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Sample records for process flow diagram

  1. TEP process flow diagram

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-01-01

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

  2. Modeling process flow using diagrams

    NARCIS (Netherlands)

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

    2010-01-01

    In the practice of process improvement, tools such as the flowchart, the value-stream map (VSM), and a variety of ad hoc variants of such diagrams are commonly used. The purpose of this paper is to present a clear, precise, and consistent framework for the use of such flow diagrams in process improv

  3. Analysis of Optimal Process Flow Diagrams of Light Naphtha Isomerization Process by Mathematic Modelling Method

    Directory of Open Access Journals (Sweden)

    Chuzlov Vjacheslav

    2016-01-01

    Full Text Available An approach to simulation of hydrocarbons refining processes catalytic reactors. The kinetic and thermodynamic research of light naphtha isomerization process was conducted. The kinetic parameters of hydrocarbon feedstock chemical conversion on different types of platinum-content catalysts was established. The estimation of efficiency of including different types of isomerization technologies in oil refinery flow diagram was performed.

  4. Business Process Flow Diagrams in Tissue Bank Informatics System Design, and Identification and Communication of Best Practices: The Pharmaceutical Industry Experience.

    Science.gov (United States)

    McDonald, Sandra A; Velasco, Elizabeth; Ilasi, Nicholas T

    2010-12-01

    Pfizer, Inc.'s Tissue Bank, in conjunction with Pfizer's BioBank (biofluid repository), endeavored to create an overarching internal software package to cover all general functions of both research facilities, including sample receipt, reconciliation, processing, storage, and ordering. Business process flow diagrams were developed by the Tissue Bank and Informatics teams as a way of characterizing best practices both within the Bank and in its interactions with key internal and external stakeholders. Besides serving as a first step for the software development, such formalized process maps greatly assisted the identification and communication of best practices and the optimization of current procedures. The diagrams shared here could assist other biospecimen research repositories (both pharmaceutical and other settings) for comparative purposes or as a guide to successful informatics design. Therefore, it is recommended that biorepositories consider establishing formalized business process flow diagrams for their laboratories, to address these objectives of communication and strategy.

  5. Functionality Semantics of Predicate Data Flow Diagram

    Institute of Scientific and Technical Information of China (English)

    高晓雷; 缪淮扣; 刘玲

    2004-01-01

    SOZL (structured methodology + object-oriented methodology + Z language) is a language that attempts to integrate structured method, object-oriented method and formal method. The core of this language is predicate data flow diagram (PDFD). In order to eliminate the ambiguity of predicate data flow diagrams and their associated textual specifications, a formalization of the syntax and semantics of predicate data flow diagrams is necessary. In this paper we use Z notation to define an abstract syntax and the related structural constraints for the PDFD notation, and provide it with an axiomatic semantics based on the concept of data availability and functionality of predicate operation. Finally, an example is given to establish functionality consistent decomposition on hierarchical PDFD (HPDFD).

  6. Comprehending process diagrams in biology education

    NARCIS (Netherlands)

    Kragten, M.

    2015-01-01

    Students in secondary Science education seem to have difficulties with comprehending diagrams. Process diagrams are an important type of representation in Biology for explaining processes like protein synthesis, compound cycles, etc. In this thesis, we aimed at getting deeper insight into students’

  7. Making Data Flow Diagrams Accessible for Visually Impaired Students Using Excel Tables

    Science.gov (United States)

    Sauter, Vicki L.

    2015-01-01

    This paper addresses the use of Excel tables to convey information to blind students that would otherwise be presented using graphical tools, such as Data Flow Diagrams. These tables can supplement diagrams in the classroom when introducing their use to understand the scope of a system and its main sub-processes, on exams when answering questions…

  8. Stock flow diagram analysis on solid waste management in Malaysia

    Science.gov (United States)

    Zulkipli, Faridah; Nopiah, Zulkifli Mohd; Basri, Noor Ezlin Ahmad; Kie, Cheng Jack

    2016-10-01

    The effectiveness on solid waste management is a major importance to societies. Numerous generation of solid waste from our daily activities has risked for our communities. These due to rapid population grow and advance in economic development. Moreover, the complexity of solid waste management is inherently involved large scale, diverse and element of uncertainties that must assist stakeholders with deviating objectives. In this paper, we proposed a system dynamics simulation by developing a stock flow diagram to illustrate the solid waste generation process and waste recycle process. The analysis highlights the impact on increasing the number of population toward the amount of solid waste generated and the amount of recycled waste. The results show an increment in the number of population as well as the amount of recycled waste will decrease the amount of waste generated. It is positively represent the achievement of government aim to minimize the amount of waste to be disposed by year 2020.

  9. Introducing the Circular Flow Diagram to Business Students

    Science.gov (United States)

    Daraban, Bogdan

    2010-01-01

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

  10. The fundamental diagram : a macroscopic traffic flow model.

    NARCIS (Netherlands)

    Botma, H.

    1976-01-01

    In models of traffic flow, the interactions between vehicles are of prime interest, and are based on characteristics of the drivers, road and vehicles. The fundamental diagram is a representation of a relationship on a macroscopic level in the steady state between the quantity of traffic and a chara

  11. The non-equilibrium phase diagrams of flow-induced crystallization and melting of polyethylene.

    Science.gov (United States)

    Wang, Zhen; Ju, Jianzhu; Yang, Junsheng; Ma, Zhe; Liu, Dong; Cui, Kunpeng; Yang, Haoran; Chang, Jiarui; Huang, Ningdong; Li, Liangbin

    2016-09-09

    Combining extensional rheology with in-situ synchrotron ultrafast x-ray scattering, we studied flow-induced phase behaviors of polyethylene (PE) in a wide temperature range up to 240 °C. Non-equilibrium phase diagrams of crystallization and melting under flow conditions are constructed in stress-temperature space, composing of melt, non-crystalline δ, hexagonal and orthorhombic phases. The non-crystalline δ phase is demonstrated to be either a metastable transient pre-order for crystallization or a thermodynamically stable phase. Based on the non-equilibrium phase diagrams, nearly all observations in flow-induced crystallization (FIC) of PE can be well understood. The interplay of thermodynamic stabilities and kinetic competitions of the four phases creates rich kinetic pathways for FIC and diverse final structures. The non-equilibrium flow phase diagrams provide a detailed roadmap for precisely processing of PE with designed structures and properties.

  12. Evaluation of the Synthoil process. Volume III. Unit block flow diagrams for a 100,000 barrel/stream day facility

    Energy Technology Data Exchange (ETDEWEB)

    Salmon, R.; Edwards, M.S.; Ulrich, W.C.

    1977-06-01

    This volume consists of individual block flowsheets for the various units of the Synthoil facility, showing the overall flows into and out of each unit. Material balances for the following units are incomplete because these are proprietary processes and the information was not provided by the respective vendors: Unit 24-Claus Sulfur Plant; Unit 25-Oxygen Plant; Unit 27-Sulfur Plant (Redox Type); and Unit 28-Sour Water Stripper and Ammonia Recovery Plant. The process information in this form was specifically requested by ERDA/FE for inclusion in the final report.

  13. Effect of speed matching on fundamental diagram of pedestrian flow

    Science.gov (United States)

    Fu, Zhijian; Luo, Lin; Yang, Yue; Zhuang, Yifan; Zhang, Peitong; Yang, Lizhong; Yang, Hongtai; Ma, Jian; Zhu, Kongjin; Li, Yanlai

    2016-09-01

    Properties of pedestrian may change along their moving path, for example, as a result of fatigue or injury, which has never been properly investigated in the past research. The paper attempts to study the speed matching effect (a pedestrian adjusts his velocity constantly to the average velocity of his neighbors) and its influence on the density-velocity relationship (a pedestrian adjust his velocity to the surrounding density), known as the fundamental diagram of the pedestrian flow. By the means of the cellular automaton, the simulation results fit well with the empirical data, indicating the great advance of the discrete model for pedestrian dynamics. The results suggest that the system velocity and flow rate increase obviously under a big noise, i.e., a diverse composition of pedestrian crowd, especially in the region of middle or high density. Because of the temporary effect, the speed matching has little influence on the fundamental diagram. Along the entire density, the relationship between the step length and the average pedestrian velocity is a piecewise function combined two linear functions. The number of conflicts reaches the maximum with the pedestrian density of 2.5 m-2, while decreases by 5.1% with the speed matching.

  14. Microsoft Visio 2013 business process diagramming and validation

    CERN Document Server

    Parker, David

    2013-01-01

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

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

    Science.gov (United States)

    Luzzatto-Fegiz, Paolo

    2011-11-01

    Steady fluid solutions play a special role in the dynamics of a flow: stable states may be realized in practice, while unstable ones may act as attractors. Unfortunately, determining stability is often a process far more laborious than finding steady states; indeed, even for simple vortex or wave flows, stability properties have often been the subject of debate. We consider here a stability idea originating with Lord Kelvin (1876), which involves using the second variation of the energy, δ2 E , to establish bounds on a perturbation. However, for numerically obtained flows, computing δ2 E explicitly is often not feasible. To circumvent this issue, Saffman & Szeto (1980) proposed an argument linking changes in δ2 E to turning points in a bifurcation diagram, for families of steady flows. Later work has shown that this argument is unreliable; the two key issues are associated with the absence of a formal turning-point theory, and with the inability to detect bifurcations (Dritschel 1995, and references therein). In this work, we build on ideas from bifurcation theory, and link turning points in a velocity-impulse diagram to changes in δ2 E ; in addition, this diagram delivers the direction of the change of δ2 E , thereby providing information as to whether stability is gained or lost. To detect hidden solution branches, we introduce to these fluid problems concepts from imperfection theory. The resulting approach, involving ``imperfect velocity-impulse'' diagrams, leads us to new and surprising results for a wide range of fundamental vortex and wave flows; we mention here the calculation of the first steady vortices without any symmetry, and the uncovering of the complete solution structure for vortex pairs. In addition, we find precise agreement with available results from linear stability analysis. Doctoral work advised by C.H.K. Williamson at Cornell University.

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

    Science.gov (United States)

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

    2013-06-01

    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 ε and δ 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.

  17. Phase Stability Diagrams for High Temperature Corrosion Processes

    Directory of Open Access Journals (Sweden)

    J. J. Ramos-Hernandez

    2013-01-01

    Full Text Available Corrosion phenomena of metals by fused salts depend on chemical composition of the melt and environmental conditions of the system. Detail knowledge of chemistry and thermodynamic of aggressive species formed during the corrosion process is essential for a better understanding of materials degradation exposed to high temperature. When there is a lack of kinetic data for the corrosion processes, an alternative to understand the thermodynamic behavior of chemical species is to utilize phase stability diagrams. Nowadays, there are several specialized software programs to calculate phase stability diagrams. These programs are based on thermodynamics of chemical reactions. Using a thermodynamic data base allows the calculation of different types of phase diagrams. However, sometimes it is difficult to have access to such data bases. In this work, an alternative way to calculate phase stability diagrams is presented. The work is exemplified in the Na-V-S-O and Al-Na-V-S-O systems. This system was chosen because vanadium salts is one of the more aggressive system for all engineering alloys, especially in those processes where fossil fuels are used.

  18. Improving The Decisional Process By Using UML Diagrams

    Directory of Open Access Journals (Sweden)

    Udrica Mioara

    2012-06-01

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

  19. Phase diagrams properties of the mixed traffic flow on a crossroad

    Science.gov (United States)

    Li, Qi-Lang; Wang, Bing-Hong; Liu, Mu-Ren

    2010-11-01

    Based on the Ishibashi and Fukui crossroad traffic flow model [Y. Ishibashi and M. Fukui. J. Phys. Soc. Japan. 70 (2001) 2793], mixed traffic flow (i.e., the fast and slow vehicles with different maximum velocities are mixed) is investigated in this work. According to the numerical simulation results and the principle for constructing the phase diagram, phase diagrams for mixed traffic flow are constructed. It is noted that the topology of these phase diagrams is similar to that of phase diagrams for homogeneous vehicles (which refers to slow vehicles only). From the phase diagrams, it is evident that mixed traffic flow is influenced by the mixing rate f (fraction of slow and fast vehicles) in regions II and V, but not in other regions. Although a mixture of fast and slow vehicles is introduced in the crossroad traffic flow model, the separation between phases in the phase diagrams remains linear. For a given q (the vehicle density on the northbound road), one flow plateau appears in regions IIx or IVy, while two maximum flow plateaus appear in region V in each of the phase diagrams. The maximum flow values in region V reflect the maximum traffic capacity for the traffic system as defined in this work. Since mixed traffic flow is a common phenomenon in real traffic, this work may offer help in real traffic simulations and traffic management.

  20. What can we learn by comparing students' diagram-construction processes with the mathematical conceptions inferred from their explanations with completed diagrams?

    Science.gov (United States)

    Lobato, Joanne; Hohensee, Charles; Diamond, Jaime Marie

    2014-09-01

    Despite recent research interest in student-created diagrams, little research has systematically investigated students' diagram- construction processes, meaning the order and manner in which students create markings as they physically generate diagrams. In this study, we characterize the various processes students use to create diagrams that represent a quadratic motion situation involving increasing speed, and we explore how these diagram-construction processes are related to students' conceptions of speed as inferred from their explanations with their completed diagrams. Previous literature suggests contrasting predictions regarding whether or not students' diagram-construction processes are closely related (from our perspective as researchers) to students' inferred conceptions. We see the study as having value for research and practice by raising new questions related to diagram-construction processes, pointing to the potential formative assessment value of attending to diagram-construction processes, and demonstrating the need for the development of theory to explain the relationships identified by this study.

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

    Science.gov (United States)

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

    1991-01-01

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

  2. Query Processing for Probabilistic State Diagrams Describing Multiple Robot Navigation in an Indoor Environment

    Energy Technology Data Exchange (ETDEWEB)

    Czejdo, Bogdan [ORNL; Bhattacharya, Sambit [North Carolina Fayetteville State University; Ferragut, Erik M [ORNL

    2012-01-01

    This paper describes the syntax and semantics of multi-level state diagrams to support probabilistic behavior of cooperating robots. The techniques are presented to analyze these diagrams by querying combined robots behaviors. It is shown how to use state abstraction and transition abstraction to create, verify and process large probabilistic state diagrams.

  3. Fundamental diagram in traffic flow of mixed vehicles on multi-lane highway

    Science.gov (United States)

    Tanaka, Katsunori; Nagatani, Takashi; Masukura, Shuichi

    2008-09-01

    We study the fundamental diagram for traffic flow of vehicular mixture on a multi-lane highway. We present the car-following model of multi-lane traffic in which slow and fast vehicles flow with changing lanes. We investigate the traffic states of the vehicular mixture under the periodic boundary. Two values of the current appear at a density and two current curves are obtained. Vehicles move with changing lanes in the traffic state of high current, while vehicles move without changing lanes in the traffic state of low current. They depend on the density, the fraction of slow vehicles, and the initial condition. In the high-current curve, the jamming transition between the free flow and the jammed state occurs at a low density. The fundamental diagrams (current-density diagrams) are shown for the single-lane, two-lane, three-lane, and four-lane traffics.

  4. Applying state diagrams to food processing and development

    Science.gov (United States)

    Roos, Y.; Karel, M.

    1991-01-01

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

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

    Science.gov (United States)

    Kragten, Marco; Admiraal, Wilfried; Rijlaarsdam, Gert

    2015-01-01

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

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

    Science.gov (United States)

    Kragten, Marco; Admiraal, Wilfried; Rijlaarsdam, Gert

    2015-01-01

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

  7. Creating Royal Australian Navy Standard Operating Procedures using Flow Diagrams

    Science.gov (United States)

    2015-08-01

    DST-Group-TR-3137 UNCLASSIFIED Acronyms 4TQ 4TQ Toolkit ABR Australian Book of Reference ADF Australian Defence Force BPMN Business...steps to perform the activity. Object Management Group’s (OMG) Business Process Model and Notation ( BPMN ) [10] is becoming the standard to use when...Department of Defence 10. Object Management Group, Business Process Model and Notation ( BPMN ), version 2.0. 2011, Object Management Group: http

  8. Multivalued fundamental diagrams of traffic flow in the kinetic Fokker-Planck limit

    CERN Document Server

    Visconti, Giuseppe; Puppo, Gabriella; Tosin, Andrea

    2016-01-01

    Starting from interaction rules based on two levels of stochasticity we study the influence of the microscopic dynamics on the macroscopic properties of vehicular flow. In particular, we study the qualitative structure of the resulting flux-density and speed-density diagrams for different choices of the desired speeds. We are able to recover multivalued diagrams as a result of the existence of a one-parameter family of stationary distributions, whose expression is analytically found by means of a Fokker-Planck approximation of the initial Boltzmann-type model.

  9. Interpreting Evolutionary Diagrams: When Topology and Process Conflict

    Science.gov (United States)

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

    2010-01-01

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

  10. Dark energy in six nearby galaxy flows: Synthetic phase diagrams and self-similarity

    Science.gov (United States)

    Chernin, A. D.; Teerikorpi, P.; Dolgachev, V. P.; Kanter, A. A.; Domozhilova, L. M.; Valtonen, M. J.; Byrd, G. G.

    2012-09-01

    Outward flows of galaxies are observed around groups of galaxies on spatial scales of about 1 Mpc, and around galaxy clusters on scales of 10 Mpc. Using recent data from the Hubble Space Telescope (HST), we have constructed two synthetic velocity-distance phase diagrams: one for four flows on galaxy-group scales and the other for two flows on cluster scales. It has been shown that, in both cases, the antigravity produced by the cosmic dark-energy background is stronger than the gravity produced by the matter in the outflow volume. The antigravity accelerates the flows and introduces a phase attractor that is common to all scales, corresponding to a linear velocity-distance relation (the local Hubble law). As a result, the bundle of outflow trajectories mostly follow the trajectory of the attractor. A comparison of the two diagrams reveals the universal self-similar nature of the outflows: their gross phase structure in dimensionless variables is essentially independent of their physical spatial scales, which differ by approximately a factor of 10 in the two diagrams.

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

    CERN Document Server

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

    2014-01-01

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

  12. Solids flow diagram of a CFB riser using Geldart B-type powders

    Institute of Scientific and Technical Information of China (English)

    Shiva Mahmoudi; Chian Wen Chan; Anke Brems; Jonathan Seville; Jan Baeyens

    2012-01-01

    Riser operating modes are vital to designing a circulating fluidized bed (CFB) reactor for a required process of either a gas-solid or a gas-catalytic nature.Different operating modes provide different solids' residence times and mixing behaviors,which define the reactions' efficiency and yield.The literature demonstrates distinct operating modes resulting from observed differences in slip factors and the range of particle velocities and their associated residence time distribution.The present research uses positron emission particle tracking (PEPT) in a riser of B-type bed material to determine the different operating modes by measuring (i) particle velocities and residence time distribution,(ii) population densities of these particles in the cross-sectional area of the riser,and (iii) solids flow pattern at the bottom of the riser.Data treatment defines four distinct solids hold-up regimes in the riser and proposes a “phase diagram” depicting the existence of the different operating modes (dilute,dense,core-annulus and combined) as a function of the superficial gas velocity and solids circulation flux in the riser.The delineated regimes have good agreement with available literature data and known industrial operations.Comparison with literature data for risers using A-type powders is also fair.The diagram enables CFB designers to better delineate operating characteristics.

  13. Information Flow in the Launch Vehicle Design/Analysis Process

    Science.gov (United States)

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

    1999-01-01

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

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

    CERN Document Server

    Bogart, Richard S; Baldner,; Basu, Sarbani

    2015-01-01

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

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

    Science.gov (United States)

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

    2007-01-01

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

  16. HORIZONTAL FLOWS IN ACTIVE REGIONS FROM RING-DIAGRAM AND LOCAL CORRELATION TRACKING METHODS

    Energy Technology Data Exchange (ETDEWEB)

    Jain, Kiran; Tripathy, S. C.; Komm, R.; Hill, F. [National Solar Observatory, 950 N Cherry Avenue, Tucson, AZ 85719 (United States); Ravindra, B., E-mail: kjain@nso.edu [Indian Institute of Astrophysics, Block 2, Koramangala, Bangaluru, 560034 (India)

    2016-01-01

    Continuous high-cadence and high spatial resolution Dopplergrams allow us to study subsurface dynamics that may be further extended to explore precursors of visible solar activity on the surface. Since the p-mode power is absorbed in the regions of high magnetic field, the inferences in these regions are often presumed to have large uncertainties. In this paper, using the Dopplergrams from space-borne Helioseismic Magnetic Imager, we compare horizontal flows in a shear layer below the surface and the photospheric layer in and around active regions. The photospheric flows are calculated using the local correlation tracking (LCT) method, while the ring-diagram technique of helioseismology is used to infer flows in the subphotospheric shear layer. We find a strong positive correlation between flows from both methods near the surface. This implies that despite the absorption of acoustic power in the regions of strong magnetic field, the flows inferred from the helioseismology are comparable to those from the surface measurements. However, the magnitudes are significantly different; the flows from the LCT method are smaller by a factor of 2 than the helioseismic measurements. Also, the median difference between the direction of corresponding vectors is 49°.

  17. A rigorous semantics for BPMN 2.0 process diagrams

    CERN Document Server

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

    2015-01-01

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

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

    Science.gov (United States)

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

    2015-10-22

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

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

    CERN Document Server

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

    2015-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    FONG, S.K.

    1998-11-11

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

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

    Science.gov (United States)

    de Oliveira, Marcelo Martins; Dickman, Ronald

    2014-09-01

    We study the two-species symbiotic contact process, recently proposed by de Oliveira, Santos, and Dickman [Phys. Rev. E 86, 011121 (2012), 10.1103/PhysRevE.86.011121]. In this model, each site of a lattice may be vacant or host single individuals of species A and/or B. Individuals at sites with both species present interact in a symbiotic manner, having a reduced death rate μ effects of asymmetric creation rates and diffusion of individuals. In two dimensions, for sufficiently strong symbiosis (i.e., small μ), the absorbing-state phase transition becomes discontinuous for diffusion rates D within a certain range. We report preliminary results on the critical surface and tricritical line in the λ-μ-D space. Our results raise the possibility that strongly symbiotic associations of mobile species may be vulnerable to sudden extinction under increasingly adverse conditions.

  2. Estimation of Energy Consumption in COREX Process Using a Modified Rist Operating Diagram

    Institute of Scientific and Technical Information of China (English)

    Wen-long ZHAN; Keng WU; Zhi-jun HE; Qi-hang LIU; Xiao-juan WU

    2015-01-01

    Fuel consumption in the COREX-3000 process run in Baosteel is currently higher than the design index. Therefore,mass and heat balance equations for the COREX process were established using the basic principles in-cluded in the Rist operating diagram for blast furnace (BF)as a reference.Thermodynamic calculations were then used to modify the Rist operating diagram so that it was suitable for the COREX process.The modified Rist operating dia-gram was then applied for the evaluation of metallization rate (MR)and fuel structure to reduce the energy consump-tion in the COREX process.The modified Rist operating diagram for the shaft furnace (SF)provided a nearly ideal value for the restriction point W when the metallization rate was increased,while the point P on the operating line for the melter gasifier (MG)moved upward due to reduction in the heat required in hearth.The feasibility of reduc-ing the energy consumption during the COREX process by changing the fuel structure was also demonstrated.

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

    Science.gov (United States)

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

    1981-01-01

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

  4. Intermediate regime and a phase diagram of red blood cell dynamics in a linear flow

    Science.gov (United States)

    Levant, Michael; Steinberg, Victor

    2016-12-01

    In this paper we investigate the in vitro dynamics of a single rabbit red blood cell (RBC) in a planar linear flow as a function of a shear stress σ and the dynamic viscosity of outer fluid ηo. A linear flow is a generalization of previous studies dynamics of soft objects including RBC in shear flow and is realized in the experiment in a microfluidic four-roll mill device. We verify that the RBC stable orientation dynamics is found in the experiment being the in-shear-plane orientation and the RBC dynamics is characterized by observed three RBC dynamical states, namely tumbling (TU), intermediate (INT), and swinging (SW) [or tank-treading (TT)] on a single RBC. The main results of these studies are the following. (i) We completely characterize the RBC dynamical states and reconstruct their phase diagram in the case of the RBC in-shear-plane orientation in a planar linear flow and find it in a good agreement with that obtained in early experiments in a shear flow for human RBCs. (ii) The value of the critical shear stress σc of the TU-TT(SW) transition surprisingly coincides with that found in early experiments in spite of a significant difference in the degree of RBC shape deformations in both the SW and INT states. (iii) We describe the INT regime, which is stationary, characterized by strong RBC shape deformations and observed in a wide range of the shear stresses. We argue that our observations cast doubts on the main claim of the recent numerical simulations that the only RBC spheroidal stress-free shape is capable to explain the early experimental data. Finally, we suggest that the amplitude dependence of both θ and the shape deformation parameter D on σ can be used as the quantitative criterion to determine the RBC stress-free shape.

  5. Calculating Method for Influence of Material Flow on Energy Consumption in Steel Manufacturing Process

    Institute of Scientific and Technical Information of China (English)

    YU Qing-bo; LU Zhong-wu; CAI Jiu-ju

    2007-01-01

    From the viewpoint of systems energy conservation, the influences of material flow on its energy consumption in a steel manufacturing process is an important subject. The quantitative analysis of the relationship between material flow and the energy intensity is useful to save energy in steel industry. Based on the concept of standard material flow diagram, all possible situations of ferric material flow in steel manufacturing process are analyzed. The expressions of the influence of material flow deviated from standard material flow diagram on energy consumption are put forward.

  6. Flow generating processes

    NARCIS (Netherlands)

    Lanen, van H.A.J.; Fendeková, M.; Kupczyk, E.; Kasprzyk, A.; Pokojski, W.

    2004-01-01

    This chapter starts with an overview of how climatic water deficits affect hydrological processes in different type of catchments. It then continues with a more comprehensive description of drought relevant processes. Two catchments in climatologically contrasting regions are used for illustrative p

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

    OpenAIRE

    1999-01-01

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

  8. Heat flow diagrams with and without a deaerator for steam turbine plants with T-250/300-23.5 turbines

    Science.gov (United States)

    Valamin, A. E.; Kultyshev, A. Yu.; Shibaev, T. L.; Gol'dberg, A. A.; Stepanov, M. Yu.

    2016-11-01

    A T-250/300-240 turbine (currently known as T-250/300-23.5), which is operated at 31 steam turbine plants, is the largest in the world extraction turbine (by the heating extraction load) and one of the largest by the nominal capacity. All steam turbine plants equipped with T-250/300-23.5 turbines of different modifications are operated in large cities of Russia and the neighboring countries covering a significant part of the needs of cities for the electric power and almost fully supplying them with heat power. The design life of a significant part of the operated steam turbine plants of this family is either expired or almost expired. It refers to both the turbine unit (including a turbine and a generator) and the turbine plant equipment. For steam turbine plants equipped with T-250/300-23.5 turbines, which were initially designed and mounted for work with deaerators at electric power stations, the heat flow diagrams with and without a deaerator were compared. The main advantages and disadvantages of each scheme were shown. It was concluded that, for the newly constructed power units with supercritical steam parameters, it is preferable to use the heat flow diagram without a deaerator; for the upgraded blocks, if there are no objective reasons for the removal of a deaerator, it is recommended to keep the existing heat flow diagram of a turbine plant.

  9. Simulating the special features of fundamental diagrams observed by Mori-Tsukaguchi and Helbing et al in uni-directional pedestrian flow

    Science.gov (United States)

    Jin, Cheng-Jie; Jiang, Rui

    2017-02-01

    The pedestrian flow dynamics are very complex. Even the fundamental diagrams of uni-directional pedestrian flow exhibit diversity. In the empirical data of Mori-Tsukaguchi and Helbing et al, the flows drop drastically with medium densities and nearly keep constant with high densities, which is different from many other empirical and experimental results. To simulate these special phenomena with cellular automaton (CA) models, we use the new configuration, in which the occupied area of each pedestrian is 0.4 m * 0.2 m. The modeling framework is based on the ITP model, which is a two-process CA model presented in our previous paper, and one new rule is added: when the local density behind is below a threshold, pedestrians prefer to keep a certain front gap. With the simple rule, the new fundamental diagrams can qualitatively coincide with the empirical facts of Mori-Tsukaguchi and Helbing et al. Some other results, including simulation patterns and velocities of pedestrians can further confirm the validity of the new rule, and give some explanations for the diversity of different empirical data. These results are useful contributions for pedestrian flow modeling.

  10. Analysis of Business Process at PT XYZ by Using SCOR Thread Diagram

    Science.gov (United States)

    Sembiring, M. T.; Rambe, H. C.

    2017-03-01

    Supply Chain Operations Reference (SCOR) is a standard supply chain performance evaluation model which is proposed by Supply Chain Council (SCC). SCOR makes companies can analyse and evaluate their supply chain performance. SCOR has Thread Diagram which describes business process simply and systematically to help the analysis of company’s business process. This research takes place in PT XYZ that is involved in Crude Palm Oil (CPO) industry. PT XYZ used to be the market leader of CPO industry but nowadays they have a trouble to compete with new competitors. The purpose of this study is to provide the input for PT XYZ business process improvement to enhance the competitiveness of the company with the others. The result obtained shows that there are two performance metrics that are not reached. The analysis of business process shows the lack of control role of PT XYZ to supplier and customer side which is going to be the suggestion of improvement.

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

    Science.gov (United States)

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

    2015-12-20

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

  12. Flow Logic for Process Calculi

    DEFF Research Database (Denmark)

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

    2012-01-01

    Flow Logic is an approach to statically determining the behavior of programs and processes. It borrows methods and techniques from Abstract Interpretation, Data Flow Analysis and Constraint Based Analysis while presenting the analysis in a style more reminiscent of Type Systems. Traditionally...... developed for programming languages, this article provides a tutorial development of the approach of Flow Logic for process calculi based on a decade of research. We first develop a simple analysis for the π-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...

  13. FORM, Diagrams and Topologies

    CERN Document Server

    Herzog, Franz; Ueda, Takahiro; Vermaseren, J A M; Vogt, Andreas

    2016-01-01

    We discuss a number of FORM features that are essential in the automatic processing of very large numbers of diagrams as used in the Forcer program for 4-loop massless propagator diagrams. Most of these features are new.

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

    Science.gov (United States)

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

    2014-06-01

    Ring-diagram analysis of acoustic waves observed at the photosphere provides in principle a relatively robust determination of the sub-surface flows at a particular time under a particular region. The depth of penetration of the waves is related to the size of the region, hence the depth extent of the measured flows is inversely proportional to the spatial resolution. Most ring-analysis has focused on regions of extent ~15 deg (200 Mm) or more in order to provide reasonable mode sets for inversions. The HMI analysis pipeline however also provides a set of ring fit parameters on a scale three times smaller. These provide flow estimates for the outer 1% (7 Mm) of the Sun only, with very limited depth resolution, but with spatial resolution adequate to map structures.potentially associated with the belts and regions of magnetic activity. There are a number of systematic effects affecting the determination of flows from local helioseismic analysis of regions over different parts of the observable disc, not all well-understood. In this study we characterize those systematic effects with higher spatial resolution. This enable us to remove them more effectively as we map the temporal and spatial evolution of the flows, leaving open the question of their mean structure which is most affected by the systematics. We present results for the ring-diagram determination of the flow anomalies corresponding to the torsional oscillation pattern in differential rotation and analogous patterns in the meridional cell structure over the early part of the current solar cycle observed by HMI.

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

    NARCIS (Netherlands)

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

    2014-01-01

    Direct numerical simulations of Taylor–Couette flow, i.e. the flow between two coaxial and independently rotating cylinders, were performed. Shear Reynolds numbers of up to 3×10 5 , corresponding to Taylor numbers of Ta=4.6×10 10 , were reached. Effective scaling laws for the torque are presented.

  16. Effect of long range order on sheared liquid crystalline materials: flow regimes, transitions, and rheological phase diagrams

    Science.gov (United States)

    Tsuji; Rey

    2000-12-01

    A generalized theory that includes short-range elasticity, long-range elasticity, and flow effects is used to simulate and characterize the shear flow of liquid crystalline materials as a function of the Deborah (De) and Ericksen (Er) numbers in the presence of fixed planar director boundary conditions; the results are also interpreted as a function of the ratio R between short-range and long-range elasticity. The results are effectively summarized into rheological phase diagrams spanned by De and Er, and also by R and Er, where the stability region of four distinct flow regimes are indicated. The four regimes for planar (two-dimensional orientation) shear flow are (1) the elastic-driven steady state, (2) the composite tumbling-wagging periodic state, (3) the wagging periodic state, and (4) the viscous-driven steady state. The coexistence of the four regimes at a quacritical point is shown to be due to the emergence of a defect structure. The origin, the significant steady and dynamical features, and the transitions between these regimes are thoroughly characterized and analyzed. Quantitative and qualitative comparisons between the present complete model predictions and those obtained from the classical theories of nematodynamics (Leslie-Ericksen and Doi theories) are presented and the main physical mechanisms that drive the observed deviations between the predictions of these models are identified. The presented results fill the previously existing gap between the classical Leslie-Ericksen theory and the Doi theory, and present a unified description of nematodynamics.

  17. Application of Windows Socket Technique to Communication Process of the Train Diagram Network System Based on Client/Server Structure

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper is focused on the technique for design and realization of the process communications about the computer-aided train diagram network system. The Windows Socket technique is adopted to program for the client and the server to create system applications and solve the problems of data transfer and data sharing in the system.

  18. Structured Analysis and the Data Flow Diagram: Tools for Library Analysis.

    Science.gov (United States)

    Carlson, David H.

    1986-01-01

    This article discusses tools developed to aid the systems analysis process (program evaluation and review technique, Gantt charts, organizational charts, decision tables, flowcharts, hierarchy plus input-process-output). Similarities and differences among techniques, library applications of analysis, structured systems analysis, and the data flow…

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

    Energy Technology Data Exchange (ETDEWEB)

    Tetreault, T. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Regenthal, S. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2011-05-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Tetreault, T.; Regenthal, S.

    2011-05-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Som, A. [General Electric Company, SC (United States)

    2001-07-01

    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)

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

    KAUST Repository

    Qiu, Shanwen

    2013-09-01

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

  3. Visualization design and verification of Ada tasking using timing diagrams

    Science.gov (United States)

    Vidale, R. F.; Szulewski, P. A.; Weiss, J. B.

    1986-01-01

    The use of timing diagrams is recommended in the design and testing of multi-task Ada programs. By displaying the task states vs. time, timing diagrams can portray the simultaneous threads of data flow and control which characterize tasking programs. This description of the system's dynamic behavior from conception to testing is a necessary adjunct to other graphical techniques, such as structure charts, which essentially give a static view of the system. A series of steps is recommended which incorporates timing diagrams into the design process. Finally, a description is provided of a prototype Ada Execution Analyzer (AEA) which automates the production of timing diagrams from VAX/Ada debugger output.

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

    Directory of Open Access Journals (Sweden)

    A. M. P Azevedo

    2006-07-01

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

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

    Directory of Open Access Journals (Sweden)

    Amy eRouinfar

    2014-09-01

    Full Text Available This study investigated links between lower-level visual attention processes and higher-level problem solving. This was done by overlaying visual cues on conceptual physics problem diagrams to direct participants’ attention to relevant areas to facilitate problem solving. Participants (N = 80 individually worked through four problem sets, each containing a diagram, while their eye movements were recorded. Each diagram contained regions that were relevant to solving the problem correctly and separate regions related to common incorrect responses. Problem sets contained an initial problem, six isomorphic training problems, and a transfer problem. The cued condition saw visual cues overlaid on the training problems. Participants’ verbal responses were used to determine their accuracy. The study produced two major findings. First, short duration visual cues can improve problem solving performance on a variety of insight physics problems, including transfer problems not sharing the surface features of the training problems, but instead sharing the underlying solution path. Thus, visual cues can facilitate re-representing a problem and overcoming impasse, enabling a correct solution. Importantly, these cueing effects on problem solving did not involve the solvers’ attention necessarily embodying the solution to the problem. Instead, the cueing effects were caused by solvers attending to and integrating relevant information in the problems into a solution path. Second, these short duration visual cues when administered repeatedly over multiple training problems resulted in participants becoming more efficient at extracting the relevant information on the transfer problem, showing that such cues can improve the automaticity with which solvers extract relevant information from a problem. Both of these results converge on the conclusion that lower-order visual processes driven by attentional cues can influence higher-order cognitive processes

  6. Electronic diagrams

    CERN Document Server

    Colwell, Morris A

    1976-01-01

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

  7. SCADA Diagram

    OpenAIRE

    Rose, Matthew

    2004-01-01

    Matthew Rose worked at the Naval Postgraduate School as a graphic designer from February 2002-November 2011. His work for NPS included logos, brochures, business packs, movies/presentations, posters, the CyberSiege video game and many other projects. This material was organized and provided by the artist, for inclusion in the NPS Archive, Calhoun. Includes these files: Plan_ver.ai; powerline.jpg; SCADA diagram.ai; SCADA diagram.pdf; SCADA diagramsmall.pdf; SCADA2.pdf

  8. 支持群决策过程建模的层次影响图模型%Hierarchical influence diagrams for group decision process modeling

    Institute of Scientific and Technical Information of China (English)

    胡笑旋; 杨善林; 张强

    2011-01-01

    The use of traditional influence diagrams (Ids) for group decision-making modeling is limited. For this reason, a framework of hierarchical influence diagrams (HIDs) was proposed. First the definition of hierarchical influence diagrams was given, which is a set of influence diagrams organized in a hierarchical way. Those influence diagrams communicate with each other by three types of message passing. Then the evaluation algorithm for hierarchical influence diagrams was defined. Finally the HIDs modeling and evaluation process was illustrated using a group decision-making case. Hierarchical influence diagrams framework is a decomposition and combination methodology for decision-making process modeling, which widen the scope of application of influence diagrams into group decision making field.%传统影响图模型不具备对群决策过程的建模能力.针对这一问题,提出了层次影响图模型.首先给出了层次影响图的定义,它是一个以层次方式排列的影响图的集合.然后建立了不同影响图之间的三种消息传递方式,研究了在能够接收外界消息情况下的影响图演算方法.最后使用一个群决策案例展示了建模和求解的过程.层次影响图采用了分解-联合的建模策略,将影响图的应用范围扩展到群决策领域.

  9. Delimiting diagrams

    NARCIS (Netherlands)

    Oostrom, V. van

    2008-01-01

    We introduce the unifying notion of delimiting diagram. Hitherto unrelated results such as: Minimality of the internal needed strategy for orthogonal first-order term rewriting systems, maximality of the limit strategy for orthogonal higher-order pattern rewrite systems (with maximality of the strat

  10. Process optimization diagram based on FEM simulation for extrusion of AZ31 profile

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The ram speed and the billet temperature are the primary process variables that determine the quality of the extruded magnesium profile and the productivity of the extrusion operation.The optimization of the extrusion process concerns the interplay between these two variables in relation to the extrudate temperature and the peak extrusion pressure The 3D computer simulations were performed to determine the eriects of the ram speed and the billet temperature on the extrudate temperature and the peak extrusion pressure,thereby providing guidelines for the process optimization and minimizing the number of trial extrusion runs needed for the process optimization.A case study on the extrusion of an AZ31 X-shaped profile was conducted.The correlations between the process variables and the response from the deformed material,extrudate temperature and peak extrusion pressure,were established from the 3D FEM simulations and verified by the experiment.The research opens up a way to rational selection of the process variables for ensured quality and maximum productivity of the magnesium extrusion.

  11. Hubble Diagram

    Science.gov (United States)

    Djorgovski, S.; Murdin, P.

    2000-11-01

    Initially introduced as a way to demonstrate the expansion of the universe, and subsequently to determine the expansion rate (the HUBBLE CONSTANT H0), the Hubble diagram is one of the classical cosmological tests. It is a plot of apparent fluxes (usually expressed as magnitudes) of some types of objects at cosmological distances, against their REDSHIFTS. It is used as a tool to measure the glob...

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

    Science.gov (United States)

    Varzakas, Theodoros H

    2011-09-01

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

  13. The perceptual flow of phonetic feature processing

    DEFF Research Database (Denmark)

    Greenberg, Steven; Christiansen, Thomas Ulrich

    2008-01-01

    , 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...

  14. Experimental and Numerical Study on Forming Limit Diagrams of 304 Stainless Steel Tubes in the Hydroforming Process

    Science.gov (United States)

    Naghibi, Mahdi Falahati; Gerdooei, Mahdi; Jooybari, Mohammad Bakhshi

    2016-12-01

    Tearing as a factor that restricts formability of sheets and tubes is determined by forming limit diagram (FLD). The aim of the current study is to present a novel approach to achieve FLD of a metallic tube using hydroforming process. Here, for 304 stainless steel tubes, various loading conditions, namely free loading, bulging with axial feeding and bulging with closed end, were considered. Along with loading condition, die geometries with different corner radius and deformation width were studied on the strain path and plastic instability. The effects of process parameters on the strain path have been evaluated and simulated using ABAQUS/Explicit. Meshed tubes were bulged under controlled loading, and the FLD was drawn after measuring the major and minor strains close to the tearing location. Finally, the evaluation of the current method has been investigated by using the obtained FLD in the forming of an industrial part (i.e., the cam-shaped tube). The results revealed that the proposed approach has the capability to predict the formability of industrial components.

