WorldWideScience

Sample records for dynamic test system

  1. Testing relativity with solar system dynamics

    Science.gov (United States)

    Hellings, R. W.

    1984-01-01

    A major breakthrough is described in the accuracy of Solar System dynamical tests of relativistic gravity. The breakthrough was achieved by factoring in ranging data from Viking Landers 1 and 2 from the surface of Mars. Other key data sources included optical transit circle observations, lunar laser ranging, planetary radar, and spacecraft (Mariner 9 to Mars and Mariner 10 to Mercury). The Solar System model which is used to fit the data and the process by which such fits are performed are explained and results are discussed. The results are fully consistent with the predictions of General Relativity.

  2. Making System Dynamics Cool? Using Hot Testing & Teaching Cases

    NARCIS (Netherlands)

    Pruyt, E.

    2009-01-01

    This paper deals with the use of ‘hot’ real-world cases for both testing and teaching purposes such as in the Introductory System Dynamics course at Delft University of Technology in the Netherlands. The paper starts with a brief overview of the System Dynamics curriculum. Then the problem-oriented

  3. Making System Dynamics Cool IV : Teaching & Testing with Cases & Quizzes

    NARCIS (Netherlands)

    Pruyt, E.

    2012-01-01

    This follow-up paper presents cases and multiple choice questions for teaching and testing System Dynamics modeling. These cases and multiple choice questions were developed and used between January 2012 and April 2012 a large System Dynamics course (250+ 2nd year BSc and 40+ MSc students per year)

  4. Making System Dynamics Cool III : New Hot Teaching & Testing Cases

    NARCIS (Netherlands)

    Pruyt, E.

    2011-01-01

    This follow-up paper presents seven actual cases for testing and teaching System Dynamics developed and used between January 2010 and January 2011 for one of the largest System Dynamics courses (250+ students per year) at Delft University of Technology in the Netherlands. The cases presented in this

  5. A semiautomated computer-interactive dynamic impact testing system

    International Nuclear Information System (INIS)

    Alexander, D.J.; Nanstad, R.K.; Corwin, W.R.; Hutton, J.T.

    1989-01-01

    A computer-assisted semiautomated system has been developed for testing a variety of specimen types under dynamic impact conditions. The primary use of this system is for the testing of Charpy specimens. Full-, half-, and third-size specimens have been tested, both in the lab and remotely in a hot cell for irradiated specimens. Specimens are loaded into a transfer device which moves the specimen into a chamber, where a hot air gun is used to heat the specimen, or cold nitrogen gas is used for cooling, as required. The specimen is then quickly transferred from the furnace to the anvils and then broken. This system incorporates an instrumented tup to determine the change in voltage during the fracture process. These data are analyzed by the computer system after the test is complete. The voltage-time trace is recorded with a digital oscilloscope, transferred to the computer, and analyzed. The analysis program incorporates several unique features. It interacts with the operator and identifies the maximum voltage during the test, the amount of rapid fracture during the test (if any), and the end of the fracture process. The program then calculates the area to maximum voltage and the total area under the voltage-time curve. The data acquisition and analysis part of the system can also be used to conduct other dynamic testing. Dynamic tear and precracked specimens can be tested with an instrumented tup and analyzed in a similar manner. 3 refs., 7 figs

  6. Dynamic Object Oriented Requirements System (DOORS) System Test Plan

    International Nuclear Information System (INIS)

    JOHNSON, A.L.

    2000-01-01

    The U. S. Department of Energy, Office of River Protection (ORP) will use the Dynamic Object Oriented Requirements System (DOORS) as a tool to assist in identifying, capturing, and maintaining the necessary and sufficient set of requirements for accomplishing the ORP mission. By managing requirements as one integrated set, the ORP will be able to carry out its mission more efficiently and effectively. DOORS is a Commercial-Off-The-Shelf (COTS) requirements management tool. The tool has not been customized for the use of the PIO, at this time

  7. Dynamic testing of MFTF containment-vessel structural system

    International Nuclear Information System (INIS)

    Weaver, H.J.; McCallen, D.B.; Eli, M.W.

