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Sample records for process flow diagram

  1. TEP process flow diagram

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-01-01

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

  2. 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

  3. 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...

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

    Directory of Open Access Journals (Sweden)

    Jane Hillston

    2009-10-01

    Full Text Available 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 quantitative models of concurrent biochemical reaction systems. We use this approach to compute the expected delay between input and output using deterministic and stochastic simulations of the MAPK signal transduction cascade. The scheme developed here is general and can be easily adapted to other output formalisms.

  5. Physiology Flow-Diagram Models

    Science.gov (United States)

    PhD Sandra J Bruner (Polk Community College Biology)

    2005-10-04

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

  6. Material flow of production process

    OpenAIRE

    Hanzelová Marcela

    2001-01-01

    This paper deals with material flow of the production process. We present the block diagram of material flow and capacities of engine in various plants each other. In this paper is used IPO (Input ? Process ? Output) diagram. IPO diagram described process with aspect to input and output. Production program regards string of precision, branch and paralel processes with aspect IPO diagram.Process is not important with aspect to events. We are looking on the process as a ?black box?. For process...

  7. 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.

  8. Software Tool Integrating Data Flow Diagrams and Petri Nets

    Science.gov (United States)

    Thronesbery, Carroll; Tavana, Madjid

    2010-01-01

    Data Flow Diagram - Petri Net (DFPN) is a software tool for analyzing other software to be developed. The full name of this program reflects its design, which combines the benefit of data-flow diagrams (which are typically favored by software analysts) with the power and precision of Petri-net models, without requiring specialized Petri-net training. (A Petri net is a particular type of directed graph, a description of which would exceed the scope of this article.) DFPN assists a software analyst in drawing and specifying a data-flow diagram, then translates the diagram into a Petri net, then enables graphical tracing of execution paths through the Petri net for verification, by the end user, of the properties of the software to be developed. In comparison with prior means of verifying the properties of software to be developed, DFPN makes verification by the end user more nearly certain, thereby making it easier to identify and correct misconceptions earlier in the development process, when correction is less expensive. After the verification by the end user, DFPN generates a printable system specification in the form of descriptions of processes and data.

  9. 18 CFR 260.8 - System flow diagrams: Format No. FERC 567.

    Science.gov (United States)

    2010-04-01

    ... 2010-04-01 false System flow diagrams: Format No. FERC 567. 260.8 ...SCHEDULES) § 260.8 System flow diagrams: Format No. FERC 567. (a...1 of each year five (5) copies of a diagram or diagrams reflecting...

  10. Photoelectronic complex for processing interference diagrams

    International Nuclear Information System (INIS)

    Structure of hardware and composition of algorithmically-programming complex part for interframe diagrams are described. Compelx includes microcomputer Elektronika-60, DBK-2, digitizer, videodata controller, buffer storage and is designed for operation with photoelectronic converter based on charged-coupled photosensitive IC. Preprocessing of interference diagrams involves resolving of maximum brightness of interference bands for data compaction in course of further electronic data processing. Raster size is 360x288 pixels (picture element), picture frame recording time - 20?s, pictorial data representation word length - 8, accuracy of maximum brightness location 1/2 of decomposition element

  11. Material flow of production process

    Directory of Open Access Journals (Sweden)

    Hanzelová Marcela

    2001-12-01

    Full Text Available This paper deals with material flow of the production process. We present the block diagram of material flow and capacities of engine in various plants each other. In this paper is used IPO (Input ? Process ? Output diagram. IPO diagram described process with aspect to input and output. Production program regards string of precision, branch and paralel processes with aspect IPO diagram.Process is not important with aspect to events. We are looking on the process as a ?black box?. For process is used different materials and raw materials. The foudation for material analysis is detailed model of production process with defined flow material, energy, waste etc.Material flow is organised move of mass (material, money, informations, people etc.. Material analysis is made against destination of material flow (i.e. from ending to beginning. Material analysis is performed on the detection demand of individual materials, stocks, forms, etc.For elementary materials and raw materials in which is based production program and which to create better part of production costs is mainly necessary to dedicate the remark. The fluency of material flow concentrates on the respect of the capacitive parameters for individual node from aspect to standardized qualitative parameters and allowed limits.

  12. Phase diagram calculations in materials processing

    International Nuclear Information System (INIS)

    The paper discusses the acquisition of thermodynamic data for materials processing and the mathematical methods used for checking the self-consistency of the data set. The information is stored in a relational database that was especially designed for phase diagram calculations. We present an algorithm for the systematic investigation of the excess Gibbs free energy of a ternary system as predicted by a large class of three-factor models in the sub-regular approximation. The techniques used to avoid the computational problems are discussed in the context of several selected oxide systems. (author)

  13. IGDS/TRAP Interface Program (ITIP). Software Design Document. [network flow diagrams for coal gasification studies

    Science.gov (United States)

    Jefferys, S.; Johnson, W.

    1981-01-01

    The preliminary design of the IGDS/TRAP Interface Program (ITIP) is described. The ITIP is implemented on the PDP 11/70 and interfaces directly with the Interactive Graphics Design System and the Data Management and Retrieval System. The program provides an efficient method for developing a network flow diagram. Performance requirements, operational rquirements, and design requirements are discussed along with sources and types of input and destination and types of output. Information processing functions and data base requirements are also covered.

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

    Science.gov (United States)

    Luzzatto-Fegiz, Paolo

    2011-11-01

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

  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. The Effect of Diagrams on Online Reading Processes and Memory

    Science.gov (United States)

    McCrudden, Matthew T.; Magliano, Joseph P.; Schraw, Gregory

    2011-01-01

    This work examined how adjunct displays influence college readers' moment-by-moment processing of text and the products of reading, using reading time (Experiments 1 & 2), and think-aloud methodologies (Experiment 3). Participants did or did not study a diagram before reading a text. Overall, the reading time data, think-aloud data, and recall…

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

    CERN Document Server

    Choi, C

    2004-01-01

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

  18. 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.

  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. Information Flow in the Launch Vehicle Design/Analysis Process

    Science.gov (United States)

    Humphries, W. R., Sr.; Holland, W.; Bishop, R.

    1999-01-01

    This paper describes the results of a team effort aimed at defining the information flow between disciplines at the Marshall Space Flight Center (MSFC) engaged in the design of space launch vehicles. The information flow is modeled at a first level and is described using three types of templates: an N x N diagram, discipline flow diagrams, and discipline task descriptions. It is intended to provide engineers with an understanding of the connections between what they do and where it fits in the overall design process of the project. It is also intended to provide design managers with a better understanding of information flow in the launch vehicle design cycle.

  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. Fluctuation diagrams for hot-wire anemometry in subsonic compressible flows

    Science.gov (United States)

    Stainback, P. C.; Nagabushana, K. A.

    1991-01-01

    The concept of using 'fluctuation diagrams' for describing basic fluctuations in compressible flows was reported by Kovasznay in the 1950's. The application of this technique, for the most part, was restricted to supersonic flows. Recently, Zinovev and Lebiga published reports where they considered the fluctuation diagrams in subsonic compressible flows. For the above studies, the velocity and density sensitivities of the heated wires were equal. However, there are considerable data, much taken in the 1950's, which indicate that under some conditions the velocity and density sensitivities are not equal in subsonic compressible flows. Therefore, possible fluctuation diagrams are described for the cases where the velocity and density sensitivities are equal and the more general cases where they are unequal.

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

    Science.gov (United States)

    de Oliveira, Marcelo Martins; Dickman, Ronald

    2014-09-01

    We study the two-species symbiotic contact process, recently proposed by de Oliveira, Santos, and Dickman [Phys. Rev. E 86, 011121 (2012)]. In this model, each site of a lattice may be vacant or host single individuals of species A and/or B. Individuals at sites with both species present interact in a symbiotic manner, having a reduced death rate ?diagram in the ?-? plane in one and two dimensions by means of exact numerical quasistationary distributions, cluster approximations, and Monte Carlo simulations. We also study the effects of asymmetric creation rates and diffusion of individuals. In two dimensions, for sufficiently strong symbiosis (i.e., small ?), the absorbing-state phase transition becomes discontinuous for diffusion rates D within a certain range. We report preliminary results on the critical surface and tricritical line in the ?-?-D space. Our results raise the possibility that strongly symbiotic associations of mobile species may be vulnerable to sudden extinction under increasingly adverse conditions. PMID:25314408

  4. 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.

  5. 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...

  6. Phase Diagram of Superconductors from Non-Perturbative Flow Equations

    OpenAIRE

    Bergerhoff, B.; Freire, F.; Litim, D.; Lola, S; Wetterich, C.(Institut für Theoretische Physik, Universität Heidelberg, Philosophenweg 16, D-69120 Heidelberg, Germany)

    1995-01-01

    The universal behaviour of superconductors near the phase transition is described by the three-dimensional field theory of scalar quantum electrodynamics. We approximately solve the model with the help of non-perturbative flow equations. A first- or second-order phase transition is found depending on the relative strength of the scalar versus the gauge coupling. The region of a second-order phase transition is governed by a fixed point of the flow equations with associated c...

  7. 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…

  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. Prediction of Forming Limit Diagrams for 22MnB5 in Hot Stamping Process

    Science.gov (United States)

    Li, Hongzhou; Wu, Xin; Li, Guangyao

    2013-08-01

    Hot stamping of ultra-high strength steels possesses many superior characteristics over conventional room temperature forming process and is fairly attractive in improving strength and reducing weight of vehicle body product. However, the mechanical and failure behavior of hot stamping boron steel 22MnB5 are both strongly affected by strain hardening, temperature, strain rate, and microstructure. In this paper, the material yield and flow behavior of 22MnB5 within the temperature and strain rate range of hot stamping are described by an advanced anisotropic yield criterion combined with two different hardening laws. The elevated temperature forming limit diagram (ET-FLD) is constructed using the M-K theoretical analysis. The developed model was validated by comparing our predicted result with experimental data in the literature under isothermal conditions. Based on the verified model, the influence of temperature and strain rate on the forming limit curve for 22MnB5 steel under equilibrium isothermal condition are discussed. Furthermore, the transient forming limit diagram is developed by performing a transient forming process simulation under non-isothermal transient condition.

  10. 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…

  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. Nonlinear energy transfers and phase diagrams for geostrophically balanced rotating--stratified flows

    CERN Document Server

    Herbert, Corentin

    2013-01-01

    Equilibrium statistical mechanics tools have been developed to obtain indications about the natural tendencies of nonlinear energy transfers in two-dimensional and quasi two-dimensional flows like rotating and stratified flows in geostrophic balance. In this article, we consider a simple model of such flows with a non-trivial vertical structure, namely two-layer quasi-geostrophic flows, which remain amenable to analytical study. We obtain the statistical equilibria of the system in the case of a linear vorticity-stream function relation, build the corresponding phase diagram, and discuss the most probable outcome of nonlinear energy transfers, both on the horizontal and on the vertical, in the presence of stratification and rotation.

  13. 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)

  14. 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...

  15. Dinosaur Extinction: Causal Loop Diagram of Earth Feedback System

    Science.gov (United States)

    Dewey M. McLean

    This site features a causal loop diagram from system dynamics methodology showing the solar-earth-space energy flow system (the dominant flow system driving earth's surficial systems, including the biosphere) and interactive natural earthly processes that influence it. Also included is a discussion of the diagram, and a link to a page that explains how to read causal loop diagrams.

  16. 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

  17. IGDS/TRAP Interface Program (ITIP). Software User Manual (SUM). [network flow diagrams for coal gasification studies

    Science.gov (United States)

    Jefferys, S.; Johnson, W.; Lewis, R.; Rich, R.

    1981-01-01

    This specification establishes the requirements, concepts, and preliminary design for a set of software known as the IGDS/TRAP Interface Program (ITIP). This software provides the capability to develop at an Interactive Graphics Design System (IGDS) design station process flow diagrams for use by the NASA Coal Gasification Task Team. In addition, ITIP will use the Data Management and Retrieval System (DMRS) to maintain a data base from which a properly formatted input file to the Time-Line and Resources Analysis Program (TRAP) can be extracted. This set of software will reside on the PDP-11/70 and will become the primary interface between the Coal Gasification Task Team and IGDS, DMRS, and TRAP. The user manual for the computer program is presented.

  18. Exploring the phase diagram of fully turbulent Taylor–Couette flow

    Science.gov (United States)

    Ostilla-Mónico, Rodolfo; van der Poel, Erwin P.; Verzicco, Roberto; Grossmann, Siegfried; Lohse, Detlef

    2014-12-01

    Direct numerical simulations of Taylor-Couette flow (TC). Shear Reynolds numbers of up to $3\\cdot10^5$, corresponding to Taylor numbers of $Ta=4.6\\cdot10^{10}$, were reached. Effective scaling laws for the torque are presented. The transition to the ultimate regime, in which asymptotic scaling laws (with logarithmic corrections) for the torque are expected to hold up to arbitrarily high driving, is analysed for different radius ratios $\\eta$, different aspect ratios $\\Gamma$ and different rotation ratios $Ro$. It is shown that the transition is approximately independent of $Ro$ and $\\Gamma$, but depends significantly on $\\eta$. We furthermore calculate the local angular velocity profiles and visualize different flow regimes that depend both on the shearing of the flow, and the Coriolis force originating from the outer cylinder rotation. Two main regimes are distinguished, based on the magnitude of the Coriolis force, namely the co-rotating and weakly counter-rotating regime dominated by Rayleigh-unstable regions, and the strongly counter-rotating regime where a mixture of stable and unstable regions exist. Furthermore, an analogy between $\\eta$ and outer-cylinder rotation is revealed, namely that smaller gaps behave like a wider gap with co-rotating cylinders, and that wider gaps behave like smaller gaps with weakly counter-rotating cylinders. Finally, the effect of $\\Gamma$ on the effective torque versus $Ta$ scaling is analysed and it is shown that different branches of the torque-versus-$Ta$ relationships associated to different aspect ratios are found to cross within $15%$ of the $Re$ associated to the transition to the ultimate regime. The paper culminates in phase diagram in the inner vs outer $Re$ number parameter space and in the $Ta$ vs $Ro$ parameter space, which can be seen as the extension of the Andereck \\emph{et al.} phase diagram towards the ultimate regime.

  19. 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.

  20. FMEF Electrical single line diagram and panel schedule verification process

    International Nuclear Information System (INIS)

    Since the FMEF did not have a mission, a formal drawing verification program was not developed, however, a verification process on essential electrical single line drawings and panel schedules was established to benefit the operations lock and tag program and to enhance the electrical safety culture of the facility. The purpose of this document is to provide a basis by which future landlords and cognizant personnel can understand the degree of verification performed on the electrical single lines and panel schedules. It is the intent that this document be revised or replaced by a more formal requirements document if a mission is identified for the FMEF

  1. 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.

  2. High-energy, large-momentum-transfer processes: Ladder diagrams in ?3 theory. Pt. 1

    International Nuclear Information System (INIS)

    Relativistic quantum field theories may give us useful guidance to understanding high-energy, large-momentum-transfer processes, where the center-of-mass energy is much larger than the transverse momentum transfers, which are in turn much larger than the masses of the participating particles. With this possibility in mind, we study the ladder diagrams in ?3 theory. In this paper, some of the necessary techniques are developed and applied to the simplest cases of the fourth- and sixth-order ladder diagrams. (orig.)

  3. High-energy, large-momentum-transfer processes: Ladder diagrams in var-phi 3 theory

    International Nuclear Information System (INIS)

    Relativistic quantum field theories may help one to understand high-energy, large-momentum-transfer processes, where the center-of-mass energy is much larger than the transverse momentum transfers, which are in turn much larger than the masses of the participating particles. With this possibility in mind, the author studies ladder diagrams in var-phi 3 theory. He shows that in the limit s much-gt |t| much-gt m2, the scattering amplitude for the N-rung ladder diagram takes the form s-1|t|-N+1 times a homogeneous polynomial of degree 2N - 2 and ln s and ln |t|. This polynomial takes different forms depending on the relation of ln |t| to ln s. More precisely, the asymptotic formula for the N-rung ladder diagram has points of non-analytically when ln |t| = ? ln s for ? = 1/2, 1/3, hor-ellipsis, 1/N-2

  4. Support system for process flow scheduling

    OpenAIRE

    Salomone, Enrique; Chiotti, Omar Juan Alfredo; Lerch, Juan

    2001-01-01

    Process flow scheduling is a concept that refers to the scheduling of flow shop process plants, whose scheduling calculations are guided by the process structure. In a wide variety of high-volume process industries, the process flow scheduling concept implies an integrated structure for planning and scheduling. This integrated vision of the planning function and the very particular characteristics of the process industry production environment challenge the application of the most traditio...

  5. Padé approximants, optimal renormalization scales, and momentum flow in Feynman diagrams

    CERN Document Server

    Brodsky, S J; Gardi, E; Karliner, M M; Samuel, Mark A; Brodsky, Stanley J.; Ellis, John; Gardi, Einan; Karliner, Marek; Samuel, Mark. A.

    1997-01-01

    We show that the Padé Approximant (PA) approach for resummation of perturbative series in QCD provides a systematic method for approximating the flow of momentum in Feynman diagrams. In the large-$\\beta_0$ limit, diagonal PA's generalize the Brodsky-Lepage-Mackenzie (BLM) scale-setting method to higher orders in a renormalization scale- and scheme-invariant manner, using multiple scales that represent Neubert's concept of the distribution of momentum flow through a virtual gluon. If the distribution is non-negative, the PA's have only real roots, and approximate the distribution function by a sum of delta-functions, whose locations and weights are identical to the optimal choice provided by the Gaussian quadrature method for numerical integration. We show how the first few coefficients in a perturbative series can set rigorous bounds on the all-order momentum distribution function, if it is positive. We illustrate the method with the vacuum polarization function and the Bjorken sum rule computed in the large...

  6. Padacute e approximants, optimal renormalization scales, and momentum flow in Feynman diagrams

    International Nuclear Information System (INIS)

    We show that the Padacute e approximant (PA) approach for resummation of perturbative series in QCD provides a systematic method for approximating the flow of momentum in Feynman diagrams. In the large-?0 limit, diagonal PA close-quote s generalize the Brodsky-Lepage-Mackenzie (BLM) scale-setting method to higher orders in a renormalization scale- and scheme-invariant manner, using multiple scales that represent Neubert close-quote s concept of the distribution of momentum flow through a virtual gluon. If the distribution is non-negative, the PA close-quote s have only real roots, and approximate the distribution function by a sum of ? functions, whose locations and weights are identical to the optimal choice provided by the Gaussian quadrature method for numerical integration. We show how the first few coefficients in a perturbative series can set rigorous bounds on the all-order momentum distribution function, if it is positive. We illustrate the method with the vacuum polarization function and the Bjorken sum rule computed in the large-?0 limit. copyright 1997 The American Physical Society

  7. Padé approximants, optimal renormalization scales, and momentum flow in Feynman diagrams

    Science.gov (United States)

    Brodsky, Stanley J.; Ellis, John; Gardi, Einan; Karliner, Marek; Samuel, Mark A.

    1997-12-01

    We show that the Padé approximant (PA) approach for resummation of perturbative series in QCD provides a systematic method for approximating the flow of momentum in Feynman diagrams. In the large-?0 limit, diagonal PA's generalize the Brodsky-Lepage-Mackenzie (BLM) scale-setting method to higher orders in a renormalization scale- and scheme-invariant manner, using multiple scales that represent Neubert's concept of the distribution of momentum flow through a virtual gluon. If the distribution is non-negative, the PA's have only real roots, and approximate the distribution function by a sum of ? functions, whose locations and weights are identical to the optimal choice provided by the Gaussian quadrature method for numerical integration. We show how the first few coefficients in a perturbative series can set rigorous bounds on the all-order momentum distribution function, if it is positive. We illustrate the method with the vacuum polarization function and the Bjorken sum rule computed in the large-?0 limit.

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

    OpenAIRE

    Sevilay Karamustafao?lu

    2011-01-01

    This study was carried out to identify the level of Science and Technology student teachers’ science processskills and to determine how efficient I diagrams are in developing these skills. The corpus of the study wasconsisted of 40 science and technology student teachers who were having Instructional Technologies andMaterial Design course during the 2009-10 academic years at Amasya University, Faculty of Education. Thestudy was conducted as a basic experimental design. A science process ski...

  9. UO2 flow freezing processes

    International Nuclear Information System (INIS)

    Transient freezing of molten UO2 and UO2-steel mixtures in steel channels is an important functional heat transfer process which occurs in the course of Liquid Metal-Cooled Fast Breeder Reactor (LMFBR) Hypothetical Core Disruptive Accidents (HCDA). Fuel freezing processes can influence both the transient overpower (TOP) and transient undercooling (TUC) accidents. In the absence of freezing, either fuel sweepout or continuous fuel removal can lead to shutdown with a largely coolable geometry in the TOP case and greatly reduce concerns over recriticality in the TUC case. However, with fuel freezing either case may lead to a temporarily ''bottled-up core'' condition which is relieved by melting of the initially formed plugs. Whether further freezing occurs in either the upward or downward direction through the core support structure is of interest in determining the decay heat level for Post-Accident Heat Removal (PAHR). Attention is focused on the freezing of ceramic fuel in steel channels. A discussion of the conduction-controlled and bulk freezing mechanisms is given first. A fuel crust stability criterion is proposed, and an explicit formula providing a rough estimate of critical fuel crust disintegration conditions is developed. A comparison of the crust stability criterion with a number of explanatory experimental results is made. A steel ablation-fuel freezing mechanism is identified. If the conditions in the fuel flow are such to prevent fues in the fuel flow are such to prevent fuel crust growth, then the steel wall melting can become catastrophic. Steel ablation rapidly leads to fuel freezing in a bulk manner via turbulent mixing between the relatively ''cold'' molten steel and hot molten fuel. Based on this ablation-freezing concept, simple equations are developed for molten fuel penetration into steel channels. Comparison of the equations with the available experimental results proves favorable

  10. 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

  11. Global Bifurcation Diagram for the Kerner-Konhäuser Traffic Flow Model

    Science.gov (United States)

    Delgado, Joaquín; Saavedra, Patricia

    We study traveling wave solutions of the Kerner-Konhäuser PDE for traffic flow. By a standard change of variables, the problem is reduced to a dynamical system in the plane with three parameters. In a previous paper [Carrillo et al., 2010] it was shown that under general hypotheses on the fundamental diagram, the dynamical system has a surface of critical points showing either a fold or cusp catastrophe when projected under a two-dimensional plane of parameters named qg-vg. In either case, a one parameter family of Takens-Bogdanov (TB) bifurcation takes place, and therefore local families of Hopf and homoclinic bifurcation arising from each TB point exist. Here, we prove the existence of a degenerate Takens-Bogdanov bifurcation (DTB) which in turn implies the existence of Generalized Hopf or Bautin bifurcations (GH). We describe numerically the global lines of bifurcations continued from the local ones, inside a cuspidal region of the parameter space. In particular, we compute the first Lyapunov exponent, and compare with the GH bifurcation curve. We present some families of stable limit cycles which are taken as initial conditions in the PDE leading to stable traveling waves.

  12. Potential - oxoacidity diagrams for electrochemical processing of actinides in molten-salt

    International Nuclear Information System (INIS)

    Molten-salt based pyroprocessing of nuclear fuels, especially metallic fuels is being considered as a more effective method compared to wet processing route. Lithium and potassium chloride eutectic is one of the most investigated molten salt electrolyte for this purpose. Due to difference in the reduction potential of actinides, rare-earths and other fission products, actinides can be easily separated from other fission product during electrolytic pyroprocessing. However, due to close reduction potentials of actinide species Th, U, Pu, Am, Cm, their separation needs closer investigation of controlling parameters, pO2- and voltage. Therefore, potential-oxoacidity diagrams of these species were calculated in LiCL-KCI eutectic electrolyte at 743 K, with reference to Cl2(1 atm)/Cl- electrode. These diagrams helped in estimating the required oxygen potentials and voltages to selectively reduce different species of actinides to their metallic forms. (author)

  13. Magnetic phase diagram and demagnetization processes in perpendicular exchange-spring multilayers

    Science.gov (United States)

    Asti, G.; Ghidini, M.; Pellicelli, R.; Pernechele, C.; Solzi, M.; Albertini, F.; Casoli, F.; Fabbrici, S.; Pareti, L.

    2006-03-01

    The magnetic behavior of the perpendicular exchange-spring bilayer and multilayer, constituted of a hard and a soft phase that are exchange-coupled on a nanometric scale, is analyzed by a one-dimensional micromagnetic model leading to a complete magnetic phase diagram in terms of layer thicknesses. The validity of the one-dimensional assumption for the perpendicular situation is demonstrated. The phase diagram provides information on the type of demagnetization processes and the critical fields at which nucleation and reversal take place, depending on the intrinsic properties of the chosen soft and hard materials. An analytical expression of the reversal field is deduced for relatively large thicknesses. Moreover, the effect of a reduced interlayer coupling is also taken into account, leading to slight modifications of both the magnetic phase diagram and the hysteresis loops. A series of Fe/FePt bilayers, prepared by sputtering, has been used to evaluate the predictions of the model, which has also been tested with the available literature data on FeRh/FePt bilayers. Both systems have a particular relevance for potential applications in magnetic recording as well as magnetic microelectromechanical systems.

  14. Effect of strong correlation on the study of renormalization group flow diagram for Kondo effect in a interacting quantum wire

    OpenAIRE

    Sarkar, Sujit

    2008-01-01

    We present the study of Kondo effect in an interacting quantum wire. We mainly emphasis the effect of strong electronic correlations in the study of renormalization group flow diagram and the stability analysis of fixed points for both magnetic and nonmagnetic impurities. We observe that the behavior of the system is either in the single channel or in the two channel Kondo effect depending on the initial values of coupling constants and strong correlations.

  15. 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

  16. ALGAE REMOVAL BY THE OVERLAND FLOW PROCESS

    Science.gov (United States)

    Control of algae production will be necessary when lagoons are utilized as a preapplication treatment process for overland flow. The overland flow process has a surface discharge and must meet secondary treatment limitations to be viable. Brief summaries of other algae removal in...

  17. 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.