  15. Disjunctive Information Flow for Communicating Processes

    DEFF Research Database (Denmark)

    Li, Ximeng; Nielson, Flemming; Nielson, Hanne Riis;

    2016-01-01

    processes according to their tagging. We devise a security type system that enforces content-dependent information flow policies in the presence of communication and concurrency. The type system soundly guarantees a compositional noninterference property. All theoretical results have been formally proved......The security validation of practical computer systems calls for the ability to specify and verify information flow policies that are dependent on data content. Such policies play an important role in concurrent, communicating systems: consider a scenario where messages are sent to different...

  16. Program Synthesizes UML Sequence Diagrams

    Science.gov (United States)

    Barry, Matthew R.; Osborne, Richard N.

    2006-01-01

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

  17. 抽象概念结构图到JAVA过程蓝图的平滑过渡及一致性%Smooth Transition from Abstract Concept Structure Diagram to JAVA Process Blueprint and Their Consistency

    Institute of Scientific and Technical Information of China (English)

    刘建宾; 郝克刚; 龚世生

    2001-01-01

    Abstract Concept Structure Diagram,an Abstract diagrammatized representation for program process logic ,is a concept algorithm description tool independent of program implementing language. In this paper ,a formal model of Abstract Concept Structure Diagram,its graphical notations,and a smooth transition method from Abstract Concept Structure Diagram to JAVA Process Blueprint and mapping rules are presented. The validation and consistency of concept program and logical program is defined,and related theorems and prove procedures are also presented.

  18. Visualizing Flow of Uncertainty through Analytical Processes.

    Science.gov (United States)

    Wu, Yingcai; Yuan, Guo-Xun; Ma, Kwan-Liu

    2012-12-01

    Uncertainty can arise in any stage of a visual analytics process, especially in data-intensive applications with a sequence of data transformations. Additionally, throughout the process of multidimensional, multivariate data analysis, uncertainty due to data transformation and integration may split, merge, increase, or decrease. This dynamic characteristic along with other features of uncertainty pose a great challenge to effective uncertainty-aware visualization. This paper presents a new framework for modeling uncertainty and characterizing the evolution of the uncertainty information through analytical processes. Based on the framework, we have designed a visual metaphor called uncertainty flow to visually and intuitively summarize how uncertainty information propagates over the whole analysis pipeline. Our system allows analysts to interact with and analyze the uncertainty information at different levels of detail. Three experiments were conducted to demonstrate the effectiveness and intuitiveness of our design.

  19. Advanced Recording and Preprocessing of Physiological Signals. [data processing equipment for flow measurement of blood flow by ultrasonics

    Science.gov (United States)

    Bentley, P. B.

    1975-01-01

    The measurement of the volume flow-rate of blood in an artery or vein requires both an estimate of the flow velocity and its spatial distribution and the corresponding cross-sectional area. Transcutaneous measurements of these parameters can be performed using ultrasonic techniques that are analogous to the measurement of moving objects by use of a radar. Modern digital data recording and preprocessing methods were applied to the measurement of blood-flow velocity by means of the CW Doppler ultrasonic technique. Only the average flow velocity was measured and no distribution or size information was obtained. Evaluations of current flowmeter design and performance, ultrasonic transducer fabrication methods, and other related items are given. The main thrust was the development of effective data-handling and processing methods by application of modern digital techniques. The evaluation resulted in useful improvements in both the flowmeter instrumentation and the ultrasonic transducers. Effective digital processing algorithms that provided enhanced blood-flow measurement accuracy and sensitivity were developed. Block diagrams illustrative of the equipment setup are included.

  20. Scaffolding Cognitive and Metacognitive Processes in Low Verbal Ability Learners: Use of Diagrams in Computer-Based Training Environments.

    Science.gov (United States)

    Cuevas, Haydee M.; Fiore, Stephen M.; Oser, Randall L.

    2002-01-01

    This study of undergraduates investigated how scaffolding instructional strategies can support learners' knowledge acquisition and metacomprehension of complex systems in a computer-based training environment. Results showed that incorporating diagrams facilitated performance on measures of integrative knowledge and facilitated the development of…

  1. From State Diagram to Class Diagram

    DEFF Research Database (Denmark)

    Borch, Ole; Madsen, Per Printz

    2009-01-01

    UML class diagram and Java source code are interrelated and Java code is a kind of interchange format. Working with UML state diagram in CASE tools, a corresponding xml file is maintained. Designing state diagrams is mostly performed manually using design patterns and coding templates - a time...

  2. Nitrocarburizing treatments using flowing afterglow processes

    Science.gov (United States)

    Jaoul, C.; Belmonte, T.; Czerwiec, T.; David, N.

    2006-09-01

    Nitrocarburizing of pure iron samples is achieved at 853 K and is easily controlled by introducing C 3H 8 in the afterglow of a flowing microwave Ar-N 2-H 2 plasma. The carbon uptake in the solid is actually possible with methane but strongly limited. The use of propane enhances the carbon flux and the ɛ/α configuration is synthesized for the first time by this kind of process. For this stack, diffusion paths in the ternary system determined from chemical analyses by secondary neutral mass spectrometry reproduce satisfactorily X-ray diffraction results which only reveal, as optical micrographs, ɛ and α phases. Propane offers an accurate control of the nitrocarburizing conditions. As an example, a modulation of N and C contents in iron could be achieved to create new carbonitride multilayers.

  3. Nitrocarburizing treatments using flowing afterglow processes

    Energy Technology Data Exchange (ETDEWEB)

    Jaoul, C. [Laboratoire de Science et Genie des Surfaces (UMR CNRS 7570), Ecole des Mines, Parc de Saurupt, 54042 Nancy Cedex (France); Belmonte, T. [Laboratoire de Science et Genie des Surfaces (UMR CNRS 7570), Ecole des Mines, Parc de Saurupt, 54042 Nancy Cedex (France)]. E-mail: Thierry.Belmonte@mines.inpl-nancy.fr; Czerwiec, T. [Laboratoire de Science et Genie des Surfaces (UMR CNRS 7570), Ecole des Mines, Parc de Saurupt, 54042 Nancy Cedex (France); David, N. [Laboratoire de Chimie du Solide Mineral, Universite Henri Poincare Nancy-I, Vandoeuvre-Les-Nancy (France)

    2006-09-30

    Nitrocarburizing of pure iron samples is achieved at 853 K and is easily controlled by introducing C{sub 3}H{sub 8} in the afterglow of a flowing microwave Ar-N{sub 2}-H{sub 2} plasma. The carbon uptake in the solid is actually possible with methane but strongly limited. The use of propane enhances the carbon flux and the {epsilon}/{alpha} configuration is synthesized for the first time by this kind of process. For this stack, diffusion paths in the ternary system determined from chemical analyses by secondary neutral mass spectrometry reproduce satisfactorily X-ray diffraction results which only reveal, as optical micrographs, {epsilon} and {alpha} phases. Propane offers an accurate control of the nitrocarburizing conditions. As an example, a modulation of N and C contents in iron could be achieved to create new carbonitride multilayers.

  4. Causal diagrams for physical models

    CERN Document Server

    Kinsler, Paul

    2015-01-01

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

  5. Concentrated flow erosion processes under planned fire

    Science.gov (United States)

    Langhans, Christoph; Noske, Phil; Van Der Sant, Rene; Lane, Patrick; Sheridan, Gary

    2016-04-01

    The role of wildfire in accelerating erosion rates for a certain period after fire has been well documented. Much less information is available on the erosion rates and processes after planned fires that typically burn at much lower intensity. Observational evidence, and some studies in southern and southeastern Australia suggest that erosion after planned fire can be significant if rainfall intensities exceed critical intensities and durations. Understanding erosion processes and rates under these event conditions is of critical importance for planning of burn locations away from critical human assets such as water supplies and infrastructure. We conducted concentrated flow experiments with the purpose to understand what critical conditions are required for significant erosion to occur on planned burn hillslopes. Concentrated flow runon was applied on pre-wetted, unbounded plots of 10 m at rates of 0.5, 1, 1.5 and 2 L/s, with three replicates for each rates applied at 1m distance of each other. The experiments were carried out at three sites within one burn perimeter with different burn severities ranging from low to high, with two replicates at each site. Runon was applied until an apparent steady state in runoff was reached at the lower plot boundary, which was typically between 0.7 and 2.5 minutes. The experiments were filmed and erosion depth was measured by survey methods at 1m intervals. Soil surface properties, including potential sediment trapping objects were measured and surveyed near the plots. We found that fire severity increased plot scale average erosion depth significantly even as experiments were typically much shorter on the high severity plots. Unit stream power was a good predictor for average erosion depth. Uncontrolled for variations in soil surface properties explained process behaviour: finer, ash rich surface material was much less likely to be trapped by fallen, charred branches and litter than coarser, ash-depleted material. Furthermore

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

    Science.gov (United States)

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

    1981-01-01

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

  7. Stochastic subspsace parameter identification and stability diagram of gas-liquid two-phase flow patterns%基于随机子空间结合稳定图的气液两相流型分析

    Institute of Scientific and Technical Information of China (English)

    李洪伟; 周云龙; 刘旭; 孙斌

    2012-01-01

    The characteristics of stability diagram of several typical flow patterns are studied,and the signals of flow patterns under 47 kinds of flowing conditions are identified with stochastic subspace parameter identification.The results show that the characteristic of a stability diagram can reflect the internal characteristics of complex time series,the characteristics of time series can be quantified by extracted straightness characteristics and the differences of characteristics of stability diagrams of three typical flow patterns.The characteristics of stability diagrams of bubble flow are the most confused and followed by Mist flows'.Slug flows' are the most regular.The extraction and recognition for characteristics of gray fluctuation sequence of gas-liquid two-phase images and the accurate classification for flow pattern samples provide a new path for the classification of multi-phase flow patterns.At the same time,the stability diagram analysis method provides a useful exploration for the further revelation of flowing mechanism of multi-phase flows.%研究了儿种典型气液两相干流流型的稳定图特征,并应用随机子空间方法对47种流动条件下的流型信号进行了识别.研究结果表明:稳定图特征能够反映出复杂时间序列的内部特征,利用其提取的直线度特征值可以对时间序列的特征进行量化分析,三种典型流型的稳定图特征差异较明显,泡状流的稳定图特征最为混乱.雾状流次之.段塞流量为规整.应用随机子空间方法对气液两相流图像灰度波动序列进行特征向量提取和辨识,通过幅值以及相角的分布特征能够对不同工况下的流型样本进行准确分类,为多相流的分类提供了一条新路径.同时基于稳定图的分析方法为进一步揭示多相流的流动机理提供有益的探索.

  8. Breviz: Visualizing Spreadsheets using Dataflow Diagrams

    CERN Document Server

    Hermans, Felienne; van Deursen, Arie

    2011-01-01

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

  9. Fluid flow for chemical and process engineers

    CERN Document Server

    Holland, F

    1995-01-01

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

  10. Using Affinity Diagrams to Evaluate Interactive Prototypes

    DEFF Research Database (Denmark)

    Lucero, Andrés

    2015-01-01

    Affinity diagramming is a technique used to externalize, make sense of, and organize large amounts of unstructured, far-ranging, and seemingly dissimilar qualitative data. HCI and interaction design practitioners have adopted and used affinity diagrams for different purposes. This paper discusses...... our particular use of affinity diagramming in prototype evaluations. We reflect on a decade’s experience using affinity diagramming across a number of projects, both in industry and academia. Our affinity diagramming process in interaction design has been tailored and consists of four stages: creating...

  11. Origin and use of crystallization phase diagrams.

    Science.gov (United States)

    Rupp, Bernhard

    2015-03-01

    Crystallization phase diagrams are frequently used to conceptualize the phase relations and also the processes taking place during the crystallization of macromolecules. While a great deal of freedom is given in crystallization phase diagrams owing to a lack of specific knowledge about the actual phase boundaries and phase equilibria, crucial fundamental features of phase diagrams can be derived from thermodynamic first principles. Consequently, there are limits to what can be reasonably displayed in a phase diagram, and imagination may start to conflict with thermodynamic realities. Here, the commonly used `crystallization phase diagrams' are derived from thermodynamic excess properties and their limitations and appropriate use is discussed.

  12. 鱼骨图和流程图在开放性创伤手术感染管理中的应用%Application of fishbone diagram and flow chart in infection control for open trauma surgery

    Institute of Scientific and Technical Information of China (English)

    曹新平

    2013-01-01

    Objective To explore an infection control method for open trauma surgery using fishbone diagram and flow chart. Methods A fishbone diagram and a flow chart were drawn to identify the factors contributing to infection after open trauma surgery. Then 8 operating room nurses were were trained to use the fishbone diagram and the flow chart before the diagram and the chart were put into clinical practice. Results Before and after application of the fishbone diagram and the flow chart, nurses test scores in factors contributing to infection after open trauma surgery and infection control knowledge, rates of occupational exposures had significant differences(P<0. 01,P<0. 05) . The rate of accurate coping with an occupational exposure increased from 67. 31% to 100%. Conclusion Fishbone diagrams and flow charts which indentify the factors contributing to infection after open trauma surgery could effectively help nurses enhance the infection control quality of open trauma surgery, and decrease the incidence of occupational exposure.%目的 探讨鱼骨图和流程图在开放性创伤手术感染管理中的应用方法与效果.方法 制定开放性创伤手术感染因素鱼骨图和感染管理流程图,首先对手术室8名护士进行培训,然后将该图用于开放性创伤手术配合和管理中.结果 应用鱼骨图和流程图前后,护士开放性创伤手术易感因素和感染管理知识考核成绩、职业暴露率比较,差异有统计学意义(P<0.01,P<0.05);发生职业暴露后正确处理率由67.31%上升至100%.结论 应用开放性创伤手术感染因素鱼骨图和感染管理流程图,可以帮助护士有效提高开放性创伤手术的感染管理质量,降低职业暴露发生率.

  13. Diagramming Complex Activities

    DEFF Research Database (Denmark)

    Andersen, Peter Bøgh

    2005-01-01

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

  14. Similarities in basalt and rhyolite lava flow emplacement processes

    Science.gov (United States)

    Magnall, Nathan; James, Mike; Tuffen, Hugh; Vye-Brown, Charlotte

    2016-04-01

    Here we use field observations of rhyolite and basalt lava flows to show similarities in flow processes that span compositionally diverse lava flows. The eruption, and subsequent emplacement, of rhyolite lava flows is currently poorly understood due to the infrequency with which rhyolite eruptions occur. In contrast, the emplacement of basaltic lava flows are much better understood due to very frequent eruptions at locations such as Mt Etna and Hawaii. The 2011-2012 eruption of Cordón Caulle in Chile enabled the first scientific observations of the emplacement of an extensive rhyolite lava flow. The 30 to 100 m thick flow infilled a topographic depression with a negligible slope angle (0 - 7°). The flow split into two main channels; the southern flow advanced 4 km while the northern flow advanced 3 km before stalling. Once the flow stalled the channels inflated and secondary flows or breakouts formed from the flow front and margins. This cooling rather than volume-limited flow behaviour is common in basaltic lava flows but had never been observed in rhyolite lava flows. We draw on fieldwork conducted at Cordón Caulle and at Mt Etna to compare the emplacement of rhyolite and basaltic flows. The fieldwork identified emplacement features that are present in both lavas, such as inflation, breakouts from the flow font and margins, and squeeze-ups on the flow surfaces. In the case of Cordón Caulle, upon extrusion of a breakout it inflates due to a combination of continued lava supply and vesicle growth. This growth leads to fracturing and breakup of the breakout surface, and in some cases a large central fracture tens of metres deep forms. In contrast, breakouts from basaltic lava flows have a greater range of morphologies depending on the properties of the material in the flows core. In the case of Mt Etna, a range of breakout morphologies are observed including: toothpaste breakouts, flows topped with bladed lava as well as breakouts of pahoehoe or a'a lava. This

  15. Ion mixing and phase diagrams

    Science.gov (United States)

    Lau, S. S.; Liu, B. X.; Nicolet, M.-A.

    1983-05-01

    Interactions induced by ion irradiation are generally considered to be non-equilibrium processes, whereas phase diagrams are determined by phase equilibria. These two entities are seemingly unrelated. However, if one assumes that quasi-equilibrium conditions prevail after the prompt events, subsequent reactions are driven toward equilibrium by thermodynamical forces. Under this assumption, ion-induced reactions are related to equilibrium and therefore to phase diagrams. This relationship can be seen in the similarity that exists in thin films between reactions induced by ion irradiation and reactions induced by thermal annealing. In the latter case, phase diagrams have been used to predict the phase sequence of stable compound formation, notably so in cases of silicide formation. Ion-induced mixing not only can lead to stable compound formation, but also to metastable alloy formation. In some metal-metal systems, terminal solubilities can be greatly extended by ion mixing. In other cases, where the two constituents of the system have different crystal structures, extension of terminal solubility from both sides of the phase diagram eventually becomes structurally incompatible and a glassy (amorphous) mixture can form. The composition range where this bifurcation is likely to occur is in the two-phase regions of the phase diagram. These concepts are potentially useful guides in selecting metal pairs that from metallic glasses by ion mixing. In this report, phenomenological correlation between stable (and metastable) phase formation and phase diagram is discussed in terms of recent experimental data.

  16. Interpretation of the exergy equation for steady-flow processes

    NARCIS (Netherlands)

    Siemons, Roland V.

    1986-01-01

    We define and discuss the terms in exergy equations, with particular reference to the role of chemical terms in the exergy loss for steady-flow processes. Although there is a chemical contribution to exergy, exergy losses of steady-flow processes may be calculated by using a simple expression for th

  17. State Space Reduction of Linear Processes Using Control Flow Reconstruction

    NARCIS (Netherlands)

    Pol, van de Jaco; Timmer, Mark; Liu, Z.; Ravn, A.P.

    2009-01-01

    We present a new method for fighting the state space explosion of process algebraic specifications, by performing static analysis on an intermediate format: linear process equations (LPEs). Our method consists of two steps: (1) we reconstruct the LPE's control flow, detecting control flow parameters

  18. State Space Reduction of Linear Processes using Control Flow Reconstruction

    NARCIS (Netherlands)

    Pol, van de Jaco; Timmer, Mark

    2009-01-01

    We present a new method for fighting the state space explosion of process algebraic specifications, by performing static analysis on an intermediate format: linear process equations (LPEs). Our method consists of two steps: (1) we reconstruct the LPE's control flow, detecting control flow parameters

  19. Extrinsic Curvature Embedding Diagrams

    CERN Document Server

    Lu, J L

    2003-01-01

    Embedding diagrams have been used extensively to visualize the properties of curved space in Relativity. We introduce a new kind of embedding diagram based on the {\\it extrinsic} curvature (instead of the intrinsic curvature). Such an extrinsic curvature embedding diagram, when used together with the usual kind of intrinsic curvature embedding diagram, carries the information of how a surface is {\\it embedded} in the higher dimensional curved space. Simple examples are given to illustrate the idea.

  20. Progress in modeling of fluid flows in crystal growth processes

    Institute of Scientific and Technical Information of China (English)

    Qisheng Chen; Yanni Jiang; Junyi Yan; Ming Qin

    2008-01-01

    Modeling of fluid flows in crystal growth processes has become an important research area in theoretical and applied mechanics.Most crystal growth processes involve fluid flows,such as flows in the melt,solution or vapor.Theoretical modeling has played an important role in developing technologies used for growing semiconductor crystals for high performance electronic and optoelectronic devices.The application of devices requires large diameter crystals with a high degree of crystallographic perfection,low defect density and uniform dopant distribution.In this article,the flow models developed in modeling of the crystal growth processes such as Czochralski,ammono-thermal and physical vapor transport methods are reviewed.In the Czochralski growth modeling,the flow models for thermocapillary flow,turbulent flow and MHD flow have been developed.In the ammonothermal growth modeling,the buoyancy and porous media flow models have been developed based on a single-domain and continuum approach for the composite fluid-porous layer systems.In the physical vapor transport growth modeling,the Stefan flow model has been proposed based on the flow-kinetics theory for the vapor growth.In addition,perspectives for future studies on crystal growth modeling are proposed.

  1. Safety-barrier diagrams

    DEFF Research Database (Denmark)

    Duijm, Nijs Jan

    2007-01-01

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

  2. Phase Equilibria Diagrams Database

    Science.gov (United States)

    SRD 31 NIST/ACerS Phase Equilibria Diagrams Database (PC database for purchase)   The Phase Equilibria Diagrams Database contains commentaries and more than 21,000 diagrams for non-organic systems, including those published in all 21 hard-copy volumes produced as part of the ACerS-NIST Phase Equilibria Diagrams Program (formerly titled Phase Diagrams for Ceramists): Volumes I through XIV (blue books); Annuals 91, 92, 93; High Tc Superconductors I & II; Zirconium & Zirconia Systems; and Electronic Ceramics I. Materials covered include oxides as well as non-oxide systems such as chalcogenides and pnictides, phosphates, salt systems, and mixed systems of these classes.

  3. On Ladder Diagrams Compilation and Synthesis to FPGA Implemented Reconfigurable Logic Controller

    Directory of Open Access Journals (Sweden)

    Adam Milik

    2014-01-01

    Full Text Available The paper presents synthesis process of a hardware implemented reconfigurable logic controller from a ladder diagram according to IEC61131-3 requirements. It is focused on the originally developed a high-performance LD processing method. It is able to process a set of diagrams restricted to logic operations in a single clock cycle independently from the number of processed rungs. The paper considers the compilation of the ladder diagram into an intermediate form suitable for logic synthesis process according to developed processing method. The enhanced data flow graph (EDFG has been developed for the intermediate representation of an LD program. The original construction of the EDFG with attributed edges has been described. It allows for efficient representation and processing of logic and arithmetic formulas. The set of compilation algorithms that allow to preserve serial analysis order and to obtain massively parallel processing unit are presented. The overview of a hardware mapping concludes the presented considerations.

  4. RILL EROSION PROCESS AND RILL FLOW HYDRAULIC PARAMETERS

    Institute of Scientific and Technical Information of China (English)

    Fen-li ZHENG; Pei-qing XIAO; Xue-tian GAO

    2004-01-01

    In the rill erosion process,run-on water and sediment from upslope areas,and rill flow hydraulic parameters have significant effects on sediment detachment and transport.However,there is a lack of data to quantify the effects of run-on water and sediment and rill flow hydraulic parameters on rill erosion process at steep hillslopes,especially in the Loess Plateau of China.A dual-box system,consisting of a 2-m-long feeder box and a 5-m-long test box with 26.8% slope gradient was used to quantify the effects of upslope runoff and sediment,and of rill flow hydraulic parameters on the rill erosion process.The results showed that detachment-transport was dominated in rill erosion processes; upslope runoff always caused the net rill detachment at the downslope rill flow channel,and the net rill detachment caused by upslope runoff increased with a decrease of runoff sediment concentration from the feeder box or an increase of rainfall intensity.Upslope runoff discharging into the rill flow channel or an increase of rainfall intensity caused the rill flow to shift from a stratum flow into a turbulent flow.Upslope runoff had an important effect on rill flow hydraulic parameters,such as rill flow velocity,hydraulic radius,Reynolds number,Froude number and the Darcy-Weisbach resistance coefficient.The net rill detachment caused by upslope runoff increased as the relative increments of rill flow velocity,Reynolds number and Froude number caused by upslope runoff increased.In contrast,the net rill detachment decreased with an increase of the relative decrement of the Darcy-Weisbach resistance coefficient caused by upslope runoff.These findings will help to improve the understanding of the effects of run-on water and sediment on the erosion process and to find control strategies to minimize the impact of run-on water.

  5. Recharge and flow processes in a till aquitard

    DEFF Research Database (Denmark)

    Schrøder, Thomas Morville; Høgh Jensen, Karsten; Dahl, Mette

    1999-01-01

    Eastern Denmark is primarily covered by clay till. The transformation of the excess rainfall into laterally diverted groundwater flow, drain flow, stream flow, and recharge to the underlying aquifer is governed by complicatedinterrelated processes. Distributed hydrological models provide a framew......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...... 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...

  6. Simulation on flow process of filtered molten metals

    Institute of Scientific and Technical Information of China (English)

    房文斌; 耿耀宏; 魏尊杰; 安阁英; 叶荣茂

    2002-01-01

    Filtration and flow process of molten metals was analyzed by water simulation experiments. Fluid dynamic phenomena of molten metal cells through a foam ceramic filter was described and calculated by ERGOR equation as well. The results show that the filter is most useful for stable molten metals and the filtered flow is laminar, so that inclusions can be removed more effectively.

  7. 4D flow mri post-processing strategies for neuropathologies

    Science.gov (United States)

    Schrauben, Eric Mathew

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

  8. Information systems for material flow management in construction processes

    Science.gov (United States)

    Mesároš, P.; Mandičák, T.

    2015-01-01

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

  9. Stochastic equations, flows and measure-valued processes

    CERN Document Server

    Dawson, Donald A

    2010-01-01

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

  10. Atomic phase diagram

    Institute of Scientific and Technical Information of China (English)

    LI Shichun

    2004-01-01

    Based on the Thomas-Fermi-Dirac-Cheng model, atomic phase diagram or electron density versus atomic radius diagram describing the interaction properties of atoms of different kinds in equilibrium state is developed. Atomic phase diagram is established based on the two-atoms model. Besides atomic radius, electron density and continuity condition for electron density on interfaces between atoms, the lever law of atomic phase diagram involving other physical parameters is taken into account, such as the binding energy, for the sake of simplicity.

  11. Accurate, reliable control of process gases by mass flow controllers

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, J.; McKnight, T.

    1997-02-01

    The thermal mass flow controller, or MFC, has become an instrument of choice for the monitoring and controlling of process gas flow throughout the materials processing industry. These MFCs are used on CVD processes, etching tools, and furnaces and, within the semiconductor industry, are used on 70% of the processing tools. Reliability and accuracy are major concerns for the users of the MFCs. Calibration and characterization technologies for the development and implementation of mass flow devices are described. A test facility is available to industry and universities to test and develop gas floe sensors and controllers and evaluate their performance related to environmental effects, reliability, reproducibility, and accuracy. Additional work has been conducted in the area of accuracy. A gravimetric calibrator was invented that allows flow sensors to be calibrated in corrosive, reactive gases to an accuracy of 0.3% of reading, at least an order of magnitude better than previously possible. Although MFCs are typically specified with accuracies of 1% of full scale, MFCs may often be implemented with unwarranted confidence due to the conventional use of surrogate gas factors. Surrogate gas factors are corrections applied to process flow indications when an MFC has been calibrated on a laboratory-safe surrogate gas, but is actually used on a toxic, or corrosive process gas. Previous studies have indicated that the use of these factors may cause process flow errors of typically 10%, but possibly as great as 40% of full scale. This paper will present possible sources of error in MFC process gas flow monitoring and control, and will present an overview of corrective measures which may be implemented with MFC use to significantly reduce these sources of error.

  12. Conflict resolution of process modeling based on extended UML diagram reduction%基于扩展UML图化简的过程模型冲突消解

    Institute of Scientific and Technical Information of China (English)

    张婷

    2012-01-01

    The structure verification to find out the conflicts of a process model and to generate resolutions is introduced. As a result, the business process can be ensured while running it. Firstly, a process modeling method based on UML activity graph is presented. Its elements are expanded, so it is fit for complex process modeling. Secondly, a conflict detection method based on UML activity diagram reduction is presented. The method can deal with circulation, overlapping structure of complex process model, and can realize three typical structure conflicts, e.g. Deadlock, lack of synchronization and infinite cycles. Besides, a conflict resolution scheme is presented according to the structure conflicts, it is supposed to give any useful suggestion for process modeling staff to handle conflicts.%为保证业务过程模型的结构正确性,使业务过程可以正常终止,需要进行业务过程模型的结构验证.提出基于扩展UML活动图的建模方法,扩展基本UML活动图的元素,使之适合描述复杂的业务过程;提出了相应的冲突检测方法,可以处理合有循环、重叠结构的复杂过程模型,实现对典型结构冲突(如死锁、同步缺失、活锁)的检测.针对过程模型中的各个冲突提出相应冲突消解策略,便于对过程模型进行修改.

  13. Difference Decision Diagrams

    DEFF Research Database (Denmark)

    Moeller, Jesper; Lichtenberg, Jacob; Andersen, Henrik Reif;

    1999-01-01

    This paper describes a new data structure, difference decision diagrams (DDDs), for representing a Boolean logic over inequalities of the form $x-y......This paper describes a new data structure, difference decision diagrams (DDDs), for representing a Boolean logic over inequalities of the form $x-y...

  14. Environmental Data Flow Six Sigma Process Improvement Savings Overview

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-05-20

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

  15. Numerical simulations of rarefied gas flows in thin film processes

    NARCIS (Netherlands)

    Dorsman, R.

    2007-01-01

    Many processes exist in which a thin film is deposited from the gas phase, e.g. Chemical Vapor Deposition (CVD). These processes are operated at ever decreasing reactor operating pressures and with ever decreasing wafer feature dimensions, reaching into the rarefied flow regime. As numerical simulat

  16. Algorithmic phase diagrams

    Science.gov (United States)

    Hockney, Roger

    1987-01-01

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

  17. Rethinking the process of detrainment: jets in obstructed natural flows

    Science.gov (United States)

    Mossa, Michele; de Serio, Francesca

    2016-12-01

    A thorough understanding of the mixing and diffusion of turbulent jets released in porous obstructions is still lacking in literature. This issue is undoubtedly of interest because it is not strictly limited to vegetated flows, but also includes outflows which come from different sources and which spread among oyster or wind farms, as well as aerial pesticide treatments sprayed onto orchards. The aim of the present research is to analyze this process from a theoretical point of view. Specifically, by examining the entrainment coefficient, it is deduced that the presence of a canopy prevents a momentum jet from having an entrainment process, but rather promotes its detrainment. In nature, detrainment is usually associated with buoyancy-driven flows, such as plumes or density currents flowing in a stratified environment. The present study proves that detrainment occurs also when a momentum-driven jet is issued in a not-stratified obstructed current, such as a vegetated flow.

  18. Modeling of material flow in friction stir welding process

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This paper presents a 3D numerical model to study the material flow in the friction stir welding process. Results indicate that the material in front of the pin moves upwards due to the extrusion of the pin, and then the upward material rotates with the pin. Behind the rotating tool, the material starts to move downwards and to deposit in the wake. This process is the real cause to make friction stir welding process continuing successfully. The tangent movement of the material takes the main contribution to the flow of the material in friction stir welding process. There exists a swirl on the advancing side and with the increase of the translational velocity the inverse flow of the material on the advancing side becomes faster. The shoulder can increase the velocity of material flow in both radial direction and tangent direction near the top surface. The variations of process parameters do have an effect on the velocity field near the pin, especially in the region in which the material flow is faster.

  19. Rotating thermal flows in natural and industrial processes

    CERN Document Server

    Lappa, Marcello

    2012-01-01

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

  20. Modeling Workflow Using UML Activity Diagram

    Institute of Scientific and Technical Information of China (English)

    Wei Yinxing(韦银星); Zhang Shensheng

    2004-01-01

    An enterprise can improve its adaptability in the changing market by means of workflow technologies. In the build time, the main function of Workflow Management System (WFMS) is to model business process. Workflow model is an abstract representation of the real-world business process. The Unified Modeling Language (UML) activity diagram is an important visual process modeling language proposed by the Object Management Group (OMG). The novelty of this paper is representing workflow model by means of UML activity diagram. A translation from UML activity diagram to π-calculus is established. Using π-calculus, the deadlock property of workflow is analyzed.

  1. 一种实用的输电网潮流图自动生成算法%A Practical Automatic Generation Algorithm of Power Flow Diagram

    Institute of Scientific and Technical Information of China (English)

    徐丽燕; 陈文静; 苏运光; 孙云枫

    2015-01-01

    Based on the general characteristics of the electricity transmission grid trend diagram ,this paper comprehensively studies a variety of automatic layout and wiring method ,proposes a practical electricity transmission grid trend chart automatic generation algorithm ,and has set up an experiment to verify its effectiveness.%文章针对输电网潮流图的一般特点,综合研究了多种自动布局与布线方法,提出了一种实用性较强的输电网潮流图自动生成算法,并已通过实验验证其有效性.

  2. Inductively generating Euler diagrams.

    Science.gov (United States)

    Stapleton, Gem; Rodgers, Peter; Howse, John; Zhang, Leishi

    2011-01-01

    Euler diagrams have a wide variety of uses, from information visualization to logical reasoning. In all of their application areas, the ability to automatically layout Euler diagrams brings considerable benefits. In this paper, we present a novel approach to Euler diagram generation. We develop certain graphs associated with Euler diagrams in order to allow curves to be added by finding cycles in these graphs. This permits us to build Euler diagrams inductively, adding one curve at a time. Our technique is adaptable, allowing the easy specification, and enforcement, of sets of well-formedness conditions; we present a series of results that identify properties of cycles that correspond to the well-formedness conditions. This improves upon other contributions toward the automated generation of Euler diagrams which implicitly assume some fixed set of well-formedness conditions must hold. In addition, unlike most of these other generation methods, our technique allows any abstract description to be drawn as an Euler diagram. To establish the utility of the approach, a prototype implementation has been developed.

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

    Energy Technology Data Exchange (ETDEWEB)

    Caballero-Guzman, Alejandro; Sun, Tianyin; Nowack, Bernd, E-mail: nowack@empa.ch

    2015-02-15

    Highlights: • Recycling is one of the likely end-of-life fates of nanoproducts. • We assessed the material flows of four nanomaterials in the Swiss recycling system. • After recycling, most nanomaterials will flow to landfills or incineration plants. • Recycled construction waste, plastics and textiles may contain nanomaterials. - Abstract: The use of engineered nanomaterials (ENMs) in diverse applications has increased during the last years and this will likely continue in the near future. As the number of applications increase, more and more waste with nanomaterials will be generated. A portion of this waste will enter the recycling system, for example, in electronic products, textiles and construction materials. The fate of these materials during and after the waste management and recycling operations is poorly understood. The aim of this work is to model the flows of nano-TiO{sub 2}, nano-ZnO, nano-Ag and CNT in the recycling system in Switzerland. The basis for this study is published information on the ENMs flows on the Swiss system. We developed a method to assess their flow after recycling. To incorporate the uncertainties inherent to the limited information available, we applied a probabilistic material flow analysis approach. The results show that the recycling processes does not result in significant further propagation of nanomaterials into new products. Instead, the largest proportion will flow as waste that can subsequently be properly handled in incineration plants or landfills. Smaller fractions of ENMs will be eliminated or end up in materials that are sent abroad to undergo further recovery processes. Only a reduced amount of ENMs will flow back to the productive process of the economy in a limited number of sectors. Overall, the results suggest that risk assessment during recycling should focus on occupational exposure, release of ENMs in landfills and incineration plants, and toxicity assessment in a small number of recycled inputs.

  4. Free-Body Diagrams: Necessary or Sufficient?

    Science.gov (United States)

    Rosengrant, David; Van Heuvelen, Alan; Etkina, Eugenia

    2005-09-01

    The Rutgers PAER group is working to help students develop various scientific abilities. One of the abilities is to create, understand and learn to use for qualitative reasoning and problem solving different representations of physical processes such as pictorial representations, motion diagrams, free-body diagrams, and energy bar charts. Physics education literature indicates that using multiple representations is beneficial for student understanding of physics ideas and for problem solving. We developed a special approach to construct and utilize free-body diagrams for representing physical phenomena and for problem solving. We will examine whether students draw free-body diagrams in solving problems when they know they will not receive credit for it; the consistency of their use in different conceptual areas; and if students who use free-body diagrams while solving problems in different areas of physics are more successful then those who do not.

  5. Application of visual management flow diagram in management of central sterile supply department%目视流程图解在提高消毒供应室管理中的应用

    Institute of Scientific and Technical Information of China (English)

    赵卫萍; 张红超; 庹琨明; 杨涛; 孟玲; 李环

    2015-01-01

    OBJECTIVE To improve the scientific management of central sterile supply department and work quality through the visual management flow diagram .METHODS The visual flow management team was established to de‐velop the visual flow diagram and organize all the staff to learn the concepts ,requirements ,and contents of the visual management flow diagram ,which was served as one of the onsite management modes and was applied for the management of the instruments ,infection control ,and instrument packages .RESULTS As compared with the qualified rate of the instruments in Jul-Sep ,2013 ,it was increased in Jul-Sep ,2014 .The qualified rate of quali‐ty examination of instruments was 97 .57% in 2013 ,99 .75% in 2014 ;the qualified rate of number of instrument packages was 95 .21% in 2013 ,99 .55% in 2014 ;the qualified rate of infection control was 94 .00% in 2013 , 98 .49% in 2014 ;the qualified rate of timely supply of instruments was 95 .80% in 2013 ,99 .44% in 2014 . CONCLUSIONS The visual flow diagram can achieve significant effect on actual management of the central sterile supply department ,raise the work quality and efficiency of the departments ,and make the work flow of the supply department standardized ,the quality control and teaching training visualized;it is a visualized ,high‐efficiency flow management mode .%目的:通过目视流程图解在消毒供应室中的应用,提高供应室科学化管理水平和工作质量。方法科室成立目视流程管理小组,制作目视流程图解,组织全科人员学习目视管理流程图解的概念、要求和内容,将其作为现场管理的模式之一,应用于仪器设备、感染控制、器械包管理。结果器械合格率2013年7-9月与2014年7-9月相比均有提高,其中器械质量检查、器械包装数量、感染控制、器械及时供应等合格率,2013年分别为97.57%、95.21%、94.00%、95.80%;2014年分别为99.75%、99.55%、98

  6. Engineering holographic phase diagrams

    Science.gov (United States)

    Chen, Jiunn-Wei; Dai, Shou-Huang; Maity, Debaprasad; Zhang, Yun-Long

    2016-10-01

    By introducing interacting scalar fields, we tried to engineer physically motivated holographic phase diagrams which may be interesting in the context of various known condensed matter systems. We introduce an additional scalar field in the bulk which provides a tunable parameter in the boundary theory. By exploiting the way the tuning parameter changes the effective masses of the bulk interacting scalar fields, desired phase diagrams can be engineered for the boundary order parameters dual to those scalar fields. We give a few examples of generating phase diagrams with phase boundaries which are strikingly similar to the known quantum phases at low temperature such as the superconducting phases. However, the important difference is that all the phases we have discussed are characterized by neutral order parameters. At the end, we discuss if there exists any emerging scaling symmetry associated with a quantum critical point hidden under the dome in this phase diagram.

  7. Feynman Diagrams for Beginners

    CERN Document Server

    Kumericki, Kresimir

    2016-01-01

    We give a short introduction to Feynman diagrams, with many exercises. Text is targeted at students who had little or no prior exposure to quantum field theory. We present condensed description of single-particle Dirac equation, free quantum fields and construction of Feynman amplitude using Feynman diagrams. As an example, we give a detailed calculation of cross-section for annihilation of electron and positron into a muon pair. We also show how such calculations are done with the aid of computer.

  8. Hyperconcentrated flows as influenced by coupled wind-water processes

    Institute of Scientific and Technical Information of China (English)

    XU; Jiongxin

    2005-01-01

    Using data from more than 40 rivers in the middle Yellow River basin, a study has been made of the influence of coupled wind-water processes on hyperconcentrated flows. A simple "vehicle" model has been proposed to describe hyperconcentrated flows. The liquid phase of two-phase flows is a "vehicle", in which coarse sediment particles are carried as solid-phase. The formation and characteristics of hyperconcentrated flows are closely related with the formation and characteristics of this liquid-phase and solid-phase. Surface materials and geomorphic agents of the middle Yellow River basin form some patterns of combination, which have deep influence on the formation and characteristics of liquid- and solid-phases of hyperconcentrated flows. The combination of high percentages of relatively coarse material with low percentages of fine material appears in the area predominated by the wind process, where the supply of relatively coarse sediment is sufficient, but the supply of relatively coarse sediment is not. The combination of low percentages of relatively coarse material with high percentages of fine material appears in the area predominated by the water process, where the supply of fine sediment is sufficient, but the supply of fine sediment is not. In the area predominated by coupled wind-water processes appears the combination of medium percentages of coarse and fine materials, and thus both coarse and fine sediments are in relatively sufficient supply. The manner in which the mean annual sediment concentrations of liquid- and solid-phases vary with total suspended sediment concentration is different. With the increased total suspended sediment concentration, mean annual sediment concentration of liquid-phase increased to a limit and then remained constant; however, mean annual sediment concentrations of solid-phase increased continuously. Thus, the magnitude of total suspended sediment concentration depends on the supply conditions of relatively coarse sediment

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

    Science.gov (United States)

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

    2015-02-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    J.E. Houseworth

    2001-04-10

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

  11. On-line sample processing methods in flow analysis

    DEFF Research Database (Denmark)

    Miró, Manuel; Hansen, Elo Harald

    2008-01-01

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

  12. Stage line diagram: an age-conditional reference diagram for tracking development.

    NARCIS (Netherlands)

    Van Buuren, S.; Ooms, J.C.L.

    2009-01-01

    This paper presents a method for calculating stage line diagrams, a novel type of reference diagram useful for tracking developmental processes over time. Potential fields of applications include: dentistry (tooth eruption), oncology (tumor grading, cancer staging), virology (HIV infection and disea

  13. Numerical simulation for thermal flow filling process of casting

    Institute of Scientific and Technical Information of China (English)

    CHEN Ye; ZHAO Yu-hong; HOU Hua

    2006-01-01

    The solution algorithm (SOLA) method was used to solve the velocity and pressure field of the thermal flow filling process, and the volume of fluid (VOF) method for the free surface problem. Since the "donor-acceptor" rule often results in the free interface vague, the explicit difference method was adopted, and a method describing the free surface state at 0<F<1 was proposed to deal with this problem. In order to raise the computation efficiency, such algorithms were investigated and invalidated as: 1) internal and external area separation simplification algorithm; 2) the reducing necessary search area method. With the improved algorithms, the filling processes of the valve cover castings with gravity cast and an up cylinder block casting with low-pressure cast were simulated, the simulation results are believable and the computation efficiency is greatly improved. The SOLA-VOF model and its difference method for thermal fluid flow filling process were introduced.