    1982-01-01

    Dynamic (modal) testing was performed on the Magnetic Fusion Test Facility (MFTF) containment vessel. The seismic design of this vessel was heavily dependent upon the value of structural damping used in the analysis. Typically for welded steel vessels, a value of 2 to 3% of critical is used. However, due to the large mass of the vessel and magnet supported inside, we felt that the interaction between the structure and its foundation would be enhanced. This would result in a larger value of damping because vibrational energy in the structure would be transferred through the foundation into the surrounding soil. The dynamic test performed on this structure (with the magnet in place) confirmed this later theory and resulted in damping values of approximately 4 to 5% for the whole body modes. This report presents a brief description of dynamic testing emphasizing the specific test procedure used on the MFTF-A system. It also presents an interpretation of the damping mechanisms observed (material and geometric) based upon the spatial characteristics of the modal parameters

  8. Isotope techniques in non-destructive testing of dynamic systems

    International Nuclear Information System (INIS)

    Singh, Gursharan; Pant, H.J.

    1996-01-01

    A few applications of gamma scanning and radiotracer techniques for Non-destructive Testing (NDT) of dynamic systems in chemical and petrochemical industries are briefly discussed in this paper. Examples of gamma scanning inspections carried out for troubleshooting of various types of columns such as vacuum, extraction, separator and rectifier, with trays and packed beds and having diameters from 1 meter to 8.4 meters are given. Radiotracer applications for Residence Time Distribution (RTD) studies on different systems like an aniline production reactor in a chemical industry and a laboratory scale solid-liquid fluidized bed column are mentioned. (author)

  9. 16 CFR 1203.16 - Dynamic strength of retention system test.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Dynamic strength of retention system test.... (2) The retention system strength test equipment shall consist of a dynamic impact apparatus that... stirrup. (2) Mark the pre-test position of the retention system, with the entire dynamic test apparatus...

  10. Making System Dynamics Cool II : New Hot Teaching and Testing Cases of Increasing Complexity

    NARCIS (Netherlands)

    Pruyt, E.

    2010-01-01

    This follow-up paper presents several actual cases for testing and teaching System Dynamics. The cases were developed between April 2009 and January 2010 for the Introductory System Dynamics courses at Delft University of Technology in the Netherlands. They can be used for teaching and testing

  11. A Dynamic Alignment System for the Final Focus Test Beam

    International Nuclear Information System (INIS)

    Ruland, R.E.; Bressler, V.E.; Fischer, G.; Plouffe, D.; SLAC

    2005-01-01

    The Final Focus Test Beam (FFTB) was conceived as a technological stepping stone on the way to the next linear collider. Nowhere is this more evident than with the alignment subsystems. Alignment tolerances for components prior to beam turn are almost an order of magnitude smaller than for previous projects at SLAC. Position monitoring systems which operate independent of the beam are employed to monitor motions of the components locally and globally with unprecedented precision. An overview of the FFTB alignment system is presented herein

  12. Testing of tunnel support: dynamic load testing of rock support containment systems (eg wire mesh).

    CSIR Research Space (South Africa)

    Ortlepp, WD

    1997-07-01

    Full Text Available The objective of this project was to determine the performance characteristics of containment elements of tunnel support in common use in South African mines under dynamic loading. The magnitude of the energy levels in this testing had...

  13. Validation of programmable industrial automation systems for safety critical applications in NPP's dynamic testing

    International Nuclear Information System (INIS)

    Haapanen, P.; Korhonen, J.

    1995-01-01

    The safety assessment of programmable automation systems can not totally be based on conventional probabilistic methods because of the difficulties in quantification of the reliability of the software as well as the hardware. Additional means shall therefore be used to gain more confidence on the system dependability. One central confidence building measure is the independent dynamic testing of the completed system. An automated test harness is needed to run the required large amount of test cases in a restricted time span. The prototype dynamic testing harness for programmable digital systems developed at the Technical Research Centre of Finland (VTT) is described in the presentation. (12 refs., 2 figs., 2 tabs.)

  14. Validation of programmable industrial automation systems for safety critical applications in NPP's; dynamic testing

    International Nuclear Information System (INIS)

    Haapanen, P.; Korhonen, J.

