WorldWideScience
 
 
1

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

Energy Technology Data Exchange (ETDEWEB)

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.

KLEM, M.J.

2000-05-11

2

Process logic flow diagram write up for the Advanced Recovery and Integrated Extraction System (ARIES) facility  

Energy Technology Data Exchange (ETDEWEB)

The Department of Energy Office of Fissile Materials Disposition (DOE-MD) is planning a facility to disassemble pits and convert the plutonium in the pits into a form suitable for international inspection. The facility, called the Advanced Recovery and Integrated Extraction System (ARIES) Facility, must handle much of the 38.2 metric tons of plutonium declared excess to national security needs in ten years of operation. A process logic flow diagram for the ARIES Facility is presented here. This flow diagram is based on and supported by a library of fact sheets on topics that impact the design of the facility. Developing the flow diagram raised issues that significantly impact the design of the facility. These issues are discussed later in this document, and for some issues, discussed in greater detail in the appropriate fact sheets. The flow diagram is designed to show requirements that dictate the need for space and/or equipment. In physically designing the facility, the same space or equipment may be used to meet several requirements. The flow diagram merely shows the activities that need to occur to meet requirements for the facility. The flow diagram is not associated with any DOE site. The requirements shown on the flow diagram may be met by an existing facilities at a given site. The flow diagram and this write up do not contain a great deal of detail on how each step in the diagram is performed. At this stage of design, the flow diagram merely identifies the need for the activity. Examples for some of the activities are given in the appropriate fact sheet. How the steps are performed becomes more defined as the design of the facility progresses.

Zygmunt, S.J.

1997-05-01

3

Spent Nuclear Fuel (SNF) Project Multi Canister Overpack (MCO) Process Flow Diagram Mass Balance Calculations  

International Nuclear Information System (INIS)

The purpose of this calculation document is to develop the bases for the material balances of the Multi-Canister Overpack (MCO) Level 1 Process Flow Diagram (PFD). The attached mass balances support revision two of the PFD for the MCO and provide future reference

2000-01-01

4

Spent Nuclear Fuel (SNF) Project Multi Canister Overpack (MCO) Process Flow Diagram Mass Balance Calculations  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this calculation document is to develop the bases for the material balances of the Multi-Canister Overpack (MCO) Level 1 Process Flow Diagram (PFD). The attached mass balances support revision two of the PFD for the MCO and provide future reference.

KLEM, M.J.

2000-09-08

5

Diagrams for laser materials processing  

Science.gov (United States)

An analytical heat flow model is used to identify dimensionless parameter groups which determine the temperature field produced in a material by a scanning laser beam. The groups are used to plot experimental data for metallic alloys on a processing diagram for a range of continuous CO2 laser treatments. Practical operating regions for each type of treatment are thus identified, which coincide with those predicted using the heat flow model. The model is extended in order to construct more detailed diagrams for transformation hardening, surface melting and keyhole welding, which quantify the depth of treatment. By using realistic estimates of certain poorly-known process variables, good agreement is observed between measured and predicted data. Methods for optimizing processing parameters with respect to various criteria are presented for transformation hardening. The diagrams, which are constructed on a personal computer, are a useful tool for summarizing current data, optimizing practical processing parameters, and assessing the potential of novel laser treatments on new materials.

Ion, J. C.; Shercliff, H. R.; Ashby, M. F.

1992-07-01

6

Semantics of Data Flow Diagrams.  

Science.gov (United States)

Ways in which semantics can be attached to data flow diagrams are described. A method for transforming a Data Flow Diagram (DFD) into a petri net which specificies the synchronization aspects of a DFD is presented. A sketch of how a DFD may be transformed...

P. D. Bruza T. P. Vanderweide

1989-01-01

7

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

CERN Multimedia

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...

Loewe, Laurence; Hillston, Jane

2009-01-01

8

Formalization of the Data Flow Diagram Rules for Consistency Check  

Directory of Open Access Journals (Sweden)

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.

Rosziati Ibrahim; Siow Yen Yen

2010-01-01

9

Formalization of the data flow diagram rules for consistency check  

CERN Document Server

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 its rules for drawing and defining the diagrams. We then formalize these rules and develop the tool based on the formalized rules. The formalized rules for consistency check between the diagrams are used in developing 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.

Ibrahim, Rosziati; 10.5121/ijsea.2010.1406

2010-01-01

10

Architecture flow diagrams under teamwork reg sign  

Energy Technology Data Exchange (ETDEWEB)

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

Nicinski, T.

1992-02-01

11

Automated Methodologies for the Design of Flow Diagrams for Development and Maintenance Activities  

Science.gov (United States)

The Software Requirements Specification (SRS) of the organization is a text document prepared by strategic management incorporating the requirements of the organization. These requirements of ongoing business/ project development process involve the software tools, the hardware devices, the manual procedures, the application programs and the communication commands. These components are appropriately ordered for achieving the mission of the concerned process both in the project development and the ongoing business processes, in different flow diagrams viz. activity chart, workflow diagram, activity diagram, component diagram and deployment diagram. This paper proposes two generic, automatic methodologies for the design of various flow diagrams of (i) project development activities, (ii) ongoing business process. The methodologies also resolve the ensuing deadlocks in the flow diagrams and determine the critical paths for the activity chart. Though both methodologies are independent, each complements other in authenticating its correctness and completeness.

Shivanand M., Handigund; Shweta, Bhat

12

A Formal Model for Data Flow Diagram Rules  

Directory of Open Access Journals (Sweden)

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

Rosziati Ibrahim; Siow Yen Yen

2011-01-01

13

Architecture flow diagrams under teamwork{reg_sign}  

Energy Technology Data Exchange (ETDEWEB)

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

Nicinski, T.

1992-02-01

14

Introducing the Circular Flow Diagram to Business Students  

Science.gov (United States)

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

Daraban, Bogdan

2010-01-01

15

Material flow of production process  

Directory of Open Access Journals (Sweden)

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.

Hanzelová Marcela

2001-01-01

16

Some bifurcation diagrams for Taylor vortex flows  

International Nuclear Information System (INIS)

The numerical continuation and bifurcation methods of Keller [H. B. Keller, in Applications of Bifurcation Theory (Academic, New York, 1977), pp. 359--384] are used to study the variation of some branches of axisymmetric Taylor vortex flow as the wavelength in the axial direction changes. Closed ''loops'' of solutions and secondary bifurcations are determined. Variations with respect to Reynolds number show the same phenomena. The results presented here show that Taylor vortices with periodic boundary conditions exist in a wider range of wavelengths, lambda, than observed in the Burkhalter/Koschmieder experiments [Phys. Fluids 17, 1929 (1974)]. They also show that there is possibly a lambda subinterval within the neutral curve of Couette flow such that there are no Taylor vortex flows with smallest period in this interval.

1985-01-01

17

Phase Diagram Information for Processing of Superconductors.  

Science.gov (United States)

Composition of various superconducting compounds with potentially high critical temperature (greater than 20K) is discussed. Phase diagrams of Nb--Al--Ge, Nb--Sn--Cu, and Nb--Ge--Cu are given. (ERA citation 02:054781)

D. Dew-Hughes

1977-01-01

18

Derivation of a Fundamental Diagram for Urban Traffic Flow  

CERN Document Server

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

Helbing, Dirk

2008-01-01

19

The Exergy of Lift and Aircraft Exergy Flow Diagrams  

Directory of Open Access Journals (Sweden)

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

David M. Paulus, Jr.; Richard A. Gaggioli

2003-01-01

20

An Operational Semantics of Firing Rules for Structured Analysis Style Data Flow Diagrams  

UK PubMed Central (United Kingdom)

Using operational semantic techniques, an extended variant of structured analysisstyle data flow diagrams is given a formal semantics. This semantics allows one todescribe both how information is processed and the dynamic behavior of the system.The ability to describe dynamic behavior is an extension to the traditional notion of dataflow diagrams. This semantics can serve as a target for giving meaning to specificationlanguages that use a graphical notation similar to data flow diagrams.1 IntroductionAn approach to the development of software systems which has enjoyed wide-spread use inthe software engineering community is Structured Analysis (SA) [DeM78] [GS78] [WM85][You89]. Within SA one specifies a data model using an Entity-Relationship Diagram (ERD)and a data dictionary, and the process by a Data Flow Diagram (DFD) [Fra93]. BecauseDFDs are widely-used [BB93], many tools support their development. There are at leastthree attributes of DFDs that are appealing to softwa...

Gary T. Leavens; Tim Wahls; Albert L. Baker; Kari Lyle

 
 
 
 
21

Flow phase diagrams for concentration-coupled shear banding.  

Science.gov (United States)

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

Fielding, S M; Olmsted, P D

2003-05-01

22

Flow phase diagrams for concentration-coupled shear banding.  

UK PubMed Central (United Kingdom)

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

Fielding SM; Olmsted PD

2003-05-01

23

Phase diagram of single vesicle dynamical states in shear flow.  

UK PubMed Central (United Kingdom)

We report the first experimental phase diagram of vesicle dynamical states in a shear flow presented in a space of two dimensionless parameters suggested recently by V. Lebedev et al. To reduce errors in the control parameters, 3D geometrical reconstruction and determination of the viscosity contrast of a vesicle in situ in a plane Couette flow device prior to the experiment are developed. Our results are in accord with the theory predicting three distinctly separating regions of vesicle dynamical states in the plane of just two self-similar parameters.

Deschamps J; Kantsler V; Steinberg V

2009-03-01

24

Phase diagrams of the Katz-Lebowitz-Spohn process on lattices with a junction.  

UK PubMed Central (United Kingdom)

This paper studies the Katz-Lebowitz-Spohn (KLS) process on lattices with a junction, where particles move on parallel lattice branches that combine into a single lattice at the junction. It is shown that 11 kinds of phase diagrams could be observed, depending on the two parameters ? and ? in the KLS process. We have investigated the phase diagrams as well as bulk density analytically based on flow rate conservation and the extremal current principle. Extensive Monte Carlo computer simulations are performed, and it is found that they are in excellent agreement with theoretical prediction.

Tian B; Jiang R; Ding ZJ; Hu MB; Wu QS

2013-06-01

25

Phase diagrams of the Katz-Lebowitz-Spohn process on lattices with a junction.  

Science.gov (United States)

This paper studies the Katz-Lebowitz-Spohn (KLS) process on lattices with a junction, where particles move on parallel lattice branches that combine into a single lattice at the junction. It is shown that 11 kinds of phase diagrams could be observed, depending on the two parameters ? and ? in the KLS process. We have investigated the phase diagrams as well as bulk density analytically based on flow rate conservation and the extremal current principle. Extensive Monte Carlo computer simulations are performed, and it is found that they are in excellent agreement with theoretical prediction. PMID:23848644

Tian, Bo; Jiang, Rui; Ding, Zhong-Jun; Hu, Mao-Bin; Wu, Qing-Song

2013-06-18

26

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

Directory of Open Access Journals (Sweden)

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

James PH Coleman

2013-01-01

27

Improving The Decisional Process By Using UML Diagrams  

Directory of Open Access Journals (Sweden)

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.

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

2012-01-01

28

Design of processes with reactive distillation line diagrams  

Energy Technology Data Exchange (ETDEWEB)

On the basis of the transformation of concentration coordinates, the concept of reactive distillation lines is developed. It is applied to study the feasibility of a reactive distillation with an equilibrium reaction on all trays of a distillation column. The singular points in the distillation line diagrams are characterized in terms of nodes and saddles. Depending on the characterization of the reactive distillation line diagrams, it can be decided whether a column with two feed stages is required. On the basis of the reaction space concept, a procedure for identification of reactive distillation processes is developed, in which the reactive distillation column has to be divided into reactive and nonreactive sections. This can be necessary to overcome the limitations in separation which result from the chemical equilibrium. The concentration profile of this combined reactive/nonreactive distillation column is estimated using combined reactive/nonreactive distillation lines.

Bessling, B. [BASF Ludwigshafen (Germany). Engineering Research and Development; Schembecker, G.; Simmrock, K.H. [Univ. of Dortmund (Germany). Dept. of Chemical Engineering

1997-08-01

29

Merging Object and Process Diagrams for Business Information Modeling  

CERN Multimedia

While developing an information system for the University of Bern, we were faced with two major issues: managing software changes and adapting Business Information Models. Software techniques well-suited to software development teams exist, yet the models obtained are often too complex for the business user. We will first highlight the conceptual problems encountered while designing the Business Information Model. We will then propose merging class diagrams and business process modeling to achieve a necessary transparency. We will finally present a modeling tool we developed which, using pilot case studies, helps to show some of the advantages of a dual model approach.

Chénais, Patrick

2008-01-01

30

Rapid granular flows on a rough incline: phase diagram, gas transition, and effects of air drag  

CERN Multimedia

We report experiments on the overall phase diagram of granular flows on an incline with emphasis on high inclination angles where the mean layer velocity approaches the terminal velocity of a single particle free falling in air. The granular flow was characterized by measurements of the surface velocity, the average layer height, and the mean density of the layer as functions of the hopper opening, the plane inclination angle and the downstream distance x of the flow. At high inclination angles the flow does not reach an x-invariant steady state over the length of the inclined plane. For low volume flow rates, a transition was detected between dense and very dilute (gas) flow regimes. We show using a vacuum flow channel that air did not qualitatively change the phase diagram and did not quantitatively modify mean flow velocities of the granular layer except for small changes in the very dilute gas-like phase.

Borzsonyi, T; Borzsonyi, Tamas; Ecke, Robert E.

2006-01-01

31

Trajectories of renormalization group flows on the phase diagram of N=2 superconformal field theories  

International Nuclear Information System (INIS)

Trajectories of renormalization group flows of N=2 super Landau-Ginzburg field theories are mapped out on the phase diagram N=2 superconformal field theories (SCFTs). It is shown that coupling constants flow on one and the same bifurcation set due to the non-renormalization theorem and the scaling properties of the bifurcation sets. (author). 17 refs, 2 figs.

1989-01-01

32

Application of quaternary phase diagrams to compound semiconductor processing.  

Science.gov (United States)

Isobaric, isothermal phase diagrams are a molar representation of condensed phases in equilibrium with each other at a fixed temperature, pressure, and composition. Since three or four elements are usually involved at a fabricated interface in a semicondu...

R. Sinclair

1994-01-01

33

XML transformation flow processing  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The XSLT language is both complex to use in simple cases (like tag renaming or element hiding) and restricted in complex ones (requiring the processing of multiple stylesheets with complex information flows). We propose a framework improving on XSLT. It provides simple-to-use and easy-to-analyze mac...

Euzenat, Jérôme; Tardif, Laurent

34

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

CERN Multimedia

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

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

2008-01-01

35

Modeling and Simulating Computer Networks Using Formalized Data Flow Diagrams  

UK PubMed Central (United Kingdom)

functions are simplyparameterized assertions. All the abstract functions that appear in the firing rules will beexplained and defined later in this section. Also note that "special symbols" in assertions arewritten with an ASCII representation to facilitate parsing and type checking. For example, theuniversal quantifier is written nforall and not 8, and the "and" operator is written /n, and not.The first firing rule listed sends a routing table to each neighbor when a token is present on theinflow from Timer.+T /" +ND:---= ND' = ND /""forall (IDType n) [n "elem neighbors(ND) =?OutPacket'n = (i,n,(i,rt(ND)))]The enabling condition requires that a signal be present on the inflow T from Timer and theinflow ND. In fact, every firing rule will contain +ND as part of the enabling condition, asthere is always exactly one token on flow ND. The precondition is blank and assumed to be true,indicating that there are no other restrictions on the inflow value, other than those pro...

Michael D. Haverdink; Albert L. Baker; Armin Mikler

36

Systematic analysis of biochemical processes in cells by applying graphical diagrams  

Energy Technology Data Exchange (ETDEWEB)

A method for systematically analyzing biochemical reactions in a cell was proposed. One of the characteristic features of biochemical reactions in a cell is that many components are participating and that quite many reactions are taking place. Also bio-separation processes are observed. We applied material-utilization diagrams to systematically grasp such a biochemical process. We used two diagrams. In the first diagram, the change in concentration for each component was presented, whereas in the second diagram, the deviation of each biochemical reaction from the equilibrium condition was displayed. Those diagrams suggested the possibility to improve the biochemical process, since they revealed the exergy losses caused by changes in concentration or biochemical reactions. (author)

Ishida, M.; Okuno, K. [Tokyo Institute of Technology, Yokohama (Japan). Chemical Resources Laboratory

2002-12-01

37

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

Science.gov (United States)

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.

Li, Hongzhou; Wu, Xin; Li, Guangyao

2013-08-01

38

An Operational Semantics of Firing Rules for Structured Analysis Style Data Flow Diagrams  

UK PubMed Central (United Kingdom)

Using operational semantic techniques, we give a precise formal description of thefiring rules of data flow diagrams. This semantics can serve as a foundation for theformalization of structured analysis specifications.1 IntroductionFormal methods or informal methods? Members of the software engineering communityhave been compelled to line up on one side of the issue or the other. Either you are a "piein-the-sky" researcher or just trying to meet the next delivery deadline. In this paper wesuggest that using a more formal approach to a widely used informal specification techniquecreates a practical middle ground for software developers.The informal technique we address is Structured Analysis (SA). SA is an approach tothe development of software systems which has received wide-spread use in the softwareengineering community for over 15 years [DeM78] [WM85] [You89]. Within SA, the specificationphase of software development is based on Data Flow Diagrams (DFDs). MostComputer...

Gary T. Leavens; Tim Wahls; Albert L. Baker; Kari Lyle

39

Flow diagram of the metal-insulator transition in two dimensions  

CERN Document Server

We have experimentally verified that the metal-insulator transition in two-dimensional electron liquid is caused by the interplay of the disorder and interactions. In particular, we have reconstructed the resistance-interaction flow diagram which clearly manifests the existence of a quantum critical point. On the metallic side of the transition, the resistance is found to quantitatively follow the universal theoretical dependence.

Anissimova, S; Punnoose, A; Finkelstein, A M; Klapwijk, T M

2006-01-01

40

Mechanical anisotropy and construction of flow stress diagrams during the annealing of Zr-1% Sn alloy  

International Nuclear Information System (INIS)

In the present study the annealing behavior of 60% reduced and stress relieved Zircaloy-4 nuclear fuel cladding tube is studied over a temperature range of 300-1000 deg. C and an annealing time range of 103 to 105 s. The annealing effects were monitored using Knoop microhardness measurements and flow stress diagrams were developed to study the mechanical anisotropy evolution in the tubing. The determined values of the mechanical anisotropy ratios show that the tubing undergoes a significant mechanical anisotropy evolution during annealing.

2008-02-15

 
 
 
 
41

The phase diagram of quantum gravity from diffeomorphism-invariant RG-flows  

CERN Document Server

We evaluate the phase diagram of quantum gravity within a fully diffeomorphism-invariant renormalisation group approach. The construction is based on the geometrical or Vilkovisky-DeWitt effective action. We also resolve the difference between the fluctuation metric and the background metric. This allows for fully background-independent flows in gravity. The results provide further evidence for the ultraviolet fixed point scenario in quantum gravity with quantitative changes for the fixed point physics. We also find a stable infrared fixed point related to classical Einstein gravity. Implications and possible extensions are discussed.

Donkin, Ivan

2012-01-01

42

Methods for effective thermodynamic modelling using an example of a modular programming package for calculating heat-flow diagrams (thermal circuit diagrams). Methoden zur effektiven thermodynamischen Modellierung am Beispiel eines modularen Programmpaketes zur Waermeschaltbildberechnung (WSB)  

Energy Technology Data Exchange (ETDEWEB)

Presentation is made on the development of a modular method for the flexible calculation of heat-flow diagrams (thermal circuit diagrams) which do not require concrete control programs of the circuit. This systematics eliminates the time-consuming writing and modification of control algorithms for corrections or variations of the concrete appliance connection scheme. The following principles can be derived for the thermodynamic modelling of technical energy connection schemes of the appliance using means and methods of technical computing. The system model; the model calculation procedure; collection/maintenance of the model elements in catalogue form; effective/quality-assured development implementation of the solution methodology; implementation of the architecture principle; portability/compatibility of the solution (hardware-independent interfaces), computing methodology - user interfaces; process adaption to the CAE (computer-aided engineering) technique. (HWJ).

Buerkner, R.

1990-04-19

43

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

Science.gov (United States)

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

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

2013-09-01

44

FMEF Electrical single line diagram and panel schedule verification process  

Energy Technology Data Exchange (ETDEWEB)

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.

FONG, S.K.

1998-11-11

45

Development of energy, emission and water flow Sankey diagrams for the Province of Alberta through modeling  

Energy Technology Data Exchange (ETDEWEB)

The objective of this research is to develop a data intensive energy-environment and Alberta-specific energy planning and forecasting tool using the long range energy alternative planning systems model (LEAP). Sankey diagrams of energy and emission flow are developed in this model. The model presents a complete energy structure including major as well as minor energy users for the demand and supply sectors, which greatly helps to understand Alberta's whole energy distribution system. This developed model, along with the database including infrastructure data could be used by different departments when policy decisions or project assessments are made. The LEAP model also develops greenhouse gas (GHG) mitigation scenarios, which would be of assistance in future development and maintenance of Alberta's energy and environment modeling capability. It can also be applied as system training for energy and environment departments in these areas.

Kumar, Amit; Subramanyam, Veena; Kabir, Ruhul [Department of Mechanical Engineering, University of Alberta (Canada)

2011-04-15

46

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

Directory of Open Access Journals (Sweden)

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.

A. Pukos; M. Pezda; A. Guc

1995-01-01

47

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

Directory of Open Access Journals (Sweden)

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

Sevilay Karamustafao?lu

2011-01-01

48

Control structures for flow process  

Directory of Open Access Journals (Sweden)

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

Mircea Dul?u; Hora?iu Grif; Stelian Oltean; Rezi Attila

2011-01-01

49

Phase diagram structures in a periodic one-dimensional exclusion process.  

UK PubMed Central (United Kingdom)

This paper studies a periodic one-dimensional exclusion process composed of a driven part and a biased diffusive part in a mesoscopic limit. It is shown that, depending on the biased diffusion parameter ?, rich phase diagram structures appear in which diverse phases have been exhibited and the density profile in the diffusive part is qualitatively different. This is because the domain wall is behaving differently. Our analytical results are in good agreement with Monte Carlo simulations.

Jiang R; Wang YQ; Kolomeisky AB; Huang W; Hu MB; Wu QS

2013-01-01

50

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)

2013-01-01

51

Flow Logic for Process Calculi  

DEFF Research Database (Denmark)

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.

Nielson, Hanne Riis; Nielson, Flemming

2012-01-01

52

Mass divergences in annihilation processes. I. Origin and nature of divergences in cut vacuum polarization diagrams  

International Nuclear Information System (INIS)

The origin of mass divergences in internal loop momentum integrals of cut vacuum polarization diagrams is investigated. It is found that loop momentum configurations which can give rise to mass divergences are of a severely limited form and have a direct interpretation in terms of physically realizable processes. A power-counting procedure suitable for estimating the nature of mass divergences is developed, and it is found that in a large class of field theories, cross sections smeared over a small region of phase space are at worst logarithmically divergent

1978-05-15

53

Constructing mammography examination process ontology using affinity diagram and hierarchical task analysis.  

Science.gov (United States)

Mammography is complex and difficult for beginner radiologic technologists (RTs) because knowledge and technical skills rely on one's experience, and it is often difficult for experienced RTs to verbally explain the process to co-workers or beginners. The purpose of this study was to construct a mammography examination process ontology for knowledge sharing among RTs and propose a new ontology construction method using an affinity diagram (AD) and hierarchical task analysis (HTA). First, tasks collected by brainstorming were clustered and connected using the AD. Subsequently, a hierarchical structure was constructed based on the clusters and relations determined in the AD. Finally, a mammography process ontology was determined based on the relations noted in the AD and HTA. As a result, the ontology contained 203 classes and 669 relations. PMID:23920833

Yagahara, Ayako; Tsuji, Shintarou; Fukuda, Akihisa; Yokooka, Yuki; Nishimoto, Naoki; Kurowarabi, Kunio; Ogasawara, Katsuhiko

2013-01-01

54

Constructing mammography examination process ontology using affinity diagram and hierarchical task analysis.  

UK PubMed Central (United Kingdom)

Mammography is complex and difficult for beginner radiologic technologists (RTs) because knowledge and technical skills rely on one's experience, and it is often difficult for experienced RTs to verbally explain the process to co-workers or beginners. The purpose of this study was to construct a mammography examination process ontology for knowledge sharing among RTs and propose a new ontology construction method using an affinity diagram (AD) and hierarchical task analysis (HTA). First, tasks collected by brainstorming were clustered and connected using the AD. Subsequently, a hierarchical structure was constructed based on the clusters and relations determined in the AD. Finally, a mammography process ontology was determined based on the relations noted in the AD and HTA. As a result, the ontology contained 203 classes and 669 relations.

