paraná, 81531-980 Curitiba (Brazil)

    2013-04-01

    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 ?{sub 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.

  16. 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.

  17. The diagram development for Computer Added Control and Monitoring system of drilling

    Science.gov (United States)

    Epikhin, A. V.; Mikhalev, R. S.; Anisimov, A. V.; Ulyanova, O. S.

    2015-11-01

    The paper is concerned with the first stage of the extensive research aimed at developing design-automation system and well drilling process control. The proposed system is going to have some advantages over modern analogues, such as economic analysis at all levels, active engineering staff feedback, precedent-related principle for recommendations, etc. It will essentially reduce the risk of human errors and also optimize the well construction process from design to commissioning. The paper considers the results of the first design stage in a form of flow diagrams.

  18. On Efficient Multigrid Methods for Materials Processing Flows with Small Particles

    Science.gov (United States)

    Thomas, James (Technical Monitor); Diskin, Boris; Harik, VasylMichael

    2004-01-01

    Multiscale modeling of materials requires simulations of multiple levels of structural hierarchy. The computational efficiency of numerical methods becomes a critical factor for simulating large physical systems with highly desperate length scales. Multigrid methods are known for their superior efficiency in representing/resolving different levels of physical details. The efficiency is achieved by employing interactively different discretizations on different scales (grids). To assist optimization of manufacturing conditions for materials processing with numerous particles (e.g., dispersion of particles, controlling flow viscosity and clusters), a new multigrid algorithm has been developed for a case of multiscale modeling of flows with small particles that have various length scales. The optimal efficiency of the algorithm is crucial for accurate predictions of the effect of processing conditions (e.g., pressure and velocity gradients) on the local flow fields that control the formation of various microstructures or clusters.

  19. 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.

  20. 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.

  1. Structure and Microhardness of Steel Samples after Pulse Plasma Flows Processing

    OpenAIRE

    Anuar Zhukeshov; Asylgul Gabdullina; Assem Amrenova; Svetlana Pak

    2013-01-01

    The phase structure of surfaces of steel samples, modified by pulse plasma processing, was analyzed using XRD and metallographic methods. It has been shown, that after pulse plasma processing under different conditions a modified structure consisting of three new phases, including austenite, iron nitride and carbide, is formed. The dependence of phase transition and microhardness on plasma flow parameters has been studied. A sharp decrease in the dimensions of ferrite crystallites after the ...

  2. Post-processing of a low-flow forecasting system in the Thur basin (Switzerland)

    Science.gov (United States)

    Bogner, Konrad; Joerg-Hess, Stefanie; Bernhard, Luzi; Zappa, Massimiliano

    2015-04-01

    Low-flows and droughts are natural hazards with potentially severe impacts and economic loss or damage in a number of environmental and socio-economic sectors. As droughts develop slowly there is time to prepare and pre-empt some of these impacts. Real-time information and forecasting of a drought situation can therefore be an effective component of drought management. Although Switzerland has traditionally been more concerned with problems related to floods, in recent years some unprecedented low-flow situations have been experienced. Driven by the climate change debate a drought information platform has been developed to guide water resources management during situations where water resources drop below critical low-flow levels characterised by the indices duration (time between onset and offset), severity (cumulative water deficit) and magnitude (severity/duration). However to gain maximum benefit from such an information system it is essential to remove the bias from the meteorological forecast, to derive optimal estimates of the initial conditions, and to post-process the stream-flow forecasts. Quantile mapping methods for pre-processing the meteorological forecasts and improved data assimilation methods of snow measurements, which accounts for much of the seasonal stream-flow predictability for the majority of the basins in Switzerland, have been tested previously. The objective of this study is the testing of post-processing methods in order to remove bias and dispersion errors and to derive the predictive uncertainty of a calibrated low-flow forecast system. Therefore various stream-flow error correction methods with different degrees of complexity have been applied and combined with the Hydrological Uncertainty Processor (HUP) in order to minimise the differences between the observations and model predictions and to derive posterior probabilities. The complexity of the analysed error correction methods ranges from simple AR(1) models to methods including wavelet transformations and support vector machines. These methods have been combined with forecasts driven by Numerical Weather Prediction (NWP) systems with different temporal and spatial resolutions, lead-times and different numbers of ensembles covering short to medium to extended range forecasts (COSMO-LEPS, 10-15 days, monthly and seasonal ENS) as well as climatological forecasts. Additionally the suitability of various skill scores and efficiency measures regarding low-flow predictions will be tested. Amongst others the novel 2afc (2 alternatives forced choices) score and the quantile skill score and its decompositions will be applied to evaluate the probabilistic forecasts and the effects of post-processing. First results of the performance of the low-flow predictions of the hydrological model PREVAH initialised with different NWP's will be shown.

  3. Effects Of Thermal Exchange On Material Flow During Steel Thixoextrusion Process

    Science.gov (United States)

    Eric, Becker; Guochao, Gu; Laurent, Langlois; Raphaël, Pesci; Régis, Bigot

    2011-01-01

    Semisolid processing is an innovative technology for near net-shape production of components, where the metallic alloys are processed in the semisolid state. Taking advantage of the thixotropic behavior of alloys in the semisolid state, significant progress has been made in semisolid processing. However, the consequences of such behavior on the flow during thixoforming are still not completely understood. To explore and better understand the influence of the different parameters on material flow during thixoextrusion process, thixoextrusion experiments were performed using the low carbon steel C38. The billet was partially melted at high solid fraction. Effects of various process parameters including the initial billet temperature, the temperature of die, the punch speed during process and the presence of a Ceraspray layer at the interface of tool and billet were investigated through experiments and simulation. After analyzing the results thus obtained, it was identified that the aforementioned parameters mainly affect thermal exchanges between die and part. The Ceraspray layer not only plays a lubricant role, but also acts as a thermal barrier at the interface of tool and billet. Furthermore, the thermal effects can affect the material flow which is composed of various distinct zones.

  4. 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

  5. Flow behavior of polymers during the roll-to-roll hot embossing process

    Science.gov (United States)

    Deng, Yujun; Yi, Peiyun; Peng, Linfa; Lai, Xinmin; Lin, Zhongqin

    2015-06-01

    The roll-to-roll (R2R) hot embossing process is a recent advancement in the micro hot embossing process and is capable of continuously fabricating micro/nano-structures on polymers, with a high efficiency and a high throughput. However, the fast forming of the R2R hot embossing process limits the time for material flow and results in complicated flow behavior in the polymers. This study presents a fundamental investigation into the flow behavior of polymers and aims towards the comprehensive understanding of the R2R hot embossing process. A three-dimensional (3D) finite element (FE) model based on the viscoelastic model of polymers is established and validated for the fabrication of micro-pyramids using the R2R hot embossing process. The deformation and recovery of micro-pyramids on poly(vinyl chloride) (PVC) film are analyzed in the filling stage and the demolding stage, respectively. Firstly, in the analysis of the filling stage, the temperature distribution on the PVC film is discussed. A large temperature gradient is observed along the thickness direction of the PVC film and the temperature of the top surface is found to be higher than that of the bottom surface, due to the poor thermal conductivity of PVC. In addition, creep strains are demonstrated to depend highly on the temperature and are also observed to concentrate on the top layer of the PVC film because of high local temperature. In the demolding stage, the recovery of the embossed micro-pyramids is obvious. The cooling process is shown to be efficient for the reduction of recovery, especially when the mold temperature is high. In conclusion, this research advances the understanding of the flow behavior of polymers in the R2R hot embossing process and might help in the development of the highly accurate and highly efficient fabrication of microstructures on polymers.

  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. A Neuroeconomics Analysis of Investment Process with Money Flow Information: The Error-Related Negativity.

    Science.gov (United States)

    Wang, Cuicui; Vieito, João Paulo; Ma, Qingguo

    2015-01-01

    This investigation is among the first ones to analyze the neural basis of an investment process with money flow information of financial market, using a simplified task where volunteers had to choose to buy or not to buy stocks based on the display of positive or negative money flow information. After choosing "to buy" or "not to buy," participants were presented with feedback. At the same time, event-related potentials (ERPs) were used to record investor's brain activity and capture the event-related negativity (ERN) and feedback-related negativity (FRN) components. The results of ERN suggested that there might be a higher risk and more conflict when buying stocks with negative net money flow information than positive net money flow information, and the inverse was also true for the "not to buy" stocks option. The FRN component evoked by the bad outcome of a decision was more negative than that by the good outcome, which reflected the difference between the values of the actual and expected outcome. From the research, we could further understand how investors perceived money flow information of financial market and the neural cognitive effect in investment process. PMID:26557139

  8. A Neuroeconomics Analysis of Investment Process with Money Flow Information: The Error-Related Negativity

    Science.gov (United States)

    Wang, Cuicui; Vieito, João Paulo; Ma, Qingguo

    2015-01-01

    This investigation is among the first ones to analyze the neural basis of an investment process with money flow information of financial market, using a simplified task where volunteers had to choose to buy or not to buy stocks based on the display of positive or negative money flow information. After choosing “to buy” or “not to buy,” participants were presented with feedback. At the same time, event-related potentials (ERPs) were used to record investor's brain activity and capture the event-related negativity (ERN) and feedback-related negativity (FRN) components. The results of ERN suggested that there might be a higher risk and more conflict when buying stocks with negative net money flow information than positive net money flow information, and the inverse was also true for the “not to buy” stocks option. The FRN component evoked by the bad outcome of a decision was more negative than that by the good outcome, which reflected the difference between the values of the actual and expected outcome. From the research, we could further understand how investors perceived money flow information of financial market and the neural cognitive effect in investment process. PMID:26557139

  9. 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.

  10. REPRESENTING MARKOV CHAINS WITH TRANSITION DIAGRAMS

    OpenAIRE

    Farida Kachapova

    2013-01-01

    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 cha...

  11. 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

  12. Application of Artificial Vision in flow redirection during filling of Liquid Composite Molding processes

    Science.gov (United States)

    Montés, N.; Sanchez, F.; García, J. A.; Falcó, A.; Tornero, J.; Chinesta, F.

    2007-04-01

    The control techniques applied in Liquid Composite Molding processes have been extensively worked out by many different research groups abroad. In this work, the original use of artificial vision technology in order to redirect the flow path during mold filling appears as a major objective of online control strategy. In this study, a process performance index developed in a previous work is used to define the mold gate opening sequence. The Vacuum Assisted Resin Transfer Molding (VARTM) and Vacuum Assisted Resin Infusion (VARI) have been selected as the main processes of study. The expert system will make use of numerical simulation in order to obtain a previous physical understanding of the flow behaviour in different manufacturing conditions. Some examples of the installation are presented and discussed.

  13. Diagrams and Proofs in Analysis

    DEFF Research Database (Denmark)

    Carter, Jessica M H Grund

    2010-01-01

    The article discusses the role of diagrams in mathematical reasoning based on a case study in analysis.   In the presented example certain combinatorial expressions were first found by using diagrams. In the published proofs the pictures are replaced by reasoning about permutation groups. This paper argues that, even though the diagrams are not present in the papers, they still play a role in the formulation of the proofs. It is shown that they play a role in concept formation as well as represe...

  14. An efficient continuous flow process for the synthesis of a non-conventional mixture of fructooligosaccharides.

    Science.gov (United States)

    Zambelli, Paolo; Tamborini, Lucia; Cazzamalli, Samuele; Pinto, Andrea; Arioli, Stefania; Balzaretti, Silvia; Plou, Francisco J; Fernandez-Arrojo, Lucia; Molinari, Francesco; Conti, Paola; Romano, Diego

    2016-01-01

    A sustainable and scalable process for the production of a new mixture of fructooligosaccharides (FOS) was developed using a continuous-flow approach based on an immobilized whole cells-packed bed reactor. The technological transfer from a classical batch system to an innovative flow environment allowed a significant improvement of the productivity. Moreover, the stability of this production system was ascertained by up to 7 days of continuous working. These results suggest the suitability of the proposed method for a large-scale production of the desired FOS mixture, in view of a foreseeable use as a novel prebiotic preparation. PMID:26213017

  15. 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.

  16. 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.

  17. Application of the radiotracer method of molten glass flow process identification for optimization of tank furnaces

    International Nuclear Information System (INIS)

    Examples of application of the mathematical flow model proposed by Wolf and Resnick for the glass melting process optimization have been presented. The model description of the process was verified experimentally. The tracer selection criteria have been discussed. The method of radiotracer injection and the tracer detection have been described. Parameters for the tank furnace operation have been calculated for different layouts of the furnace. From the results obtained general conclusions have been drawn and recommendations for optimizing the glass production process are presented. (author)

  18. 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...

  19. INVESTIGATION OF MULTISCALE AND MULTIPHASE FLOW, TRANSPORT AND REACTION IN HEAVY OIL RECOVERY PROCESSES

    Energy Technology Data Exchange (ETDEWEB)

    Yannis C. Yortsos

    2003-02-01

    This is final report for contract DE-AC26-99BC15211. The report describes progress made in the various thrust areas of the project, which include internal drives for oil recovery, vapor-liquid flows, combustion and reaction processes and the flow of fluids with yield stress. The report consists mainly of a compilation of various topical reports, technical papers and research reports published produced during the three-year project, which ended on May 6, 2002 and was no-cost extended to January 5, 2003. Advances in multiple processes and at various scales are described. In the area of internal drives, significant research accomplishments were made in the modeling of gas-phase growth driven by mass transfer, as in solution-gas drive, and by heat transfer, as in internal steam drives. In the area of vapor-liquid flows, we studied various aspects of concurrent and countercurrent flows, including stability analyses of vapor-liquid counterflow, and the development of novel methods for the pore-network modeling of the mobilization of trapped phases and liquid-vapor phase changes. In the area of combustion, we developed new methods for the modeling of these processes at the continuum and pore-network scales. These models allow us to understand a number of important aspects of in-situ combustion, including steady-state front propagation, multiple steady-states, effects of heterogeneity and modes of combustion (forward or reverse). Additional aspects of reactive transport in porous media were also studied. Finally, significant advances were made in the flow and displacement of non-Newtonian fluids with Bingham plastic rheology, which is characteristic of various heavy oil processes. Various accomplishments in generic displacements in porous media and corresponding effects of reservoir heterogeneity are also cited.

  20. 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)

  1. Toward a Grid Work flow Formal Composition

    Energy Technology Data Exchange (ETDEWEB)

    Hlaoui, Y. B.; BenAyed, L. J.

    2007-07-01

    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)

  2. The Impact of Rhizosphere Processes on Water Flow and Root Water Uptake

    Science.gov (United States)

    Schwartz, Nimrod; Kroener, Eva; Carminati, Andrea; Javaux, Mathieu

    2015-04-01

    For many years, the rhizosphere, which is the zone of soil in the vicinity of the roots and which is influenced by the roots, is known as a unique soil environment with different physical, biological and chemical properties than those of the bulk soil. Indeed, in recent studies it has been shown that root exudate and especially mucilage alter the hydraulic properties of the soil, and that drying and wetting cycles of mucilage result in non-equilibrium water dynamics in the rhizosphere. While there are experimental evidences and simplified 1D model for those concepts, an integrated model that considers rhizosphere processes with a detailed model for water and roots flow is absent. Therefore, the objective of this work is to develop a 3D physical model of water flow in the soil-plant continuum that take in consideration root architecture and rhizosphere specific properties. Ultimately, this model will enhance our understanding on the impact of processes occurring in the rhizosphere on water flow and root water uptake. To achieve this objective, we coupled R-SWMS, a detailed 3D model for water flow in soil and root system (Javaux et al 2008), with the rhizosphere model developed by Kroener et al (2014). In the new Rhizo-RSWMS model the rhizosphere hydraulic properties differ from those of the bulk soil, and non-equilibrium dynamics between the rhizosphere water content and pressure head is also considered. We simulated a wetting scenario. The soil was initially dry and it was wetted from the top at a constant flow rate. The model predicts that, after infiltration the water content in the rhizosphere remained lower than in the bulk soil (non-equilibrium), but over time water infiltrated into the rhizosphere and eventually the water content in the rhizosphere became higher than in the bulk soil. These results are in qualitative agreement with the available experimental data on water dynamics in the rhizosphere. Additionally, the results show that rhizosphere processes affect the spatial distribution of root water uptake. This suggests that rhizosphere processes effect root water uptake at the plant scale. Overall, these preliminary results demonstrate the impact of rhizosphere on water flow and root water uptake, and the ability of the Rhizo-RSWMS to simulate these processes. References Javaux, M., Schröder, T., Vanderborght, J., & Vereecken, H. (2008). Use of a three-dimensional detailed modeling approach for predicting root water uptake. Vadose Zone Journal, 7(3), 1079-1088.? Kroener, E., Zarebanadkouki, M., Kaestner, A., & Carminati, A. (2014). Nonequilibrium water dynamics in the rhizosphere: How mucilage affects water flow in soils. Water Resources Research, 50(8), 6479-6495.?

  3. 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 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.

  4. 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

    Directory of Open Access Journals (Sweden)

    Tiago Facchin

    2008-08-01

    Full Text Available 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.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 moments 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.

  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. 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.

  7. 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

  8. 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 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)

  9. Recent results in Ring Diagram analysis

    CERN Document Server

    Rabello-Soares, M Cristina

    2013-01-01

    The ring-diagram technique was developed by Frank Hill 25 years ago and developed quickly during the late 1990s. It is nowadays one of the most commonly used techniques in local helioseismology. The method consists in the power spectral analysis of solar acoustic oscillations on small regions (2 to 30 degrees) of the solar surface. The power spectrum resembles a set of trumpets nested inside each other and, for a given frequency, it looks like a ring, hence the technique's name. It provides information on the horizontal flow field and thermodynamic structure in the layers immediately below the photosphere. With data regularly provided by MDI (on board SOHO), GONG+ network and more recently HMI (on SDO), many important results have been achieved. In recently years, these results include estimations of the meridional circulation and its evolution with solar cycle; flows associated with active regions, as well as, flow divergence and vorticity; and thermal structure beneath and around active regions. Much progre...

  10. Numerical simulations of the laminar-turbulent transition process in plane Poiseuille flow

    International Nuclear Information System (INIS)

    Laminar-turbulent transition in plane Poiseuille flow is simulated by numerical integration of the time-dependent three-dimensional Navier-Stokes equations for incompressible flow. The mathematical model of a spatially periodic, timewise developing flow in a moving frame of reference is used to match vibrating-ribbon experiments of Nishioka et al. The numerical discretisation is based on a spectral method with Fourier and Chebyshev polynomial expansions in space and second order finite differences in time. The pressure is calculated using a new method which enforces incompressibility and boundary conditions exactly. This is achieved by deriving the correct boundary conditions for the pressure Poisson equation. The numerical results obtained for two-dimensional finite amplitude disturbances are consistent with nonlinear stability theory. The time-periodic secondary flow is attained by the time-dependent calculation with reasonable accuracy after a long quasi-steady state. No sign of two-dimensional instability, but strong three-dimensional instability as well of the periodic secondary flow as of the quasi-steady state is found. This secondary three-dimensional instability is shown to be responsible for transition. It is shown that the three-dimensional simulations presented here reproduce the experimentally observed transition process up to the spike stage. Detailed comparisons with measurements of mean velocity, rms-values of fluctuation and instantaneous velocity distribution reveal very satisfactory agreement. The formation of peak-valley structure, longitudinal vortices, local high-shear layers and distinct spike-type signals is shown. In addition, the three-dimensional flow field structure before breakdown is investigated. An array of horseshoe vortices similar to those inferred from boundary layer flow visualization experiments is found. Spike signals are produced by local accumulations of low-speed fluid in the downstream loops of these vortices. (orig.)

  11. Constructing set-valued fundamental diagrams from jamiton solutions in second order traffic models

    CERN Document Server

    Seibold, Benjamin; Kasimov, Aslan R; Rosales, Rodolfo Ruben

    2012-01-01

    Fundamental diagrams of vehicular traffic flow are generally multi-valued in the congested flow regime. We show that such set-valued fundamental diagrams can be constructed systematically from simple second order macroscopic traffic models, such as the classical Payne-Whitham model or the inhomogeneous Aw-Rascle-Zhang model. These second order models possess nonlinear traveling wave solutions, called jamitons, and the multi-valued parts in the fundamental diagram correspond precisely to jamiton-dominated solutions. This study shows that transitions from function-valued to set-valued parts in a fundamental diagram arise naturally as intrinsic properties of well-known second order models.

  12. 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.

  13. A numerical investigation of the resin flow front tracking applied to the RTM process

    Scientific Electronic Library Online (English)

    Jeferson Avila, Souza; Luiz Alberto Oliveira, Rocha; Sandro Campos, Amico; José Viriato Coelho, Vargas.

    2011-09-01

    Full Text Available Resin Transfer Molding (RTM) is largely used for the manufacturing of high-quality composite components and the key stage during processing is the resin infiltration. The complete understanding of this phenomenon is of utmost importance for efficient mold construction and the fast production of high [...] quality components. This paper investigates the resin flow phenomenon within the mold. A computational application was developed to track the resin flow-front position, which uses a finite volume method to determine the pressure field and a FAN (Flow Analysis Network) technique to track the flow front. The mass conservation problem observed with traditional FE-CV (Finite Element-Control Volume) methods is also investigated and the use of a finite volume method to minimize this inconsistency is proposed. Three proposed case studies are used to validate the methodology by direct comparison with analytical and a commercial software solutions. The results show that the proposed methodology is highly efficient to determine the resin flow front, showing an improvement regarding mass conservation across volumes.

  14. A numerical investigation of the resin flow front tracking applied to the RTM process

    Directory of Open Access Journals (Sweden)

    Jeferson Avila Souza

    2011-09-01

    Full Text Available Resin Transfer Molding (RTM is largely used for the manufacturing of high-quality composite components and the key stage during processing is the resin infiltration. The complete understanding of this phenomenon is of utmost importance for efficient mold construction and the fast production of high quality components. This paper investigates the resin flow phenomenon within the mold. A computational application was developed to track the resin flow-front position, which uses a finite volume method to determine the pressure field and a FAN (Flow Analysis Network technique to track the flow front. The mass conservation problem observed with traditional FE-CV (Finite Element-Control Volume methods is also investigated and the use of a finite volume method to minimize this inconsistency is proposed. Three proposed case studies are used to validate the methodology by direct comparison with analytical and a commercial software solutions. The results show that the proposed methodology is highly efficient to determine the resin flow front, showing an improvement regarding mass conservation across volumes.

  15. Simulación de eventos discretos y líneas de balance, aplicadas al mejoramiento del proceso constructivo de la cimentación de un edificio / Discrete Event Simulation and Line of Balance Diagram, Applied to the Improvement of the Foundation Construction Process

    Scientific Electronic Library Online (English)

    Adriana, Gómez Cabrera; Natalia, Quintana Pulido; Jorge, Orlando Ávila Díaz.

