Sample records for commercial software fluent

  1. CFD RANS Simulations on a Generic Conventional Scale Model Submarine: Comparison between Fluent and OpenFOAM

    DTIC Science & Technology

    2015-09-01

    lift and drag forces on two model car geometries (designated as the VRAK model and the S80 model). For the VRAK model the OpenFOAM drag coefficient was...lift coefficient was 16.5% higher than the Fluent value. Both model car geometries were meshed using Harpoon, which is a commercial software package...2. Clarke, G., Vun, S., Giacobello, M. and Reddy, R., “Estimation of ARH Tiger Fuselage Aerodynamic Characteristics Using Computational Fluid

  2. Development and testing of a numerical simulation method for thermally nonequilibrium dissociating flows in ANSYS Fluent

    NASA Astrophysics Data System (ADS)

    Shoev, G. V.; Bondar, Ye. A.; Oblapenko, G. P.; Kustova, E. V.

    2016-03-01

    Various issues of numerical simulation of supersonic gas flows with allowance for thermochemical nonequilibrium on the basis of fluid dynamic equations in the two-temperature approximation are discussed. The computational tool for modeling flows with thermochemical nonequilibrium is the commercial software package ANSYS Fluent with an additional userdefined open-code module. A comparative analysis of results obtained by various models of vibration-dissociation coupling in binary gas mixtures of nitrogen and oxygen is performed. Results of numerical simulations are compared with available experimental data.

  3. CFD Modeling of Water Flow through Sudden Contraction and Expansion in a Horizontal Pipe

    ERIC Educational Resources Information Center

    Kaushik, V. V. R.; Ghosh, S.; Das, G.; Das, P. K.

    2011-01-01

    This paper deals with the use of commercial CFD software in teaching graduate level computational fluid dynamics. FLUENT 6.3.26 was chosen as the CFD software to teach students the entire CFD process in a single course. The course objective is to help students to learn CFD, use it in some practical problems and analyze as well as validate the…

  4. Performance Assessment of the Commercial CFD Software for the Prediction of the Reactor Internal Flow

    NASA Astrophysics Data System (ADS)

    Lee, Gong Hee; Bang, Young Seok; Woo, Sweng Woong; Kim, Do Hyeong; Kang, Min Ku

    2014-06-01

    As the computer hardware technology develops the license applicants for nuclear power plant use the commercial CFD software with the aim of reducing the excessive conservatism associated with using simplified and conservative analysis tools. Even if some of CFD software developer and its user think that a state of the art CFD software can be used to solve reasonably at least the single-phase nuclear reactor problems, there is still limitation and uncertainty in the calculation result. From a regulatory perspective, Korea Institute of Nuclear Safety (KINS) is presently conducting the performance assessment of the commercial CFD software for nuclear reactor problems. In this study, in order to examine the validity of the results of 1/5 scaled APR+ (Advanced Power Reactor Plus) flow distribution tests and the applicability of CFD in the analysis of reactor internal flow, the simulation was conducted with the two commercial CFD software (ANSYS CFX V.14 and FLUENT V.14) among the numerous commercial CFD software and was compared with the measurement. In addition, what needs to be improved in CFD for the accurate simulation of reactor core inlet flow was discussed.

  5. CFD modeling of space-time evolution of fast pyrolysis products in a bench-scale fluidized-bed reactor

    USDA-ARS?s Scientific Manuscript database

    A model for the evolution of pyrolysis products in a fluidized bed has been developed. In this study the unsteady constitutive transport equations for inert gas flow and decomposition kinetics were modeled using the commercial computational fluid dynamics (CFD) software FLUENT-12. The model system d...

  6. Numerical modeling tools for chemical vapor deposition

    NASA Technical Reports Server (NTRS)

    Jasinski, Thomas J.; Childs, Edward P.

    1992-01-01

    Development of general numerical simulation tools for chemical vapor deposition (CVD) was the objective of this study. Physical models of important CVD phenomena were developed and implemented into the commercial computational fluid dynamics software FLUENT. The resulting software can address general geometries as well as the most important phenomena occurring with CVD reactors: fluid flow patterns, temperature and chemical species distribution, gas phase and surface deposition. The physical models are documented which are available and examples are provided of CVD simulation capabilities.

  7. Software and Systems Test Track Architecture and Concept Definition

    DTIC Science & Technology

    2007-05-01

    Light 11.0 11.0 11.0 ASC Flex Free Software Foundation 2.5.31 2.5.31 2.5.31 ASC Fluent Fluent Inc. 6.2.26 6.2.26 6.2.26 6.2.26 ASC FMD ...11 ERDC Fluent Fluent 6.2.16 ERDC Fortran 77/90 compiler Compaq/Cray/SGI 7.4 7.4.3m 7.4.4m 5.6 ERDC FTA Platform 1.1 1.1 1.1 ERDC GAMESS

  8. Comparison of particle tracking algorithms in commercial CFD packages: sedimentation and diffusion.

    PubMed

    Robinson, Risa J; Snyder, Pam; Oldham, Michael J

    2007-05-01

    Computational fluid dynamic modeling software has enabled microdosimetry patterns of inhaled toxins and toxicants to be predicted and visualized, and is being used in inhalation toxicology and risk assessment. These predicted microdosimetry patterns in airway structures are derived from predicted airflow patterns within these airways and particle tracking algorithms used in computational fluid dynamics (CFD) software packages. Although these commercial CFD codes have been tested for accuracy under various conditions, they have not been well tested for respiratory flows in general. Nor has their particle tracking algorithm accuracy been well studied. In this study, three software packages, Fluent Discrete Phase Model (DPM), Fluent Fine Particle Model (FPM), and ANSYS CFX, were evaluated. Sedimentation and diffusion were each isolated in a straight tube geometry and tested for accuracy. A range of flow rates corresponding to adult low activity (minute ventilation = 10 L/min) and to heavy exertion (minute ventilation = 60 L/min) were tested by varying the range of dimensionless diffusion and sedimentation parameters found using the Weibel symmetric 23 generation lung morphology. Numerical results for fully developed parabolic and uniform (slip) profiles were compared respectively, to Pich (1972) and Yu (1977) analytical sedimentation solutions. Schum and Yeh (1980) equations for sedimentation were also compared. Numerical results for diffusional deposition were compared to analytical solutions of Ingham (1975) for parabolic and uniform profiles. Significant differences were found among the various CFD software packages and between numerical and analytical solutions. Therefore, it is prudent to validate CFD predictions against analytical solutions in idealized geometry before tackling the complex geometries of the respiratory tract.

  9. Applications of CFD and visualization techniques

    NASA Technical Reports Server (NTRS)

    Saunders, James H.; Brown, Susan T.; Crisafulli, Jeffrey J.; Southern, Leslie A.

    1992-01-01

    In this paper, three applications are presented to illustrate current techniques for flow calculation and visualization. The first two applications use a commercial computational fluid dynamics (CFD) code, FLUENT, performed on a Cray Y-MP. The results are animated with the aid of data visualization software, apE. The third application simulates a particulate deposition pattern using techniques inspired by developments in nonlinear dynamical systems. These computations were performed on personal computers.

  10. Numerical simulation of nonequilibrium flows by using the state-to-state approach in commercial software

    NASA Astrophysics Data System (ADS)

    Kunova, O. V.; Shoev, G. V.; Kudryavtsev, A. N.

    2017-01-01

    Nonequilibrium flows of a two-component oxygen mixture O2/O behind a shock wave are studied with due allowance for the state-to-state vibrational and chemical kinetics. The system of gas-dynamic equations is supplemented with kinetic equations including contributions of VT (TV)-exchange and dissociation processes. A method of the numerical solution of this system with the use of the ANSYS Fluent commercial software package is proposed, which is used in a combination with the authors' code that takes into account nonequilibrium kinetics. The computed results are compared with parameters obtained by solving the problem in the shock-fitting formulation. The vibrational temperature is compared with experimental data. The numerical tool proposed in the present paper is applied to study the flow around a cylinder.

  11. Numerical modeling of immiscible two-phase flow in micro-models using a commercial CFD code

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Crandall, Dustin; Ahmadia, Goodarz; Smith, Duane H.

    2009-01-01

    Off-the-shelf CFD software is being used to analyze everything from flow over airplanes to lab-on-a-chip designs. So, how accurately can two-phase immiscible flow be modeled flowing through some small-scale models of porous media? We evaluate the capability of the CFD code FLUENT{trademark} to model immiscible flow in micro-scale, bench-top stereolithography models. By comparing the flow results to experimental models we show that accurate 3D modeling is possible.

  12. Computational Analysis of Human Blood Flow

    NASA Astrophysics Data System (ADS)

    Panta, Yogendra; Marie, Hazel; Harvey, Mark

    2009-11-01

    Fluid flow modeling with commercially available computational fluid dynamics (CFD) software is widely used to visualize and predict physical phenomena related to various biological systems. In this presentation, a typical human aorta model was analyzed assuming the blood flow as laminar with complaint cardiac muscle wall boundaries. FLUENT, a commercially available finite volume software, coupled with Solidworks, a modeling software, was employed for the preprocessing, simulation and postprocessing of all the models.The analysis mainly consists of a fluid-dynamics analysis including a calculation of the velocity field and pressure distribution in the blood and a mechanical analysis of the deformation of the tissue and artery in terms of wall shear stress. A number of other models e.g. T branches, angle shaped were previously analyzed and compared their results for consistency for similar boundary conditions. The velocities, pressures and wall shear stress distributions achieved in all models were as expected given the similar boundary conditions. The three dimensional time dependent analysis of blood flow accounting the effect of body forces with a complaint boundary was also performed.

  13. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pauzi, Anas Muhamad, E-mail: Anas@uniten.edu.my; Cioncolini, Andrea; Iacovides, Hector

    The Molten Salt Reactor (MSR) is one of the most promising system proposed by Generation IV Forum (GIF) for future nuclear reactor systems. Advantages of the MSR are significantly larger compared to other reactor system, and is mainly achieved from its liquid nature of fuel and coolant. Further improvement to this system, which is a natural circulating molten fuel salt inside its tube in the reactor core is proposed, to achieve advantages of reducing and simplifying the MSR design proposed by GIF. Thermal hydraulic analysis on the proposed system was completed using a commercial computation fluid dynamics (CFD) software calledmore » FLUENT by ANSYS Inc. An understanding on theory behind this unique natural circulation flow inside the tube caused by fission heat generated in molten fuel salt and tube cooling was briefly introduced. Currently, no commercial CFD software could perfectly simulate natural circulation flow, hence, modeling this flow problem in FLUENT is introduced and analyzed to obtain best simulation results. Results obtained demonstrate the existence of periodical transient nature of flow problem, hence improvements in tube design is proposed based on the analysis on temperature and velocity profile. Results show that the proposed system could operate at up to 750MW core power, given that turbulence are enhanced throughout flow region, and precise molten fuel salt physical properties could be defined. At the request of the authors and the Proceedings Editor the name of the co-author Andrea Cioncolini was corrected from Andrea Coincolini. The same name correction was made in the Acknowledgement section on page 030004-10 and in reference number 4. The updated article was published on 11 May 2015.« less

  14. Stirling Analysis Comparison of Commercial vs. High-Order Methods

    NASA Technical Reports Server (NTRS)

    Dyson, Rodger W.; Wilson, Scott D.; Tew, Roy C.; Demko, Rikako

    2007-01-01

    Recently, three-dimensional Stirling engine simulations have been accomplished utilizing commercial Computational Fluid Dynamics software. The validations reported can be somewhat inconclusive due to the lack of precise time accurate experimental results from engines, export control/ proprietary concerns, and the lack of variation in the methods utilized. The last issue may be addressed by solving the same flow problem with alternate methods. In this work, a comprehensive examination of the methods utilized in the commercial codes is compared with more recently developed high-order methods. Specifically, Lele's Compact scheme and Dyson s Ultra Hi-Fi method will be compared with the SIMPLE and PISO methods currently employed in CFD-ACE, FLUENT, CFX, and STAR-CD (all commercial codes which can in theory solve a three-dimensional Stirling model although sliding interfaces and their moving grids limit the effective time accuracy). We will initially look at one-dimensional flows since the current standard practice is to design and optimize Stirling engines with empirically corrected friction and heat transfer coefficients in an overall one-dimensional model. This comparison provides an idea of the range in which commercial CFD software for modeling Stirling engines may be expected to provide accurate results. In addition, this work provides a framework for improving current one-dimensional analysis codes.

  15. Stirling Analysis Comparison of Commercial Versus High-Order Methods

    NASA Technical Reports Server (NTRS)

    Dyson, Rodger W.; Wilson, Scott D.; Tew, Roy C.; Demko, Rikako

    2005-01-01

    Recently, three-dimensional Stirling engine simulations have been accomplished utilizing commercial Computational Fluid Dynamics software. The validations reported can be somewhat inconclusive due to the lack of precise time accurate experimental results from engines, export control/proprietary concerns, and the lack of variation in the methods utilized. The last issue may be addressed by solving the same flow problem with alternate methods. In this work, a comprehensive examination of the methods utilized in the commercial codes is compared with more recently developed high-order methods. Specifically, Lele's compact scheme and Dyson's Ultra Hi-Fi method will be compared with the SIMPLE and PISO methods currently employed in CFD-ACE, FLUENT, CFX, and STAR-CD (all commercial codes which can in theory solve a three-dimensional Stirling model with sliding interfaces and their moving grids limit the effective time accuracy). We will initially look at one-dimensional flows since the current standard practice is to design and optimize Stirling engines with empirically corrected friction and heat transfer coefficients in an overall one-dimensional model. This comparison provides an idea of the range in which commercial CFD software for modeling Stirling engines may be expected to provide accurate results. In addition, this work provides a framework for improving current one-dimensional analysis codes.

  16. CFD Modeling of Flow, Temperature, and Concentration Fields in a Pilot-Scale Rotary Hearth Furnace

    NASA Astrophysics Data System (ADS)

    Liu, Ying; Su, Fu-Yong; Wen, Zhi; Li, Zhi; Yong, Hai-Quan; Feng, Xiao-Hong

    2014-01-01

    A three-dimensional mathematical model for simulation of flow, temperature, and concentration fields in a pilot-scale rotary hearth furnace (RHF) has been developed using a commercial computational fluid dynamics software, FLUENT. The layer of composite pellets under the hearth is assumed to be a porous media layer with CO source and energy sink calculated by an independent mathematical model. User-defined functions are developed and linked to FLUENT to process the reduction process of the layer of composite pellets. The standard k-ɛ turbulence model in combination with standard wall functions is used for modeling of gas flow. Turbulence-chemistry interaction is taken into account through the eddy-dissipation model. The discrete ordinates model is used for modeling of radiative heat transfer. A comparison is made between the predictions of the present model and the data from a test of the pilot-scale RHF, and a reasonable agreement is found. Finally, flow field, temperature, and CO concentration fields in the furnace are investigated by the model.

  17. Design of an ammonia closed-loop storage system in a CSP power plant with a power tower cavity receiver

    NASA Astrophysics Data System (ADS)

    Abdiwe, Ramadan; Haider, Markus

    2017-06-01

    In this study the thermochemical system using ammonia as energy storage carrier is investigated and a transient mathematical model using MATLAB software was developed to predict the behavior of the ammonia closed-loop storage system including but not limited to the ammonia solar reactor and the ammonia synthesis reactor. The MATLAB model contains transient mass and energy balances as well as chemical equilibrium model for each relevant system component. For the importance of the dissociation and formation processes in the system, a Computational Fluid Dynamics (CFD) simulation on the ammonia solar and synthesis reactors has been performed. The CFD commercial package FLUENT is used for the simulation study and all the important mechanisms for packed bed reactors are taken into account, such as momentum, heat and mass transfer, and chemical reactions. The FLUENT simulation reveals the profiles inside both reactors and compared them with the profiles from the MATLAB code.

  18. CFD simulation and experimental validation of a GM type double inlet pulse tube refrigerator

    NASA Astrophysics Data System (ADS)

    Banjare, Y. P.; Sahoo, R. K.; Sarangi, S. K.

    2010-04-01

    Pulse tube refrigerator has the advantages of long life and low vibration over the conventional cryocoolers, such as GM and stirling coolers because of the absence of moving parts in low temperature. This paper performs a three-dimensional computational fluid dynamic (CFD) simulation of a GM type double inlet pulse tube refrigerator (DIPTR) vertically aligned, operating under a variety of thermal boundary conditions. A commercial computational fluid dynamics (CFD) software package, Fluent 6.1 is used to model the oscillating flow inside a pulse tube refrigerator. The simulation represents fully coupled systems operating in steady-periodic mode. The externally imposed boundary conditions are sinusoidal pressure inlet by user defined function at one end of the tube and constant temperature or heat flux boundaries at the external walls of the cold-end heat exchangers. The experimental method to evaluate the optimum parameters of DIPTR is difficult. On the other hand, developing a computer code for CFD analysis is equally complex. The objectives of the present investigations are to ascertain the suitability of CFD based commercial package, Fluent for study of energy and fluid flow in DIPTR and to validate the CFD simulation results with available experimental data. The general results, such as the cool down behaviours of the system, phase relation between mass flow rate and pressure at cold end, the temperature profile along the wall of the cooler and refrigeration load are presented for different boundary conditions of the system. The results confirm that CFD based Fluent simulations are capable of elucidating complex periodic processes in DIPTR. The results also show that there is an excellent agreement between CFD simulation results and experimental results.

  19. Parametric study of natural circulation flow in molten salt fuel in molten salt reactor

    NASA Astrophysics Data System (ADS)

    Pauzi, Anas Muhamad; Cioncolini, Andrea; Iacovides, Hector

    2015-04-01

    The Molten Salt Reactor (MSR) is one of the most promising system proposed by Generation IV Forum (GIF) for future nuclear reactor systems. Advantages of the MSR are significantly larger compared to other reactor system, and is mainly achieved from its liquid nature of fuel and coolant. Further improvement to this system, which is a natural circulating molten fuel salt inside its tube in the reactor core is proposed, to achieve advantages of reducing and simplifying the MSR design proposed by GIF. Thermal hydraulic analysis on the proposed system was completed using a commercial computation fluid dynamics (CFD) software called FLUENT by ANSYS Inc. An understanding on theory behind this unique natural circulation flow inside the tube caused by fission heat generated in molten fuel salt and tube cooling was briefly introduced. Currently, no commercial CFD software could perfectly simulate natural circulation flow, hence, modeling this flow problem in FLUENT is introduced and analyzed to obtain best simulation results. Results obtained demonstrate the existence of periodical transient nature of flow problem, hence improvements in tube design is proposed based on the analysis on temperature and velocity profile. Results show that the proposed system could operate at up to 750MW core power, given that turbulence are enhanced throughout flow region, and precise molten fuel salt physical properties could be defined. At the request of the authors and the Proceedings Editor the name of the co-author Andrea Cioncolini was corrected from Andrea Coincolini. The same name correction was made in the Acknowledgement section on page 030004-10 and in reference number 4. The updated article was published on 11 May 2015.

  20. Wind conditions in urban layout - Numerical and experimental research

    NASA Astrophysics Data System (ADS)

    Poćwierz, Marta; Zielonko-Jung, Katarzyna

    2018-01-01

    This paper presents research which compares the numerical and the experimental results for different cases of airflow around a few urban layouts. The study is concerned mostly with the analysis of parameters, such as pressure and velocity fields, which are essential in the building industry. Numerical simulations have been performed by the commercial software Fluent, with the use of a few different turbulence models, including popular k-ɛ, k-ɛ realizable or k-ω. A particular attention has been paid to accurate description of the conditions on the inlet and the selection of suitable computing grid. The pressure measurement near buildings and oil visualization were undertaken and described accordingly.

  1. Numerical wind-tunnel simulation for Spar platform

    NASA Astrophysics Data System (ADS)

    Shen, Wenjun

    2017-05-01

    ANSYS Fluent software is used in the simulation analysis of numerical wind tunnel model for the upper Spar platform module. Design Modeler (DM), Meshing, FLUENT and CFD-POST are chosen in the numerical calculation. And DM is used to deal with and repair the geometric model, and Meshing is used to mesh the model, Fluent is used to set up and solve the calculation condition, finally CFD-POST is used for post-processing of the results. The wind loads are obtained under different direction and incidence angles. Finally, comparison is made between numerical results and empirical formula.

  2. Numerical evaluation of an innovative cup layout for open volumetric solar air receivers

    NASA Astrophysics Data System (ADS)

    Cagnoli, Mattia; Savoldi, Laura; Zanino, Roberto; Zaversky, Fritz

    2016-05-01

    This paper proposes an innovative volumetric solar absorber design to be used in high-temperature air receivers of solar power tower plants. The innovative absorber, a so-called CPC-stacked-plate configuration, applies the well-known principle of a compound parabolic concentrator (CPC) for the first time in a volumetric solar receiver, heating air to high temperatures. The proposed absorber configuration is analyzed numerically, applying first the open-source ray-tracing software Tonatiuh in order to obtain the solar flux distribution on the absorber's surfaces. Next, a Computational Fluid Dynamic (CFD) analysis of a representative single channel of the innovative receiver is performed, using the commercial CFD software ANSYS Fluent. The solution of the conjugate heat transfer problem shows that the behavior of the new absorber concept is promising, however further optimization of the geometry will be necessary in order to exceed the performance of the classical absorber designs.

  3. Membrane-based actuation for high-speed single molecule force spectroscopy studies using AFM.

    PubMed

    Sarangapani, Krishna; Torun, Hamdi; Finkler, Ofer; Zhu, Cheng; Degertekin, Levent

    2010-07-01

    Atomic force microscopy (AFM)-based dynamic force spectroscopy of single molecular interactions involves characterizing unbinding/unfolding force distributions over a range of pulling speeds. Owing to their size and stiffness, AFM cantilevers are adversely affected by hydrodynamic forces, especially at pulling speeds >10 microm/s, when the viscous drag becomes comparable to the unbinding/unfolding forces. To circumvent these adverse effects, we have fabricated polymer-based membranes capable of actuating commercial AFM cantilevers at speeds >or=100 microm/s with minimal viscous drag effects. We have used FLUENT, a computational fluid dynamics (CFD) software, to simulate high-speed pulling and fast actuation of AFM cantilevers and membranes in different experimental configurations. The simulation results support the experimental findings on a variety of commercial AFM cantilevers and predict significant reduction in drag forces when membrane actuators are used. Unbinding force experiments involving human antibodies using these membranes demonstrate that it is possible to achieve bond loading rates >or=10(6) pN/s, an order of magnitude greater than that reported with commercial AFM cantilevers and systems.

  4. The effect of balance holes to centrifugal pump performance

    NASA Astrophysics Data System (ADS)

    Babayigit, O.; Ozgoren, M.; Aksoy, M. H.; Kocaaslan, O.

    2017-07-01

    The aim of this study is to analyze of a centrifugal pump with and without balance holes by using ANSYS-Fluent software. The pump used in the study is a commercial centrifugal pump consisting of two stages that is a model of Sempa Pump Company. Firstly, models of impeller, diffuser, suction and discharge sections of the centrifugal pump were separately drawn using Ansys and Solidworks software. Later, grid structures were generated on the flow volume of the pump. Turbulent flow volume was numerically solved by realizable k-є turbulence model. The flow analyses were focused on the centrifugal pump performance and the flow characteristics under different operational conditions with/without balance holes. Distributions of flow characteristics such as velocity and pressure distributions in the flow volume were also determined, numerically. The results of Computational Fluid Dynamics (CFD) with/without balance holes for the pump head and hydraulic efficiency on the design flow rate of 80 m3/h were found to be 81.5/91.3 m and 51.9/65.3%, respectively.

  5. Modeling of an argon cascaded arc plasma by ANSYS FLUENT

    NASA Astrophysics Data System (ADS)

    Wei, Guodong; Qi, Xin; Yang, Lei

    2014-04-01

    In this work, an argon cascaded arc plasma is simulated by the business software ANSYS FLUENT. In fact, thus plasma is a high temperature arc (plasma window) with an average temperature of 12000 °C, which can be used as a medium between high pressure and vacuum mainly due to its characteristics of high temperature. According to the simulating results, the temperature can reach as high as 11500 °C which is in great agreement with that of other reports about plasma window.

  6. Numerical investigation of rarefaction effects in the vicinity of a sharp leading edge

    NASA Astrophysics Data System (ADS)

    Pan, Shaowu; Gao, Zhenxun; Lee, Chunhian

    2014-12-01

    This paper presents a study of rarefaction effect on hypersonic flow over a sharp leading edge. Both continuum approach and kinetic method: a widely spread commercial Computational Fluid Dynamics-Navior-Stokes-Fourier (CFD-NSF) software - Fluent together with a direct simulation Monte Carlo (DSMC) code developed by the authors are employed for simulation of transition regime with Knudsen number ranging from 0.005 to 0.2. It is found that Fluent can predict the wall fluxes in the case of hypersonic argon flow over the sharp leading edge for the lowest Kn case (Kn = 0.005) in current paper while for other cases it also has a good agreement with DSMC except at the location near the sharp leading edge. Among all of the wall fluxes, it is found that coefficient of pressure is the most sensitive to rarefaction while heat transfer is the least one. A parameter based on translational nonequilibrium and a cut-off value of 0.34 is proposed for continuum breakdown in this paper. The structure of entropy and velocity profile in boundary layer is analyzed. Also, it is found that the ratio of heat transfer coefficient to skin friction coefficient remains uniform along the surface for the four cases in this paper.

  7. The numerical modelling of mixing phenomena of nanofluids in passive micromixers

    NASA Astrophysics Data System (ADS)

    Milotin, R.; Lelea, D.

    2018-01-01

    The paper deals with the rapid mixing phenomena in micro-mixing devices with four tangential injections and converging tube, considering nanoparticles and water as the base fluid. Several parameters like Reynolds number (Re = 6 - 284) or fluid temperature are considered in order to optimize the process and obtain fundamental insight in mixing phenomena. The set of partial differential equations is considered based on conservation of momentum and species. Commercial package software Ansys-Fluent is used for solution of differential equations, based on a finite volume method. The results reveal that mixing index and mixing process is strongly dependent both on Reynolds number and heat flux. Moreover there is a certain Reynolds number when flow instabilities are generated that intensify the mixing process due to the tangential injections of the fluids.

  8. System Engineering Approach to Assessing Integrated Survivability

    DTIC Science & Technology

    2009-08-01

    based response for the above engagements using LS- Dyna for blast modelling, MADYMO for safety and human response, CFD software (Fluent) is used to...Simulation JFAS Joint Force Analysis Simulation JANUS Joint Army Navy Uniform Simulation LS- DYNA Livermore Software-Dynamics MADYMO...management technologies. The “don’t be killed” layer of survivability protection accounts for many of the mitigation technologies (i.e. blast

  9. Computational Fluid Dynamic simulations of pipe elbow flow.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Homicz, Gregory Francis

    2004-08-01

    One problem facing today's nuclear power industry is flow-accelerated corrosion and erosion in pipe elbows. The Korean Atomic Energy Research Institute (KAERI) is performing experiments in their Flow-Accelerated Corrosion (FAC) test loop to better characterize these phenomena, and develop advanced sensor technologies for the condition monitoring of critical elbows on a continuous basis. In parallel with these experiments, Sandia National Laboratories is performing Computational Fluid Dynamic (CFD) simulations of the flow in one elbow of the FAC test loop. The simulations are being performed using the FLUENT commercial software developed and marketed by Fluent, Inc. The model geometry and meshmore » were created using the GAMBIT software, also from Fluent, Inc. This report documents the results of the simulations that have been made to date; baseline results employing the RNG k-e turbulence model are presented. The predicted value for the diametrical pressure coefficient is in reasonably good agreement with published correlations. Plots of the velocities, pressure field, wall shear stress, and turbulent kinetic energy adjacent to the wall are shown within the elbow section. Somewhat to our surprise, these indicate that the maximum values of both wall shear stress and turbulent kinetic energy occur near the elbow entrance, on the inner radius of the bend. Additional simulations were performed for the same conditions, but with the RNG k-e model replaced by either the standard k-{var_epsilon}, or the realizable k-{var_epsilon} turbulence model. The predictions using the standard k-{var_epsilon} model are quite similar to those obtained in the baseline simulation. However, with the realizable k-{var_epsilon} model, more significant differences are evident. The maximums in both wall shear stress and turbulent kinetic energy now appear on the outer radius, near the elbow exit, and are {approx}11% and 14% greater, respectively, than those predicted in the baseline calculation; secondary maxima in both quantities still occur near the elbow entrance on the inner radius. Which set of results better reflects reality must await experimental corroboration. Additional calculations demonstrate that whether or not FLUENT's radial equilibrium pressure distribution option is used in the PRESSURE OUTLET boundary condition has no significant impact on the flowfield near the elbow. Simulations performed with and without the chemical sensor and associated support bracket that were present in the experiments demonstrate that the latter have a negligible influence on the flow in the vicinity of the elbow. The fact that the maxima in wall shear stress and turbulent kinetic energy occur on the inner radius is therefore not an artifact of having introduced the sensor into the flow.« less

  10. CAA modeling of helicopter main rotor in hover

    NASA Astrophysics Data System (ADS)

    Kusyumov, Alexander N.; Mikhailov, Sergey A.; Batrakov, Andrey S.; Kusyumov, Sergey A.; Barakos, George

    In this work rotor aeroacoustics in hover is considered. Farfield observers are used and the nearfield flow parameters are obtained using the in house HMB and commercial Fluent CFD codes (identical hexa-grids are used for both solvers). Farfield noise at a remote observer position is calculated at post processing stage using FW-H solver implemented in Fluent and HMB. The main rotor of the UH-1H helicopter is considered as a test case for comparison to experimental data. The sound pressure level is estimated for different rotor blade collectives and observation angles.

  11. Preliminary Computational Fluid Dynamics (CFD) Simulation of EIIB Push Barge in Shallow Water

    NASA Astrophysics Data System (ADS)

    Beneš, Petr; Kollárik, Róbert

    2011-12-01

    This study presents preliminary CFD simulation of EIIb push barge in inland conditions using CFD software Ansys Fluent. The RANSE (Reynolds Averaged Navier-Stokes Equation) methods are used for the viscosity solution of turbulent flow around the ship hull. Different RANSE methods are used for the comparison of their results in ship resistance calculations, for selecting the appropriate and removing inappropriate methods. This study further familiarizes on the creation of geometrical model which considers exact water depth to vessel draft ratio in shallow water conditions, grid generation, setting mathematical model in Fluent and evaluation of the simulations results.

  12. Tribological characteristic enhancement effects by polymer thickened oil in lubricated sliding contacts

    NASA Astrophysics Data System (ADS)

    Pratomo, Ariawan Wahyu; Muchammad, Tauviqirrahman, Mohammad; Jamari, Bayuseno, Athanasius P.

    2016-04-01

    Polymer thickened oils are the most preferred materials for modern lubrication applications due to their high shear. The present paper explores a lubrication mechanism in sliding contact lubricated with polymer thickened oil considering cavitation. Investigations are carried out by using a numerical method based on commercial CFD (computational fluid dynamic) software ANSYS for fluid flow phenomenon (Fluent) to assess the tribological characteristic (i.e. hydrodynamic pressure distribution) of lubricated sliding contact. The Zwart-Gerber-Belamri model for cavitation is adopted in this simulation to predict the extent of the full film region. The polymer thickened oil is characterized as non-Newtonian power-law fluid. The simulation results show that the cavitation lead lower pressure profile compared to that without cavitation. In addition, it is concluded that the characteristic of the lubrication performance with polymer thickened oil is strongly dependent on the Power-law index of lubricant.

  13. Study of an array of two circular jets impinging on a flat surface

    NASA Astrophysics Data System (ADS)

    Simionescu, Ştefan-Mugur; Dhondoo, Nilesh; Bălan, Corneliu

    2018-02-01

    In this study, the flow characteristics of an array of two circular, laminar air jets impinging on a smooth solid wall are experimentally and numerically investigated. Direct visualizations using high speed/resolution camera are performed. The evolution of the vortical structures in the area where the jet is deflected from axial to radial direction is emphasized, as well as the interaction between the two jets. A set of CFD numerical simulations in 2D flow domains are performed by using the commercial software Fluent, in the context of Reynolds-averaged Navier-Stokes (RANS) modeling. The numerical resultsare compared and validated with the experiments. The vorticity number is computed and plotted at two different positions from the jet nozzle, and a study of its distribution gives a clue on how the jets are interacting with each other in the proximity of the solid wall.

  14. CFD analysis of hydrodynamic studies of a bubbling fluidized bed

    NASA Astrophysics Data System (ADS)

    Rao, B. J. M.; Rao, K. V. N. S.; Ranga Janardhana, G.

    2018-03-01

    Fluidization velocity is one of the most important parameter to characterize the hydrodynamic studies of fluidized bed asit determines different flow regimes. Computational Fluid Dynamics simulations are carriedfor a cylindrical bubbling fluidized bed with a static bed height 1m with 0.150m diameter of gasification chamber. The parameter investigated is fluidization velocity in range of 0.05m/s to 0.7m/s. Sand with density 2600kg/m3 and with a constant particle diameter of sand 385μm is employed for all the simulations. Simulations are conducted using the commercial Computational Fluid Dynamics software, ANSYS-FLUENT.The bubbling flow regime is appeared above the air inlet velocity of 0.2m/s. Bubbling character is increased with increase in inlet air velocities indicated by asymmetrical fluctuations of volume fractions in radial directions at different bed heights

  15. Determination of the oil distribution in a hermetic compressor using numerical simulation

    NASA Astrophysics Data System (ADS)

    Posch, S.; Hopfgartner, J.; Berger, E.; Zuber, B.; Almbauer, R.; Schöllauf, P.

    2017-08-01

    In addition to the reduction of friction the oil in a hermetic compressor is very important for the transfer of heat from hot parts to the compressor shell. The simulation of the oil distribution in a hermetic reciprocating compressor for refrigeration application is shown in the present work. Using the commercial Computational Fluid Dynamics (CFD) software ANSYS Fluent, the oil flow inside the compressor shell from the oil pump outlet to the oil sump is calculated. A comprehensive overview of the used models and the boundary conditions is given. After reaching steady-state conditions the oil covered surfaces are analysed concerning heat transfer coefficients. The gained heat transfer coefficients are used as input parameters for a thermal model of a hermetic compressor. An increase in accuracy of the thermal model with the simulated heat transfer coefficients compared to values from literature is shown by model validation with experimental data.

  16. RANS simulation of cavitation and hull pressure fluctuation for marine propeller operating behind-hull condition

    NASA Astrophysics Data System (ADS)

    Paik, Kwang-Jun; Park, Hyung-Gil; Seo, Jongsoo

    2013-12-01

    Simulations of cavitation flow and hull pressure fluctuation for a marine propeller operating behind a hull using the unsteady Reynolds-Averaged Navier-Stokes equations (RANS) are presented. A full hull body submerged under the free surface is modeled in the computational domain to simulate directly the wake field of the ship at the propeller plane. Simulations are performed in design and ballast draught conditions to study the effect of cavitation number. And two propellers with slightly different geometry are simulated to validate the detectability of the numerical simulation. All simulations are performed using a commercial CFD software FLUENT. Cavitation patterns of the simulations show good agreement with the experimental results carried out in Samsung CAvitation Tunnel (SCAT). The simulation results for the hull pressure fluctuation induced by a propeller are also compared with the experimental results showing good agreement in the tendency and amplitude, especially, for the first blade frequency.

  17. Verification of Advective Bar Elements Implemented in the Aria Thermal Response Code.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mills, Brantley

    2016-01-01

    A verification effort was undertaken to evaluate the implementation of the new advective bar capability in the Aria thermal response code. Several approaches to the verification process were taken : a mesh refinement study to demonstrate solution convergence in the fluid and the solid, visually examining the mapping of the advective bar element nodes to the surrounding surfaces, and a comparison of solutions produced using the advective bars for simple geometries with solutions from commercial CFD software . The mesh refinement study has shown solution convergence for simple pipe flow in both temperature and velocity . Guidelines were provided tomore » achieve appropriate meshes between the advective bar elements and the surrounding volume. Simulations of pipe flow using advective bars elements in Aria have been compared to simulations using the commercial CFD software ANSYS Fluent (r) and provided comparable solutions in temperature and velocity supporting proper implementation of the new capability. Verification of Advective Bar Elements iv Acknowledgements A special thanks goes to Dean Dobranich for his guidance and expertise through all stages of this effort . His advice and feedback was instrumental to its completion. Thanks also goes to Sam Subia and Tolu Okusanya for helping to plan many of the verification activities performed in this document. Thank you to Sam, Justin Lamb and Victor Brunini for their assistance in resolving issues encountered with running the advective bar element model. Finally, thanks goes to Dean, Sam, and Adam Hetzler for reviewing the document and providing very valuable comments.« less

  18. Numerical analysis of eccentric orifice plate using ANSYS Fluent software

    NASA Astrophysics Data System (ADS)

    Zahariea, D.

    2016-11-01

    In this paper the eccentric orifice plate is qualitative analysed as compared with the classical concentric orifice plate from the point of view of sedimentation tendency of solid particles in the fluid whose flow rate is measured. For this purpose, the numerical streamlines pattern will be compared for both orifice plates. The numerical analysis has been performed using ANSYS Fluent software. The methodology of CFD analysis is presented: creating the 3D solid model, fluid domain extraction, meshing, boundary condition, turbulence model, solving algorithm, convergence criterion, results and validation. Analysing the numerical streamlines, for the concentric orifice plate can be clearly observed two circumferential regions of separated flows, upstream and downstream of the orifice plate. The bottom part of these regions are the place where the solid particles could sediment. On the other hand, for the eccentric orifice plate, the streamlines pattern suggest that no sedimentation will occur because at the bottom area of the pipe there are no separated flows.

  19. Analysis of flow field characteristics in IC equipment chamber based on orthogonal design

    NASA Astrophysics Data System (ADS)

    Liu, W. F.; Yang, Y. Y.; Wang, C. N.

    2017-01-01

    This paper aims to study the influence of the configuration of processing chamber as a part of IC equipment on flow field characteristics. Four parameters, including chamber height, chamber diameter, inlet mass flow rate and outlet area, are arranged using orthogonally design method to study their influence on flow distribution in the processing chamber with the commercial software-Fluent. The velocity, pressure and temperature distribution above the holder were analysed respectively. The velocity difference value of the gas flow above the holder is defined as the evaluation criteria to evaluate the uniformity of the gas flow. The quantitative relationship between key parameters and the uniformity of gas flow was found through analysis of experimental results. According to our study, the chamber height is the most significant factor, and then follows the outlet area, chamber diameter and inlet mass flow rate. This research can provide insights into the study and design of configuration of etcher, plasma enhanced chemical vapor deposition (PECVD) equipment, and other systems with similar configuration and processing condition.

  20. Electroosmotic flow and Joule heating in preparative continuous annular electrochromatography.

    PubMed

    Laskowski, René; Bart, Hans-Jörg

    2015-09-01

    An openFOAM "computational fluid dynamic" simulation model was developed for the description of local interaction of hydrodynamics and Joule heating in annular electrochromatography. A local decline of electrical conductivity of the background eluent is caused by an electrokinetic migration of ions resulting in higher Joule heat generation. The model equations consider the Navier-Stokes equation for incompressible fluids, the energy equation for stationary temperature fields, and the mass transfer equation for the electrokinetic flow. The simulations were embedded in commercial ANSYS Fluent software and in open-source environment openFOAM. The annular gap (1 mm width) contained an inorganic C8 reverse-phase monolith as stationary phase prepared by an in situ sol-gel process. The process temperature generated by Joule heating was determined by thermal camera system. The local hydrodynamics in the prototype was detected by a gravimetric contact-free measurement method and experimental and simulated values matched quite well. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Numerical investigation of the thermal behavior of heated natural composite materials

    NASA Astrophysics Data System (ADS)

    Qasim, S. M.; Mohammed, F. Abbas; Hashim, R.

    2015-11-01

    In the present work numerical investigation was carried out for laminar natural convection heat transfer from natural composite material (NCM). Three types of natural materials such as seed dates, egg shells, and feathers are mixed separately with polyester resin. Natural materials are added with different volume fraction (10%, 20%, and 30%) are heated with different heat flux (1078W/m2, 928W/m2, 750W/m2, 608W/m2, and 457W/m2) at (vertical, inclined, and horizontal) position. Continuity and Navier-Stocks equations are solved numerically in three dimensions using ANSYS FLUENT package 12.1 software commercial program. Numerical results showed the temperature distribution was affected for all types at volume fraction 30% and heat flux is 1078 W/m2, for different position. So, shows that the plumes and temperature behavior are affected by the air and the distance from heat source. Numerical results showed acceptable agreement with the experimental previous results.

  2. Numerical investigation of solid mixing in a fluidized bed coating process

    NASA Astrophysics Data System (ADS)

    Kenche, Venkatakrishna; Feng, Yuqing; Ying, Danyang; Solnordal, Chris; Lim, Seng; Witt, Peter J.

    2013-06-01

    Fluidized beds are widely used in many process industries including the food and pharmaceutical sectors. Despite being an intensive research area, there are no design rules or correlations that can be used to quantitatively predict the solid mixing in a specific system for a given set of operating conditions. This paper presents a numerical study of the gas and solid dynamics in a laboratory scale fluidized bed coating process used for food and pharmaceutical industries. An Eulerian-Eulerian model (EEM) with kinetic theory of granular flow is selected as the modeling technique, with the commercial computational fluid dynamics (CFD) software package ANSYS/Fluent being the numerical platform. The flow structure is investigated in terms of the spatial distribution of gas and solid flow. The solid mixing has been evaluated under different operating conditions. It was found that the solid mixing rate in the horizontal direction is similar to that in the vertical direction under the current design and operating conditions. It takes about 5 s to achieve good mixing.

  3. Optimization of lamp arrangement in a closed-conduit UV reactor based on a genetic algorithm.

    PubMed

    Sultan, Tipu; Ahmad, Zeshan; Cho, Jinsoo

    2016-01-01

    The choice for the arrangement of the UV lamps in a closed-conduit ultraviolet (CCUV) reactor significantly affects the performance. However, a systematic methodology for the optimal lamp arrangement within the chamber of the CCUV reactor is not well established in the literature. In this research work, we propose a viable systematic methodology for the lamp arrangement based on a genetic algorithm (GA). In addition, we analyze the impacts of the diameter, angle, and symmetry of the lamp arrangement on the reduction equivalent dose (RED). The results are compared based on the simulated RED values and evaluated using the computational fluid dynamics simulations software ANSYS FLUENT. The fluence rate was calculated using commercial software UVCalc3D, and the GA-based lamp arrangement optimization was achieved using MATLAB. The simulation results provide detailed information about the GA-based methodology for the lamp arrangement, the pathogen transport, and the simulated RED values. A significant increase in the RED values was achieved by using the GA-based lamp arrangement methodology. This increase in RED value was highest for the asymmetric lamp arrangement within the chamber of the CCUV reactor. These results demonstrate that the proposed GA-based methodology for symmetric and asymmetric lamp arrangement provides a viable technical solution to the design and optimization of the CCUV reactor.

  4. Amelioration du design et prediction des vitesses moyennes de sortie de buses a jet coherent pour les procedes de rectification a l'aide de la CFD

    NASA Astrophysics Data System (ADS)

    St-Pierre, Benoit

    In order to produce more efficient jet engines, manufacturers add compressor stages to their new engines and their manufacturing departments must increase their productivity while reducing their costs of operation. The addition of these compressor stages causes an increase in the pressures and temperatures for those components. To address this issue, the engineering departments use highly thermal resistant alloys for their manufacturing, mostly nickel alloys. However, these alloys are very difficult to machine by conventional manufacturing processes. Thus, in order to efficiently machine these alloys, grinding processes, like Continuous Dress Creep Feed (CDCF), are always the best choices. However, the productivity of these processes is mainly limited by the burning marks that may appear on the machined surfaces if too aggressive cutting parameters are selected. A simple solution to this issue consists in improving the design of the existing coherent coolant nozzle so that they can produce an even more coherent coolant jet. Therefore, this research project proposes a method which makes it possible to predict the jet coherency of a given nozzle while also giving the possibility to optimize its design in order to improve its jet coherency and all that while using a commercial CFD software, i.e. FLUENT 6.3. Thus, the proposed method is based on the evolution of the velocity profile provided by FLUENT for a given Webster type nozzle and on the experimental measurement of jet coherency of this one in order to establish a semi-empirical model that links these two results. So, for a given nozzle it is possible to precisely predict the physical opening of the coolant jet that this one will produce by using the opening of the velocity profile provided by FLUENT and the semiempirical model developed in this research. The use of FLUENT fonctions also made it possible to simulate the fluid flow inside the coolant nozzle and to identify the cavitation zones within it in order to decrease its importance by modifying the inside profile geometry. This new design of coolant nozzle is more able to produce a coherent jet as compared to the Webster type design. Moreover, this was verified using the semi-empirical model developed in this research and then validated through experimental tests. Finally, cutting tests were performed to compare Webster type nozzle against the newly proposed coolant nozzle design. The results obtained show that the new concept of coolant nozzle gives an improvement in wheel life of more than 15% while slightly decreasing the power required for a cut and that's while preserving a similar surface finish. Finally, a comparative study between FLUENT and Bernoulli equations for the prediction of the mean velocity at the nozzle exit is carried out. This comparison shows that neglecting the effect of turbulence and cavitations on the coolant flow greatly influences the mean velocity at the nozzle exit.

  5. Numerical simulation study on the distribution law of smoke flow velocity in horizontal tunnel fire

    NASA Astrophysics Data System (ADS)

    Liu, Yejiao; Tian, Zhichao; Xue, Junhua; Wang, Wencai

    2018-02-01

    According to the fluid similarity theory, the simulation experiment system of mining tunnel fire is established. The grid division of experimental model roadway is carried on by GAMBIT software. By setting the boundary and initial conditions of smoke flow during fire period in FLUENT software, using RNG k-Ɛ two-equation turbulence model, energy equation and SIMPLE algorithm, the steady state numerical simulation of smoke flow velocity in mining tunnel is done to obtain the distribution law of smoke flow velocity in tunnel during fire period.

  6. How Reading Volume Affects Both Reading Fluency and Reading Achievement

    ERIC Educational Resources Information Center

    Allington, Richard L.

    2014-01-01

    Long overlooked, reading volume is actually central to the development of reading proficiencies, especially in the development of fluent reading proficiency. Generally no one in schools monitors the actual volume of reading that children engage in. We know that the commonly used commercial core reading programs provide only material that requires…

  7. Evaluation of Cooling Conditions for a High Heat Flux Testing Facility Based on Plasma-Arc Lamps

    DOE PAGES

    Charry, Carlos H.; Abdel-khalik, Said I.; Yoda, Minami; ...

    2015-07-31

    The new Irradiated Material Target Station (IMTS) facility for fusion materials at Oak Ridge National Laboratory (ORNL) uses an infrared plasma-arc lamp (PAL) to deliver incident heat fluxes as high as 27 MW/m 2. The facility is being used to test irradiated plasma-facing component materials as part of the joint US-Japan PHENIX program. The irradiated samples are to be mounted on molybdenum sample holders attached to a water-cooled copper rod. Depending on the size and geometry of samples, several sample holders and copper rod configurations have been fabricated and tested. As a part of the effort to design sample holdersmore » compatible with the high heat flux (HHF) testing to be conducted at the IMTS facility, numerical simulations have been performed for two different water-cooled sample holder designs using the ANSYS FLUENT 14.0 commercial computational fluid dynamics (CFD) software package. The primary objective of this work is to evaluate the cooling capability of different sample holder designs, i.e. to estimate their maximum allowable incident heat flux values. 2D axisymmetric numerical simulations are performed using the realizable k-ε turbulence model and the RPI nucleate boiling model within ANSYS FLUENT 14.0. The results of the numerical model were compared against the experimental data for two sample holder designs tested in the IMTS facility. The model has been used to parametrically evaluate the effect of various operational parameters on the predicted temperature distributions. The results were used to identify the limiting parameter for safe operation of the two sample holders and the associated peak heat flux limits. The results of this investigation will help guide the development of new sample holder designs.« less

  8. Simulation of concentration distribution of urban particles under wind

    NASA Astrophysics Data System (ADS)

    Chen, Yanghou; Yang, Hangsheng

    2018-02-01

    The concentration of particulate matter in the air is too high, which seriously affects people’s health. The concentration of particles in densely populated towns is also high. Understanding the distribution of particles in the air helps to remove them passively. The concentration distribution of particles in urban streets is simulated by using the FLUENT software. The simulation analysis based on Discrete Phase Modelling (DPM) of FLUENT. Simulation results show that the distribution of the particles is caused by different layout of buildings. And it is pointed out that in the windward area of the building and the leeward sides of the high-rise building are the areas with high concentration of particles. Understanding the concentration of particles in different areas is also helpful for people to avoid and reduce the concentration of particles in high concentration areas.

  9. Numerical study of rice husk and coal co-combustion characteristics in a circulating fluidized bed

    NASA Astrophysics Data System (ADS)

    Wang, Zuomin; Li, Jiuru

    2018-02-01

    This paper discussed the rationality of coal and rice husk co-combustion. Using ICEM software, a two-dimensional model of the riser has been established for circulating fluidized bed experimental table. Using Fluent software, numerical simulation has been made for the combustion reaction of different proportions of rice husk mixed with coal. The results show that, with the increase of rice husk ratio, both the combustion temperature and the amount of nitrogen oxides decrease and the effect is gradually reduced. In this simulation, the rice husks occupying about 30% is a reasonable proportion.

  10. Optimization of polymer electrolyte membrane fuel cell flow channels using a genetic algorithm

    NASA Astrophysics Data System (ADS)

    Catlin, Glenn; Advani, Suresh G.; Prasad, Ajay K.

    The design of the flow channels in PEM fuel cells directly impacts the transport of reactant gases to the electrodes and affects cell performance. This paper presents results from a study to optimize the geometry of the flow channels in a PEM fuel cell. The optimization process implements a genetic algorithm to rapidly converge on the channel geometry that provides the highest net power output from the cell. In addition, this work implements a method for the automatic generation of parameterized channel domains that are evaluated for performance using a commercial computational fluid dynamics package from ANSYS. The software package includes GAMBIT as the solid modeling and meshing software, the solver FLUENT, and a PEMFC Add-on Module capable of modeling the relevant physical and electrochemical mechanisms that describe PEM fuel cell operation. The result of the optimization process is a set of optimal channel geometry values for the single-serpentine channel configuration. The performance of the optimal geometry is contrasted with a sub-optimal one by comparing contour plots of current density, oxygen and hydrogen concentration. In addition, the role of convective bypass in bringing fresh reactant to the catalyst layer is examined in detail. The convergence to the optimal geometry is confirmed by a bracketing study which compares the performance of the best individual to those of its neighbors with adjacent parameter values.

  11. Effect of jet-mainstream velocity ratio on flow characteristics and heat transfer enhancement of jet on flat plate flow

    NASA Astrophysics Data System (ADS)

    Puzu, N.; Prasertsan, S.; Nuntadusit, C.

    2017-09-01

    The aim of this research was to study the effect of jet-mainstream velocity ratio on flow and heat transfer characteristics of jet on flat plate flow. The jet from pipe nozzle with inner diameter of D=14 mm was injected perpendicularly to mainstream on flat plate. The flat plate was blown by mainstream with uniform velocity profile at 10 m/s. The velocity ratio (jet to mainstream velociy) was varied at VR=0.25 and 3.5 by adjusting velocity of jet flow. For heat transfer measurement, a thin foil technique was used to evaluate the heat transfer coefficient by measuring temperature distributions on heat transfer surface with constant heat flux by using infrared camera. Flow characteristics were simulated by using a computational fluid dynamics (CFD) with commercial software ANSYS Fluent (Ver.15.0). The results showed that the enhancement of heat transfer along downstream direction for the case of VR=0.25 was from the effect of jet stream whereas for the case of VR=3.5 was from the effect of mainstream.

  12. CFD simulation of gas and non-Newtonian fluid two-phase flow in anaerobic digesters.

    PubMed

    Wu, Binxin

    2010-07-01

    This paper presents an Eulerian multiphase flow model that characterizes gas mixing in anaerobic digesters. In the model development, liquid manure is assumed to be water or a non-Newtonian fluid that is dependent on total solids (TS) concentration. To establish the appropriate models for different TS levels, twelve turbulence models are evaluated by comparing the frictional pressure drops of gas and non-Newtonian fluid two-phase flow in a horizontal pipe obtained from computational fluid dynamics (CFD) with those from a correlation analysis. The commercial CFD software, Fluent12.0, is employed to simulate the multiphase flow in the digesters. The simulation results in a small-sized digester are validated against the experimental data from literature. Comparison of two gas mixing designs in a medium-sized digester demonstrates that mixing intensity is insensitive to the TS in confined gas mixing, whereas there are significant decreases with increases of TS in unconfined gas mixing. Moreover, comparison of three mixing methods indicates that gas mixing is more efficient than mixing by pumped circulation while it is less efficient than mechanical mixing.

  13. 2D simulation of active species and ozone production in a multi-tip DC air corona discharge

    NASA Astrophysics Data System (ADS)

    Meziane, M.; Eichwald, O.; Sarrette, J. P.; Ducasse, O.; Yousfi, M.

    2011-11-01

    The present paper shows for the first time in the literature a complete 2D simulation of the ozone production in a DC positive multi-tip to plane corona discharge reactor crossed by a dry air flow at atmospheric pressure. The simulation is undertaken until 1 ms and involves tens of successive discharge and post-discharge phases. The air flow is stressed by several monofilament corona discharges generated by a maximum of four anodic tips distributed along the reactor. The nonstationary hydrodynamics model for reactive gas mixture is solved using the commercial FLUENT software. During each discharge phase, thermal and vibrational energies as well as densities of radical and metastable excited species are locally injected as source terms in the gas medium surrounding each tip. The chosen chemical model involves 10 neutral species reacting following 24 reactions. The obtained results allow us to follow the cartography of the temperature and the ozone production inside the corona reactor as a function of the number of high voltage anodic tips.