Yagahara A; Tsuji S; Fukuda A; Yokooka Y; Nishimoto N; Kurowarabi K; Ogasawara K

2013-01-01

55

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

International Nuclear Information System (INIS)

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

2007-10-05

56

CONVERSIÓN DE DIAGRAMAS DE PROCESOS EN DIAGRAMAS DE CASOS DE USO USANDO AToM³/ CONVERSION OF PROCESSES DIAGRAMS IN USE CASE DIAGRAMS USING AToM³  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish Toda pieza de software se origina en el modelo verbal, con el cual se pueden definir los diferentes modelos conceptuales que acerquen el problema a una solución. Las herramientas convencionales para la construcción de los modelos conceptuales no toman en consideración las diferentes reglas de consistencia que se pueden presentar entre los diferentes modelos. En este artículo se emplea el AToM³ como herramienta para la definición de los meta-modelos del diagrama de p (more) rocesos y el diagrama de casos de uso, con el fin de reexpresar el primero para obtener algunos elementos básicos del segundo. Abstract in english Every software piece has its origins in the verbal model. With this model, it?s possible to define several conceptual models that allow reaching a solution closer to the problem. Conventional tools for conceptual model building don?t take into account the different consistency rules between different models. In this paper we use AToM³ as a tool for the meta-models? definition of process diagram and use case diagrams, trying to redefine the first to obtain some basic elements from the second.

ZAPATA J., CARLOS M.; ÁLVAREZ., CARLOS ALBERTO

2005-07-01

57

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

Directory of Open Access Journals (Sweden)

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

MIOARA UDRIC?; TEODORA V?TUIU; ADRIAN GHENCEA

2011-01-01

58

Stereo Diagrams  

Science.gov (United States)

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.

Perkins, Dexter

59

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

Energy Technology Data Exchange (ETDEWEB)

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.

Timmerman, R.D.; Burns, T.J.; Dodds, H.L. Jr.

1984-01-01

60

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

Directory of Open Access Journals (Sweden)

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.

Mostafa M. Gomaa

2011-01-01

 
 
 
 
61

Chemical reactions and processes under flow conditions  

CERN Multimedia

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

Luis, Santiago V; Clark, James H

2009-01-01

62

Business process management with FlowMark  

UK PubMed Central (United Kingdom)

From an enterprise point of view the management of business processes is becoming increasingly important: Business processes control which piece of work will be performed by whom and which resources are exploited for this work, i.e. a business process describes how an enterprise will achieve its business goals. In this paper we sketch FlowMark (FlowMark is a trademark of IBM), an IBM program product supporting both, the modeling of business processes and their execution.

Frank Leymann; Dieter Roller; Software Development Laboratory

63

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...

64

A comprehensive wiring diagram of the protocerebral bridge for visual information processing in the Drosophila brain.  

UK PubMed Central (United Kingdom)

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.

Lin CY; Chuang CC; Hua TE; Chen CC; Dickson BJ; Greenspan RJ; Chiang AS

2013-05-01

65

Master Logic Diagram: method for hazard and initiating event identification in process plants.  

UK PubMed Central (United Kingdom)

Master Logic Diagram (MLD), a method for identifying events initiating accidents in chemical installations, is presented. MLD is a logic diagram that resembles a fault tree but without the formal mathematical properties of the latter. MLD starts with a Top Event "Loss of Containment" and decomposes it into simpler contributing events. A generic MLD has been developed which may be applied to all chemical installations storing toxic and/or flammable substances. The method is exemplified through its application to an ammonia storage facility.

Papazoglou IA; Aneziris ON

2003-02-01

66

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

Energy Technology Data Exchange (ETDEWEB)

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

Tetreault, T.; Regenthal, S.

2011-05-01

67

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

BORM DiagramsKód oboru RIV: IN - Informatika 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

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

68

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

International Nuclear Information System (INIS)

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

2001-01-01

69

Contribution of radioactive tracers to dynamic modelling of continuous flow processes  

International Nuclear Information System (INIS)

Compilation and structure of the dynamic system model are presented in the form of a sequential flow diagram. Execution of a plant scale tracer study with radioisotopes as a means of the modelling project is described by the same technique with special reference to particulate materials. Contribution of the models to design of various types of control methods and analysis of processes are outlined. (author)

1976-03-09

70

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

International Nuclear Information System (INIS)

The scattering amplitude for the four-rung ladder diagram in ?3 theory is evaluated at high energies and for large momentum transfers. The result takes the form of s-1vertical stroketvertical stroke-3 multiplied by a homogeneous sixth-order polynomial in ln s and 1nvertical stroketvertical stroke. The novel and unexpected feature is that this polynomial is different depending on whether 1n vertical stroketvertical stroke is larger or less than 1/2 1n s. Thus the asymptotic formula is not analytic at 1n vertical stroketvertical stroke=1/2 1n s, although the first five derivatives are continuous. (orig.).

1987-01-01

71

Metastable region of phase diagram: optimum parameter range for processing ultrahigh molecular weight polyethylene blends.  

Science.gov (United States)

Numerous studies suggest that two-phase morphology and thick interface are separately beneficial to the viscosity reduction and mechanical property maintainence of the matrix when normal molecular weight polymer (NMWP) is used for modification of ultrahigh molecular weight polyethylene (UHMWPE). Nevertheless, it is very difficult to obtain a UHMWPE/NMWP blend which may demonstrate both two-phase morphology and thick interface. In this work, dissipative particle dynamics simulations and Flory-Huggins theory are applied in predicting the optimum NMWP and the corresponding conditions, wherein the melt flowability of UHMWPE can be improved while its mechanical properties can also be retained. As is indicated by dissipative particle dynamics simulations and phase diagram calculated from Flory-Huggins theory, too small Flory-Huggins interaction parameter (?) and molecular chain length of NMWP (N(NMWP)) may lead to the formation of a homogeneous phase, whereas very large interfacial tension and thin interfaces might also appear when parameters N(NMWP) and ? are too large. When these parameters are located in the metastable region of the phase diagram, however, two-phase morphology occurs and interfaces of the blends are extremely thick. Therefore, metastable state is found to be advisable for both the viscosity reduction and mechanical property improvement of the UHMWPE/NMWP blends. PMID:22038460

Gai, Jing-Gang; Zuo, Yuan

2011-10-27

72

Metastable region of phase diagram: optimum parameter range for processing ultrahigh molecular weight polyethylene blends.  

UK PubMed Central (United Kingdom)

Numerous studies suggest that two-phase morphology and thick interface are separately beneficial to the viscosity reduction and mechanical property maintainence of the matrix when normal molecular weight polymer (NMWP) is used for modification of ultrahigh molecular weight polyethylene (UHMWPE). Nevertheless, it is very difficult to obtain a UHMWPE/NMWP blend which may demonstrate both two-phase morphology and thick interface. In this work, dissipative particle dynamics simulations and Flory-Huggins theory are applied in predicting the optimum NMWP and the corresponding conditions, wherein the melt flowability of UHMWPE can be improved while its mechanical properties can also be retained. As is indicated by dissipative particle dynamics simulations and phase diagram calculated from Flory-Huggins theory, too small Flory-Huggins interaction parameter (?) and molecular chain length of NMWP (N(NMWP)) may lead to the formation of a homogeneous phase, whereas very large interfacial tension and thin interfaces might also appear when parameters N(NMWP) and ? are too large. When these parameters are located in the metastable region of the phase diagram, however, two-phase morphology occurs and interfaces of the blends are extremely thick. Therefore, metastable state is found to be advisable for both the viscosity reduction and mechanical property improvement of the UHMWPE/NMWP blends.

Gai JG; Zuo Y

2012-06-01

73

Production process flow for healthcare wine  

UK PubMed Central (United Kingdom)

The invention discloses a production process flow for a healthcare wine. The production process flow comprises the following steps of: uniformly stirring powdery burdock and acanthopanax, liquid honey and bee pollen serving as raw materials putting the stirred raw materials into a fermentation container and adding active dry yeast at the same time fermenting in a sealed state for 15 to 25 days after fermenting and filtering fermented raw materials, putting filtered raw materials into distilling equipment putting distilled first wine into the fermentation container filled with the burdock and the acanthopanax adding the honey, the bee pollen, bee glue, royal jelly and queen bee placenta in a certain ratio for immersing after immersing for about 30 days, filtering and distilling, removing precipitate and impurities from the wine to obtain an virgin stock wine and finishing a product after clarified virgin stock wine meets required quality indicators in the production by preparing. The production process flow has the advantages that: due to the adoption of a method which is totally different from a conventional wine making process, the nutrition value of the wine is improved the degree of damage to bodies caused by drinking the wine is reduced and the wine produced by using the process can fulfill the aim of health drinking and is suitable for various drinking occasions, particularly business entertainment and the like.

LI MOU

74

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

Energy Technology Data Exchange (ETDEWEB)

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.

Ning Shuang [Key Laboratory of Liquid Structure and Heredity of Materials, Ministry of Education, Shandong University, Jinan 250061 (China); Bian Xiufang, E-mail: xfbian@sdu.edu.c [Key Laboratory of Liquid Structure and Heredity of Materials, Ministry of Education, Shandong University, Jinan 250061 (China); Ren Zhenfeng [Key Laboratory of Liquid Structure and Heredity of Materials, Ministry of Education, Shandong University, Jinan 250061 (China)

2010-09-01

75

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.

76

Multiphase Flow Modeling of Biofuel Production Processes  

Energy Technology Data Exchange (ETDEWEB)

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

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

2011-06-01

77

Chaos and bifurcation in dynamical evolution process of traffic assignment with flow 'mutation'  

International Nuclear Information System (INIS)

Considering such a fact that the traffic demands freshly entering a network do not have perfect information about traffic condition and may then choose routes randomly, in this paper, we present an improved network traffic flow evolution model. The model's properties and fixed points are investigated. Numerical results obtained from a grid network show that the system can converge to one or more fixed points without requiring of positive route flows at initial time, and can be used to approximately simulate the process of realizing user equilibrium state. It is found that oscillations and such apparently irregular behaviors as chaos occur when the model parameter representing intensity of adjusting route flow and OD demand exceeds some values. Bifurcation diagrams of some route flows and OD demands with respect to this model parameter are presented.

2009-08-15

78

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  

Energy Technology Data Exchange (ETDEWEB)

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 characterized 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.

Murr, L.E. (Oregon Graduate Center, Beaverton (USA)); Wang, S.H. (New Mexico Inst. of Mining and Technology, Socorro (USA))

1982-06-01

79

Digital image processing in flow visualization  

International Nuclear Information System (INIS)

Flow visualization results from the interactions between light and matter. Classical methods such as shadowgraphy, schlieren photography, and interferometry visualize variation in the index of refraction induced by changes in density, pressure, or temperature. Nonuniformities of these physical observables modify the phase of optical waves, rendered visible by free-space propagation (shadowgraphy), optical processing in the back focal plane of a lens (schlieren photography), or interference with a reference wave (interferometry). The classical methods visualize variations of the index of refraction or spatial derivatives thereof integrated along the light path through the fluid. Three-dimensional space is projected onto a plane with the corresponding reduction in degrees of freedom. Except for axial symmetric or two-dimensional flows, spatial structures cannot be recovered from a single image

1988-01-01

80

Solo Diagrams  

UK PubMed Central (United Kingdom)

The calculus of solos is the prex-less subcalculus of the fusioncalculus: it contains only atomic communication actions and theoperators for parallel and scoping. It is expressive enough to admit anencoding of the whole fusion calculus. We here present a graphic representationof agents in the solo calculus, adapting ideas from interactiondiagrams and pi-nets. Our so-called solo diagrams are less complicatedthan these and clarify the important aspects, for example structural congruencein the calculus is precisely isomorphism in the diagrams. Perhapsmost importantly the diagrams contribute to an implementation, replacingthe usual unfolding with a few tractable rules for reducing replicationboxes. Finally we demonstrate the strong similarity with proof nets inlinear logic; it turns out that par and tensor edges have same behaviouras inputs and outputs.1 IntroductionWhen the -calculus was introduced almost fteen years ago one of the mainmotivations was to ...

Cosimo Laneve; Joachim Parrow

 
 
 
 
81

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

82

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

2001-01-01

83

From flows of Lambda Fleming-Viot processes to lookdown processes via flows of partitions  

CERN Document Server

We show that the lookdown process can be pathwise embedded into a stochastic flow of bridges (F_{s,t},s\\leq t) associated to a \\Lambda\\ coalescent. Such a flow of bridges couples an infinite collection of \\Lambda\\ Fleming-Viot processes (\\rho_{s,t},t\\in[s,\\infty))_{s\\in\\mathbb{R}} where \\rho_{s,t} is the probability measure whose distribution function is F_{s,t}. Our pathwise construction yields a collection, indexed by s, of lookdown processes on a shared lookdown graph whose limiting empirical measures are (\\rho_{s,t},t\\in[s,\\infty))_{s \\in \\mathbb{R}}. This construction relies on the introduction of an ancestral types process and a stochastic flow of partitions from the flow of bridges, which are objects of independent interest. We prove that the flow of partitions entirely encodes a lookdown graph. Moreover, this is the unique lookdown graph that couples the infinite collection of \\Lambda\\ Fleming-Viot processes (\\rho_{s,t},t\\in [s,\\infty))_{s\\in \\mathbb{R}}. Finally, in the cases of the Beta(2-\\alpha,\\al...

Labbé, Cyril

2011-01-01

84

Flow processes in a radiant tube burner: Combusting flow  

Energy Technology Data Exchange (ETDEWEB)

Highlights: {yields} 3D combusting flow in an industrial radiant tube burner is modelled using the ANSYS-CFX CFD code. {yields} Results are validated against data from an industrial furnace (NO emissions within 7%). {yields} The flame is long and narrow with slight asymmetry. Mixing near the fuel injector is very effective. {yields} The recuperator section is reasonably effective, but design improvements are proposed. {yields} 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.

Tsioumanis, N., E-mail: nikolaos.tsioumanis@ibp.fraunhofer.d [Fraunhofer IBP, Fraunhoferstrasse 10, Valley, 83626 Bavaria (Germany); Brammer, J.G., E-mail: j.g.brammer@aston.ac.u [School of Engineering and Applied Science, Aston University, Birmingham B4 7ET (United Kingdom); Hubert, J., E-mail: burner.study@wellman-thermal.co [Wellman Furnaces Ltd., New Field Road, Oldbury, West Midlands B69 3ET (United Kingdom)

2011-07-15

85

Phase Diagrams  

Science.gov (United States)

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.

Perkins, Dexter

86

The perceptual flow of phonetic feature processing  

DEFF Research Database (Denmark)

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.

Greenberg, Steven; Christiansen, Thomas Ulrich

2008-01-01

87

Ternary diagram plots  

Energy Technology Data Exchange (ETDEWEB)

A ternary diagram uses an equilateral triangle to graphically depict the relationship among three data values which sum to a constant value. Geologists in many fields use ternary diagrams for a variety of purposes: identification and classification of sedimentary, igneous, and metamorphic rocks; classification of soils; chemical and molecular representation of minerals; representation of the fractional crystallization of igneous rock-forming minerals. Traditionally, constructing a ternary diagram involves calculating the normalized values from the raw data for the three components to be plotted, then plotting the point that represents these values on an equilateral triangle. This can be a tedious and time-consuming process, especially if many samples must be plotted, or many combinations of components represented. Ternary is a program that allows manipulation of large amounts of data to create accurate ternary diagrams. The program allows input of data for hundreds of samples, each containing up to 20 components, any three of which can be combined to form a ternary diagram. Each component can be given a label up to five characters long for ease in identification. Data are entered in raw form (i.e. parts per million, percentages, real or whole numbers), normalized internally to 100, and plotted on a ternary diagram that can be printed to the screen or dot matrix printer.

Scott, A.J.; Guth, P.L.

1987-11-01

88

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

Science.gov (United States)

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

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

89

Biological processes, properties and molecular wiring diagrams of candidate low-penetrance breast cancer susceptibility genes  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Recent advances in whole-genome association studies (WGASs) for human cancer risk are beginning to provide the part lists of low-penetrance susceptibility genes. However, statistical analysis in these studies is complicated by the vast number of genetic variants examined and the weak effects observed, as a result of which constraints must be incorporated into the study design and analytical approach. In this scenario, biological attributes beyond the adjusted statistics generally receive little attention and, more importantly, the fundamental biological characteristics of low-penetrance susceptibility genes have yet to be determined. Methods We applied an integrative approach for identifying candidate low-penetrance breast cancer susceptibility genes, their characteristics and molecular networks through the analysis of diverse sources of biological evidence. Results First, examination of the distribution of Gene Ontology terms in ordered WGAS results identified asymmetrical distribution of Cell Communication and Cell Death processes linked to risk. Second, analysis of 11 different types of molecular or functional relationships in genomic and proteomic data sets defined the "omic" properties of candidate genes: i/ differential expression in tumors relative to normal tissue; ii/ somatic genomic copy number changes correlating with gene expression levels; iii/ differentially expressed across age at diagnosis; and iv/ expression changes after BRCA1 perturbation. Finally, network modeling of the effects of variants on germline gene expression showed higher connectivity than expected by chance between novel candidates and with known susceptibility genes, which supports functional relationships and provides mechanistic hypotheses of risk. Conclusion This study proposes that cell communication and cell death are major biological processes perturbed in risk of breast cancer conferred by low-penetrance variants, and defines the common omic properties, molecular interactions and possible functional effects of candidate genes and proteins.

Bonifaci Núria; Berenguer Antoni; Díez Javier; Reina Oscar; Medina Ignacio; Dopazo Joaquín; Moreno Víctor; Pujana Miguel

2008-01-01

90

Magnetization process and updated phase diagram of one-dimensional S=1 Ising model with single-ion anisotropy under magnetic field  

Science.gov (United States)

By the infinite time-evolving block decimation (iTEBD) technique, the magnetization process in spin-1 Ising model with single-ion anisotropy under external field is investigated in the thermodynamic limit. An updated phase diagram is proposed, and the detailed magnetic structures of the phase diagram are uncovered. It must be noted that two interesting phases with same magnetization plateau (Mz=0) but different magnetic structures are distinguished. Furthermore, they are verified to be an ideal Néel phase and an ideal large-D phase respectively. In addition, a first-order quantum phase transition line between them is determined to be at D=1.

Liu, Guang-Hua; Li, Wei; You, Wen-Long; Su, Gang; Tian, Guang-Shan

2013-07-01

91

Stochastic diagrams and Feynman diagrams  

International Nuclear Information System (INIS)

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

1985-01-01

92

Application of quaternary phase diagrams to compound semiconductor processing. Progress report, April 1, 1988--December 31, 1988.  

Science.gov (United States)

This paper considers the application of quaternary phase diagrams to understanding and predicting the behavior of II-VI thin film interfaces in photovoltaic devices under annealing conditions. Examples, listed in a table, include semiconductor/insulator/s...

A. Schwartzman

1988-01-01

93

Invariances of regularized QED diagrams  

CERN Document Server

We consider properties of connected diagrams with fermion-photon interaction and such fermion and photon propagators and vertex function that the values of these diagrams are finite. We establish the properties of these propagators and vertex function that imply that these diagrams are invariant under C, P, T, CP, CT, PT, or CPT transformations up to some phase factor common to each process. We introduce eight new transformations related to Hermiticity and establish the conditions under which they leave the tree transition probabilities invariant. We determine such general Lorentz form-invariant fermion and photon propagators and fermion-photon vertex functions that make diagrams Lorentz-invariant.

Ribaric, M; Ribaric, Marijan; Sustersic, Luka

2000-01-01

94

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

Science.gov (United States)

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

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

2013-08-01

95

Some limit theorems for flows of branching processes  

CERN Multimedia

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

He, Hui

2012-01-01

96

Contingency diagrams as teaching tools.  

UK PubMed Central (United Kingdom)

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.

Mattaini MA

1995-01-01

97

Contingency diagrams as teaching tools.  

Science.gov (United States)

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. PMID:22478208

Mattaini, M A

1995-01-01

98

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

Directory of Open Access Journals (Sweden)

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.

PALPANDIAN P; Prabhu Raja V; Satish Babu S

2013-01-01

99

ROLE OF UML SEQUENCE DIAGRAM CONSTRUCTS IN OBJECT LIFECYCLE CONCEPT  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 di...

Miroslav Grgec; Robert Mužar

100

Study and resolution of Riemann problem for two-phase flow models. Application for numeric diagrams type Godunov  

International Nuclear Information System (INIS)

[en] In this paper the author presents a study of the Riemann problem for two-phase flow. The results have been used to construct two numerical scheme of Godunov type[fr] On presente une etude du probleme de Riemann pour des modeles d'ecoulements diphasiques avec et sans ecart de vitesse. Les resultats obtenus ont ete utilises pour construire deux schemas numeriques type Godunov: un schema a un etat intermediaire et le schema de ROE

1987-01-01

 
 
 
 
101

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

1988-01-01

102

High-energy, large-momentum-transfer processes: The N-rung ladder diagram of var-phi 3 theory  

International Nuclear Information System (INIS)

The asymptotic form of the amplitude for the N-rung ladder diagram in var-phi 3 theory is calculated in the limit s much-gt |t|much-gt m2. The result is proportional to s-1|t|-N+1 times a homogeneous polynomial of degree 2N-2 in ln s and ln|t|. It is not an analytic function of s and t, although the first N+1 derivatives are continuous in the physical region. Points of nonanalyticity occur when ln|t|=? ln s for ?= (1)/(2) , (1)/(3) ,..., 1/(N-2). The notion of reduced Symanzik functions is introduced. With the aid of these reduced Symanzik functions, a generating function is derived for the leading logarithms of all ladder diagrams.

1991-01-01

103

Control Flow Pattern Recognition for BPMN Process Models  

Directory of Open Access Journals (Sweden)

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

Yeh-Chun Juan; Kuo-Yen Yuan

2013-01-01

104

Phase Diagram of Water  

Science.gov (United States)

An interactive phase diagram of water is presented that allows the user to click on any position on the diagram. A molecular level animation is presented showing the phase(s) represented at the selected position on the diagram.

105

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')??+?-?

1981-01-01

106

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

International Nuclear Information System (INIS)

The form factors of the virtual decays V?P+P' and P?V+P' are calculated under the assumption that the vertex VPP', where V and P are vector and pseudoscalar mesons, is dominated by the anomaly associated with the corresponding quark diagram. The effect of the resulting form factors on the electromagnetic and weak form factors of the P meson is considered. It is shown that the results agree with the predictions of the standard vector-dominance model if the interaction of the photon and W boson with the pseudoscalar mesons is determined by the anomaly of the quark diagram in the ?PP and WPP vertices. A discussion is given of the effect of the form factors of the decay rho??? of a virtual rho meson on the superconvergence of the dispersion relations for the rho??rho? scattering amplitude and on the rho-meson constribution to the ?? scattering length. Rules for calculating quark amplitudes involving any number of mesons are formulated for the examples of the decays ???+?-?0 and eta(eta')??+?-?

1981-01-01

107

Breviz: Visualizing Spreadsheets using Dataflow Diagrams  

CERN Multimedia

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.

Hermans, Felienne; van Deursen, Arie

2011-01-01

108

Automatized material and radioactivity flow control tool in decommissioning process  

International Nuclear Information System (INIS)

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

2009-01-01

109

Analysis of the Flow Pipe Arrangement in RTM Process  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Jinliang Liu; Xiaoqing Wu

110

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

Science.gov (United States)

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.

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

2007-01-01

111

Digital image processing for two-phase flow  

International Nuclear Information System (INIS)

A photographic method to measure the key parameters of two-phase flow is realized by using a digital image processing technique. The 8 bit gray level and 256 x 256 pixels are used to generates the image data which is treated to get the parameters of two-phase flow. It is observed that the key parameters could be identified by treating data obtained by the digital image processing technique

1992-10-31

112

Digital image processing for two-phase flow  

Energy Technology Data Exchange (ETDEWEB)

A photographic method to measure the key parameters of two-phase flow is realized by using a digital image processing technique. The 8 bit gray level and 256 x 256 pixels are used to generates the image data which is treated to get the parameters of two-phase flow. It is observed that the key parameters could be identified by treating data obtained by the digital image processing technique.

Lee, Jae Young; Lim, Jae Yun [Cheju National University, Cheju (Korea, Republic of); No, Hee Cheon [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

1992-07-01

113

Stochastic equations, flows and measure-valued processes  

CERN Multimedia

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

Dawson, Donald A

2010-01-01

114

FlowSim/FlowRisk: A code system for studying risk associated with material process flows  

Energy Technology Data Exchange (ETDEWEB)

The need to study and assess life-cycle risks of Pu release by nuclear warheads during peace time lead to the development of a code suite which could model day to day operations involving nuclear weapons and calculate the associated risk involved in these proceedings. The life-cycle study called LIONSHARE is described in Reference 1. The code that models the flow is called FlowSim. The code that evaluates the associated risk is called FlowRisk. We shall concentrate here on the methodology used by FlowSim in modeling material flows. FlowRisk, mainly a postprocessor of FlowSim runs, will be dealt with in less detail.

Kaufman, A.M.

1993-10-01

115

A Robust Helical Abrasive Flow Machining (HLX-AFM) Process  

Science.gov (United States)

Abrasive flow machining (AFM) is a fine finishing process in which an abrasives laden semi-solid paste is used for finishing of internal inaccessible recesses or surfaces. Recently, several modifications in the tooling with/without additional machining action have been tried for increasing the material removal in the AFM. The present study is about a novel development in the AFM process, towards the enhancement of material removal rate while polishing the internal cylindrical surfaces. The modified process is termed as helical abrasive flow machining process (HLX-AFM). Taguchi's quality engineering approach has been applied to the developed HLX-AFM process, leading to the optimization of various process parameters and thus the development of a robust machining process with significantly enhanced material removal.

Brar, B. S.; Walia, R. S.; Singh, V. P.; Sharma, M.