    1995-01-01

    The safety assessment of programmable automation systems cannot be totally be based on conventional probabilistic methods because of the difficulties in quantification of the reliability of the software as well as the hardware. Additional means shall therefore be used to gain more confidence on the system dependability. One central confidence building measure is the independent dynamic testing of the completed system. An automated test harness is needed to run the required large amount of test cases in a restricted time span. This paper describes a prototype dynamic testing harness for programmable digital systems developed at VTT. (author). 12 refs, 2 figs, 2 tabs

  15. Dynamic rock tests using split Hopkinson (Kolsky bar system – A review

    Directory of Open Access Journals (Sweden)

    Kaiwen Xia

    2015-02-01

    Full Text Available Dynamic properties of rocks are important in a variety of rock mechanics and rock engineering problems. Due to the transient nature of the loading, dynamic tests of rock materials are very different from and much more challenging than their static counterparts. Dynamic tests are usually conducted using the split Hopkinson bar or Kolsky bar systems, which include both split Hopkinson pressure bar (SHPB and split Hopkinson tension bar (SHTB systems. Significant progress has been made on the quantification of various rock dynamic properties, owing to the advances in the experimental techniques of SHPB system. This review aims to fully describe and critically assess the detailed procedures and principles of techniques for dynamic rock tests using split Hopkinson bars. The history and principles of SHPB are outlined, followed by the key loading techniques that are useful for dynamic rock tests with SHPB (i.e. pulse shaping, momentum-trap and multi-axial loading techniques. Various measurement techniques for rock tests in SHPB (i.e. X-ray micro computed tomography (CT, laser gap gauge (LGG, digital image correlation (DIC, Moiré method, caustics method, photoelastic coating method, dynamic infrared thermography are then discussed. As the main objective of the review, various dynamic measurement techniques for rocks using SHPB are described, including dynamic rock strength measurements (i.e. dynamic compression, tension, bending and shear tests, dynamic fracture measurements (i.e. dynamic imitation and propagation fracture toughness, dynamic fracture energy and fracture velocity, and dynamic techniques for studying the influences of temperature and pore water.

  16. System dynamics

    International Nuclear Information System (INIS)

    Kim, Do Hun; Mun, Tae Hun; Kim, Dong Hwan

    1999-02-01

    This book introduces systems thinking and conceptual tool and modeling tool of dynamics system such as tragedy of single thinking, accessible way of system dynamics, feedback structure and causal loop diagram analysis, basic of system dynamics modeling, causal loop diagram and system dynamics modeling, information delay modeling, discovery and application for policy, modeling of crisis of agricultural and stock breeding products, dynamic model and lesson in ecosystem, development and decadence of cites and innovation of education forward system thinking.

  17. Analysis, Test and Simulation of Landing System Touchdown Dynamics

    OpenAIRE

    Witte, L.; Buchwald, R.; Schröder, S.; van Zoest, Tim

    2013-01-01

    Future exploration missions pose demanding requirements towards the access by vehicles to scientifically interesting sites on planetary surfaces. These stem particularly from the need of more flexibility in site selection, improved payload to vehicle mass ratios and higher mission success probabilities. The Landing Technology group of the DLR Institute of Space Systems is focusing on the development and verification of experimental and analytical methods for the investigation of the touchd...

  18. The ground testing of a 2 kWe solar dynamic space power system

    International Nuclear Information System (INIS)

    Calogeras, J.E.

    1992-01-01

    Over the past 25 years Space Solar Dynamic component development has advanced to the point where it is considered a leading candidate power source technology for the evolutionary phases of the Space Station Freedom (SSF) program. Selection of SD power was based on studies and analyses which indicated significant savings in life cycle costs, launch mass and EVA requirements were possible when the system is compared to more conventional photovoltaic/battery power systems. Issues associated with micro-gravity operation such as the behavior of the thermal energy storage materials are being addressed in other programs. This paper reports that a ground test of a 2 kWe solar dynamic system is being planned by the NASA Office of Aeronautics and Space Technology to address the integration issues. The test will be scalable up to 25 kWe, will be flight configured and will incorporate relevant features of the SSF Solar Dynamic Power Module design

  19. Computer aided instrumented Charpy test applied dynamic fracture toughness evaluation system

    International Nuclear Information System (INIS)