  14. Evaluation of Liquid Fuel Spray Models for Hybrid RANS/LES and DLES Prediction of Turbulent Reactive Flows

    NASA Astrophysics Data System (ADS)

    Afshar, Ali

    An evaluation of Lagrangian-based, discrete-phase models for multi-component liquid sprays encountered in the combustors of gas turbine engines is considered. In particular, the spray modeling capabilities of the commercial software, ANSYS Fluent, was evaluated. Spray modeling was performed for various cold flow validation cases. These validation cases include a liquid jet in a cross-flow, an airblast atomizer, and a high shear fuel nozzle. Droplet properties including velocity and diameter were investigated and compared with previous experimental and numerical results. Different primary and secondary breakup models were evaluated in this thesis. The secondary breakup models investigated include the Taylor analogy breakup (TAB) model, the wave model, the Kelvin-Helmholtz Rayleigh-Taylor model (KHRT), and the Stochastic secondary droplet (SSD) approach. The modeling of fuel sprays requires a proper treatment for the turbulence. Reynolds-averaged Navier-Stokes (RANS), large eddy simulation (LES), hybrid RANS/LES, and dynamic LES (DLES) were also considered for the turbulent flows involving sprays. The spray and turbulence models were evaluated using the available benchmark experimental data.

  15. Suppression/Reversal of Natural Convection by Exploiting the Temperature/Composition Dependence of Magnetic Susceptibility

    NASA Technical Reports Server (NTRS)

    Seybert, C. D.; Evans, J. W.; Leslie, F.; Jones, W. K., Jr.

    2000-01-01

    Natural convection, driven by temperature-or concentration gradients or both, is an inherent phenomenon during solidification of materials on Earth. This convection has practical consequences (e.g effecting macrosegregation) but also renders difficult the scientific examination of diffusive/conductive phenomena during solidification. It is possible to halt, or even reverse, natural convection by exploiting the variation (with temperature, for example) of the susceptibility of a material. If the material is placed in a vertical magnetic field gradient, a buoyancy force of magnetic origin arises and, at a critical field gradient, can balance the normal buoyancy forces to halt convection. At higher field gradients the convection can be reversed. The effect has been demonstrated in experiments at Marshall Space Flight Center where flow was measured by PIV in MnCl2 solution in a superconducting magnet. In auxiliary experiments the field in the magnet and the properties of the solution were measured. Computations of the natural convection, its halting and reversal, using the commercial software FLUENT were in good agreement with the measurements.

  16. Study the velocity and pressure exerted in front of the filter surface in the kitchen hood system by using ANSYS

    NASA Astrophysics Data System (ADS)

    Asmuin, Norzelawati; Pairan, M. Rasidi; Isa, Norasikin Mat; Sies, Farid

    2017-04-01

    Commercial kitchen hood ventilation system is a device used to capture and filtered the plumes from cooking activities in the kitchen area. Nowadays, it is very popular in the industrial sector such as restaurant and hotel to provide hygiene food. This study focused at the KSA filter part which installed in the kitchen hood system, the purpose of this study is to identify the critical region which indicated by observing the velocity and pressure of plumes exerted at of KSA filter. It is important to know the critical location of the KSA filter in order to install the nozzle which will helps increase the filtration effectiveness. The ANSYS 16.1 (FLUENT) software as a tool used to simulate the kitchen hood systems which consist of KSA filter. The commercial kitchen hood system model has a dimension 700 mm width, 1600 mm length and 555 mm height. The system has two inlets and one outlet. The velocity of the plumes is set to be 0.235m/s and the velocity of the inlet capture jet is set to be 1.078m/s. The KSA filter is placed 45 degree from the y axis. The result shows the plumes has more tendency flowing pass through at the bottom part of KSA filter.

  17. 48 CFR 227.7202 - Commercial computer software and commercial computer software documentation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... software and commercial computer software documentation. 227.7202 Section 227.7202 Federal Acquisition... REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202 Commercial computer software and commercial computer software documentation. ...

  18. 48 CFR 227.7202 - Commercial computer software and commercial computer software documentation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... software and commercial computer software documentation. 227.7202 Section 227.7202 Federal Acquisition... REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202 Commercial computer software and commercial computer software documentation. ...

  19. 48 CFR 227.7202 - Commercial computer software and commercial computer software documentation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... software and commercial computer software documentation. 227.7202 Section 227.7202 Federal Acquisition... REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202 Commercial computer software and commercial computer software documentation. ...

  20. 48 CFR 227.7202 - Commercial computer software and commercial computer software documentation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... software and commercial computer software documentation. 227.7202 Section 227.7202 Federal Acquisition... REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202 Commercial computer software and commercial computer software documentation. ...

  1. 48 CFR 227.7202 - Commercial computer software and commercial computer software documentation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... software and commercial computer software documentation. 227.7202 Section 227.7202 Federal Acquisition... REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202 Commercial computer software and commercial computer software documentation. ...

  2. Study on cavitation effect of mechanical seals with laser-textured porous surface

    NASA Astrophysics Data System (ADS)

    Liu, T.; Chen, H. l.; Liu, Y. H.; Wang, Q.; Liu, Z. B.; Hou, D. H.

    2012-11-01

    Study on the mechanisms underlying generation of hydrodynamic pressure effect associated with laser-textured porous surface on mechanical seal, is the key to seal and lubricant properties. The theory model of mechanical seals with laser-textured porous surface (LES-MS) based on cavitation model was established. The LST-MS was calculated and analyzed by using Fluent software with full cavitation model and non-cavitation model and film thickness was predicted by the dynamic mesh technique. The results indicate that the effect of hydrodynamic pressure and cavitation are the important reasons to generate liquid film opening force on LST-MS; Cavitation effect can enhance hydrodynamic pressure effect of LST-MS; The thickness of liquid film could be well predicted with the method of dynamic mesh technique on Fluent and it becomes larger as the increasing of shaft speed and the decreasing of pressure.

  3. 48 CFR 227.7202-3 - Rights in commercial computer software or commercial computer software documentation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... computer software or commercial computer software documentation. 227.7202-3 Section 227.7202-3 Federal... CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202-3 Rights in commercial computer software or commercial computer software documentation...

  4. 48 CFR 227.7202-3 - Rights in commercial computer software or commercial computer software documentation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... computer software or commercial computer software documentation. 227.7202-3 Section 227.7202-3 Federal... CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202-3 Rights in commercial computer software or commercial computer software documentation...

  5. 48 CFR 227.7202-3 - Rights in commercial computer software or commercial computer software documentation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... computer software or commercial computer software documentation. 227.7202-3 Section 227.7202-3 Federal... CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202-3 Rights in commercial computer software or commercial computer software documentation...

  6. 48 CFR 227.7202-3 - Rights in commercial computer software or commercial computer software documentation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... computer software or commercial computer software documentation. 227.7202-3 Section 227.7202-3 Federal... CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202-3 Rights in commercial computer software or commercial computer software documentation...

  7. 48 CFR 227.7202-3 - Rights in commercial computer software or commercial computer software documentation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... computer software or commercial computer software documentation. 227.7202-3 Section 227.7202-3 Federal... CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202-3 Rights in commercial computer software or commercial computer software documentation...

  8. Numerical simulation of a flow past a triangular sail-type blade of a wind generator using the ANSYS FLUENT software package

    NASA Astrophysics Data System (ADS)

    Kusaiynov, K.; Tanasheva, N. K.; Min'kov, L. L.; Nusupbekov, B. R.; Stepanova, Yu. O.; Rozhkova, A. V.

    2016-02-01

    An air flow past a single triangular sail-type blade of a wind turbine is analyzed by numerical simulation for low velocities of the incoming flow. The results of numerical simulation indicate a monotonic increase in the drag force and the lift force as functions of the incoming flow; empirical dependences of these quantities are obtained.

  9. Numerical Analysis of the Cavity Flow subjected to Passive Controls Techniques

    NASA Astrophysics Data System (ADS)

    Melih Guleren, Kursad; Turk, Seyfettin; Mirza Demircan, Osman; Demir, Oguzhan

    2018-03-01

    Open-source flow solvers are getting more and more popular for the analysis of challenging flow problems in aeronautical and mechanical engineering applications. They are offered under the GNU General Public License and can be run, examined, shared and modified according to user’s requirements. SU2 and OpenFOAM are the two most popular open-source solvers in Computational Fluid Dynamics (CFD) community. In the present study, some passive control methods on the high-speed cavity flows are numerically simulated using these open-source flow solvers along with one commercial flow solver called ANSYS/Fluent. The results are compared with the available experimental data. The solver SU2 are seen to predict satisfactory the mean streamline velocity but not turbulent kinetic energy and overall averaged sound pressure level (OASPL). Whereas OpenFOAM predicts all these parameters nearly as the same levels of ANSYS/Fluent.

  10. 48 CFR 12.212 - Computer software.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 1 2012-10-01 2012-10-01 false Computer software. 12.212... software. (a) Commercial computer software or commercial computer software documentation shall be acquired... required to— (1) Furnish technical information related to commercial computer software or commercial...

  11. 48 CFR 12.212 - Computer software.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Computer software. 12.212... software. (a) Commercial computer software or commercial computer software documentation shall be acquired... required to— (1) Furnish technical information related to commercial computer software or commercial...

  12. 48 CFR 12.212 - Computer software.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Computer software. 12.212... software. (a) Commercial computer software or commercial computer software documentation shall be acquired... required to— (1) Furnish technical information related to commercial computer software or commercial...

  13. 48 CFR 12.212 - Computer software.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Computer software. 12.212... software. (a) Commercial computer software or commercial computer software documentation shall be acquired... required to— (1) Furnish technical information related to commercial computer software or commercial...

  14. 48 CFR 12.212 - Computer software.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Computer software. 12.212... software. (a) Commercial computer software or commercial computer software documentation shall be acquired... required to— (1) Furnish technical information related to commercial computer software or commercial...

  15. LEM-CF Premixed Tool Kit

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    2015-01-19

    The purpose of LEM-CF Premixed Tool Kit is to process premixed flame simulation data from the LEM-CF solver (https://fileshare.craft-tech.com/clusters/view/lem-cf) into a large-eddy simulation (LES) subgrid model database. These databases may be used with a user-defined-function (UDF) that is included in the Tool Kit. The subgrid model UDF may be used with the ANSYS FLUENT flow solver or other commercial flow solvers.

  16. CFD Simulation of a Wing-In-Ground-Effect UAV

    NASA Astrophysics Data System (ADS)

    Lao, C. T.; Wong, E. T. T.

    2018-05-01

    This paper reports a numerical analysis on a wing section used for a Wing-In-Ground-Effect (WIG) unmanned aerial vehicle (UAV). The wing geometry was created by SolidWorks and the incompressible Reynolds-averaged Navier-Stokes (RANS) equations were solved with the Spalart–Allmaras turbulence model using CFD software ANSYS FLUENT. In FLUENT, the Spalart-Allmaras model has been implemented to use wall functions when the mesh resolution is not sufficiently fine. This might make it the best choice for relatively crude simulations on coarse meshes where accurate turbulent flow computations are not critical. The results show that the lift coefficient and lift-drag ratio derived excellent performance enhancement by ground effect. However, the moment coefficient shows inconsistency when the wing is operating in very low altitude - this is owing to the difficulty on the stability control of WIG vehicle. A drag polar estimation based on the analysis also indicated that the Oswald (or span) efficiency of the wing was improved by ground effect.

  17. Experimental and numerical simulation of passive decay heat removal by sump cooling after cool melt down

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Knebel, J.U.; Kuhn, D.; Mueller, U.

    1997-12-01

    This article presents the basic physical phenomena and scaling criteria of passive decay heat removal from a large coolant pool by single-phase and two-phase natural circulation. The physical significance of the dimensionless similarity groups derived is evaluated. The above results are applied to the SUCO program that is performed at the Forschungszentrum Karlsruhe. The SUCO program is a three-step series of scaled model experiments investigating the possibility of a sump cooling concept for future light water reactors. The sump cooling concept is based on passive safety features within the containment. The work is supported by the German utilities and themore » Siemens AG. The article gives results of temperature and velocity measurements in the 1:20 linearly scaled SUCOS-2D test facility. The experiments are backed up by numerical calculations using the commercial software package Fluent. Finally, using the similarity analysis from above, the experimental results of the model geometry are scaled-up to the conditions in the prototype, allowing a first statement with regard to the feasibility of the sump cooling concept. 11 refs., 9 figs., 3 tabs.« less

  18. A comparative study on the motion of various objects inside an air tunnel

    NASA Astrophysics Data System (ADS)

    Shibani, Wanis Mustafa E.; Zulkafli, Mohd Fadhli; Basunoand, Bambang

    2017-04-01

    This paper presents a comparative study of the movement of various rigid bodies through an air tunnel for both two and three-dimensional flow problems. Three kinds of objects under investigation are in the form of box, ball and wedge shape. The investigation was carried out through the use of a commercial CFD software, named Fluent, in order to determine aerodynamic forces, act on the object as well as to track its movement. Adopted numerical scheme is the time-averaged Navier-Stokes equation with k - ɛ as its turbulence modeling and the scheme was solved using the SIMPLE algorithm. Triangular elements grid was used in 2D case, while tetrahedron elements for 3D case. Grid independence studies were performed for each problem from a coarse to fine grid. The motion of an object is restricted in one direction only and is found by tracking its center of mass at every time step. The result indicates the movement of the object is increasing as the flow moves down stream and the box have the fastest speed compare to the other two shapes for both 2D and 3D cases.

  19. Numerical and experimental investigation of enhancement of heat transfer in dimpled rib heat exchanger tube

    NASA Astrophysics Data System (ADS)

    Kumar, Anil; Maithani, Rajesh; Suri, Amar Raj Singh

    2017-12-01

    In this study, numerical and experimental investigation has been carried out for a range of system and operating parameters in order to analyse the effect of dimpled rib on heat and fluid flow behaviours in heat exchanger tube. Tube has, stream wise spacing ( x/ d d ) range of 15-35, span wise spacing ( y/ d d ) range of 15-35, ratio of dimpled depth to print diameter ( e/ d d ) of 1.0 and Reynolds number ( Re n ) ranges from 4000 to 28,000. Simulations were carried out to obtain heat and fluid flow behaviour of smooth and rough tube, using commercial CFD software, ANSYS 16.0 (Fluent). Renormalization k - ɛ model was employed to assess the influence of dimpled on turbulent flow and velocity field. Simulation results show that, the enhancement of 3.18 times in heat transfer and 2.87 times enhancement in thermal hydraulic performance as a function of stream wise direction ( x/ d d ) of 15 and span wise direction ( y/ d d ) of 15 respectively. Comparison between numerical and experimental simulation results showed that good agreement as the data fell within ±10% error band.

  20. Modeling and validation of heat and mass transfer in individual coffee beans during the coffee roasting process using computational fluid dynamics (CFD).

    PubMed

    Alonso-Torres, Beatriz; Hernández-Pérez, José Alfredo; Sierra-Espinoza, Fernando; Schenker, Stefan; Yeretzian, Chahan

    2013-01-01

    Heat and mass transfer in individual coffee beans during roasting were simulated using computational fluid dynamics (CFD). Numerical equations for heat and mass transfer inside the coffee bean were solved using the finite volume technique in the commercial CFD code Fluent; the software was complemented with specific user-defined functions (UDFs). To experimentally validate the numerical model, a single coffee bean was placed in a cylindrical glass tube and roasted by a hot air flow, using the identical geometrical 3D configuration and hot air flow conditions as the ones used for numerical simulations. Temperature and humidity calculations obtained with the model were compared with experimental data. The model predicts the actual process quite accurately and represents a useful approach to monitor the coffee roasting process in real time. It provides valuable information on time-resolved process variables that are otherwise difficult to obtain experimentally, but critical to a better understanding of the coffee roasting process at the individual bean level. This includes variables such as time-resolved 3D profiles of bean temperature and moisture content, and temperature profiles of the roasting air in the vicinity of the coffee bean.

  1. Modeling of diesel/CNG mixing in a pre-injection chamber

    NASA Astrophysics Data System (ADS)

    Abdul-Wahhab, H. A.; Aziz, A. R. A.; Al-Kayiem, H. H.; Nasif, M. S.

    2015-12-01

    Diesel engines performance can be improved by adding combustible gases to the liquid diesel. In this paper, the propagation of a two phase flow liquid-gas fuel mixture into a pre-mixer is investigated numerically by computational fluid dynamics simulation. CNG was injected into the diesel within a cylindrical conduit operates as pre-mixer. Four injection models of Diesel-CNG were simulated using ANSYS-FLUENT commercial software. Two CNG jet diameters were used of 1 and 2 mm and the diesel pipe diameter was 9 mm. Two configurations were considered for the gas injection. In the first the gas was injected from one side while for the second two side entries were used. The CNG to Diesel pressure ratio was varied between 1.5 and 3. The CNG to Diesel mass flow ratios were varied between 0.7 and 0.9. The results demonstrate that using double-sided injection increased the homogeneity of the mixture due to the swirl and acceleration of the mixture. Mass fraction, in both cases, was found to increase as the mixture flows towards the exit. As a result, this enhanced mixing is likely to lead to improvement in the combustion performance.

  2. Analyse et design aerodynamique haute-fidelite de l'integration moteur sur un avion BWB

    NASA Astrophysics Data System (ADS)

    Mirzaei Amirabad, Mojtaba

    BWB (Blended Wing Body) is an innovative type of aircraft based on the flying wing concept. In this configuration, the wing and the fuselage are blended together smoothly. BWB offers economical and environmental advantages by reducing fuel consumption through improving aerodynamic performance. In this project, the goal is to improve the aerodynamic performance by optimizing the main body of BWB that comes from conceptual design. The high fidelity methods applied in this project have been less frequently addressed in the literature. This research develops an automatic optimization procedure in order to reduce the drag force on the main body. The optimization is carried out in two main stages: before and after engine installation. Our objective is to minimize the drag by taking into account several constraints in high fidelity optimization. The commercial software, Isight is chosen as an optimizer in which MATLAB software is called to start the optimization process. Geometry is generated using ANSYS-DesignModeler, unstructured mesh is created by ANSYS-Mesh and CFD calculations are done with the help of ANSYS-Fluent. All of these software are coupled together in ANSYS-Workbench environment which is called by MATLAB. The high fidelity methods are used during optimization by solving Navier-Stokes equations. For verifying the results, a finer structured mesh is created by ICEM software to be used in each stage of optimization. The first stage includes a 3D optimization on the surface of the main body, before adding the engine. The optimized case is then used as an input for the second stage in which the nacelle is added. It could be concluded that this study leads us to obtain appropriate reduction in drag coefficient for BWB without nacelle. In the second stage (adding the nacelle) a drag minimization is also achieved by performing a local optimization. Furthermore, the flow separation, created in the main body-nacelle zone, is reduced.

  3. 48 CFR 239.101 - Policy.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    .... See Subpart 208.74 when acquiring commercial software or software maintenance. See 227.7202 for policy on the acquisition of commercial computer software and commercial computer software documentation...

  4. 48 CFR 239.101 - Policy.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    .... See Subpart 208.74 when acquiring commercial software or software maintenance. See 227.7202 for policy on the acquisition of commercial computer software and commercial computer software documentation...

  5. 48 CFR 239.101 - Policy.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    .... See Subpart 208.74 when acquiring commercial software or software maintenance. See 227.7202 for policy on the acquisition of commercial computer software and commercial computer software documentation...

  6. 48 CFR 239.101 - Policy.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    .... See Subpart 208.74 when acquiring commercial software or software maintenance. See 227.7202 for policy on the acquisition of commercial computer software and commercial computer software documentation...

  7. 48 CFR 239.101 - Policy.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    .... See Subpart 208.74 when acquiring commercial software or software maintenance. See 227.7202 for policy on the acquisition of commercial computer software and commercial computer software documentation...

  8. Stuttered and Fluent Speakers' Heart Rate and Skin Conductance in Response to Fluent and Stuttered Speech

    ERIC Educational Resources Information Center

    Zhang, Jianliang; Kalinowski, Joseph; Saltuklaroglu, Tim; Hudock, Daniel

    2010-01-01

    Background: Previous studies have found simultaneous increases in skin conductance response and decreases in heart rate when normally fluent speakers watched and listened to stuttered speech compared with fluent speech, suggesting that stuttering induces arousal and emotional unpleasantness in listeners. However, physiological responses of persons…

  9. Fluent Aphasia in Telugu: A Case Comparison Study of Semantic Dementia and Stroke Aphasia

    ERIC Educational Resources Information Center

    Alladi, Suvarna; Mridula, Rukmini; Mekala, Shailaja; Rupela, Vani; Kaul, Subhash

    2010-01-01

    This study presents two cases with fluent aphasia in Telugu with semantic dementia and post-stroke fluent aphasia. Comparable scores were obtained on the conventional neuropsychological and language tests that were administered on the two cases. Both cases demonstrated fluent, grammatical and well-articulated speech with little content, impaired…

  10. Analysis of particle size to erosion wear of sliding sleeve ball seat based on fluent software

    NASA Astrophysics Data System (ADS)

    Ding, Kun; Yin, Hongcheng; Wan, Bingqian; Cheng, Hao; Xiang, Lu; Li, Jianmin

    2017-04-01

    The fracturing has become the most offensive stimulation treatment in the low permeability reservoir. But, as the construction displacement and sand dosage of overlong horizontal well were increased continuously, the erosion wear of ball seat of pitching sliding sleeve was increasingly serious, which might lead to the failure of opening the sliding sleeve. In the existing literature, there were many researches on the erosion wear of liquid-solid two-phase flow in the diameter of sudden expansion pipe, but the influence of solid particle with mixed particle size to the erosion wear was not considered. This paper studied the erosion wear of ball seat according to the mixed proppant with different particle sizes, and carried out the numerical simulation with Fluent software with the Euler two-fluid theory. The results showed that: the erosion wear rate of ball seat is in inversely proportional to the particle size of proppant; the erosion wear rate of ball seat is different when the volume fraction of proppant with different particle sizes is changed; and for the mixed proppant of which the particle size is 0.3mm and 0.8mm, the erosion wear rate of ball seat is minimum when the volume fraction of proppant, of which the particle size is 0.3mm, is about 20%. The simulated result contributed to the deep study on erosion wear law of solid particle, and meanwhile, provided a certain reference basis for the selection of staged fracturing material of horizontal well.

  11. Study of scattering from turbulence structure generated by propeller with FLUENT

    NASA Astrophysics Data System (ADS)

    Luo, Gen

    2017-07-01

    In this article, the turbulence structure generated by a propeller is simulated with the computational fluid dynamics (CFD) software FLUENT. With the method of moments, the backscattering radar cross sections (RCS) of the turbulence structure are calculated. The scattering results can reflect the turbulent intensity of the wave profiles. For the wake turbulence with low rotating speed, the scattering intensity of HH polarization is much smaller than VV polarization at large incident angles. When the turbulence becomes stronger with high rotating speed, the scattering intensity of HH polarization also becomes stronger at large incident angles, which is almost the same with VV polarization. And also, the bistatic scattering of the turbulence structure has the similar situation. These scattering results indicate that the turbulence structure can also give rise to an anomaly compared with traditional sea surface. The study of electromagnetic (EM) scattering from turbulence structure generated by the propeller can help in better understanding of the scattering from different kinds of waves and provide more bases to explain the anomalies of EM scattering from sea surfaces.

  12. Analysis of artery blood flow before and after angioplasty

    NASA Astrophysics Data System (ADS)

    Tomaszewski, Michał; Baranowski, Paweł; Małachowski, Jerzy; Damaziak, Krzysztof; Bukała, Jakub

    2018-01-01

    The study presents a comparison of results obtained from numerical simulations of blood flow in two different arteries. One of them was considered to be narrowed in order to simulate an arteriosclerosis obstructing the blood flow in the vessel, whereas the second simulates the vessel after angioplasty treatment. During the treatment, a biodegradable stent is inserted into the artery, which prevents the vessel walls from collapsing. The treatment was simulated through the use of numerical simulation using the finite element method. The final mesh geometry obtained from the analysis was exported to the dedicated software in order to create geometry in which a flow domain inside the artery with the stent was created. The flow analysis was conducted in ANSYS Fluent software with non-deformable vessel walls.

  13. Numerical analysis of thermal creep flow in curved channels for designing a prototype of Knudsen micropump

    NASA Astrophysics Data System (ADS)

    Leontidis, V.; Brandner, J. J.; Baldas, L.; Colin, S.

    2012-05-01

    The possibility to generate a gas flow inside a channel just by imposing a tangential temperature gradient along the walls without the existence of an initial pressure difference is well known. The gas must be under rarefied conditions, meaning that the system must operate between the slip and the free molecular flow regimes, either at low pressure or/and at micro/nano-scale dimensions. This phenomenon is at the basis of the operation principle of Knudsen pumps, which are actually compressors without any moving parts. Nowadays, gas flows in the slip flow regime through microchannels can be modeled using commercial Computational Fluid Dynamics softwares, because in this regime the compressible Navier-Stokes equations with appropriate boundary conditions are still valid. A simulation procedure has been developed for the modeling of thermal creep flow using ANSYS Fluent®. The implementation of the boundary conditions is achieved by developing User Defined Functions (UDFs) by means of C++ routines. The complete first order velocity slip boundary condition, including the thermal creep effects due to the axial temperature gradient and the effect of the wall curvature, and the temperature jump boundary condition are applied. The developed simulation tool is used for the preliminary design of Knudsen micropumps consisting of a sequence of curved and straight channels.

  14. Enhanced heat sink with geometry induced wall-jet

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hossain, Md. Mahamudul, E-mail: sohel0991@gmail.com; Tikadar, Amitav; Bari, Fazlul

    Mini-channels embedded in solid matrix have already proven to be a very efficient way of electronic cooling. Traditional mini-channel heat sinks consist of single layer of parallel channels. Although mini-channel heat sink can achieve very high heat flux, its pumping requirement for circulating liquid through the channel increase very sharply as the flow velocity increases. The pumping requirements of the heat sink can be reduced by increasing its performance. In this paper a novel approach to increase the thermal performance of the mini-channel heat sink is proposed through geometry induced wall jet which is a passive technique. Geometric irregularities alongmore » the channel length causes abrupt pressure change between the channels which causes cross flow through the interconnections thus one channel faces suction and other channel jet action. This suction and jet action disrupts boundary layer causing enhanced heat transfer performance. A CFD model has been developed using commercially available software package FLUENT to evaluate the technique. A parametric study of the velocities and the effect of the position of the wall-jets have been performed. Significant reduction in thermal resistance has been observed for wall-jets, it is also observed that this reduction in thermal resistance is dependent on the position and shape of the wall jet.« less

  15. Design of underwater robot lines based on a hybrid automatic optimization strategy

    NASA Astrophysics Data System (ADS)

    Lyu, Wenjing; Luo, Weilin

    2014-09-01

    In this paper, a hybrid automatic optimization strategy is proposed for the design of underwater robot lines. Isight is introduced as an integration platform. The construction of this platform is based on the user programming and several commercial software including UG6.0, GAMBIT2.4.6 and FLUENT12.0. An intelligent parameter optimization method, the particle swarm optimization, is incorporated into the platform. To verify the strategy proposed, a simulation is conducted on the underwater robot model 5470, which originates from the DTRC SUBOFF project. With the automatic optimization platform, the minimal resistance is taken as the optimization goal; the wet surface area as the constraint condition; the length of the fore-body, maximum body radius and after-body's minimum radius as the design variables. With the CFD calculation, the RANS equations and the standard turbulence model are used for direct numerical simulation. By analyses of the simulation results, it is concluded that the platform is of high efficiency and feasibility. Through the platform, a variety of schemes for the design of the lines are generated and the optimal solution is achieved. The combination of the intelligent optimization algorithm and the numerical simulation ensures a global optimal solution and improves the efficiency of the searching solutions.

  16. CFD Modelling Applied to the Co-Combustion of Paper Sludge and Coal in a 130 t/h CFB Boiler

    NASA Astrophysics Data System (ADS)

    Yu, Z. S.; Ma, X. Q.; Lai, Z. Y.; Xiao, H. M.

    Three-dimensional mathematical model has been developed as a tool for co-combustion of paper sludge and coal in a 130 tJh Circulating Fluidized Bed (CFB) boiler. Mathematical methods had been used based on a commercial software FLUENT for combustion. The predicted results of CFB furnace show that the co-combustion of paper sludge/coal is initially intensively at the bottom of bed; the temperature reaches its maximum in the dense-phase zone, around l400K. It indicates that paper sludge spout into furnace from the recycle inlet can increase the furnace maximum temperature (l396.3K), area-weighted average temperature (l109.6K) and the furnace gas outlet area-weighted average temperature(996.8K).The mathematical modeling also predicts that 15 mass% paper sludge co-combustion is the highest temperature at the flue gas outlet, it is 1000.8K. Moreover, it is proved that mathematical models can serve as a tool for detailed analysis of co-combustion of paper sludge and coal processes in a circulating fluidized bed furnace when in view of its convenience. The results gained from numerical simulation show that paper sludge enter into furnace from the recycle inlet excelled than mixing with coal and at the underside of phase interface.

  17. CFD analysis of turboprop engine oil cooler duct for best rate of climb condition

    NASA Astrophysics Data System (ADS)

    Kalia, Saurabh; CA, Vinay; Hegde, Suresh M.

    2016-09-01

    Turboprop engines are widely used in commuter category airplanes. Aircraft Design bureaus routinely conduct the flight tests to confirm the performance of the system. The lubrication system of the engine is designed to provide a constant supply of clean lubrication oil to the engine bearings, the reduction gears, the torque-meter, the propeller and the accessory gearbox. The oil lubricates, cools and also conducts foreign material to the oil filter where it is removed from further circulation. Thus a means of cooling the engine oil must be provided and a suitable oil cooler (OC) and ducting system was selected and designed for this purpose. In this context, it is relevant to study and analyse behaviour of the engine oil cooler system before commencing actual flight tests. In this paper, the performance of the oil cooler duct with twin flush NACA inlet housed inside the nacelle has been studied for aircraft best rate of climb (ROC) condition using RANS based SST K-omega model by commercial software ANSYS Fluent 13.0. From the CFD analysis results, it is found that the mass flow rate captured and pressure drop across the oil cooler for the best ROC condition is meeting the oil cooler manufacturer requirements thus, the engine oil temperature is maintained within prescribed limits.

  18. Analysis of Wind Forces on Roof-Top Solar Panel

    NASA Astrophysics Data System (ADS)

    Panta, Yogendra; Kudav, Ganesh

    2011-03-01

    Structural loads on solar panels include forces due to high wind, gravity, thermal expansion, and earthquakes. International Building Code (IBC) and the American Society of Civil Engineers are two commonly used approaches in solar industries to address wind loads. Minimum Design Loads for Buildings and Other Structures (ASCE 7-02) can be used to calculate wind uplift loads on roof-mounted solar panels. The present study is primarily focused on 2D and 3D modeling with steady, and turbulent flow over an inclined solar panel on the flat based roof to predict the wind forces for designing wind management system. For the numerical simulation, 3-D incompressible flow with the standard k- ɛ was adopted and commercial CFD software ANSYS FLUENT was used. Results were then validated with wind tunnel experiments with a good agreement. Solar panels with various aspect ratios for various high wind speeds and angle of attacks were modeled and simulated in order to predict the wind loads in various scenarios. The present study concluded to reduce the strong wind uplift by designing a guide plate or a deflector before the panel. Acknowledgments to Northern States Metal Inc., OH (GK & YP) and School of Graduate Studies of YSU for RP & URC 2009-2010 (YP).

  19. 48 CFR 27.405-3 - Commercial computer software.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... software. 27.405-3 Section 27.405-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION... Commercial computer software. (a) When contracting other than from GSA's Multiple Award Schedule contracts for the acquisition of commercial computer software, no specific contract clause prescribed in this...

  20. 48 CFR 27.405-3 - Commercial computer software.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... software. 27.405-3 Section 27.405-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION... Commercial computer software. (a) When contracting other than from GSA's Multiple Award Schedule contracts for the acquisition of commercial computer software, no specific contract clause prescribed in this...

  1. 48 CFR 27.405-3 - Commercial computer software.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... software. 27.405-3 Section 27.405-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION... Commercial computer software. (a) When contracting other than from GSA's Multiple Award Schedule contracts for the acquisition of commercial computer software, no specific contract clause prescribed in this...

  2. 48 CFR 27.405-3 - Commercial computer software.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... software. 27.405-3 Section 27.405-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION... Commercial computer software. (a) When contracting other than from GSA's Multiple Award Schedule contracts for the acquisition of commercial computer software, no specific contract clause prescribed in this...

  3. 48 CFR 27.405-3 - Commercial computer software.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... software. 27.405-3 Section 27.405-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION... Commercial computer software. (a) When contracting other than from GSA's Multiple Award Schedule contracts for the acquisition of commercial computer software, no specific contract clause prescribed in this...

  4. 48 CFR 52.227-19 - Commercial Computer Software License.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Software License. 52.227-19 Section 52.227-19 Federal Acquisition Regulations System FEDERAL ACQUISITION... Clauses 52.227-19 Commercial Computer Software License. As prescribed in 27.409(g), insert the following clause: Commercial Computer Software License (DEC 2007) (a) Notwithstanding any contrary provisions...

  5. 48 CFR 52.227-19 - Commercial Computer Software License.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Software License. 52.227-19 Section 52.227-19 Federal Acquisition Regulations System FEDERAL ACQUISITION... Clauses 52.227-19 Commercial Computer Software License. As prescribed in 27.409(g), insert the following clause: Commercial Computer Software License (DEC 2007) (a) Notwithstanding any contrary provisions...

  6. 48 CFR 52.227-19 - Commercial Computer Software License.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Software License. 52.227-19 Section 52.227-19 Federal Acquisition Regulations System FEDERAL ACQUISITION... Clauses 52.227-19 Commercial Computer Software License. As prescribed in 27.409(g), insert the following clause: Commercial Computer Software License (DEC 2007) (a) Notwithstanding any contrary provisions...

  7. 48 CFR 52.227-19 - Commercial Computer Software License.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Software License. 52.227-19 Section 52.227-19 Federal Acquisition Regulations System FEDERAL ACQUISITION... Clauses 52.227-19 Commercial Computer Software License. As prescribed in 27.409(g), insert the following clause: Commercial Computer Software License (DEC 2007) (a) Notwithstanding any contrary provisions...

  8. 48 CFR 52.227-19 - Commercial Computer Software License.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Software License. 52.227-19 Section 52.227-19 Federal Acquisition Regulations System FEDERAL ACQUISITION... Clauses 52.227-19 Commercial Computer Software License. As prescribed in 27.409(g), insert the following clause: Commercial Computer Software License (DEC 2007) (a) Notwithstanding any contrary provisions...

  9. 48 CFR 227.7202-4 - Contract clause.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Software and Computer Software Documentation 227.7202-4 Contract clause. A specific contract clause governing the Government's rights in commercial computer software or commercial computer software..., release, perform, display, or disclose computer software or computer software documentation shall be...

  10. 48 CFR 227.7202-4 - Contract clause.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Software and Computer Software Documentation 227.7202-4 Contract clause. A specific contract clause governing the Government's rights in commercial computer software or commercial computer software..., release, perform, display, or disclose computer software or computer software documentation shall be...

  11. 48 CFR 227.7202-4 - Contract clause.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Software and Computer Software Documentation 227.7202-4 Contract clause. A specific contract clause governing the Government's rights in commercial computer software or commercial computer software..., release, perform, display, or disclose computer software or computer software documentation shall be...

  12. 48 CFR 227.7202-4 - Contract clause.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Software and Computer Software Documentation 227.7202-4 Contract clause. A specific contract clause governing the Government's rights in commercial computer software or commercial computer software..., release, perform, display, or disclose computer software or computer software documentation shall be...

  13. 48 CFR 227.7202-4 - Contract clause.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Software and Computer Software Documentation 227.7202-4 Contract clause. A specific contract clause governing the Government's rights in commercial computer software or commercial computer software..., release, perform, display, or disclose computer software or computer software documentation shall be...

  14. Educational Software Acquisition for Microcomputers.

    ERIC Educational Resources Information Center

    Erikson, Warren; Turban, Efraim

    1985-01-01

    Examination of issues involved in acquiring appropriate microcomputer software for higher education focuses on the following points: developing your own software; finding commercially available software; using published evaluations; pre-purchase testing; customizing and adapting commercial software; post-purchase testing; and software use. A…

  15. Research in Varying Burner Tilt Angle to Reduce Rear Pass Temperature in Coal Fired Boiler

    NASA Astrophysics Data System (ADS)

    Thrangaraju, Savithry K.; Munisamy, Kannan M.; Baskaran, Saravanan

    2017-04-01

    This research shows the investigation conducted on one of techniques that is used in Manjung 700 MW tangentially fired coal power plant. The investigation conducted in this research is finding out the right tilt angle for the burners in the boiler that causes an efficient temperature distribution and combustion gas flow pattern in the boiler especially at the rear pass section. The main outcome of the project is to determine the right tilt angle for the burner to create an efficient temperature distribution and combustion gas flow pattern that able to increase the efficiency of the boiler. The investigation is carried out by using Computational Fluid Dynamics method to obtain the results by varying the burner tilt angle. The boiler model is drawn by using designing software which is called Solid Works and Fluent from Computational Fluid Dynamics is used to conduct the analysis on the boiler model. The analysis is to imitate the real combustion process in the real Manjung 700 MW boiler. The expected results are to determine the right burner tilt angle with a computational fluid analysis by obtaining the temperature distribution and combustion gas flow pattern for each of the three angles set for the burner tilt angle in FLUENT software. Three burner tilt angles are selected which are burner tilt angle at (0°) as test case 1, burner tilt angle at (+10°) as test case 2 and burner tilt angle at (-10°) as test case 3. These entire three cases were run in CFD software and the results of temperature distribution and velocity vector were obtained to find out the changes on the three cases at the furnace and rear pass section of the boiler. The results are being compared in analysis part by plotting graphs to determine the right tilting angle that reduces the rear pass temperature.

  16. [CFD numerical simulation onto the gas-liquid two-phase flow behavior during vehicle refueling process].

    PubMed

    Chen, Jia-Qing; Zhang, Nan; Wang, Jin-Hui; Zhu, Ling; Shang, Chao

    2011-12-01

    With the gradual improvement of environmental regulations, more and more attentions are attracted to the vapor emissions during the process of vehicle refueling. Research onto the vehicle refueling process by means of numerical simulation has been executed abroad since 1990s, while as it has never been involved so far domestically. Through reasonable simplification about the physical system of "Nozzle + filler pipe + gasoline storage tank + vent pipe" for vehicle refueling, and by means of volume of fluid (VOF) model for gas-liquid two-phase flow and Re-Normalization Group kappa-epsilon turbulence flow model provided in commercial computational fluid dynamics (CFD) software Fluent, this paper determined the proper mesh discretization scheme and applied the proper boundary conditions based on the Gambit software, then established the reasonable numerical simulation model for the gas-liquid two-phase flow during the refueling process. Through discussing the influence of refueling velocity on the static pressure of vent space in gasoline tank, the back-flowing phenomenon has been revealed in this paper. It has been demonstrated that, the more the flow rate and the refueling velocity of refueling nozzle is, the higher the gross static pressure in the vent space of gasoline tank. In the meanwhile, the variation of static pressure in the vent space of gasoline tank can be categorized into three obvious stages. When the refueling flow rate becomes higher, the back-flowing phenomenon of liquid gasoline can sometimes be induced in the head section of filler pipe, thus making the gasoline nozzle pre-shut-off. Totally speaking, the theoretical work accomplished in this paper laid some solid foundation for self-researching and self-developing the technology and apparatus for the vehicle refueling and refueling emissions control domestically.

  17. Vibration analysis of large centrifugal pump rotors

    NASA Astrophysics Data System (ADS)

    Y Zhao, W.; Ge, J. G.; Ma, D.; Li, C. M.; Bao, S. B.

    2013-12-01

    Through the critical speed of centrifugal pumps, internal flow field and the force of the impeller, we analyze centrifugal pump vibration. Using finite element analysis software ANSYS to calculate the natural frequency of the rotor system and the critical speed; with the help of the Fluent software to simulate pump internal flow field, we conclude that speed increase will not cause intense vibration of the fluid in the pump. Using unsteady numerical simulation we discovered that in an impeller suffering transient radial force cyclical change periodically, as well as the frequency size determined by the product of the impeller speed and number of blades, resonance phenomena should make impeller to transient radial force frequency. If wanting to avoid pump resonance when it is running away, the transient radial force frequency should avoid the frequency range which can cause resonance.

  18. Communication between South Asian patients and GPs: comparative study using the Roter Interactional Analysis System

    PubMed Central

    Neal, Richard D; Ali, Nasreen; Atkin, Karl; Allgar, Victoria L; Ali, Shahid; Coleman, Tim

    2006-01-01

    Background The UK South Asian population has poorer health outcomes. Little is known about their process of care in general practice, or in particular the process of communication with GPs. Aim To compare the ways in which white and South Asian patients communicate with white GPs. Design of study Observational study of video-recorded consultations using the Roter Interactional Analysis System (RIAS). Setting West Yorkshire, UK. Method One hundred and eighty–three consultations with 11 GPs in West Yorkshire, UK were video-recorded and analysed. Results Main outcome measures were consultation length, verbal domination, 16 individual abridged RIAS categories, and three composite RIAS categories; with comparisons between white patients, South Asian patients fluent in English and South Asian patients non-fluent in English. South Asians fluent in English had the shortest consultations and South Asians non-fluent in English the longest consultations (one-way ANOVA F = 7.173, P = 0.001). There were no significant differences in verbal domination scores between the three groups. White patients had more affective (emotional) consultations than South Asian patients, and played a more active role in their consultations, as did their GPs. GPs spent less time giving information to South Asian patients who were not fluent in English and more time asking questions. GPs spent less time giving information to South Asian patients fluent in English compared with white patients. Conclusions These findings were expected between patients fluent and non-fluent in English but do demonstrate their nature. The differences between white patients and South Asian patients fluent in English warrant further explanation. How much of this was due to systematic differences in behaviour by the GPs, or was in response to patients' differing needs and expectations is unknown. These differences may contribute to differences in health outcomes. PMID:17132355

  19. What’s the Story? The Tale of Reading Fluency Told at Speed

    PubMed Central

    Benjamin, Christopher F. A.; Gaab, Nadine

    2012-01-01

    Fluent readers process written text rapidly and accurately, and comprehend what they read. Historically, reading fluency has been modeled as the product of discrete skills such as single word decoding. More recent conceptualizations emphasize that fluent reading is the product of competency in, and the coordination of, multiple cognitive sub-skills (a multi-componential view). In this study, we examined how the pattern of activation in core reading regions changes as the ability to read fluently is manipulated through reading speed. We evaluated 13 right-handed adults with a novel fMRI task assessing fluent sentence reading and lower-order letter reading at each participant’s normal fluent reading speed, as well as constrained (slowed) and accelerated reading speeds. Comparing fluent reading conditions with rest revealed regions including bilateral occipito-fusiform, left middle temporal, and inferior frontal gyral clusters across reading speeds. The selectivity of these regions’ responses to fluent sentence reading was shown by comparison with the letter reading task. Region of interest analyses showed that at constrained and accelerated speeds these regions responded significantly more to fluent sentence reading. Critically, as reading speed increased, activation increased in a single reading-related region: occipital/fusiform cortex (left > right). These results demonstrate that while brain regions engaged in reading respond selectively during fluent reading, these regions respond differently as the ability to read fluently is manipulated. Implications for our understanding of reading fluency, reading development, and reading disorders are discussed. PMID:21954000

  20. A three-dimensional numerical simulation of cell behavior in a flow chamber based on fluid-solid interaction.

    PubMed

    Bai, Long; Cui, Yuhong; Zhang, Yixia; Zhao, Na

    2014-01-01

    The mechanical behavior of blood cells in the vessels has a close relationship with the physical characteristics of the blood and the cells. In this paper, a numerical simulation method was proposed to understand a single-blood cell's behavior in the vessels based on fluid-solid interaction method, which was conducted under adaptive time step and fixed time step, respectively. The main programme was C++ codes, which called FLUENT and ANSYS software, and UDF and APDL acted as a messenger to connect FLUENT and ANSYS for exchanging data. The computing results show: (1) the blood cell moved towards the bottom of the flow chamber in the beginning due to the influence of gravity, then it began to jump up when reached a certain height rather than touching the bottom. It could move downwards again after jump up, the blood cell could keep this way of moving like dancing continuously in the vessels; (2) the blood cell was rolling and deforming all the time; the rotation had oscillatory changes and the deformation became conspicuously when the blood cell was dancing. This new simulation method and results can be widely used in the researches of cytology, blood, cells, etc.

  1. A modified Brownian force for ultrafine particle penetration through building crack modeling

    NASA Astrophysics Data System (ADS)

    Chen, Chen; Zhao, Bin

    2017-12-01

    Combustion processes related to industry, traffic, agriculture, and waste treatment and disposal increase the amount of outdoor ultrafine particles (UFPs), which have adverse effects on human health. Given that people spend the majority of their time indoors, it is critical to understand the penetration of outdoor UFPs through building cracks in order to estimate human exposure to outdoor-originated UFPs. Lagrangian tracking is an efficient approach for modeling particle penetration. However, the Brownian motion for Lagrangian tracking in ANSYS Fluent®, a widely used software for particle dispersion modeling, is not able to model UFP dispersion accurately. In this study, we modified the Brownian force by rewriting the Brownian diffusion coefficient and particle integration time step with a user-defined function in ANSYS Fluent® to model particle penetration through building cracks. The results obtained using the modified model agree much better with the experimental results, with the averaged relative error less than 14% for the smooth crack cases and 21% for the rough crack case. We expect the modified Brownian force model proposed herein to be applied for UFP dispersion modeling in more indoor air quality studies.

  2. Numerical Simulation in a Supercirtical CFB Boiler

    NASA Astrophysics Data System (ADS)

    Zhang, Yanjun; Gaol, Xiang; Luo, Zhongyang; Jiang, Xiaoguo

    The dimension of the hot circulation loop of the supercritical CFB boiler is large, and there are many unknowns and challenges that should be identified and resolved during the development. In order to realize a reasonable and reliable design of the hot circulation loop, numerical simulation of gas-solid flow in a supercritical CFB boiler was conducted by using FLUENT software. The working condition of hot circulation loop flow field, gas-solid flow affected by three unsymmetrical cyclones, air distribution and pressure drop in furnace were analyzed. The simulation results showed that the general arrangement of the 600MWe supercritical CFB boiler is reasonable.

  3. Analysis of dangerous area of single berth oil tanker operations based on CFD

    NASA Astrophysics Data System (ADS)

    Shi, Lina; Zhu, Faxin; Lu, Jinshu; Wu, Wenfeng; Zhang, Min; Zheng, Hailin

    2018-04-01

    Based on the single process in the liquid cargo tanker berths in the state as the research object, we analyzed the single berth oil tanker in the process of VOCs diffusion theory, built network model of VOCs diffusion with Gambit preprocessor, set up the simulation boundary conditions and simulated the five detection point sources in specific factors under the influence of VOCs concentration change with time by using Fluent software. We analyzed the dangerous area of single berth oil tanker operations through the diffusion of VOCs, so as to ensure the safe operation of oil tanker.

  4. Fluent aphasia in children: definition and natural history.

    PubMed

    Klein, S K; Masur, D; Farber, K; Shinnar, S; Rapin, I

    1992-01-01

    We compared the course of a preschool child we followed for 4 years with published reports of 24 children with fluent aphasia. Our patient spoke fluently within 3 weeks of the injury. She was severely anomic and made many semantic paraphasic errors. Unlike other children with fluent aphasia, her prosody of speech was impaired initially, and her spontaneous language was dominated by stock phrases. Residual deficits include chronic impairment of auditory comprehension, repetition, and word retrieval. She has more disfluencies in spontaneous speech 4 years after her head injury than acutely. School achievement in reading and mathematics remains below age level. Attention to the timing of recovery of fluent speech and to the characteristics of receptive and expressive language over time will permit more accurate description of fluent aphasia in childhood.

  5. Comparison of 3D reconstruction of mandible for pre-operative planning using commercial and open-source software

    NASA Astrophysics Data System (ADS)

    Abdullah, Johari Yap; Omar, Marzuki; Pritam, Helmi Mohd Hadi; Husein, Adam; Rajion, Zainul Ahmad

    2016-12-01

    3D printing of mandible is important for pre-operative planning, diagnostic purposes, as well as for education and training. Currently, the processing of CT data is routinely performed with commercial software which increases the cost of operation and patient management for a small clinical setting. Usage of open-source software as an alternative to commercial software for 3D reconstruction of the mandible from CT data is scarce. The aim of this study is to compare two methods of 3D reconstruction of the mandible using commercial Materialise Mimics software and open-source Medical Imaging Interaction Toolkit (MITK) software. Head CT images with a slice thickness of 1 mm and a matrix of 512x512 pixels each were retrieved from the server located at the Radiology Department of Hospital Universiti Sains Malaysia. The CT data were analysed and the 3D models of mandible were reconstructed using both commercial Materialise Mimics and open-source MITK software. Both virtual 3D models were saved in STL format and exported to 3matic and MeshLab software for morphometric and image analyses. Both models were compared using Wilcoxon Signed Rank Test and Hausdorff Distance. No significant differences were obtained between the 3D models of the mandible produced using Mimics and MITK software. The 3D model of the mandible produced using MITK open-source software is comparable to the commercial MIMICS software. Therefore, open-source software could be used in clinical setting for pre-operative planning to minimise the operational cost.

  6. 78 FR 45196 - Federal Acquisition Regulation; Information Collection; Rights in Data and Copyrights

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-26

    .... (5) FAR 52.227-19, Commercial Computer Software License. This clause is used in contracts and... standard commercial license. The contractor is responsible for affixing a notice on any commercial software..., Representation of Limited Rights Data and Restricted Computer Software. This clauses is included in solicitations...

  7. 48 CFR 227.7202-1 - Policy.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... OF DEFENSE GENERAL CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202-1 Policy. (a) Commercial computer software or commercial computer software documentation shall be acquired under the licenses customarily provided to the public...

  8. 48 CFR 227.7202-1 - Policy.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... OF DEFENSE GENERAL CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202-1 Policy. (a) Commercial computer software or commercial computer software documentation shall be acquired under the licenses customarily provided to the public...

  9. 48 CFR 227.7202-1 - Policy.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... OF DEFENSE GENERAL CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202-1 Policy. (a) Commercial computer software or commercial computer software documentation shall be acquired under the licenses customarily provided to the public...

  10. 48 CFR 227.7202-1 - Policy.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... OF DEFENSE GENERAL CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202-1 Policy. (a) Commercial computer software or commercial computer software documentation shall be acquired under the licenses customarily provided to the public...

  11. 48 CFR 227.7202-1 - Policy.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... OF DEFENSE GENERAL CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Rights in Computer Software and Computer Software Documentation 227.7202-1 Policy. (a) Commercial computer software or commercial computer software documentation shall be acquired under the licenses customarily provided to the public...

  12. Listeners' identification and discrimination of digitally manipulated sounds as prolongations.

    PubMed

    Kawai, Norimune; Healey, E Charles; Carrell, Thomas D

    2007-08-01

    The present study had two main purposes. One was to examine if listeners perceive gradually increasing durations of a voiceless fricative categorically ("fluent" versus "stuttered") or continuously (gradient perception from fluent to stuttered). The second purpose was to investigate whether there are gender differences in how listeners perceive various duration of sounds as "prolongations." Forty-four listeners were instructed to rate the duration of the // in the word "shape" produced by a normally fluent speaker. The target word was embedded in the middle of an experimental phrase and the initial // sound was digitally manipulated to create a range of fluent to stuttered sounds. This was accomplished by creating 20 ms stepwise increments for sounds ranging from 120 to 500 ms in duration. Listeners were instructed to give a rating of 1 for a fluent word and a rating of 100 for a stuttered word. The results showed listeners perceived the range of sounds continuously. Also, there was a significant gender difference in that males rated fluent sounds higher than females but female listeners rated stuttered sounds higher than males. The implications of these results are discussed.

  13. Reduced order model based on principal component analysis for process simulation and optimization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lang, Y.; Malacina, A.; Biegler, L.

    2009-01-01

    It is well-known that distributed parameter computational fluid dynamics (CFD) models provide more accurate results than conventional, lumped-parameter unit operation models used in process simulation. Consequently, the use of CFD models in process/equipment co-simulation offers the potential to optimize overall plant performance with respect to complex thermal and fluid flow phenomena. Because solving CFD models is time-consuming compared to the overall process simulation, we consider the development of fast reduced order models (ROMs) based on CFD results to closely approximate the high-fidelity equipment models in the co-simulation. By considering process equipment items with complicated geometries and detailed thermodynamic property models,more » this study proposes a strategy to develop ROMs based on principal component analysis (PCA). Taking advantage of commercial process simulation and CFD software (for example, Aspen Plus and FLUENT), we are able to develop systematic CFD-based ROMs for equipment models in an efficient manner. In particular, we show that the validity of the ROM is more robust within well-sampled input domain and the CPU time is significantly reduced. Typically, it takes at most several CPU seconds to evaluate the ROM compared to several CPU hours or more to solve the CFD model. Two case studies, involving two power plant equipment examples, are described and demonstrate the benefits of using our proposed ROM methodology for process simulation and optimization.« less

  14. Combined Effect of Surface Roughness and Wake Splitter Plate on the Aerodynamic Characteristics of a Circular Cylinder

    NASA Astrophysics Data System (ADS)

    Saisanthosh, Iyer; Arunkumar, K.; Ajithkumar, R.; Srikrishnan, A. R.