2013-01-01

116

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

Energy Technology Data Exchange (ETDEWEB)

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.

Liu, H. H.

2010-09-15

117

Rotating Thermal Flows in Natural and Industrial Processes  

CERN Multimedia

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

Lappa, Marcello

2012-01-01

118

Unsaturated Flow Through a Small Fracture -- Matrix Network: Part 2. Uncertainty in Modeling Flow Processes  

Energy Technology Data Exchange (ETDEWEB)

Simulations of flow and transport in variably saturated fractured rock generally assume equilibrium conditions between the fractures and the porous matrix, leading to predictions that are dominated by a diffusive process. Contrary to these predictions, an increasing body of evidence suggests that fracture-dominated flow, under nonequilibrium conditions between the fractures and porous matrix, occurs frequently in field and laboratory settings. Flow processes, such as fluid cascades and flow path switching, are often observed in laboratory experiments, but are generally not captured by diffusion-based conceptual and numerical models. Many of these processes are assumed to be averaged out at some representative elemental volume scale; however, anecdotal evidence from field experiments conducted at various scales of investigation suggest that this may not be the case. Comparison of experimental observations with numerical simulations illustrates at least two potential problems with standard equivalent continuum and discrete fracture conceptual models of unsaturated fractured and porous media flow. First, such models tend to overestimate the strength of interaction between the fracture and matrix domains. Second, model calibration may allow diffusion-based models to accurately reproduce experimental observations without providing a complete description of the physics governing the system. Failure to incorporate convective transport, reduced fracture–matrix interaction, and other sub-grid-scale processes in models of flow in fractured porous media may result in erroneous descriptions of system behavior.

J.P. Fairley; R.K. Podgorney; T.R. Wood

2004-02-01

119

Shocked similarity collapses and flows in star formation processes  

CERN Multimedia

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

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

2004-01-01

120

Numerical simulation of assisting gas flow for laser cutting process  

Science.gov (United States)

In laser cutting process, an assisting gas is used to improve the mass removal rate from the cutting kerf and protect the kerf surfaces from the high temperature exothermic reactions, such as oxidation reactions, during the cutting process. Numerical simulations are carried out using a commercial CFD code Fluent. In the first part of this work, the behavior of assisting gas flow is computed without heat transfer in laminar model which reveals a vortex structures in the flow at the inlet and exit of the kerf, which may directly affect the surface quality in real gas-laser cutting of metals. The largest vortex, which arises at the channel exit, collects and accumulates the liquid flowing down the channel walls. The study with increasing the angle of the kerf shows that the vortices disappear, and a stable vortex-free attached gas flow is formed. In other side, the heat transfer from the kerf wall to the flow of the assisting gas is important for quality cutting which is carried out in second part of this study including the RNG/?-? model. The kerf wall temperature is kept at 1500K to resemble the laser cutting process. The distance between the nozzle exit and the kerf top surface to nozzle diameter is selected as H=0.7, where H is the stand-off-distance.

Tamsaout, Toufik; Amara, EL-Hachemi

2011-11-01

 
 
 
 
121

Research model of steam-water mixture flow processes  

International Nuclear Information System (INIS)

Large-scale experimental research is described of hydrodynamic and thermodynamic processes in non-adiabatic flow of a steam-water mixture through smooth and internally ribbed channels; the processes significantly affect life and reliability of facilities, such as steam generators, boilers and evaporators. The test equipment and the results obtained are briefly described. Some results are tabulated. The experiments involved both horizontal and vertical tubes. (M.D.). 6 figs

1989-01-01

122

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

Zietsman, Ignatius

123

In-process measurement of polymer melt flow in extrusion process  

Directory of Open Access Journals (Sweden)

Full Text Available Extrusion-based in-process rheometry was carried using a specially designed capillary extrusion die, fitted to a single screw extruder with a screw of 25:1 L/D ratio. A pressure transducer and a thermocouple were attached to the extrusion die. Processing parameters in terms of pressure drop across capillary channel and melt temperature were captured by means of a data acquisition system. Shear properties were quantified using rheometric equations. Baglay corections were made for all sets of data. Cogswell's free convergence model for capillary flow was used to access extensional properties. Comparison of shear flow results from off-line Rosand single bore capillary rheometer and in-process measurement are in good agreement. It is therefore concluded that shear flow for polymer melt in both techniques did not depend on processing history and characteristics of the techniques. Extensional flow results for a linear polymer, HDPE, showed good agreement between the two techniques. However, comparison for flow of branched polymers, LDPE and LLDPE, showed poor agreement. this is attributed to the difference in flow nature between the two techniques. Also degree of chain branching (DCB) plays a significant role on flow behaviour of polymer. Branched materials, such as LDPE and LLDPE, exhibit strain hardening or extensional stress growth behaviour, while linear polymer displays less stress growth during flow.

Charoen Nakason; Sarote Changchum; Manus Saedan

2000-01-01

124

Small scale flow processes in aqueous heterogeneous porous media  

Energy Technology Data Exchange (ETDEWEB)

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.

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

1996-04-01

125

Development of databases and generation of stability diagrams pertaining to the modelling of processes during hot corrosion of heat exchanger components  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the project ''Optimisation of In-Service Performance of Boiler Steels by Modelling High Temperature Corrosion'' (G5RD-CT-2001-00593, acronym OptiCorr) was to establish a set of focused procedures, both in terms of applications of thermochemical standard software and in terms of dedicated new developments, which enable a user to investigate the behaviour of boiler components based on the application of rigorous thermodynamics. Thermodynamic databases which cover the materials involved had to be compiled and assessed in order to be able to apply the appropriate software. Particular new results coming from the databases work will be highlighted. The results of phase equilibrium calculations are shown in appropriate diagrams and compared with published experimental data. The thermochemical standard software FactSage permits the investigation of stoichiometric reactions, complex equilibria and phase diagrams. These calculational capabilities have been applied for the purposes of investigation of (1) the composition of complex combustion gases, (2) metal-gas interactions and (3) metal-gas-molten salt interactions, since these have been established to be the key points for the understanding of the corrosion of heat exchanger components. Selected results from these calculations will be demonstrated and discussed. Application specific software has been developed using the approach of local chemical equilibrium calculated by the programmer's library ChemApp and the add-in ChemSheet for Microsoft EXCEL trademark. Two key processes have been treated: The internal corrosion of the metallic material by diffusion of gases and metals and local phase formation as well as the corrosion of heat exchanger material under a molten salt layer which is in contact with an outer gas phase. The general principles of the code development will be outlined while the details of the programs are given in separate presentations in this volume. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

Hack, K.; Jantzen, T. [GTT-Technologies, Kaiserstrasse 100, D-52134 Herzogenrath (Germany)

2006-03-15

126

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

CERN Multimedia

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...

Vitolins, V; Vitolins, Valdis; Kalnins, Audris

2005-01-01

127

Features, Events, and Processes in UZ Flow and Transport  

Energy Technology Data Exchange (ETDEWEB)

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.

J.E. Houseworth

2001-04-10

128

Features, Events, and Processes in UZ Flow and Transport  

International Nuclear Information System (INIS)

[en] 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

2001-01-01

129

How to calculate one-loop diagrams  

International Nuclear Information System (INIS)

A numerical method to estimate the Feynman integrals for one-loop diagram with on-shell internal particles is described in terms of an antithetic cancellation technique using an adaptive Monte Carlo integration. This method enable the authors to estimate necessary integrals of loop diagrams for physical processes without analytic calculation.

1989-01-01

130

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

International Nuclear Information System (INIS)

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

2000-01-01

131

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

Energy Technology Data Exchange (ETDEWEB)

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

DOE

2000-09-29

132

On-line sample processing methods in flow analysis  

DEFF Research Database (Denmark)

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.

Miró, Manuel; Hansen, Elo Harald

2008-01-01

133

Scattering processes at the high-energy and large-transfer-momentum limit: The asymptotics of phi sup 3 ladder diagrams  

Energy Technology Data Exchange (ETDEWEB)

We study the asymptotics of the PHI{sup 3} diagrams in the high-energy, large-transfer-momentum limit. We derive the asymptotic form for an arbitrary PHI{sup 3} ladder diagram in the leading logarithm approximation. (orig.).

Bergere, M.C. (CEA Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France). Service de Physique Theorique); Szymanowski, L. (Paris-11 Univ., 91 - Orsay (France). Inst. de Physique Nucleaire Siegen Univ. (Gesamthochschule) (Germany, F.R.). Fachbereich 7 - Physik)

1991-02-18

134

Recharge and flow processes in a till aquitard  

DEFF Research Database (Denmark)

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.

SchrØder, Thomas Morville; HØgh Jensen, Karsten

1999-01-01

135

Evaluation of the MODFLOW-2005 Conduit Flow Process.  

UK PubMed Central (United Kingdom)

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%).

Hill ME; Stewart MT; Martin A

2010-07-01

136

Evaluation of the MODFLOW-2005 Conduit Flow Process.  

Science.gov (United States)

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

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

2010-01-22

137

Preface "Nonlinear processes in oceanic and atmospheric flows"  

CERN Multimedia

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

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

2010-01-01

138

Study on two-phase flow using image processing technique  

International Nuclear Information System (INIS)

[en] 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.)

1987-01-01

139

The Akzo-Fina cold flow improvement process  

Energy Technology Data Exchange (ETDEWEB)

The Akzo-Fina CFI process is a very flexible process in which improvement of cold flow properties, desulfurization and hydroconversion are achieved. One of the main characteristics is the dewaxing obtained by the selective hydrocracking of normal paraffins combined with hydro-desulfurization and hydroconversion. Since its introduction in 1988, five licenses have been sold. The units currently run for heavy gasoil upgrading show an excellent performance and reach pour point improvements of over 50[degree]C, long cycle lengths and product sulfur levels well below 0.05 wt%. 2 figs., 2 tabs.

Free, H.W.H.; Schockaert, T.; Sonnemans, J.W.M. (Akzo Chemicals B.V., Amersfoort (Netherlands). Hydroprocessing Catalysts)

1993-09-01

140

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

DEFF Research Database (Denmark)

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.

Fuhrman, David R.; SchlØer, Signe

2013-01-01

 
 
 
 
141

Social network diagram.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A diagram that shows at a glance the social network and support of patients was found useful in a follow-up study of patients with strokes. We believe that the diagram would prove valuable in medical case records and should be an essential part of medical-social reports, particularly for patients at...

Capildeo, R; Court, C; Rose, F C

142

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

Science.gov (United States)

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.

Lisnyi, Bohdan; Stre?ka, Jozef

2013-11-01

143

ROLE OF UML SEQUENCE DIAGRAM CONSTRUCTS IN OBJECT LIFECYCLE CONCEPT  

Directory of Open Access Journals (Sweden)

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.

Miroslav Grgec; Robert Mužar

2007-01-01

144

Radial flow retorting process with trays and downcomers  

Energy Technology Data Exchange (ETDEWEB)

Solid heat carrier material and solid hydrocarbon-containing material, such as oil shale, tar sands or coal, are deflected by conical baffles into radially moving fluid beds which alternately flow radially outwardly and inwardly over a series of trays and downwardly into a series of peripheral and axial downcomers for a sufficient residence time to liberate hydrocarbons from the solid hydrocarbon-containing material. A fluidizing gas is injected upwardly into the beds to mix and fluidize most of the solids in the beds as well as to strip and transport the liberated hydrocarbons away from the beds for further processing downstream. Upright annular baffles can be positioned in the beds to minimize radial backmixing of solids and can also extend above the surface of the beds to minimize wave propagation. Any unfluidized coarse particles can be moved downwardly at an angle of inclination by gravity flow and jet deflectors.

Oltrogge, R.D.

1983-09-13

145

Numerical Modeling of Fluid Flow in the Tape Casting Process  

Science.gov (United States)

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.

Jabbari, Masoud; Hattel, Jesper

2011-09-01

146

Effects of air flow directions on composting process temperature profile.  

Science.gov (United States)

In this study, chicken manure mixed with carnation wastes was composted by using three different air flow directions: R1-sucking (downward), R2-blowing (upward) and R3-mixed. The aim was to find out the most appropriate air flow direction type for composting to provide more homogenous temperature distribution in the reactors. The efficiency of each aeration method was evaluated by monitoring the evolution of parameters such as temperature, moisture content, CO(2) and O(2) ratio in the material and dry material losses. Aeration of the reactors was managed by radial fans. The results showed that R3 resulted in a more homogenous temperature distribution and high dry material loss throughout the composting process. The most heterogeneous temperature distribution and the lowest dry material loss were obtained in R2. PMID:17888646

Kulcu, Recep; Yaldiz, Osman

2007-09-20

147

Effects of air flow directions on composting process temperature profile  

International Nuclear Information System (INIS)

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

2008-01-01

148

Heat and fluid flow in nuclear and process plant safety  

International Nuclear Information System (INIS)

When designing nuclear and process plant, the questions of safety and accident prevention must be given careful consideration. Heat transfer and fluid flow studies are an integral part of the design for all such plant and understanding of these phenomena is vital for safe operation, particularly in fault situations. Papers on recent research, design, and practical applications in this field were presented at a conference organised by the Institution of Mechanical Engineers. This volume, with its emphasis on safety in nuclear plant, provides a review of a topical subject

1983-01-01

149

A traffic flow model for bio-polymerization processes.  

UK PubMed Central (United Kingdom)

Bio-polymerization processes like transcription and translation are central to proper function of a cell. The speed at which the bio-polymer grows is affected both by the number of pauses of elongation machinery, as well the number of bio-polymers due to crowding effects. In order to quantify these effects in fast transcribing ribosome genes, we rigorously show that a classical traffic flow model is the limit of a mean occupancy ODE model. We compare the simulation of this model to a stochastic model and evaluate the combined effect of the polymerase density and the existence of pauses on the instantaneous transcription rate of ribosomal genes.

Davis L; Gedeon T; Gedeon J; Thorenson J

2013-02-01

150

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

International Nuclear Information System (INIS)

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

1981-07-16

151

Identifying flow processes in catchments with porewater isotope profiles  

Science.gov (United States)

Detecting the movement of water in the vadose and saturated zone in catchments is still a challenging task in understanding hydrological processes. Little is known about the interaction between spatial patterns and the subsurface processes to driving forces like precipitation or radiation. Therefore, our study was aimed to gain new insights into the spatial patterns of subsurface processes using porewater stable isotopes profiles. First, we drilled holes to the depth of the soil-bedrock interface at 36 sites and took soil samples of each drill core in 5 cm intervals. The sample locations are situated in the schistous part of the Attert catchment in the Grand Duchy of Luxembourg and can be differentiated according to their topography and vegetation cover into forested hillslopes and grasslands at plateaus and in the riparian zones. The pore water of these soil samples was analyzed for the isotopic composition (?2H and ?18O) with the equilibration method to derive ?D and ?18O values as a function of soil depth. In the next step, we simulated these isotope profiles with a physically based one-dimensional water flow model, where rainfall amount, its isotopic composition, evapotranspiration with the Penman-Monteith equation, and site specific soil physical parameters served as input parameters. Finally, to test interactions between topographical descriptors and the patterns in the isotope profiles, a generalized linear mixed model (GLMM) was applied. The slope, topographic wetness index, elevation, aspect, distance to stream, soil cover, and land use served as physically based variables. A comparison between the observed and modeled isotope profiles allowed for detecting anomalies. The differences between the variation of the measured isotopes on the one hand and the simulated ones on the other hand could be attributed to the following processes: i) mixing of water in the vadose zone due to both, temporally rising groundwater table and input from percolating rainfall water, ii) evaporation processes in the top soil, and iii) subsurface flow along the soil-bedrock interface. Which one of these processes dominated at each site depended on the respective physiographic characteristics. The results of the GLMM supported the hypothesis of an interplay between structural and functional traits. The results suggests that information about the porewater stable isotopic composition across the soil profiles seem to be a promising tool to differentiate between the functional responses and flow pathways in catchments.

Sprenger, Matthias; Gralher, Benjamin; Weiler, Markus

2013-04-01

152

Analysis of the Flow Pipe Arrangement in RTM Process  

Directory of Open Access Journals (Sweden)

Full Text Available 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 gained. The test result shows that: exit velocity had little to do with the length, but the ratio of pipeline diameter. When the diameter of entrance assume value of 6 mm,10mm,16mm and 20mm and the diameter of exit 6 mm, 10mm and 16 mm respectively, the maximum speed should be 694.442 mm per second, 416.667 mm per second and 260.414 mm per second accordingly.

Jinliang Liu; Xiaoqing Wu

2009-01-01

153

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.

2005-01-01

154

Features, Events, and Processes in UZ Flow and Transport  

International Nuclear Information System (INIS)

[en] 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

2004-01-01

155

The process flow and structure of an integrated stroke strategy  

Directory of Open Access Journals (Sweden)

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.

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

2013-01-01

156

The process flow and structure of an integrated stroke strategy.  

UK PubMed Central (United Kingdom)

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.

van Bussel EF; Jeerakathil T; Schrijvers AJ

2013-04-01

157

Flow Process for Electroextraction of Total Proteins from Microalgae.  

UK PubMed Central (United Kingdom)

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

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

2013-04-01

158

Flow process for electroextraction of total proteins from microalgae.  

Science.gov (United States)

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

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

2013-04-11

159

Flow process for electroextraction of total proteins from microalgae.  

UK PubMed Central (United Kingdom)

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

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

2013-10-01

160

Binary Phase Diagram Determinations.  

Science.gov (United States)

The potassium chloride-calcium chloride binary phase diagram was generated from both the theoretical and experimental approach in this laboratory. The theoretical technique was based on a computer evaluation of the excess free energies of the components, ...

F. L. Oetting G. P. Martins C. M. Smith

1985-01-01

 
 
 
 
161

Venn Diagram Shape Sorter  

Science.gov (United States)

This interactive Java applet helps students explore attributes of objects by sorting different sized, colored, shapes into Venn Diagrams. The user chooses the type of Venn Diagram including 2 intersecting circles, 2 non-intersecting circles, or a single circle. Two modes include "make the rule," where users create the rules of the circles and then sort, or "guess the rule," where users attempt to sort the shapes into the circles in order to guess the rule the computer has chosen.

2005-01-01

162

Infiltration condition and mouldability diagram in resin injection moulding  

Directory of Open Access Journals (Sweden)

Full Text Available This paper deals with the modelling of injection moulding processes taking into account the deformability of the preform and the polymerisation of the resin. The coupled flow-deformation problem in the infiltrated and dry region is formulated with the corresponding boundary conditions and with the proper evolution equations determining the motion of the boundaries. An approximated analytical discussion is performed to obtain some estimates on the infiltration velocity, helping in identifying a window of applicability in the parameters space (i.e., the mouldability diagram), which fits well with the numerical simulations.

Luca Mesin

2007-01-01

163

Infiltration condition and mouldability diagram in resin injection moulding  

Scientific Electronic Library Online (English)

Full Text Available Abstract in english This paper deals with the modelling of injection moulding processes taking into account the deformability of the preform and the polymerisation of the resin. The coupled flow-deformation problem in the infiltrated and dry region is formulated with the corresponding boundary conditions and with the proper evolution equations determining the motion of the boundaries. An approximated analytical discussion is performed to obtain some estimates on the infiltration velocity, he (more) lping in identifying a window of applicability in the parameters space (i.e., the mouldability diagram), which fits well with the numerical simulations.

Mesin, Luca

2007-01-01

164

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

Energy Technology Data Exchange (ETDEWEB)

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).

E.L. Hardin

2000-07-17

165

Feynman Diagrams and Lax Pair Equations  

CERN Multimedia

We find a Lax pair equation corresponding to the Connes-Kreimer Birkhoff factorization of the character group of the Hopf algebra of Feynman diagrams. In particular, we obtain a flow for the character given by Feynman rules, and present a worked example.

Baditoiu, G; Baditoiu, Gabriel; Rosenberg, Steven

2006-01-01

166

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)

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.

Lin, Sui

2009-03-01

167

Features, Events, and Processes in SZ Flow and Transport  

Energy Technology Data Exchange (ETDEWEB)

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).

S. Kuzio

2005-08-20

168

Features, Events, and Processes in SZ Flow and Transport  

Energy Technology Data Exchange (ETDEWEB)

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).

K. Economy

2004-11-16

169

Manufacturing process planning optimisation in reconfigurable multiple parts flow lines  

Directory of Open Access Journals (Sweden)

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.

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

2008-01-01

170

Development of the mist flow process. Final report  

Energy Technology Data Exchange (ETDEWEB)

The Mist Flow Ocean Thermal Energy Process is a practical method for exploiting the ocean temperature difference without using heat exchangers or large vapor turbines. Warm ocean surface water is sprayed upward into the bottom of an evacuated vertical duct. Vapor flashes from the sprayed water droplets and drags them upward as it proceeds to the top of the duct. There the vapor is condensed by cold water obtained from the depths. The validity of the concept has been demonstrated in a set of experiments conducted in a 4-meter tall transparent test column of 23 x 36 cm cross section. The coupling between the vapor and the droplets remained strong as energy equivalent to over 60 meters of lift was transferred from the vapor to the water droplets.

Ridgway, S.L.; Hammond, R.P.; Lee, C.K.B.

1981-10-01

171

Weyl card diagrams  

International Nuclear Information System (INIS)

To capture important physical properties of a spacetime we construct a new diagram, the card diagram, which accurately draws generalized Weyl spacetimes in arbitrary dimensions by encoding their global spacetime structure, singularities, horizons, and some aspects of causal structure including null infinity. Card diagrams draw only nontrivial directions providing a clearer picture of the geometric features of spacetimes as compared to Penrose diagrams, and can change continuously as a function of the geometric parameters. One of our main results is to describe how Weyl rods are traversable horizons and the entirety of the spacetime can be mapped out. We review Weyl techniques and as examples we systematically discuss properties of a variety of solutions including Kerr-Newman black holes, black rings, expanding bubbles, and recent spacelike-brane solutions. Families of solutions will share qualitatively similar cards. In addition we show how card diagrams not only capture information about a geometry but also its analytic continuations by providing a geometric picture of analytic continuation. Weyl techniques are generalized to higher dimensional charged solutions and applied to generate perturbations of bubble and S-brane solutions by Israel-Khan rods.

2005-06-15

172

Qualitative Assessment of Flow and Transport Mechanisms in Bioremediation Processes  

Science.gov (United States)

Recent studies suggest that time-lapse crosshole geophysical methods may be effective in monitoring subsurface hydrological and biochemical mechanisms. These methods have potential to provide a minimally invasive, cost-effective, high resolution, field relevant means to gain information previously limited to wellbore data. Our study area is located at a DOE Hanford site, an area heavily polluted with toxic chromate. Time- lapse crosshole seismic and radar data sets have been collected in order to monitor spatio-temporal responses to these processes. Before using these data for parameter estimation and monitoring hydrobiogeochemical processes, we need to 1) identify the critical parameters involved in these processes; 2) determine the sensitivity of seismic/radar responses to these parameters; and 3) choose the most appropriate forward modeling approach for forward and inverse modeling. In this study, we treat critical parameters (e.g., hydraulic conductivity, flow rate, and the dispersion coefficients) as random variables, which can be described by their probabilistic density distributions. Then we adopt stochastic sampling method within the Minimum relative entropy (MRE) framework to generate many realistic models based on the welllog data. From here, the geophysical (crosshole seismic and radar) responses are computed using different forward models to study the sensitivity of the responses to those aforementioned parameters, and the performances of the different forward modeling approaches are compared. Finally, geophysical data are used for hydrobiogeochemical parameter estimation through Bayesian inverse modeling. Our study provides guidance on favorable situations in which borehole geophysical data can be effectively used for monitoring subsurface hydrobiogeochemical processes.

Terry, N.; Hou, Z.

2008-12-01

173

SEVERAL GAS FLOW MEASURING DEVICES AND SIGNAL PROCESSING METHODS  

UK PubMed Central (United Kingdom)

A gas flow receiver has a non-symmetrical-flow-inducing diaphragm mounted in a flow tube and causes non-symmetrical flow in the flow tube with an accentuated higher pressure near an upstream orifice than would be sensed in a corresponding cross-section of the flow tube and an accentuated lower pressure near a downstream orifice. A gas flowmeter using thermoanemometer-type transducers receiving gas flow from the upstream orifice is made immune to vibration or acceleration by arranging a pair of the transducers parallel to one another with the gas flow passing serially through them, but in opposite directions. The transducer output is amplified by a noisy amplifier which injects a secondary signal prior to digital conversion using an ADC. The digital signal is averaged over a sampling period to obtain a sample having a level of precision greater than a minimum quantization value of the ADC.

GRUDIN Oleg; GENDIN Alexander; FROLOV Gennadiy

174

Diblock copolymer phase diagram  

Science.gov (United States)

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, Ï is the Flory-Huggins Chi Parameter, and N is the length of the block.

Iacovella, Christopher R.

2006-11-20

175

Self Cleaning HEPA Filtration without Interrupting Process Flow  

International Nuclear Information System (INIS)

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

2009-01-01

176

Performance relationship diagrams  

Energy Technology Data Exchange (ETDEWEB)

By describing a business function's cost drivers and graphically depicting the interrelated cost drivers serving as controls and resources to them, a visual performance model can be provided. A graphical technique, called performance relationship diagraming, has been devised that logically describes these cost drivers and their interrelationships. 2 figs.

Cary, M.J.