    Kobayashi, Toshiro; Niinomi, Mitsuo

    1986-01-01

    Micro computer aided data treatment system and personal computer aided data analysis system were applied to the traditional instrumented Charpy impact test system. The analysis of Charpy absorbed energy (E i , E p , E t ) and load (P y , P m ), and the evaluation of dynamic toughness through whole fracture process, i.e. J Id , J R curve and T mat was examined using newly developed computer aided instrumented Charpy impact test system. E i , E p , E t , P y and P m were effectively analyzed using moving average method and printed out automatically by micro computer aided data treatment system. J Id , J R curve and T mat could be measured by stop block test method. Then, J Id , J R curve and T mat were effectively estimated using compliance changing rate method and key curve method on the load-load point displacement curve of single fatigue cracked specimen by personal computer aided data analysis system. (author)

  20. Dynamical systems

    CERN Document Server

    Sternberg, Shlomo

    2010-01-01

    Celebrated mathematician Shlomo Sternberg, a pioneer in the field of dynamical systems, created this modern one-semester introduction to the subject for his classes at Harvard University. Its wide-ranging treatment covers one-dimensional dynamics, differential equations, random walks, iterated function systems, symbolic dynamics, and Markov chains. Supplementary materials offer a variety of online components, including PowerPoint lecture slides for professors and MATLAB exercises.""Even though there are many dynamical systems books on the market, this book is bound to become a classic. The the

  1. Standard practice for verification of constant amplitude dynamic forces in an axial fatigue testing system

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This practice covers procedures for the dynamic verification of cyclic force amplitude control or measurement accuracy during constant amplitude testing in an axial fatigue testing system. It is based on the premise that force verification can be done with the use of a strain gaged elastic element. Use of this practice gives assurance that the accuracies of forces applied by the machine or dynamic force readings from the test machine, at the time of the test, after any user applied correction factors, fall within the limits recommended in Section 9. It does not address static accuracy which must first be addressed using Practices E 4 or equivalent. 1.2 Verification is specific to a particular test machine configuration and specimen. This standard is recommended to be used for each configuration of testing machine and specimen. Where dynamic correction factors are to be applied to test machine force readings in order to meet the accuracy recommended in Section 9, the verification is also specific to the c...

  2. Experimental Testing Procedures and Dynamic Model Validation for Vanadium Redox Flow Battery Storage System

    DEFF Research Database (Denmark)

    Baccino, Francesco; Marinelli, Mattia; Nørgård, Per Bromand

    2013-01-01

    The paper aims at characterizing the electrochemical and thermal parameters of a 15 kW/320 kWh vanadium redox flow battery (VRB) installed in the SYSLAB test facility of the DTU Risø Campus and experimentally validating the proposed dynamic model realized in Matlab-Simulink. The adopted testing...... efficiency of the battery system. The test procedure has general validity and could also be used for other storage technologies. The storage model proposed and described is suitable for electrical studies and can represent a general model in terms of validity. Finally, the model simulation outputs...

  3. Six-Degree-of-Freedom Dynamic Test System (SDTS) User Test Planning Guide

    Science.gov (United States)

    Stokes, LeBarian

    2012-01-01

    Test process, milestones and inputs are unknowns to first-time users of the SDTS. The User Test Planning Guide aids in establishing expectations for both NASA and non- NASA facility customers. The potential audience for this guide includes both internal and commercial spaceflight hardware/software developers. It is intended to assist their test engineering personnel in test planning and execution. Material covered includes a roadmap of the test process, roles and responsibilities of facility and user, major milestones, facility capabilities, and inputs required by the facility. Samples of deliverables, test article interfaces, and inputs necessary to define test scope, cost, and schedule are included as an appendix to the guide.

  4. The behaviour of a vehicle’s suspension system on dynamic testing conditions

    Science.gov (United States)

    Mihon, L.; Lontiş, N.; Deac, S.

    2018-01-01

    The paper presents a car suspension’s behaviour on dynamic testing conditions through theoretical and mathematical simulation on specific model, on the single traction wheel, according to the real vehicle and by experiment on the test bench by reproducing the road’s geometry and vehicle’s speed and measuring the acceleration and damping response of the suspension system on that wheel. There are taking in consideration also the geometry and properties of the tyre-wheel model and physical wheel’s properties. The results are important due to the suspension’s model properties which allows to extend the theory and applications to the whole vehicle for improving the vehicle’s dynamics.