    2017-09-01

    This paper is focussed on numerical investigation of flow around a stationary circular cylinder (diameter, D) with selectively applied surface roughness (roughness strips with thickness ‘k’) in the presence of a wake splitter plate (length, L). The plate leading edge is at a distance of ‘G’ from the cylinder base. For this study, the commercial software ANSYS Fluent is used. Fluid considered is water. Study was conducted the following cases (a) plain cylinder (b) cylinder with surface roughness (without splitter plate) (c) Cylinder with splitter plate (without surface roughness) and (d) cylinder with both roughness and splitter plate employed. The study Reynolds number (based on D) is 17,000 and k/δ = 1.25 (in all cases). Results indicate that, for cylinder with splitter plate (no roughness), lift coefficient gradually drops till G/D=1.5 further to which it sharply increases. Whereas, drag coefficient and Strouhal number undergoes slight reduction till G/D=1.0 and thereafter, gradually increase. Circumferential location of strip (α) does not influence the aerodynamic parameters significantly. With roughness alone, drag is magnified by about 1.5 times and lift, by about 2.7 times that of the respective values of the smooth cylinder. With splitter plate, for roughness applied at all ‘α’ values, drag and lift undergoes substantial reduction with the lowest value attained at G/D=1.0.

  15. Study of the filtration performance of a plain wave fabric filter using response surface methodology.

    PubMed

    Qian, Fuping; Wang, Haigang

    2010-04-15

    The gas-solid two-phase flows in the plain wave fabric filter were simulated by computational fluid dynamics (CFD) technology, and the warps and wefts of the fabric filter were made of filaments with different dimensions. The numerical solutions were carried out using commercial computational fluid dynamics (CFD) code Fluent 6.1. The filtration performances of the plain wave fabric filter with different geometry parameters and operating condition, including the horizontal distance, the vertical distance and the face velocity were calculated. The effects of geometry parameters and operating condition on filtration efficiency and pressure drop were studied using response surface methodology (RSM) by means of the statistical software (Minitab V14), and two second-order polynomial models were obtained with regard to the effect of the three factors as stated above. Moreover, the models were modified by dismissing the insignificant terms. The results show that the horizontal distance, vertical distance and the face velocity all play an important role in influencing the filtration efficiency and pressure drop of the plane wave fabric filters. The horizontal distance of 3.8 times the fiber diameter, the vertical distance of 4.0 times the fiber diameter and Reynolds number of 0.98 are found to be the optimal conditions to achieve the highest filtration efficiency at the same face velocity, while maintaining an acceptable pressure drop. 2009 Elsevier B.V. All rights reserved.

  16. Numerical study of the effects of lamp configuration and reactor wall roughness in an open channel water disinfection UV reactor.

    PubMed

    Sultan, Tipu

    2016-07-01

    This article describes the assessment of a numerical procedure used to determine the UV lamp configuration and surface roughness effects on an open channel water disinfection UV reactor. The performance of the open channel water disinfection UV reactor was numerically analyzed on the basis of the performance indictor reduction equivalent dose (RED). The RED values were calculated as a function of the Reynolds number to monitor the performance. The flow through the open channel UV reactor was modelled using a k-ε model with scalable wall function, a discrete ordinate (DO) model for fluence rate calculation, a volume of fluid (VOF) model to locate the unknown free surface, a discrete phase model (DPM) to track the pathogen transport, and a modified law of the wall to incorporate the reactor wall roughness effects. The performance analysis was carried out using commercial CFD software (ANSYS Fluent 15.0). Four case studies were analyzed based on open channel UV reactor type (horizontal and vertical) and lamp configuration (parallel and staggered). The results show that lamp configuration can play an important role in the performance of an open channel water disinfection UV reactor. The effects of the reactor wall roughness were Reynolds number dependent. The proposed methodology is useful for performance optimization of an open channel water disinfection UV reactor. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Lactation in the Human Breast From a Fluid Dynamics Point of View.

    PubMed

    Negin Mortazavi, S; Geddes, Donna; Hassanipour, Fatemeh

    2017-01-01

    This study is a collaborative effort among lactation specialists and fluid dynamic engineers. The paper presents clinical results for suckling pressure pattern in lactating human breast as well as a 3D computational fluid dynamics (CFD) modeling of milk flow using these clinical inputs. The investigation starts with a careful, statistically representative measurement of suckling vacuum pressure, milk flow rate, and milk intake in a group of infants. The results from clinical data show that suckling action does not occur with constant suckling rate but changes in a rhythmic manner for infants. These pressure profiles are then used as the boundary condition for the CFD study using commercial ansys fluent software. For the geometric model of the ductal system of the human breast, this work takes advantage of a recent advance in the development of a validated phantom that has been produced as a ground truth for the imaging applications for the breast. The geometric model is introduced into CFD simulations with the aforementioned boundary conditions. The results for milk intake from the CFD simulation and clinical data were compared and cross validated. Also, the variation of milk intake versus suckling pressure are presented and analyzed. Both the clinical and CFD simulation show that the maximum milk flow rate is not related to the largest vacuum pressure or longest feeding duration indicating other factors influence the milk intake by infants.

  18. Study on installation of the submersible mixer

    NASA Astrophysics Data System (ADS)

    Tian, F.; Shi, W. D.; He, X. H.; Jiang, H.; Xu, Y. H.

    2013-12-01

    Study on installation of the submersible mixer for sewage treatment has been limited. In this article, large-scale computational fluid dynamics software FLUENT6.3 was adopted. ICEM software was used to build an unstructured grid of sewage treatment pool. After that, the sewage treatment pool was numerically simulated by dynamic coordinate system technology and RNG k-ε turbulent model and PIOS algorithm. Agitation pools on four different installation location cases were simulated respectively, and the external characteristic of the submersible mixer and the velocity cloud of the axial section were respectively comparatively analyzed. The best stirring effect can be reached by the installation location of case C, which is near the bottom of the pool 600 mm and blade distance the bottom at least for 200 mm wide and wide edge and narrow edge distance by 4:3. The conclusion can guide the engineering practice.

  19. Molded underfill (MUF) encapsulation for flip-chip package: A numerical investigation

    NASA Astrophysics Data System (ADS)

    Azmi, M. A.; Abdullah, M. K.; Abdullah, M. Z.; Ariff, Z. M.; Saad, Abdullah Aziz; Hamid, M. F.; Ismail, M. A.

    2017-07-01

    This paper presents the numerical simulation of epoxy molding compound (EMC) filling in multi flip-chip packages during encapsulation process. The empty and a group flip chip packages were considered in the mold cavity in order to study the flow profile of the EMC. SOLIDWORKS software was used for three-dimensional modeling and it was incorporated into fluid analysis software namely as ANSYS FLUENT. The volume of fluid (VOF) technique was used for capturing the flow front profiles and Power Law model was applied for its rheology model. The numerical result are compared and discussed with previous experimental and it was shown a good conformity for model validation. The prediction of flow front was observed and analyzed at different filling time. The possibility and visual of void formation in the package is captured and the number of flip-chip is one factor that contributed to the void formation.

  20. 48 CFR 212.212 - Computer software.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 3 2013-10-01 2013-10-01 false Computer software. 212.212... Acquisition of Commercial Items 212.212 Computer software. (1) Departments and agencies shall identify and... technology development), opportunities for the use of commercial computer software and other non...

  1. 48 CFR 212.212 - Computer software.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 3 2011-10-01 2011-10-01 false Computer software. 212.212... Acquisition of Commercial Items 212.212 Computer software. (1) Departments and agencies shall identify and... technology development), opportunities for the use of commercial computer software and other non...

  2. 48 CFR 212.212 - Computer software.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 3 2012-10-01 2012-10-01 false Computer software. 212.212... Acquisition of Commercial Items 212.212 Computer software. (1) Departments and agencies shall identify and... technology development), opportunities for the use of commercial computer software and other non...

  3. 48 CFR 212.212 - Computer software.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Computer software. 212.212... Acquisition of Commercial Items 212.212 Computer software. (1) Departments and agencies shall identify and... technology development), opportunities for the use of commercial computer software and other non...

  4. 48 CFR 212.212 - Computer software.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Computer software. 212.212... Acquisition of Commercial Items 212.212 Computer software. (1) Departments and agencies shall identify and... technology development), opportunities for the use of commercial computer software and other non...

  5. Computer modeling of a hot filament diamond deposition reactor

    NASA Technical Reports Server (NTRS)

    Kuczmarski, Maria A.; Washlock, Paul A.; Angus, John C.

    1991-01-01

    A commercial fluid mechanics program, FLUENT, has been applied to the modeling of a hot-filament diamond deposition reactor. Streamlines and contours of constant temperature and species concentrations are obtained for practical reactor geometries and conditions. The modeling is presently restricted to two-dimensional simulations and to a chemical mechanism of ten independent homogeneous and surface reactions. Comparisons are made between predicted power consumption, substrate temperature, and concentrations of atomic hydrogen and methyl-radical with values taken from the literature. The results to date indicate that the modeling can aid in the rational design and analysis of practical reactor configurations.

  6. Running ANSYS Fluent on the WinHPC System | High-Performance Computing |

    Science.gov Websites

    . If you don't have one, see WinHPC system user basics. Check License Use Status Start > All Jason Lustbader. Run Using Fluent Launcher Start Fluent launcher by opening: Start > All Programs > . Available node groups can be found from HPC Job Manager. Start > All Programs > Microsoft HPC Pack

  7. How Do Fluent and Poor Readers' Endurance Differ in Reading?

    ERIC Educational Resources Information Center

    Bastug, Muhammet; Keskin, Hasan Kagan; Akyol, Mustafa

    2017-01-01

    It was observed in this research how endurance status of fluent readers and poor readers changed as the text became longer. 40 students of the primary school 4th-grade, 20 were fluent readers and other 20 were poor readers, participated in the research. A narrative text was utilised in the data collection process. Students' oral readings were…

  8. Experience with turbulence interaction and turbulence-chemistry models at Fluent Inc.

    NASA Technical Reports Server (NTRS)

    Choudhury, D.; Kim, S. E.; Tselepidakis, D. P.; Missaghi, M.

    1995-01-01

    This viewgraph presentation discusses (1) turbulence modeling: challenges in turbulence modeling, desirable attributes of turbulence models, turbulence models in FLUENT, and examples using FLUENT; and (2) combustion modeling: turbulence-chemistry interaction and FLUENT equilibrium model. As of now, three turbulence models are provided: the conventional k-epsilon model, the renormalization group model, and the Reynolds-stress model. The renormalization group k-epsilon model has broadened the range of applicability of two-equation turbulence models. The Reynolds-stress model has proved useful for strongly anisotropic flows such as those encountered in cyclones, swirlers, and combustors. Issues remain, such as near-wall closure, with all classes of models.

  9. The Vibration Analysis of Tube Bundles Induced by Fluid Elastic Excitation in Shell Side of Heat Exchanger

    NASA Astrophysics Data System (ADS)

    Bao, Minle; Wang, Lu; Li, Wenyao; Gao, Tianze

    2017-09-01

    Fluid elastic excitation in shell side of heat exchanger was deduced theoretically in this paper. Model foundation was completed by using Pro / Engineer software. The finite element model was constructed and imported into the FLUENT module. The flow field simulation adopted the dynamic mesh model, RNG k-ε model and no-slip boundary conditions. Analysing different positions vibration of tube bundles by selecting three regions in shell side of heat exchanger. The results show that heat exchanger tube bundles at the inlet of the shell side are more likely to be failure due to fluid induced vibration.

  10. Financial Planning in Transit : Use of Commercially Available Microcomputer Software

    DOT National Transportation Integrated Search

    1983-11-01

    This report addresses the potential of using commercially available microcomputer software for transit financial planning activities. Discussions with transit operators identified the need for inexpensive, easy to use software for ridership and fare ...

  11. The Development of Reading and Spelling Abilities in the First 3 Years of Learning Arabic

    ERIC Educational Resources Information Center

    Mohamed, Wessam; Elbert, Thomas; Landerl, Karin

    2011-01-01

    In a cross-sectional study, we investigated the development of fluent reading and spelling in the first 3 years of learning Arabic. The goals of our study were to: (1) validate suitable measures for fluent reading and spelling in the first 3 years of learning Arabic; (2) trace the developmental course of the relationship between fluent reading and…

  12. Numerical simulation of blast wave propagation in vicinity of standalone prism on flat plate

    NASA Astrophysics Data System (ADS)

    Valger, Svetlana; Fedorova, Natalya; Fedorov, Alexander

    2018-03-01

    In the paper, numerical simulation of shock wave propagation in the vicinity of a standalone prism and a prism with a cavity in front of it was carried out. The modeling was based on the solution of 3D Euler equations and Fluent software was used as a main computational tool. The algorithm for local dynamic mesh adaptation to high gradients of pressure was applied. The initial stage of the explosion of condensed explosive was described with the help of "Compressed balloon method". The research allowed describing the characteristic stages of the blast in a semi-closed space, the structure of secondary shock waves and their interaction with obstacles. The numerical approach in Fluent based on combining inviscid gas dynamics methods and "Compressed balloon method" was compared with the method which had been used by the authors earlier with the help of AUTODYN and which is based on the use of the hydrodynamic model of a material to describe state of detonation products. For the problem of shock wave propagation in the vicinity of standalone prism the comparison of the simulation results obtained using both the methods with the experimental data was performed on the dependence of static pressure and effective momentum on time for the characteristic points located on prism walls.

  13. New approach to reducing water consumption in commercial kitchen hood

    NASA Astrophysics Data System (ADS)

    Asmuin, N.; Pairan, M. R.

    2017-09-01

    Water mist sprays are used in wide range of application. However it is depend to the spray characteristic to suit the particular application. The modern commercial kitchen hood ventilation system was adopted with the water mist nozzle technology as an additional tool to increase the filtration efficiency. However, low level of filtration effectiveness and high water consumption were the major problems among the Commercial Kitchen Ventilation expert. Therefore, this study aims to develop a new mist spray technology to replacing the conventional KSJB nozzle (KSJB is a nozzle’s name). At the same time, an appropriate recommended location to install the nozzle in kitchen hood system was suggested. An extensive simulation works were carried out to observe the spray characteristics, ANSYS (FLUENT) was used for simulation wise. In the case of nozzle studies, nozzles were tested at 1 bar pressure of water and air. In comparison with conventional nozzles configuration, this new approach suggested nozzle configuration was reduce up to 50% of water consumption, which by adopted 3 numbers of nozzles instead of 6 numbers of nozzles in the commercial kitchen hood system. Therefore, this nozzle will be used in industry for their benefits of water consumption, filtration efficiency and reduced the safety limitations.

  14. Female Autism Phenotypes Investigated at Different Levels of Language and Developmental Abilities.

    PubMed

    Howe, Yamini J; O'Rourke, Julia A; Yatchmink, Yvette; Viscidi, Emma W; Jones, Richard N; Morrow, Eric M

    2015-11-01

    This study investigated the differences in clinical symptoms between females and males with autism spectrum disorder (ASD) across three verbal ability groups (nonverbal, phrase and fluent speech), based on which Autism Diagnostic Observation Schedule module was administered to 5723 individuals in four research datasets. In the Simons Simplex Collection and Autism Treatment Network, females with ASD and phrase or fluent speech had lower cognitive, adaptive, and social abilities than males. In the Autism Genetics Resource Exchange and the Autism Consortium, females with phrase or fluent speech had similar or better adaptive and social abilities than males. Females who were nonverbal had similar cognitive, adaptive, and social abilities as males. Population-based longitudinal studies of verbally fluent females with ASD are needed.

  15. Fault Tree Analysis Application for Safety and Reliability

    NASA Technical Reports Server (NTRS)

    Wallace, Dolores R.

    2003-01-01

    Many commercial software tools exist for fault tree analysis (FTA), an accepted method for mitigating risk in systems. The method embedded in the tools identifies a root as use in system components, but when software is identified as a root cause, it does not build trees into the software component. No commercial software tools have been built specifically for development and analysis of software fault trees. Research indicates that the methods of FTA could be applied to software, but the method is not practical without automated tool support. With appropriate automated tool support, software fault tree analysis (SFTA) may be a practical technique for identifying the underlying cause of software faults that may lead to critical system failures. We strive to demonstrate that existing commercial tools for FTA can be adapted for use with SFTA, and that applied to a safety-critical system, SFTA can be used to identify serious potential problems long before integrator and system testing.

  16. Fostering successful scientific software communities

    NASA Astrophysics Data System (ADS)

    Bangerth, W.; Heister, T.; Hwang, L.; Kellogg, L. H.

    2016-12-01

    Developing sustainable open source software packages for the sciences appears at first to be primarily a technical challenge: How can one create stable and robust algorithms, appropriate software designs, sufficient documentation, quality assurance strategies such as continuous integration and test suites, or backward compatibility approaches that yield high-quality software usable not only by the authors, but also the broader community of scientists? However, our experience from almost two decades of leading the development of the deal.II software library (http://www.dealii.org, a widely-used finite element package) and the ASPECT code (http://aspect.dealii.org, used to simulate convection in the Earth's mantle) has taught us that technical aspects are not the most difficult ones in scientific open source software. Rather, it is the social challenge of building and maintaining a community of users and developers interested in answering questions on user forums, contributing code, and jointly finding solutions to common technical and non-technical challenges. These problems are posed in an environment where project leaders typically have no resources to reward the majority of contributors, where very few people are specifically paid for the work they do on the project, and with frequent turnover of contributors as project members rotate into and out of jobs. In particular, much software work is done by graduate students who may become fluent enough in a software only a year or two before they leave academia. We will discuss strategies we have found do and do not work in maintaining and growing communities around the scientific software projects we lead. Specifically, we will discuss the management style necessary to keep contributors engaged, ways to give credit where credit is due, and structuring documentation to decrease reliance on forums and thereby allow user communities to grow without straining those who answer questions.

  17. Development of Flow over Blunt-Nosed Slender Bodies at Transonic Mach Numbers

    NASA Astrophysics Data System (ADS)

    Yanamashetti, Gireesh; Suryanarayana, G. K.; Mukherjee, Rinku

    2017-04-01

    Comparisons of the development of flow over a cylinder with a 20° cone nose and a cylinder with an ogive nose, which represent typical heat-shield configurations are studied using CFD and experiments at transonic Mach numbers. The Cp plots are studied to locate expansion or separation. Experiments are carried out at M = 0.8, 0.9, 0.95 and 1.1 and Re ≈ 2.45 × 106. Computations are carried out using the commercial package, FLUENT 6.3. Inadequate spatial resolution of pressure ports in experiments as well as limitations of the CFD tool result in some differences in experimental and CFD results.

  18. 48 CFR 1852.227-86 - Commercial computer software-Licensing.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... software-Licensing. 1852.227-86 Section 1852.227-86 Federal Acquisition Regulations System NATIONAL... Provisions and Clauses 1852.227-86 Commercial computer software—Licensing. As prescribed in 1827.409-70, insert the following clause: Commercial Computer Software—Licensing (DEC 1987) (a) Any delivered...

  19. 48 CFR 1852.227-86 - Commercial computer software-Licensing.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... software-Licensing. 1852.227-86 Section 1852.227-86 Federal Acquisition Regulations System NATIONAL... Provisions and Clauses 1852.227-86 Commercial computer software—Licensing. As prescribed in 1827.409-70, insert the following clause: Commercial Computer Software—Licensing (DEC 1987) (a) Any delivered...

  20. 48 CFR 1852.227-86 - Commercial computer software-Licensing.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... software-Licensing. 1852.227-86 Section 1852.227-86 Federal Acquisition Regulations System NATIONAL... Provisions and Clauses 1852.227-86 Commercial computer software—Licensing. As prescribed in 1827.409-70, insert the following clause: Commercial Computer Software—Licensing (DEC 1987) (a) Any delivered...

  1. 48 CFR 1852.227-86 - Commercial computer software-Licensing.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... software-Licensing. 1852.227-86 Section 1852.227-86 Federal Acquisition Regulations System NATIONAL... Provisions and Clauses 1852.227-86 Commercial computer software—Licensing. As prescribed in 1827.409-70, insert the following clause: Commercial Computer Software—Licensing (DEC 1987) (a) Any delivered...

  2. 48 CFR 1852.227-86 - Commercial computer software-Licensing.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... software-Licensing. 1852.227-86 Section 1852.227-86 Federal Acquisition Regulations System NATIONAL... Provisions and Clauses 1852.227-86 Commercial computer software—Licensing. As prescribed in 1827.409-70, insert the following clause: Commercial Computer Software—Licensing (DEC 1987) (a) Any delivered...

  3. 48 CFR 1852.227-19 - Commercial computer software-Restricted rights.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... software-Restricted rights. 1852.227-19 Section 1852.227-19 Federal Acquisition Regulations System NATIONAL... Provisions and Clauses 1852.227-19 Commercial computer software—Restricted rights. (a) As prescribed in 1827... regarding any computer software delivered under this contract/purchase order, the NASA Contracting Officer...

  4. 48 CFR 1852.227-19 - Commercial computer software-Restricted rights.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... software-Restricted rights. 1852.227-19 Section 1852.227-19 Federal Acquisition Regulations System NATIONAL... Provisions and Clauses 1852.227-19 Commercial computer software—Restricted rights. (a) As prescribed in 1827... regarding any computer software delivered under this contract/purchase order, the NASA Contracting Officer...

  5. 48 CFR 1852.227-19 - Commercial computer software-Restricted rights.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... software-Restricted rights. 1852.227-19 Section 1852.227-19 Federal Acquisition Regulations System NATIONAL... Provisions and Clauses 1852.227-19 Commercial computer software—Restricted rights. (a) As prescribed in 1827... regarding any computer software delivered under this contract/purchase order, the NASA Contracting Officer...

  6. 48 CFR 1852.227-19 - Commercial computer software-Restricted rights.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... software-Restricted rights. 1852.227-19 Section 1852.227-19 Federal Acquisition Regulations System NATIONAL... Provisions and Clauses 1852.227-19 Commercial computer software—Restricted rights. (a) As prescribed in 1827... regarding any computer software delivered under this contract/purchase order, the NASA Contracting Officer...

  7. 48 CFR 1852.227-19 - Commercial computer software-Restricted rights.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... software-Restricted rights. 1852.227-19 Section 1852.227-19 Federal Acquisition Regulations System NATIONAL... Provisions and Clauses 1852.227-19 Commercial computer software—Restricted rights. (a) As prescribed in 1827... regarding any computer software delivered under this contract/purchase order, the NASA Contracting Officer...

  8. Aerodynamic Simulation Analysis of Unmanned Airborne Electronic Bomb

    NASA Astrophysics Data System (ADS)

    Yang, Jiaoying; Guo, Yachao

    2017-10-01

    For microelectronic bombs for UAVs, on the basis of the use of rotors to lift the insurance on the basis of ammunition, increased tail to increase stability. The aerodynamic simulation of the outer structure of the ammunition was carried out by FLUENT software. The resistance coefficient, the lift coefficient and the pitch moment coefficient under different angle of attack and Mach number were obtained, and the aerodynamic characteristics of the electronic bomb were studied. The pressure line diagram and the velocity line diagram of the flow around the bomb are further analyzed, and the rationality of the external structure is verified, which provides a reference for the subsequent design of the electronic bomb.

  9. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Khan, Yasin; Khare, Vaibhav Rai; Mathur, Jyotirmay

    The paper describes a parametric study developed to estimate the energy savings potential of a radiant cooling system installed in a commercial building in India. The study is based on numerical modeling of a radiant cooling system installed in an Information Technology (IT) office building sited in the composite climate of Hyderabad. To evaluate thermal performance and energy consumption, simulations were carried out using the ANSYS FLUENT and EnergyPlus softwares, respectively. The building model was calibrated using the measured data for the installed radiant system. Then this calibrated model was used to simulate the energy consumption of a building usingmore » a conventional all-air system to determine the proportional energy savings. For proper handling of the latent load, a dedicated outside air system (DOAS) was used as an alternative to Fan Coil Unit (FCU). A comparison of energy consumption calculated that the radiant system was 17.5 % more efficient than a conventional all-air system and that a 30% savings was achieved by using a DOAS system compared with a conventional system. Computational Fluid Dynamics (CFD) simulation was performed to evaluate indoor air quality and thermal comfort. It was found that a radiant system offers more uniform temperatures, as well as a better mean air temperature range, than a conventional system. To further enhance the energy savings in the radiant system, different operational strategies were analyzed based on thermal analysis using EnergyPlus. Lastly, the energy savings achieved in this parametric run were more than 10% compared with a conventional all-air system.« less

  10. Infrared characteristics and flow field of the exhaust plume outside twin engine nozzle

    NASA Astrophysics Data System (ADS)

    Feng, Yun-song

    2016-01-01

    For mastery of infrared radiation characteristics and flow field of exhaust plume of twin engine nozzles, first, a physical model of the double rectangular nozzles is established with the Gambit, and the mathematical model of flow field is determined. Secondly, software Fluent6.3 is used to simulated the 3-D exterior flow field of the twin engine nozzles, and the datum of flow field, such as temperature, pressure and density, are obtained. Finally, based on the plume temperature, the exhaust plume space is divided. The exhaust plume is equivalent to a gray-body. A calculating model of the plume infrared radiation is established, and the plume infrared radiation characteristics are calculated by the software MATLAB, then the spatial distribution curves are drawn. The result improves that with the height increasing the temperature, press and infrared radiant intensity diminish. Compared with engine afterburning condition, temperature and infrared radiant intensity increases and press has no obvious change.

  11. Company's Unusual Plan to Package Commercial Software with Business Textbooks Produces a Measure of Success.

    ERIC Educational Resources Information Center

    Watkins, Beverly T.

    1992-01-01

    Course Technology Inc. has developed 10 products combining textbooks with commercial software for college accounting, business, computer science, and statistics courses. Five of the products use Lotus 1-2-3 spreadsheet software. The products have been positively received by teachers and students. (DB)

  12. ESSCOTS for Learning: Transforming Commercial Software into Powerful Educational Tools.

    ERIC Educational Resources Information Center

    McArthur, David; And Others

    1995-01-01

    Gives an overview of Educational Support Systems based on commercial off-the-shelf software (ESSCOTS), and discusses the benefits of developing such educational software. Presents results of a study that revealed the learning processes of middle and high school students who used a geographical information system. (JMV)

  13. Towards the Integration of APECS with VE-Suite to Create a Comprehensive Virtual Engineering Environment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McCorkle, D.; Yang, C.; Jordan, T.

    2007-06-01

    Modeling and simulation tools are becoming pervasive in the process engineering practice of designing advanced power generation facilities. These tools enable engineers to explore many what-if scenarios before cutting metal or constructing a pilot scale facility. While such tools enable investigation of crucial plant design aspects, typical commercial process simulation tools such as Aspen Plus®, gPROMS®, and HYSYS® still do not explore some plant design information, including computational fluid dynamics (CFD) models for complex thermal and fluid flow phenomena, economics models for policy decisions, operational data after the plant is constructed, and as-built information for use in as-designed models. Softwaremore » tools must be created that allow disparate sources of information to be integrated if environments are to be constructed where process simulation information can be accessed. At the Department of Energy’s (DOE) National Energy Technology Laboratory (NETL), the Advanced Process Engineering Co-Simulator (APECS) has been developed as an integrated software suite that combines process simulation (e.g., Aspen Plus) and high-fidelity equipment simulation (e.g., Fluent® CFD), together with advanced analysis capabilities including case studies, sensitivity analysis, stochastic simulation for risk/uncertainty analysis, and multi-objective optimization. In this paper, we discuss the initial phases of integrating APECS with the immersive and interactive virtual engineering software, VE-Suite, developed at Iowa State University and Ames Laboratory. VE-Suite utilizes the ActiveX (OLE Automation) controls in Aspen Plus wrapped by the CASI library developed by Reaction Engineering International to run the process simulation and query for unit operation results. This integration permits any application that uses the VE-Open interface to integrate with APECS co-simulations, enabling construction of the comprehensive virtual engineering environment needed for the rapid engineering of advanced power generation facilities.« less

  14. gr-MRI: A software package for magnetic resonance imaging using software defined radios

    NASA Astrophysics Data System (ADS)

    Hasselwander, Christopher J.; Cao, Zhipeng; Grissom, William A.

    2016-09-01

    The goal of this work is to develop software that enables the rapid implementation of custom MRI spectrometers using commercially-available software defined radios (SDRs). The developed gr-MRI software package comprises a set of Python scripts, flowgraphs, and signal generation and recording blocks for GNU Radio, an open-source SDR software package that is widely used in communications research. gr-MRI implements basic event sequencing functionality, and tools for system calibrations, multi-radio synchronization, and MR signal processing and image reconstruction. It includes four pulse sequences: a single-pulse sequence to record free induction signals, a gradient-recalled echo imaging sequence, a spin echo imaging sequence, and an inversion recovery spin echo imaging sequence. The sequences were used to perform phantom imaging scans with a 0.5 Tesla tabletop MRI scanner and two commercially-available SDRs. One SDR was used for RF excitation and reception, and the other for gradient pulse generation. The total SDR hardware cost was approximately 2000. The frequency of radio desynchronization events and the frequency with which the software recovered from those events was also measured, and the SDR's ability to generate frequency-swept RF waveforms was validated and compared to the scanner's commercial spectrometer. The spin echo images geometrically matched those acquired using the commercial spectrometer, with no unexpected distortions. Desynchronization events were more likely to occur at the very beginning of an imaging scan, but were nearly eliminated if the user invoked the sequence for a short period before beginning data recording. The SDR produced a 500 kHz bandwidth frequency-swept pulse with high fidelity, while the commercial spectrometer produced a waveform with large frequency spike errors. In conclusion, the developed gr-MRI software can be used to develop high-fidelity, low-cost custom MRI spectrometers using commercially-available SDRs.

  15. Transitional hemodynamics in intracranial aneurysms - Comparative velocity investigations with high resolution lattice Boltzmann simulations, normal resolution ANSYS simulations, and MR imaging.

    PubMed

    Jain, Kartik; Jiang, Jingfeng; Strother, Charles; Mardal, Kent-André

    2016-11-01

    Blood flow in intracranial aneurysms has, until recently, been considered to be disturbed but still laminar. Recent high resolution computational studies have demonstrated, in some situations, however, that the flow may exhibit high frequency fluctuations that resemble weakly turbulent or transitional flow. Due to numerous assumptions required for simplification in computational fluid dynamics (CFD) studies, the occurrence of these events, in vivo, remains unsettled. The detection of these fluctuations in aneurysmal blood flow, i.e., hemodynamics by CFD, poses additional challenges as such phenomena cannot be captured in clinical data acquisition with magnetic resonance (MR) due to inadequate temporal and spatial resolutions. The authors' purpose was to address this issue by comparing results from highly resolved simulations, conventional resolution laminar simulations, and MR measurements, identify the differences, and identify their causes. Two aneurysms in the basilar artery, one with disturbed yet laminar flow and the other with transitional flow, were chosen. One set of highly resolved direct numerical simulations using the lattice Boltzmann method (LBM) and another with adequate resolutions under laminar flow assumption were conducted using a commercially available ANSYS Fluent solver. The velocity fields obtained from simulation results were qualitatively and statistically compared against each other and with MR acquisition. Results from LBM, ANSYS Fluent, and MR agree well qualitatively and quantitatively for one of the aneurysms with laminar flow in which fluctuations were <80 Hz. The comparisons for the second aneurysm with high fluctuations of > ∼ 600 Hz showed vivid differences between LBM, ANSYS Fluent, and magnetic resonance imaging. After ensemble averaging and down-sampling to coarser space and time scales, these differences became minimal. A combination of MR derived data and CFD can be helpful in estimating the hemodynamic environment of intracranial aneurysms. Adequately resolved CFD would suffice gross assessment of hemodynamics, potentially in a clinical setting, and highly resolved CFD could be helpful in a detailed and retrospective understanding of the physiological mechanisms.

  16. Application of CFD (Fluent) to LNG spills into geometrically complex environments.

    PubMed

    Gavelli, Filippo; Bullister, Edward; Kytomaa, Harri

    2008-11-15

    Recent discussions on the fate of LNG spills into impoundments have suggested that the commonly used combination of SOURCE5 and DEGADIS to predict the flammable vapor dispersion distances is not accurate, as it does not account for vapor entrainment by wind. SOURCE5 assumes the vapor layer to grow upward uniformly in the form of a quiescent saturated gas cloud that ultimately spills over impoundment walls. The rate of spillage is then used as the source term for DEGADIS. A more rigorous approach to predict the flammable vapor dispersion distance is to use a computational fluid dynamics (CFD) model. CFD codes can take into account the physical phenomena that govern the fate of LNG spills into impoundments, such as the mixing between air and the evaporated gas. Before a CFD code can be proposed as an alternate method for the prediction of flammable vapor cloud distances, it has to be validated with proper experimental data. This paper describes the use of Fluent, a widely-used commercial CFD code, to simulate one of the tests in the "Falcon" series of LNG spill tests. The "Falcon" test series was the only series that specifically addressed the effects of impoundment walls and construction obstructions on the behavior and dispersion of the vapor cloud. Most other tests, such as the Coyote and the Burro series, involved spills onto water and relatively flat ground. The paper discusses the critical parameters necessary for a CFD model to accurately predict the behavior of a cryogenic spill in a geometrically complex domain, and presents comparisons between the gas concentrations measured during the Falcon-1 test and those predicted using Fluent. Finally, the paper discusses the effect vapor barriers have in containing part of the spill thereby shortening the ignitable vapor cloud and therefore the required hazard area. This issue was addressed by comparing the Falcon-1 simulation (spill into the impoundment) with the simulation of an identical spill without any impoundment walls, or obstacles within the impoundment area.

  17. Preliteracy signatures of poor-reading abilities in resting-state EEG

    PubMed Central

    Schiavone, Giuseppina; Linkenkaer-Hansen, Klaus; Maurits, Natasha M.; Plakas, Anna; Maassen, Ben A. M.; Mansvelder, Huibert D.; van der Leij, Aryan; van Zuijen, Titia L.

    2014-01-01

    The hereditary character of dyslexia suggests the presence of putative underlying neural anomalies already in preliterate age. Here, we investigated whether early neurophysiological correlates of future reading difficulties—a hallmark of dyslexia—could be identified in the resting-state EEG of preliterate children. The children in this study were recruited at birth and classified on the basis of parents' performance on reading tests to be at-risk of becoming poor readers (n = 48) or not (n = 14). Eyes-open rest EEG was measured at the age of 3 years, and the at-risk children were divided into fluent readers (n = 24) and non-fluent readers (n = 24) after reading assessment at their third grade of school. We found that fluent readers and non-fluent readers differed in normalized spectral amplitude. Non-fluent readers were characterized by lower amplitude in the delta-1 frequency band (0.5–2 Hz) and higher amplitude in the alpha-1 band (6–8 Hz) in multiple scalp regions compared to control and at-risk fluent readers. Interestingly, across groups these EEG biomarkers correlated with several behavioral test scores measured in the third grade. Specifically, the performance on reading fluency, phonological and orthographic tasks and rapid automatized naming task correlated positively with delta-1 and negatively with alpha-1. Together, our results suggest that combining family-risk status, neurophysiological testing and behavioral test scores in a longitudinal setting may help uncover physiological mechanisms implicated with neurodevelopmental disorders such as the predisposition to reading disabilities. PMID:25285075

  18. Effects of word frequency and phonological neighborhood characteristics on confrontation naming in children who stutter and normally fluent peers.

    PubMed

    Ratner, Nan Bernstein; Newman, Rochelle; Strekas, Amy

    2009-12-01

    In a prior study (Newman & Bernstein Ratner, 2007), we examined the effects of word frequency and phonological neighborhood characteristics on confrontation naming latency, accuracy and fluency in adults who stutter and typically fluent speakers. A small difference in accuracy favoring fluent adults was noted, but no other patterns differentiated fluent speaker responses from those obtained from the adults who stutter. Because lexical organization or retrieval differences might be more easily observed in less mature language users, we replicated the experiment using 15 children who stutter (ages 4;10 16;2) and age- and gender-matched peers. Results replicated the earlier study: the two groups of participants showed strikingly similar patterns of responses based on word frequency and neighborhood characteristics. There were also no differences in naming accuracy overall between the two groups. Given our results and those of other researchers who have explored the impact of neighborhood variables on lexical retrieval in people who stutter, we suggest that differences between language production in PWS and fluent speakers are not likely to involve atypical phonological organization of lexical neighborhoods. After reading this article, the reader will be able to: (1) define and illustrate words that have differing frequency and phonological neighborhood characteristics; (2) evaluate whether or not children who stutter appear to organize their mental lexicons differently than those of children who are typically fluent; (3) suggest future areas of research into language processing in people who stutter.

  19. 76 FR 36919 - Proof of Concept Demonstration for Electronic Reporting of Clean Water Act Compliance Monitoring...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-23

    ... commercial products or services of any third-party software providers. Proof of Concept Demonstration for..., protocols, and specifications for the Exchange Network's data exchange services, the software provider shall... demonstration will focus the electronic transmission of NPDES DMRs from a third-party commercial software...

  20. Validation, Optimization and Simulation of a Solar Thermoelectric Generator Model

    NASA Astrophysics Data System (ADS)

    Madkhali, Hadi Ali; Hamil, Ali; Lee, HoSung

    2017-12-01

    This study explores thermoelectrics as a viable option for small-scale solar thermal applications. Thermoelectric technology is based on the Seebeck effect, which states that a voltage is induced when a temperature gradient is applied to the junctions of two differing materials. This research proposes to analyze, validate, simulate, and optimize a prototype solar thermoelectric generator (STEG) model in order to increase efficiency. The intent is to further develop STEGs as a viable and productive energy source that limits pollution and reduces the cost of energy production. An empirical study (Kraemer et al. in Nat Mater 10:532, 2011) on the solar thermoelectric generator reported a high efficiency performance of 4.6%. The system had a vacuum glass enclosure, a flat panel (absorber), thermoelectric generator and water circulation for the cold side. The theoretical and numerical approach of this current study validated the experimental results from Kraemer's study to a high degree. The numerical simulation process utilizes a two-stage approach in ANSYS software for Fluent and Thermal-Electric Systems. The solar load model technique uses solar radiation under AM 1.5G conditions in Fluent. This analytical model applies Dr. Ho Sung Lee's theory of optimal design to improve the performance of the STEG system by using dimensionless parameters. Applying this theory, using two cover glasses and radiation shields, the STEG model can achieve a highest efficiency of 7%.

  1. 48 CFR 208.7400 - Scope of subpart.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... OF DEFENSE ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Enterprise Software... commercial software and software maintenance, including software and software maintenance that is acquired...

  2. 48 CFR 208.7400 - Scope of subpart.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... OF DEFENSE ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Enterprise Software... commercial software and software maintenance, including software and software maintenance that is acquired...

  3. 48 CFR 208.7400 - Scope of subpart.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... OF DEFENSE ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Enterprise Software... commercial software and software maintenance, including software and software maintenance that is acquired...

  4. 48 CFR 208.7400 - Scope of subpart.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... OF DEFENSE ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Enterprise Software... commercial software and software maintenance, including software and software maintenance that is acquired...

  5. Emotional reactivity and regulation associated with fluent and stuttered utterances of preschool-age children who stutter

    PubMed Central

    Jones, Robin M.; Conture, Edward G.; Walden, Tedra A.

    2014-01-01

    Purpose The purpose of this study was to assess the relation between emotional reactivity and regulation associated with fluent and stuttered utterances of preschool-age children who stutter (CWS) and those who do not (CWNS). Participants Participants were eight 3 to 6-year old CWS and eight CWNS of comparable age and gender. Methods Participants were exposed to three emotion-inducing overheard conversations—neutral, angry and happy—and produced a narrative following each overheard conversation. From audio-video recordings of these narratives, coded behavioral analysis of participants’ negative and positive affect and emotion regulation associated with stuttered and fluent utterances was conducted. Results Results indicated that CWS were significantly more likely to exhibit emotion regulation attempts prior to and during their fluent utterances following the happy as compared to the negative condition, whereas CWNS displayed the opposite pattern. Within-group assessment indicated that CWS were significantly more likely to display negative emotion prior to and during their stuttered than fluent utterances, particularly following the positive overheard conversation. Conclusions After exposure to emotional-inducing overheard conversations, changes in preschool-age CWS’s emotion and emotion regulatory attempts were associated with the fluency of their utterances. PMID:24630144

  6. When will a stuttering moment occur? The determining role of speech motor preparation.

    PubMed

    Vanhoutte, Sarah; Cosyns, Marjan; van Mierlo, Pieter; Batens, Katja; Corthals, Paul; De Letter, Miet; Van Borsel, John; Santens, Patrick

    2016-06-01

    The present study aimed to evaluate whether increased activity related to speech motor preparation preceding fluently produced words reflects a successful compensation strategy in stuttering. For this purpose, a contingent negative variation (CNV) was evoked during a picture naming task and measured by use of electro-encephalography. A CNV is a slow, negative event-related potential known to reflect motor preparation generated by the basal ganglia-thalamo-cortical (BGTC) - loop. In a previous analysis, the CNV of 25 adults with developmental stuttering (AWS) was significantly increased, especially over the right hemisphere, compared to the CNV of 35 fluent speakers (FS) when both groups were speaking fluently (Vanhoutte et al., (2015) doi: 10.1016/j.neuropsychologia.2015.05.013). To elucidate whether this increase is a compensation strategy enabling fluent speech in AWS, the present analysis evaluated the CNV of 7 AWS who stuttered during this picture naming task. The CNV preceding AWS stuttered words was statistically compared to the CNV preceding AWS fluent words and FS fluent words. Though no difference emerged between the CNV of the AWS stuttered words and the FS fluent words, a significant reduction was observed when comparing the CNV preceding AWS stuttered words to the CNV preceding AWS fluent words. The latter seems to confirm the compensation hypothesis: the increased CNV prior to AWS fluent words is a successful compensation strategy, especially when it occurs over the right hemisphere. The words are produced fluently because of an enlarged activity during speech motor preparation. The left CNV preceding AWS stuttered words correlated negatively with stuttering frequency and severity suggestive for a link between the left BGTC - network and the stuttering pathology. Overall, speech motor preparatory activity generated by the BGTC - loop seems to have a determining role in stuttering. An important divergence between left and right hemisphere is hypothesized. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Non-developmental item computer systems and the malicious software threat

    NASA Technical Reports Server (NTRS)

    Bown, Rodney L.

    1991-01-01

    The following subject areas are covered: a DOD development system - the Army Secure Operating System; non-development commercial computer systems; security, integrity, and assurance of service (SI and A); post delivery SI and A and malicious software; computer system unique attributes; positive feedback to commercial computer systems vendors; and NDI (Non-Development Item) computers and software safety.

  8. Non-fluent speech following stroke is caused by impaired efference copy.

    PubMed

    Feenaughty, Lynda; Basilakos, Alexandra; Bonilha, Leonardo; den Ouden, Dirk-Bart; Rorden, Chris; Stark, Brielle; Fridriksson, Julius

    2017-09-01

    Efference copy is a cognitive mechanism argued to be critical for initiating and monitoring speech: however, the extent to which breakdown of efference copy mechanisms impact speech production is unclear. This study examined the best mechanistic predictors of non-fluent speech among 88 stroke survivors. Objective speech fluency measures were subjected to a principal component analysis (PCA). The primary PCA factor was then entered into a multiple stepwise linear regression analysis as the dependent variable, with a set of independent mechanistic variables. Participants' ability to mimic audio-visual speech ("speech entrainment response") was the best independent predictor of non-fluent speech. We suggest that this "speech entrainment" factor reflects integrity of internal monitoring (i.e., efference copy) of speech production, which affects speech initiation and maintenance. Results support models of normal speech production and suggest that therapy focused on speech initiation and maintenance may improve speech fluency for individuals with chronic non-fluent aphasia post stroke.

  9. Incorporating Software Requirements into the System RFP: Survey of RFP Language for Software by Topic, v. 2.0

    DTIC Science & Technology

    2009-05-01

    CDRL) System - Terminal S TMOS - SEIT CL TMOS - IA/ Crypto CL Space - Payload S Space - SEIT C Space - IA/ Crypto C Role Legend: CL...strategy for maintaining the currency of the technology (through Commercial off-the-shelf software (COTS) and other reusable Non-Developmental Items (NDI...the strategy for maintaining the currency of technology (e.g., through Commercial off-the-shelf software (COTS) insertion, technology refresh

  10. Fault Study of Valve Based on Test Analysis and Comparison

    NASA Astrophysics Data System (ADS)

    Cheng, Li; Yang, Wukui; Liang, Tao; Xu, Yu; Chen, Chao

    2017-10-01

    The valve of a certain type of small engine often has the fault phenomenon of abnormal vibration noise and can’t close under the specified pressure, which may cause the engine automatic stop because of valve incomplete close leading to fuel leakage during test and startup on the bench. By test study compared to imported valve with the same use function and test condition valve, and put forward the thinking of improving valve structure, compared no-improved valve to improved valve by adopting Fluent field simulation software. As a result, improved valve can restore close pressure of valve, restrain abnormal vibration noise phenomenon, and effectively compensate compression value of spring because of steel ball contacting position downward with valve casing.

  11. Numerical simulation of flow field in umbrella wind turbine

    NASA Astrophysics Data System (ADS)

    Daorina, Bao; Xiaoxue, Wang; Wei, Shang; Yadong, Liu; Daorina, Bao; Xiaoxue, Wang; Wei, Shang; Yadong, Liu

    2018-05-01

    Umbrella wind turbine can control the swept area by adjusting the shrinking angle of the rotor so as to ensure that output power is near the rated value. This is very helpful for the utilization of wind energy in sandstorms and typhoon-prone areas of our country. In this paper, Fluent software is used to simulate the velocity field and pressure field of 5kW Umbrella Wind Turbine at 0° 45°and 60°angle of contraction. The results provide a theoretical basis for further improving the power adjustment mechanism of Umbrella Wind Turbines, At the same time, it also provide a reference for our country to perfect the wind energy utilization system about the typhoon environment in the coastal areas.

  12. Mathematical modeling of flow in the working part of an acousto-convective drying system

    NASA Astrophysics Data System (ADS)

    Kravchenko, A. S.; Zhilin, A. A.; Fedorova, N. N.

    2018-03-01

    The objective of this study was to numerically simulate the nonstationary processes occurring in the acoustic-convective dryer (ACD) channel. In the present work, the problem was solved numerically in a three-dimensional formulation taking into account all features of the ACD duct in real geometry. The processes occurring in the ACD duct were simulated using the ANSYS Fluent 18.0 software. The numerical experiments provided an aggregate picture of the working gas flow in the ACD duct with the features near the subsonic nozzle and the cavity. The results of the numerical calculations were compared with experimental data. The best agreement with the experimental data was obtained for the viscosity model neglecting turbulent effects.

  13. Mathematical modeling of the process of filling a mold during injection molding of ceramic products

    NASA Astrophysics Data System (ADS)

    Kulkov, S. N.; Korobenkov, M. V.; Bragin, N. A.

    2015-10-01

    Using the software package Fluent it have been predicted of the filling of a mold in injection molding of ceramic products is of great importance, because the strength of the final product is directly related to the presence of voids in the molding, making possible early prediction of inaccuracies in the mold prior to manufacturing. The calculations were performed in the formulation of mathematical modeling of hydrodynamic turbulent process of filling a predetermined volume of a viscous liquid. The model used to determine the filling forms evaluated the influence of density and viscosity of the feedstock, and the injection pressure on the mold filling process to predict the formation of voids in the area caused by the shape defect geometry.

  14. Two-dimensional CFD modeling of the heat and mass transfer process during sewage sludge drying in a solar dryer

    NASA Astrophysics Data System (ADS)

    Krawczyk, Piotr; Badyda, Krzysztof

    2011-12-01

    The paper presents key assumptions of the mathematical model which describes heat and mass transfer phenomena in a solar sewage drying process, as well as techniques used for solving this model with the Fluent computational fluid dynamics (CFD) software. Special attention was paid to implementation of boundary conditions on the sludge surface, which is a physical boundary between the gaseous phase - air, and solid phase - dried matter. Those conditions allow to model heat and mass transfer between the media during first and second drying stages. Selection of the computational geometry is also discussed - it is a fragment of the entire drying facility. Selected modelling results are presented in the final part of the paper.

  15. Experimental Study and CFD Simulation of a 2D Circulating Fluidized Bed

    NASA Astrophysics Data System (ADS)

    Kallio, S.; Guldén, M.; Hermanson, A.

    Computational fluid dynamics (CFD) gains popularity in fluidized bed modeling. For model validation, there is a need of detailed measurements under well-defined conditions. In the present study, experiments were carried out in a 40 em wide and 3 m high 2D circulating fluidized bed. Two experiments were simulated by means of the Eulerian multiphase models of the Fluent CFD software. The vertical pressure and solids volume fraction profiles and the solids circulation rate obtained from the simulation were compared to the experimental results. In addition, lateral volume fraction profiles could be compared. The simulated CFB flow patterns and the profiles obtained from simulations were in general in a good agreement with the experimental results.

  16. Computational Analysis of an effect of aerodynamic pressure on the side view mirror geometry

    NASA Astrophysics Data System (ADS)

    Murukesavan, P.; Mu'tasim, M. A. N.; Sahat, I. M.

    2013-12-01

    This paper describes the evaluation of aerodynamic flow effects on side mirror geometry for a passenger car using ANSYS Fluent CFD simulation software. Results from analysis of pressure coefficient on side view mirror designs is evaluated to analyse the unsteady forces that cause fluctuations to mirror surface and image blurring. The fluctuation also causes drag forces that increase the overall drag coefficient, with an assumption resulting in higher fuel consumption and emission. Three features of side view mirror design were investigated with two input velocity parameters of 17 m/s and 33 m/s. Results indicate that the half-sphere design shows the most effective design with less pressure coefficient fluctuation and drag coefficient.

  17. Design and Analysis of Horizontal Axial Flow Motor Shroud

    NASA Astrophysics Data System (ADS)

    Wang, Shiming; Shen, Yu

    2018-01-01

    The wind turbine diffuser can increase the wind energy utilization coefficient of the wind turbine, and the addition of the shroud to the horizontal axis wind turbine also plays a role of accelerating the flow of the condensate. First, the structure of the shroud was designed and then modeled in gambit. The fluent software was used to establish the mathematical model for simulation. The length of the shroud and the opening angle of the shroud are analyzed to determine the best shape of the shroud. Then compared the efficiency with or without the shroud, through the simulation and the experiment of the water tank, it is confirmed that the horizontal axis of the shroud can improve the hydrodynamic performance.

  18. Heat, mass and force flows in supersonic shockwave interaction

    NASA Astrophysics Data System (ADS)

    Dixon, John Michael

    There is no cost effective way to deliver a payload to space and, with rising fuel prices, currently the price to travel commercially is also becoming more prohibitive to the public. During supersonic flight, compressive shock waves form around the craft which could be harnessed to deliver an additional lift on the craft. Using a series of hanging plates below a lifting wing design, the total lift generated can be increased above conventional values, while still maintaining a similar lift-to-drag ratio. Here, we study some of the flows involved in supersonic shockwave interaction. This analysis uses ANSYS Fluent Computational Fluid Dynamics package as the modeler. Our findings conclude an increase of up to 30% lift on the modeled craft while maintaining the lift-to-drag profile of the unmodified lifting wing. The increase in lift when utilizing the shockwave interaction could increase transport weight and reduce fuel cost for space and commercial flight, as well as mitigating negative effects associated with supersonic travel.

  19. gr-MRI: A software package for magnetic resonance imaging using software defined radios.

    PubMed

    Hasselwander, Christopher J; Cao, Zhipeng; Grissom, William A

    2016-09-01

    The goal of this work is to develop software that enables the rapid implementation of custom MRI spectrometers using commercially-available software defined radios (SDRs). The developed gr-MRI software package comprises a set of Python scripts, flowgraphs, and signal generation and recording blocks for GNU Radio, an open-source SDR software package that is widely used in communications research. gr-MRI implements basic event sequencing functionality, and tools for system calibrations, multi-radio synchronization, and MR signal processing and image reconstruction. It includes four pulse sequences: a single-pulse sequence to record free induction signals, a gradient-recalled echo imaging sequence, a spin echo imaging sequence, and an inversion recovery spin echo imaging sequence. The sequences were used to perform phantom imaging scans with a 0.5Tesla tabletop MRI scanner and two commercially-available SDRs. One SDR was used for RF excitation and reception, and the other for gradient pulse generation. The total SDR hardware cost was approximately $2000. The frequency of radio desynchronization events and the frequency with which the software recovered from those events was also measured, and the SDR's ability to generate frequency-swept RF waveforms was validated and compared to the scanner's commercial spectrometer. The spin echo images geometrically matched those acquired using the commercial spectrometer, with no unexpected distortions. Desynchronization events were more likely to occur at the very beginning of an imaging scan, but were nearly eliminated if the user invoked the sequence for a short period before beginning data recording. The SDR produced a 500kHz bandwidth frequency-swept pulse with high fidelity, while the commercial spectrometer produced a waveform with large frequency spike errors. In conclusion, the developed gr-MRI software can be used to develop high-fidelity, low-cost custom MRI spectrometers using commercially-available SDRs. Copyright © 2016. Published by Elsevier Inc.

  20. Cross-Modal Matching of Audio-Visual German and French Fluent Speech in Infancy

    PubMed Central

    Kubicek, Claudia; Hillairet de Boisferon, Anne; Dupierrix, Eve; Pascalis, Olivier; Lœvenbruck, Hélène; Gervain, Judit; Schwarzer, Gudrun

    2014-01-01

    The present study examined when and how the ability to cross-modally match audio-visual fluent speech develops in 4.5-, 6- and 12-month-old German-learning infants. In Experiment 1, 4.5- and 6-month-old infants’ audio-visual matching ability of native (German) and non-native (French) fluent speech was assessed by presenting auditory and visual speech information sequentially, that is, in the absence of temporal synchrony cues. The results showed that 4.5-month-old infants were capable of matching native as well as non-native audio and visual speech stimuli, whereas 6-month-olds perceived the audio-visual correspondence of native language stimuli only. This suggests that intersensory matching narrows for fluent speech between 4.5 and 6 months of age. In Experiment 2, auditory and visual speech information was presented simultaneously, therefore, providing temporal synchrony cues. Here, 6-month-olds were found to match native as well as non-native speech indicating facilitation of temporal synchrony cues on the intersensory perception of non-native fluent speech. Intriguingly, despite the fact that audio and visual stimuli cohered temporally, 12-month-olds matched the non-native language only. Results were discussed with regard to multisensory perceptual narrowing during the first year of life. PMID:24586651

  1. Software Assurance Challenges for the Commercial Crew Program

    NASA Technical Reports Server (NTRS)

    Cuyno, Patrick; Malnick, Kathy D.; Schaeffer, Chad E.