  18. Causal Loop Diagram (CLD As an Instrument for Strategic Planning Process: American University of Nigeria, Yola

    Directory of Open Access Journals (Sweden)

    Apollos bitrus Goyol

    2013-12-01

    Full Text Available American University of Nigeria (AUN, was established in 2005 and has emerged as Nigeria’s most preferreduniversity. Located in Yola, Adamawa State, North-eastern Nigeria, the university was conceived in response tothe need for a world-class university in sub-Saharan Africa. The university offers an American-style educationmodeled after the curriculum of American universities with corresponding approaches to teaching and assessingstudents. Nigeria with a population of over 160 million. It is estimated that 3 million students graduate fromhigh schools every year. With 124 universities with less than 1million enrollment spaces. The implication is thatthere is a serious shortfall in the number of students that wants to further their education. With this prevailingsituation every university must do everything possible to provide prospective students with placement.Therefore, the main objective of this study is to take a critical look at the possible ways that the university canstrategically adopt to attract this huge number of high school graduates using the Casual Loop Diagram (CLDfor identifying, managing and utilizing Critical Performance Indicators (CPIs in tackling existing problemsthrough coordinated partnership and collaboration towards appropriate policy recommendations. The mostuseful tool for identifying the causes of problems is a cause-and-effect diagram, also known as a Fishbone orIshikawa diagram which is very similar to the CLD. The results of the survey that was administered to aconvenient random sample of AUN students (N=369. The results indicated that a large percentage believes thatthe university has a very good prospect of achieving its set goals as a development university if the standardsand institutional characteristics can be sustained and improved upon. To better understand the KPI in relation tothe results, the Casual Loop Diagram (CLD was used to analysis the relationships between the results the KPI.This would assist in better approach in the recruitment process.Given that this is a pilot study, the results are only preliminary and merely indicate how to improve policy andprogram decisions especially for AUN as a development university. The short time outcome and impact of thestudy has provided some insight into the college choice process of choosing a college using the CLD. Also it isimportant for admission professionals understand the factors that shape the college decision-making process andthe stages students move through as they make decisions.The flexibility of the design allows for adaptation to any institution’s unique structure and mission.

  19. Fluid flow processes at basin scale

    OpenAIRE

    Bitzer, Klaus; Trave? I Herrero, Anna; Carmona Pe?rez, Jose? Ma

    2001-01-01

    S u b s u r face fluid flow plays a significant role in many geologic processes and is increasingly being studied in the scale of sedimentary basins and geologic time perspective. Many economic resources such as petroleum and mineral deposits are products of basin scale fluid flow operating over large periods of time. Such ancient flow systems can be studied through analysis of diagenetic alterations and fluid inclusions to constrain physical and chemical conditions of fluids and rocks during...

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

    Science.gov (United States)

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

    2014-06-01

    Ring-diagram analysis of acoustic waves observed at the photosphere provides in principle 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-analysis has focused on regions of extent ~15 deg (200 Mm) or more in order to provide reasonable mode sets for inversions. The HMI analysis pipeline however 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 disc, not all well-understood. In this study we characterize those systematic effects with higher spatial resolution. This enable us to remove them more effectively as we map the temporal and spatial evolution of the flows, leaving open the question of their mean structure which is most affected by the systematics. We present results for the ring-diagram determination of the flow anomalies corresponding to the torsional oscillation pattern in differential rotation and analogous patterns in the meridional cell structure over the early part of the current solar cycle observed by HMI.

  1. 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

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

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

  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. Global bifurcation diagram for the Kerner-Konhauser traffic flow model

    OpenAIRE

    Delgado, Joaquin; Saavedra, Patricia

    2013-01-01

    We study traveling wave solutions of the Kerner--Konh\\"auser PDE for traffic flow. By a standard change of variables, the problem is reduced to a dynamical system in the plane with three parameters. In a previous paper (Carrillo, F.A., J. Delgado, P. Saavedra, R.M. Velasco and F. Verduzco, (2013). Traveling waves, catastrophes and bifurcations in a generic second order traffic flow model --to appear in \\textit{International Journal of Bifurcation and Chaos}--, it was shown t...

  6. Top-down versus bottom-up processing of influence diagrams in probabilistic analysis

    International Nuclear Information System (INIS)

    Recent work by Phillips et al., and Selby et al., has shown that influence diagram methodology can be a useful analytical tool in reactor safety studies. An influence diagram is a graphical representation of probabilistic dependence within a system or event sequence. Bayesian statistics are employed to transform the relationships depicted in the influence diagram into the correct expression for a desired marginal probability (e.g. the top event). As with fault trees, top-down and bottom-up algorithms have emerged as the dominant methods for quantifying influence diagrams. Purpose of this paper is to demonstrate a potential error in employing the bottom-up algorithm when dealing with interdependencies. In addition, the computing efficiency of both methods is discussed

  7. Top-down versus bottom-up processing of influence diagrams in probabilistic analysis

    International Nuclear Information System (INIS)

    Recent work by Phillips and Selby has shown that influence diagram methodology can be a useful analytical tool in reactor safety studies. In some instances an influence diagram can be used as a graphical representation of probabilistic dependence within a system or event sequence. Under these circumstances, Bayesian statistics is employed to transform the relationships depicted in the influence diagram into the correct expression for a desired marginal probability (e.g. the top node). Top-down and bottom-up algorithms have emerged as the dominant methods for quantifying influence diagrams. The purpose of this paper is to demonstrate a potential error in employing the bottom-up algorithm when dealing with interdependencies

  8. 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.

  9. Top-down versus bottom-up processing of influence diagrams in probabilistic analysis

    International Nuclear Information System (INIS)

    Recent work by Phillips et al and Selby et al has shown that influence diagram methodology can be a useful analytical tool in reactor safety studies. In some instances, an influence diagram can be used as a graphical representation of probabilistic dependence within a system or event sequence. Under these circumstances, Bayesian statistics is employed to transform the relationships depicted in the influence diagram into the correct expression for a desired marginal probability (e.g., the top node). In the references cited above, the authors demonstrated the usefulness of influence diagrams for assessing the reliability of operator performance during pressurized thermal shock transients. In addition, the use of influence diagrams identified the critical variables that had the greatest impact on operator reliability for a particular scenario (e.g., control room design, procedures, etc.). Top-down and bottom-up algorithms have emerged as the dominant methods for quantifying influence diagrams. The purpose of this paper is to demonstrate a potential error in employing the bottom-up algorithm when dealing with interdependencies

  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. 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...

  12. Improving the Functional Diagnostic Process using Dynamic Master Logic Diagram (DMLD) Modeling Strategy

    International Nuclear Information System (INIS)

    In recent years, state based functional diagnostic systems have gained a growing attention among the model based diagnostic systems. They have been used to diagnose the new faults of the complex systems. On the other hand, a main point considered against it is its subjective, and the inability of reusing the knowledge gathered from one engineer by others. Different methods have been' suggested to solve these problems. In the same way, the suggested functional diagnostic system introduces the uses of Dynamic Master Logic Diagram (DMLD) modeling strategy for the functional diagnostic systems. DMLD has proven its power as a good modeling strategy. It can model the functions of the system's components in terms of a set of defined primitives for the domain of applications. However, the suggested system can use the DMLD technique to model the small functions of the system according to the defined primitives of its domain. So, the modeling process of the system is relatively invariant from one modeler to another. Also, the functions defined can be reused by other users in the domain for solving different problems. Besides, it can deal with the complex system in a flexible manner. Thus, the proposed system can improve the performance of the state based functional diagnostic systems. It can be applied for a wide area of the complex systems. It has been applied for a fluid system as a case of the real-time systems. The suggested system has proved its success as a powerful practhas proved its success as a powerful practical state based functional diagnostic system

  13. Stereo Diagrams

    Science.gov (United States)

    Dexter Perkins

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

  14. Projection of postgraduate students flow with a smoothing matrix transition diagram of Markov chain

    Science.gov (United States)

    Rahim, Rahela; Ibrahim, Haslinda; Adnan, Farah Adibah

    2013-04-01

    This paper presents a case study of modeling postgraduate students flow at the College of Art and Sciences, Universiti Utara Malaysia. First, full time postgraduate students and the semester they were in are identified. Then administrative data were used to estimate the transitions between these semesters for the year 2001-2005 periods. Markov chain model is developed to calculate the -5 and -10 years projection of postgraduate students flow at the college. The optimization question addressed in this study is 'Which transitions would sustain the desired structure in the dynamic situation such as trend towards graduation?' The smoothed transition probabilities are proposed to estimate the transition probabilities matrix of 16 × 16. The results shows that using smoothed transition probabilities, the projection number of postgraduate students enrolled in the respective semesters are closer to actual than using the conventional steady states transition probabilities.

  15. Exploring the phase diagram of fully turbulent Taylor-Couette flow

    OpenAIRE

    Mo?nico, Rodolfo Ostilla; Poel, Erwin P.; Verzicco, Roberto; Grossmann, Siegfried; Lohse, Detlef

    2014-01-01

    Direct numerical simulations of Taylor-Couette flow (TC). Shear Reynolds numbers of up to $3\\cdot10^5$, corresponding to Taylor numbers of $Ta=4.6\\cdot10^{10}$, were reached. Effective scaling laws for the torque are presented. The transition to the ultimate regime, in which asymptotic scaling laws (with logarithmic corrections) for the torque are expected to hold up to arbitrarily high driving, is analysed for different radius ratios $\\eta$, different aspect ratios $\\Gamma$...

  16. The Art of Sorting: Using Venn Diagrams To Learn Science Process Skills.

    Science.gov (United States)

    Moore, Jan E.

    2003-01-01

    Presents activities that have been proven to teach young learners to sort and classify objects that contain more than one attribute. The activities require that students employ the use of sorting hoops and attribute blocks to create Venn diagrams, the assembly of which requires practice. Includes cross-curricular uses of these learning tools.…

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

    OpenAIRE

    Miroslav Grgec; Robert Mužar

    2007-01-01

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

  18. Work flow in process development for energy efficient processes

    International Nuclear Information System (INIS)

    Increasing expenditures for energy require an optimization of chemical processes with regard to energy efficiency. Energy efficiency is of course only one aspect of a multi-objective optimization during process development. It will be shown how methods for increasing energy efficiency are integrated in the workflow of BASF's process development for new and existing processes. Special focus will be on the use of exergy analysis and its high relevance to industrial chemical processes. It will be shown how exergy analysis might be used for comparison of different process concepts. Additionally examples will emphasize how an increase of energy efficiency by change of operational conditions can be reached. Also these measures can be interpreted in terms of reduced exergy losses. For all examples the additional investment, if needed, is justified by the savings, which were altogether approximately 7 million euro per year. Highlights: ? Work flow for development of energy efficient processes for new and existing plants in the chemical industry is presented. ? Exergy analysis has been used to identify favorable process concepts. ? Examples with annual savings of about 7 million euro emphasize the use of the method.

  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. Flow processes in a radiant tube burner: Combusting flow

    International Nuclear Information System (INIS)

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

  1. 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

  2. Seasonal changes of the quantitative importance of protozoans in a large lake : an ecosystem approach using mass-balanced carbon flow diagrams

    OpenAIRE

    Gaedke, Ursula; Straile, Dietmar

    1994-01-01

    Based on comprehensive measurements of plankton abundance and production, quantitative carbon flow diagrams were established for the pelagic community of a large lake (L. Constance) for ten successive time intervals during the seasonal course of 1987. Using reasonable diet compositions and parameters (e.g. trophic transfer efficiencies in the range of l0-35%), mass-balance conditions could be fulfilled for individual compartments and the entire food web, provided that ciliate growth rates use...

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

    Science.gov (United States)

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

    2015-03-01

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

  4. 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...

  5. The operad of temporal wiring diagrams: formalizing a graphical language for discrete-time processes

    OpenAIRE

    Rupel, Dylan; Spivak, David I.

    2013-01-01

    We investigate the hierarchical structure of processes using the mathematical theory of operads. Information or material enters a given process as a stream of inputs, and the process converts it to a stream of outputs. Output streams can then be supplied to other processes in an organized manner, and the resulting system of interconnected processes can itself be considered a macro process. To model the inherent structure in this kind of system, we define an operad $\\mathcal{...

  6. Automatic Test case Generation from UML Activity Diagrams

    OpenAIRE

    V.Mary Sumalatha*1; Dr G.S.V.P.Raju2

    2014-01-01

    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 pro...

  7. Hanford Site Treated Effluent Disposal Facility process flow sheet

    International Nuclear Information System (INIS)

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

  8. Venn Diagrams

    Science.gov (United States)

    2011-05-24

    In this activity, students are given a Venn diagram with certain rules and an element. They must then determine where in the Venn diagram the element belongs. This activity allows students to practice placing elements in Venn diagrams as well as reviewing mathematical terms associated with the different rules. This activity includes supplemental materials, including background information about the topics covered, a description of how to use the application, and exploration questions for use with the java applet.

  9. Carroll Diagrams

    Science.gov (United States)

    NRICH team

    2012-01-01

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

  10. Correlation between viscous-flow activation energy and phase diagram in four systems of Cu-based alloys

    International Nuclear Information System (INIS)

    Activation energy is obtained from temperature dependence of viscosities by means of a fitting to the Arrhenius equation for liquid alloys of Cu-Sb, Cu-Te, Cu-Sn and Cu-Ag systems. We found that the changing trend of activation energy curves with concentration is similar to that of liquidus in the phase diagrams. Moreover, a maximum value of activation energy is in the composition range of the intermetallic phases and a minimum value of activation energy is located at the eutectic point. The correlation between the activation energy and the phase diagrams has been further discussed.

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

    OpenAIRE

    Mohammed Khennich; Mikhail Sorin; Nicolas Galanis

    2014-01-01

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

  12. 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

  13. Process flow measurement based on tracer techniques

    International Nuclear Information System (INIS)

    Flow measurement methods based on the tracer techniques are the transit time method as well as methods based on tracer dilution. These methods can be applied to the on-site calibration of flowmeters and to measuring the flowrate where no flowmeter is installed. The accuracy of the tracer methods depends on the prevailing measuring conditions. In this report the accuracy of the transit time method under field conditions is estimated to be 1-2% on the 99,7% confidence level. The accuracy of the isotope dilution method is estimated as slightly better, namely about 0.5% at its best. An even better accuracy, about 0.2%, could be achieved by developing the method and the measuring equipment. Tests were carried out with the transit time method for water and steam flow. While measuring water flow the effect of different measuring parameters upon the repeatability of the method were looked into. Such were the number of the detectors and the distance between the measuring points. Different means of tracer injection were tested, as well. These had less effect than expected. The accuracies achieved in steam flow measurements were of the same order of magnitude as in water flow measurements. The tracers used were 137mBa for water flow and 41Ar for steam flow measurements

  14. 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.

  15. Phase diagrams

    International Nuclear Information System (INIS)

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

  16. Phase Diagrams

    Science.gov (United States)

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

  17. Comparison of microstructural evolution associated with the stress-strain diagrams for nickel and 304 stainless steel: an electron microscope study of microyielding and plastic flow

    International Nuclear Information System (INIS)

    The microstructures attendant to specific peak strains along the strain axis of the stress-strain diagram for type 304-stainless steel and nickel have been examined and compared by transmission electron microscopy from epsilon = 0.05% to epsilon 55% in the former and from epsilon = 0.05% to epsilon = 35% in the latter. The onset of flow is characterised by the emission of dislocations from grain boundary ledge sources which form emission profiles resembling dislocation pile-ups in the stainless steel, and a random distribution of dislocations with evidence for very short emission profiles near the grain boundaries in nickel. The results are presented and discussed. (author)

  18. 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

  19. Ultrasonic flow measurements for irrigation process monitoring

    Science.gov (United States)

    Ziani, Elmostafa; Bennouna, Mustapha; Boissier, Raymond

    2004-02-01

    This paper presents the state of the art of the general principle of liquid flow measurements by ultrasonic method, and problems of flow measurements. We present an ultrasonic flowmeter designed according to smart sensors concept, for the measurement of irrigation water flowing through pipelines or open channels, using the ultrasonic transit time approach. The new flowmeter works on the principle of measuring time delay differences between sound pulses transmitted upstream and downstream in the flowing liquid. The speed of sound in the flowing medium is eliminated as a variable because the flowrate calculations are based on the reciprocals of the transmission times. The transit time difference is digitally measured by means of a suitable, microprocessor controlled logic. This type of ultrasonic flowmeter will be widely used in industry and water management, it is well studied in this work, followed by some experimental results. For pressurized channels, we use one pair of ultrasonic transducer arranged in proper positions and directions of the pipe, in this case, to determine the liquid velocity, a real time on-line analysis taking account the geometries of the hydraulic system, is applied to the obtained ultrasonic data. In the open channels, we use a single or two pairs of ultrasonic emitter-receiver according to the desired performances. Finally, the goals of this work consist in integrating the smart sensor into irrigation systems monitoring in order to evaluate potential advantages and demonstrate their performance, on the other hand, to understand and use ultrasonic approach for determining flow characteristics and improving flow measurements by reducing errors caused by disturbances of the flow profiles.

  20. 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

  1. 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.

  2. Separation of hydrogen isotopes by a flowing bed process

    International Nuclear Information System (INIS)

    Results of an experimental study on a flowing bed process for continuous hydrogen isotope separation are presented. Separation performance was low with a 25% by weight palladium on alumina adsorbent, resulting in a high tritium inventory. In addition, significant breakdown of the solid adsorbent occurred as it recirculated through the process equipment and the product streams were contaminated by the adsorbent carrier gas. Due to these problems, this flowing bed process is predicted to be uneconomic for a full scale plant

  3. Phase Diagrams in Vivo

    Science.gov (United States)

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

  4. Hovmoller Diagrams

    Science.gov (United States)

    Hovmoller diagrams are great for displaying large amounts of data in a meaningful and understandable form. The image on the left graphical shows the El Nino signal in the equatorial Pacific (100 W to 140 E ...

  5. Documentation of a Conduit Flow Process (CFP) for MODFLOW-2005

    Science.gov (United States)

    Shoemaker, W. Barclay; Kuniansky, Eve L.; Birk, Steffen; Bauer, Sebastian; Swain, Eric D.

    2007-01-01

    This report documents the Conduit Flow Process (CFP) for the modular finite-difference ground-water flow model, MODFLOW-2005. The CFP has the ability to simulate turbulent ground-water flow conditions by: (1) coupling the traditional ground-water flow equation with formulations for a discrete network of cylindrical pipes (Mode 1), (2) inserting a high-conductivity flow layer that can switch between laminar and turbulent flow (Mode 2), or (3) simultaneously coupling a discrete pipe network while inserting a high-conductivity flow layer that can switch between laminar and turbulent flow (Mode 3). Conduit flow pipes (Mode 1) may represent dissolution or biological burrowing features in carbonate aquifers, voids in fractured rock, and (or) lava tubes in basaltic aquifers and can be fully or partially saturated under laminar or turbulent flow conditions. Preferential flow layers (Mode 2) may represent: (1) a porous media where turbulent flow is suspected to occur under the observed hydraulic gradients; (2) a single secondary porosity subsurface feature, such as a well-defined laterally extensive underground cave; or (3) a horizontal preferential flow layer consisting of many interconnected voids. In this second case, the input data are effective parameters, such as a very high hydraulic conductivity, representing multiple features. Data preparation is more complex for CFP Mode 1 (CFPM1) than for CFP Mode 2 (CFPM2). Specifically for CFPM1, conduit pipe locations, lengths, diameters, tortuosity, internal roughness, critical Reynolds numbers (NRe), and exchange conductances are required. CFPM1, however, solves the pipe network equations in a matrix that is independent of the porous media equation matrix, which may mitigate numerical instability associated with solution of dual flow components within the same matrix. CFPM2 requires less hydraulic information and knowledge about the specific location and hydraulic properties of conduits, and turbulent flow is approximated by modifying horizontal conductances assembled by the Block-Centered Flow (BCF), Layer-Property Flow (LPF), or Hydrogeologic-Unit Flow Packages (HUF) of MODFLOW-2005. For both conduit flow pipes (CFPM1) and preferential flow layers (CFPM2), critical Reynolds numbers are used to determine if flow is laminar or turbulent. Due to conservation of momentum, flow in a laminar state tends to remain laminar and flow in a turbulent state tends to remain turbulent. This delayed transition between laminar and turbulent flow is introduced in the CFP, which provides an additional benefit of facilitating convergence of the computer algorithm during iterations of transient simulations. Specifically, the user can specify a higher critical Reynolds number to determine when laminar flow within a pipe converts to turbulent flow, and a lower critical Reynolds number for determining when a pipe with turbulent flow switches to laminar flow. With CFPM1, the Hagen-Poiseuille equation is used for laminar flow conditions and the Darcy-Weisbach equation is applied to turbulent flow conditions. With CFPM2, turbulent flow is approximated by reducing the laminar hydraulic conductivity by a nonlinear function of the Reynolds number, once the critical head difference is exceeded. This adjustment approximates the reductions in mean velocity under turbulent ground-water flow conditions.

  6. 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.

  7. 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.

  8. Simulation of Flow Fluid in the BOF Steelmaking Process

    Science.gov (United States)

    Lv, Ming; Zhu, Rong; Guo, Ya-Guang; Wang, Yong-Wei

    2013-12-01

    The basic oxygen furnace (BOF) smelting process consists of different chemical reactions among oxygen, slag, and molten steel, which engenders a vigorous stirring process to promote slagging, dephosphorization, decarbonization, heating of molten steel, and homogenization of steel composition and temperature. Therefore, the oxygen flow rate, lance height, and slag thickness vary during the smelting process. This simulation demonstrated a three-dimensional mathematical model for a 100 t converter applying four-hole supersonic oxygen lance and simulated the effect of oxygen flow rate, lance height, and slag thickness on the flow of molten bath. It is found that as the oxygen flow rate increases, the impact area and depth increases, which increases the flow speed in the molten bath and decreases the area of dead zone. Low oxygen lance height benefits the increase of impact depth and accelerates the flow speed of liquid steel on the surface of the bath, while high oxygen lance height benefits the increase of impact area, thereafter enhances the uniform distribution of radial velocity in the molten steel and increases the flow velocity of molten steel at the bottom of furnace hearth. As the slag thickness increases, the diameter of impinging cavity on the slag and steel surface decreases. The radial velocity of liquid steel in the molten bath is well distributed when the jet flow impact on the slag layer increases.

  9. Knowledge Representation and Communication: Imparting Current State Information Flow to CPR Stakeholders

    OpenAIRE

    La Cruz, Norberto B.; Spiece, Leslie J.

    2000-01-01

    Understanding and communicating the who, what, where, when, why, and how of the clinics and services for which the computerized patient record (CPR) will be built is an integral part of the implementation process. Formal methodologies have been developed to diagram information flow -- flow charts, state-transition diagram (STDs), data flow diagrams (DFDs). For documentation of the processes at our ambulatory CPR pilot site, flowcharting was selected as the preferred method based upon its vers...

  10. 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.

  11. Phase Diagrams

    Science.gov (United States)

    Dexter Perkins

    This handout and problem set is a stand alone tutorial that introduces students to the basics of phase diagrams and the phase rule. It is a rather lengthy exercise, suitable as a homework assignment. It can replace lectures and yields superior learning.

  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. 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.

  14. 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.

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

    Directory of Open Access Journals (Sweden)

    PALPANDIAN P

    2013-03-01

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

  16. On-line sample processing methods in flow analysis

    OpenAIRE

    Miró, Manuel; Hansen, Elo Harald

    2007-01-01

    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...

  17. Analysis of the Flow Pipe Arrangement in RTM Process

    OpenAIRE

    Jinliang Liu; Xiaoqing Wu

    2009-01-01

    In RTM process, the condition which the flow of resin in the pipeline according with the Darcy's law is the movement of laminar fluid and the Reynolds number less than 1. This paper simulated the flow of the resin in the pipeline by changing the length and diameter of the passageway of pipeline with finite element analytical method. In the result, the relationship of the fluid speed on the exit in pipeline and Reynolds number, also the scope of flow rate of the resin in the pipes can be gaine...

  18. Subsea flow assurance and process monitoring via gamma radiation

    International Nuclear Information System (INIS)

    Condition monitoring and process control with the use of gamma radiation is considered to be the most reliable detection principle for a wide range of applications throughout the oil and gas industries, from measuring mechanical integrity to dynamic process fluid monitoring. The growing numbers of advanced subsea processing projects and pipeline flow assurance studies currently adds an increasing number of subsea applications to the radiation measurement reference list (author) (ml)

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

    International Nuclear Information System (INIS)

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

  20. 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

  1. Inferring Relevance of Matrix and Preferential Flow Processes Flow Multi-Year Well Concentration Data

    Science.gov (United States)

    Preferential and matrix flow are the two dominate processes influencing chemical transport to groundwater. Unfortunately the relevance of these processes is difficult to quantify without chemical flux data. Seventy-one observations times from 31, 3-m wells were evaluated to determine relevance of p...

  2. 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

  3. Contingency diagrams as teaching tools

    OpenAIRE

    Mattaini, Mark A.

    1995-01-01

    Contingency diagrams are particularly effective teaching tools, because they provide a means for students to view the complexities of contingency networks present in natural and laboratory settings while displaying the elementary processes that constitute those networks. This paper sketches recent developments in this visualization technology and illustrates approaches for using contingency diagrams in teaching.

  4. Process intensification using a meso-scale oscillatory flow reactor

    OpenAIRE

    Reis, N.; Vicente, A. A.; J. A. Teixeira

    2009-01-01

    Meso-technologies are currently triggering a paradigm change in the design of chemical and biochemical processes. Mass and heat transfer rates can readily be maximised in smaller, sustainable, cheaper and safer plants, whilst virtually reducing the design of (bio) process unit operations to the intrinsic kinetics of the system. A novel meso-scale reactor running with oscillatory flow mixing was recently developed in the University of Minho in collaboration with the University o...

  5. 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

  6. 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

  7. Flow measurement and control in the defense waste process

    International Nuclear Information System (INIS)

    The Defense Waste Processing Facility (DWPF) for immobilizing Savannah River Plant (SRP) high-level radioactive waste is now under construction. Previously stored waste is retrieved and processed into a glass matrix for permanent storage. The equipment operates in an entirely remote environment for both processing and maintenance due to the highly radioactive nature of the waste. A fine powdered glass frit is mixed with the waste prior to its introduction as a slurry into an electric glass furnace. The slurry is Bingham plastic in nature and of high viscosity. This combination of factors has created significant problems in flow measurement and control. Specialized pieces of equipment have been demonstrated that will function properly in a highly abrasive environment while receiving no maintenance during their lifetime. Included are flow meters, flow control technology, flow switching, and remote connections. No plastics or elastomers are allowed in contact with fluids and all electronic components are mounted remotely. Both two- and three-way valves are used. Maintenance is by crane replacement of process sections, utilizing specialized connectors. All portions of the above are now operating full scale (radioactively cold) at the test facility at SRP. 4 references, 8 figures

  8. 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.