  14. Sustaining processes from recurrent flows in body-forced turbulence

    CERN Document Server

    Lucas, Dan

    2016-01-01

    By extracting unstable invariant solutions directly from body-forced three-dimensional turbulence, we study the dynamical processes at play when the forcing is large scale and either unidirectional in the momentum or the vorticity equations. In the former case, the dynamical processes familiar from recent work on linearly-stable shear flows - variously called the Self-Sustaining Process (Waleffe 1997) or Vortex-Wave Interaction (Hall & Smith 1991; Hall & Sherwin 2010) - are important even when the base flow is linearly unstable. In the latter case, where the forcing drives Taylor-Green vortices, a number of mechanisms are observed from the various types of periodic orbits isolated. In particular, two different transient growth mechanisms are discussed to explain the more complex states found.

  15. Numerical investigations on dynamic process of muzzle flow

    Institute of Scientific and Technical Information of China (English)

    JIANG Xiao-hai; FAN Bao-chun; LI Hong-zhi

    2008-01-01

    The integrative process of a quiescent projectile accelerated by high-pressure gas to shoot out at a supersonic speed and beyond the range of a precursor flow field Was simulated numerically.The calculation was based on ALE equations and a second-order precision Roe method that adopted chimera grids and a dynamic mesh.From the predicted results,the coupling and interaction among the precursor flow field,propellant gas flow field and high-speed projectile were discussed in detail.The shock-vortex interaction,shockwave reflection,shock-projectile interaction with shock diffraction,and shock focus were clearly demonstrated to explain the effect on the acceleration of the projectile.

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

    Directory of Open Access Journals (Sweden)

    E. García-Ladona

    2010-05-01

    Full Text Available Nonlinear phenomena are essential ingredients in many oceanic and atmospheric processes, and successful understanding of them benefits from multidisciplinary collaboration between oceanographers, meteorologists, physicists and mathematicians. The present Special Issue on "Nonlinear Processes in Oceanic and Atmospheric Flows" contains selected contributions from attendants to the workshop which, in the above spirit, was held in Castro Urdiales, Spain, in July 2008. Here we summarize the Special Issue contributions, which include papers on the characterization of ocean transport in the Lagrangian and in the Eulerian frameworks, generation and variability of jets and waves, interactions of fluid flow with plankton dynamics or heavy drops, scaling in meteorological fields, and statistical properties of El Niño Southern Oscillation.

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

    CERN Document Server

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

    2010-01-01

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

  18. Analysis on contact and flow features in CMP process

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chaohui; LUO Jianbin; LIU Jinquan; DU Yongping

    2006-01-01

    Contact pressure and flow features of chemical mechanical polishing/planarization (CMP) process were analyzed, taking advantage of the one-dimensional contact model of two layers and considering slurry flows. In this model, deformations of the bulk pad substrate and the asperities were considered. The deformations of the bulk pad substrate and the asperity layer, as well as the contact pressure and fluid pressure, were revealed with numerical methods. Numerical simulation results show a counterintuitive phenomenon: a diverging clearance is formed in the leading region of the wafer and thereby it gives rise to a suction pressure (subambient pressure). A high stress concentration is presented at the wafer edge and thereby over polishing can be introduced. The research provides some theoretical explanations for these two fundamental features of usual CMP processes.

  19. Processes of Turbulent Liquid Flows in Pipelines and Channels

    Directory of Open Access Journals (Sweden)

    R. I. Yesman

    2011-01-01

    Full Text Available The paper proposes a methodology for an analysis and calculation of processes pertaining to turbulent liquid flows in pipes and channels. Various modes of liquid motion in pipelines of thermal power devices and equipment have been considered in the paper.The presented dependences can be used while making practical calculations of losses due to friction in case of transportation of various energy carriers.

  20. Phase diagram distortion from traffic parameter averaging.

    NARCIS (Netherlands)

    Stipdonk, H. Toorenburg, J. van & Postema, M.

    2010-01-01

    Motorway traffic congestion is a major bottleneck for economic growth. Therefore, research of traffic behaviour is carried out in many countries. Although well describing the undersaturated free flow phase as an almost straight line in a (k,q)-phase diagram, congested traffic observations and theori

  1. Phase diagram of crushed powders

    Science.gov (United States)

    Bodard, Sébastien; Jalbaud, Olivier; Saurel, Richard; Burtschell, Yves; Lapebie, Emmanuel

    2016-12-01

    Compression of monodisperse powder samples in quasistatic conditions is addressed in a pressure range such that particles fragmentation occurs while the solid remains incompressible (typical pressure range of 1-300 MPa for glass powders). For a granular bed made of particles of given size, the existence of three stages is observed during compression and crush up. First, classical compression occurs and the pressure of the granular bed increases along a characteristic curve as the volume decreases. Then, a critical pressure is reached for which fragmentation begins. During the fragmentation process, the granular pressure stays constant in a given volume range. At the end of this second stage, 20%-50% of initial grains are reduced to finer particles, depending on the initial size. Then the compression undergoes the third stage and the pressure increases along another characteristic curve, in the absence of extra fragmentation. The present paper analyses the analogies between the phase transition in liquid-vapour systems and powder compression with crush-up. Fragmentation diagram for a soda lime glass is determined by experimental means. The analogues of the saturation pressure and latent heat of phase change are determined. Two thermodynamic models are then examined to represent the crush-up diagram. The first one uses piecewise functions while the second one is of van der Waals type. Both equations of state relate granular pressure, solid volume fraction, and initial particle diameter. The piecewise functions approach provides reasonable representations of the phase diagram while the van der Waals one fails.

  2. Sulfur Flow Analysis for New Generation Steel Manufacturing Process

    Institute of Scientific and Technical Information of China (English)

    HU Chang-qing; ZHANG Chun-xia; HAN Xiao-wei; YIN Rui-yu

    2008-01-01

    Sulfur flow for new generation steel manufacturing process is analyzed by the method of material flow analysis,and measures for SO2 emission reduction are put forward as assessment and target intervention of the results.The results of sulfur flow analysis indicate that 90% of sulfur comes from fuels.Sulfur finally discharges from the steel manufacturing route in various steps,and the main point is BF and BOF slag desulfurization.In sintering process,the sulfur is removed by gasification,and sintering process is the main source of SO2 emission.The sulfur content of coke oven gas (COG) is an important factor affecting SO2 emission.Therefore,SO2 emission reduction should be started from the optimization and integration of steel manufacturing route,sulfur burden should be reduced through energy saving and consumption reduction,and the sulfur content of fuel should be controlled.At the same time,BF and BOF slag desulfurization should be optimized further and coke oven gas and sintering exhausted gas desulfurization should be adopted for SO2 emission reduction and reuse of resource,to achieve harmonic coordination of economic,social,and environmental effects for sustainable development.

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

    DEFF Research Database (Denmark)

    Friis, Alan; Jensen, Bo Boye Busk

    2002-01-01

    Computational fluid dynamics (CFD) has been applied to investigate the design of closed process equipment with respect to cleanability. The CFD simulations were validated using the standardized cleaning test proposed by the European Hygienic Engineering and Design Group. CFD has been proven...... as a tool which can be used by manufacturers to facilitate their equipment design for high hygienic standards before constructing any prototypes. The study of hydrodynamic cleanability of closed processing equipment was discussed based on modelling the flow in a valve house, an up-stand and various...

  4. Process Improvements to Reform Patient Flow in the Emergency Department.

    Science.gov (United States)

    Whatley, Shawn D; Leung, Alexander K; Duic, Marko

    2016-01-01

    Emergency departments (ED) function to diagnose, stabilize, manage and dispose patients as efficiently as possible. Although problems may be suspected at triage, ED physician input is required at each step of the patient journey through the ED, from diagnosis to disposition. If we want timely diagnosis, appropriate treatment and great outcomes, then ED processes should connect patients and physicians as quickly as possible. This article discusses the key concepts of ED patient flow, value and efficiency. Based on these fundamentals, it describes the significant impact of ED process improvements implemented on measures of ED efficiency at a large community ED in Ontario, Canada.

  5. Detection and quantification of flow consistency in business process models

    DEFF Research Database (Denmark)

    Burattin, Andrea; Bernstein, Vered; Neurauter, Manuel

    2017-01-01

    Business process models abstract complex business processes by representing them as graphical models. Their layout, as determined by the modeler, may have an effect when these models are used. However, this effect is currently not fully understood. In order to systematically study this effect......, a basic set of measurable key visual features is proposed, depicting the layout properties that are meaningful to the human user. The aim of this research is thus twofold: first, to empirically identify key visual features of business process models which are perceived as meaningful to the user and second......, to show how such features can be quantified into computational metrics, which are applicable to business process models. We focus on one particular feature, consistency of flow direction, and show the challenges that arise when transforming it into a precise metric. We propose three different metrics...

  6. Compressing Binary Decision Diagrams

    DEFF Research Database (Denmark)

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

    2008-01-01

    The paper introduces a new technique for compressing Binary Decision Diagrams in those cases where random access is not required. Using this technique, compression and decompression can be done in linear time in the size of the BDD and compression will in many cases reduce the size of the BDD to 1...

  7. Compressing Binary Decision Diagrams

    DEFF Research Database (Denmark)

    Rune Hansen, Esben; Srinivasa Rao, S.; Tiedemann, Peter

    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...

  8. On Argument and Diagrams.

    Science.gov (United States)

    Kneupper, Charles W.

    1978-01-01

    Responds to Charles Willard's recommendations (in an article in "Communication Monographs," November 1976) that argument be viewed as an attempt to establish formal relationships among symbolic structures. Demonstrates flaws in this redefinition and shows argument diagrams to be theoretically and practically justifiable. (JMF)

  9. Equational binary decision diagrams

    NARCIS (Netherlands)

    Groote, J.F.; Pol, J.C. van de

    2000-01-01

    We incorporate equations in binary decision diagrams (BDD). The resulting objects are called EQ-BDDs. A straightforward notion of ordered EQ-BDDs (EQ-OBDD) is defined, and it is proved that each EQ-BDD is logically equivalent to an EQ-OBDD. Moreover, on EQ-OBDDs satisfiability and tautology checkin

  10. Mantle flow in subduction systems: The mantle wedge flow field and implications for wedge processes

    Science.gov (United States)

    Long, Maureen D.; Wirth, Erin A.

    2013-02-01

    The mantle wedge above subducting slabs is associated with many important processes, including the transport of melt and volatiles. Our understanding of mantle wedge dynamics is incomplete, as the mantle flow field above subducting slabs remains poorly understood. Because seismic anisotropy is a consequence of deformation, measurements of shear wave splitting can constrain the geometry of mantle flow. In order to identify processes that make first-order contributions to the pattern of wedge flow, we have compiled a data set of local S splitting measurements from mantle wedges worldwide. There is a large amount of variability in splitting parameters, with average delay times ranging from ~0.1 to 0.3 s up to ~1.0-1.5 s and large variations in fast directions. We tested for relationships between splitting parameters and a variety of parameters related to subduction processes. We also explicitly tested the predictions made by 10 different models that have been proposed to explain splitting patterns in the mantle wedge. We find that no simple model can explain all of the trends observed in the global data set. Mantle wedge flow is likely controlled by a combination of downdip motion of the slab, trench migration, ambient mantle flow, small-scale convection, proximity to slab edges, and slab morphology, with the relative contributions of these in any given subduction system controlled by the subduction kinematics and mantle rheology. There is also a likely contribution from B-type olivine and/or serpentinite fabric in many subduction zones, governed by the local thermal structure and volatile distribution.

  11. The Formal Semantics of an UML Activity Diagram

    Institute of Scientific and Technical Information of China (English)

    梁义芝; 王延章; 刘云飞

    2004-01-01

    Due to lack of strictly defined formal semantics, an UML activity diagram is unsuitable for the tasks of formal analysis, verification and assertion on the system it describes. In this paper, Petri net is used to define the formal semantics of an UML activity diagram containing object flow states, laying a foundation for the precise description and analysis of a workflow system.

  12. Controlling a Linear Process in Turbulent Channel Flow

    Science.gov (United States)

    Lim, Junwoo; Kim, John

    1999-11-01

    Recent studies have shown that controllers developed based on a linear system theory work surprisingly well in reducing the viscous drag in turbulent boundary layers, suggesting that the essential dynamics of near-wall turbulence may well be approximated by the linearized model. Of particular interest is the linear process due to the coupling term between the wall-normal velocity and wall-normal vorticity terms in the linearized Navier-Stokes (N-S) equations, which enhances non-normality of the linearized system. This linear process is investigated through numerical simulations of a turbulent channel flow. It is shown that the linear coupling term plays an important role in fully turbulent -- and hence, nonlinear -- flows. Near-wall turbulence is shown to decay in the absence of the linear coupling term. The fact that the coupling term plays an essential role in maintaining near-wall turbulence suggests that an effective control algorithm for the drag reduction in turbulent flows should be aimed at reducing the effect of the coupling term in the wall region. Designing a control algorithm that directly accounts for the coupling term in a cost to be minimized will be discussed.

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

    OpenAIRE

    Cavazzini, G.; A. Dazin; Pavesi, G; Dupont, P; G. Bois

    2012-01-01

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

  14. Analysis of stochastic characteristics of the Benue River flow process

    Institute of Scientific and Technical Information of China (English)

    Martins Y.OTACHE; Mohammad BAKIR; LI Zhijia

    2008-01-01

    Stochastic characteristics of the Benue River streamflow process are examined under conditions of data austerity.The streamflow process is investigated for trend,non-stationarity and seasonality for a time period of 26 years.Results of trend analyses with Mann-Kendall test show that there is no trend in the annual mean discharges.Monthly flow series examined with seasonal Kendall test indicate the presence of positive change in the trend for some months,especially the months of August,January,and February.For the stationarity test,daily and monthly flow series appear to be stationary whereas at 1%,5%,and 10% significant levels,the stationarity alternative hypothesis is rejected for the annual flow series.Though monthly flow appears to be stationary going by this test,because of high seasonality,it could be said to exhibit periodic stationarity based on the seasonality analysis.The following conclusions are drawn:(1) There is seasonality in both the mean and variance with unimodal distribution.(2) Days with high mean also have high variance.(3) Skewness coefficients for the months within the dry season period are greater than those of the wet season period,and seasonal autocorrelations for streamflow during dry season are generally larger than those of the wet season.Precisely,they are significantly different for most of the months.(4) The autocorrelation functions estimated "over time" are greater in the absolute value for data that have not been deseasonalised but were initially normalised by logarithmic transformation only,while autocorrelation functions for i=1,2,…,365 estimated "over realisations" have their coefficients significantly different from other coefficients.

  15. Design flow for implementing image processing in FPGAs

    Science.gov (United States)

    Trakalo, M.; Giles, G.

    2007-04-01

    A design flow for implementing a dynamic gamma algorithm in an FPGA is described. Real-time video processing makes enormous demands on processing resources. An FPGA solution offers some advantages over commercial video chip and DSP implementation alternatives. The traditional approach to FPGA development involves a system engineer designing, modeling and verifying an algorithm and writing a specification. A hardware engineer uses the specification as a basis for coding in VHDL and testing the algorithm in the FPGA with supporting electronics. This process is work intensive and the verification of the image processing algorithm executing on the FPGA does not occur until late in the program. The described design process allows the system engineer to design and verify a true VHDL version of the algorithm, executing in an FPGA. This process yields reduced risk and development time. The process is achieved by using Xilinx System Generator in conjunction with Simulink® from The MathWorks. System Generator is a tool that bridges the gap between the high level modeling environment and the digital world of the FPGA. System Generator is used to develop the dynamic gamma algorithm for the contrast enhancement of a candidate display product. The results of this effort are to increase the dynamic range of the displayed video, resulting in a more useful image for the user.

  16. Phase diagram of a single lane roundabout

    Science.gov (United States)

    Echab, H.; Lakouari, N.; Ez-Zahraouy, H.; Benyoussef, A.

    2016-03-01

    Using the cellular automata model, we numerically study the traffic dynamic in a single lane roundabout system of four entry/exit points. The boundaries are controlled by the injecting rates α1, α2 and the extracting rate β. Both the system with and without Splitter Islands of width Lsp are considered. The phase diagram in the (α1 , β) space and its variation with the roundabout size, Pagg (i.e. the probability of aggressive entry), and Pexit (i.e. the probability of preferential exit) are constructed. The results show that the phase diagram in both cases consists of three phases: free flow, congested and jammed. However, as Lsp increases the free flow phase enlarges while the congested and jammed ones shrink. On the other hand, the short sized roundabout shows better performance in the free flow phase while the large one is more optimal in the congested phase. The density profiles are also investigated.

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

    DEFF Research Database (Denmark)

    Jabbari, Masoud; Hattel, Jesper Henri

    2011-01-01

    The flow behavior of the fluid in the tape casting process is analyzed. A simple geometry is assumed for running the numerical calculations in ANSYS Fluent and the main parameters are expressed in non-dimensional form. The effect of different values for substrate velocity and pressure force...... 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....

  18. Boolean Expression Diagrams

    DEFF Research Database (Denmark)

    Andersen, Henrik Reif; Hulgaard, Henrik

    2002-01-01

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

  19. Boolean Expression Diagrams

    DEFF Research Database (Denmark)

    Andersen, Henrik Reif; Hulgaard, Henrik

    1997-01-01

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

  20. Design and Realization of Numerical Control Ladder Diagram Edition Software

    Institute of Scientific and Technical Information of China (English)

    ZHAO Haixin; MO Yimin; PAN Yunping

    2006-01-01

    The thesis is directed by the idea of oriented- object. Considering the basic functions that NC system Ladder Diagram editor should provide, and through theoretical research and practice, the thesis developed a set of NC system Ladder Diagram editor which can form a Ladder Diagram editor based on vector plotting, intelligently compiling, simulation. This system uses the ladder diagram symbol to express operational order and use the chart symbol series-parallel connection and the position order to express the logical relations between the operational orders, divide the ladder diagram into four parts: the stave, the line, the row and the part, uses the standard order vessel list vessel of the standard template stack (STL) to save the data which involved in the design process. This system can write PLC program by ladder diagram language and is easy to use. The compilation and simulation for PLC diagram have been achieved. It greatly improves the work-efficiency.

  1. Technology Logic Diagrams

    Energy Technology Data Exchange (ETDEWEB)

    Rudin, M.J. [Univ. of Nevada, Las Vegas NV (United States); O`Brien, M.C. [Univ. of Arizona, Tucson, AZ (United States)

    1995-04-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-12-01

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

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

    Science.gov (United States)

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

    2013-04-01

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

  4. The Massive Thermal Basketball Diagram

    CERN Document Server

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

    2000-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    P. Persoff

    2005-08-04

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

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

    Directory of Open Access Journals (Sweden)

    Emma F. van Bussel

    2013-06-01

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

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

    Directory of Open Access Journals (Sweden)

    Emma F. van Bussel

    2013-06-01

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

  8. Does the butterfly diagram indicate asolar flux-transport dynamo?

    CERN Document Server

    Schüssler, M

    2004-01-01

    We address the question whether the properties of the observed latitude-time diagram of sunspot occurence (the butterfly diagram) provide evidence for the operation of a flux-transport dynamo, which explains the migration of the sunspot zones and the period of the solar cycle in terms of a deep equatorward meridional flow. We show that the properties of the butterfly diagram are equally well reproduced by a conventional dynamo model with migrating dynamo waves, but without transport of magnetic flux by a flow. These properties seem to be generic for an oscillatory and migratory field of dipole parity and thus do not permit an observational distinction between different dynamo approaches.

  9. Hyporheic flow and transport processes: mechanisms, models, and biogeochemical implications

    Science.gov (United States)

    Boano, Fulvio; Harvey, Judson W.; Marion, Andrea; Packman, Aaron I.; Revelli, Roberto; Ridolfi, Luca; Anders, Wörman

    2014-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    E.L. Hardin

    2000-07-17

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

  11. Knot probabilities in random diagrams

    Science.gov (United States)

    Cantarella, Jason; Chapman, Harrison; Mastin, Matt

    2016-10-01

    We consider a natural model of random knotting—choose a knot diagram at random from the finite set of diagrams with n crossings. We tabulate diagrams with 10 and fewer crossings and classify the diagrams by knot type, allowing us to compute exact probabilities for knots in this model. As expected, most diagrams with 10 and fewer crossings are unknots (about 78% of the roughly 1.6 billion 10 crossing diagrams). For these crossing numbers, the unknot fraction is mostly explained by the prevalence of ‘tree-like’ diagrams which are unknots for any assignment of over/under information at crossings. The data shows a roughly linear relationship between the log of knot type probability and the log of the frequency rank of the knot type, analogous to Zipf’s law for word frequency. The complete tabulation and all knot frequencies are included as supplementary data.

  12. Collective neurodynamics: Phase diagram

    OpenAIRE

    Ovchinnikov, Igor V.; Li, Wenyuan; Schwartz, Robert N.; Hudson, Andrew E.; Meier, Karlheinz; Wang, Kang L.

    2016-01-01

    Here, we conceptualize the phase diagram of collective short-term bio-chemo-electric component of neurodynamics (S-ND) on the parameter space of externally, e.g., pharmacologically, controllable single-neuron parameters such as the resting potential and/or firing threshold, repolarization time, etc. This concept may become a useful tool for the systematization of knowledge in anesthesiology and provide a fruitful venue for future studies of the high-level S-ND functionalities such as short-te...

  13. Dissipation process of binary mixture gas in thermally relativistic flow

    CERN Document Server

    Yano, Ryosuke

    2016-01-01

    In this paper, we discuss dissipation process of the binary mixture gas in the thermally relativistic flow \\textcolor{red}{by focusing on the characteristics of the diffusion flux}. As an analytical object, we consider the relativistic rarefied-shock layer problem around the triangle prism. Numerical results of the diffusion flux are compared with the Navier-Stokes-Fourier (NSF) order approximation of the diffusion flux, which is calculated using the diffusion and thermal-diffusion coefficients by Kox \\textit{et al}. [Physica A, 84, 1, pp.165-174 (1976)]. In the case of the uniform flow with the small Lorentz contraction, the diffusion flux, which is obtained by calculating the relativistic Boltzmann equation, is roughly approximated by the NSF order approximation inside the shock wave, whereas the diffusion flux in the vicinity of the wall is markedly different from the NSF order approximation. The magnitude of the diffusion flux, which is obtained by calculating the relativistic Boltzmann equation, is simil...

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

    Science.gov (United States)

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

    2015-06-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    K. Economy

    2004-11-16

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

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

    Energy Technology Data Exchange (ETDEWEB)

    S. Kuzio

    2005-08-20

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

  17. Handling geophysical flows: Numerical modelling using Graphical Processing Units

    Science.gov (United States)

    Garcia-Navarro, Pilar; Lacasta, Asier; Juez, Carmelo; Morales-Hernandez, Mario

    2016-04-01

    Computational tools may help engineers in the assessment of sediment transport during the decision-making processes. The main requirements are that the numerical results have to be accurate and simulation models must be fast. The present work is based on the 2D shallow water equations in combination with the 2D Exner equation [1]. The resulting numerical model accuracy was already discussed in previous work. Regarding the speed of the computation, the Exner equation slows down the already costly 2D shallow water model as the number of variables to solve is increased and the numerical stability is more restrictive. On the other hand, the movement of poorly sorted material over steep areas constitutes a hazardous environmental problem. Computational tools help in the predictions of such landslides [2]. In order to overcome this problem, this work proposes the use of Graphical Processing Units (GPUs) for decreasing significantly the simulation time [3, 4]. The numerical scheme implemented in GPU is based on a finite volume scheme. The mathematical model and the numerical implementation are compared against experimental and field data. In addition, the computational times obtained with the Graphical Hardware technology are compared against Single-Core (sequential) and Multi-Core (parallel) CPU implementations. References [Juez et al.(2014)] Juez, C., Murillo, J., & Garca-Navarro, P. (2014) A 2D weakly-coupled and efficient numerical model for transient shallow flow and movable bed. Advances in Water Resources. 71 93-109. [Juez et al.(2013)] Juez, C., Murillo, J., & Garca-Navarro, P. (2013) . 2D simulation of granular flow over irregular steep slopes using global and local coordinates. Journal of Computational Physics. 225 166-204. [Lacasta et al.(2014)] Lacasta, A., Morales-Hernndez, M., Murillo, J., & Garca-Navarro, P. (2014) An optimized GPU implementation of a 2D free surface simulation model on unstructured meshes Advances in Engineering Software. 78 1-15. [Lacasta

  18. Qualitative Assessment of Flow and Transport Mechanisms in Bioremediation Processes

    Science.gov (United States)

    Terry, N.; Hou, Z.

    2008-12-01

    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.

  19. Energy Tracking Diagrams

    Science.gov (United States)

    Scherr, Rachel E.; Harrer, Benedikt W.; Close, Hunter G.; Daane, Abigail R.; DeWater, Lezlie S.; Robertson, Amy D.; Seeley, Lane; Vokos, Stamatis

    2016-02-01

    Energy is a crosscutting concept in science and features prominently in national science education documents. In the Next Generation Science Standards, the primary conceptual learning goal is for learners to conserve energy as they track the transfers and transformations of energy within, into, or out of the system of interest in complex physical processes. As part of tracking energy transfers among objects, learners should (i) distinguish energy from matter, including recognizing that energy flow does not uniformly align with the movement of matter, and should (ii) identify specific mechanisms by which energy is transferred among objects, such as mechanical work and thermal conduction. As part of tracking energy transformations within objects, learners should (iii) associate specific forms with specific models and indicators (e.g., kinetic energy with speed and/or coordinated motion of molecules, thermal energy with random molecular motion and/or temperature) and (iv) identify specific mechanisms by which energy is converted from one form to another, such as incandescence and metabolism. Eventually, we may hope for learners to be able to optimize systems to maximize some energy transfers and transformations and minimize others, subject to constraints based in both imputed mechanism (e.g., objects must have motion energy in order for gravitational energy to change) and the second law of thermodynamics (e.g., heating is irreversible). We hypothesize that a subsequent goal of energy learning—innovating to meet socially relevant needs—depends crucially on the extent to which these goals have been met.

  20. Eigenanalysis of a neural network for optic flow processing

    Science.gov (United States)

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

    2008-01-01

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

  1. Peripheral processing facilitates optic flow-based depth perception

    Directory of Open Access Journals (Sweden)

    Jinglin Li

    2016-10-01

    Full Text Available Flying insects, such as flies or bees, rely on consistent information regarding the depth structure of the environment when performing their flight maneuvers in cluttered natural environments. These behaviors include avoiding collisions, approaching targets or spatial navigation. Insects are thought to obtain depth information visually from the retinal image displacements (`optic flow' during translational ego-motion. Optic flow in the insect visual system is processed by a mechanism that can be modeled by correlation-type elementary motion detectors (EMDs. However, it is still an open question how spatial information can be extracted reliably from the responses of the highly contrast- and pattern-dependent EMD responses, especially if the vast range of light intensities encountered in natural environments is taken into account. This question will be addressed here by systematically modeling the peripheral visual system of flies, including various adaptive mechanisms. Different model variants of the peripheral visual system were stimulated with image sequences that mimic the panoramic visual input during translational ego-motion in various natural environments, and the resulting peripheral signals were fed into an array of EMDs. We characterized the influence of each peripheral computational unit on the representation of spatial information in the EMD responses. Our model simulations reveal that information about the overall light level needs to be eliminated from the EMD input as is accomplished under light-adapted conditions in the insect peripheral visual system. The response characteristics of large monopolar cells resemble that of a band-pass filter, which reduces the contrast dependency of EMDs strongly, effectively enhancing the representation of the nearness of objects and, especially, of their contours. We furthermore show that local brightness adaptation of photoreceptors allows for spatial vision under a wide range of dynamic light

  2. Coded ultrasound for blood flow estimation using subband processing

    DEFF Research Database (Denmark)

    Gran, Fredrik; Udesen, Jesper; Nielsen, Michael bachmann

    2007-01-01

    This paper further investigates the use of coded excitation for blood flow estimation in medical ultrasound. Traditional autocorrelation estimators use narrow-band excitation signals to provide sufficient signal-to-noise-ratio (SNR) and velocity estimation performance. In this paper, broadband...... was carried out using an experimental ultrasound scanner and a commercial linear array 7 MHz transducer. A circulating flow rig was scanned with a beam-to-flow angle of 60 degrees. The flow in the rig was laminar and had a parabolic flow-profile with a peak velocity of 0.09 m/s. The mean relative standard...

  3. VisFlow - Web-based Visualization Framework for Tabular Data with a Subset Flow Model.

    Science.gov (United States)

    Yu, Bowen; Silva, Claudio T

    2017-01-01

    Data flow systems allow the user to design a flow diagram that specifies the relations between system components which process, filter or visually present the data. Visualization systems may benefit from user-defined data flows as an analysis typically consists of rendering multiple plots on demand and performing different types of interactive queries across coordinated views. In this paper, we propose VisFlow, a web-based visualization framework for tabular data that employs a specific type of data flow model called the subset flow model. VisFlow focuses on interactive queries within the data flow, overcoming the limitation of interactivity from past computational data flow systems. In particular, VisFlow applies embedded visualizations and supports interactive selections, brushing and linking within a visualization-oriented data flow. The model requires all data transmitted by the flow to be a data item subset (i.e. groups of table rows) of some original input table, so that rendering properties can be assigned to the subset unambiguously for tracking and comparison. VisFlow features the analysis flexibility of a flow diagram, and at the same time reduces the diagram complexity and improves usability. We demonstrate the capability of VisFlow on two case studies with domain experts on real-world datasets showing that VisFlow is capable of accomplishing a considerable set of visualization and analysis tasks. The VisFlow system is available as open source on GitHub.

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

    Directory of Open Access Journals (Sweden)

    Mohammed Khennich

    2014-05-01

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

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

    Science.gov (United States)

    Jian, Yu-Cin; Wu, Chao-Jung

    2015-02-01

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

  6. Averaging processes in granular flows driven by gravity

    Science.gov (United States)

    Rossi, Giulia; Armanini, Aronne

    2016-04-01

    One of the more promising theoretical frames to analyse the two-phase granular flows is offered by the similarity of their rheology with the kinetic theory of gases [1]. Granular flows can be considered a macroscopic equivalent of the molecular case: the collisions among molecules are compared to the collisions among grains at a macroscopic scale [2,3]. However there are important statistical differences in dealing with the two applications. In the two-phase fluid mechanics, there are two main types of average: the phasic average and the mass weighed average [4]. The kinetic theories assume that the size of atoms is so small, that the number of molecules in a control volume is infinite. With this assumption, the concentration (number of particles n) doesn't change during the averaging process and the two definitions of average coincide. This hypothesis is no more true in granular flows: contrary to gases, the dimension of a single particle becomes comparable to that of the control volume. For this reason, in a single realization the number of grain is constant and the two averages coincide; on the contrary, for more than one realization, n is no more constant and the two types of average lead to different results. Therefore, the ensamble average used in the standard kinetic theory (which usually is the phasic average) is suitable for the single realization, but not for several realization, as already pointed out in [5,6]. In the literature, three main length scales have been identified [7]: the smallest is the particles size, the intermediate consists in the local averaging (in order to describe some instability phenomena or secondary circulation) and the largest arises from phenomena such as large eddies in turbulence. Our aim is to solve the intermediate scale, by applying the mass weighted average, when dealing with more than one realizations. This statistical approach leads to additional diffusive terms in the continuity equation: starting from experimental

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

    Science.gov (United States)

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

    1972-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Yorstos, Yannis C.

    2003-03-19

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

  9. Coded Ultrasound for Blood Flow Estimation Using Subband Processing

    DEFF Research Database (Denmark)

    Gran, Fredrik; Udesen, Jesper; Nielsen, Michael Bachamnn

    2008-01-01

    This paper investigates the use of coded excitation for blood flow estimation in medical ultrasound. Traditional autocorrelation estimators use narrow-band excitation signals to provide sufficient signal-to-noise-ratio (SNR) and velocity estimation performance. In this paper, broadband coded...... for velocity estimation is compared with a conventional approach transmitting a narrow-band pulse. The study was carried out using an experimental ultrasound scanner and a commercial linear array 7 MHz transducer. A circulating flow rig was scanned with a beam-to-flow angle of 60°. The flow in the rig...

  10. Advanced Information Processing System (AIPS) proof-of-concept system functional design I/O network system services

    Science.gov (United States)

    1985-01-01

    The function design of the Input/Output (I/O) services for the Advanced Information Processing System (AIPS) proof of concept system is described. The data flow diagrams, which show the functional processes in I/O services and the data that flows among them, are contained. A complete list of the data identified on the data flow diagrams and in the process descriptions are provided.

  11. A pseudo-haptic knot diagram interface

    Science.gov (United States)

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

    2011-01-01

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

  12. Diagonal Slices of 3D Young Diagrams in the Approach of Maya Diagrams

    Science.gov (United States)

    Cai, Li-Qiang; Wang, Li-Fang; Wu, Ke; Yang, Jie

    2014-09-01

    According to the correspondence between 2D Young diagrams and Maya diagrams and the relation between 2D and 3D Young diagrams, we construct 3D Young diagrams in the approach of Maya diagrams. Moreover, we formulate the generating function of 3D Young diagrams, which is the MacMahon function in terms of Maya diagrams.

  13. Diagrams and Proofs in Analysis

    DEFF Research Database (Denmark)

    Carter, Jessica M H Grund

    2010-01-01

    The article discusses the role of diagrams in mathematical reasoning based on a case study in analysis.   In the presented example certain combinatorial expressions were first found by using diagrams. In the published proofs the pictures are replaced by reasoning about permutation groups...

  14. Flamelet Regime Diagram for Turbulent Combustion Simulations

    Science.gov (United States)

    Chan, Wai Lee; Ihme, Matthias; Kolla, Hemanth; Chen, Jacqueline

    2016-11-01

    The flamelet model has been widely used in numerical combustion investigations, particularly for the closure of large-eddy simulations (LES) of turbulent reacting flows. In most cases, the simulation results demonstrated good agreements with their experimental counterparts. However, a systematic analysis of the flamelet model's applicability, as well as its potential limitations, is seldom conducted, and the model performance is usually based only on a-posteriori comparisons. The objective of this work is to derive a metric that can formally quantify the suitability of the flamelet model in different flame configurations. For this purpose, a flamelet regime diagram has been developed and studied in the context of direct numerical simulations (DNS) of a turbulent lifted jet flame. The implementation of the regime diagram in LES has been investigated through explicit filtering of the DNS results.

  15. Large eddy simulations of turbulent flows on graphics processing units: Application to film-cooling flows

    Science.gov (United States)

    Shinn, Aaron F.

    Computational Fluid Dynamics (CFD) simulations can be very computationally expensive, especially for Large Eddy Simulations (LES) and Direct Numerical Simulations (DNS) of turbulent ows. In LES the large, energy containing eddies are resolved by the computational mesh, but the smaller (sub-grid) scales are modeled. In DNS, all scales of turbulence are resolved, including the smallest dissipative (Kolmogorov) scales. Clusters of CPUs have been the standard approach for such simulations, but an emerging approach is the use of Graphics Processing Units (GPUs), which deliver impressive computing performance compared to CPUs. Recently there has been great interest in the scientific computing community to use GPUs for general-purpose computation (such as the numerical solution of PDEs) rather than graphics rendering. To explore the use of GPUs for CFD simulations, an incompressible Navier-Stokes solver was developed for a GPU. This solver is capable of simulating unsteady laminar flows or performing a LES or DNS of turbulent ows. The Navier-Stokes equations are solved via a fractional-step method and are spatially discretized using the finite volume method on a Cartesian mesh. An immersed boundary method based on a ghost cell treatment was developed to handle flow past complex geometries. The implementation of these numerical methods had to suit the architecture of the GPU, which is designed for massive multithreading. The details of this implementation will be described, along with strategies for performance optimization. Validation of the GPU-based solver was performed for fundamental bench-mark problems, and a performance assessment indicated that the solver was over an order-of-magnitude faster compared to a CPU. The GPU-based Navier-Stokes solver was used to study film-cooling flows via Large Eddy Simulation. In modern gas turbine engines, the film-cooling method is used to protect turbine blades from hot combustion gases. Therefore, understanding the physics of

  16. Model for Understanding Flow Processes and Distribution in Rock Rubble

    Science.gov (United States)

    Green, R. T.; Manepally, C.; Fedors, R.; Gwo, J.

    2006-12-01

    Recent studies of the potential high-level nuclear waste repository at Yucca Mountain, Nevada, suggest that degradation of emplacement drifts may be caused by either persistent stresses induced by thermal decay of the spent nuclear fuel disposed in the drifts or seismic ground motion. Of significant interest to the performance of the repository is how seepage of water onto the engineered barriers in degraded emplacement drifts would be altered by rubble. Difficulty arises because of the uncertainty associated with the heterogeneity of the natural system complicated by the unknown fragment size and distribution of the rock rubble. A prototype experiment was designed to understand the processes that govern the convergence and divergence of flow in the rubble. This effort is expected to provide additional realism in the corresponding process models and performance assessment of the repository, and to help evaluate the chemistry of water contacting the waste as well as conditions affecting waste package corrosion in the presence of rubble. The rubble sample for the experiment was collected from the lower lithophysal unit of the Topopah Spring (Tptpll) unit in the Enhanced Characterization of the Repository Block Cross Drift and is used as an approximate analog. Most of the potential repository is planned to be built in the Tptpll unit. Sample fragment size varied from 1.0 mm [0.04 in] to 15 cm [6 in]. Ongoing experiments use either a single or multiple sources of infiltration at the top to simulate conditions that could exist in a degraded drift. Seepage is evaluated for variable infiltration rates, rubble particle size distribution, and rubble layering. Comparison of test results with previous bench-scale tests performed on smaller-sized fragments and different geological media will be presented. This paper is an independent product of CNWRA and does not necessarily reflect the view or regulatory position of NRC. The NRC staff views expressed herein are preliminary

  17. Quantitative investigation of the transition process in Taylor-Couette flow

    Energy Technology Data Exchange (ETDEWEB)

    Tu, Xin Cheng; Kim, Hyoung Bum Kim [Gyeongsang National University, Jinju (Korea, Republic of); Liu, Dong [Jiangsu University, Zhenjiang (China)

    2013-02-15

    The transition process from circular Couette flow to Taylor vortex flow regime was experimentally investigated by measuring the instantaneous velocity vector fields at the annular gap flow region between two concentric cylinders. The proper orthogonal decomposition method, vorticity calculation, and frequency analysis were applied in order to analyze the instantaneous velocity fields to identify the flow characteristics during the transition process. From the results, the kinetic energy and corresponding reconstructed velocity fields were able to detect the onset of the transition process and the alternation of the flow structure. The intermittency and oscillation of the vortex flows during the transition process were also revealed from the analysis of the instantaneous velocity fields. The results can be a measure of identifying the critical Reynolds number of the Taylor-Couette flow from a velocity measurement method.

  18. Analysis by Fish Bone Diagram on Human Resources Flow in Community Health Service Institutions in China%我国社区卫生人力流动影响因素鱼骨图分析

    Institute of Scientific and Technical Information of China (English)

    张强; 吴少玮; 方鹏骞

    2012-01-01

    Objective: Analyzing and classifying the factors which affect the human resources' flow, then provide some suggestions to steady the human resources. Methods: By literature analysis, collecting the literature about human resources flow and analyzing the factor of human resources' flow in community health service institutions by fish bone diagram. Results: The factors which affect the stability of human resources in community health service institution could be divided into social factors, organizational factors and personal factors. Conclusion: Effects of the human resources's flow in community health service institutions:social factors, government investment for community health service institutions was not full, security system was not perfect; organizational factors, such as incentive management system, promotion system are not perfect; personal factors such as age, gender, profession, education, job title and so on. Suggestions: In order to steady the human resources in community health service institution, increase the reasonable input to community health service; give the right to community health service institutions for choosing the right person to work; raise the income level; establish a reasonable system of personnel training and a rational system for health staffs title promotion; implement the flexible management to the staff in community health service institutions.%目的:通过对影响社区卫生人力流动的影响因素进行分析,提出稳定社区卫生人力的建议.方法:通过个人访谈和文献查阅收集资料,运用鱼骨图分析法,对于我国社区卫生人力资源流动的影响因素进行分析.结果:影响社区卫生人力资源流动的影响因素可以分为社会因素、组织因素和个人因素3部分.结论:影响我国社区人力资源流动的影响因素有以下几个方面:社会因素方面,政府投入不足,保障制度不健全;机构层面,管理制度如激励机制、晋升制度不健全;

  19. Treatment of volatile organic contaminants in a vertical flow filter: Relevance of different removal processes

    NARCIS (Netherlands)

    De Biase, C.; Reger, D.; Schmidt, A.; Jechalke, S.; Reiche, N.; Martínez-Lavanchy, P.M.; Rosell, M.; Van Afferden, M.; Maier, U.; Oswald, S.E.; Thullner, M.