    2015-01-01

    This paper will provide a description of some of the challenges NASA is facing in providing software assurance within the new commercial space services paradigm, namely with the Commercial Crew Program (CCP). The CCP will establish safe, reliable, and affordable access to the International Space Station (ISS) by purchasing a ride from commercial companies. The CCP providers have varying experience with software development in safety-critical space systems. NASA's role in providing effective software assurance support to the CCP providers is critical to the success of CCP. These challenges include funding multiple vehicles that execute in parallel and have different rules of engagement, multiple providers with unique proprietary concerns, providing equivalent guidance to all providers, permitting alternates to NASA standards, and a large number of diverse stakeholders. It is expected that these challenges will exist in future programs, especially if the CCP paradigm proves successful. The proposed CCP approach to address these challenges includes a risk-based assessment with varying degrees of engagement and a distributed assurance model. This presentation will describe NASA IV&V Program's software assurance support and responses to these challenges.

  2. Finding Diamonds in the Rough

    NASA Technical Reports Server (NTRS)

    2000-01-01

    HighTower Software, Inc. has developed a commercial software application originally designed at JPL that helps users identify deviations from norms out of massive quantities of data. The commercial product is known as CyberGrid and the same software is still supporting NASA's Voyager, Galileo and Cassini missions. CyberGrid generates 3-D graphs of data and has been used in AIDS research as well as e-commerce applications.

  3. Automatic Commercial Permit Sets

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Grana, Paul

    Final report for Folsom Labs’ Solar Permit Generator project, which has successfully completed, resulting in the development and commercialization of a software toolkit within the cloud-based HelioScope software environment that enables solar engineers to automatically generate and manage draft documents for permit submission.

  4. Reproducing American Sign Language sentences: cognitive scaffolding in working memory

    PubMed Central

    Supalla, Ted; Hauser, Peter C.; Bavelier, Daphne

    2014-01-01

    The American Sign Language Sentence Reproduction Test (ASL-SRT) requires the precise reproduction of a series of ASL sentences increasing in complexity and length. Error analyses of such tasks provides insight into working memory and scaffolding processes. Data was collected from three groups expected to differ in fluency: deaf children, deaf adults and hearing adults, all users of ASL. Quantitative (correct/incorrect recall) and qualitative error analyses were performed. Percent correct on the reproduction task supports its sensitivity to fluency as test performance clearly differed across the three groups studied. A linguistic analysis of errors further documented differing strategies and bias across groups. Subjects' recall projected the affordance and constraints of deep linguistic representations to differing degrees, with subjects resorting to alternate processing strategies when they failed to recall the sentence correctly. A qualitative error analysis allows us to capture generalizations about the relationship between error pattern and the cognitive scaffolding, which governs the sentence reproduction process. Highly fluent signers and less-fluent signers share common chokepoints on particular words in sentences. However, they diverge in heuristic strategy. Fluent signers, when they make an error, tend to preserve semantic details while altering morpho-syntactic domains. They produce syntactically correct sentences with equivalent meaning to the to-be-reproduced one, but these are not verbatim reproductions of the original sentence. In contrast, less-fluent signers tend to use a more linear strategy, preserving lexical status and word ordering while omitting local inflections, and occasionally resorting to visuo-motoric imitation. Thus, whereas fluent signers readily use top-down scaffolding in their working memory, less fluent signers fail to do so. Implications for current models of working memory across spoken and signed modalities are considered. PMID:25152744

  5. Report: Scientific Software.

    ERIC Educational Resources Information Center

    Borman, Stuart A.

    1985-01-01

    Discusses various aspects of scientific software, including evaluation and selection of commercial software products; program exchanges, catalogs, and other information sources; major data analysis packages; statistics and chemometrics software; and artificial intelligence. (JN)

  6. Writing Blocks and Tacit Knowledge.

    ERIC Educational Resources Information Center

    Boice, Robert

    1993-01-01

    A review of the literature on writing block looks at two kinds: inability to write in a timely, fluent fashion, and reluctance by academicians to assist others in writing. Obstacles to fluent writing are outlined, four historical trends in treating blocks are discussed, and implications are examined. (MSE)

  7. Identifying controlling variables for math computation fluency through experimental analysis: the interaction of stimulus control and reinforcing consequences.

    PubMed

    Hofstadter-Duke, Kristi L; Daly, Edward J

    2015-03-01

    This study investigated a method for conducting experimental analyses of academic responding. In the experimental analyses, academic responding (math computation), rather than problem behavior, was reinforced across conditions. Two separate experimental analyses (one with fluent math computation problems and one with non-fluent math computation problems) were conducted with three elementary school children using identical contingencies while math computation rate was measured. Results indicate that the experimental analysis with non-fluent problems produced undifferentiated responding across participants; however, differentiated responding was achieved for all participants in the experimental analysis with fluent problems. A subsequent comparison of the single-most effective condition from the experimental analyses replicated the findings with novel computation problems. Results are discussed in terms of the critical role of stimulus control in identifying controlling consequences for academic deficits, and recommendations for future research refining and extending experimental analysis to academic responding are made. © The Author(s) 2014.

  8. Rosin-Rammler Distributions in ANSYS Fluent

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dunham, Ryan Q.

    In Health Physics monitoring, particles need to be collected and tracked. One method is to predict the motion of potential health hazards with computer models. Particles released from various sources within a glove box can become a respirable health hazard if released into the area surrounding a glove box. The goal of modeling the aerosols in a glove box is to reduce the hazards associated with a leak in the glove box system. ANSYS Fluent provides a number of tools for modeling this type of environment. Particles can be released using injections into the flow path with turbulent properties. Themore » models of particle tracks can then be used to predict paths and concentrations of particles within the flow. An attempt to understand and predict the handling of data by Fluent was made, and results iteratively tracked. Trends in data were studied to comprehend the final results. The purpose of the study was to allow a better understanding of the operation of Fluent for aerosol modeling for future application in many fields.« less

  9. Mixed convection of nanofluids in a lid-driven rough cavity

    NASA Astrophysics Data System (ADS)

    Guo, Zhimeng; Wang, Jinyu; Mozumder, Aloke K.; Das, Prodip K.

    2017-06-01

    Mixed convection heat transfer and fluid flow of air, water or oil in enclosures have been studied extensively using experimental and numerical means for many years due to their ever-increasing applications in many engineering fields. In comparison, little effort has been given to the problem of mixed convection of nanofluids in spite of several applications in solar collectors, electronic cooling, lubrication technologies, food processing, and nuclear reactors. Mixed convection of nanofluids is a challenging problem due to the complex interactions among inertia, viscous, and buoyancy forces. In this study, mixed convection of nanofluids in a lid-driven square cavity with sinusoidal roughness elements at the bottom is studied numerically using the Navier-Stokes equations with the Boussinesq approximation. The numerical model is developed using commercial finite volume software ANSYS-FLUENT for Al2O3-water and CuO-water nanofluids inside a square cavity with various roughness elements. The effects of number and amplitude of roughness elements on the heat transfer and fluid flow are analysed for various volume concentrations of Al2O3 and CuO nanoparticles. The flow fields, temperature fields, and heat transfer rates are examined for different values of Rayleigh and Reynolds numbers. The outcome of this study provides some important insight into the heat transfer behaviour of Al2O3-water and CuO-water nanofluids inside a lid-driven rough cavity. This knowledge can be further used in developing novel geometries with enhanced and controlled heat transfer for solar collectors, electronic cooling, and food processing industries.

  10. Performance evaluation of radiant cooling system integrated with air system under different operational strategies

    DOE PAGES

    Khan, Yasin; Khare, Vaibhav Rai; Mathur, Jyotirmay; ...

    2015-03-26

    The paper describes a parametric study developed to estimate the energy savings potential of a radiant cooling system installed in a commercial building in India. The study is based on numerical modeling of a radiant cooling system installed in an Information Technology (IT) office building sited in the composite climate of Hyderabad. To evaluate thermal performance and energy consumption, simulations were carried out using the ANSYS FLUENT and EnergyPlus softwares, respectively. The building model was calibrated using the measured data for the installed radiant system. Then this calibrated model was used to simulate the energy consumption of a building usingmore » a conventional all-air system to determine the proportional energy savings. For proper handling of the latent load, a dedicated outside air system (DOAS) was used as an alternative to Fan Coil Unit (FCU). A comparison of energy consumption calculated that the radiant system was 17.5 % more efficient than a conventional all-air system and that a 30% savings was achieved by using a DOAS system compared with a conventional system. Computational Fluid Dynamics (CFD) simulation was performed to evaluate indoor air quality and thermal comfort. It was found that a radiant system offers more uniform temperatures, as well as a better mean air temperature range, than a conventional system. To further enhance the energy savings in the radiant system, different operational strategies were analyzed based on thermal analysis using EnergyPlus. Lastly, the energy savings achieved in this parametric run were more than 10% compared with a conventional all-air system.« less

  11. AN EVALUATION OF FIVE COMMERCIAL IMMUNOASSAY DATA ANALYSIS SOFTWARE SYSTEMS

    EPA Science Inventory

    An evaluation of five commercial software systems used for immunoassay data analysis revealed numerous deficiencies. Often, the utility of statistical output was compromised by poor documentation. Several data sets were run through each system using a four-parameter calibration f...

  12. Common Data Acquisition Systems (DAS) Software Development for Rocket Propulsion Test (RPT) Test Facilities

    NASA Technical Reports Server (NTRS)

    Hebert, Phillip W., Sr.; Davis, Dawn M.; Turowski, Mark P.; Holladay, Wendy T.; Hughes, Mark S.

    2012-01-01

    The advent of the commercial space launch industry and NASA's more recent resumption of operation of Stennis Space Center's large test facilities after thirty years of contractor control resulted in a need for a non-proprietary data acquisition systems (DAS) software to support government and commercial testing. The software is designed for modularity and adaptability to minimize the software development effort for current and future data systems. An additional benefit of the software's architecture is its ability to easily migrate to other testing facilities thus providing future commonality across Stennis. Adapting the software to other Rocket Propulsion Test (RPT) Centers such as MSFC, White Sands, and Plumbrook Station would provide additional commonality and help reduce testing costs for NASA. Ultimately, the software provides the government with unlimited rights and guarantees privacy of data to commercial entities. The project engaged all RPT Centers and NASA's Independent Verification & Validation facility to enhance product quality. The design consists of a translation layer which provides the transparency of the software application layers to underlying hardware regardless of test facility location and a flexible and easily accessible database. This presentation addresses system technical design, issues encountered, and the status of Stennis development and deployment.

  13. Performing Quantitative Imaging Acquisition, Analysis and Visualization Using the Best of Open Source and Commercial Software Solutions.

    PubMed

    Shenoy, Shailesh M

    2016-07-01

    A challenge in any imaging laboratory, especially one that uses modern techniques, is to achieve a sustainable and productive balance between using open source and commercial software to perform quantitative image acquisition, analysis and visualization. In addition to considering the expense of software licensing, one must consider factors such as the quality and usefulness of the software's support, training and documentation. Also, one must consider the reproducibility with which multiple people generate results using the same software to perform the same analysis, how one may distribute their methods to the community using the software and the potential for achieving automation to improve productivity.

  14. The Commercial Open Source Business Model

    NASA Astrophysics Data System (ADS)

    Riehle, Dirk

    Commercial open source software projects are open source software projects that are owned by a single firm that derives a direct and significant revenue stream from the software. Commercial open source at first glance represents an economic paradox: How can a firm earn money if it is making its product available for free as open source? This paper presents the core properties of com mercial open source business models and discusses how they work. Using a commercial open source approach, firms can get to market faster with a superior product at lower cost than possible for traditional competitors. The paper shows how these benefits accrue from an engaged and self-supporting user community. Lacking any prior comprehensive reference, this paper is based on an analysis of public statements by practitioners of commercial open source. It forges the various anecdotes into a coherent description of revenue generation strategies and relevant business functions.

  15. Three-dimensional finite volume modelling of blood flow in simulated angular neck abdominal aortic aneurysm

    NASA Astrophysics Data System (ADS)

    Algabri, Y. A.; Rookkapan, S.; Chatpun, S.

    2017-09-01

    An abdominal aortic aneurysm (AAA) is considered a deadly cardiovascular disease that defined as a focal dilation of blood artery. The healthy aorta size is between 15 and 24 mm based on gender, bodyweight, and age. When the diameter increased to 30 mm or more, the rupture can occur if it is kept growing or untreated. Moreover, the proximal angular neck of aneurysm is categorized as a significant morphological feature with prime harmful effects on endovascular aneurysm repair (EVAR). Flow pattern in pathological vessel can influence the vascular intervention. The aim of this study is to investigate the blood flow behaviours in angular neck abdominal aortic aneurysm with simulated geometry based on patient’s information using computational fluid dynamics (CFD). The 3D angular neck AAA models have been designed by using SolidWorks Software. Consequently, CFD tools are used for simulating these 3D models of angular neck AAA in ANSYS FLUENT Software. Eventually, based on the results, we summarized that the CFD techniques have shown high performance in explaining and investigating the flow patterns for angular neck abdominal aortic aneurysm.

  16. Fluid dynamics simulation for design on sludge drying equipment

    NASA Astrophysics Data System (ADS)

    Li, Shuiping; Liang, Wang; Kai, Zhang

    2017-10-01

    Sludge drying equipment is a key component in the sludge drying disposal, the structure of drying equipment directly affects the drying disposal of the sludge, so it is necessary to analyse the performance of the drying equipment with different structure. Fluent software can be very convenient to get the distribution of the flow field and temperature field inside the drying equipment which reflects the performance of the structure. In this paper, the outlet position of the sludge and the shape of the sludge inlet are designed. The geometrical model of the drying equipment is established by using pre-processing software Gambit, and the meshing of the model is carried out. The Eulerian model is used to simulate the flow of each phase and the interaction between them, and the realizable turbulence model is used to simulate the turbulence of each phase. Finally, the simulation results of the scheme are compared and the optimal structure scheme is obtained, the operational requirement is proposed. The CFD theory provides a reliable basis for the drying equipment research and reduces the time and costs of the research.

  17. Flow Simulation of Modified Duct System Wind Turbines Installed on Vehicle

    NASA Astrophysics Data System (ADS)

    Rosly, N.; Mohd, S.; Zulkafli, M. F.; Ghafir, M. F. Abdul; Shamsudin, S. S.; Muhammad, W. N. A. Wan

    2017-10-01

    This study investigates the characteristics of airflow with a flow guide installed and output power generated by wind turbine system being installed on a pickup truck. The wind turbine models were modelled by using SolidWorks 2015 software. In order to investigate the characteristic of air flow inside the wind turbine system, a computer simulation (by using ANSYS Fluent software) is used. There were few models being designed and simulated, one without the rotor installed and another two with rotor installed in the wind turbine system. Three velocities being used for the simulation which are 16.7 m/s (60 km/h), 25 m/s (90 km/h) and 33.33 m/s (120 km/h). The study proved that the flow guide did give an impact to the output power produced by the wind turbine system. The predicted result from this study is the velocity of the air inside the ducting system of the present model is better that reference model. Besides, the flow guide implemented in the ducting system gives a big impact on the characteristics of the air flow.

  18. Achieving AFRL Universal FADEC Vision With Open Architecture Addressing Capability and Obsolescence for Military and Commercial Applications (Preprint)

    DTIC Science & Technology

    2006-11-01

    engines will involve a family of common components. It will consist of a real - time operating system and partitioned application software (AS...system will employ a standard hardware and software architecture. It will consist of a real time operating system and partitioned application...Inputs - Enables Large Cost Reduction 3. Software - FAA Certified Auto Code - Real Time Operating System - Commercial

  19. Emotional and physiological responses of fluent listeners while watching the speech of adults who stutter.

    PubMed

    Guntupalli, Vijaya K; Everhart, D Erik; Kalinowski, Joseph; Nanjundeswaran, Chayadevie; Saltuklaroglu, Tim

    2007-01-01

    People who stutter produce speech that is characterized by intermittent, involuntary part-word repetitions and prolongations. In addition to these signature acoustic manifestations, those who stutter often display repetitive and fixated behaviours outside the speech producing mechanism (e.g. in the head, arm, fingers, nares, etc.). Previous research has examined the attitudes and perceptions of those who stutter and people who frequently interact with them (e.g. relatives, parents, employers). Results have shown an unequivocal, powerful and robust negative stereotype despite a lack of defined differences in personality structure between people who stutter and normally fluent individuals. However, physiological investigations of listener responses during moments of stuttering are limited. There is a need for data that simultaneously examine physiological responses (e.g. heart rate and galvanic skin conductance) and subjective behavioural responses to stuttering. The pairing of these objective and subjective data may provide information that casts light on the genesis of negative stereotypes associated with stuttering, the development of compensatory mechanisms in those who stutter, and the true impact of stuttering on senders and receivers alike. To compare the emotional and physiological responses of fluent speakers while listening and observing fluent and severe stuttered speech samples. Twenty adult participants (mean age = 24.15 years, standard deviation = 3.40) observed speech samples of two fluent speakers and two speakers who stutter reading aloud. Participants' skin conductance and heart rate changes were measured as physiological responses to stuttered or fluent speech samples. Participants' subjective responses on arousal (excited-calm) and valence (happy-unhappy) dimensions were assessed via the Self-Assessment Manikin (SAM) rating scale with an additional questionnaire comprised of a set of nine bipolar adjectives. Results showed significantly increased skin conductance and lower mean heart rate during the presentation of stuttered speech relative to the presentation of fluent speech samples (p<0.05). Listeners also self-rated themselves as being more aroused, unhappy, nervous, uncomfortable, sad, tensed, unpleasant, avoiding, embarrassed, and annoyed while viewing stuttered speech relative to the fluent speech. These data support the notion that stutter-filled speech can elicit physiological and emotional responses in listeners. Clinicians who treat stuttering should be aware that listeners show involuntary physiological responses to moderate-severe stuttering that probably remain salient over time and contribute to the evolution of negative stereotypes of people who stutter. With this in mind, it is hoped that clinicians can work with people who stutter to develop appropriate coping strategies. The role of amygdala and mirror neural mechanism in physiological and subjective responses to stuttering is discussed.

  20. CARDS: A blueprint and environment for domain-specific software reuse

    NASA Technical Reports Server (NTRS)

    Wallnau, Kurt C.; Solderitsch, Anne Costa; Smotherman, Catherine

    1992-01-01

    CARDS (Central Archive for Reusable Defense Software) exploits advances in domain analysis and domain modeling to identify, specify, develop, archive, retrieve, understand, and reuse domain-specific software components. An important element of CARDS is to provide visibility into the domain model artifacts produced by, and services provided by, commercial computer-aided software engineering (CASE) technology. The use of commercial CASE technology is important to provide rich, robust support for the varied roles involved in a reuse process. We refer to this kind of use of knowledge representation systems as supporting 'knowledge-based integration.'

  1. Characteristics of stuttering-like disfluencies in Dutch-speaking children.

    PubMed

    Boey, Ronny A; Wuyts, Floris L; Van de Heyning, Paul H; De Bodt, Marc S; Heylen, Louis

    2007-01-01

    The purpose of this study was to compare the characteristics of stuttering-like disfluencies in a group of native Dutch-speaking children who stutter (n=693), with a group of normally fluent children (n=79). Methods involved the observation of stuttering-like disfluencies in participants' conversational speech samples (total 77,200 words), particularly the frequency, duration and physical tension of instances of stuttering. Findings indicate that stuttering-like disfluencies exhibited by children who stutter are significantly more frequent, longer in duration and involve more physical tension when compared to those of normally fluent children. Furthermore, applying a criterion of 3% stuttering-like disfluencies to distinguish stuttering from normally fluent children resulted in a high degree of sensitivity (0.9452) and specificity (0.9747). Results were taken to suggest that characteristics of stuttering-like disfluencies of Dutch-speaking children are similar to those of English-speaking children and that talker group membership criteria for childhood stuttering can reasonably be extrapolated from the Dutch to the English language and vice versa. The reader will be able to: (1) describe characteristics of stuttering-like disfluencies, (2) define properties such as frequency, duration and physical tension for stuttering children and normally fluent children, and (3) make use of data on sensitivity and specificity of the criterion of 3% stuttering-like disfluencies to distinguish stuttering and normally fluent children.

  2. The Main Concept Analysis: Validation and sensitivity in differentiating discourse produced by unimpaired English speakers from individuals with aphasia and dementia of Alzheimer type.

    PubMed

    Kong, Anthony Pak-Hin; Whiteside, Janet; Bargmann, Peggy

    2016-10-01

    Discourse from speakers with dementia and aphasia is associated with comparable but not identical deficits, necessitating appropriate methods to differentiate them. The current study aims to validate the Main Concept Analysis (MCA) to be used for eliciting and quantifying discourse among native typical English speakers and to establish its norm, and investigate the validity and sensitivity of the MCA to compare discourse produced by individuals with fluent aphasia, non-fluent aphasia, or dementia of Alzheimer's type (DAT), and unimpaired elderly. Discourse elicited through a sequential picture description task was collected from 60 unimpaired participants to determine the MCA scoring criteria; 12 speakers with fluent aphasia, 12 with non-fluent aphasia, 13 with DAT, and 20 elderly participants from the healthy group were compared on the finalized MCA. Results of MANOVA revealed significant univariate omnibus effects of speaker group as an independent variable on each main concept index. MCA profiles differed significantly between all participant groups except dementia versus fluent aphasia. Correlations between the MCA performances and the Western Aphasia Battery and Cognitive Linguistic Quick Test were found to be statistically significant among the clinical groups. The MCA was appropriate to be used among native speakers of English. The results also provided further empirical evidence of discourse deficits in aphasia and dementia. Practitioners can use the MCA to evaluate discourse production systemically and objectively.

  3. Commercial Mobile Alert Service (CMAS) Scenarios

    DTIC Science & Technology

    2012-05-01

    Commercial Mobile Alert Service (CMAS) Scenarios The WEA Project Team May 2012 SPECIAL REPORT CMU/SEI-2012-SR-020 CERT® Division, Software ...Homeland Security under Contract No. FA8721-05-C-0003 with Carnegie Mellon University for the operation of the Software Engineering Institute, a federally...DISTRIBUTES IT “AS IS.” References herein to any specific commercial product, process, or service by trade name, trade mark, manufacturer, or otherwise

  4. Influence of Contact Angle Boundary Condition on CFD Simulation of T-Junction

    NASA Astrophysics Data System (ADS)

    Arias, S.; Montlaur, A.

    2018-03-01

    In this work, we study the influence of the contact angle boundary condition on 3D CFD simulations of the bubble generation process occurring in a capillary T-junction. Numerical simulations have been performed with the commercial Computational Fluid Dynamics solver ANSYS Fluent v15.0.7. Experimental results serve as a reference to validate numerical results for four independent parameters: the bubble generation frequency, volume, velocity and length. CFD simulations accurately reproduce experimental results both from qualitative and quantitative points of view. Numerical results are very sensitive to the gas-liquid-wall contact angle boundary conditions, confirming that this is a fundamental parameter to obtain accurate CFD results for simulations of this kind of problems.

  5. Effect of inlet conditions for numerical modelling of the urban boundary layer

    NASA Astrophysics Data System (ADS)

    Gnatowska, Renata

    2018-01-01

    The paper presents the numerical results obtained with the use of the ANSYS FLUENT commercial code for analysing the flow structure around two rectangular inline surface-mounted bluff bodies immersed in a boundary layer. The effects of the inflow boundary layer for the accuracy of the numerical modelling of the flow field around a simple system of objects are described. The analysis was performed for two concepts. In the former case, the inlet velocity profile was defined using the power law, whereas the kinetic and dissipation energy was defined from the equations according to Richards and Hoxey [1]. In the latter case, the inlet conditions were calculated for the flow over the rough area composed of the rectangular components.

  6. Optimization of Wind Turbine Airfoils/Blades and Wind Farm Layouts

    NASA Astrophysics Data System (ADS)

    Chen, Xiaomin

    Shape optimization is widely used in the design of wind turbine blades. In this dissertation, a numerical optimization method called Genetic Algorithm (GA) is applied to address the shape optimization of wind turbine airfoils and blades. In recent years, the airfoil sections with blunt trailing edge (called flatback airfoils) have been proposed for the inboard regions of large wind-turbine blades because they provide several structural and aerodynamic performance advantages. The FX, DU and NACA 64 series airfoils are thick airfoils widely used for wind turbine blade application. They have several advantages in meeting the intrinsic requirements for wind turbines in terms of design point, off-design capabilities and structural properties. This research employ both single- and multi-objective genetic algorithms (SOGA and MOGA) for shape optimization of Flatback, FX, DU and NACA 64 series airfoils to achieve maximum lift and/or maximum lift to drag ratio. The commercially available software FLUENT is employed for calculation of the flow field using the Reynolds-Averaged Navier-Stokes (RANS) equations in conjunction with a two-equation Shear Stress Transport (SST) turbulence model and a three equation k-kl-o turbulence model. The optimization methodology is validated by an optimization study of subsonic and transonic airfoils (NACA0012 and RAE 2822 airfoils). In this dissertation, we employ DU 91-W2-250, FX 66-S196-V1, NACA 64421, and Flat-back series of airfoils (FB-3500-0050, FB-3500-0875, and FB-3500-1750) and compare their performance with S809 airfoil used in NREL Phase II and III wind turbines; the lift and drag coefficient data for these airfoils sections are available. The output power of the turbine is calculated using these airfoil section blades for a given B and lambda and is compared with the original NREL Phase II and Phase III turbines using S809 airfoil section. It is shown that by a suitable choice of airfoil section of HAWT blade, the power generated by the turbine can be significantly increased. Parametric studies are also conducted by varying the turbine diameter. In addition, a simplified dynamic inflow model is integrated into the BEM theory. It is shown that the improved BEM theory has superior performance in capturing the instantaneous behavior of wind turbines due to the existence of wind turbine wake or temporal variations in wind velocity. The dissertation also considers the Wind Farm layout optimization problem using a genetic algorithm. Both the Horizontal --Axis Wind Turbines (HAWT) and Vertical-Axis Wind Turbines (VAWT) are considered. The goal of the optimization problem is to optimally position the turbines within the wind farm such that the wake effects are minimized and the power production is maximized. The reasonably accurate modeling of the turbine wake is critical in determination of the optimal layout of the turbines and the power generated. For HAWT, two wake models are considered; both are found to give similar answers. For VAWT, a very simple wake model is employed. Finally, some preliminary investigation of shape optimization of 3D wind turbine blades at low Reynolds numbers is conducted. The optimization employs a 3D straight untapered wind turbine blade with cross section of NACA 0012 airfoils as the geometry of baseline blade. The optimization objective is to achieve maximum Cl/Cd as well as maximum Cl. The multi-objective genetic algorithm is employed together with the commercially available software FLUENT for calculation of the flow field using the Reynolds-Averaged Navier-Stokes (RANS) equations in conjunction with a one-equation Sparlart-Allmaras turbulence model. The results show excellent performance of the optimized wind turbine blade and indicate the feasibility of optimization on real wind turbine blades with more complex shapes in the future. (Abstract shortened by UMI.)

  7. Determination of current loads of floating platform for special purposes

    NASA Astrophysics Data System (ADS)

    Ma, Guang-ying; Yao, Yun-long; Zhao, Chen-yao

    2017-08-01

    This article studied a new floating offshore platform for special purposes, which was assembled by standard floating modules. The environmental load calculation of the platform is an important part of the research of the ocean platform, which has always been paid attention to by engineers. In addition to wave loads, the wind loads and current loads are also important environmental factors that affect the dynamic response of the offshore platform. The current loads on the bottom structure should not be ignored. By Fluent software, the hydrostatic conditions and external current loads of the platform were calculated in this paper. The coefficient which is independent of the current velocity, namely, current force coefficient, can be fitted through current loads, which can be used for the consequent hydrodynamic and mooring analyses.

  8. Adjoint Airfoil Optimization of Darrieus-Type Vertical Axis Wind Turbine

    NASA Astrophysics Data System (ADS)

    Fuchs, Roman; Nordborg, Henrik

    2012-11-01

    We present the feasibility of using an adjoint solver to optimize the torque of a Darrieus-type vertical axis wind turbine (VAWT). We start with a 2D cross section of a symmetrical airfoil and restrict us to low solidity ratios to minimize blade vortex interactions. The adjoint solver of the ANSYS FLUENT software package computes the sensitivities of airfoil surface forces based on a steady flow field. Hence, we find the torque of a full revolution using a weighted average of the sensitivities at different wind speeds and angles of attack. The weights are computed analytically, and the range of angles of attack is given by the tip speed ratio. Then the airfoil geometry is evolved, and the proposed methodology is evaluated by transient simulations.

  9. Numerical simulation of air distribution in a room with a sidewall jet under benchmark test conditions

    NASA Astrophysics Data System (ADS)

    Zasimova, Marina; Ivanov, Nikolay

    2018-05-01

    The goal of the study is to validate Large Eddy Simulation (LES) data on mixing ventilation in an isothermal room at conditions of benchmark experiments by Hurnik et al. (2015). The focus is on the accuracy of the mean and rms velocity fields prediction in the quasi-free jet zone of the room with 3D jet supplied from a sidewall rectangular diffuser. Calculations were carried out using the ANSYS Fluent 16.2 software with an algebraic wall-modeled LES subgrid-scale model. CFD results on the mean velocity vector are compared with the Laser Doppler Anemometry data. The difference between the mean velocity vector and the mean air speed in the jet zone, both LES-computed, is presented and discussed.

  10. CFD Prediction on the Pressure Distribution and Streamlines around an Isolated Single-Storey House Considering the Effect of Topographic Characteristics

    NASA Astrophysics Data System (ADS)

    Abdullah, J.; Zaini, S. S.; Aziz, M. S. A.; Majid, T. A.; Deraman, S. N. C.; Yahya, W. N. W.

    2018-04-01

    Single-storey houses are classified as low rise building and vulnerable to damages under windstorm event. This study was carried out with the aim to investigate the pressure distribution and streamlines around an isolated house by considering the effect of terrain characteristics. The topographic features such as flat, depression, ridge, and valley, are considered in this study. This simulation were analysed with Ansys FLUENT 14.0 software package. The result showed the topography characteristics influence the value of pressure coefficient and streamlines especially when the house was located at ridge terrain. The findings strongly suggested that wind analysis should include all topographic features in the analysis in order to establish the true wind force exerted on any structure.

  11. Three dimensional investigation of the shock train structure in a convergent-divergent nozzle

    NASA Astrophysics Data System (ADS)

    Mousavi, Seyed Mahmood; Roohi, Ehsan

    2014-12-01

    Three-dimensional computational fluid dynamics analyses have been employed to study the compressible and turbulent flow of the shock train in a convergent-divergent nozzle. The primary goal is to determine the behavior, location, and number of shocks. In this context, full multi-grid initialization, Reynolds stress turbulence model (RSM), and the grid adaption techniques in the Fluent software are utilized under the 3D investigation. The results showed that RSM solution matches with the experimental data suitably. The effects of applying heat generation sources and changing inlet flow total temperature have been investigated. Our simulations showed that changes in the heat generation rate and total temperature of the intake flow influence on the starting point of shock, shock strength, minimum pressure, as well as the maximum flow Mach number.

  12. 48 CFR 208.7400 - Scope of subpart.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... OF DEFENSE ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Enterprise Software... commercial software and software maintenance, including software and software maintenance that is acquired— (a) As part of a system or system upgrade, where practicable; (b) Under a service contract; (c) Under...

  13. Common Data Acquisition Systems (DAS) Software Development for Rocket Propulsion Test (RPT) Test Facilities - A General Overview

    NASA Technical Reports Server (NTRS)

    Hebert, Phillip W., Sr.; Hughes, Mark S.; Davis, Dawn M.; Turowski, Mark P.; Holladay, Wendy T.; Marshall, PeggL.; Duncan, Michael E.; Morris, Jon A.; Franzl, Richard W.

    2012-01-01

    The advent of the commercial space launch industry and NASA's more recent resumption of operation of Stennis Space Center's large test facilities after thirty years of contractor control resulted in a need for a non-proprietary data acquisition system (DAS) software to support government and commercial testing. The software is designed for modularity and adaptability to minimize the software development effort for current and future data systems. An additional benefit of the software's architecture is its ability to easily migrate to other testing facilities thus providing future commonality across Stennis. Adapting the software to other Rocket Propulsion Test (RPT) Centers such as MSFC, White Sands, and Plumbrook Station would provide additional commonality and help reduce testing costs for NASA. Ultimately, the software provides the government with unlimited rights and guarantees privacy of data to commercial entities. The project engaged all RPT Centers and NASA's Independent Verification & Validation facility to enhance product quality. The design consists of a translation layer which provides the transparency of the software application layers to underlying hardware regardless of test facility location and a flexible and easily accessible database. This presentation addresses system technical design, issues encountered, and the status of Stennis' development and deployment.

  14. Air Force and the Cyberspace Mission: Defending the Air Force’s Computer Network in the Future

    DTIC Science & Technology

    2007-12-01

    computers, their operating systems and software purchased by the Air Force are commercial off-the-shelf (COTS) components, often manufactured abroad due...crystal clear 2003 information security report: “The U.S. Department of Defense (DOD) relies too much on commercial software , doesn’t know who is...creating the software , and faces other significant cybersecurity problems.”11 This paper explores the topic of defense of the cyberspace domain by

  15. Interactive reconstructions of cranial 3D implants under MeVisLab as an alternative to commercial planning software.

    PubMed

    Egger, Jan; Gall, Markus; Tax, Alois; Ücal, Muammer; Zefferer, Ulrike; Li, Xing; von Campe, Gord; Schäfer, Ute; Schmalstieg, Dieter; Chen, Xiaojun

    2017-01-01

    In this publication, the interactive planning and reconstruction of cranial 3D Implants under the medical prototyping platform MeVisLab as alternative to commercial planning software is introduced. In doing so, a MeVisLab prototype consisting of a customized data-flow network and an own C++ module was set up. As a result, the Computer-Aided Design (CAD) software prototype guides a user through the whole workflow to generate an implant. Therefore, the workflow begins with loading and mirroring the patients head for an initial curvature of the implant. Then, the user can perform an additional Laplacian smoothing, followed by a Delaunay triangulation. The result is an aesthetic looking and well-fitting 3D implant, which can be stored in a CAD file format, e.g. STereoLithography (STL), for 3D printing. The 3D printed implant can finally be used for an in-depth pre-surgical evaluation or even as a real implant for the patient. In a nutshell, our research and development shows that a customized MeVisLab software prototype can be used as an alternative to complex commercial planning software, which may also not be available in every clinic. Finally, not to conform ourselves directly to available commercial software and look for other options that might improve the workflow.

  16. Interactive reconstructions of cranial 3D implants under MeVisLab as an alternative to commercial planning software

    PubMed Central

    Egger, Jan; Gall, Markus; Tax, Alois; Ücal, Muammer; Zefferer, Ulrike; Li, Xing; von Campe, Gord; Schäfer, Ute; Schmalstieg, Dieter; Chen, Xiaojun

    2017-01-01

    In this publication, the interactive planning and reconstruction of cranial 3D Implants under the medical prototyping platform MeVisLab as alternative to commercial planning software is introduced. In doing so, a MeVisLab prototype consisting of a customized data-flow network and an own C++ module was set up. As a result, the Computer-Aided Design (CAD) software prototype guides a user through the whole workflow to generate an implant. Therefore, the workflow begins with loading and mirroring the patients head for an initial curvature of the implant. Then, the user can perform an additional Laplacian smoothing, followed by a Delaunay triangulation. The result is an aesthetic looking and well-fitting 3D implant, which can be stored in a CAD file format, e.g. STereoLithography (STL), for 3D printing. The 3D printed implant can finally be used for an in-depth pre-surgical evaluation or even as a real implant for the patient. In a nutshell, our research and development shows that a customized MeVisLab software prototype can be used as an alternative to complex commercial planning software, which may also not be available in every clinic. Finally, not to conform ourselves directly to available commercial software and look for other options that might improve the workflow. PMID:28264062

  17. /S/ Variation as Accommodation.

    ERIC Educational Resources Information Center

    Coles, Felice Anne

    1993-01-01

    The few remaining fluent speakers of the isleno dialect of Spanish vary their casual pronunciation of /s/ in a manner consistent with, but not identical to, other Caribbean Spanish dialects. The behavior of /s/ in the speech of nonfluent islenos parallels that of fluent speakers, differing only in the higher degree of aspiration and deletion. This…

  18. The Effect of Rhythmic Auditory Stimulation on the Disfluency of Nonstutterers

    ERIC Educational Resources Information Center

    Silverman, Franklin H.

    1971-01-01

    Twenty adult male nonstutterers became more fluent when pacing their speech with a metronome. The degree to which they became more fluent was within the range which has been reported for stutterers. This finding suggests that the effect of the metronome on stuttering is not primarily a result of distraction. (Author/KW)

  19. Reclassification of English Learner Students in California. Technical Appendices

    ERIC Educational Resources Information Center

    Hill, Laura E.; Weston, Margaret; Hayes, Joseph M.

    2014-01-01

    Former English Learner students who have improved their facility with English to such a degree that they have been reclassified by their school districts as fluent in the English language are among the best performing students in the state. Because these Reclassified Fluent English Proficient (RFEP) students have much better academic outcomes than…

  20. Reclassification of English Learner Students in California

    ERIC Educational Resources Information Center

    Hill, Laura E.; Weston, Margaret; Hayes, Joseph M.

    2014-01-01

    Former English Learner students who have improved their facility with English to such a degree that they have been reclassified by their school districts as fluent in the English language are among the best performing students in the state. Because these Reclassified Fluent English Proficient (RFEP) students have much better academic outcomes than…

  1. Extending Interactive Writing into Grades 2-5

    ERIC Educational Resources Information Center

    Roth, Kate; Dabrowski, Joan

    2014-01-01

    Interactive writing is an instructional practice widely considered effective and most appropriate for emergent writers. This article asserts that it is a valuable method for more fluent writers in grades 2-5. It outlines the basic lesson sequence and proposes four key shifts to adapt interactive writing for older, more fluent writers: 1) The…

  2. Coordination of Oral and Laryngeal Movements in the Perceptually Fluent Speech of Adults Who Stutter

    ERIC Educational Resources Information Center

    Max, Ludo; Gracco, Vincent L.

    2005-01-01

    This work investigated whether stuttering and nonstuttering adults differ in the coordination of oral and laryngeal movements during the production of perceptually fluent speech. This question was addressed by completing correlation analyses that extended previous acoustic studies by others as well as inferential analyses based on the…

  3. Speech Errors in Progressive Non-Fluent Aphasia

    ERIC Educational Resources Information Center

    Ash, Sharon; McMillan, Corey; Gunawardena, Delani; Avants, Brian; Morgan, Brianna; Khan, Alea; Moore, Peachie; Gee, James; Grossman, Murray

    2010-01-01

    The nature and frequency of speech production errors in neurodegenerative disease have not previously been precisely quantified. In the present study, 16 patients with a progressive form of non-fluent aphasia (PNFA) were asked to tell a story from a wordless children's picture book. Errors in production were classified as either phonemic,…

  4. Modulation of N400 in Chronic Non-Fluent Aphasia Using Low Frequency Repetitive Transcranial Magnetic Stimulation (rTMS)

    ERIC Educational Resources Information Center

    Barwood, Caroline H. S.; Murdoch, Bruce E.; Whelan, Brooke-Mai; Lloyd, David; Riek, Stephan; O'Sullivan, John D.; Coulthard, Alan; Wong, Andrew

    2011-01-01

    Low frequency Repetitive Transcranial Magnetic Stimulation (rTMS) has previously been applied to language homologues in non-fluent populations of persons with aphasia yielding significant improvements in behavioral language function up to 43 months post stimulation. The present study aimed to investigate the electrophysiological correlates…

  5. Differences of Articulation Rate and Utterance Length in Fluent and Disfluent Utterances of Preschool Children Who Stutter

    ERIC Educational Resources Information Center

    Chon, HeeCheong; Sawyer, Jean; Ambrose, Nicoline G.

    2012-01-01

    Purpose: The purpose of this study was to investigate characteristics of four types of utterances in preschool children who stutter: perceptually fluent, containing normal disfluencies (OD utterance), containing stuttering-like disfluencies (SLD utterance), and containing both normal and stuttering-like disfluencies (SLD+OD utterance).…

  6. Under Construction: Minority Girls Becoming Technologically Fluent in an Urban After-School Program

    ERIC Educational Resources Information Center

    De La Pena, Yvonne

    2012-01-01

    Technological fluency involves having a deep understanding of information technology as well as an identity as someone who engages with technology in meaningful and complex ways. Hence, it is more fruitful to think about individuals not as developing technological fluency but rather as becoming technologically fluent. Although physical access to…

  7. A Fluent Language Disorder Following Antepartum Left-Hemisphere Brain Injury.

    ERIC Educational Resources Information Center

    Feldman, Heidi M.; And Others

    1992-01-01

    This article describes the language development in a left-handed young child with a left middle cerebral artery infarction. Patterns of development observed between 36 and 60 months of age are described as a transient jargon or fluent aphasia possibly resulting from initial reliance on an uninjured right hemisphere. (Author/DB)

  8. Analysis of oral narratives of children who stutter and their fluent peers: kindergarten through second grade.

    PubMed

    Bajaj, Amit

    2007-03-01

    Measures of language sample length (in c-units) and morphological, syntactic, and narrative abilities were obtained from oral narrative transcripts of 22 children who stutter and 22 children who do not stutter; participants attended kindergarten, first, and second grades. A two-way MANOVA yielded significant main effects for grade, with significant differences on some measures evidenced between participants in kindergarten and second grades. No significant differences between groups or group-grade interaction effects on the measures were obtained. Grade-wise comparisons (through t-tests) indicated that the performance of children who stutter did not differ significantly from their typically fluent peers on all dependent measures; however, kindergarten children who stutter obtained the most discrepant (lower) scores than their grade-matched fluent peers on the Narrative Scoring Scheme measure, with group differences approaching statistical significance on this measure. The findings suggest that children who do and do not stutter evidence similar expressive language abilities, even as subgroups of children who stutter may lag behind their grade-matched fluent peers in particular language domains.

  9. Deep dysphasic performance in non-fluent progressive aphasia: a case study.

    PubMed

    Tree, J J; Perfect, T J; Hirsh, K W; Copstick, S

    2001-01-01

    We present a patient (PW) with non-fluent progressive aphasia, characterized by severe word finding difficulties and frequent phonemic paraphasias in spontaneous speech. It has been suggested that such patients have insufficient access to phonological information for output and cannot construct the appropriate sequence of selected phonemes for articulation. Consistent with such a proposal, we found that PW was impaired on a variety of verbal tasks that demand access to phonological representations (reading, repetition, confrontational naming and rhyme judgement); she also demonstrated poor performance on syntactic and grammatical processing tasks. However, examination of PW's repetition performance also revealed that she made semantic paraphasias and that her performance was influenced by imageability and lexical status. Her auditory-verbal short-term memory was also severely compromised. These features are consistent with 'deep dysphasia', a disorder reported in patients suffering from stroke or cerebrovascular accident, and rarely reported in the context of non-fluent progressive aphasia. PW's pattern of performance is evaluated in terms of current models of both non-fluent progressive aphasia and deep dysphasia.

  10. Numerical simulation of turbulent forced convection in liquid metals

    NASA Astrophysics Data System (ADS)

    Vodret, S.; Vitale Di Maio, D.; Caruso, G.

    2014-11-01

    In the frame of the future generation of nuclear reactors, liquid metals are foreseen to be used as a primary coolant. Liquid metals are characterized by a very low Prandtl number due to their very high heat diffusivity. As such, they do not meet the so-called Reynolds analogy which assumes a complete similarity between the momentum and the thermal boundary layers via the use of the turbulent Prandtl number. Particularly, in the case of industrial fluid-dynamic calculations where a resolved computation near walls could be extremely time consuming and could need very large computational resources, the use of the classical wall function approach could lead to an inaccurate description of the temperature profile close to the wall. The first aim of the present study is to investigate the ability of a well- established commercial code (ANSYS FLUENT v.14) to deal with this issue, validating a suitable expression for the turbulent Prandtl number. Moreover, a thermal wall-function developed at Universite Catholique de Louvain has been implemented in FLUENT and validated, overcoming the limits of the solver to define it directly. Both the resolved and unresolved approaches have been carried out for a channel flow case and assessed against available direct numerical and large eddy simulations. A comparison between the numerically evaluated Nusselt number and the main correlations available in the literature has been also carried out. Finally, an application of the proposed methodology to a typical sub-channel case has been performed, comparing the results with literature correlations for tube banks.

  11. Rethinking covert stuttering.

    PubMed

    Constantino, Christopher Dominick; Manning, Walter H; Nordstrom, Susan Naomi

    2017-09-01

    The experience of passing as fluent, also called covert stuttering, has been uncritically framed as an inherently negative pursuit. Historically passing has been understood as a repression of one's true, authentic self in response to either psychological distress or social discrimination. The authors of this paper seek a more nuanced understanding of passing. We ask, how must a person relate to herself in order to pass as fluent? This is a qualitative research study in which the authors utilized the ethical theories of philosopher Michel Foucault to contextualize data obtained from semi-structured interviews with nine participants who pass as fluent. Rather than a repression of an authentic self our data suggests passing is more usefully understood as a form of resistance by people who stutter to a hostile society. Participants learned from experiences of delegitimization that their stuttering had ethical ramifications. Consequently, they used a variety of self-forming practices to pass and thereby achieve the privileges that come with perceived able-bodiedness. Passing as fluent is not an inauthentic form of stuttering but a form of stuttering that is produced through the use of specific technologies of communication. These technologies of communication are constituted by the unique ethical relationship of the person who stutters with herself. Passing can be understood as an active form of resistance rather than a passive form of repression. By theorizing passing as fluent as an ethical relationship, we open up the possibility of changing the relationship and performing it differently. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Development of a Cross-Flow Fan Rotor for Vertical Take-Off and Landing Aircraft

    DTIC Science & Technology

    2013-06-01

    ANSYS CFX , along with the commercial computer-aided design software SolidWorks, was used to model and perform a parametric study on the number of rotor...the results found using ANSYS CFX . The experimental and analytical models were successfully compared at speeds ranging from 4,000 to 7,000 RPM...will make vertical take-off possible. The commercial computational fluid dynamics software ANSYS CFX , along with the commercial computer-aided design

  13. The trouble with nouns and verbs in Greek fluent aphasia.

    PubMed

    Kambanaros, Maria

    2008-01-01

    In the past verb retrieval problems were associated primarily with agrammatism and noun retrieval difficulties with fluent aphasia. With regards to fluent aphasia, so far in the literature, three distinct patterns of verb/noun dissociations have been described for individuals with fluent anomic aphasia in languages with different underlying forms; better verb retrieval, poorer verb retrieval and equal retrieval difficulties for verbs and nouns. Verbs and nouns in Greek are considered of similar morphological complexity thus it was predicted that anomic aphasic individuals would suffer from a non-dissociated impairment of verbs and nouns. Problems with verbs and/or nouns may arise at any stage in the process of lexical retrieval, i.e. lexical-semantic, lemma, lexeme or articulation. The aim of this research was to investigate verb and noun retrieval using a picture-naming task to explore any possible selective noun and/or verb comprehension or retrieval deficits in Greek individuals with anomic aphasia. The results revealed a significant verb/noun dichotomy with verbs significantly more difficult to retrieve than nouns. These findings lend support for the growing body of evidence showing a specific verb impairment in fluent anomic individuals as well as Broca's patients. Given the prevailing view, that anomic patients experience difficulty retrieving the morpho-phonological form of the target word, the results show that specific information of the grammatical category is also important during word form retrieval. LEARNER OUTCOMES: The reader will become familiar with (i) studies investigating grammatical word class breakdown in individuals with aphasia who speak different languages, (ii) the application of the serial model to word production breakdown in aphasia and (iii) the characteristics of verbs and nouns in Greek. It will be concluded that successful verb retrieval for fluent aphasic individuals who speak Greek is dependant on the retrieval of the morpho-phonological information of the target verb.

  14. 48 CFR 208.7402 - General.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... DEFENSE ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Enterprise Software Agreements 208.7402 General. Departments and agencies shall fulfill requirements for commercial software and related services, such as software maintenance, in accordance with the DoD Enterprise Software Initiative (ESI...

  15. 48 CFR 208.7402 - General.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... DEFENSE ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Enterprise Software Agreements 208.7402 General. (1) Departments and agencies shall fulfill requirements for commercial software and related services, such as software maintenance, in accordance with the DoD Enterprise Software Initiative...

  16. 48 CFR 208.7402 - General.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... DEFENSE ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Enterprise Software Agreements 208.7402 General. Departments and agencies shall fulfill requirements for commercial software and related services, such as software maintenance, in accordance with the DoD Enterprise Software Initiative (ESI...

  17. 48 CFR 208.7402 - General.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... DEFENSE ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Enterprise Software Agreements 208.7402 General. Departments and agencies shall fulfill requirements for commercial software and related services, such as software maintenance, in accordance with the DoD Enterprise Software Initiative (ESI...

  18. 48 CFR 208.7401 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... OF DEFENSE ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Enterprise Software... a contract that is used to acquire designated commercial software or related services such as... Officer to develop processes for DoD-wide software asset management. Software maintenance means services...

  19. Formant transitions in the fluent speech of Farsi-speaking people who stutter.

    PubMed

    Dehqan, Ali; Yadegari, Fariba; Blomgren, Michael; Scherer, Ronald C

    2016-06-01

    Second formant (F2) transitions can be used to infer attributes of articulatory transitions. This study compared formant transitions during fluent speech segments of Farsi (Persian) speaking people who stutter and normally fluent Farsi speakers. Ten Iranian males who stutter and 10 normally fluent Iranian males participated. Sixteen different "CVt" tokens were embedded within the phrase "Begu CVt an". Measures included overall F2 transition frequency extents, durations, and derived overall slopes, initial F2 transition slopes at 30ms and 60ms, and speaking rate. (1) Mean overall formant frequency extent was significantly greater in 14 of the 16 CVt tokens for the group of stuttering speakers. (2) Stuttering speakers exhibited significantly longer overall F2 transitions for all 16 tokens compared to the nonstuttering speakers. (3) The overall F2 slopes were similar between the two groups. (4) The stuttering speakers exhibited significantly greater initial F2 transition slopes (positive or negative) for five of the 16 tokens at 30ms and six of the 16 tokens at 60ms. (5) The stuttering group produced a slower syllable rate than the non-stuttering group. During perceptually fluent utterances, the stuttering speakers had greater F2 frequency extents during transitions, took longer to reach vowel steady state, exhibited some evidence of steeper slopes at the beginning of transitions, had overall similar F2 formant slopes, and had slower speaking rates compared to nonstuttering speakers. Findings support the notion of different speech motor timing strategies in stuttering speakers. Findings are likely to be independent of the language spoken. Educational objectives This study compares aspects of F2 formant transitions between 10 stuttering and 10 nonstuttering speakers. Readers will be able to describe: (a) characteristics of formant frequency as a specific acoustic feature used to infer speech movements in stuttering and nonstuttering speakers, (b) two methods of measuring second formant (F2) transitions: the visual criteria method and fixed time criteria method, (c) characteristics of F2 transitions in the fluent speech of stuttering speakers and how those characteristics appear to differ from normally fluent speakers, and (d) possible cross-linguistic effects on acoustic analyses of stuttering. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Damage to the anterior arcuate fasciculus predicts non-fluent speech production in aphasia.

    PubMed

    Fridriksson, Julius; Guo, Dazhou; Fillmore, Paul; Holland, Audrey; Rorden, Chris

    2013-11-01

    Non-fluent aphasia implies a relatively straightforward neurological condition characterized by limited speech output. However, it is an umbrella term for different underlying impairments affecting speech production. Several studies have sought the critical lesion location that gives rise to non-fluent aphasia. The results have been mixed but typically implicate anterior cortical regions such as Broca's area, the left anterior insula, and deep white matter regions. To provide a clearer picture of cortical damage in non-fluent aphasia, the current study examined brain damage that negatively influences speech fluency in patients with aphasia. It controlled for some basic speech and language comprehension factors in order to better isolate the contribution of different mechanisms to fluency, or its lack. Cortical damage was related to overall speech fluency, as estimated by clinical judgements using the Western Aphasia Battery speech fluency scale, diadochokinetic rate, rudimentary auditory language comprehension, and executive functioning (scores on a matrix reasoning test) in 64 patients with chronic left hemisphere stroke. A region of interest analysis that included brain regions typically implicated in speech and language processing revealed that non-fluency in aphasia is primarily predicted by damage to the anterior segment of the left arcuate fasciculus. An improved prediction model also included the left uncinate fasciculus, a white matter tract connecting the middle and anterior temporal lobe with frontal lobe regions, including the pars triangularis. Models that controlled for diadochokinetic rate, picture-word recognition, or executive functioning also revealed a strong relationship between anterior segment involvement and speech fluency. Whole brain analyses corroborated the findings from the region of interest analyses. An additional exploratory analysis revealed that involvement of the uncinate fasciculus adjudicated between Broca's and global aphasia, the two most common kinds of non-fluent aphasia. In summary, the current results suggest that the anterior segment of the left arcuate fasciculus, a white matter tract that lies deep to posterior portions of Broca's area and the sensory-motor cortex, is a robust predictor of impaired speech fluency in aphasic patients, even when motor speech, lexical processing, and executive functioning are included as co-factors. Simply put, damage to those regions results in non-fluent aphasic speech; when they are undamaged, fluent aphasias result.