  5. Incorporating Vibration Test Results for the Advanced Stirling Convertor into the System Dynamic Model

    Science.gov (United States)

    Meer, David W.; Lewandowski, Edward J.

    2010-01-01

    The U.S. Department of Energy (DOE), Lockheed Martin Corporation (LM), and NASA Glenn Research Center (GRC) have been developing the Advanced Stirling Radioisotope Generator (ASRG) for use as a power system for space science missions. As part of the extended operation testing of this power system, the Advanced Stirling Convertors (ASC) at NASA GRC undergo a vibration test sequence intended to simulate the vibration history that an ASC would experience when used in an ASRG for a space mission. During these tests, a data system collects several performance-related parameters from the convertor under test for health monitoring and analysis. Recently, an additional sensor recorded the slip table position during vibration testing to qualification level. The System Dynamic Model (SDM) integrates Stirling cycle thermodynamics, heat flow, mechanical mass, spring, damper systems, and electrical characteristics of the linear alternator and controller. This Paper presents a comparison of the performance of the ASC when exposed to vibration to that predicted by the SDM when exposed to the same vibration.

  6. System Dynamics

    Science.gov (United States)

    Morecroft, John

    System dynamics is an approach for thinking about and simulating situations and organisations of all kinds and sizes by visualising how the elements fit together, interact and change over time. This chapter, written by John Morecroft, describes modern system dynamics which retains the fundamentals developed in the 1950s by Jay W. Forrester of the MIT Sloan School of Management. It looks at feedback loops and time delays that affect system behaviour in a non-linear way, and illustrates how dynamic behaviour depends upon feedback loop structures. It also recognises improvements as part of the ongoing process of managing a situation in order to achieve goals. Significantly it recognises the importance of context, and practitioner skills. Feedback systems thinking views problems and solutions as being intertwined. The main concepts and tools: feedback structure and behaviour, causal loop diagrams, dynamics, are practically illustrated in a wide variety of contexts from a hot water shower through to a symphony orchestra and the practical application of the approach is described through several real examples of its use for strategic planning and evaluation.

  7. Initial virtual flight test for a dynamically similar aircraft model with control augmentation system

    Directory of Open Access Journals (Sweden)

    Linliang Guo

    2017-04-01

    Full Text Available To satisfy the validation requirements of flight control law for advanced aircraft, a wind tunnel based virtual flight testing has been implemented in a low speed wind tunnel. A 3-degree-of-freedom gimbal, ventrally installed in the model, was used in conjunction with an actively controlled dynamically similar model of aircraft, which was equipped with the inertial measurement unit, attitude and heading reference system, embedded computer and servo-actuators. The model, which could be rotated around its center of gravity freely by the aerodynamic moments, together with the flow field, operator and real time control system made up the closed-loop testing circuit. The model is statically unstable in longitudinal direction, and it can fly stably in wind tunnel with the function of control augmentation of the flight control laws. The experimental results indicate that the model responds well to the operator’s instructions. The response of the model in the tests shows reasonable agreement with the simulation results. The difference of response of angle of attack is less than 0.5°. The effect of stability augmentation and attitude control law was validated in the test, meanwhile the feasibility of virtual flight test technique treated as preliminary evaluation tool for advanced flight vehicle configuration research was also verified.

  8. Dynamical systems

    CERN Document Server

    Birkhoff, George D

    1927-01-01

    His research in dynamics constitutes the middle period of Birkhoff's scientific career, that of maturity and greatest power. -Yearbook of the American Philosophical Society The author's great book€¦is well known to all, and the diverse active modern developments in mathematics which have been inspired by this volume bear the most eloquent testimony to its quality and influence. -Zentralblatt MATH In 1927, G. D. Birkhoff wrote a remarkable treatise on the theory of dynamical systems that would inspire many later mathematicians to do great work. To a large extent, Birkhoff was writing about his o

  9. Dynamic testing and qualification

    International Nuclear Information System (INIS)

    Kleine Tebbe, A.; Schmidt, G.; Theymann, W.