    2011-01-01

    Vertical flow filters and vertical flow constructed wetlands are established wastewater treatment systems and have also been proposed for the treatment of contaminated groundwater. This study investigates the removal processes of volatile organic compounds in a pilot-scale vertical flow filter. The

  20. Stochastic Modelling of Shiroro River Stream flow Process

    Directory of Open Access Journals (Sweden)

    Musa, J. J

    2013-01-01

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

  1. The Genesis of Feynman Diagrams

    CERN Document Server

    Wuthrich, Adrian

    2011-01-01

    In a detailed reconstruction of the genesis of Feynman diagrams the author reveals that their development was constantly driven by the attempt to resolve fundamental problems concerning the uninterpretable infinities that arose in quantum as well as classical theories of electrodynamic phenomena. Accordingly, as a comparison with the graphical representations that were in use before Feynman diagrams shows, the resulting theory of quantum electrodynamics, featuring Feynman diagrams, differed significantly from earlier versions of the theory in the way in which the relevant phenomena were concep

  2. Scattering equations and Feynman diagrams

    Science.gov (United States)

    Baadsgaard, Christian; Bjerrum-Bohr, N. E. J.; Bourjaily, Jacob L.; Damgaard, Poul H.

    2015-09-01

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

  3. Scattering Equations and Feynman Diagrams

    CERN Document Server

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

    2015-01-01

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

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

    CERN Document Server

    Labbé, Cyril

    2012-01-01

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

  5. Aerodynamic structures and processes in rotationally augmented flow fields

    DEFF Research Database (Denmark)

    Schreck, S.J.; Sørensen, Niels N.; Robinson, M.C.

    2007-01-01

    . Experimental measurements consisted of surface pressure data statistics used to infer sectional boundary layer state and to quantify normal force levels. Computed predictions included high-resolution boundary layer topologies and detailed above-surface flow field structures. This synergy was exploited...... to reliably identify and track pertinent features in the rotating blade boundary layer topology as they evolved in response to varying wind speed. Subsequently, boundary layer state was linked to above-surface flow field structure and used to deduce mechanisms; underlying augmented aerodynamic force...

  6. Particles, Feynman Diagrams and All That

    Science.gov (United States)

    Daniel, Michael

    2006-01-01

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

  7. Flow Field Post Processing via Partial Differential Equations

    NARCIS (Netherlands)

    Preusser, T.; Rumpf, M.; Telea, A.

    2006-01-01

    The visualization of stationary and time-dependent flow is an important and challenging topic in scientific visualization. Its aim is to represent transport phenomena governed by vector fields in an intuitively understandable way. In this paper, we review the use of methods based on partial differen

  8. Coded ultrasound for blood flow estimation using subband processing

    DEFF Research Database (Denmark)

    Gran, F.; Udesen, J.; Jensen, J.A.;

    2008-01-01

    This paper investigates the use of coded excitation for blood flow estimation in medical ultrasound. Traditional autocorrelation estimators use narrow-band excitation signals to provide sufficient signal-to-noise-ratio (SNR) and velocity estimation performance. In this paper, broadband coded sign...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-04-16

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

  10. The Hopf algebra approach to Feynman diagram calculations

    Energy Technology Data Exchange (ETDEWEB)

    Ebrahimi-Fard, Kurusch [Universitaet Bonn, Physikalisches Institut, Nussallee 12, D-53115 Bonn (Germany); Kreimer, Dirk [CNRS-IHES, Le Bois-Marie, 35, Route de Chartres, F-91440 Bures-sur-Yvette (France); Center for Math. Phys., Boston University, MA (United States)

    2005-12-16

    The Hopf algebra structure underlying Feynman diagrams which governs the process of renormalization in perturbative quantum field theory is reviewed. Recent progress is briefly summarized with an emphasis on further directions of research. (topical review)

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

    Directory of Open Access Journals (Sweden)

    David Rosengrant

    2009-06-01

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

  12. Wind Diagrams in Medieval Iceland

    DEFF Research Database (Denmark)

    Kedwards, Dale

    2014-01-01

    This article presents a study of the sole wind diagram that survives from medieval Iceland, preserved in the encyclopaedic miscellany in Copenhagen's Arnamagnæan Institute with the shelf mark AM 732b 4to (c. 1300-25). It examines the wind diagram and its accompanying text, an excerpt on the winds...... from Isidore of Seville's Etymologies. It also examines the perimeter of winds on two medieval Icelandic world maps, and the visual traditions from which they draw....

  13. Bayesian Networks and Influence Diagrams

    DEFF Research Database (Denmark)

    Kjærulff, Uffe Bro; Madsen, Anders Læsø

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

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

    Science.gov (United States)

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

    2015-11-01

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

  15. EFFECTS OF MESON-DECAY DIAGRAMS IN PROTON-PROTON BREMSSTRAHLUNG

    NARCIS (Netherlands)

    DEJONG, F; NAKAYAMA, K

    1995-01-01

    We investigate the effect of meson-decay diagrams on the proton-proton bremsstrahlung process. We explicitly include short-range correlations by calculating single- and double-scattering diagrams using an NN T-matrix interaction. We find that in general these diagrams interfere destructively with th

  16. Simulations of ductile flow in brittle material processing

    Energy Technology Data Exchange (ETDEWEB)

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

    1988-12-01

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

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

    DEFF Research Database (Denmark)

    Andersen, Jens Enevold Thaulov

    2000-01-01

    The technique of Flow-injection Analysis (FIA), now aged 25 years, offers unique analytical methods that are fast, reliable and consuming an absolute minimum of chemicals. These advantages together with its inherent feasibility for automation warrant the future applications of FIA as an attractive...... be used in the resolution of FIA profiles to obtain information about the content of interference’s, in the study of chemical reaction kinetics and to measure absolute concentrations within the FIA-detector cell....

  18. Formation of a Methodological Approach to Evaluating the State of Management of Enterprise Flow Processes

    Directory of Open Access Journals (Sweden)

    Dzobko Iryna P.

    2016-02-01

    Full Text Available The formation of a methodological approach to evaluating management of the state of enterprise flow processes has been considered. Proceeding from the developed and presented in literary sources theoretical propositions on organization of management of enterprise flow processes, the hypothesis of the study is correlation of quantitative and qualitative evaluations of management effectiveness and formation of the integral index on their basis. The article presents stages of implementation of a methodological approach to evaluating the state of management of enterprise flow processes, which implies indicating the components, their characteristics and methods of research. The composition of indicators, on the basis of which it is possible to evaluate effectiveness of management of enterprise flow processes, has been determined. Grouping of such indicators based on the flow nature of enterprise processes has been performed. The grouping of indicators is justified by a pairwise determination of canonical correlations between the selected groups (the obtained high correlation coefficients confirmed the author’s systematization of indicators. It is shown that a specificity of the formation of a methodological approach to evaluating the state of management of enterprise flow processes requires expansion in the direction of aggregation of the results and determination of factors that influence effectiveness of flow processes management. The article carries out such aggregation using the factor analysis. Distribution of a set of objects into different classes according to the results of the cluster analysis has been presented. To obtain an integral estimation of effectiveness of flow processes management, the taxonomic index of a multidimensional object has been built. A peculiarity of the formed methodological approach to evaluating the state of management of enterprise flow processes is in the matrix correlation of integral indicators calculated on

  19. Flagella, flexibility and flow: Physical processes in microbial ecology

    Science.gov (United States)

    Brumley, D. R.; Rusconi, R.; Son, K.; Stocker, R.

    2015-12-01

    How microorganisms interact with their environment and with their conspecifics depends strongly on their mechanical properties, on the hydrodynamic signatures they generate while swimming and on fluid flows in their environment. The rich fluid-structure interaction between flagella - the appendages microorganisms use for propulsion - and the surrounding flow, has broad reaching effects for both eukaryotic and prokaryotic microorganisms. Here, we discuss selected recent advances in our understanding of the physical ecology of microorganisms, which have hinged on the ability to directly interrogate the movement of individual cells and their swimming appendages, in precisely controlled fluid environments, and to image them at appropriately fast timescales. We review how a flagellar buckling instability can unexpectedly serve a fundamental function in the motility of bacteria, we elucidate the role of hydrodynamics and flexibility in the emergent properties of groups of eukaryotic flagella, and we show how fluid flows characteristic of microbial habitats can strongly bias the migration and spatial distribution of bacteria. The topics covered here are illustrative of the potential inherent in the adoption of experimental methods and conceptual frameworks from physics in understanding the lives of microorganisms.

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

    Science.gov (United States)

    Hessel, Volker; Kralisch, Dana; Kockmann, Norbert; Noël, Timothy; Wang, Qi

    2013-05-01

    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.

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

    Science.gov (United States)

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

    2006-01-01

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

  2. Microreactors with integrated UV/Vis spectroscopic detection for online process analysis under segmented flow.

    Science.gov (United States)

    Yue, Jun; Falke, Floris H; Schouten, Jaap C; Nijhuis, T Alexander

    2013-12-21

    Combining reaction and detection in multiphase microfluidic flow is becoming increasingly important for accelerating process development in microreactors. We report the coupling of UV/Vis spectroscopy with microreactors for online process analysis under segmented flow conditions. Two integration schemes are presented: one uses a cross-type flow-through cell subsequent to a capillary microreactor for detection in the transmission mode; the other uses embedded waveguides on a microfluidic chip for detection in the evanescent wave field. Model experiments reveal the capabilities of the integrated systems in real-time concentration measurements and segmented flow characterization. The application of such integration for process analysis during gold nanoparticle synthesis is demonstrated, showing its great potential in process monitoring in microreactors operated under segmented flow.

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

    Science.gov (United States)

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

    2012-01-01

    Basaltic lavas typically form channels or tubes during flow emplacement. However, the importance of sheet flow in the development of basalt ic terrains received recognition over the last 15 years. George Walke r?s research on the 1859 Mauna Loa Flow was published posthumously in 2009. In this paper he discusses the concept of endogenous growth, or inflation, for the distal portion of this otherwise channeldominated lava flow. We used this work as a guide when visiting the 1859 flow to help us better interpret the inflation history of the McCartys flow field in NM. Both well preserved flows display similar clues about the process of inflation. The McCartys lava flow field is among the you ngest (approx.3000 yrs) basaltic lava flows in the continental United States. It was emplaced over slopes of crust or sa gging along fractures that enable gas release. It is not clear which of these processes is responsible for polygonal terrains, and it is po ssible that one explanation is not the sole cause of this morphology between all inflated flows. Often, these smooth surfaces within an inflated sheet display lineated surfaces and occasional squeeze-ups alon g swale contacts. We interpret the lineations to preserve original fl ow direction and have begun mapping these orientations to better interpret the emplacement history. At the scale of 10s to 100s of meters t he flow comprises multiple topographic plateaus and depressions. Some depressions display level floors with surfaces as described above, while some are bowl shaped with floors covered in broken lava slabs. Th e boundaries between plateaus and depressions are also typically smoo th, grooved surfaces that have been tilted to angles sometimes approaching vertical. The upper margin of these tilted surfaces displays lar ge cracks, sometimes containing squeeze-ups. The bottom boundary with smooth floored depressions typically shows embayment by younger lavas. It appears that this style of terrain represents the

  4. Elektrokemiske Processer

    DEFF Research Database (Denmark)

    Bech-Nielsen, Gregers

    1997-01-01

    Electrochemical processes in: Power sources, Electrosynthesis, Corrosion.Pourbaix-diagrams.Decontamination of industrial waste water for heavy metals.......Electrochemical processes in: Power sources, Electrosynthesis, Corrosion.Pourbaix-diagrams.Decontamination of industrial waste water for heavy metals....

  5. Fluid flow and solute segregation in EFG crystal growth process

    Science.gov (United States)

    Bunoiu, O.; Nicoara, I.; Santailler, J. L.; Duffar, T.

    2005-02-01

    The influence of the die geometry and various growth conditions on the fluid flow and on the solute distribution in EFG method has been studied using numerical simulation. The commercial FIDAP software has been used in order to solve the momentum and mass transfer equations in the capillary channel and in the melt meniscus. Two types of shaper design are studied and the results are in good agreement with the void distribution observed in rod-shaped sapphire crystals grown by the EFG method in the various configurations.

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

    DEFF Research Database (Denmark)

    Lind, Morten

    1982-01-01

    of complex systems. A model of a nuclear power plant (PWR) is presented in the paper for illustration. Due to the consistency of the method, multilevel flow models provide specifications of plant goals and functions and may be used as a basis for design of computer-based support systems for the plant...... operator. Plant control requirements can be derived from the models and due to independence of the actual controller implementation the method may be used as a basis for design of control strategies and for the allocation of control tasks to the computer and the plant operator....

  7. Synthesis of a parallel data stream processor from data flow process networks

    NARCIS (Netherlands)

    Zissulescu-Ianculescu, Claudiu

    2008-01-01

    In this talk, we address the problem of synthesizing Process Network specifications to FPGA execution platforms. The process networks we consider are special cases of Kahn Process Networks. We call them COMPAAN Data Flow Process Networks (CDFPN) because they are provided by a translator called the C

  8. Dynamic evolution process of turbulent channel flow after opposition control

    Science.gov (United States)

    Ge, Mingwei; Tian, De; Yongqian, Liu

    2017-02-01

    Dynamic evolution of turbulent channel flow after application of opposition control (OC), together with the mechanism of drag reduction, is studied through direct numerical simulation (DNS). In the simulation, the pressure gradient is kept constant, and the flow rate increases due to drag reduction. In the transport of mean kinetic energy (MKE), one part of the energy from the external pressure is dissipated by the mean shear, and the other part is transported to the turbulent kinetic energy (TKE) through a TKE production term (TKP). It is found that the increase of MKE is mainly induced by the reduction of TKP that is directly affected by OC. Further analysis shows that the suppression of the redistribution term of TKE in the wall normal direction plays a key role in drag reduction, which represses the wall normal velocity fluctuation and then reduces TKP through the attenuation of its main production term. When OC is suddenly applied, an acute imbalance of energy in space is induced by the wall blowing and suction. Both the skin-friction and TKP terms exhibit a transient growth in the initial phase of OC, which can be attributed to the local effect of and in the viscous sublayer. Project supported by the National Natural Science Foundation of China (Grant No. 11402088 and Grant No. 51376062) , State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources (Grant No. LAPS15005), and ‘the Fundamental Research Funds for the Central Universities’ (Grant No.2014MS33).

  9. Perfect orderings on Bratteli diagrams

    CERN Document Server

    Bezuglyi, Sergey; Yassawi, Reem

    2012-01-01

    Given a Bratteli diagram B, we study the set O(B) of all possible orderings w on a Bratteli diagram B and its subset P(B) consisting of `perfect' orderings that produce Bratteli-Vershik dynamical systems (Vershik maps). We give necessary and sufficient conditions for w to be perfect. On the other hand, a wide class of non-simple Bratteli diagrams that do not admit Vershik maps is explicitly described. In the case of finite rank Bratteli diagrams, we show that the existence of perfect orderings with a prescribed number of extreme paths affects significantly the values of the entries of the incidence matrices and the structure of the diagram B. Endowing the set O(B) with product measure, we prove that there is some j such that almost all orderings on B have j maximal and minimal paths, and that if j is strictly greater than the number of minimal components that B has, then almost all orderings are imperfect.

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

    Science.gov (United States)

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

    2009-04-01

    The general processes associated with the formation and activity of ephemeral boccas in lava flow fields are well documented (e.g. Pinkerton & Sparks 1976; Polacci & Papale 1997). The importance of studying such behaviour is illustrated by observations of the emplacement of a basaltic andesite flow at Parícutin during the 1940s. Following a pause in advance of one month, this 8 km long flow was reactivated by the resumption of supply from the vent, which forced the rapid drainage of stagnant material in the flow front region. The material extruded during drainage was in a highly plastic state (Krauskopf 1948), and its displacement allowed hot fluid lava from the vent to be transported in a tube to the original flow front, from where it covered an area of 350,000 m2 in one night (Luhr & Simkin 1993). Determining when a flow has stopped advancing, and cannot be drained in such a manner, is therefore highly important in hazard assessment and flow modelling, and our ability to do this may be improved through the examination of relatively small-scale secondary extrusions and boccas. The 2001 flank eruption of Mt. Etna, Sicily, resulted in the emplacement of a 7 km long compound `a`ā flow field over a period of 23 days. During emplacement, many ephemeral boccas were observed in the flow field, which were active for between two and at least nine days. The longer-lived examples initially fed well-established flows that channelled fresh material from the main vent. With time, as activity waned, the nature of the extruded material changed. The latest stages of development of all boccas involved the very slow extrusion of material that was either draining from higher parts of the flow or being forced out of the flow interior as changing local flow conditions pressurised parts of the flow that had been stagnant for some time. Here we describe this late-stage activity of the ephemeral boccas, which resulted in the formation of ‘squeeze-ups' of lava with a markedly different

  11. Improving modeling with layered UML diagrams

    DEFF Research Database (Denmark)

    Störrle, Harald

    2013-01-01

    Layered diagrams are diagrams whose elements are organized into sets of layers. Layered diagrams are routinely used in many branches of engineering, except Software Engineering. In this paper, we propose to add layered diagrams to UML modeling tools, and elaborate the concept by exploring usage...

  12. Modeling and flow analysis of pure nylon polymer for injection molding process

    Science.gov (United States)

    Nuruzzaman, D. M.; Kusaseh, N.; Basri, S.; Oumer, A. N.; Hamedon, Z.

    2016-02-01

    In the production of complex plastic parts, injection molding is one of the most popular industrial processes. This paper addresses the modeling and analysis of the flow process of the nylon (polyamide) polymer for injection molding process. To determine the best molding conditions, a series of simulations are carried out using Autodesk Moldflow Insight software and the processing parameters are adjusted. This mold filling commercial software simulates the cavity filling pattern along with temperature and pressure distributions in the mold cavity. In the modeling, during the plastics flow inside the mold cavity, different flow parameters such as fill time, pressure, temperature, shear rate and warp at different locations in the cavity are analyzed. Overall, this Moldflow is able to perform a relatively sophisticated analysis of the flow process of pure nylon. Thus the prediction of the filling of a mold cavity is very important and it becomes useful before a nylon plastic part to be manufactured.

  13. Dynamic Simulations of Realistic Upper-Ocean Flow Processes to Support Measurement and Data Analysis

    Science.gov (United States)

    2015-09-30

    the high-momentum flows near the surface into the lower-momentum region in the deeper water . Beneath the surface divergence zone...physics based wind force modeling for oceanic flows ; investigate the impact of spatial and temporal variations of wind forcing on waves, currents, and...processes in the flow , and model their dependence on environmental conditions. APPROACH Our project builds on a suite of

  14. Nonabelian cut diagrams and their applications

    CERN Document Server

    Lam, C S

    1996-01-01

    A new kind of cut diagram is introduced to sum Feynman diagrams with nonabelian vertices. Unlike the Cutkosky diagrams which compute the discontinuity of single Feynman diagrams, the nonabelian cut diagrams represent a resummation of both the real and the imaginary parts of Feynman diagrams related by permutations. Several applications of the technique are reported, including a resolution of the apparent inconsistency of the baryon problem in large-N_c QCD, a simplified calculation of high-energy low-order QCD diagrams, and progress made with this technique on the unitarization of the BFKL equation.

  15. Visualizing spacetimes via embedding diagrams

    CERN Document Server

    Hledik, Stanislav; Cipko, Alois

    2016-01-01

    It is hard to imagine curved spacetimes of General Relativity. A simple but powerful way how to achieve this is visualizing them via embedding diagrams of both ordinary geometry and optical reference geometry. They facilitate to gain an intuitive insight into the gravitational field rendered into a curved spacetime, and to assess the influence of parameters like electric charge and spin of a black hole, magnetic field or cosmological constant. Optical reference geometry and related inertial forces and their relationship to embedding diagrams are particularly useful for investigation of test particles motion. Embedding diagrams of static and spherically symmetric, or stationary and axially symmetric black-hole and naked-singularity spacetimes thus present a useful concept for intuitive understanding of these spacetimes' nature. We concentrate on general way of embedding into 3-dimensional Euclidean space, and give a set of illustrative examples.

  16. Multi-currency Influence Diagrams

    DEFF Research Database (Denmark)

    Nielsen, Søren Holbech; Nielsen, Thomas Dyhre; Jensen, Finn V.

    2007-01-01

    When using the influence diagrams framework for solving a decision problem with several different quantitative utilities, the traditional approach has been to convert the utilities into one common currency. This conversion is carried out using a tacit transformation, under the assumption that the......When using the influence diagrams framework for solving a decision problem with several different quantitative utilities, the traditional approach has been to convert the utilities into one common currency. This conversion is carried out using a tacit transformation, under the assumption...... that the converted problem is equivalent to the original one. In this paper we present an extension of the influence diagram framework. The extension allows for these decision problems to be modelled in their original form. We present an algorithm that, given a linear conversion function between the currencies...

  17. A review of concentrated flow erosion processes on rangelands: Fundamental understanding and knowledge gaps

    Directory of Open Access Journals (Sweden)

    Sayjro K. Nouwakpo

    2016-06-01

    Full Text Available Concentrated flow erosion processes are distinguished from splash and sheetflow processes in their enhanced ability to mobilize and transport large amounts of soil, water and dissolved elements. On rangelands, soil, nutrients and water are scarce and only narrow margins of resource losses are tolerable before crossing the sustainability threshold. In these ecosystems, concentrated flow processes are perceived as indicators of degradation and often warrant the implementation of mitigation strategies. Nevertheless, this negative perception of concentrated flow processes may conflict with the need to improve understanding of the role of these transport vessels in redistributing water, soil and nutrients along the rangeland hillslope. Vegetation influences the development and erosion of concentrated flowpaths and has been the primary factor used to control and mitigate erosion on rangelands. At the ecohydrologic level, vegetation and concentrated flow pathways are engaged in a feedback relationship, the understanding of which might help improve rangeland management and restoration strategies. In this paper, we review published literature on experimental and conceptual research pertaining to concentrated flow processes on rangelands to: (1 present the fundamental science underpinning concentrated flow erosion modeling in these landscapes, (2 discuss the influence of vegetation on these erosion processes, (3 evaluate the contribution of concentrated flow erosion to overall sediment budget and (4 identify knowledge gaps.

  18. The Eh-pH Diagram and Its Advances

    Directory of Open Access Journals (Sweden)

    Hsin-Hsiung Huang

    2016-01-01

    Full Text Available Since Pourbaix presented Eh versus pH diagrams in his “Atlas of Electrochemical Equilibria in Aqueous Solution”, diagrams have become extremely popular and are now used in almost every scientific area related to aqueous chemistry. Due to advances in personal computers, such diagrams can now show effects not only of Eh and pH, but also of variables, including ligand(s, temperature and pressure. Examples from various fields are illustrated in this paper. Examples include geochemical formation, corrosion and passivation, precipitation and adsorption for water treatment and leaching and metal recovery for hydrometallurgy. Two basic methods were developed to construct an Eh-pH diagram concerning the ligand component(s. The first method calculates and draws a line between two adjacent species based on their given activities. The second method performs equilibrium calculations over an array of points (500 × 800 or higher are preferred, each representing one Eh and one pH value for the whole system, then combines areas of each dominant species for the diagram. These two methods may produce different diagrams. The fundamental theories, illustrated results, comparison and required conditions behind these two methods are presented and discussed in this paper. The Gibbs phase rule equation for an Eh-pH diagram was derived and verified from actual plots. Besides indicating the stability area of water, an Eh-pH diagram normally shows only half of an overall reaction. However, merging two or more related diagrams together reveals more clearly the possibility of the reactions involved. For instance, leaching of Au with cyanide followed by cementing Au with Zn (Merrill-Crowe process can be illustrated by combining Au-CN and Zn-CN diagrams together. A second example of the galvanic conversion of chalcopyrite can be explained by merging S, Fe–S and Cu–Fe–S diagrams. The calculation of an Eh-pH diagram can be extended easily into another dimension, such

  19. Diagram of Zeolite Crystals

    Science.gov (United States)

    2003-01-01

    The Center for Advanced Microgravity Materials Processing (CAMMP) in Cambridge, MA, a NASA-sponsored Commercial Space Center, is working to improve zeolite materials for storing hydrogen fuel. CAMMP is also applying zeolites to detergents, optical cables, gas and vapor detection for environmental monitoring and control, and chemical production techniques that significantly reduce by-products that are hazardous to the environment. Depicted here is one of the many here complex geometric shapes which make them highly absorbent. Zeolite experiments have also been conducted aboard the International Space Station

  20. PROCESS INTENSIFICATION: MICROWAVE INITIATED REACTIONS USING A CONTINUOUS FLOW REACTOR

    Science.gov (United States)

    The concept of process intensification has been used to develop a continuous narrow channel reactor at Clarkson capable of carrying out reactions under isothermal conditions whilst being exposed to microwave (MW) irradiation thereby providing information on the true effect of mi...

  1. Numerical calculation of flow and heat transfer process in the new-type external combustion swirl-flowing hot stove

    Institute of Scientific and Technical Information of China (English)

    Shuchen Zhang; Hongzhi Guo; Xiangjun Liu; Zhangping Cai; Xiancheng Gao; Sidong Xu

    2003-01-01

    It is clarified that the important method to improve the blast temperature of the small and the middle blast furnaces whose production is about two-thirds of total sum of China from 1000℃ to 1250-1300℃ is to preheat both their combustion-supporting air and coal gas. The air temperature of blast furnaces can be reached to 1250-1300℃ by burning single blast furnace coal gas if high speed burner is applied to blast furnaces and new-type external combustion swirl-flowing hot stove is used to preheat their combustion-supporting air. The computational results of the flow and heat transfer processions in the bot stove prove that the surface of the bed of the thernal storage balls there have not eccentric flow and the flow field and temperature field distribution is even. The computational results of the blast temperature distribution are similar to those determination experiment data. The numerical results also provide references for developing and designing the new-type external combustion swirl-flowing hot stoves.

  2. Identification of vortices in a transonic compressor flow and the stall process

    Institute of Scientific and Technical Information of China (English)

    HUANGXu-dong; CHENHai-xin; FUSong; DavidWisler; AspiWadia; G.ScottMcNulty

    2007-01-01

    A novel vortex identification method for the visualization of the flow field is used for the study of the stall process of a transonic compressor. The parameter η4, which is one of the five invariants formed by the stain rate and vorticity tensors from the theory of modern rational mechanics, is found to have good ability to identify vortex stretching and vortex relaxation/breakdown processes, is introduced here to identify the tip leakage vortices. Compare with former generally used DPH(dynamic pressure head) contour, the new method reveals much more flow details which may advance our understanding of the compressor behaviors. The Vortices details are revealed in both peak efficiency and near stall condition. A possible stall process is also suggested based on the vortices analysis. The tip leakage flow from mid-chord, besides leading edge leakage flow, is also considered to play an important role in the stall process.

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

    Science.gov (United States)

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

    2015-02-02

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Yortsos, Yanis C.

    2002-10-08

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

  5. Model of coupled gas flow and deformation process in heterogeneous coal seams and its application

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chun-hui; ZHAO Quan-sheng; YU Yong-jiang

    2011-01-01

    The heterogeneity of coal was studied by mechanical tests. Probability plots of experimental data show that the mechanical parameters of heterogeneous coal follow a Weibull distribution. Based on elasto-plastic mechanics and gas dynamics, the model of coupled gas flow and deformation process of heterogeneous coal was presented and the effects of heterogeneity of coal on gas flow and failure of coal were investigated. Major findings include: The effect of the heterogeneity of coal on gas flow and mechanical failure of coal can be considered by the model in this paper. Failure of coal has a great effect on gas flow.

  6. Resource Analysis of Cognitive Process Flow Used to Achieve Autonomy

    Science.gov (United States)

    2016-03-01

    the software is fixed (e.g., many FPGA implementations). The structural complexity reflected in the state space is determined by the... reflected in the state-space trajectories that move in multiple state-space dimensions simultaneously. • In synchronous processing the trajectories...important component of the configuration state would be the strengths of synaptic connections between neurons. Figure 7: Decomposition of Internal System

  7. Neuraminidase Ribbon Diagram

    Science.gov (United States)

    2004-01-01

    Ribbons is a program developed at UAB used worldwide to graphically depict complicated protein structures in a simplified format. The program uses sophisticated computer systems to understand the implications of protein structures. The Influenza virus remains a major causative agent for a large number of deaths among the elderly and young children and huge economic losses due to illness. Finding a cure will have a general impact both on the basic research of viral pathologists of fast evolving infectious agents and clinical treatment of influenza virus infection. The reproduction process of all strains of influenza are dependent on the same enzyme neuraminidase. Shown here is a segmented representation of the neuraminidase inhibitor compound sitting inside a cave-like contour of the neuraminidase enzyme surface. This cave-like formation present in every neuraminidase enzyme is the active site crucial to the flu's ability to infect. The space-grown crystals of neuraminidase have provided significant new details about the three-dimensional characteristics of this active site thus allowing researchers to design drugs that fit tighter into the site. Principal Investigator: Dr. Larry DeLucas

  8. The International Space Station Alpha (ISSA) End-to-End On-Orbit Maintenance Process Flow

    Science.gov (United States)

    Zingrebe, Kenneth W., II

    1995-01-01

    As a tool for construction and refinement of the on-orbit maintenance system to sustain the International Space Station Alpha (ISSA), the Mission Operations Directorate (MOD) developed an end to-end on-orbit maintenance process flow. This paper discusses and demonstrates that process flow. This tool is being used by MOD to identify areas which require further work in preparation for MOD's role in the conduct of on-orbit maintenance operations.

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

    CERN Document Server

    Foucart, Clément

    2011-01-01

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

  10. Electrical elementary diagrams and operators

    Energy Technology Data Exchange (ETDEWEB)

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

    2005-07-01

    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)

  11. The diagram for phyllotactic series

    Directory of Open Access Journals (Sweden)

    Joanna Szymanowska-Pułka

    2014-01-01

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

  12. BIHOURLY DIAGRAMS OF FORBUSH DECREASES

    Science.gov (United States)

    Bihourly diagrams were made of Forbush decreases of cosmic ray intensity as observed at Uppsala from 31 Aug 56 to 31 Dec 59, at Kiruna from Nov 56 to 31 Dec 59, and at Murchison Bay from 26 Aug 57 to 30 Apr 59. (Author)

  13. Bayesian Networks and Influence Diagrams

    DEFF Research Database (Denmark)

    Kjærulff, Uffe Bro; Madsen, Anders Læsø

    Bayesian Networks and Influence Diagrams: A Guide to Construction and Analysis, Second Edition, provides a comprehensive guide for practitioners who wish to understand, construct, and analyze intelligent systems for decision support based on probabilistic networks. This new edition contains six new...

  14. Grid diagrams and Khovanov homology

    DEFF Research Database (Denmark)

    Droz, Jean-Marie; Wagner, Emmanuel

    2009-01-01

    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...

  15. Multi-currency Influence Diagrams

    DEFF Research Database (Denmark)

    Nielsen, Søren Holbech; Nielsen, Thomas Dyhre; Jensen, Finn Verner

    2004-01-01

    that the converted problem is equivalent to the original one. In this paper we present an extension of the Influence Diagram framework, which allows for these decision problems to be modelled in their original form. We present an algorithm that, given a conversion function between the currencies, discovers...

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

    Science.gov (United States)

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

    2009-12-01

    The transfer of sediment from steep hillslopes into channels and subsequent mobilization remains a problem with implications for the development of landscapes as well as applications in natural hazards mitigation. The Illgraben catchment in the Swiss Alps is among the most active catchments in Europe, with several 100’000 cubic meters of sediment exported from the catchment (active area debris flows every year, providing an exceptional opportunity to investigate the transfer of sediment from hillslopes to the outlet of the channel at the distal end of the alluvial fan. Thirty-four debris flows or similar torrential flash flood/hyper-concentrated flows have been recorded at the debris flow observation station since the year 2000. Data are available for many flow properties including front velocity (max. 10 m/s) and front flow depth (max. 3.25 m) as well as estimates for debris flow volume (max. 85,000 cubic meters). Flow bulk density data are also available from a large force plate installation for most flows since 2004, permitting estimation of sediment export from the catchment by debris flows. The channel morphology is strongly affected by these events, and debris flows can increase their volume considerably by entraining material from the channel bed. Aerial photography of the initiation area and upper catchment (fall 2007, early summer and fall 2008; fall 2009 is planned) and photogrammetric analyses allow detection of areas of land surface elevation change (deposition or erosion). Strong hillslope channel coupling is expected, with sediment delivery to the steep torrent channels by rockfall and other mass-movement processes. The upper catchment is generally quite active, yet the main sediment source of debris flows varies from event to event In some cases it was possible to identify the movement of small landslides into torrent channels and the subsequent removal by debris flows. In other cases no landslide activity was obvious and the sediment for the

  17. GATE REGULATION SPEED AND TRANSITION PROCESS OF UNSTEADY FLOW IN CHANNEL

    Institute of Scientific and Technical Information of China (English)

    TAN Guang-ming; DING Zhi-liang; WANG Chang-de; YAO Xiong

    2008-01-01

    The operation methods of channel and the speed of gate regulation have great influence on the transformation of flow in water conveyance channels. Based on characteristics method, a 1-D unsteady flow numerical model for gate regulation was established in this study. The process of water flow was simulated under different boundary conditions. The influence of gate regulation speed and channel operation methods on flow transition process was analyzed. The numerical results show that under the same conditions, with increasing regulation speed of the gate, the change rates of discharge and water level increase, while the response time of channel becomes shorter, and ultimately the discharge and water level will transit to the same equilibrium states. Moreover, the flow is easier to reach stable state, if the water level in front of the sluice is kept constant, instead of behind the sluice. This study will be important to the scheme design of automatic operation control in water conveyance channels.

  18. Between Analogue and Digital Diagrams

    Directory of Open Access Journals (Sweden)

    Zoltan Bun

    2012-10-01

    Full Text Available This essay is about the interstitial. About how the diagram, as a method of design, has lead fromthe analogue deconstruction of the eighties to the digital processes of the turn of the millennium.Specifically, the main topic of the text is the interpretation and the critique of folding (as a diagramin the beginning of the nineties. It is necessary then to unfold its relationship with immediatelypreceding and following architectural trends, that is to say we have to look both backwards andforwards by about a decade. The question is the context of folding, the exchange of the analogueworld for the digital. To understand the process it is easier to investigate from the fields of artand culture, rather than from the intentionally perplicated1 thoughts of Gilles Deleuze. Both fieldsare relevant here because they can similarly be used as the yardstick against which the era itselfit measured. The cultural scene of the eighties and nineties, including performing arts, movies,literature and philosophy, is a wide milieu of architecture. Architecture responds parallel to itsera; it reacts to it, and changes with it and within it. Architecture is a medium, it has always beena medium, yet the relations are transformed. That’s not to say that technical progress, for exampleusing CAD-software and CNC-s, has led to the digital thinking of certain movements ofarchitecture, (it is at most an indirect tool. But the ‘up-to-dateness’ of the discipline, however,a kind of non-servile reading of an ‘applied culture’ or ‘used philosophy’2 could be the key.(We might recall here, parenthetically, the fortunes of the artistic in contemporary mass society.The proliferation of museums, the magnification of the figure of the artist, the existence of amassive consumption of printed and televised artistic images, the widespread appetite for informationabout the arts, all reflect, of course, an increasingly leisured society, but also relateprecisely to the fact

  19. Regional Groundwater Processes and Flow Dynamics from Age Tracer Data

    Science.gov (United States)

    Morgenstern, Uwe; Stewart, Mike K.; Matthews, Abby

    2016-04-01

    Age tracers are now used in New Zealand on regional scales for quantifying the impact and lag time of land use and climate change on the quantity and quality of available groundwater resources within the framework of the National Policy Statement for Freshwater Management 2014. Age tracers provide measurable information on the dynamics of groundwater systems and reaction rates (e.g. denitrification), essential for conceptualising the regional groundwater - surface water system and informing the development of land use and groundwater flow and transport models. In the Horizons Region of New Zealand, around 200 wells have tracer data available, including tritium, SF6, CFCs, 2H, 18O, Ar, N2, CH4 and radon. Well depths range from shallower wells in gravel aquifers in the Horowhenua and Tararua districts, and deeper wells in the aquifers between Palmerston North and Wanganui. Most of the groundwater samples around and north of the Manawatu River west of the Tararua ranges are extremely old (>100 years), even from relatively shallow wells, indicating that these groundwaters are relatively disconnected from fresh surface recharge. The groundwater wells in the Horowhenua tap into a considerably younger groundwater reservoir with groundwater mean residence time (MRT) of 10 - 40 years. Groundwater along the eastern side of the Tararua and Ruahine ranges is significantly younger, typically groundwater recharge rates, as deduced from groundwater depth and MRT, are extremely low in the central coastal area, consistent with confined groundwater systems, or with upwelling of old groundwater close to the coast. Very low vertical recharge rates along the Manawatu River west of the Manawatu Gorge indicate upwelling groundwater conditions in this area, implying groundwater discharge into the river is more likely here than loss of river water into the groundwater system. High recharge rates observed at several wells in the Horowhenua area and in the area east of the Tararua and

  20. Biodiesel and FAME synthesis assisted by microwaves: Homogeneous batch and flow processes

    Energy Technology Data Exchange (ETDEWEB)

    J. Hernando; P. Leton; M.P. Matia; J.L. Novella; J. Alvarez-Builla [Universidad de Alcala, Madrid (Spain). Planta Piloto de Quimica Fina

    2007-07-15

    Fatty acids methyl esters (FAME) have been prepared under microwave irradiation, using homogeneous catalysis, either in batch or in a flow system. The quality of the biodiesel obtained has been confirmed by GC analysis of the isolated product. While the initial experiments have been performed in a small scale laboratory batch reactor, the best experiment has been straightforward converted into a stop-flow process, by the use of a microwave flow system. Compared with conventional heating methods, the process using microwaves irradiation proved to be a faster method for alcoholysis of triglycerides with methanol, leading to high yields of FAME. Short communication. 19 refs., 2 tabs.

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

    CERN Document Server

    Brenner, Howard

    1992-01-01

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

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

    Science.gov (United States)

    Sidle, Roy C.

    2015-04-01

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

  3. Kinematical Diagrams for Conical Relativistic Jets

    Indian Academy of Sciences (India)

    Gopal-Krishna; Pronoy Sircar; Samir Dhurde

    2007-03-01

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

  4. Utilization of milli-scale coiled flow inverter in combination with phase separator for continuous flow liquid-liquid extraction processes

    NARCIS (Netherlands)

    Vural Gürsel, Iris; Kurt, Safa Kutup; Aalders, Jasper; Wang, Qi; Noël, Timothy; Nigam, Krishna D P; Kockmann, Norbert; Hessel, Volker

    2016-01-01

    Process-design intensification situated under the umbrella of Novel Process Windows heads for process integration and here most development is needed for flow separators. The vision is to achieve multi-step synthesis in flow on pilot scale. This calls for scale-up of separation units. This study is

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

    CERN Document Server

    Kim, Y

    2002-01-01

    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...

  6. Parallel flow accumulation algorithms for graphical processing units with application to RUSLE model

    Science.gov (United States)

    Sten, Johan; Lilja, Harri; Hyväluoma, Jari; Westerholm, Jan; Aspnäs, Mats

    2016-04-01

    Digital elevation models (DEMs) are widely used in the modeling of surface hydrology, which typically includes the determination of flow directions and flow accumulation. The use of high-resolution DEMs increases the accuracy of flow accumulation computation, but as a drawback, the computational time may become excessively long if large areas are analyzed. In this paper we investigate the use of graphical processing units (GPUs) for efficient flow accumulation calculations. We present two new parallel flow accumulation algorithms based on dependency transfer and topological sorting and compare them to previously published flow transfer and indegree-based algorithms. We benchmark the GPU implementations against industry standards, ArcGIS and SAGA. With the flow-transfer D8 flow routing model and binary input data, a speed up of 19 is achieved compared to ArcGIS and 15 compared to SAGA. We show that on GPUs the topological sort-based flow accumulation algorithm leads on average to a speedup by a factor of 7 over the flow-transfer algorithm. Thus a total speed up of the order of 100 is achieved. We test the algorithms by applying them to the Revised Universal Soil Loss Equation (RUSLE) erosion model. For this purpose we present parallel versions of the slope, LS factor and RUSLE algorithms and show that the RUSLE erosion results for an area of 12 km x 24 km containing 72 million cells can be calculated in less than a second. Since flow accumulation is needed in many hydrological models, the developed algorithms may find use in many other applications than RUSLE modeling. The algorithm based on topological sorting is particularly promising for dynamic hydrological models where flow accumulations are repeatedly computed over an unchanged DEM.

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

    Science.gov (United States)

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

    2014-12-01

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

  8. Wildfire impacts on the processes that generate debris flows in burned watersheds

    Science.gov (United States)

    Parise, M.; Cannon, S.H.