  1. Damage to the anterior arcuate fasciculus predicts non-fluent speech production in aphasia

    PubMed Central

    Guo, Dazhou; Fillmore, Paul; Holland, Audrey; Rorden, Chris

    2013-01-01

    Non-fluent aphasia implies a relatively straightforward neurological condition characterized by limited speech output. However, it is an umbrella term for different underlying impairments affecting speech production. Several studies have sought the critical lesion location that gives rise to non-fluent aphasia. The results have been mixed but typically implicate anterior cortical regions such as Broca’s area, the left anterior insula, and deep white matter regions. To provide a clearer picture of cortical damage in non-fluent aphasia, the current study examined brain damage that negatively influences speech fluency in patients with aphasia. It controlled for some basic speech and language comprehension factors in order to better isolate the contribution of different mechanisms to fluency, or its lack. Cortical damage was related to overall speech fluency, as estimated by clinical judgements using the Western Aphasia Battery speech fluency scale, diadochokinetic rate, rudimentary auditory language comprehension, and executive functioning (scores on a matrix reasoning test) in 64 patients with chronic left hemisphere stroke. A region of interest analysis that included brain regions typically implicated in speech and language processing revealed that non-fluency in aphasia is primarily predicted by damage to the anterior segment of the left arcuate fasciculus. An improved prediction model also included the left uncinate fasciculus, a white matter tract connecting the middle and anterior temporal lobe with frontal lobe regions, including the pars triangularis. Models that controlled for diadochokinetic rate, picture-word recognition, or executive functioning also revealed a strong relationship between anterior segment involvement and speech fluency. Whole brain analyses corroborated the findings from the region of interest analyses. An additional exploratory analysis revealed that involvement of the uncinate fasciculus adjudicated between Broca’s and global aphasia, the two most common kinds of non-fluent aphasia. In summary, the current results suggest that the anterior segment of the left arcuate fasciculus, a white matter tract that lies deep to posterior portions of Broca’s area and the sensory-motor cortex, is a robust predictor of impaired speech fluency in aphasic patients, even when motor speech, lexical processing, and executive functioning are included as co-factors. Simply put, damage to those regions results in non-fluent aphasic speech; when they are undamaged, fluent aphasias result. PMID:24131592

  2. Perceptions of Open Source versus Commercial Software: Is Higher Education Still on the Fence?

    ERIC Educational Resources Information Center

    van Rooij, Shahron Williams

    2007-01-01

    This exploratory study investigated the perceptions of technology and academic decision-makers about open source benefits and risks versus commercial software applications. The study also explored reactions to a concept for outsourcing campus-wide deployment and maintenance of open source. Data collected from telephone interviews were analyzed,…

  3. The Relationship between Transformational and Transactional Leadership Styles and Innovation Commitment and Output at Commercial Software Companies

    ERIC Educational Resources Information Center

    Golla, Eric James

    2012-01-01

    The purpose of this quantitative study was to discover whether relationships exist between leadership styles and innovation commitment and innovation output at commercial software companies. The leadership styles included transformational and transactional, and the innovation variables included (a) the percentage of expenses allocated to…

  4. A USNRC perspective on the use of commercial-off-shelf software (COTS) in advanced reactors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stewart, J.C.

    1997-12-01

    The use of commercially available digital computer systems and components in safety critical systems (nuclear power plant, military, and commercial applications) is increasing rapidly. While this paper focuses on the software aspects of the application most of these continents are applicable to the hardware aspects as well. Commercial dedication (the process of assuring that a commercial grade item will perform its intended safety function) has demonstrated benefits in cost savings and a wide base of user experience, however, care must be taken to avoid difficulties with some aspects of the dedication process such as access to vendor development information, configurationmore » management long term support, and system integration.« less

  5. Towards integration of clinical decision support in commercial hospital information systems using distributed, reusable software and knowledge components.

    PubMed

    Müller, M L; Ganslandt, T; Eich, H P; Lang, K; Ohmann, C; Prokosch, H U

    2001-12-01

    Clinicians' acceptance of clinical decision support depends on its workflow-oriented, context-sensitive accessibility and availability at the point of care, integrated into the Electronic Patient Record (EPR). Commercially available Hospital Information Systems (HIS) often focus on administrative tasks and mostly do not provide additional knowledge based functionality. Their traditionally monolithic and closed software architecture encumbers integration of and interaction with external software modules. Our aim was to develop methods and interfaces to integrate knowledge sources into two different commercial hospital information systems to provide the best decision support possible within the context of available patient data. An existing, proven standalone scoring system for acute abdominal pain was supplemented by a communication interface. In both HIS we defined data entry forms and developed individual and reusable mechanisms for data exchange with external software modules. We designed an additional knowledge support frontend which controls data exchange between HIS and the knowledge modules. Finally, we added guidelines and algorithms to the knowledge library. Despite some major drawbacks which resulted mainly from the HIS' closed software architectures we showed exemplary, how external knowledge support can be integrated almost seamlessly into different commercial HIS. This paper describes the prototypical design and current implementation and discusses our experiences.

  6. Commercial Literacy Software.

    ERIC Educational Resources Information Center

    Balajthy, Ernest

    1997-01-01

    Presents the first year's results of a continuing project to monitor the availability of software of relevance for literacy education purposes. Concludes there is an enormous amount of software available for use by teachers of reading and literacy--whereas drill-and-practice software is the largest category of software available, large numbers of…

  7. Communicative Ability Conceptions among Children Who Stutter and Their Fluent Peers: A Qualitative Exploration

    ERIC Educational Resources Information Center

    Bajaj, Amit; Hodson, Barbara; Westby, Carol

    2005-01-01

    Meta issues in stuttering were examined by analyzing verbal-descriptive data drawn from structured interviews with 23 male children who stutter (CWS) and their 23 fluent male peers. Participants described others' "good" and "bad" talk behaviors and provided their self-appraisals as talkers. Analysis of interview transcripts suggested that CWS…

  8. Assisting a Struggling Turkish Student with a Repeated Reading Fluency Intervention

    ERIC Educational Resources Information Center

    Yildirim, Kasim; Ritz, Elizabeth; Akyol, Hayati; Rasinski, Timothy

    2015-01-01

    One of the most important aims of teaching reading is to help students acquire fluent reading skills. With this aim in mind, this study attempted to support a student with difficulty to become a fluent reader by improving his reading skills using a fluency instruction method called repeated reading. This study was performed with an elementary…

  9. Making English Learner Reclassification to Fluent English Proficient Attainable or Elusive: When Meeting Criteria Is and Is "Not" Enough

    ERIC Educational Resources Information Center

    Estrada, Peggy; Wang, Haiwen

    2018-01-01

    Employing longitudinal, multisite comparative mixed-methods, we describe patterns of reclassifying and not reclassifying eligible English learner (EL) students to fluent English proficient, and we identify factors impeding and facilitating reclassification. Analyses of administrative data for 7 cohorts of students over 3 years in one district and…

  10. A Comparison of Coverbal Gesture Use in Oral Discourse among Speakers with Fluent and Nonfluent Aphasia

    ERIC Educational Resources Information Center

    Kong, Anthony Pak-Hin; Law, Sam-Po; Chak, Gigi Wan-Chi

    2017-01-01

    Purpose: Coverbal gesture use, which is affected by the presence and degree of aphasia, can be culturally specific. The purpose of this study was to compare gesture use among Cantonese-speaking individuals: 23 neurologically healthy speakers, 23 speakers with fluent aphasia, and 21 speakers with nonfluent aphasia. Method: Multimedia data of…

  11. Individual Variability in Delayed Auditory Feedback Effects on Speech Fluency and Rate in Normally Fluent Adults

    ERIC Educational Resources Information Center

    Chon, HeeCheong; Kraft, Shelly Jo; Zhang, Jingfei; Loucks, Torrey; Ambrose, Nicoline G.

    2013-01-01

    Purpose: Delayed auditory feedback (DAF) is known to induce stuttering-like disfluencies (SLDs) and cause speech rate reductions in normally fluent adults, but the reason for speech disruptions is not fully known, and individual variation has not been well characterized. Studying individual variation in susceptibility to DAF may identify factors…

  12. Poetry: A Feast to Form Fluent Readers.

    ERIC Educational Resources Information Center

    Seitz, Sheila

    In this lesson plan, grade 3 to 5 students examine elements of fluent reading through oral poetry performance. They use the Internet to identify a poem to prepare and perform for the class. The main objective of this lesson concerns improving fluency. During four hours over a span of five days, students will: be able to identify text written in…

  13. Early-Stage Chunking of Finger Tapping Sequences by Persons Who Stutter and Fluent Speakers

    ERIC Educational Resources Information Center

    Smits-Bandstra, Sarah; De Nil, Luc F.

    2013-01-01

    This research note explored the hypothesis that chunking differences underlie the slow finger-tap sequencing performance reported in the literature for persons who stutter (PWS) relative to fluent speakers (PNS). Early-stage chunking was defined as an immediate and spontaneous tendency to organize a long sequence into pauses, for motor planning,…

  14. Autonomic and Emotional Responses of Graduate Student Clinicians in Speech-Language Pathology to Stuttered Speech

    ERIC Educational Resources Information Center

    Guntupalli, Vijaya K.; Nanjundeswaran, Chayadevie; Dayalu, Vikram N.; Kalinowski, Joseph

    2012-01-01

    Background: Fluent speakers and people who stutter manifest alterations in autonomic and emotional responses as they view stuttered relative to fluent speech samples. These reactions are indicative of an aroused autonomic state and are hypothesized to be triggered by the abrupt breakdown in fluency exemplified in stuttered speech. Furthermore,…

  15. Phonation Interval Modification and Speech Performance Quality during Fluency-Inducing Conditions by Adults Who Stutter

    ERIC Educational Resources Information Center

    Ingham, Roger J.; Bothe, Anne K.; Wang, Yuedong; Purkhiser, Krystal; New, Anneliese

    2012-01-01

    Purpose: To relate changes in four variables previously defined as characteristic of normally fluent speech to changes in phonatory behavior during oral reading by persons who stutter (PWS) and normally fluent controls under multiple fluency-inducing (FI) conditions. Method: Twelve PWS and 12 controls each completed 4 ABA experiments. During A…

  16. The Ruggedized STD Bus Microcomputer - A low cost computer suitable for Space Shuttle experiments

    NASA Technical Reports Server (NTRS)

    Budney, T. J.; Stone, R. W.

    1982-01-01

    Previous space flight computers have been costly in terms of both hardware and software. The Ruggedized STD Bus Microcomputer is based on the commercial Mostek/Pro-Log STD Bus. Ruggedized PC cards can be based on commercial cards from more than 60 manufacturers, reducing hardware cost and design time. Software costs are minimized by using standard 8-bit microprocessors and by debugging code using commercial versions of the ruggedized flight boards while the flight hardware is being fabricated.

  17. Evaluation of MTANNs for eliminating false-positive with different computer aided pulmonary nodules detection software.

    PubMed

    Shi, Zhenghao; Ma, Jiejue; Feng, Yaning; He, Lifeng; Suzuki, Kenji

    2015-11-01

    MTANN (Massive Training Artificial Neural Network) is a promising tool, which applied to eliminate false-positive for thoracic CT in recent years. In order to evaluate whether this method is feasible to eliminate false-positive of different CAD schemes, especially, when it is applied to commercial CAD software, this paper evaluate the performance of the method for eliminating false-positives produced by three different versions of commercial CAD software for lung nodules detection in chest radiographs. Experimental results demonstrate that the approach is useful in reducing FPs for different computer aided lung nodules detection software in chest radiographs.

  18. Modeling of milk flow in mammary ducts in lactating human female breast.

    PubMed

    Mortazavi, S Negin; Geddes, Donna; Hassanipour, Fatemeh

    2014-01-01

    A transient laminar Newtonian three-dimensional CFD simulation has been studied for milk flow in a phantom model of the 6-generations human lactating breast branching system. Milk is extracted by the cyclic pattern of suction from the alveoli through the duct and to the nipple. The real negative (suction) pressure data are applied as an outlet boundary condition in nipple. In this study, the commercial CFD code (Fluent Inc., 2004) is employed for the numerical solution of the milk flow. The milk intake flow rate from simulation is compared to the real clinical data from published paper. The results are in good agreement. It is believed that the methodology of the lactating human breast branching modeling proposed here can provide potential guidelines for further clinical and research application.

  19. Numerical simulation of pressure fluctuation in 1000MW Francis turbine under small opening condition

    NASA Astrophysics Data System (ADS)

    Gong, R. Z.; Wang, H. G.; Yao, Y.; Shu, L. F.; Huang, Y. J.

    2012-11-01

    In order to study the cause of abnormal vibration in large Francis turbine under small opening condition, CFD method was adopted to analyze the flow filed and pressure fluctuation. Numerical simulation was performed on the commercial CFD code Ansys FLUENT 12, using DES method. After an effective validation of the computation result, the flow behaviour of internal flow field under small opening condition is analyzed. Pressure fluctuation in different working mode is obtained by unsteady CFD simulation, and results is compared to study its change. Radial force fluctuation is also analyzed. The result shows that the unstable flow under small opening condition leads to an increase of turbine instability in reverse pump mode, and is one possible reason of the abnormal oscillation.

  20. SM1.3 Seismic Centers Data Acquisition: an introduction to Antelope, EarthWorm, SeisComP and their usage around the world

    NASA Astrophysics Data System (ADS)

    Pesaresi, Damiano; Sleeman, Reinoud

    2010-05-01

    Many medium to big size seismic data centers around the world are facing the same question: which software to use to acquire seismic data in real-time? A home-made or a commercial one? Both choices have pros and cons. The in-house development of software usually requires an increased investment in human resources rather than a financial investment. However, the advantage of fully accomplishing your own needs could be put in danger when the software engineer quits the job! Commercial software offers the advantage of being maintained, but it may require both a considerable financial investment and training. The main seismic software data acquisition suites available nowadays are the public domain SeisComP and EarthWorm packages and the commercial package Antelope. Nanometrics, Guralp and RefTek also provide seismic data acquisition software, but they are mainly intended for single station/network acquisition. Antelope is a software package for real-time acquisition and processing of seismic network data, with its roots in the academic seismological community. The software is developed by Boulder Real Time Technology (BRTT) and commercialized by Kinemetrics. It is used by IRIS affiliates for off-line data processing and it is the main acquisition tool for the USArray program and data centers in Europe like the ORFEUS Data Center, OGS (Italy), ZAMG (Austria), ARSO (Slovenia) and GFU (Czech Republic). SeisComP was originally developed for the GEOFON global network to provide a system for data acquisition, data exchange (SeedLink protocol) and automatic processing. It has evolved into to a widely distributed, networked seismographic system for data acquisition and real-time data exchange over Internet and is supported by ORFEUS as the standard seismic data acquisition tool in Europe. SeisComP3 is the next generation of the software and was developed for the German Indonesian Tsunami Early Warning System (GITEWS). SeisComP is licensed by GFZ (free of charge) and maintained by a private company (GEMPA). EarthWorm was originally developed by United States Geological Survey (USGS) to exchange data with the Canadian seismologists. Its is now used by several institution around the world. It is maintained and developed by a commercial software house, ISTI.

  1. Coverbal gestures in the recovery from severe fluent aphasia: a pilot study.

    PubMed

    Carlomagno, Sergio; Zulian, Nicola; Razzano, Carmelina; De Mercurio, Ilaria; Marini, Andrea

    2013-01-01

    This post hoc study investigated coverbal gesture patterns in two persons with chronic Wernicke's aphasia. They had both received therapy focusing on multimodal communication therapy, and their pre- and post-therapy verbal and gestural skills in face-to-face conversational interaction with their speech therapist were analysed by administering a partial barrier Referential Communication Task (RCT). The RCT sessions were reviewed in order to analyse: (a) participant coverbal gesture occurrence and types when in speaker role, (b) distribution of iconic gestures in the RCT communicative moves, (c) recognisable semantic content, and (d) the ways in which gestures were combined with empty or paraphasic speech. At post-therapy assessment only one participant showed improved communication skills in spite of his persistent language deficits. The improvement corresponded to changes on all gesturing measures, suggesting thereby that his communication relied more on gestural information. No measurable changes were observed for the non-responding participant-a finding indicating that the coverbal gesture measures used in this study might account for the different outcomes. These results point to the potential role of gestures in treatment aimed at fostering recovery from severe fluent aphasia. Moreover, this pattern of improvement runs contrary to a view of gestures used as a pure substitute for lexical items, in the communication of people with severe fluent aphasia. The readers will describe how to assess and interpret the patterns of coverbal gesturing in persons with fluent aphasia. They will also recognize the potential role of coverbal gestures in recovery from severe fluent aphasia. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Epidural cortical stimulation as adjunctive treatment for non-fluent aphasia: preliminary findings.

    PubMed

    Cherney, Leora R; Erickson, Robert K; Small, Steven L

    2010-09-01

    This study evaluated the safety and feasibility of targeted epidural cortical stimulation delivered concurrently with intensive speech-language therapy for treatment of chronic non-fluent aphasia. Eight stroke survivors with non-fluent aphasia received intensive behavioural therapy for 3 h daily for 6 weeks using a combination of articulation drills, oral reading and conversational practice. Four of these participants (investigational participants) also underwent functional MRI guided surgical implantation of an epidural stimulation device which was activated only during therapy sessions. Behavioural data were collected before treatment, immediately after treatment and at 6 and 12 weeks following termination of therapy. Imaging data were collected before and after treatment. Investigational participants showed a mean Aphasia Quotient change of 8.0 points immediately post-therapy and at the 6 week follow-up, and 12.3 points at 12 weeks. The control group had changes of 4.6, 5.5 and 3.6 points, respectively. Similar changes were noted on subjective caregiver ratings. Functional imaging suggested increased consolidation of activity in interventional participants. Behavioural speech-language therapy improves non-fluent aphasia, independent of cortical stimulation. However, epidural stimulation of the ipsilesional premotor cortex may augment this effect, with the largest effects after completion of therapy. The neural mechanisms underlying these effects are manifested in the brain by decreases in the volume of activity globally and in particular regions. Although the number of participants enrolled in this trial precludes definitive conclusions, targeted epidural cortical stimulation appears safe and may be a feasible adjunctive treatment for non-fluent aphasia, particularly when the aphasia is more severe.

  3. Separation of trait and state in stuttering.

    PubMed

    Connally, Emily L; Ward, David; Pliatsikas, Christos; Finnegan, Sarah; Jenkinson, Mark; Boyles, Rowan; Watkins, Kate E

    2018-04-06

    Stuttering is a disorder in which the smooth flow of speech is interrupted. People who stutter show structural and functional abnormalities in the speech and motor system. It is unclear whether functional differences reflect general traits of the disorder or are specifically related to the dysfluent speech state. We used a hierarchical approach to separate state and trait effects within stuttering. We collected sparse-sampled functional MRI during two overt speech tasks (sentence reading and picture description) in 17 people who stutter and 16 fluent controls. Separate analyses identified indicators of: (1) general traits of people who stutter; (2) frequency of dysfluent speech states in subgroups of people who stutter; and (3) the differences between fluent and dysfluent states in people who stutter. We found that reduced activation of left auditory cortex, inferior frontal cortex bilaterally, and medial cerebellum were general traits that distinguished fluent speech in people who stutter from that of controls. The stuttering subgroup with higher frequency of dysfluent states during scanning (n = 9) had reduced activation in the right subcortical grey matter, left temporo-occipital cortex, the cingulate cortex, and medial parieto-occipital cortex relative to the subgroup who were more fluent (n = 8). Finally, during dysfluent states relative to fluent ones, there was greater activation of inferior frontal and premotor cortex extending into the frontal operculum, bilaterally. The above differences were seen across both tasks. Subcortical state effects differed according to the task. Overall, our data emphasise the independence of trait and state effects in stuttering. © 2018 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.

  4. Energy consumption analysis and simulation of waste heat recovery technology of ceramic rotary kiln

    NASA Astrophysics Data System (ADS)

    Chen, Zhiguang; Zhou, Yu; Qin, Chaokui; Zhang, Xuemei

    2018-03-01

    Ceramsite is widely used in the construction industry, insulation works and oil industry in China, and the manufacture equipment is mainly industrial kiln. In this paper, energy consumption analysis had been carried out through experimental test of a Ceramsite kiln in Henan province. Results showed that the discharge temperature of Ceramsite was about 1393K, and the waste heat accounted for 22.1% of the total energy consumption. A structure of cyclone preheater which recovered waste heat of the high temperature Ceramsite by blast cooling was designed. Then, using Fluent software, performance of the unit was simulated. The minimum temperature that Ceramsite could reach, heat dissipating capacity of Ceramsite, temperature at air outlet, wall temperature of the unit and pressure loss were analyzed. Performance of the designed unit under different inlet velocity was analyzed as well.

  5. Numerical analysis of hydrodynamics in a rotor-stator reactor for biodiesel synthesis

    NASA Astrophysics Data System (ADS)

    Wen, Zhuqing; Petera, Jerzy

    2016-06-01

    A rotor-stator spinning disk reactor for intensified biodiesel synthesis is described and numerically simulated. The reactor consists of two flat disks, located coaxially and parallel to each other with a gap ranging from 0.1 mm to 0.2 mm between the disks. The upper disk is located on a rotating shaft while the lower disk is stationary. The feed liquids, triglycerides (TG) and methanol are introduced coaxially along the center line of rotating disk and stationary disk, respectively. Fluid hydrodynamics in the reactor for synthesis of biodiesel from TG and methanol in the presence of a sodium hydroxide catalyst are simulated, using convection-diffusion-reaction species transport model by the CFD software ANSYS©Fluent v. 13.0. The effects of upper disk's spinning speed, gap size and flow rates at inlets are evaluated.

  6. Study on steam pressure characteristics in various types of nozzles

    NASA Astrophysics Data System (ADS)

    Firman; Anshar, Muhammad

    2018-03-01

    Steam Jet Refrigeration (SJR) is one of the most widely applied technologies in the industry. The SJR system was utilizes residual steam from the steam generator and then flowed through the nozzle to a tank that was containing liquid. The nozzle converts the pressure energy into kinetic energy. Thus, it can evaporate the liquid briefly and release it to the condenser. The chilled water, was produced from the condenser, can be used to cool the product through a heat transfer process. This research aims to study the characteristics of vapor pressure in different types of nozzles using a simulation. The Simulation was performed using ANSYS FLUENT software for nozzle types such as convergent, convrgent-parallel, and convergent-divergent. The results of this study was presented the visualization of pressure in nozzles and was been validated with experiment data.

  7. Improved design of a cone-shaped rotating disk for shear force loading in a cell culture plate

    NASA Astrophysics Data System (ADS)

    Keawprachum, Boonrit; Limjeerajarus, Nuttapol; Nakalekha Limjeerajarus, Chalida; Srisungsitthisunti, Pornsak

    2018-01-01

    In our previous study, a cone-shaped rotating disk had been designed and proposed for generating shear force on the cell in a cell culture plate. This study aims to improve the design of the rotating disk that could provide a better uniformity of shear stress distribution. The top of the cone was designed to be trimmed off to obtain a flat head area. The effect of tilt angle (θ) was numerically studied using computational fluid dynamics (CFD) technique in ANSYS-Fluent software. The results revealed that for 500 rpm, the new designed rotating disk with a height of cone-shaped top to the plate bottom h = 1 mm and θ = 25° provided the best uniformity of 0.820 which was better than that of the previously designed.

  8. Supporting Students in Making Sense of Connections and in Becoming Perceptually Fluent in Making Connections among Multiple Graphical Representations

    ERIC Educational Resources Information Center

    Rau, Martina A.; Aleven, Vincent; Rummel, Nikol

    2017-01-01

    Prior research shows that multiple representations can enhance learning, provided that students make connections among them. We hypothesized that support for connection making is most effective in enhancing learning of domain knowledge if it helps students both in making sense of these connections and in becoming perceptually fluent in making…

  9. Reading Performance Profile of Children with Dyslexia in Primary and Secondary School Students

    ERIC Educational Resources Information Center

    Balci, Emine; Çayir, Aybala

    2018-01-01

    The purpose of the present research was to provide information to the community about the reading subskill profiles of children with dyslexia in primary and secondary school students. 175 children (aged 7-15 yrs) were examined on a varied set of phonological coding, spelling and fluent reading tasks. For this purpose, students' fluent reading were…

  10. Stimulating Conversation: Enhancement of Elicited Propositional Speech in a Patient with Chronic Non-Fluent Aphasia following Transcranial Magnetic Stimulation

    ERIC Educational Resources Information Center

    Hamilton, Roy H.; Sanders, Linda; Benson, Jennifer; Faseyitan, Olufunsho; Norise, Catherine; Naeser, Margaret; Martin, Paula; Coslett, H. Branch

    2010-01-01

    Although evidence suggests that patients with left hemisphere strokes and non-fluent aphasia who receive 1Hz repetitive transcranial magnetic stimulation (rTMS) over the intact right inferior frontal gyrus experience persistent benefits in naming, it remains unclear whether the effects of rTMS in these patients generalize to other language…

  11. Using Self- and Parent-Reports to Test the Association between Peer Victimization and Internalizing Symptoms in Verbally Fluent Adolescents with ASD

    ERIC Educational Resources Information Center

    Adams, Ryan E.; Fredstrom, Bridget K.; Duncan, Amie W.; Holleb, Lauren J.; Bishop, Somer L.

    2014-01-01

    The current study tested the associations between peer victimization and internalizing symptoms in 54 verbally fluent adolescent males with a diagnosis of autism spectrum disorder. Adolescent- and parent-reports of multiple types of peer victimization and internalizing symptoms were used. First, the validity and reliability of the…

  12. Using Words Instead of Jumbled Characters as Stimuli in Keyboard Training Facilitates Fluent Performance

    ERIC Educational Resources Information Center

    DeFulio, Anthony; Crone-Todd, Darlene E.; Long, Lauren V.; Nuzzo, Paul A.; Silverman, Kenneth

    2011-01-01

    Keyboarding skill is an important target for adult education programs due to the ubiquity of computers in modern work environments. A previous study showed that novice typists learned key locations quickly but that fluency took a relatively long time to develop. In the present study, novice typists achieved fluent performance in nearly half the…

  13. Video Self-Modeling Technique That Can Be Used in Improving the Abilities of Fluent Reading and Fluent Speaking

    ERIC Educational Resources Information Center

    Sen, Ülker

    2016-01-01

    The use of technology in the field of education makes the educational process more efficient and motivating. Technological tools are used for developing the communication skills of students and teachers in the learning process increasing the participation, supporting the peer, the realization of collaborative learning. The use of technology is…

  14. The Integrity of Anticipatory Coarticulation in Fluent and Non-Fluent Tokens of Adults Who Stutter

    ERIC Educational Resources Information Center

    Sussman, Harvey M.; Byrd, Courtney T.; Guitar, Barry

    2011-01-01

    This article analysed the acoustic structure of voiced stop ++ vowel sequences in a group of persons who stutter (PWS). This phonetic unit was chosen because successful production is highly dependent on the differential tweaking of right-to-left anticipatory coarticulation as a function of stop place. Thus, essential elements of both speech motor…

  15. The Role of Interest in Students' Writing Fluency and the Quality of the Product.

    ERIC Educational Resources Information Center

    Lewis, Dorothy P.

    A study was conducted to examine the effects of students' interests on their writing. A group of 571 high school seniors, fluent and nonfluent in writing, completed a questionnaire dealing with aspects of writing interest, such as subject, form, or voice. Tape recorded interviews addressing the same aspects were conducted with 11 fluent seniors…

  16. The 1989 Educational Software Preview Guide.

    ERIC Educational Resources Information Center

    Educational Software Evaluation Consortium, Menlo Park, CA.

    Developed to help educators locate microcomputer software programs they may want to preview for students in grades K-12, this guide lists commercially available instructional software programs that have been favorably reviewed by members of the Educational Software Evaluation Consortium. Programs are arranged alphabetically by title within…

  17. Masked Priming Effects in Aphasia: Evidence for Altered Automatic Spreading Activation

    PubMed Central

    Silkes, JoAnn P.; Rogers, Margaret A.

    2015-01-01

    Purpose Previous research has suggested that impairments of automatic spreading activation may underlie some aphasic language deficits. This study further investigated the status of automatic spreading activation in individuals with aphasia as compared with typical adults. Method Participants were 21 individuals with aphasia (12 fluent, 9 non-fluent) and 31 typical adults. Reaction time data were collected on a lexical decision task with masked repetition primes, assessed at 11 different interstimulus intervals (ISIs). Masked primes were used to assess automatic spreading activation without the confound of conscious processing. The various ISIs were used to assess the time to onset, and duration, of priming effects. Results The control group showed maximal priming in the 200 ms ISI condition, with significant priming at a range of ISIs surrounding that peak. Participants with both fluent and non-fluent aphasia showed maximal priming effects in the 250 ms ISI condition, and primed across a smaller range of ISIs than the control group. Conclusions Results suggest that individuals with aphasia have slowed automatic spreading activation, and impaired maintenance of activation over time, regardless of fluency classification. These findings have implications for understanding aphasic language impairment and for development of aphasia treatments designed directly address automatic language processes. PMID:22411281

  18. Numerical Investigation of the Effect of C/O Mole Ratio on the Performance of Rotary Hearth Furnace Using a Combined Model

    NASA Astrophysics Data System (ADS)

    Liu, Ying; Wen, Zhi; Lou, Guofeng; Li, Zhi; Yong, Haiquan; Feng, Xiaohong

    2014-12-01

    In a rotary hearth furnace (RHF) the direct reduction of composite pellets and processes of heat and mass transfer as well as combustion in the chamber of RHF influence each other. These mutual interactions should be considered when an accurate model of RHF is established. This paper provides a combined model that incorporates two sub-models to investigate the effects of C/O mole ratio in the feed pellets on the reduction kinetics and heat and mass transfer as well as combustion processes in the chamber of a pilot-scale RHF. One of the sub-models is established to describe the direct reduction process of composite pellets on the hearth of RHF. Heat and mass transfer within the pellet, chemical reactions, and radiative heat transfer from furnace walls and combustion gas to the surface of the pellet are considered in the model. The other sub-model is used to simulate gas flow and combustion process in the chamber of RHF by using commercial CFD software, FLUENT. The two sub-models were linked through boundary conditions and heat, mass sources. Cases for pellets with different C/O mole ratio were calculated by the combined model. The calculation results showed that the degree of metallization, the total amounts of carbon monoxide escaping from the pellet, and heat absorbed by chemical reactions within the pellet as well as CO and CO2 concentrations in the furnace increase with the increase of C/O mole ratio ranging from 0.6 to 1.0, when calculation conditions are the same except for C/O molar ratio. Carbon content in the pellet has little influence on temperature distribution in the furnace under the same calculation conditions except for C/O mole ratio in the feed pellets.

  19. Numerical investigation of forced convection of nano fluid flow in horizontal U-longitudinal finned tube heat exchanger

    NASA Astrophysics Data System (ADS)

    Qasim, S. M.; Sahar, A. F. A.; Firas, A. A.

    2015-11-01

    A numerical study has been carried out to investigate the heat transfer by laminar forced convection of nanofluid taking Titania (TiO2) and Alumina (Al2O3) as nanoparticles and the water as based fluid in a three dimensional plain and U-longitudinal finned tube heat exchanger. A Solid WORKS PREMIUM 2012 is used to draw the geometries of plain tube heat exchanger or U-longitudinal copper finned tube heat exchanger. Four U-longitudinal copper fins have 100 cm long, 3.8cm height and 1mm thickness are attached to a straight copper tube of 100 cm length, 2.2 cm inner diameter and 2.39 cm outer diameter. The governing equations which used as continuity, momentum and energy equations under assumptions are utilized to predict the flow field, temperature distribution, and heat transfer of the heat exchanger. The finite volume approach is used to obtain all the computational results using commercial ANSYS Fluent copy package 14.0 with assist of solid works and Gambit software program. The effect of various parameters on the performance of heat exchanger are investigated numerically such as Reynolds' number (ranging from 270 to 1900), volume consternation of nanoparticles (0.2%, 0.4%, 0.6%, 0.8%), type of nanoparticles, and mass flow rate of nanofluid in the hot region of heat exchanger. For 0.8% consternation of nanoparticles, heat transfer has significant enhancement in both nanofluids. It can be found about 7.3% for TiO2 and about 7.5% for Al2O3 compared with the water only as a working fluid.

  20. Turbulent heat transfer and nanofluid flow in a protruded ribbed square passage

    NASA Astrophysics Data System (ADS)

    Kumar, Sunil; Kothiyal, Alok Darshan; Bisht, Mangal Singh; Kumar, Anil

    In this article, turbulent heat transfer of nanofluid flow in square passage with protruded rib shape is numerically and experimentally studied over Reynolds number ranges of 4000-18000. Different nanoparticles (Al2O3, CuO, and ZnO), with different concentration (φ) range of 1-4% and different nanoparticle diameter (dnp) range of 30-45 nm are disperse in water (base fluid). Several parameters such as stream wise distance (Xs /dp) range of 1.4-2.6, span wise distance (Ys /dp) range of 1.4-2.6, ratio of protruded height to print diameter (ep /dp) range of 0.83-1.67 also studied to find the consequence on thermal and hydrodynamic characteristics. Simulations were carried out to obtain heat and fluid flow behaviour of smooth and ribbed square channel using commercial CFD software, ANSYS 15.0 (Fluent). Renormalization k - ε model was employed to assess the influence of protruded ribs on turbulent flow and velocity field. The outcome indicates that Al2O3 nanofluid has the highest value of average Nusselt number as compare to other nanofluids. The average Nusselt number increases as the concentration increases and it decreases as nanoparticle diameter increases. The thermal hydrodynamic performance parameter based on equal pumping power, average Nusselt number and average friction factor were found to be highest for Al2O3, φ = 0.04, dnp = 30 nm, Xs /dp = 1.8, Ys /dp = 1.8 and ep /dp = 1.0 . The numerical data are compared with the corresponding experimental data. Comparison between CFD and experimental analysis results showed that good agreement as the data fell within ±7.0% error band.

  1. Numerical calculation on infrared characteristics of the special vehicle exhaust system

    NASA Astrophysics Data System (ADS)

    Feng, Yun-song; Li, Xiao-xia; Jin, Wei

    2017-10-01

    For mastery of infrared radiation characteristics and flow field of the special vehicle exhaust system, first, a physical model of the special vehicle exhaust system is established with the Gambit, and the mathematical model of flow field is determined. Secondly, software Fluent6.3 is used to simulated the 3-D exterior flow field of the special vehicle exhaust system, and the datum of flow field, such as temperature, pressure and density, are obtained. Thirdly, based on the plume temperature, the special vehicle exhaust space is divided. The exhaust is equivalent to a gray-body. A calculating model of the vehicle exhaust infrared radiation is established, and the exhaust infrared radiation characteristics are calculated by the software MATLAB, then the spatial distribution curves are drawn. Finally, the numerical results are analyzing, and the basic laws of the special vehicle exhaust infrared radiation are explored. The results show that with the increase of the engine speed, the temperature of the exhaust pipe wall of the special vehicle increases, and the temperature and pressure of the exhaust gas flow field increase, which leads to the enhancement of the infrared radiation intensity

  2. Numerical Simulation of Liquid Metal RF MEMS Switch Based on EWOD

    NASA Astrophysics Data System (ADS)

    Liu, Tingting; Gao, Yang; Yang, Tao; Guo, Huihui

    2018-03-01

    Conventional RF MEMS switches rely on metal-to-dielectric or metal-to-metal contacts. Some problems in the “solid-solid” contact, such as contact degradation, signal bounce and poor reliability, can be solved by using “liquid-solid” contact. The RF MEMS switch based on liquid metal is characterized by small contact resistance, no moving parts, high reliability and long life. Using electrowetting-on-dielectric (EWOD) way to control the movement of liquid metal in the RF MEMS switch, to achieve the “on” and “off” of the switch. In this paper, the electrical characteristics and RF characteristics of RF MEMS switches are simulated by fluid mechanics software FLUENT and electromagnetic simulation software HFSS. The effects of driving voltage, switching time, dielectric layer, hydrophobic layer material and thickness, switching channel height on the RF characteristics are studied. The results show that to increase the external voltage to the threshold voltage of 58V, the liquid metal began to move, and the switching time from “off” state to “on” state is 16ms. In the 0~20GHz frequency range, the switch insertion loss is less than 0.28dB, isolation is better than 23.32dB.

  3. The 1990-91 Educational Software Preview Guide.

    ERIC Educational Resources Information Center

    Best, Anita, Ed.; And Others

    Developed to help educators locate microcomputer software programs they may want to preview for students in grades K-12, this guide lists commercially available microcomputer software programs that have been favorably reviewed by members of the Educational Software Evaluation Consortium. Programs are arranged alphabetically by title within…

  4. Neural network model for growth of Salmonella serotypes in ground chicken subjected to temperature abuse during cold storage for application in HACCP and risk assessment

    USDA-ARS?s Scientific Manuscript database

    With the advent of commercial software applications, it is now easy to develop neural network models for predictive microbiology applications. However, different versions of the model may be required to meet the divergent needs of model users. In the current study, the commercial software applicat...

  5. Feature Selection for Evolutionary Commercial-off-the-Shelf Software: Studies Focusing on Time-to-Market, Innovation and Hedonic-Utilitarian Trade-Offs

    ERIC Educational Resources Information Center

    Kakar, Adarsh Kumar

    2013-01-01

    Feature selection is one of the most important decisions made by product managers. This three article study investigates the concepts, tools and techniques for making trade-off decisions of introducing new features in evolving Commercial-Off-The-Shelf (COTS) software products. The first article investigates the efficacy of various feature…

  6. Slowed articulation rate is a sensitive diagnostic marker for identifying non-fluent primary progressive aphasia

    PubMed Central

    Cordella, Claire; Dickerson, Bradford C.; Quimby, Megan; Yunusova, Yana; Green, Jordan R.

    2016-01-01

    Background Primary progressive aphasia (PPA) is a neurodegenerative aphasic syndrome with three distinct clinical variants: non-fluent (nfvPPA), logopenic (lvPPA), and semantic (svPPA). Speech (non-) fluency is a key diagnostic marker used to aid identification of the clinical variants, and researchers have been actively developing diagnostic tools to assess speech fluency. Current approaches reveal coarse differences in fluency between subgroups, but often fail to clearly differentiate nfvPPA from the variably fluent lvPPA. More robust subtype differentiation may be possible with finer-grained measures of fluency. Aims We sought to identify the quantitative measures of speech rate—including articulation rate and pausing measures—that best differentiated PPA subtypes, specifically the non-fluent group (nfvPPA) from the more fluent groups (lvPPA, svPPA). The diagnostic accuracy of the quantitative speech rate variables was compared to that of a speech fluency impairment rating made by clinicians. Methods and Procedures Automatic estimates of pause and speech segment durations and rate measures were derived from connected speech samples of participants with PPA (N=38; 11 nfvPPA, 14 lvPPA, 13 svPPA) and healthy age-matched controls (N=8). Clinician ratings of fluency impairment were made using a previously validated clinician rating scale developed specifically for use in PPA. Receiver operating characteristic (ROC) analyses enabled a quantification of diagnostic accuracy. Outcomes and Results Among the quantitative measures, articulation rate was the most effective for differentiating between nfvPPA and the more fluent lvPPA and svPPA groups. The diagnostic accuracy of both speech and articulation rate measures was markedly better than that of the clinician rating scale, and articulation rate was the best classifier overall. Area under the curve (AUC) values for articulation rate were good to excellent for identifying nfvPPA from both svPPA (AUC=.96) and lvPPA (AUC=.86). Cross-validation of accuracy results for articulation rate showed good generalizability outside the training dataset. Conclusions Results provide empirical support for (1) the efficacy of quantitative assessments of speech fluency and (2) a distinct non-fluent PPA subtype characterized, at least in part, by an underlying disturbance in speech motor control. The trend toward improved classifier performance for quantitative rate measures demonstrates the potential for a more accurate and reliable approach to subtyping in the fluency domain, and suggests that articulation rate may be a useful input variable as part of a multi-dimensional clinical subtyping approach. PMID:28757671

  7. Software To Go: A Catalog of Software Available for Loan.

    ERIC Educational Resources Information Center

    Kurlychek, Ken, Comp.

    This catalog lists the holdings of the Software To Go software lending library and clearinghouse for programs and agencies serving students or clients who are deaf or hard of hearing. An introduction describes the clearinghouse and its collection of software, much of it commercial and copyrighted material, for Apple, Macintosh, and IBM (MS-DOS)…

  8. Software Epistemology

    DTIC Science & Technology

    2016-03-01

    in-vitro decision to incubate a startup, Lexumo [7], which is developing a commercial Software as a Service ( SaaS ) vulnerability assessment...LTS Label Transition System MUSE Mining and Understanding Software Enclaves RTEMS Real-Time Executive for Multi-processor Systems SaaS Software ...as a Service SSA Static Single Assignment SWE Software Epistemology UD/DU Def-Use/Use-Def Chains (Dataflow Graph)

  9. Speech Skill Learning of Persons Who Stutter and Fluent Speakers under Single and Dual Task Conditions

    ERIC Educational Resources Information Center

    Smits-Bandstra, Sarah; De Nil, Luc

    2009-01-01

    Two studies compared the accuracy and efficiency of initiating oral reading of nonsense syllables by persons who stutter (PWS) and fluent speakers (PNS) over practise. Findings of Study One, comparing 12 PWS and 12 PNS, replicated previous findings of slow speech sequence initiation over practise by PWS relative to PNS. In Study Two, nine PWS and…

  10. The Impact of Input Quality on Early Sign Development in Native and Non-Native Language Learners

    ERIC Educational Resources Information Center

    Lu, Jenny; Jones, Anna; Morgan, Gary

    2016-01-01

    There is debate about how input variation influences child language. Most deaf children are exposed to a sign language from their non-fluent hearing parents and experience a delay in exposure to accessible language. A small number of children receive language input from their deaf parents who are fluent signers. Thus it is possible to document the…

  11. Cultivating Culturally Fluent Leaders for the Future of Kinesiology. 2016 NAKHE Hally Beth Poindexter Young Scholar Award

    ERIC Educational Resources Information Center

    James-Hassan, Martha J.

    2016-01-01

    This article posits that each content area that falls under the umbrella of kinesiology must develop a future cadre of professionals who are competent in their content knowledge and are trained as leaders who are able to understand the essential impacts of culture on their work. The intentional development of culturally fluent leaders should be a…

  12. Case Study on the Effect of Word Repetition Method Supported by Neurological Affecting Model on Fluent Reading

    ERIC Educational Resources Information Center

    Duran, Erol

    2013-01-01

    This research is a case study which is a qualitative study model and named as example event as well. The purpose of this research is determining the effect of word repetitive reading method supported with neurological affecting model on fluent reading. In this study, False Analysis Inventory was used in order to determine the student's oral…

  13. Software Acquisition Improvement in the Aeronautical Systems Center

    DTIC Science & Technology

    2008-09-01

    software fielded, a variety of different methods were suggested by the interviewees. These included blocks, suites and other tailored processes developed...12 Selection of Research Method ...DoD look to the commercial market to buy tools, methods , environments, and application software, instead of custom-built software (DSB: 1987). These

  14. Features of free software packages in flow cytometry: a comparison between four non-commercial software sources.

    PubMed

    Sahraneshin Samani, Fazel; Moore, Jodene K; Khosravani, Pardis; Ebrahimi, Marzieh

    2014-08-01

    Flow cytometers designed to analyze large particles are enabling new applications in biology. Data analysis is a critical component of the process FCM. In this article we compare features of four free software packages including WinMDI, Cyflogic, Flowing software, and Cytobank.

  15. Models for Deploying Open Source and Commercial Software to Support Earth Science Data Processing and Distribution

    NASA Astrophysics Data System (ADS)

    Yetman, G.; Downs, R. R.

    2011-12-01

    Software deployment is needed to process and distribute scientific data throughout the data lifecycle. Developing software in-house can take software development teams away from other software development projects and can require efforts to maintain the software over time. Adopting and reusing software and system modules that have been previously developed by others can reduce in-house software development and maintenance costs and can contribute to the quality of the system being developed. A variety of models are available for reusing and deploying software and systems that have been developed by others. These deployment models include open source software, vendor-supported open source software, commercial software, and combinations of these approaches. Deployment in Earth science data processing and distribution has demonstrated the advantages and drawbacks of each model. Deploying open source software offers advantages for developing and maintaining scientific data processing systems and applications. By joining an open source community that is developing a particular system module or application, a scientific data processing team can contribute to aspects of the software development without having to commit to developing the software alone. Communities of interested developers can share the work while focusing on activities that utilize in-house expertise and addresses internal requirements. Maintenance is also shared by members of the community. Deploying vendor-supported open source software offers similar advantages to open source software. However, by procuring the services of a vendor, the in-house team can rely on the vendor to provide, install, and maintain the software over time. Vendor-supported open source software may be ideal for teams that recognize the value of an open source software component or application and would like to contribute to the effort, but do not have the time or expertise to contribute extensively. Vendor-supported software may also have the additional benefits of guaranteed up-time, bug fixes, and vendor-added enhancements. Deploying commercial software can be advantageous for obtaining system or software components offered by a vendor that meet in-house requirements. The vendor can be contracted to provide installation, support and maintenance services as needed. Combining these options offers a menu of choices, enabling selection of system components or software modules that meet the evolving requirements encountered throughout the scientific data lifecycle.

  16. University Software Ownership and Litigation: A First Examination*

    PubMed Central

    Rai, Arti K.; Allison, John R.; Sampat, Bhaven N.

    2013-01-01

    Software patents and university-owned patents represent two of the most controversial intellectual property developments of the last twenty-five years. Despite this reality, and concerns that universities act as “patent trolls” when they assert software patents in litigation against successful commercializers, no scholar has systematically examined the ownership and litigation of university software patents. In this Article, we present the first such examination. Our empirical research reveals that software patents represent a significant and growing proportion of university patent holdings. Additionally, the most important determinant of the number of software patents a university owns is not its research and development (“R&D”) expenditures (whether computer science-related or otherwise) but, rather, its tendency to seek patents in other areas. In other words, universities appear to take a “one size fits all” approach to patenting their inventions. This one size fits all approach is problematic given the empirical evidence that software is likely to follow a different commercialization path than other types of invention. Thus, it is perhaps not surprising that we see a number of lawsuits in which university software patents have been used not for purposes of fostering commercialization, but instead, to extract rents in apparent holdup litigation. The Article concludes by examining whether this trend is likely to continue in the future, particularly given a 2006 Supreme Court decision that appears to diminish the holdup threat by recognizing the possibility of liability rules in patent suits, as well as recent case law that may call into question certain types of software patents. PMID:23750052

  17. Gestural recovery and the role of forward and reversed syllabic repetitions as stuttering inhibitors in adults.

    PubMed

    Kalinowski, Joseph; Saltuklaroglu, Tim; Guntupalli, Vijaya; Stuart, Andrew

    2004-06-10

    Instead of being the core stuttering 'problem', syllabic repetitions may be a biological mechanism, or 'solution', to the central involuntary stuttering block. Simply put, stuttering is an endogenous transitory state of 'shadowed speech', a choral speech derivative that allows for a neural release of the central block. To investigate this possibility, 14 adults who stutter read while listening to forward fluent speech, reversed fluent speech, forward stuttered speech, and reversed stuttered speech. All conditions induced significant degrees of stuttering inhibition when compared to a control condition. However, the reversed fluent condition was less powerful than the other three conditions ( approximately 42% vs. approximately 65%) for inhibiting stuttering. Stuttering inhibition appears to proceed by 'gestural recovery', made possible by the presence of an exogenous or 'second' set of speech gestures and engagement of mirror neurons. When reversed fluent speech was used, violations in normal gesture-time relationships (i.e., normal speech entropy) resulted in gestural configurations that apparently were inadequately recovered, and therefore, were not as conducive to high levels of stuttering inhibition. In contrast, high levels of encoding found in the simple syllabic structures of stuttered speech allowed its forward and reversed forms to be equally effective for gestural recovery and stuttering inhibition. The reversal of repeated syllables did not appear to significantly degrade the natural gesture-time relationships (i.e., they were perceptually recognizable). Thus, exogenous speech gestures that displayed near normal gestural relationships allowed for easy recovery and fluent productions via mirror systems, suggesting a more choral-like nature. The importance of syllabic repetitions is highlighted: both their perceived (exogenous) and produced (endogenous) forms appear to be fundamental, surface acoustic manifestations for central stuttering inhibition via the engagement of mirror neurons.

  18. Treatment of word-finding deficits in fluent aphasia through the manipulation of spatial attention: Preliminary findings

    PubMed Central

    Dotson, Vonetta M.; Singletary, Floris; Fuller, Renee; Koehler, Shirley; Moore, Anna Bacon; Gonzalez Rothi, Leslie J.; Crosson, Bruce

    2010-01-01

    Background Attention, the processing of one source of information to the exclusion of others, is important for most cognitive processes, including language. Evidence suggests not only that dysfunctional attention mechanisms contribute to language deficits after stroke, but also that orienting attention to a patient's ipsilesional hemispace recruits attention mechanisms in the intact hemisphere and improves language functions in some persons with aphasia. Aims The aim of the current research was to offer proof of concept for the strategy of improving picture-naming performance in fluent aphasia by moving stimuli into the left hemispace. It was hypothesised that repeated orientation of attention to the ipsilesional hemispace during picture naming would lead to improved naming accuracy for participants with fluent aphasia. Methods & Procedures Three participants with stable fluent aphasia received daily treatment sessions that consisted of naming simple line drawings presented 45 degrees to the left of body midline on a computer monitor. Naming probes were administered before initiation of the treatment protocol to establish a baseline, and before each treatment session to measure change during treatment. The C statistic was used to establish the stability of baseline performance and to determine whether the slope of the treatment phases differed significantly from the slope of the baseline. Outcomes & Results Two of the three participants showed significant improvement over baseline performance in the percent correct of naming probes. One participant showed no improvement over baseline accuracy. Conclusions Results suggest that engaging right-hemisphere attention mechanisms may improve naming accuracy in some people with fluent aphasia. Findings justify further investigation of this treatment in a larger controlled study. PMID:22131638

  19. Small Business Innovations (Integrated Database)

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Because of the diversity of NASA's information systems, it was necessary to develop DAVID as a central database management system. Under a Small Business Innovation Research (SBIR) grant, Ken Wanderman and Associates, Inc. designed software tools enabling scientists to interface with DAVID and commercial database management systems, as well as artificial intelligence programs. The software has been installed at a number of data centers and is commercially available.

  20. R&D to Market Success: BTO-Supported Technologies Commercialized from 2010-2015

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None, None

    2017-04-01

    Technology commercialization plays an essential role in almost every facet of the U.S. economy. It spurs private sector funding that supports innovative breakthroughs, drives growth through increased productivity and product development, increases American competitiveness, and creates domestic jobs. The BTO Technology Commercialization report is an annual publication offering the latest information on successfully commercialized technologies resulting in part from BTO’s research partnerships. This report defines a “commercialized technology” as a process, technique, design, machine, tool, material, or software that was developed with funds provided at least in part by BTO, and that has resulted in domestic sales or is inmore » use in the U.S. This definition also applies to open-source software products developed with support from BTO, all of which are currently distributed freely but are actively used for commercial purposes.« less

  1. Building Energy Management Open Source Software

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rahman, Saifur

    Funded by the U.S. Department of Energy in November 2013, a Building Energy Management Open Source Software (BEMOSS) platform was engineered to improve sensing and control of equipment in small- and medium-sized commercial buildings. According to the Energy Information Administration (EIA), small- (5,000 square feet or smaller) and medium-sized (between 5,001 to 50,000 square feet) commercial buildings constitute about 95% of all commercial buildings in the U.S. These buildings typically do not have Building Automation Systems (BAS) to monitor and control building operation. While commercial BAS solutions exist, including those from Siemens, Honeywell, Johnsons Controls and many more, they aremore » not cost effective in the context of small- and medium-sized commercial buildings, and typically work with specific controller products from the same company. BEMOSS targets small and medium-sized commercial buildings to address this gap.« less

  2. A tool to include gamma analysis software into a quality assurance program.

    PubMed

    Agnew, Christina E; McGarry, Conor K

    2016-03-01

    To provide a tool to enable gamma analysis software algorithms to be included in a quality assurance (QA) program. Four image sets were created comprising two geometric images to independently test the distance to agreement (DTA) and dose difference (DD) elements of the gamma algorithm, a clinical step and shoot IMRT field and a clinical VMAT arc. The images were analysed using global and local gamma analysis with 2 in-house and 8 commercially available software encompassing 15 software versions. The effect of image resolution on gamma pass rates was also investigated. All but one software accurately calculated the gamma passing rate for the geometric images. Variation in global gamma passing rates of 1% at 3%/3mm and over 2% at 1%/1mm was measured between software and software versions with analysis of appropriately sampled images. This study provides a suite of test images and the gamma pass rates achieved for a selection of commercially available software. This image suite will enable validation of gamma analysis software within a QA program and provide a frame of reference by which to compare results reported in the literature from various manufacturers and software versions. Copyright © 2015. Published by Elsevier Ireland Ltd.

  3. Speech Motor Control in Fluent and Dysfluent Speech Production of an Individual with Apraxia of Speech and Broca's Aphasia

    ERIC Educational Resources Information Center

    van Lieshout, Pascal H. H. M.; Bose, Arpita; Square, Paula A.; Steele, Catriona M.

    2007-01-01

    Apraxia of speech (AOS) is typically described as a motor-speech disorder with clinically well-defined symptoms, but without a clear understanding of the underlying problems in motor control. A number of studies have compared the speech of subjects with AOS to the fluent speech of controls, but only a few have included speech movement data and if…

  4. School Competence and Fluent Academic Performance: Informing Assessment of Educational Outcomes in Survivors of Pediatric Medulloblastoma.