    2015-01-01

    Full Text Available El objeto de este trabajo fue establecer propuestas de mejoramiento al proceso de planeación de tiempos y costos en la etapa de cimentación de un edificio, a partir de la integración de herramientas como simulación de eventos discretos, programación con líneas de balance y metodologías Building Info [...] rmation Modeling - BIM. A partir de mediciones en campo se levantó información para la elaboración de un modelo de simulación de eventos discretos que imitara el proceso constructivo real. Se propusieron y modelaron alternativas de mejora, a partir de los principios de la filosofía Lean Construction y la programación de líneas de balance encontrando reducciones en tiempo y costo. También se realizó la animación virtual de las alternativas a partir de metodologías BIM. Se concluye que la integración de las herramientas utilizadas es de gran utilidad en la planeación y toma de decisiones en un proyecto civil. Abstract in english The objective of this study is to propose a new method to enhance the time- and cost-planning process for the construction of building foundations via integration of discrete-event simulation, line-of-balance diagram, and Building Information Modeling (BIM) tools. In order to calibrate a discrete-ev [...] ent simulation model, field measurements of workflow, resource consumption, activity duration, and restrictions were obtained from real construction projects. Based on Lean Construction methods and line-of-balance diagrams, which allow reduction in time and cost, a number of planning alternatives were proposed. In addition, virtual animation of such alternatives was performed through BIM methodologies. It is concluded that planning tool integration is a robust technique for planning and decision-making in civil engineering projects.

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

    Energy Technology Data Exchange (ETDEWEB)

    Satoh, Keita; Kameda, Masaharu [Tokyo Univ. of Agriculture and Technology, Koganei (Japan). Faculty of Technology; Kato, Mitsutoshi [Graduate School , Tokyo Univ. of Agriculture and Technology, Koganei (Japan)

    2000-07-01

    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)

  17. Monte Carlo simulation of sputter-deposition and etching in plasma processing rarefied flows

    International Nuclear Information System (INIS)

    The present study is focused on applying the Monte Carlo particle simulation method to the estimation of the sputter-deposition and etching rates by calculation of a discharge gas flow field and material atoms transport. The particle approach is used to manage with strongly nonequilibrium and inhomogeneous physico-chemical processes involved. The reason is in a low operating pressure (typically less than 7 Pa) in the apparatus, which leads to the mean free path ? greater than 1 mm. And since the characteristic size is of the order of L?100 mm, the gas flow is in the transition regime, as characterized by the Knudsen number Kn = ?/L ? 0.01. The simulation is based on some reasonable assumptions to be eventually substituted (as we hope) by output data from forthcoming calculations of a discharge plasma and surface and gas phase chemistry. The goal will be to close the 3-D mathematical model for plasma processing

  18. Processing flow visualisation records by correlation coefficient evaluation in sub-images.

    Czech Academy of Sciences Publication Activity Database

    Tesa?, Václav; N?ni?ka, Václav

    Prague : Institute of Thermomechanics AS CR, v. v. i., 2010 - (Zolotarev, I.), s. 153-154 ISBN 978-80-87012-26-0. [ENGINEERING MECHANICS 2010. Svratka (CZ), 10.05.2010-13.05.2010] R&D Projects: GA ?R GA101/07/1499; GA AV ?R IAA200760705 Institutional research plan: CEZ:AV0Z20760514 Keywords : flow visualisation * correlation coefficient * infrasound * image processing Subject RIV: BK - Fluid Dynamics

  19. Deterministic flows of order-parameters in stochastic processes of quantum Monte Carlo method

    OpenAIRE

    Inoue, Jun-Ichi

    2010-01-01

    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 ($d(=\\infty)$-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 s...

  20. 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...

  1. 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...

  2. Centrifugal fertiliser spreading : velocity and mass flow distribution measurement by image processing

    OpenAIRE

    Villette, S; Gée, C.; Piron, E.; de Martin, R; Miclet, D.; Paindavoine, M.

    2010-01-01

    This paper investigates the use of a new imaging system to measure the velocity and the mass flow distribution of fertiliser granules spread by a centrifugal device. The new acquisition system consists of a digital camera placed above the disc so that its view axis corresponds to the disc axle. This provides useful geometrical properties to develop a simple and efficient image processing. The technique provides a global estimation of the spreading characteristics for the whole fertiliser ...

  3. Selection of the economic objective function for the optimization of process flow sheets

    OpenAIRE

    Novak-Pintari?, Zorka; Kravanja, Zdravko

    2012-01-01

    This paper highlights the problem of selecting the most suitable economic optimization criteria for mathematical programming approaches to the synthesis, design, and optimization of chemical process flow sheets or their subsystems. Minimization of costs and maximization of profit are the most frequently used economic criteria in technical papers. However, there are manyother financial measures which can lead to different optimal solutions if applied in the objective function. This paper descr...

  4. Fluid queues driven by a birth and death process with alternating flow rates

    OpenAIRE

    Parthasarathy P. R.; Vijayashree K. V.; Lenin R. B.

    2004-01-01

    Fluid queue driven by a birth and death process (BDP) with only one negative effective input rate has been considered in the literature. As an alternative, here we consider a fluid queue in which the input is characterized by a BDP with alternating positive and negative flow rates on a finite state space. Also, the BDP has two alternating arrival rates and two alternating service rates. Explicit expression for the distribution function of the buffer occupancy is obtained. The case where the s...

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

    Directory of Open Access Journals (Sweden)

    Kit D. 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.

  6. Flow Behavior and Processing Maps of a Low-Carbon Steel During Hot Deformation

    Science.gov (United States)

    Yang, Xiawei; Li, Wenya

    2015-12-01

    The hot isothermal compression tests of a low-carbon steel containing 0.20 pct C were performed in the temperature range of 973 K to 1273 K (700 °C to 1000 °C) and at the strain rate range of 0.001 to 1 s-1. The results show that the flow stress is dependent on deformation temperature and strain rate (decreasing with increasing temperature and/or increasing with increasing strain rate). The flow stress predicted by Arrhenius-type and artificial neural network models were both in a good agreement with experimental data, while the prediction accuracy of the latter is better than the former. A processing map can be obtained by superimposing an instability map on a power dissipation map. Finally, an FEM model was successfully established to simulate the compression test process of this steel. The processing map combined with the FEM model can be very beneficial to solve the problems of residual stress, distortion, and flow instability of components.

  7. 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 studied. (author)

  8. Analytical solution of coupled stress-flow-transport processes in a single rock fracture

    Science.gov (United States)

    Zhao, Zhihong; Jing, Lanru; Neretnieks, Ivars; Moreno, Luis

    2011-09-01

    A closed-form solution is presented for modeling the coupled stress-flow-transport processes along a single fracture embedded in a porous rock matrix. Necessary assumptions were made to simplify the subject into a two-dimensional (2D) problem, considering the changes of fracture aperture and matrix porosity under various stress conditions. The cubic law was assumed to be valid for the fluid flow in the fracture, with an impermeable rock matrix. For transport mechanisms, advective transport along the fracture, longitudinal hydrodynamic dispersion in the flow direction, and the matrix diffusion were considered in three different transport models under constant concentration or constant flux (Danckwerts') inlet boundary conditions. This analytical solution can be used as a constitutive model, or as an example for validation of similar constitutive models, for modeling the coupled hydro-mechanical-chemical (HMC) processes in fracture networks of crystalline rocks. The influences of stress/deformation processes on different transport mechanisms in a single fracture under different inlet boundary conditions were studied for the first time. The results show that changes of fracture, as controlled by a combination of normal closure and shear dilatancy, have a significant influence on the solute concentration distribution both along the fracture and in the rock matrix, as well as on the solute residence/breakthrough time, especially when shear-induced dilatancy occurs. Under compressions, the decreasing matrix porosity slightly increases the solute concentration along the fracture and in the rock matrix.

  9. E-DPSO Algorithm Design and Demonstration about Dynamic Selection and Merging Process of ac-Service Flow

    Directory of Open Access Journals (Sweden)

    Xiaona Xia

    2012-07-01

    Full Text Available Based on the research and development about Web service, the business platform topology of ac-service flow is deepened from architecture-centric perspective. For Web service’s dynamic composition and self-adaptation meeting user requirement, architecture-centric merging among flows is put forward, in order to get this goal, optimizing previous flow granularities’ selection and composition. To satisfy flexible building and mapping of flows, the evolution algorithm E-DPSO based on discrete particle Swarm is designed. With dynamic character of service composition and the integrity of flow sequence, ac-service flow’s implementation strategy is given and finished demonstration. ac-service flow is viewed as the business organization clue, the platform framework structure of service implementation process is built for planning and decision-making.

  10. Automating First-Principles Phase Diagram Calculations

    CERN Document Server

    De van Walle, A

    2002-01-01

    Devising a computational tool that assesses the thermodynamic stability of materials is among the most important steps required to build a ``virtual laboratory'', where materials could be designed from first-principles without relying on experimental input. Although the formalism that allows the calculation of solid state phase diagrams from first principles is well established, its practical implementation remains a tedious process. The development of a fully automated algorithm to perform such calculations serves two purposes. First, it will make this powerful tool available to large number of researchers. Second, it frees the calculation process from arbitrary parameters, guaranteeing that the results obtained are truly derived from the underlying first-principles calculations. The proposed algorithm formalizes the most difficult step of phase diagram calculations, namely the determination of the ``cluster expansion'', which is a compact representation of the configurational dependence of the alloy's energ...

  11. Penguin-like diagrams from the standard model

    Energy Technology Data Exchange (ETDEWEB)

    Ping, Chia Swee [High Impact Research, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2015-04-24

    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 diagram vertex functions are related to one another via Ward-Takahashi identity. From these, a set of relations is obtained connecting the vertex form factors of various penguin diagrams. Explicit expressions for the gluon-photon penguin vertex form factors are obtained, and their contributions to the flavor changing processes estimated.

  12. A Polynomial Invariant Of Twisted Graph Diagrams

    OpenAIRE

    Uhing, Jason

    2007-01-01

    Twisted graph diagrams are virtual graph diagrams with bars on edges. A bijection between abstract graph diagrams and twisted graph diagrams is constructed. Then a polynomial invariant of Yamada-type is developed which provides a lower bound for the virtual crossing number of virtual graph diagrams.

  13. 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

  14. Nash Bargaining on Maximum Flow Time Scheduling with Changeable Processing Time?

    Directory of Open Access Journals (Sweden)

    TANG Guo?chun

    2012-07-01

    Full Text Available In the real world, there often exists the situation where one person is not able to undertake all the jobs alone in a large project. In this paper, we consider the situation where two persons cooperate in the performance of a project. We discuss the (two?person Nash Bargaining problem, where job processing time is a linear function of its start time, each person offers a single machine to process jobs, and his processing cost is defined as his minimized maximum flow time. By proposing a proper division of those jobs, we use the two corresponding subset of jobs, assigned to the two persons respectively, to yield a reasonable cooperative (processing profit allocation scheme acceptable to them.?

  15. Digital image processing of saturation for two-phase flow in planar porous media model

    Directory of Open Access Journals (Sweden)

    Zhi DOU

    2012-06-01

    Full Text Available In this paper, the accuracy of estimating stained non-wetting phase saturation using digital image processing is examined, and a novel post-processing approach for calculating threshold is presented. In order to remove the effect of the background noise of images and to enhance the high-frequency component of the original image, image smoothing and image sharpening methods are introduced. Depending on the correct threshold, the image binarization processing is particularly useful for estimating stained non-wetting phase saturation. Calculated saturation data are compared with the measured saturation data during the two-phase flow experiment in an artificial steel planar porous media model. The results show that the calculated saturation data agree with the measured ones. With the help of an artificial steel planar porous media model, digital image processing is an accurate and simple method for obtaining the stained non-wetting phase saturation.

  16. 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...

  17. Numerical determination of the forming limit diagrams

    OpenAIRE

    T. Pepelnjak; K. Kuzman

    2007-01-01

    Purpose: At present the industrial practice demands a reliable determination of forming limits which assuresthe prediction of properly selecting the forming process in a digital environment. Therefore, technological limitsdefined with the forming limit diagrams (FLDs) have to be known. The experimental evaluation of FLDs forsheet metal is time consuming and demands expensive equipment. The experimental work could be omitted bypredicting the FLD with numerical simulations.Design/methodology/ap...

  18. 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.

  19. Analysis of adaptive forward-backward diffusion flows with applications in image processing

    Science.gov (United States)

    Surya Prasath, V. B.; Urbano, José Miguel; Vorotnikov, Dmitry

    2015-10-01

    The nonlinear diffusion model introduced by Perona and Malik (1990 IEEE Trans. Pattern Anal. Mach. Intell. 12 629-39) is well suited to preserve salient edges while restoring noisy images. This model overcomes well-known edge smearing effects of the heat equation by using a gradient dependent diffusion function. Despite providing better denoizing results, the analysis of the PM scheme is difficult due to the forward-backward nature of the diffusion flow. We study a related adaptive forward-backward diffusion equation which uses a mollified inverse gradient term engrafted in the diffusion term of a general nonlinear parabolic equation. We prove a series of existence, uniqueness and regularity results for viscosity, weak and dissipative solutions for such forward-backward diffusion flows. In particular, we introduce a novel functional framework for wellposedness of flows of total variation type. A set of synthetic and real image processing examples are used to illustrate the properties and advantages of the proposed adaptive forward-backward diffusion flows.

  20. Flow regimes of condensation processes in the emergency condenser test facility. Final report

    International Nuclear Information System (INIS)

    Within the framework of research project 15 NU 09485, 'Calculation and configuration of the passive emergency condenser of an innovative, natural-convection BWR (SWR600) using the ATHLET code', which is closely connected with research project 15 NU 9050, 'Emergency condenser for a medium-output BWR - experiments for performance assessment', measurements were carried out at the NOKO experimental facility for identification of flow regimes and condensation processes. The task was to measure the flow regimes in the NOKO tube by means of needle-type conductuivity probes. The probes were placed into a single heat transfer tube (NOKO single tube) specifically installed for this purpose at the NOKO experimental facility. Several probes were inserted in each of two selected flow sections so that the phase distribution could be measured dynamically during liquid level lowering, i.e. at the probes positioned in downward level direction. The shape of the phase boundaries was reconstructed from the measured data. This arrangement of the probes detects and yields measured data of the various flow regimes occurring. (orig./DG)

  1. 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

  2. Water movement and isoproturon behaviour in a drained heavy clay soil: 1. Preferential flow processes

    Science.gov (United States)

    Haria, A. H.; Johnson, A. C.; Bell, J. P.; Batchelor, C. H.

    1994-12-01

    The processes and mechanisms that control pesticide transport from drained heavy clay catchments are being studied at Wytham Farm (Oxford University) in southern England. In the first field season field-drain water contained high concentrations of pesticide. Soil studies demonstrated that the main mechanism for pesticide translocation was by preferential flow processes, both over the soil surface and through the soil profile via a macropore system that effectively by-passed the soil matrix. This macropore system included worm holes, shrinkage cracks and cracks resulting from ploughing. Rainfall events in early winter rapidly created a layer of saturation in the A horizon perched above a B horizon of very low hydraulic conductivity. Drain flow was initiated when the saturated layer in the A horizon extended into the upper 0.06m of the soil profile; thereafter water moved down slope via horizontal macropores possibly through a band of incorporated straw residues. These horizontal pathways for water movement connected with the fracture system of the mole drains, thus feeding the drains. Overland flow occurred infrequently during the season.

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

    Science.gov (United States)

    Jacobs, T.; Kutzner, C.; Kropp, M.; Brokmann, G.; Lang, W.; Steinke, A.; Kienle, A.; Hauptmann, P.

    2010-10-01

    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.

  4. 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.

  5. Process Development for Hydrothermal Liquefaction of Algae Feedstocks in a Continuous-Flow Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, Douglas C.; Hart, Todd R.; Schmidt, Andrew J.; Neuenschwander, Gary G.; Rotness, Leslie J.; Olarte, Mariefel V.; Zacher, Alan H.; Albrecht, Karl O.; Hallen, Richard T.; Holladay, Johnathan E.

    2013-10-01

    Wet algae slurries can be converted into an upgradeable biocrude by hydrothermal liquefaction (HTL). High levels of carbon conversion to gravity-separable biocrude product were accomplished at relatively low temperature (350 ?C) in a continuous-flow, pressurized (sub-critical liquid water) environment (20 MPa). As opposed to earlier work in batch reactors reported by others, direct oil recovery was achieved without the use of a solvent and biomass trace components were removed by processing steps so that they did not cause process difficulties. High conversions were obtained even with high slurry concentrations of up to 35 wt% of dry solids. Catalytic hydrotreating was effectively applied for hydrodeoxygenation, hydrodenitrogenation, and hydrodesulfurization of the biocrude to form liquid hydrocarbon fuel. Catalytic hydrothermal gasification was effectively applied for HTL byproduct water cleanup and fuel gas production from water soluble organics, allowing the water to be considered for recycle of nutrients to the algae growth ponds. As a result, high conversion of algae to liquid hydrocarbon and gas products was found with low levels of organic contamination in the byproduct water. All three process steps were accomplished in bench-scale, continuous-flow reactor systems such that design data for process scale-up was generated.

  6. Farthest-Polygon Voronoi Diagrams

    CERN Document Server

    Cheong, Otfried; Glisse, Marc; Gudmundsson, Joachim; Hornus, Samuel; Lazard, Sylvain; Lee, Mira; Na, Hyeon-Suk

    2010-01-01

    Given a family of k disjoint connected polygonal sites in general position and of total complexity n, we consider the farthest-site Voronoi diagram of these sites, where the distance to a site is the distance to a closest point on it. We show that the complexity of this diagram is O(n), and give an O(n log^3 n) time algorithm to compute it. We also prove a number of structural properties of this diagram. In particular, a Voronoi region may consist of k-1 connected components, but if one component is bounded, then it is equal to the entire region.

  7. 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)

  8. 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

  9. K-Means Clustering Method to Classify Freeway Traffic Flow Patterns

    Directory of Open Access Journals (Sweden)

    Mehmet Ali Silgu

    2014-06-01

    Full Text Available In this paper, performances of multivariate clustering methods in specifying flow pattern variations reconstructed by a macroscopic flow model are sought. In order to remove the noise in and the wide scatter of traffic data, raw flow measures are filtered prior to modeling process. Traffic flow is simulated by the cell transmission model adopting a two phase fundamental diagram. Flow dynamics specific to the selected freeway test stretch are used to determine prevailing traffic conditions. The classification of flow states over the fundamental diagram are sought utilizing the methods of partitional cluster analyses by considering the stretch density. The fundamental diagram of speed-density is plotted to specify the current corresponding flow state. Non-hierarchical or partitional clustering analysis returned promising results on state classification which in turn helps to capture sudden changes on test stretch flow states. The procedure followed by multivariate clustering methods is systematically dynamic that enables the partitions over the fundamental diagram match approximately with the flow patterns derived by the static partitioning method. The measure of determination coefficient calculated by using the K-means method is comparatively evaluated to statistically derive this conclusion.

  10. 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.

  11. 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, 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.

  12. Twisted diagrams and homotopy sheaves

    CERN Document Server

    Huettemann, Thomas

    2008-01-01

    Twisted diagrams are "diagrams" with components in different categories. Structure maps are defined using auxiliary data which consists of functors relating the various categories to each other. Prime examples of the construction are spectra (in the sense of homotopy theory) and quasi-coherent sheaves on schemes. We develop the basic theory of twisted diagrams, and establish various model structures (which are well-known in special cases). We also introduce a notion of homotopy sheaves, a collection of local data which is compatible up to weak equivalence, and study basic properties of such objects. These objects occur in nature; for example, the notion of an Omega-spectrum fits into this framework. The main purpose of the paper is to provide a convenient reference for model structures on twisted diagrams, and for the language of sheaves and homotopy sheaves as defined here.

  13. The Hertzsprung-Russell Diagram.

    Science.gov (United States)

    Woodrow, Janice

    1991-01-01

    Describes a classroom use of the Hertzsprung-Russell diagram to infer not only the properties of a star but also the star's probable stage in evolution, life span, and age of the cluster in which it is located. (ZWH)

  14. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Oguchi, Masahiro, E-mail: oguchi.masahiro@nies.go.jp; 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. - 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.

  16. 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

  17. Sheaf cohomology in twistor diagrams

    OpenAIRE

    Huggett, S. A.; Penrose, Roger; Roger Penrose

    1980-01-01

    ?One of the earlier achievements of twistor theory was the description of free zero rest mass fields on complexified Minkowski space in terms of holomorphic functions on twistor space. Interactions between these fields are given by certain spacetime integrals (represented by Feynmann diagrams), and some of these integrals have been translated into contour integrals in products of twistor spaces (represented by twistor diagrams). The principal advantage of the twistor diag...

  18. 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.

  19. Decreasing Diagrams and Relative Termination

    CERN Document Server

    Hirokawa, Nao

    2009-01-01

    In this paper we use the decreasing diagrams technique to show that a left-linear term rewrite system R is confluent if all its critical pairs are joinable and the critical pair steps are relatively terminating with respect to R. We further show how to encode the rule-labeling heuristic for decreasing diagrams as a satisfiability problem. Experimental data for both methods are presented.

  20. Bayesian Networks and Influence Diagrams

    DEFF Research Database (Denmark)

    Kjærulff, Uffe Bro; Madsen, Anders Læsø

    2008-01-01

     Probabilistic networks, also known as Bayesian networks and influence diagrams, have become one of the most promising technologies in the area of applied artificial intelligence, offering intuitive, efficient, and reliable methods for diagnosis, prediction, decision making, classification, troubleshooting, and data mining under uncertainty. Bayesian Networks and Influence Diagrams: A Guide to Construction and Analysis provides a comprehensive guide for practitioners who wish to understand, cons...

  1. Phase Diagrams of Forced Magnetic Reconnection in Taylor's Model

    CERN Document Server

    Comisso, L; Waelbroeck, F L

    2015-01-01

    Recent progress in the understanding of how externally driven magnetic reconnection evolves is organized in terms of parameter space diagrams. These diagrams are constructed using four pivotal dimensionless parameters: the Lundquist number $S$, the magnetic Prandtl number $P_m$, the amplitude of the boundary perturbation $\\hat \\Psi_0$, and the perturbation wave number $\\hat k$. This new representation highlights the parameters regions of a given system in which the magnetic reconnection process is expected to be distinguished by a specific evolution. Contrary to previously proposed phase diagrams, the diagrams introduced here take into account the dynamical evolution of the reconnection process and are able to predict slow or fast reconnection regimes for the same values of $S$ and $P_m$, depending on the parameters that characterize the external drive, never considered so far. These features are important to understand the onset and evolution of magnetic reconnection in diverse physical systems

  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. Jerarquización no paramétrica en procesos caracterizados por múltiples indicadores, mediante diagramas de HASSE y conjuntos parcialmente ordenados: Aplicaciones en ingeniería / Non-parametric ranking in multi-indicator processes using HASSE diagrams and partially ordered sets: Enineering applicarions

    Scientific Electronic Library Online (English)

    Claudio M, Rocco S; Elvis, Hernández.