1991-11-01

177

Process for preparing polypropylene having improved flow property  

International Nuclear Information System (INIS)

[en] Upon exposure to high energy radiation, PP (polypropylene) increases its MI (melt index) greatly, and thereafter the increase usually continued in a gradual and tedious manner. A process is herein provided for improving the flow property of gas-phase-polymerized PP by means of irradiation and stopping the undesirable after-increase of MI. The process comprises irradiating a gas-phase-polymerized PP with a high energy radiation (electron beams, heavy particle beams, neutron beams, gamma-, beta- and X-rays, etc). of 1 to 15 Mrad at 20 to 400C in an O2-containing atmosphere (1 to 25% O2), followed by heating the PP to a temperature from 400C to its melting point for a period of 1 min. to 5 hrs. The product is useful as a molding material ana a foaming material. In one example, a powdery gas-phase-polymerized PP (MI 0.05) was exposed to radiation of 2Mrad in an atmosphere of 21% 02 plus 79% N2, and then heated in the air to 500C for 3 hrs. MI of the PP changed in the atmospheric conditions in the following manner (the embraced are the values given by an irradiated but not heat-treated PP): before irradiation 0.05; 1 day 2.0 (2.0); 2 days 2.0 (2.5); 4 days 2.1 (3:3); 10 days 2.1 (3.6); 20 days 2.1 (3.7). (Kaichi, S.)

1970-01-01

178

Features, Events, and Processes in UZ Flow and Transport  

Energy Technology Data Exchange (ETDEWEB)

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.

P. Persoff

2004-11-06

179

Flow cytometry for the development of biotechnological processes with microalgae.  

UK PubMed Central (United Kingdom)

The current interest in microalgae as a sustainable source of next generation biofuels and other valuable substances is driving exploration of their use as unique biotechnological production systems. To design and optimise appropriate production strategies, the behaviour of particular microalgal species should be well characterised under different culture conditions. Thus, flow cytometric (FCM) methods, which are already well established in environmental and toxicological studies of microalgae, are also useful for analysing the physiological state of microalgae, and have the potential to contribute to the rapid development of feasible bioprocesses. These methods are commonly based on the examination of intrinsic features of individual cells within a population (such as autofluorescence or size). Cells possessing the desired physiological or morphological features, which are detectable with or without fluorescent staining, are counted or isolated (sorted) using an FCM device. The options for implementation of FCM in the development of biotechnological processes detailed in this review are (i) analysing the chemical composition of biomass, (ii) monitoring cellular enzyme activity and cell viability, and (iii) sorting cells to isolate those overproducing the target compound or for the preparation of axenic cultures.

Hyka P; Lickova S; P?ibyl P; Melzoch K; Kovar K

2013-01-01

180

Process effluents from biogas plants. Dynamical cross-flow-filtration; Prozessabwaesser aus Biogasanlagen. Dynamische Cross-Flow-Filtration  

Energy Technology Data Exchange (ETDEWEB)

The authors of the contribution under consideration report on a dynamic cross flow filtration of process sewage from residues of fermentation of agricultural biogas plants. It could be shown that the experimental setup enables the filtration of the liquid phase of a solid-liquid-separation step. A large amount of negative ions such as phosphate or nitrate and a small amount of ammonium ions are held back. The flow through the diaphragm does not depend on the excess pressure on the feed side of the diaphragm. The content of solids as well as the viscosity of the process sewage has an impact on the flow through the diaphragm. The restrictions of material transfer on the flow through the diaphragm could be balanced by means of high rotational speeds and high turbulences on the diaphragm surface. The flow through the diaphragm is a linear function of the rotational speed.

Maas, Robert [Fraunhofer-Inst. fuer Keramische Technologien und Systeme, IKTS Dresden (Germany); Schumann, Ron; Friedrich, Eberhard; Friedrich, Hannelore

2008-12-15

 
 
 
 
181

Cryostat "UV" Relief Valve Selection and Process Flow  

Energy Technology Data Exchange (ETDEWEB)

This report describes the selection of the relief valves for the D-Zero cryostats. The selection was based on the flow requirements calculated in D-Zero engineering note 3740.214,224-EN-6 under fire conditions (1200 F, no vacuum) for the central cryostat; 264 SCFM. This value was calculated from section 5.3.5 of 'Pressure Relief Device Standards; S 1.3-Compressed Gas Storage Containers', published by the Compressed Gas Association, Inc. The flow calculated above is far greater than the required fire condition flow capacity of 264 SCFM. The improbable 70 F flow temperature value of 738 SCFM is still much greater than the required fire capacity. The flow capacity of the paralleled supplemental rupture disc is 2640 SCFM, independently greater than the fire condition flow requirement.

Mulholland, G.T.; Wintercorn, S.J.; /Fermilab

1987-08-11

182

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 leads to the effective and efficient business processrequirement analysis

ATHANASIOS PODARAS; JOSEF MORAVEC; MARTIN PAPIK

2012-01-01

183

Probing the QCD phase diagram with the measurements of $\\phi$-meson production and elliptic flow in the heavy-ion collision at STAR  

CERN Multimedia

We present the measurements of the $\\phi$-meson production and elliptic flow ($v_{2}$) at mid-rapidity in Au + Au collisions at $\\sqrt{s_{NN}}$ = 7.7 - 200 GeV. The data are collected using the STAR detector in the years 2010 and 2011. The energy dependence of nuclear modification factor ($R_{\\rm{CP}}$) of $\\phi$ meson is presented. The $\\phi$-meson $R_{\\rm{CP}}$ has a value $\\geq$ 1.0 for $\\sqrt{s_{NN}}$ $\\leq$ 39 GeV. The $\\Omega/\\phi$ ratios are also presented and show a different trend at the intermediate transverse momentum ($p_{T}$) for $\\sqrt{s_{NN}}$ = 11.5 GeV compared to higher beam energies. The number-of-constituent quark (NCQ) scaling of $v_{2}$ has been studied at various beam energies. The NCQ scaling holds for particles and anti-particles separately including the $\\phi$ meson for $\\sqrt{s_{NN}}$ $\\geq$ 19.6 GeV, which can be considered as an evidence of partonic collectivity. We observe at $\\sqrt{s_{NN}}$ = 7.7 and 11.5 GeV, the $\\phi$-meson $v_{2}$ falls off the trend from the other hadrons a...

,

2013-01-01

184

Power diagrams and their applications  

CERN Multimedia

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

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

2005-01-01

185

Peircean diagrams of time  

DEFF Research Database (Denmark)

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

ØhrstrØm, Peter

2011-01-01

186

Homotopy theory of diagrams  

CERN Document Server

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 properties to those of model categories. They admit homotopy categories (localizations with respect to weak equivalences). They also can be used to construct derived functors by taking the analogs of fibrant and cofibrant replacements. A category with weak equivalences can have several useful model approximations. We take advantage of this possibility and in each situation choose one that suits our needs. In this way we prove all the fundamental properties of the homotopy colimit and limit: Fubini Theorem (the homotopy colimit -respectively limit- c...

Chacholski, W; Chacholski, Wojciech; Scherer, Jerome

2001-01-01

187

Control wiring diagrams  

International Nuclear Information System (INIS)

This paper discusses the changes in electrical document requirements that occur when construction is complete and a generating station starts commercial operation. The needs of operations and maintenance (O and M) personnel are analyzed and contrasted with those of construction to illustrate areas in which the construction documents (drawings, diagrams, and databases) are difficult to use for work at an operating station. The paper discusses the O and M electrical documents that the Arizona Nuclear Power Project (ANPP) believes are most beneficial for the three operating units at Palo Verde; these are control wiring diagrams and an associated document cross-reference list. The benefits offered by these new, station O and M-oriented documents are weighted against the cost of their creation and their impact on drawing maintenance.

1989-01-01

188

Anomalous quark diagrams in the virtual decays V. -->. P+P' and P. -->. V+P' and in related processes  

Energy Technology Data Exchange (ETDEWEB)

The form factors of the virtual decays V..-->..P+P' and P..-->..V+P' are calculated under the assumption that the vertex VPP', where V and P are vector and pseudoscalar mesons, is dominated by the anomaly associated with the corresponding quark diagram. The effect of the resulting form factors on the electromagnetic and weak form factors of the P meson is considered. It is shown that the results agree with the predictions of the standard vector-dominance model if the interaction of the photon and W boson with the pseudoscalar mesons is determined by the anomaly of the quark diagram in the ..gamma..PP and WPP vertices. A discussion is given of the effect of the form factors of the decay rho..--> pi pi.. of a virtual rho meson on the superconvergence of the dispersion relations for the rho..pi -->..rho..pi.. scattering amplitude and on the rho-meson constribution to the ..pi pi.. scattering length. Rules for calculating quark amplitudes involving any number of mesons are formulated for the examples of the decays ..omega --> pi../sup +/..pi../sup -/..pi../sup 0/ and eta(eta')..--> pi../sup +/..pi../sup -/..gamma...

Ivanov, A.N.

1981-06-01

189

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

Energy Technology Data Exchange (ETDEWEB)

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 ..gamma..PP and WPP. The effect of the rho..--> pi pi.. decay form factors for a virtual rho-meson on the superconvergency of the dispersion relations for the rho..pi -->..rho..pi.. scattering amplitude, as well as on the rho-meson contribution to the ..pi pi..-scattering lengths, is discussed. Rules for calculation of quark graphs with an arbitrary number of mesons are formulated for the examples of the decays ..omega --> pi../sup +/..pi../sup -/..pi../sup 0/ and eta(eta')..--> pi../sup +/..pi../sup -/..gamma...

Ivanov, A.N. (Leningradskij Politekhnicheskij Inst. (USSR))

1981-01-01

190

Compressing Binary Decision Diagrams  

DEFF Research Database (Denmark)

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

Hansen, Esben Rune; Satti, Srinivasa Rao

2008-01-01

191

Compressing Binary Decision Diagrams  

CERN Multimedia

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

Hansen, Esben Rune; Tiedemann, Peter

2008-01-01

192

Planar-flow spin casting: Puddle dynamics and process behavior  

Energy Technology Data Exchange (ETDEWEB)

Aluminum is strip cast in air using the planar-flow technique. The solidification puddle is observed directly by high-speed cinematography. Measurement of the puddle length provides a link between the mechanical and thermal problems. Two conclusions are drawn. First, for fixed overpressure, the puddle length varies inversely with the solidificate rate consistent with a pressure-driven flow. Second, the downstream meniscus is flat, consistent with a flow where pressure rise due to solidification (sink of mass) is balanced by pressure drop due to the narrowing cross-section. Dependence of thickness on control parameters is reported.

Ibaraki, T.; Steen, P.H. [Cornell Univ., Ithaca, NY (United States). School of Chemical Engineering

1995-12-31

193

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)

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.

Lin, Sui; Chen, Tzu-Fang

2002-11-01

194

Effect of relaxation processes on initial stages of flow in iron  

International Nuclear Information System (INIS)

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

1979-01-01

195

Flow softening behavior during hot deformation processes of 7005 aluminum alloy at medium strain rate  

Science.gov (United States)

During the hot deformation of 7005 aluminum at medium strain rate of 50s-1, the flow stress curves exhibit continuous flow softening. After the correction for deformation heating, the flow softening still exists at high temperatures. EBSD observations indicate that the remaining softening is associated with grain boundary migration during dynamic recovery process. The flow softening of dynamic grain boundary migration (DGBM) and deformation heating both were removed from the flow stress curves. After ignoring those two flow softening mechanisms, the flow stress curves reach steady state values after its peak value at all deformation temperatures, which are similar with the shape of typical dynamic recovery flow stress curves. It is conclude that in addition to dynamic recovery the deformation heating and DGBM are dominated flow softening mechanisms for 7005 aluminum alloy during hot deformation.

Li, Luoxing; Wang, Guan; Li, Shikang

2013-05-01

196

Stochastic Modelling of Shiroro River Stream flow Process  

Directory of Open Access Journals (Sweden)

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

Musa, J. J

2013-01-01

197

Flow regulation of variable feed pressure stream: process and device  

International Nuclear Information System (INIS)

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

1983-12-09

198

Radiosity with Voronoi Diagrams  

UK PubMed Central (United Kingdom)

Current radiosity methods rely on the calculation of geometric factors, known as formfactors which describe energy exchange between the surfaces of an environment. The most widely used method for storing the illumination across a surface is a mesh of quadrilaterals and/or triangles. For more exact computations these meshes need to be subdivided adaptively. The subdivision methods create artifacts whichhave visible results. A new technique for storing the surface is presented, based on Voronoi diagrams, which are well suited for the task, and can be subdivided without introducing artifacts.

Wolfgang Sturzlinger

199

Influence of surface processes on gas flow in nanoscale capillaries  

International Nuclear Information System (INIS)

Theoretical study of free molecular gas flow in nanoscale capillary taking into account joint effect of different schemes of molecule scattering by the capillary wall and surface diffusion of adsorbed molecules is conducted. The problem of radiation-induced drift of molecules in capillaries is discussed. Influence of adsorbable foreign gases on phase transitions in nanoscale capillaries is considered. (authors).

2009-01-01

200

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.

1994-01-01

 
 
 
 
201

Generalised creep diagram of an open physical system 'metal (alloy) + load + irradiation'  

International Nuclear Information System (INIS)

Generalised creep diagram of an open physical system 'metal (alloy) + load + irradiation' was developed. It is constructed in three axis: temperature, load and density of irradiated particle flux. Details of creeping process are visible from this diagram.

2000-01-01

202

PRACTICAL ASPECTS OF QUALITY ASSURANCE AND IMPROVEMENT IN TROUSERS MANUFACTURING PROCESS  

Directory of Open Access Journals (Sweden)

Full Text Available The paper presents a case-study for trousers manufacturing and more specific, an analysis of quality control system and action plan for improving the quality level. Using data collected in specific check points, the statistical tools as control chart, Pareto diagram, flow chart, histograms, and Fishbone diagram are applied in order to adjust the manufacturing process and improve the quality.

Raluca Brad; Remus Brad

2012-01-01

203

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.

1997-01-01

204

Novel process windows for enabling, accelerating, and uplifting flow chemistry.  

UK PubMed Central (United Kingdom)

Novel Process Windows make use of process conditions that are far from conventional practices. This involves the use of high temperatures, high pressures, high concentrations (solvent-free), new chemical transformations, explosive conditions, and process simplification and integration to boost synthetic chemistry on both the laboratory and production scale. Such harsh reaction conditions can be safely reached in microstructured reactors due to their excellent transport intensification properties. This Review discusses the different routes towards Novel Process Windows and provides several examples for each route grouped into different classes of chemical and process-design intensification.

Hessel V; Kralisch D; Kockmann N; Noël T; Wang Q

2013-05-01

205

Simulations of ductile flow in brittle material processing  

Energy Technology Data Exchange (ETDEWEB)

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.

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

1988-12-01

206

On Deformations of Pasting Diagrams  

CERN Multimedia

We adapt the work of Power to describe general, not-necessarily composable, not-necessarily commutative 2-categorical pasting diagrams and their composable and commutative parts. We provide a deformation theory for pasting diagrams valued in $k$-linear categories, paralleling that provided for diagrams of algebras by Gerstenhaber and Schack, proving the standard results. Along the way, the construction gives rise to a bicategorical analog of the homotopy G-algebras of Gerstenhaber and Voronov.

Yetter, D N

2007-01-01

207

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.

2012-01-01

208

Supporting UML Sequence Diagrams with a Processor Net Approach  

Directory of Open Access Journals (Sweden)

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.

Tony Spiteri Staines

2007-01-01

209

Phase diagram of boron nitride  

Energy Technology Data Exchange (ETDEWEB)

The available data on the phase diagram of boron nitride are reviewed with particular reference to experimental results obtained by Wentorf (1961), Bundy and Wentorf (1963), and Corrigan and Bundy (1975). The polymorphic transformations in the system are then examined using newly obtained experimental thermodynamic characteristics. It is shown, in particular, that the low-temperature region of the phase diagram of BN is essentially different from that of the phase diagram of carbon. A new, more accurate phase diagram of BN is presented. 15 references.

Solozhenko, V.L.

1988-01-01

210

A validation process for multi-phase reacting flow CFD code  

Energy Technology Data Exchange (ETDEWEB)

Computational fluid dynamic (CFD) code calculates flow properties for the analysis of a flow system. Flow properties are computed based on conservation principles and various phenomenological models. The accuracy of the computed flow properties highly depends on the validity of the models and the degree of numerical convergence. Validation of a CFD code is essential for application of an engineering system. Multiphase reacting flows are common in industrial applications and few CFD code are available. A CFD code was developed for the simulation of multiphase reacting flows. A validation process was also developed for such a CFD code. The validation was performed for several cases. Examples of industrial devices which are multiphase reacting flow systems include catalytic cracking reactors, glass melting furnaces, coal-fired combustors, and diesel engines.

Chang, S. L.; Zhou, C. Q.; Petrick, M.

2000-05-09

211

Power Diagram Depth Sorting  

UK PubMed Central (United Kingdom)

In this paper we propose a new approach to thedepth sorting problem. Given a simplicial complexGamma in IEd, our approach is based on the preliminaryconstruction of a convex complex Gammain IEd+1,whose projection on IEdcorresponds to Gamma, and onthe representation of Gammaas a power diagram. Thisapproach exhibits a O(m log m) runtime complexityto sort a simplicial complex with m cells andrequires only linear storage.1 IntroductionThe problem of sorting a set of objects in space accordingto their distance from a given viewpoint hasbeen extensively studied in the literature mainlyfor its important applications in computer graphics.We were interested in this problem becauseits relevance in volume visualization; another areawhere the two-dimensional version of this problemarises is visibility computation on terrains [8].Many techniques exist [3] for the direct visualizationof an unstructured volumetric dataset orgainizedas a tetrahaedral comple...

Paolo Cignoni; Leila De Floriani

212

Tree Diagrams for String Links II: Determining Chord Diagrams  

CERN Multimedia

In previous work, we defined the intersection graph of a chord diagram associated with a string link (as in the theory of finite type invariants). In this paper, we look at the case when this graph is a tree, and we show that in many cases these trees determine the chord diagram (modulo the usual 1-term and 4-term relations).

Mellor, B

2004-01-01

213

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

1980-01-01

214

Recent developments in the uncertainty analysis of flow measurement processes  

Energy Technology Data Exchange (ETDEWEB)

For the evaluation of uncertainties in flow measurement two different documents are used at present. These are the ''Guide to the expression of uncertainty in'' and ISO 5168 . The Guide represents the present state of the art of uncertainty analysis. ISO 5168 is much older, is still under revision and is familiar to most people in the flow community. Although the working methods for evaluating measurement uncertainties are basically the same, the two documents are based on significantly different views on measurement uncertainty. So the dilemma for the experimentalists is whether to use the Guide with which he may not be familiar, or to use ISO/DIS 5168 which is subject to change. This paper discusses the developments in uncertainty analysis in past decades, the agreements and differences between the Guide and ISO 5168, and will illustrate by an example how simple uncertainty analysis can be if all unnecessary terminology can be avoided. From the present analysis the following conclusions are drawn. Currently, the Guide is the only accepted document that is neither expired nor under revision. Uncertainty is a measure for the amount of missing information. If corrections are not applied, information is discarded and the resulting 2s-uncertainty is twice the absolute value of the deviation. (author)

Van der Grinten, J.G.M

1997-07-01

215

Distributed NetFlow Processing Using the Map-Reduce Model  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We study the viability of using the map-reduce model and frameworks for NetFlow data processing. The map-reduce model is an approach to distributed processing that simplifies implementation work, and it can also help in adding fault tolerance to large processing jobs. We design and implement ...

Morken, Jan Tore

216

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

International Nuclear Information System (INIS)

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

1990-01-01

217

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

Directory of Open Access Journals (Sweden)

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.

Jakub Marcin Kupecki; Henryk Anglart; Krzysztof Badyda

2011-01-01

218

Particle Methods for Simulation of Subsurface Multiphase Fluid Flow and Biogeological Processes.  

Science.gov (United States)

A number of particle models that are suitable for simulating multiphase fluid flow and biogeological processes have been developed during the last few decades. Here we discuss three of them: a microscopic model - molecular dynamics; a mesoscopic model - d...

A. Tartakovsky D. Tartakovsky G. Redden P. Meakin T. Scheibe

2007-01-01

219

Pulsed pumping process optimization using a potential flow model.  

Science.gov (United States)

A computational model is applied to the optimization of pulsed pumping systems for efficient in situ remediation of groundwater contaminants. In the pulsed pumping mode of operation, periodic rather than continuous pumping is used. During the pump-off or trapping phase, natural gradient flow transports contaminated groundwater into a treatment zone surrounding a line of injection and extraction wells that transect the contaminant plume. Prior to breakthrough of the contaminated water from the treatment zone, the wells are activated and the pump-on or treatment phase ensues, wherein extracted water is augmented to stimulate pollutant degradation and recirculated for a sufficient period of time to achieve mandated levels of contaminant removal. An important design consideration in pulsed pumping groundwater remediation systems is the pumping schedule adopted to best minimize operational costs for the well grid while still satisfying treatment requirements. Using an analytic two-dimensional potential flow model, optimal pumping frequencies and pumping event durations have been investigated for a set of model aquifer-well systems with different well spacings and well-line lengths, and varying aquifer physical properties. The results for homogeneous systems with greater than five wells and moderate to high pumping rates are reduced to a single, dimensionless correlation. Results for heterogeneous systems are presented graphically in terms of dimensionless parameters to serve as an efficient tool for initial design and selection of the pumping regimen best suited for pulsed pumping operation for a particular well configuration and extraction rate. In the absence of significant retardation or degradation during the pump-off phase, average pumping rates for pulsed operation were found to be greater than the continuous pumping rate required to prevent contaminant breakthrough. PMID:17350717

Tenney, C M; Lastoskie, C M

2007-02-06

220

Online traffic flow model applying dynamic flow-density relation  

International Nuclear Information System (INIS)

[en] 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.)

2002-01-01

 
 
 
 
221

Tree Diagrams for String Links  

CERN Multimedia

In previous work, the author defined the intersection graph of a chord diagram associated with string links (as in the theory of finite type invariants). In this paper, we classify the trees which can be obtained as intersection graphs of string link diagrams.

Mellor, B

2004-01-01

222

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

CERN Multimedia

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

Foucart, Clément

2011-01-01

223

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

Energy Technology Data Exchange (ETDEWEB)

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.

Yortsos, Yanis C.

2002-10-08

224

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

International Nuclear Information System (INIS)

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

2011-01-01

225

Research on automatic optimization of ground control points in image geometric rectification based on Voronoi diagram  

Science.gov (United States)

With the development of remote sensing satellites, the data quantity of remote sensing image is increasing tremendously, which brings a huge workload to the image geometric rectification through manual ground control point (GCP) selections. GCP database is one of the effective methods to cut down manual operation. The GCP loaded from database is generally redundant, which may result in a rectification slowdown. How to automatically optimize these ground control points is a problem that should be resolved urgently. According to the basic theory of geometric rectification and the principle of GCP selection, this paper deeply comprehends some existing methods about automatic optimization of GCP, and puts forward a new method of automatic optimization of GCP based on voronoi diagram to filter ground control points from the overfull ones without manual subjectivity for better accuracy. The paper is organized as follows: First, it clarifies the basic theory of remote sensing image multinomial geometric rectification and the arithmetic of how to get the GCP error. Second, it particularly introduces the voronoi diagram including its origin, development and characteristics, especially the creating process. Third, considering the deficiencies of existing methods about automatic optimization of GCP, the paper presents the idea of applying voronoi diagram to filter GCP in order to complete automatic optimization. During this process, it advances the conception of single GCP's importance value based on voronoi diagram. Then by integrating the GCP error and GCP's importance value, the paper gives the theory and the flow of automatic optimization of GCPs as well. It also presents an example of the application of this method. In the conclusion, it points out the advantages of automatic optimization of GCP based on the voronoi diagram.

Li, Ying; Cheng, Bo

2009-10-01

226

The classification of diagrams in perturbation theory  

Energy Technology Data Exchange (ETDEWEB)

The derivation of scattering equations connecting the amplitudes obtained from diagrammatic expansions is of interest in many branches of physics. One method for deriving such equations is the classification-of-diagrams technique of Taylor. However, as we shall explain in this paper, there are certain points of Taylor`s method which require clarification. First, it is not clear whether Taylor`s original method is equivlant to the simpler classification-of-diagrams scheme used by Thomas, Rinat, Afnan, and Blankleider (TRAB). Second, when the Taylor method is applied to certain problems in a time-dependent perturbation theory it leads to the over-counting of some diagrams. This paper first restates Taylor`s method, in the process uncovering reasons why certain diagrams might be double-counted in the Taylor method. In then explores how far Taylor`s method is equivalent to the simpler TRAB method. Finally, it examines precisely why the double-counting occurs in Taylor`s method and derives corrections which compensate for this double-counting. {copyright} 1995 Academic Press, Inc.

Phillips, D.R.; Afnan, I.R. [School of Physical Sciences, The Flinders University of South Australia, GPO Box 2100, Adelaide 5001 (Australia)

1995-06-01

227

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

International Nuclear Information System (INIS)

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

1999-01-01

228

New developmnts in flow measurement technology provide solutions to difficult process applications  

Energy Technology Data Exchange (ETDEWEB)

This paper describes some new methods developed in the last few years that allow solutions to historically difficult flow measurement applications. Some of these applications are: measuring the flow from a piston pump, long term reliable operation on a process that tends to coat out on the pipeline, monitoring flow in partially-filled lines, and the measurement of fluids with solids in high speed batching applications. The new methods adapt basic electromagnetic flowmeter (magmeter) technology, with new approaches in sensor and electronics design, allowing these difficult applications to succeed. Applicable industries are Chemical, Food & Beverage, Water & Waste, and allied process industries. Successful applications will be cited regarding this topic.