    2012-01-01

    Every year, and in many countries worldwide, wildfires cause significant damage and economic losses due to both the direct effects of the fires and the subsequent accelerated runoff, erosion, and debris flow. Wildfires can have profound effects on the hydrologic response of watersheds by changing the infiltration characteristics and erodibility of the soil, which leads to decreased rainfall infiltration, significantly increased overland flow and runoff in channels, and movement of soil. Debris-flow activity is among the most destructive consequences of these changes, often causing extensive damage to human infrastructure. Data from the Mediterranean area and Western United States of America help identify the primary processes that result in debris flows in recently burned areas. Two primary processes for the initiation of fire-related debris flows have been so far identified: (1) runoff-dominated erosion by surface overland flow; and (2) infiltration-triggered failure and mobilization of a discrete landslide mass. The first process is frequently documented immediately post-fire and leads to the generation of debris flows through progressive bulking of storm runoff with sediment eroded from the hillslopes and channels. As sediment is incorporated into water, runoff can convert to debris flow. The conversion to debris flow may be observed at a position within a drainage network that appears to be controlled by threshold values of upslope contributing area and its gradient. At these locations, sufficient eroded material has been incorporated, relative to the volume of contributing surface runoff, to generate debris flows. Debris flows have also been generated from burned basins in response to increased runoff by water cascading over a steep, bedrock cliff, and incorporating material from readily erodible colluvium or channel bed. Post-fire debris flows have also been generated by infiltration-triggered landslide failures which then mobilize into debris flows. However

  9. Revised state diagram of Laponite dispersions.

    Science.gov (United States)

    Mongondry, Philippe; Tassin, Jean François; Nicolai, Taco

    2005-03-15

    We propose a state diagram of charged disk-like mineral particle (Laponite) dispersions as a function of the Laponite concentration (C) and the concentration of added salt (C(s)), based on simple observation and light-scattering measurements. At low C or high C(s) the dispersions separate into two domains due to sedimentation of Laponite aggregates, while at high C and low C(s) they form homogeneous gels that do not flow upon tube reversal. The aggregation rate and the structure factor of the Laponite dispersions is determined with light scattering as a function of C and C(s). We discuss in detail the controversy on the origin of gelation of Laponite dispersions in the absence of added salt. We argue that aggregation rather than glass formation causes gelation.

  10. Process window diagram of conical cups in hydrodynamic deep drawing assisted by radial pressure%径向压力辅助充液拉深锥形杯的工艺窗口图

    Institute of Scientific and Technical Information of China (English)

    Abbas HASHEMI; Mohammad HOSEINPOUR GOLLO; S. M. Hossein SEYEDKASHI

    2015-01-01

    Major defects in forming of conical cups are wrinkles and rupture. Hydrodynamic deep drawing assisted by radial pressure (HDDRP) is a sheet hydroforming process for production of shell cups in one step. In this work, process window diagrams (PWDs) for Al1050-O, pure copper and DIN 1623 St14 steel are obtained for HDDRP process. The PWD is determined to provide a quick assessment of part producibility for sheet hydroforming process. Finite element method is used for this purpose considering the process parameters including pressure path, and the blank material and its thickness. Numerical results are validated by experiments. It is shown that the sheets with less initial thickness and higher strength show better formability and uniformity of thickness distribution on final product. The results demonstrate that the obtained PWD can predict appropriate forming area and probability of rupture or wrinkling occurrence under different pressure loading paths.%起皱和破裂是锥形杯成形过程中的主要缺陷.径向压力辅助充液拉深是一步成形筒形件的板材液压成形技术.获得了径向压力辅助充液拉深 Al1050-O、纯铜和DIN1623 St14钢板的工艺窗口图.该工艺窗口图可快速评估板材液压成形零件的可制造性.采用有限元方法对径向压力辅助充液拉深进行模拟,并研究压力路径和原始材料及其厚度的影响.通过实验对模拟结果进行验证.结果表明:对于初始厚度较薄和强度较高的板材,其成形性更好,最终产品的的厚度分布也更均匀.所得工艺窗口图可以预测在不同加载路径下合适的加工区间以及破裂或起皱的可能性.

  11. Hero's journey in bifurcation diagram

    Science.gov (United States)

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

    2012-06-01

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

  12. Fast blood flow visualization of high-resolution laser speckle imaging data using graphics processing unit.

    Science.gov (United States)

    Liu, Shusen; Li, Pengcheng; Luo, Qingming

    2008-09-15

    Laser speckle contrast analysis (LASCA) is a non-invasive, full-field optical technique that produces two-dimensional map of blood flow in biological tissue by analyzing speckle images captured by CCD camera. Due to the heavy computation required for speckle contrast analysis, video frame rate visualization of blood flow which is essentially important for medical usage is hardly achieved for the high-resolution image data by using the CPU (Central Processing Unit) of an ordinary PC (Personal Computer). In this paper, we introduced GPU (Graphics Processing Unit) into our data processing framework of laser speckle contrast imaging to achieve fast and high-resolution blood flow visualization on PCs by exploiting the high floating-point processing power of commodity graphics hardware. By using GPU, a 12-60 fold performance enhancement is obtained in comparison to the optimized CPU implementations.

  13. Hubble's diagram and cosmic expansion

    OpenAIRE

    Kirshner, Robert P.

    2003-01-01

    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 velo...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-09-15

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

  15. Scheil-Gulliver Constituent Diagrams

    Science.gov (United States)

    Pelton, Arthur D.; Eriksson, Gunnar; Bale, Christopher W.

    2017-03-01

    During solidification of alloys, conditions often approach those of Scheil-Gulliver cooling in which it is assumed that solid phases, once precipitated, remain unchanged. That is, they no longer react with the liquid or with each other. In the case of equilibrium solidification, equilibrium phase diagrams provide a valuable means of visualizing the effects of composition changes upon the final microstructure. In the present study, we propose for the first time the concept of Scheil-Gulliver constituent diagrams which play the same role as that in the case of Scheil-Gulliver cooling. It is shown how these diagrams can be calculated and plotted by the currently available thermodynamic database computing systems that combine Gibbs energy minimization software with large databases of optimized thermodynamic properties of solutions and compounds. Examples calculated using the FactSage system are presented for the Al-Li and Al-Mg-Zn systems, and for the Au-Bi-Sb-Pb system and its binary and ternary subsystems.

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

    Energy Technology Data Exchange (ETDEWEB)

    Yortsos, Yanis C.

    2001-08-07

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Yortsos, Y.C.

    2001-05-29

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

  18. Wildfire-related debris-flow generation through episodic progressive sediment-bulking processes, western USA

    Science.gov (United States)

    Cannon, S.H.; Gartner, J.E.; Parrett, C.; Parise, M.; ,

    2003-01-01

    Debris-flow initiation processes on hillslopes recently burned by wildfire differ from those generally recognized on unburned, vegetated hillslopes. These differences result from fire-induced changes in the hydrologic response to rainfall events. In this study, detailed field and aerial photographic mapping, observations, and measurements of debris-flow events from three sites in the western U.S. are used to describe and evaluate the process of episodic progressive sediment bulking of storm runoff that leads to the generation of post-wildfire debris flows. Our data demonstrate the effects of material credibility, sediment availability on hillslopes and in channels, the degree of channel confinement, the formation of continuous channel incision, and the upslope contributing area and its gradient on the generation of flows and the magnitude of the response are demonstrated. ?? 2003 Millpress.

  19. Similarity between the Spiral Arms of Galaxy M51 Image and the Interface Curve of Yin-Yang Balance in the Ancient Tai-Chi Diagram

    Institute of Scientific and Technical Information of China (English)

    Sui Lin

    2009-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Holisz-Burzyńska, J.

    2007-01-01

    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.

  1. A new look at φ-pH diagram (Ⅱ) ——All-equilibrium φ-pH diagram for M-ligand-H2O system

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A new viewpoint on metal complex system was proposed on traditional M-ligand-H2O system φ-pH diagrams. Simultaneous equilibrium principle and activity term method were used to plot all-equilibrium φ-pH diagrams for M-ligand-H2O systems based on the thermochemical database developed. The mathematical and computer algorithms were described with the Cu-NH3-H2O system as an example. More quantitative information on real hydrometallurgical processes can be obtained from these diagrams compared with the conventional Pourbaix φ-pH diagram.

  2. 3D visualization of the material flow in friction stir welding process

    Institute of Scientific and Technical Information of China (English)

    Zhao Yanhua; Lin Sanbao; Shen Jiajie; Wu Lin

    2005-01-01

    The material flow in friction stir welded 2014 Al alloy has been investigated using a marker insert technique (MIT). Results of the flow visualization show that the material flow is asymmetrical during the friction stir welding(FSW)process and there are also significant differences in the flow patterns observed on advancing side and retreating side. On advancing side, some material transport forward and some move backward, but on retreating side, material only transport backward. At the top surface of the weld, significant material traasport forward due to the action of the rotating tool shoulder.Combining the data from all the markers, a three-dimensional flow visualization, similar to the 3D image reconstruction technique, was obtained. The three-dimensional plot gives the tendency chart of material flow in friction stir welding process and from the plot it can be seen that there is a vertical, circular motion around the longitudinal axis of the weld. On the advancing side of the weld, the material is pushed downward but on the retreating side, the material is pushed toward the crown of the weld. The net result of the two relative motions in both side of the advancing and the retreating is that a circular motion comes into being. Comparatively, the material flow around the longitudinal axis is a secondary motion.

  3. A finite element modeling on the fluid flow and solidification in a continuous casting process

    Energy Technology Data Exchange (ETDEWEB)

    Kim, T.H.; Kim, D.S. [Hanyang University Graduate School, Seoul (Korea); Choi, H.C. [Agency for Defence Development, Taejon (Korea); Kim, S.W. [Hanyang University, Seoul (Korea); Lee, S.K. [Chung Buk National University, Chungju (Korea)

    1999-07-01

    The coupled turbulent flow and solidification is considered in a typical slab continuous casting process using commercial program FIDAP. Standard {kappa}-{epsilon} turbulence model is modified to decay turbulent viscosity in the mushy zone and laminar viscosity is set to a sufficiently large value at the solid region. This coupled turbulent flow and solidification model also contains thermal contact resistance due to the mold powder and air gap between the strand and mold using an effective thermal conductivity. From the computed flow pattern, the trajectory of inclusion particles was calculated. The comparison between the predicted and experimental solidified shell thickness shows a good agreement. (author). 27 refs., 11 figs., 2 tabs.

  4. A New Method to Track Resin Flow Fronts in Mold Filling Simulation of RTM Process

    Institute of Scientific and Technical Information of China (English)

    Fuhong DAI; Shanyi DU; Boming ZHANG; Dianfu WAN

    2004-01-01

    A new method to track resin flow fronts, referred to as the topological interpolated method (TIM), which is based on filling states and topological relations of adjacent nodes was proposed. An experiment on the mould filling process was conducted. It was compared with exact solutions and the experimental results, and good agreements were observed. Numerical and experimental comparisons with the conventional contour method were also carried out, and it showed that TIM could enhance the local accuracy of flow front solutions with respect to the contour method when merging flow fronts and resin approaching the mold wall were involved.

  5. Empirical analysis of the lane formation process in bidirectional pedestrian flow

    Science.gov (United States)

    Feliciani, Claudio; Nishinari, Katsuhiro

    2016-09-01

    This paper presents an experimental study on pedestrian bidirectional streams and the mechanisms leading to spontaneous lane formation by examining the flow formed by two groups of people walking toward each other in a mock corridor. Flow ratio is changed by changing each group size while maintaining comparable total flow and density. By tracking the trajectories of each pedestrian and analyzing the data obtained, five different phases were recognized as contributing to the transition from unidirectional to bidirectional flow including the spontaneous creation and dissolution of lanes. It has been shown that a statistical treatment is required to understand the fundamental characteristics of pedestrian dynamics and some two-dimensional quantities such as order parameter and rotation range were introduced to allow a more complete analysis. All the quantities observed showed a clear relationship with flow ratio and helped distinguishing between the different characteristic phases of the experiment. Results show that balanced bidirectional flow becomes the most stable configuration after lanes are formed, but the lane creation process requires pedestrians to laterally move to a largest extent compared to low flow-ratio configurations. This finding allows us to understand the reasons why balanced bidirectional flow is efficient at low densities, but quickly leads to deadlock formation at high densities.

  6. Operations space diagram for ECRH and ECCD

    DEFF Research Database (Denmark)

    Bindslev, H.

    2004-01-01

    A Clemmov-Mullaly-Allis (CMA) type diagram, the ECW-CMA diagram, for representing the operational possibilities of electron cyclotron heating and current drive (ECRH/ECCD) systems for fusion plasmas is presented. In this diagram, with normalized density and normalized magnetic field coordinates...

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

    Science.gov (United States)

    Salazar, Daniel; Moore, Bill; Valadez, John

    2012-11-01

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

  8. Confined gravity flow sedimentary process and its impact on the lower continental slope,Niger Delta

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    There is active gravity flow sedimentation on the lower continental slope of Niger Delta. High-resolution 3-D seismic data enable a detailed study on the gravity flow deposition process and its impact. The lower continental slope of Niger Delta is characterized by a stepped complex topography, which resulted from gravity sliding and spreading during Miocene and Pliocene. Two types of accommodations are identified on the slope: ponded accommodation as isolated sub-basins and healed slope accommodation as connected tortuous corridors, where multi-scale submarine fans and submarine channels developed. Gravity flow deposition process is affected by the characteristics of gravity flows and the receiving basin. At the early stage, gravity flow deposition process was dominated by "fill and spill" pattern in the ponded accommodation, whereas it was confined to the healed slope accommodation during the late stage. On the lower continental slope of Niger Delta, complex slope topography controlled the distribution and evolution of the gravity flow, producing complicated gravity depositional patterns.

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

    Directory of Open Access Journals (Sweden)

    Wu Li-Li

    2015-01-01

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

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

    Science.gov (United States)

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

    2009-03-01

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

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Cally Gill

    2013-09-01

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

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

    Science.gov (United States)

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

    2013-01-01

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

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

    Science.gov (United States)

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

    2013-09-18

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

  15. Development of the Hydroecological Integrity Assessment Process for Determining Environmental Flows for New Jersey Streams

    Science.gov (United States)

    Kennen, Jonathan G.; Henriksen, James A.; Nieswand, Steven P.

    2007-01-01

    The natural flow regime paradigm and parallel stream ecological concepts and theories have established the benefits of maintaining or restoring the full range of natural hydrologic variation for physiochemical processes, biodiversity, and the evolutionary potential of aquatic and riparian communities. A synthesis of recent advances in hydroecological research coupled with stream classification has resulted in a new process to determine environmental flows and assess hydrologic alteration. This process has national and international applicability. It allows classification of streams into hydrologic stream classes and identification of a set of non-redundant and ecologically relevant hydrologic indices for 10 critical sub-components of flow. Three computer programs have been developed for implementing the Hydroecological Integrity Assessment Process (HIP): (1) the Hydrologic Indices Tool (HIT), which calculates 171 ecologically relevant hydrologic indices on the basis of daily-flow and peak-flow stream-gage data; (2) the New Jersey Hydrologic Assessment Tool (NJHAT), which can be used to establish a hydrologic baseline period, provide options for setting baseline environmental-flow standards, and compare past and proposed streamflow alterations; and (3) the New Jersey Stream Classification Tool (NJSCT), designed for placing unclassified streams into pre-defined stream classes. Biological and multivariate response models including principal-component, cluster, and discriminant-function analyses aided in the development of software and implementation of the HIP for New Jersey. A pilot effort is currently underway by the New Jersey Department of Environmental Protection in which the HIP is being used to evaluate the effects of past and proposed surface-water use, ground-water extraction, and land-use changes on stream ecosystems while determining the most effective way to integrate the process into ongoing regulatory programs. Ultimately, this scientifically defensible

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

    Science.gov (United States)

    Py, Dominique; Auxepaules, Ludovic; Alonso, Mathilde

    2013-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Antonio A. Romero

    2012-07-01

    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.

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

    DEFF Research Database (Denmark)

    Wildenschild, Dorthe; Hopmans, J.W.; Rivers, M.L.

    2005-01-01

    been of a mostly qualitative nature and no experiments have been presented in the existing literature where a truly quantitative approach to investigating the multiphase flow process has been taken, including a thorough image-processing scheme. The tomographic images presented here show, both...... on observed dynamic effects in the measured pressure-saturation curves; a significantly higher residual and higher capillary pressures were found when the sample was drained fast using a high air-phase pressure. Prior work applying the X-ray microtomography technique to pore-scale multiphase flow problems has...

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

    Energy Technology Data Exchange (ETDEWEB)

    Resnik, Kevin P.; Pennline, Henry W.

    2013-03-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-07-01

    The design of an efficient process flow-sheet requires accurate extraction data for the experimental set-up used. Often this data is provided as equilibrium data. Due to the small hold-up volume compared to the flow rate in centrifugal contactors the time for extraction is often too short to reach equilibrium D-ratios. In this work single stage kinetics experiments have been carried out to investigate the D-ratio dependence of the flow rate and to compare this with equilibrium batch experiments for a SANEX system based on CyMe{sub 4}-BTBP. The first centrifuge experiment was run with spiked solutions while in the second a genuine actinide/lanthanide fraction from a TODGA process was used. Three different flow rates were tested with each set-up. The results show that even with low flow rates, only around 9% of the equilibrium D-ratio (Am) was reached for the extraction in the spiked test and around 16% in the hot test (the difference is due to the size of the centrifuges). In the hot test the lanthanide scrubbing was inefficient whereas in the stripping both the actinides and the lanthanides showed good results. Based on these results improvements of the suggested flow-sheet is discussed. (orig.)

  1. Effects of anthropogenic water regulation and groundwater lateral flow on land processes

    Science.gov (United States)

    Zeng, Yujin; Xie, Zhenghui; Yu, Yan; Liu, Shuang; Wang, Linying; Zou, Jing; Qin, Peihua; Jia, Binghao

    2016-09-01

    Both anthropogenic water regulation and groundwater lateral flow essentially affect groundwater table patterns. Their relationship is close because lateral flow recharges the groundwater depletion cone, which is induced by over-exploitation. In this study, schemes describing groundwater lateral flow and human water regulation were developed and incorporated into the Community Land Model 4.5. To investigate the effects of human water regulation and groundwater lateral flow on land processes as well as the relationship between the two processes, three simulations using the model were conducted for the years 2003-2013 over the Heihe River Basin in northwestern China. Simulations showed that groundwater lateral flow driven by changes in water heads can essentially change the groundwater table pattern with the deeper water table appearing in the hillslope regions and shallower water table appearing in valley bottom regions and plains. Over the last decade, anthropogenic groundwater exploitation deepened the water table by approximately 2 m in the middle reaches of the Heihe River Basin and rapidly reduced the terrestrial water storage, while irrigation increased soil moisture by approximately 0.1 m3 m-3. The water stored in the mainstream of the Heihe River was also reduced by human surface water withdrawal. The latent heat flux was increased by 30 W m-2 over the irrigated region, with an identical decrease in sensible heat flux. The simulated groundwater lateral flow was shown to effectively recharge the groundwater depletion cone caused by over-exploitation. The offset rate is higher in plains than mountainous regions.

  2. Wildfire-related debris-flow initiation processes, Storm King Mountain, Colorado

    Science.gov (United States)

    Cannon, S.H.; Kirkham, R.M.; Parise, M.

    2001-01-01

    A torrential rainstorm on September 1, 1994 at the recently burned hillslopes of Storm King Mountain, CO, resulted in the generation of debris flows from every burned drainage basin. Maps (1:5000 scale) of bedrock and surficial materials and of the debris-flow paths, coupled with a 10-m Digital Elevation Model (DEM) of topography, are used to evaluate the processes that generated fire-related debris flows in this setting. These evaluations form the basis for a descriptive model for fire-related debris-flow initiation. The prominent paths left by the debris flows originated in 0- and 1st-order hollows or channels. Discrete soil-slip scars do not occur at the heads of these paths. Although 58 soil-slip scars were mapped on hillslopes in the burned basins, material derived from these soil slips accounted for only about 7% of the total volume of material deposited at canyon mouths. This fact, combined with observations of significant erosion of hillslope materials, suggests that a runoff-dominated process of progressive sediment entrainment by surface runoff, rather than infiltration-triggered failure of discrete soil slips, was the primary mechanism of debris-flow initiation. A paucity of channel incision, along with observations of extensive hillslope erosion, indicates that a significant proportion of material in the debris flows was derived from the hillslopes, with a smaller contribution from the channels. Because of the importance of runoff-dominated rather than infiltration-dominated processes in the generation of these fire-related debris flows, the runoff-contributing area that extends upslope from the point of debris-flow initiation to the drainage divide, and its gradient, becomes a critical constraint in debris-flow initiation. Slope-area thresholds for fire-related debris-flow initiation from Storm King Mountain are defined by functions of the form Acr(tan ??)3 = S, where Acr is the critical area extending upslope from the initiation location to the

  3. Aerodynamic Study on Supersonic Flows in High-Velocity Oxy-Fuel Thermal Spray Process

    Institute of Scientific and Technical Information of China (English)

    Hiroshi KATANODA; Takeshi MATSUOKA; Seiji KURODA; Jin KAWAKITA; Hirotaka FUKANUMA; Kazuyasu MATSUO

    2005-01-01

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

  4. Penguin-like Diagrams from the Standard Model

    CERN Document Server

    Chia, Swee-Ping

    2015-01-01

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

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

    Science.gov (United States)

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

    2006-01-01

    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

  6. Database design using entity-relationship diagrams

    CERN Document Server

    Bagui, Sikha

    2011-01-01

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

  7. Numerical and Experimental Study of the Bleeder Flow in Autoclave Process

    Science.gov (United States)

    Li, Yanxia; Li, Min; Gu, Yizhuo; Zhang, Zuoguang

    2011-08-01

    In the autoclave process, resin flow is a primary mechanics for the removing of excess resin and voids entrapped in the laminate and obtaining a uniform and void free composite part. A numerical method was developed to simulate the resin flow in the laminate and the bleeder, and the effects of `bleeder flow' on the resin flow and fiber compaction were conducted. At the same time, fiber distribution in the cured laminates was investigated by both experiments and simulations for the CF/Epoxy and CF/BMI composites. The data of the experiments and simulations demonstrated that fibers consolidated and reconsolidated in the laminate and it was impacted by the viscosity and gel time of the resin system. Compared to the post study in which only resin flow in the laminate are considered, these results will deepen the understanding of the consolidation process, resin pressure variation and void control during the autoclave process, which is valuable for the study of the performance of composite parts, provided that fiber distribution does affect some properties of composite material.

  8. Carbonate gravity-flow processes on the Lower Permian slope, northwest Delaware basin

    Energy Technology Data Exchange (ETDEWEB)

    Loucks, R.G.; Brown, A.A.; Achauer, C.W. (ARCO Oil and Gas Co., Plano, TX (United States))

    1991-03-01

    Wolfcampian carbonate gravity-flow deposits accumulated on a low-angle slope in front of a platform of relatively low relief ({approximately}220 m). A 25 m core, located approximately 15 km basinward of the self margin, was examined to determine processes of carbonate deposition in the middle to distal slope environments. The majority of the deposits are cohesive debris-flows composed of clast-supported conglomerates with a calcareous siliciclastic mudstone matrix. Other deposits include high- and low-density turbidites of lime packstones (sand- to boulder-size range), lime grainstones, and siliclastic muddy silstones and suspension deposits of calcareous siliciclastic mudstones. Cohesive debris flows are generally massive and structureless, although several flows show an inverse-graded zone at their base indicating dispersive pressure forces that developed in a traction carpet. Other flows display coarse-tail fining-upward sequences indicating deposition by suspension settling from liquefied flow. At the base of each high-density, gravelly turbidite is one to several inversely graded zones of carbonated clasts indicating a traction carpet zone. These traction carpets are overlain by normal-graded units of shell and clast material. The upper units appear to be deposited directly out of suspension. The low-density turbidites are interpreted to be the residual products of more shelfward-deposited debris flows and high-density turbidity currents. Many of the depositional features described here for carbonate gravity-flow deposits are identical to those in siliclastic deposits, therefore the depositional processes controlling these features are probably similar.

  9. Flow Stress Behavior and Processing Map of Al-Cu-Mg-Ag Alloy during Hot Compression

    Institute of Scientific and Technical Information of China (English)

    YANG Sheng; YI Danqing; ZHANG Hong; YAO Sujuan

    2008-01-01

    The hot deformation behavior of Al-Cu-Mg-Ag was studied by isothermal hot compression tests in the temperature range of 573-773 K and strain rate range of 0.001-1 s-1 on a Gleeble 1500 D thermal mechanical simulator. The results show the flow stress of Al-Cu-Mg-Ag alloy increases with strain rate and decreases after a peak value, indicating dynamic recovery and recrystallization. A hyperbolic sine relationship is found to correlate well the flow stress with the strain rate and temperature, the flow stress equation is estimated to illustrate the relation of strain rate and stress and temperature during high temperature deformation process. The processing maps exhibit two domains as optimum fields for hot deformation at different strains, including the high strain rate domain in 623-773 K and the low strain rate domain in 573-673 K.

  10. Asteroseismology Across the HR Diagram

    Science.gov (United States)

    Thompson, M. J.; Cunha, M. S.; Monteiro, M. J. P. F. G.

    2003-05-01

    Ground-based observations have detected solar-like oscillations on Sun-like stars, and diagnostics similar to those used in helioseismology are now being used to test and constrain the physics and evolutionary state of these stars. Multi-mode oscillations are being observed in an abundance of other stars, including slowly pulsating B stars (SPB stars), delta-Scuti stars, Ap stars and the pulsating white dwarfs. New classes of pulsators continue to be discovered across the Herzsprung-Russell diagram. Yet the chances still to be faced to make asteroseismology across the HR diagram a reality are formidable. Observation, data analysis and theory all pose hard problems to be overcome. This book, reflecting the goal of the meeting, aims to facilitate a cross-fertilisation of ideas and approaches between fields covering different pulsators and with different areas of expertise. The book successfully covers most known types of pulsators, reflecting a highly productive and far reaching interchange of ideas which we believe is conveyed by the papers and posters published, making it a reference for researchers and postgraduate students working on stellar structure and evolution. Link: http://www.wkap.nl/prod/b/1-4020-1173-3

  11. Phase Diagrams of Nuclear Pasta

    Science.gov (United States)

    Caplan, Matthew; Horowitz, Chuck; Berry, Don; da Silva Schneider, Andre

    2016-03-01

    In the inner crust of neutrons stars, where matter is near the saturation density, protons and neutrons arrange themselves into complex structures called nuclear pasta. Early theoretical work predicted a simple graduated hierarchy of pasta phases, consisting of spheres, cylinders, slabs, and uniform matter with voids. Previous work has simulated these phases with a simple classical model and has shown that the formation of these structures is dependent on the temperature, density, and proton fraction. However, previous work only studied a limited range of these parameters due to computational limitations. Thanks to recent advances in computing it is now possible to survey the structure of nuclear pasta for a larger range of parameters. By simulating nuclear pasta with constant temperature and proton fraction in an expanding simulation volume we are able to study the phase transitions in nuclear pasta, and thus produce a set of phase diagrams. We report on these phase diagrams as well as newly identified phases of nuclear pasta and discuss their implications for neutron star observables.

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

    Science.gov (United States)

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

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

    DEFF Research Database (Denmark)

    Hovad, Emil; Larsen, P.; Walther, Jens Honore

    2015-01-01

    The DISAMATIC casting process production of sand moulds is simulated with DEM (discrete element method). The main purpose is to simulate the dynamics of the flow of green sand, during the production of the sand mould with DEM. The sand shot is simulated, which is the first stage of the DISAMATIC...

  14. Toward a Unified Modeling of Learner's Growth Process and Flow Theory

    Science.gov (United States)

    Challco, Geiser C.; Andrade, Fernando R. H.; Borges, Simone S.; Bittencourt, Ig I.; Isotani, Seiji

    2016-01-01

    Flow is the affective state in which a learner is so engaged and involved in an activity that nothing else seems to matter. In this sense, to help students in the skill development and knowledge acquisition (referred to as learners' growth process) under optimal conditions, the instructional designers should create learning scenarios that favor…

  15. Applying Process-Based Models for Subsurface Flow Treatment Wetlands: Recent Developments and Challenges

    Directory of Open Access Journals (Sweden)

    Guenter Langergraber

    2016-12-01

    Full Text Available To date, only few process-based models for subsurface flow treatment wetlands have been developed. For modelling a treatment wetland, these models have to comprise a number of sub-models to describe water flow, pollutant transport, pollutant transformation and degradation, effects of wetland plants, and transport and deposition of suspended particulate matter. The two most advanced models are the HYDRUS Wetland Module and BIO-PORE. These two models are briefly described. This paper shows typical simulation results for vertical flow wetlands and discusses experiences and challenges using process-based wetland models in relation to the sub-models describing the most important wetland processes. It can be demonstrated that existing simulation tools can be applied for simulating processes in treatment wetlands. Most important for achieving a good match between measured and simulated pollutant concentrations is a good calibration of the water flow and transport models. Only after these calibrations have been made and the effect of the influent fractionation on simulation results has been considered, should changing the parameters of the biokinetic models be taken into account. Modelling the effects of wetland plants is possible and has to be considered when important. Up to now, models describing clogging are the least established models among the sub-models required for a complete wetland model and thus further development and research is required.

  16. Experimental investigation and numerical simulation of plastic flow behavior during forward-backward-radial extrusion process

    OpenAIRE

    A. Farhoumand; R. Ebrahimi

    2016-01-01

    Finite element method was employed to investigate the effect of process parameters of plastic deformation behavior in Forward-Backward-Radial Extrusion (FBRE) process. The result of an axisymmetric model shows that the friction between die components and the sample has a substantial effect on the material flow behavior. Although strain heterogeneity index (SHI) slightly decreases with an increase in friction, large portion of the sample experiences significant strain heterogeneity. Increasing...

  17. Turbulent Fluid Flow and Heat Transfer Calculation in Mold Filling and Solidification Processes of Castings

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Based on the time-averaging equations and a modified engineering turbulence model, the mold filling and solidification processes of castings are approximately described. The algorithm for the control equations is briefly introduced, and some problems and improvement methods for the traditional method are also presented. Both calculation and tests proved that, comparing with the laminar fluid flow and heat transfer, the simulation results by using the turbulence model are closer to the real mold filling and solidification processes of castings.

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

    Directory of Open Access Journals (Sweden)

    A. Boisson

    2014-08-01

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

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

    Directory of Open Access Journals (Sweden)

    Cuicui Wang

    2015-01-01

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

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

    Science.gov (United States)

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

    2010-12-01

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

  1. Scale-up from batch to flow-through wet milling process for injectable depot formulation.

    Science.gov (United States)

    Lehocký, Róbert; Pěček, Daniel; Štěpánek, František

    2016-12-01

    Injectable depot formulations are aimed at providing long-term sustained release of a drug into systemic circulation, thus reducing plasma level fluctuations and improving patient compliance. The particle size distribution of the formulation in the form of suspension is a key parameter that controls the release rate. In this work, the process of wet stirred media milling (ball milling) of a poorly water-soluble substance has been investigated with two main aims: (i) to determine the parametric sensitivity of milling kinetics; and (ii) to develop scale-up methodology for process transfer from batch to flow-through arrangement. Ball milling experiments were performed in two types of ball mills, a batch mill with a 30ml maximum working volume, and a flow-through mill with a 250ml maximum working volume. Milling parameters were investigated in detail by methodologies of QbD to map the parametric space. Specifically, the effects of ball size, ball fill level, and rpm on the particle breakage kinetics were systematically investigated at both mills, with an additional parameter (flow-rate) in the case of the flow-through mill. The breakage rate was found to follow power-law kinetics with respect to dimensionless time, with an asymptotic d50 particle size in the range of 200-300nm. In the case of the flow-through mill, the number of theoretical passes through the mill was found to be an important scale-up parameter.

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

    Science.gov (United States)

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

    2015-06-01

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

  3. A Community Based Systems Diagram of Obesity Causes.

    Directory of Open Access Journals (Sweden)

    Steven Allender

    Full Text Available Application of system thinking to the development, implementation and evaluation of childhood obesity prevention efforts represents the cutting edge of community-based prevention. We report on an approach to developing a system oriented community perspective on the causes of obesity.Group model building sessions were conducted in a rural Australian community to address increasing childhood obesity. Stakeholders (n = 12 built a community model that progressed from connection circles to causal loop diagrams using scripts from the system dynamics literature. Participants began this work in identifying change over time in causes and effects of childhood obesity within their community. The initial causal loop diagram was then reviewed and elaborated by 50 community leaders over a full day session.The process created a causal loop diagram representing community perceptions of determinants and causes of obesity. The causal loop diagram can be broken down into four separate domains; social influences; fast food and junk food; participation in sport; and general physical activity.This causal loop diagram can provide the basis for community led planning of a prevention response that engages with multiple levels of existing settings and systems.

  4. Intelligent Drug Delivery System Using UML Diagrams Analysis

    Institute of Scientific and Technical Information of China (English)

    CUI Qi-feng; LIU Cheng-liang; ZHA Xuan F

    2008-01-01

    A novel intelligent drug delivery system potential for the more effective therapy of the diabeticswas proposed, and the composition of system was analyzed. Based on the design of micro-electro-mechanicalsystems (MEMS), an iterative modeling process was introduced. Unified modeling language (UML) was em-ployed to describe the function requirement, and different diagrams were built up to explore the static model,the dynamic model and the employment model. The mapping analysis of different diagrams can simply verifythe consistency and completeness of the system model.

  5. Phase separating colloid polymer mixtures in shear flow

    NARCIS (Netherlands)

    Derks, D.; Aarts, D.G.A.L.; Bonn, D.; Imhof, A.

    2008-01-01

    We study the process of phase separation of colloid polymer mixtures in the (spinodal) two-phase region of the phase diagram in shear flow. We use a counter-rotating shear cell and image the system by means of confocal laser scanning microscopy. The system is quenched from an initially almost homoge

  6. Sequential Voronoi diagram calculations using simple chemical reactions

    CERN Document Server

    Costello, Ben de Lacy; Adamatzky, Andy

    2012-01-01

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

  7. UML activity diagrams in requirements specification of logic controllers

    Science.gov (United States)

    Grobelna, Iwona; Grobelny, Michał

    2015-12-01

    Logic controller specification can be prepared using various techniques. One of them is the wide understandable and user-friendly UML language and its activity diagrams. Using formal methods during the design phase increases the assurance that implemented system meets the project requirements. In the approach we use the model checking technique to formally verify a specification against user-defined behavioral requirements. The properties are usually defined as temporal logic formulas. In the paper we propose to use UML activity diagrams in requirements definition and then to formalize them as temporal logic formulas. As a result, UML activity diagrams can be used both for logic controller specification and for requirements definition, what simplifies the specification and verification process.

  8. Project Management Plan for the INEL technology logic diagrams

    Energy Technology Data Exchange (ETDEWEB)

    Rudin, M.J.

    1992-10-01

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

  9. Project Management Plan for the INEL technology logic diagrams

    Energy Technology Data Exchange (ETDEWEB)

    Rudin, M.J.

    1992-10-01

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

  10. Energy flows, material cycles and global development. A process engineering approach to the Earth system

    Energy Technology Data Exchange (ETDEWEB)

    Schaub, Georg [Karlsruher Institut fuer Technologie, Karlsruhe (Germany). Engler-Bunte-Institut; Turek, Thomas [TU Clausthal, Clausthal-Zellerfeld (Germany). Inst. fuer Chemische Verfahrenstechnik

    2011-07-01

    The book deals with the global flows of energy and materials, and changes caused by human activities. Based on these facts, the limitations of anthropogenic energy and material flows and the resulting consequences for the development of human societies are discussed. Different scenarios for lifestyle patterns are correlated with the world's future development of energy supply and climate. The book provides a process engineering approach to the Earth system and global development. It requires basic understanding of mathematics, physics, chemistry and biology, and provides an insight into the complex matter for readers ranging from undergraduate students to experts. (orig.)

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

    Science.gov (United States)

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

    2014-01-01

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

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

    Science.gov (United States)

    Gu, Quan; Hayes-Gill, Barrie R; Morgan, Stephen P

    2008-04-20

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

  13. Numerical analysis of the heat transfer and fluid flow in the butt-fusion welding process

    Science.gov (United States)

    Yoo, Jae Hyun; Choi, Sunwoong; Nam, Jaewook; Ahn, Kyung Hyun; Oh, Ju Seok

    2017-02-01

    Butt-fusion welding is an effective process for welding polymeric pipes. The process can be simplified into two stages. In heat soak stage, the pipe is heated using a hot plate contacted with one end of the pipe. In jointing stage, a pair of heated pipes is compressed against one another so that the melt regions become welded. In previous works, the jointing stage that is highly related to the welding quality was neglected. However, in this study, a finite element simulation is conducted including the jointing stage. The heat and momentum transfer are considered altogether. A new numerical scheme to describe the melt flow and pipe deformation for the butt-fusion welding process is introduced. High density polyethylene (HDPE) is used for the material. Flow via thermal expansion of the heat soak stage, and squeezing and fountain flow of the jointing stage are well reproduced. It is also observed that curling beads are formed and encounter the pipe body. The unique contribution of this study is its capability of directly observing the flow behaviors that occur during the jointing stage and relating them to welding quality.

  14. Selected Remarks about Computer Processing in Terms of Flow Control and Statistical Mechanics

    Directory of Open Access Journals (Sweden)

    Dominik Strzałka

    2016-03-01

    Full Text Available Despite the fact that much has been said about processing in computer science, it seems that there is still much to do. A classical approach assumes that the computations done by computers are a kind of mathematical operation (calculations of functions values and have no special relations to energy transformation and flow. However, there is a possibility to get a new view on selected topics, and as a special case, the sorting problem is presented; we know many different sorting algorithms, including those that have complexity equal to O(n lg(n , which means that this problem is algorithmically closed, but it is also possible to focus on the problem of sorting in terms of flow control, entropy and statistical mechanics. This is done in relation to the existing definitions of sorting, connections between sorting and ordering and some important aspects of computer processing understood as a flow that are not taken into account in many theoretical considerations in computer science. The proposed new view is an attempt to change the paradigm in the description of algorithms’ performance by computational complexity and processing, taking into account the existing references between the idea of Turing machines and their physical implementations. This proposal can be expressed as a physics of computer processing; a reference point to further analysis of algorithmic and interactive processing in computer systems.

  15. Retrospect and Prospect of the Influence Diagram

    Institute of Scientific and Technical Information of China (English)

    LiuYanqiong; ShenYongping; ChenYingwu

    2005-01-01

    The evaluation algorithm and the application of the influence diagram were surveyed, which argues that to construct an explicit,compact and objective influence diagram is of the most importance. There are two suggested ways for realization of the influence diagram: introducing the achievements of the modern psychology, cognitive science, behavior science, and so on to represent and solve uncertainty to build a well-constructed influence diagram; based on the observed data to build an influence diagram. Also, the limitations of the influence diagram were analyzed, such as that it cannot deal with asynunetric problems efficiently, cannot picture dynamic problems,cannot model the problems with a limitless horizon, and ther is no highly efficient algorithm. And some potential methods to overcome these limitations were pointed out.

  16. Continuation of point clouds via persistence diagrams

    Science.gov (United States)

    Gameiro, Marcio; Hiraoka, Yasuaki; Obayashi, Ippei

    2016-11-01

    In this paper, we present a mathematical and algorithmic framework for the continuation of point clouds by persistence diagrams. A key property used in the method is that the persistence map, which assigns a persistence diagram to a point cloud, is differentiable. This allows us to apply the Newton-Raphson continuation method in this setting. Given an original point cloud P, its persistence diagram D, and a target persistence diagram D‧, we gradually move from D to D‧, by successively computing intermediate point clouds until we finally find a point cloud P‧ having D‧ as its persistence diagram. Our method can be applied to a wide variety of situations in topological data analysis where it is necessary to solve an inverse problem, from persistence diagrams to point cloud data.

  17. Mathematical review on source-type diagrams

    Science.gov (United States)

    Aso, Naofumi; Ohta, Kazuaki; Ide, Satoshi

    2016-03-01

    A source-type diagram is a visualization tool used to display earthquake sources, including double-couples, compensated linear vector dipoles, and isotropic deformation. Together with recent observations of non-double-couple events in a variety of tectonic settings, it is important to be able to recognize the source type intuitively from a representative diagram. Since previous works have proposed diagrams created using a range of projections, we review these diagrams in the framework of the moment tensor eigenvalue space. For further applications, we also provide complete formulas for conversion between moment tensor representation and the coordinate system of each diagram style. Using both a global catalog and synthetic data, we discuss differences between types of diagrams and the relative effectiveness of each.

  18. Sequential maneuvering decisions based on multi-stage influence diagram in air combat

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A multi-stage influence diagram is used to model the pilot's sequential decision making in one on one air combat.The model based on the multi-stage influence diagram graphically describes the elements of decision process,and contains a point-mass model for the dynamics of an aircraft and takes into account the decision maker's Dreferences under uncertain conditions.Considering an active opponent,the opponent's maneuvers can be modeled stochastically.The solution of multistage influence diagram Can be obtained by converting the multistage influence diagram into a two-level optimization problem.The simulation results show the model is effective.

  19. Gravity On-shell Diagrams

    CERN Document Server

    Herrmann, Enrico

    2016-01-01

    We study on-shell diagrams for gravity theories with any number of supersymmetries and find a compact Grassmannian formula in terms of edge variables of the graphs. Unlike in gauge theory where the analogous form involves only $\\dlog$-factors, in gravity there is a non-trivial numerator as well as higher degree poles in the edge variables. Based on the structure of the Grassmannian formula for $\\N=8$ supergravity we conjecture that gravity loop amplitudes also possess similar properties. In particular, we find that there are only logarithmic singularities on cuts with finite loop momentum, poles at infinity are present and loop amplitudes show special behavior on certain collinear cuts. We demonstrate on 1-loop and 2-loop examples that the behavior on collinear cuts is a highly non-trivial property which requires cancellations between all terms contributing to the amplitude.