    PubMed

    Holland, Alice Ann; Hughes, Carroll W; Stavinoha, Peter L

    2015-01-01

    Academic difficulties are widely acknowledged but not adequately studied in survivors of pediatric medulloblastoma. Although most survivors require special education services and are significantly less likely than healthy peers to finish high school, measured academic skills are typically average. This study sought to identify potential factors associated with academic difficulties in this population and focused on school competence and fluent academic performance. Thirty-six patients (ages 7-18 years old) were recruited through the Departments of Neurosurgery and Neuro-Oncology at Children's Medical Center Dallas and Cook Children's Medical Center in Fort Worth, TX. Participants completed a neuropsychological screening battery including selected Woodcock-Johnson III Tests of Achievement subtests. Parents completed the Child Behavior Checklist. School competence was significantly correlated with measured academic skills and fluency. Basic academic skill development was broadly average, in contrast to significantly worse fluent academic performance. School competence may have utility as a measure estimating levels of educational success in this population. Additionally, academic difficulties experienced by childhood medulloblastoma survivors may be better captured by measuring deficits in fluent academic performance rather than skills. Identification of these potential factors associated with educational outcomes of pediatric medulloblastoma survivors has significant implications for research, clinical assessment, and academic services/interventions.

  5. Rhythm in disguise: why singing may not hold the key to recovery from aphasia

    PubMed Central

    Kotz, Sonja A.; Henseler, Ilona; Turner, Robert; Geyer, Stefan

    2011-01-01

    The question of whether singing may be helpful for stroke patients with non-fluent aphasia has been debated for many years. However, the role of rhythm in speech recovery appears to have been neglected. In the current lesion study, we aimed to assess the relative importance of melody and rhythm for speech production in 17 non-fluent aphasics. Furthermore, we systematically alternated the lyrics to test for the influence of long-term memory and preserved motor automaticity in formulaic expressions. We controlled for vocal frequency variability, pitch accuracy, rhythmicity, syllable duration, phonetic complexity and other relevant factors, such as learning effects or the acoustic setting. Contrary to some opinion, our data suggest that singing may not be decisive for speech production in non-fluent aphasics. Instead, our results indicate that rhythm may be crucial, particularly for patients with lesions including the basal ganglia. Among the patients we studied, basal ganglia lesions accounted for more than 50% of the variance related to rhythmicity. Our findings therefore suggest that benefits typically attributed to melodic intoning in the past could actually have their roots in rhythm. Moreover, our data indicate that lyric production in non-fluent aphasics may be strongly mediated by long-term memory and motor automaticity, irrespective of whether lyrics are sung or spoken. PMID:21948939

  6. 48 CFR 208.7401 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... OF DEFENSE ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Enterprise Software Agreements 208.7401 Definitions. As used in this subpart— Enterprise software agreement means an agreement or a contract that is used to acquire designated commercial software or related services such as...

  7. 48 CFR 208.7401 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... OF DEFENSE ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Enterprise Software Agreements 208.7401 Definitions. As used in this subpart— Enterprise software agreement means an agreement or a contract that is used to acquire designated commercial software or related services such as...

  8. 48 CFR 208.7401 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... OF DEFENSE ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Enterprise Software Agreements 208.7401 Definitions. As used in this subpart— Enterprise software agreement means an agreement or a contract that is used to acquire designated commercial software or related services such as...

  9. 48 CFR 208.7401 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... OF DEFENSE ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Enterprise Software Agreements 208.7401 Definitions. As used in this subpart— Enterprise software agreement means an agreement or a contract that is used to acquire designated commercial software or related services such as...

  10. Open Source Software in Medium Size Organizations: Key Factors for Adoption

    ERIC Educational Resources Information Center

    Solomon, Jerry T.

    2010-01-01

    For-profit organizations are constantly evaluating new technologies to gain competitive advantage. One such technology, application software, has changed significantly over the past 25 years with the introduction of Open Source Software (OSS). In contrast to commercial software that is developed by private companies and sold to organizations, OSS…

  11. Turnitoff: Identifying and Fixing a Hole in Current Plagiarism Detection Software

    ERIC Educational Resources Information Center

    Heather, James

    2010-01-01

    In recent times, "plagiarism detection software" has become popular in universities and colleges, in an attempt to stem the tide of plagiarised student coursework. Such software attempts to detect any copied material and identify its source. The most popular such software is Turnitin, a commercial system used by thousands of institutions…

  12. A CFD Study on the Prediction of Cyclone Collection Efficiency

    NASA Astrophysics Data System (ADS)

    Gimbun, Jolius; Chuah, T. G.; Choong, Thomas S. Y.; Fakhru'L-Razi, A.

    2005-09-01

    This work presents a Computational Fluid Dynamics calculation to predict and to evaluate the effects of temperature, operating pressure and inlet velocity on the collection efficiency of gas cyclones. The numerical solutions were carried out using spreadsheet and commercial CFD code FLUENT 6.0. This paper also reviews four empirical models for the prediction of cyclone collection efficiency, namely Lapple [1], Koch and Licht [2], Li and Wang [3], and Iozia and Leith [4]. All the predictions proved to be satisfactory when compared with the presented experimental data. The CFD simulations predict the cyclone cut-off size for all operating conditions with a deviation of 3.7% from the experimental data. Specifically, results obtained from the computer modelling exercise have demonstrated that CFD model is the best method of modelling the cyclones collection efficiency.

  13. Numerical analysis of single and multiple jets

    NASA Astrophysics Data System (ADS)

    Boussoufi, Mustapha; Sabeur-Bendehina, Amina; Ouadha, Ahmed; Morsli, Souad; El Ganaoui, Mohammed

    2017-05-01

    The present study aims to use the concept of entropy generation in order to study numerically the flow and the interaction of multiple jets. Several configurations of a single jet surrounded by equidistant 3, 5, 7 and 9 circumferential jets have been studied. The turbulent incompressible Navier-Stokes equations have been solved numerically using the commercial computational fluid dynamics code Fluent. The standard k-ɛ model has been selected to assess the eddy viscosity. The domain has been reduced to a quarter of the geometry due to symmetry. Results for axial and radial velocities have been compared with experimental measurements from the literature. Furthermore, additional results involving entropy generation rate have been presented and discussed. Contribution to the topical issue "Materials for Energy harvesting, conversion and storage II (ICOME 2016)", edited by Jean-Michel Nunzi, Rachid Bennacer and Mohammed El Ganaoui

  14. Numerical and experimental investigation of turbine blade film cooling

    NASA Astrophysics Data System (ADS)

    Berkache, Amar; Dizene, Rabah

    2017-12-01

    The blades in a gas turbine engine are exposed to extreme temperature levels that exceed the melting temperature of the material. Therefore, efficient cooling is a requirement for high performance of the gas turbine engine. The present study investigates film cooling by means of 3D numerical simulations using a commercial code: Fluent. Three numerical models, namely k-ɛ, RSM and SST turbulence models; are applied and then prediction results are compared to experimental measurements conducted by PIV technique. The experimental model realized in the ENSEMA laboratory uses a flat plate with several rows of staggered holes. The performance of the injected flow into the mainstream is analyzed. The comparison shows that the RANS closure models improve the over-predictions of center-line film cooling velocities that is caused by the limitations of the RANS method due to its isotropy eddy diffusivity.

  15. Computational analysis of water entry of a circular section at constant velocity based on Reynold's averaged Navier-Stokes method

    NASA Astrophysics Data System (ADS)

    Uddin, M. Maruf; Fuad, Muzaddid-E.-Zaman; Rahaman, Md. Mashiur; Islam, M. Rabiul

    2017-12-01

    With the rapid decrease in the cost of computational infrastructure with more efficient algorithm for solving non-linear problems, Reynold's averaged Navier-Stokes (RaNS) based Computational Fluid Dynamics (CFD) has been used widely now-a-days. As a preliminary evaluation tool, CFD is used to calculate the hydrodynamic loads on offshore installations, ships, and other structures in the ocean at initial design stages. Traditionally, wedges have been studied more than circular cylinders because cylinder section has zero deadrise angle at the instant of water impact, which increases with increase of submergence. In Present study, RaNS based commercial code ANSYS Fluent is used to simulate the water entry of a circular section at constant velocity. It is seen that present computational results were compared with experiment and other numerical method.

  16. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Busbey, A.B.

    The Apple Macintosh has been available since 1984, but there has been little development of commercial geological software for it. The author briefly reviews what geological software is available for the Macintosh

  17. An off-the-shelf guider for the Palomar 200-inch telescope: interfacing amateur astronomy software with professional telescopes for an easy life

    NASA Astrophysics Data System (ADS)

    Clarke, Fraser; Lynn, James; Thatte, Niranjan; Tecza, Matthias

    2014-08-01

    We have developed a simple but effective guider for use with the Oxford-SWIFT integral field spectrograph on the Palomar 200-inch telescope. The guider uses mainly off-the-shelf components, including commercial amateur astronomy software to interface with the CCD camera, calculating guiding corrections, and send guide commands to the telescope. The only custom piece of software is an driver to provide an interface between the Palomar telescope control system and the industry standard 'ASCOM' system. Using existing commercial software provided a very cheap guider (<$5000) with minimal (<15 minutes) commissioning time. The final system provides sub-arcsecond guiding, and could easily be adapted to any other professional telescope

  18. Achieving Better Buying Power through Acquisition of Open Architecture Software Systems. Volume 2 Understanding Open Architecture Software Systems: Licensing and Security Research and Recommendations

    DTIC Science & Technology

    2016-01-06

    of- breed software components and software products lines (SPLs) that are subject to different IP license and cybersecurity requirements. The... commercially priced closed source software components, to be used in the design, implementation, deployment, and evolution of open architecture (OA... breed software components and software products lines (SPLs) that are subject to different IP license and cybersecurity requirements. The Department

  19. Research of working pulsation in closed angle based on rotating-sleeve distributing-flow system

    NASA Astrophysics Data System (ADS)

    Zhang, Yanjun; Zhang, Hongxin; Zhao, Qinghai; Jiang, Xiaotian; Cheng, Qianchang

    2017-08-01

    In order to reduce negative effects including hydraulic impact, noise and mechanical vibration, compression and expansion of piston pump in closed volume are used to optimize the angle between valve port and chamber. In addition, the mathematical model about pressurization and depressurization in pump chamber are analyzed based on distributing-flow characteristic, and it is necessary to use simulation software Fluent to simulate the distributing-flow fluid model so as to select the most suitable closed angle. As a result, when compression angle is 3°, the angle is closest to theoretical analysis and has the minimum influence on flow and pump pressure characteristic. Meanwhile, cavitation phenomenon appears in pump chamber in different closed angle on different degrees. Besides the flow pulsation is increasingly smaller with increasing expansion angle. Thus when expansion angle is 2°, the angle is more suitable for distributing-flow system.

  20. A numerical study of latent thermal energy storage in a phase change material/carbon panel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mekaddem, Najoua, E-mail: mekaddem.najoua@gmail.com; Ali, Samia Ben, E-mail: samia.benali@enig.rnu.tn; Hannachi, Ahmed, E-mail: ahmed.hannachi@enig.rnu.tn

    2016-07-25

    To reduce the energetic dependence of building, it has become necessary to explore and develop new materials promoting energy conservation. Because of their high storage capacity, phase change materials (PCMs) are efficient to store thermal energy. In this paper, a 3D model was studied for simulation of energy storing cycles to predict the performances of PCM loaded panels. Carbon was used as supporting material for the PCM. The simulation was based on the enthalpy method using Ansys Fluent software. The panel was exposed to a daily heat flow including the effects of convection and radiation. The results show that themore » temperature decreased of approximately 2.5°C with a time shift about 2 hours. The steady state was reached after four cycles. Thus, after four cycles the PCM showed its effects on the temperature conditioning.« less

  1. The influence of liquid-gas velocity ratio on the noise of the cooling tower

    NASA Astrophysics Data System (ADS)

    Yang, Bin; Liu, Xuanzuo; Chen, Chi; Zhao, Zhouli; Song, Jinchun

    2018-05-01

    The noise from the cooling tower has a great influence on psychological performance of human beings. The cooling tower noise mainly consists of fan noise, falling water noise and mechanical noise. This thesis used DES turbulence model with FH-W model to simulate the flow and sound pressure field in cooling tower based on CFD software FLUENT and analyzed the influence of different kinds noise, which affected by diverse factors, on the cooling tower noise. It can be concluded that the addition of cooling water can reduce the turbulence and vortex noise of the rotor fluid field in the cooling tower at some extent, but increase the impact noise of the liquid-gas two phase. In general, the cooling tower noise decreases with the velocity ratio of liquid to gas increasing, and reaches the lowest when the velocity ratio of liquid to gas is close to l.

  2. Computational Investigations in Rectangular Convergent and Divergent Ribbed Channels

    NASA Astrophysics Data System (ADS)

    Sivakumar, Karthikeyan; Kulasekharan, N.; Natarajan, E.

    2018-05-01

    Computational investigations on the rib turbulated flow inside a convergent and divergent rectangular channel with square ribs of different rib heights and different Reynolds numbers (Re=20,000, 40,000 and 60,000). The ribs were arranged in a staggered fashion between the upper and lower surfaces of the test section. Computational investigations are carried out using computational fluid dynamic software ANSYS Fluent 14.0. Suitable solver settings like turbulence models were identified from the literature and the boundary conditions for the simulations on a solution of independent grid. Computations were carried out for both convergent and divergent channels with 0 (smooth duct), 1.5, 3, 6, 9 and 12 mm rib heights, to identify the ribbed channel with optimal performance, assessed using a thermo hydraulic performance parameter. The convergent and divergent rectangular channels show higher Nu values than the standard correlation values.

  3. Numerical analysis of hydrodynamics in a rotor-stator reactor for biodiesel synthesis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wen, Zhuqing; Petera, Jerzy

    A rotor-stator spinning disk reactor for intensified biodiesel synthesis is described and numerically simulated. The reactor consists of two flat disks, located coaxially and parallel to each other with a gap ranging from 0.1 mm to 0.2 mm between the disks. The upper disk is located on a rotating shaft while the lower disk is stationary. The feed liquids, triglycerides (TG) and methanol are introduced coaxially along the center line of rotating disk and stationary disk, respectively. Fluid hydrodynamics in the reactor for synthesis of biodiesel from TG and methanol in the presence of a sodium hydroxide catalyst are simulated, using convection-diffusion-reactionmore » species transport model by the CFD software ANSYS©Fluent v. 13.0. The effects of upper disk’s spinning speed, gap size and flow rates at inlets are evaluated.« less

  4. Wood Combustion Behaviour in a Fixed Bed Combustor

    NASA Astrophysics Data System (ADS)

    Tokit, Ernie Mat; Aziz, Azhar Abdul; Ghazali, Normah Mohd

    2010-06-01

    Waste wood is used as feedstock for Universiti Teknologi Malaysia's newly-developed two-stage incinerator system. The research goals are to optimize the operation of the thermal system to the primary chamber, to improve its combustion efficiency and to minimize its pollutants formation. The combustion process is evaluated with the variation of fuel's moisture content. For optimum operating condition, where the gasification efficiency is 95.53%, the moisture content of the fuel is best set at 17%; giving outlet operating temperature of 550°C and exhaust gas concentrations with 1213 ppm of CO, 6% of CO2 and 14% of O2 respectively. In line to the experimental work, a computational fluid dynamics software, Fluent is used to simulate the performance of the primary chamber. Here the predicted optimum gasification efficiency stands at 95.49% with CO, CO2 and O2 concentrations as 1301 ppm, 6.5% and 13.5% respectively.

  5. Numerical study of the influence of flow blockage on the aerodynamic coefficients of models in low-speed wind tunnels

    NASA Astrophysics Data System (ADS)

    Bui, V. T.; Kalugin, V. T.; Lapygin, V. I.; Khlupnov, A. I.

    2017-11-01

    With the use of ANSYS Fluent software and ANSYS ICEM CFD calculation grid generator, the flows past a wing airfoil, an infinite cylinder, and 3D blunted bodies located in the open and closed test sections of low-speed wind tunnels were calculated. The mathematical model of the flows included the Reynolds equations and the SST model of turbulence. It was found that the ratios between the aerodynamic coefficients in the test section and in the free (unbounded) stream could be fairly well approximated with a piecewise-linear function of the blockage factor, whose value weakly depended on the angle of attack. The calculated data and data gained in the analysis of previously reported experimental studies proved to be in a good agreement. The impact of the extension of the closed test section on the airfoil lift force is analyzed.

  6. The influence of fuel type to combustion characteristic in diffusion flame drying by computational fluid dynamics simulation

    NASA Astrophysics Data System (ADS)

    Septiani, Eka Lutfi; Widiyastuti, W.; Machmudah, Siti; Nurtono, Tantular; Winardi, Sugeng

    2017-05-01

    Diffusion flame spray drying has become promising method in nanoparticles synthesis giving several advantages and low operation cost. In order to scale up the process which needs high experimentation time and cost, Computational Fluid Dynamics (CFD) by Ansys Fluent 15.0 software has been used. Combustion characteristic in diffusion flame reactor may affects particle size distribution. This study aims to observe influence of fuel type to combustion characteristic in the reactor. Large Eddy Simulation (LES) and non-premixed combustion model are selected for the turbulence and combustion model respectively. Methane, propane, and LPG in 0.5 L/min were used as type of fuel. While the oxidizer is air with 200% excess of O2. Simulation result shown that the maximum temperature was obtained from propane-air combustion in 2268 K. However, the stable temperature contour was achieved by methane-air combustion.

  7. Design and simulation of a novel high-efficiency cooling heat-sink structure using fluid-thermodynamics

    NASA Astrophysics Data System (ADS)

    Hongqi, Jing; Li, Zhong; Yuxi, Ni; Junjie, Zhang; Suping, Liu; Xiaoyu, Ma

    2015-10-01

    A novel high-efficiency cooling mini-channel heat-sink structure has been designed to meet the package technology demands of high power density laser diode array stacks. Thermal and water flowing characteristics have been simulated using the Ansys-Fluent software. Owing to the increased effective cooling area, this mini-channel heat-sink structure has a better cooling effect when compared with the traditional macro-channel heat-sinks. Owing to the lower flow velocity in this novel high efficient cooling structure, the chillers' water-pressure requirement is reduced. Meanwhile, the machining process of this high-efficiency cooling mini-channel heat-sink structure is simple and the cost is relatively low, it also has advantages in terms of high durability and long lifetime. This heat-sink is an ideal choice for the package of high power density laser diode array stacks. Project supported by the Defense Industrial Technology Development Program (No. B1320133033).

  8. A computerized procedure for teaching the relationship between graphic symbols and their referents.

    PubMed

    Isaacson, Mick; Lloyd, Lyle L

    2013-01-01

    Many individuals with little or no functional speech communicate through graphic symbols. Communication is enhanced when the relationship between symbols and their referents are learned to such a degree that retrieval is effortless, resulting in fluent communication. Developing fluency is a time consuming endeavor for special educators and speech-language pathologists (SLPs). It would be beneficial for these professionals to have an automated procedure based on the most efficacious method for teaching the relationship between symbols and referent. Hence, this study investigated whether a procedure based on the generation effect would promote learning the association between symbols and their referents. Results show that referent generation produces the best long-term retention of this relationship. These findings provide evidence that software based on referent generation would provide special educators and SLPs with an efficacious automated procedure, requiring minimal direct supervision, to facilitate symbol/referent learning and the development of communicative fluency.

  9. Re-Purposing Commercial Entertainment Software for Military Use

    DTIC Science & Technology

    2000-09-01

    and simulation needs of the military can be awkward or impossible. Video games are designed to be both technologically advanced and flexible in design...We evaluated current games and modified Quake 3 Arena(Q3A) to serve as both an architectural walkthrough and a primitive team trainer. To accomplish...weapons models and characteristics, and overall game play. By re-purposing commercial entertainment software, we have produced a viable military virtual

  10. Characterization of a commercial software defined radio as high frequency lock-in amplifier for FM spectroscopy.

    PubMed

    Mahnke, Peter

    2018-01-01

    A commercial software defined radio based on a Rafael Micro R820T2 tuner is characterized for the use as a high-frequency lock-in amplifier for frequency modulation spectroscopy. The sensitivity limit of the receiver is 1.6 nV/Hz. Frequency modulation spectroscopy is demonstrated on the 6406.69 cm -1 absorption line of carbon monoxide.

  11. Characterization of a commercial software defined radio as high frequency lock-in amplifier for FM spectroscopy

    NASA Astrophysics Data System (ADS)

    Mahnke, Peter

    2018-01-01

    A commercial software defined radio based on a Rafael Micro R820T2 tuner is characterized for the use as a high-frequency lock-in amplifier for frequency modulation spectroscopy. The sensitivity limit of the receiver is 1.6 nV/√{Hz }. Frequency modulation spectroscopy is demonstrated on the 6406.69 cm-1 absorption line of carbon monoxide.

  12. Assessing the Content and Quality of Commercially Available Reading Software Programs: Do They Have the Fundamental Structures to Promote the Development of Early Reading Skills in Children?

    ERIC Educational Resources Information Center

    Grant, Amy; Wood, Eileen; Gottardo, Alexandra; Evans, Mary Ann; Phillips, Linda; Savage, Robert

    2012-01-01

    The current study developed a taxonomy of reading skills and compared this taxonomy with skills being trained in 30 commercially available software programs designed to teach emergent literacy or literacy-specific skills for children in preschool, kindergarten, and Grade 1. Outcomes suggest that, although some skills are being trained in a…

  13. Flexible control techniques for a lunar base

    NASA Technical Reports Server (NTRS)

    Kraus, Thomas W.

    1992-01-01

    The fundamental elements found in every terrestrial control system can be employed in all lunar applications. These elements include sensors which measure physical properties, controllers which acquire sensor data and calculate a control response, and actuators which apply the control output to the process. The unique characteristics of the lunar environment will certainly require the development of new control system technology. However, weightlessness, harsh atmospheric conditions, temperature extremes, and radiation hazards will most significantly impact the design of sensors and actuators. The controller and associated control algorithms, which are the most complex element of any control system, can be derived in their entirety from existing technology. Lunar process control applications -- ranging from small-scale research projects to full-scale processing plants -- will benefit greatly from the controller advances being developed today. In particular, new software technology aimed at commercial process monitoring and control applications will almost completely eliminate the need for custom programs and the lengthy development and testing cycle they require. The applicability of existing industrial software to lunar applications has other significant advantages in addition to cost and quality. This software is designed to run on standard hardware platforms and takes advantage of existing LAN and telecommunications technology. Further, in order to exploit the existing commercial market, the software is being designed to be implemented by users of all skill levels -- typically users who are familiar with their process, but not necessarily with software or control theory. This means that specialized technical support personnel will not need to be on-hand, and the associated costs are eliminated. Finally, the latest industrial software designed for the commercial market is extremely flexible, in order to fit the requirements of many types of processing applications with little or no customization. This means that lunar process control projects will not be delayed by unforeseen problems or last minute process modifications. The software will include all of the tools needed to adapt to virtually any changes. In contrast to other space programs which required the development of tremendous amounts of custom software, lunar-based processing facilities will benefit from the use of existing software technology which is being proven in commercial applications on Earth.

  14. Enhanced Visualization of Subtle Outer Retinal Pathology by En Face Optical Coherence Tomography and Correlation with Multi-Modal Imaging

    PubMed Central

    Chew, Avenell L.; Lamey, Tina; McLaren, Terri; De Roach, John

    2016-01-01

    Purpose To present en face optical coherence tomography (OCT) images generated by graph-search theory algorithm-based custom software and examine correlation with other imaging modalities. Methods En face OCT images derived from high density OCT volumetric scans of 3 healthy subjects and 4 patients using a custom algorithm (graph-search theory) and commercial software (Heidelberg Eye Explorer software (Heidelberg Engineering)) were compared and correlated with near infrared reflectance, fundus autofluorescence, adaptive optics flood-illumination ophthalmoscopy (AO-FIO) and microperimetry. Results Commercial software was unable to generate accurate en face OCT images in eyes with retinal pigment epithelium (RPE) pathology due to segmentation error at the level of Bruch’s membrane (BM). Accurate segmentation of the basal RPE and BM was achieved using custom software. The en face OCT images from eyes with isolated interdigitation or ellipsoid zone pathology were of similar quality between custom software and Heidelberg Eye Explorer software in the absence of any other significant outer retinal pathology. En face OCT images demonstrated angioid streaks, lesions of acute macular neuroretinopathy, hydroxychloroquine toxicity and Bietti crystalline deposits that correlated with other imaging modalities. Conclusions Graph-search theory algorithm helps to overcome the limitations of outer retinal segmentation inaccuracies in commercial software. En face OCT images can provide detailed topography of the reflectivity within a specific layer of the retina which correlates with other forms of fundus imaging. Our results highlight the need for standardization of image reflectivity to facilitate quantification of en face OCT images and longitudinal analysis. PMID:27959968

  15. Analysis of a hydraulic a scaled asymmetric labyrinth weir with Ansys-Fluent

    NASA Astrophysics Data System (ADS)

    Otálora Carmona, Andrés Humberto; Santos Granados, Germán Ricardo

    2017-04-01

    This document presents the three dimensional computational modeling of a labyrinth weir, using the version 17.0 of the Computational Fluid Dynamics (CFD) software ANSYS - FLUENT. The computational characteristics of the model such as the geometry consideration, the mesh sensitivity, the numerical scheme, and the turbulence modeling parameters. The volume fraction of the water mixture - air, the velocity profile, the jet trajectory, the discharge coefficient and the velocity field are analyzed. With the purpose of evaluating the hydraulic behavior of the labyrinth weir of the Naveta's hydroelectric, in Apulo - Cundinamarca, was development a 1:21 scale model of the original structure, which was tested in the laboratory of the hydraulic studies in the Escuela Colombiana de Ingeniería Julio Garavito. The scale model of the structure was initially developed to determine the variability of the discharge coefficient with respect to the flow rate and their influence on the water level. It was elaborate because the original weir (labyrinth weir with not symmetrical rectangular section), did not have the capacity to work with the design flow of 31 m3/s, because over 15 m3/s, there were overflows in the adduction channel. This variation of efficiency was due to the thickening of the lateral walls by structural requirements. During the physical modeling doing by Rodríguez, H. and Matamoros H. (2015) in the test channel, it was found that, with the increase in the width of the side walls, the discharge coefficient is reduced an average by 34%, generating an increase of the water level by 0.26 m above the structure. This document aims to develop a splicing methodology between the physical models of a labyrinth weir and numerical modeling, using concepts of computational fluid dynamics and finite volume theories. For this, was carried out a detailed analysis of the variations in the different directions of the main hydraulic variables involved in the behavior, such as, the components of the velocity and the distribution of pressures, For the numerical development, we worked with ANSYS - FLUENT software modeling version 17.0. Initially, a digital model of a conventional triangular weir with a vertical angle of 102° was developed in order to find the most appropriate numerical scheme and conditions. The numerical results were compared with conventional theories, evaluating the path and discharge coefficient. Subsequently, one of the five cycles that compose the labyrinth weir was simulated, evaluating the behavior of the discharge coefficient, the water level, the streamline and the velocity field, with the purpose of understanding the hydraulic variables that are related in these geometries. According to the previous results, the numerical modeling of labyrinth weir was performed, comparing the obtained results with the data of the physical scale model, analyzing the variation of the discharge coefficient, the streamline, velocity field, pressure distribution and shear stress. Finally, based on the lessons learned from physical and numerical modeling, a methodological guide was created for any user with a computational and hydraulic fluid mechanics knowledge to develop a good practice of a computational and physical modeling.

  16. Verification of ANSYS Fluent and OpenFOAM CFD platforms for prediction of impact flow

    NASA Astrophysics Data System (ADS)

    Tisovská, Petra; Peukert, Pavel; Kolář, Jan

    The main goal of the article is a verification of the heat transfer coefficient numerically predicted by two CDF platforms - ANSYS-Fluent and OpenFOAM on the problem of impact flows oncoming from 2D nozzle. Various mesh parameters and solver settings were tested under several boundary conditions and compared to known experimental results. The best solver setting, suitable for further optimization of more complex geometry is evaluated.

  17. Investigation of computational aeroacoustic tools for noise predictions of wind turbine aerofoils

    NASA Astrophysics Data System (ADS)

    Humpf, A.; Ferrer, E.; Munduate, X.

    2007-07-01

    In this work trailing edge noise levels of a research aerofoil have been computed and compared to aeroacoustic measurements using two different approaches. On the other hand, aerodynamic and aeroacoustic calculations were performed with the full Navier-Stokes CFD code Fluent [Fluent Inc 2005 Fluent 6.2 Users Guide, Lebanon, NH, USA] on the basis of a steady RANS simulation. Aerodynamic characteristics were computed by the aid of various turbulence models. By the combined usage of implemented broadband noise source models, it was tried to isolate and determine the trailing edge noise level. Throughout this work two methods of different computational cost have been tested and quantitative and qualitative results obtained. On the one hand, the semi-empirical noise prediction tool NAFNoise [Moriarty P 2005 NAFNoise User's Guide. Golden, Colorado, July. http://wind.nrel.gov/designcodes/ simulators/NAFNoise] was used to directly predict trailing edge noise by taking into consideration the nature of the experiments.

  18. How fluent is the fluent speech of people who stutter? A new approach to measuring kinematics with ultrasound.

    PubMed

    Heyde, Cornelia J; Scobbie, James M; Lickley, Robin; Drake, Eleanor K E

    2016-01-01

    We present a new approach to the investigation of dynamic ultrasound tongue imaging (UTI) data, applied here to analyse the subtle aspects of the fluency of people who stutter (PWS). Fluent productions of CV syllables (C = /k/; V = /ɑ, i, ə/) from three PWS and three control speakers (PNS) were analysed for duration and peak velocity relative to articulatory movement towards (onset) and away from (offset) the consonantal closure. The objective was to apply a replicable methodology for kinematic investigation to speech of PWS in order to test Wingate's Fault-Line hypothesis. As was hypothesised, results show comparable onset behaviours for both groups. Regarding offsets, groups differ in peak velocity. Results suggest that PWS do not struggle initiating consonantal closure (onset). In transition from consonantal closure into the vowel, however, groups appear to employ different strategies expressed in increased variation (PNS) versus decreased mean peak velocity (PWS).

  19. Early-stage chunking of finger tapping sequences by persons who stutter and fluent speakers.

    PubMed

    Smits-Bandstra, Sarah; De Nil, Luc F

    2013-01-01

    This research note explored the hypothesis that chunking differences underlie the slow finger-tap sequencing performance reported in the literature for persons who stutter (PWS) relative to fluent speakers (PNS). Early-stage chunking was defined as an immediate and spontaneous tendency to organize a long sequence into pauses, for motor planning, and chunks of fluent motor performance. A previously published study in which 12 PWS and 12 matched PNS practised a 10-item finger tapping sequence 30 times was examined. Both groups significantly decreased the duration of between-chunk intervals (BCIs) and within-chunk intervals (WCIs) over practice. PNS had significantly shorter WCIs relative to PWS, but minimal differences between groups were found for the number of, or duration of, BCI. Results imply that sequencing differences found between PNS and PWS may be due to differences in automatizing movements within chunks or retrieving chunks from memory rather than chunking per se.

  20. Teacher-Designed Software for Interactive Linear Equations: Concepts, Interpretive Skills, Applications & Word-Problem Solving.

    ERIC Educational Resources Information Center

    Lawrence, Virginia

    No longer just a user of commercial software, the 21st century teacher is a designer of interactive software based on theories of learning. This software, a comprehensive study of straightline equations, enhances conceptual understanding, sketching, graphic interpretive and word problem solving skills as well as making connections to real-life and…

  1. COTS-based OO-component approach for software inter-operability and reuse (software systems engineering methodology)

    NASA Technical Reports Server (NTRS)

    Yin, J.; Oyaki, A.; Hwang, C.; Hung, C.

    2000-01-01

    The purpose of this research and study paper is to provide a summary description and results of rapid development accomplishments at NASA/JPL in the area of advanced distributed computing technology using a Commercial-Off--The-Shelf (COTS)-based object oriented component approach to open inter-operable software development and software reuse.

  2. Features of commercial computer software systems for medical examiners and coroners.

    PubMed

    Hanzlick, R L; Parrish, R G; Ing, R

    1993-12-01

    There are many ways of automating medical examiner and coroner offices, one of which is to purchase commercial software products specifically designed for death investigation. We surveyed four companies that offer such products and requested information regarding each company and its hardware, software, operating systems, peripheral devices, applications, networking options, programming language, querying capability, coding systems, prices, customer support, and number and size of offices using the product. Although the four products (CME2, ForenCIS, InQuest, and Medical Examiner's Software System) are similar in many respects and each can be installed on personal computers, there are differences among the products with regard to cost, applications, and the other features. Death investigators interested in office automation should explore these products to determine the usefulness of each in comparison with the others and in comparison with general-purpose, off-the-shelf databases and software adaptable to death investigation needs.

  3. 10 CFR 603.550 - Acceptability of intellectual property.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... property (e.g., copyrighted material, including software) as cost sharing because: (1) It is difficult to... the contribution. For example, a for-profit firm may offer the use of commercially available software... the software would not be a reasonable basis for valuing its use. ...

  4. 10 CFR 603.550 - Acceptability of intellectual property.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... property (e.g., copyrighted material, including software) as cost sharing because: (1) It is difficult to... the contribution. For example, a for-profit firm may offer the use of commercially available software... the software would not be a reasonable basis for valuing its use. ...

  5. Bar-Code System for a Microbiological Laboratory

    NASA Technical Reports Server (NTRS)

    Law, Jennifer; Kirschner, Larry

    2007-01-01

    A bar-code system has been assembled for a microbiological laboratory that must examine a large number of samples. The system includes a commercial bar-code reader, computer hardware and software components, plus custom-designed database software. The software generates a user-friendly, menu-driven interface.

  6. A high-speed linear algebra library with automatic parallelism

    NASA Technical Reports Server (NTRS)

    Boucher, Michael L.

    1994-01-01

    Parallel or distributed processing is key to getting highest performance workstations. However, designing and implementing efficient parallel algorithms is difficult and error-prone. It is even more difficult to write code that is both portable to and efficient on many different computers. Finally, it is harder still to satisfy the above requirements and include the reliability and ease of use required of commercial software intended for use in a production environment. As a result, the application of parallel processing technology to commercial software has been extremely small even though there are numerous computationally demanding programs that would significantly benefit from application of parallel processing. This paper describes DSSLIB, which is a library of subroutines that perform many of the time-consuming computations in engineering and scientific software. DSSLIB combines the high efficiency and speed of parallel computation with a serial programming model that eliminates many undesirable side-effects of typical parallel code. The result is a simple way to incorporate the power of parallel processing into commercial software without compromising maintainability, reliability, or ease of use. This gives significant advantages over less powerful non-parallel entries in the market.

  7. Evaluation of the finite element software ABAQUS for biomechanical modelling of biphasic tissues.

    PubMed

    Wu, J Z; Herzog, W; Epstein, M

    1998-02-01

    The biphasic cartilage model proposed by Mow et al. (1980) has proven successful to capture the essential mechanical features of articular cartilage. In order to analyse the joint contact mechanics in real, anatomical joints, the cartilage model needs to be implemented into a suitable finite element code to approximate the irregular surface geometries of such joints. However, systematic and extensive evaluation of the capacity of commercial software for modelling the contact mechanics with biphasic cartilage layers has not been made. This research was aimed at evaluating the commercial finite element software ABAQUS for analysing biphasic soft tissues. The solutions obtained using ABAQUS were compared with those obtained using other finite element models and analytical solutions for three numerical tests: an unconfined indentation test, a test with the contact of a spherical cartilage surface with a rigid plate, and an axi-symmetric joint contact test. It was concluded that the biphasic cartilage model can be implemented into the commercial finite element software ABAQUS to analyse practical joint contact problems with biphasic articular cartilage layers.

  8. Commercial Skills Test Information Management System final report and self-sustainability plan : [technology brief].

    DOT National Transportation Integrated Search

    2014-04-01

    The Commercial Skills Test Information Management System (CSTIMS) was developed to address the fraudulent issuance of commercial drivers licenses (CDLs) across the United States. CSTIMS was developed as a Web-based, software-as-a-service system to...

  9. Production, formulation and cost estimation of a commercial biosurfactant.

    PubMed

    Soares da Silva, Rita de Cássia Freire; de Almeida, Darne Germano; Brasileiro, Pedro Pinto Ferreira; Rufino, Raquel Diniz; de Luna, Juliana Moura; Sarubbo, Leonie Asfora

    2018-05-03

    Due to their amphipathic nature, biosurfactants are multifunctional molecules that have considerable potential in several industries, especially the petroleum industry. In this study, the commercial production of a biosurfactant from Pseudomonas cepacia CCT6659 grown on industrial waste was investigated in a semi-industrial 50-L bioreactor for use in the removal of hydrocarbons from oily effluents. A concentration of 40.5 g/L was achieved in the scale up and the surface tension was reduced to 29 mN/m. The biosurfactant was formulated with an added preservative, tyndallization and the combination of fluent vaporization plus the preservative. Formulated biosurfactant samples were stored for 120 days. Tensioactive properties and stability were evaluated with different pH values, temperatures and salt concentrations. The commercial biosurfactant obtained with all formulation methods demonstrated good stability, with tolerance to a wide range of pH values as well as high temperature and high salinity, enabling application in extreme environmental conditions, as it occurs in industrial plants. The biosurfactant proved to be economically viable for large-scale application, as demonstrated by the cost of the product, estimated at around US$ 0.14-0.15/L and US$ 0.02/g for the formulated and the isolated biosurfactant, respectively. Both products were applied in an oil-fired thermoelectric plant for the treatment of oily effluents and removed up to 100% of the oil. Therefore, this biosurfactant is suitable for application under extreme conditions, such as in the petroleum industry, and can be produced at a more attractive price compared to other commercially available products on the market.

  10. Eric Bonnema | NREL

    Science.gov Websites

    contributes to the research efforts for commercial buildings. This effort is dedicated to studying the , commercial sector whole-building energy simulation, scientific computing, and software configuration and

  11. Development and Analysis of a Bi-Directional Tidal Turbine

    DTIC Science & Technology

    2012-03-01

    commercial CFD software ANSYS CFX was utilized to build a turbine map. The basic turbine map was developed for a 25 blade bi-axial turbine under...directional turbine created for this purpose. In the present study, the commercial CFD software ANSYS CFX was utilized to build a turbine map. The...sheath C. PROBLEM SPECIFICATIONS AND BOUNDARY CONDITIONS The simulation definition was created using ANSYS CFX -Pre. The best measurements to determine

  12. A Randomised Controlled Trial of the Use of a Piece of Commercial Software for the Acquisition of Reading Skills

    ERIC Educational Resources Information Center

    Khan, Muhammad Ahmad; Gorard, Stephen

    2012-01-01

    We report here the overall results of a cluster randomised controlled trial of the use of computer-aided instruction with 672 Year 7 pupils in 23 secondary school classes in the north of England. A new piece of commercial software, claimed on the basis of publisher testing to be effective in improving reading after just six weeks of use in the…

  13. Commercial Digital/ADP Equipment in the Ocean Environment. Volume 2. User Appendices

    DTIC Science & Technology

    1978-12-15

    is that the LINDA system uses a mini computer with a time sharing system software which allows several terminals to be operated at the same time...Acquisition System (ODAS) consists of sensors, computer hardware and computer software . Certain sensors are interfaced to the computers for real time...on USNS KANE, USNS BENT, and USKS WILKES. Commercial automatic data processing equipment used in ODAS includes: Item Model Computer PDP-9 Tape

  14. Caltech/JPL Conference on Image Processing Technology, Data Sources and Software for Commercial and Scientific Applications

    NASA Technical Reports Server (NTRS)

    Redmann, G. H.

    1976-01-01

    Recent advances in image processing and new applications are presented to the user community to stimulate the development and transfer of this technology to industrial and commercial applications. The Proceedings contains 37 papers and abstracts, including many illustrations (some in color) and provides a single reference source for the user community regarding the ordering and obtaining of NASA-developed image-processing software and science data.

  15. Arbitrating Control of Control and Display Units

    NASA Technical Reports Server (NTRS)

    Sugden, Paul C.

    2007-01-01

    The ARINC 739 Switch is a computer program that arbitrates control of two multi-function control and display units (MCDUs) between (1) a commercial flight-management computer (FMC) and (2) NASA software used in research on transport aircraft. (MCDUs are the primary interfaces between pilots and FMCs on many commercial aircraft.) This program was recently redesigned into a software library that can be embedded in research application programs. As part of the redesign, this software was combined with software for creating custom pages of information to be displayed on a CDU. This software commands independent switching of the left (pilot s) and right (copilot s) MCDUs. For example, a custom CDU page can control the left CDU while the FMC controls the right CDU. The software uses menu keys to switch control of the CDU between the FMC or a custom CDU page. The software provides an interface that enables custom CDU pages to insert keystrokes into the FMC s CDU input interface. This feature allows the custom CDU pages to manipulate the FMC as if it were a pilot.

  16. Supervised Semi-Automated Data Analysis Software for Gas Chromatography / Differential Mobility Spectrometry (GC/DMS) Metabolomics Applications.

    PubMed

    Peirano, Daniel J; Pasamontes, Alberto; Davis, Cristina E

    2016-09-01

    Modern differential mobility spectrometers (DMS) produce complex and multi-dimensional data streams that allow for near-real-time or post-hoc chemical detection for a variety of applications. An active area of interest for this technology is metabolite monitoring for biological applications, and these data sets regularly have unique technical and data analysis end user requirements. While there are initial publications on how investigators have individually processed and analyzed their DMS metabolomic data, there are no user-ready commercial or open source software packages that are easily used for this purpose. We have created custom software uniquely suited to analyze gas chromatograph / differential mobility spectrometry (GC/DMS) data from biological sources. Here we explain the implementation of the software, describe the user features that are available, and provide an example of how this software functions using a previously-published data set. The software is compatible with many commercial or home-made DMS systems. Because the software is versatile, it can also potentially be used for other similarly structured data sets, such as GC/GC and other IMS modalities.

  17. Customizing graphical user interface technology for spacecraft control centers

    NASA Technical Reports Server (NTRS)

    Beach, Edward; Giancola, Peter; Gibson, Steven; Mahmot, Ronald

    1993-01-01

    The Transportable Payload Operations Control Center (TPOCC) project is applying the latest in graphical user interface technology to the spacecraft control center environment. This project of the Mission Operations Division's (MOD) Control Center Systems Branch (CCSB) at NASA Goddard Space Flight Center (GSFC) has developed an architecture for control centers which makes use of a distributed processing approach and the latest in Unix workstation technology. The TPOCC project is committed to following industry standards and using commercial off-the-shelf (COTS) hardware and software components wherever possible to reduce development costs and to improve operational support. TPOCC's most successful use of commercial software products and standards has been in the development of its graphical user interface. This paper describes TPOCC's successful use and customization of four separate layers of commercial software products to create a flexible and powerful user interface that is uniquely suited to spacecraft monitoring and control.

  18. The impact of impaired semantic knowledge on spontaneous iconic gesture production

    PubMed Central

    Cocks, Naomi; Dipper, Lucy; Pritchard, Madeleine; Morgan, Gary

    2013-01-01

    Background Previous research has found that people with aphasia produce more spontaneous iconic gesture than control participants, especially during word-finding difficulties. There is some evidence that impaired semantic knowledge impacts on the diversity of gestural handshapes, as well as the frequency of gesture production. However, no previous research has explored how impaired semantic knowledge impacts on the frequency and type of iconic gestures produced during fluent speech compared with those produced during word-finding difficulties. Aims To explore the impact of impaired semantic knowledge on the frequency and type of iconic gestures produced during fluent speech and those produced during word-finding difficulties. Methods & Procedures A group of 29 participants with aphasia and 29 control participants were video recorded describing a cartoon they had just watched. All iconic gestures were tagged and coded as either “manner,” “path only,” “shape outline” or “other”. These gestures were then separated into either those occurring during fluent speech or those occurring during a word-finding difficulty. The relationships between semantic knowledge and gesture frequency and form were then investigated in the two different conditions. Outcomes & Results As expected, the participants with aphasia produced a higher frequency of iconic gestures than the control participants, but when the iconic gestures produced during word-finding difficulties were removed from the analysis, the frequency of iconic gesture was not significantly different between the groups. While there was not a significant relationship between the frequency of iconic gestures produced during fluent speech and semantic knowledge, there was a significant positive correlation between semantic knowledge and the proportion of word-finding difficulties that contained gesture. There was also a significant positive correlation between the speakers' semantic knowledge and the proportion of gestures that were produced during fluent speech that were classified as “manner”. Finally while not significant, there was a positive trend between semantic knowledge of objects and the production of “shape outline” gestures during word-finding difficulties for objects. Conclusions The results indicate that impaired semantic knowledge in aphasia impacts on both the iconic gestures produced during fluent speech and those produced during word-finding difficulties but in different ways. These results shed new light on the relationship between impaired language and iconic co-speech gesture production and also suggest that analysis of iconic gesture may be a useful addition to clinical assessment. PMID:24058228

  19. 48 CFR 209.505-4 - Obtaining access to proprietary information.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...) For contractors accessing third party proprietary technical data or computer software, non-disclosure... limited rights technical data, commercial technical data, or restricted rights computer software. The...

  20. Software Graphics Processing Unit (sGPU) for Deep Space Applications

    NASA Technical Reports Server (NTRS)

    McCabe, Mary; Salazar, George; Steele, Glen

    2015-01-01

    A graphics processing capability will be required for deep space missions and must include a range of applications, from safety-critical vehicle health status to telemedicine for crew health. However, preliminary radiation testing of commercial graphics processing cards suggest they cannot operate in the deep space radiation environment. Investigation into an Software Graphics Processing Unit (sGPU)comprised of commercial-equivalent radiation hardened/tolerant single board computers, field programmable gate arrays, and safety-critical display software shows promising results. Preliminary performance of approximately 30 frames per second (FPS) has been achieved. Use of multi-core processors may provide a significant increase in performance.

  1. The look of LaTeX

    NASA Astrophysics Data System (ADS)

    This has always been the major objection to its use by those not driven by the need to typeset mathematics since the “what-you-see-is-what-you-get” (WYSIWYG) packages offered by Microsoft Word and WordPerfect are easy to learn and use. Recently, however, com-mercial software companies have begun to market almost-WYSIWYG programs that create LaTeX files. Some commercial software that creates LaTeX files are listed in Table 1. EXP and SWP have some of the “look and feel” of the software that is popular in offices and PCTeX32 allows quick and convenient previews of the translated LaTeX files.

  2. Structural Analysis and Design Software

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Collier Research and Development Corporation received a one-of-a-kind computer code for designing exotic hypersonic aircraft called ST-SIZE in the first ever Langley Research Center software copyright license agreement. Collier transformed the NASA computer code into a commercial software package called HyperSizer, which integrates with other Finite Element Modeling and Finite Analysis private-sector structural analysis program. ST-SIZE was chiefly conceived as a means to improve and speed the structural design of a future aerospace plane for Langley Hypersonic Vehicles Office. Including the NASA computer code into HyperSizer has enabled the company to also apply the software to applications other than aerospace, including improved design and construction for offices, marine structures, cargo containers, commercial and military aircraft, rail cars, and a host of everyday consumer products.

  3. Computer and control applications in a vegetable processing plant

    USDA-ARS?s Scientific Manuscript database

    There are many advantages to the use of computers and control in food industry. Software in the food industry takes 2 forms - general purpose commercial computer software and software for specialized applications, such as drying and thermal processing of foods. Many applied simulation models for d...

  4. Design study of Software-Implemented Fault-Tolerance (SIFT) computer

    NASA Technical Reports Server (NTRS)

    Wensley, J. H.; Goldberg, J.; Green, M. W.; Kutz, W. H.; Levitt, K. N.; Mills, M. E.; Shostak, R. E.; Whiting-Okeefe, P. M.; Zeidler, H. M.

    1982-01-01

    Software-implemented fault tolerant (SIFT) computer design for commercial aviation is reported. A SIFT design concept is addressed. Alternate strategies for physical implementation are considered. Hardware and software design correctness is addressed. System modeling and effectiveness evaluation are considered from a fault-tolerant point of view.

  5. Application of the airborne ocean color imager for commercial fishing

    NASA Technical Reports Server (NTRS)

    Wrigley, Robert C.

    1993-01-01

    The objective of the investigation was to develop a commercial remote sensing system for providing near-real-time data (within one day) in support of commercial fishing operations. The Airborne Ocean Color Imager (AOCI) had been built for NASA by Daedalus Enterprises, Inc., but it needed certain improvements, data processing software, and a delivery system to make it into a commercial system for fisheries. Two products were developed to support this effort: the AOCI with its associated processing system and an information service for both commercial and recreational fisheries to be created by Spectro Scan, Inc. The investigation achieved all technical objectives: improving the AOCI, creating software for atmospheric correction and bio-optical output products, georeferencing the output products, and creating a delivery system to get those products into the hands of commercial and recreational fishermen in near-real-time. The first set of business objectives involved Daedalus Enterprises and also were achieved: they have an improved AOCI and new data processing software with a set of example data products for fisheries applications to show their customers. Daedalus' marketing activities showed the need for simplification of the product for fisheries, but they successfully marketed the current version to an Italian consortium. The second set of business objectives tasked Spectro Scan to provide an information service and they could not be achieved because Spectro Scan was unable to obtain necessary venture capital to start up operations.

  6. Evolving software reengineering technology for the emerging innovative-competitive era

    NASA Technical Reports Server (NTRS)

    Hwang, Phillip Q.; Lock, Evan; Prywes, Noah

    1994-01-01

    This paper reports on a multi-tool commercial/military environment combining software Domain Analysis techniques with Reusable Software and Reengineering of Legacy Software. It is based on the development of a military version for the Department of Defense (DOD). The integrated tools in the military version are: Software Specification Assistant (SSA) and Software Reengineering Environment (SRE), developed by Computer Command and Control Company (CCCC) for Naval Surface Warfare Center (NSWC) and Joint Logistics Commanders (JLC), and the Advanced Research Project Agency (ARPA) STARS Software Engineering Environment (SEE) developed by Boeing for NAVAIR PMA 205. The paper describes transitioning these integrated tools to commercial use. There is a critical need for the transition for the following reasons: First, to date, 70 percent of programmers' time is applied to software maintenance. The work of these users has not been facilitated by existing tools. The addition of Software Reengineering will also facilitate software maintenance and upgrading. In fact, the integrated tools will support the entire software life cycle. Second, the integrated tools are essential to Business Process Reengineering, which seeks radical process innovations to achieve breakthrough results. Done well, process reengineering delivers extraordinary gains in process speed, productivity and profitability. Most importantly, it discovers new opportunities for products and services in collaboration with other organizations. Legacy computer software must be changed rapidly to support innovative business processes. The integrated tools will provide commercial organizations important competitive advantages. This, in turn, will increase employment by creating new business opportunities. Third, the integrated system will produce much higher quality software than use of the tools separately. The reason for this is that producing or upgrading software requires keen understanding of extremely complex applications which is facilitated by the integrated tools. The radical savings in the time and cost associated with software, due to use of CASE tools that support combined Reuse of Software and Reengineering of Legacy Code, will add an important impetus to improving the automation of enterprises. This will be reflected in continuing operations, as well as in innovating new business processes. The proposed multi-tool software development is based on state of the art technology, which will be further advanced through the use of open systems for adding new tools and experience in their use.

  7. Differences of Articulation Rate and Utterance Length in Fluent and Disfluent Utterances of Preschool Children Who Stutter

    PubMed Central

    Chon, HeeCheong; Sawyer, Jean; Ambrose, Nicoline G.

    2014-01-01

    Purpose The purpose of this study was to investigate characteristics of four types of utterances in preschool children who stutter: perceptually fluent, containing normal disfluencies (OD utterance), containing stuttering-like disfluencies (SLD utterance), and containing both normal and stuttering-like disfluencies (SLD+OD utterance). Articulation rate and length of utterance were measured to seek the differences. Because articulation rate may reflect temporal aspects of speech motor control, it was predicted that the articulation rate would be different between perceptually fluent utterances and utterances containing disfluencies. The length of utterance was also expected to show different patterns. Method Participants were 14 preschool children who stutter. Disfluencies were identified from their spontaneous speech samples, and articulation rate in syllables per second and utterance length in syllables were measured for the four types of utterances. Results and discussion There was no significant difference in articulation rate between each type of utterance. Significantly longer utterances were found only in SLD+OD utterances compared to fluent utterances, suggesting that utterance length may be related to efforts in executing motor as well as linguistic planning. The SLD utterance revealed a significant negative correlation in that longer utterances tended to be slower in articulation rates. Longer utterances may place more demand on speech motor control due to more linguistic and/or grammatical features, resulting in stuttering-like disfluencies and a decreased rate. PMID:22995336

  8. Phonation interval modification and speech performance quality during fluency-inducing conditions by adults who stutter

    PubMed Central

    Ingham, Roger J.; Bothe, Anne K.; Wang, Yuedong; Purkhiser, Krystal; New, Anneliese

    2012-01-01

    Purpose To relate changes in four variables previously defined as characteristic of normally fluent speech to changes in phonatory behavior during oral reading by persons who stutter (PWS) and normally fluent controls under multiple fluency-inducing (FI) conditions. Method Twelve PWS and 12 controls each completed 4 ABA experiments. During A phases, participants read normally. B phases were 4 different FI conditions: auditory masking, chorus reading, whispering, and rhythmic stimulation. Dependent variables were the durations of accelerometer-recorded phonated intervals; self-judged speech effort; and observer-judged stuttering frequency, speech rate, and speech naturalness. The method enabled a systematic replication of Ingham et al. (2009). Results All FI conditions resulted in decreased stuttering and decreases in the number of short phonated intervals, as compared with baseline conditions, but the only FI condition that satisfied all four characteristics of normally fluent speech was chorus reading. Increases in longer phonated intervals were associated with decreased stuttering but also with poorer naturalness and/or increased speech effort. Previous findings concerning the effects of FI conditions on speech naturalness and effort were replicated. Conclusions Measuring all relevant characteristics of normally fluent speech, in the context of treatments that aim to reduce the occurrence of short-duration PIs, may aid the search for an explanation of the nature of stuttering and may also maximize treatment outcomes for adults who stutter. PMID:22365886

  9. Six pitfalls in firewall deployment

    NASA Astrophysics Data System (ADS)

    Wilner, Bruce

    1996-03-01

    This note describes six key pitfalls in the deployment of popular commercial firewalls. The term `deployment' is intended to include the architecture of the firewall software itself, the integration of the firewall with the operating system platform, and the interconnection of the complete hardware/software combination within its target environment. After reviewing the evolution of Internet firewalls against the backdrop of classical trusted systems development, specific flaws and oversights in the familiar commercial deployments are analyzed in some detail. While significantly costlier solutions are available that address some of these problems, the analysis is applicable to the overwhelming majority of firewalls in use at both commercial and Government installations.