Rose, C.; Vass, G. [Bailey-Fischer & Porter, Warminster, PA (United States)

1995-12-31

229

Effective production of the biodiesel additive STBE by a continuous flow process.  

Science.gov (United States)

A new fuel additive, namely solketal tert-butyl ether (STBE), was developed and optimized under continuous flow conditions using a Corning® Advanced-Flow™ glass reactor. STBE was obtained in two steps from glycerol, a renewable building-block produced in large amount in the processing of biodiesel. The advantages of the highly engineered Corning glass reactor included high mixing and heat-exchange efficiency, chemical resistance under corrosive flow conditions and a small hold-up. A robust, continuous, green and safe industrial-scale process is described. PMID:21840211

Monbaliu, Jean-Christophe M; Winter, Marc; Chevalier, Bérengère; Schmidt, Frank; Jiang, Yi; Hoogendoorn, Ronald; Kousemaker, Michiel A; Stevens, Christian V

2011-07-14

230

Effective production of the biodiesel additive STBE by a continuous flow process.  

UK PubMed Central (United Kingdom)

A new fuel additive, namely solketal tert-butyl ether (STBE), was developed and optimized under continuous flow conditions using a Corning® Advanced-Flow™ glass reactor. STBE was obtained in two steps from glycerol, a renewable building-block produced in large amount in the processing of biodiesel. The advantages of the highly engineered Corning glass reactor included high mixing and heat-exchange efficiency, chemical resistance under corrosive flow conditions and a small hold-up. A robust, continuous, green and safe industrial-scale process is described.

Monbaliu JC; Winter M; Chevalier B; Schmidt F; Jiang Y; Hoogendoorn R; Kousemaker MA; Stevens CV

2011-10-01

231

Process for producing energy from water flowing down a borehole and recovery same  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a system for producing energy from water flow. It comprises: providing a vertical borehole of sufficient depth to convert liquid water to steam through geothermal energy as the water travels theredown; positioning an internal feed pipe into the borehole; providing an air turbine on the upper end of the feed pipe to allow air flowing into the feed pipe to flow through the air turbine; introducing a predetermined quantity of water into the feed pipe below the position of the turbine; allowing the water to flow down the feed pipe and to pull air through the turbine as the water flowed down the pipe; and repeating the step of the process at predetermined timed intervals to provide a substantially constant flow of air through the air turbine.

Daly, O.

1992-03-17

232

Stochastic flows, reaction-diffusion processes, and morphogenesis  

International Nuclear Information System (INIS)

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

1983-01-01

233

Online traffic flow model applying dynamic flow-density relation  

CERN Multimedia

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 fl...

Kim, Y

2002-01-01

234

Multilayer roll bonded aluminium foil: processing, microstructure and flow stress  

International Nuclear Information System (INIS)

Bulk aluminium has been produced by warm-rolling followed by cold-rolling of commercial purity (99% purity) aluminium foil. The bonding appeared perfect from observation with the naked eye, light and transmission electron microscopy. By comparison with bulk aluminium of similar purity (AA1200) rolled to a similar strain (90%RA), the roll-bonded metal showed a much higher density of high-angle grain boundaries, similar strength and improved thermal stability. This study has implications for a number of applications in relation to the processing of aluminium. Roll bonding is of interest as a method for grain size refinement; oxide-containing materials have increased strength, enhanced work-hardening behaviour, and exhibit alterations in recrystallisation behaviour. The behaviour of the hard oxide film is of interest in aluminium processing, and has been investigated by characterising the size and distribution of oxide particles in the roll-bonded samples.

2004-08-02

235

Data crunchers: At processing plants, data flows outpace instrumentation  

Energy Technology Data Exchange (ETDEWEB)

The move away from conventional instrumentation in gas processing plants to devices that provide more diagnostic information about the process as a whole is discussed. Detailed information such as volume and specific gravity on a real time basis allows for quick analysis of natural gas liquids and condensates, while enhancing quality control. Electronics, computerization, as well as more reliable instrumentation combine to produce other benefits as well. For example, more efficient control systems optimize processing equipment, cutting staffing needs, and the more open architecture enables different brands of instrumentation to work together. Challenges still exist, especially in the area of wireless transmission of data to and from remote locations, and in the area of getting devices made by competing manufacturers to 'talk' to each other. Nevertheless, producers are confident about the Ethernet platform's ability to enable various brands of equipment to 'converse'. The advantages of Ethernet which is worldwide in its reach, over Fieldbus, which serves most efficiently as a local area network, are also reviewed.

Budd, G.

2003-04-01

236

The GSP Process - entrained-flow gasification of different types of coal  

Energy Technology Data Exchange (ETDEWEB)

Future Energy GmbH has developed a process for pressure gasification of pulverized solid and pumpable liquid fuels based on partial oxidation in the entrained flow - the so-called GSP Process. The technology was commercialized in 1984 on salty lignite, at Gaskombinat Schwarze Pumpe (Germany). Today the gasifier runs on slurries and waste oil. The Freiberg R & D Centre now has two test facilities each with an entrained-flow gasifier to test gasification processes with a wide variety of coals, to optimize requirements for preparation of feedstock. The paper describes the GSP entrained flow gasifier. It discusses the system of preparing pulverized solid fuels based on pneumatic dense-flow conveyance. Future Energy has developed an atomization nozzle to handle liquid by-products for gasification at Sokolovska uhelna's Autothermal Oil Conversion Plant now under construction. 5 refs., 3 figs., 2 tabs.

Manfred Schingnitz; Friedemann Mehlhose [Future Energy GmbH, Freiberg (Germany)

2005-07-01

237

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

Directory of Open Access Journals (Sweden)

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

Tiago Facchin; Miguel Afonso Sellitto

2008-01-01

238

Particles, Feynman Diagrams and All That  

Science.gov (United States)

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.

Daniel, Michael

2006-01-01

239

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

Directory of Open Access Journals (Sweden)

Full Text Available 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.

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

2007-01-01

240

Circulation diagrams in the analysis of structural ceramic manufacturing process; Analise de fluxos no processo de fabricacao de ceramica vermelha: estudo de caso  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the data corresponding: sampler, draw and analyse in the lay-out of production process in Vale do Rio dos Sinos` industries. It shows a random spatial occupancy and production problems due to the absence of design. The productivity would be improved with a good design. (author) 3 figs.

Soliani, Christina; Machado, Clarice; Santos, Ivana Suely Soares dos; Luersen, Lara [Universidade do Vale do Rio dos Sinos, Sao Leopoldo, RS (Brazil). Centro Tecnologico; Silva, Neli Iloni Warpechowski da [Fundacao de Ciencia e Tecnologia (CIENTEC), Porto Alegre, RS (Brazil)

1995-12-31

 
 
 
 
241

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

1999-08-01

242

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.

1999-01-01

243

New Gas Flow System for Long-Tape Reaction Tube of TFA-MOD Process  

International Nuclear Information System (INIS)

A multi-turning Reel-to-Reel tape conveyance system of the long YBCO coated conductors using TFA-MOD process is desired to be high production rate without large degradation between tape lines. The numerical simulation, which calculated the YBCO growth kinetics, gas element diffusion and gas flow, shown a possibility that the vertical gas flow onto the tape surface realized high production rate of YBCO conductor even on the wider tape. This possibility was also proved by experimental measurements.

2006-06-01

244

A filtered renewal process as a model for a river flow  

Directory of Open Access Journals (Sweden)

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

Lefebvre Mario

2005-01-01

245

Phase diagrams of magnetic nanotubes  

Energy Technology Data Exchange (ETDEWEB)

Analytical expressions for the total magnetic energy of two characteristic internal configurations of nanometric tubes are calculated. A magnetic phase diagram with respect to the aspect ratio of the tubes is obtained which allows a discussion about the possibility of getting ensembles of nanotubes with low coercive fields. A comparison with recently reported coercive fields of three different cobalt nanotube arrays agrees well with the phase diagram derived here.

Escrig, J. [Departamento de Fisica, Universidad de Santiago de Chile, USACH, Av. Ecuador 3493, Santiago (Chile); Landeros, P. [Departamento de Fisica, Universidad de Santiago de Chile, USACH, Av. Ecuador 3493, Santiago (Chile); Altbir, D. [Departamento de Fisica, Universidad de Santiago de Chile, USACH, Av. Ecuador 3493, Santiago (Chile); Vogel, E.E. [Departamento de Ciencias Fisicas, Universidad de la Frontera, Casilla 54-D, Temuco (Chile); Vargas, P. [Departamento de Fisica, Universidad Tecnica Federico Santa Maria, Casilla 110-V, Valparaiso (Chile)]. E-mail: patricio.vargas@usm.cl

2007-01-15

246

Phase diagrams of magnetic nanotubes  

International Nuclear Information System (INIS)

Analytical expressions for the total magnetic energy of two characteristic internal configurations of nanometric tubes are calculated. A magnetic phase diagram with respect to the aspect ratio of the tubes is obtained which allows a discussion about the possibility of getting ensembles of nanotubes with low coercive fields. A comparison with recently reported coercive fields of three different cobalt nanotube arrays agrees well with the phase diagram derived here

2007-01-01

247

Phase diagrams of magnetic nanotubes  

Science.gov (United States)

Analytical expressions for the total magnetic energy of two characteristic internal configurations of nanometric tubes are calculated. A magnetic phase diagram with respect to the aspect ratio of the tubes is obtained which allows a discussion about the possibility of getting ensembles of nanotubes with low coercive fields. A comparison with recently reported coercive fields of three different cobalt nanotube arrays agrees well with the phase diagram derived here.

Escrig, J.; Landeros, P.; Altbir, D.; Vogel, E. E.; Vargas, P.

2007-01-01

248

Introduction to Ternary Phase Diagrams  

Science.gov (United States)

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.

Perkins, Dexter

249

Phase diagrams of the elements  

International Nuclear Information System (INIS)

A summary of the pressure-temperature phase diagrams of the elements is presented, with graphs of the experimentally determined solid-solid phase boundaries and melting curves. Comments, including theoretical discussion, are provided for each diagram. The crystal structure of each solid phase is identified and discussed. This work is aimed at encouraging further experimental and theoretical research on phase transitions in the elements.

1975-01-01

250

Velocity field measurement of flow inside SNOUT of zinc plating process (I)  

Energy Technology Data Exchange (ETDEWEB)

PIV(Particle Image Velocimetry) velocity field measurements inside the snout of al/10 scale model of the Zn plating process were carried out at the strip speed V{sub s}=1.5 m/s. Aluminum powder particles (1{mu}m) and atomized olive oil (3{mu}m) were used as seeding particles to simulate the molten Zinc flow and deoxidisation gas flow, respectively. A pulsed Nd:Yag laser and a 2K X 2K high-resolution CCD camera were synchronized for the PIV velocity field measurement. From flow visualization study, it is found that the liquid flow in the Zn pot is dominantly governed by the uprising flow caused by the rotating sink roll, with its effect on the steel strip inside the snout largely diminished by installing of the snout. The deoxidisation gas flow in front of the strip inside the snout can be characterized by a large-scale vortex rotating clockwise direction formed by the moving strip. In the rear side of the strip, a counter-clockwise vortex is formed and some of the flow entrained by the moving strip impinges on the free surface of molten zinc. The liquid flow in front of the strip is governed by the flow entering the snout, caused by the spinning sink roll. Just below the free surface a counter-clockwise vortex is formed near the snout wall. The moving strip affects dominantly the flow behind the strip inside the snout, and large amount of the liquid flow follows the moving strip toward the sink roll. The thickness of the flow following the strip is very thin in the front side due to the uprising flow, however thick boundary layer is formed in the rear side of the strip. Its thickness is increased as moving downstream toward the sink roll. Inside the snout, the deoxidisation gas flow above the free surface is much faster than the liquid flow in the zinc pot. Due to the larger influx of the flow following the moving strip in the rear side of the strip, higher percentage of imperfection can be anticipated on the rear surface of the strip. (author). 11 refs., 12 figs.

Shin, D.S.; Lee, S.J. [Pohang University of Science and Technology, Pohang (Korea); Choi, J.H. [Pohang University of Science and Technology Graduate School, Pohnag (Korea)

1999-10-01

251

Finding and accessing diagrams in biomedical publications.  

UK PubMed Central (United Kingdom)

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.

Kuhn T; Luong T; Krauthammer M

2012-01-01

252

Eikonal diagrams in multiparton semihard interactions  

International Nuclear Information System (INIS)

[en] We study the set of eikonal diagrams, derived from perturbative QCD, at the lowest order in the coupling constant and with vacuum quantum number exchange, in the three-body interaction of a high-energy parton with two target partons. The contribution to the semihard component of the inelastic cross section is worked out by evaluating the leading behavior of all the dominant cut diagrams. The different cut amplitudes are shown to be proportional to one another, with the same weights of the cutting rules which have been derived in the context of multi-Pomeron exchange. As a consequence of the dominant configuration in the loop integrals, corresponding to the projectile parton on shell between successive interactions, the process is represented by the simplest probabilistic picture, where the three-body interaction is factorized as the product of two-body interaction probabilities

1994-01-01

253

Asteroseismic diagrams for solar-type stars  

CERN Multimedia

We explore the feasibility of applying the Christensen-Dalsgaard diagram to real asteroseismic data and provide quantitative measures of the uncertainty associated with the results. We also propose a new kind of seismic diagram, based on the determination of the locations of sharp acoustic features inside a star. We show that by combining the information about the position of the base of the convective envelope or the HeII ionisation zone with a measure of the average large separation, it is possible to constrain the unknown chemical composition or the various parameters characterising the physical processes in the stellar interior. We demonstrate the application of this technique to the analysis of mock data for a CoRoT target star.

Mazumdar, A

2005-01-01

254

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

Directory of Open Access Journals (Sweden)

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.

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

2013-01-01

255

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

UK PubMed Central (United Kingdom)

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.

He D; Nguyen HC; Hayes-Gill BR; Zhu Y; Crowe JA; Gill C; Clough GF; Morgan SP

2013-01-01

256

Great Plains Gasification Project process stream design data. Final report  

Energy Technology Data Exchange (ETDEWEB)

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

Honea, F.I.

1985-09-01

257

Flow charting for quality improvement.  

UK PubMed Central (United Kingdom)

This article analyzes the merits of flow charts in their relatively new application to healthcare quality management. Specific examples are given that show how a step-by-step diagram can clarify policies and procedures. Patrice Spath explains "imagineering," a technique for problem identification that compares the steps that a process actually follows with a flow chart of what steps the process should follow. In the discrepancies between the two, problems are revealed. Warnings are given that each detail in a flow chart must pertain to its actual subject and that pictorial symbols should be simple and clear. The author lists some software packages that allow flexibility and speed in flow charting. As a tool for discovering redundancies and inefficiencies, the flow chart is a valuable method for refining quality systems.

Spath PL

1991-09-01

258

Continuous-Flow Processes in Heterogeneously Catalyzed Transformations of Biomass Derivatives into Fuels and Chemicals  

Directory of Open Access Journals (Sweden)

Full Text Available Continuous flow chemical processes offer several advantages as compared to batch chemistries. These are particularly relevant in the case of heterogeneously catalyzed transformations of biomass-derived platform molecules into valuable chemicals and fuels. This work is aimed to provide an overview of key continuous flow processes developed to date dealing with a series of transformations of platform chemicals including alcohols, furanics, organic acids and polyols using a wide range of heterogeneous catalysts based on supported metals, solid acids and bifunctional (metal + acidic) materials.

Juan Carlos Serrano-Ruiz; Rafael Luque; Juan Manual Campelo; Antonio A. Romero

2012-01-01

259

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

International Nuclear Information System (INIS)

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

1988-01-01

260

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

Energy Technology Data Exchange (ETDEWEB)

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

Wu, Yu-Shu; Lu, Guoping; Zhang, Keni; Bodvarsson, G.S.

2003-07-15

 
 
 
 
261

PROBLEMS AND TERMS OF THE IMPLEMENTATION OF OPTIMAL FLOW PROCESSES MANAGEMENT  

Directory of Open Access Journals (Sweden)

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.

M. Zinkovsky; I. Dzobko

2012-01-01

262

User's guide to the Variably Saturated Flow (VSF) process to MODFLOW  

Science.gov (United States)

A new process for simulating three-dimensional (3-D) variably saturated flow (VSF) using Richards' equation has been added to the 3-D modular finite-difference ground-water model MODFLOW. Five new packages are presented here as part of the VSF Process--the Richards' Equation Flow (REF1) Package, the Seepage Face (SPF1) Package, the Surface Ponding (PND1) Package, the Surface Evaporation (SEV1) Package, and the Root Zone Evapotranspiration (RZE1) Package. Additionally, a new Adaptive Time-Stepping (ATS1) Package is presented for use by both the Ground-Water Flow (GWF) Process and VSF. The VSF Process allows simulation of flow in unsaturated media above the ground-water zone and facilitates modeling of ground-water/surface-water interactions. Model performance is evaluated by comparison to an analytical solution for one-dimensional (1-D) constant-head infiltration (Dirichlet boundary condition), field experimental data for a 1-D constant-head infiltration, laboratory experimental data for two-dimensional (2-D) constant-flux infiltration (Neumann boundary condition), laboratory experimental data for 2-D transient drainage through a seepage face, and numerical model results (VS2DT) of a 2-D flow-path simulation using realistic surface boundary conditions. A hypothetical 3-D example case also is presented to demonstrate the new capability using periodic boundary conditions (for example, daily precipitation) and varied surface topography over a larger spatial scale (0.133 square kilometer). The new model capabilities retain the modular structure of the MODFLOW code and preserve MODFLOW's existing capabilities as well as compatibility with commercial pre-/post-processors. The overall success of the VSF Process in simulating mixed boundary conditions and variable soil types demonstrates its utility for future hydrologic investigations. This report presents a new flow package implementing the governing equations for variably saturated ground-water flow, four new boundary condition packages unique to unsaturated flow, the Adaptive Time-Stepping Package for use with both the GWF Process and the new VSF Process, detailed descriptions of the input and output files for each package, and six simulation examples verifying model performance.

Thoms, R. Brad; Johnson, Richard L.; Healy, Richard W.

2006-01-01

263

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

Energy Technology Data Exchange (ETDEWEB)

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

Park, Chun Su; Kim, Gun Hong; Hong, Joo Hyoung [Dongkuk Steel Co., Ltd., Pohang (Korea, Republic of); Lee, Myung Hoon; Jeon, Wan Ho [Councurrent Engineering Design Using Intelligent CAE, Seoul (Korea, Republic of)

2007-07-01

264

Measurement of two-phase flow with the digital image processing method  

Energy Technology Data Exchange (ETDEWEB)

This paper discusses the photographic method and digitial image processing technique for the measurement of the void fraction in two-phase flow. A software is developed to measure the void fraction and the interfacial area concentration from the image captured by the camcoder connecting to image capture board in the personal computer. From the careful sensitivity study on the edge detection algorithm, the specific sequential combination of the first derivative convolution algorithm is recommended for two-phase flow under the natural light condition. The coexistance of bright part and dark part in a bubble image due to complex lay scatterring under natural light condition was treated reasonably. The present image processing technique could be used as one of useful tools for the two-phase flow measurement.

Lee, Jae Young; Lee, Kyung Soo; Kim, Young In [Handong Univ., Pohang (Korea, Republic of)

1998-10-01

265

Velocity measurement of three-dimensional flow around rotating parallel disks by digital image processing  

International Nuclear Information System (INIS)

This paper reports a quantitative multi-point velocity measurement system, which is based on particle tracking with the digital image processing technique, which has been developed for analyzing a three-dimensional unsteady flow field. The measurement system consists of two TV cameras, a digital image processor interfaced with personal computer and originally developed algorithm for three dimensional particle tracking. The particles injected into a complex flow field are tracked consecutively, by using the image processing technique which combined with stereo photogrammetry, and three dimensional velocities are automatically calculated. The present method was applied to three-dimensional measurement of swirling flow around or between a rotating coaxial parallel disks. Nearly 5000 instantaneous velocity vectors were extracted from sets of 100 consecutive images and cross-sectional velocity profiles and angular velocity profiles between disks were calculated from these velocity data. The measurement uncertainty involved in the measurement results was about 8%

1989-01-01

266

Measurement of two-phase flow with the digital image processing method  

International Nuclear Information System (INIS)

This paper discusses the photographic method and digitial image processing technique for the measurement of the void fraction in two-phase flow. A software is developed to measure the void fraction and the interfacial area concentration from the image captured by the camcoder connecting to image capture board in the personal computer. From the careful sensitivity study on the edge detection algorithm, the specific sequential combination of the first derivative convolution algorithm is recommended for two-phase flow under the natural light condition. The coexistance of bright part and dark part in a bubble image due to complex lay scatterring under natural light condition was treated reasonably. The present image processing technique could be used as one of useful tools for the two-phase flow measurement

1998-01-01

267

Solid gas reaction phase diagram under high gas pressure  

International Nuclear Information System (INIS)

[en] 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

1992-01-01

268

Centrifugal dewatering and reconstitution of fine coal by the GranuFlow Process  

Energy Technology Data Exchange (ETDEWEB)

A continuous pilot-scale test of the GranuFlow Process was conducted using a screen-bowl centrifuge for the dewatering and reconstitution of column flotation concentrate at a coal preparation plant in Virginia. In this test, a slipstream of the fine-clean-coal slurry from the column flotation concentrate was treated with a bitumen emulsion before dewatering. The treated products from the screen-bowl centrifuge appeared to be dry and in a free-flowing granular form, while the untreated products were wet, sticky, and difficult to handle. Specifically, test results indicated that the average moisture contents of the dewatered coal were 35.7, 35.5, 32.6, 29.9, and 26.5 wt% with Orimulsion additions of 0, 0.7, 3.2, 4.8, and 6.4 wt%, respectively. The handleability and dust reduction of the dewatered coal product were also vastly improved. A preliminary cost estimate of using Orimulsion in the GranuFlow Process is also included. Because of the simplicity of the process and the low cost of the bitumen emulsion, the commercialization potential of the GranuFlow Process is significant.

Wen, W.W.; Utz, B.R.; Killmeyer, R.P. [Dept. of Energy, Pittsburgh, PA (United States). Federal Energy Technology Center

1997-12-31

269

Application of a cold flow model in testing the feasiblity of an oil shale retorting process  

Energy Technology Data Exchange (ETDEWEB)

An oil shale fluid bed process successfully tested in 1.5 ton/day pilot plant in Amoco Research Center is discussed. Emphasis is given on information showing the application of cold flow unit results in the interpretation of retort product yields.

Furlong, M.W.; Tatterson, D.F.; Vasalos, I.A.

1985-01-01

270

Upper Meter Processes: Short Wind Waves, Surface Flow, and Micro- Turbulence.  

Science.gov (United States)

The primary goal of this project is to advance the knowledge of small-scale air-sea interaction processes at the ocean surface, focussing on the dynamics of short waves, the surface flow field and the microturbulence. Since ground truth on the small-scale...

B. Jaehne J. Klinke X. Zhang

1998-01-01

271

Two-phase flow processes with dynamic effects in porous media - parameter estimation and simulation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This study contributes to the understanding of dynamic effects in the capillary pressure-saturation relationship on the local scale and macroscale as well as giving an assessment as to when these effects might need to be taken into account for the evaluation of two-phase flow processes. In a gener...

Manthey, Sabine

272

The transient flow in a centrifugal pump during the discharge valve rapid opening process  

International Nuclear Information System (INIS)

Research highlights: ? DES is suitable for transient performance simulation of pump. ? Rotor-stator interaction phenomenon in transient process is captured. ? The transient performance deviates from the steady performance obviously. ? The flow acceleration and vortics revolution influence pump's transient performance. - Abstract: During the rapid opening period of the discharge valve in the pump system commonly used in nuclear reactor operation, the flow-rate of the pump increases impulsively. In this paper, we report on experiment and numerical simulations which were implemented to investigate the external transient hydrodynamic performance and the internal flow mechanism of the pump during this transient process. External and internal characteristics under different flow-rates were measured with an experimental system. The simulation for steady conditions was based on detached eddy simulation (DES) and sliding mesh was verified by comparing the simulation with test results. More importantly, the transient characteristics during the valve's rapid opening process were simulated using a similar method. Results show that the Q-H curve deviates from the steady-state value. The external characteristics are further explained by analyzing the relative velocity on the middle stream surfaces S1m and S2m between blades. The pump performance during the valve's rapid opening process is influenced both by the fluid acceleration and instantaneous evolutions of the vortex structure.

2010-01-01

273

The Lexis diagram, a misnomer  

Directory of Open Access Journals (Sweden)

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

Vandeschrick Christophe

2001-01-01

274

Random process estimator for laser speckle imaging of cerebral blood flow.  