  20. Solving Limited Memory Influence Diagrams

    CERN Document Server

    Mauá, Denis Deratani; Zaffalon, Marco

    2011-01-01

    We present a new algorithm for exactly solving decision making problems represented as influence diagrams. We do not require the usual assumptions of no forgetting and regularity; this allows us to solve problems with simultaneous decisions and limited information. The algorithm is empirically shown to outperform a state-of-the-art algorithm on randomly generated problems of up to 150 variables and $10^{64}$ solutions. We show that the problem is NP-hard even if the underlying graph structure of the problem has small treewidth and the variables take on a bounded number of states, but that a fully polynomial time approximation scheme exists for these cases. Moreover, we show that the bound on the number of states is a necessary condition for any efficient approximation scheme.

  1. Mapping the QCD phase diagram

    CERN Document Server

    Rajagopal, K

    1999-01-01

    The QCD vacuum in which we live, which has the familiar hadrons as its excitations, is but one phase of QCD, and far from the simplest one at that. One way to better understand this phase and the nonperturbative dynamics of QCD more generally is to study other phases and the transitions between phases. We are engaged in a voyage of exploration, mapping the QCD phase diagram as a function of temperature T and baryon number chemical potential mu . Because of asymptotic freedom, the high temperature and high baryon density phases of QCD are more simply and more appropriately described in terms of quarks and gluons as degrees of freedom, rather than hadrons. The chiral symmetry breaking condensate which characterizes the vacuum phase melts away. At high densities, quarks form Cooper pairs and new condensates develop. The formation of such superconducting phases requires only weak attractive interactions; these phases may nevertheless break chiral symmetry and have excitations which are indistinguishable from thos...

  2. Phase diagram of ammonium nitrate

    Science.gov (United States)

    Dunuwille, M.; Yoo, C. S.

    2014-05-01

    Ammonium Nitrate (AN) has often subjected to uses in improvised explosive devices, due to its wide availability as a fertilizer and its capability of becoming explosive with slight additions of organic and inorganic compounds. Yet, the origin of enhanced energetic properties of impure AN (or AN mixtures) is neither chemically unique nor well understood -resulting in rather catastrophic disasters in the past1 and thereby a significant burden on safety in using ammonium nitrates even today. To remedy this situation, we have carried out an extensive study to investigate the phase stability of AN at high pressure and temperature, using diamond anvil cells and micro-Raman spectroscopy. The present results confirm the recently proposed phase IV-to-IV' transition above 17 GPa2 and provide new constraints for the melting and phase diagram of AN to 40 GPa and 400 °C.

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

    Energy Technology Data Exchange (ETDEWEB)

    Yannis C. Yortsos

    2003-02-01

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

  4. Hofstadter Butterfly Diagram in Noncommutative Space

    CERN Document Server

    Takahashi, H; Takahashi, Hidenori; Yamanaka, Masanori

    2006-01-01

    We study an energy spectrum of electron moving under the constant magnetic field in two dimensional noncommutative space. It take place with the gauge invariant way. The Hofstadter butterfly diagram of the noncommutative space is calculated in terms of the lattice model which is derived by the Bopp's shift for space and by the Peierls substitution for external magnetic field. We also find the fractal structure in new diagram. Although the global features of the new diagram are similar to the diagram of the commutative space, the detail structure is different from it.

  5. The spectroscopic Hertzsprung-Russell diagram

    CERN Document Server

    Langer, N

    2014-01-01

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

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

    Science.gov (United States)

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

    2014-05-01

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

  7. Acetylene Flow Rate as a Crucial Parameter of Vacuum Carburizing Process of Modern Tool Steels

    Directory of Open Access Journals (Sweden)

    Rokicki P.

    2016-12-01

    Full Text Available Carburizing is one of the most popular and wide used thermo-chemical treatment methods of surface modification of tool steels. It is a process based on carbon diffusive enrichment of the surface material and is applied for elements that are supposed to present higher hardness and wear resistance sustaining core ductility. Typical elements submitted to carburizing process are gears, shafts, pins and bearing elements. In the last years, more and more popular, especially in highly advanced treatment procedures used in the aerospace industry is vacuum carburizing. It is a process based on chemical treatment of the surface in lower pressure, providing much higher uniformity of carburized layer, lower process cost and much lesser negative impact on environment to compare with conventional carburizing methods, as for example gas carburizing in Endo atmosphere. Unfortunately, aerospace industry requires much more detailed description of the phenomena linked to this process method and the literature background shows lack of tests that could confirm fulfilment of all needed requirements and to understand the process itself in much deeper meaning. In the presented paper, authors focused their research on acetylene flow impact on carburized layer characteristic. This is one of the most crucial parameters concerning homogeneity and uniformity of carburized layer properties. That is why, specific process methodology have been planned based on different acetylene flow values, and the surface layer of the steel gears have been investigated in meaning to impact on any possible change in potential properties of the final product.

  8. Cavity formation and surface modeling of laser milling process under a thin-flowing water layer

    Science.gov (United States)

    Tangwarodomnukun, Viboon

    2016-11-01

    Laser milling process normally involves a number of laser scans over a workpiece to selectively remove the material and then to form cavities with shape and dimensions required. However, this process adversely causes a heat accumulation in work material, which can in turn damage the laser-milled area and vicinity in terms of recast deposition and change of material properties. Laser milling process performing in a thin-flowing water layer is a promising method that can overcome such damage. With the use of this technique, water can flush away the cut debris and at the same time cool the workpiece during the ablation. To understand the potential of this technique for milling application, the effects of process parameters on cavity dimensions and surface roughness were experimentally examined in this study. Titanium sheet was used as a workpiece to be milled by a nanosecond pulse laser under different water flow velocities. A smooth and uniform cut feature can be obtained when the metal was ablated under the high laser pulse frequency and high water flow velocity. Furthermore, a surface model based on the energy balance was developed in this study to predict the cavity profile and surface roughness. By comparing to the experiments, the predicted profiles had a good agreement with the measured ones.

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

    Directory of Open Access Journals (Sweden)

    Yan Yang

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

  10. Heat flow and thermal processes in the Jornada delMuerto, New Mexico

    Science.gov (United States)

    Reiter, M.

    1985-01-01

    Most heat flow data in rifts are uncertain largely because of hydrologic disturbances in regions of extensive fracturing. Estimates of heat flow in deep petroleum tests within a large basin of the Rio Grande rift, which has suffered little syn-rift fracturing, may begin to provide clearer insight into the relationships between high heat flow and crustal thinning processes. The Jornada del Muerto is a large basin located in the Rio Grande rift of south central New Mexico. The region of interest within the Jornada del Muerto is centered about 30 km east of the town of Truth or Consequences, and is approximately 60 km north-south by 30 km east-west. High heat flows are estimated for the region. Values increase from about 90 mWm(-2) in the northern part of the study area to about 125 mWm(-2) in the southern part. These high heat flows are rather enigmatic because in the immediate vicinities of the sites there is little evidence of Cenozoic volcanism or syn-rift extensional tectonics. It is suggested that the geothermal anomaly in the southern Jornada del Muerto (approx. 125 to approx. 95 mWm(-2) results from some type of mass movement-heat transfer mechanism operating in the crust just below the elastic layer. This conclusion is consistent with the geologic and geophysical data which describe a thin crust, apparently devoid of features indicative of extensional-tectonics in the upper part of the lastic crust.

  11. Debris flows on the Great Kobuk Sand Dunes, Alaska: Implications for analogous processes on Mars

    Science.gov (United States)

    Hooper, Donald M.; Dinwiddie, Cynthia L.

    2014-02-01

    We observed niveo-aeolian deposits, denivation features, and small meltwater-induced debris flows that had formed at the Great Kobuk Sand Dunes, northwestern interior Alaska in late March 2010. This high-latitude, cold-climate dune field is being studied as a planetary analog to improve our understanding of factors that may trigger debris flows on the lee slopes of martian aeolian dunes. Debris flows consisted of a sand and liquid water mixture that cascaded down the lee slopes of two barchanoid dunes on days when measured ground surface temperatures were below freezing. We hypothesize that relatively dark sand on snow caused local hot spots where solar radiation could be absorbed by the sand and conducted into the underlying snow, enabling meltwater to form and sand to be mobilized. This investigation provides insights into the interactions between niveo-aeolian deposition, slope aspect and insolation, thawing, and initiation of alluvial processes. These debris flows are morphologically similar to those associated with seasonal gullies or erosion tracks visible on the slopes of mid- to high-latitude dune fields in both martian hemispheres. Localized heating and thawing at scales too small for orbital sensors to identify may yield martian debris flows at current climate conditions.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-12-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-12-01

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

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

    Science.gov (United States)

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

    2014-07-01

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

  15. On the Different Ways That Mathematicians Use Diagrams in Proof Construction

    Science.gov (United States)

    Samkoff, Aron; Lai, Yvonne; Weber, Keith

    2012-01-01

    The processes by which individuals can construct proofs based on visual arguments are poorly understood. We investigated this issue by presenting eight mathematicians with a task that invited the construction of a diagram, and examined how they used this diagram to produce a formal proof. The main findings were that participants varied in the…

  16. A Business Process Model and Reengineering Plan for the Student Services Department of the Marine Corps Institute.

    Science.gov (United States)

    1997-09-01

    Department (SSD). The objective of this thesis is to develop the As-Is process model , redesign the processes to increase efficiency and reduce costs, and...develop a To-Be process model to improve the current business processes. Additionally, data flow diagrams of the To-Be processes are developed to assist

  17. UML活动图的形式语义%The Formal Semantics of an UML Activity Diagram

    Institute of Scientific and Technical Information of China (English)

    梁义芝; 王延章; 刘云飞

    2004-01-01

    Due to lack of strictly defined formal semantics, an UML activity diagram is unsuitable for the tasks of formal analysis, verification and assertion on the system it describes. In this paper, Petri net is used to define the formal semantics of an UML activity diagram containing object flow states, laying a foundation for the precise description and analysis of a workflow system.

  18. Mathematical Model for Fluid Flow and Heat Transfer Processes in Plate Exchanger

    Directory of Open Access Journals (Sweden)

    Cvete B. Dimitrieska

    2015-11-01

    Full Text Available Within the analytical solution of the system of equations which solve fluid flow and heat transfer processes, the elliptical and parabolic differential equations based on initial and boundary conditions is usually unfamiliar in a closed form. Numerical solution of equation system is necessarily obtained by discretization of equations. When system of equations relate to estimation of two dimensional stationary problems, the applicable method for estimation in basic two – dimensional form is recommended.

  19. Processing Methods and Storage Conditions on Chocolate and Coffee Powder Flow Properties

    OpenAIRE

    Gong, Sunland L; Della Bella, Andrea; Carvajal, Teresa M.

    2015-01-01

    Powders are widely used in a countless number of industries, and are crucial to the quality control of products in areas such as pharmaceuticals and food. Particle physicochemical properties (morphology, solid state – crystalline, amorphous or both) are important factors for powder flow, which in turn can have significant impact on the stability, performance, and presentation of powders. Different processing methods as well as storage conditions such as relative humidity (RH) can drastically ...

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

    Directory of Open Access Journals (Sweden)

    E. Dendy Sloan

    2010-12-01

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

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

    Science.gov (United States)

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

    2015-02-17

    reactive gas in a given reaction mixture. We have developed a tube-in-tube reactor device consisting of a pair of concentric capillaries in which pressurized gas permeates through an inner Teflon AF-2400 tube and reacts with dissolved substrate within a liquid phase that flows within a second gas impermeable tube. This Account examines our efforts toward the development of a simple, unified methodology for the processing of gaseous reagents in flow by way of development of a tube-in-tube reactor device and applications to key C-C, C-N, and C-O bond forming and hydrogenation reactions. We further describe the application to multistep reactions using solid-supported reagents and extend the technology to processes utilizing multiple gas reagents. A key feature of our work is the development of computer-aided imaging techniques to allow automated in-line monitoring of gas concentration and stoichiometry in real time. We anticipate that this Account will illustrate the convenience and benefits of membrane tube-in-tube reactor technology to improve and concomitantly broaden the scope of gas/liquid/solid reactions in organic synthesis.

  2. Investigating preferential flow processes in soils using anisotropy in electrical resistivity

    Science.gov (United States)

    Al-Hazaimay, S.; Huisman, J. A.; Zimmermann, E.; Kemna, A.; Vereecken, H.

    2012-12-01

    Macropores occupy a small volume fraction of the pore space in the vadose zone. Water and solutes can quickly bypass the vadose zone through these macropores in a process known as macropore preferential flow. In the last few decades, many efforts were made to improve understanding the macropore preferential flow processes because of their importance in transporting agrochemicals and contaminants to the groundwater. Unfortunately, very few measurement methods provide insights into these preferential flow processes. In this context, the objective of this study is to evaluate whether anisotropy in electrical resistivity can be used to identify the existence of flow in macropores and perhaps even to characterize the exchange between macropores and bulk soil. In a first step, infiltration into a soil column with an artificial macropore was simulated using the HYDRUS software package that solves the pseudo three-dimensional axisymmetric Richards equation. The simulated temporal development of the resistivity anisotropy was obtained by solving the Poisson equation in MATLAB after converting the simulated water content distributions to electrical resistivity distributions. At the beginning of the simulation, a small anisotropy ratio was simulated because of the presence of the empty ('deactivated') macropore in the moist matrix. As soon as the infiltration process started, macropore flow occurred and both the horizontal and vertical resistivity decreased strongly. However, the vertical and horizontal resistivity reacted differently because of the presence of the conductive ('activated') macropore, which led to anisotropy in the resistivity. As soon as infiltration into the macropore stopped, water re-distributed from the macropore to the matrix domain and contrasts in electrical resistivity decreased within the column. To verify the simulation results in the laboratory, we measured the temporal dynamics of the anisotropy in resistivity during water infiltration into a soil

  3. Ferroelectric phase diagram of PVDF:PMMA

    NARCIS (Netherlands)

    Li, M.; Stingelin, N.; Michels, J.J.; Spijkman, M.-J.; Asadi, K.; Feldman, K.; Blom, P.W.M.; Leeuw, D.M. de

    2012-01-01

    We have investigated the ferroelectric phase diagram of poly(vinylidene fluoride) (PVDF) and poly(methyl methacrylate) (PMMA). The binary nonequilibrium temperature composition diagram was determined and melting of α- and β-phase PVDF was identified. Ferroelectric β-PVDF:PMMA blend films were made b

  4. Ferroelectric Phase Diagram of PVDF : PMMA

    NARCIS (Netherlands)

    Li, Mengyuan; Stingelin, Natalie; Michels, Jasper J.; Spijkman, Mark-Jan; Asadi, Kamal; Feldman, Kirill; Blom, Paul W. M.; de Leeuw, Dago M.

    2012-01-01

    We have investigated the ferroelectric phase diagram of poly(vinylidene fluoride) (PVDF) and poly(methyl methacrylate) (PMMA). The binary nonequilibrium temperature composition diagram was determined and melting of alpha- and beta-phase PVDF was identified. Ferroelectric beta-PVDF:PMMA blend films w

  5. Automatically extracting class diagrams from spreadsheets

    NARCIS (Netherlands)

    Hermans, F.; Pinzger, M.; Van Deursen, A.

    2010-01-01

    The use of spreadsheets to capture information is widespread in industry. Spreadsheets can thus be a wealthy source of domain information. We propose to automatically extract this information and transform it into class diagrams. The resulting class diagram can be used by software engineers to under

  6. Lubrication modes and the IRG transition diagram

    NARCIS (Netherlands)

    Schipper, D.J.; Gee, de A.W.J.

    1995-01-01

    The relationship between a Lubrication Mode Diagram (LMD) for concentrated contacts (LCC's) and the IRG transition diagram has been studied. In addition, scuffing results, obtained by the IRG (International Research Group) have been analysed, as well as the results of scuffing tests performed by dif

  7. Structural Controllability and Observability in Influence Diagrams

    OpenAIRE

    Chan, Brian Y.; Shachter, Ross D.

    2013-01-01

    Influence diagram is a graphical representation of belief networks with uncertainty. This article studies the structural properties of a probabilistic model in an influence diagram. In particular, structural controllability theorems and structural observability theorems are developed and algorithms are formulated. Controllability and observability are fundamental concepts in dynamic systems (Luenberger 1979). Controllability corresponds to the ability to control a system while observability a...

  8. Resummation of Cactus Diagrams in Lattice QCD

    CERN Document Server

    Panagopoulos, H

    1998-01-01

    We show how to perform a resummation, to all orders in perturbation theory, of a certain class of gauge invariant diagrams in Lattice QCD. These diagrams are often largely responsible for lattice artifacts. Our resummation leads to an improved perturbative expansion. Applied to a number of cases of interest, this expansion yields results remarkably close to corresponding nonperturbative estimates.

  9. Simulating the DISAMATIC process using the discrete element method — a dynamical study of granular flow

    DEFF Research Database (Denmark)

    Hovad, Emil; Spangenberg, Jon; Larsen, P.

    2016-01-01

    The discrete element method (DEM) is applied to simulate the dynamics of the flow of green sand while filling a mould using the DISAMATIC process. The focus is to identify relevant physical experiments that can be used to characterize the material properties of green sand in the numerical model....... The DEM parameters describing the static friction coefficients are obtained using a ring shear tester and the rolling resistance and cohesion value is subsequently calibrated with a sand pile experiment. The calibrated DEM model is used to model the sand shot in the DISAMATIC process for three different...

  10. Comparative Study on DFD to UML Diagrams Transformations

    CERN Document Server

    Jilani, Atif A A; Nadeem, Aamer

    2011-01-01

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

  11. Phase diagram of elastic spheres.

    Science.gov (United States)

    Athanasopoulou, L; Ziherl, P

    2017-02-15

    Experiments show that polymeric nanoparticles often self-assemble into several non-close-packed lattices in addition to the face-centered cubic lattice. Here, we explore theoretically the possibility that the observed phase sequences may be associated with the softness of the particles, which are modeled as elastic spheres interacting upon contact. The spheres are described by two finite-deformation theories of elasticity, the modified Saint-Venant-Kirchhoff model and the neo-Hookean model. We determine the range of indentations where the repulsion between the spheres is pairwise additive and agrees with the Hertz theory. By computing the elastic energies of nine trial crystal lattices at densities far beyond the Hertzian range, we construct the phase diagram and find the face- and body-centered cubic lattices as well as the A15 lattice and the simple hexagonal lattice, with the last two being stable at large densities where the spheres are completely faceted. These results are qualitatively consistent with observations, suggesting that deformability may indeed be viewed as a generic property that determines the phase behavior in nanocolloidal suspensions.

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

    Science.gov (United States)

    Schenker, M C; Pourquié, M J B M; Eskin, D G; Boersma, B J

    2013-01-01

    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.

  13. Persistence Diagrams and the Heat Equation Homotopy

    CERN Document Server

    Fasy, Brittany Terese

    2010-01-01

    Persistence homology is a tool used to measure topological features that are present in data sets and functions. Persistence pairs births and deaths of these features as we iterate through the sublevel sets of the data or function of interest. I am concerned with using persistence to characterize the difference between two functions f, g : M -> R, where M is a topological space. Furthermore, I formulate a homotopy from g to f by applying the heat equation to the difference function g-f. By stacking the persistence diagrams associated with this homotopy, we create a vineyard of curves that connect the points in the diagram for f with the points in the diagram for g. I look at the diagrams where M is a square, a sphere, a torus, and a Klein bottle. Looking at these four topologies, we notice trends (and differences) as the persistence diagrams change with respect to time.

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

    Science.gov (United States)

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

    2001-05-01

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

  15. Process Based Prediction of Flow Distribution at Ungauged Himalayan Catchments using Satellite Data

    Science.gov (United States)

    Muller, M. F.; Thompson, S. E.

    2013-12-01

    In-line hydropower (IHP), whereby micro hydropower turbines are integrated in gravity fed rural water supply systems, is a promising yet underutilized infrastructure synergy in rural mountainous areas of developing countries. In Nepal, although institutional and economic considerations are critical, the available local hydropower potential - in particular the flow availability to drive turbines - is the key feasibility criterion. Yet flow projections in remote areas remain a significant challenge largely due to difficult access and data scarcity. We recently showed that satellite data could be successfully adjusted to generate parameters describing the frequency and intensity of daily rainfall. The flow predictions needed for hydropower siting relate primarily to a frequency domain description, specifically the fluw duration curves, which are closely controlled by these rainfall parameters. This project combines bias-corrected satellite rainfall parameters with remotely sensed stationary watershed data to predict the flow duration curves at ungauged Himalayan watersheds. In particular, we compare the performance of several approaches with different levels of process representation, applied to sparsely gauged, snow-fed and topographically complex catchments with highly seasonal rainfall.

  16. Embedding theorem for spike trains and active processes in chaotic flows

    Science.gov (United States)

    Nishikawa, Takashi

    2000-10-01

    This thesis contains two separate topics. The first topic concerns proof of a theorem that justifies the method of reconstruction of dynamics using inter-event time intervals. In particular, we prove that the function from an invariant set of a typical dynamical system into R d, defined by successive inter-event time intervals from integrate-and-fire dynamics, is prevalently a topological embedding. This allows topological information about a dynamical attractor to be inferred from spike trains. The second topic is the active processes of particles advected by chaotic flows. While previous studies focused on the active processes of massless point particles, or an ideal tracer, we discuss the particles with finite mass and size. Their equations of motion are inherently dissipative, due to the Stokes drag. The dynamics of the advected particles can be chaotic even with a flow field that is simply time-periodic. Similarly to the case of ideal tracers, whose dynamics is Hamiltonian, chemical or biological activity involving such particles advected by fluid flows can be analyzed using the theory of chaotic dynamics. We choose the cellular vortex flow field with periodically varying vorticity as an example, and analyze the dynamics of the reaction of autocatalytic type, A + B → 2 B, and of coalescence type, B + B → B. Another assumption that the previous studies on the active processes had, was that the reaction of all particles in the system occurs simultaneously. Here we investigate the effect of asynchronism of the autocatalytic reaction taking place in an open hydrodynamical flow, by assigning each particle in the system with a phase to differentiate the timing of their reactions, but not their periodicity. The chaotic saddle in the flow dynamics acts as a catalyst and enhances the reaction in the same fashion as in the case of synchronous reaction that was studied previously. However, we show that, in certain range of a parameter, the group of particles with a

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

    Science.gov (United States)

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

    1994-12-01

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

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

    Science.gov (United States)

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

    2012-05-15

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

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

    Science.gov (United States)

    Chinapirom, Teerapat; Witkowski, Ulf; Rueckert, Ulrich

    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.

  20. Numerical simulation of gas flow process in mining-induced crack network

    Institute of Scientific and Technical Information of China (English)

    Zhou; Hongwei; Liu; Jinfeng; Xue; Dongjie; Yi; Haiyang; Xue; Junhua

    2012-01-01

    The exploitation of coal bed methane or coal gas is one of the most effective solutions of the problem of coal gas hazard.A better understanding of gas flow in mining-induced cracks plays an important role in comprehensive development and utilization of coal gas as well as prevention of coal gas hazard.This paper presents a case study of gas flow in mining-induced crack network regarding the situation of low permeability of coal seam.A two-dimensional physical model is constructed on the basis of geological background of mining face No.1122(1) in coal seam No.11-2,Zhangji Coal Mine,Huainan Mining Group Corporation.The mining-induced stress and cracks in overburden rocks are obtained by simulating an extraction in physical model.An evolution of mining-induced cracks in the process of advancing of coal mining face is characterized and three typical crack networks are taken from digital photos by means of image analysis.Moreover,the numerical software named COMSOL Multiphysics is employed to simulate the process of gas flow in three representative crack networks.Isograms of gas pressure at various times in mining-induced crack networks are plotted,suggesting a shape and dimension of gas accumulation area.

  1. The distribution of length scales generated by mixing processes in time-p eriodic chaotic flows

    Science.gov (United States)

    Muzzio, Fernando; Alvarez, Mario; Cerbelli, Stefano

    1997-11-01

    This talk explores in some detail the evolution of the spatial structure and th e statistical properties of partially mixed systems as they evolve on a torus by using a direct numerical simulation of the evolution of continuous material lin es as they are stretched, reoriented, and folded by the flow. In the time scale s of interest to mixing processes, such material lines grow exponentially fast, but much faster than predicted by the Lyapunov exponent. The filament develops into a self-similar structure; frequency distribution of filament densities corr esponding to different times collapses onto an invariant curve by a simple homog eneous scaling. It is shown that this behavior is a direct consequence of a gen eric asymptotic directionality property characteristic of 2D time-periodic flows . Mixture microstructure is also analyzed by computing the evolution of th e distribution of length scales in the flow. Once again, the result is a family of self-similar curves that scale homogeneously by the mean length scale, which collapses in inverse proportion to the rate of growth of the filament. It is s hown that this rate of collapse, which has direct relevance to mixing applicatio ns, can be accurately and straightforwardly predicted from the ergodic average o f the stretching field. Implications for mixing processes in realistic systems are also discussed.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-10-01

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

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

    Science.gov (United States)

    Huang, Qizhong; Ren, Mingfa; Chen, Haoran

    2013-06-01

    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.

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

    Science.gov (United States)

    Umbrello, Domenico; Rizzuti, Stefania; Outeiro, José C.; Shivpuri, Rajiv

    2007-04-01

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

  5. Faceting diagram for sticky steps

    Directory of Open Access Journals (Sweden)

    Noriko Akutsu

    2016-03-01

    Full Text Available Faceting diagrams for the step-faceting zone, the step droplet zone, and the Gruber-Mullins-Pokrovsky-Talapov (GMPT zone for a crystal surface are obtained by using the density matrix renormalization group method to calculate the surface tension. The model based on these calculations is the restricted solid-on-solid (RSOS model with a point-contact-type step-step attraction (p-RSOS model on a square lattice. The point-contact-type step-step attraction represents the energy gain obtained by forming a bonding state with orbital overlap at the meeting point of the neighboring steps. In the step-faceting zone, disconnectedness in the surface tension leads to the formation of a faceted macrostep on a vicinal surface at equilibrium. The disconnectedness in the surface tension also causes the first-order shape transition for the equilibrium shape of a crystal droplet. The lower zone boundary line (ZBL, which separates the step-faceting zone and the step droplet zone, is obtained by the condition γ 1 = lim n → ∞ γ n / n , where γn is the step tension of the n-th merged step. The upper ZBL, which separates the GMPT zone and the step droplet zone, is obtained by the condition Aq,eff = 0 and Bq,eff = 0, where Aq,eff and Bq,eff represent the coefficients for the | q → | 2 term and the | q → | 3 term, respectively, in the | q → | -expanded form of the surface free energy f eff ( q → . Here, q → is the surface gradient relative to the (111 surface. The reason why the vicinal surface inclined in the 〈101〉 direction does not exhibit step-faceting is explained in terms of the one-dimensional spinless quasi-impenetrable attractive bosons at absolute zero.

  6. Numerical Analysis on Flow and Solute Transmission during Heap Leaching Processes

    Directory of Open Access Journals (Sweden)

    J. Z. Liu

    2015-01-01

    Full Text Available Based on fluid flow and rock skeleton elastic deformation during heap leaching process, a deformation-flow coupling model is developed. Regarding a leaching column with 1 m height, solution concentration 1 unit, and the leaching time being 10 days, numerical simulations and indoors experiment are conducted, respectively. Numerical results indicate that volumetric strain and concentration of solvent decrease with bed’s depth increasing; while the concentration of dissolved mineral increases firstly and decreases from a certain position, the peak values of concentration curves move leftward with time. The comparison between experimental results and numerical solutions is given, which shows these two are in agreement on the whole trend.

  7. Process Design of Continuous-Flow Pervaporation Separa tion for Alcohol Dehydration

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The separation characteristics of the PVA-CS (polyvinyl alcohol-chitosan) blended composite membrane for dehydration of ethanol-water mixture are examined. The relationships of flux and separation factor with the feed concentration and operation temperature are established. Using this correlated equation, the continuous-flow pervaporation process about 500 kilolitres/year dehydrated ethanol is designed. The numbers of stage and reheater are calculated by stage-by-stage method for two kinds of cascades: one with equal membrane area and the other with 10℃C of temperature decrement per section. The results show that when the numbers of stage and reheater are the same, the cascade with 10℃C of temperature decrement has more advantages than that with equal membrane area. The influences of feed concentration and flow rate on the numbers of stage and reheater in the cascades are discnssed.

  8. Self-sustaining processes at all scales in wall-bounded turbulent shear flows

    Science.gov (United States)

    Cossu, Carlo; Hwang, Yongyun

    2017-03-01

    We collect and discuss the results of our recent studies which show evidence of the existence of a whole family of self-sustaining motions in wall-bounded turbulent shear flows with scales ranging from those of buffer-layer streaks to those of large-scale and very-large-scale motions in the outer layer. The statistical and dynamical features of this family of self-sustaining motions, which are associated with streaks and quasi-streamwise vortices, are consistent with those of Townsend's attached eddies. Motions at each relevant scale are able to sustain themselves in the absence of forcing from larger- or smaller-scale motions by extracting energy from the mean flow via a coherent lift-up effect. The coherent self-sustaining process is embedded in a set of invariant solutions of the filtered Navier-Stokes equations which take into full account the Reynolds stresses associated with the residual smaller-scale motions.

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

    Directory of Open Access Journals (Sweden)

    M. K. Akhtar

    2009-04-01

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

  10. A 3-D nonisothermal flow simulation and pulling force model for injection pultrusion processes

    Science.gov (United States)

    Mustafa, Ibrahim

    1998-12-01

    Injected Pultrusion (IP) is an efficient way of producing high quality, low cost, high volume and constant cross-section polymeric composites. This process has been developed recently, and the efforts to optimize it are still underway. This work is related to the development of a 3-D non-isothermal flow model for the IP processes. The governing equations for transport of mass, momentum and, energy are formulated by using a local volume averaging approach, and the Finite Element/Control Volume method is used to solve the system of equations numerically. The chemical species balance equation is solved in the Lagrangian frame of reference whereas the energy equation is solved using Galerkin, SU (Streamline Upwind), and SUPG (Streamline Upwind Petrov Galerkin) approaches. By varying degrees of freedom and the flow rates of the resin, it is shown that at high Peclet numbers the SUPG formulation performs better than the SU and the Galerkin methods in all cases. The 3-D model predictions for degree of cure and temperature are compared with a one dimensional analytical solution and the results are found satisfactory. Moreover, by varying the Brinkman Number, it is shown that the effect of viscous dissipation is insignificant. The 3-D flow simulations have been carried out for both thin and thick parts and the results are compared with the 2-D model. It is shown that for thick parts 2-D simulations render erroneous results. The effect of changing permeability on the flow fronts is also addressed. The effect of increasing taper angle on the model prediction is also investigated. A parametric study is conducted to isolate optimum conditions for both isothermal and non-isothermal cases using a straight rectangular die and a die with a tapered inlet. Finally, a simple pulling force model is developed and the pulling force required to pull the carbon-epoxy fiber resin system is estimated for dies of varying tapered inlet.

  11. Solute transport processes in flow-event-driven stream-aquifer interaction

    Science.gov (United States)

    Xie, Yueqing; Cook, Peter G.; Simmons, Craig T.

    2016-07-01

    The interaction between streams and groundwater controls key features of the stream hydrograph and chemograph. Since surface runoff is usually less saline than groundwater, flow events are usually accompanied by declines in stream salinity. In this paper, we use numerical modelling to show that, at any particular monitoring location: (i) the increase in stream stage associated with a flow event will precede the decrease in solute concentration (arrival time lag for solutes); and (ii) the decrease in stream stage following the flow peak will usually precede the subsequent return (increase) in solute concentration (return time lag). Both arrival time lag and return time lag increase with increasing wave duration. However, arrival time lag decreases with increasing wave amplitude, whereas return time lag increases. Furthermore, while arrival time lag is most sensitive to parameters that control river velocity (channel roughness and stream slope), return time lag is most sensitive to groundwater parameters (aquifer hydraulic conductivity, recharge rate, and dispersitivity). Additionally, the absolute magnitude of the decrease in river concentration is sensitive to both river and groundwater parameters. Our simulations also show that in-stream mixing is dominated by wave propagation and bank storage processes, and in-stream dispersion has a relatively minor effect on solute concentrations. This has important implications for spreading of contaminants released to streams. Our work also demonstrates that a high contribution of pre-event water (or groundwater) within the flow hydrograph can be caused by the combination of in-stream and bank storage exchange processes, and does not require transport of pre-event water through the catchment.

  12. Phase diagram of a model of the protein amelogenin

    Science.gov (United States)

    Haaga, Jason; Pemberton, Elizabeth; Gunton, J. D.; Rickman, J. M.

    2016-08-01

    There has been considerable recent interest in the self-assembly and phase behavior of models of colloidal and protein particles with anisotropic interactions. One example of particular interest is amelogenin, an important protein involved in the formation of dental enamel. Amelogenin is primarily hydrophobic with a 25-residue charged C-terminus tail. This protein undergoes a hierarchical assembly process that is crucial to mineral deposition, and experimental work has demonstrated that the deletion of the C-terminus tail prevents this self-assembly. A simplified model of amelogenin has been proposed in which the protein is treated as a hydrophobic sphere, interacting via the Asakura-Oosawa (AO) potential, with a tethered point charge on its surface. In this paper, we examine the effect of the Coulomb interaction between the point charges in altering the phase diagram of the AO model. For the parameter case specific to amelogenin, we find that the previous in vitro experimental and model conditions correspond to the system being near the low-density edge of the metastable region of the phase diagram. Our study illustrates more generally the importance of understanding the phase diagram for proteins, in that the kinetic pathway for self-assembly and the resulting aggregate morphology depends on the location of the initial state in the phase diagram.

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

    Science.gov (United States)

    De Biase, Cecilia; Carminati, Andrea; Oswald, Sascha E; Thullner, Martin

    2013-11-01

    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

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

    DEFF Research Database (Denmark)

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

    2011-01-01

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

  15. Particle Paths of Lagrangian Velocity Distribution Simulating Yin-Yang Balance in Ancient Tai-Chi Diagram

    Institute of Scientific and Technical Information of China (English)

    Sui Lin; Tzu-Fang Chen

    2007-01-01

    The particle paths of the Lagrangian flow field simulate very well the interface curve of the Yin-Yang balance in the ancient Tai-Chi diagram. There are four forms called the "four states" in the Tai-Chi diagram. Of the four states, under Yang are the Major Yang and the Minor Yin, and under Yin are the Major Yin and the Minor Yang. The present study provides the proper positions of the four states in the ancient Tai-Chi diagram. The Fu Xi's Eight Trigrams Chart located along the ancient Tai-Chi diagram is also developed in the present study. The interface curve of Yin-Yang in the ancient Tai-Chi diagram has never been described mathematically. It can now be formulated by the equations describing the particle paths in the Lagrangian flow field.

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

    Science.gov (United States)

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

    2007-12-01

    An important part of a risk-informed, performance-based regulatory review of a potential license application for disposal of high-level radioactive waste at Yucca Mountain, Nevada, is the consideration of alternative interpretations and models of risk significant physical processes. The Nuclear Regulatory Commission (NRC) expects that simplified models will be abstracted from complex process-level models to conduct total-system performance assessments. There are several phases or steps to developing an abstracted model and its supporting basis from more detailed and complicated models for each area of the total system. For complex ambient and thermally perturbed flow in fractured tuffs of the unsaturated zone at Yucca Mountain, these steps c,an be summarized as (i) site characterization and observation, (ii) field and laboratory tests, (iii) conceptual model development, (iv) process-level numerical modeling, and (v) abstraction development. Each step is affected by uncertainty in (i) assessing parameters for models and (ii) conceptualization and understanding of governing processes. Because of the complexity and uncertainty, alternative interpretations and models become important aspects in the regulatory environment. NRC staff gain confidence in performance assessment model results through understanding the uncertainty in the various models. An example of a complex process in the unsaturated zone is seepage into drifts, which leads to liquid water potentially contacting waste packages. Seepage is a risk-important process for the unsaturated zone at Yucca Mountain because of its potential effect on waste package integrity and trainsport of potentially released radionuclides. Complexities for seepage include (i) characterization of fractures that carry flow, (ii) effect of small to intermediate scale structural features on flow, (iii) consideration of the diverse flow regimes (rivulets, film flow, capillarity) in fractures, (iv) effect of vapor transport associated

  17. STRUKTURISASI ENTITY RELATIONSHIP DIAGRAM DAN DATA FLOW DIAGRAM BERBASIS BUSINESS EVENT-DRIVEN

    Directory of Open Access Journals (Sweden)

    Suroto Adi

    2014-06-01

    Full Text Available Makalah ini berisi langkah-langkah sistematis pendekatan perancangan ERD dan DFD dengan pendekatan business event-driven yang diwakili dengan model REA, yaitu strukturisasi REA-ERD dan strukturisasi REA-DFD. Tujuan penulisan ini adalah menjelaskan langkah-langkah perancangan sistem informasi berdasarkan proses bisnis dan kegiatan bisnis, sehingga sistem informasi yang dihasilkan relevan dan mendukung visi, misi, dan strategi bisnis. Hasil yang didapat juga memperkuat pendapat sebagian analis sistem informasi tentang perlunya pendekatan dalam penyusunan model dan sebaiknya perancangan logik ERD dilakukan terlebih dahulu sebelum perancangan DFD, sehingga menyempurnakan balancing antara entitas dalam ERD dan penetapan datastore dalam DFD. Kemudahan penerapan langkah-langkah ini perlu diuji secara kualitatif maupun kuantitatif.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-07-01

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

  19. Semantic Complex Event Processing over End-to-End Data Flows

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Qunzhi [University of Southern California; Simmhan, Yogesh; Prasanna, Viktor K.

    2012-04-01

    Emerging Complex Event Processing (CEP) applications in cyber physical systems like SmartPower Grids present novel challenges for end-to-end analysis over events, flowing from heterogeneous information sources to persistent knowledge repositories. CEP for these applications must support two distinctive features - easy specification patterns over diverse information streams, and integrated pattern detection over realtime and historical events. Existing work on CEP has been limited to relational query patterns, and engines that match events arriving after the query has been registered. We propose SCEPter, a semantic complex event processing framework which uniformly processes queries over continuous and archived events. SCEPteris built around an existing CEP engine with innovative support for semantic event pattern specification and allows their seamless detection over past, present and future events. Specifically, we describe a unified semantic query model that can operate over data flowing through event streams to event repositories. Compile-time and runtime semantic patterns are distinguished and addressed separately for efficiency. Query rewriting is examined and analyzed in the context of temporal boundaries that exist between event streams and their repository to avoid duplicate or missing results. The design and prototype implementation of SCEPterare analyzed using latency and throughput metrics for scenarios from the Smart Grid domain.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-12-15

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

  1. Effect of georesource–consumer process flows on coal loss in energy supply of the Polar regions in Yakutia

    Science.gov (United States)

    Tkach, SM; Gavrilov, VL

    2017-02-01

    It is shown that the process flows of mining, haulage and utilization of coal in the Polar regions in Yakutia feature high quantitative and qualitative loss. In case the process flows are considered as integrated systems aimed at the overall performance efficiency, it is possible to reduce the loss per each individual chain loop. The authors formulate approaches intended to lower total loss of coal in process flows. The geotechnical and organizational solutions are put forward to improve and stabilize quality of fuel used by local fuel and energy industry.

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

    OpenAIRE

    2012-01-01

    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 Cu2+ ions in a fixed-bed column configuration. The ET is formed by a 5-sensor array with Cu2+ and Ca2+-selective electrodes and electrodes with generic response to heavy-metals, plus an artificial neural network response model of the sensor's cross-response. The...

  3. Conservation laws for collisional and turbulent transport processes in toroidal plasmas with large mean flows

    Science.gov (United States)

    Sugama, H.; Nunami, M.; Nakata, M.; Watanabe, T.-H.

    2017-02-01

    A novel gyrokinetic formulation is presented by including collisional effects into the Lagrangian variational principle to yield the governing equations for background and turbulent electromagnetic fields and gyrocenter distribution functions, which can simultaneously describe classical, neoclassical, and turbulent transport processes in toroidal plasmas with large toroidal flows on the order of the ion thermal velocity. Noether's theorem modified for collisional systems and the collision operator given in terms of Poisson brackets are applied to derivation of the particle, energy, and toroidal momentum balance equations in the conservative forms, which are desirable properties for long-time global transport simulation.

  4. Coupled Simulation of Flow and Thermal Field of Twin-Roll Strip Casting Process

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The first micro-segregation under conditions of twin roll strip casting was simulated. The relationship between the temperature and solid fraction in the mushy zone was given. The temperatures such as ZDT, LIT were got from this simulation. Then using the turbulent model, the flow field and thermal field in the pool of twin-roll strip caster was simulated. The speed and temperature at different casting speed was given, and the results were also explained. By these two simulations, the appropriate casting speed can be found. These simulations can provide effective data for controlling the twin-roll strip casting process.

  5. Numerical Simulation of the Air Jet Flow Field in the Melt Blowing Process

    Institute of Scientific and Technical Information of China (English)

    CHEN Ting; HUANG Xiu-bao

    2002-01-01

    The theoretical model of the flow field of the dual slot die in melt blowing process is founded. The model is solved numerically with finite difference method. The distributions of the air velocity component in x direction along x-axis and y-axis and the air temperature distributions along x-axis and y-axis are obtained via numerical computation. The computation results coincide with the experimental data given by Harpham and Shambaugh. The distributions of the air velocity and air temperature are introduced into the air drag model of melt blowing. The model prediction of the fiber diameter agrees with the experimental data well.