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

    OpenAIRE

    Schleyer, Marc

    2007-01-01

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

  10. 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.

  11. Small scale flow processes in aqueous heterogeneous porous media

    Energy Technology Data Exchange (ETDEWEB)

    Rashidi, M.; Dickenson, E. [Lawrence Livermore National Lab., CA (United States). Environmental Programs Directorate

    1996-04-01

    Small scale flow processes in aqueous heterogeneous porous systems have been studied experimentally via novel nonintrusive fluorescence imaging techniques. The techniques involve 3D visualization and quantification of flow fields within a refractive index-matched transparent porous column. The refractive index-matching yields a transparent porous medium, free from any scattering and refraction at the solid-liquid interfaces, as a result allowing direct optical probing at any point within the porous system. By illuminating the porous regions within the column with a planar sheet of laser beam, flow processes through the porous medium can be observed microscopically, and qualitative and quantitative in-pore transport information can be obtained at a good resolution and a good accuracy. A CCD camera is used to record the fluorescent images at every vertical plane location while sweeping back and forth across the column. These digitized flow images are then analyzed and accumulated over a 3D volume within the column. Series of flow experiments in aqueous, refractive index-matched, porous systems packed with natural mineral particles have been performed successfully in these laboratories.

  12. 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.

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

    Science.gov (United States)

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

    2015-02-01

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

  14. Steady flow approximations to the helium r-process

    Science.gov (United States)

    Cameron, A. G. W.; Cowan, J. J.; Klapdor, H. V.; Metzinger, J.; Oda, T.; Truran, J. W.

    1983-01-01

    A steady flow approximation to the r-process is presented and used for numerical experiments with physical quantities to determine the sensitivity of the process to variations in those quantities. The effect of neutron capture cross sections along the capture path and of recently available improved beta decay rates on the r-process are discussed. The peaks in the observed r-process yield curve near mass numbers 80 and 130 are roughly characterized by a neutron number density of 10 to the 20th per cu/cm; the mean beta decay rates are about 10/s, and the freezing time is comparable to or less than 0.1 s. The peak near mass number 195 is roughly characterized by a neutron number density of 10 to the 21st/cm, the mean beta decay rates are about 100/s, and the freezing time is comparable to or less than 0.01 s. The flow path of the steady state r-process is sensitively dependent upon the neutron capture cross sections in the flow network and on the values of the beta decay rates.

  15. 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.

  16. 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

  17. 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.

  18. Fundamental Processes of Atomization in Fluid-Fluid Flows

    Science.gov (United States)

    McCready, M. J.; Chang, H.-C.; Leighton, D. T.

    2001-01-01

    This report outlines the major results of the grant "Fundamental Processes of Atomization in Fluid-Fluid Flows." These include: 1) the demonstration that atomization in liquid/liquid shear flow is driven by a viscous shear instability that triggers the formation of a long thin sheet; 2) discovery of a new mode of interfacial instability for oscillatory two-layer systems whereby a mode that originates within the less viscous liquid phase causes interfacial deformation as the oscillation proceeds; 3) the demonstration that rivulet formation from gravity front occurs because the local front shape specified by gravity and surface tension changes from a nose to a wedge geometry, thus triggering a large increase in viscous resistance; and 4) extension of the studies on nonlinear wave evolution on falling films and in stratified flow, particularly the evolution towards large-amplitude solitary waves that tend to generate drops.

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

    International Nuclear Information System (INIS)

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

  20. Evaluation of the MODFLOW-2005 Conduit Flow Process.

    Science.gov (United States)

    Hill, Melissa E; Stewart, Mark T; Martin, Angel

    2010-01-01

    The recent development of the Conduit Flow Process (CFP) by the U.S. Geological Survey (USGS) provides hydrogeologic modelers with a new tool that incorporates the non-Darcian, multiporosity components of flow characteristic of karst aquifers. CFP introduces new parameters extending beyond those of traditional Darcian groundwater flow codes. We characterize a karst aquifer to collect data useful for evaluating this new tool at a test site in west-central Florida, where the spatial distribution and cross-sectional area of the conduit network are available. Specifically, we characterize: (1) the potential for Darcian/non-Darcian flow using estimates of specific discharge vs. observed hydraulic gradients, and (2) the temporal variation for the direction and magnitude of fluid exchange between the matrix and conduit network during extreme hydrologic events. We evaluate the performance of CFP Mode 1 using a site-scale dual-porosity model and compare its performance with a comparable laminar equivalent continuum model (ECM) using MODFLOW-2005. Based on our preliminary analyses, hydraulic conductivity coupled with conduit wall conductance improved the match between observed and simulated discharges by 12% to 40% over turbulent flow alone (less than 1%). PMID:20113361

  1. 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.

  2. IGDS/TRAP Interface Program (ITIP). Detailed Design Specification (DDS). [network flow diagrams for coal gasification studies

    Science.gov (United States)

    Jefferys, S.; Johnson, W.; Lewis, R.; Rich, R.

    1981-01-01

    The software modules which comprise the IGDS/TRAP Interface Program are described. A hierarchical input processing output (HIPO) chart for each user command is given. The description consists of: (1) function of the user command; (2) calling sequence; (3) moduls which call this use command; (4) modules called by this user command; (5) IGDS commands used by this user command; and (6) local usage of global registers. Each HIPO contains the principal functions performed within the module. Also included with each function are a list of the inputs which may be required to perform the function and a list of the outputs which may be created as a result of performing the function.

  3. Arrows in Comprehending and Producing Mechanical Diagrams

    Science.gov (United States)

    Heiser, Julie; Tversky, Barbara

    2006-01-01

    Mechanical systems have structural organizations--parts, and their relations--and functional organizations--temporal, dynamic, and causal processes--which can be explained using text or diagrams. Two experiments illustrate the role of arrows in diagrams of mechanical systems. In Experiment 1, people described diagrams with or without arrows,…

  4. Transition rate diagrams — A new approach to the study of selective excitation processes: The spectrum of manganese in a Grimm-type glow discharge

    International Nuclear Information System (INIS)

    The emission spectra of manganese observed using a Grimm-type glow discharge in pure argon, argon with 0.3% v/v hydrogen and pure neon were studied in order to identify major excitation and ionization processes of manganese in the plasma. A new procedure is proposed, in which each observed emission line is associated with the corresponding transition between different states of the Mn atom or Mn ion, and, by considering all the observed transitions from and into a specific state, a measure of the total rate is determined at which this state is radiatively populated and depopulated. These resulting population/depopulation rates are then plotted as function of level energy. Such plots, called here “transition rate diagrams”, show the role of individual states in the formation of the observed spectrum and can be used to identify possible selective excitation processes. Also, cascade excitation by radiative decay of higher excited states can be conveniently evaluated in this way. A detailed description of the observed Mn I and Mn II spectra is given for Ar, Ar–H2 and Ne plasmas and relevant excitation/ionization mechanisms are discussed. Matrix effects in analysis of manganese by glow discharge spectroscopy are discussed. A list of important Mn I and Mn II lines excited in the glow discharge plasma is given. - Highlights: • We measured GD-OES spectra of Mn in Ar, Ar(H) and Ne discharges. • We determined transition rate diagrams of Mn I and Mn II in these discharges. • Using those diagrams, we identified major excitation processes involved

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

    Directory of Open Access Journals (Sweden)

    E. García-Ladona

    2010-05-01

    Full Text Available 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 Niño Southern Oscillation.

  6. An Evaluation Of Digital Processing Capabilities For Improving Detection Of Low Contrast Round Objects In A Radiography By Contrast Detail Diagrams

    Science.gov (United States)

    Bencomo, J. A.; Marsh, L. M...; Morgan, T. J.

    1984-12-01

    In this evaluation contrast-detail diagrams were used to measure the effects on observer performance of several image processing algorithms such as edge enhancement, smoothing and histogram equalization. The observer task was the detection of disk images in a uniform background. A new digital system, DigiRad System One, was used to digitize and postprocess images of a "Rose-Burger" contrast phantom. Results show that detectability of low contrast objects may increase for images taken with standard film/screen combinations. Anticipated changes on the System One may enhance its capabilities significantly.

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

    International Nuclear Information System (INIS)

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

  8. FORTES: Forensic Information Flow Analysis of Business Processes

    OpenAIRE

    Accorsi, Rafael; Mu?ller, Gu?nter

    2010-01-01

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

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

    OpenAIRE

    van Bussel, Emma F; 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 ...

  10. 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).

  11. Anomalous quark diagrams in the virtual V ? P+P', P ? V+P' decays and in the related processes

    International Nuclear Information System (INIS)

    Form factors of the virtual decays V?P+P' and P?V+P' are calculated assuming that the anomaly due to the corresponding quark diagram dominates in the VPP' vertex, where V and P are a vector meson and a pseudoscalar meson. An effect of the obtained form factors upon the electromagnetic and weak P- meson form factors is considered. It is shown that the results coincide with predictions of the standard vector-meson dominance model, if the interactions of the photon and of the W-boson with the pseudoscalar meson are determined by the quark-diagram anomaly in the vertices ?PP and WPP. The effect of the rho??? decay form factors for a virtual rho-meson on the superconvergency of the dispersion relations for the rho??rho? scattering amplitude, as well as on the rho-meson contribution to the ??-scattering lengths, is discussed. Rules for calculation of quark graphs with an arbitrary number of mesons are formulated for the examples of the decays ???+?-?0 and eta(eta')??+?-?

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

    International Nuclear Information System (INIS)

    Neutron radiography is a non-destructive testing technique which makes use of the difference in attenuation characteristics of neutrons in materials. The present note addresses the first step of a study for the application of neutron radiography to the analysis of two-phase flow in a metal duct. Simulation is made using an optical method with water and air in a transparent duct. This gives several useful basic parameters of two-phase flows. Interfacial area concentration and void fraction, for example, can be determined by using an image processing system. Study results show that the higher the superficial gas velocity, the larger the mean void fraction and interfacial area concentration, when the liquid velocity is constant. When the liquid velocity is increased, the mean void fraction decreases. The same tendency is seen for the interfacial area concentration. As the superficial gas velocity increases, the difference between the interfacial area concentrations whose liquid velocities are 0 m-sec and 0.328 m-sec decreases. To determine the accuracy of this image processing system, several images of square holes of a known area in black paper are observed and compared with the real areas. From this observation, the error of the present method is estimated at within 7 %. These study results indicate that the image processing technique is very useful in studying two-phase flows. (Nogami, K.)

  13. Investigation of flow and microstructure in rheometric and processing flow conditions for liquid crystalline pitch

    Science.gov (United States)

    Kundu, Santanu

    The microstructure development within mesophase pitch-based carbon materials depends on the flow history that the pitch is subjected to. Therefore, a fundamental understanding of flow and its influence on the microstructure is required to obtain carbon materials with desired properties. The objective of this research was to investigate the flow and microstructural behavior of a synthetic mesophase pitch (AR-HP) in rheometric and processing flow conditions. In addition, simulation studies were performed to establish a frame work for modeling the flow behavior of this complex material in different flow situations. The steady-shear viscosities obtained from a cone-plate rheometer during increasing rate-sweep experiments exhibited shear-thinning (Region I) and plateau (Region II) responses. However, the slope of the shear-thinning region was only about -0.2, much lower than -0.5 observed in some pitches and liquid-crystalline polymers. This difference could arise from the different molecular constituents of pitches. At higher shear rates, as measured from capillary rheometers, the viscosity values remained almost constant. The transient shear stress responses, as measured from cone-plate rheometer, exhibited nonmonotonic behavior as a function of applied strain at all shear rates and temperatures tested. After rheological experiments, the samples were collected by developing a new experimental protocol for preservation of the sample for microstructural analysis. Microstructural observations obtained from three orthogonal sections, reported for the first time in the literature, indicate that the local maximum in shear stress was due to yielding of initial microstructure. The microstructure became flow oriented with further shearing, and the structure size decreased with increasing shear rates. In addition to high-strain experiments, dynamic experiments were also performed in the linear viscoelastic region where no significant deformation of fluid takes place. The elastic response was found to be strongly dependent on the microstructure, and a lower slope of 0.8 for the elastic modulus in the low-frequency terminal region was observed as compared to 2 observed for flexible chain polymers. Relaxation of microstructure resulted in an increase of storage moduli. However, the relaxation time did not follow the scaling argument, tau ˜ etaa2/ K. It is postulated that the relaxation process is influenced not only by the textural size, but also by layer-plane orientation. The flow-microstructural study was extended to the processing flow conditions and in this case AR-HP mesophase pitch was extruded through custom-made dies using a single-screw extruder. Due to changing dimensions of these dies, the mesophase pitch was subjected to varying shear rates. Microstructural observations suggest that in the capillary region of these dies, the orientation of the layer-plane was approximately radial near the wall. Away from the wall, the deviation of orientation of the layer-planes from the radial direction was significant and some layer-planes were oriented tangentially. In the core, the microstructure was coarse and no preferred orientation of mesophase layerplanes was observed. Simulation studies were performed using constitutive equations for discotic liquid-crystalline materials in simple shear flow, corresponding with the experimental studies. The simulation studies were performed for two different initial conditions that resemble the experimental results. At steady state, the bulk of the discs were found to be oriented at a flow-aligned angle of -64.1°, which is consistent with the theoretical predictions. Although, the simulation studies could not capture the complex microstructure observed experimentally, similarities in flow-aligned domains were observed. This study establishes a frame work to simulate the flow dynamics of complex mesophase pitch in multiscale-mulidimensional problems using the computational facility and expertise of the Center for Advanced Engineering Fibers and Films (CAEFF).

  14. Breviz: Visualizing Spreadsheets using Dataflow Diagrams

    CERN Document Server

    Hermans, Felienne; van Deursen, Arie

    2011-01-01

    Spreadsheets are used extensively in industry, often for business critical purposes. In previous work we have analyzed the information needs of spreadsheet professionals and addressed their need for support with the transition of a spreadsheet to a colleague with the generation of data flow diagrams. In this paper we describe the application of these data flow diagrams for the purpose of understanding a spreadsheet with three example cases. We furthermore suggest an additional application of the data flow diagrams: the assessment of the quality of the spreadsheet's design.

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

    DEFF Research Database (Denmark)

    Jabbari, Masoud; Hattel, Jesper Henri

    2011-01-01

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

  16. Coded ultrasound for blood flow estimation using subband processing

    Science.gov (United States)

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

    2007-03-01

    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 averaging the results yields better performance compared to what would be possible when transmitting a narrow-band pulse directly. Also, the spatial resolution of the narrow-band pulse would be too poor for brightness-mode (B-mode) imaging and additional transmissions would be required to update the B-mode image. In the described approach, there is no need for additional transmissions, because the excitation signal is broadband and has good spatial resolution after pulse compression. Two different coding schemes are used in this paper, Barker codes and Golay codes. The performance of the codes for velocity estimation is compared to a conventional approach transmitting a narrow-band pulse. The study was carried out using an experimental ultrasound scanner and a commercial linear array 7 MHz transducer. A circulating flow rig was scanned with a beam-to-flow angle of 60°. The flow in the rig was laminar and had a parabolic flow-profile with a peak velocity of 0.09 m/s. The mean relative standard deviation of the reference method using an eight cycle excitation pulse at 7 MHz was 0.544% compared to the peak velocity in the rig. Two Barker codes were tested with a length of 5 and 13 bits, respectively. The corresponding mean relative standard deviations were 0.367% and 0.310%, respectively. For the Golay coded experiment, two 8 bit codes were used, and the mean relative standard deviation was 0.335%.

  17. Coded ultrasound for blood flow estimation using subband processing

    DEFF Research Database (Denmark)

    Gran, Fredrik; Udesen, Jesper

    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 averaging the results yields better performance compared to what would be possible when transmitting a narrow-band pulse directly. Also, the spatial resolution of the narrow-band pulse would be too poor for brightness-mode (B-mode) imaging and additional transmissions would be required to update the B-mode image. In the described approach, there is no need for additional transmissions, because the excitation signal is broadband and has good spatial resolution after pulse compression. Two different codin-schemes are used inthis paper, Barker codes and Golay codes. The performance of the codes for velocity estimation is compared to a conventional approach transmitting a narrow-band pulse. The study was carried out using an experimental ultrasound scanner and a commercial linear array 7 MHz transducer. A circulating flow rig was scanned with a beam-to-flow angle of 60 degrees. The flow in the rig was laminar and had a parabolic flow-profile with a peak velocity of 0.09 m/s. The mean relative standard deviation of the reference method using an eight cycle excitation pulse at 7 MHz was 0.544% compared to the peak velocity in the rig. Two Barker codes were tested with a length of 5 and 13 bits, respectively. The corresponding mean relative standard deviations were 0.367% and 0.310%, respectively. For the Golay coded experiment, two 8 bit codes were used, and the mean relative standard deviation was 0.335%.

  18. 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.

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

    Science.gov (United States)

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

    2013-04-22

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

  20. 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...

  1. Microfluidic-SANS: flow processing of complex fluids

    Science.gov (United States)

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

    2015-01-01

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

  2. Microfluidic-SANS: flow processing of complex fluids

    Science.gov (United States)

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

    2015-01-01

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

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

    International Nuclear Information System (INIS)

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

  4. 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.

  5. 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.

  6. Coded Ultrasound for Blood Flow Estimation Using Subband Processing

    DEFF Research Database (Denmark)

    Gran, Fredrik; Udesen, Jesper

    2008-01-01

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

  7. 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

  8. 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.

  9. 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

  10. 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.

  11. 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.

  12. 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.

  13. 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)

  14. 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).

  15. 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

  16. 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).

  17. 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 63.114 (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)

  18. 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)

  19. 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).

  20. 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.

  1. Measuring information flow in networks of stochastic processes

    CERN Document Server

    Amblard, Pierre-Olivier

    2009-01-01

    Social networks are considered in this paper as networks of interacting stochastic processes. We study the problem of inferring the circulation of information between network nodes. To take into account feedback between signals, as well as instantaneous interaction, we show that the adequate measures of information flow are the directed information and the causal conditional directed information. We relate the framework based on directed information theory to the theory of Granger causality in multivariate time series. An important result of the paper is the proof that linear implementation of Granger causality and directed information theory are equivalent in the Gaussian case. This is proved for the bivariate analysis as well as for the multivariate analysis, for which we extend some of Geweke's results. The relations between directed information and transfer entropy are provided. A simulation illustrates the main results obtained in the paper through the problem of inferring effective connectivity in a net...

  2. Diagrams and parameters of process heat supply from commercial-heating plants on the base of HTGR reactors

    International Nuclear Information System (INIS)

    Comparative analysis of several versions of basic layouts of process heat supply from dual-cycle steam-turbine plants with HTGR reactors is considered. The versions differ in organization of heating steam extraction in steam conversion plants (SCP) and by the ways of using drainage of heating steam. Temperature gradient in evaporator is taken as an optimized parameter. It is shown that design solutions affect slightly the optimized parameter. The decisive effect of the steam transportation distance and the degree of process steam overheating in SCP on efficiency of considered layouts was revealed

  3. 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.

  4. Safety- barrier diagrams

    DEFF Research Database (Denmark)

    Duijm, Nijs Jan

    2008-01-01

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

  5. 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...

  6. Transition rate diagrams - A new approach to the study of selective excitation processes: The spectrum of manganese in a Grimm-type glow discharge

    Science.gov (United States)

    Weiss, Zden?k; Steers, Edward B. M.; Pickering, Juliet C.; Mushtaq, Sohail

    2014-02-01

    The emission spectra of manganese observed using a Grimm-type glow discharge in pure argon, argon with 0.3% v/v hydrogen and pure neon were studied in order to identify major excitation and ionization processes of manganese in the plasma. A new procedure is proposed, in which each observed emission line is associated with the corresponding transition between different states of the Mn atom or Mn ion, and, by considering all the observed transitions from and into a specific state, a measure of the total rate is determined at which this state is radiatively populated and depopulated. These resulting population/depopulation rates are then plotted as function of level energy. Such plots, called here “transition rate diagrams”, show the role of individual states in the formation of the observed spectrum and can be used to identify possible selective excitation processes. Also, cascade excitation by radiative decay of higher excited states can be conveniently evaluated in this way. A detailed description of the observed Mn I and Mn II spectra is given for Ar, Ar-H2 and Ne plasmas and relevant excitation/ionization mechanisms are discussed. Matrix effects in analysis of manganese by glow discharge spectroscopy are discussed. A list of important Mn I and Mn II lines excited in the glow discharge plasma is given.

  7. Trajectories in phase diagrams, growth processes and computational complexity how search algorithms solve the 3-Satisfiability problem

    CERN Document Server

    Cocco, S; Cocco, Simona; Monasson, Remi

    2001-01-01

    Most decision and optimization problems encountered in practice fall into one of two categories with respect to any particular solving method or algorithm: either the problem is solved quickly (easy) or else demands an impractically long computational effort (hard). Recent investigations on model classes of problems have shown that some global parameters, such as the ratio between the constraints to be satisfied and the adjustable variables, are good predictors of problem hardness and, moreover, have an effect analogous to thermodynamical parameters, e.g. temperature, in predicting phases in condensed matter physics [Monasson et al., Nature 400 (1999) 133-137]. Here we show that changes in the values of such parameters can be tracked during a run of the algorithm defining a trajectory through the parameter space. Focusing on 3-Satisfiability, a recognized representative of hard problems, we analyze trajectories generated by search algorithms using growth processes statistical physics. These trajectories can c...

  8. Tree Diagrams and Probability

    Science.gov (United States)

    2010-01-01

    This lesson is designed to develop students' ability to create tree diagrams and figure probabilities of events based on those diagrams. This lesson provides links to discussions and activities related to tree diagrams as well as suggested ways to work them into the lesson. Finally, the lesson provides links to follow-up lessons designed for use in succession with the current one.

  9. AFM Diagram Quiz

    Science.gov (United States)

    Dexter Perkins

    This exercise should be used after you think students know what AFM diagrams are and how they work. This is sort of a quiz - to see if they can properly interpret the diagrams. There is no point moving on to real projects that involve AFM diagrams if the students don't understand the basics.

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

    Energy Technology Data Exchange (ETDEWEB)

    P. Persoff

    2004-11-06

    The evaluation of impacts of potential volcanic eruptions on populations and facilities far in the future may involve detailed volcanological studies that differ from traditional hazards analyses. The proximity of Quaternary volcanoes to a proposed repository for disposal of the USA's high-level radioactive waste at Yucca Mountain, Nevada, has required in-depth study of probability and consequences of basaltic igneous activity. Because of the underground nature of the repository, evaluation of the potential effects of dike intrusion and interaction with the waste packages stored in underground tunnels (dnfts) as well as effects of eruption and ash dispersal have been important. These studies include analyses of dike propagation, dike-drift intersection, flow of magma into dnfts, heat and volcanic gas migration, atmospheric dispersal of tephra, and redistribution of waste-contaminated tephra by surficial processes. Unlike traditional volcanic hazards studies that focus on impacts on housing, transportation, communications, etc. (to name a small subset), the igneous consequences studies at Yucca Mountain have focused on evaluation of igneous impacts on nuclear waste packages and implications for enhanced radioactive dose on a hypothetical future ({le} 10000 yrs) local population. Potential exposure pathways include groundwater (affected by in-situ degradation of waste packages by igneous heat and corrosion) and inhalation, ingestion, and external exposure due to deposition and redistribution of waste-contaminated tephra.

  11. Transport phenomena of reactive fluid flow in heterogeneous combustion processes.

    Science.gov (United States)

    Hung, W. S. Y.; Chen, C. S.; Haviland, J. K.

    1972-01-01

    A previously developed computer program was used to model two transient hybrid combustion processes involving tubes of solid Plexiglas. In the first study, representing combustion of a hybrid rocket, the oxidizing gas was oxygen, and calculations were continued sufficiently long to obtain steady-state values. Systematic variations were made in reaction rate constant, mass flow rate, and pressure, alternatively using constant and temperature dependent regression rate models for the fuel surface. Consistent results were obtained, as is evidenced by the values for the mass function of the reaction product and the flame temperature, for which plots are supplied. In the second study, fire initiation in a duct was studied, with an air mixture as the oxidizing gas. It was demonstrated that a satisfactory flame spread mechanism could be reproduced on the computer. In both of the above applications, the general, transient, two-dimensional conservation equations were represented, together with chemical reactions, solid-fuel interface conditions, and heat conduction in the solid fuel.

  12. Between Analogue and Digital Diagrams

    OpenAIRE

    Zoltan Bun

    2012-01-01

    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 diagram)in 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 andfor...

  13. Laser Doppler anemometer signal processing for blood flow velocity measurements

    Science.gov (United States)

    Borozdova, M. A.; Fedosov, I. V.; Tuchin, V. V.

    2015-03-01

    A new method for analysing the signal in a laser Doppler anemometer based on the differential scheme is proposed, which provides the flow velocity measurement in strongly scattering liquids, particularly, blood. A laser Doppler anemometer intended for measuring the absolute blood flow velocity in animal and human near-surface arterioles and venules is developed. The laser Doppler anemometer signal structure is experimentally studied for measuring the flow velocity in optically inhomogeneous media, such as blood and suspensions of scattering particles. The results of measuring the whole and diluted blood flow velocity in channels with a rectangular cross section are presented.

  14. Energy transfer process of anisothermal wall-bounded flows

    Science.gov (United States)

    Aulery, Frédéric; Toutant, Adrien; Bataille, Françoise; Zhou, Ye

    2015-07-01

    Strong temperature gradients introduce a major external agency into the wall-bounded turbulent flows. In these flows, the temperature field and the turbulent velocity field are highly correlated. In fact, standard RANS turbulent models are not able to accurately reproduce these flows. In order to improve the performance of the models, we need to understand how the energy is produced, transferred, and dissipated in a strong anisothermal wall-bounded flow. This letter presents a first detailed investigation on the roles played by each contributor in the energy transfer equation.

  15. Generic phase diagram of active polar films

    OpenAIRE

    Voituriez, R.; Joanny, J. F.; Prost, J.

    2008-01-01

    We study theoretically the phase diagram of compressible active polar gels such as the actin network of eukaryotic cells. Using generalized hydrodynamics equations, we perform a linear stability analysis of the uniform states in the case of an infinite bidimensional active gel to obtain the dynamic phase diagram of active polar films. We predict in particular modulated flowing phases, and a macroscopic phase separation at high activity. This qualitatively accounts for experi...

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

    OpenAIRE

    Arattano, M.; Franzi, L.