UK PubMed Central (United Kingdom)

In this paper, we develop a random process theory to explain the laser speckle phenomena. The relation between the probability distribution of speckle's integrated intensity random process Y(t) and the relative velocity v(t) is derived. Based on the random process theory, traditional spatial or temporal laser speckle contrast analysis (i.e. spatial or temporal LASCA) can be derived as the spatial or temporal estimators respectively. Both spatial LASCA and temporal LASCA suffer from noise due to insufficient statistics and nonstationarity in either spatial or temporal domain. Furthermore, either LASCA results in a reduction of spatial or temporal resolution. A new random process estimator is proposed and able to overcome these drawbacks. In an in-vitro study, random process estimator outperforms either spatial LASCA or temporal LASCA by providing much higher SNR (random process estimator vs. spatial LASCA vs. temporal LASCA: 33.64+/-6.87 (mean+/-s.t.d.) vs. 9.08+/-2.85 vs. 3.83+/-1.05). In an in-vivo structural imaging study, random process estimator efficiently suppresses the noise in contrast image and thus improves the distinguishability of small vessels. In a functional imaging study of cerebral blood flow change in the somatosensory cortex induced by rat's hind paw stimulation, random process estimator provides much lower estimation errors in single trial data (random process estimator vs. temporal LASCA: 0.31+/-0.03 vs. 1.36+/-0.09) and finally leads to higher resolution spatiotemporal patterns of cerebral blood flow.

Miao P; Li N; Thakor NV; Tong S

2010-01-01

275

Transformations of triangle ladder diagrams  

CERN Multimedia

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. Acting in the way described in this paper we do not need to use diamond (four-point) diagrams as an intermediate step in deriving relations of arXiv:0803.3420 [hep-th]. In that paper the half-diamonds were related by conformal integral substitution to the diamonds. As is known, the diamonds represent the dual space image of four-point ladder integrals in the four-dimensional momentum space.

Kondrashuk, Igor

2009-01-01

276

Preferential flow processes in unsaturated spoil heaps and heterogeneous mine soils  

Energy Technology Data Exchange (ETDEWEB)

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.

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

2001-07-01

277

Analysis and Design of the Input and Output Attributes of the Dynamic Simulation code for the H2SO4 distillation process  

International Nuclear Information System (INIS)

The dynamic simulation code for the H2SO4 distillation process was developed by the KAERI research group in 2007. The analysis and design of the input and output attributes are usually required for the effective compilation of the dynamic simulation program. The Data Flow Diagram (DFD) and the class diagram have been used for the analysis and design of the input and output attributes. In this paper, the data flows for dynamic simulation of the H2SO4 distillation process have been embodied by using the DFD and the input and output attributes have also been defined by using the class diagram

2009-01-01

278

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

Energy Technology Data Exchange (ETDEWEB)

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

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

2009-10-15

279

A Control-flow Pattern based Horizontal Business Process Model Transformation Approach  

Directory of Open Access Journals (Sweden)

Full Text Available Due to company mergers and business to business interoperability, there is a need for model transformations in the area of business process modeling to facilitate scenarios like model integration and model synchronization. General model transformation approaches do not consider the special properties of business process models and horizontal transformation scenarios. Since different business process modeling languages use different modeling elements and syntax constraints, a business process may have very different representations in different languages. So in many cases it is not easy to transform business process models correctly only using an element-2-element mapping. In order to solve this problem and improve the correction rate of horizontal business process model transformation, in this work we propose CP-BPMT(Control-flow Pattern based Business Process Model Transformation), a horizontal business process model transformation approach in which the operation granularity has been increased from model elements to model fragments illustrating certain control-flow patterns. CP-BPMT is feasible in practice and it can generate transformation results better than element-based approaches. In order to illustrate CP-BPMT approach, a UML-AD2YAWL case study is conducted.

Zhaogang Han; Zhang Li; Huang Wenqing; Gang Wang

2013-01-01

280

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

Directory of Open Access Journals (Sweden)

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

SMITA ACHARYA, PRAGATI GUPTA, M.A.MUJAWAR

2013-01-01

 
 
 
 
281

Deriving bedform phase diagrams  

Science.gov (United States)

Students prepare for this activity by working with a unidirectional flume with a sand bed. We adjust water depth, flow velocity, and channel slope to achieve a range of bed states, in an effort for them to understand the controls on bedforms. This portion of the activity could be done in lecture or via another exercise that makes use of digital video of actual experiments. The activity itself is a jigsaw: students form groups of three, each group responsible for plotting depth vs. velocity plots of bedform state for a single sand grain size range (0.10-0.14 mm, 0.5-0.64 mm, and 1.3-1.8 mm). These data are provided to them as Excel files and the data were directly 'stolen' from the original depth vs. velocity plots in Middleton and Southard (1984), Mechanics of Sediment Movement, SEPM Short Course Number 3. Datathief software (available free on the web) was used to steal the data. The data are arranged in columns: depth, velocity, and bedform type. Students must plot each of the different bedform types with a different symbol, then they have to define field boundaries. It is critical that they have never seen the original plots in their textbook. The goal is for them to derive them on their own, not to regurgitate what is in their textbook or elsewhere. After they complete their plots for each grain size range, the groups re-arrange themselves into groups of three with one representative from each of the grain size groups. They then must try to evaluate the effects of changing grain size on bedform state. Finally, after completing the exercise, the bedform analysis is linked to the cross stratification that is produced under conditions of high sediment fallout rates and the given bed state. The activity gives students practice working with realistic datasets, exposure to the role of physical modeling in sedimentary geology, and a chance to plot and interpret real data. Furthermore, it really solidifies the link between cross stratification and its dynamic interpretation from the rock record.

Hickson, Thomas

282

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

Directory of Open Access Journals (Sweden)

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

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

2007-01-01

283

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

Energy Technology Data Exchange (ETDEWEB)

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.

Yannis C. Yortsos

2003-02-01

284

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

Directory of Open Access Journals (Sweden)

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

H. Matysiak; R. Haratym; M. Klabczyk

2009-01-01

285

Improving Web Database Access Using Decision Diagrams  

CERN Multimedia

In some areas of management and commerce, especially in Electronic commerce (E-commerce), that are accelerated by advances in Web technologies, it is essential to support the decision making process using formal methods. Among the problems of E-commerce applications: reducing the time of data access so that huge databases can be searched quickly; decreasing the cost of database design ... etc. We present the application of Decision Diagrams design using Information Theory approach to improve database access speeds. We show that such utilization provides systematic and visual ways of applying Decision Making methods to simplify complex Web engineering problems.

Popel, D V; Popel, Denis V.; Al-Hakeem, Nawar

2002-01-01

286

Grid diagrams and Khovanov homology  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We explain how to compute the Jones polynomial of a link from one of its grid diagrams and we observe a connection between Bigelow’s homological definition of the Jones polynomial and Kauffman’s definition of the Jones polynomial. Consequently, we prove that the Maslov grading on the Seidel–Smith sy...

Droz, J-M; Wagner, E

287

Electrical elementary diagrams and operators  

Energy Technology Data Exchange (ETDEWEB)

After 40 years of reading and interrupting electrical elementary logic drawings, I have concluded that we need to make a change. We need to write and express our nuclear power plant logic in some other language than relay ladder logic, solid state logic or computer mnemonics. The language should be English, or your native language, and the format should be Descriptive Block Diagrams. (author)

Patterson, B.K. [Human Factors Practical Inc., Dipper Harbour, New Brunswick (Canada)]. E-mail: HumanFactors@netscape.ca

2005-07-01

288

The diagram for phyllotactic series  

Directory of Open Access Journals (Sweden)

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

Joanna Szymanowska-Pu?ka; Wies?aw W?och

1997-01-01

289

Phase diagrams of mesomorphic mixtures  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We have combined the Maier Saupe theory [1] of the nematic-isotropic transition and the Flory Huggins theory of mixtures to describe the phase diagrams of two nematogens A + B. The two components can have different order parameters SA, SB in the mixture. We can then predict the morphology of the pha...

Brochard, F.; Jouffroy, J.; Levinson, P.

290

Transformation of BPMN Diagrams to YAWL Nets  

Directory of Open Access Journals (Sweden)

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.

Jianhong Ye; Wen Song

2010-01-01

291

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

International Nuclear Information System (INIS)

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

2005-01-01

292

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

Directory of Open Access Journals (Sweden)

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

Roger T. Staff; Trevor S. Ahearn; Louise H. Phillips; Clare Scott; Donald Mowat; Claude Wischik; Lawrence J. Whalley; Alison D. Murray

2011-01-01

293

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

International Nuclear Information System (INIS)

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

1999-01-01

294

Basics of introduction to Feynman diagrams and electroweak interactions physics  

International Nuclear Information System (INIS)

The Feynman diagrams are the main computational method for the evaluation of the matrix elements of different processes. Although it is a perturbative method, its significance is not restricted to perturbation theory only. In this book, the elements of quantum field theory, the Feynman diagram method, the theory of electroweak interactions and other topics are discussed. A number of classical weak and electroweak processes are considered in details. This involves, first of all, the construction of the matrix elements of the process using both the Feynman diagram method (when perturbation theory can be applied) and the invariance principles (when perturbation theory fails). Then the cross sections and the decay probabilities are computed. The text is providing widely used computational techniques and some experimental data. (A.B.). 32 refs., 7 appendix.

1994-01-01

295

Basics of introduction to Feynman diagrams and electroweak interactions physics  

Energy Technology Data Exchange (ETDEWEB)

The Feynman diagrams are the main computational method for the evaluation of the matrix elements of different processes. Although it is a perturbative method, its significance is not restricted to perturbation theory only. In this book, the elements of quantum field theory, the Feynman diagram method, the theory of electroweak interactions and other topics are discussed. A number of classical weak and electroweak processes are considered in details. This involves, first of all, the construction of the matrix elements of the process using both the Feynman diagram method (when perturbation theory can be applied) and the invariance principles (when perturbation theory fails). Then the cross sections and the decay probabilities are computed. The text is providing widely used computational techniques and some experimental data. (A.B.). 32 refs., 7 appendix.

Bilenky, S.M. [Joint Inst. for Nuclear Research, Dubna (Russian Federation); Mikhov, S.G. [Institute for Nuclear Research, Sofia (Bulgaria)

1994-12-31

296

Application of a cold flow model in testing the feasibility of an oil shale retorting process  

Energy Technology Data Exchange (ETDEWEB)

An oil shale fluid bed process was successfully tested in a 1.5 tons/day retort. A pilot plant previously used for catalytic cracking studies was modified for this purpose. The successful conversion of the existing pilot plant to a retort and the remarkably smooth startup and operation were attributed to the concurrent construction and operation of a full-scale cold flow model to test the design of solid feeders and a unique injector/mixer. Operation of the cold flow model over the range of anticipated pilot plant operating conditions provided pressure drop and solids hold data for the mixer. The process was based on rapid heating of small oil shale particles with a hot heat carrier. key to the process was the design of a mixer, of proprietary geometry, which effects rapid interparticle heat transfer, substantial retorting of oil shale, and rapid removal of the hydrocarbon vapors. Several tests were carried out showing that shale oil yields up to 110% of Fisher assay are feasible by using this unique process scheme. In this paper, data are presented showing the application of cold flow results in the interpretation of pilot plant data such as gas and liquid yields.

Vasalos, I.A.; Tatterson, D.F.; Furlong, M.W.; Kowalski, T.L.; So, B.Y.C. (Amoco Research Center, Naperville, IL (US))

1992-06-01

297

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

Energy Technology Data Exchange (ETDEWEB)

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-{center_dot} 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)

Miao, Y.; Hongshuang, D.; Guodong, W.; Xianghua, L. [Northeastern Univ., State Key Lab. of Rolling and Automation, Shenyang City (China)

2000-07-01

298

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)

2000-01-01

299

Tangential filtration with a small motive force during separation of dust-gas flows  

Energy Technology Data Exchange (ETDEWEB)

An approach to formulation of a process for tangential filtration of dust-gas flows is described. Schematic diagrams of structural solutions developed for the filters are discussed. Results are presented for aerodynamic characteristics of the filter for different positions of an adjustable baffle. Basic operational problems are analyzed. The efficiency of the regeneration process is evaluated.

S.Y. Panov; Y.N. Shapovalov; Y.V. Krasovitskii; D.V. Nikitenko; O.A. Panova [Voronezh State Technical Academy (Russian Federation)

2007-07-01

300

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

Directory of Open Access Journals (Sweden)

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.

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

2011-01-01

 
 
 
 
301

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

Scientific Electronic Library Online (English)

Full Text Available Abstract in english 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 (more) 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.

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

2011-09-01

302

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

1999-12-01

303

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

Science.gov (United States)

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

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

2011-03-03

304

Batch-processed carbon nanotube wall as pressure and flow sensor  

Energy Technology Data Exchange (ETDEWEB)

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

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

2010-03-12

305

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

UK PubMed Central (United Kingdom)

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 10(5) 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.

Choi J; Kim J

2010-03-01

306

Direct compression of chitosan: process and formulation factors to improve powder flow and tablet performance.  

UK PubMed Central (United Kingdom)

Chitosan is a polymer derived from chitin that is widely available at relatively low cost, but due to compression challenges it has limited application for the production of direct compression tablets. The aim of this study was to use certain process and formulation variables to improve manufacturing of tablets containing chitosan as bulking agent. Chitosan particle size and flow properties were determined, which included bulk density, tapped density, compressibility and moisture uptake. The effect of process variables (i.e. compression force, punch depth, percentage compaction in a novel double fill compression process) and formulation variables (i.e. type of glidant, citric acid, pectin, coating with Eudragit S®) on chitosan tablet performance (i.e. mass variation, tensile strength, dissolution) was investigated. Moisture content of the chitosan powder, particle size and the inclusion of glidants had a pronounced effect on its flow ability. Varying the percentage compaction during the first cycle of a double fill compression process produced chitosan tablets with more acceptable tensile strength and dissolution rate properties. The inclusion of citric acid and pectin into the formulation significantly decreased the dissolution rate of isoniazid from the tablets due to gel formation. Direct compression of chitosan powder into tablets can be significantly improved by the investigated process and formulation variables as well as applying a double fill compression process.

Buys GM; du Plessis LH; Marais AF; Kotze AF; Hamman JH

2013-06-01

307

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

Energy Technology Data Exchange (ETDEWEB)

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

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

1993-10-01

308

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

Energy Technology Data Exchange (ETDEWEB)

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

Yorstos, Yanis C.

2002-03-11

309

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

Energy Technology Data Exchange (ETDEWEB)

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

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

2000-07-01

310

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

International Nuclear Information System (INIS)

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

2000-01-01

311

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

1986-01-01

312

Direct mapping of algorithms onto VLSI processing arrays based on the data flow approach  

Energy Technology Data Exchange (ETDEWEB)

A new approach to the utilization of VLSI processing arrays by means of the algorithms running on them is presented. The idea is to represent algorithms as data flow graphs, and then map these graphs onto the array. This approach obviates the need to develop new concurrent algorithms to utilize the parallelism inherent in the array, while offering a general environment for the realization of algorithms on semi-custom VLSI. 10 references.

Koren, I.; Silberman, G.M.

1983-01-01

313

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

2005-08-12

314

Generation of powder compaction response diagrams  

Energy Technology Data Exchange (ETDEWEB)

The effect of elastic compliances in the testing system is shown to have a considerable influence on the compaction diagram generated via an automatic procedure. Proper accounting of this effect allows rapid and accurate diagrams to be made.

Matsumoto, R.L.K.

1986-10-01

315

Transport process and reaction scheme on combustion in a stretched, swirling flow  

Energy Technology Data Exchange (ETDEWEB)

The present work deals with modeling turbulent combustion. The objective is to study rotational effects on transport process and reaction scheme in a swirling flow. A figure shows the axially symmetric flow field in an infinitely long tube of radius R. Characteristics of tubular flames for a hydrogen/air mixture have been numerically simulated with detailed transport and finite-rate chemistry. Results show that with increasing circumferential velocity, the inner structure including temperature velocity, the inner structure including temperature and concentration profiles changes. The reaction rate also changes, and the radical concentrations increase radically through the chain process. Since the heat release is offset by formation of the endothermic radicals H, O, and OH in the chain, the temperature change becomes small. In a swirling flow, the pressure decreases around the rotational axis. There arises mass transport due to the pressure gradient. Resultantly, the diffusion velocity of each species is varied, and transport process and chemical scheme are changed. Stretch effect is also intensified due to the accelerated velocity. Through this mechanism, rotational effects appear.

Yamamoto, Kazuhiro

1999-07-01

316

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

Directory of Open Access Journals (Sweden)

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 often 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.

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

2007-01-01

317

Applying Genetic Algorithm for Prioritization of Test Case Scenarios Derived from UML Diagrams  

Directory of Open Access Journals (Sweden)

Full Text Available Software testing involves identifying the test cases which discover errors in the program. However, exhaustive testing of software is very time consuming. In this paper, a technique is proposed to prioritize test case scenarios by identifying the critical path clusters using genetic algorithm. The test case scenarios are derived from the UML activity diagram and state chart diagram. The testing efficiency is optimized by applying the genetic algorithm on the test data. The information flow metric is adopted in this work for calculating the information flow complexity associated with each node of the activity diagram and state chart diagram. If the software requirements change, the software needs to be modified and this requires re - testing of the software. Hence, to take care of requirements change, a stack based approach for assigning weights to the nodes of activity diagram and state chart diagram has also been proposed. In this paper, we have extended our previous work of generating test case scenarios from activity diagram by also considering the concurrent activities in nested activity diagram.

Sangeeta Sabharwal; Ritu Sibal; Chayanika Sharma

2011-01-01

318

The Intersection Graph Conjecture for Loop Diagrams  

CERN Multimedia

Vassiliev invariants can be studied by studying the spaces of chord diagrams associated with singular knots. To these chord diagrams are associated the intersection graphs of the chords. We extend results of Chmutov, Duzhin and Lando to show that these graphs determine the chord diagram if the graph has at most one loop. We also compute the size of the subalgebra generated by these "loop diagrams."

Mellor, B

2000-01-01

319

T-P phase diagram for ice  

International Nuclear Information System (INIS)

In this study we obtain a T-P phase diagram of ice using the mean field theory. We fit our calculated phase line equations to the experimental T-P phase diagram. By choosing appropriately the coefficients in the free-energy expansions, our calculated phase diagram agrees well with the experimentally observed phase diagram of ice. Some thermodynamic functions are calculated using the free energy for the transitions studied here.

2008-01-01

320

Phase diagrams of binary tantalum alloys  

International Nuclear Information System (INIS)

[en] The details of phase diagrams, crystal structures and thermodynamic data of tantalum and all its binary systems are presented in this monograph. Phase diagram illustrations of 52 systems are presented. The complete binary phase diagrams of tantalum with each of the rare earth elements have been presented in detail for the first time. These diagrams have been calculated using a sub-regular solution model

1996-01-01

 
 
 
 
321

Random process estimator for laser speckle imaging of cerebral blood flow  

Science.gov (United States)

In this paper, we develop a random process theory to explain the laser speckle phenomena. The relation between the probability distribution of speckle’s integrated intensity random process Y(t) and the relative velocity v(t) is derived. Based on the random process theory, traditional spatial or temporal laser speckle contrast analysis (i.e. spatial or temporal LASCA) can be derived as the spatial or temporal estimators respectively. Both spatial LASCA and temporal LASCA suffer from noise due to insufficient statistics and nonstationarity in either spatial or temporal domain. Furthermore, either LASCA results in a reduction of spatial or temporal resolution. A new random process estimator is proposed and able to overcome these drawbacks. In an in-vitro study, random process estimator outperforms either spatial LASCA or temporal LASCA by providing much higher SNR (random process estimator vs. spatial LASCA vs. temporal LASCA: 33.64±6.87 ( mean±s.t.d.) vs. 9.08±2.85 vs. 3.83±1.05). In an in-vivo structural imaging study, random process estimator efficiently suppresses the noise in contrast image and thus improves the distinguishability of small vessels. In a functional imaging study of cerebral blood flow change in the somatosensory cortex induced by rat’s hind paw stimulation, random process estimator provides much lower estimation errors in single trial data (random process estimator vs. temporal LASCA: 0.31±0.03 vs. 1.36±0.09) and finally leads to higher resolution spatiotemporal patterns of cerebral blood flow.

Miao, Peng; Li, Nan; Thakor, Nitish V.; Tong, Shanbao

2010-01-01

322

Model Checking Synchronous Timing Diagrams  

UK PubMed Central (United Kingdom)

Model checking is an automated approach to the formal verificationof hardware and software. To allow model checking tools to beused by the hardware or software designers themselves, instead of byverification experts, the tools should support specification methods thatcorrespond closely to the common usage. For hardware systems, timingdiagrams form such a commonly used and visually appealing specificationmethod. In this paper, we introduce a class of synchronous timingdiagrams with a syntax and a formal semantics that is close to the informalusage. We present an efficient, decompositional algorithm for modelchecking such timing diagrams. This algorithm has been implemented ina user-friendly tool called RTDT (the Regular Timing Diagram Translator). We have applied this tool to verify several properties of Lucent'sPCI synthesizable core.1

Nina Amla; E. Allen Emerson; Robert P. Kurshan; Kedar S. Namjoshi

323

Model Checking Synchronous Timing Diagrams  

UK PubMed Central (United Kingdom)

Model checking is an automated approach to the formal verificationof hardware and software. To allow model checking tools to beused by the hardware or software designers themselves, instead of byverification experts, the tools should support specification methods thatcorrespond closely to the common usage. For hardware systems, timingdiagrams form such a commonly used and visually appealing specificationmethod. In this paper, we introduce a class of synchronous timingdiagrams with a syntax and a formal semantics that is close to the informalusage. We present an efficient, decompositional algorithm for modelchecking such timing diagrams. This algorithm has been implemented ina user-friendly tool called RTDT (the Regular Timing Diagram Translator). We have applied this tool to verify several properties of Lucent'sPCI synthesizable core.

Nina Amla; E. Allen Emerson; Robert P. Kurshan; Kedar S. Namjoshi

324

Hero's journey in bifurcation diagram  

Science.gov (United States)

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

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

2012-06-01

325

Grid diagrams of Lorenz links  

CERN Document Server

In paper "A new twist on Lorenz links" (Journal of Topology 2(2009), 227-248) Joan Birman and Ilya Kofman prove the coincidence of the class of Lorenz links and the class of twisted links. The proof in that work is algebraic. We will identify this class in terms of grid diagrams and provide a transparent geometric argument for Birman-Kofman's result.

Razumovsky, Roman

2010-01-01

326

T-X Phase Diagrams  

Science.gov (United States)

This is a 15 page tutorial and problem set designed to get students familiar with T-X diagrams, their implications, and uses. Students start by reading but, after 10-15 minutes, the room becomes noisy as they work their way through the questions at the end. Often there are "Eureka" moments as they all of a sudden grasp some fundamental principles. It is also interesting to hear them try to explain these insights to others.

Perkins, Dexter

327

Phase Diagrams and Chemographic Projections  

Science.gov (United States)

This exercise is a good way to get students thinking about the phase rule, metastable and stable reactions and phase diagrams. The exercise contains a lot of reading, and is suitable for in-class work or for homework. The idea is that students can do this on their own with little help from their instructor. The students only answer a few questions making this is more of a tutorial than a worksheet.

Perkins, Dexter

328

An adaptive optimisation scheme for controlling air flow process with satisfactory transient performance  

Directory of Open Access Journals (Sweden)

Full Text Available A non-identifier-based adaptive PI controller is designed using a gradient approach to improve the performance of a control system when device aging and environmental factors degrade the efficiency of the process. The design approach is based on the model reference adaptive control technique. The controller drives the difference (error) between the process response and desired model output to zero asymptotically at a rate constrained by the desired characteristics of the model. The tuning rules are designed and justified for a non-linear process with dominant dynamics of second order. The advantage of this method for tracking and regulation compared to adaptive MIT control was validated in real time by conducting experiments on a laboratory air flow control system using the dSPACE interface in the SIMULINK software. The experimental results show that the process with adaptive PI controller has better dynamic performance and robustness than that with traditional adaptive MIT controller.

Sivakumar Dakshinamurthy

2010-01-01

329

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

CERN Document Server

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

Zaluska-Kotur, M A; Krukowski, S

2012-01-01

330

Causal diagrams in systems epidemiology  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Methods of diagrammatic modelling have been greatly developed in the past two decades. Outside the context of infectious diseases, systematic use of diagrams in epidemiology has been mainly confined to the analysis of a single link: that between a disease outcome and its proximal determinant(s). Transmitted causes ("causes of causes") tend not to be systematically analysed. The infectious disease epidemiology modelling tradition models the human population in its environment, typically with the exposure-health relationship and the determinants of exposure being considered at individual and group/ecological levels, respectively. Some properties of the resulting systems are quite general, and are seen in unrelated contexts such as biochemical pathways. Confining analysis to a single link misses the opportunity to discover such properties. The structure of a causal diagram is derived from knowledge about how the world works, as well as from statistical evidence. A single diagram can be used to characterise a whole research area, not just a single analysis - although this depends on the degree of consistency of the causal relationships between different populations - and can therefore be used to integrate multiple datasets. Additional advantages of system-wide models include: the use of instrumental variables - now emerging as an important technique in epidemiology in the context of mendelian randomisation, but under-used in the exploitation of "natural experiments"; the explicit use of change models, which have advantages with respect to inferring causation; and in the detection and elucidation of feedback.