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

    Science.gov (United States)

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

    2014-10-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-08-15

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

  8. Finite element simulation of dynamic wetting flows as an interface formation process

    KAUST Repository

    Sprittles, J.E.

    2013-01-01

    A mathematically challenging model of dynamic wetting as a process of interface formation has been, for the first time, fully incorporated into a numerical code based on the finite element method and applied, as a test case, to the problem of capillary rise. The motivation for this work comes from the fact that, as discovered experimentally more than a decade ago, the key variable in dynamic wetting flows - the dynamic contact angle - depends not just on the velocity of the three-phase contact line but on the entire flow field/geometry. Hence, to describe this effect, it becomes necessary to use the mathematical model that has this dependence as its integral part. A new physical effect, termed the \\'hydrodynamic resist to dynamic wetting\\', is discovered where the influence of the capillary\\'s radius on the dynamic contact angle, and hence on the global flow, is computed. The capabilities of the numerical framework are then demonstrated by comparing the results to experiments on the unsteady capillary rise, where excellent agreement is obtained. Practical recommendations on the spatial resolution required by the numerical scheme for a given set of non-dimensional similarity parameters are provided, and a comparison to asymptotic results available in limiting cases confirms that the code is converging to the correct solution. The appendix gives a user-friendly step-by-step guide specifying the entire implementation and allowing the reader to easily reproduce all presented results, including the benchmark calculations. © 2012 Elsevier Inc.

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

    CERN Document Server

    Sprittles, James

    2012-01-01

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

  10. Mathematical modelling of flow and transport processes in tissue engineering bioreactors

    Science.gov (United States)

    Waters, Sarah; Pearson, Natalie; Oliver, James; Shipley, Rebecca

    2014-11-01

    To artificially engineer tissues numerous biophysical and biochemical processes must be integrated to produce tissues with the desired in vivo properties. Tissue engineering bioreactors are cell culture systems which aim to mimic the in vivo environment. We consider a hollow fibre membrane bioreactor (HFMB), which utilises fluid flow to enhance the delivery of growth factors and nutrients to, and metabolite removal from, the cells, as well as provide appropriate mechanical stimuli to the cells. Biological tissues comprise a wide variety of interacting components, and multiphase models provide a natural framework to investigate such interactions. We present a suite of mathematical models (capturing different experimental setups) which consider the fluid flow, solute transport, and cell yield and distribution within a HFMB. The governing equations are simplified by exploiting the slender geometry of the bioreactor system, so that, e.g., lubrication theory may be used to describe flow in the lumen. We interrogate the models to illustrate typical behaviours of each setup in turn, and highlight the dependence of results on key experimentally controllable parameter values. Once validated, such models can be used to inform and direct future experiments.

  11. A Novel Mechanism for TRF of Plant-wide Material Flows in Process Industry MES

    Institute of Scientific and Technical Information of China (English)

    朱炜; 朱峰; 荣冈

    2014-01-01

    This paper is standing on the recent viewpoint originated from relevant industrial practices that well or-ganized tracing, representing and feedback (TRF) mechanism of material-flow information is crucial for system utility and usability of manufacturing execution systems (MES), essentially, for activities on the side of multi-level decision making and optimization mainly in the planning and scheduling. In this paper, we investigate a key issue emphasized on a route of multi-level information evolution on the side of large-scale feedback, where material-flow states could evolve from the measuring data (local states) to networked event-type information cells (global states) and consequently to the key performance indicators (KPI) type information (gross states). Importantly, with adapta-bilities to frequent structural dynamics residing in running material flows, this evolving route should be modeled as a suit of sophisticated mechanism for large-scale dynamic states tracking and representing so as to upgrade accu-racy and usability of the feedback information in MES. To clarify inherent complexities of this evolving route, the investigated issue is demonstrated from extended process systems engineering (PSE) point of view, and the TRF principles of the multi-level feedback information (states) are highlighted under the multi-scale methodology. As the main contribution, a novel mechanism called TRF modeling mechanism is introduced.

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

    Directory of Open Access Journals (Sweden)

    Wenhui Shi

    2014-01-01

    Full Text Available An improved method based on reverse flow injection is proposed for determining sulfate concentration in the wet-process of phosphoric acid (WPA. The effect of reagent composition, flow rate, temperature, acid concentration, length of the reaction coil, and linear response range on the flow system is discussed in detail. Optimal conditions are established for determining sulfate in the WPA samples. Baseline drift is avoided by a periodic washing step with EDTA in an alkaline medium. A linear response is observed within a range of 20 - 360 mg L-1, given by the equation A = 0.0020C (mg L-1 + 0.0300, R² = 0.9991. The detection limit of the proposed method for sulfate analysis is 3 mg L-1, and the relative standard deviation (n = 12 of sulfate absorbance peak is less than 1.60%. This method has a rate of up to 29 samples per hour, and the results compare well with those obtained with gravimetric method.

  13. Investigation on transient flow of a centrifugal charging pump in the process of high pressure safety injection

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fan, E-mail: zhangfan4060@gmail.com; Yuan, Shouqi; Fu, Qiang; Tao, Yi

    2015-11-15

    Highlights: • The transient flow characteristics of the charging pump with the first stage impeller in the HPSI process have been investigated numerically by CFD. • The hydraulic performance of the charging pump during the HPSI are discussed, andthe absolute errors between the simulated and measured results are analyzed in the paper. • Pressure fluctuation in the impeller and flow pattern in the impeller were studied in the HPSI process. It is influenced little at the beginning of the HPSI process while fluctuates strongly in the end of the HPSI process. - Abstract: In order to investigate the transient flow characteristics of the centrifugal charging pump during the transient transition process of high pressure safety injection (HPSI) from Q = 148 m{sup 3}/h to Q = 160 m{sup 3}/h, numerical simulation and experiment are implemented in this study. The transient flow rate, which is the most important factor, is obtained from the experiment and works as the boundary condition to accurately accomplish the numerical simulation in the transient process. Internal characteristics under the variable operating conditions are analyzed through the transient simulation. The results shows that the absolute error between the simulated and measured heads is less than 2.26% and the absolute error between the simulated and measured efficiency is less than 2.04%. Pressure fluctuation in the impeller is less influenced by variable flow rate in the HPSI process, while flow pattern in the impeller is getting better and better with the flow rate increasing. As flow rate increases, fluid blocks on the tongue of the volute and it strikes in this area at large flow rate. Correspondingly, the pressure fluctuation is intense and vortex occurs gradually during this period, which obviously lowers the efficiency of the pump. The contents of the current work can provide references for the design optimization and fluid control of the pump used in the transient process of variable operating

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

    Science.gov (United States)

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

    2000-01-01

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

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

    Science.gov (United States)

    Capecelatro, Jesse Samuel

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

  16. Relation among C-curve characterization diagrams

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    As three control points are fixed and the fourth control point varies, the planar cubic C-curve may take on a loop, a cusp, or zero to two inflection points, depending on the position of the moving point. The plane can, therefore, be partitioned into regions labelled according to the characterization of the curve when the fourth point is in each region. This partitioned plane is called a "characterization diagram". By moving one of the control points but fixing the rest, one can induce different characterization diagrams. In this paper, we investigate the relation among all different characterization diagrams of cubic C-curves based on the singularity conditions proposed by Yang and Wang (2004). We conclude that, no matter what the C-curve type is or which control point varies, the characterization diagrams can be obtained by cutting a common 3D characterization space with a corresponding plane.

  17. Covariant diagrams for one-loop matching

    CERN Document Server

    Zhang, Zhengkang

    2016-01-01

    We present a diagrammatic formulation of recently-revived covariant functional approaches to one-loop matching from an ultraviolet (UV) theory to a low-energy effective field theory. Various terms following from a covariant derivative expansion (CDE) are represented by diagrams which, unlike conventional Feynman diagrams, involve gauge-covariant quantities and are thus dubbed "covariant diagrams." The use of covariant diagrams helps organize and simplify one-loop matching calculations, which we illustrate with examples. Of particular interest is the derivation of UV model-independent universal results, which reduce matching calculations of specific UV models to applications of master formulas. We show how such derivation can be done in a more concise manner than the previous literature, and discuss how additional structures that are not directly captured by existing universal results, including mixed heavy-light loops, open covariant derivatives, and mixed statistics, can be easily accounted for.

  18. Revised Diagnostic Diagrams for Planetary Nebulae

    CERN Document Server

    Riesgo, H

    2006-01-01

    Diagnostic diagrams of electron density - excitation for a sample of 613 planetary nebulae are presented. The present extensive sample allows the definition of new statistical limits for the distribution of planetary nebulae in the log [Ha/[SII

  19. Phase diagram to design passive nanostructures

    CERN Document Server

    Lee, Jeng Yi

    2015-01-01

    A phase diagram, defined by the amplitude square and phase of scattering coefficients for absorption cross-section in each individual channel, is introduced as a universal map on the electromagnetic properties for passive scatterers. General physical bounds are naturally revealed based on the intrinsic power conservation in a passive scattering system, entailing power competitions among scattering, absorption, and extinction. Exotic scattering and absorption phenomena, from resonant scattering, invisible cloaking, coherent perfect absorber, and subwavelength superscattering can all be illustrated in this phase diagram. With electrically small core-shell scatterers as an example, we demonstrate a systematic method to design field-controllable structures based on the allowed trajectories in the phase diagram. The proposed phase diagram not only provides a simple tool to design optical devices but also promotes a deep understanding on Mie's scattering theory.

  20. Effects of flow scarcity on leaf-litter processing under oceanic climate conditions in calcareous streams.

    Science.gov (United States)

    Martínez, Aingeru; Pérez, Javier; Molinero, Jon; Sagarduy, Mikel; Pozo, Jesús

    2015-01-15

    Although temporary streams represent a high proportion of the total number and length of running waters, historically the study of intermittent streams has received less attention than that of perennial ones. The goal of the present study was to assess the effects of flow cessation on litter decomposition in calcareous streams under oceanic climate conditions. For this, leaf litter of alder was incubated in four streams (S1, S2, S3 and S4) with different flow regimes (S3 and S4 with zero-flow periods) from northern Spain. To distinguish the relative importance and contribution of decomposers and detritivores, fine- and coarse-mesh litter bags were used. We determined processing rates, leaf-C, -N and -P concentrations, invertebrate colonization in coarse bags and benthic invertebrates. Decomposition rates in fine bags were similar among streams. In coarse bags, only one of the intermittent streams, S4, showed a lower rate than that in the other ones as a consequence of lower invertebrate colonization. The material incubated in fine bags presented higher leaf-N and -P concentrations than those in the coarse ones, except in S4, pointing out that the decomposition in this stream was driven mainly by microorganisms. Benthic macroinvertebrate and shredder density and biomass were lower in intermittent streams than those in perennial ones. However, the bags in S3 presented a greater amount of total macroinvertebrates and shredders comparing with the benthos. The most suitable explanation is that the fauna find a food substrate in bags less affected by calcite precipitation, which is common in the streambed at this site. Decomposition rate in coarse bags was positively related to associated shredder biomass. Thus, droughts in streams under oceanic climate conditions affect mainly the macroinvertebrate detritivore activity, although macroinvertebrates may show distinct behavior imposed by the physicochemical properties of water, mainly travertine precipitation, which can

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

    Directory of Open Access Journals (Sweden)

    Ekaterina SIZOVA

    2009-01-01

    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.

  2. QCD Phase Diagram with Imaginary Chemical Potential

    Directory of Open Access Journals (Sweden)

    Nakamura Atsushi

    2012-02-01

    Full Text Available We report our recent results on the QCD phase diagram obtained from the lattice QCD simulation. The location of the phase boundary between hadronic and QGP phases in the two-flavor QCD phase diagram is investigated. The imaginary chemical potential approach is employed, which is based on Monte Carlo simulations of the QCD with imaginary chemical potential and analytic continuation to the real chemical potential region.

  3. Beyond Feynman Diagrams (1/3)

    CERN Document Server

    CERN. Geneva

    2013-01-01

    For decades the central theoretical tool for computing scattering amplitudes has been the Feynman diagram. However, Feynman diagrams are just too slow, even on fast computers, to be able to go beyond the leading order in QCD, for complicated events with many jets of hadrons in the final state. Such events are produced copiously at the LHC, and constitute formidable backgrounds to many searches for new physics. Over the past few years, alternative methods that go beyond ...

  4. Atomic energy levels and Grotrian diagrams

    CERN Document Server

    Bashkin, Stanley

    1975-01-01

    Atomic Energy Levels and Grotrian Diagrams, Volume I: Hydrogen I - Phosphorus XV presents diagrams of various elements that show their energy level and electronic transitions. The book covers the first 15 elements according to their atomic number. The text will be of great use to researchers and practitioners of fields such as astrophysics that requires pictorial representation of the energy levels and electronic transitions of elements.

  5. Random Young diagrams in a Rectangular Box

    DEFF Research Database (Denmark)

    Beltoft, Dan; Boutillier, Cédric; Enriquez, Nathanaël

    We exhibit the limit shape of random Young diagrams having a distribution proportional to the exponential of their area, and confined in a rectangular box. The Ornstein-Uhlenbeck bridge arises from the fluctuations around the limit shape.......We exhibit the limit shape of random Young diagrams having a distribution proportional to the exponential of their area, and confined in a rectangular box. The Ornstein-Uhlenbeck bridge arises from the fluctuations around the limit shape....

  6. Towards a Metropolitan Fundamental Diagram Using Travel Survey Data.

    Science.gov (United States)

    Wang, Kai; Levinson, David M

    2016-01-01

    Using travel diary data from 2000-2001 and 2010-2012 this research examines fundamental traffic relationships at the metropolitan level. The results of this paper can help to explain the causes of some traffic phenomena. Network average speed by time of day can be explained by trip length and cumulative number of vehicles on the road. A clockwise hysteresis loop is found in the Metropolitan Fundamental Diagram in the morning period and a reverse process happens in the afternoon.

  7. Reading fitness landscape diagrams through HSAB concepts

    Energy Technology Data Exchange (ETDEWEB)

    Vigneresse, Jean-Louis, E-mail: jean-louis.vigneresse@univ-lorraine.fr

    2014-10-31

    Highlights: • Qualitative information from HSAB descriptors. • 2D–3D diagrams using chemical descriptors (χ, η, ω, α) and principles (MHP, mEP, mPP). • Estimate of the energy exchange during reaction paths. • Examples from complex systems (geochemistry). - Abstract: Fitness landscapes are conceived as range of mountains, with local peaks and valleys. In terms of potential, such topographic variations indicate places of local instability or stability. The chemical potential, or electronegativity, its value changed of sign, carries similar information. In addition to chemical descriptors defined through hard-soft acid-base (HSAB) concepts and computed through density functional theory (DFT), the principles that rule chemical reactions allow the design of such landscape diagrams. The simplest diagram uses electrophilicity and hardness as coordinates. It allows examining the influence of maximum hardness or minimum electrophilicity principles. A third dimension is introduced within such a diagram by mapping the topography of electronegativity, polarizability or charge exchange. Introducing charge exchange during chemical reactions, or mapping a third parameter (f.i. polarizability) reinforces the information carried by a simple binary diagram. Examples of such diagrams are provided, using data from Earth Sciences, simple oxides or ligands.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-08-01

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-06-01

    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.

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

    Directory of Open Access Journals (Sweden)

    Shaunak Chakrabartty

    2014-05-01

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

  11. CFD study of flow-diffusion process in Y-shape micromixer

    Institute of Scientific and Technical Information of China (English)

    陈卓; 张睿琦; 王晓娜

    2016-01-01

    A CFD simulation was carried out to investigate the mixing process in a Y-shape micromixer with the software Fluent 6.3. The definition of the “diffusion angle” is proposed to describe the molecular diffusion process associated with the flow at low Reynolds number. The linear relationship between the diffusion angle and the Peclet number (Pe) is determined by both theoretical analysis and numerical simulation. Moreover, the simulation results reveal that the diffusion angle is only related to the Peclet number whilst it is irrelevant to the changes ofRe (Reynolds number) andSc (Schmidt number). The range of Peclet number and Reynolds number for experimental measurement are also suggested asPe≤10000 andRe≤10.

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

    Science.gov (United States)

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

    2015-09-01

    Groundwater chemistry and isotopic data from 40 production wells in the Atemajac and Toluquilla valleys, located in and around the Guadalajara metropolitan area, were determined to develop a conceptual model of groundwater flow processes and mixing. Stable water isotopes (δ2H, δ18O) were used to trace hydrological processes and tritium (3H) to evaluate the relative contribution of modern water in samples. Multivariate analysis including cluster analysis and principal component analysis were used to elucidate distribution patterns of constituents and factors controlling groundwater chemistry. Based on this analysis, groundwater was classified into four groups: cold groundwater, hydrothermal groundwater, polluted groundwater and mixed groundwater. Cold groundwater is characterized by low temperature, salinity, and Cl and Na concentrations and is predominantly of Na-HCO3-type. It originates as recharge at "La Primavera" caldera and is found predominantly in wells in the upper Atemajac Valley. Hydrothermal groundwater is characterized by high salinity, temperature, Cl, Na and HCO3, and the presence of minor elements such as Li, Mn and F. It is a mixed-HCO3 type found in wells from Toluquilla Valley and represents regional flow circulation through basaltic and andesitic rocks. Polluted groundwater is characterized by elevated nitrate and sulfate concentrations and is usually derived from urban water cycling and subordinately from agricultural return flow. Mixed groundwaters between cold and hydrothermal components are predominantly found in the lower Atemajac Valley. Twenty-seven groundwater samples contain at least a small fraction of modern water. The application of a multivariate mixing model allowed the mixing proportions of hydrothermal fluids, polluted waters and cold groundwater in sampled water to be evaluated. This study will help local water authorities to identify and dimension groundwater contamination, and act accordingly. It may be broadly applicable to

  13. Cloning Voronoi Diagrams via Retroactive Data Structures

    CERN Document Server

    Dickerson, Matthew T; Goodrich, Michael T

    2010-01-01

    We address the problem of replicating a Voronoi diagram $V(S)$ of a planar point set $S$ by making proximity queries, which are of three possible (in decreasing order of information content): 1. the exact location of the nearest site(s) in $S$; 2. the distance to and label(s) of the nearest site(s) in $S$; 3. a unique label for every nearest site in $S$. We provide algorithms showing how queries of Type 1 and Type 2 allow an exact cloning of $V(S)$ with $O(n)$ queries and $O(n \\log^2 n)$ processing time. We also prove that queries of Type 3 can never exactly clone $V(S)$, but we show that with $O(n \\log\\frac{1}{\\epsilon})$ queries we can construct an $\\epsilon$-approximate cloning of $V(S)$. In addition to showing the limits of nearest-neighbor database security, our methods also provide one of the first natural algorithmic applications of retroactive data structures.

  14. Influence of the Constitutive Flow Law in FEM Simulation of the Radial Forging Process

    Directory of Open Access Journals (Sweden)

    Olivier Pantalé

    2013-01-01

    Full Text Available Radial forging is a widely used forming process for manufacturing hollow products in transport industry. As the deformation of the workpiece, during the process, is a consequence of a large number of high-speed strokes, the Johnson-Cook constitutive law (taking into account the strain rate seems to be well adapted for representing the material behavior even if the process is performed under cold conditions. But numerous contributions concerning radial forging analysis, in the literature, are based on a simple elastic-plastic formulation. As far as we know, this assumption has yet not been validated for the radial forging process. Because of the importance of the flow law in the effectiveness of the model, our purpose in this paper is to analyze the influence of the use of an elastic-viscoplastic formulation instead of an elastic-plastic one for modeling the cold radial forging process. In this paper we have selected two different laws for the simulations: the Johnson-Cook and the Ludwik ones, and we have compared the results in terms of forging force, product's thickness, strains, stresses, and CPU time. For the presented study we use an AISI 4140 steel, and we denote a fairly good agreement between the results obtained using both laws.

  15. An Excel Macro to Plot the HFE-Diagram to Identify Sea Water Intrusion Phases.

    Science.gov (United States)

    Giménez-Forcada, Elena; Sánchez San Román, F Javier

    2015-01-01

    A hydrochemical facies evolution diagram (HFE-D) is a multirectangular diagram, which is a useful tool in the interpretation of sea water intrusion processes. This method note describes a simple method for generating an HFE-D plot using the spreadsheet software package, Microsoft Excel. The code was applied to groundwater from the alluvial coastal plain of Grosseto (Tuscany, Italy), which is characterized by a complex salinization process in which sea water mixes with sulfate or bicarbonate recharge water.

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

    Energy Technology Data Exchange (ETDEWEB)

    Glenn A. Shirey; David J. Akers

    2005-12-31

    With the increasing use of screen-bowl centrifuges in today's fine coal cleaning circuits, a significant amount of low-ash, high-Btu coal can be lost during the dewatering step due to the difficulty in capturing coal of this size consist (< 100 mesh or 0.15mm). The GranuFlow{trademark} technology, developed and patented by an in-house research group at DOE-NETL, involves the addition of an emulsified mixture of high-molecular-weight hydrocarbons to a slurry of finesized coal before cleaning and/or mechanical dewatering. The binder selectively agglomerates the coal, but not the clays or other mineral matter. In practice, the binder is applied so as to contact the finest possible size fraction first (for example, froth flotation product) as agglomeration of this fraction produces the best result for a given concentration of binder. Increasing the size consist of the fine-sized coal stream reduces the loss of coal solids to the waste effluent streams from the screen bowl centrifuge circuit. In addition, the agglomerated coal dewaters better and is less dusty. The binder can also serve as a flotation conditioner and may provide freeze protection. The overall objective of the project is to generate all necessary information and data required to commercialize the GranuFlow{trademark} Technology. The technology was evaluated under full-scale operating conditions at three commercial coal preparation plants to determine operating performance and economics. The handling, storage, and combustion properties of the coal produced by this process were compared to untreated coal during a power plant combustion test.

  17. Experimental investigation on chill-down process of cryogenic flow line

    Science.gov (United States)

    Jin, Lingxue; Park, Changgi; Cho, Hyokjin; Lee, Cheonkyu; Jeong, Sangkwon

    2016-10-01

    This paper describes the cryogenic chill-down experiments that are conducted on a 12.7 mm outer diameter, 1.25 mm wall thickness and 7 m long stainless steel horizontal pipe with liquid nitrogen (LN2). The pipe is vacuum insulated during the experiment to minimize the heat leak from room temperature and to enable one to numerically simulate the process easily. The temperature and the pressure profiles of the chill-down line are obtained at the location which is 5.5 m in a distance from the pipe inlet. The mass flux range is approximately from 19 kg/m2 s to 49 kg/m2 s, which corresponds to the Reynolds numbers range from 1469 to 5240. The transient histories of temperature, pressure and mass flow rate during the line chill-down process are monitored, and the heat transfer coefficient and the heat flux are computed by an inverse problem solving method. The amplitude of the pressure oscillation and the oscillating period become larger and longer at higher pressure conditions. In the low mass flux conditions, the critical heat flux in horizontal pipes is not sensitive to mass flux, and is higher than that in vertical pipes. Kutateladze's correlation with the constant coefficient, B = 0.029 , well matches the experimental data in the current work. In nucleate flow boiling regime, heat transfer coefficient, h , is proportional to (q″)n , and n is equal to 0.7.

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

    Science.gov (United States)

    Wei, Jiuan

    Understanding of multiphase flow and related heat transfer and chemical reactions are the keys to increase the productivity and efficiency in industrial processes. The objective of this thesis is to utilize the computational approaches to investigate the multiphase flow and its application in the materials processes, especially in the following two areas: directional solidification, and pyrolysis and synthesis. In this thesis, numerical simulations will be performed for crystal growth of several III-V and II-VI compounds. The effects of Prandtl and Grashof numbers on the axial temperature profile, the solidification interface shape, and melt flow are investigated. For the material with high Prandtl and Grashof numbers, temperature field and growth interface will be significantly influenced by melt flow, resulting in the complicated temperature distribution and curved interface shape, so it will encounter tremendous difficulty using a traditional Bridgman growth system. A new design is proposed to reduce the melt convection. The geometric configuration of top cold and bottom hot in the melt will dramatically reduce the melt convection. The new design has been employed to simulate the melt flow and heat transfer in crystal growth with large Prandtl and Grashof numbers and the design parameters have been adjusted. Over 90% of commercial solar cells are made from silicon and directional solidification system is the one of the most important method to produce multi-crystalline silicon ingots due to its tolerance to feedstock impurities and lower manufacturing cost. A numerical model is developed to simulate the silicon ingot directional solidification process. Temperature distribution and solidification interface location are presented. Heat transfer and solidification analysis are performed to determine the energy efficiency of the silicon production furnace. Possible improvements are identified. The silicon growth process is controlled by adjusting heating power and

  19. Parallelizing flow-accumulation calculations on graphics processing units—From iterative DEM preprocessing algorithm to recursive multiple-flow-direction algorithm

    Science.gov (United States)

    Qin, Cheng-Zhi; Zhan, Lijun

    2012-06-01

    As one of the important tasks in digital terrain analysis, the calculation of flow accumulations from gridded digital elevation models (DEMs) usually involves two steps in a real application: (1) using an iterative DEM preprocessing algorithm to remove the depressions and flat areas commonly contained in real DEMs, and (2) using a recursive flow-direction algorithm to calculate the flow accumulation for every cell in the DEM. Because both algorithms are computationally intensive, quick calculation of the flow accumulations from a DEM (especially for a large area) presents a practical challenge to personal computer (PC) users. In recent years, rapid increases in hardware capacity of the graphics processing units (GPUs) provided in modern PCs have made it possible to meet this challenge in a PC environment. Parallel computing on GPUs using a compute-unified-device-architecture (CUDA) programming model has been explored to speed up the execution of the single-flow-direction algorithm (SFD). However, the parallel implementation on a GPU of the multiple-flow-direction (MFD) algorithm, which generally performs better than the SFD algorithm, has not been reported. Moreover, GPU-based parallelization of the DEM preprocessing step in the flow-accumulation calculations has not been addressed. This paper proposes a parallel approach to calculate flow accumulations (including both iterative DEM preprocessing and a recursive MFD algorithm) on a CUDA-compatible GPU. For the parallelization of an MFD algorithm (MFD-md), two different parallelization strategies using a GPU are explored. The first parallelization strategy, which has been used in the existing parallel SFD algorithm on GPU, has the problem of computing redundancy. Therefore, we designed a parallelization strategy based on graph theory. The application results show that the proposed parallel approach to calculate flow accumulations on a GPU performs much faster than either sequential algorithms or other parallel GPU

  20. A numerical analysis on generating process of intermittent debris flow surges

    Science.gov (United States)

    Arai, Muneyuki

    2016-04-01

    The generation of debris flow has some causes. This researche is on intermittent debris flow surges and due to mathematical approach of wave equation by numerical analysis. The following wave equation was obtained based on the momentum equation of shallow water. ∂η' '∂η' ∂2η' ∂3η' ∂τ' + a1η ∂ξ' - a2∂ξ'2 + a3∂ξ'3 = 0 (1) where, a1 = (3/2)c0'2, a2 = (1/2)( ) 1/c0'2 - 1/2tanθ (c0'/u0'), a3 = (1/2){ 4 2 } (2 + c0')/(2c0')- 3/2 , u0' = u0/c0, c0' = c0/vp0, c0 = √ ---- gh0cosθ, η' = η/h0, t' = tvp0/h0, ξ = ɛ1/2(x- vp0t), τ = ɛ3/2t, ξ' = ξ/h0 = ɛ1/2(x' - t'), τ' = ɛ3/2t', u0, h0 : velocity, depth of steady uniform flow, x : axis of flow direction, t : time, η : variance of flow surface from depth h0, θ : slope angle of the channel, g : acceleration due to gravity, ξ, τ : the Gardner-Morikawa transformation of x axis and time, ɛ : parameter of perturbative expansion, vp0 : phase velocity, c0 : long wave velocity, '(with prime) : non-dimensional variable. η' of equation (1) changes depending on the values of a1, a2, a3 on same section of ξ' and τ', and a1, a2 and a3 are function of c0'. c0' is ratio of long wave velocity and phase velocity, and c0' = 1 when phase velocity is equal to long wave velocity. For c0' = 1, then a3 = 0, the equation (1) becomes Burgers Equation, the waves deform to a wave of wave number one with increased phase velocity on progress at time. Therefor, the wave parts from Burgers equation and becomes the one that depend on equation (1) , KdV-Burgers equation. When the new phase velocity is grater than 1.04 times c0' (long wave velocity), waveform behaves as a solitary wave. This research shows these processes by some numerical solutions of equation (1).

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

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, N.; Solomon, I.

    2010-07-01

    The geometric shape of the tools is the main factor by which an optimum technological process can be developed. In the case of extrusion process the strain distribution and other important variables that influence material structure, such as hydrostatic stress, are strongly dependent on the geometry of the die. Careful design of the extrusion die profile can therefore control the product structure and can be used to minimise the amount of inhomogeneity imparted into the product. A possibility to minimise the amount of product inhomogeneity is the using of a flat die with a fillet radius in front to the bearing surface with leads to a minimum dead zone and consequently to a minimum friction at billet-container interface. In the case of aluminium alloy type 2024, for an extrusion ratio of R=8.5, good results were obtained with a fillet radius of 3.0 mm. The experimental data have been used for the finite element numerical simulation of the extrusion process. The data obtained by numerical simulation with FORGE2 programme confirm the theoretical and experimental outcomes. The aim of this paper is to study the influence of such flat die on the material flow during direct extrusion process and consequently on extruded product microstructure and mechanical properties. (Author).

  2. A Novel Particle Swarm Optimization for Flow Shop Scheduling with Fuzzy Processing Time

    Institute of Scientific and Technical Information of China (English)

    NIU Qun; GU Xing-sheng

    2008-01-01

    Since in most practical cases the processing time of scheduling is not deterministic,flow shop scheduling model with fuzzy processing time is established.It is assumed that the processing times of jobs on the machines are described by triangular fuzzy sets.In order to find a sequence that minimizes the mean makespan and the spread of the makespan,Lee and Li fuzzy ranking method is adopted and modified to solve the problem.Particle swarm optimization (PSO) is a population-based stochyastic appmxilmtion aigorithm that has been applied to a wide range of problems,but there is little reported in respect of application to scheduling problems because of its unsuitability for them.In the paper,PSO is redefined and modified by introducing genetic operations such as crossover and mutation to update the particles,which is called GPSO and successfully employed to solve the formulated problem.A series of benchmarks with fuzzy processing time are used to verify GPSO.Extensive experiments show the feasibility and effectiveness of the proposed method.

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

    Science.gov (United States)

    Gokce, Ali

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

  4. Drying and Heating Modelling of Granular Flow: Application to the Mix-Asphalt Processes

    Directory of Open Access Journals (Sweden)

    L Le Guen

    2011-01-01

    Full Text Available Concrete asphalt is a hydrocarbon material that includes a mix of mineral components along with a bituminous binder. Prior to mixing, its production protocol requires drying and heating the aggregates. Generally performed in a rotary drum, these drying and heating steps within mix asphalt processes have never been studied from a physical perspective. We are thus proposing in the present paper to analyze the drying and heating mechanisms when granular materials and hot gases are involved in a co-current flow. This process step accounts for a large proportion of the overall energy consumed during hot-mix asphalt manufacturing. In the present context, the high energy cost associated with this step has encouraged developing new strategies specifically for the drying process. Applying new asphalt techniques so that an amount of moisture can be preserved in the asphalt concrete appears fundamental to such new strategies. This low-energy asphalt, also referred to as the "warm technique", depends heavily on a relevant prediction of the actual moisture content inside asphalt concrete during the mixing step. The purpose of this paper is to present a physical model dedicated to the evolution in temperature and moisture of granular solids throughout the drying and heating steps carried out inside a rotary drum. An initial experimental campaign to visualize inside a drum at the pilot scale (i.e. 1/3 scale has been carried out in order to describe the granular flow and establish the necessary physical assumptions for the drying and heating model. Energy and mass balance equations are solved by implementing an adequate heat and mass transfer coupling, yielding a 1D model from several parameters that in turn drives the physical modeling steps. Moreover, model results will be analyzed and compared to several measurements performed in an actual asphalt mix plant at the industrial scale (i.e. full scale.

  5. Seasonality of low flows and dominant processes in the Rhine River

    NARCIS (Netherlands)

    Tongal, H.; Demirel, M.C.; Booij, M.J.

    2013-01-01

    Low flow forecasting is crucial for sustainable cooling water supply and planning of river navigation in the Rhine River. The first step in reliable low flow forecasting is to understand the characteristics of low flow. In this study, several methods are applied to understand the low flow characteri

  6. 浅谈超声心动图检测正常胎儿动脉导管血流频谱的定量研究%Quantitative Study on the Detection of Ultrasonic Beckoning Diagram on Blood Flow Spectrum of Fetal Ductus Arteriosus

    Institute of Scientific and Technical Information of China (English)

    朱福海; 彭维绮; 蔡华

    2015-01-01

    目的:探究超声心动图检测在正常胎儿动脉导管血流频谱定量研究中的应用意义。方法:择取本院2012年9月-2014年9月收治的行产前超声检查并分娩的156例正常单胎为研究对象,应用彩色多普勒超声心动图,检测正常胎儿动脉导管,详细观察胎儿各个发育时期动态变化规律。结果:156例正常胎儿均获取相对清晰的动脉导管二维超声心动图与血流频谱图,动脉导管脉冲多普勒频谱呈双峰型;经由回归性分析发现,孕龄与AT、PFVd、PFVs呈正相关(P<0.05)。结论:超声心动图检测在正常胎儿动脉导管血流频谱定量研究中具有至关重要的应用意义,可提供胎儿循环系统生理信息,及早评估胎儿风险值,并及时采取干预措施,临床上应引起足够重视。%Objective:To explore the application of detection of ultrasonic beckoning diagram on blood flow spectrum of fetal ductus arteriosus. Method:To select 156 patients with normal singleton birth for prenatal ultrasonography in our hospital from September 2012 to September 2014 as the research objects,application of color doppler ultrasound beckoning diagram,detection of normal fetal ductus arteriosus,variation rules of dynamic observation of the fetal period with different development. Result:156 patients with normal fetal ductus were obtain two-dimensional ultrasound relatively clear beckoning with color Doppler flow spectrum,transcatheter arterial pulse doppler spectrum showed a bimodal pattern;through regression analysis,related to gestational age and AT,PFVd,PFVs positive(P<0.05). Conclusion:The application of graph is of vital significance of beckoning detected in normal fetal ductus arteriosus blood flow spectrum in quantitative study of ultrasound,fetal circulation system can provide physiological information,early assessment of fetal risk value,timely intervention,clinical attention should be paid.

  7. TIME-TEMPERATURE-TRANSFORMATION (TTT) DIAGRAMS FOR FUTURE WASTE COMPOSITIONS

    Energy Technology Data Exchange (ETDEWEB)

    Billings, A.; Edwards, T.

    2010-07-08

    As a part of the Waste Acceptance Product Specifications (WAPS) for Vitrified High-Level Waste Forms defined by the Department of Energy - Office of Environmental Management, the waste form stability must be determined for each of the projected high-level waste (HLW) types at the Savannah River Site (SRS). Specifically, WAPS 1.4.1 requires the glass transition temperature (T{sub g}) to be defined and time-temperature-transformation (TTT) diagrams to be developed. The T{sub g} of a glass is an indicator of the approximate temperature where the supercooled liquid converts to a solid on cooling or conversely, where the solid begins to behave as a viscoelastic solid on heating. A TTT diagram identifies the crystalline phases that can form as a function of time and temperature for a given waste type or more specifically, the borosilicate glass waste form. In order to assess durability, the Product Consistency Test (PCT) was used and the durability results compared to the Environmental Assessment (EA) glass. The measurement of glass transition temperature and the development of TTT diagrams have already been performed for the seven Defense Waste Processing Facility (DWPF) projected compositions as defined in the Waste Form Compliance Plan (WCP) and in SRNL-STI-2009-00025. Additional phase transformation information exists for other projected compositions, but overall these compositions did not cover composition regions estimated for future waste processing. To develop TTT diagrams for future waste types, the Savannah River National Laboratory (SRNL) fabricated two caches of glass from reagent grade oxides to simulate glass compositions which would be likely processed with and without Al dissolution. These were used for glass transition temperature measurement and TTT diagram development. The glass transition temperatures of both glasses were measured using differential scanning calorimetry (DSC) and were recorded to be 448 C and 452 C. Using the previous TTT diagrams as

  8. Semantic annotation of requirements for automatic UML class diagram generation

    CERN Document Server

    Amdouni, Soumaya; Bouabid, Sondes

    2011-01-01

    The increasing complexity of software engineering requires effective methods and tools to support requirements analysts' activities. While much of a company's knowledge can be found in text repositories, current content management systems have limited capabilities for structuring and interpreting documents. In this context, we propose a tool for transforming text documents describing users' requirements to an UML model. The presented tool uses Natural Language Processing (NLP) and semantic rules to generate an UML class diagram. The main contribution of our tool is to provide assistance to designers facilitating the transition from a textual description of user requirements to their UML diagrams based on GATE (General Architecture of Text) by formulating necessary rules that generate new semantic annotations.

  9. Numerical Tools for Multicomponent, Multiphase, Reactive Processes: Flow of CO{sub 2} in Porous Medium

    Energy Technology Data Exchange (ETDEWEB)

    Khattri, Sanjay Kumar

    2006-07-01

    The thesis is concerned with numerically simulating multicomponent, multiphase, reactive transport in heterogeneous porous medium. Such processes are ubiquitous, for example, deposition of green house gases, flow of hydrocarbons and groundwater remediation. Understanding such processes is important from social and economic point of view. For the success of geological sequestration, an accurate estimation of migration patterns of green-house gases is essential. Due to an ever increasing computer power, computational mathematics has become an important tool for predicting dynamics of porous media fluids. Numerical and mathematical modelling of processes in a domain requires grid generation in the domain, discretization of the continuum equations on the generated grid, solution of the formed linear or nonlinear system of discrete equations and finally visualization of the results. The thesis is composed of three chapters and eight papers. Chapter 2 presents two techniques for generating structured quadrilateral and hexahedral meshes. These techniques are called algebraic and elliptic methods. Algebraic techniques are by far the most simple and computationally efficient method for grid generation. Transfinite interpolation operators are a kind of algebraic grid generation technique. In this chapter, many transfinite interpolation operators for grid generation are derived from 1D projection operators. In this chapter, some important properties of hexahedral elements are also mentioned. These properties are useful in discretization of partial differential equations on hexahedral mesh, improving quality of the hexahedral mesh, mesh generation and visualization. Chapter 3 is about CO{sub 2} flow in porous media. In this chapter, we present the mathematical models and their discretization for capturing major physical processes associated with CO{sub 2} deposition in geological formations. Some important simulations of practical applications in 2D and 3D are presented

  10. Flow, heat transfer, and free surface shape during the optical fiber drawing process

    Science.gov (United States)

    Xiao, Zhihui

    1997-12-01

    A two-dimensional finite element model is introduced for analyzing glass and gas flows, heat transfer, and fiber formation during the optical fiber drawing process. This study consists of simulations in three different areas: the upper region, the tip region, and the whole furnace region. Conjugating the glass and gas flows and heat transfer, the shapes of an optical fiber as free surfaces in the upper neck-down and the tip regions are separately obtained by solving the coupled continuity, momentum, and energy equations. In the upper region simulation, a surface-to-surface radiation model is used for the enclosure which consists of the wall and the glass surface, and the Rosseland approximation radiation model is employed to account for the radiation effect in the glass region. In the tip region simulation, only the glass fiber region is considered and a convective heat transfer model on the fiber surface is employed to account for the energy exchange between the fiber surface and the purge gas. In the fiber, radiation in the axial direction is included. The whole furnace simulation uses a calculated fiber neck-down shape and an assumed fiber tip shape as a fixed interface and computes the convective heat transfer coefficient profile in the tip region which was used in the tip region simulation. The glass viscosity is temperature-dependent and significantly affects the fiber shape. The finite element code FIDAP is used in the study. The effects of various operating conditions such as draw speed, wall temperature distribution, and gas flow rate are studied.

  11. Visual processing of optic flow and motor control in the human posterior cingulate sulcus.

    Science.gov (United States)

    Field, David T; Inman, Laura A; Li, Li

    2015-10-01

    Previous studies have shown that the human posterior cingulate contains a visual processing area selective for optic flow (CSv). However, other studies performed in both humans and monkeys have identified a somatotopic motor region at the same location (CMA). Taken together, these findings suggested the possibility that the posterior cingulate contains a single visuomotor integration region. To test this idea we used fMRI to identify both visual and motor areas of the posterior cingulate in the same brains and to test the activity of those regions during a visuomotor task. Results indicated that rather than a single visuomotor region the posterior cingulate contains adjacent but separate motor and visual regions. CSv lies in the fundus of the cingulate sulcus, while CMA lies in the dorsal bank of the sulcus, slightly superior in terms of stereotaxic coordinates. A surprising and novel finding was that activity in CSv was suppressed during the visuomotor task, despite the visual stimulus being identical to that used to localize the region. This may provide an important clue to the specific role played by this region in the utilization of optic flow to control self-motion.