    2010-01-01

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

  17. 23 CFR Appendix D to Subpart D of... - Equal Opportunity Compliance Review Process Flow Chart

    Science.gov (United States)

    2010-04-01

    ...2010-04-01 2010-04-01 false Equal Opportunity Compliance Review Process Flow...PROGRAMS Construction Contract Equal Opportunity Compliance Procedures Pt...to Subpart D of Part 230—Equal Opportunity Compliance Review Process...

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

    Science.gov (United States)

    Handayani, Gunawan

    2015-04-01

    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.

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

    Science.gov (United States)

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

  20. Possibilities for relaxing process tube flow trip requirements for Hanford reactors

    Energy Technology Data Exchange (ETDEWEB)

    Waters, E.D.; Hesson, G.M.; Batch, J.M.

    1961-10-17

    The purpose of this report is to describe a means of relaxing the process tube flow trip requirements as now specified for the Hanford reactors. The results of such a relaxation would be a liberalization of flow trip settings on the Panellit pressure gages and higher outlet water temperature limits for sane process tubes.

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

    CERN Document Server

    Labbé, Cyril

    2012-01-01

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

  2. Simulation of fluid flow system in process industries

    OpenAIRE

    Khamkham, Nasser E

    2000-01-01

    A comprehensive and integrated suite of computer software has been developed to simulate the steady, one-dimensional, incompressible fluid flow in pipeline networks. The computer program accommodates Newtonian liquids, but does not generally apply to gas flow unless the assumption of constant density is acceptable. The computer program is written in C language, to solve the basic pipe system equations using the linear theory method. This computer program is written to analyse steady state...

  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. Bregman Voronoi diagrams

    OpenAIRE

    Boissonnat, Jean-Daniel; Nielsen, Frank; Nock, Richard

    2010-01-01

    The Voronoi diagram of a finite set of objects is a fundamental geometric structure that subdivides the embedding space into regions, each region consisting of the points that are closer to a given object than to the others. We may define various variants of Voronoi diagrams depending on the class of objects, the distance function and the embedding space. In this paper, we investigate a framework for defining and building Voronoi diagrams for a broad class of distance functions called Bregman...

  5. Building Venn Diagrams

    Science.gov (United States)

    2007-01-01

    In this lesson plan students watch a video clip of Bianca as she uses Venn diagrams to try to satisfy three people's preferences in pizza toppings. Students practice using Venn diagrams to represent the pizza topping preferences. Learners are then introduced to prime numbers, prime factorization, and the use of Venn diagrams to determine least common multiple and greatest common factor. Support materials are included: Handout: Gleamers and Glow Power, Assessment: Levels A and B and answer keys are provided.

  6. Limits of Voronoi Diagrams

    OpenAIRE

    Lindenbergh, Roderik.

    2002-01-01

    In this thesis we study sets of points in the plane and their Voronoi diagrams, in particular when the points coincide. We bring together two ways of studying point sets that have received a lot of attention in recent years: Voronoi diagrams and compactifications of configuration spaces. We study moving and colliding points and this enables us to introduce `limit Voronoi diagrams'. We define several compactifications by considering geometric properties of pairs and triples o...

  7. Similarity between the spiral arms of Galaxy M51 image and the interface curve of Yin-Yang balance in the Ancient Tai-Chi diagram

    Science.gov (United States)

    Lin, Sui

    2009-03-01

    The particle paths of the Lagrangian flow field between two cylinders simulate well the spiral arms of Galaxy M51 image [1] and the interface curve of the Yin-Yang balance in the ancient Tai-Chi diagram [2]. The particle paths of the Lagrangian flow field involve four parameters. The normalization of the system of equations significantly simplifies the formulation of the flow process and reduces the original four parameters to only one parameter. Furthermore it provides the similarity between the formulation of the spiral arms of Galaxy M51 and that of the interface curve of the Yin-Yang balance in the ancient Tai-Chi diagram.

  8. 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

  9. Erosion due to high flow velocities: A description of relevant processes:

    OpenAIRE

    Bisschop, F.; Visser, P.J.; Van Rhee, C.; Verhagen, H.J.

    2010-01-01

    Convential models for the erosion of non-cohesive sediments overestimate the erosion rate induced by high flow velocities. These high flow velocities occur, for instance, in breaching of embankments or dunes (flow velocities up to 10 m/s) or in jetting sand with a trailing suction hopper dredger (30 to 60 m/s). At these very large flow velocities the erosion process is significantly influenced by the properties of the soil mass (non-cohesive particles). Governing parameters at higher flow vel...

  10. 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.

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

    Directory of Open Access Journals (Sweden)

    Miroslav Grgec

    2007-06-01

    Full Text Available When modeling systems and using UML concepts, a real system can be viewed in several ways. The RUP (Rational Unified Process defines the "4 + 1 view": 1. Logical view (class diagram (CD, object diagram (OD, sequence diagram (SD, collaboration diagram (COD, state chart diagram (SCD, activity diagram (AD, 2.Process view (use case diagram, CD, OD, SD, COD, SCD, AD, 3. Development view (package diagram, component diagram, 4. Physical view (deployment diagram, and 5. Use case view (use case diagram, OD, SD, COD, SCD, AD which combines the four mentioned above. With sequence diagram constructs we are describing object behavior in scope of one use case and their interaction. Each object in system goes through a so called lifecycle (create, supplement object with data, use object, decommission object. The concept of the object lifecycle is used to understand and formalize the behavior of objects from creation to deletion. With help of sequence diagram concepts our paper will describe the way of interaction modeling between objects through lifeline of each of them, and their importance in software development.

  12. Two-Phase Flow Analyses During Throttling Processes.

    Czech Academy of Sciences Publication Activity Database

    Vacek, V.; Vinš, Václav

    2009-01-01

    Ro?. 30, ?. 4 (2009), s. 1179-1196. ISSN 0195-928X Institutional research plan: CEZ:AV0Z20760514 Keywords : capillary tube * dissolved gas * metastable flow Subject RIV: BJ - Thermodynamics Impact factor: 0.702, year: 2009 http://www.springerlink.com/content/052872vq571p5331/

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

    International Nuclear Information System (INIS)

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

  14. 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

  15. Equivariant Homotopy Diagrams

    OpenAIRE

    Ilhan, Asli Guclukan; Unlu, Ozgun

    2013-01-01

    We discuss obstructions to extending equivariant homotopy commutative diagrams to more highly commutative ones and rectifications of these equivariant homotopy commutative diagrams. As an application we show that in some cases these obstructions vanish and the rectifications can be used to construct group actions on products of spheres.

  16. Lenses and Ray Diagrams

    Science.gov (United States)

    Michael Horton

    2009-05-30

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

  17. 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

  18. Algorithmic phase diagrams

    Science.gov (United States)

    Hockney, Roger

    1987-01-01

    Algorithmic phase diagrams are a neat and compact representation of the results of comparing the execution time of several algorithms for the solution of the same problem. As an example, the recent results are shown of Gannon and Van Rosendale on the solution of multiple tridiagonal systems of equations in the form of such diagrams. The act of preparing these diagrams has revealed an unexpectedly complex relationship between the best algorithm and the number and size of the tridiagonal systems, which was not evident from the algebraic formulae in the original paper. Even so, for a particular computer, one diagram suffices to predict the best algorithm for all problems that are likely to be encountered the prediction being read directly from the diagram without complex calculation.

  19. Improved Simulation of Peak Flows Under Climate Change: Post-Processing or Multi-Objective Calibration?

    Science.gov (United States)

    Zhang, X.; Booij, M. J.; Xu, Y. P.

    2014-12-01

    Climate change is expected to have large impacts on peak flows. There are, however, large uncertainties in the simulation of peak flows by hydrological models. This study aims to improve the simulation of peak flows under climate change in Lanjiang catchment, East China by comparing two approaches: post-processing of peak flows and multi-objective calibration. Two hydrological models (SWAT and GR4J) are employed to simulate the daily flows and the peaks-over-threshold method is used to extract peak flows from the simulated daily flows. Three post-processing methods, namely the quantile mapping method and two generalized linear models, are set up to correct the biases in the simulated raw peak flows. Besides, a multi-objective calibration of the GR4J model by taking the peak flows into account in the calibration process is carried out. The regional climate model PRECIS with boundary forcing from two GCMs (HadCM3 and ECHAM5) under greenhouse gas emission scenario A1B is applied to produce the climate data for the baseline period and the future period 2011-2040. The results show that the post-processing methods, particularly quantile mapping method, can correct the biases in the raw peak flows effectively. The multi-objective calibration also resulted in a good simulation performance of peak flows. The final estimated peak flows in the future period show an obvious increase compared with those in the baseline period, indicating there are probably more frequent floods in Lanjiang catchment in the future.

  20. How to Interpret Circuit Diagrams

    Science.gov (United States)

    Lesurf, Jim

    This site presents an explanation of how to interpret circuit diagrams. Two diagrams show the difference between a "short hand" circuit diagram and a more detailed one. The detailed circuit diagram is useful for those first learning circuits in an effort to eventually understand the "short hand" diagram without difficulty.

  1. Special Issue: Design and Engineering of Microreactor and Smart-Scaled Flow Processes

    Directory of Open Access Journals (Sweden)

    Volker Hessel

    2014-12-01

    Full Text Available Reaction-oriented research in flow chemistry and microreactor has been extensively focused upon in special journal issues and books. On a process level, this resembled the “drop-in” (retrofit concept with the microreactor replacing a conventional (batch reactor. Meanwhile, with the introduction of the mobile, compact, modular container technology, the focus is more on the process side, including also providing an end-to-end vision of intensified process design. Exactly this is the focus of the current special issue “Design and Engineering of Microreactor and Smart-Scaled Flow Processes” of the journal “Processes”. This special issue comprises three review papers, five research articles and two communications. [...

  2. Simulations of ductile flow in brittle material processing

    Energy Technology Data Exchange (ETDEWEB)

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

    1988-12-01

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

  3. Relaxation processes for internal waves in mesoscale flow

    OpenAIRE

    Watson, Kenneth M.

    1983-01-01

    A dynamical “test-wave” model has been developed to study transport phenomena within oceanic internal wave fields. This model is extended here to describe effects of a mesoscale flow field on internal wave transport. Previous work with weak-interaction perturbation theory has suggested a substantial enhancement due to mesoscale currents. Extension to the strong-interaction regime in the present paper suggests a relatively small effect due to mesoscale interactions.

  4. Image processing and form recognition applied to the quantitative visualisation of coherent flow structures.

    Science.gov (United States)

    Carbonneau, P. E.; Marquis, G.; Roy, A. G.

    2007-12-01

    Flow visualisation methods such as dye tracers have long been a core methodology for the analysis of turbulent flows. These methods are ideally suited to qualitative observations of coherent structures and their past usage has yielded important insights into turbulent flows. However, the analysis of flow visualisation data need not be limited to qualitative observations. Digital image processing and basic form recognition methods largely developed in the context of remote sensing and earth observation can be applied to flow visualisation experiments in order to extract quantitative information. This paper will demonstrate how such methods can be used on digital films of dye tracer experiments. Specifically, we will examine naturally occurring flow structures observed during a dye tracer experiment conducted in a gravel bed river in Quebec, Canada. The image analysis will be applied in order to automatically identify individual coherent flow structures, measure their size, their orientation in the flow and finally their mean downstream velocity. This novel application of image processing methods to dye tracer experiments allows for quantitative flow visualisations which in turn yield a much more detailed description of coherent flow structures.

  5. A theoretical study of resin flows for thermosetting materials during prepreg processing

    Science.gov (United States)

    Hou, T. H.

    1984-01-01

    A flow model which describes the process of resin consolidation during prepreg lamination was developed. The salient features of model predictions were explored. It is assumed that resin flows in all directions originate from squeezing action between two approaching adjacent fiber/fabric layers. In the horizontal direction, a squeezing flow between two nonporous parallel plates is analyzed, while in the vertical direction a poiseuille type pressure flow through porous media is assumed. Proper force and mass balance was established for the whole system which is composed of these two types of flow. A flow parameter, CF, shows to be a measure of processibility for the curing resin. For a given external load-F the responses of resin flow during prepreg lamination, as measured by CF, are categorized into three regions: (1) the low CF region where resin flows are inhibited by the high chemoviscosity during initial curing stages; (2) the median CF region where resin flows are properly controllable; and (3) the high CF region where resin flows are ceased due to fiber/fabric compression effects. Resin losses in both directions are calculated. Potential uses of this model and quality control of incoming prepreg material are discussed.

  6. 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 developed, that provides detailed knowledge of the FIA profile. It was shown that the flow in a FIA manifold may be characterised by a diffusion coefficient that depends on flow rate, denoted as the kinematic diffusion coefficient. The description was applied to systems involving species of chromium, both in the case of simple diffusion and in the case of chemical reactions. It is suggested that it may be used in the resolution of FIA profiles to obtain information about the content of interference’s, in the study of chemical reaction kinetics and to measure absolute concentrations within the FIA-detector cell.

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

    International Nuclear Information System (INIS)

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

  8. Modeling of Gas Flows in Steelmaking Decarburization Processes

    OpenAIRE

    Song, Zhili Jack

    2013-01-01

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

  9. 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.

  10. The geometry of polynomial diagrams

    OpenAIRE

    Alennikov, Maksim

    2015-01-01

    In this paper we introduce the concept of polynomial diagrams and its area for special polynomials.We study the properties of polynomial area diagrams. The formula for the area of an arbitrary polynomial diagram.

  11. Flow processes near smooth and rough (concave) outer banks in curved open channels

    OpenAIRE

    Blanckaert, Koen; Duarte, A.; Chen, Q.; Schleiss, Anton

    2012-01-01

    Flow processes near the (concave) outer bank in curved river reaches are investigated in a laboratory flume, with focus on the influence of the bank roughness. An outer-bank cell of reversed secondary flow occurs for all the investigated roughness configurations of the outer bank. The cell widens the outer-bank boundary layer, which reduces the flow forcing on the bank, but also advects high-momentum fluid toward the lower part of the bank, which enhances the flow forcing on the bank. Increas...

  12. 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.

  13. 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

  14. Comprehensive design and process flow configuration for micro and nano tech devices

    Science.gov (United States)

    Hahn, Kai; Schmidt, Thilo; Mielke, Matthias; Ortloff, Dirk; Popp, Jens; Brück, Rainer

    2010-04-01

    The development of micro and nano tech devices based on semiconductor manufacturing processes comprises the structural design as well as the definition of the manufacturing process flow. The approach is characterized by application specific fabrication flows, i.e. fabrication processes (built up by a large variety of process steps and materials) depending on the later product. Technology constraints have a great impact on the device design and vice-versa. In this paper we introduce a comprehensive methodology and based on that an environment for customer-oriented product engineering of MEMS products. The development is currently carried out in an international multi-site research project.

  15. Process and apparatus for analyzing gas flows inside hollow bodies

    International Nuclear Information System (INIS)

    This invention concerns a real time technique for analyzing a gas flow moving through a hollow body such as a turbomachine, for obtaining three-dimensional information on the path taken by the gas when it passes through the motor. The difficulties to be overcome are constituted by the rate at which the gases move in the motor, the spreading of the gas flow in the body and the fact that the tracer employed in this analysis contaminates the exhaust gases, and possibly some of the motor, thereby leading to possible pollution hazards. This invention overcomes these troubles by using isotopes specially chosen for their short half life and the high radiation energy they generate, and by ensuring that the irradiation of the tracer substance occurs so as to produce an activity in the isotopes that is as great as possible and at the same time so as to enable the tracer to be injected in the motor as from the irradiation chamber for a very short period. The isotopes can be produced by bombardments of neutrons or by charged particles on to appropriate targets. A cyclotron is preferred as a source of charged particles

  16. Numerical investigation of dimensionless numbers of Si melt flow in directional solidification process for PV cells

    Science.gov (United States)

    Srinivasan, M.; Ramasamy, P.

    2014-04-01

    Numerical simulations of directional solidification of Si melt are performed to study the heat transfer characteristics like stream line flow, Peclet cell number and cell Reynolds number. Dimensionless numbers are of key importance in parametric analysis of non-linear complex transport phenomena of bulk silicon growth process. They are also extremely useful in understanding of the heat and mass transfer of fluid flow on Si melt during crystal growth processes. The flow and thermal pattern influences the quality of the crystal through the convective heat and mass transport. The art of dimensionless numbers like Peclet cell numbers, Reynolds cell numbers on the flow field were studied with the help of numerical simulation. The computations are carried out in a 2D axisymmetric model using the finite-element technique. The results indicate that thermal forces have a dramatic effect on the flow of silicon melt. The simulation results are in reasonable agreement with the predictions of the theoretical approach.

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

    CERN Document Server

    Brenner, Howard

    1992-01-01

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

  18. 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...

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

    Science.gov (United States)

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

    2012-01-01

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

  20. 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...

  1. The Stedman diagram revisited

    International Nuclear Information System (INIS)

    The Stedman diagram has been used for some years to display aspects of the performance of instruments measuring surface roughness. Such diagrams are herein employed to compare the features of a range of proprietary measuring instruments, including contact and non-contact devices. An extension of the basic diagram is proposed, which would allow it to include a further aspect: the speed of data collection. Figures of merit based on the revised diagram are computed, which enable instruments to be ranked on these particular aspects of their performance. Contact instruments emerge as comparable to non-contact, as their slower rate of data acquisition can be offset by the greater area they can access in amplitude–wavelength space. (paper)

  2. EFFICIENT TRANSFORMATION OF USE CASE MAIN SUCCESS SCENARIO STEPS INTO BUSSINESS OBJECT RELATION (BORM) DIAGRAMS FOR EFFECTIVE BUSSINESS PROCESS REQUIREMENT ANALYSIS

    OpenAIRE

    ATHANASIOS PODARAS; JOSEF MORAVEC; MARTIN PAPIK

    2012-01-01

    The basic part of an innovative and modern approach to business processrequirement analysis which is based on the simultaneous utilization of UML Use Caseapproach and the Business Object Relation Modelling approach is analyzed in thepresent paper. Precisely the transition rules by which the Use Case Main SuccessScenario steps are converted into to a BORM diagram, entitled as the Use Case ToBORM Transformation Algorithm (UCBTA) transition rules, are presented as apattern based method which lea...

  3. 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.

  4. Hopf algebras of diagrams

    OpenAIRE

    Duchamp, Gerard Henry Edmond; Luque, Jean-gabriel; Novelli, Jean-christophe; Tollu, Christophe; Toumazet, Frederic

    2007-01-01

    We investigate several Hopf algebras of diagrams related to Quantum Field Theory of Partitions and whose product comes from the Hopf algebras WSym or WQSym respectively built on integer set partitions and set compositions. Bases of these algebras are indexed either by bipartite graphs (labelled or unlabbeled) or by packed matrices (with integer or set coefficients). Realizations on biword are exhibited, and it is shown how these algebras fit into a commutative diagram. Hopf ...

  5. Labelings for Decreasing Diagrams

    OpenAIRE

    Zankl, Harald; Felgenhauer, Bertram; Middeldorp, Aart

    2011-01-01

    This article is concerned with automating the decreasing diagrams technique of van Oostrom for establishing confluence of term rewrite systems. We study abstract criteria that allow to lexicographically combine labelings to show local diagrams decreasing. This approach has two immediate benefits. First, it allows to use labelings for linear rewrite systems also for left-linear ones, provided some mild conditions are satisfied. Second, it admits an incremental method for prov...

  6. Drawing Activity Diagrams

    OpenAIRE

    Siebenhaller, Martin; Kaufmann, Michael

    2006-01-01

    Activity diagrams experience an increasing importance in the design and description of software systems. Unfortunately, previous approaches for automatic layout support fail or are just insufficient to capture the complexity of the related requirements. We propose a new approach tailored to the needs of activity diagrams which combines the advantages of two fundamental layout concepts called "Sugiyama's approach" and "topology-shape-metrics approach", originally develope...

  7. Traffic engineering eye diagram

    OpenAIRE

    Kowalik, Karol; Collier, Martin

    2005-01-01

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

  8. Homotopy theory of diagrams

    OpenAIRE

    Chacholski, Wojciech; Scherer, Jerome

    2001-01-01

    In this paper we develop homotopy theoretical methods for studying diagrams. In particular we explain how to construct homotopy colimits and limits in an arbitrary model category. The key concept we introduce is that of a model approximation. Our key result says that if a category admits a model approximation then so does any diagram category with values in this category. From the homotopy theoretical point of view categories with model approximations have similar properti...

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

    International Nuclear Information System (INIS)

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

  10. Electrical Processes in a Flowing Plasma with Cold Electrodes

    International Nuclear Information System (INIS)

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

  11. An Improved Experimental Method for Simulating Erosion Processes by Concentrated Channel Flow

    OpenAIRE

    Chen, Xiao-yan; Zhao, Yu; Mo, Bin; Mi, Hong-Xing

    2014-01-01

    Rill erosion is an important process that occurs on hill slopes, including sloped farmland. Laboratory simulations have been vital to understanding rill erosion. Previous experiments obtained sediment yields using rills of various lengths to get the sedimentation process, which disrupted the continuity of the rill erosion process and was time-consuming. In this study, an improved experimental method was used to measure the rill erosion processes by concentrated channel flow. By using this met...

  12. Optimizing evacuation flow in a two-channel exclusion process

    International Nuclear Information System (INIS)

    We use a basic set-up of two coupled exclusion processes to model a stylized situation in evacuation dynamics, in which evacuees have to choose between two escape routes. The coupling between the two processes occurs at one common point at which particles are injected; the process can be controlled by directing incoming individuals into either of the two escape routes. On the basis of a mean-field approach we determine the phase behaviour of the model, and analytically compute optimal control strategies, maximizing the total current through the system. Results are confirmed by numerical simulations. We also show that dynamic intervention, exploiting fluctuations about the mean-field stationary state, can lead to a further increase in total current

  13. A Simulation of Friction-Stir Processing for Temperature and Material Flow

    Science.gov (United States)

    Hamilton, Carter; W?glowski, Marek Stanis?aw; Dymek, Stanis?aw

    2015-04-01

    Utilizing a tool without a pin, cast AlSi9Mg aluminum alloy was modified by friction-stir processing. Since the tool design specifically targets the microstructure within the surface layers, the process is more appropriately termed friction-stir surfacing. A coupled numerical model of this special friction-stir process was developed to visualize the material flow patterns and temperature distribution. As the tool transports surface material from the leading edge toward the retreating side of the tool, the material follows the scroll of the tool shoulder toward the tool center with each tool rotation. At or near the tool center, the material flows into the workpiece thickness, forming the vortex of a process zone. Depending on the processing conditions, i.e., tool velocity and rotation speed, an upward material flow also develops within the process zone. Due to the flow of cooler, unprocessed material into the process zone, the temperature profile on the tool/workpiece interface is skewed toward the advancing side and leading edge with higher processing temperatures occurring in these locations. However, the process parameters influence the shape and magnitude of the temperature distribution on this surface.

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

    OpenAIRE

    Labbé, Cyril

    2012-01-01

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

  15. The Physical Flow of Materials and the Associated Costs in the Production Process of a Rolling Mill

    OpenAIRE

    Holisz-Burzy?ska, J.; Staniewska, E.; Budzik, R.

    2007-01-01

    Efficiency of resources use is, in a large extent, determined by the organization of production flow and the way of their control. The optimization of materials flow in the production process requires the identification of physical flows of goods and it cost. In the article the physical flow process of materials stream in the production process in one of Polish rolling mill and also its logistics analysis and cost analysis are presented.

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

    OpenAIRE

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

  17. Variable heat-flow patterns and hydrothermal processes near the Mid-Atlantic Ridge

    Science.gov (United States)

    Lucazeau, Francis

    2014-05-01

    Oceanic heat-flow is commonly affected by water circulation. The primary mechanism was identified by Lister (1972) near the Juan de Fuca ridge (NE Pacific) and attributed to hydrothermal flow within the oceanic basement: sea-water recharges at certain seamounts, flows within the high-permeability basement below the sediments and discharges at other seamounts. As a result, the heat-flow measured at the ocean bottom is significantly lower than expected for a conductively cooling lithosphere, as long as the fluid is not in equilibrium with the host rock. But this is not the only mechanism for low heat-flow values in the oceanic lithosphere: near the Mid-Atlantic ridge, Langseth et al (1992) have identified the process of sea-water drawdown into the sediments. Here we present results from a recent heat-flow survey (OCEANOGRAFLU, June 2013) on the Mid-Atlantic Ridge flanks at about 35°N, close to the Oceanographer fracture zone, where we have observed similar evidences that sea-water can flow directly into the surficial sediments. Where the heat-flow is lower than the conductive cooling values, the temperature-depth profiles are systematically non-linear, showing sigmoid shapes or negative gradients, and the sediment porewaters have compositions close to that of sea-water. No clear evidence for basement recharge or discharge is observed, which differs significantly from the results of a previous study 400 km North, where the heat-flow pattern was more consistent with water flowing into the oceanic basement rather than into the sediment (Lucazeau et al, 2006). We will present the relevant observations and examine the possible causes for the different processes affecting the heat-flow in the Mid-Atlantic Ridge flanks.

  18. Power supply - Interpretation of phase vector diagrams

    International Nuclear Information System (INIS)

    This article discusses the problems involved in providing real-time measurement and billing of active and reactive power for the various players in the liberalised electricity market. Large amounts of data have to be made available to various instances and meet stringent standards at the same time. The article discusses one of the factors involved, i.e. the interpretation of concatenated vector diagrams that represent active and reactive power flow. The basics of how active and reactive power are represented are presented and the conventions agreed on by the various players in the market are noted. Four-quadrant diagrams are described on the basis of an example taken from practice.

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

    Science.gov (United States)

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

    2015-02-01

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

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

    OpenAIRE

    Marais, Su-anrie

    2012-01-01

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

  1. 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.

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

    International Nuclear Information System (INIS)

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

  3. 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)

  4. 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.

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

    International Nuclear Information System (INIS)

    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

  6. 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.

  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. 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.

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

    International Nuclear Information System (INIS)

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

  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. 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.)

  12. 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.

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

    OpenAIRE

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

    2011-01-01

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

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

    International Nuclear Information System (INIS)

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

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

    Directory of Open Access Journals (Sweden)

    Mohammed Khennich

    2014-05-01

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

  16. 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.

  17. Hopf algebras of diagrams

    CERN Document Server

    Duchamp, Gerard Henry Edmond; Novelli, Jean-Christophe; Tollu, Christophe; Toumazet, Frederic

    2007-01-01

    We investigate several Hopf algebras of diagrams related to Quantum Field Theory of Partitions and whose product comes from the Hopf algebras WSym or WQSym respectively built on integer set partitions and set compositions. Bases of these algebras are indexed either by bipartite graphs (labelled or unlabbeled) or by packed matrices (with integer or set coefficients). Realizations on biword are exhibited, and it is shown how these algebras fit into a commutative diagram. Hopf deformations and dendriform structures are also considered for some algebras in the picture.