Joffe Michael; Gambhir Manoj; Chadeau-Hyam Marc; Vineis Paolo

2012-01-01

331

Tiling groupoids and Bratteli diagrams  

CERN Multimedia

Let T be an aperiodic and repetitive tiling of R^d with finite local complexity. Let O be its tiling space with canonical transversal X. The tiling equivalence relation R_X is the set of pairs of tilings in X which are translates of each others, with a certain (etale) topology. In this paper R_X is reconstructed as a generalized "tail equivalence" on a Bratteli diagram, with its standard AF-relation as a subequivalence relation. Using a generalization of the Anderson-Putnam complex, O is identified with the inverse limit of a sequence of finite CW-complexes. A Bratteli diagram B is built from this sequence, and its set of infinite paths dB is homeomorphic to X. The diagram B is endowed with a horizontal structure: additional edges that encode the adjacencies of patches in T. This allows to define an etale equivalence relation R_B on dB which is homeomorphic to R_X, and contains the AF-relation of "tail equivalence".

Bellissard, J; Savinien, J

2009-01-01

332

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

Science.gov (United States)

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.

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

2001-05-01

333

Applications of the thermal DeNO{sub x} process to FBC boilers  

Energy Technology Data Exchange (ETDEWEB)

This paper presents graphical and tabular information on Exxon Research and Engineering Company`s proprietary NH{sub 3} based selective non-catalytic nitrogen oxides reduction process. The process is applicable to boilers, incinerators, and fired heaters. Process operating parameters, technology, and equipment are outlined. Thermal performance data and simplified flow diagrams are also presented.

McIntyre, A.D. [Exxon Research & Engineering Company, Florham Park, NJ (United States)

1997-12-31

334

PIV quantification of the flow induced by an ultrasonic horn and numerical modeling of the flow and related processing times.  

UK PubMed Central (United Kingdom)

The flow in a confined container induced by an ultrasonic horn is measured by Particle Image Velocimetry (PIV). This flow is caused by acoustic streaming and highly influenced by the presence of cavitation. The jet-like experimentally observed flow is compared with the available theoretical solution for a turbulent free round jet. The similarity between both flows enables a simplified numerical model to be made, whilst the phenomenon is very difficult to simulate otherwise. The numerical model requires only two parameters, i.e. the flow momentum and turbulent kinetic energy at the position of the horn tip. The simulated flow is used as a basis for the calculation of the time required for the entire liquid volume to pass through the active cavitation region.

Schenker MC; Pourquié MJ; Eskin DG; Boersma BJ

2013-01-01

335

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)

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.

M. K. Akhtar; G. A. Corzo; S. J. van Andel; A. Jonoski

2009-01-01

336

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)

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.

M. K. Akhtar; G. A. Corzo; S. J. van Andel; A. Jonoski

2009-01-01

337

Using digital flow cytometry to assess the degradation of three cyanobacteria species after oxidation processes.  

Science.gov (United States)

Depending on drinking water treatment conditions, oxidation processes may result in the degradation of cyanobacteria cells causing the release of toxic metabolites (microcystin), odorous metabolites (MIB, geosmin), or disinfection byproduct precursors. In this study, a digital flow cytometer (FlowCAM(®)) in combination with chlorophyll-a analysis was used to evaluate the ability of ozone, chlorine, chlorine dioxide, and chloramine to damage or lyse cyanobacteria cells added to Colorado River water. Microcystis aeruginosa (MA), Oscillatoria sp. (OSC) and Lyngbya sp. (LYN) were selected for the study due to their occurrence in surface water supplies, metabolite production, and morphology. Results showed that cell damage was observed without complete lysis or fragmentation of the cell membrane under many of the conditions tested. During ozone and chlorine experiments, the unicellular MA was more susceptible to oxidation than the filamentous OSC and LYN. Rate constants were developed based on the loss of chlorophyll-a and oxidant exposure, which showed the oxidants degraded MA, OSC, and LYN according to the order of ozone > chlorine ~ chlorine dioxide > chloramine. Digital and binary images taken by the digital flow cytometer provided qualitative insight regarding cell damage. When applying this information, drinking water utilities can better understand the risk of cell damage or lysis during oxidation processes. PMID:23726712

Wert, Eric C; Dong, Mei Mei; Rosario-Ortiz, Fernando L

2013-05-01

338

Vision Module for Mini-robots Providing Optical Flow Processing for Obstacle Avoidance  

Science.gov (United States)

This paper presents a flexible prototyping platform that can be efficiently used for vision systems of small mobile robots. The vision module has been integrated into the mini-robot “Khepera”. The module is utilized to realize optical flow algorithm for obstacle avoidance. The obstacles are detected from abrupt change of the normal flow vectors during operation. This technique is also inspired by visual perception of insects, which alert when an object suddenly appears nearby them. The optical flow algorithm implemented for this approach is Sum of Absolute Differences (SAD) algorithm. The SAD is programmed using the hardware description language (VHDL) efficiently utilizing the FPGA device that is the central processing device of the module. The 30x16 pixels used in SAD for block matching are computed in parallel by 16 pairs of pixels in each operation, which allows in real-time operation. Therefore, the mini-robot being equipped with our 2D vision module for the real-time image processing is able to drive autonomously without collision with obstacles, called ego-motion. The result also shows that the implementation can reduce the execution time compared to serial implementation and helps to reduce energy consumption.

Chinapirom, Teerapat; Witkowski, Ulf; Rueckert, Ulrich

339

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

Science.gov (United States)

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

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

2012-02-22

340

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

UK PubMed Central (United Kingdom)

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

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

2012-05-01

 
 
 
 
341

Using digital flow cytometry to assess the degradation of three cyanobacteria species after oxidation processes.  

UK PubMed Central (United Kingdom)

Depending on drinking water treatment conditions, oxidation processes may result in the degradation of cyanobacteria cells causing the release of toxic metabolites (microcystin), odorous metabolites (MIB, geosmin), or disinfection byproduct precursors. In this study, a digital flow cytometer (FlowCAM(®)) in combination with chlorophyll-a analysis was used to evaluate the ability of ozone, chlorine, chlorine dioxide, and chloramine to damage or lyse cyanobacteria cells added to Colorado River water. Microcystis aeruginosa (MA), Oscillatoria sp. (OSC) and Lyngbya sp. (LYN) were selected for the study due to their occurrence in surface water supplies, metabolite production, and morphology. Results showed that cell damage was observed without complete lysis or fragmentation of the cell membrane under many of the conditions tested. During ozone and chlorine experiments, the unicellular MA was more susceptible to oxidation than the filamentous OSC and LYN. Rate constants were developed based on the loss of chlorophyll-a and oxidant exposure, which showed the oxidants degraded MA, OSC, and LYN according to the order of ozone > chlorine ~ chlorine dioxide > chloramine. Digital and binary images taken by the digital flow cytometer provided qualitative insight regarding cell damage. When applying this information, drinking water utilities can better understand the risk of cell damage or lysis during oxidation processes.

Wert EC; Dong MM; Rosario-Ortiz FL

2013-07-01

342

Estimating Flow in Streams  

Science.gov (United States)

Presented by West Virginia University, this site addresses flow rates in streams and how to accurately estimate these rates. The site contains thorough diagrams along with solid explanatory text. Overall, the presentation is strong and easily comprehended.

Porter, Dana O.

2008-10-14

343

Resin Flow of an Advanced Grid-Stiffened Composite Structure in the Co-Curing Process  

Science.gov (United States)

The soft-mold aided co-curing process which cures the skin part and ribs part simultaneously was introduced for reducing the cost of advanced grid-stiffened composite structure (AGS). The co-curing process for a typical AGS, preformed by the prepreg AS4/3501-6, was simulated by a finite element program incorporated with the user-subroutines `thermo-chemical' module and the `chemical-flow' module. The variations of temperature, cure degree, resin pressure and fiber volume fraction of the AGS were predicted. It shows that the uniform distributions of temperature, cure degree and viscosity in the AGS would be disturbed by the unique geometrical pattern of AGS. There is an alternation in distribution of resin pressure at the interface between ribs and skin, and the duration time of resin flow is sensitive to the thickness of the AGS. To obtain a desired AGS, the process parameters of the co-curing process should be determined by the geometry of an AGS and the kinds of resin.

Huang, Qizhong; Ren, Mingfa; Chen, Haoran

2013-06-01

344

Measuring concentration with Voronoï diagrams: the study of possible biases  

International Nuclear Information System (INIS)

In the context of turbulent flows laden with inertial particles, the accurate estimation of preferential concentration is particularly relevant. We have recently proposed to use Voronoï diagrams to estimate concentration fields from two-dimensional imaging techniques implemented around wind tunnel experiments. Due to various experimental biases, the relevance of such an analysis becomes questionable. In this paper, we show the robustness of the Voronoï analysis with respect to the three more important identified biases possibly present in such experiments. (paper)

2012-01-01

345

Modeling of temperature field and fluid flow in hybrid welding process  

Directory of Open Access Journals (Sweden)

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.

W. Piekarska; M. Kubiak

2009-01-01

346

FREE-FLOWING PARTICULATE HONEY PRODUCT COMPRISING CRYSTALLISED NATURAL HONEY AND PROCESS FOR PRODUCING THEREOF  

UK PubMed Central (United Kingdom)

The invention provides a free-flowing particulate honey product comprising crystallized natural bee honey and a process for producing thereof. The free flowing particulate honey product comprises crystals of natural honey in admixture with glucose and is characterised by X-ray powder diffraction pattern having peaks in degrees 20 that are identified as characteristic peaks of crystalline glucose monohydrate, and diastase index not less than 90% of the diastase index of a crude honey used to prepare the product, calculated based upon the weight of the crude honey. The product retains all the healthy and biologically active properties of natural honey and can be used as a sugar substitute, or as a component of food mixtures, such as dry cereals, muesli, tea, coffee, drink mixtures, and also for preparing beverages, bakery, confectionary, as well as cosmetic and hygienic formulations.

POLTORATSKY VLADIMIR BORISOVICH; POLTORATSKAYA ALFIA RINATOVNA

347

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

International Nuclear Information System (INIS)

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

2011-01-01

348

Projecting onto Qubit Irreps of Young Diagrams  

CERN Multimedia

Let K be the diagonal subgroup of U(2)^{(x)n}. We may view the one-qubit state-space H_1 as a standard representation of U(2) and the n-qubit state space H_n=(H_1)^{(x) n} as the n-fold tensor product of standard representations. Representation theory then decomposes H_n into irreducible subrepresentations of K parametrized by combinatorial objects known as Young diagrams. We argue that n-1 classically controlled measurement circuits, each a Fredkin-gate interferometer, may be used to form a projection operator onto a random Young diagram irrep within H_n. For H_2, the two irreps happen to be orthogonal and correspond to the symmetric and wedge product. The latter is spanned by ket{Psi^-}, and the standard two-qubit swap interferometer requiring a single Fredkin gate suffices in this case. In the n-qubit case, it is possible to extract many copies of ket{Psi^-}. Thus applying this process using nondestructive Fredkin interferometers allows for the creation of entangled bits (e-bits) using fully mixed states a...

Bullock, S S

2006-01-01

349

Bacterial transformation and biodegradation processes simulation in horizontal subsurface flow constructed wetlands using CWM1-RETRASO.  

UK PubMed Central (United Kingdom)

The performance and reliability of the CWM1-RETRASO model for simulating processes in horizontal subsurface flow constructed wetlands (HSSF CWs) and the relative contribution of different microbial reactions to organic matter (COD) removal in a HSSF CW treating urban wastewater were evaluated. Various different approaches with diverse influent configurations were simulated. According to the simulations, anaerobic processes were more widespread in the simulated wetland and contributed to a higher COD removal rate [72-79%] than anoxic [0-1%] and aerobic reactions [20-27%] did. In all the cases tested, the reaction that most contributed to COD removal was methanogenesis [58-73%]. All results provided by the model were in consonance with literature and experimental field observations, suggesting a good performance and reliability of CWM1-RETRASO. According to the good simulation predictions, CWM1-RETRASO is the first mechanistic model able to successfully simulate the processes described by the CWM1 model in HSSF CWs.

Llorens E; Saaltink MW; Poch M; García J

2011-01-01

350

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

Science.gov (United States)

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

Saito, M.; Onodera, S.

2009-12-01

351

Numerical modeling analysis of VOC removal processes in different aerobic vertical flow systems for groundwater remediation.  

UK PubMed Central (United Kingdom)

Vertical flow systems filled with porous medium have been shown to efficiently remove volatile organic contaminants (VOCs) from contaminated groundwater. To apply this semi-natural remediation strategy it is however necessary to distinguish between removal due to biodegradation and due to volatile losses to the atmosphere. Especially for (potentially) toxic VOCs, the latter needs to be minimized to limit atmospheric emissions. In this study, numerical simulation was used to investigate quantitatively the removal of volatile organic compounds in two pilot-scale water treatment systems: an unplanted vertical flow filter and a planted one, which could also be called a vertical flow constructed wetland, both used for the treatment of contaminated groundwater. These systems were intermittently loaded with contaminated water containing benzene and MTBE as main VOCs. The highly dynamic but permanently unsaturated conditions in the porous medium facilitated aerobic biodegradation but could lead to volatile emissions of the contaminants. Experimental data from porous material analyses, flow rate measurements, solute tracer and gas tracer test, as well as contaminant concentration measurements at the boundaries of the systems were used to constrain a numerical reactive transport modeling approach. Numerical simulations considered unsaturated water flow, transport of species in the aqueous and the gas phase as well as aerobic degradation processes, which made it possible to quantify the rates of biodegradation and volatile emissions and calculating their contribution to total contaminant removal. A range of degradation rates was determined using experimental results of both systems under two operation modes and validated by field data obtained at different operation modes applied to the filters. For both filters, simulations and experimental data point to high biodegradation rates, if the flow filters have had time to build up their removal capacity. For this case volatile emissions are negligible and total removal can be attributed to biodegradation, only. The simulation study thus supports the use of both of these vertical flow systems for the treatment of groundwater contaminated with VOCs and the use of reactive transport modeling for the assessment of VOCs removal and operation modes in these high performance treatment systems.

De Biase C; Carminati A; Oswald SE; Thullner M

2013-08-01

352

Logical diagrams in Serbian medieval manuscripts  

Directory of Open Access Journals (Sweden)

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

Žunji? Slobodan

2011-01-01

353

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

1991-01-01

354

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

Directory of Open Access Journals (Sweden)

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

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

2013-01-01

355

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

International Nuclear Information System (INIS)

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

2006-01-01

356

Sequential Voronoi diagram calculations using simple chemical reactions  

CERN Document Server

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

Costello, Ben de Lacy; Adamatzky, Andy

2012-01-01

357

Project Management Plan for the INEL technology logic diagrams  

International Nuclear Information System (INIS)

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

1992-01-01

358

Modeling Yin-Yang balance in Tai-chi diagram with a melting-freezing rotating device part 2 ---the similarity and characteristic of Tai-chi diagram  

Science.gov (United States)

The physical model describing the Yin-Yang balance in the Tai-chi diagram via the melting and freezing processes taking place in a rotating device presented in reference [1] is further developed. The system of equations formulating the melting and freezing processes is transformed to a dimensionless form. The advantage of dimensionless equations not only reduces a significant number of parameters involved in the problem but also provides physical insight of the Tai-chi diagram. The solution of dimensionless equations offers the similarity and characteristic of the Tai-chi diagram[1].

Lin, Sui; Chen, Tzu-Fang; Huo, Yuhua

2002-05-01

359

Phase diagrams of ferroelastic ditellurates  

International Nuclear Information System (INIS)

Formation peculiarities of domain structure of ferroelectric ditellurites are considered. To study the effect of different factors on the formation of the domain structure the phase diagram of solid solutions in systems CaxCd1-xTe2O5 and SrxCd1-xTe2O5, where x=0-1, has been investigated. In the studied crystals of the two systems a correlation between the formation of domain structure and the presence of real or hypothetic phase transition is observed

1989-01-01

360

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

Energy Technology Data Exchange (ETDEWEB)

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.

Friedsam, H.; Pushor, R.; Ruland, R.

1986-11-01

 
 
 
 
361

Simplifying the Scientific Writing and Review Process with SciFlow  

Directory of Open Access Journals (Sweden)

Full Text Available Scientific writing is an essential part of a student’s and researcher’s everyday life. In this paper we investigate the particularities of scientific writing and explore the features and limitations of existing tools for scientific writing. Deriving from this analysis and an online survey of the scientific writing processes of students and researchers at the University of Paderborn, we identify key principles to simplify scientific writing and reviewing. Finally, we introduce a novel approach to support scientific writing with a tool called SciFlow that builds on these principles and state of the art technologies like cloud computing.

Frederik Eichler; Wolfgang Reinhardt

2010-01-01

362

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

1993-01-01

363

On numerical simulation of flow, heat transfer and combustion processes in tangentially-fired furnace  

Energy Technology Data Exchange (ETDEWEB)

In this work, an Eulerian/Lagrangian approach has been employed to investigate numerically flow characteristics, heat transfer and combustion processes inside corner-fired power plant boiler furnace. To avoid pseudo-diffusion that is significant in modeling tangentially-fired furnaces, some attempts have been made at improving the finite-difference scheme. Comparisons have been made between standard {kappa}-{epsilon} model and RNG {kappa}-{epsilon} model. Some new developments on turbulent diffusion of particles are taken into account in an attempt to improve computational accuracy. Finally, temperature deviation is studied numerically so as to gain deeper insight into tangentially fired furnace.

Sun, P.; Fan, J.; Cen, K.

1999-07-01

364

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

Energy Technology Data Exchange (ETDEWEB)

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

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

1992-01-01

365

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

Energy Technology Data Exchange (ETDEWEB)

A digitally synchronized parallel pulse processing and data acquisition system for a flow cytometer has multiple parallel input channels with independent pulse digitization and FIFO storage buffer. A trigger circuit controls the pulse digitization on all channels. After an event has been stored in each FIFO, a bus controller moves the oldest entry from each FIFO buffer onto a common data bus. The trigger circuit generates an ID number for each FIFO entry, which is checked by an error detection circuit. The system has high speed and low error rate. 17 figs.

Engh, G.J. van den; Stokdijk, W.

1992-09-22

366

To the question of flowing processes interaction in the logistics of transport-freight complexes of enterprises  

Directory of Open Access Journals (Sweden)

Full Text Available In the article the questions of identification of structure and parameters of material flow and associate with it documentary and informative flows are considered and the principles of their co-operation, representing a basis for optimization of process of material traffic in the logistic transport-freight complexes of enterprises, are exposed.

Vladimir PARUNAKJAN; Ekaterina SIZOVA

2009-01-01

367

Test Case Generation Based on Use case and Sequence Diagram  

Directory of Open Access Journals (Sweden)

Full Text Available We present a comprehensive test case generation technique from UMLmodels. We use the features in UML 2.0 sequence diagram includingconditions, iterations, asynchronous messages and concurrent components.In our approach, test cases are derived from analysis artifacts such as usecases, their corresponding sequence diagrams and constraints specifiedacross all these artifacts. We construct Use case Dependency Graph (UDG)from use case diagram and Concurrent Control Flow Graph (CCFG) fromcorresponding sequence diagrams for test sequence generation. We focustesting on sequences of messages among objects of use case scenarios.Our testing strategy derives test cases using full predicate coverage criteria.Our proposed test case generation technique can be used for integration andsystem testing accommodating the object message and condition informationassociated with the use case scenarios. The test cases thus generated aresuitable for detecting synchronization and dependency of use cases andmessages, object interaction and operational faults. Finally, we have madean analysis and comparison of our approach with existing approaches, whichare based on other coverage criterion through an example.

Santosh Kumar Swain; Durga Prasad Mohapatra; Rajib Mall

2010-01-01

368

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

CERN Document Server

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

Sprittles, James

2012-01-01

369

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

International Nuclear Information System (INIS)

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

2001-01-01

370

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)

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.

Jean-Pierre Unger; Bruno Marchal; Sylvie Dugas; Marie-Jeanne Wuidar; Daniel Burdet; Pierre Leemans; Jacques Unger

2004-01-01

371

Potts models on Feynman diagrams  

International Nuclear Information System (INIS)

We investigate numerically and analytically Potts models on 'thin' random same concgeneric Feynman diagrams, using the idea that such models may be expressed as the N?1 limit of a matrix model. The thin random graphs in this limit are locally tree-like, in distinction to the 'fat' random graphs that appear in the planar Feynman diagram limit, N??, more familiar from discretized models of two-dimensional gravity. The interest of the thin graphs is that they give mean-field theory behaviour for spin models living on them without infinite range interactions or the boundary problems of genuine tree-like structures such as the Bethe lattice. q-state Potts models display a first-order transition in the mean field for q>2, so the thin-graph Potts models provide a useful test case for exploring discontinuous transitions in mean-field theories in which many quantities can be calculated explicitly in the saddle-point approximation. Such discontinuous transitions also appear in multiple Ising models on thin graphs and may have implications for the use of the replica trick in spin-glass models on random graphs. (author)

1997-11-07

372

Phase Diagrams for Sonoluminescing Bubbles  

CERN Multimedia

Sound driven gas bubbles in water can emit light pulses. This phenomenon is called sonoluminescence (SL). Two different phases of single bubble SL have been proposed: diffusively stable and diffusively unstable SL. We present phase diagrams in the gas concentration vs forcing pressure state space and also in the ambient radius vs gas concentration and vs forcing pressure state spaces. These phase diagrams are based on the thresholds for energy focusing in the bubble and two kinds of instabilities, namely (i) shape instabilities and (ii) diffusive instabilities. Stable SL only occurs in a tiny parameter window of large forcing pressure amplitude $P_a \\sim 1.2 - 1.5$atm and low gas concentration of less than $0.4\\%$ of the saturation. The upper concentration threshold becomes smaller with increasing forcing. Our results quantitatively agree with experimental results of Putterman's UCLA group on argon, but not on air. However, air bubbles and other gas mixtures can also successfully be treated in this approach i...

Hilgenfeldt, S; Brenner, M; Hilgenfeldt, Sascha; Lohse, Detlef; Brenner, Michael

1996-01-01

373

Kinetic modelling of aqueous atrazine ozonation processes in a continuous flow bubble contactor.  

UK PubMed Central (United Kingdom)

The ozonation of atrazine in different waters (ultrapure and surface waters) has been studied in continuous bubble contactors with kinetic modelling purposes. Three ozonation processes have been considered: ozonation alone and combined with hydrogen peroxide or UV radiation. The kinetic models are based on a molecular and free radical mechanism of reactions, reaction rate and mass transfer data and non-ideal flow analysis models for gas and water phases through the contactors (the tanks in series model and the dispersion model). The models predict well the experimental concentrations of atrazine, dissolved ozone and hydrogen peroxide both at non-steady state and steady state regimes. From both experimental and calculated results, atrazine conversions are observed to be highly dependent on the nature of water where ozonation is carried out. As far as removal of atrazine and oxidation intermediates are concerned, ozone combined with UV radiation resulted in the most effective ozonation process among the three studied.

Beltrán FJ; González M; Acedo B; Rivas FJ

2000-12-01

374

Evaluating the flow processes in ultrafine-grained materials at elevated temperatures  

Directory of Open Access Journals (Sweden)

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.

Megumi Kawasaki; Terence G. Langdon

2013-01-01

375

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

International Nuclear Information System (INIS)

A number of particle models that are suitable for simulating multiphase fluid flow and biogeological processes have been developed during the last few decades. Here we discuss three of them: (1) a microscopic model--molecular dynamics; (2) a mesoscopic model--dissipative particle dynamics; and (3) a macroscopic model--smoothed particle hydrodynamics. Particle methods are robust and versatile, and it is relatively easy to add additional physical, chemical and biological processes into particle codes. However, the computational efficiency of particle methods is low relative to continuum methods. Multiscale particle methods and hybrid (particle-particle and particle-continuum) methods are needed to improve computational efficiency and make effective use of emerging computational capabilities. These new methods are under development.

2007-01-01

376

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

Energy Technology Data Exchange (ETDEWEB)

A number of particle models that are suitable for simulating multiphase fluid flow and biogeological processes have been developed during the last few decades. Here we discuss three of them: a microscopic model - molecular dynamics; a mesoscopic model - dissipative particle dynamics; and a macroscopic model - smoothed particle hydrodynamics. Particle methods are robust and versatile, and it is relatively easy to add additional physical, chemical and biological processes into particle codes. However, the computational efficiency of particle methods is low relative to continuum methods. Multiscale particle methods and hybrid (particle–particle and particle–continuum) methods are needed to improve computational efficiency and make effective use of emerging computational capabilities. These new methods are under development.

Meakin, Paul; Tartakovsky, Alexandre M.; Scheibe, Timothy D.; Tartakovsky, Daniel M.; Redden, George; Long, Philip E.; Brooks, Scott C.; Xu, Zhijie

2007-08-01

377

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

Energy Technology Data Exchange (ETDEWEB)

A number of particle models that are suitable for simulating multiphase fluid flow and biogeological processes have been developed during the last few decades. Here we discuss three of them: a microscopic model - molecular dynamics; a mesoscopic model - dissipative particle dynamics; and a macroscopic model - smoothed particle hydrodynamics. Particle methods are robust and versatile, and it is relatively easy to add additional physical, chemical and biological processes into particle codes. However, the computational efficiency of particle methods is low relative to continuum methods. Multiscale particle methods and hybrid (particle–particle and particle–continuum) methods are needed to improve computational efficiency and make effective use of emerging computational capabilities. These new methods are under development.