    2013-06-01

    Full Text Available El artículo presenta la aplicación de dos enfoques no paramétricos que permiten jerarquizar procesos a partir de los múltiples indicadores que los caracterizan: el diagrama de Hasse y la teoría de conjuntos parcialmente ordenados. Procesos como la evaluación de un conjunto de proyectos de ingeniería [...] , pueden ser caracterizados por diversos atributos o indicadores que miden aspectos técnicos, financieros, sociales y ambientales, entre otros. A diferencia de otras técnicas que buscan determinar una valor agregado de calidad para cada proceso, mediante el uso de información subjetiva, las técnicas no paramétricas no requieren información adicional y permiten realizar un análisis a priori para: a) evaluar si es posible definir una única jerarquía en forma natural; b) si existen jerarquías en determinados subconjuntos de objetos; o c) si es necesario utilizar algún método que permita realizar la jerarquización únicamente mediante la información de la matriz de múltiples indicadores. Las técnicas seleccionadas se ilustran en tres ejemplos relacionados con el área de la ingeniería. Abstract in english This paper presents the application of two non-parametric approaches allowing the ranking of processes characterized by a multi-indicator matrix: the Hasse diagram and the partial order set theory. Processes like the assessment of engineering projects, are described by a set of technical, financial, [...] social and environmental attributes, among others. While parametric techniques try to determine an aggregate value for each process using subjective information, non-parametric approaches do not require additional information allowing an a priori analysis for: a) assessing if it is possible to define a unique natural ranking; b) determining if there are set of objects that could be partially ranked; or c) applying selected techniques for determine a ranking based only in the information provided by a multi-indicator matrix. The selected approaches are illustrated in three examples, related to engineering problems.

  4. Complex Unsaturated Zone Flow and Thermohydrologic Processes in a Regulatory Environment: A Perspective on Uncertainty

    Science.gov (United States)

    Fedors, R. W.; Manepally, C.; Justus, P. S.; Basagaoglu, H.; Pensado, O.; Dubreuilh, P.

    2007-12-01

    An important part of a risk-informed, performance-based regulatory review of a potential license application for disposal of high-level radioactive waste at Yucca Mountain, Nevada, is the consideration of alternative interpretations and models of risk significant physical processes. The Nuclear Regulatory Commission (NRC) expects that simplified models will be abstracted from complex process-level models to conduct total-system performance assessments. There are several phases or steps to developing an abstracted model and its supporting basis from more detailed and complicated models for each area of the total system. For complex ambient and thermally perturbed flow in fractured tuffs of the unsaturated zone at Yucca Mountain, these steps c,an be summarized as (i) site characterization and observation, (ii) field and laboratory tests, (iii) conceptual model development, (iv) process-level numerical modeling, and (v) abstraction development. Each step is affected by uncertainty in (i) assessing parameters for models and (ii) conceptualization and understanding of governing processes. Because of the complexity and uncertainty, alternative interpretations and models become important aspects in the regulatory environment. NRC staff gain confidence in performance assessment model results through understanding the uncertainty in the various models. An example of a complex process in the unsaturated zone is seepage into drifts, which leads to liquid water potentially contacting waste packages. Seepage is a risk-important process for the unsaturated zone at Yucca Mountain because of its potential effect on waste package integrity and trainsport of potentially released radionuclides. Complexities for seepage include (i) characterization of fractures that carry flow, (ii) effect of small to intermediate scale structural features on flow, (iii) consideration of the diverse flow regimes (rivulets, film flow, capillarity) in fractures, (iv) effect of vapor transport associated with convection along drifts and air flow through fractures, (v) effect of the thermal perturbation caused by radioactive waste, and (vi) consideration of drift stability and climate change because of the long time periods of interest-I 0,000 to a million years. This poster tracks the available information starting from site characterization and continuing on to abstractions used in performance assessment models. At each step, multiple interpretations or alternatives can be identified based on fundamental observations and measurements. From a regulatory perspective, confidence is gained when alternative models or abstractions lead to similar results from a performance assessment; otherwise uncertainty from alternative explanations should be considered in terms of a defendable review. This abstract is an independent product of the CNWRA and does not necessarily reflect the views or regulatory positions of the NRC. The NRC staff views expressed herein are preliminary and do not constitute a final judgment or determination of the matters addressed or of the acceptability of a license application for a geologic repository at Yucca Mountain.

  5. Corrosion barriers processed by Al electroplating and their resistance against flowing Pb-15.7Li

    Science.gov (United States)

    Krauss, Wolfgang; Konys, Jürgen; Wulf, Sven-Erik

    2014-12-01

    In the HCLL blanket design, ferritic-martensitic steels are in direct contact with the flowing liquid breeder Pb-15.7Li and have to withstand severe corrosion attack. Beyond corrosion, T-permeation from the breeder into the RAFM-steels is also an important issue and has to be reduced significantly. Earlier work showed that Al-based coatings can act as barriers for both, however, applied processes e.g. HDA or VPS exhibited strong drawbacks in the past. Meanwhile new industrial relevant coating processes, using electroplating technology are under development and called ECA (electrochemical aluminization) and ECX (electrochemical deposition from ionic liquids) process. In this study electrochemically Al-coated and heat-treated Eurofer samples were tested in PICOLO loop for exposure times up to 12,000 h (ECA) and 2000 h (first results ECX) respectively to determine corrosion properties in flowing Pb-15.7Li (550 °C, 0.1 m/s). Cross section analysis afterward corrosion testing proved the ability of thin Al-based barriers made by electrochemical techniques to protect the bare Eurofer from corrosion attack even at exposure times of 12,000 h. Determined radial corrosion rates lay between 10 and 20 ?m/a. First results for ECX coated samples (2000 h) revealed more homogeneous corrosion behavior of the barrier layer itself compared to ECA.

  6. Corrosion barriers processed by Al electroplating and their resistance against flowing Pb–15.7Li

    Energy Technology Data Exchange (ETDEWEB)

    Krauss, Wolfgang, E-mail: wolfgang.krauss@kit.edu; Konys, Jürgen; Wulf, Sven-Erik

    2014-12-15

    In the HCLL blanket design, ferritic–martensitic steels are in direct contact with the flowing liquid breeder Pb–15.7Li and have to withstand severe corrosion attack. Beyond corrosion, T-permeation from the breeder into the RAFM-steels is also an important issue and has to be reduced significantly. Earlier work showed that Al-based coatings can act as barriers for both, however, applied processes e.g. HDA or VPS exhibited strong drawbacks in the past. Meanwhile new industrial relevant coating processes, using electroplating technology are under development and called ECA (electrochemical aluminization) and ECX (electrochemical deposition from ionic liquids) process. In this study electrochemically Al-coated and heat-treated Eurofer samples were tested in PICOLO loop for exposure times up to 12,000 h (ECA) and 2000 h (first results ECX) respectively to determine corrosion properties in flowing Pb–15.7Li (550 °C, 0.1 m/s). Cross section analysis afterward corrosion testing proved the ability of thin Al-based barriers made by electrochemical techniques to protect the bare Eurofer from corrosion attack even at exposure times of 12,000 h. Determined radial corrosion rates lay between 10 and 20 ?m/a. First results for ECX coated samples (2000 h) revealed more homogeneous corrosion behavior of the barrier layer itself compared to ECA.

  7. Corrosion barriers processed by Al electroplating and their resistance against flowing Pb–15.7Li

    International Nuclear Information System (INIS)

    In the HCLL blanket design, ferritic–martensitic steels are in direct contact with the flowing liquid breeder Pb–15.7Li and have to withstand severe corrosion attack. Beyond corrosion, T-permeation from the breeder into the RAFM-steels is also an important issue and has to be reduced significantly. Earlier work showed that Al-based coatings can act as barriers for both, however, applied processes e.g. HDA or VPS exhibited strong drawbacks in the past. Meanwhile new industrial relevant coating processes, using electroplating technology are under development and called ECA (electrochemical aluminization) and ECX (electrochemical deposition from ionic liquids) process. In this study electrochemically Al-coated and heat-treated Eurofer samples were tested in PICOLO loop for exposure times up to 12,000 h (ECA) and 2000 h (first results ECX) respectively to determine corrosion properties in flowing Pb–15.7Li (550 °C, 0.1 m/s). Cross section analysis afterward corrosion testing proved the ability of thin Al-based barriers made by electrochemical techniques to protect the bare Eurofer from corrosion attack even at exposure times of 12,000 h. Determined radial corrosion rates lay between 10 and 20 ?m/a. First results for ECX coated samples (2000 h) revealed more homogeneous corrosion behavior of the barrier layer itself compared to ECA

  8. 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

  9. 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.

  10. 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

  11. Gas Hydrate Stability and Sampling: The Future as Related to the Phase Diagram

    OpenAIRE

    E. Dendy Sloan; Amadeu K. Sum; Carolyn A. Koh

    2010-01-01

    The phase diagram for methane + water is explained, in relation to hydrate applications, such as in flow assurance and in nature. For natural applications, the phase diagram determines the regions for hydrate formation for two- and three-phase conditions. Impacts are presented for sample preparation and recovery. We discuss an international study for “Round Robin” hydrate sample preparation protocols and testing.

  12. Integrated process design for the inter-company plant layout planning of dynamic mass flow networks. PepOn

    OpenAIRE

    Geldermann, Jutta; Treitz, Martin; Schollenberger, Hannes; Ludwig, Jens; Rentz, Otto [Hrsg.

    2007-01-01

    Inter-company production networks can improve the resource efficiency of production processes. This book shows the results of the research project ?Integrated Process Design for the Inter-Company Plant Layout Planning of Dynamic Mass Flow Networks? (PepOn). A systematic approach for process design for the best utilisation of process streams based on multiple pinch analyses is proposed for a holistic evaluation of process alternatives and for determining saving potentials for production networ...

  13. Modelling soil heat and water flow as a coupled process in land surface models

    OpenAIRE

    Garcia-Gonzalez, R.; Verhoef, A.; Vidale, P.L.; Braud, I.

    2010-01-01

    To improve model estimates of soil water and heat flow by land surface models (LSMs), in particular in the first few centimetres of the near-surface soil profile, we have to consider in detail all the relevant physical processes involved (see e.g. Milly, 1982). Often, thermal and iso-thermal vapour fluxes in LSMs are neglected and the simplified Richard's equation is used as a result. Vapour transfer may affect the water fluxes and heat transfer in LSMs used for hydrometeorological and cli...

  14. 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

  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 po...

  16. Neutron monitors for monitoring process and waste flow in a reprocessing plant

    International Nuclear Information System (INIS)

    The detection of neutrons offers the possibility of determining the plutonium and monitoring the criticality directly at the part of the plant concerned. The state of neutron monitor development and the basic possibilities of application for process and safety monitoring are shown. Requirements for the equipment and necessary quality assurance measures are discussed with examples. Examples are explained for passive neutron measurement (Pu cleaning cycles, Pu loading of refined material flow) and for the active measurement of neutrons using a steady neutron source (Pu and Cm/Pu on fuel element cans, criticality for vibration of rods, fuel element monitors etc.). (orig./RB)

  17. Parallel pulse processing and data acquisition for high speed, low error flow cytometry

    Science.gov (United States)

    van den Engh, Gerrit J. (Livermore, CA); Stokdijk, Willem (Livermore, CA)

    1992-01-01

    A digitally synchronized parallel pulse processing and data acquisition system for a flow cytometer has multiple parallel input channels with independent pulse digitization and FIFO storage buffer. A trigger circuit controls the pulse digitization on all channels. After an event has been stored in each FIFO, a bus controller moves the oldest entry from each FIFO buffer onto a common data bus. The trigger circuit generates an ID number for each FIFO entry, which is checked by an error detection circuit. The system has high speed and low error rate.

  18. An Approach to Code Generation from UML Diagrams

    OpenAIRE

    Harshal D. Gurad; V. S. Mahalle2

    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...

  19. 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.

  20. Database design using entity-relationship diagrams

    CERN Document Server

    Bagui, Sikha

    2011-01-01

    Data, Databases, and the Software Engineering ProcessDataBuilding a DatabaseWhat is the Software Engineering Process?Entity Relationship Diagrams and the Software Engineering Life Cycle          Phase 1: Get the Requirements for the Database          Phase 2: Specify the Database          Phase 3: Design the DatabaseData and Data ModelsFiles, Records, and Data ItemsMoving from 3 × 5 Cards to ComputersDatabase Models     The Hierarchical ModelThe Network ModelThe Relational ModelThe Relational Model and Functional DependenciesFundamental Relational DatabaseRelational Database and SetsFunctional

  1. Simulation of Coupled Processes of Flow, Transport, and Storage of CO2 in Saline Aquifers

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Yu-Shu; Chen, Zizhong; Kazemi, Hossein; Yin, Xiaolong; Pruess, Karsten; Oldenburg, Curt; Winterfeld, Philip; Zhang, Ronglei

    2014-09-30

    This report is the final scientific one for the award DE- FE0000988 entitled “Simulation of Coupled Processes of Flow, Transport, and Storage of CO2 in Saline Aquifers.” The work has been divided into six tasks. In task, “Development of a Three-Phase Non-Isothermal CO2 Flow Module,” we developed a fluid property module for brine-CO2 mixtures designed to handle all possible phase combinations of aqueous phase, sub-critical liquid and gaseous CO2, supercritical CO2, and solid salt. The thermodynamic and thermophysical properties of brine-CO2 mixtures (density, viscosity, and specific enthalpy of fluid phases; partitioning of mass components among the different phases) use the same correlations as an earlier fluid property module that does not distinguish between gaseous and liquid CO2-rich phases. We verified the fluid property module using two leakage scenarios, one that involves CO2 migration up a blind fault and subsequent accumulation in a secondary “parasitic” reservoir at shallower depth, and another investigating leakage of CO2 from a deep storage reservoir along a vertical fault zone. In task, “Development of a Rock Mechanical Module,” we developed a massively parallel reservoir simulator for modeling THM processes in porous media brine aquifers. We derived, from the fundamental equations describing deformation of porous elastic media, a momentum conservation equation relating mean stress, pressure, and temperature, and incorporated it alongside the mass and energy conservation equations from the TOUGH2 formulation, the starting point for the simulator. In addition, rock properties, namely permeability and porosity, are functions of effective stress and other variables that are obtained from the literature. We verified the simulator formulation and numerical implementation using analytical solutions and example problems from the literature. For the former, we matched a one-dimensional consolidation problem and a two-dimensional simulation of the Mandel-Cryer effect. For the latter, we obtained a good match of temperature and gas saturation profiles, and surface uplift, after injection of hot fluid into a model of a caldera structure. In task, “Incorporation of Geochemical Reactions of Selected Important Species,” we developed a novel mathematical model of THMC processes in porous and fractured saline aquifers, simulating geo-chemical reactions associated with CO2 sequestration in saline aquifers. Two computational frameworks, sequentially coupled and fully coupled, were used to simulate the reactions and transport. We verified capabilities of the THMC model to treat complex THMC processes during CO2 sequestration by analytical solutions and we constructed reactive transport models to analyze the THMC process quantitatively. Three of these are 1D reactive transport under chemical equilibrium, a batch reaction model with equilibrium chemical reactions, and a THMC model with CO2 dissolution. In task “Study of Instability in CO2 Dissolution-Diffusion-Convection Processes,” We reviewed literature related to the study of density driven convective flows and on the instability of CO2 dissolution-diffusion-convection processes. We ran simulations that model the density-driven flow instability that would occur during CO2 sequestration. CO2 diffused through the top of the system and dissolved in the aqueous phase there, increasing its density. Density fingers formed along the top boundary, and coalesced into a few prominent ones, causing convective flow that forced the fluid to the system bottom. These simulations were in two and three dimensions. We ran additional simulations of convective mixing with density contrast caused by variable dissolved CO2 concentration in saline water, modeled after laboratory experiments in which supercritical CO2 was circulated in the headspace above a brine saturated packed sand in a pressure vessel. As CO2 dissolved into the upper part of the saturated sand, liquid phase density increases causing instability and setting off convective mixing. We obtained good agreement

  2. 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.

    Full Text Available 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.

  3. Sequential process of atomic layer epitaxy under the conditions of gas flow and high vacuum

    International Nuclear Information System (INIS)

    Essential features of atomic layer epitaxy (ALE) are reviewed with particular attention being paid to the growth of monocrystalline films under gas flow conditions. The sequential supply of chemical reactants (so-called precursors) - separated by purging phases - causes the basic effect: an introduced precursor finds a reaction partner exclusively in the adsorption layer. Consequently, the process can be considered as deposition (or epitaxy if monocrystalline film is obtained) from adsorption layers. The kind of surrounding medium plays a secondary role by delivering the precursors and removing the reaction by-products. Owing the surface tension in the adsorbed layers, the produced solid films are smoother than those obtained by alternative procedures. ALE may be achieved in the gas flow system (ALE-GF), as well as a mode of molecular beam epitaxy (ALE-MBE). The differences for applications between the two result from molecular and continuum flows - shadowing is easier in the high vacuum, while the gas environment gives better possibilities to produce continuous films of uniform thickness in grooves or in irregularly shaped substrates

  4. Finite Element Simulation of Dynamic Wetting Flows as an Interface Formation Process

    CERN Document Server

    Sprittles, James

    2012-01-01

    A mathematically challenging model of dynamic wetting as a process of interface formation has been, for the first time, fully incorporated into a numerical code based on the finite element method and applied, as a test case, to the problem of capillary rise. The motivation for this work comes from the fact that, as discovered experimentally more than a decade ago, the key variable in dynamic wetting flows -the dynamic contact angle - depends not just on the velocity of the three-phase contact line but on the entire flow field/geometry. Hence, to describe this effect, it becomes necessary to use the mathematical model that has this dependence as its integral part. A new physical effect, termed the `hydrodynamic resist to dynamic wetting', is discovered where the influence of the capillary's radius on the dynamic contact angle, and hence on the global flow, is computed. The capabilities of the numerical framework are then demonstrated by comparing the results to experiments on the unsteady capillary rise, where...

  5. 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...

  6. A mesoscopic formalism for simulating particle-laden flows with applications in energy conversion processes

    Science.gov (United States)

    Capecelatro, Jesse Samuel

    The non-linear and multiscale nature of turbulent flows is further complicated in the presence of inertial particles. Intimate coupling between the phases may lead to a high degree of spatial segregation that reorganizes the structure of the underlying turbulence. The wide range of relevant length and timescales associated with fluid-particle systems poses significant challenges in understanding and predicting their behavior. In recent years, the advent of petascale computing has enabled the direct numerical simulation (DNS) of large-scale turbulent flows, though DNS of particle-laden flows remains severely limited. This work presents methods to alleviate previous numerical constraints on the computational grid when considering finite-size particles. Volume filtered equations for the carrier phase are derived in detail for variable-density flows in the presence of particles and solved in a highly-scalable Eulerian-Lagrangian framework. The filter introduces a separation in length-scales during the interphase exchange process, where everything smaller than the support of the filtering kernel requires modeling (e.g., surface reactions and drag), and everything larger than the support of the filtering kernel is captured explicitly. To remain computationally tractable, the filtering procedure is solved in two steps, by first transferring the particle information to the nearest neighboring cells, and then making use of an implicit diffusion operation. In ows that exhibit strong spatial segregation in particle concentration, a separation of length scales must be established when extracting Lagrangian statistics. To accomplish this, an adaptive spatial filter is employed on the particle data with an averaging volume that varies with the local particle-phase volume fraction. The filtered Euler-Lagrange formalism is shown to yield highly accurate and physical results for large-scale particle-laden ows from the dilute to dense regime. An analysis of chemically reacting species in circulating uidized bed risers reveals that the non-homogeneities caused by the formation of clusters significantly reduces the efficiency of the conversion process. To better understand the fundamental nature of particle clustering and its effects on the carrier-phase turbulence, a canonical ow is introduced, referred to as cluster-induced turbulence (CIT). Simulations of fully-developed, gravity-driven CIT are investigated, revealing for the first time the local instantaneous distribution of particle-phase dynamics in collisional gas-solid flows.

  7. 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

  8. 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.

  9. 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)

  10. Particle methods for simulation of subsurface multiphase fluid flow and biogeological processes

    International Nuclear Information System (INIS)

    A number of particle models that are suitable for simulating multiphase fluid flow and biogeological 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.

  11. Groundwater flow processes and mixing in active volcanic systems: the case of Guadalajara (Mexico)

    Science.gov (United States)

    Hernández-Antonio, A.; Mahlknecht, J.; Tamez-Meléndez, C.; Ramos-Leal, J.; Ramírez-Orozco, A.; Parra, R.; Ornelas-Soto, N.; Eastoe, C. J.

    2015-09-01

    Groundwater chemistry and isotopic data from 40 production wells in the Atemajac and Toluquilla valleys, located in and around the Guadalajara metropolitan area, were determined to develop a conceptual model of groundwater flow processes and mixing. Stable water isotopes (?2H, ?18O) were used to trace hydrological processes and tritium (3H) to evaluate the relative contribution of modern water in samples. Multivariate analysis including cluster analysis and principal component analysis were used to elucidate distribution patterns of constituents and factors controlling groundwater chemistry. Based on this analysis, groundwater was classified into four groups: cold groundwater, hydrothermal groundwater, polluted groundwater and mixed groundwater. Cold groundwater is characterized by low temperature, salinity, and Cl and Na concentrations and is predominantly of Na-HCO3-type. It originates as recharge at "La Primavera" caldera and is found predominantly in wells in the upper Atemajac Valley. Hydrothermal groundwater is characterized by high salinity, temperature, Cl, Na and HCO3, and the presence of minor elements such as Li, Mn and F. It is a mixed-HCO3 type found in wells from Toluquilla Valley and represents regional flow circulation through basaltic and andesitic rocks. Polluted groundwater is characterized by elevated nitrate and sulfate concentrations and is usually derived from urban water cycling and subordinately from agricultural return flow. Mixed groundwaters between cold and hydrothermal components are predominantly found in the lower Atemajac Valley. Twenty-seven groundwater samples contain at least a small fraction of modern water. The application of a multivariate mixing model allowed the mixing proportions of hydrothermal fluids, polluted waters and cold groundwater in sampled water to be evaluated. This study will help local water authorities to identify and dimension groundwater contamination, and act accordingly. It may be broadly applicable to other active volcanic systems on Earth.

  12. Hysteresis processes in the regular reflection?Mach reflection transition in steady flows

    Science.gov (United States)

    Ben-Dor, G.; Ivanov, M.; Vasilev, E. I.; Elperin, T.