  18. Diblock copolymer phase diagram

    Science.gov (United States)

    Iacovella, Christopher R.

    2006-11-20

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

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

    Directory of Open Access Journals (Sweden)

    Mohammad I. Muhairat

    2010-01-01

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

  20. Simulation based flow distribution network optimization for vacuum assisted resin transfer moulding process

    Science.gov (United States)

    Hsiao, Kuang-Ting; Devillard, Mathieu; Advani, Suresh G.

    2004-05-01

    In the vacuum assisted resin transfer moulding (VARTM) process, using a flow distribution network such as flow channels and high permeability fabrics can accelerate the resin infiltration of the fibre reinforcement during the manufacture of composite parts. The flow distribution network significantly influences the fill time and fill pattern and is essential for the process design. The current practice has been to cover the top surface of the fibre preform with the distribution media with the hope that the resin will flood the top surface immediately and penetrate through the thickness. However, this approach has some drawbacks. One is when the resin finds its way to the vent before it has penetrated the preform entirely, which results in a defective part or resin wastage. Also, if the composite structure contains ribs or inserts, this approach invariably results in dry spots. Instead of this intuitive approach, we propose a science-based approach to design the layout of the distribution network. Our approach uses flow simulation of the resin into the network and the preform and a genetic algorithm to optimize the flow distribution network. An experimental case study of a co-cured rib structure is conducted to demonstrate the design procedure and validate the optimized flow distribution network design. Good agreement between the flow simulations and the experimental results was observed. It was found that the proposed design algorithm effectively optimized the flow distribution network of the part considered in our case study and hence should prove to be a useful tool to extend the VARTM process to manufacture of complex structures with effective use of the distribution network layup.

  1. A new enabling technology for convenient laboratory scale continuous flow processing at low temperatures.

    Science.gov (United States)

    Browne, Duncan L; Baumann, Marcus; Harji, Bashir H; Baxendale, Ian R; Ley, Steven V

    2011-07-01

    A new machine for conducting continuous flow processes at low temperatures on a laboratory scale is reported. The use of this cryogenic flow reactor has been demonstrated by the preparation of a variety of (hetero)aromatic boronic acids and esters via lithium halogen exchange chemistry. Furthermore, scale-up of the reaction conditions not only demonstrates the application of this device for the preparation of useful building blocks but also combines the ability to process n-butyllithium directly through pump heads attached to the unit. PMID:21615126

  2. Generalized performance diagrams for steam turbine systems

    International Nuclear Information System (INIS)

    Two generalized diagrams have been prepared for the steam turbine performance estimate. The diagrams can predict the turbine net heat rate for various turbine exhaust pressures and loadings. The turbine systems covered in these diagrams have the steam conditions either supercritical or subcritical, and the power output in the range of 400,000 kW to 800,000 kW. The turbine has 4 or 6 exhaust flows and the last stage blade length 23, 26, 30 or 33.5 inches. The basic approach is to normalize the turbine heat rates and express them in terms of turbine heat rates and express them in terms of turbine output per unit area of exhaust flow. The turbine exhaust pressure is treated as a parameter. Approximately 30 steam turbine system have been simulated by computer and the performance data were utilized in the construction of the generalized diagrams. The values predicted by this approach are in good agreement with the actual data

  3. 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.

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

    International Nuclear Information System (INIS)

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

  5. 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.

  6. 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.

  7. Coherent Structures and Mass Exchange Processes in Channel Flow with Spanwise Obstructions

    Science.gov (United States)

    McCoy, Andy; Constantinescu, George; Weber, Larry

    2004-11-01

    Well resolved Large Eddy Simulations are performed to investigate flow phenomena resulting from two spanwise vertical obstructions in a channel. The channel Reynolds number is 13,600, the upstream flow is fully turbulent and the obstructed area represents 17section. In practice this flow is similar to river flow around groyne fields (embayments). Of particular interest is the study of the horseshoe vortex (HV) system at the base of the obstructions that has been shown to control sediment scour and deposition processes that cause structural stability problems. The dynamics of mass exchange between the main channel and the embayment field (between the obstructions) has a major influence on the overall longitudinal dispersion in river flow. The present investigation focuses on the study of the structure and spectral content of the vortices inside the HV system and the study of the mixing processes (exchange of dissolved matter) between the main channel and the embayment. A dynamic Smagorinsky SGS model is used within an unstructured non-dissipative Navier-Stokes solver to account for turbulence effects. The distribution of the bed shear stress was analyzed relative to the capacity of the flow to entrain sediment.

  8. Plagioclase Phase Diagram

    Science.gov (United States)

    Dexter Perkins

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

  9. Technology Logic Diagrams

    International Nuclear Information System (INIS)

    A planning and management tool was developed that relates environmental restoration and waste management problems to technologies that can be used to remediate these problems. Although the Technology Logic Diagram has been widely used within the US Department of Energy's Office of Environmental Restoration and Waste Management, it can be modified for use during the planning of any waste management and environmental cleanup effort

  10. Venn Diagrams and Logic

    Science.gov (United States)

    2011-01-04

    This math lesson from Illuminations uses Venn diagrams to illustrate direct, indirect and transitive reasoning. Students will learn the definitions of direct, indirect and transitive reasoning and give examples of each. Several student activity sheets are included. The material is intended for grades 9-12 and should require 2 and a half class periods to complete.

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

    Directory of Open Access Journals (Sweden)

    Boutros Paul C

    2011-01-01

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

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

    Science.gov (United States)

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

    2011-12-01

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

  13. The Semigroup of Betti Diagrams

    CERN Document Server

    Erman, Daniel

    2008-01-01

    The recent proof of the Boij-Soederberg conjectures reveals new structure about Betti diagrams of modules, giving a complete description of the cone of Betti diagrams. To understand the integral structure of Betti diagrams, we investigate the semigroup of Betti diagrams. We answer several fundamental questions about this semigroup, such as a proof that the semigroup is finitely generated. We also produce numerous examples which belong to the cone of Betti diagrams but which do not equal the Betti diagram of an actual module.

  14. Discrete stochastic models for traffic flow

    OpenAIRE

    Schreckenberg, M.; Schadschneider, A.; Nagel, K.; Ito, N.

    1994-01-01

    We investigate a probabilistic cellular automaton model which has been introduced recently. This model describes single-lane traffic flow on a ring and generalizes the asymmetric exclusion process models. We study the equilibrium properties and calculate the so-called fundamental diagrams (flow vs.\\ density) for parallel dynamics. This is done numerically by computer simulations of the model and by means of an improved mean-field approximation which takes into account short-...

  15. Hydrodynamic viability of chemical looping processes by means of cold flow model investigation

    International Nuclear Information System (INIS)

    Highlights: ? Double loop circulating fluidized bed is proposed for chemical looping processes. ? Overview of the cold flow model (CFM) scaling criteria is provided. ? A full scale CFM was built for hydrodynamics validation and scale-up estimations. ? The CFM was tested resembling design conditions, off-design, reforming, etc. ? The CFM performance is described in terms of solids exchange and pressure. -- Abstract: SINTEF Energy Research and the Norwegian University of Science and Technology – NTNU have proposed a 150 kWth reactor system design aiming at further development of chemical looping processes. It consists of a double loop circulating fluidized bed, meant to be used as a platform to study atmospheric chemical looping combustion configurations, as well as other possible chemical looping processes e.g. gas turbine combustion and reforming. The hydrodynamic viability of the design needs to be tested by means of a cold flow model, operated without chemical reactions. An evaluation of the state of the art within cold flow model testing was done. It led to the choice of building a full scale (i.e. 1:1) cold model of the 150 kWth hot rig design, in order to reduce wall-effects which have considerably larger influence at smaller reactor diameters than on larger ones. The cold flow model was extensively tested and experimental results are presented. The aimed design condition, mirroring a chemical looping combustion process adapted to steam generation, was achieved successfully and in a stable way. The performance of the reactor system was further tested in off-design conditions to define operational guidelines for the hot operation. In addition, attempts were done to resemble other chemical looping processes, getting some understanding of how the reactor system may perform and consequently providing solid hydrodynamic bases to improve the design for those applications. In all cases, stable operational sets were found in order to satisfy the cold flow model hydrodynamic requirements consistently with the actual high temperature processes.

  16. Sequencing Jobs with Uncertain Processing Times and Minimizing the Weighted Total Flow Time

    OpenAIRE

    Sotskov, Yuri; Egorova, Natalja

    2008-01-01

    We consider an uncertain version of the scheduling problem to sequence set of jobs J on a single machine with minimizing the weighted total flow time, provided that processing time of a job can take on any real value from the given closed interval. It is assumed that job processing time is unknown random variable before the actual occurrence of this time, where probability distribution of such a variable between the given lower and upper bounds is unknown before scheduling. W...

  17. 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 ...

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

    Science.gov (United States)

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

  19. 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.

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

    International Nuclear Information System (INIS)

    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.

  1. 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.

  2. 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.…

  3. An Introduction to Tree Diagrams

    Science.gov (United States)

    Stu Cork

    2014-01-01

    This brief article describes the use of tree diagrams in calculating probabilities. The author provides examples of how tree diagrams are used to calculate specific probabilities and why the language chosen relates to the operations used to find the probability.

  4. Confluence by Decreasing Diagrams ? Formalized

    OpenAIRE

    Zankl, Harald

    2013-01-01

    This paper presents a formalization of decreasing diagrams in the theorem prover Isabelle. It discusses mechanical proofs showing that any locally decreasing abstract rewrite system is confluent. The valley and the conversion version of decreasing diagrams are considered.

  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. GIS-based modeling of debris flow processes in an Alpine catchment, Antholz valley, Italy

    Science.gov (United States)

    Sandmeier, Christine; Damm, Bodo; Terhorst, Birgit

    2010-05-01

    Debris flows are frequent natural hazards in mountain regions, which seriously can threat human lives and economic values. In the European Alps the occurrence of debris flows might even increase with respect to climate change, including permafrost degradation, glacier retreat and variable precipitation patterns. Thus, detailed understanding of process parameters and spatial distribution of debris flows is necessary to take appropriate protection measures for risk assessment. In this context, numerical models have been developed and applied successfully for simulation and prediction of debris-flow hazards and related process areas. In our study a GIS-based model is applied in an alpine catchment to address the following questions: Where are potential initiating areas of debris flows? How much material can be mobilized? What is the influence of topography and precipitation? The study area is located in the Antholz valley in the eastern Alps of Northern Italy. The investigated catchment of the Klammbach creek comprises 6.5 km² and is divided into two sub-catchments. Geologically it is dominated by metamorphic rock and altitudes range between 1310 and 3270 m. In summer 2005 a debris flow of more than 100000 m³ took place, originating from a steep, sparsely vegetated debris cone in the western part of the catchment. According to a regional study, the lower permafrost boundary in this area has risen by 250 m. In a first step, during a field survey, geomorphological mapping was performed, several channel cross-sections were measured and sediment samples were taken. Using mapping results and aerial images, a geomorphological map was created. In further steps, results from the field work, the geomorphological map and existing digital data sets, including a digital elevation model with 2.5 m resolution, are used to derive input data for the modeling of debris flow processes. The model framework ‘r.debrisflow' based on GRASS GIS is applied (Mergili, 2008*), as it is capable of simulating the potential spatial patterns of debris flow deposition, as well as their initiation and movement. Furthermore it is a freely available and opensource software and can thus be improved and extended. ‘r.debrisflow' couples a hydraulic, a slope stability, a sediment transport and a debris flow runout model, which are combined differently in 6 simulation modes. In a first step, model parameters are calibrated using the runout only mode with known parameters of the 2005 debris flow. Finally, the full mode will be used to evaluate the debris-flow potential of the whole catchment. First results from the geomorphological mapping reveal numerous surface forms, like levees, debris flow lobes or scars that indicate past and recent debris flow activity in the area. In both sub-catchments, there are large areas of unconsolidated, sparsely or unvegetated sediments, surrounded by high rock walls, which conduct precipitation rapidly into the debris. The two sub-catchments, however, have different topographic characteristics, which can be analyzed with the model in more detail. In a next step, the potential starting areas of future debris flows shall be identified and the potential amount of mobilized material shall be estimated by the model. *Mergili, M. (2008): Integrated modelling of debris flows with Open Source GIS. Ph.D. thesis. University of Innsbruck. http://www.uibk.ac.at/geographie/personal/mergili/dissertation.pdf

  7. Preferential flow processes in unsaturated spoil heaps and heterogeneous mine soils

    Energy Technology Data Exchange (ETDEWEB)

    Gerke, H.H. [Zentrum fuer Agrarlandschafts- und Landnutzungsforschung (ZALF) e.V., Muencheberg (Germany). Institut fuer Bodenlandschaftsforschung

    2001-07-01

    Environmental impact assessment of opencast lignite strip-mining operations is often based on predictions of the hydrological situation. Predictive tools are models which were developed for 'undisturbed' geologic formations or soils. Overburden spoil heaps, however, are mixtures of geological sediments, which are different in texture and mineralogical composition. Physical and chemical properties exhibit small-distance spatial variability and spatial structures which may affect flow and transport. This paper tries to conceptualize flow and transport processes considering spatial compartments and temporal development of heaps and soil properties. The analysis of numerical flow and transport simulations for 2D spoil cross-sections and of dye-tracer and cell-lysimeter experiments in afforested mine soil suggest that flow along preferential pathways occurs in various forms and intensities. Preferential flow processes can be important for determining the water and element balances of afforested spoils to predict the stability of ecosystems, for estimating the development of recultivated mine soils, and for improving calculations of ground water recharge or predictions of acid mine drainage. 10 refs.

  8. 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.

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

    International Nuclear Information System (INIS)

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

  10. Modeling Yin-Yang balance in tai-chi diagram with a melting-freezing rotating device part 3 — The contemporary tai-chi diagram, the yuan-chi diagram and the Fu Xi's eight trigrams

    Science.gov (United States)

    Lin, Sui; Chen, Tzu-Fang

    2002-11-01

    The physical model describing the Yin-Yang balance in the tai-chi diagram via the melting and freezing processes in a rotating device presented in parts 1 and 2 is further developed for the contemporary tai-chi diagram and in the yuan-chi diagram. The contemporary tai-chi diagram shown in Fig.1 is a simplification form of the ancient tai-chi diagram presented in Reference [2]. There are two semi-circles forming the interface curve between the yin and yang in the contemporary tai-chi diagram. By knowing the location of the interface between the yin and yang in the contemporary tai-chi diagram, the requirement for the simulation model is to find the condition to match the interface location. The simplification changes not only the structure but also the physical insight of the ancient tai-chi diagram, which will be described in the present study. The yuan-chi diagram shown in Fig.2 is the combination of the Master Chen’s tai-chi diagram presented in References [1,2] and the contemporary tai-chi diagram. The formulation of the yuan-chi diagram is similar to that of contemporary tai-chi diagram. The Fu Xi’s eight trigrams present three levels of yin-yang relation that are a natural result from the contemporary tai-chi diagram, which will be described in the last part of this study.

  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. Linking diagrams for free

    CERN Document Server

    Hughes, Dominic J D

    2008-01-01

    Linking diagrams with path composition are ubiquitous, for example: Temperley-Lieb and Brauer monoids, Kelly-Laplaza graphs for compact closed categories, and Girard's multiplicative proof nets. We construct the category Link=Span(iRel), where iRel is the category of injective relations (reversed partial functions) and show that the aforementioned linkings, as well as Jones-Martin partition monoids, reside inside Link. Path composition, including collection of loops, is by pullback. Link contains the free compact closed category on a self-dual object (hence also the looped Brauer and Temperly-Lieb monoids), and generalises partition monoids with partiality (vertices in no partition) and empty- and infinite partitions. Thus we obtain conventional linking/partition diagrams and their composition "for free", from iRel.

  13. Legendrian graphs and quasipositive diagrams

    OpenAIRE

    Baader, Sebastian; Ishikawa, Masaharu

    2006-01-01

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

  14. Penguin diagram in supersymmetric theories

    International Nuclear Information System (INIS)

    We have studied the penguin diagram in supersymmetric SU(3)/sub C/ x SU(2) x U(1) theories. It is found that the new penguin diagram introduced by supersymmetry has a structure similar to the usual penguin diagram. Its contribution, though comparable in the case of exact supersymmetry, is shown to be small when supersymmetry is broken

  15. The Semigroup of Betti Diagrams

    OpenAIRE

    Erman, Daniel

    2008-01-01

    The recent proof of the Boij-Soederberg conjectures reveals new structure about Betti diagrams of modules, giving a complete description of the cone of Betti diagrams. We begin to expand on this new structure by investigating the semigroup of Betti diagrams. We prove that this semigroup is finitely generated, and we answer several other fundamental questions about this semigroup.

  16. Trion ladder diagrams

    OpenAIRE

    Combescot, M.; Betbeder-Matibet, O.

    2002-01-01

    We first derive a new ``commutation technique'' for an exciton interacting with electrons, inspired from the one we recently developed for excitons interacting with excitons. These techniques allow to take \\emph{exactly} into account the possible exchanges between carriers. We use it to get the $\\mathrm{X}^-$ trion creation operator in terms of exciton and free-electron creation operators. In a last part we generate the ladder diagrams associated to these trions. Although si...

  17. Unconstrained Influence Diagrams

    OpenAIRE

    Jensen, Finn Verner; Vomlelova, Marta

    2012-01-01

    We extend the language of influence diagrams to cope with decision scenarios where the order of decisions and observations is not determined. As the ordering of decisions is dependent on the evidence, a step-strategy of such a scenario is a sequence of dependent choices of the next action. A strategy is a step-strategy together with selection functions for decision actions. The structure of a step-strategy can be represented as a DAG with nodes labeled with action variables....

  18. Two-Loop Beta Functions without Feynman Diagrams

    International Nuclear Information System (INIS)

    Starting from a consistency requirement between T -duality symmetry and renormalization group flows, the two-loop metric beta function is found for a d=2 bosonic sigma model on a generic, torsionless background. The result is obtained without Feynman diagram calculations, and represents further evidence that duality symmetry severely constrains renormalization flows. copyright 1997 The American Physical Society

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

    International Nuclear Information System (INIS)

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

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

    Directory of Open Access Journals (Sweden)

    Fei Simiao

    2013-01-01

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

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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…

  6. Velocity distribution as a result of the interaction between organizational processes in shear flows

    Directory of Open Access Journals (Sweden)

    Stefan N. SAVULESCU

    2014-12-01

    Full Text Available This paper continues the recent research of the authors concerning the interaction between the micro and macro flow structure domains (further on called IPmMD. The authors propose a probabilistic type approach of the IPmMD, in plane boundary layer, channel and pipe flows. This process, purely theoretical expressed by using transformations associated to transversal coordinate, tends to ensure the equipartition of the kinetic energy and to lead to a minimum in information transmission in the space-time ensemble. Taking into account several velocity distributions as not mutually exclusive events, new distributions are obtained by a probabilistic type union of the events. These new distributions present important aspects related to the classical transition from the laminar-to-turbulent regime. In this way, as an example, the parabolic-laminar and the linear distributions lead to a velocity distribution very close to experimental data corresponding to the rough pipe flow.

  7. Coupled turbulent flow, heat transport in twin-roll casting stainless strip process

    International Nuclear Information System (INIS)

    A fully coupled fluid flow, heat transport model was developed to analyze turbulent flow, solidification in twin-roll casting stainless strip process. Transport equations of the total mass, momentum, energy for the system were solved using a continuum model, wherein the equations are valid for the solid, liquid, and mushy zones in the casting process. A new version of the low-Reynolds number k-· model was adopted to incorporate turbulent effects on transport processes in the system. A control-volume-based finite element method was employed to solve the conservation equations associated with appropriate boundary conditions. Because of the high nonlinearity of the equations, a number of techniques were used to accelerate the convergence processes. The effects of the factors such as roll-casting speed, steel grade, nozzle configuration on the flow pattern, solidification profile, heat flux changing between the sump and the roll and the temperature of the strip face were calculated. Some of the calculated results were compared with available experimental measurements, and they are in reasonable agreements. The effect of the factors such as casting temperature, casting speed on as-cast structures of the stainless strips were also analyzed by some metallographic photos. Some important parameters were obtained. (author)

  8. 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.

  9. 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.)

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

    Directory of Open Access Journals (Sweden)

    Nikolai Nikolaevich Efimov

    2014-11-01

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

  11. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-12-01

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

  13. Turbulent impinging flow simulation for high-level waste storage and processing applications

    International Nuclear Information System (INIS)

    The efficient storage and processing of high-level nuclear waste could be improved by a better understanding of the behaviour of the particle-laden fluid flows involved. This work reports a mathematical modeling study of impinging single and two-phase turbulent jets that is of relevance to the flows used industrially to prevent the settling of solid particles in storage tanks, and to re-suspend particles that form a bed. A computational fluid dynamic model, that embodies a Lagrangian particle tracking technique, is applied to the prediction of these flows. Predictions in the free flow and wall regions, and along the stagnation line, of the single phase flow are in reasonable accord with data, although the addition of particles results in less satisfactory agreement between predictions and measurements. The influence of particles is, however, reproduced qualitatively by the mathematical model, with quantitative differences attributable to a lack of particle drag in the simulations. Uncertainties in experimental parameters may be responsible for some of the differences between predictions and data, and examination of the data used casts doubts on its reliability. Further work is required in terms of the use of more advanced turbulence modeling techniques, and the provision of detailed and reliable data sets. (authors)

  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. Flow-Dependent Entrapment of Large Bioparticles in Porous Process Media

    Science.gov (United States)

    Trilisky, Egor I.; Lenhoff, Abraham M.

    2009-01-01

    The need for purification of biomolecules extends to larger bioparticles as well. For example, virus purification is required for production of many vaccines and gene delivery vectors, and understanding virus removal in porous media is also important in downstream processing of therapeutic proteins and in purification of water in soils. A convective entrapment mechanism for retention of large bioparticles is discussed here based on retention of large bioparticles in pore constrictions at high enough flow rates, even under non-binding conditions. A simple equation to predict whether such entrapment is expected to occur in a given system is derived based on a Péclet number that is proportional to the flow rate and to the cube of the bioparticle diameter. To test the theory, adenovirus was spiked onto chromatographic beds. As expected from the theory, under non-interacting conditions a progressively larger amount of virus becomes trapped with increasing flow rate. The entrapment is reversible upon flow rate reduction, which, within the proposed model, is based on the possibility of diffusive escape from pore constrictions. This mechanism can be exploited for virus purification or removal, and the theory also explains the anecdotal evidence that monoliths and membranes are more difficult to clean than conventional chromatographic beds, especially at high flow rates. PMID:19459138

  16. 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.

  17. Large Eddy Simulation of Transient Flow, Solidification, and Particle Transport Processes in Continuous-Casting Mold

    Science.gov (United States)

    Liu, Zhongqiu; Li, Linmin; Li, Baokuan; Jiang, Maofa

    2014-07-01

    The current study developed a coupled computational model to simulate the transient fluid flow, solidification, and particle transport processes in a slab continuous-casting mold. Transient flow of molten steel in the mold is calculated using the large eddy simulation. An enthalpy-porosity approach is used for the analysis of solidification processes. The transport of bubble and non-metallic inclusion inside the liquid pool is calculated using the Lagrangian approach based on the transient flow field. A criterion of particle entrapment in the solidified shell is developed using the user-defined functions of FLUENT software (ANSYS, Inc., Canonsburg, PA). The predicted results of this model are compared with the measurements of the ultrasonic testing of the rolled steel plates and the water model experiments. The transient asymmetrical flow pattern inside the liquid pool exhibits quite satisfactory agreement with the corresponding measurements. The predicted complex instantaneous velocity field is composed of various small recirculation zones and multiple vortices. The transport of particles inside the liquid pool and the entrapment of particles in the solidified shell are not symmetric. The Magnus force can reduce the entrapment ratio of particles in the solidified shell, especially for smaller particles, but the effect is not obvious. The Marangoni force can play an important role in controlling the motion of particles, which increases the entrapment ratio of particles in the solidified shell obviously.

  18. Coupled turbulent flow, heat, and solute transport in continuous casting processes

    Science.gov (United States)

    Aboutalebi, M. Reza; Hasan, M.; Guthrie, R. I. L.

    1995-08-01

    A fully coupled fluid flow, heat, and solute transport model was developed to analyze turbulent flow, solidification, and evolution of macrosegregation in a continuous billet caster. Transport equations of total mass, momentum, energy, and species for a binary iron-carbon alloy system were solved using a continuum model, wherein the equations are valid for the solid, liquid, and mushy zones in the casting. A modified version of the low-Reynolds number k-? model was adopted to incorporate turbulence effects on transport processes in the system. A control-volume-based finite-difference procedure was employed to solve the conservation equations associated with appropriate boundary conditions. Because of high nonlinearity in the system of equations, a number of techniques were used to accelerate the convergence process. The effects of the parameters such as casting speed, steel grade, nozzle configuration on flow pattern, solidification profile, and carbon segregation were investigated. From the computed flow pattern, the trajectory of inclusion particles, as well as the density distribution of the particles, was calculated. Some of the computed results were compared with available experimental measurements, and reasonable agreements were obtained.