  10. Buying in to bioinformatics: an introduction to commercial sequence analysis software

    PubMed Central

    2015-01-01

    Advancements in high-throughput nucleotide sequencing techniques have brought with them state-of-the-art bioinformatics programs and software packages. Given the importance of molecular sequence data in contemporary life science research, these software suites are becoming an essential component of many labs and classrooms, and as such are frequently designed for non-computer specialists and marketed as one-stop bioinformatics toolkits. Although beautifully designed and powerful, user-friendly bioinformatics packages can be expensive and, as more arrive on the market each year, it can be difficult for researchers, teachers and students to choose the right software for their needs, especially if they do not have a bioinformatics background. This review highlights some of the currently available and most popular commercial bioinformatics packages, discussing their prices, usability, features and suitability for teaching. Although several commercial bioinformatics programs are arguably overpriced and overhyped, many are well designed, sophisticated and, in my opinion, worth the investment. If you are just beginning your foray into molecular sequence analysis or an experienced genomicist, I encourage you to explore proprietary software bundles. They have the potential to streamline your research, increase your productivity, energize your classroom and, if anything, add a bit of zest to the often dry detached world of bioinformatics. PMID:25183247

  11. Buying in to bioinformatics: an introduction to commercial sequence analysis software.

    PubMed

    Smith, David Roy

    2015-07-01

    Advancements in high-throughput nucleotide sequencing techniques have brought with them state-of-the-art bioinformatics programs and software packages. Given the importance of molecular sequence data in contemporary life science research, these software suites are becoming an essential component of many labs and classrooms, and as such are frequently designed for non-computer specialists and marketed as one-stop bioinformatics toolkits. Although beautifully designed and powerful, user-friendly bioinformatics packages can be expensive and, as more arrive on the market each year, it can be difficult for researchers, teachers and students to choose the right software for their needs, especially if they do not have a bioinformatics background. This review highlights some of the currently available and most popular commercial bioinformatics packages, discussing their prices, usability, features and suitability for teaching. Although several commercial bioinformatics programs are arguably overpriced and overhyped, many are well designed, sophisticated and, in my opinion, worth the investment. If you are just beginning your foray into molecular sequence analysis or an experienced genomicist, I encourage you to explore proprietary software bundles. They have the potential to streamline your research, increase your productivity, energize your classroom and, if anything, add a bit of zest to the often dry detached world of bioinformatics. © The Author 2014. Published by Oxford University Press.

  12. Commercial Skills Test Information Management System (CSTIMS) final report and self-sustainability plan.

    DOT National Transportation Integrated Search

    2014-03-01

    The Commercial Skills Test Information Management System (CSTIMS) was developed as a Web-based, software-as-a-service system to prevent and deter fraud perpetrated by third-party commercial drivers license (CDL) examiners in the portion of the CDL...

  13. Ry Horsey | NREL

    Science.gov Websites

    Ry Horsey Photo of Henry Horsey Ry Horsey Software Developer - Commercial Buildings Energy Modeling the field of commercial building energy modeling. He is particularly interested in the increasing tools to support large-scale commercial building energy modeling. This work has led to contributions to

  14. Design Your Own Instructional Software: It's Easy.

    ERIC Educational Resources Information Center

    Pauline, Ronald F.

    Computer Assisted Instruction (CAI) is, quite simply, an instance in which instructional content activities are delivered via a computer. Many commercially-available software programs, although excellent programs, may not be acceptable for each individual teacher's classroom. One way to insure that software is not only acceptable but also targets…

  15. At the Creation: Chaos, Control, and Automation--Commercial Software Development for Archives.

    ERIC Educational Resources Information Center

    Drr, W. Theodore

    1988-01-01

    An approach to the design of flexible text-based management systems for archives includes tiers for repository, software, and user management systems. Each tier has four layers--objective, program, result, and interface. Traps awaiting software development companies involve the market, competition, operations, and finance. (10 references) (MES)

  16. Virus Alert: Ten Steps to Safe Computing.

    ERIC Educational Resources Information Center

    Gunter, Glenda A.

    1997-01-01

    Discusses computer viruses and explains how to detect them; discusses virus protection and the need to update antivirus software; and offers 10 safe computing tips, including scanning floppy disks and commercial software, how to safely download files from the Internet, avoiding pirated software copies, and backing up files. (LRW)

  17. Landsat 7 processing software and data dissemination policy issues

    NASA Astrophysics Data System (ADS)

    Aten, Michelle L.

    1999-12-01

    There are a number of controversial policy issues regarding the dissemination of Landsat 7 data and processing software. Public opinion in the various sectors in the industry such as commercial, government and academic have diverse views of which levels of data the United States government should produce as standard products. Some commercial interests are opposed to the government production of value-added products and would prefer that the government concentrate on the production of lower level products and perform only systematic level corrections. Alternatively, data users among government and academic institutions are interested in the government offering terrain and precision corrected products. In addition, the U.S. government has also produced a Landsat 7 processing software package that will permit end users to process their own data. Due to the Freedom of Information Act this software is readily available to the public since its development was funded by U.S. taxpayers, yet there are concerns that its dissemination will undermine the principle of the commercialization of space. Therefore, even if value added products are not offered as standard products, the availability of a no cost processing system could have similar impacts on the revenues of commercial firms. This discussion will provide an overview of the history of this controversy, reflect on the current situation regarding Landsat 7 data policy, and will concentrate on the advantages and disadvantages to both the private and public sectors. A comparison between the public good accomplished by the Landsat program is contrasted to the impact on commercial interests in an effort to encourage a better understanding among all interested parties.

  18. Speech dynamics are coded in the left motor cortex in fluent speakers but not in adults who stutter

    PubMed Central

    Hoang, T. N. Linh; Neef, Andreas; Paulus, Walter; Sommer, Martin

    2015-01-01

    The precise excitability regulation of neuronal circuits in the primary motor cortex is central to the successful and fluent production of speech. Our question was whether the involuntary execution of undesirable movements, e.g. stuttering, is linked to an insufficient excitability tuning of neural populations in the orofacial region of the primary motor cortex. We determined the speech-related time course of excitability modulation in the left and right primary motor tongue representation. Thirteen fluent speakers (four females, nine males; aged 23–44) and 13 adults who stutter (four females, nine males, aged 21–55) were asked to build verbs with the verbal prefix ‘auf’. Single-pulse transcranial magnetic stimulation was applied over the primary motor cortex during the transition phase between a fixed labiodental articulatory configuration and immediately following articulatory configurations, at different latencies after transition onset. Bilateral electromyography was recorded from self-adhesive electrodes placed on the surface of the tongue. Off-line, we extracted the motor evoked potential amplitudes and normalized these amplitudes to the individual baseline excitability during the fixed configuration. Fluent speakers demonstrated a prominent left hemisphere increase of motor cortex excitability in the transition phase (P = 0.009). In contrast, the excitability of the right primary motor tongue representation was unchanged. Interestingly, adults afflicted with stuttering revealed a lack of left-hemisphere facilitation. Moreover, the magnitude of facilitation was negatively correlated with stuttering frequency. Although orofacial midline muscles are bilaterally innervated from corticobulbar projections of both hemispheres, our results indicate that speech motor plans are controlled primarily in the left primary speech motor cortex. This speech motor planning-related asymmetry towards the left orofacial motor cortex is missing in stuttering. Moreover, a negative correlation between the amount of facilitation and stuttering severity suggests that we discovered a main physiological principle of fluent speech production and its role in stuttering. PMID:25595146

  19. a Comparative Analysis of Fluent and Cerebral Palsied Speech.

    NASA Astrophysics Data System (ADS)

    van Doorn, Janis Lee

    Several features of the acoustic waveforms of fluent and cerebral palsied speech were compared, using six fluent and seven cerebral palsied subjects, with a major emphasis being placed on an investigation of the trajectories of the first three formants (vocal tract resonances). To provide an overall picture which included other acoustic features, fundamental frequency, intensity, speech timing (speech rate and syllable duration), and prevocalization (vocalization prior to initial stop consonants found in cerebral palsied speech) were also investigated. Measurements were made using repetitions of a test sentence which was chosen because it required large excursions of the speech articulators (lips, tongue and jaw), so that differences in the formant trajectories for the fluent and cerebral palsied speakers would be emphasized. The acoustic features were all extracted from the digitized speech waveform (10 kHz sampling rate): the fundamental frequency contours were derived manually, the intensity contours were measured using the signal covariance, speech rate and syllable durations were measured manually, as were the prevocalization durations, while the formant trajectories were derived from short time spectra which were calculated for each 10 ms of speech using linear prediction analysis. Differences which were found in the acoustic features can be summarized as follows. For cerebral palsied speakers, the fundamental frequency contours generally showed inappropriate exaggerated fluctuations, as did some of the intensity contours; the mean fundamental frequencies were either higher or the same as for the fluent subjects; speech rates were reduced, and syllable durations were longer; prevocalization was consistently present at the beginning of the test sentence; formant trajectories were found to have overall reduced frequency ranges, and to contain anomalous transitional features, but it is noteworthy that for any one cerebral palsied subject, the inappropriate trajectory pattern was generally reproducible. The anomalous transitional features took the form of (a) inappropriate transition patterns, (b) reduced frequency excursions, (c) increased transition durations, and (d) decreased maximum rates of frequency change.

  20. Simulation of Flow around Isolated Helicopter Fuselage

    NASA Astrophysics Data System (ADS)

    Kusyumov, A. N.; Mikhailov, S. A.; Romanova, E. V.; Garipov, A. O.; Nikolaev, E. I.; Barakos, G.

    2013-04-01

    Low fuselage drag has always been a key target of helicopter manufacturers. Therefore, this paper focuses on CFD predictions of the drag of several components of a typical helicopter fuselage. In the first section of the paper, validation of the obtained CFD predictions is carried out using wind tunnel measurements. The measurements were carried out at the Kazan National Research Technical University n.a. A. Tupolev. The second section of the paper is devoted to the analysis of drag contributions of several components of the ANSAT helicopter prototype fuselage using the RANS approach. For this purpose, several configurations of fuselages are considered with different levels of complexity including exhausts and skids. Depending on the complexity of the considered configuration and CFD mesh both the multi-block structured HMB solver and the unstructured commercial tool Fluent are used. Finally, the effect of an actuator disk on the predicted drag is addressed.

  1. Heat transfer simulation in a vertical Bridgman CdTe growth configuration

    NASA Astrophysics Data System (ADS)

    Martinez-Tomas, C.; Muñoz, V.; Triboulet, R.

    1999-02-01

    Modelling and numerical simulation of crystal growth processes have been shown to be powerful tools in order to understand the physical effects of different parameters on the growth conditions. In this study a finite difference/control volume technique for the study of heat transfer has been employed. This model takes into account the whole system: furnace temperature profile, air gap between furnace walls and ampoule, ampoule geometry, crucible coating if any, solid and liquid CdTe thermal properties, conduction, convection and radiation of heat and phase change. We have used the commercial code FLUENT for the numerical resolution that can be running on a personal computer. Results show that the temperature field is very sensitive to the charge and ampoule peculiarities. As a consequence, significant differences between the velocity of the ampoule and that of the isotherm determining the solid/liquid interface have been found at the onset of the growth.

  2. Finite Element Modeling and Analysis of Powder Stream in Low Pressure Cold Spray Process

    NASA Astrophysics Data System (ADS)

    Goyal, Tarun; Walia, Ravinderjit Singh; Sharma, Prince; Sidhu, Tejinder Singh

    2016-07-01

    Low pressure cold gas dynamic spray (LPCGDS) is a coating process that utilize low pressure gas (5-10 bars instead of 25-30 bars) and the radial injection of powder instead of axial injection with the particle range (1-50 μm). In the LPCGDS process, pressurized compressed gas is accelerated to the critical velocity, which depends on length of the divergent section of nozzle, the propellant gas and particle characteristics, and the diameters ratio of the inlet and outer diameters. This paper presents finite element modeling (FEM) of powder stream in supersonic nozzle wherein adiabatic gas flow and expansion of gas occurs in uniform manner and the same is used to evaluate the resultant temperature and velocity contours during coating process. FEM analyses were performed using commercial finite volume package, ANSYS CFD FLUENT. The results are helpful to predict the characteristics of powder stream at the exit of the supersonic nozzle.

  3. A comparison of cylindrical and row trenched cooling holes with alignment angle of 0 degree near the combustor endwall

    NASA Astrophysics Data System (ADS)

    Kianpour, E.; Nor Azwadi, C. S.; Golshokouh, I.

    2013-12-01

    We studied the effects of cylindrical and row trenched cooling holes with alignment angle of 0° at BR=3.18 on the film cooling performance near the endwall surface of a combustor simulator. In this research, a three-dimensional presentation of gas turbine engine was simulated and analyzed with a commercial finite volume package FLUENT 6.2.26 to gain fundamental data. The current study has been performed with Reynolds-averaged Navier-Stokes turbulence model (RANS) on internal cooling passages. This combustor simulator combined the interaction of two rows of dilution jets, which were staggered in the stream wise direction and aligned in the span wise direction. The entire findings of the study declared that with using the row trenched holes near the enwall surface; film cooling effectiveness is doubled compared to the cooling performance of baseline case.

  4. Frost Growth CFD Model of an Integrated Active Desiccant Rooftop Unit

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Geoghegan, Patrick J; Petrov, Andrei Y; Vineyard, Edward Allan

    2008-01-01

    A frost growth model is incorporated into a Computational Fluid Dynamics (CFD) simulation of a heat pump by means of a user-defined function in FLUENT, a commercial CFD code. The transient model is applied to the outdoor section of an Integrated Active Desiccant Rooftop (IADR) unit in heating mode. IADR is a hybrid vapor compression and active desiccant unit capable of handling 100% outdoor air (dedicated outdoor air system) or as a total conditioning system, handling both outdoor air and space cooling or heating loads. The predicted increase in flow resistance and loss in heat transfer capacity due to frostmore » build-up are compared to experimental pressure drop readings and thermal imaging. The purpose of this work is to develop a CFD model that is capable of predicting frost growth, an invaluable tool in evaluating the effectiveness of defrost-on-demand cycles.« less

  5. Multiphysics Simulation of Welding-Arc and Nozzle-Arc System: Mathematical-Model, Solution-Methodology and Validation

    NASA Astrophysics Data System (ADS)

    Pawar, Sumedh; Sharma, Atul

    2018-01-01

    This work presents mathematical model and solution methodology for a multiphysics engineering problem on arc formation during welding and inside a nozzle. A general-purpose commercial CFD solver ANSYS FLUENT 13.0.0 is used in this work. Arc formation involves strongly coupled gas dynamics and electro-dynamics, simulated by solution of coupled Navier-Stoke equations, Maxwell's equations and radiation heat-transfer equation. Validation of the present numerical methodology is demonstrated with an excellent agreement with the published results. The developed mathematical model and the user defined functions (UDFs) are independent of the geometry and are applicable to any system that involves arc-formation, in 2D axisymmetric coordinates system. The high-pressure flow of SF6 gas in the nozzle-arc system resembles arc chamber of SF6 gas circuit breaker; thus, this methodology can be extended to simulate arcing phenomenon during current interruption.

  6. Effect of Blockage and Location on Mixing of Swirling Coaxial Jets in a Non-expanding Circular Confinement

    NASA Astrophysics Data System (ADS)

    Patel, V. K.; Singh, S. N.; Seshadri, V.

    2013-06-01

    A study is conducted to evolve an effective design concept to improve mixing in a combustor chamber to reduce the amount of intake air. The geometry used is that of a gas turbine combustor model. For simplicity, both the jets have been considered as air jets and effect of heat release and chemical reaction has not been modeled. Various contraction shapes and blockage have been investigated by placing them downstream at different locations with respect to inlet to obtain better mixing. A commercial CFD code `Fluent 6.3' which is based on finite volume method has been used to solve the flow in the combustor model. Validation is done with the experimental data available in literature using standard k-ω turbulence model. The study has shown that contraction and blockage at optimum location enhances the mixing process. Further, the effect of swirl in the jets has also investigated.

  7. Turbulent flow computation in a circular U-Bend

    NASA Astrophysics Data System (ADS)

    Miloud, Abdelkrim; Aounallah, Mohammed; Belkadi, Mustapha; Adjlout, Lahouari; Imine, Omar; Imine, Bachir

    2014-03-01

    Turbulent flows through a circular 180° curved bend with a curvature ratio of 3.375, defined as the the bend mean radius to pipe diameter is investigated numerically for a Reynolds number of 4.45×104. The computation is performed for a U-Bend with full long pipes at the entrance and at the exit. The commercial ANSYS FLUENT is used to solve the steady Reynolds-Averaged Navier-Stokes (RANS) equations. The performances of standard k-ɛ and the second moment closure RSM models are evaluated by comparing their numerical results against experimental data and testing their capabilities to capture the formation and extend this turbulence driven vortex. It is found that the secondary flows occur in the cross-stream half-plane of such configurations and primarily induced by high anisotropy of the cross-stream turbulent normal stresses near the outer bend.

  8. Paradigm of Legal Protection of Computer Software Contracts in the United States: Brief Overview of “Principles of the Law of Software Contracts”

    NASA Astrophysics Data System (ADS)

    Furuya, Haruhisa; Hiratsuka, Mitsuyoshi

    This article overviews the historical transition of legal protection of Computer software contracts in the Unite States and presents how it should function under Uniform Commercial Code and its amended Article 2B, Uniform Computer Information Transactions Act, and also recently-approved “Principles of the Law of Software Contracts”.

  9. NDE Software Developed at NASA Glenn Research Center

    NASA Technical Reports Server (NTRS)

    Roth, Donald J.; Martin, Richard E.; Rauser, Richard W.; Nichols, Charles; Bonacuse, Peter J.

    2014-01-01

    NASA Glenn Research Center has developed several important Nondestructive Evaluation (NDE) related software packages for different projects in the last 10 years. Three of the software packages have been created with commercial-grade user interfaces and are available to United States entities for download on the NASA Technology Transfer and Partnership Office server (https://sr.grc.nasa.gov/). This article provides brief overviews of the software packages.

  10. A Study of Covert Communications in Space Platforms Hosting Government Payloads

    DTIC Science & Technology

    2015-02-01

    possible adversarial actions (e.g., malicious software co- resident on the commercial host). Threats to the commercial supply chain are just one... supply chain to either create or exploit channel vulnerabilities. For government hosted payload missions, the critical payload data are encrypted...access to space by hosting government- supplied payloads on commercial space platforms. These commercially hosted payloads require stringent

  11. Software resilience and the effectiveness of software mitigation in microcontrollers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Quinn, Heather; Baker, Zachary; Fairbanks, Tom

    Commercially available microprocessors could be useful to the space community for noncritical computations. There are many possible components that are smaller, lower-power, and less expensive than traditional radiation-hardened microprocessors. Many commercial microprocessors have issues with single-event effects (SEEs), such as single-event upsets (SEUs) and single-event transients (SETs), that can cause the microprocessor to calculate an incorrect result or crash. In this paper we present the Trikaya technique for masking SEUs and SETs through software mitigation techniques. Furthermore, test results show that this technique can be very effective at masking errors, making it possible to fly these microprocessors for a varietymore » of missions.« less

  12. Software resilience and the effectiveness of software mitigation in microcontrollers

    DOE PAGES

    Quinn, Heather; Baker, Zachary; Fairbanks, Tom; ...

    2015-12-01

    Commercially available microprocessors could be useful to the space community for noncritical computations. There are many possible components that are smaller, lower-power, and less expensive than traditional radiation-hardened microprocessors. Many commercial microprocessors have issues with single-event effects (SEEs), such as single-event upsets (SEUs) and single-event transients (SETs), that can cause the microprocessor to calculate an incorrect result or crash. In this paper we present the Trikaya technique for masking SEUs and SETs through software mitigation techniques. Furthermore, test results show that this technique can be very effective at masking errors, making it possible to fly these microprocessors for a varietymore » of missions.« less

  13. Open source software to control Bioflo bioreactors.

    PubMed

    Burdge, David A; Libourel, Igor G L

    2014-01-01

    Bioreactors are designed to support highly controlled environments for growth of tissues, cell cultures or microbial cultures. A variety of bioreactors are commercially available, often including sophisticated software to enhance the functionality of the bioreactor. However, experiments that the bioreactor hardware can support, but that were not envisioned during the software design cannot be performed without developing custom software. In addition, support for third party or custom designed auxiliary hardware is often sparse or absent. This work presents flexible open source freeware for the control of bioreactors of the Bioflo product family. The functionality of the software includes setpoint control, data logging, and protocol execution. Auxiliary hardware can be easily integrated and controlled through an integrated plugin interface without altering existing software. Simple experimental protocols can be entered as a CSV scripting file, and a Python-based protocol execution model is included for more demanding conditional experimental control. The software was designed to be a more flexible and free open source alternative to the commercially available solution. The source code and various auxiliary hardware plugins are publicly available for download from https://github.com/LibourelLab/BiofloSoftware. In addition to the source code, the software was compiled and packaged as a self-installing file for 32 and 64 bit windows operating systems. The compiled software will be able to control a Bioflo system, and will not require the installation of LabVIEW.

  14. Open Source Software to Control Bioflo Bioreactors

    PubMed Central

    Burdge, David A.; Libourel, Igor G. L.

    2014-01-01

    Bioreactors are designed to support highly controlled environments for growth of tissues, cell cultures or microbial cultures. A variety of bioreactors are commercially available, often including sophisticated software to enhance the functionality of the bioreactor. However, experiments that the bioreactor hardware can support, but that were not envisioned during the software design cannot be performed without developing custom software. In addition, support for third party or custom designed auxiliary hardware is often sparse or absent. This work presents flexible open source freeware for the control of bioreactors of the Bioflo product family. The functionality of the software includes setpoint control, data logging, and protocol execution. Auxiliary hardware can be easily integrated and controlled through an integrated plugin interface without altering existing software. Simple experimental protocols can be entered as a CSV scripting file, and a Python-based protocol execution model is included for more demanding conditional experimental control. The software was designed to be a more flexible and free open source alternative to the commercially available solution. The source code and various auxiliary hardware plugins are publicly available for download from https://github.com/LibourelLab/BiofloSoftware. In addition to the source code, the software was compiled and packaged as a self-installing file for 32 and 64 bit windows operating systems. The compiled software will be able to control a Bioflo system, and will not require the installation of LabVIEW. PMID:24667828

  15. Ideas in Practice (3): A Simulated Laboratory Experience in Digital Design.

    ERIC Educational Resources Information Center

    Cleaver, Thomas G.

    1988-01-01

    Gives an example of the use of a simplified logic simulator in a logic design course. Discusses some problems in logic design classes, commercially available software, and software problems. Describes computer-aided engineering (CAE) software. Lists 14 experiments in the simulated laboratory and presents students' evaluation of the course. (YP)

  16. 32 CFR 37.550 - May I accept intellectual property as cost sharing?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... software) as cost sharing, because: (1) It is difficult to assign values to these intangible contributions... offer the use of commercially available software for which there is an established license fee for use of the product. The costs of the development of the software would not be a reasonable basis for...

  17. 32 CFR 37.550 - May I accept intellectual property as cost sharing?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... offer the use of commercially available software for which there is an established license fee for use of the product. The costs of the development of the software would not be a reasonable basis for... software) as cost sharing, because: (1) It is difficult to assign values to these intangible contributions...

  18. A Guide to Street Tree Inventory Software

    Treesearch

    Gene A. Olig; Robert W. Miller

    1997-01-01

    The purpose of this publication is to serve as a reference and guide for urban forestry professionals in the selection of a street tree inventory software program. The programs described include only those that are commercially available. The increasing demand for street tree inventory software follows a trend towards a more computerized society and the increasing...

  19. ELAS: A powerful, general purpose image processing package

    NASA Technical Reports Server (NTRS)

    Walters, David; Rickman, Douglas

    1991-01-01

    ELAS is a software package which has been utilized as an image processing tool for more than a decade. It has been the source of several commercial packages. Now available on UNIX workstations it is a very powerful, flexible set of software. Applications at Stennis Space Center have included a very wide range of areas including medicine, forestry, geology, ecological modeling, and sonar imagery. It remains one of the most powerful image processing packages available, either commercially or in the public domain.

  20. DISRUPTION OF LARGE-SCALE NEURAL NETWORKS IN NON-FLUENT/AGRAMMATIC VARIANT PRIMARY PROGRESSIVE APHASIA ASSOCIATED WITH FRONTOTEMPORAL DEGENERATION PATHOLOGY

    PubMed Central

    Grossman, Murray; Powers, John; Ash, Sherry; McMillan, Corey; Burkholder, Lisa; Irwin, David; Trojanowski, John Q.

    2012-01-01

    Non-fluent/agrammatic primary progressive aphasia (naPPA) is a progressive neurodegenerative condition most prominently associated with slowed, effortful speech. A clinical imaging marker of naPPA is disease centered in the left inferior frontal lobe. We used multimodal imaging to assess large-scale neural networks underlying effortful expression in 15 patients with sporadic naPPA due to frontotemporal lobar degeneration (FTLD) spectrum pathology. Effortful speech in these patients is related in part to impaired grammatical processing, and to phonologic speech errors. Gray matter (GM) imaging shows frontal and anterior-superior temporal atrophy, most prominently in the left hemisphere. Diffusion tensor imaging reveals reduced fractional anisotropy in several white matter (WM) tracts mediating projections between left frontal and other GM regions. Regression analyses suggest disruption of three large-scale GM-WM neural networks in naPPA that support fluent, grammatical expression. These findings emphasize the role of large-scale neural networks in language, and demonstrate associated language deficits in naPPA. PMID:23218686

  1. What's in a sentence? The crucial role of lexical content in sentence production in nonfluent aphasia.

    PubMed

    Speer, Paula; Wilshire, Carolyn E

    2013-01-01

    This study investigated the effect of lexical content on sentence production in nonfluent aphasia. Five participants with nonfluent aphasia, four with fluent aphasia, and eight controls were asked to describe pictured events in subject-verb-object sentences. Experiment 1 manipulated speed of lexical retrieval by varying the frequency of sentence nouns. Nonfluent participants' accuracy was consistently higher for sentences commencing with a high- than with a low-frequency subject noun, even when errors on those nouns were themselves excluded. This was not the case for the fluent participants. Experiment 2 manipulated the semantic relationship between subject and object nouns. The nonfluent participants produced sentences less accurately when they contained related than when they contained unrelated lexical items. The fluent participants exhibited the opposite trend. We propose that individuals with nonfluent aphasia are disproportionately reliant on activated conceptual-lexical representations to drive the sentence generation process, an idea we call the content drives structure (COST) hypothesis.

  2. Unbiased and unnoticed verbal conditioning: the double agent robot procedure1

    PubMed Central

    Rosenfeld, Howard M.; Baer, Donald M.

    1970-01-01

    Subjects who were told they were “experimenters” attempted to reinforce fluent speech in a supposed subject with whom they spoke via intercom. The supposed subject was to say nouns, one at a time, on request by the “experimenter”, who reinforced fluent pronunciation with points. Actually, the “experimenter” was talking to a multi-track tape recording, one track of which contained fluently spoken nouns, the other track containing disfluently spoken nouns. If the “experimenter's” request for the next noun was in a specified form a word from the fluent track was played to him as reinforcement; requests in any other form produced the word from the disfluent track. Repeated conditioning of specific forms of requests was accomplished with two subject-“experimenters,” who were unable to describe changes in their own behavior, or the contingencies applied. This technique improved upon an earlier method that had yielded similar results, but was less thoroughly controlled against possible human bias. PMID:16811461

  3. Instrument Package Manipulation Through the Generation and Use of an Attenuated-Fluent Gas Fold

    NASA Technical Reports Server (NTRS)

    Breen, Daniel P.

    2012-01-01

    This document discusses a technique that provides a means for suspending large, awkward loads, instrument packages, components, and machinery in a stable, controlled, and precise manner. In the baseplate of the test machine, a pattern of grooves and ports is installed that when pressurized generates an attenuated- fluent gas fold providing a low-cost, near-zero-coefficient-of-friction lubrication boundary layer that supports the object evenly, and in a predictable manner. Package movement control requires minimal force. Aids to repeatable travel and positional accuracy can be added via the addition of simple guide bars and stops to the floor or object being moved. This allows easily regulated three-axis motions. Loads of extreme weight and size can be moved and guided by a single person, or by automated means, using minimal force. Upon removal of the attenuated fluent gas fold, the object returns to a stable resting position without impact forces affecting the object.

  4. Experience with case tools in the design of process-oriented software

    NASA Astrophysics Data System (ADS)

    Novakov, Ognian; Sicard, Claude-Henri

    1994-12-01

    In Accelerator systems such as the CERN PS complex, process equipment has a life time which may exceed the typical life cycle of its related software. Taking into account the variety of such equipment, it is important to keep the analysis and design of the software in a system-independent form. This paper discusses the experience gathered in using commercial CASE tools for analysis, design and reverse engineering of different process-oriented software modules, with a principal emphasis on maintaining the initial analysis in a standardized form. Such tools have been in existence for several years, but this paper shows that they are not fully adapted to our needs. In particular, the paper stresses the problems of integrating such a tool into an existing data-base-dependent development chain, the lack of real-time simulation tools and of Object-Oriented concepts in existing commercial packages. Finally, the paper gives a broader view of software engineering needs in our particular context.

  5. Virtual rough samples to test 3D nanometer-scale scanning electron microscopy stereo photogrammetry.

    PubMed

    Villarrubia, J S; Tondare, V N; Vladár, A E

    2016-01-01

    The combination of scanning electron microscopy for high spatial resolution, images from multiple angles to provide 3D information, and commercially available stereo photogrammetry software for 3D reconstruction offers promise for nanometer-scale dimensional metrology in 3D. A method is described to test 3D photogrammetry software by the use of virtual samples-mathematical samples from which simulated images are made for use as inputs to the software under test. The virtual sample is constructed by wrapping a rough skin with any desired power spectral density around a smooth near-trapezoidal line with rounded top corners. Reconstruction is performed with images simulated from different angular viewpoints. The software's reconstructed 3D model is then compared to the known geometry of the virtual sample. Three commercial photogrammetry software packages were tested. Two of them produced results for line height and width that were within close to 1 nm of the correct values. All of the packages exhibited some difficulty in reconstructing details of the surface roughness.

  6. A Simplified Mesh Deformation Method Using Commercial Structural Analysis Software

    NASA Technical Reports Server (NTRS)

    Hsu, Su-Yuen; Chang, Chau-Lyan; Samareh, Jamshid

    2004-01-01

    Mesh deformation in response to redefined or moving aerodynamic surface geometries is a frequently encountered task in many applications. Most existing methods are either mathematically too complex or computationally too expensive for usage in practical design and optimization. We propose a simplified mesh deformation method based on linear elastic finite element analyses that can be easily implemented by using commercially available structural analysis software. Using a prescribed displacement at the mesh boundaries, a simple structural analysis is constructed based on a spatially varying Young s modulus to move the entire mesh in accordance with the surface geometry redefinitions. A variety of surface movements, such as translation, rotation, or incremental surface reshaping that often takes place in an optimization procedure, may be handled by the present method. We describe the numerical formulation and implementation using the NASTRAN software in this paper. The use of commercial software bypasses tedious reimplementation and takes advantage of the computational efficiency offered by the vendor. A two-dimensional airfoil mesh and a three-dimensional aircraft mesh were used as test cases to demonstrate the effectiveness of the proposed method. Euler and Navier-Stokes calculations were performed for the deformed two-dimensional meshes.

  7. System integration test plan for HANDI 2000 business management system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wilson, D.

    This document presents the system integration test plan for the Commercial-Off-The-Shelf, PassPort and PeopleSoft software, and custom software created to work with the COTS products. The PP software is an integrated application for AP, Contract Management, Inventory Management, Purchasing and Material Safety Data Sheet. The PS software is an integrated application for Project Costing, General Ledger, Human Resources/Training, Payroll, and Base Benefits.

  8. Rapid Building Assessment Project

    DTIC Science & Technology

    2014-05-01

    ongoing management of commercial energy efficiency. No other company offers all of these proven services on a seamless, integrated Software -as-a- Service ...FirstFuel has added a suite of additional Software -as-a- Service analytics capabilities to support the entire energy efficiency lifecycle, including...the client side. In this document, we refer to the service side software as “BUILDER” and the client software as “BuilderRED,” following the Army

  9. The Advanced Human Eye Model (AHEM): a personal binocular eye modeling system inclusive of refraction, diffraction, and scatter.

    PubMed

    Donnelly, William

    2008-11-01

    To present a commercially available software tool for creating eye models to assist the development of ophthalmic optics and instrumentation, simulate ailments or surgery-induced changes, explore vision research questions, and provide assistance to clinicians in planning treatment or analyzing clinical outcomes. A commercially available eye modeling system was developed, the Advanced Human Eye Model (AHEM). Two mainstream optical software engines, ZEMAX (ZEMAX Development Corp) and ASAP (Breault Research Organization), were used to construct a similar software eye model and compared. The method of using the AHEM is described and various eye modeling scenarios are created. These scenarios consist of retinal imaging of targets and sources; optimization capability; spectacles, contact lens, and intraocular lens insertion and correction; Zernike surface deformation on the cornea; cataract simulation and scattering; a gradient index lens; a binocular mode; a retinal implant; system import/export; and ray path exploration. Similarity of the two different optical software engines showed validity to the mechanism of the AHEM. Metrics and graphical data are generated from the various modeling scenarios particular to their input specifications. The AHEM is a user-friendly commercially available software tool from Breault Research Organization, which can assist the design of ophthalmic optics and instrumentation, simulate ailments or refractive surgery-induced changes, answer vision research questions, or assist clinicians in planning treatment or analyzing clinical outcomes.

  10. Graphic representations: keys to disclose the codex of nature

    NASA Astrophysics Data System (ADS)

    Caramelo, Liliana; Gonçalves, Norberto; Pereira, Mário; Soares, Armando; Naia, Marco

    2010-05-01

    Undergraduate and university level students present some difficulties to understand and interpret many of the geosciences concepts, in particular those represented by vector and scalar fields. Our experience reveals that these difficulties are associated with a lack in the development of their abstraction and mental picturing abilities. On the other hand, these students have easy access to communication and information technology software which can be used to built graphic representations of experimental data, time series and vector and scalar fields. This transformation allows an easiest extraction, interpretation and summary of the most important characteristics in the data. There is already commercial and open source software with graphical tools that can be used for this purpose but commercial software packs with user friendly interfaces but their price is not negligible. Open source software can circumvent this difficulty even if, in general, their graphical user interface hasn't reached the desirable level of the commercial ones. We will show a simple procedure to generate an image from the data that characterizes the generation of the suitable images illustrating the key concepts in study, using a freeware code, exactly as it is presented to the students in our open teaching sessions to the general student community. Our experience demonstrated that the students are very enthusiastic using this approach. Furthermore, the use of this software can easily be adopted by teachers and students of secondary schools as part of curricular activities.

  11. Temperature Distribution Within a Defect-Free Silicon Carbide Diode Predicted by a Computational Model

    NASA Technical Reports Server (NTRS)

    Kuczmarski, Maria A.; Neudeck, Philip G.

    2000-01-01

    Most solid-state electronic devices diodes, transistors, and integrated circuits are based on silicon. Although this material works well for many applications, its properties limit its ability to function under extreme high-temperature or high-power operating conditions. Silicon carbide (SiC), with its desirable physical properties, could someday replace silicon for these types of applications. A major roadblock to realizing this potential is the quality of SiC material that can currently be produced. Semiconductors require very uniform, high-quality material, and commercially available SiC tends to suffer from defects in the crystalline structure that have largely been eliminated in silicon. In some power circuits, these defects can focus energy into an extremely small area, leading to overheating that can damage the device. In an effort to better understand the way that these defects affect the electrical performance and reliability of an SiC device in a power circuit, the NASA Glenn Research Center at Lewis Field began an in-house three-dimensional computational modeling effort. The goal is to predict the temperature distributions within a SiC diode structure subjected to the various transient overvoltage breakdown stresses that occur in power management circuits. A commercial computational fluid dynamics computer program (FLUENT-Fluent, Inc., Lebanon, New Hampshire) was used to build a model of a defect-free SiC diode and generate a computational mesh. A typical breakdown power density was applied over 0.5 msec in a heated layer at the junction between the p-type SiC and n-type SiC, and the temperature distribution throughout the diode was then calculated. The peak temperature extracted from the computational model agreed well (within 6 percent) with previous first-order calculations of the maximum expected temperature at the end of the breakdown pulse. This level of agreement is excellent for a model of this type and indicates that three-dimensional computational modeling can provide useful predictions for this class of problem. The model is now being extended to include the effects of crystal defects. The model will provide unique insights into how high the temperature rises in the vicinity of the defects in a diode at various power densities and pulse durations. This information also will help researchers in understanding and designing SiC devices for safe and reliable operation in high-power circuits.

  12. NREL Announces Third Round of Start-Ups to Participate in the Wells Fargo

    Science.gov Websites

    innovative commercial building technologies Photo of NREL researchers talking. George Lee and Steven Low that provide scalable solutions to reduce the energy impact of commercial buildings. Including Round 3 kit for commercial buildings. Referred to apply to program by University of Colorado Boulder Software

  13. 48 CFR 208.7403 - Acquisition procedures.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SYSTEM, DEPARTMENT OF DEFENSE ACQUISITION PLANNING REQUIRED SOURCES OF SUPPLIES AND SERVICES Enterprise Software Agreements 208.7403 Acquisition procedures. Follow the procedures at PGI 208.7403 when acquiring commercial software and related services. [71 FR 39005, July 11, 2006] ...

  14. Look What Microcomputers Are Up to Now!

    ERIC Educational Resources Information Center

    Wilkins, Mary E.

    1989-01-01

    A teacher of hearing-impaired students describes commercially available software for teaching sign language and finger spelling, lists sources of information about other software programs, and offers suggestions to encourage teachers to utilize computers in their classrooms. (JDD)

  15. Summary of Research Report Cooperative Agreement

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Several areas of work related to commercialization of technology developed at NASA Ames Research Center (ARC) are discussed in this report. The areas are: (1) perform a feasibility study to develop a software commercialization center is at ARC; (2) perform preliminary work for formation of joint development of sensor technology for telemedicine applications; (3) development of a discovery interview process and staff training to assist the commercialization of technology developed at Ames, specifically aimed at working with researchers; (4) develop partners to further develop and commercialize image compression technology developed at AMES; (5) assist efforts to commercialize a software technology which imparts the ability to establish relevance-based retrieval in the handling of large repositories of information; (6) explore the development of cryocooler technology using pulse tube refrigeration; (7) assess interest in commercialization of a new method of measuring skin friction drag on wind tunnel models using liquid crystal material; (8) attempt to incorporate emerging technologies in the infrastructure of natural hazards mitigation; and (9) forming a nonprofit organization, "The Bootstrap Alliance", whose mission is to promote the use of digital technologies for collaborative problem solving. The results of these initiatives are discussed.

  16. Network Profiling Using Flow

    DTIC Science & Technology

    2012-08-01

    Software Engineering Institute, a federally funded research and development center. Any opinions, findings and conclusions or recommendations...CARNEGIE MELLON UNIVERSITY AND SOFTWARE ENGINEERING INSTITUTE MATERIAL IS FURNISHED ON AN “AS-IS” BASIS. CARNEGIE MELLON UNIVERSITY MAKES NO WARRANTIES OF...required for any other external and/or commercial use. Requests for permission should be directed to the Software Engineering Institute at permission

  17. EMTA-NLA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    2009-10-14

    EMTA-NLA is a computer program for analyzing the nonlinear stiffness, strength, and thermo-elastic properties of discontinuous fiber composite materials. Discontinuous fiber composites are chopped-fiber reinforced polymer materials that are formed by injection molding or compression molding techniques. The fibers tend to align during forming as the composite flows and fills the mold. EMTA-NLA can read the fiber orientation data from the molding software, Autodesk Moldflow Plastics Insight, and calculate the local material properties for accurately analyzing the warpage, stiffness, and strength of the as-formed composite part using the commercial NLA software. Therefore, EMTA-NLA is a unique assembly of mathematical algorithmsmore » that provide a one-of-a-kind composites constitutive model that links these two powerful commercial software packages.« less

  18. Integrated Robot Task and Motion Planning in the Now

    DTIC Science & Technology

    2012-06-29

    so that it can effectively achieve its goals? 1 Figure 1: Simulated apartment environment with pans, cups, sink, stove, and furniture . We propose a...s. We also use s[o].min and s[o]. max to name the left and right edges of the object (loc is the same as min). 2.3 Fluents A fluent is a condition...s) := (r.min ≤ s[o].min + δ) & (r.max ≥ s[o]. max − δ) . • ClearX (r, x): region r is clear, except for exceptions, x, which is a set of objects

  19. Optical Coherence Tomography Angiography in Optic Disc Swelling.

    PubMed

    Fard, Masoud Aghsaei; Jalili, Jalil; Sahraiyan, Alireza; Khojasteh, Hassan; Hejazi, Marjane; Ritch, Robert; Subramanian, Prem S

    2018-05-04

    To compare optical coherence tomography angiography (OCT-A) of peripapillary total vasculature and capillaries in patients with optic disc swelling. Cross-sectional study. Twenty nine eyes with acute nonarteritic anterior ischemic optic neuropathy (NAION), 44 eyes with papilledema, 8 eyes with acute optic neuritis, and 48 eyes of normal subjects were imaged using OCT-A. Peripapillary total vasculature information was recorded using a commercial vessel density map. Customized image analysis with major vessel removal was also used to measure whole-image capillary density and peripapillary capillary density (PCD). Mixed models showed that the peripapillary total vasculature density values were significantly lower in NAION eyes, followed by papilledema eyes and control eyes, using commercial software (P < .0001 for all comparisons). The customized software also showed significantly lower PCD of NAION eyes compared with papilledema eyes (all P < .001), but did not show significant differences between papilledema and control subjects. Our software showed significantly lower whole image and PCD in eyes with optic neuritis than papilledema. There was no significant difference between NAION and optic neuritis using our software. The area under the receiver operating curves for discriminating NAION from papilledema eyes and optic neuritis from papilledema eyes was highest for whole-image capillary density (0.94 and 0.80, respectively) with our software, followed by peripapillary total vasculature (0.9 and 0.74, respectively ) with commercial software. OCT-A is helpful to distinguish NAION and papillitis from papilledema. Whole-image capillary density had the greatest diagnostic accuracy for differentiating disc swelling. Copyright © 2018 Elsevier Inc. All rights reserved.

  20. Commercialization of NESSUS: Status

    NASA Technical Reports Server (NTRS)

    Thacker, Ben H.; Millwater, Harry R.

    1991-01-01

    A plan was initiated in 1988 to commercialize the Numerical Evaluation of Stochastic Structures Under Stress (NESSUS) probabilistic structural analysis software. The goal of the on-going commercialization effort is to begin the transfer of Probabilistic Structural Analysis Method (PSAM) developed technology into industry and to develop additional funding resources in the general area of structural reliability. The commercialization effort is summarized. The SwRI NESSUS Software System is a general purpose probabilistic finite element computer program using state of the art methods for predicting stochastic structural response due to random loads, material properties, part geometry, and boundary conditions. NESSUS can be used to assess structural reliability, to compute probability of failure, to rank the input random variables by importance, and to provide a more cost effective design than traditional methods. The goal is to develop a general probabilistic structural analysis methodology to assist in the certification of critical components in the next generation Space Shuttle Main Engine.

  1. Computerizing the Accounting Curriculum.

    ERIC Educational Resources Information Center

    Nash, John F.; England, Thomas G.

    1986-01-01

    Discusses the use of computers in college accounting courses. Argues that the success of new efforts in using computers in teaching accounting is dependent upon increasing instructors' computer skills, and choosing appropriate hardware and software, including commercially available business software packages. (TW)

  2. The Apple III.

    ERIC Educational Resources Information Center

    Ditlea, Steve

    1982-01-01

    Describes and evaluates the features, performance, peripheral devices, available software, and capabilities of the Apple III microcomputer. The computer's operating system, its hardware, and the commercially produced software it accepts are discussed. Specific applications programs for financial planning, accounting, and word processing are…

  3. Study on aerodynamics characteristics an urban concept car for energy-efficient race

    NASA Astrophysics Data System (ADS)

    Ambarita, H.; Siregar, M. R.; Kawai, H.

    2018-03-01

    "Horas Mesin USU" is a prototype of urban concept vehicle designed by University of Sumatera Utara to participate in the energy-efficient competition. This paper deals with a numerical study on aerodynamic characteristics of the Horas Mesin USU. The numerical analyses are carried out by solving the governing equations using CFD FLUENT commercial code. The turbulent flow is closed using k-epsilon turbulence model. In the results, pathline, velocity vector and pressure distribution are plotted. By using the pressure distributions, drag and lift coefficients are calculated. In order to make a comparison, the aerodynamic characteristics of the present design are compared with commercial city car Ford-Fiesta. The averaged drag coefficients of Horas Mesin USU and Ford-Fiesta are 0.24320 and 0.29598, respectively. On the other hand, the averaged lift coefficients of the Horas Mesin USU and Ford-Fiesta are 0.03192202 and 0.09485621, respectively. This fact suggests that Ford-Fiesta has a better aerodynamic performance in comparison with Horas Mesin USU. The flow field analysis shows that there are many modifications can be proposed to improve the aerodynamic performance of the Horas Mesin USU. It is suggested to perform further analysis to improve the aerodynamic performance of Horas Mesin USU.

  4. Multi-institutional Validation Study of Commercially Available Deformable Image Registration Software for Thoracic Images.

    PubMed

    Kadoya, Noriyuki; Nakajima, Yujiro; Saito, Masahide; Miyabe, Yuki; Kurooka, Masahiko; Kito, Satoshi; Fujita, Yukio; Sasaki, Motoharu; Arai, Kazuhiro; Tani, Kensuke; Yagi, Masashi; Wakita, Akihisa; Tohyama, Naoki; Jingu, Keiichi

    2016-10-01

    To assess the accuracy of the commercially available deformable image registration (DIR) software for thoracic images at multiple institutions. Thoracic 4-dimensional (4D) CT images of 10 patients with esophageal or lung cancer were used. Datasets for these patients were provided by DIR-lab (dir-lab.com) and included a coordinate list of anatomic landmarks (300 bronchial bifurcations) that had been manually identified. Deformable image registration was performed between the peak-inhale and -exhale images. Deformable image registration error was determined by calculating the difference at each landmark point between the displacement calculated by DIR software and that calculated by the landmark. Eleven institutions participated in this study: 4 used RayStation (RaySearch Laboratories, Stockholm, Sweden), 5 used MIM Software (Cleveland, OH), and 3 used Velocity (Varian Medical Systems, Palo Alto, CA). The ranges of the average absolute registration errors over all cases were as follows: 0.48 to 1.51 mm (right-left), 0.53 to 2.86 mm (anterior-posterior), 0.85 to 4.46 mm (superior-inferior), and 1.26 to 6.20 mm (3-dimensional). For each DIR software package, the average 3-dimensional registration error (range) was as follows: RayStation, 3.28 mm (1.26-3.91 mm); MIM Software, 3.29 mm (2.17-3.61 mm); and Velocity, 5.01 mm (4.02-6.20 mm). These results demonstrate that there was moderate variation among institutions, although the DIR software was the same. We evaluated the commercially available DIR software using thoracic 4D-CT images from multiple centers. Our results demonstrated that DIR accuracy differed among institutions because it was dependent on both the DIR software and procedure. Our results could be helpful for establishing prospective clinical trials and for the widespread use of DIR software. In addition, for clinical care, we should try to find the optimal DIR procedure using thoracic 4D-CT data. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Multi-institutional Validation Study of Commercially Available Deformable Image Registration Software for Thoracic Images

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kadoya, Noriyuki, E-mail: kadoya.n@rad.med.tohoku.ac.jp; Nakajima, Yujiro; Saito, Masahide

    Purpose: To assess the accuracy of the commercially available deformable image registration (DIR) software for thoracic images at multiple institutions. Methods and Materials: Thoracic 4-dimensional (4D) CT images of 10 patients with esophageal or lung cancer were used. Datasets for these patients were provided by DIR-lab ( (dir-lab.com)) and included a coordinate list of anatomic landmarks (300 bronchial bifurcations) that had been manually identified. Deformable image registration was performed between the peak-inhale and -exhale images. Deformable image registration error was determined by calculating the difference at each landmark point between the displacement calculated by DIR software and that calculated bymore » the landmark. Results: Eleven institutions participated in this study: 4 used RayStation (RaySearch Laboratories, Stockholm, Sweden), 5 used MIM Software (Cleveland, OH), and 3 used Velocity (Varian Medical Systems, Palo Alto, CA). The ranges of the average absolute registration errors over all cases were as follows: 0.48 to 1.51 mm (right-left), 0.53 to 2.86 mm (anterior-posterior), 0.85 to 4.46 mm (superior-inferior), and 1.26 to 6.20 mm (3-dimensional). For each DIR software package, the average 3-dimensional registration error (range) was as follows: RayStation, 3.28 mm (1.26-3.91 mm); MIM Software, 3.29 mm (2.17-3.61 mm); and Velocity, 5.01 mm (4.02-6.20 mm). These results demonstrate that there was moderate variation among institutions, although the DIR software was the same. Conclusions: We evaluated the commercially available DIR software using thoracic 4D-CT images from multiple centers. Our results demonstrated that DIR accuracy differed among institutions because it was dependent on both the DIR software and procedure. Our results could be helpful for establishing prospective clinical trials and for the widespread use of DIR software. In addition, for clinical care, we should try to find the optimal DIR procedure using thoracic 4D-CT data.« less

  6. OSI for hardware/software interoperability

    NASA Astrophysics Data System (ADS)

    Wood, Richard J.; Harvey, Donald L.; Linderman, Richard W.; Gardener, Gary A.; Capraro, Gerard T.

    1994-03-01

    There is a need in public safety for real-time data collection and transmission from one or more sensors. The Rome Laboratory and the Ballistic Missile Defense Organization are pursuing an effort to bring the benefits of Open System Architectures (OSA) to embedded systems within the Department of Defense. When developed properly OSA provides interoperability, commonality, graceful upgradeability, survivability and hardware/software transportability to greatly minimize life cycle costs, integration and supportability. Architecture flexibility can be achieved to take advantage of commercial accomplishments by basing these developments on vendor-neutral commercially accepted standards and protocols.

  7. Scaling Retro-Commissioning to Small Commercial Buildings: A Turnkey Automated Hardware-Software Solution

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lin, Guanjing; Granderson, J.; Brambley, Michael R.

    2015-07-01

    In the United States, small commercial buildings represent 51% of total floor space of all commercial buildings and consume nearly 3 quadrillion Btu (3.2 quintillion joule) of site energy annually, presenting an enormous opportunity for energy savings. Retro-commissioning (RCx), the process through which professional energy service providers identify and correct operational problems, has proven to be a cost-effective means to achieve median energy savings of 16%. However, retro-commissioning is not typically conducted at scale throughout the commercial stock. Very few small commercial buildings are retro-commissioned because utility expenses are relatively modest, margins are tighter, and capital for improvements is limited.more » In addition, small buildings do not have in-house staff with the expertise to identify improvement opportunities. In response, a turnkey hardware-software solution was developed to enable cost-effective, monitoring-based RCx of small commercial buildings. This highly tailored solution enables non-commissioning providers to identify energy and comfort problems, as well as associated cost impacts and remedies. It also facilitates scale by offering energy service providers the means to streamline their existing processes and reduce costs by more than half. The turnkey RCx sensor suitcase consists of two primary components: a suitcase of sensors for short-term building data collection that guides users through the process of deploying and retrieving their data and a software application that automates analysis of sensor data, identifies problems and generates recommendations. This paper presents the design and testing of prototype models, including descriptions of the hardware design, analysis algorithms, performance testing, and plans for dissemination.« less

  8. Simulation Of The Synovial Fluid In A Deformable Cavity

    NASA Astrophysics Data System (ADS)

    Martinez-Gutierrez, Nancy; Ibarra-Bracamontes, Laura A.

    2016-11-01

    The main components of a synovial joint are a cartilage and a biofluid known as the synovial fluid. The results were obtained using the FLUENT software to simulate the behavior of the synovial fluid within a deformable cavity with a simple geometry. The cartilage is represented as a porous region. By reducing the available region for the fluid, a fluid displacement into the cartilage is induced. The total pressure reached in the interface of the deformable cavity and the porous region is presented. The geometry and properties of the system are scaled to values found in a knee joint. The effect of deformation rate, fluid viscosity and properties of the porous medium on the total pressure reached are analyzed. The higher pressures are reached either for high deformation rate or when the fluid viscosity increases. This study was supported by the Mexican Council of Science and Technology (CONACyT) and by the Scientific Research Coordination of the University of Michoacan in Mexico.

  9. [The numerical simulation of the internal flow field inside the pressure generator of a continuous positive airway pressure ventilator].