    2002-05-01

    Ernst Mach recorded experimentally, in the late 1870s, two different shock-wave reflection configurations and laid the foundations for one of the most exciting and active research field in an area that is generally known as Shock Wave Reflection Phenomena. The first wave reflection, a two-shock wave configuration, is known nowadays as regular reflection, RR, and the second wave reflection, a three-shock wave configuration, was named after Ernst Mach and is called nowadays Mach reflection, MR. A monograph entitled Shock Wave Reflection Phenomena, which was published by Ben-Dor in 1990, summarized the state-of-the-art of the reflection phenomena of shock waves in steady, pseudo-steady and unsteady flows. Intensive analytical, experimental and numerical investigations in the last decade, which were led mainly by Ben-Dor's research group and his collaboration with Chpoun's, Zeitoun's and Ivanov's research groups, shattered the state-of-the-knowledge, as it was presented in Ben-Dor (Shock Wave Reflection Phenomena, Springer, New York, 1991), for the case of steady flows. Skews's and Hornung's research groups joined in later and also contributed to the establishment of the new state-of-the-knowledge of the reflection of shock waves in steady flows. The new state-of-the-knowledge will be presented in this review. Specifically, the hysteresis phenomenon in the RR?MR transition process, which until the early 1990s was believed not to exist, will be presented and described in detail, in a variety of experimental set-ups and geometries. Analytical, experimental and numerical investigations of the various hysteresis processes will be presented.

  13. Unsaturated and Saturated Flow Front Tracking in Liquid Composite Molding Processes using Dielectric Sensors

    Science.gov (United States)

    Carlone, P.; Palazzo, G. S.

    2015-10-01

    Liquid composite molding processes are manufacturing techniques involving the impregnation and saturation of dry fibrous preforms by means of injection or infusion of catalyzed resin systems. Complete wetting of the reinforcement and reduction of voids are key issues to enhance mechanical properties of the final product, as a consequence on line monitoring and control of resin flow is highly desirable to detect and avoid potentialbet macro- as well as micro-voids. In this paper, parallel-plate dielectric sensors were investigated to track the position of unsaturated as well as saturated flow fronts through dual scale porous media. Sensors configuration was analyzed and improved via electromagnetic (EM) finite element simulations. The effectiveness of the proposed system was assessed in one-dimensional impregnation tests. Good agreement was found between unsaturated front positions provided by the considered system and acquired through conventional visual techniques. An indirect verification strategy, based on CFD and EM simulations of the process, was applied to investigate the reliability of dielectric sensors with respect to saturation phenomena. Obtained outcomes highlighted the intriguing capabilities of the proposed method.

  14. Deterministic flows of order-parameters in stochastic processes of quantum Monte Carlo method

    International Nuclear Information System (INIS)

    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(= ?)-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. Ultrafast Excitonic and Plasmonic Processes at the Nanoscale: Understanding Energy Flow in Hybrid Nanostructures

    Science.gov (United States)

    Wiederrecht, Gary

    2015-03-01

    Nanoscale plasmonic and excitonic structures frequently possess ultrafast processes that can be initiated and monitored by light. Nanoscale structures lend themselves to strong light-matter interactions for a variety of reasons, including a tendency towards large optical extinction and polarizability. Many times these nanostructures have strong resonances due to collective excitations with coherence, a property that lends itself very well to optical control opportunities. These types of collective excitations can also couple strongly to excitations of other nanostructures with different composition and with disparate properties in order to realize hybrid excitations. Hybridization presents unique opportunities for inducing directional energy and charge flow initiated by light. Thus, using ultrafast pulses of appropriate photon energy, combined with considerations of material composition and shape, brings the possibility to control energy flow in excitonic and plasmonic hybrid nanostructures. In this talk, I discuss our recent efforts to create and characterize electronically coupled nanostructures and the impact this has on ultrafast photoresponse. These processes have strong impact on applications such as light harvesting and nonlinear optical responses in nanoscale structures. Use of the Center for Nanoscale Materials was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-06CH11357.

  16. 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.

  17. Assessment of Controlling Processes for Field-Scale Uranium Reactive Transport under Highly Transient Flow Conditions

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-02-13

    This paper presents the results of a comprehensive model-based analysis of a uranium tracer test conducted at the U.S Department of Energy Hanford 300 Area (300A) IFRC site. A three-dimensional multi-component reactive transport model was employed to assess the key factors and processes that control the field-scale uranium reactive transport. Taking into consideration of relevant physical and chemical processes, the selected conceptual/numerical model replicates the spatial and temporal variations of the observed U(VI) concentrations reasonably well in spite of the highly complex field conditions. A sensitivity analysis was performed to interrogate the relative importance of various processes and factors for reactive transport of U(VI) at the field-scale. The results indicate that multi-rate U(VI) sorption/desorption, U(VI) surface complexation reactions, and initial U(VI) concentrations 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, which were previously identified to be important in laboratory experiments, played less important roles under the field-scale experimental condition at the 300A site. However, the model simulations also revealed that the groundwater chemistry was relatively stable during the uranium tracer experiment and therefore presumably not dynamic enough to appropriately assess the effects of ion exchange reaction and the choice of surface complexation models on U(VI) sorption and desorption. Furthermore, it also showed that the field experimental duration (16 days) was not sufficiently long to precisely assess the role of a majority of the sorption sites that were accessed by slow kinetic processes within the dual domain model. The sensitivity analysis revealed the crucial role of the intraborehole flow that occurred within the long-screened monitoring wells and thus significantly affected both field-scale measurements and simulated U(VI) concentrations as a combined effect of aquifer heterogeneity and highly dynamic flow conditions. Overall, this study, which provides one of the few detailed and highly data-constrained uranium transport simulations, highlights the difference in controlling processes between laboratory and field scale that prevent a simple direct upscaling of laboratory-scale models.

  18. Preliminary economic evaluation of the Alkox process

    International Nuclear Information System (INIS)

    A new chemical process has been invented at Battelle Pacific Northwest Laboratories for converting alkanes to alcohols. This new chemistry has been named the ''Alkox Process.'' Pacific Northwest Laboratory prepared a preliminary economic analysis for converting cyclohexane to cyclohexanol, which may be one of the most attractive applications of the Alkox process. A process flow scheme and a material balance were prepared to support rough equipment sizing and costing. The results from the economic analysis are presented in the non-proprietary section of this report. The process details, including the flow diagram and material balance, are contained in separate section of this report that is proprietary to Battelle. 7 refs., 4 tabs

  19. 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.

  20. Process development of Chemical etching and Diffusion Bonding for Helium Flow Channel

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Y. J.; Kim, B. Y.; Kim, J. P.; Sohn, Y. E. [Innoworld Co., Seoul (Korea, Republic of)

    2010-04-15

    This research aimed at developing a wet chemical etching technique to machine the He flow channel of the process heat exchanger(PHE) made of Hastelloy X or equivalent high temperature high corrosion resistance material such as Alloy 617 and establishing an optimum diffusion bonding condition of these materials to assemble the PHE. The project is dealt with finding an optimum chemical etchant to develop about 0.5mm depth and 1.0 mm width on the surface of about 1.5mm thick Hastelloy-X sheet materials(or equivalents) and an process parameters for the diffusion bonding of the Hastelloy-X plates. Moderate performance results of etching process for high corrosion resistance material such as Alloy 617 was obtained. Namely, We could get the optimum chemical etchant to develop about 0.1{approx}0.2mm depth and 1.0 mm width on the surface of about 1.5mm thick sheet materials. We could get a process parameters for the diffusion bonding of the Hastelloy X plates. Tensile strength test for diffusion bonded sample was performed and above eighty percent of original material strength was obtained

  1. Improving modeling with layered UML diagrams

    DEFF Research Database (Denmark)

    Störrle, Harald

    2013-01-01

    Layered diagrams are diagrams whose elements are organized into sets of layers. Layered diagrams are routinely used in many branches of engineering, except Software Engineering. In this paper, we propose to add layered diagrams to UML modeling tools, and elaborate the concept by exploring usage scenarios. We validate the concept by implementation, lab assessments, and field testing. We conclude that layers enhance and complement conventional diagrams and model structuring techniques, are easy to...

  2. The Lexis diagram, a misnomer

    Directory of Open Access Journals (Sweden)

    2001-03-01

    Full Text Available Around 1870, demographers felt the need for a simple chart to present population dynamics. This chart is known as the Lexis diagram, but it is a misnomer. To be useful, this chart must allow for the systematic location on one plane of the three classical demographic co-ordinates, namely: the date, the age and the moment of birth. There are three solutions for this problem. In 1869, Zeuner worked out a first solution. In 1870, Brasche proposed a second one with networks of parallels; it is the version most currently used now. In 1874, Becker proposed the third one. In 1875, certainly after Verwey, Lexis took back the Zeuner's diagram and just added networks of parallels. In spite of all this, the name "Lexis diagram" has imposed itself in a seemingly invincible way.

  3. 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.

  4. Variation of gas flow speed on the UO2 kernel coating process with computational fluid dynamic (CFD)

    International Nuclear Information System (INIS)

    Coating of UO2 kernel is one of the many step in nuclear fuel preparation which is very urgent to find the best product of high temperature processes produced pyrocarbon and silica carbide coated using chemical vapor deposition process. The main aspect observed in fluidization is fluid mechanic which describes what has happened in fluidization process. The ability to predict early fluidization is very important in fluidization process. It was done to find the best product of process, high life time, determining minimum and maximum flow rate of fluidization. Liquid or gas when they are going through from below to the top of solid the particle at minimum flow rate, particle will not move, if the flow rate of a liquid or gas is increased, particle will move. This flow rate is called minimum fluidization flow rate. In fluidization, when flow rate which is gone through particles is increased, so the pressure difference in reactors will increase. All particles will move and acts like a fluid. This condition is fluidized bed. A chemical reaction occurs in fluidization will also influence on process condition and mass transfer also occurs during the fluidization process. In this research, pyrocarbon and silica carbide process modeling was done by use of Computational Fluid Dynamic, Fluent 6.3, and before that, sketching reactor with Gambit 2.2.30, was carried out and then was done by Fluent 6.3 software. Fluidization process was calculated by Eulerian multiphase and gas was as primer phase and particle was as secondary phase. The model was chosen for unsteady state and laminar. The Syamal-Obrien theory was done for interaction phase calculation. It was found that the gas flow rate was 8 m/sec, kernels still go down, it was compatible with calculation minimum fluidization flow rate 8.6 m/sec. Comparatively with experiment data of glass reactor it was found that flow rate 9.6 m/sec good fluidization meanwhile fluidization with a flow rate 7.4 m/sec kernels go down. Calculation data will be used for operation of reactor fluidization of nuclear fuel coating research in PTAPB-BATAN Yogyakarta. (author)

  5. Flow processes in overexpanded chemical rocket nozzles. Part 3: Methods for the aimed flow separation and side load reduction

    Science.gov (United States)

    Schmucker, R. H.

    1983-01-01

    Methods aimed at reduction of overexpansion and side load resulting from asymmetric flow separation for rocket nozzles with a high opening ratio are described. The methods employ additional measures for nozzles with a fixed opening ratio. The flow separation can be controlled by several types of nozzle inserts, the properties of which are discussed. Side loads and overexpansion can be reduced by adapting the shape of the nozzle and taking other additional measures for controlled separation of the boundary layer, such as trip wires.

  6. 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

  7. 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.

  8. Numerical modeling of flow processes inside geothermal wells: An approach for predicting production characteristics with uncertainties

    International Nuclear Information System (INIS)

    One dimensional steady and transient numerical modeling for describing the heat and fluid dynamic transport inside geothermal wells has been conducted. The mass, momentum and energy governing equations were solved using a segregated numerical scheme. Discretized governing equations for the fluid flow were coupled and solved with a fully implicit step by step method. The mathematical formulation used suitable empirical correlations for estimating the convective heat transfer coefficients as well as the shear stress and the void fraction parameters. Heat conduction across the wellbore materials was solved by an implicit central difference numerical scheme using the tri-diagonal matrix algorithm (TDMA). The flow characteristics of producer geothermal wells (pressure, temperature, enthalpy, heat fluxes, etc.) at each depth node were computed. Analytical data reported in the literature were used to validate the numerical capability of the wellbore simulator developed for this study (GEOWELLS). This simulator, together with another computer code (ORKISZEWSKI), was applied for modeling the heat and fluid flow processes inside some wells drilled in Mexican geothermal fields. The simulated pressure and temperature profiles were statistically compared against stable measured field data (through the computation of the residual sum of squares and Chi-square). A good agreement between the simulated and measured profiles of pressure and temperature was consistently obtained, having the best matching results for the GEOWELLS predictions. An analysis of the sensitivity and uncertainty was finally conducted to estimate the confidence to be accorded the simulation results predicted by GEOWELLS. Matching the sensitivity to variations in some input parameters (e.g., pressure, temperature, enthalpy and void fraction) was examined. The void fraction was identified as one of the most important parameters that affect the GEOWELLS simulations for matching measured field data correctly

  9. Kinematical Diagrams for Conical Relativistic Jets

    Indian Academy of Sciences (India)

    Gopal-Krishna; Pronoy Sircar; Samir Dhurde

    2007-03-01

    We present diagrams depicting the expected inter-dependences of two key kinematical parameters of radio knots in the parsec-scale jets of blazars, deduced from VLBI observations. The two parameters are the apparent speed (app = capp) and the effective Doppler boosting factor (eff) of the relativistically moving radio knot. A novel aspect of these analytical computations of – diagrams is that they are made for parsecscale jets having a conical shape, with modest opening angles ( up to 10°), in accord with the VLBI observations of the nuclei of the nearest radio galaxies. Another motivating factor is the recent finding that consideration of a conical geometry can have important implications for the interpretation of a variety of radio observations of blazar jets. In addition to uniform jet flows (i.e., those having a uniform bulk Lorentz factor, ), computational results are also presented for stratified jets where an ultra-relativistic central spine along the jet axis is surrounded by a slower moving sheath, possibly arising from a velocity shear.

  10. 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

  11. 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.

  12. Continuous-flow C. elegans fluorescence expression analysis with real-time image processing through microfluidics.

    Science.gov (United States)

    Yan, Yuanjun; Boey, Daryl; Ng, Li Theng; Gruber, Jan; Bettiol, Andrew; Thakor, Nitish V; Chen, Chia-Hung

    2016-03-15

    The nematode Caenorhabditis elegans has become an essential model organism in neuroscience research because of its stereotyped anatomy, relevance to human biology, and capacity for genetic manipulation. To solve the intrinsic challenges associated with performing manual operations on C. elegans, many automated chip designs based on immobilization-imaging-release approaches have been proposed. These designs are prone to limitations such as the exertion of physical stress on the worms and limited throughput. In this work, a continuous-flow, high-throughput, automated C. elegans analyzer based on droplet encapsulation and real-time image processing was developed to analyze fluorescence expression in worms. To demonstrate its capabilities, two strains of C. elegans nematodes with different levels of expression of green fluorescent protein (GFP) were first mixed in a buffer solution. The worms were encapsulated in water-in-oil droplets to restrict random locomotion. The droplets were closely packed in a two-layer polydimethylsiloxane (PDMS) platform and were flowed through a narrow straight channel, in which a region of interest (ROI) was defined and continuously recorded by a frame acquisition device. Based on the number of pixels counted in the selected color range, our custom software analyzed GFP expression to differentiate between two strains with nearly 100% accuracy and a throughput of 0.5seconds/worm. PMID:26452079

  13. 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

  14. Process options and projected mass flows for the HTGR refabrication scrap recovery system

    International Nuclear Information System (INIS)

    The two major uranium recovery processing options reviewed are (1) internal recovery of the scrap by the refabrication system and (2) transfer to and external recovery of the scrap by the head end of the reprocessing system. Each option was reviewed with respect to equipment requirements, preparatory processing, and material accountability. Because there may be a high cost factor on transfer of scrap fuel material to the reprocessing system for recovery, all of the scrap streams will be recycled internally within the refabrication system, with the exception of reject fuel elements, which will be transferred to the head end of the reprocessing system for uranium recovery. The refabrication facility will be fully remote; thus, simple recovery techniques were selected as the reference processes for scrap recovery. Crushing, burning, and leaching methods will be used to recover uranium from the HTGR refabrication scrap fuel forms, which include particles without silicon carbide coatings, particles with silicon carbide coatings, uncarbonized fuel rods, carbon furnace parts, perchloroethylene distillation bottoms, and analytical sample remnants. Mass flows through the reference scrap recovery system were calculated for the HTGR reference recycle facility operating with the highly enriched uranium fuel cycle. Output per day from the refabrication scrap recovery system is estimated to be 4.02 kg of 2355U and 10.85 kg of 233U. Maximum equipment capacities were determined, and future work will be directed toward the development and costing of the scrap recovery system chosen as reference

  15. Development of pyrometallurgical partitioning technology of transuranium elements with process flow sheet

    International Nuclear Information System (INIS)

    The dry process for partitioning of transuranium elements from high level liquid waste has been developed, based on the concept with burning TRUs coming from the light water reactor cycle in a metallic fuel FBR. The experimental results on each process of dry method, i.e. denitration, chlorination, pyrometallurgical partitioning with reductive extraction and electrorefining, and waste salt treatment are summarized. It was assured that HLW can be transformed to chlorides through oxide conversion with high efficiency by the experiments with simulated wastes. For reductive extraction and electrorefining, oxidation-reduction potential, activity coefficients, distribution coefficients and separation factor between TRUs and rare earths in a system with molten chlorides-liquid cadmium ior bismuth were measured, and it was feasible to remove TRUs more than 99% from the salt. Moreover, it was found that the high separation ratio between TRUs and rare earths was obtained by counter current reduction extraction using cadmium or bismuth. The method to transform waste chlorides into stable oxides and to make the waste glass was developed. Based on the results, the process flow sheet with material balance to recover TRUs from HLW is proposed. (author) 69 refs

  16. Stabilized methods and post-processing techniques for Darcy flow and related problems

    International Nuclear Information System (INIS)

    In this paper we present a review of stabilized methods and post-processing techniques for Darcy flow problems, with particular emphasis in the miscible displacement model. The system of partial differential equations governing the miscible displacement consists of an elliptic system coming from the conservation of mass and Darcy's law and a nonlinear transport equation expressing the conservation of the injected fluid (concentration). The main difficulties are related to the evaluation of the primary unknowns of the elliptic equation (pressure) and their spatial derivatives by Darcy's law (velocity) and the coupling with the convection dominated transport equation. Finite element solutions for this problem have been obtained using mixed methods for the pressure/gradient problem combined with the modified method of characteristics. However, this approach involves different interpolation schemes for pressure, velocity and concentration. In order to overcome the difficulties associated with the previous schemes, we have been working in the development of finite element formulations where all variables are interpolated by equal-order functions. To recover accurate velocity approximations we have developed new global and local post-processing techniques. These post-processing techniques consist in solving the elliptic problem for pressure and then computing velocity considering residual forms of Darcy's law with the known pressure, the mass balance equation and the irrotationality condition. These post-processing techniques are then combined with semidiscrete or space-time SUPG or GLS formulations with shock capturing. We also address in this paper issues related to the improvement of computational efficiency of our methods. Among then we will show reduced integration techniques with hourglass control for the elliptic, post-processing and transport equations, its association to superconvergent techniques for gradient recovery, adaptive time stepping strategies based on feedback control theory and parallel element-by-element strategies. Extensive numerical results will show the effectiveness of our approach. (author)

  17. Particle flow modelling on spiral concentrators: benefits of dense media for coal processing?

    Energy Technology Data Exchange (ETDEWEB)

    Matthews, B.W.; Fletcher, C.A.J.; Partridge, T.C. [University of New South Wales, Sydney, NSW (Australia). Centre for Advanced Numerical Computation in Engineering and Science

    1999-07-01

    Spiral concentrators consists of an open trough that twists downward in helix configuration about a central axis. Particles fed to the top of the concentrator are separated radially on the basis of density and size as the slurry gravitates downward. To improve performance, CFD studies validated against experimental programs have been performed throughout the past decade. The CFD model development is now sufficiently advanced to predict reliably the free surface liquid and particle flow characteristics at concentrations where the particle-particle interactions are significant. The main focus of the paper examines computationally the potential of using dense media for coal processing by increasing the fluid density above that of water. 15 refs., 11 figs.

  18. Rapid Determination of Optimal Conditions in a Continuous Flow Reactor Using Process Analytical Technology

    Directory of Open Access Journals (Sweden)

    Michael F. Roberto

    2013-12-01

    Full Text Available Continuous flow reactors (CFRs are an emerging technology that offer several advantages over traditional batch synthesis methods, including more efficient mixing schemes, rapid heat transfer, and increased user safety. Of particular interest to the specialty chemical and pharmaceutical manufacturing industries is the significantly improved reliability and product reproducibility over time. CFR reproducibility can be attributed to the reactors achieving and maintaining a steady state once all physical and chemical conditions have stabilized. This work describes the implementation of a smart CFR with univariate physical and multivariate chemical monitoring that allows for rapid determination of steady state, requiring less than one minute. Additionally, the use of process analytical technology further enabled a significant reduction in the time and cost associated with offline validation methods. The technology implemented for this study is chemistry and hardware agnostic, making this approach a viable means of optimizing the conditions of any CFR.

  19. Simulating the process flow of the Nikon EPL new geometry mask

    Science.gov (United States)

    Chang, Jaehyuk; Engelstad, Roxann L.; Lovell, Edward G.; Sogard, Michael R.

    2004-12-01

    The International Technology Roadmap for Semiconductors requires improvements in resolution for each lithographic node. In order to meet the resolution requirements for the sub-65-nm nodes, image placement (IP) errors induced by chucking the mask during e-beam patterning, metrology, and exposure must be characterized and minimized. This study focused on a 200-mm electron projection lithography (EPL) stencil mask designed for high throughput. Finite element models were developed to simulate the response of the mask throughout a typical fabrication process flow, including the electrostatic chucking during e-beam patterning and EPL exposure. The results of this predictive study were used to identify the primary sources of IP error as a function of the system parameters.

  20. 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.

  1. 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.

  2. 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 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.)

  3. Algebraic Generalization of Venn Diagram

    OpenAIRE

    Florentin Smarandache

    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.

  4. Higher Order City Voronoi Diagrams

    CERN Document Server

    Gemsa, Andreas; Liu, Chih-Hung; Wagner, Dorothea

    2012-01-01

    We investigate higher-order Voronoi diagrams in the city metric. This metric is induced by quickest paths in the L1 metric in the presence of an accelerating transportation network of axis-parallel line segments. For the structural complexity of kth-order city Voronoi diagrams of n point sites, we show an upper bound of O(k(n - k) + kc) and a lower bound of {\\Omega}(n + kc), where c is the complexity of the transportation network. This is quite different from the bound O(k(n - k)) in the Euclidean metric. For the special case where k = n - 1 the complexity in the Euclidean metric is O(n), while that in the city metric is {\\Theta}(nc). Furthermore, we develop an O(k^2(n + c) log n)-time iterative algorithm to compute the kth-order city Voronoi diagram and an O(nc log^2(n + c) log n)-time divide-and-conquer algorithm to compute the farthest-site city Voronoi diagram.