  19. Modifications to the Conduit Flow Process Mode 2 for MODFLOW-2005.

    Science.gov (United States)

    Reimann, Thomas; Birk, Steffen; Rehrl, Christoph; Shoemaker, W Barclay

    2012-01-01

    As a result of rock dissolution processes, karst aquifers exhibit highly conductive features such as caves and conduits. Within these structures, groundwater flow can become turbulent and therefore be described by nonlinear gradient functions. Some numerical groundwater flow models explicitly account for pipe hydraulics by coupling the continuum model with a pipe network that represents the conduit system. In contrast, the Conduit Flow Process Mode 2 (CFPM2) for MODFLOW-2005 approximates turbulent flow by reducing the hydraulic conductivity within the existing linear head gradient of the MODFLOW continuum model. This approach reduces the practical as well as numerical efforts for simulating turbulence. The original formulation was for large pore aquifers where the onset of turbulence is at low Reynolds numbers (1 to 100) and not for conduits or pipes. In addition, the existing code requires multiple time steps for convergence due to iterative adjustment of the hydraulic conductivity. Modifications to the existing CFPM2 were made by implementing a generalized power function with a user-defined exponent. This allows for matching turbulence in porous media or pipes and eliminates the time steps required for iterative adjustment of hydraulic conductivity. The modified CFPM2 successfully replicated simple benchmark test problems. PMID:21371024

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

    International Nuclear Information System (INIS)

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

  1. Supporting UML Sequence Diagrams with a Processor Net Approach

    Directory of Open Access Journals (Sweden)

    Tony Spiteri Staines

    2007-08-01

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

  2. An evaluation of the rate-controlling flow process in Newtonian creep of polycrystalline ice

    International Nuclear Information System (INIS)

    Using experimental data and theoretical calculation for Newtonian creep in polycrystalline ice, it is demonstrated that unlike most other materials, in which the rate-controlling flow process is edge dislocation climb under saturated condition, the rate-controlling flow process of polycrystalline ice is dislocation glide along the basal plane under a constant dislocation density. The dislocation density during Newtonian creep of ice is determined by the initial state instead of the magnitude of the Peierls stress. The transition stress (threshold) from power-law creep to Newtonian creep is controlled by the dislocation density instead of the Peierls stress. The activation energy of the Newtonian creep is similar to that of the self-diffusion due to the requirements of the diffusion of protons during dislocation glide

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

    OpenAIRE

    Fei Simiao; Li Zheng; Huo Lin

    2013-01-01

    As Hybrid Flow Shops (HFS) are common manufacturing environments, availability of HFS is a basic indicator for measuring usage ability. Optimal maintenance strategy which achieves maximum availability with cost constraints, provides a better platform for its scheduling problems. We propose an availability model in this study by using Semi-Markov Process (SMP) under a general maintenance strategy which suit for general distribution of machines’ life time d...

  4. PROCESS FLOW FOR CLASSIFICATION AND CLUSTERING OF FRUIT FLY GENE EXPRESSION PATTERNS

    OpenAIRE

    Heffel, Andreas; Stadler, Peter F.; Prohaska, Sonja J.; Kauer, Gerhard; Kuska, Jens-Peer

    2008-01-01

    The rapidly growing collection of fruit fly embryo images makes automated Image Segmentation and classification an indispensable requirement for a large-scale analysis of in situ hybridization (ISH) – gene expression patterns (GEP). We present here such an automated process flow for Segmenting, Classification, and Clustering large-scale sets of Drosophila melanogaster GEP that is capable of dealing with most of the complications implicated in the images.

  5. PROCESS FLOW FOR CLASSIFICATION AND CLUSTERING OF FRUIT FLY GENE EXPRESSION PATTERNS

    Science.gov (United States)

    Heffel, Andreas; Stadler, Peter F.; Prohaska, Sonja J.; Kauer, Gerhard; Kuska, Jens-Peer

    2009-01-01

    The rapidly growing collection of fruit fly embryo images makes automated Image Segmentation and classification an indispensable requirement for a large-scale analysis of in situ hybridization (ISH) – gene expression patterns (GEP). We present here such an automated process flow for Segmenting, Classification, and Clustering large-scale sets of Drosophila melanogaster GEP that is capable of dealing with most of the complications implicated in the images. PMID:20046820

  6. Process Monitoring of Continuous Flow Organic Syntheses by means of Inline Fiber Optical Raman Spectroscopy

    OpenAIRE

    Rehman, Muhammas Saif Ur

    2010-01-01

    The objective of the current study was to investigate the feasibility of the inline optical fiber Raman spectroscopy as a tool for the process monitoring of the continuous flow organic syntheses. The synthesis of 2-bromo-3,4,5- trimethoxytoluene (product) was studied as a model reaction under a set of different conditions. The reaction was carried out under the batch as well as in the multi jet oscillating disc (MJOD) milli reactor. The reaction was varied by doubli...

  7. 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

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

    OpenAIRE

    W. Piekarska; KUBIAK, M.

    2009-01-01

    Mathematical and numerical model of the temperature field and the velocity field in melted zone concerning the hybrid laser – arc process was presented in this paper. The temperature field was determined by solution the transient heat transfer equation with activity of inner heat sources. Fluid flow in welding pool was determined by solution of the Navier – Stokes equation in Chorin’s projection. The fuzzy solidification front was assumed in a numerical algorithm with linear approximati...

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

    Science.gov (United States)

    Hung, R. J.

    1995-01-01

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

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

    OpenAIRE

    Villette, S.; Ge?e, C.; Piron, E.; 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 ...

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

    International Nuclear Information System (INIS)

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

  12. 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 ...

  13. 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.

  14. Flows

    OpenAIRE

    Koskas, Michel; Murat, Cecile

    2006-01-01

    Some tools used in Combinatorics of Words allow the profiling of “divide and conquer” algorithms in a number of Operational Research fields, like database management, automatic translation, image pattern recognition, flowing or shortest path problems. . . . This paper details one of them, the maximization of a flow over a network.

  15. The sample processing time interval as an influential factor in flow cytometry analysis of lymphocyte subsets

    Scientific Electronic Library Online (English)

    Ana Paula dos, Santos; Álvaro Luiz, Bertho; Reinaldo de Menezes, Martins; Rugimar, Marcovistz.

    2007-02-01

    Full Text Available The objective of this paper is to propose a protocol to analyze blood samples in yellow fever 17DD vaccinated which developed serious adverse events. We investigated whether or not the time between sample collection and sample processing could interfere in lymphocyte subset percentage, for it is oft [...] en impossible to analyze blood samples immediately after collection due to transport delay from collection places to the flow cytometry facility. CD4+CD38+ T, CD8+CD38+ T, CD3+ T, CD19+ B lymphocyte subsets were analyzed by flow cytometry in nine healthy volunteers immediately after blood collection and after intervals of 24 and 48 h. The whole blood lysis method and gradient sedimentation by Histopaque were applied to isolate peripheral blood mononuclear cells for flow cytometry analyses. With the lysis method, there was no significant change in lymphocyte subset percentage between the two time intervals (24 and 48 h). In contrast, when blood samples were processed by Histopaque gradient sedimentation, time intervals for sample processing influenced the percentage in T lymphocyte subsets but not in B cells. From the results obtained, we could conclude that the whole blood lysis method is more appropriate than gradient sedimentation by Histopaque for immunophenotyping of blood samples collected after serious adverse events, due to less variation in the lymphocyte subset levels with respect to the time factor.

  16. Influence of the gas mixture flow on the processing parameters of hollow cathode discharge iron sintering

    Science.gov (United States)

    Brunatto, S. F.; Muzart, Joel L. R.

    2007-07-01

    A study was made to verify the influence of the gas mixture flow on the iron sintering process with simultaneous surface enrichment of alloying elements by hollow cathode discharge. In this process, two independent cathodes formed an annular discharge: (1) a pressed cylindrical sample of iron powder, acting as the central cathode, was placed concentrically inside an external (hollow) cathode; (2) the external cathode, machined from a AISI 310 steel bar, acted both to confine the geometry of the plasma and as a source of alloying elements (Cr and Ni). The sintering was carried out at 1423 K, for a period of 7.2 × 103 s, under a gas mixture of 80% Ar + 20% H2 and a pressure of 399 Pa, at flow rates of 2 × 10-6, 5 × 10-6, and 8 × 10-6 m3 s-1, with an inter-cathode radial space of 5.8 mm. The discharge was generated using a pulsed voltage power source with a 200 µs period. The gas mixture flow plays an important role both in the cleanliness of the sintering atmosphere (reflected in the electric power utilized to maintain the sample's temperature) and in the amount of metallic atoms deposited on the sample's surface (as a result of the sputtering and the oxidation/reduction process on the cathode surfaces).

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

    Science.gov (United States)

    Muley, Pranjali D; Boldor, Dorin

    2012-01-01

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

  18. 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.

  19. Stochastic flows for L\\'evy processes with H\\"{o}lder drifts

    OpenAIRE

    Chen, Zhen-Qing; Song, Renming; Zhang, Xicheng

    2015-01-01

    In this paper we study the following stochastic differential equation (SDE) in ${\\mathbb R}^d$: $$ \\mathrm{d} X_t= \\mathrm{d} Z_t + b(t, X_t)\\mathrm{d} t, \\quad X_0=x, $$ where $Z$ is a L\\'evy process. We show that for a large class of L\\'evy processes ${Z}$ and H\\"older continuous drift $b$, the SDE above has a unique strong solution for every starting point $x\\in{\\mathbb R}^d$. Moreover, these strong solutions form a $C^1$-stochastic flow. As a consequence, we show that, w...

  20. Fully automated digital holographic processing for monitoring the dynamics of a vesicle suspension under shear flow

    Science.gov (United States)

    Minetti, Christophe; Podgorski, Thomas; Coupier, Gwennou; Dubois, Frank

    2014-01-01

    We investigate the dynamics of a vesicle suspension under shear flow between plates using DHM with a spatially reduced coherent source. Holograms are grabbed at a frequency of 24 frames/sec. The distribution of the vesicle suspension is obtained after numerical processing of the digital holograms sequence resulting in a 4D distribution. Obtaining this distribution is not straightforward and requires special processing to automate the analysis. We present an original method that fully automates the analysis and provides distributions that are further analyzed to extract physical properties of the fluid. Details of the numerical implementation, as well as sample experimental results are presented. PMID:24877015

  1. Flow chemistry: intelligent processing of gas-liquid transformations using a tube-in-tube reactor.

    Science.gov (United States)

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

    2015-02-17

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

  2. Warped penguin diagrams

    Science.gov (United States)

    Csáki, Csaba; Grossman, Yuval; Tanedo, Philip; Tsai, Yuhsin

    2011-04-01

    We present an analysis of the loop-induced magnetic dipole operator in the Randall-Sundrum model of a warped extra dimension with anarchic bulk fermions and an IR brane-localized Higgs. These operators are finite at one-loop order and we explicitly calculate the branching ratio for ??e? using the mixed position/momentum space formalism. The particular bound on the anarchic Yukawa and Kaluza-Klein (KK) scales can depend on the flavor structure of the anarchic matrices. It is possible for a generic model to either be ruled out or unaffected by these bounds without any fine-tuning. We quantify how these models realize this surprising behavior. We also review tree-level lepton flavor bounds in these models and show that these are on the verge of tension with the ??e? bounds from typical models with a 3 TeV Kaluza-Klein scale. Further, we illuminate the nature of the one-loop finiteness of these diagrams and show how to accurately determine the degree of divergence of a five-dimensional loop diagram using both the five-dimensional and KK formalism. This power counting can be obfuscated in the four-dimensional Kaluza-Klein formalism and we explicitly point out subtleties that ensure that the two formalisms agree. Finally, we remark on the existence of a perturbative regime in which these one-loop results give the dominant contribution.

  3. Boolean Expression Diagrams

    DEFF Research Database (Denmark)

    Andersen, Henrik Reif; Hulgaard, Henrik

    1997-01-01

    This paper presents a new data structure called Boolean Expression Diagrams (BEDs) for representing and manipulating Boolean functions. BEDs are a generalization of Binary Decision Diagrams (BDDs) which can represent any Boolean circuit in linear space and still maintain many of the desirable properties of BDDs. Two algorithms are described for transforming a BED into a reduced ordered BDD. One closely mimics the BDD apply-operator while the other can exploit the structural information of the Boolean expression. The efficacy of the BED representation is demonstrated by verifying that the redundant and non-redundant versions of the ISCAS 85 benchmark circuits are identical. In particular, it is verified that the two 16-bit multiplication circuits (c6288 and c6288nr) implement the same Boolean functions. Using BEDs, this verification problem is solved in less than a second, while using standard BDD techniques this problem is infeasible. BEDs are useful in applications where the end-result as a reduced ordered BDD is small, for example for tautology checking

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

    Directory of Open Access Journals (Sweden)

    Baskar A

    2014-11-01

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

  5. 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.?

  6. Fractal-Markovian scaling of turbulent bursting process in open channel flow

    International Nuclear Information System (INIS)

    The turbulent coherent structure of flow in open channel is a chaotic and stochastic process in nature. The coherence structure of the flow or bursting process consists of a series of eddies with a variety of different length scales and it is very important for the entrainment of sediment particles from the bed. In this study, a fractal-Markovian process is applied to the measured turbulent data in open channel. The turbulent data was measured in an experimental flume using three-dimensional acoustic Doppler velocity meter (ADV). A fractal interpolation function (FIF) algorithm was used to simulate more than 500,000 time series data of measured instantaneous velocity fluctuations and Reynolds shear stress. The fractal interpolation functions (FIF) enables to simulate and construct time series of u', v', and u'v' for any particular movement and state in the Markov process. The fractal dimension of the bursting events is calculated for 16 particular movements with the transition probability of the events based on 1st order Markov process. It was found that the average fractal dimensions of the streamwise flow velocity (u') are; 1.73, 1.74, 1.71 and 1.74 with the transition probability of 60.82%, 63.77%, 59.23% and 62.09% for the 1-1, 2-2, 3-3 and 4-4 movements, respectively. It was also found that the fractal dimensions of Reynold stress u'v' for quadrants 1, 2, 3 and 4 are 1.623, 1.623, 1.625 and 1.618, respectively

  7. 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.

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

    DEFF Research Database (Denmark)

    2011-01-01

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

  9. FPGA Implementations of Ladder Diagrams

    Directory of Open Access Journals (Sweden)

    Neil William Bergmann

    2013-02-01

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

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

    Science.gov (United States)

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

    2012-04-01

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

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

    Science.gov (United States)

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

    2012-12-01

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

  12. Generating function for web diagrams

    OpenAIRE

    Vladimirov, A. A.

    2014-01-01

    We present the description of the exponentiated diagrams in terms of generating function within the universal diagrammatic technique. In particular, we show the exponentiation of the gauge theory amplitudes involving products of an arbitrary number of Wilson lines of arbitrary shapes, which generalizes the concept of web diagrams. The presented method gives a new viewpoint on the web diagrams and proves the non-Abelian exponentiation theorem.

  13. The category of Bratteli diagrams

    OpenAIRE

    Amini, Massoud; Elliott, George A.; Golestani, Nasser

    2014-01-01

    A category structure for Bratteli diagrams is proposed and a functor from the category of AF algebras to the category of Bratteli diagrams is constructed. Since isomorphism of Bratteli diagrams in this category coincides with Bratteli's notion of equivalence, we obtain in particular a functorial formulation of Bratteli's classification of AF algebras (and at the same time, of Glimm's classification of UHF algebras). It is shown that the three approaches to classification of ...

  14. Bratteli diagrams: structure, measures, dynamics

    OpenAIRE

    Bezuglyi, S.; Karpel, O.

    2015-01-01

    This paper is a survey on general (simple and non-simple) Bratteli diagrams which focuses on the following topics: finite and infinite tail invariant measures on the path space $X_B$ of a Bratteli diagram $B$, existence of continuous dynamics on $X_B$ compatible with tail equivalence relation, subdiagrams and measure supports. We also discuss the structure of Bratteli diagrams, orbit equivalence and full groups, homeomorphic measures.

  15. Case study: Class diagram restructuring

    OpenAIRE

    Lano, K.; Kolahdouz Rahimi, S.

    2013-01-01

    This case study is an update-in-place refactoring transformation on UML class diagrams. Its aim is to remove clones of attributes from a class diagram, and to identify new classes which abstract groups of classes that share common data features. It is used as one of a general collection of transformations (such as the removal of redundant inheritance, or multiple inheritance) which aim to improve the quality of a specification or design level class diagram. The transf...

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

    International Nuclear Information System (INIS)

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

  17. Conjunctive use of isotopic techniques to elucidate solute concentration and flow processes in dryland salinized catchments

    International Nuclear Information System (INIS)

    A range of isotopic techniques and geochemical methods has been used to investigate the mechanisms of solute concentration and surface and groundwater flow processes in selected small (2) catchments in New South Wales, Australia. The catchments were selected for study as they are typical of the dryland salinized catchments in the region. Environmental isotopes used include the radioactive isotopes 238U and its decay product 234U, 36Cl, tritium (3H), and the stable isotopes deuterium (2H), 18O, and 13C. Stream hydrograph separation based on deuterium and chloride concentrations was used to study stream flow generation and to estimate the extent of salt export from the catchments. Results from the study have provided considerable insight into likely recharge zones and dominant salt concentration mechanisms, and have proved useful in the 'fingerprinting' of particular groundwater provenances. In addition, stream hydrograph separation using isotopic techniques have provided an insight into sources of stream flow generation and the rate and flow path of water (and salt) movement to streams following rainfall events. These are factors that could be managed by alteration in land use practices in these catchments. (author). 17 refs, 10 figs, 2 tabs

  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. 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)

  20. River flow forecasting with artificial neural networks using satellite observed precipitation pre-processed with flow length and travel time information: case study of the Ganges river basin

    Directory of Open Access Journals (Sweden)

    M. K. Akhtar

    2009-09-01

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

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

    Directory of Open Access Journals (Sweden)

    M. K. Akhtar

    2009-04-01

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

  2. 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.

  3. 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.

  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. A transputer-based measuring system for decentralized signal processing, applied to two-phase flow

    Science.gov (United States)

    Schmitt, A.; Hoffmann, K.; Loth, R.

    1995-10-01

    An innovative concept for decentralized processing of the signals of multiple sensors is presented. The basic idea is to connect every sensor via an analog-to-digital converter with a high-performance microprocessor, a transputer, that exclusively collects and processes its signal. The transputers are linked to a powerful network. Exemplarily, a measuring system based on this concept was used for the determination of local parameters of liquid-gas two-phase flows (e.g., local void fraction and bubble frequency). Up to six fiber-optical probes were utilized simultaneously to demonstrate the efficiency of the system. The signal processing under that special application may include on-line evaluation of flow parameters and on-line correction of errors of measurement due to sensor-induced effects. The concept of the new system, however, is basically independent of the number and type of sensors, as well as of the method of signal processing. The transputer-based measuring system thus provides a flexible, efficient tool for applications in which great amounts of data have to be evaluated or manipulated quickly.

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

    International Nuclear Information System (INIS)

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

  8. 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.

  9. 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)

  10. 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

  11. Assessment of ploidy stability of the somatic embryogenesis process in Quercus suber L. using flow cytometry.

    Science.gov (United States)

    Loureiro, J; Pinto, G; Lopes, T; Dolezel, J; Santos, C

    2005-08-01

    Flow cytometry analyses were used to verify the ploidy stability of Quercus suber L. somatic embryogenesis process. Leaf explants of two adult cork oak trees (QsG0 and QsG5) of the North of Portugal were inoculated on MS medium with 2,4-D and zeatin. After 3 months, calluses with embryogenic structures were isolated and transferred to fresh MS medium without growth regulators and somatic embryo evolution was followed. Morphologically normal somatic embryos (with two cotyledons) and abnormal somatic embryos (with one or three cotyledons) were used in this assay. Flow cytometry combined with propidium iodide staining was employed to estimate DNA ploidy levels and nuclear DNA content of somatic embryos and leaves from mother plants. No significant differences (Pcork oak using somatic embryogenesis was assured at this level. The estimation of the 2C nuclear DNA content for this species is similar to the previously obtained value. PMID:15744492

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

    Directory of Open Access Journals (Sweden)

    W. Piekarska

    2009-07-01

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

  13. XLOOPS -- A Program Package calculating One- and Two-Loop Feynman Diagrams

    OpenAIRE

    Brücher, L.; Franzkowski, J.; D. Kreimer

    1997-01-01

    The aim of XLOOPS is to calculate one-particle irreducible Feynman diagrams with one or two closed loops for arbitrary processes in the Standard model of particles and related theories. Up to now this aim is realized for all one-loop diagrams with at most three external lines and for two-loop diagrams with two external lines.

  14. Simulation of drop deposition process in annular mist flow using three-dimensional particle method

    International Nuclear Information System (INIS)

    The three-dimensional moving particle semi-implicit (MPS) method is employed to simulate the deposition process of single droplet on the liquid film. The model accounts for the presence of inertial, gravitation, viscous and surface tension and is validated by comparison with experimental results. The parameters of liquid droplets and film are calculated by a one-dimensional mixture model in which correlations and methods on void fraction, entrainment fraction and droplet velocity and size distribution are employed. The simulation results are analyzed to study the effect of splash on the deposition and re-entrainment processes in annular-mist flow. It is found that splash plays an important role in the deposition and re-entrainment processes in high quality conditions of BWR

  15. Penguin-like Diagrams from the Standard Model

    OpenAIRE

    Chia, Swee-Ping

    2015-01-01

    The Standard Model is highly successful in describing the interactions of leptons and quarks. There are, however, rare processes that involve higher order effects in electroweak interactions. One specific class of processes is the penguin-like diagram. Such class of diagrams involves the neutral change of quark flavours accompanied by the emission of a gluon (gluon penguin), a photon (photon penguin), a gluon and a photon (gluon-photon penguin), a Z-boson (Z penguin), or a H...

  16. 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.

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

    International Nuclear Information System (INIS)

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

  18. 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

  19. 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.

  20. 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.

  1. 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.

  2. Penguin-like diagrams from the standard model

    Science.gov (United States)

    Ping, Chia Swee

    2015-04-01

    The Standard Model is highly successful in describing the interactions of leptons and quarks. There are, however, rare processes that involve higher order effects in electroweak interactions. One specific class of processes is the penguin-like diagram. Such class of diagrams involves the neutral change of quark flavours accompanied by the emission of a gluon (gluon penguin), a photon (photon penguin), a gluon and a photon (gluon-photon penguin), a Z-boson (Z penguin), or a Higgs-boson (Higgs penguin). Such diagrams do not arise at the tree level in the Standard Model. They are, however, induced by one-loop effects. In this paper, we present an exact calculation of the penguin diagram vertices in the `tHooft-Feynman gauge. Renormalization of the vertex is effected by a prescription by Chia and Chong which gives an expression for the counter term identical to that obtained by employing Ward-Takahashi identity. The on-shell vertex functions for the penguin diagram vertices are obtained. The various penguin 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.

  3. 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.

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

    Science.gov (United States)

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

    2014-09-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-07-01

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

  6. Perturbations to the Hubble diagram

    OpenAIRE

    Schucker, Thomas; Zouzou, Ilhem

    2005-01-01

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

  7. Cohomology of diagrams of algebras

    OpenAIRE

    Robinson, Michael

    2008-01-01

    We consider cohomology of diagrams of algebras by Beck's approach, using comonads. We then apply this theory to computing the cohomology of $\\Psi$-rings. Our main result is that there is a spectral sequence connecting the cohomology of the diagram of an algebra to the cohomology of the underlying algebra.

  8. 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...

  9. 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

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

    Directory of Open Access Journals (Sweden)

    Parthasarathy P. R.

    2004-01-01

    Full Text Available 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 state space is infinite is also discussed. Graphs are presented to visualize the buffer content distribution.

  11. Transformations of triangle ladder diagrams

    Science.gov (United States)

    Kondrashuk, Igor; Vergara, Alvaro

    2010-03-01

    It is shown how dual space diagrammatic representation of momentum integrals corresponding to triangle ladder diagrams with an arbitrary number of rungs can be transformed to half-diamonds. In paper arXiv:0803.3420 [hep-th] the half-diamonds were related by conformal integral substitution to the diamonds which represent the dual space image of four-point ladder integrals in the four-dimensional momentum space. Acting in the way described in the present paper we do not need to use the known result for diamond (four-point) diagrams as an external input in deriving relations of arXiv:0803.3420 [hep-th], however, that result for the diamond diagram arises in the present proof as an intermediate consequence in a step-by-step diagrammatic transformation from the triangle ladder diagram to the half-diamond diagrams.

  12. 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

  13. 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...

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

    OpenAIRE

    Unger, J. P.; B Marchal; Dugas, S.; Wuidar, M. J.; Burdet, D.; Leemans, P.; Unger, J.

    2004-01-01

    OBJECTIVES: This case study aims to demonstrate the method's feasibility and capacity to improve quality of care. Several drawbacks attached to tracer condition and selected procedure audits oblige clinicians to rely on external evaluators. Interface flow process audit is an alternative method, which also favours integration of health care across institutions divide. METHODS: An action research study was carried out to test the feasibility of interface flow process audit and its impact on qua...

  15. Experiment and analysis on the flow process dynamics of the NASA-Langley eight foot transonic pressure tunnel

    Science.gov (United States)

    Tcheng, P.

    1977-01-01

    A dynamic response test performed in a eight foot transonic pressure tunnel is described. The dynamics of the flow process of the wind tunnel at transonic conditions were obtained. Descriptions of the test conditions, instrumentation, presentation of raw data, analysis of data, and finally, based on experimental evidences, an attempt to construct an input output relationship of the flow process from the viewpoints of control engineering are included.

  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. 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.

  18. Determination of sulfate in the wet-process of phosphoric acid by reverse flow injection

    Scientific Electronic Library Online (English)

    Wenhui, Shi; Lin, Yang; Quanjun, Fu; Zhiye, Zhang; Xinlong, Wang.

    1357-13-01

    Full Text Available 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.

  19. 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

  20. 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

  1. Performance Analysis Of Various Anti-Reset Windup Algorithms For A Flow Process Station

    Directory of Open Access Journals (Sweden)

    Shaunak Chakrabartty

    2014-05-01

    Full Text Available The study was aimed to develop the various aspects of Anti reset windup or Integral windup and also the different algorithms available to eliminate the phenomenon of windup. Different open loop responses were obtained from a Flow process Station using MATLAB and SIMULINK and VI Microsystems process control software. The open loop responses were evaluated and different system models were generated using the two point method. The system models were found to follow a decreasing order of Gain values and an increasing order of Td and T values. A SIMULINK model was obtained to implement Back calculation combined with Conditional Integration. The models for the system obtained were simulated using the SIMULINK model and a PID controller and the closed loop responses were generated. The closed loop responses using a PID controller with Back calculation and Conditional integration were found to follow the set point as expected.

  2. 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)

  3. 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.