Paul Meakin; Alexandre Tartakovsky; Tim Scheibe; Daniel Tartakovsky; Georgr Redden; Philip E. Long; Scott C. Brooks; Zhijie Xu

2007-06-01

378

Particle methods for simulation of subsurface multiphase fluid flow and biogeochemical processes  

Energy Technology Data Exchange (ETDEWEB)

A number of particle models that are suitable for simulating multiphase fluid flow and biogeochemical processes have been developed during the last few decades. Here we discuss three of them: a microscopic model - molecular dynamics; a mesoscopic model - dissipative particle dynamics; and a macroscopic model - smoothed particle hydrodynamics. Particle methods are robust and versatile, and it is relatively easy to add additional physical, chemical and biological processes into particle codes. However, the computational efficiency of particle methods is low relative to continuum methods. Multiscale particle methods and hybrid (particle-particle and particle-continuum) methods are needed to improve computational efficiency and make effective use of emerging computational capabilities. These new methods are under development.

Meakin, Paul [Idaho National Laboratory (United States); Tartakovsky, Alexandre [Pacific Northwest National Laboratory (United States); Scheibe, Tim [Pacific Northwest National Laboratory (United States); Tartakovsky, Daniel [University of California, San Diego (United States); Redden, George [Idaho National Laboratory (United States); Long, Philip E [Pacific Northwest National Laboratory (United States); Brooks, Scott C [Oak Ridge National Laboratory (United States); Xu Zhijie [Idaho National Laboratory (United States)

2007-07-15

379

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

International Nuclear Information System (INIS)

A number of particle models that are suitable for simulating multiphase fluid flow and biogeological processes have been developed during the last few decades. Here we discuss three of them: a microscopic model - molecular dynamics; a mesoscopic model - dissipative particle dynamics; and a macroscopic model - smoothed particle hydrodynamics. Particle methods are robust and versatile, and it is relatively easy to add additional physical, chemical and biological processes into particle codes. However, the computational efficiency of particle methods is low relative to continuum methods. Multiscale particle methods and hybrid (particle-particle and particle-continuum) methods are needed to improve computational efficiency and make effective use of emerging computational capabilities. These new methods are under development.

2007-01-01

380

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

Directory of Open Access Journals (Sweden)

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

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

2010-01-01

 
 
 
 
381

Summary of applications of TOUGH2 to the evaluation of multiphase flow processes at the WIPP  

International Nuclear Information System (INIS)

The Waste Isolation Pilot Plant (WIPP) is a US Department of Energy (DOE) research and development facility for the underground disposal of transuranic waste in southeastern New Mexico. The WIPP repository is located 655 m below the land surface in the lower portion of the Salado Formation, which is comprised of beds of pure and impure halite with thin interbeds of anhydrite and related clay seams. The regional dip of the Salado Formation is approximately 1 degree southeast in the vicinity of the repository. The proposed waste storage area has eight waste disposal panels, each of which will contain seven rooms. The repository is designed to follow a single stratigraphic horizon. Due to the dip, the north end of the repository will be about 10 meters higher than the south end. Waste that is emplaced in the disposal rooms will generate gas due to microbial degradation, anoxic corrosion, and radiolysis. Brine inflow to the rooms from the surrounding Salado Formation may significantly influence the gas generation rate and the total amount of gas generated. The salt surrounding the repository will creep in response to the excavation, reducing the room volume. Gas generation in the room may increase the pressure sufficiently to drive brine and gas into the surrounding Salado Formation. Migration of gas and brine in the Salado is an important factor in evaluating the performance of the repository. The studies summarized in this paper have. been performed to evaluate brine and gas flow processes in the WIPP disposal system and to identify some of the important processes. These studies are done in support of, but are not part of, the formal Performance Assessment (PA) effort. Because of probabilistic and system-scale requirements, the PA effort uses the Sandia-developed BRAGFLO (BRine And Gas FLOw) code for multiphase flow calculations

1995-01-01

382

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

Science.gov (United States)

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

Oguchi, Masahiro; Sakanakura, Hirofumi; Terazono, Atsushi

2012-08-24

383

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

UK PubMed Central (United Kingdom)

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.

Oguchi M; Sakanakura H; Terazono A

2013-10-01

384

Disentangling the functional consequences of the connectivity between optic-flow processing neurons.  

UK PubMed Central (United Kingdom)

Typically, neurons in sensory areas are highly interconnected. Coupling two neurons can synchronize their activity and affect a variety of single-cell properties, such as their stimulus tuning, firing rate or gain. All of these factors must be considered to understand how two neurons should be coupled to optimally process stimuli. We quantified the functional effect of an interaction between two optic-flow processing neurons (Vi and H1) in the fly (Lucilia sericata). Using a generative model, we estimated a uni-directional coupling from H1 to Vi. Especially at a low signal-to-noise ratio (SNR), the coupling strongly improved the information about optic-flow in Vi. We identified two constraints confining the strength of the interaction. First, for weak couplings, Vi benefited from inputs by H1 without a concomitant shift of its stimulus tuning. Second, at both low and high SNR, the coupling strength lay in a range in which the information carried by single spikes is optimal.

Weber F; Machens CK; Borst A

2012-03-01

385

Binocular integration of visual information: a model study on naturalistic optic flow processing.  

UK PubMed Central (United Kingdom)

The computation of visual information from both visual hemispheres is often of functional relevance when solving orientation and navigation tasks. The vCH-cell is a motion-sensitive wide-field neuron in the visual system of the blowfly Calliphora, a model system in the field of optic flow processing. The vCH-cell receives input from various other identified wide-field cells, the receptive fields of which are located in both the ipsilateral and the contralateral visual field. The relevance of this connectivity to the processing of naturalistic image sequences, with their peculiar dynamical characteristics, is still unresolved. To disentangle the contributions of the different input components to the cell's overall response, we used electrophysiologically determined responses of the vCH-cell and its various input elements to tune a model of the vCH-circuit. Their impact on the vCH-cell response could be distinguished by stimulating not only extended parts of the visual field of the fly, but also selected regions in the ipsi- and contralateral visual field with behaviorally generated optic flow. We show that a computational model of the vCH-circuit is able to account for the neuronal activities of the counterparts in the blowfly's visual system. Furthermore, we offer an insight into the dendritic integration of binocular visual input.

Hennig P; Kern R; Egelhaaf M

2011-01-01

386

A new algorithm for context-based biomedical diagram similarity estimation.  

UK PubMed Central (United Kingdom)

MOTIVATION: Diagrams embedded in the biomedical literature convey rich contents, which often concisely and intuitively highlight key thesis of a research article. Despite their vital importance and informative clues for biomedical literature navigation and retrieval; currently, we miss an effective computational method for automatically understanding and accessing these valuable resources. PROPOSED METHOD: To address the aforementioned gap, we propose a novel context-based algorithm for estimating the similarity between a pair of biomedical diagrams. The main difference of the proposed algorithm with respect to the existing methods lies in the new algorithm's incorporation of the semantic context associated with diagrams in their source documents into the diagram similarity estimation process. In addition, the new approach also performs a series of advanced image processing and text mining operations to comprehensively extract the semantic content graphically encoded inside diagram images. RESULTS: The new algorithm can be deployed as a reusable component providing a fundamental function for building many advanced, semantic-aware applications on biomedical diagram processing. As a case study, in our experiments, we demonstrate the advantage of the new algorithm for diagram retrieval. A set of biomedical diagram search and ranking experiments were conducted, where the performance of the new method was compared with that of five peer methods. The comparison results demonstrate the performance superiority of the new algorithm with all peer methods with statistical significance.

Xu S; Sheng J; Luo X

2013-03-01

387

Leak before break piping evaluation diagram  

International Nuclear Information System (INIS)

[en] Traditionally Leak Before Break (LBB) has been applied to the evaluation of piping in existing nuclear plants. This paper presents a simple method for evaluating piping systems for LBB during the design process. This method produces a piping evaluation diagram (PED) which defines the LBB requirements to the piping designer for use during the design process. Several sets of LBB analyses are performed for each different pipe size and material considered in the LBB application. The results of this method are independent of the actual pipe routing. Two complete LBB evaluations are performed to determine the maximum allowable stability load, one evaluation for a low normal operating load, and the other evaluation for a high normal operating load. These normal operating loads span the typical loads for the particular system being evaluated. In developing the allowable loads, the appropriate LBB margins are included in the PED preparation. The resulting LBB solutions are plotted as a set of allowable curves for the maximum design basis load, such is the seismic load versus the normal operating load. Since the required margins are already accounted for in the LBB PED, the piping designer can use the diagram directly with the results of the piping analysis and determine immediately if the current piping arrangement passes LBB. Since the LBB PED is independent of pipe routing, changes to the piping system can be evaluated using the existing PED. For a particular application, all that remains is to confirm that the actual materials and pipe sizes assumed in creating the particular design are built into the plant

1994-01-01

388

Phase diagrams for high Tc superconductors  

International Nuclear Information System (INIS)

The phase diagrams of ternary and quaternary systems containing superconducting phases are presented, as are the phase diagrams of the associated binary systems. The diagrams are divided into two large groups: (1) alkaline earth-rare earth-copper-oxygen diagrams, and (2) alkaline earth-bismuth/lead-copper-oxygen diagrams. The first group includes BaO-REO-CuO systems followed by SrO-REO-CuO or Nd2O3-CeO-CuO systems. The second group includes systems related to the AE-Bi2O3-CuO and AE-PbO-CuO systems. The phase diagrams are accompanied by notes relating procedures used in the studies, results obtained, and comparisons with the results in the literature for the same system.

1991-01-01

389

Use of the GranuFlow Process in Coal Preparation Plants to Improve Energy Recovery and Reduce Coal Processing Wastes  

Energy Technology Data Exchange (ETDEWEB)

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.

Glenn A. Shirey; David J. Akers

2005-12-31

390

On-line graph processing study on phase separation of two-phase flow in T-junction  

International Nuclear Information System (INIS)

By use of the on-line graph processing measure system, an experimental study of phase separation of air-water stratified, bubbly and slug flow in the horizontal T-junction is carried out. For the first time, 'the new type of complete phase separation' is found and defined by the visual experiment, which shows that the air flow entering the T junction will flow into the run outlet completely under certain conditions. Also, 'the pressure wave feed back effect' and 'the branch gas flow reorganization effect' are found and analyzed. The complexity of this phase separation phenomenon in the T-junction has been further revealed via the on-line graph processing technology. Meanwhile, the influences of the inlet mass flow rate W1, the inlet mass quality X-1, and the mass extraction rate W3/W1 on phase separation are analyzed.

1997-01-01

391

Some interesting color-magnitude diagrams  

Science.gov (United States)

Some CCD color-magnitude diagrams for a few open clusters, global clusters, and dwarf spheroidal galaxies in the Local Group are presented. Consideration is given to the open clusters NGC 7789, NGC 2818, NGC 6205, and NGC 6341, the spheroidal galaxy in Draco, the B, R color-magnitude diagram of Carina, and the B, R color-magnitude diagram for the dwarf spheroidal galaxy in Fornax.

Stetson, Peter B.

1997-07-01

392

Number and weights of Feynman diagrams  

International Nuclear Information System (INIS)

The functional techniques of field theory are adapted to the problem of evaluating sums of combinatoric and group-theoretic weights of Feynman diagrams in phi/sup N/, quantum electrodynamics and non-Abelian theories. Considered are various classes of diagrams such as connected, one-particle-irreducible, and skeleton diagrams. For finite orders exact sume are given by compact recursion formulas. For higher orders estimates are obtained from the exact results or by steepest-descent methods.

1978-01-01

393

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

DEFF Research Database (Denmark)

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

Duijm, Nijs Jan; Markert, Frank

2009-01-01

394

Effect of pressure transducer position on measured cylinder pressure diagram of high speed diesel engines  

Energy Technology Data Exchange (ETDEWEB)

The cylinder pressure diagram is a valuable source of information for reciprocating internal combustion engines. If processed, it provides information concerning the combustion process inside the engine cylinder. During this process, a problem that usually arises is the proper mounting of the pressure sensor on the cylinder head. The optimum is to flush-mount the transducer to the cylinder head so that it can be directly in contact with the gas. Unfortunately, in many cases, and mainly in small size, high speed commercial engines, this is not always possible. For this reason, the engineer must position the transducer in a location away from the cylinder head to bring it to continuous contact with the cylinder gas through a duct. From experiments, we find that this may result in errors in the measured values of the gas pressure that differ from the actual ones inside the combustion chamber. In the case of spark ignition engines, we face this problem by using pressure sensors mounted on the engine spark plug, but in the case of Diesel engines, we must mount the transducer separately. The main scope of the present work is to examine the effect of the transducer position on the measured pressure diagram in high speed diesel engines. For this purpose, in the present work, a theoretical investigation is conducted using a simulation model developed by the authors, where the unsteady flow problem in the connecting pipeline from the combustion chamber to the transducer is solved using a finite difference scheme. A simple combustion model is used to simulate the operation of a high speed diesel engine at various conditions. The theoretical investigation involves the study of the effect of the connecting pipe geometry (diameter and length) and engine speed and load on the measured pressure diagram and on the parameters derived from it. From this investigation, important results are obtained that enable us to determine the magnitude of the error in pressure management that results from the positioning of the transducer away from the combustion chamber. The results reveal the limits within which the pressure measurements are reliable and may be possibly used to develop a method for correcting the measured pressure diagram. (Author)

Hountalas, D.T.; Anestis, A. [National Technical Univ. of Athens, Thermal Engineering Section, Athens (Greece)

1998-12-31

395

Solving Hybrid Influence Diagrams with Deterministic Variables  

CERN Multimedia

We describe a framework and an algorithm for solving hybrid influence diagrams with discrete, continuous, and deterministic chance variables, and discrete and continuous decision variables. A continuous chance variable in an influence diagram is said to be deterministic if its conditional distributions have zero variances. The solution algorithm is an extension of Shenoy's fusion algorithm for discrete influence diagrams. We describe an extended Shenoy-Shafer architecture for propagation of discrete, continuous, and utility potentials in hybrid influence diagrams that include deterministic chance variables. The algorithm and framework are illustrated by solving two small examples.

Li, Yijing

2012-01-01

396

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

Energy Technology Data Exchange (ETDEWEB)

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).

Solomon, N.; Solomon, I.

2010-07-01

397

Non-invasive flow cytometric monitoring of pHi in cell culture processes using EGFP.  

UK PubMed Central (United Kingdom)

We have described a new method for monitoring of cell culture processes using green fluorescent protein (GFP) fluorescent intensity. GFP has been used as a non-invasive fluorescent reporter for various cellular processes. In this study, enhanced (EGFP) was found to be a very sensitive indicator of pHi in in vitro cell culture, and responded rapidly to extracellular pH (pHe) changes. EGFP transfected cells were evaluated for pHi changes by flow cytometry, by measuring EGFP fluorescent intensity, and compared to that of the pH-sensitive fluoroprobe, SNARF. EGFP intensity was found to reflect pHi values of cells at different pHe in the presence of nigericin and was affected by the addition of HCl and NaOH. Significant changes in pHi were detected at different stages of batch culture and when using different cell density and media composition. The EGFP assay can be used to minimise the perturbation of cells and processes under study, thus leading to accurate information about the physiological state of single cells in a population. The results establish the application of EGFP as a non-invasive indicator of pHi for monitoring of mammalian cell culture processes.

Naciri M; Al-Rubeai M

2006-08-01

398

Non-invasive flow cytometric monitoring of pHi in cell culture processes using EGFP.  

Science.gov (United States)

We have described a new method for monitoring of cell culture processes using green fluorescent protein (GFP) fluorescent intensity. GFP has been used as a non-invasive fluorescent reporter for various cellular processes. In this study, enhanced (EGFP) was found to be a very sensitive indicator of pHi in in vitro cell culture, and responded rapidly to extracellular pH (pHe) changes. EGFP transfected cells were evaluated for pHi changes by flow cytometry, by measuring EGFP fluorescent intensity, and compared to that of the pH-sensitive fluoroprobe, SNARF. EGFP intensity was found to reflect pHi values of cells at different pHe in the presence of nigericin and was affected by the addition of HCl and NaOH. Significant changes in pHi were detected at different stages of batch culture and when using different cell density and media composition. The EGFP assay can be used to minimise the perturbation of cells and processes under study, thus leading to accurate information about the physiological state of single cells in a population. The results establish the application of EGFP as a non-invasive indicator of pHi for monitoring of mammalian cell culture processes. PMID:16963074

Naciri, Mariam; Al-Rubeai, Mohamed

2006-08-28

399

Hubble's diagram and cosmic expansion.  

UK PubMed Central (United Kingdom)

Edwin Hubble's classic article on the expanding universe appeared in PNAS in 1929 [Hubble, E. P. (1929) Proc. Natl. Acad. Sci. USA 15, 168-173]. The chief result, that a galaxy's distance is proportional to its redshift, is so well known and so deeply embedded into the language of astronomy through the Hubble diagram, the Hubble constant, Hubble's Law, and the Hubble time, that the article itself is rarely referenced. Even though Hubble's distances have a large systematic error, Hubble's velocities come chiefly from Vesto Melvin Slipher, and the interpretation in terms of the de Sitter effect is out of the mainstream of modern cosmology, this article opened the way to investigation of the expanding, evolving, and accelerating universe that engages today's burgeoning field of cosmology.

Kirshner RP

2004-01-01

400

Comparative Study on DFD to UML Diagrams Transformations  

CERN Multimedia

Most of legacy systems use nowadays were modeled and documented using structured approach. Expansion of these systems in terms of functionality and maintainability requires shift towards object-oriented documentation and design, which has been widely accepted by the industry. In this paper, we present a survey of the existing Data Flow Diagram (DFD) to Unified Modeling language (UML) transformation techniques. We analyze transformation techniques using a set of parameters, identified in the survey. Based on identified parameters, we present an analysis matrix, which describes the strengths and weaknesses of transformation techniques. It is observed that most of the transformation approaches are rule based, which are incomplete and defined at abstract level that does not cover in depth transformation and automation issues. Transformation approaches are data centric, which focuses on data-store for class diagram generation. Very few of the transformation techniques have been applied on case study as a proof of ...

Jilani, Atif A A; Nadeem, Aamer

2011-01-01

 
 
 
 
401

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.

2003-04-02

402

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

Energy Technology Data Exchange (ETDEWEB)

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.

Wu, Yu-Shu; Liu, H.H.; Bodvarsson, G.S.

2002-12-05

403

The efficiency of turn-over processes in degraded peat as investigated under continuous flow conditions  

Science.gov (United States)

Nitrate removal from run-off from agricultural land is in general required to reach a "good chemical status" of surface and groundwater bodies according to the European Water Framework Directive. Removing nitrates via heterotrophic denitrification is highly effective but requires stable anoxic environmental conditions as well as available organic carbon as an electron donator. Constructed wetlands, established on peat soils, through which the nitrate-loaded water is routed, may provide denitrification favorable conditions. A long-term flow experiment (mesocosm) was conducted employing a laboratory container set-up filled with decomposed peat aiming at quantifying the nitrate removal efficiency at various nitrate influx rates. The redox potential was measured at different depths to determine the spatial distribution of denitrificating zones. This new methodological approach allows the observation of biological nitrate turn over without interrupting the adjusted flow rate. We investigated the hydraulic properties and derived transport parameters for the mesocosm by analyzing experimental data from tracer tests. The obtained bromide breakthrough curves (BTC) were subjected to model analysis using the CXTFIT routine of the STANMOD software package. It could be demonstrated that the degraded peat has a dual porosity structure with roughly 40% of the pore water not participating in convective flow and transport processes. Further, the first flushing of mineralized nitrate upon rewetting and onset of flux may compromise any positive clean-up and nitrate removal effects occurring during long-term operation of peat wetlands. The development of the spatial sequence of bacterial cultures is characterized by the redox potential. It is dominated by the available substrates that serve as electron acceptors in bacterial respiration and occurs in a thermodynamically determined top-down order. The zonal development of the nitrate-consuming bacteria was observed and used to describe the removal efficiency of the mesocosm.

Kleimeier, Christian; Karsten, Ulf; Janssen, Manon; Lennartz, Bernd

2013-04-01

404

Combining LCT tools for the optimization of an industrial process: material and energy flow analysis and best available techniques.  

UK PubMed Central (United Kingdom)

Life cycle thinking (LCT) is one of the philosophies that has recently appeared in the context of the sustainable development. Some of the already existing tools and methods, as well as some of the recently emerged ones, which seek to understand, interpret and design the life of a product, can be included into the scope of the LCT philosophy. That is the case of the material and energy flow analysis (MEFA), a tool derived from the industrial metabolism definition. This paper proposes a methodology combining MEFA with another technique derived from sustainable development which also fits the LCT philosophy, the BAT (best available techniques) analysis. This methodology, applied to an industrial process, seeks to identify the so-called improvable flows by MEFA, so that the appropriate candidate BAT can be selected by BAT analysis. Material and energy inputs, outputs and internal flows are quantified, and sustainable solutions are provided on the basis of industrial metabolism. The methodology has been applied to an exemplary roof tile manufacture plant for validation. 14 Improvable flows have been identified and 7 candidate BAT have been proposed aiming to reduce these flows. The proposed methodology provides a way to detect improvable material or energy flows in a process and selects the most sustainable options to enhance them. Solutions are proposed for the detected improvable flows, taking into account their effectiveness on improving such flows.

Rodríguez MT; Andrade LC; Bugallo PM; Long JJ

2011-09-01

405

Combining LCT tools for the optimization of an industrial process: material and energy flow analysis and best available techniques.  

Science.gov (United States)

Life cycle thinking (LCT) is one of the philosophies that has recently appeared in the context of the sustainable development. Some of the already existing tools and methods, as well as some of the recently emerged ones, which seek to understand, interpret and design the life of a product, can be included into the scope of the LCT philosophy. That is the case of the material and energy flow analysis (MEFA), a tool derived from the industrial metabolism definition. This paper proposes a methodology combining MEFA with another technique derived from sustainable development which also fits the LCT philosophy, the BAT (best available techniques) analysis. This methodology, applied to an industrial process, seeks to identify the so-called improvable flows by MEFA, so that the appropriate candidate BAT can be selected by BAT analysis. Material and energy inputs, outputs and internal flows are quantified, and sustainable solutions are provided on the basis of industrial metabolism. The methodology has been applied to an exemplary roof tile manufacture plant for validation. 14 Improvable flows have been identified and 7 candidate BAT have been proposed aiming to reduce these flows. The proposed methodology provides a way to detect improvable material or energy flows in a process and selects the most sustainable options to enhance them. Solutions are proposed for the detected improvable flows, taking into account their effectiveness on improving such flows. PMID:21802848

Rodríguez, M T Torres; Andrade, L Cristóbal; Bugallo, P M Bello; Long, J J Casares

2011-07-08

406

Train traffic scheduling method considering passengers flowing model based on object-oriented model; Object shiko ni motozuku jokyakuryu wo koryoshita ressha dia sakusei shuho  

Energy Technology Data Exchange (ETDEWEB)

In this paper, we propose a new scheduling and operating method for railway systems based on passengers flowing model. The method is constructed by two level, a higher level named by the scheduling level and a lower level named by the operating level. In the scheduling level, several important diagram factors that include the type of train, stop stations and stop time, and a desire dial performance which include fast achievement, lower congestion will be determined by veteran operators. In the operating level, based on those important diagram factors determined from higher level, the detail train diagram is made both by train traffic simulations and passengers flowing simulations using object-oriented technique. The results obtained from the operating level will be feedback to the higher level in order to modify some key diagram factors, and then the lower level will do again, this interactive process will be continued until a desire performance could be obtained. 11 refs., 11 figs., 3 tabs.

Harada, M. [Oki Electric Industry Co. Ltd., Tokyo (Japan); Gao, H.; Abe, K. [Tohoku University, Sendai (Japan); Abe, K. [Mitsubishi Electric Corp., Tokyo (Japan); Nakao, K. [Osaka Institute of Technology, Osaka (Japan)

1998-02-01

407

Velocity field measurement of flow inside SNOUT of zine plating process using single-frame PIV technique  

Energy Technology Data Exchange (ETDEWEB)

In the zinc-plating process of steel strips, the snout has been installed at the entering region of the galvanized strip into the molten Zinc pot. In order to solve imperfections on the galvanized steel strip surface., a precise quantitative analysis on the flow inside the snout, both on the deoxidisation gas flow above the free surface and the molten zinc flow below the surface is needed. A 1/10 scale water model of the Zn plating process including the snout and an endless belt strip was made. PIV(Particle Image Velocimetry) velocity field measurements were carried out inside the snout at the strip speed V{sub s}=1.5 m/s. Aluminum powder particles (1{mu}m) and atomized olive oil (3{mu}m) were used as seeding particles to simulate the molten Zinc flow and deoxidisation gas flow, respectively. A pulsed Nd:Yag laser and a 2 K x 2 K high-resolution CCD camera were synchronized for the PIV velocity field measurement. The deoxidisation gas flow in front of the strip inside the snout can be characterized by a large-scale vortex rotating clockwise direction formed by the moving strip. In the rear side of the strip, a counter-clockwise vortex is formed and some of the flow entrained by the moving strip impinges on the free surface of molten zinc. The liquid flow in front of the strip is governed by the flow entering the snout, caused by the spinning sink roll. Just below the free surface a counter-clockwise vortex is formed near the snout wall. The moving strip affects dominantly the flow behind the strip inside the snout, and large amounts of the liquid flow follow the moving strip toward the sink roll. The thickness of the flow following the strip is very thin in the front side due to the uprising flow, however thick boundary layer is fo