  5. The diagram for phyllotactic series

    Directory of Open Access Journals (Sweden)

    Joanna Szymanowska-Pu?ka

    2014-02-01

    Full Text Available Many authors studying phyllotaxis in various plant species have reported the occurrence of many different numbers of contact parastichy pairs that are members of different Fibonacci-like series. On the basis of these reports a diagram was constructed in which any theoretically possible series was represented by the two first members of a given series.

  6. Telesynergy V3 Wiring Diagram

    Science.gov (United States)

    Extron 8 port Video/Audio Switch WAVE Camera Telesynergy v3 Wiring Diagram ISDN T1/PRI Module CTRLR 0 Legend: S-Video Audio VGA DVI USB RS-232 Serial Microphone Ethernet Planar C5i AMD Exam Cam Canon Document Camera Olympus BX51 Sony DVD Recorder JVC

  7. 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.

  8. 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,

  9. 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.

  10. 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.

  11. Simulation and fabrication of micro-scaled flow channels for metallic bipolar plates by the electrochemical micro-machining process

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Shuo-Jen; Lee, Chi-Yuan; Yang, Kung-Ting; Kuan, Feng-Hui; Lai, Ping-Hung [Department of Mechanical Engineering, Yuan Ze Fuel Cell Center, Yuan Ze University, 135 Far East Road, Nei-Li, Tao-Yuan (China)

    2008-12-01

    In order to take better advantage of metallic bipolar plates for producing metallic fuel cells and make it a feasible technology, it is essential that we have an efficient and cost effective fabrication process for creating micro-scaled flow channels. In this study, an electrochemical micro-machining (EMM) process is developed. In order to have better process control a finite element analysis is employed to ensure machine tool platform rigidity; an electric field analysis is applied for the electrode design; and an electrolytic flow analysis is carried out for the fixture design and the selection of the operational parameter. Finally, flow channels measuring 200 {mu}m in depth and 500 {mu}m in width are fabricated on SS316 stainless steel sheets measuring 50 mm x 0.6 mm thick. (author)

  12. [Influence of image process on fractal morphology characterization of NAPLs vertical fingering flow].

    Science.gov (United States)

    Li, Hui-Ying; Du, Xiao-Ming; Yang, Bin; Wu, Bin; Xu, Zhu; Shi, Yi; Fang, Ji-Dun; Li, Fa-Sheng

    2013-11-01

    Dyes are frequently used to visualize fingering flow pathways, where the image process has an important role in the result analysis. The theory of fractal geometry is applied to give quantitative description of the stain patterns via image analysis, which is helpful for finger characterization and prediction. This description typically involves two parameters, a mass fractal dimension (D(m)) relative to the area, and a surface fractal dimension (D(s)) relative to the perimeter. This work detailed analyzes the influence of various choices during the thresholding step that transformed the origin color images to binary ones which are needed in the fractal analysis. One hundred and thirty images were obtained from laboratory two-dimension sand box infiltration experiments of four dyed non-aqueous phase liquids. Detailed comparisons of D(m) and D(s) were made respectively, considering a set of threshold algorithms and the filling of lakes. Results indicate that adjustments of the saturation threshold influence are less on both D(m) and D(s) in the laboratory experiments. The brightness threshold adjustments decrease the D(m) by 0.02 and increase the D(s) by 0.05. Filling lakes influence the D(m) less while the D(s) decrease by 0.10. Therefore the D(m) was recommended for further analysis to avoid subjective choices' influence in the image process. PMID:24455950

  13. Interaction of density flow and geochemical processes on islands in the Okavanga Delta, Botswana

    DEFF Research Database (Denmark)

    Bauer-Gottwein, Peter; Langer, T.; Prommer, H.; Wolski, P.; Kinzelbach, W.

    2006-01-01

    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 of...

  14. Use of soil moisture dynamics and patterns for the investigation of runoff generation processes with emphasis on preferential flow

    Directory of Open Access Journals (Sweden)

    T. Blume

    2007-08-01

    Full Text Available Spatial patterns as well as temporal dynamics of soil moisture have a major influence on runoff generation. The investigation of these dynamics and patterns can thus yield valuable information on hydrological processes, especially in data scarce or previously ungauged catchments. The combination of spatially scarce but temporally high resolution soil moisture profiles with episodic and thus temporally scarce moisture profiles at additional locations provides information on spatial as well as temporal patterns of soil moisture at the hillslope transect scale. This approach is better suited to difficult terrain (dense forest, steep slopes than geophysical techniques and at the same time less cost-intensive than a high resolution grid of continuously measuring sensors. Rainfall simulation experiments with dye tracers while continuously monitoring soil moisture response allows for visualization of flow processes in the unsaturated zone at these locations. Data was analyzed at different spacio-temporal scales using various graphical methods, such as space-time colour maps (for the event and plot scale and indicator maps (for the long-term and hillslope scale. Annual dynamics of soil moisture and decimeter-scale variability were also investigated. The proposed approach proved to be successful in the investigation of flow processes in the unsaturated zone and showed the importance of preferential flow in the Malalcahuello Catchment, a data-scarce catchment in the Andes of Southern Chile. Fast response times of stream flow indicate that preferential flow observed at the plot scale might also be of importance at the hillslope or catchment scale. Flow patterns were highly variable in space but persistent in time. The most likely explanation for preferential flow in this catchment is a combination of hydrophobicity, small scale heterogeneity in rainfall due to redistribution in the canopy and strong gradients in unsaturated conductivities leading to self-reinforcing flow paths.

  15. Use of soil moisture dynamics and patterns at different spatio-temporal scales for the investigation of subsurface flow processes

    Directory of Open Access Journals (Sweden)

    T. Blume

    2009-07-01

    Full Text Available Spatial patterns as well as temporal dynamics of soil moisture have a major influence on runoff generation. The investigation of these dynamics and patterns can thus yield valuable information on hydrological processes, especially in data scarce or previously ungauged catchments. The combination of spatially scarce but temporally high resolution soil moisture profiles with episodic and thus temporally scarce moisture profiles at additional locations provides information on spatial as well as temporal patterns of soil moisture at the hillslope transect scale. This approach is better suited to difficult terrain (dense forest, steep slopes than geophysical techniques and at the same time less cost-intensive than a high resolution grid of continuously measuring sensors. Rainfall simulation experiments with dye tracers while continuously monitoring soil moisture response allows for visualization of flow processes in the unsaturated zone at these locations. Data was analyzed at different spacio-temporal scales using various graphical methods, such as space-time colour maps (for the event and plot scale and binary indicator maps (for the long-term and hillslope scale. Annual dynamics of soil moisture and decimeter-scale variability were also investigated. The proposed approach proved to be successful in the investigation of flow processes in the unsaturated zone and showed the importance of preferential flow in the Malalcahuello Catchment, a data-scarce catchment in the Andes of Southern Chile. Fast response times of stream flow indicate that preferential flow observed at the plot scale might also be of importance at the hillslope or catchment scale. Flow patterns were highly variable in space but persistent in time. The most likely explanation for preferential flow in this catchment is a combination of hydrophobicity, small scale heterogeneity in rainfall due to redistribution in the canopy and strong gradients in unsaturated conductivities leading to self-reinforcing flow paths.

  16. 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

  17. 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.

  18. Delayed onset of return flow by substrate inclination in model horizontal longitudinal MOCVD processes

    Science.gov (United States)

    Kuo, W. S.; Wang, C. Y.; Tuh, J. L.; Lin, T. F.

    2005-01-01

    In this study an experimental flow visualization is carried out to investigate how the substrate inclination affects the buoyancy-induced return flow structure in mixed convection of gas in a horizontal rectangular duct. The return flow is driven by a heated circular disk embedded in the bottom plate of the duct, simulating that in a horizontal longitudinal MOCVD reactor. Specifically, the bottom plate of the duct is inclined so that the gas flow in the duct is accelerated, causing the buoyancy-to-inertia ratio to decrease in the main flow direction. In the experiment, the Reynolds and Rayleigh numbers of the flow at the duct inlet are respectively varied from 3.7 to 79.7 and from 9040 to 24,000 for the inclined angle of the bottom plate fixed at 0°, 0.34° and 0.97°. Particular attention is paid to delineating the spatial changes of the return flow structure with the plate inclination angle and to how the bottom plate tilting possibly suppresses and stabilizes the flow. The results show a substantial delay in the onset of the return flow and the effective suppression of the buoyancy-driven unstable vortex flow by the bottom plate inclination. Besides, the bottom plate inclination can effectively weaken the return flow at slightly higher Reynolds numbers. An empirical equation is provided to correlate the present data for the onset of the return flow in the duct with its bottom inclined at 0° and 0.97°.

  19. Groundwater hydrochemical characteristics and processes along flow paths in the North China Plain

    Science.gov (United States)

    Xing, Lina; Guo, Huaming; Zhan, Yanhong

    2013-07-01

    The North China Plain is one of the biggest plains in China, where municipal, agricultural and industrial water supplies are highly dependent on groundwater resources. It is crucial to investigate water chemistry and hydrogeochemical processes related to hydrogeologic settings for sustainable utilization of groundwater resources. Two hydrochemical profiles proximately along the groundwater flow paths were selected for hydrogeochemical study. Major components and 2H and 18O isotopes were analyzed in groundwater samples from the profiles. The study area was divided into three zones, including strong runoff-alluvial/pluvial fans in the piedmont area (Zone I), slow runoff-alluvial/lacustrine plain in the central area (Zone II), and discharge-alluvial/marine plain in the coastal area (Zone III). Major components of groundwater samples showed obvious zonation patterns from Zone I to Zone III. Total dissolved solid (TDS) concentrations gradually increased, and the hydrochemical type changed from HCO3-SO4-Ca-Mg and HCO3-Cl-Ca-Mg types to HCO3-SO4-Na-Ca, SO4-Cl-Na-Ca and SO4-Cl-Na types from Zone I to Zone III. Abrupt increases in concentrations of Na+, Cl- and SO42- in deep groundwater were observed around the depression cones, which indicated that overexploitation resulted in water quality deterioration. Calcite and dolomite precipitation occurred in Zone I of deep groundwater systems and shallow groundwater systems. Cation exchange was believed to take place along the entire flow paths. Gypsum tended to dissolve in groundwater systems. The depletion in D and 18O isotopes in deep groundwater was related to the recharge from precipitation in paleo-climate conditions in glacial or interglacial periods, indicating that renewal groundwater was very limited. Efficient strategies must be taken to preserve the valued water resources for sustainable development.

  20. Self Cleaning High Efficiency Particulate Air (HEPA) Filtration without Interrupting Process Flow - 59347

    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 suggests that the then costs to the Department of Energy (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 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)

  1. Characterization of flow and infiltration processes on agricultural plots irrigated by submersion.

    Science.gov (United States)

    Alkassem Alosman, Mohamed; Ruy, Stéphane; Olioso, Albert; Bader, Jean Claude; Buis, Samuel; Lecharpentier, Patrice; Charron, Francois

    2015-04-01

    The surface irrigation (flood irrigation, trickle and furrow) is a traditional irrigation system widely used worldwide. This system is recognized as being highly water consumer: high volumes of water are injected to the plot, which generate significant loss of water (drainage and run-off). Although these unused water flows can generate positive externalities (feeding wetlands, groundwater recharge) a decrease of water volume used is sought in a context of limited water resource. In this system of irrigation, the amount of water that is actually brought to the plot surface ("irrigation dose") is insufficiently known because it depends on the interaction between the propagation of water at surface of the plot and its infiltration into the soil. These two processes are conditioned by multiple factors: input flow rate in the plot, irrigation duration, soil properties (hydraulic conductivity, water reserve and depth), geometry of the parcel, hydraulic factors (slope of flow, coefficient of friction hydraulic). A methodology is therefore needed for calculating the doses given on an agricultural plot in order to analyse current practices and to propose ways for optimization. The aim of this study is to develop a methodology to estimate (i) the amount of infiltrated water at the scale of a flood irrigated agricultural field, and (ii) soil properties (permeability, useful water reserve). This work is based on the use of a flood irrigation model (CALHY, model Bader et al., 2010, Hydrol. Sci. J., 55, 177-191) combined with a device for tracking the infiltration and the advancing of water in several fields of hay which are irrigated through submersion. Firstly, a sensitivity analysis was used to define an optimal experimental configuration with respect to the estimation of parameters of interest (hydraulic friction, soil water storage capacity, hydraulic conductivity, soil depth). This analysis was performed on each of the model parameters and for different output variables. The results show that the sensitivity depends on the type of output studied and on its localization in the field. In a second step, numerical experiments were performed to determine the type of parameter that can be estimated by inversion: we show that the knowledge of the evolution of water heights in two cross sections (upstream and downstream parts of the plot) and other related outputs are enough for estimate all the necessary parameters for calculating the water balance . Prospects are (I) to optimize the calculation of the parameters by the inversion of the model, (II) to spatialize the model at the scale of the entire landscape and (III) to compute the water balance of flood irrigated plots at the regional scale.

  2. The flow behavior and processing maps during the isothermal compression of Ti17 alloy

    International Nuclear Information System (INIS)

    Isothermal compression tests of Ti17 alloy were conducted on a Gleeble-1500 simulator at the deformation temperatures ranging from 770 °C to 870 °C, strain rates ranging from 0.01 s?1 to 5.0 s?1, and strains ranging from 0.5 to 0.9. The effect of processing parameters on the flow stress and strain rate sensitivity (m) was investigated to characterize the deformation behavior of Ti17 alloy. The processing maps based on dynamic material modeling (DMM) were developed at different strains to represent the deformation mechanisms during the isothermal compression of Ti17 alloy. Moreover, the microstructure evolution was observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to verify the deformation mechanisms. The results show that the maximum m value of 0.42 occurs at 770 °C/0.01 s?1. High ductility value of about 180% in this domain confirms the superplastic deformation behavior of the material. The unstable domains in instability map increase at the strains ranging from 0.3 to 0.7, which implies that the processing window of Ti17 alloy becomes narrow with increasing strain. The peak efficiency of power dissipation occurs at 770 °C/0.01 s?1 and the strains range from 0.3 to 0.6, corresponding to the optimal deformation condition of Ti17 alloy. By the analysis of microstructure evolution of Ti17 alloy, it is confirmed that dynamic recrystallization occurs at 790 °C/0.01 s?1 and dynamic recovery is a dominant softening mechanism at higher strain rates (?1.0 s?1)

  3. NIST Phase Equilibria Diagrams Database - SRD 31

    Data.gov (United States)

    National Institute of Standards and Technology, Department of Commerce — The Phase Equilibria Diagrams Database contains commentaries and more than 21,000 diagrams for non-organic systems, including those published in all 21 hard-copy...

  4. Single-ensemble-based eigen-processing methods for color flow imaging--Part II. The matrix pencil estimator.

    Science.gov (United States)

    Yu, Alfred C H; Cobbold, Richard S C

    2008-03-01

    Parametric spectral estimators can potentially be used to obtain flow estimates directly from raw slow-time ensembles whose clutter has not been suppressed. We present a new eigen-based parametric flow estimation method called the matrix pencil, whose principles are based on a matrix form under the same name. The presented method models the slow-time signal as a sum of dominant complex sinusoids in the slow-time ensemble, and it computes the principal Doppler frequencies by using a generalized eigen-value problem-formulation and matrix rank reduction principles. Both fixed rank (rank-one, rank-two) and adaptive-rank matrix pencil flow estimators are proposed, and their potential applicability to color flow signal processing is discussed. For the adaptive-rank estimator, the nominal rank was defined as the minimum eigen-structure rank that yields principal frequency estimates with a spread greater than a prescribed bandwidth. In our initial performance evaluation, the fixed-rank matrix pencil estimators were applied to raw color flow data (transmit frequency: 5 MHz; pulse repetition period: 0.175 ms; ensemble size: 14) acquired from a steady flow phantom (70 cm/s at centerline) that was surrounded by rigid-tissue-mimicking material. These fixed-rank estimators produced velocity maps that are well correlated with the theoretical flow profile (correlation coefficient: 0.964 to 0.975). To facilitate further evaluation, the matrix pencil estimators were applied to synthetic slow-time data (transmit frequency: 5 MHz; pulse repetition period: 1.0 ms; ensemble size: 10) modeling flow scenarios without and with tissue motion (up to 1 cm/s). The bias and root-mean-squared error of the estimators were computed as a function of blood-signal-to-noise ratio and blood velocity. The matrix pencil flow estimators showed that they are comparatively less biased than most of the existing frequency-based flow estimators like the lagone autocorrelator. PMID:18407848

  5. EDU power output upgrade - NRI participation in this process

    International Nuclear Information System (INIS)

    The topics described include: Time schedule of fuel licensing for design margin utilization at the Dukovany NPP (EDU VPR); Strategy of Gd-2M fuel licensing + EDU VPR Project; Documentation development; Fuel; Mechanical part; Impact on unit equipment; Heat flow diagram; Impact on the existing Dukovany PSAR; VPR project impact on the equipment qualification process; and Authorities. (P.A.)

  6. Phase Diagrams in Chemical Engineering: Application to Distillation and Solvent Extraction

    OpenAIRE

    Coquelet, Christophe; Ramjugernath, Deresh

    2012-01-01

    A phase diagram in physical chemistry and chemical engineering is a graphical representation showing distinct phases which are in thermodynamic equilibrium. Since these equilibrium relationships are dependent on the pressure, temperature, and composition of the system, a phase diagram provides a graphical visualization of the effects of these system variables on the equilbrium behavior between the phases. Phase diagrams are essential in the understanding and development of separation processe...

  7. A three-dimensional viscous flow analysis for the helicopter tip vortex generation process about square and round tipped blades

    Science.gov (United States)

    Lin, S.-J.; Levy, R.; Shamroth, S. J.

    1986-01-01

    The tip vortex flow field occurring in the vicinity of the tip region of a helicopter rotor blade is a very complicated three-dimensional, viscous flow phenomenon. The details of the flow in the tip region can have a major effect in determining the generated rotor noise and can significantly effect the performance and dynamic loading of the rotor blade. The three-dimensional viscous subsonic tip vortex generation processes is investigated by a numerical procedure which allows spatial forward-marching integration, utilizing flow approximations from the velocity-decomposition approach of Briley and McDonald. The approach has been applied to compute the laminar and turbulent tip vortex flows for a constant thickness slab airfoil with a square tip, a constant thickness slab airfoil with a half round tip and a NACA 0012 airfoil with a half round tip. The basic mechanism of the tip vortex generation process as well as the prediction of vortex appearance, strength and secondary flow shown by the calculations are in qualitative agreement with experimental results.

  8. Multi-currency Influence Diagrams

    DEFF Research Database (Denmark)

    Nielsen, SØren Holbech; Nielsen, Thomas Dyhre

    2007-01-01

    When using the influence diagrams framework for solving a decision problem with several different quantitative utilities, the traditional approach has been to convert the utilities into one common currency. This conversion is carried out using a tacit transformation, under the assumption that the converted problem is equivalent to the original one. In this paper we present an extension of the influence diagram framework. The extension allows for these decision problems to be modelled in their original form. We present an algorithm that, given a linear conversion function between the currencies of the original utilities, discovers a characterisation of all other such functions, which induce the same optimal strategy. As this characterisation can potentially be very complex, we give methods to present it in an approximate way.

  9. Hero's journey in bifurcation diagram

    Science.gov (United States)

    Monteiro, L. H. A.; Mustaro, P. N.

    2012-06-01

    The hero's journey is a narrative structure identified by several authors in comparative studies on folklore and mythology. This storytelling template presents the stages of inner metamorphosis undergone by the protagonist after being called to an adventure. In a simplified version, this journey is divided into three acts separated by two crucial moments. Here we propose a discrete-time dynamical system for representing the protagonist's evolution. The suffering along the journey is taken as the control parameter of this system. The bifurcation diagram exhibits stationary, periodic and chaotic behaviors. In this diagram, there are transition from fixed point to chaos and transition from limit cycle to fixed point. We found that the values of the control parameter corresponding to these two transitions are in quantitative agreement with the two critical moments of the three-act hero's journey identified in 10 movies appearing in the list of the 200 worldwide highest-grossing films.

  10. The spectroscopic Hertzsprung-Russell diagram

    OpenAIRE

    Langer, N.; Kudritzki, R. P.

    2014-01-01

    The Hertzsprung-Russell diagram is an essential diagnostic diagram for stellar structure and evolution, which has now been in use for more than 100 years. Our spectroscopic Hertzsprung-Russell (sHR) diagram shows the inverse of the flux-mean gravity versus the effective temperature. Observed stars whose spectra have been quantitatively analyzed can be entered in this diagram without the knowledge of the stellar distance or absolute brightness. Observed stars can be as conven...

  11. Properties of pedestrians walking in line - Fundamental diagrams

    OpenAIRE

    Jeli?, Asja; Appert-Rolland, Cécile; Lemercier, Samuel; Pettré, Julien

    2011-01-01

    We present experimental results obtained for a one-dimensional flow using high precision motion capture. The full pedestrians' trajectories are obtained. In this paper, we focus on the fundamental diagram, and on the relation between the instantaneous velocity and spatial headway (distance to the predecessor). While the latter was found to be linear in previous experiments, we show that it is rather a piecewise linear behavior which is found if larger density ranges are cove...

  12. Macroscopic travel time reliability diagrams for freeway networks:

    OpenAIRE

    Tu, H.; Li, H; Van Lint, J.W.C.; Knoop, V.L.; SUN, L.

    2013-01-01

    Travel time reliability is considered to be one of the key indicators of transport system performance. Knowledge of the mechanisms of travel time unreliability enables the derivation of explanatory models with which travel time reliability can be predicted and utilized in traffic management. Inspired by the macroscopic fundamental diagram (MFD), describing the relationship between production (average flow completing the trips) and vehicle accumulation (average density) in a traffic network, t...

  13. Comparative Study on DFD to UML Diagrams Transformation

    OpenAIRE

    Aamer Nadeem; Muhammad Usma; Atif A. A. Jilani; Zafar I. Malik; Zahid Halim

    2011-01-01

    Most of legacy systems use nowadays were modeled and documented using structured approach. Expansion of these systems in terms of functionality and maintainability requires shift towards object-oriented documentation and design, which has been widely accepted by the industry. In this paper, we present a survey of the existing Data Flow Diagram (DFD) to Unified Modeling language (UML) transformation techniques. We analyze transformation techniques using a set of parameters, identified in the s...

  14. Spectral interpretation of decision diagrams

    CERN Document Server

    Stankovic, Radomir

    2006-01-01

    Interpreting decision diagrams using the spectral approach advances both the utility and understanding of classical DD techniques and provides a framework for developing advanced solutions for digital design and a host of other applications. Scientists, computer science and engineering professionals, and researchers with an interest in the spectral methods of representing discrete functions, as well as the foundations of logic design, will find the book a clearly explained, well-organized, and essential resource.

  15. Phase diagram of Janus Particles

    OpenAIRE

    Sciortino Francesco; Giacometti Achille; Pastore Giorgio

    2009-01-01

    We deeply investigate a simple model representative of the recently synthesized Janus particles, i.e. colloidal spherical particles whose surface is divided into two areas of different chemical composition. When the two surfaces are solvophilic and solvophobic, these particles constitute the simplest example of surfactants. The phase diagram includes a colloidal-poor (gas) colloidal-rich (liquid) de-mixing region, which is progressively suppressed by the insurgence of micell...