  4. Modeling of the flow continuum and optimal design of control-oriented injection systems in liquid composite molding processes

    Science.gov (United States)

    Gokce, Ali

    Several methodologies are presented in this dissertation that aim to ensure successful filling of the mold cavity consistently, during the mold filling stage of Liquid Composite Molding (LCM) processes such as Resin Transfer Molding (RTM), Vacuum Assisted Resin Transfer Molding (VARTM) and Seemann Composites Resin Infusion Molding (SCRIMP). Key parameters that affect the resin flow in the mold cavity can be divided into two main groups as continuum-related parameters and injection-related parameters. Flow continuum, which consists of all the spaces resin can reach in the mold cavity, has two major components: the porous medium, which is made up of the fiber reinforcements, and the flow channels that are introduced into the flow continuum unintentionally and offer an easy flow path to the resin. The properties that characterize the porous medium and the unintentional flow channels are continuum-related parameters. The injection-related parameters include resin injection locations (gates), resin injection conditions and air drainage locations (vents). Modeling the flow continuum is crucial in predicting the resin flow in the mold cavity. In this study, permeability, the key property of the porous medium, is predicted using the Method of Cells, a proven method to predict macroscopic properties of heterogeneous materials. Unintentional flow channels, which are also called racetracking channels, are modeled using a probabilistic approach. Injection-related parameters are the key tools to influence the resin flow in the mold cavity. In this study, Branch and Bound Search is modified for single gate optimization. Due to its pertinence to injection system design, the parameters that govern gate effectiveness in steering the resin advance are studied. A combinatorial search algorithm is proposed for vent optimization. Vent optimization and gate optimization algorithms are integrated for simultaneous gate and vent optimization. Overall, these methodologies reduce the cycle time and reject ratio of LCM processes by providing an accurate and complete model of the flow continuum and optimal control-oriented injection design solutions, increasing the profitability and feasibility of the process.

  5. Toxic metals in WEEE: characterization and substance flow analysis in waste treatment processes.

    Science.gov (United States)

    Oguchi, Masahiro; Sakanakura, Hirofumi; Terazono, Atsushi

    2013-10-01

    Waste electrical and electronic equipment (WEEE) has received extensive attention as a secondary source of metals. Because WEEE also contains toxic substances such as heavy metals, appropriate management of these substances is important in the recycling and treatment of WEEE. As a basis for discussion toward better management of WEEE, this study characterizes various types of WEEE in terms of toxic metal contents. The fate of various metals contained in WEEE, including toxic metals, was also investigated in actual waste treatment processes. Cathode-ray tube televisions showed the highest concentration and the largest total amount of toxic metals such as Ba, Pb, and Sb, so appropriate recycling and disposal of these televisions would greatly contribute to better management of toxic metals in WEEE. A future challenge is the management of toxic metals in mid-sized items such as audio/visual and ICT equipment because even though the concentrations were not high in these items, the total amount of toxic metals contained in them is not negligible. In the case of Japan, such mid-sized WEEE items as well as small electronic items are subject to municipal solid waste treatment. A case study showed that a landfill was the main destination of toxic metals contained in those items in the current treatment systems. The case study also showed that changes in the flows of toxic metals will occur when treatment processes are modified to emphasize resource recovery. Because the flow changes might lead to an increase in the amount of toxic metals released to the environment, the flows of toxic metals and the materials targeted for resource recovery should be considered simultaneously. PMID:22921510

  6. Real-time Visualization of Multiphase Flow by Means of Electrical Process Tomography

    Science.gov (United States)

    Choi, Je-Eun; Zhao, Tong; Takei, Masahiro

    A new reconstruction method called Generalized Vector Sampled Pattern Matching (GVSPM) has been applied to an ill-posed inverse problem involving an electrical process tomography for multiphase flow. The characteristics of GVSPM method were examined using a simulation for pseudo particle concentration distribution images. Overall, the GVSPM method was proved superior to the LW and the ITR methods in the case of annular pseudo particle images. Then, a large scale electrical capacitance tomography (ECT) system was designed to visualize the powder concentration in the process of mixing air and FCC catalysts in a vertical pipeline. The concentration distribution image was obtained its accuracy was also discussed systemically. Moreover, another research focused on the fabrication of a micro-channel and the visualization of solid-liquid two phase flow in the micro-channel. A micro-channel with commercial connecter system for 60 electrodes was fabricated. The impedance between the electrodes was measured with changed frequency, and the cross-sectional impedance was determined.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. Para-equilibrium phase diagrams

    International Nuclear Information System (INIS)

    Highlights: • A rapidly cooled system may attain a state of para-equilibrium. • In this state rapidly diffusing elements reach equilibrium but others are immobile. • Application of the Phase Rule to para-equilibrium phase diagrams is discussed. • A general algorithm to calculate para-equilibrium phase diagrams is described. - Abstract: If an initially homogeneous system at high temperature is rapidly cooled, a temporary para-equilibrium state may result in which rapidly diffusing elements have reached equilibrium but more slowly diffusing elements have remained essentially immobile. The best known example occurs when homogeneous austenite is quenched. A para-equilibrium phase assemblage may be calculated thermodynamically by Gibbs free energy minimization under the constraint that the ratios of the slowly diffusing elements are the same in all phases. Several examples of calculated para-equilibrium phase diagram sections are presented and the application of the Phase Rule is discussed. Although the rules governing the geometry of these diagrams may appear at first to be somewhat different from those for full equilibrium phase diagrams, it is shown that in fact they obey exactly the same rules with the following provision. Since the molar ratios of non-diffusing elements are the same in all phases at para-equilibrium, these ratios act, as far as the geometry of the diagram is concerned, like “potential” variables (such as T, pressure or chemical potentials) rather than like “normal” composition variables which need not be the same in all phases. A general algorithm to calculate para-equilibrium phase diagrams is presented. In the limit, if a para-equilibrium calculation is performed under the constraint that no elements diffuse, then the resultant phase diagram shows the single phase with the minimum Gibbs free energy at any point on the diagram; such calculations are of interest in physical vapor deposition when deposition is so rapid that phase separation does not occur

  12. Small examples of cube diagrams of knots

    OpenAIRE

    Baldridge, Scott; McCarty, Ben

    2009-01-01

    In this short note we highlight some of the differences between cube diagrams and grid diagrams. We also list examples of small cube diagrams for all knots up to 7 crossings and give some examples of links.

  13. Particles, Feynman Diagrams and All That

    Science.gov (United States)

    Daniel, Michael

    2006-01-01

    Quantum fields are introduced in order to give students an accurate qualitative understanding of the origin of Feynman diagrams as representations of particle interactions. Elementary diagrams are combined to produce diagrams representing the main features of the Standard Model.

  14. Autoclave processing for composite material fabrication. 1: An analysis of resin flows and fiber compactions for thin laminate

    Science.gov (United States)

    Hou, T. H.

    1985-01-01

    High quality long fiber reinforced composites, such as those used in aerospace and industrial applications, are commonly processed in autoclaves. An adequate resin flow model for the entire system (laminate/bleeder/breather), which provides a description of the time-dependent laminate consolidation process, is useful in predicting the loss of resin, heat transfer characteristics, fiber volume fraction and part dimension, etc., under a specified set of processing conditions. This could be accomplished by properly analyzing the flow patterns and pressure profiles inside the laminate during processing. A newly formulated resin flow model for composite prepreg lamination process is reported. This model considers viscous resin flows in both directions perpendicular and parallel to the composite plane. In the horizontal direction, a squeezing flow between two nonporous parallel plates is analyzed, while in the vertical direction, a poiseuille type pressure flow through porous media is assumed. Proper force and mass balances have been made and solved for the whole system. The effects of fiber-fiber interactions during lamination are included as well. The unique features of this analysis are: (1) the pressure gradient inside the laminate is assumed to be generated from squeezing action between two adjacent approaching fiber layers, and (2) the behavior of fiber bundles is simulated by a Finitely Extendable Nonlinear Elastic (FENE) spring.

  15. Estimated International Energy Flows 2007

    Science.gov (United States)

    Clara Smith

    This Energy Flow Charts website is a set of energy Sankey diagrams or flow charts for 136 countries constructed from data maintained by the International Energy Agency (IEA) and reflects the energy use patterns for 2007.

  16. Standard services for the capture, processing, and distribution of packetized telemetry data

    Science.gov (United States)

    Stallings, William H.

    1989-01-01

    Standard functional services for the capture, processing, and distribution of packetized data are discussed with particular reference to the future implementation of packet processing systems, such as those for the Space Station Freedom. The major functions are listed under the following major categories: input processing, packet processing, and output processing. A functional block diagram of a packet data processing facility is presented, showing the distribution of the various processing functions as well as the primary data flow through the facility.

  17. Scattering Equations and Feynman Diagrams

    CERN Document Server

    Baadsgaard, Christian; Bourjaily, Jacob L; Damgaard, Poul H

    2015-01-01

    We show a direct matching between individual Feynman diagrams and integration measures in the scattering equation formalism of Cachazo, He and Yuan. The connection is most easily explained in terms of triangular graphs associated with planar Feynman diagrams in $\\phi^3$-theory. We also discuss the generalization to general scalar field theories with $\\phi^p$ interactions, corresponding to polygonal graphs involving vertices of order $p$. Finally, we describe how the same graph-theoretic language can be used to provide the precise link between individual Feynman diagrams and string theory integrands.

  18. Phase diagram of polypeptide chains

    Science.gov (United States)

    Auer, Stefan

    2011-11-01

    We use a coarse grained protein model that enables us to determine the equilibrium phase diagram of natively folded ?-helical and unfolded ?-sheet forming peptides. The phase diagram shows that there are only two thermodynamically stable peptide phases, the peptide solution and the bulk fibrillar phase. In addition, it reveals the existence of various metastable peptide phases. The liquidlike oligomeric phases are metastable with respect to the fibrillar phases, and there is a hierarchy of metastability. The presented phase diagram provides a solid basis for understanding the assembly of polypeptide chains into the phases formed in their natively folded and unfolded conformations.

  19. Nonabelian Cut Diagrams and their Applications

    OpenAIRE

    Lam, C. S.

    1996-01-01

    A new kind of cut diagram is introduced to sum Feynman diagrams with nonabelian vertices. Unlike the Cutkosky diagrams which compute the discontinuity of single Feynman diagrams, the nonabelian cut diagrams represent a resummation of both the real and the imaginary parts of Feynman diagrams related by permutations. Several applications of the technique are reported, including a resolution of the apparent inconsistency of the baryon problem in large-$N_c$ QCD, a simplified ca...

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

    International Nuclear Information System (INIS)

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

    International Nuclear Information System (INIS)

    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. (Author).

  2. 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

  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. 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.

  5. Finding and accessing diagrams in biomedical publications.

    Science.gov (United States)

    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 and line charts by the shape and relative location of the different image elements that make up the charts. With recall and precisions of close to 90% for the detection of relevant figures, we discuss the use of this technology in an existing biomedical image search engine, and outline how it enables new forms of literature queries over biomedical relationships that are represented in these charts. PMID:23304318

  6. Phase diagram and edge effects in the ASEP with bottlenecks

    OpenAIRE

    Greulich, Philip; Schadschneider, Andreas

    2007-01-01

    We investigate the totally asymmetric simple exclusion process (TASEP) in the presence of a bottleneck, i.e. a sequence of consecutive defect sites with reduced hopping rate. The influence of such a bottleneck on the phase diagram is studied by computer simulations and a novel analytical approach. We find a clear dependence of the current and the properties of the phase diagram not only on the length of the bottleneck, but also on its position. For bottlenecks near the bound...

  7. 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.

  8. 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 representations of proofs. In addition we note that `visualizaton' is used in different ways. In the first sense visualization denotes our inner mental pictures, which enables us to see that a certain fact holds, whereas in the other sense, `visualization' denotes a diagram or representation of something.

  9. Large deviations in stochastic heat-conduction processes provide a gradient-flow structure for heat conduction

    International Nuclear Information System (INIS)

    We consider three one-dimensional continuous-time Markov processes on a lattice, each of which models the conduction of heat: the family of Brownian Energy Processes with parameter m (BEP(m)), a Generalized Brownian Energy Process, and the Kipnis-Marchioro-Presutti (KMP) process. The hydrodynamic limit of each of these three processes is a parabolic equation, the linear heat equation in the case of the BEP(m) and the KMP, and a nonlinear heat equation for the Generalized Brownian Energy Process with parameter a (GBEP(a)). We prove the hydrodynamic limit rigorously for the BEP(m), and give a formal derivation for the GBEP(a). We then formally derive the pathwise large-deviation rate functional for the empirical measure of the three processes. These rate functionals imply gradient-flow structures for the limiting linear and nonlinear heat equations. We contrast these gradient-flow structures with those for processes describing the diffusion of mass, most importantly the class of Wasserstein gradient-flow systems. The linear and nonlinear heat-equation gradient-flow structures are each driven by entropy terms of the form ?log??; they involve dissipation or mobility terms of order ?2 for the linear heat equation, and a nonlinear function of ? for the nonlinear heat equation

  10. VISUALISATION AND ANALYSIS OF THE FLUID FLOW STRUCTURE INSIDE AN ELLIPTICAL STEELMAKING LADLE THROUGH IMAGE PROCESSING TECHNIQUES

    OpenAIRE

    Nunes, R. P.; Pereira, J. A. M.; Vilela, A. C. F.; Laan, F. T. V.

    2007-01-01

    The understanding of the fluid flow conditions during the liquid steel stirring treatment in the ladle is an important issue to optimize the steelmaking process. In this sense, in this article, a cold physical model in reduced scale of a gas-stirred ladle has been built and investigated through image processing techniques to evaluate its velocity field. The gas has been injected in 3 different positions of the ladle base and the resulted fluid flow has been analyzed by the Image Processing Ve...

  11. Effect of small-scale fractures on flow and transport processes at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Although many conceptual models for fracture-matrix interaction have been evaluated for Yucca Mountain site-characterization studies, the most widely used model is currently based on the dual-permeability concept. It was chosen for use in site-characterization partially because it has proved to be capable of matching many types of field observed data. Another consideration is that net infiltration rates at the site are estimated to be very low (on the order of millimeters/year), or close to saturated matrix hydraulic conductivity. Recent field studies and tests, in particular, fracture mapping data, collected along the walls of the underground tunnels reveal that there exists a significantly large variety in fracture sizes from centimeters to tens of meters. There is a considerable amount of small-scale fractures that have not been considered in the previous modeling studies. Although the majority of these small fractures may not contribute much to global flow and transport through the fracture-matrix system, they may provide large amounts of storage pore space and allow for additional connection areas for well-connected, large-scale fractures and surrounding matrix blocks, which ultimately affect fracture-matrix interactions. However, the currently used dual-permeability model is unable to include the potentially important effect of small fractures. To overcome the limitations of the dual-permeability approach, we have developed a triple-continuum conceptual model to investigate the impact of small-scale fractures on flow and transport processes in fractured rocks. This new conceptual model subdivides fractures into two types: large-scale and small-scale. Large-scale fractures are those responsible for global connections; small-scale fractures are those that provide large-fracture storage space and enhance the local connections to the matrix system without contributing to global flow or transport. Because the triple-continuum model is composed of the rock matrix and two types of fractures, it can be regarded as an extension of the traditional dual-permeability model. Using a generalized triple-continuum approach, the model formulation uses three parallel sets of conservation equations to describe flow and transport processes at each location of the system, for the two-fracture and one-matrix systems, respectively. The proposed triple-continuum model has been implemented using both analytical and numerical approaches and applied to field problems at Yucca Mountain. First we apply the new conceptual model to estimate model-related fracture-matrix parameters using field observation data and inverse modeling approach. Then we incorporate the estimated parameters to perform 3-D site-scale flow and transport simulations with the current hydrogeological model of Yucca Mountain. The 3-D modeling results with the triple-continuum model indicate that small fractures have significant impact on radionuclide transport in the UZ system, while their effects on flow and heat transfer are insignificant

  12. CFD Simulation of the Flow in Jet-swirl Nozzle for Preparing Nano-drug During a SEDS Process

    Directory of Open Access Journals (Sweden)

    Leilei Wang

    2013-01-01

    Full Text Available Solution Enhanced Dispersion by Supercritical fluid (SEDS process is utilized more and more widely for preparing nano-drug. Nozzle is the key component in SEDS process. In this study, the flow in jet-swirl nozzle for preparing nano-drug in SEDS process was analyzed by Computational Fluid Dynamics (CFD. It can be concluded from the results that the jet mixing length was found to be a strong function of the volume flow of supercritical CO2 (SC-CO2 at the inlet of the swirl chamber. When the volume flow of SC-CO2 was equal to or greater than 25 mL min-1, methylene chloride and SC-CO2 mixed completely in the nozzle. These results were coincident with the results obtained from experiments in literature. In additional, it also was indicated that the turbulent intensity at the outlet was all even in different volume flow of SC-CO2 and with the increase of volume flow of SC-CO2, the turbulent intensities at the outlet become greater and greater. These results were similar with the results obtained from experiments in literature. By these CFD analysis and comparison with literature, the flow parameters in jet-swirl nozzle were revealed and the method of CFD analysis for SEDS process was validated.

  13. Visualization of Liquid Metal Two-phase Flows in a Physical Model of the Continuous Casting Process of Steel

    Science.gov (United States)

    Timmel, Klaus; Shevchenko, Natalia; Röder, Michael; Anderhuber, Marc; Gardin, Pascal; Eckert, Sven; Gerbeth, Gunter

    2015-04-01

    We present an experimental study concerned with investigations of the two-phase flow in a mock-up of the continuous casting process of steel. A specific experimental facility was designed and constructed at HZDR for visualizing liquid metal two-phase flows in the mold and the submerged entry nozzle (SEN) by means of X-ray radioscopy. This setup operates with the low melting, eutectic alloy GaInSn as model liquid. The argon gas is injected through the tip of the stopper rod into the liquid metal flow. The system operates continuously under isothermal conditions. First results will be presented here revealing complex flow structures in the SEN widely differing from a homogeneously dispersed bubbly flow. The patterns are mainly dominated by large bubbles and large-area detachments of the liquid metal flow from the inner nozzle wall. Various flow regimes can be distinguished depending on the ratio between the liquid and the gas flow rate. Smaller gas bubbles are produced by strong shear flows near the nozzle ports. The small bubbles are entrained by the submerged jet and mainly entrapped by the lower circulation roll in the mold. Larger bubbles develop by coalescence and ascend toward the free surface.

  14. Development of the flow behavior model for 3D scaffold fabrication in the polymer deposition process by a heating method

    International Nuclear Information System (INIS)

    The flow behavior model for 3D scaffold fabrication in the polymer deposition process by the heating method was developed for enhanced efficiency of the deposition process. The analysis of the polymer flow property is very important in the fabrication process of precise micro-structures such as scaffolds. In this study, a deposition model considering fluid mechanics and heat transfer phenomena was built up and introduced for the estimation of the fluid behavior of molten polymer. The effectiveness of the simulation model was verified through comparison with the experimental result in the case of PCL biomaterial. In addition, the effects of various parameters, such as pressure, temperature and nozzle size, were predicted through simulation before experimental approaches. Through the fabrication of 3D scaffold, it is concluded that this model is useful in predicting the flow behavior characteristics in the micro-structure fabrication process, which is based on the heating method

  15. 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

  16. Introduction to Ternary Phase Diagrams

    Science.gov (United States)

    Dexter Perkins

    This exercise is intended as a group exercise to help students learn the fundamentals of using ternary phase diagrams. It is a much better way for students to learn about the diagrams than to lecture to them. Good students will be able to walk through this with little assistance from the instructor.Weaker students will struggle and need help from peers or instructors. The entire exercise takes 1-2 hours for most.

  17. Interpreting T-X Diagrams

    Science.gov (United States)

    Dexter Perkins

    This short problem set works well as a group activity that can be completed in class. The purpose of the exercise is for students to begin to think about T-X phase diagrams and how they are interpreted. Along the way, students learn that text book authors sometimes make mistakes. The figure in the handout is from Winter's Petrology. But, Winter goofed and left some reactions off of the phase diagram.

  18. Numerical simulation of reactive flow in hot aquifers using SHEMAT and Processing SHEMAT

    Science.gov (United States)

    Clauser, C.; Bartels, J.; Kühn, M.; Pape, H.; Stöfen, H.

    2003-04-01

    This poster introduces a book and the associated software dealing with the numerical simulation of reactive transport in porous media using the simulation package SHEMAT / Processing SHEMAT. The book is a richly documented manual for users of this software which discusses in detail the coded physical and chemical equations. Further, it contains a detailed tutorial which leads the user through all options of the software, a chapter on advanced features, such as chemical reaction modeling for highly saline formation waters and the relation between porosity and permeability changes, and seven application cases, each highlighting different capabilities of the code. Thus the book provides the in-depth background required by those who want to apply the code for solving advanced technical and scientific problems. The software includes user-friendly pre- and post-processors which make it very easy to set up a model, run it and view the results, all from one platform. Therefore the software is also very suitable for academic or technical "hands-on" courses on simulating flow, transport of heat and mass, and chemical reactions in porous media. The enclosed companion CD-ROM contains the program, and all data for all of the case studies. The poster presents the content of the book and shows examples, in particular of the applications to the simulations of non-linear coupled reactive flow problems.

  19. On the mechanism of film flow in the process of steam condensation in horizontal tube bundles

    International Nuclear Information System (INIS)

    The mechanism of condensate film flow over the surface of horizontal pipes, separation from the overlying pipes and their approaching the surface of the lower lying pipes has been experimentally investigated. The tests included visual observation of the process under real conditions. To this end, a test set-up had been created which essentially consisted of a heat exchanger with translucent walls having the condensation surface F=3.14 m4 and composed of 84 cupronickel tubes with dsub(outer)=16mm and active length of 745 mm. The experiments have shown that the manner, in which the condensate flows down from one pipe onto another in a multirow pipe bunch is quite different from the Nousselt scheme. It has been found that in the corridor-type pipe bunches with depth-wise pipe spacing s/d<=1.5, joining of the drops from the overlying and underlying pipes and their rolling round a pipe without apparent spreading throughout the bunch depth are observed. This effect permits to regard the heat transfer intensity from the portion of pipe surfaces where there are no drops approximately equal to the first row intensity

  20. Multiplexed fibre optic sensors for monitoring resin infusion, flow, and cure in composite material processing

    Science.gov (United States)

    Chehura, Edmon; Jarzebinska, Renata; Da Costa, Elisabete F. R.; Skordos, Alexandros A.; James, Stephen W.; Partridge, Ivana K.; Tatam, Ralph P.

    2013-04-01

    The infusion, flow and cure of RTM6 resin in a carbon fibre reinforced composite preform have been monitored using a variety of multiplexed fibre optic sensors. Optical fibre Fresnel sensors and tilted fibre Bragg grating (TFBG) sensors were configured to monitor resin infusion/flow in-plane of the component. The results obtained from the different sensors were in good agreement with visual observations. The degree of cure was monitored by Fresnel sensors via a measurement of the refractive index of the resin which was converted to degree of cure using a calibration determined from Differential Scanning Calorimetry. Fibre Bragg grating sensors fabricated in highly linearly birefringent fibre were used to monitor the development of transverse strain during the cure process, revealing through-thickness material shrinkage of about 712 ?? and residual strain of 223 ??. An alternative approach to infusion monitoring, based on an array of multiplexed tapered optical fibre sensors interrogated using optical frequency domain reflectometry, was also investigated in a separate carbon fibre preform that was infused with RTM6 resin.

  1. The effect of correlated flow in pulsed column contactors using the Purex process

    International Nuclear Information System (INIS)

    The mathematical basis for a new computer code, CUSEP-MOD1, is described. This new code allows the calculation of the temporal response of pulsed column contactors with sieve plates in which spent nuclear fuel is reprocessed using the Purex process. The CPU times needed for these calculations are shorter than those using the CUSEP code but longer than those using the PULSER code, these latter codes having been described previously. Although PULSER remains the faster code, it utilizes approximations that would make CUSEP-MOD1 the preferable code for many applications. The improved efficiency of CUSEP-MOD1 is based on an analysis of the correlation of the aqueous and organic flows in pulsed columns. The analysis shows that both phases move with positive correlation at zero lag time because of the magnitude of the impressed pulsed flow. The new code gives concentration profiles virtually identical to those of the CUSEP code and replaces CUSEP for calculation of the temporal and steady-state concentration profiles in pulsed column contactors. A comparison is made of the steady-state concentration profiles in pulsed column contactors. A comparison is made of the steady-state concentration profiles in an exemplary extraction (A-type) contactor calculated using CUSEP, CUSEP-MOD1, and PULSER

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

    DEFF Research Database (Denmark)

    Tonini, Davide; Woods, M.

    2011-01-01

    Recovery of resources from mixed Municipal Solid Waste (MSW) is a crucial aspect of waste management practices. In this paper the materials and carbon flows of an innovative waste refinery process using enzymes are presented. Through enzymatic treatment the process produces two main streams from the initial mixed MSW: a bioslurry (liquefied paper and organics) and a solid fraction (non-degradable materials). The discussion is based on the performance of the process in separating recyclables and recovery Cbiogenic as well as nutrients from the input MSW. The results of MFA and SFA illustrate that the waste refinery has great potential for resource recovery: about 100% of the Cbiogenic and up to 90% of N and P can potentially be recovered in the bioslurry and returned to land after anaerobic digestion. Recovery of ferrous and non-ferrous material is estimated double compared to recovering the same material from bottom ash after incineration (current scenario). Hard plastic can also be separated and recovered. Potentially, only residual 20% of the initial MSW is to be incinerated after refining and separation of metals and plastic.

  3. Effects of Micromachining Processes on Electro-Osmotic Flow Mobility of Glass Surfaces

    Directory of Open Access Journals (Sweden)

    Norihisa Miki

    2013-03-01

    Full Text Available Silica glass is frequently used as a device material for micro/nano fluidic devices due to its excellent properties, such as transparency and chemical resistance. Wet etching by hydrofluoric acid and dry etching by neutral loop discharge (NLD plasma etching are currently used to micromachine glass to form micro/nano fluidic channels. Electro-osmotic flow (EOF is one of the most effective methods to drive liquids into the channels. EOF mobility is affected by a property of the micromachined glass surfaces, which includes surface roughness that is determined by the manufacturing processes. In this paper, we investigate the effect of micromaching processes on the glass surface topography and the EOF mobility. We prepared glass surfaces by either wet etching or by NLD plasma etching, investigated the surface topography using atomic force microscopy, and attempted to correlate it with EOF generated in the micro-channels of the machined glass. Experiments revealed that the EOF mobility strongly depends on the surface roughness, and therefore upon the fabrication process used. A particularly strong dependency was observed when the surface roughness was on the order of the electric double layer thickness or below. We believe that the correlation described in this paper can be of great help in the design of micro/nano fluidic devices.

  4. 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 irrota, 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)

  5. Structure and Process - Influence of Historical Agriculture of Linear Flow Paths by Extreme Rainfall in Brandenburg

    Directory of Open Access Journals (Sweden)

    Dr. Detlef Deumlich

    2012-12-01

    Full Text Available Long-term erosion forecast can completely misinterpret in extreme events in plain regions. Flow paths are well represented in the plain using digital elevation models in the 1-m grid (DEM1. The scale of the erosion process models and the elevation models is comparable. With it instruments are available to improve the erosion simulation. Simulations, based on (RUSLE family and bigger grid width, are relevant for regional overviews, to the clarification of small scale relevant linear erosion forms, however, unsuitably. The cross-slope tillage has intensified the water erosion in the examined case with special area morphology. From historical sources furrows of the ridge and furrow system were identified as runoff ways. Historical and actual information sources allowed the clarification of especially regional erosion events. Site specific and climatic factors as well as the actual land management caused a high damage magnitude in particular with extreme rainstorms, modified by historical land use structures.