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

    Science.gov (United States)

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

    2005-08-01

    Flow cytometry analyses were used to verify the ploidy stability of Quercus suber L. somatic embryogenesis process. Leaf explants of two adult cork oak trees (QsG0 and QsG5) of the North of Portugal were inoculated on MS medium with 2,4-D and zeatin. After 3 months, calluses with embryogenic structures were isolated and transferred to fresh MS medium without growth regulators and somatic embryo evolution was followed. Morphologically normal somatic embryos (with two cotyledons) and abnormal somatic embryos (with one or three cotyledons) were used in this assay. Flow cytometry combined with propidium iodide staining was employed to estimate DNA ploidy levels and nuclear DNA content of somatic embryos and leaves from mother plants. No significant differences (P< or =0.05) were detected among embryos, and between the embryos and the mother plants. Also, after conversion of these embryos, no significant morphological differences were observed among the somatic embryo-derived plants. These results and further studies using converted plantlet leaves and embryogenic callus tissue indicate that embryo cultures and converted plantlets were stable with regard to ploidy level. As no major somaclonal variation was detected our primary goal of "true-to-type" propagation of cork oak using somatic embryogenesis was assured at this level. The estimation of the 2C nuclear DNA content for this species is similar to the previously obtained value.

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

    Science.gov (United States)

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

    2013-04-01

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

  14. A Regime Diagram for Autoignition of Homogeneous Reactant Mixtures with Turbulent Velocity and Temperature Fluctuations

    KAUST Repository

    Im, Hong G.

    2015-04-02

    A theoretical scaling analysis is conducted to propose a diagram to predict weak and strong ignition regimes for a compositionally homogeneous reactant mixture with turbulent velocity and temperature fluctuations. The diagram provides guidance on expected ignition behavior based on the thermo-chemical properties of the mixture and the flow/scalar field conditions. The analysis is an extension of the original Zeldovich’s analysis by combining the turbulent flow and scalar characteristics in terms of the characteristic Damköhler and Reynolds numbers of the system, thereby providing unified and comprehensive understanding of the physical and chemical mechanisms controlling ignition characteristics. Estimated parameters for existing experimental measurements in a rapid compression facility show that the regime diagram predicts the observed ignition characteristics with good fidelity.

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

    Science.gov (United States)

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

    2011-09-15

    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.

  16. Optimizing resource allocation and patient flow: process analysis and reorganization in three chemotherapy outpatient clinics.

    Science.gov (United States)

    Holmes, Morgan; Bodie, Kelly; Porter, Geoffrey; Sullivan, Victoria; Tarasuk, Joy; Trembley, Jodie; Trudeau, Maureen

    2010-01-01

    Optimizing human and physical resources is a major concern for cancer care decision-makers and practitioners. This issue is particularly acute in the context of ambulatory out patient chemotherapy clinics, especially when - as is the case almost everywhere in the industrialized world - the number of people requiring systemic therapy is increasing while budgets, staffing and physical space remain static. Recent initiatives at three hospital-based chemotherapy units - in Halifax, Toronto and Kingston - shed light on the value of process analysis and reorganization for using existing human and physical resources to their full potential, improving patient flow and enhancing patient satisfaction. The steps taken in these settings are broadly applicable to other healthcare settings and would likely result in similar benefits in those environments.

  17. Flow and transport processes in a macroporous subsurface-drained glacial till soil

    DEFF Research Database (Denmark)

    Villholth, Karen Grothe; Jensen, Karsten Høgh; Fredericia, Johnny

    1998-01-01

    The qualitative and quantitative effects of macropore flow and transport in an agricultural subsurface-drained glacial till soil in eastern Denmark have been investigated. Three controlled tracer experiments on individual field plots (each approximately 1000 m(2)) were carried out by surface...... was evidenced directly by the rapid (within 10 mm of water input) and abrupt chloride breakthrough in the drainage water at 1.2 m depth in two of the tracer experiments. In the third experiment, the effect of macropore transport was obvious from the rapid and relatively deep penetration of the tracer...... into the soil profile. Dye infiltration experiments in the field as well as in the laboratory supported the recognition of the dominant contribution of macropores to the infiltration and transport process. The soil matrix significantly influenced the tracer distribution by acting as a source or sink...

  18. Insights into the Impact of the Nafion Membrane Pretreatment Process on Vanadium Flow Battery Performance.

    Science.gov (United States)

    Jiang, Bo; Yu, Lihong; Wu, Lantao; Mu, Di; Liu, Le; Xi, Jingyu; Qiu, Xinping

    2016-05-18

    Nafion membranes are now the most widely used membranes for long-life vanadium flow batteries (VFBs) because of their extremely high chemical stability. Today, the type of Nafion membrane that should be selected and how to pretreat these Nafion membranes have become critical issues, which directly affects the performance and cost of VFBs. In this work, we chose the Nafion 115 membrane to investigate the effect of the pretreatment process (as received, wet, boiled, and boiled and dried) on the performance of VFBs. The relationship between the nanostructure and transport properties of Nafion 115 membranes is elucidated by wide-angle X-ray diffraction and small-angle X-ray scattering techniques. The self-discharge process, battery efficiencies, electrolyte utilization, and long-term cycling stability of VFBs with differently pretreated Nafion membranes are presented comprehensively. An online monitoring system is used to monitor the electrolyte volume that varies during the long-term charge-discharge test of VFBs. The capacity fading mechanism and electrolyte imbalance of VFBs with these Nafion 115 membranes are also discussed in detail. The optimal pretreatment processes for the benchmark membrane and practical application are synthetically selected.

  19. Experimental investigation and numerical simulation of plastic flow behavior during forward-backward-radial extrusion process

    Directory of Open Access Journals (Sweden)

    A. Farhoumand

    2016-12-01

    Full Text Available Finite element method was employed to investigate the effect of process parameters of plastic deformation behavior in Forward-Backward-Radial Extrusion (FBRE process. The result of an axisymmetric model shows that the friction between die components and the sample has a substantial effect on the material flow behavior. Although strain heterogeneity index (SHI slightly decreases with an increase in friction, large portion of the sample experiences significant strain heterogeneity. Increasing the friction factor also localizes the strain heterogeneity effect in the backward section, and spread the effect in the forward section. Decreasing the friction in the FBRE process can reduce the amount of the strain heterogeneity in the product while decreases the required punch force substantially. Furthermore, an increase in gap thickness increases the deformation in the area close to the lower punch at the expense of the area in the vicinity of the upper punch. The numerical simulation has a good agreement with the experimental results which confirms the accuracy of the proposed finite element model.

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

    Directory of Open Access Journals (Sweden)

    Norihisa Miki

    2013-03-01

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

  1. Standardizing admission and discharge processes to improve patient flow: A cross sectional study

    Directory of Open Access Journals (Sweden)

    Ortiga Berta

    2012-06-01

    Full Text Available Abstract Background The aim of this study was to evaluate how hospital capacity was managed focusing on standardizing the admission and discharge processes. Methods This study was set in a 900-bed university affiliated hospital of the National Health Service, near Barcelona (Spain. This is a cross-sectional study of a set of interventions which were gradually implemented between April and December 2008. Mainly, they were focused on standardizing the admission and discharge processes to improve patient flow. Primary administrative data was obtained from the 2007 and 2009 Hospital Database. Main outcome measures were median length of stay, percentage of planned discharges, number of surgery cancellations and median number of delayed emergency admissions at 8:00 am. For statistical bivariate analysis, we used a Chi-squared for linear trend for qualitative variables and a Wilcoxon signed ranks test and a Mann–Whitney test for non-normal continuous variables. Results The median patients’ global length of stay was 8.56 days in 2007 and 7.93 days in 2009 (p  Conclusions In conclusion, standardization of admission and discharge processes are largely in our control. There is a significant opportunity to create important benefits for increasing bed capacity and hospital throughput.

  2. Mercury mass flow in iron and steel production process and its implications for mercury emission control.

    Science.gov (United States)

    Wang, Fengyang; Wang, Shuxiao; Zhang, Lei; Yang, Hai; Gao, Wei; Wu, Qingru; Hao, Jiming

    2016-05-01

    The iron and steel production process is one of the predominant anthropogenic sources of atmospheric mercury emissions worldwide. In this study, field tests were conducted to study mercury emission characteristics and mass flows at two iron and steel plants in China. It was found that low-sulfur flue gas from sintering machines could contribute up to 41% of the total atmospheric mercury emissions, and desulfurization devices could remarkably help reduce the emissions. Coal gas burning accounted for 17%-49% of the total mercury emissions, and therefore the mercury control of coal gas burning, specifically for the power plant burning coal gas to generate electricity, was significantly important. The emissions from limestone and dolomite production and electric furnaces can contribute 29.3% and 4.2% of the total mercury emissions from iron and steel production. More attention should be paid to mercury emissions from these two processes. Blast furnace dust accounted for 27%-36% of the total mercury output for the whole iron and steel production process. The recycling of blast furnace dust could greatly increase the atmospheric mercury emissions and should not be conducted. The mercury emission factors for the coke oven, sintering machine and blast furnace were 0.039-0.047gHg/ton steel, and for the electric furnace it was 0.021gHg/ton steel. The predominant emission species was oxidized mercury, accounting for 59%-73% of total mercury emissions to air.

  3. The Semiotic Structure of Geometry Diagrams: How Textbook Diagrams Convey Meaning

    Science.gov (United States)

    Dimmel, Justin K.; Herbst, Patricio G.

    2015-01-01

    Geometry diagrams use the visual features of specific drawn objects to convey meaning about generic mathematical entities. We examine the semiotic structure of these visual features in two parts. One, we conduct a semiotic inquiry to conceptualize geometry diagrams as mathematical texts that comprise choices from different semiotic systems. Two,…

  4. Simulation and Optimization of Air Cargo Export Handling System Based on Physical Flow Diagram and Witness Software%基于实体流程图和Witness仿真的航空货运离港系统仿真分析与优化研究

    Institute of Scientific and Technical Information of China (English)

    崔华春; 尹纯建; 贾焜; 石学刚

    2016-01-01

    The air cargo export handling operation is the most important system of the airport ground operations to airlines. And the optimization of the air cargo export handling system is crucial to improve the operation efficiency of air cargo sys-tem. Taking a typical domestic airline hub's air cargo as an example, establishes physical flow diagram based on the work flow of air cargo export handling system, which intuitively ex-hibits the flow of air cargo export handling. On this basis, the bottleneck segment resulting in the low efficiency of air cargo export handling system was obtained by simulation using the Witness software, followed by an optimization to enhance the efficiency of air cargo export handling system. This study plays a significant role to improve the overall operational effi-ciency of the air cargo export handling system. There is a great reference to many other emerging hub airport and small and medium sized airports to optimize their air cargo export handling system.%航空货运离港作业是航空公司地面作业中最重要的环节,航空公司货运离港系统的优化对提高航空货运系统的运作效率至关重要。以国内某典型枢纽机场航空货站为例,根据航空货运离港流程,利用实体流程图对航空货运离港系统流程进行建模,直观地展现货物离港的作业流程。在此基础上,运用Witness软件进行仿真,得到离港系统流程中的瓶颈环节,并对其进行优化,从而提高了航空货运离港系统的效率。以期对其他新兴的枢纽机场以及中小型机场的航空货运离港作业有些许借鉴意义。

  5. Dangerous situations in a synchronized flow model

    Science.gov (United States)

    Jiang, Rui; Wu, Qing-Song

    2007-04-01

    This paper studies the dangerous situation (DS) in a synchronized flow model. The DS on the two branches of the fundamental diagram are investigated, respectively. It is shown that different relationship between DS probability and the density exists in the synchronized flow and in the jams. Moreover, we prove that there is no DS caused by non-stopped car although the model itself is a non-exclusion process. We classify the DS into four sub-types and study the probability of these four sub-types. The simulation result is consistent with the real traffic.

  6. Collaborative distributed sensor management and information exchange flow control for multitarget tracking using Markov decision processes

    Science.gov (United States)

    Akselrod, Dimitry; Kirubarajan, T.

    2008-04-01

    In this paper, we consider the problem of collaborative management of uninhabited aerial vehicles (UAVs) for multitarget tracking. In addition to providing a solution to the problem of controlling individual UAVs, we present a method for controlling the information flow among them. The latter provides a solution to one of the main problems in decentralized tracking, namely, distributed information transfer and fusion among the participating platforms. The problem of decentralized cooperative control considered in this paper is an optimization of the information obtained by a number of UAVs, carrying out surveillance over a region, which includes a number of confirmed and suspected moving targets with the goal to track confirmed targets and detects new targets in the area. Each UAV has to decide on the most optimal path with the objective to track as many targets as possible, maximizing the information obtained during its operation with the maximum possible accuracy at the lowest possible cost. Limited communication between UAVs and uncertainty in the information obtained by each UAV regarding the location of the ground targets are addressed in the problem formulation. In order to handle these issues, the problem is presented as an operation of a group of decision makers. Markov Decision Processes (MDPs) are incorporated into the solution. A decision mechanism for collaborative distributed data fusion provides each UAV with the required data for the fusion process while substantially reducing redundancy in the information flow in the overall system. We consider a distributed data fusion system consisting of UAVs that are decentralized, heterogenous, and potentially unreliable. Simulation results are presented on a representative multisensor-multitarget tracking problem.

  7. Visualizing Metrics on Areas of Interest in Software Architecture Diagrams

    NARCIS (Netherlands)

    Byelas, Heorhiy; Telea, Alexandru; Eades, P; Ertl, T; Shen, HW

    2009-01-01

    We present a new method for the combined visualization of software architecture diagrams, Such as UML class diagrams or component diagrams, and software metrics defined on groups of diagram elements. Our method extends an existing rendering technique for the so-called areas of interest in system arc

  8. Fishbone Diagrams: Organize Reading Content with a "Bare Bones" Strategy

    Science.gov (United States)

    Clary, Renee; Wandersee, James

    2010-01-01

    Fishbone diagrams, also known as Ishikawa diagrams or cause-and-effect diagrams, are one of the many problem-solving tools created by Dr. Kaoru Ishikawa, a University of Tokyo professor. Part of the brilliance of Ishikawa's idea resides in the simplicity and practicality of the diagram's basic model--a fish's skeleton. This article describes how…

  9. Relationship between effective solar radiation and sap flow process during an entire growing season in Western Mountains of Beijing

    Institute of Scientific and Technical Information of China (English)

    Xu Jun-jiang; Ma Lv-yi

    2007-01-01

    In order to explore the relationship between the time processes of solar radiation and sap flow, sap flow velocity (SFV) of Platycladus orientalis and Pinus tabulaeformis,effective solar radiation (ESR) and other environmental factors wore synchronously monitored for one year in the Beijing Western Mountains by using a thermal dissipation probe (TDP) system and an automatic weather station. Results showed significant differences between changes in diurnal characteristics of ESR and sap flow in sunny days during three seasons. Starting times of sap flow occurred generally 1. 5-3 hours later than those of solar radiation and there were small differences between Platycladus orientalis and Pinus tabulaeformis. But peak times and stopping times of sap flow varied considerably with large contrasts in ESR. The duration of sap flow showed clear differences among the seasons owing to the variable rhythms of climate factors in Beijing. Fluctuation amplitude in the duration of sap flow remained relatively stable during the autumn but changed greatly during spring and summer. Changes in diurnal sap flow velocity of both Platycladus orientalis and Pinus tabulaeformis were about 0-3 hours later than those of ESR but with the same configuration. The start of sap flow was mainly induced by the sudden intensification of ESR (sunrise effect). Seasonal models of SFV indicated that a cubic equation had the best fit. It Was more practical to simulate seasonal water consumption models of trees with ESR. In further investigations,these models should be optimized.

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

    DEFF Research Database (Denmark)

    Duijm, Nijs Jan; Markert, Frank

    2009-01-01

    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......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...

  11. 从UML顺序图生成状态图的一个方法%A Method for the Transformation from Sequence Diagram to Statechart Diagram

    Institute of Scientific and Technical Information of China (English)

    袁海; 李宣东; 郑国梁

    2003-01-01

    UML (Unified Modeling Language) is a visual modeling language used for specifying, visualizing, constructing,and documenting the artifacts of software systems by various diagrams. It has been widely accepted as a standard modeling language in both academic and industrial areas. UML sequence diagrams are mostly used in specifying system requirements. By representing interactions, which are arranged in time sequence,between the objects in a system,sequence diagrams can construct scenarios indicating the system's functions. A UML statechart diagram is a graph shows the sequences of states that an object or an interaction goes through during its life in response to received stimuli,together with its responses and actions. It's useful in the design stage of system development. This essay discusses the computer-aided transformation from sequence diagrams to statechart diagrams,which can offer strong support for the transfering from requirement analysis to system design in the software development process. With OCL (Object Control Language) semantic constrain,a transform algorithm is provided in the paper. And the differences with the related works are also mentioned.

  12. Phase diagram of a truncated tetrahedral model

    Science.gov (United States)

    Krcmar, Roman; Gendiar, Andrej; Nishino, Tomotoshi

    2016-08-01

    Phase diagram of a discrete counterpart of the classical Heisenberg model, the truncated tetrahedral model, is analyzed on the square lattice, when the interaction is ferromagnetic. Each spin is represented by a unit vector that can point to one of the 12 vertices of the truncated tetrahedron, which is a continuous interpolation between the tetrahedron and the octahedron. Phase diagram of the model is determined by means of the statistical analog of the entanglement entropy, which is numerically calculated by the corner transfer matrix renormalization group method. The obtained phase diagram consists of four different phases, which are separated by five transition lines. In the parameter region, where the octahedral anisotropy is dominant, a weak first-order phase transition is observed.

  13. Steam distillation extraction of ginger essential oil: Study of the effect of steam flow rate and time process

    Science.gov (United States)

    Fitriady, Muhammad Arifuddin; Sulaswatty, Anny; Agustian, Egi; Salahuddin, Aditama, Deska Prayoga Fauzi

    2017-01-01

    In Indonesia ginger was usually used as a seasoning for dishes, an ingredient for beverage and a source of herbal medicines. Beside raw usage, ginger can be processed to obtain the essential oil which has many advantages such as proven to be an active antimicrobial and having an antioxidant ability. There are a lot of methods to extract essential oil from ginger, one of which is steam distillation. The aim of the current study was to investigate the effect of variation of time process and steam flow rate in the yield on ginger essential oil steam distillation extraction process. It was found that the best operation condition was 0.35 ml/s as the steam flow rate which yields 2.43% oil. The optimum time process was predicted at 7.5 hours. The composition of the oil was varied depend on the flow rate and every flow rate has its own major component contained in the oil. Curcumene composition in the oil was increased as increased steam flow rate applied, but the composition of camphene was decreased along with the increasing steam flow rate.

  14. Partial chord diagrams and matrix models

    DEFF Research Database (Denmark)

    Andersen, Jørgen Ellegaard; Fuji, Hiroyuki; Manabe, Masahide

    spectrum. Furthermore, we consider the boundary length and point spectrum that unifies the last two types of spectra. We introduce matrix models that encode generating functions of partial chord diagrams filtered by each of these spectra. Using these matrix models, we derive partial differential equations......In this article, the enumeration of partial chord diagrams is discussed via matrix model techniques. In addition to the basic data such as the number of backbones and chords, we also consider the Euler characteristic, the backbone spectrum, the boundary point spectrum, and the boundary length...... – obtained independently by cut-and-join arguments in an earlier work – for the corresponding generating functions....

  15. The Voronoi diagram of circles made easy

    DEFF Research Database (Denmark)

    Anton, François; Mioc, Darka; Gold, Christopher

    2007-01-01

    Proximity queries among circles could be effectively answered if the Delaunay graph for sets of circles could be computed in an efficient and exact way. In this paper, we first show a necessary and sufficient condition of connectivity of the Voronoi diagram of circles. Then, we show how the Delau......Proximity queries among circles could be effectively answered if the Delaunay graph for sets of circles could be computed in an efficient and exact way. In this paper, we first show a necessary and sufficient condition of connectivity of the Voronoi diagram of circles. Then, we show how...

  16. DEPENDENCE ANALYSIS FOR UML CLASS DIAGRAMS

    Institute of Scientific and Technical Information of China (English)

    Wu Fangjun; Yi Tong

    2004-01-01

    Though Unified Modeling Language (UML) has been widely used in software development, the major problems confronted lie in comprehension and testing. Dependence analysis is an important approach to analyze, understand, test and maintain programs. A new kind of dependence analysis method for UML class diagrams is developed. A set of dependence relations is definedcorresponding to the relations among classes. Thus, the dependence graph of UML class diagram can be constructed from these dependence relations. Based on this model, both slicing and measurement coupling are further given as its two applications.

  17. Phase diagrams modified by interfacial penalties

    Directory of Open Access Journals (Sweden)

    Atanacković T.M.

    2007-01-01

    Full Text Available The conventional forms of phase diagrams are constructed without consideration of interfacial energies and they represent an impor­tant tool for chemical engineers and metallurgists. If interfacial energies are taken into consideration, it is intuitively obvious that the regions of phase equilibria must become smaller, because there is a penalty on the formation of interfaces. We investigate this phe­nomenon qualitatively for a one-dimensional model, in which the phases occur as layers rather than droplets or bubbles. The modified phase diagrams are shown in Chapters 3 and 4.

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

    Energy Technology Data Exchange (ETDEWEB)

    Meglicki, Zdzislaw, E-mail: gustav@indiana.edu [Indiana University, Office of the Vice President for Information Technology, 601 E. Kirkwood Ave., Room 116, Bloomington, IN 47405-1223 (United States)

    2011-07-04

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

  19. Low-resolution remeshing using the localized restricted voronoi diagram

    KAUST Repository

    Yan, Dongming

    2014-10-01

    A big problem in triangular remeshing is to generate meshes when the triangle size approaches the feature size in the mesh. The main obstacle for Centroidal Voronoi Tessellation (CVT)-based remeshing is to compute a suitable Voronoi diagram. In this paper, we introduce the localized restricted Voronoi diagram (LRVD) on mesh surfaces. The LRVD is an extension of the restricted Voronoi diagram (RVD), but it addresses the problem that the RVD can contain Voronoi regions that consist of multiple disjoint surface patches. Our definition ensures that each Voronoi cell in the LRVD is a single connected region. We show that the LRVD is a useful extension to improve several existing mesh-processing techniques, most importantly surface remeshing with a low number of vertices. While the LRVD and RVD are identical in most simple configurations, the LRVD is essential when sampling a mesh with a small number of points and for sampling surface areas that are in close proximity to other surface areas, e.g., nearby sheets. To compute the LRVD, we combine local discrete clustering with a global exact computation. © 1995-2012 IEEE.

  20. Electrodynamic metaphors: communicating particle physics with Feynman diagrams

    Directory of Open Access Journals (Sweden)

    Pietroni Massimo

    2002-03-01

    Full Text Available The aim of this project is to communicate the basic laws of particle physics with Feynman diagrams - visual tools which represent elementary particle processes. They were originally developed as a code to be used by physicists and are still used today for calculations and elaborations of theoretical nature. The technical and mathematical rules of Feynman diagrams are obviously the exclusive concern of physicists, but on a pictorial level they can help to popularize many concepts, ranging from matter and the antimatter; the creation, destruction and transformation of particles; the role of ‘virtual’ particles in interactions; the conservation laws, symmetries, etc. Unlike the metaphors often used to describe the microcosm, these graphic representations provide an unequivocal translation of the physical content of the underlying quantum theory. As such they are perfect metaphors, not misleading constructions. A brief introduction on Feynman diagrams will be followed by the practical realization of this project, which will be carried out with the help of an experiment based on three-dimensional manipulable objects. The Feynman rules are expressed in terms of mechanical constraints on the possible conjuctions among the various elements of the experiment. The final part of the project will present the results of this experiment, which has been conducted among high-school students.

  1. Process and apparatus for recovery from rotating stall in axial flow fans and compressors

    OpenAIRE

    1997-01-01

    Active recovery from a rotating stall operating condition in an axial flow compression system is accomplished by altering the temperature and/or density of the working fluid flowing in the inlet of the compression system once rotating stall is detected. A burner is used to increase the compressor inlet flow temperature and concomitantly reduce the inlet flow density. Alternatively, a low density gas such as helium is injected into the compressor inlet. The ingestion of high temperature gases ...

  2. Design of Flow Systems for Improved Networking and Reduced Noise in Biomolecular Signal Processing in Biocomputing and Biosensing Applications.

    Science.gov (United States)

    Verma, Arjun; Fratto, Brian E; Privman, Vladimir; Katz, Evgeny

    2016-07-05

    We consider flow systems that have been utilized for small-scale biomolecular computing and digital signal processing in binary-operating biosensors. Signal measurement is optimized by designing a flow-reversal cuvette and analyzing the experimental data to theoretically extract the pulse shape, as well as reveal the level of noise it possesses. Noise reduction is then carried out numerically. We conclude that this can be accomplished physically via the addition of properly designed well-mixing flow-reversal cell(s) as an integral part of the flow system. This approach should enable improved networking capabilities and potentially not only digital but analog signal-processing in such systems. Possible applications in complex biocomputing networks and various sense-and-act systems are discussed.

  3. Design of Flow Systems for Improved Networking and Reduced Noise in Biomolecular Signal Processing in Biocomputing and Biosensing Applications

    Directory of Open Access Journals (Sweden)

    Arjun Verma

    2016-07-01

    Full Text Available We consider flow systems that have been utilized for small-scale biomolecular computing and digital signal processing in binary-operating biosensors. Signal measurement is optimized by designing a flow-reversal cuvette and analyzing the experimental data to theoretically extract the pulse shape, as well as reveal the level of noise it possesses. Noise reduction is then carried out numerically. We conclude that this can be accomplished physically via the addition of properly designed well-mixing flow-reversal cell(s as an integral part of the flow system. This approach should enable improved networking capabilities and potentially not only digital but analog signal-processing in such systems. Possible applications in complex biocomputing networks and various sense-and-act systems are discussed.

  4. Multicomponent statistical analysis to identify flow and transport processes in a highly-complex environment

    Science.gov (United States)

    Moeck, Christian; Radny, Dirk; Borer, Paul; Rothardt, Judith; Auckenthaler, Adrian; Berg, Michael; Schirmer, Mario

    2016-11-01

    A combined approach of multivariate statistical analysis, namely factor analysis (FA) and hierarchical cluster analysis (HCA), interpretation of geochemical processes, stable water isotope data and organic micropollutants enabling to assess spatial patterns of water types was performed for a study area in Switzerland, where drinking water production is close to different potential input pathways for contamination. To avoid drinking water contamination, artificial groundwater recharge with surface water into an aquifer is used to create a hydraulic barrier between potential intake pathways for contamination and drinking water extraction wells. Inter-aquifer mixing in the subsurface is identified, where a high amount of artificial infiltrated surface water is mixed with a lesser amount of water originating from the regional flow pathway in the vicinity of drinking water extraction wells. The spatial distribution of different water types can be estimated and a conceptual system understanding is developed. Results of the multivariate statistical analysis are comparable with gained information from isotopic data and organic micropollutants analyses. The integrated approach using different kinds of observations can be easily transferred to a variety of hydrological settings to synthesise and evaluate large hydrochemical datasets. The combination of additional data with different information content is conceivable and enabled effective interpretation of hydrological processes. Using the applied approach leads to more sound conceptual system understanding acting as the very basis to develop improved water resources management practices in a sustainable way.

  5. Formaldehyde degradation by UV/TiO2/O3 process using continuous flow mode

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The degradation of formaldehyde gas was studied using UV/TiO2/O3 process under the condition of continuous flow mode.The effects of humidity,initial formaldehyde concentration,residence time and ozone adding amount on degradation of formaldehyde gas were investigated.The experimental results indicated that the combination of ozonation with photocatalytic oxidation on the degradation of formaldehyde showed a synergetic action,e.g.,it could considerably increase decomposing of formaldehyde.The degradation efficiency of formaldehyde was between 73.6% and 79.4% while the initial concentration in the range of 1.84-24 mg/m3 by O3/TiO2/UV process.The optimal humidity was about 50% in UV/TiO2/O3 processs and degradation of formaldehyde increases from 39.0% to 94.1% when the ozone content increased from 0 to 141 mg/m3.Furthermore.the kinetics of formaldehyde degradation coefficient K of 0.0268 m3/mg were obtained.

  6. Formaldehyde degradation by UV/TiO2/O3 process using continuous flow mode.

    Science.gov (United States)

    Qi, Hong; Sun, De-Zhi; Chi, Guo-Qing

    2007-01-01

    The degradation of formaldehyde gas was studied using UV/TiO2/O3 process under the condition of continuous flow mode. The effects of humidity, initial formaldehyde concentration, residence time and ozone adding amount on degradation of formaldehyde gas were investigated. The experimental results indicated that the combination of ozonation with photocatalytic oxidation on the degradation of formaldehyde showed a synergetic action, e.g., it could considerably increase decomposing of formaldehyde. The degradation efficiency of formaldehyde was between 73.6% and 79.4% while the initial concentration in the range of 1.84-24 mg/m3 by O3/TiO2/UV process. The optimal humidity was about 50% in UV/TiO2/O3 processs and degradation of formaldehyde increases from 39.0% to 94.1% when the ozone content increased from 0 to 141 mg/m3. Furthermore, the kinetics of formaldehyde degradation reaction could be described by Langmuir-Hinshelwood model. The rate constant k of 46.72 mg/(m3 x min) and Langmuir adsorption coefficient K of 0.0268 m3/mg were obtained.

  7. Numerical Tools for Multicomponent, Multiphase, Reactive Processes: Flow of CO{sub 2} in Porous Medium

    Energy Technology Data Exchange (ETDEWEB)

    Khattri, Sanjay Kumar

    2006-07-01

    The thesis is concerned with numerically simulating multicomponent, multiphase, reactive transport in heterogeneous porous medium. Such processes are ubiquitous, for example, deposition of green house gases, flow of hydrocarbons and groundwater remediation. Understanding such processes is important from social and economic point of view. For the success of geological sequestration, an accurate estimation of migration patterns of green-house gases is essential. Due to an ever increasing computer power, computational mathematics has become an important tool for predicting dynamics of porous media fluids. Numerical and mathematical modelling of processes in a domain requires grid generation in the domain, discretization of the continuum equations on the generated grid, solution of the formed linear or nonlinear system of discrete equations and finally visualization of the results. The thesis is composed of three chapters and eight papers. Chapter 2 presents two techniques for generating structured quadrilateral and hexahedral meshes. These techniques are called algebraic and elliptic methods. Algebraic techniques are by far the most simple and computationally efficient method for grid generation. Transfinite interpolation operators are a kind of algebraic grid generation technique. In this chapter, many transfinite interpolation operators for grid generation are derived from 1D projection operators. In this chapter, some important properties of hexahedral elements are also mentioned. These properties are useful in discretization of partial differential equations on hexahedral mesh, improving quality of the hexahedral mesh, mesh generation and visualization. Chapter 3 is about CO{sub 2} flow in porous media. In this chapter, we present the mathematical models and their discretization for capturing major physical processes associated with CO{sub 2} deposition in geological formations. Some important simulations of practical applications in 2D and 3D are presented

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

    Directory of Open Access Journals (Sweden)

    A. Hernández-Antonio

    2015-02-01

    Full Text Available Groundwater chemistry and isotopic data from 40 production wells in the Atemajac and Toluquilla Valleys, located in and around the Guadalajara metropolitan area, were determined to develop a conceptual model of groundwater flow processes and mixing. Multivariate analysis including cluster analysis and principal component analysis were used to elucidate distribution patterns of constituents and factors controlling groundwater chemistry. Based on this analysis, groundwater was classified into four groups: cold groundwater, hydrothermal water, polluted groundwater and mixed groundwater. Cold groundwater is characterized by low temperature, salinity, and Cl and Na concentrations and is predominantly of Na-HCO3 type. It originates as recharge at Primavera caldera and is found predominantly in wells in the upper Atemajac Valley. Hydrothermal water is characterized by high salinity, temperature, Cl, Na, HCO3, and the presence of minor elements such as Li, Mn and F. It is a mixed HCO3 type found in wells from Toluquilla Valley and represents regional flow circulation through basaltic and andesitic rocks. Polluted groundwater is characterized by elevated nitrate and sulfate concentrations and is usually derived from urban water cycling and subordinately from agricultural practices. Mixed groundwaters between cold and hydrothermal components are predominantly found in the lower Atemajac Valley. Tritium method elucidated that practically all of the sampled groundwater contains at least a small fraction of modern water. The multivariate mixing model M3 indicates that the proportion of hydrothermal fluids in sampled well water is between 13 (local groundwater and 87% (hydrothermal water, and the proportion of polluted water in wells ranges from 0 to 63%. This study may help local water authorities to identify and quantify groundwater contamination and act accordingly.

  9. Analysis of a Methanol Decomposition Process by a Nonthermal Plasma Flow

    Science.gov (United States)

    Sato, Takehiko; Kambe, Makoto; Nishiyama, Hideya

    In the present study, experimental and numerical analyses were adopted to clarify key reactive species for methanol decomposition processes using a nonthermal plasma flow. The nonthermal plasma flow was generated by a dielectric barrier discharge (DBD) as a radical production source. The experimental methods were as follows. Working gas was air of 1-10Sl/min. The peak-to-peak applied voltage was 16-20kV with sine wave of 1Hz-7kHz. The characteristics of gas velocity, gas temperature, ozone concentration and methanol decomposition efficiency were measured. Those characteristics were also numerically analyzed using conservation equations of mass, chemical component, momentum and energy, and state of equation. The simulation model takes into account reactive species, which have chemical reaction with the methanol. The detailed reaction mechanism used in this model consists of 108 elementary reactions and 41 chemical species. Inlet conditions are partially given by experimental results. Finally, effects of reactive species such as O, OH, H, NO, etc. on methanol decomposition characteristics are numerically analyzed. The results obtained in this study are summarized as follows. (1) Existence of excited atoms of O, N and excited molecular of OH, N2(B3Πg), N2(A3Σu+), NO are implied in the discharge region. (2) The methanol below 50ppm is decomposed completely by using DBD at discharge conditions as V=16kVpp and f=100Hz. (3) The reactive species are most important factor to decompose methanol, as the full decomposition is obtained under all injection positions. (4) In numerical analysis, it is clarified that OH is the important radical to decompose the methanol.

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

    DEFF Research Database (Denmark)

    Bauer-Gottwein, Peter; Langer, T.; Prommer, H.;

    2006-01-01

    This paper analyses the interactions of density driven flow and geochemical reactions under evapo-concentration. A multi-species hydrodynamic flow and transport simulation model (SEAWAT) is coupled to a batch reaction model (PHREEQC) to analyze densitydriven flow on islands in the Okavango Delta......, Botswana. Evapo-concentration on the islands leads to steadily increasing concentrations until the onset of density-driven flow against the evaporation-induced upward gradient. Lag times to the onset of density-driven flow are strongly influenced by geochemical reactions. Mineral precipitation and carbon...

  11. Articulated Entity Relationship (AER Diagram for Complete Automation of Relational Database Normalization

    Directory of Open Access Journals (Sweden)

    P. S. Dhabe

    2010-05-01

    Full Text Available In this paper an Articulated Entity Relationship (AER diagram is proposed, which is an extension of EntityRelationship (ER diagram to accommodate the Functional Dependency (FD information as its integral partfor complete automation of normalization. In current relational databases (RDBMS automation ofnormalization by top down approach is possible using ER diagram as an input, provided the FD informationis available independently, meanwhile, through user interaction. Such automation we call partial andconditional automation. To avoid this user interaction, there is a strong need to accommodate FDinformation as an element of ER diagram itself. Moreover, ER diagrams are not designed by taking intoaccount the requirements of normalization. However, for better automation of normalization it must be anintegral part of conceptual design (ER Diagram. The prime motivation behind this paper to design a systemthat need only proposed AER diagram as a sole input and normalize the database up to a given normal formin one go. This would allow more amount of automation than the current approach. Such automation we callas total and unconditional automation, which is better and complete in true sense. As the proposed AERdiagram is designed by taking in to account the normalization process, normalization up to Boyce CoddNormal Form (BCNF becomes an integral part of conceptual design. Additional advantage of AER diagramis that any modifications (addition, deletion or updation of attributes made to the AER diagram willautomatically be reflected in its FD information. Thus description of schema and FD information isguaranteed to be consistent. This cannot be assured in current approach using ER diagrams, as schema andFD information are provided to the system at two different times, separately.

  12. Investigating redox processes under diffusive and advective flow conditions using a coupled omics and synchrotron approach

    Science.gov (United States)

    Kemner, K. M.; Boyanov, M.; Flynn, T. M.; O'Loughlin, E. J.; Antonopoulos, D. A.; Kelly, S.; Skinner, K.; Mishra, B.; Brooks, S. C.; Watson, D. B.; Wu, W. M.

    2015-12-01

    FeIII- and SO42--reducing microorganisms and the mineral phases they produce have profound implications for many processes in aquatic and terrestrial systems. In addition, many of these microbially-catalysed geochemical transformations are highly dependent upon introduction of reactants via advective and diffusive hydrological transport. We have characterized microbial communities from a set of static microcosms to test the effect of ethanol diffusion and sulfate concentration on UVI-contaminated sediment. The spatial distribution, valence states, and speciation of both U and Fe were monitored in situ throughout the experiment by synchrotron x-ray absorption spectroscopy, in parallel with solution measurements of pH and the concentrations of sulfate, ethanol, and organic acids. After reaction initiation, a ~1-cm thick layer of sediment near the sediment-water (S-W) interface became visibly dark. Fe XANES spectra of the layer were consistent with the formation of FeS. Over the 4 year duration of the experiment, U LIII-edge XANES indicated reduction of U, first in the dark layer and then throughout the sediment. Next, the microcosms were disassembled and samples were taken from the overlying water and different sediment regions. We extracted DNA and characterized the microbial community by sequencing 16S rRNA gene amplicons with the Illumina MiSeq platform and found that the community evolved from its originally homogeneous composition, becoming significantly spatially heterogeneous. We have also developed an x-ray accessible column to probe elemental transformations as they occur along the flow path in a porous medium with the purpose of refining reactive transport models (RTMs) that describe coupled physical and biogeochemical processes in environmental systems. The elemental distribution dynamics and the RTMs of the redox driven processes within them will be presented.

  13. Phase Diagram of Vertically Shaken Granular Matter

    CERN Document Server

    Eshuis, P; Lohse, D; Van der Meer, D; Van der Weele, K; Bos, Robert; Eshuis, Peter; Lohse, Detlef; Meer, Devaraj van der; Weele, Ko van der

    2006-01-01

    A shallow, vertically shaken granular bed in a quasi 2-D container is studied experimentally yielding a wider variety of phenomena than in any previous study: (1) bouncing bed, (2) undulations, (3) granular Leidenfrost effect, (4) convection rolls, and (5) granular gas. These phenomena and the transitions between them are characterized by dimensionless control parameters and combined in a full experimental phase diagram.

  14. Visualizing Multivariate Attributes on Software Diagrams

    NARCIS (Netherlands)

    Byelas, Heorhiy; Telea, Alexandru; Winter, A; Knodel, J

    2009-01-01

    Software architecture diagrams and metrics are well-known and heavily used in many areas in software engineering. However they are rarely combined in one (visual) representation. Although there are some advances in this direction, there are also some limitations. In this research, we study how to ov

  15. Orphan-Free Anisotropic Voronoi Diagrams

    CERN Document Server

    Canas, Guillermo D

    2011-01-01

    We describe conditions under which an appropriately-defined anisotropic Voronoi diagram of a set of sites in Euclidean space is guaranteed to be composed of connected cells in any number of dimensions. These conditions are natural for problems in optimization and approximation, and algorithms already exist to produce sets of sites that satisfy them.

  16. Modeling the phase diagram of carbon

    NARCIS (Netherlands)

    Ghiringhelli, L.M.; Los, J.H.; Meijer, E.J.; Fasolino, A.; Frenkel, D.

    2005-01-01

    We determined the phase diagram involving diamond, graphite, and liquid carbon using a recently developed semiempirical potential. Using accurate free-energy calculations, we computed the solid-solid and solid-liquid phase boundaries for pressures and temperatures up to 400 GPa and 12 000 K, respect

  17. Diagram of a LEP superconducting cavity

    CERN Multimedia

    1991-01-01

    This diagram gives a schematic representation of the superconducting radio-frequency cavities at LEP. Liquid helium is used to cool the cavity to 4.5 degrees above absolute zero so that very high electric fields can be produced, increasing the operating energy of the accelerator. Superconducting cavities were used only in the LEP-2 phase of the accelerator, from 1996 to 2000.

  18. Phase Diagrams of Strongly Interacting Theories

    DEFF Research Database (Denmark)

    Sannino, Francesco

    2010-01-01

    We summarize the phase diagrams of SU, SO and Sp gauge theories as function of the number of flavors, colors, and matter representation as well as the ones of phenomenologically relevant chiral gauge theories such as the Bars-Yankielowicz and the generalized Georgi-Glashow models. We finally repo...

  19. Influence Diagrams for Optimal Maintenance Planning

    DEFF Research Database (Denmark)

    Friis-Hansen, Andreas

    2000-01-01

    Over the last two decades Bayesian networks and influence diagrams have received notable attention within the field of artificial intelligence and expert systems. During the last few years the technology has been further developed for problem solving within other engineering fields. The objective...

  20. Geometrical splitting and reduction of Feynman diagrams

    Science.gov (United States)

    Davydychev, Andrei I.

    2016-10-01

    A geometrical approach to the calculation of N-point Feynman diagrams is reviewed. It is shown that the geometrical splitting yields useful connections between Feynman integrals with different momenta and masses. It is demonstrated how these results can be used to reduce the number of variables in the occurring functions.