  16. Fast Evaluation of Feynman Diagrams

    OpenAIRE

    Easther, Richard; Guralnik, Gerald; Hahn, Stephen

    1999-01-01

    We develop a new representation for the integrals associated with Feynman diagrams. This leads directly to a novel method for the numerical evaluation of these integrals, which avoids the use of Monte Carlo techniques. Our approach is based on based on the theory of generalized sinc ($\\sin(x)/x$) functions, from which we derive an approximation to the propagator that is expressed as an infinite sum. When the propagators in the Feynman integrals are replaced with the approxim...

  17. Phase diagrams for surface alloys

    DEFF Research Database (Denmark)

    Christensen, Asbjørn; Ruban, Andrei; Stoltze, Per; Jacobsen, Karsten Wedel; Skriver, Hans Lomholt; Nørskov, Jens Kehlet; Besenbacher, Flemming

    1997-01-01

    We discuss surface alloy phases and their stability based on surface phase diagrams constructed from the surface energy as a function of the surface composition. We show that in the simplest cases of pseudomorphic overlayers there are four generic classes of systems, characterized by the sign of the heat of segregation from the bulk and the sign of the excess interactions between the atoms in the surface (the surface mixing energy). We also consider the more complicated cases a with ordered surf...

  18. Bayesian Networks and Influence Diagrams

    DEFF Research Database (Denmark)

    Kjærulff, Uffe Bro; Madsen, Anders Læsø

    2013-01-01

    Bayesian Networks and Influence Diagrams: A Guide to Construction and Analysis, Second Edition, provides a comprehensive guide for practitioners who wish to understand, construct, and analyze intelligent systems for decision support based on probabilistic networks. This new edition contains six new sections, in addition to fully-updated examples, tables, figures, and a revised appendix. Intended primarily for practitioners, this book does not require sophisticated mathematical skills or deep und...

  19. Experimental study of multiphase flow in porous media during CO{sub 2} geo-sequestration processes

    Energy Technology Data Exchange (ETDEWEB)

    Saeedi, Ali [Curtin Univ., Kensington (Australia). Dept. of Petroleum Engineering

    2012-07-01

    There have been numerous computer-based simulation studies carried out on the subject of CO{sub 2} geo-sequestration. However, the amount of experimental data available in the literature on this topic, especially with regards to multiphase flow characteristics of fluid-rock systems during such processes, is very limited. This research was carried out with the aim of providing a better understanding of the multiphase fluid flow characteristics of fluid-rock systems during the geo-sequestration process. The ultimate goal of this research was to experimentally evaluate the change in a number of multiphase flow characteristics of the system over time caused by the potential chemical and physical/mechanical processes occurring during deep CO{sub 2} disposal. In order to achieve this goal the effects of cyclic/alternating CO{sub 2}-brine flooding, flow direction, existence of residual hydrocarbon (natural gas) and change in the reservoir stress field on the system's multiphase flow behaviour were investigated. Until completion of this study there were no experimental data published in the literature addressing the above mentioned issues and the results obtained, and published within this thesis were the first of their kind.

  20. Flow and microstructure development of a near-alpha titanium alloy during thermomechanical processing

    Science.gov (United States)

    Vo, Phuong

    The flow and beta recrystallization behaviour during thermomechanical processing of near-alpha titanium alloy IMI834 (Ti-5.8Al-4Sn-4Zr-1Nb-0.5Mo-0.35Si), with an initial bimodal alpha+beta microstructure, has been investigated. The effects of temperature and strain rate were characterized and modelled at beta and alpha+beta hot working temperatures near the beta?alpha+beta transition temperature (beta transus) to study the quantitative differences in one- and two-phase isothermal forging. The experimental work for characterization and modelling was based on compression testing of lab-scale specimens at temperatures of 975-1100°C, strain rates of 0.01-1s-1, and post-deformation annealing times of 5-420s. Supplementary interrupted compression testing was also performed at 975-1000°C to evaluate the applicability of fractional softening in the determination of static recrystallization kinetics. The stress-strain analysis, which employed corrections for friction and deformation heating, showed increasing stress at increasing strain rates and decreasing temperatures. The stress-temperature dependence increased below the beta transus due to the increasing alpha phase fraction with decreasing temperature. Microstructural observation through optical microscopy indicated dynamic recrystallization occurred, although complete grain refinement and homogeneity was only achieved following static recrystallization. Quantitative measurement via image analysis revealed static recrystallization kinetics increased with temperature for single phase beta pre-deformation microstructures (1060-1100°C). However, bimodal alpha+beta microstructures (1000-1025°C) displayed greater recrystallization rates with decreasing temperature. This behaviour was attributed to the associated increase in alpha phase fraction, which yielded a refinement in initial beta grain size and an increase in favourable nucleation sites. Interrupted compression testing of initial alpha+beta microstructures with lamellar alpha in the beta matrix (975°C) indicated that static recrystallization kinetics may have been comparable to that obtained at 1000°C, although confirmation through optical microscopy and image analysis was not feasible. At all temperatures, increasing strain rate accelerated recrystallization kinetics due to less time for dynamic recovery. A finite element model of the experimental setup, coupling heat transfer, flow behaviour and microstructure evolution, has been developed using constitutive equations adapted from available literature. The agreement between finite element model predictions and raw experimental data served as a validation of the data analysis. Stress was modelled through a self-consistent method capable of predicting flow partitioning between phases. The flow model, which had been originally developed for alpha+beta alloys, was extended to stress prediction in IMI834 and other near-alpha alloys. The microstructure was subsequently modelled through beta static recrystallization kinetics using an Avrami-type relationship.

  1. Chemical characterization of milk after treatment with thermal (HTST and UHT) and nonthermal (turbulent flow ultraviolet) processing technologies.

    Science.gov (United States)

    Cappozzo, Jack C; Koutchma, Tatiana; Barnes, Gail

    2015-08-01

    As a result of growing interest to nonthermal processing of milk, the purpose of this study was to characterize the chemical changes in raw milk composition after exposure to a new nonthermal turbulent flow UV process, conventional thermal pasteurization process (high-temperature, short-time; HTST), and their combinations, and compare those changes with commercially UHT-treated milk. Raw milk was exposed to UV light in turbulent flow at a flow rate of 4,000L/h and applied doses of 1,045 and 2,090 J/L, HTST pasteurization, and HTST in combination with UV (before or after the UV). Unprocessed raw milk, HTST-treated milk, and UHT-treated milk were the control to the milk processed with the continuous turbulent flow UV treatment. The chemical characterization included component analysis and fatty acid composition (with emphasis on conjugated linoleic acid) and analysis for vitamin D and A and volatile components. Lipid oxidation, which is an indicator to oxidative rancidity, was evaluated by free fatty acid analysis, and the volatile components (extracted organic fraction) by gas chromatography-mass spectrometry to obtain mass spectral profile. These analyses were done over a 14-d period (initially after treatment and at 7 and 14 d) because of the extended shelf-life requirement for milk. The effect of UV light on proteins (i.e., casein or lactalbumin) was evaluated qualitatively by sodium dodecyl sulfate-PAGE. The milk or liquid soluble fraction was analyzed by sodium dodecyl sulfate-PAGE for changes in the protein profile. From this study, it appears that continuous turbulent flow UV processing, whether used as a single process or in combination with HTST did not cause any statistically significant chemical changes when compared with raw milk with regard to the proximate analysis (total fat, protein, moisture, or ash), the fatty acid profile, lipid oxidation with respect to volatile analysis, or protein profile. A 56% loss of vitamin D and a 95% loss of vitamin A content was noted after 7 d from the continuous turbulent flow UV processing, but this loss was equally comparable to that found with traditional thermal processing, such as HTST and UHT. Chemical characterization of milk showed that turbulent flow UV light technology can be considered as alternative nonthermal treatment of pasteurized milk and raw milk to extend shelf life. PMID:26026762

  2. Flow rate effect on the structure and morphology of molybdenum oxide nanoparticles deposited by atmospheric-pressure microplasma processing

    Energy Technology Data Exchange (ETDEWEB)

    Bose, Arumugam Chandra [Nanoarchitectonics Research Center (NARC), National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, (Japan); Shimizu, Yoshiki [Nanoarchitectonics Research Center (NARC), National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, (Japan); Mariotti, Davide [Nanoarchitectonics Research Center (NARC), National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, (Japan); Sasaki, Takeshi [Nanoarchitectonics Research Center (NARC), National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, (Japan); Terashima, Kazuo [Department of Advanced Materials Science, Graduate School of Frontier Science, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 227-8562, (Japan); Koshizaki, Naoto [Nanoarchitectonics Research Center (NARC), National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, (Japan)

    2006-12-28

    Nanoparticles of crystalline molybdenum oxide were prepared by changing the flow rate of plasma gas (2% oxygen balanced by Ar) using an atmospheric-pressure microplasma technique. The morphology and crystalline structure of the nanoparticles were characterized by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The FESEM results revealed that the shape of the deposited nanoparticles depended on the plasma gas flow rate. The TEM results supported the FESEM observations. The transmission electron diffraction (TED) pattern revealed that the obtained nanoparticles changed from MoO{sub 2} to MoO{sub 3} with the flow-rate increase, and correspondingly the nanoparticle size drastically decreased. A process mechanism is proposed from the observations of optical emission spectroscopy (OES) during the process and consumed wire surface analysis from x-ray photoelectron spectroscopy (XPS) and FESEM studies.

  3. Diagram, a Learning Environment for Initiation to Object-Oriented Modeling with UML Class Diagrams

    Science.gov (United States)

    Py, Dominique; Auxepaules, Ludovic; Alonso, Mathilde

    2013-01-01

    This paper presents Diagram, a learning environment for object-oriented modelling (OOM) with UML class diagrams. Diagram an open environment, in which the teacher can add new exercises without constraints on the vocabulary or the size of the diagram. The interface includes methodological help, encourages self-correcting and self-monitoring, and…

  4. Investigation into P-t-x diagrams of the systems WOCl4-WCl5 and WOCl4-WCl6 as applied to processes of tungsten-containing materials chlorination

    International Nuclear Information System (INIS)

    Using the methods of tensimetrical differential thermal and X-ray diffraction analyses the WOCl4-WCl5 and WOCl4-WCL6 binary systems are studied. The P-t-x phase diagrams of the given systems are plotted. The physicochemical bases of low-temperature chlorination of wastes of hard-metal industry containing tungsten in the form of oxidic and metallized phases are studied

  5. Development of a 3-D measurement system for bubbly flow by color image processing

    International Nuclear Information System (INIS)

    This paper presents a measuring system for bubbly flow by a three-dimensional color image processing. The system is based on an usual particle tracking velocimetry (PTV). Fluorescent micro-capsules are used as the particles to track the motions of liquid. The micro-capsules shine with yellow green by an ultra-violet illumination. Incandescent lights with red-colored cellophane sheets are used as back lighting. Using the above mentioned illumination, the bubbles are colored by black, the micro-capsules by yellow green, and the background by red. A high-speed color video camera with four mirrors is used to obtain two images taken from two different directions that are diagonal from each other. The obtained images are transformed temporary to Windows-BMP files. The BMP files are divided into three different text data that represent the color values of red, green and blue, respectively. The bubbles and micro-capsules are extracted separately by using these three different data. Although the bubbles and particles are extracted precisely, the motions of them are not calculated well because diagonal two images are not sufficient for the 3-D tracking. (author)

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

    Directory of Open Access Journals (Sweden)

    Jhong-Yin Chen

    2013-05-01

    Full Text Available 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 software. This software was designed by the Laboratory Virtual Instrument Engineering Workbench, a graphical language for finding cell positions and viewing the driving trace, and the fuzzy logic method for controlling the voltage or time of an electric field. After experiments on real human leukemic cells (U-937, the success of the cell positioning rate achieved by controlling the voltage factor reaches 100% within 5 s. A greater precision is obtained when controlling the time factor, whereby the success rate reaches 100% within 28 s. Advantages in both high speed and high precision are attained if these two voltage and time control methods are combined. The control speed with the combined method is about 5.18 times greater than that achieved by the time method, and the control precision with the combined method is more than five times greater than that achieved by the voltage method.

  7. Scale-up of the Reversible Addition-Fragmentation Chain Transfer (RAFT) Polymerization Using Continuous Flow Processing

    OpenAIRE

    Nenad Micic; Alan Young; Julien Rosselgong; Christian H. Hornung

    2014-01-01

    A controlled radical polymerization process using the Reversible Addition-Fragmentation Chain Transfer (RAFT) approach was scaled up by a factor of 100 from a small laboratory scale of 5 mL to a preparative scale of 500 mL, using batch and continuous flow processing. The batch polymerizations were carried out in a series of different glass vessels, using either magnetic or overhead stirring, and different modes of heating: Microwave irradiation or conductive heating in an oil bath. The conti...

  8. Challenging and improving conceptual models for isothermal flow in unsaturated, fractured rock through exploration of small-scale processes

    Energy Technology Data Exchange (ETDEWEB)

    Glass, R.J.; Nicholl, M.J.; Tidwell, V.C. [Sandia National Labs., Albuquerque, NM (United States). Subsurface Flow and Transport Processes Lab.

    1996-07-01

    Over the past several years, the authors have performed experimental studies focused on understanding small-scale flow processes within discrete fractures and individual matrix blocks; much of the understanding gained in that time differs from that underlying the basic assumptions used in effective media representations. Here they synthesize the process level understanding gained from their laboratory studies to explore how such small-scale processes may influence the behavior of fluid flow in fracture networks and ensembles of matrix blocks at levels sufficient to impact the formulation of intermediate-scale effective media properties. They also explore, by means of a thought experiment, how these same small-scale processes could couple to produce a large-scale system response inconsistent with current conceptual models based on continuum representations of flow through unsaturated, fractured rock. Based on their findings, a number of modifications to existing dual permeability models are suggested that should allow them improved applicability; however, even with these modifications, it is likely that continuum representations of flow through unsaturated fractured rock will have limited validity and must therefore be applied with caution.

  9. Logical diagrams in Serbian medieval manuscripts

    Directory of Open Access Journals (Sweden)

    Žunji? Slobodan

    2011-01-01

    Full Text Available Visual rendering of logical relations represent an interesting, although (so far completely neglected part of Serbian medieval philosophy. The attempts to visualize conceptual connections or differences must not be viewed as sheer illustrations, let alone purely decorative ornaments, but as vivid traces of a deeper intellectual striving to gain more insight into the subject by means of certain pictorial shapes or accompanying scholia. Roughly speaking, Serbian diagrams occur in three major forms: 1 Divisions (dichotomous, trichotomous, etc representing conceptual classifications in the manner of the Porphyrian tree or its parts, 2 Reversed arches with one, two or more salient points, viz., upright or upside down triangles denoting syllogisms according to the three recognized figures and their respective aberrations (paralogisms; 3 Crossed diagonals inscribed or not into a square indicating mutual differences of the so called voces (terms or propositions. While their extremely abstract character allows shifting applications, which in turn always require a context bound interpretation, they were initially designed to serve three main goals: First, provide a backdrop for perfect definitions (genus + specific difference, second, demonstrate the flow of implication or lack of it in particular conclusions, and finally, illustrate multiple simultaneous relations which cannot be properly depicted in a linear dichotomy scheme. All these patterns, through the medium of Byzantine models they emulate or simply translate, could be traced down to the tradition of ancient commentators and ultimately Aristotle, who is widely credited with the introduction of visual representation in logic. While only some of them are still echoed in contemporary logic, they all shed an important light on the ways how ancient diagrams were used, transformed or forgotten, before modern patterns of visual representation were developed by the end of the 18th century.

  10. Phase diagram of speed gradient model with an on-ramp

    Science.gov (United States)

    Tang, Chang-Fu; Jiang, Rui; Wu, Qing-Song

    2007-04-01

    In this paper, phase transitions are investigated in speed gradient model with an on-ramp. Phase diagrams of traffic flow composed of manually driven vehicles and adaptive cruise control (ACC) vehicles are studied, respectively. The traffic flow composed of ACC vehicles is modeled by enhancing propagation speed of small disturbance. The phase diagram of traffic flow composed of manually driven vehicles is similar to that in previous works, in which such states as pinned localized cluster (PLC), moving localized cluster (MLC), triggered stop-and-go traffic (TSG), oscillatory congested traffic (OCT), and homogeneous congested traffic (HCT) are reproduced. In the phase diagram of traffic flow composed of ACC vehicles, traffic stability is enhanced and such states as PLC, MLC, and TSG disappear. Furthermore, some interesting phenomena, such as stationary OCT upstream of on-ramp and appearance of second OCT in HCT, are identified.

  11. Completely Automated Calculations of Multi-Loop Diagrams

    CERN Document Server

    Steinhauser, M

    1999-01-01

    The computation of higher order processes very often involves a large number of diagrams. In addition, it is in general not possible to solve the occurring integrals explicitly and expansions in small quantities have to be performed. This makes it necessary to automate the calculations as much as possible. A program package will be described which generates automatically the Feynman diagrams, manipulates the expressions in the desired way and performs the computation. As a physical application O(\\alpha\\alpha_s) corrections to the decay rate of the $Z$ boson into bottom quarks are discussed.

  12. Lee Slope Processes on a Small Artificial Flow-Transverse Dune

    Science.gov (United States)

    Cupp, K. C.; Lancaster, N.; Nickling, W. G.

    2005-12-01

    Sand is primarily deposited on the upper lee slope of dunes by grainfall and is transported downslope by reptation and grainflow (avalanching). Grainfall occurs as saltating sand grains from the stoss slope are blown over the dune crest and fall on the lee slope. Reptation and grainflow then transport these sand grains downslope. The resulting grainflows deposit lobes of sand, primarily on the lower lee slope, which are often preserved in the rock record. An understanding of the processes and conditions that produce lower lee slope deposits could provide important information regarding dune morphology, sand availability and transport rates as well the depositional environment. Despite their importance there have been few studies of grainfall, reptation, and grainflow because the lee slope is a fragile and easily disturbed environment. To overcome these obstacles the Wind Erosion Laboratory, Department of Geography, University of Guelph and the Desert Research Institute have constructed a dune simulation wind tunnel. The wind tunnel contains a small, but true-scale artificial flow-transverse sand dune that is 9 m long, 1.2 m high, and 1 m wide. Experiments in the wind tunnel were run at wind speeds ranging from 5 to 8 m/s measured 30 cm above the dune crest. The dune simulation wind tunnel provides an opportunity to study lee slope processes in a well-constrained environment by controlling wind speeds and direction, dune geometry and composition, and allows for extensive instrumentation and close observation of depositional processes. Experiments on the lee slope in the dune simulation wind tunnel indicate that grainfall decreases exponentially with distance from the crest. Grainfall distance downslope and magnitude increases with increasing wind speeds. Reptation transports and redistributes sand from grainfall primarily on the upper lee slope. Measurements of reptation rates and slope profiles show the formation of a large sediment bulge on the upper lee slope. Grainflow frequency increases with increasing wind speeds. Grainflows commonly originate at or near the point of reattachment of the return cell, in the area between the upper and lower lee slope. The point of reattachment of the return cell and the exponential decay rate of grainfall are two important factors in the location of the point of grainflow origination.

  13. Kennedy Space Center Orion Processing Team Planning for Ground Operations

    Science.gov (United States)

    Letchworth, Gary; Schlierf, Roland

    2011-01-01

    Topics in this presentation are: Constellation Ares I/Orion/Ground Ops Elements Orion Ground Operations Flow Orion Operations Planning Process and Toolset Overview, including: 1 Orion Concept of Operations by Phase 2 Ops Analysis Capabilities Overview 3 Operations Planning Evolution 4 Functional Flow Block Diagrams 5 Operations Timeline Development 6 Discrete Event Simulation (DES) Modeling 7 Ground Operations Planning Document Database (GOPDb) Using Operations Planning Tools for Operability Improvements includes: 1 Kaizen/Lean Events 2 Mockups 3 Human Factors Analysis

  14. Gases flow rate control device in the technological processes of ion-plasma and ion-beam deposition of multi-layer coatings

    International Nuclear Information System (INIS)

    The structure of decentralized control of various purposes technological units of ion-beam and ion-plasma multi-layer coatings deposition is considered. Block diagram of working gases flow rate control system of such units is given. The system provides constant level of pressure and working gases mixture composition in vacuum chamber during magnetron sputtering systems operation, constant ion and discharge current of ion-beam sputtering systems. Pressure, ion and discharge currents sensors and discharge optical emission sensors are used as system sensors. Electrically controlled regulating and switching valves were executive devices. Abilities of system operation in automatic mode and in cooperation with host computer are described

  15. Project Management Plan for the INEL technology logic diagrams

    International Nuclear Information System (INIS)

    This Project Management Plan (PjMP) describes the elements of project planning and control that apply to activities outlined in Technical Task Plan (TTP) ID-121117, ''Technology Logic Diagrams For The INEL.'' The work on this project will be conducted by personnel in EG ampersand G Idaho, Inc.'s Waste Technology Development Program. Technology logic diagrams represent a formal methodology to identify technology gaps or needs within Environmental Restoration/Waste Management Operations, which will focus on Office of Environmental Restoration and Waste Management (EM-50) research and development, demonstration, test, and evaluation efforts throughout the US Department of Energy complex. This PjMP describes the objectives, organization, roles and responsibilities, workscope and processes for implementing and managing the technology logic diagram for the Idaho National Engineering Laboratory project

  16. Project Management Plan for the INEL technology logic diagrams

    Energy Technology Data Exchange (ETDEWEB)

    Rudin, M.J.

    1992-10-01

    This Project Management Plan (PjMP) describes the elements of project planning and control that apply to activities outlined in Technical Task Plan (TTP) ID-121117, ``Technology Logic Diagrams For The INEL.`` The work on this project will be conducted by personnel in EG&G Idaho, Inc.`s Waste Technology Development Program. Technology logic diagrams represent a formal methodology to identify technology gaps or needs within Environmental Restoration/Waste Management Operations, which will focus on Office of Environmental Restoration and Waste Management (EM-50) research and development, demonstration, test, and evaluation efforts throughout the US Department of Energy complex. This PjMP describes the objectives, organization, roles and responsibilities, workscope and processes for implementing and managing the technology logic diagram for the Idaho National Engineering Laboratory project.

  17. Project Management Plan for the INEL technology logic diagrams

    Energy Technology Data Exchange (ETDEWEB)

    Rudin, M.J.

    1992-10-01

    This Project Management Plan (PjMP) describes the elements of project planning and control that apply to activities outlined in Technical Task Plan (TTP) ID-121117, Technology Logic Diagrams For The INEL.'' The work on this project will be conducted by personnel in EG G Idaho, Inc.'s Waste Technology Development Program. Technology logic diagrams represent a formal methodology to identify technology gaps or needs within Environmental Restoration/Waste Management Operations, which will focus on Office of Environmental Restoration and Waste Management (EM-50) research and development, demonstration, test, and evaluation efforts throughout the US Department of Energy complex. This PjMP describes the objectives, organization, roles and responsibilities, workscope and processes for implementing and managing the technology logic diagram for the Idaho National Engineering Laboratory project.