  6. 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.

  7. 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.

  8. Deformation, orientation and bursting of microcapsules in simple shear flow: Wrinkling processes, tumbling and swinging motions

    Science.gov (United States)

    Unverfehrt, A.; Koleva, I.; Rehage, H.

    2015-04-01

    In a series of experiments we studied the deformation and orientation behaviour of microcapsules in simple shear flow. For a large number of capsules we observed folding processes which were induced by the bending resistance, by membrane pre-stresses or the mechanical asymmetry of the surrounding viscoelastic wall materials. Periodic oscillations of the inclination angle were detected for non-spherical particles. At low shear rates a tumbling motion occurred in which the capsule turned around its axis. A swinging mode at evaluated shear rates was accompanied by tank-treading motions, a rotation of the membrane around the capsule core. Between these two well-known motions we also observed an intermittent regime.

  9. Fluctuations and pseudo long range dependence in network flows: A non-stationary Poisson process model

    International Nuclear Information System (INIS)

    In the study of complex networks (systems), the scaling phenomenon of flow fluctuations refers to a certain power-law between the mean flux (activity) (Fi) of the i-th node and its variance ?i as ?i ? (Fi)?. Such scaling laws are found to be prevalent both in natural and man-made network systems, but the understanding of their origins still remains limited. This paper proposes a non-stationary Poisson process model to give an analytical explanation of the non-universal scaling phenomenon: the exponent ? varies between 1/2 and 1 depending on the size of sampling time window and the relative strength of the external/internal driven forces of the systems. The crossover behaviour and the relation of fluctuation scaling with pseudo long range dependence are also accounted for by the model. Numerical experiments show that the proposed model can recover the multi-scaling phenomenon. (general)

  10. Conservação e reúso de águas usando o método Diagrama de Fontes de Água para processos em batelada: estudo de casos / Water conservation and reuse using the Water Sources Diagram method for batch process: case studies

    Scientific Electronic Library Online (English)

    Reinaldo Coelho, Mirre; Shaula Christine Leal, Ferreira; Aline Rodrigues, Dias; Fernando Luiz Pellegrini, Pessoa.

    2012-03-01

    Full Text Available O gerenciamento de recursos hídricos tem sido um fator importante para a sustentabilidade dos processos industriais, visto que há uma necessidade crescente pelo desenvolvimento de metodologias voltadas para conservação e uso racional da água. O objetivo deste trabalho foi aplicar o método Diagrama d [...] e Fontes de Água (DFA), usado na definição de metas de mínimo consumo de água, a processos que operam em regime batelada. Foram gerados e avaliados cenários de reúso de correntes obtidos pela aplicação do método a partir de dados de quantidade de água e concentração de contaminantes nas operações. Foram apresentados dois estudos de caso com o objetivo de demonstrar a redução de consumo de água e da geração de efluentes, além de custos de tratamento final e de investimento em tanques de estocagem, em relação à configuração inicial. Os cenários mostraram-se bastante promissores, com reduções que alcançam 45%, em termos de consumo hídrico e geração de efluentes, e 37%, em termos de custos de tanques, sem a necessidade de processos de regeneração. Com isso, a técnica empregada mostrou-se relevante e flexível como alternativa às ferramentas sistemáticas voltadas para a minimização do consumo de água em processos industriais, exercendo importante papel em um programa de gerenciamento de recursos hídricos. Abstract in english The water resources management has been an important factor for the sustainability of industrial processes, since there is a growing need for the development of methodologies aimed at the conservation and rational use of water. The objective of this work was to apply the heuristic-algorithmic method [...] called Water Sources Diagram (WSD), which is used to define the target of minimum water consumption, to batch processes. Scenarios with reuse of streams were generated and evaluated with application of the method from the data of water quantity and concentration of contaminants in the operations. Two case studies aiming to show the reduction of water consumption and wastewater generation, and final treatment costs besides investment in storage tanks, were presented. The scenarios showed great promising, achieving reduction up to 45% in water consumption and wastewater generation, and a reduction of around 37% on cost of storage tanks, without the need to allocate regeneration processes. Thus, the WSD method showed to be a relevant and flexible alternative regarding to systemic tools aimed at minimizing the consumption of water in industrial processes, playing an important role within a program of water resources management.

  11. Multiphase flow importance in future nuclear process heat applications: energy alcohol by biomass gasification with HTR

    International Nuclear Information System (INIS)

    For future nuclear process heat applications multiphase phenomena are very important in a three-fold sense: For the ability to produce high temperature heat, for the realization of a catastrophe-free nuclear energy technology and for the newly proposed carbondioxide-neutral energy system 'energy alcohol from biomass plus HTR'. The technology of the 'Coated Particle' with the multi-coating of ceramic coatings on microparticles on nuclear fuel for the HTR is the technological reason for the ability to produce high temperature heat from nuclear energy. It is produced by chemical vapour deposition in a fluidized bed, this is a two-phase-fluidized-bed/gaseous-to-solid-states-change by pyrolysis/multi-component/phenomenon. The new requirement of a catastrophe-free nuclear energy technology has led to the identification that the ingress of water droplets into the nuclear core of the HTR should be avoided by self-acting separation of droplets coming from the steam generator tube break before they can get into the core. The behaviour of the water/steam jet in the helium stream is a two-phase-flow/far-from-equilibrium-phase-change/two-component/phenomenon. The biggest challenge to the energy industry is the carbondioxide-climate-change-problem. The solution requires the reduction of the application of fossil primary energy carriers by the factor of about 5 for the world, and e.g. by the factors of about 13 for FRG and about 10 for Japan. As a contribution to the solution a new . As a contribution to the solution a new proposal has been made recently: the production of energy alcohol, e.g. methanol, on the basis 'biomass plus HTR'. The main part of the energy conversion process is the helium-heated fluidized bed steam gasification of biomass. This a two-phase-flow/solid-to-gaseous states-change/pyrolysis and chemical reaction/multi-component/phenomenon. (J.P.N.)

  12. SCIENTIFICAL, TECHNOLOGICAL AND METHODICAL ASPECTS OF EDUCATIONAL PROCESS DOCUMENT FLOW ORGANIZATION IN THE INFORMATIVE SYSTEMS OF INDUSTRY OF EDUCATION ???????-???????????? ? ????????? ??????? ??????????? ?????????????? ??????????? ??????? ? ????????????? ???????? ?????? ??????

    Directory of Open Access Journals (Sweden)

    ?.?. ?????????

    2010-09-01

    Full Text Available In the article the problem of providing of document flow effective organization in the informative systems of industry of education is considered. Pre-conditions of the system creation are determined. The automated database “CIPPE students” http://www.students.edu-ua.net which provides processes automation of educational work document flow in the Central Institute of Post-graduate Pedagogical Education of APS of Ukraine is described .? ?????? ?????????? ???????? ???????????? ?????????? ??????????? ?????????????? ? ????????????? ???????? ?????? ??????, ????????? ???? ?????? ?????????????? ???? ????? „??????? ?????”. ????????? ?????????? ????????? ???????. ???????? ?????????? ?????? ? ????? ?????, ??? ?????????? ????????????? ???????? ??????????? ?????????? ?????? ? ???????????? ????????? ?????????????? ???????????? ?????? ??? ???????.

  13. Assessing winter storm flow generation by means of permeability of the lithology and dominating runoff production processes

    OpenAIRE

    Hellebrand, H.; Hoffmann, L.; J. Juilleret; Pfister, L.

    2007-01-01

    In this study two approaches are used to predict winter storm flow coefficients in meso-scale basins (10 km² to 1000 km²) with a view to regionalization. The winter storm flow coefficient corresponds to the ratio between direct discharge and rainfall. It is basin specific and supposed to give an integrated response to rainfall. The two approaches, which used the permeability of the substratum and dominating runoff generation processes as basin attributes are compared. The study area is the Rh...

  14. Measurement of void fraction in flow boiling of ZnO–water nanofluids using image processing technique

    International Nuclear Information System (INIS)

    Highlights: • Void fraction during flow boiling of nanofluids measured using optical techniques. • Bubble behavior of nanofluids was investigated and compared with water. • Nanofluids showed lower void fraction as compared to water. • Void fraction decreases with increasing nanoparticle concentration and flow rate. • Void fraction increases with heat flux and axial location of heated length. - Abstract: In recent years, nanofluids have been an active area of research in many engineering applications, especially for nuclear reactor safety systems due to their enhanced thermal properties as a coolant. In this study, experiments were performed in subcooled flow boiling of water and ZnO–water nanofluids with different nanoparticle concentrations (0.001–0.01 vol.%) in horizontal annulus at heat fluxes varying from 100 to 550 kW/m2 and flow rates from 0.1 to 0.175 lps at 1 bar inlet pressure and constant subcooling of 20 °C to determine the void fraction by image processing technique. Parametric effects of nanoparticle volume fraction, heat flux, flow rate and axial location of heater rod on void fraction were studied. Bubble images during flow boiling were captured with high speed visualization and analyzed by National Instruments IMAQ Vision Builder 6.1 image processing software. Results show that void fraction decreases up to 86% with the use of nanofluid in place of water and it also decreases with increasing nanoparticle concentration and flow rate, whereas increase in heat flux and axial location of heater rod have opposite effect

  15. Measurement of void fraction in flow boiling of ZnO–water nanofluids using image processing technique

    Energy Technology Data Exchange (ETDEWEB)

    Rana, K.B., E-mail: kunj.216@gmail.com [Department of Mechanical Engineering, Malaviya National Institute of Technology, Jaipur (India); Agrawal, G.D.; Mathur, J. [Department of Mechanical Engineering, Malaviya National Institute of Technology, Jaipur (India); Puli, U. [Faculty of Mechanical Engineering, Department of Technical Education, Government of Andhra Pradesh, Hyderabad (India)

    2014-04-01

    Highlights: • Void fraction during flow boiling of nanofluids measured using optical techniques. • Bubble behavior of nanofluids was investigated and compared with water. • Nanofluids showed lower void fraction as compared to water. • Void fraction decreases with increasing nanoparticle concentration and flow rate. • Void fraction increases with heat flux and axial location of heated length. - Abstract: In recent years, nanofluids have been an active area of research in many engineering applications, especially for nuclear reactor safety systems due to their enhanced thermal properties as a coolant. In this study, experiments were performed in subcooled flow boiling of water and ZnO–water nanofluids with different nanoparticle concentrations (0.001–0.01 vol.%) in horizontal annulus at heat fluxes varying from 100 to 550 kW/m{sup 2} and flow rates from 0.1 to 0.175 lps at 1 bar inlet pressure and constant subcooling of 20 °C to determine the void fraction by image processing technique. Parametric effects of nanoparticle volume fraction, heat flux, flow rate and axial location of heater rod on void fraction were studied. Bubble images during flow boiling were captured with high speed visualization and analyzed by National Instruments IMAQ Vision Builder 6.1 image processing software. Results show that void fraction decreases up to 86% with the use of nanofluid in place of water and it also decreases with increasing nanoparticle concentration and flow rate, whereas increase in heat flux and axial location of heater rod have opposite effect.

  16. Realization of an Optimal Schedule for the Two-machine Flow-Shop with Interval Job Processing Times

    OpenAIRE

    Leshchenko, Natalja; Sotskov, Yuri

    2007-01-01

    Non-preemptive two-machine flow-shop scheduling problem with uncertain processing times of n jobs is studied. In an uncertain version of a scheduling problem, there may not exist a unique schedule that remains optimal for all possible realizations of the job processing times. We find necessary and sufficient conditions (Theorem 1) when there exists a dominant permutation that is optimal for all possible realizations of the job processing times. Our computational studies show the p...

  17. 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.

  18. 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,

  19. Flow

    OpenAIRE

    Pamela Markus

    2007-01-01

    What is student engagement? How do teachers engage their students? As a way to address these questions, I used collage as an arts-informed method for exploring the subject of student engagement. The collages are displayed and I describe the process of producing this work.

  20. Sediment mass-flow processes on a depositional lobe, outer Mississippi Fan

    Science.gov (United States)

    Schwab, W.C.; Lee, H.J.; Twichell, D.C.; Locat, J.; Nelson, C.H.; McArthur, W.G.; Kenyon, Neil H.

    1996-01-01

    SeaMARC 1A sidescan-sonar imagery and cores from the distal reaches of a depositional lobe on the Mississippi Fan show that channelized mass flow was the dominant mechanism for transport of silt and sand during the formation of this part of the fan. Sediments in these flows were rapidly deposited once outside of their confining channels. The mass flows most likely originated from slope failure at the head of the Mississippi Canyon or on the outer continental shelf and flowed approximately 500 km to the distal reaches of the fan, with debris flow being the dominant flow type.

  1. Vogan diagrams of affine twisted Lie superalgebras

    OpenAIRE

    Ransingh, Biswajit

    2013-01-01

    A Vogan diagram is a Dynkin diagram with a Cartan involution of twisted affine superlagebras based on maximally compact Cartan subalgebras. This article construct the Vogan diagrams of twisted affine superalgebras. It is a part of completion of classification of vogan diagrams to superalgebras cases.

  2. Cut Diagrams for High Energy Scatterings

    OpenAIRE

    Feng, Y. J.; Hamidi-Ravari, O.; Lam, C. S.

    1996-01-01

    A new approach is introduced to study QCD amplitudes at high energy and comparatively small momentum transfer. Novel cut diagrams, representing resummation of Feynman diagrams, are used to simplify calculation and to avoid delicate cancellations encountered in the usual approach. Explicit calculation to the 6th order is carried out to demonstrate the advantage of cut diagrams over Feynman diagrams.

  3. Automatically Assessing Graph-Based Diagrams

    Science.gov (United States)

    Thomas, Pete; Smith, Neil; Waugh, Kevin

    2008-01-01

    To date there has been very little work on the machine understanding of imprecise diagrams, such as diagrams drawn by students in response to assessment questions. Imprecise diagrams exhibit faults such as missing, extraneous and incorrectly formed elements. The semantics of imprecise diagrams are difficult to determine. While there have been…

  4. Solid gas reaction phase diagram under high gas pressure

    International Nuclear Information System (INIS)

    This paper reports that to evaluate which are the stable phases under high gas pressure conditions, a solid-gas reaction phase diagram under high gas pressure (HIP phase diagram) has been proposed by the author. The variables of the diagram are temperature, reactant gas partial pressure and total gas pressure. Up to the present time the diagrams have been constructed using isobaric conditions. In this work, the stable phases for a real HIP process were evaluated assuming an isochoric condition. To understand the effect of the total gas pressure on stability is of primary importance. Two possibilities were considered and evaluated, those are: the total gas pressure acts as an independent variable, or it only affects the fugacity values. The results of this work indicate that the total gas pressure acts as an independent variable, and in turn also affects the fugacity values

  5. Flow of Information during an Evolutionary Process: The Case of Influenza A Viruses

    Directory of Open Access Journals (Sweden)

    Marco V. José

    2013-07-01

    Full Text Available The hypothesis that Mutual Information (MI dendrograms of influenza A viruses reflect informational groups generated during viral evolutionary processes is put forward. Phylogenetic reconstructions are used for guidance and validation of MI dendrograms. It is found that MI profiles display an oscillatory behavior for each of the eight RNA segments of influenza A. It is shown that dendrograms of MI values of geographically and historically different segments coming from strains of RNA virus influenza A turned out to be unexpectedly similar to the clusters, but not with the topology of the phylogenetic trees. No matter how diverse the RNA sequences are, MI dendrograms crisply discern actual viral subtypes together with gain and/or losses of information that occur during viral evolution. The amount of information during a century of evolution of RNA segments of influenza A is measured in terms of bits of information for both human and avian strains. Overall the amount of information of segments of pandemic strains oscillates during viral evolution. To our knowledge this is the first description of clades of information of the viral subtypes and the estimation of the flow content of information, measured in bits, during an evolutionary process of a virus.

  6. Spatial Density Voronoi Diagram and Construction

    Directory of Open Access Journals (Sweden)

    Ye Zhao

    2012-08-01

    Full Text Available To fill a theory gap of Voronoi diagrams that there have been no reports of extended diagrams in spatial density so far. A new concept of spatial density Voronoi diagram was proposed. An important property was presented and proven. And a construction algorithm was presented. Spatial density can be used to indicate factors related to density such as conveyance and the traffic conditions. Some properties of spatial density Voronoi diagram were also introduced. In accordance with discrete construction method, achieved the construction of spatial density Voronoi diagram. Spatial density Voronoi diagram is a developed Voronoi diagram, and planar ordinary Voronoi diagram can be regarded as its special cases. It both perfected the theory about Voronoi diagrams, and extended the range of applications of Voronoi diagrams.

  7. 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.

  8. 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.

  9. 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.)

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

    OpenAIRE

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

    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...

  11. The formation of shear and density layers in stably stratified turbulent flows: linear processes

    Science.gov (United States)

    Galmiche, M.; Hunt, J. C. R.

    2002-03-01

    The initial evolution of the momentum and buoyancy fluxes in a freely decaying, stably stratified homogeneous turbulent flow with r.m.s. velocity u[prime prime or minute]0 and integral lengthscale l0 is calculated using a weakly inhomogeneous and unsteady form of the rapid distortion theory (RDT) in order to study the growth of small temporal and spatial perturbations in the large-scale mean stratification N(z, t) and mean velocity profile u(z, t) (here N is the local Brunt Väisälä frequency and u is the local velocity of the horizontal mean flow) when the ratio of buoyancy forces to inertial forces is large, i.e. Nl0/u[prime prime or minute]0[dbl greater-than sign]1. The lengthscale L of the perturbations in the mean profiles of stratification and shear is assumed to be large compared to l0 and the presence of a uniform background mean shear can be taken into account in the model provided that the inertial shear forces are still weaker than the buoyancy forces, i.e. when the Richardson number Ri = (N/[partial partial differential]zu)2[dbl greater-than sign]1 at each height.When a mean shear perturbation is introduced initially with no uniform background mean shear and uniform stratification, the analysis shows that the perturbations in the mean flow profile grow on a timescale of order N-1. When the mean density profile is perturbed initially in the absence of a background mean shear, layers with significant density gradient fluctuations grow on a timescale of order N[minus sign]10 (where N0 is the order of magnitude of the initial Brunt Väisälä frequency) without any associated mean velocity gradients in the layers. These results are in good agreement with the direct numerical simulations performed by Galmiche et al. (2002) and are consistent with the earlier physically based conjectures made by Phillips (1972) and Posmentier (1977). The model also shows that when there is a background mean shear in combination with perturbations in the mean stratification, negative shear stresses develop which cause the mean velocity gradient to grow in the density layers. The linear analysis for short times indicates that the scale on which the mean perturbations grow fastest is of order u[prime prime or minute]0/N0, which is consistent with the experiments of Park et al. (1994).We conclude that linear mechanisms are widely involved in the formation of shear and density layers in stratified flows as is observed in some laboratory experiments and geophysical flows, but note that the layers are also significantly influenced by nonlinear and dissipative processes at large times.

  12. 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°.

  13. 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.

  14. 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.

    2015-02-01

    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. 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 water, 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 Primavera caldera and is found predominantly in wells in the upper Atemajac Valley. Hydrothermal water is characterized by high salinity, temperature, Cl, Na, 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 practices. Mixed groundwaters between cold and hydrothermal components are predominantly found in the lower Atemajac Valley. Tritium method elucidated that practically all of the sampled groundwater contains at least a small fraction of modern water. The multivariate mixing model M3 indicates that the proportion of hydrothermal fluids in sampled well water is between 13 (local groundwater) and 87% (hydrothermal water), and the proportion of polluted water in wells ranges from 0 to 63%. This study may help local water authorities to identify and quantify groundwater contamination and act accordingly.

  15. Industrial application of ultrasound based in-line rheometry: From stationary to pulsating pipe flow of chocolate suspension in precrystallization process

    Science.gov (United States)

    Ouriev, Boris; Windhab, Erich; Braun, Peter; Birkhofer, Beat

    2004-10-01

    In-line visualization and on-line characterization of nontransparent fluids becomes an important subject for process development in food and nonfood industries. In our work, a noninvasive Doppler ultrasound-based technique is introduced. Such a technique is applied for investigation of nonstationary flow in the chocolate precrystallization process. Unstable flow conditions were induced by abrupt flow interruption and were followed up by strong flow pulsations in the piping system. While relying on available process information, such as absolute pressures and temperatures, no analyses of flow conditions or characterization of suspension properties could possibly be done. It is obvious that chocolate flow properties are sensitive to flow boundary conditions. Therefore, it becomes essential to perform reliable structure state monitoring and particularly in application to nonstationary flow processes. Such flow instabilities in chocolate processing can often lead to failed product quality with interruption of the mainstream production. As will be discussed, a combination of flow velocity profiles, on-line fit into flow profiles, and pressure difference measurement are sufficient for reliable analyses of fluid properties and flow boundary conditions as well as monitoring of the flow state. Analyses of the flow state and flow properties of chocolate suspension are based on on-line measurement of one-dimensional velocity profiles across the flow channel and their on-line characterization with the power-law model. Conclusions about flow boundary conditions were drawn from a calculated velocity standard mean deviation, the parameters of power-law fit into velocity profiles, and volumetric flow rate information.

  16. Simulation of bacteria transport processes in a river with Flow3D

    Science.gov (United States)

    Schwarzwälder, Kordula; Bui, Minh Duc; Rutschmann, Peter

    2014-05-01

    Water quality aspects are getting more and more important due to the European water Framework directive (WFD). One problem related to this topic is the inflow of untreated wastewater due to combined sewer overflows into a river. The wastewater mixture contains even bacteria like E. coli and Enterococci which are markers for water quality. In our work we investigated the transport of these bacteria in river Isar by using a large-scale flume in the outside area of our lab (Oskar von Miller Institute). Therefor we could collect basic data and knowledge about the processes which occur during bacteria sedimentation and remobilisation. In our flume we could use the real grain with the exact size distribution curve as in the river Isar which we want to simulate and we had the chance to nurture a biofilm which is realistic for the analysed situation. This biofilm plays an important role in the remobilisation processes, because the bacteria are hindered to be washed out back into the bulk phase as fast and in such an amount as this would happen without biofilm. The results of our experiments are now used for a module in the 3D software Flow3D to simulate the effects of a point source inlet of raw wastewater on the water quality. Therefor we have to implement the bacteria not as a problem of concentration with advection and diffusion but as single particles which can be inactivated during the process of settling and need to be hindered from remobilisation by the biofilm. This biofilm has special characteristic, it is slippery and has a special thickness which influences the chance of bacteria being removed. To achieve realistic results we have to include the biofilm with more than a probabilistic-tool to make sure that our module is transferable. The module should be as flexible as possible to be improved step by step with increasing quality of dataset.

  17. 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 omic recovery is a dominant softening mechanism at higher strain rates (?1.0 s?1)

  18. Phase diagram and kinetics of inhomogeneous square lattice brittle fracture

    Science.gov (United States)

    Lebovka, N. I.; Mank, V. V.

    1992-02-01

    The process of brittle fracture of an inhomogeneous 2D square lattice is studied in the framework of a deterministic model. The phase diagram defining the conditions for different modes of fracture is obtained. The kinetics of the fracture processes is shown to be described by an Avrami-type relation. An equation for the durability of inhomogeneous system is proposed.

  19. Void fraction measurement in two-phase flow processes via symbolic dynamic filtering of ultrasonic signals

    International Nuclear Information System (INIS)

    This communication introduces a non-intrusive method for void fraction measurement and identification of two-phase flow regimes, based on ultrasonic sensing. The underlying algorithm is built upon the recently reported theory of a statistical pattern recognition method called symbolic dynamic filtering (SDF). The results of experimental validation, generated on a laboratory test apparatus, show a one-to-one correspondence between the flow measure derived from SDF and the void fraction measured by a conductivity probe. A sharp change in the slope of flow measure is found to be in agreement with a transition from fully bubbly flow to cap-bubbly flow. (rapid communication)

  20. Pyroclastic flow erosion and bulking processes: comparing field-based vs. modeling results at Tungurahua volcano, Ecuador

    Science.gov (United States)

    Bernard, Julien; Kelfoun, Karim; Le Pennec, Jean-Luc; Vallejo Vargas, Silvia

    2014-09-01

    Pyroclastic density currents (PDCs) are high-temperature and high-velocity mixtures that threaten populations in the vicinity of many active volcanoes. Deciphering the cause of their remarkable mobility is essential for volcanic hazard analysis, but remains difficult because of the complex processes occurring within the flows. Here, we investigate the effect of bulking on dense PDC mobility by means of a double approach. First, we estimate the amount of material incorporated into scoria flows emplaced during the August 2006 eruption of Tungurahua volcano, Ecuador. For this, we carry out a detailed analysis of 3D-corrected digital images of well-exposed scoria flow deposits. Componentry analysis indicates that PDC bulking occurs principally on the steep (>25°) upper slope of the volcano, and the deposits typically comprise 40-50 wt% of non-juvenile (i.e., accessory and accidental) material. Secondly, we develop a simple stress-related grain-by-grain equation of erosion combined with two simple depth-averaged geophysical mass-flow models that compare the bulking mechanism to a non-fluidized and a fluidized flow. Two behaviors based on Coulomb and plastic rheologies are used to reproduce, on a first order basis, the 2006 Tungurahua PDCs. Cross-check comparisons between these modeled cases and the erosion pattern inferred from field-based data allow us to evaluate the accuracy of our modeling assumptions. Regardless of the rheological regime, the PDC-induced erosion pattern of the 2006 Tungurahua eruption can only be reproduced by fluctuations of the flow's basal shear stress during emplacement. Such variations are controlled by flow thinning-thickening processes, notably through the formation of a thick non-erosive flow body that pushes a thin frictional erosive front during PDC emplacement. The input volume of juvenile material, as well as the thickness of the erodible layer available prior to the eruption, are additional key parameters. Our work highlights complexities in PDC erosion and bulking processes that deserve further study. In terms of hazard assessment, our findings reveal that incorporation and bulking translate into increased flow mobility, i.e., the augmented flow mass enhances both flow velocity and runout distance (up to 20 %). These outcomes should be considered closely for hazard analysis at many other andesitic volcanoes worldwide where similar PDC events are common.