    PubMed

    Cheng, Yunzhang; Zhu, Lihua; Zhang, Weiguo; Wu, Wenquan

    2011-12-01

    The problem of noise in ventilator has always been an important topic to study in the development of the ventilator. A great number of data are showing that there are still large gaps of research and application levels in noise control of the ventilator between China and some more advanced foreign countries. In this study, with cooperation of the Shanghai Medical Equipment Limited Liability Company, we used the computational fluid dynamics (CFD), software FLUENT, adopted the standard k-epsilon turbulence model and the SIMPLE algorithm to simulate the inner flow field of the continuous positive airway pressure (CPAP) ventilator's pressure generator. After a detailed analysis, we figured out that there are several deficiencies in this ventilator, like local reflow in volute, uneven velocity distribution and local negative pressure in inlet of the impeller, which easily lead to noise and affect the ventilator's performances. So, it needs to be improved to a certain extent.

  10. An Intelligent Agent-Controlled and Robot-Based Disassembly Assistant

    NASA Astrophysics Data System (ADS)

    Jungbluth, Jan; Gerke, Wolfgang; Plapper, Peter

    2017-09-01

    One key for successful and fluent human-robot-collaboration in disassembly processes is equipping the robot system with higher autonomy and intelligence. In this paper, we present an informed software agent that controls the robot behavior to form an intelligent robot assistant for disassembly purposes. While the disassembly process first depends on the product structure, we inform the agent using a generic approach through product models. The product model is then transformed to a directed graph and used to build, share and define a coarse disassembly plan. To refine the workflow, we formulate “the problem of loosening a connection and the distribution of the work” as a search problem. The created detailed plan consists of a sequence of actions that are used to call, parametrize and execute robot programs for the fulfillment of the assistance. The aim of this research is to equip robot systems with knowledge and skills to allow them to be autonomous in the performance of their assistance to finally improve the ergonomics of disassembly workstations.

  11. Design of Friction Stir Welding Tool for Avoiding Root Flaws

    PubMed Central

    Ji, Shude; Xing, Jingwei; Yue, Yumei; Ma, Yinan; Zhang, Liguo; Gao, Shuangsheng

    2013-01-01

    In order to improve material flow behavior during friction stir welding and avoid root flaws of weld, a tool with a half-screw pin and a tool with a tapered-flute pin are suggested. The effect of flute geometry in tool pins on material flow velocity is investigated by the software ANSYS FLUENT. Numerical simulation results show that high material flow velocity appears near the rotational tool and material flow velocity rapidly decreases with the increase of distance away from the axis of the tool. Maximum material flow velocity by the tool with the tapered-flute pin appears at the beginning position of flute and the velocity decreases with the increase of flow length in flute. From the view of increasing the flow velocity of material near the bottom of the workpiece or in the middle of workpiece, the tool with the half-screw pin and the tool with the tapered-flute pin are both better than the conventional tool. PMID:28788426

  12. Design of Friction Stir Welding Tool for Avoiding Root Flaws.

    PubMed

    Ji, Shude; Xing, Jingwei; Yue, Yumei; Ma, Yinan; Zhang, Liguo; Gao, Shuangsheng

    2013-12-12

    In order to improve material flow behavior during friction stir welding and avoid root flaws of weld, a tool with a half-screw pin and a tool with a tapered-flute pin are suggested. The effect of flute geometry in tool pins on material flow velocity is investigated by the software ANSYS FLUENT. Numerical simulation results show that high material flow velocity appears near the rotational tool and material flow velocity rapidly decreases with the increase of distance away from the axis of the tool. Maximum material flow velocity by the tool with the tapered-flute pin appears at the beginning position of flute and the velocity decreases with the increase of flow length in flute. From the view of increasing the flow velocity of material near the bottom of the workpiece or in the middle of workpiece, the tool with the half-screw pin and the tool with the tapered-flute pin are both better than the conventional tool.

  13. The Weight Loss Effect of Heated Inner Cylinder by Free Convection in Horizontal Cylindrical Enclosure

    NASA Astrophysics Data System (ADS)

    Sboev, I. O.; Kondrashov, A. N.; Rybkin, K. A.; Burkova, L. N.; Goncharov, M. M.

    2018-03-01

    The work presents results of numerical simulations of natural convection in cavity formed by the surfaces of two horizontal coaxial cylinders. The temperature of the outer cylinder is constant. The area between the cylinders is filled with an ideal incompressible fluid. The inner cylinder is set as the heater. The solution of the equations of thermal convection in a two-dimensional approximation performed by the software package ANSYS Fluent with finite volume method. The study compares the results of numerical simulation with several well-known theoretical and experimental results. The nature of interaction of the inner cylinder with a convection current created in the gap was observed. It was shown that the flux appeared around a heated cylinder affects the weight of the heat source and causes an additional lift force from the surrounding fluid. The various Rayleigh numbers (from 1.0 ṡ 103 to 1.5 ṡ 106) and fluid with different Prandtl number (from 0.5 to 1.0 ṡ 105) are considered.

  14. Numerical Simulation of the Effects of Water Surface in Building Environment

    NASA Astrophysics Data System (ADS)

    Li, Guangyao; Pan, Yuqing; Yang, Li

    2018-03-01

    Water body could affect the thermal environment and airflow field in the building districts, because of its special thermal characteristics, evaporation and flat surface. The thermal influence of water body in Tongji University Jiading Campus front area was evaluated. First, a suitable evaporation model was selected and then was applied to calculate the boundary conditions of the water surface in the Fluent software. Next, the computational fluid dynamics (CFD) simulations were conducted on the models both with and without water, following the CFD practices guidelines. Finally, the outputs of the two simulations were compared with each other. Results showed that the effect of evaporative cooling from water surface strongly depends on the wind direction and temperature decrease was about 2∼5°C. The relative humidity within the enclosing area was affected by both the building arrangement and surrounding water. An increase of about 0.1∼0.2m/s of wind speed induced by the water evaporation was observed in the open space.

  15. Indirect contact freeze water desalination for an ice maker machine - CFD simulation

    NASA Astrophysics Data System (ADS)

    Jayakody, Harith; Al-Dadah, Raya; Mahmoud, Saad

    2017-11-01

    To offer for potable water shortages, sea water desalination is a potential solution for the global rising demand for fresh water. The latent heat of fusion is about one-seventh the latent heat of vaporisation, thus indicating the benefit of lower energy consumption for the freeze desalination process. Limited literature is reported on computational fluid dynamics (CFD) on freeze desalination. Therefore, analysing and investigating thermodynamic processes are easily conducted by the powerful tool of CFD. A single unit of ice formation in an ice maker machine was modelled using ANSYS Fluent software three-dimensionally. Energy, species transport and solidification/melting modules were used in building the CFD model. Parametric analysis was conducted using the established CFD model to predict the effects of freezing temperature and the geometry of the ice maker machine; on ice production and the freezing time. Lower freezing temperatures allowed more ice production and faster freezing. Increasing the diameter and the length of the freezing tube enabled more ice to be produced.

  16. Irrigant flow within a prepared root canal using various flow rates: a Computational Fluid Dynamics study.

    PubMed

    Boutsioukis, C; Lambrianidis, T; Kastrinakis, E

    2009-02-01

    To study using computer simulation the effect of irrigant flow rate on the flow pattern within a prepared root canal, during final irrigation with a syringe and needle. Geometrical characteristics of a side-vented endodontic needle and clinically realistic flow rate values were obtained from previous and preliminary studies. A Computational Fluid Dynamics (CFD) model was created using FLUENT 6.2 software. Calculations were carried out for five selected flow rates (0.02-0.79 mL sec(-1)) and velocity and turbulence quantities along the domain were evaluated. Irrigant replacement was limited to 1-1.5 mm apical to the needle tip for all flow rates tested. Low-Reynolds number turbulent flow was detected near the needle outlet. Irrigant flow rate affected significantly the flow pattern within the root canal. Irrigation needles should be placed to within 1 mm from working length to ensure fluid exchange. Turbulent flow of irrigant leads to more efficient irrigant replacement. CFD represents a powerful tool for the study of irrigation.

  17. A parametric simulation of solar chimney power plant

    NASA Astrophysics Data System (ADS)

    Beng Hooi, Lim; Kannan Thangavelu, Saravana

    2018-01-01

    The strong solar radiation, continuous supplies of sunlight and environmental friendly factors have made the solar chimney power plant becoming highly feasible to build in Malaysia. Solar chimney power plant produces upward buoyancy force through the greenhouse effect. Numerical simulation was performed on the model of a solar chimney power plant using the ANSYS Fluent software by applying standard k-epsilon turbulence model and discrete ordinates (DO) radiation model to solve the relevant equations. A parametric study was carried out to evaluate the performance of solar chimney power plant, which focused on the temperature rise in the collector, air velocity at the chimney base, and pressure drop inside the chimney were based on the results of temperature, velocity, and static pressure distributions. The results demonstrate reliability by comparing a model with the experimental data of Manzanares Spanish prototype. Based on the numerical results, power capacity and efficiency were analysed theoretically. Results indicate that a stronger solar radiation and larger prototype will improve the performance of solar chimney power plant.

  18. The necessity of HVAC system for the registered architectural cultural heritage building

    NASA Astrophysics Data System (ADS)

    Popovici, Cătălin George; Hudişteanu, Sebastian Valeriu; Cherecheş, Nelu-Cristian

    2018-02-01

    This study is intended to highlight the role of the ventilation and air conditioning system for a theatre. It was chosen as a case study the "Vasile Alecsandri" National Theatre of Jassy. The paper also sought to make a comparison in three distinct scenarios for HVAC Main Hall system - ventilation and air conditioning system of the Main Hall doesn't work; only the ventilation system of the Main Hall works and ventilation and air conditioning system of the Main Hall works. For analysing the comfort parameters, the ANSYS-Fluent software was used to build a 2D model of the building and simulation of HVAC system functionality during winter season, in all three scenarios. For the studied scenarios, the external conditions of Jassy and the indoor conditions of the theatre, when the entire spectacle hall is occupied were considered. The main aspects evaluated for each case were the air temperature, air velocity and relative humidity. The results are presented comparatively as plots and spectra of the interest parameters.

  19. Making On-line Science Course Materials Easily Translatable and Accessible Worldwide: Challenges and Solutions

    NASA Astrophysics Data System (ADS)

    Adams, Wendy K.; Alhadlaq, Hisham; Malley, Christopher V.; Perkins, Katherine K.; Olson, Jonathan; Alshaya, Fahad; Alabdulkareem, Saleh; Wieman, Carl E.

    2012-02-01

    The PhET Interactive Simulations Project partnered with the Excellence Research Center of Science and Mathematics Education at King Saud University with the joint goal of making simulations useable worldwide. One of the main challenges of this partnership is to make PhET simulations and the website easily translatable into any language. The PhET project team overcame this challenge by creating the Translation Utility. This tool allows a person fluent in both English and another language to easily translate any of the PhET simulations and requires minimal computer expertise. In this paper we discuss the technical issues involved in this software solution, as well as the issues involved in obtaining accurate translations. We share our solutions to many of the unexpected problems we encountered that would apply generally to making on-line scientific course materials available in many different languages, including working with: languages written right-to-left, different character sets, and different conventions for expressing equations, variables, units and scientific notation.

  20. Comparative study on direct burning of oil shale and coal

    NASA Astrophysics Data System (ADS)

    Hammad, Ahmad; Al Asfar, Jamil

    2017-07-01

    A comparative study of the direct burning processes of oil shale and coal in a circulating fluidized bed (CFB) was done in this study using ANSYS Fluent software to solve numerically the governing equations of continuity, momentum, energy and mass diffusion using finite volume method. The model was built based on an existing experimental combustion burner unit. The model was validated by comparing the theoretical results of oil shale with proved experimental results from the combustion unit. It was found that the temperature contours of the combustion process showed that the adiabatic flame temperature was 1080 K for oil shale compared with 2260 K for coal, while the obtained experimental results of temperatures at various locations of burner during the direct burning of oil shale showed that the maximum temperature reached 962 K for oil shale. These results were used in economic and environmental analysis which show that oil shale may be used as alternative fuel for coal in cement industry in Jordan.

  1. Study on Gap Flow Field Simulation in Small Hole Machining of Ultrasonic Assisted EDM

    NASA Astrophysics Data System (ADS)

    Liu, Yu; Chang, Hao; Zhang, Wenchao; Ma, Fujian; Sha, Zhihua; Zhang, Shengfang

    2017-12-01

    When machining a small hole with high aspect ratio in EDM, it is hard for the flushing liquid entering the bottom gap and the debris could hardly be removed, which results in the accumulation of debris and affects the machining efficiency and machining accuracy. The assisted ultrasonic vibration can improve the removal of debris in the gap. Based on dynamics simulation software Fluent, a 3D model of debris movement in the gap flow field of EDM small hole machining assisted with side flushing and ultrasonic vibration is established in this paper. When depth to ratio is 3, the laws of different amplitudes and frequencies on debris distribution and removal are quantitatively analysed. The research results show that periodic ultrasonic vibration can promote the movement of debris, which is beneficial to the removal of debris in the machining gap. Compared to traditional small hole machining in EDM, the debris in the machining gap is greatly reduced, which ensures the stability of machining process and improves the machining efficiency.

  2. Simulation studies on the standing and traveling wave thermoacoustic prime movers

    NASA Astrophysics Data System (ADS)

    Skaria, Mathew; Rasheed, K. K. Abdul; Shafi, K. A.; Kasthurirengan, S.; Behera, Upendra

    2014-01-01

    Thermoacoustic systems have been a focus of recent research due to its structural simplicity, high reliability due to absence of moving parts, and can be driven by low grade energy such as fuel, gas, solar energy, waste heat etc. There has been extensive research on both standing wave and traveling wave systems. Towards the development of such systems, simulations can be carried out by several methods such as (a) solving the energy equation, (b) enthalpy flow model, (c) DeltaEC, a free software available from LANL, USA (d) Computational Fluid Dynamics (CFD) etc. We present here the simulation studies of standing wave and traveling wave thermoacoustic prime movers using CFD and DeltaEC. The CFD analysis is carried out using Fluent 6.3.26, incorporating the necessary boundary conditions with different working fluids at different operating pressures. The results obtained by CFD are compared with those obtained using DeltaEC. Also, the CFD simulation of the thermoacoustically driven refrigerator is presented.

  3. Numerical simulation on the powder propellant pickup characteristics of feeding system at high pressure

    NASA Astrophysics Data System (ADS)

    Sun, Haijun; Hu, Chunbo; Zhu, Xiaofei

    2017-10-01

    A numerical study of powder propellant pickup progress at high pressure was presented in this paper by using two-fluid model with kinetic theory of granular flow in the computational fluid dynamics software package ANSYS/Fluent. Simulations were conducted to evaluate the effects of initial pressure, initial powder packing rate and mean particle diameter on the flow characteristics in terms of velocity vector distribution, granular temperature, pressure drop, particle velocity and volume. The numerical results of pressure drop were also compared with experiments to verify the TFM model. The simulated results show that the pressure drop value increases as the initial pressure increases, and the granular temperature under the conditions of different initial pressures and packing rates is almost the same in the area of throttling orifice plate. While there is an appropriate value for particle size and packing rate to form a ;core-annulus; structure in powder box, and the time-averaged velocity vector distribution of solid phase is inordinate.

  4. Simulation studies on the standing and traveling wave thermoacoustic prime movers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Skaria, Mathew; Rasheed, K. K. Abdul; Shafi, K. A.

    Thermoacoustic systems have been a focus of recent research due to its structural simplicity, high reliability due to absence of moving parts, and can be driven by low grade energy such as fuel, gas, solar energy, waste heat etc. There has been extensive research on both standing wave and traveling wave systems. Towards the development of such systems, simulations can be carried out by several methods such as (a) solving the energy equation, (b) enthalpy flow model, (c) DeltaEC, a free software available from LANL, USA (d) Computational Fluid Dynamics (CFD) etc. We present here the simulation studies of standingmore » wave and traveling wave thermoacoustic prime movers using CFD and DeltaEC. The CFD analysis is carried out using Fluent 6.3.26, incorporating the necessary boundary conditions with different working fluids at different operating pressures. The results obtained by CFD are compared with those obtained using DeltaEC. Also, the CFD simulation of the thermoacoustically driven refrigerator is presented.« less

  5. Making statistical inferences about software reliability

    NASA Technical Reports Server (NTRS)

    Miller, Douglas R.

    1988-01-01

    Failure times of software undergoing random debugging can be modelled as order statistics of independent but nonidentically distributed exponential random variables. Using this model inferences can be made about current reliability and, if debugging continues, future reliability. This model also shows the difficulty inherent in statistical verification of very highly reliable software such as that used by digital avionics in commercial aircraft.

  6. Technology Infusion of CodeSonar into the Space Network Ground Segment (RII07)

    NASA Technical Reports Server (NTRS)

    Benson, Markland

    2008-01-01

    The NASA Software Assurance Research Program (in part) performs studies as to the feasibility of technologies for improving the safety, quality, reliability, cost, and performance of NASA software. This study considers the application of commercial automated source code analysis tools to mission critical ground software that is in the operations and sustainment portion of the product lifecycle.

  7. Prete-moi Ton Logiciel pour Ecrire un Mot (Lend Me Your Software Program So I Can Write a Letter).

    ERIC Educational Resources Information Center

    Mangenot, Francois

    1993-01-01

    A brief discussion and description of one commercially available software package ("Pour Ecrire un Mot") for writing letters of various types uses the love letter as an example of the software's functioning. Answers to the prompting questions on the screen determine the few variable parameters of the text to be generated. (four…

  8. Controls Over Copyrighted Computer Software

    DTIC Science & Technology

    1993-02-19

    The Army Audit Agency issued five installation reports as a result of one multilocation audit . The audit found that 41 percent of the computers...ARMY AUDIT AGENCY REPORTS ON COMPUTER SOFTWARE MANAGEMENT The U.S. Army Audit Agency conducted three multilocation audits from March 1988 through...December 1990, covering the acquisition, use, control, and accountability of commercial software. One multilocation audit resulted in five

  9. SMC Message Browser Projects

    NASA Technical Reports Server (NTRS)

    Wichmann, Benjamin C.

    2013-01-01

    I work directly with the System Monitoring and Control (SMC) software engineers who develop, test and release custom and commercial software in support of the Kennedy Space Center Spaceport Command and Control System. (SCCS). SMC uses Commercial Off-The-Shelf (COTS) Enterprise Management Systems (EMS) software which provides a centralized subsystem for configuring, monitoring, and controlling SCCS hardware and software used in the Control Rooms. There are multiple projects being worked on using the COTS EMS software. I am currently working with the HP Operations Manager for UNIX (OMU) software which allows Master Console Operators (MCO) to access, view and interpret messages regarding the status of the SCCS hardware and software. The OMU message browser gets cluttered with messages which can make it difficult for the MCO to manage. My main project involves determining ways to reduce the number of messages being displayed in the OMU message browser. I plan to accomplish this task in two different ways: (1) by correlating multiple messages into one single message being displayed and (2) to create policies that will determine the significance of each message and whether or not it needs to be displayed to the MCO. The core idea is to lessen the number of messages being sent to the OMU message browser so the MCO can more effectively use it.

  10. Problem-Solving Software

    NASA Technical Reports Server (NTRS)

    1992-01-01

    CBR Express software solves problems by adapting sorted solutions to new problems specified by a user. It is applicable to a wide range of situations. The technology was originally developed by Inference Corporation for Johnson Space Center's Advanced Software Development Workstation. The project focused on the reuse of software designs, and Inference used CBR as part of the ACCESS prototype software. The commercial CBR Express is used as a "help desk" for customer support, enabling reuse of existing information when necessary. It has been adopted by several companies, among them American Airlines, which uses it to solve reservation system software problems.

  11. Bayesian Software Health Management for Aircraft Guidance, Navigation, and Control

    NASA Technical Reports Server (NTRS)

    Schumann, Johann; Mbaya, Timmy; Menghoel, Ole

    2011-01-01

    Modern aircraft, both piloted fly-by-wire commercial aircraft as well as UAVs, more and more depend on highly complex safety critical software systems with many sensors and computer-controlled actuators. Despite careful design and V&V of the software, severe incidents have happened due to malfunctioning software. In this paper, we discuss the use of Bayesian networks (BNs) to monitor the health of the on-board software and sensor system, and to perform advanced on-board diagnostic reasoning. We will focus on the approach to develop reliable and robust health models for the combined software and sensor systems.

  12. Quick Overview Scout 2008 Version 1.0

    EPA Science Inventory

    The Scout 2008 version 1.0 statistical software package has been updated from past DOS and Windows versions to provide classical and robust univariate and multivariate graphical and statistical methods that are not typically available in commercial or freeware statistical softwar...

  13. Hop, Skip and Jump: Animation Software.

    ERIC Educational Resources Information Center

    Eiser, Leslie

    1986-01-01

    Discusses the features of animation software packages, reviewing eight commercially available programs. Information provided for each program includes name, publisher, current computer(s) required, cost, documentation, input device, import/export capabilities, printing possibilities, what users can originate, types of image manipulation possible,…

  14. Post-treatment speech naturalness of comprehensive stuttering program clients and differences in ratings among listener groups.

    PubMed

    Teshima, Shelli; Langevin, Marilyn; Hagler, Paul; Kully, Deborah

    2010-03-01

    The purposes of this study were to investigate naturalness of the post-treatment speech of Comprehensive Stuttering Program (CSP) clients and differences in naturalness ratings by three listener groups. Listeners were 21 student speech-language pathologists, 9 community members, and 15 listeners who stutter. Listeners rated perceptually fluent speech samples of CSP clients obtained immediately post-treatment (Post) and at 5 years follow-up (F5), and speech samples of matched typically fluent (TF) speakers. A 9-point interval rating scale was used. A 3 (listener group)x2 (time)x2 (speaker) mixed ANOVA was used to test for differences among mean ratings. The difference between CSP Post and F5 mean ratings was statistically significant. The F5 mean rating was within the range reported for typically fluent speakers. Student speech-language pathologists were found to be less critical than community members and listeners who stutter in rating naturalness; however, there were no significant differences in ratings made by community members and listeners who stutter. Results indicate that the naturalness of post-treatment speech of CSP clients improves in the post-treatment period and that it is possible for clients to achieve levels of naturalness that appear to be acceptable to adults who stutter and that are within the range of naturalness ratings given to typically fluent speakers. Readers will be able to (a) summarize key findings of studies that have investigated naturalness ratings, and (b) interpret the naturalness ratings of Comprehensive Stuttering Program speaker samples and the ratings made by the three listener groups in this study.

  15. Autonomic arousal in adults who stutter prior to various reading tasks intended to elicit changes in stuttering frequency.

    PubMed

    Bowers, Andrew; Saltuklaroglu, Tim; Kalinowski, Joseph

    2012-01-01

    This study examined relationships between anticipatory autonomic arousal and stuttering in four reading tasks. 13 adult persons who stutter (PWS) reported their 'feared' (expected to elicit more stuttering) sounds. They read phrases initiated by feared (F) and neutral (N) phonemes. Both stimuli sets were read solo (S) and with choral accompaniment (C), creating FS, FC, NS, and NC conditions. Skin conductance (SC) and heart rate (HR) measures were made during a 9s window that followed stimulus presentation and preceded speaking. Only SC measures produced significant differences across conditions. Choral conditions produced decreases in SC measures and stuttered trials. Feared conditions produced increases in SC but not stuttering. HR measures were variable, undifferentiated by condition, but produced a gradually increasing triphasic response pattern. No differences in anticipatory SC or HR measures were found in stuttered versus fluent trial comparisons. However, the NC condition, which eliminated stuttering, produced significantly lower SC measures than the fluent utterances in the other conditions (FS, FC, NS). Furthermore, SC measures from the fluent and stuttered trials were similar in these three conditions. These findings suggest that anticipatory autonomic arousal is better differentiated by the possibility of stuttering than by a fluent/stuttered speech outcome. Trials that produced anticipatory SC responses showed greater final HR deceleration, suggesting autonomic coactivation, a response pattern that is associated with aversive stimuli and herein, likely indicative of speech-related state anxiety. However, these physiological markers of anxiety appear to be neither necessary nor sufficient to induce observable stuttering. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. Comparison of upper and lower lip muscle activity between stutterers and fluent speakers.

    PubMed

    de Felício, Cláudia Maria; Freitas, Rosana Luiza Rodrigues Gomes; Vitti, Mathias; Regalo, Simone Cecilio Hallak

    2007-08-01

    There is a widespread clinical view that stuttering is associated with high levels of muscles activity. The proposal of this research was to compare stutterers and fluent speakers with respect to the electromyographic activity of the upper and lower lip muscles. Ten individuals who stutter and 10 fluent speakers (control group) paired by gender and age were studied (mean age: 13.4 years). Groups were defined by the speech sample analysis of the ABFW-Language Test. A K6-I EMG (Myo-tronics Co., Seattle, WA, USA) with double disposable silver electrodes (Duotrodes, Myo-tronics Co., Seattle, WA) being used in order to analyze lip muscle activity. The clinical conditions investigated were movements during speech, orofacial non-speech tasks, and rest. Electromyographic data were normalized by lip pursing activity. The non-parametric Mann-Whitney test was used for the comparison of speech fluency profile, and the Student t-test for independent samples for group comparison regarding electromyographic data. There was a statistically significant difference between groups regarding speech fluency profile and upper lip activity in the following conditions: lip lateralization to the right and to the left and rest before exercises (P<0.05). There was no significant difference between groups regarding lower lip activity (P>0.05). The EMG activity of the upper lip muscle in the group with stuttering was significantly lower than in the control group in some of the clinical conditions analyzed. There was no significant difference between groups regarding the lower lip muscle. The subjects who stutter did not present higher levels of muscle activity in lip muscles than fluent speakers.

  17. Spectral Coefficient Analyses of Word-Initial Stop Consonant Productions Suggest Similar Anticipatory Coarticulation for Stuttering and Nonstuttering Adults.

    PubMed

    Maruthy, Santosh; Feng, Yongqiang; Max, Ludo

    2018-03-01

    A longstanding hypothesis about the sensorimotor mechanisms underlying stuttering suggests that stuttered speech dysfluencies result from a lack of coarticulation. Formant-based measures of either the stuttered or fluent speech of children and adults who stutter have generally failed to obtain compelling evidence in support of the hypothesis that these individuals differ in the timing or degree of coarticulation. Here, we used a sensitive acoustic technique-spectral coefficient analyses-that allowed us to compare stuttering and nonstuttering speakers with regard to vowel-dependent anticipatory influences as early as the onset burst of a preceding voiceless stop consonant. Eight adults who stutter and eight matched adults who do not stutter produced C 1 VC 2 words, and the first four spectral coefficients were calculated for one analysis window centered on the burst of C 1 and two subsequent windows covering the beginning of the aspiration phase. Findings confirmed that the combined use of four spectral coefficients is an effective method for detecting the anticipatory influence of a vowel on the initial burst of a preceding voiceless stop consonant. However, the observed patterns of anticipatory coarticulation showed no statistically significant differences, or trends toward such differences, between the stuttering and nonstuttering groups. Combining the present results for fluent speech in one given phonetic context with prior findings from both stuttered and fluent speech in a variety of other contexts, we conclude that there is currently no support for the hypothesis that the fluent speech of individuals who stutter is characterized by limited coarticulation.

  18. Theoretical study of nanoparticle formation in thermal plasma processing: Nucleation, coagulation and aggregation

    NASA Astrophysics Data System (ADS)

    Mendoza Gonzalez, Norma Yadira

    This work presents a mathematical modeling study of the synthesis of nanoparticles in radio frequency (RF) inductively coupled plasma (ICP) reactors. The purpose is to further investigate the influence of process parameters on the final size and morphology of produced particles. The proposed model involves the calculation of flow and temperature fields of the plasma gas. Evaporation of raw particles is also accounted with the particle trajectory and temperature history calculated with a Lagrangian approach. The nanoparticle formation is considered by homogeneous nucleation and the growth is caused by condensation and Brownian coagulation. The growth of fractal aggregates is considered by introducing a power law exponent Df. Transport of nanoparticles occurs by convection, thermophoresis and Brownian diffusion. The method of moments is used to solve the particle dynamics equation. The model is validated using experimental results from plasma reactors at laboratory scale. The results are presented in the following manner. First, use is made of the computational fluid dynamics software (CFD), Fluent 6.1 with a commercial companion package specifically developped for aerosols named: Fine Particle Model (FPM). This package is used to study the relationship between the operating parameters effect and the properties of the end products at the laboratory scale. Secondly, a coupled hybrid model for the synthesis of spherical particles and fractal aggregates is developped in place of the FPM package. Results obtained from this model will allow to identify the importance of each parameter in defining the morphology of spherical primary particles and fractal aggregates of nanoparticles. The solution of the model was made using the geometries and operating conditions of existing reactors at the Centre de Recherche en Energie, Plasma et Electrochimie (CREPE) of the Universite de Sherbrooke, for which experimental results were obtained experimentally. Additionally, this study demonstrates the importance of the flow and temperature fields on the growth of fractal particles; namely the aggregates.

  19. A Numerical Simulation of Transport Phenomena During the Horizontal Single Belt Casting Process Using an Inclined Feeding System

    NASA Astrophysics Data System (ADS)

    Xu, Mianguang; Isac, Mihaiela; Guthrie, Roderick I. L.

    2018-03-01

    Horizontal single belt casting (HSBC) has great potential to replace current conventional continuous casting (CCC) processes for sheet metal production, by directly casting 3 to 1 mm sheet for the automobile industry. In the present paper, two-dimensional mathematical models were developed to study transport phenomena, for the case of an inclined wall feeding system for a liquid aluminum wrought alloy (AA6111). Based on the commercial software ANSYS FLUENT 14.5 and user-defined functions, a two-layer turbulence model was used to examine the fluid flow emanating from a slot nozzle set above a water-cooled, high-speed, steel belt. The Volume of Fluid (VOF) method was used to predict the shape of the melt-air interface. A transformed coordinate system (x', y') was established in order to analyze the fluid flow on the inclined wall of the feeding system. The total pressure gauge gradient (∂p total/∂x) was used to describe the behavior of the melt film inside the slot nozzle of the head box. The modeling results show that during the melt film falling process, the total gauge pressure varies within the slot nozzle, which can decrease the stability of the falling film. The first impingement between the falling film and the inclined refractory wall of the feeding system gives rise to a local oscillation, and this influences the stability of the melt film moving downwards. At the rear meniscus position between the inclined wall and the moving belt, there is a clear vibration of the air-melt interface, together with a recirculation zone. The weak vibration of the air-melt interface could be induced by the periodic variation of the melt-air interface. Moreover, the formation of tiny air pockets is predicted. Finally, on the inclined wall of the feeding system, a suitable length of the transition area is needed to avoid over-acceleration of the melt film due to the force of gravity.

  20. A Numerical Simulation of Transport Phenomena During the Horizontal Single Belt Casting Process Using an Inclined Feeding System

    NASA Astrophysics Data System (ADS)

    Xu, Mianguang; Isac, Mihaiela; Guthrie, Roderick I. L.

    2018-06-01

    Horizontal single belt casting (HSBC) has great potential to replace current conventional continuous casting (CCC) processes for sheet metal production, by directly casting 3 to 1 mm sheet for the automobile industry. In the present paper, two-dimensional mathematical models were developed to study transport phenomena, for the case of an inclined wall feeding system for a liquid aluminum wrought alloy (AA6111). Based on the commercial software ANSYS FLUENT 14.5 and user-defined functions, a two-layer turbulence model was used to examine the fluid flow emanating from a slot nozzle set above a water-cooled, high-speed, steel belt. The Volume of Fluid (VOF) method was used to predict the shape of the melt-air interface. A transformed coordinate system ( x', y') was established in order to analyze the fluid flow on the inclined wall of the feeding system. The total pressure gauge gradient ( ∂p total/ ∂x) was used to describe the behavior of the melt film inside the slot nozzle of the head box. The modeling results show that during the melt film falling process, the total gauge pressure varies within the slot nozzle, which can decrease the stability of the falling film. The first impingement between the falling film and the inclined refractory wall of the feeding system gives rise to a local oscillation, and this influences the stability of the melt film moving downwards. At the rear meniscus position between the inclined wall and the moving belt, there is a clear vibration of the air-melt interface, together with a recirculation zone. The weak vibration of the air-melt interface could be induced by the periodic variation of the melt-air interface. Moreover, the formation of tiny air pockets is predicted. Finally, on the inclined wall of the feeding system, a suitable length of the transition area is needed to avoid over-acceleration of the melt film due to the force of gravity.

  1. Optimal hydraulic design of new-type shaft tubular pumping system

    NASA Astrophysics Data System (ADS)

    Zhu, H. G.; Zhang, R. T.; Zhou, J. R.

    2012-11-01

    Based on the characteristics of large flow rate, low-head, short annual operation time and high reliability of city flood-control pumping stations, a new-type shaft tubular pumping system featuring shaft suction box, siphon-type discharge passage with vacuum breaker as cutoff device was put forward, which possesses such advantages as simpler structure, reliable cutoff and higher energy performance. According to the design parameters of a city flood control pumping station, a numerical computation model was set up including shaft-type suction box, siphon-type discharge passage, pump impeller and guide vanes. By using commercial CFD software Fluent, RNG κ-epsilon turbulence model was adopted to close the three-dimensional time-averaged incompressible N-S equations. After completing optimal hydraulic design of shaft-type suction box, and keeping the parameters of total length, maximum width and outlet section unchanged, siphon-type discharge passages of three hump locations and three hump heights were designed and numerical analysis on the 9 hydraulic design schemes of pumping system were proceeded. The computational results show that the changing of hump locations and hump heights directly affects the internal flow patterns of discharge passages and hydraulic performances of the system, and when hump is located 3.66D from the inlet section and hump height is about 0.65D (D is the diameter of pump impeller), the new-type shaft tubular pumping system achieves better energy performances. A pumping system model test of the optimal designed scheme was carried out. The result shows that the highest pumping system efficiency reaches 75.96%, and when at design head of 1.15m the flow rate and system efficiency were 0.304m3/s and 63.10%, respectively. Thus, the validity of optimal design method was verified by the model test, and a solid foundation was laid for the application and extension of the new-type shaft tubular pumping system.

  2. Numerical Studies of Flow Past Two Side-by-Side Circular Cylinders

    NASA Astrophysics Data System (ADS)

    Shao, J.; Zhang, C.

    Multiple circular cylindrical configurations are widely used in engineering applications. The fluid dynamics of the flow around two identical circular cylinders in side-by-side arrangement has been investigated by both experiments and numerical simulations. The center-to-center transverse pitch ratio T/D plays an important role in determining the flow features. It is observed that for 1 < T/D < 1.1 to 1.2, a single vortex street is formed; for 1.2< T/D < 2 to 2.2, bi-stable narrow and wide wakes are formed; for 2.7< T/D < 4 or 5, anti-phase or in-phase vortex streets are formed. In the current study, the vortex structures of turbulent flows past two slightly heated side-by-side circular cylinders are investigated employing the large eddy simulation (LES). Simulations are performed using a commercial CFD software, FLUENT. The Smagorinsky-Lilly subgrid-scale model is employed for the large eddy simulation. The Reynolds number based on free-stream velocity and cylinder diameter is 5 800, which is in the subcritical regime. The transverse pitch ratio T/D = 3 is investigated. Laminar boundary layer, transition in shear layer, flow separation, large vortex structures and flow interference in the wake are all involved in the flow. Such complex flow features make the current study a challenging task. Both flow field and temperature field are investigated. The calculated results are analyzed and compared with experimental data. The simulation results are qualitatively in accordance with experimental observations. Two anti-phase vortex streets are obtained by the large-eddy simulation, which agrees with the experimental observation. At this transverse pitch ratio, these two cylinders behave as independent, isolated single cylinder in cross flow. The time-averaged streamwise velocity and temperature at x/D=10 are in good agreement with the experimental data. Figure1 displays the instantaneous spanwise vorticity at the center plane.

  3. Making Sense of Remotely Sensed Ultra-Spectral Infrared Data

    NASA Technical Reports Server (NTRS)

    2001-01-01

    NASA's Jet Propulsion Laboratory (JPL), Pasadena, California, Earth Observing System (EOS) programs, the Deep Space Network (DSN), and various Department of Defense (DOD) technology demonstration programs, combined their technical expertise to develop SEASCRAPE, a software program that obtains data when thermal infrared radiation passes through the Earth's atmosphere and reaches a sensor. Licensed by the California Institute of Technology (Caltech), SEASCRAPE automatically inverts complex infrared data and makes it possible to obtain estimates of the state of the atmosphere along the ray path. Former JPL staff members created a small entrepreneurial firm, Remote Sensing Analysis Systems, Inc., of Altadena, California, to commercialize the product. The founders believed that a commercial version of the software was needed for future U.S. government missions and the commercial monitoring of pollution. With the inversion capability of this software and remote sensing instrumentation, it is possible to monitor pollution sources from safe and secure distances on a noninterfering, noncooperative basis. The software, now know as SEASCRAPE_Plus, allows the user to determine the presence of pollution products, their location and their abundance along the ray path. The technology has been cleared by the Department of Commerce for export, and is currently used by numerous research and engineering organizations around the world.

  4. Comparison of methods for quantitative evaluation of endoscopic distortion

    NASA Astrophysics Data System (ADS)

    Wang, Quanzeng; Castro, Kurt; Desai, Viraj N.; Cheng, Wei-Chung; Pfefer, Joshua

    2015-03-01

    Endoscopy is a well-established paradigm in medical imaging, and emerging endoscopic technologies such as high resolution, capsule and disposable endoscopes promise significant improvements in effectiveness, as well as patient safety and acceptance of endoscopy. However, the field lacks practical standardized test methods to evaluate key optical performance characteristics (OPCs), in particular the geometric distortion caused by fisheye lens effects in clinical endoscopic systems. As a result, it has been difficult to evaluate an endoscope's image quality or assess its changes over time. The goal of this work was to identify optimal techniques for objective, quantitative characterization of distortion that are effective and not burdensome. Specifically, distortion measurements from a commercially available distortion evaluation/correction software package were compared with a custom algorithm based on a local magnification (ML) approach. Measurements were performed using a clinical gastroscope to image square grid targets. Recorded images were analyzed with the ML approach and the commercial software where the results were used to obtain corrected images. Corrected images based on the ML approach and the software were compared. The study showed that the ML method could assess distortion patterns more accurately than the commercial software. Overall, the development of standardized test methods for characterizing distortion and other OPCs will facilitate development, clinical translation, manufacturing quality and assurance of performance during clinical use of endoscopic technologies.

  5. Software Smarts

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Under an SBIR (Small Business Innovative Research) contract with Johnson Space Center, Knowledge Based Systems Inc. (KBSI) developed an intelligent software environment for modeling and analyzing mission planning activities, simulating behavior, and, using a unique constraint propagation mechanism, updating plans with each change in mission planning activities. KBSI developed this technology into a commercial product, PROJECTLINK, a two-way bridge between PROSIm, KBSI's process modeling and simulation software and leading project management software like Microsoft Project and Primavera's SureTrak Project Manager.

  6. Audiovisual speech integration in the superior temporal region is dysfunctional in dyslexia.

    PubMed

    Ye, Zheng; Rüsseler, Jascha; Gerth, Ivonne; Münte, Thomas F

    2017-07-25

    Dyslexia is an impairment of reading and spelling that affects both children and adults even after many years of schooling. Dyslexic readers have deficits in the integration of auditory and visual inputs but the neural mechanisms of the deficits are still unclear. This fMRI study examined the neural processing of auditorily presented German numbers 0-9 and videos of lip movements of a German native speaker voicing numbers 0-9 in unimodal (auditory or visual) and bimodal (always congruent) conditions in dyslexic readers and their matched fluent readers. We confirmed results of previous studies that the superior temporal gyrus/sulcus plays a critical role in audiovisual speech integration: fluent readers showed greater superior temporal activations for combined audiovisual stimuli than auditory-/visual-only stimuli. Importantly, such an enhancement effect was absent in dyslexic readers. Moreover, the auditory network (bilateral superior temporal regions plus medial PFC) was dynamically modulated during audiovisual integration in fluent, but not in dyslexic readers. These results suggest that superior temporal dysfunction may underly poor audiovisual speech integration in readers with dyslexia. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  7. It felt fluent, and I liked it: subjective feeling of fluency rather than objective fluency determines liking.

    PubMed

    Forster, Michael; Leder, Helmut; Ansorge, Ulrich

    2013-04-01

    According to the processing-fluency explanation of aesthetics, more fluently processed stimuli are preferred (R. Reber, N. Schwarz, & P. Winkielman, 2004, Processing fluency and aesthetic pleasure: Is beauty in the perceiver's processing experience? Personality and Social Psychology Review, Vol. 8, pp. 364-382.). In this view, the subjective feeling of ease of processing is considered important, but this has not been directly tested in perceptual processing. In two experiments, we therefore objectively manipulated fluency (ease of processing) with subliminal perceptual priming (Study 1) and variations in presentation durations (Study 2). We assessed the impact of objective fluency on feelings of fluency and liking, as well as their interdependence. In line with the processing-fluency account, we found that objectively more fluent images were indeed judged as more fluent and were also liked more. Moreover, differences in liking were even stronger when data were analyzed according to felt fluency. These findings demonstrate that perceptual fluency is not only explicitly felt, it can also be reported and is an important determinant of liking. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  8. The Contribution of Phonological Awareness to Reading Fluency and Its Individual Sub-skills in Readers Aged 9- to 12-years

    PubMed Central

    Elhassan, Zena; Crewther, Sheila G.; Bavin, Edith L.

    2017-01-01

    Research examining phonological awareness (PA) contributions to reading in established readers of different skill levels is limited. The current study examined the contribution of PA to phonological decoding, visual word recognition, reading rate, and reading comprehension in 124 fourth to sixth grade children (aged 9–12 years). On the basis of scores on the FastaReada measure of reading fluency participants were allocated to one of three reading ability categories: dysfluent (n = 47), moderate (n = 38) and fluent (n = 39). For the dysfluent group, PA contributed significantly to all reading measures except rate, but in the moderate group only to phonological decoding. PA did not influence performances on any of the reading measures examined for the fluent reader group. The results support the notion that fluency is characterized by a shift from conscious decoding to rapid and accurate visual recognition of words. Although PA may be influential in reading development, the results of the current study show that it is not sufficient for fluent reading. PMID:28443048

  9. The Contribution of Phonological Awareness to Reading Fluency and Its Individual Sub-skills in Readers Aged 9- to 12-years.

    PubMed

    Elhassan, Zena; Crewther, Sheila G; Bavin, Edith L

    2017-01-01

    Research examining phonological awareness (PA) contributions to reading in established readers of different skill levels is limited. The current study examined the contribution of PA to phonological decoding, visual word recognition, reading rate, and reading comprehension in 124 fourth to sixth grade children (aged 9-12 years). On the basis of scores on the FastaReada measure of reading fluency participants were allocated to one of three reading ability categories: dysfluent ( n = 47), moderate ( n = 38) and fluent ( n = 39). For the dysfluent group, PA contributed significantly to all reading measures except rate, but in the moderate group only to phonological decoding. PA did not influence performances on any of the reading measures examined for the fluent reader group. The results support the notion that fluency is characterized by a shift from conscious decoding to rapid and accurate visual recognition of words. Although PA may be influential in reading development, the results of the current study show that it is not sufficient for fluent reading.

  10. Numerical study of influences of crosswind and additional steam on the flow field and temperature of propane non-premixed turbulence flame

    NASA Astrophysics Data System (ADS)

    Wusnah; Bindar, Y.; Yunardi; Nur, F. M.; Syam, A. M.

    2018-03-01

    This paper presents results the process of combustion propane using computational fluid dynamics (CFD) to simulate the turbulent non-premixed flame under the influences of crosswinds and the ratio of fuel (propane) to steam, S. Configuration, discretization and boundary conditions of the flame are described using GambitTM software and integrated with FluentTM software for calculations of flow and reactive fields. This work focuses on the influence of various crosswind speeds (0–10 m/s) and values of S (0.14–2.35) while the velocity of fuel issued from the nozzle was kept constant at 20 m/s. A turbulence model, k-ɛ standard and combustion model, Eddy Dissipation model were employed for the calculation of velocity and temperature fields, respectively. The results are displayed in the form of predictive terrain profile of the propane flame at different crosswind speeds. The results of the propane flame profile demonstrated that the crosswind significantly affect the structure velocity and position of the flame which was off-center moving towards the direction of crosswind, eventually affect the temperature along the flame. As the values of S is increasing, the flame contour temperature decreases, until the flame was extinguished at S equals to 2.35. The combustion efficiency for a variety of crosswind speeds decreases with increasing values of S.

  11. Calibration of a COTS Integration Cost Model Using Local Project Data

    NASA Technical Reports Server (NTRS)

    Boland, Dillard; Coon, Richard; Byers, Kathryn; Levitt, David

    1997-01-01

    The software measures and estimation techniques appropriate to a Commercial Off the Shelf (COTS) integration project differ from those commonly used for custom software development. Labor and schedule estimation tools that model COTS integration are available. Like all estimation tools, they must be calibrated with the organization's local project data. This paper describes the calibration of a commercial model using data collected by the Flight Dynamics Division (FDD) of the NASA Goddard Spaceflight Center (GSFC). The model calibrated is SLIM Release 4.0 from Quantitative Software Management (QSM). By adopting the SLIM reuse model and by treating configuration parameters as lines of code, we were able to establish a consistent calibration for COTS integration projects. The paper summarizes the metrics, the calibration process and results, and the validation of the calibration.

  12. The 1993-94 Educational Software Preview Guide.

    ERIC Educational Resources Information Center

    Best, Anita, Ed.; Mathis, Judi, Ed.

    This guide lists favorably reviewed, commercially available, microcomputer software for instructional use in preschool through grade 12. The guide is organized by the following curriculum areas: art; business education; computers; health; instructional tools, including authoring systems, computer assisted drafting (CAD), classroom management,…

  13. Scout 2008 Version 1.0 User Guide

    EPA Science Inventory

    The Scout 2008 version 1.0 software package provides a wide variety of classical and robust statistical methods that are not typically available in other commercial software packages. A major part of Scout deals with classical, robust, and resistant univariate and multivariate ou...

  14. Platform-Independent Cirrus and Spectralis Thickness Measurements in Eyes with Diabetic Macular Edema Using Fully Automated Software

    PubMed Central

    Willoughby, Alex S.; Chiu, Stephanie J.; Silverman, Rachel K.; Farsiu, Sina; Bailey, Clare; Wiley, Henry E.; Ferris, Frederick L.; Jaffe, Glenn J.

    2017-01-01

    Purpose We determine whether the automated segmentation software, Duke Optical Coherence Tomography Retinal Analysis Program (DOCTRAP), can measure, in a platform-independent manner, retinal thickness on Cirrus and Spectralis spectral domain optical coherence tomography (SD-OCT) images in eyes with diabetic macular edema (DME) under treatment in a clinical trial. Methods Automatic segmentation software was used to segment the internal limiting membrane (ILM), inner retinal pigment epithelium (RPE), and Bruch's membrane (BM) in SD-OCT images acquired by Cirrus and Spectralis commercial systems, from the same eye, on the same day during a clinical interventional DME trial. Mean retinal thickness differences were compared across commercial and DOCTRAP platforms using intraclass correlation (ICC) and Bland-Altman plots. Results The mean 1 mm central subfield thickness difference (standard error [SE]) comparing segmentation of Spectralis images with DOCTRAP versus HEYEX was 0.7 (0.3) μm (0.2 pixels). The corresponding values comparing segmentation of Cirrus images with DOCTRAP versus Cirrus software was 2.2 (0.7) μm. The mean 1 mm central subfield thickness difference (SE) comparing segmentation of Cirrus and Spectralis scan pairs with DOCTRAP using BM as the outer retinal boundary was −2.3 (0.9) μm compared to 2.8 (0.9) μm with inner RPE as the outer boundary. Conclusions DOCTRAP segmentation of Cirrus and Spectralis images produces validated thickness measurements that are very similar to each other, and very similar to the values generated by the corresponding commercial software in eyes with treated DME. Translational Relevance This software enables automatic total retinal thickness measurements across two OCT platforms, a process that is impractical to perform manually. PMID:28180033

  15. Developing an Interactive Data Visualization Tool to Assess the Impact of Decision Support on Clinical Operations.

    PubMed

    Huber, Timothy C; Krishnaraj, Arun; Monaghan, Dayna; Gaskin, Cree M

    2018-05-18

    Due to mandates from recent legislation, clinical decision support (CDS) software is being adopted by radiology practices across the country. This software provides imaging study decision support for referring providers at the point of order entry. CDS systems produce a large volume of data, providing opportunities for research and quality improvement. In order to better visualize and analyze trends in this data, an interactive data visualization dashboard was created using a commercially available data visualization platform. Following the integration of a commercially available clinical decision support product into the electronic health record, a dashboard was created using a commercially available data visualization platform (Tableau, Seattle, WA). Data generated by the CDS were exported from the data warehouse, where they were stored, into the platform. This allowed for real-time visualization of the data generated by the decision support software. The creation of the dashboard allowed the output from the CDS platform to be more easily analyzed and facilitated hypothesis generation. Integrating data visualization tools into clinical decision support tools allows for easier data analysis and can streamline research and quality improvement efforts.

  16. Scrum and Global Delivery: Pitfalls and Lessons Learned

    NASA Astrophysics Data System (ADS)

    Sadun, Cristiano

    Two trends are becoming widespread in software development work—agile development processes and global delivery, both promising sizable benefits in productivity, capacity and so on. Combining the two is a highly attractive possibility, even more so in fast-paced and constrained commercial software engineering projects. However, a degree of conflict exists between the assumptions underlying the two ideas, leading to pitfalls and challenges in agile/distributed projects which are new, both with respect to traditional development and agile or distributed efforts adopted separately. Succeeding in commercial agile/distributed projects implies recognizing these new challenges, proactively planning for them, and actively put in place solutions and methods to overcome them. This chapter illustrates some of the typical challenges that were met during real-world commercial projects, and how they were solved.

  17. Healthy brain connectivity predicts atrophy progression in non-fluent variant of primary progressive aphasia.

    PubMed

    Mandelli, Maria Luisa; Vilaplana, Eduard; Brown, Jesse A; Hubbard, H Isabel; Binney, Richard J; Attygalle, Suneth; Santos-Santos, Miguel A; Miller, Zachary A; Pakvasa, Mikhail; Henry, Maya L; Rosen, Howard J; Henry, Roland G; Rabinovici, Gil D; Miller, Bruce L; Seeley, William W; Gorno-Tempini, Maria Luisa

    2016-10-01

    Neurodegeneration has been hypothesized to follow predetermined large-scale networks through the trans-synaptic spread of toxic proteins from a syndrome-specific epicentre. To date, no longitudinal neuroimaging study has tested this hypothesis in vivo in frontotemporal dementia spectrum disorders. The aim of this study was to demonstrate that longitudinal progression of atrophy in non-fluent/agrammatic variant primary progressive aphasia spreads over time from a syndrome-specific epicentre to additional regions, based on their connectivity to the epicentre in healthy control subjects. The syndrome-specific epicentre of the non-fluent/agrammatic variant of primary progressive aphasia was derived in a group of 10 mildly affected patients (clinical dementia rating equal to 0) using voxel-based morphometry. From this region, the inferior frontal gyrus (pars opercularis), we derived functional and structural connectivity maps in healthy controls (n = 30) using functional magnetic resonance imaging at rest and diffusion-weighted imaging tractography. Graph theory analysis was applied to derive functional network features. Atrophy progression was calculated using voxel-based morphometry longitudinal analysis on 34 non-fluent/agrammatic patients. Correlation analyses were performed to compare volume changes in patients with connectivity measures of the healthy functional and structural speech/language network. The default mode network was used as a control network. From the epicentre, the healthy functional connectivity network included the left supplementary motor area and the prefrontal, inferior parietal and temporal regions, which were connected through the aslant, superior longitudinal and arcuate fasciculi. Longitudinal grey and white matter changes were found in the left language-related regions and in the right inferior frontal gyrus. Functional connectivity strength in the healthy speech/language network, but not in the default network, correlated with longitudinal grey matter changes in the non-fluent/agrammatic variant of primary progressive aphasia. Graph theoretical analysis of the speech/language network showed that regions with shorter functional paths to the epicentre exhibited greater longitudinal atrophy. The network contained three modules, including a left inferior frontal gyrus/supplementary motor area, which was most strongly connected with the epicentre. The aslant tract was the white matter pathway connecting these two regions and showed the most significant correlation between fractional anisotropy and white matter longitudinal atrophy changes. This study showed that the pattern of longitudinal atrophy progression in the non-fluent/agrammatic variant of primary progressive aphasia relates to the strength of connectivity in pre-determined functional and structural large-scale speech production networks. These findings support the hypothesis that the spread of neurodegeneration occurs by following specific anatomical and functional neuronal network architectures. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  18. Technology for Manufacturing Efficiency

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The Ground Processing Scheduling System (GPSS) was developed by Ames Research Center, Kennedy Space Center and divisions of the Lockheed Company to maintain the scheduling for preparing a Space Shuttle Orbiter for a mission. Red Pepper Software Company, now part of PeopleSoft, Inc., commercialized the software as their ResponseAgent product line. The software enables users to monitor manufacturing variables, report issues and develop solutions to existing problems.

  19. Not so Fast My Friend: The Rush to R and the Need for Rigorous Evaluation of Data Analysis and Software in Education

    ERIC Educational Resources Information Center

    Harwell, Michael

    2014-01-01

    Commercial data analysis software has been a fixture of quantitative analyses in education for more than three decades. Despite its apparent widespread use there is no formal evidence cataloging what software is used in educational research and educational statistics classes, by whom and for what purpose, and whether some programs should be…

  20. Current trends for customized biomedical software tools.

    PubMed

    Khan, Haseeb Ahmad

    2017-01-01

    In the past, biomedical scientists were solely dependent on expensive commercial software packages for various applications. However, the advent of user-friendly programming languages and open source platforms has revolutionized the development of simple and efficient customized software tools for solving specific biomedical problems. Many of these tools are designed and developed by biomedical scientists independently or with the support of computer experts and often made freely available for the benefit of scientific community. The current trends for customized biomedical software tools are highlighted in this short review.

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