  18. Sequential Voronoi diagram calculations using simple chemical reactions

    CERN Document Server

    Costello, Ben de Lacy; Adamatzky, Andy

    2012-01-01

    In our recent paper [de Lacy Costello et al. 2010] we described the formation of complex tessellations of the plane arising from the various reactions of metal salts with potassium ferricyanide and ferrocyanide loaded gels. In addition to producing colourful tessellations these reactions are naturally computing generalised Voronoi diagrams of the plane. The reactions reported previously were capable of the calculation of three distinct Voronoi diagrams of the plane. As diffusion coupled with a chemical reaction is responsible for the calculation then this is achieved in parallel. Thus an increase in the complexity of the data input does not utilise additional computational resource. Additional benefits of these chemical reactions is that a permanent record of the Voronoi diagram calculation (in the form of precipitate free bisectors) is achieved, so there is no requirement for further processing to extract the calculation results. Previously it was assumed that the permanence of the results was also a potenti...

  19. Web-based execution of graphical work-flows: a modular platform for multifunctional scientific process automation

    International Nuclear Information System (INIS)

    The Passerelle process automation suite offers a fundamentally modular solution platform, based on a layered integration of several best-of-breed technologies. It has been successfully applied by Synchrotron Soleil as the sequencer for data acquisition and control processes on its beamlines, integrated with TANGO as a control bus and GlobalScreenTM) as the SCADA package. Since last year it is being used as the graphical work-flow component for the development of an eclipse-based Data Analysis Work Bench, at ESRF. The top layer of Passerelle exposes an actor-based development paradigm, based on the Ptolemy framework (UC Berkeley). Actors provide explicit reusability and strong decoupling, combined with an inherently concurrent execution model. Actor libraries exist for TANGO integration, web-services, database operations, flow control, rules-based analysis, mathematical calculations, launching external scripts etc. Passerelle's internal architecture is based on OSGi, the major Java framework for modular service-based applications. A large set of modules exist that can be recombined as desired to obtain different features and deployment models. Besides desktop versions of the Passerelle work-flow workbench, there is also the Passerelle Manager. It is a secured web application including a graphical editor, for centralized design, execution, management and monitoring of process flows, integrating standard Java Enterprise services with OSGi. We will present the internal technical architecture, some interesting application cases and the lessons learnt. (authors)

  20. Modelling Soil Heat and Water Flow as a Coupled Process in Land Surface Models

    Science.gov (United States)

    García González, Raquel; Verhoef, Anne; Vidale, Pier Luigi; Braud, Isabelle

    2010-05-01

    To improve model estimates of soil water and heat flow by land surface models (LSMs), in particular in the first few centimetres of the near-surface soil profile, we have to consider in detail all the relevant physical processes involved (see e.g. Milly, 1982). Often, thermal and iso-thermal vapour fluxes in LSMs are neglected and the simplified Richard's equation is used as a result. Vapour transfer may affect the water fluxes and heat transfer in LSMs used for hydrometeorological and climate simulations. Processes occurring in the top 50 cm soil may be relevant for water and heat flux dynamics in the deeper layers, as well as for estimates of evapotranspiration and heterotrophic respiration, or even for climate and weather predictions. Water vapour transfer, which was not incorporated in previous versions of the MOSES/JULES model (Joint UK Land Environment Simulator; Cox et al., 1999), has now been implemented. Furthermore, we also assessed the effect of the soil vertical resolution on the simulated soil moisture and temperature profiles and the effect of the processes occurring at the upper boundary, mainly in terms of infiltration rates and evapotranspiration. SiSPAT (Simple Soil Plant Atmosphere Transfer Model; Braud et al., 1995) was initially used to quantify the changes that we expect to find when we introduce vapour transfer in JULES, involving parameters such as thermal vapour conductivity and diffusivity. Also, this approach allows us to compare JULES to a more complete and complex numerical model. Water vapour flux varied with soil texture, depth and soil moisture content, but overall our results suggested that water vapour fluxes change temperature gradients in the entire soil profile and introduce an overall surface cooling effect. Increasing the resolution smoothed and reduced temperature differences between liquid (L) and liquid/vapour (LV) simulations at all depths, and introduced a temperature increase over the entire soil profile. Thermal gradients rather than soil water potential gradients seem to cause temporal and spatial (vertical) soil temperature variability. We conclude that a multi-soil layer configuration may improve soil water dynamics, heat transfer and coupling of these processes, as well as evapotranspiration estimates and land surface-atmosphere coupling. However, a compromise should be reached between numerical and process-simulation aspects. References: Braud I., A.C. Dantas-Antonino, M. Vauclin, J.L. Thony and P. Ruelle, 1995b: A Simple Soil Plant Atmo- sphere Transfer model (SiSPAT), Development and field verification, J. Hydrol, 166: 213-250 Cox, P.M., R.A. Betts, C.B. Bunton, R.L.H. Essery, P.R. Rowntree, and J. Smith (1999), The impact of new land surface physics on the GCM simulation of climate and climate sensitivity. Clim. Dyn., 15, 183-203. Milly, P.C.D., 1982. Moisture and heat transport in hysteric inhomogeneous porous media: a matric head- based formulation and a numerical model, Water Resour. Res., 18:489-498

  1. The controlled growth of horizontally aligned single-walled carbon nanotube arrays by a gas flow process

    International Nuclear Information System (INIS)

    High-density horizontally aligned single-walled carbon nanotubes (SWCNTs) have been grown by annealing Fe catalyst in air and optimizing catalyst thickness in the gas flow process. The aligned SWCNT density reaches >60 nanotubes per 100 ?m and the length can be a few millimeters. Interestingly, the growth of aligned SWCNT arrays can be extended from the catalyst substrate to a downstream substrate across the gap between them by gas flow when the two substrates are put close to each other, and thus an aligned SWCNT array has been achieved on an isolated clean substrate.

  2. Enhanced Geothermal Systems Research and Development: Models of Subsurface Chemical Processes Affecting Fluid Flow

    Energy Technology Data Exchange (ETDEWEB)

    Moller, Nancy; Weare J. H.

    2008-05-29

    Successful exploitation of the vast amount of heat stored beneath the earth’s surface in hydrothermal and fluid-limited, low permeability geothermal resources would greatly expand the Nation’s domestic energy inventory and thereby promote a more secure energy supply, a stronger economy and a cleaner environment. However, a major factor limiting the expanded development of current hydrothermal resources as well as the production of enhanced geothermal systems (EGS) is insufficient knowledge about the chemical processes controlling subsurface fluid flow. With funding from past grants from the DOE geothermal program and other agencies, we successfully developed advanced equation of state (EOS) and simulation technologies that accurately describe the chemistry of geothermal reservoirs and energy production processes via their free energies for wide XTP ranges. Using the specific interaction equations of Pitzer, we showed that our TEQUIL chemical models can correctly simulate behavior (e.g., mineral scaling and saturation ratios, gas break out, brine mixing effects, down hole temperatures and fluid chemical composition, spent brine incompatibilities) within the compositional range (Na-K-Ca-Cl-SO4-CO3-H2O-SiO2-CO2(g)) and temperature range (T < 350°C) associated with many current geothermal energy production sites that produce brines with temperatures below the critical point of water. The goal of research carried out under DOE grant DE-FG36-04GO14300 (10/1/2004-12/31/2007) was to expand the compositional range of our Pitzer-based TEQUIL fluid/rock interaction models to include the important aluminum and silica interactions (T < 350°C). Aluminum is the third most abundant element in the earth’s crust; and, as a constituent of aluminosilicate minerals, it is found in two thirds of the minerals in the earth’s crust. The ability to accurately characterize effects of temperature, fluid mixing and interactions between major rock-forming minerals and hydrothermal and/or injected fluids is critical to predict important chemical behaviors affecting fluid flow, such as mineral precipitation/dissolution reactions. We successfully achieved the project goal and objectives by demonstrating the ability of our modeling technology to correctly predict the complex pH dependent solution chemistry of the Al3+ cation and its hydrolysis species: Al(OH)2+, Al(OH)2+, Al(OH)30, and Al(OH)4- as well as the solubility of common aluminum hydroxide and aluminosilicate minerals in aqueous brines containing components (Na, K, Cl) commonly dominating hydrothermal fluids. In the sodium chloride system, where experimental data for model parameterization are most plentiful, the model extends to 300°C. Determining the stability fields of aluminum species that control the solubility of aluminum-containing minerals as a function of temperature and composition has been a major objective of research in hydrothermal chemistry.

  3. Identification and Check of Inconsistencies between UML Diagrams

    OpenAIRE

    Xianhong Liu

    2013-01-01

    Relationships between Unified Modeling Language (UML) diagrams are complex. The complexity leads to inconsistencies between UML diagrams easily. This paper focus on how to identify and check inconsistencies between UML diagrams. 13 consistency rules are given to identify inconsistencies between the most frequent 6 types of UML diagrams in the domain of information systems analysis and design. These diagrams are as follows: Use Case Diagrams, Class Diagrams, Activity Diagrams, State Machine Di...

  4. Effects of coupled structural and diagenetic processes on deformation localization and flow properties of deformation bands in sandstone

    Science.gov (United States)

    Elliott, Sara; Eichhubl, Peter; Landry, Chris

    2014-05-01

    Deformation bands tend to restrict flow perpendicular to the bands through the combined effects of porosity reduction, mechanical grain size reduction, and preferred cementation relative to the adjacent host rock. Thus, deformation bands may impart a permeability anisotropy to reservoir rocks. Deformation bands that occur in association with reservoir scale faults can impact reservoir-scale fluid flow and fault seal behavior. Using a combination of textural imaging including SEM-based cathodoluminescence imaging, compositional analysis, and lab petrophysics, this study is designed to (1) assess the effects of coupled chemical and mechanical processes leading to deformation localization in deformation bands and (2) to quantify the effect of these processes on single and multiphase fluid flow. While the effects of mechanical processes including grain translation, rotation, and breakage have been described in detail, chemical reactions affecting flow properties have received less attention. Such chemical reactions include the precipitation of carbonate and quartz cement, dissolution and albitization of feldspar, and the neoformation and infiltration of clay minerals. It is shown that the mechanical process of deformation localization is strongly controlled by chemical processes including pre-kinematic pore-filling cement, syn-kinematic cement filling intra- and transgranular fractures, and stress-enhanced dissolution reactions. Prekinematic cements reduce the strength contrast between grain and aggregate thus favoring deformation localization into narrow, well defined deformation bands. Prekinematic cementation and compaction may even favor thoroughgoing opening mode fractures and prevent localization of deformation into deformation band. Synkinematic cements within deformation bands will result in local strain hardening of bands and thus oppose further deformation localization with increasing strain. Examples will be presented from the Mesozoic clastic sequence of the western US to illustrate these processes.

  5. Gas Hydrate Stability and Sampling: The Future as Related to the Phase Diagram

    Directory of Open Access Journals (Sweden)

    E. Dendy Sloan

    2010-12-01

    Full Text Available The phase diagram for methane + water is explained, in relation to hydrate applications, such as in flow assurance and in nature. For natural applications, the phase diagram determines the regions for hydrate formation for two- and three-phase conditions. Impacts are presented for sample preparation and recovery. We discuss an international study for “Round Robin” hydrate sample preparation protocols and testing.

  6. Modelling fluid flow in a reciprocating compressor

    Directory of Open Access Journals (Sweden)

    Tuhovcak Jan

    2015-01-01

    Full Text Available Efficiency of reciprocating compressor is strongly dependent on the valves characteristics, which affects the flow through the suction and discharge line. Understanding the phenomenon inside the compressor is necessary step in development process. Commercial CFD tools offer wide capabilities to simulate the flow inside the reciprocating compressor, however they are too complicated in terms of computational time and mesh creation. Several parameters describing compressor could be therefore examined without the CFD analysis, such is valve characteristic, flow through the cycle and heat transfer. The aim of this paper is to show a numerical tool for reciprocating compressor based on the energy balance through the cycle, which provides valve characteristics, flow through the cycle and heat losses from the cylinder. Spring-damping-mass model was used for the valve description. Boundary conditions were extracted from the performance test of 4-cylinder semihermetic compressor and numerical tool validation was performed with indicated p-V diagram comparison.

  7. Investigation of flow and transport processes at the MADE site using ensemble Kalman filter

    Science.gov (United States)

    Liu, Gaisheng; Chen, Y.; Zhang, Dongxiao

    2008-01-01

    In this work the ensemble Kalman filter (EnKF) is applied to investigate the flow and transport processes at the macro-dispersion experiment (MADE) site in Columbus, MS. The EnKF is a sequential data assimilation approach that adjusts the unknown model parameter values based on the observed data with time. The classic advection-dispersion (AD) and the dual-domain mass transfer (DDMT) models are employed to analyze the tritium plume during the second MADE tracer experiment. The hydraulic conductivity (K), longitudinal dispersivity in the AD model, and mass transfer rate coefficient and mobile porosity ratio in the DDMT model, are estimated in this investigation. Because of its sequential feature, the EnKF allows for the temporal scaling of transport parameters during the tritium concentration analysis. Inverse simulation results indicate that for the AD model to reproduce the extensive spatial spreading of the tritium observed in the field, the K in the downgradient area needs to be increased significantly. The estimated K in the AD model becomes an order of magnitude higher than the in situ flowmeter measurements over a large portion of media. On the other hand, the DDMT model gives an estimation of K that is much more comparable with the flowmeter values. In addition, the simulated concentrations by the DDMT model show a better agreement with the observed values. The root mean square (RMS) between the observed and simulated tritium plumes is 0.77 for the AD model and 0.45 for the DDMT model at 328 days. Unlike the AD model, which gives inconsistent K estimates at different times, the DDMT model is able to invert the K values that consistently reproduce the observed tritium concentrations through all times. ?? 2008 Elsevier Ltd. All rights reserved.

  8. Modeling Heat and Mass Flows due to Clathrate Hydrate Processes in Planetary Systems

    Science.gov (United States)

    Osegovic, J. P.; Max, M. D.

    2013-12-01

    Gas hydrate (clathrate) will form from a variety of gases that occur on Earth and other planets and moons in the solar system under the right conditions of pressure, temperature, and concentration. Common hydrate forming gases are N2, CO2, up to ~C5 hydrocarbons including almost ubiquitous CH4, and other small 'gas' species. All of the common gas hydrates have higher heats of crystallization and dissociation and dissolution than the phase change of water and ice. If enough gas hydrate exists in a planetary body, understanding geological processes must include thermodynamic modeling of all gases in the potential gas - liquid - solid phase systems. This is particularly important where there are large amounts of hydrate forming materials that can form mixed gas (compound) hydrate because the proportion of gas in the hydrate may be substantially different from the proportion in the gas mixture from which it has formed. This complicates the relatively simple crystallization - dissociation heat calculations for single gas hydrates. The widespread presence of hydrate forming conditions and availability of hydrate forming gas means that gas hydrate activity may be a substantial mechanism for heat redistribution on planets, moons, and larger icy bodies in the Solar System, in addition to any gaseous - liquid - solid phase change thermal effects. Because the gas hydrate chemical reaction is highly reversible, they are responsive to environmental changes. We present models of simple and compound hydrate formation that can be applied to a range of planetary systems for the purposes of determining if hydrate may be present, if hydrate is or has significantly impacted heat flows, density changes due to hydrate formation and dissociation, and how much volatiles mass may be stored in hydrate.

  9. Modeling of flow and mass transport processes in unsaturated soils in combination with technical facilities

    International Nuclear Information System (INIS)

    The modelling of complex systems such as the underground is a means to describe the processes occurring in the reality. The conducting of experiments on a model to obtain qualitative evidence about a real system is referred to as a simulation. Thereby, various models (e.g. physical and mathematical models) can be used. The unsaturated zone (vadose zone) is the region between the land surface and the water table, in which the water content is less than full saturation, and the pressure is lower than the atmospheric pressure. The unsaturated zone is very significant for agriculture, geobiology, aerobic degradation processes and groundwater recharge. The processes of water flow and solute transport in the unsaturated zone can be described by means of numerical simulation programs. The aim of the present work is a comprehensive validation of the simulation program PCSiWaPro registered (developed at the TU-Dresden, Institute of Waste Management and Contaminated Site Treatment) for different applications. Another aim of this work is to investigate the applicability of the current version of PCSiWaPro registered for different cases of a combination between the unsaturated zone and technical facilities. Four application cases with different objectives were investigated within the present work, which are: the simulation of decentralized wastewater infiltration with corresponding column and field experiments, the computation of groundwater recharge by means of lysimeters, the water balance of earth dams and the modelling of landfill covering systems. The application cases differ from each other by the objective of the simulation, the geometry, the size, the specified initial and boundary conditions, the simulation time, the applied materials, the coordinate system, the input and output data. The simulation results clearly showed that PCSiWaPro registered is applicable for all investigated cases under consideration of different flow and solute transport regimes, parameters, boundary conditions, spatial and temporal discretization, and coordinate systems. The simulation results of the experimental soil columns for the decentralized treated wastewater infiltration case showed a very good agreement between measured and computed values of water and solute balance (pressure head, flow and solute concentration) of the investigated soil types B3 (slightly silty sand), B4 (coarse sand / gravel) and B5 (medium silty sand). The root of the mean squared error (RMSE) for the computation of the pressure head was 1,84 cm at B5, 3,61 cm at B3 and 1,27 cm at B4. The relative deviation in case of pressure head computation was 2,19 % at B5, 1,3 % at B3 and 5,3 % at B4. The implementation of the sensitivity analysis of the relevant parameters for the modelling showed a very high sensitivity of the VAN GENUCHTEN parameters and the saturated hydraulic conductivity of the soil. Moreover, the parameters according to DIN 4220 led to different results than the estimated ones according to pedotransfer methods based on sieve analysis. Within the project EGSIM, which was carried out at the Institute for waste management and contaminated sites treatment in collaboration with DUALIS GmbH IT Solution, the programs SENSIT and ISSOP were developed and used for parameter identification/calibration. The results obtained in this Work showed under which conditions is a secondary treatment of full biologically treated wastewater in the soil possible, so that no unallowable pollutants entry in the groundwater occurs. With regard to the field models of this application the implementation of the rotationally symmetric coordinate system should be considered as a condition and not as an option for a better corresponding to the reality. Furthermore, different scenarios of the field models were carried out with continuous and discontinuous infiltration, as well as under different initiation areas. PCSiWaPro registered could be applied for both unsaturated and variably-saturated porous media. This could be proven by the simulation of the water balance in an earth dam. The aver

  10. Analysis of Japanese banks’ historical tree diagram

    Science.gov (United States)

    Ueno, Hiromichi; Mizuno, Takayuki; Takayasu, Misako

    2007-09-01

    By using the historical data from the Japanese banks’ database at “The Bankers Library” of Japanese Banker Association, we analyze the historical network of banks from 1868 to 2006. Firstly, we define a bank every year by a particle and draw a space-time evolution process of merger, division, establishment, and failure by a tree diagram structure. We found that the distribution of the tree basin size of real data and simulation result are mostly fitting well. Secondly, we analyze the raw data of financial statements of banks collected by the National Diet library. We confirm that the distributions of the amount of deposits have fat-tail every year, however, small deviations are observed relating to governmental policy.

  11. Effect of die shape on the metal flow pattern during direct extrusion process

    Directory of Open Access Journals (Sweden)

    Solomon, N.

    2010-10-01

    Full Text Available The geometric shape of the tools is the main factor by which an optimum technological process can be developed. In the case of extrusion process the strain distribution and other important variables that influence material structure, such as hydrostatic stress, are strongly dependent on the geometry of the die. Careful design of the extrusion die profile can therefore control the product structure and can be used to minimise the amount of inhomogeneity imparted into the product. A possibility to minimise the amount of product inhomogeneity is the using of a flat die with a fillet radius in front to the bearing surface with leads to a minimum dead zone and consequently to a minimum friction at billet-container interface. In the case of aluminium alloy type 2024, for an extrusion ratio of R=8.5, good results were obtained with a fillet radius of 3.0 mm. The experimental data have been used for the finite element numerical simulation of the extrusion process. The data obtained by numerical simulation with FORGE2 programme confirm the theoretical and experimental outcomes. The aim of this paper is to study the influence of such flat die on the material flow during direct extrusion process and consequently on extruded product microstructure and mechanical properties.La forma geométrica de las herramientas es el principal factor a través del cual un proceso óptimo de deformación plástica puede ser mejor desarrollado. En el caso del proceso de extrusión, la distribución de la deformación y otras variables importantes, como la presión hidrostática, que pueden influir en la estructura del material, son fuertemente dependientes de la geometría del molde. Mediante un diseño apropiado del perfil del molde de extrusión se pueden controlar la estructura y las propiedades mecánicas del producto y, por lo tanto, se puede utilizar para minimizar la cantidad de la no homogeneidad del producto. Una posibilidad para reducir al mínimo la cantidad de no homogeneidad del producto es utilizar un molde recto provisto de un radio de conexión en la zona de deformación, que puede causar una reducción al mínimo de la zona muerta y, así, reducir al mínimo la fricción en la interfase entre el semiacabado y el contenedor del molde. En el caso de la aleación de aluminio de tipo 2024, para una relación de extrusión, R = 8,5, los mejores resultados se obtuvieron con un radio de conexión de 3,0 mm. Los datos experimentales se utilizaron para la simulación numérica del proceso de extrusión. Los resultados experimentales obtenidos mediante el uso de simulación numérica con el programa FORGE2 confirman los resultados teóricos y experimentales. El propósito de este trabajo es estudiar la influencia de este tipo de matrices con un radio de conexión en la zona de deformación en el flujo de material durante el proceso de extrusión y por tanto en la microestructura y propiedades mecánicas del producto extruido.

  12. Magnetized effective QCD phase diagram

    Science.gov (United States)

    Ayala, Alejandro; Dominguez, C. A.; Hernández, L. A.; Loewe, M.; Zamora, R.

    2015-11-01

    The QCD phase diagram in the temperature vs quark chemical potential plane is studied in the presence of a magnetic field, using the linear sigma model coupled to quarks. It is shown that the decrease of the couplings with increasing field strength obtained in this model leads to the critical temperature for the phase transition to decrease with increasing field intensity (inverse magnetic catalysis). This happens provided that plasma screening is properly accounted for. It is also found that with increasing field strength the location of the critical end point in the phase diagram moves toward lower values of the critical quark chemical potential and larger values of the critical temperature. In addition, the critical end point approaches the temperature axis for large values of the magnetic field. We argue that a similar behavior is to be expected in QCD, since the physical impact of the magnetic field, regardless of strength, is to produce a spatial dimension reduction, whereby virtual quark-antiquark pairs are closer on average and thus the strength of their interaction decreases due to asymptotic freedom.

  13. Diagram genus, generators and applications

    CERN Document Server

    Stoimenow, A

    2011-01-01

    We continue the study of the genus of knot diagrams, deriving a new description of generators using Hirasawa's algorithm. This description leads to good estimates on the maximal number of crossings of generators and allows us to complete their classification for knots of genus 4. As applications of the genus 4 classification, we establish non-triviality of the skein polynomial on $k$-almost positive knots for $k\\le 4$, and of the Jones polynomial for $k\\le 3$. For $k\\le 4$, we classify the occurring achiral knots, and prove a trivializability result for $k$-almost positive unknot diagrams. This yields also estimates on the number of unknotting Reidemeister moves. We describe the positive knots of signature (up to) 4. Using a study of the skein polynomial, we prove the exactness of the Morton-Williams-Franks braid index inequality and the existence of a minimal string Bennequin surface for alternating knots up to genus 4. We also prove for such knots conjectures of Hoste and Fox about the roots and coefficient...

  14. The Effects of Mass Flow Rate in an Indirect Ultra-High Temperature Processing System

    OpenAIRE

    T.H. Varzakas; A.E. Labropoulos

    2007-01-01

    The effect of mass flow rate on product temperature and residence time were studied in a helically coiled, indirectly steam-heated, vertical flow, laboratory Ultra High Temperature (UHT) system equipped with automatic temperature control and recording units. With a mass flow rate of 0.54 to 3.03 kg min- 1, the Reynolds number (Re) values ranged from 1,500 to 128,000 in the various sections using water as the test product. Holding times were calculated on the basis...

  15. Development of thermodynamically-based models for simulation of hydrogeochemical processes coupled to channel flow processes in abandoned underground mines

    International Nuclear Information System (INIS)

    Accurate modeling of changing geochemistry in mine water can be an important tool in post-mining site management. The Pollutant Sources and Sinks in Underground Mines (POSSUM) model and Pollutant Loadings Above Average Pyrite Influenced Geochemistry POSSUM (PLAYING POSSUM) model were developed using object-oriented programming techniques to simulate changing geochemistry in abandoned underground mines over time. The conceptual model was created to avoid significant simplifying assumptions that decrease the accuracy and defensibility of model solutions. POSSUM and PLAYING POSSUM solve for changes in flow rate and depth of flow using a finite difference hydrodynamics model then, subsequently, solve for geochemical changes at distinct points along the flow path. Geochemical changes are modeled based on a suite of 28 kinetically controlled mineral weathering reactions. Additional geochemical transformations due to reversible sorption, dissolution and precipitation of acid generating salts and mineral precipitation are also simulated using simplified expressions. Contaminant transport is simulated using a novel application of the Random-Walk method. By simulating hydrogeochemical changes with a physically and thermodynamically controlled model, the 'state of the art' in post-mining management can be advanced.

  16. FEM analysis of metal flowing behaviors in porthole die extrusion based on the mesh reconstruction technology of the welding process

    Science.gov (United States)

    Huang, Dong-Nan; Zhang, Zhi-Hao; Li, Jing-Yuan; Xie, Jian-Xin

    2010-12-01

    A reconstruction technology of finite element meshes based on reversal engineering was applied to solve mesh penetration and separation in the finite element simulation for the divergent extrusion. The 3D numerical simulation of the divergent extrusion process including the welding stage for complicated hollow sections was conducted. Based on the analysis of flowing behaviors, the flowing velocities of the alloy in portholes and near the welding planes were properly controlled through optimizing the expansion angle as well as porthole areas and positions. After the die structure optimization, defects such as warp, wrist, and the wavelike are eliminated, which improves the section-forming quality. Meanwhile, the temperature distribution in the cross section is uniform. Especially, the temperature of the C-shape notch with a larger thickness is lower than that of other regions in the cross section, which is beneficial for balancing the alloy flowing velocity.

  17. A new continuous-flow process for catalytic conversion of glycerol to oxygenated fuel additive: Catalyst screening

    International Nuclear Information System (INIS)

    Highlights: • A continuous-flow process for catalytic synthesis of solketal from glycerol. • Six different heterogeneous acid catalysts were studied in the process. • Glycerol conversion and solketal yield of 90% and 88% respectively were achieved. • The process has the potential to be scaled-up for industrial applications. - Abstract: A new continuous-flow reactor was designed for the conversion of glycerol to solketal, an oxygenated fuel additive, through ketalization with acetone. Six heterogeneous catalysts were investigated with respect to their catalytic activity and stability in a flow reactor. The acidity of the catalysts positively influences the catalyst’s activity. Among all the solid acid catalysts tested, the maximum solketal yield from experiments at 40 °C, 600 psi and WHSV of 4 h?1 attained 73% and 88% at the acetone/glycerol molar ratio of 2.0 and 6.0, respectively, with Amberlyst Wet. Based on the solketal yield and glycerol conversion results, the activity of all catalysts tested follows the following order of sequence: Amberlyst Wet ? Zeolite ? Amberlyst Dry > Zirconium Sulfate > Montmorillonite > Polymax. An increase in acetone/glycerol molar ratio or a decrease in WHSV enhanced the glycerol conversion as expected. This process offers an attractive route for converting glycerol, the main by-product of biodiesel, to solketal – a value-added green product with potential industrial applications as a valuable fuel additive or combustion promoter for gasoline engines

  18. Ideal thermodynamic processes of oscillatory-flow regenerative engines will go to ideal stirling cycle?

    Science.gov (United States)

    Luo, Ercang

    2012-06-01

    This paper analyzes the thermodynamic cycle of oscillating-flow regenerative machines. Unlike the classical analysis of thermodynamic textbooks, the assumptions for pistons' movement limitations are not needed and only ideal flowing and heat transfer should be maintained in our present analysis. Under such simple assumptions, the meso-scale thermodynamic cycles of each gas parcel in typical locations of a regenerator are analyzed. It is observed that the gas parcels in the regenerator undergo Lorentz cycle in different temperature levels, whereas the locus of all gas parcels inside the regenerator is the Ericson-like thermodynamic cycle. Based on this new finding, the author argued that ideal oscillating-flow machines without heat transfer and flowing losses is not the Stirling cycle. However, this new thermodynamic cycle can still achieve the same efficiency of the Carnot heat engine and can be considered a new reversible thermodynamic cycle under two constant-temperature heat sinks.

  19. Study of a three-phase flow metering process for oil-water-gas flows; Etude d`un procede de mesure des debits d`un ecoulement triphasique de type eau-huile-gaz

    Energy Technology Data Exchange (ETDEWEB)

    Boyer, Ch.

    1996-11-01

    We propose a theoretical and experimental study of a three-phase flow metering process for oil-water-gas flows. The selected process is based on a combination of a mixer, a Venturi and ultrasonic methods. To perform an experimental validation of this process an instrumented set-up for three-phase air-oil-water flows has been designed, conceived and adjusted. An original theoretical model have been built to predict three-phase dispersed flows across a contraction. Once validated with two-phase air-water, oil-water and air-oil-water flows data, this model has been used to solve the Venturi metering problems. After a critical review of the available techniques, the ultrasonic propagation velocity has been selected to determine two-phase liquid-liquid flow composition. Two original models have been developed to describe the ultrasonic propagation with the dispersed phase fraction. The comparison with experimental data in oil-water flows show the superiority of one of the two models, the scattering model. For the void fraction determination in air-water flows, the work of Bensler (1990) based on the ultrasonic attenuation measurement has been extended to take into account the multiple scattering effects. Finally these techniques have been combined to determine the different flow rates in air-water, oil-water flows. For two-phase air-water and oil-water flows the problem is solved and the flow rates are measured with a very good accuracy ({+-} 3%). The results quality obtained with three-phase oil-water-gas flows and the secure theoretical bases allowing their interpretation give us the opportunity to strongly recommend the development of an industrial prototype based on the process we studied. (author) 183 refs.

  20. Bilevel fuzzy optimization to pre-process traffic data to satisfy the law of flow conservation

    OpenAIRE

    Oña, Juan de; Gómez, Penélope; Mérida-Casermeiro, Enrique

    2011-01-01

    Traffic data obtained in the field usually have some errors. For instance, traffic volume data on the various links of a network must be consistent and satisfy flow conservation, but this rarely occurs. This paper presents a method for using fuzzy optimization to adjust observed values so they meet flow conservation equations and any consistency requirements. The novelty lies in the possibility of obtaining the best combination of adjusted values, thereby preserving data integrity as much as ...

  1. Effect of the micromoulding process conditions on polymer flow behavior within a variable thickness microcavity

    OpenAIRE

    Zhiltsova, T. V.; Oliveira, M. S. A.; Ferreira, J. A.; Vasco, Joel Oliveira Correia; Pouzada, A. S.; A. J. Pontes

    2012-01-01

    Fast time to market along with high level of automation and versatility made microinjection moulding, by far, a favorite technique for the mass production of microplastic components. In the microimpressions, very high shear rates develop, eventually leading to excessive shear heating and consequently to less predictable flow behaviour comparing to conventional injection moulding. In this study, the flow behaviour within a variable thickness microimpression is investigated by monitoring pertin...

  2. A Flow Time Model for Melt-Cast Insensitive Explosive Process

    OpenAIRE

    Guillemin, Jean-Philippe; Brunet, Luc; BONNEFOY, Olivier; Thomas, Gérard

    2007-01-01

    Diphasic flows of concentrated suspensions of melt-cast insensitive explosives exhibit specific rheological properties. In order to limit the handling of pyrotechnical products presenting a risk with respect to the mechanical and thermal shocks, a lot of work has been undertaken for many years in the civil engineering sector. The objective of this study is to propose a predictive model of the flow time of a concentrated suspension through a nozzle located at the bottom of a tank. Similar to o...

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

    OpenAIRE

    Wang Pengtao; Song Yongjun; Sun Dongpo

    2013-01-01

    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 p...

  4. MINIMUM QUANTITY LUBRICANT FLOW ANALYSIS IN END MILLING PROCESSES: A COMPUTATIONAL FLUID DYNAMICS APPROACH

    Directory of Open Access Journals (Sweden)

    M. S. Najiha

    2012-12-01

    Full Text Available This paper presents a two-dimensional steady-state incompressible analysis for the minimum quantity of lubricant flow in milling operations using a computational fluid dynamics (CFD approach. The analysis of flow and heat transfer in a four-teeth milling cutter operation was undertaken. The domain of the rotating cutter along with the spray nozzle is defined. Operating cutting and boundary conditions are taken from the literature. A steady-state, pressure-based, planar analysis was performed with a viscous, realizable k-? model. A mixture of oils and air were sprayed on the tool, which is considered to be rotating and is at a temperature near the melting temperature of the workpiece. Flow fields are obtained from the study. The vector plot of the flow field shows that the flow is not evenly distributed over the cutter surface, as well as the uneven distribution of the lubricant in the direction of the cutter rotation. It can be seen that the cutting fluid has not completely penetrated the tool edges. The turbulence created by the cutter rotation in the proximity of the tool throws oil drops out of the cutting zone. The nozzle position in relation to the feed direction is very important in order to obtain the optimum effect of the MQL flow.

  5. Processes, mechanisms, parameters, and modeling approaches for partially saturated flow in soil and rock media

    International Nuclear Information System (INIS)

    This report discusses conceptual models and mathematical equations, analyzes distributions and correlations among hydrological parameters of soils and tuff, introduces new path integration approaches, and outlines scaling procedures to model potential-driven fluid flow in heterogeneous media. To properly model the transition from fracture-dominated flow under saturated conditions to matrix-dominated flow under partially saturated conditions, characteristic curves and permeability functions for fractures and matrix need to be improved and validated. Couplings from two-phase flow, heat transfer, solute transport, and rock deformation to liquid flow are also important. For stochastic modeling of alternating units of welded and nonwelded tuff or formations bounded by fault zones, correlations and constraints on average values of saturated permeability and air entry scaling factor between different units need to be imposed to avoid unlikely combinations of parameters and predictions. Large-scale simulations require efficient and verifiable numerical algorithms. New path integration approaches based on postulates of minimum work and mass conservation to solve flow geometry and potential distribution simultaneously are introduced. This verifiable integral approach, together with fractal scaling procedures to generate statistical realizations with parameter distribution, correlation, and scaling taken into account, can be used to quantify uncertainties and generate the cumulative distribution function for groundwater travel times

  6. Studying Vadose Zone Flow and Transport Processes: A Personal Look Back, ... and Forward (John Dalton Medal Lecture)

    Science.gov (United States)

    van Genuchten, Martinus Th.

    2010-05-01

    In this presentation, to be given at the occasion of my receipt of the John Dalton Medal from the European Geophysical Union, I provide a personal look back of studying subsurface flow and transport processes. Looking back, it is clear that tremendous advances have been made from the time I first started as a student some 40 years ago. Actually, compared to the thousands of years during which humans tried to manipulate the earth's surface for improved agricultural and engineering practices, it is truly amazing that Darcy's law for saturated flow was first formulated only some 150 years ago, and the Richards equation for unsaturated flow less than 80 years ago. In this presentation I will focus especially on alternative formulations for modeling fluid flow and contaminant transport in the subsurface, including the use of dual-porosity and dual-permeability models for nonequilibrium transport. The various approaches are illustrated by means of a large number of examples, from transport through well-controlled laboratory soil columns to flow and contaminant transport at the larger field scale. Looking forward, I will also give a personal view of what I believe comes next, and the topics I would work on if I could somehow start now all over again.

  7. Safety-barrier diagrams as a tool for modelling safety of hydrogen applications

    DEFF Research Database (Denmark)

    Duijm, Nijs Jan; Markert, Frank

    2009-01-01

    Safety-barrier diagrams have proven to be a useful tool in documenting the safety measures taken to prevent incidents and accidents in process industry. Especially during the introduction of new hydrogen technologies or applications, as e.g. hydrogen refuelling stations, safety-barrier diagrams are considered a valuable supplement to other traditional risk analysis tools to support the communication with authorities and other stakeholders during the permitting process. Another advantage of safety-barrier diagrams is that they highlight the importance of functional and reliable safety barriers in any system and here is a direct focus on those barriers that need to be subject to safety management in terms of design and installation, operational use, inspection and monitoring, and maintenance. Safety-barrier diagrams support both quantitative and qualitative approaches. The paper will describe the background and syntax of the methodology and demonstrate the usefulness of such diagrams for hydrogen technologies

  8. New method of massive Feynman diagrams calculation

    International Nuclear Information System (INIS)

    A new method of massive Feynman diagrams calculation which is based on the rule of integration by parts is given. This rule is expanded to the massive case. The result of the application of the rule of integration by parts is the differential equation with respect to the mass for the initial diagram. The right hand side of the equation contains simple diagrams. 23 refs

  9. Feynman diagrams and their algebraic lattices

    CERN Document Server

    Borinsky, Michael

    2015-01-01

    We present the lattice structure of Feynman diagram renormalization in physical QFTs from the viewpoint of Dyson-Schwinger-Equations and the core Hopf algebra of Feynman diagrams. The lattice structure encapsules the nestedness of diagrams. This structure can be used to give explicit expressions for the counterterms in zero-dimensional QFTs using the lattice-Moebius function. Different applications for the tadpole-free quotient, in which all appearing elements correspond to semimodular lattices, are discussed.

  10. Operations space diagram for ECRH and ECCD

    DEFF Research Database (Denmark)

    Bindslev, H.

    2004-01-01

    A Clemmov-Mullaly-Allis (CMA) type diagram, the ECW-CMA diagram, for representing the operational possibilities of electron cyclotron heating and current drive (ECRH/ECCD) systems for fusion plasmas is presented. In this diagram, with normalized density and normalized magnetic field coordinates, the parameter range in which it is possible to achieve a given task (e.g. O-mode current drive for stabilizing a neoclassical tearing mode) appears as a region. With also the Greenwald density limit show...

  11. Nonparametric statistics of the quasar hubble diagrams

    International Nuclear Information System (INIS)

    A set of new, relatively general, and assumption-free statistical methods (described elsewhere) are used to derive information on the quasar luminosity function (LF) and distance-redshift relation from the optical and radio Hubble diagrams for 119 3CR and 4C quasars. The radio Hubble diagram is consistent with any distance-redshift relation, suggesting that there is no characteristic quasar radio luminosity. The optical Hubble diagram is consistent with three possibilities: (1)26 law

  12. A CNL for Contract-Oriented Diagrams

    OpenAIRE

    Camilleri, John J.; Paganelli, Gabriele; Schneider, Gerardo

    2014-01-01

    We present a first step towards a framework for defining and manipulating normative documents or contracts described as Contract-Oriented (C-O) Diagrams. These diagrams provide a visual representation for such texts, giving the possibility to express a signatory's obligations, permissions and prohibitions, with or without timing constraints, as well as the penalties resulting from the non-fulfilment of a contract. This work presents a CNL for verbalising C-O Diagrams, a web-...

  13. Bellows flow-induced vibrations

    Science.gov (United States)

    Tygielski, P. J.; Smyly, H. M.; Gerlach, C. R.

    1983-01-01

    The bellows flow excitation mechanism and results of comprehensive test program are summarized. The analytical model for predicting bellows flow induced stress is refined. The model includes the effects of an upstream elbow, arbitrary geometry, and multiple piles. A refined computer code for predicting flow induced stress is described which allows life prediction if a material S-N diagram is available.

  14. Determining the rheology of active lava flows from photogrammetric image sequence processing

    Science.gov (United States)

    James, M. R.; Robson, S.; Pinkerton, H.

    2010-12-01

    We describe a photogrammetric approach used to determine the rheological properties of active lava flows based on stereo image sequences. Bulk rheological properties can be estimated from measurements of flow slope, velocity and dimensions and so, at flow-fronts, they can be calculated from sequential digital elevation models (DEMs) acquired as the flow advances over new ground. For useful flow parameters to be extracted, DEMs may need to be obtained at approximately minute intervals, over durations of up to multiple hours. To deliver such data, we use oblique stereo pair sequences captured by digital SLR cameras and a semi-automated DEM-generation pipeline. Although similar data could be acquired with a terrestrial laser scanner, with deployments in remote and hazardous regions the photogrammetric approach offers significant logistical advantages in terms of reduced equipment cost, bulk, weight and power requirements. We describe the application of the technique to an active lava flow on Mount Etna, Sicily, in 2006. Image sequences were acquired from two tripod-mounted cameras over a period of ~3 hours, as the flow-front advanced ~15 m. Photogrammetric control was provided by 11 targets placed in the scene, with their coordinates determined by dGPS. The cameras were synchronised by a shutter release cable and triggered by an external timer (intervalometer). Image pairs were obtained every minute with DEMs extraction carried out on every fourth epoch; 57 DEMs, with a 0.25-m resolution, were generated. We describe the challenges associated with data collection in this remote environment and the techniques required to automate the photogrammetric analysis and sequence-DEM generation.

  15. The spectroscopic Hertzsprung-Russell diagram

    CERN Document Server

    Langer, N

    2014-01-01

    The Hertzsprung-Russell diagram is an essential diagnostic diagram for stellar structure and evolution, which has now been in use for more than 100 years. Our spectroscopic Hertzsprung-Russell (sHR) diagram shows the inverse of the flux-mean gravity versus the effective temperature. Observed stars whose spectra have been quantitatively analyzed can be entered in this diagram without the knowledge of the stellar distance or absolute brightness. Observed stars can be as conveniently compared to stellar evolution calculations in the sHR diagram as in the Hertzsprung-Russell diagram. However, at the same time, our ordinate is proportional to the stellar mass-to-luminosity ratio, which can thus be directly determined. For intermediate- and low-mass star evolution at constant mass, we show that the shape of an evolutionary track in the sHR diagram is identical to that in the Hertzsprung-Russell diagram. We also demonstrate that for hot stars, their stellar Eddington factor can be directly read off the sHR diagram. ...

  16. Digital image processing for quantification through full flow field tracing (FFFT) in narrow geometries at low Reynolds numbers

    Science.gov (United States)

    Braun, M. J.; Batur, C.; Karavelakis, G.

    1988-01-01

    This paper introduces a computer based image processing technique to the field of nonintrusive velocity measurements in fluid mechanics. The method is presented with two alternatives: the first is involving intense interaction between the operator and the computer system; the second is a first generation artificial intelligence based system, where a set of initially imputed rules replaces the operator. The methods are applied to flow in narrow gaps.

  17. Analyzing and modelling of flow transmission processes in river-systems with a focus on semi-arid conditions

    OpenAIRE

    Cunha Costa, Alexandre

    2012-01-01

    One of the major problems for the implementation of water resources planning and management in arid and semi-arid environments is the scarcity of hydrological data and, consequently, research studies. In this thesis, the hydrology of dryland river systems was analyzed and a semi-distributed hydrological model and a forecasting approach were developed for flow transmission processes in river-systems with a focus on semi-arid conditions. Three different sources of hydrological data (streamfl...

  18. Short range tracking of rainy clouds by multi-image flow processing of X-band radar data

    OpenAIRE

    Mesin Luca

    2011-01-01

    Abstract Two innovative algorithms for motion tracking and monitoring of rainy clouds from radar images are proposed. The methods are generalizations of classical optical flow techniques, including a production term (modelling formation, growth or depletion of clouds) in the model to be fit to the data. Multiple images are processed and different smoothness constraints are introduced. When applied to simulated maps (including additive noise up to 10 dB of SNR) showing formation and propagatio...

  19. Hazard Identification of the Offshore Three-phase Separation Process Based on Multilevel Flow Modeling and HAZOP

    DEFF Research Database (Denmark)

    Wu, Jing; Zhang, Laibin; Lind, Morten; Liang, Wei; Hu, Jinqiu; Jørgensen, Sten Bay; Sin, Gürkan; Khokhar, Zia Ullah

    2013-01-01

    HAZOP studies are widely accepted in chemical and petroleum industries as the method for conducting process hazard analysis related to design, maintenance and operation of the systems. Different tools have been developed to automate HAZOP studies. In this paper, a HAZOP reasoning method based on function-oriented modeling, Multilevel Flow Modeling (MFM), is extended with function roles. A graphical MFM editor, which is combined with the reasoning capabilities of the MFM Workbench developed by DT...

  20. Phase Diagram of Optimal Paths

    CERN Document Server

    Hansen, A; Hansen, Alex; Kertesz, Janos

    2004-01-01

    We show that choosing appropriate distributions of the randomness, the search for optimal paths links diverse problems of disordered media like directed percolation, invasion percolation, directed and non-directed spanning polymers. We also introduce a simple and efficient algorithm, which solves the d-dimensional model numerically in order N^(1+d_f/d) steps where d_f is the fractal dimension of the path. Using extensive simulations in two dimensions we identify the phase boundaries of the directed polymer universality class. A new strong-disorder phase occurs where the optimum paths are self-affine with parameter-dependent scaling exponents. Furthermore, the phase diagram contains directed and non-directed percolation as well as the directed random walk models at specific points and lines.