    1990-01-01

    The core structure of an HTR-plant consists of the side reflector, the bottom reflector, the top reflector and the pebble bed of spherical fuel elements. Dynamically this system is a many-body structure with non-linear force-deformation couplings. The integrity of the system under seismic loads is given by radially orientated spring packs. These spring packs must be stiff against earthquake loads, but must allow radial thermal movements. To verify the seismic safety of the system, scaled-down models were tested. The results of these tests were compared with those of analytical methods. The good-natured behaviour of the pebble-bed under seismic loads has been confirmed. Due to the granular structure of the non-regular packed pebble-bed, high damping occurs during seismic excitations. With increasing depth the damping ratio decreases because of restriction of movement. We are able to describe the seismic behaviour of the pebble-bed analytically. The one- and two-dimensional test configurations of the top reflector were used to analyse resonance and lumping effects. The experimental results were verified by the computer codes CRUNCH-1D AND CRUNCH-2D. The experimental investigations of the side reflector are underway. The results show a non-critical behaviour under horizontal excitations. Small rigid-body motions of single blocks are detected, but they do not cause any global ovalisations of the complete ring structure. Finite element calculations with contact and friction between the blocks show a close agreement with the experimental results. Seismic qualification of ground mounted electrical equipment is usually performed on the basis of codes like IEEE, IEC, KTA, etc. These standards give different possibilities of the excitation mode: sinusoidal excitation in every natural frequency (continuous or sine beat) or time history excitation which covers a prescribed required response spectrum. Recently performed tests are compared regarding the usefulness and severity

  10. Real-time numerical evaluation of dynamic tests with sudden closing of valves in piping systems

    International Nuclear Information System (INIS)

    Geidel, W.; Leimbach, K.R.

    1979-01-01

    The sudden closing of a valve in a piping system causes a build-up of pressure which, in turn, causes severe vibrations of the structural system. The licensing procedure calls for on-site tests to determine the dynamic effects of such closing of valves, and to check the stresses and displacements against the allowable ones. The measurements include time histories of displacements, accelerations and internal pressure. The computer program KWUROHR for the static and dynamic analysis of piping systems has been used by KWU and several subcontractors during the past four vears. This program has been extended by adding a subroutine package which computes time histories of displacements, accelerations and stresses resulting from the input of measured time histories of internal pressures at selected locations. The computer algorithm establishes the topological connectivity between the internal pressure measuring locations, to set up a logic for linear pressure interpolation between these points and pressure steps at reducers and valves. A minimum number of input points is required to give realistic results. (orig.)

  11. An impact test system design and its applications to dynamic buckling of a spacer grid assembly

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Sheng, E-mail: liusheng_05@126.com; Fan, Chenguang; Yang, Yiren

    2016-11-15

    This study is aimed at investigating the dynamic buckling load, dynamic stiffness, damping and buckling characteristics of the spacer grid assembly (SGA). A pendulum impact test system is designed to experiment the buckling of SGAs. Three criterions are discussed and compared to determine the buckling loads of SGAs: B-R criterion, energy criterion and extreme value criterion. Two approaches are applied to calculate the dynamic stiffness of SGAs: One method is natural period method based on the hypothesis of harmonic motion of the pendulum whose period is approximated because of the passivation and tailing of the impact force time history; and the other is energy method based on the conservation of mechanical energy. The equivalent viscous damping is defined as the resultant cause of dissipation and is obtained by the energy principle. The impact force time history loses its approximate symmetry after buckling occurs. The impact force and displacement reach their maxima almost at the same time at pre-buckling states but not post-buckling states. Vertical straps in SGA are found to be transversely shared by horizontal straps at the buckling position. The buckling of SGA results from the lack of strength of complete structure; and the strength of material has no effects on the buckling.

  12. Comparison of a nonlinear dynamic model of a piping system to test data

    International Nuclear Information System (INIS)

    Blakely, K.D.; Howard, G.E.; Walton, W.B.; Johnson, B.A.; Chitty, D.E.

    1983-01-01

    Response of a nonlinear finite element model of the Heissdampfreaktor recirculation piping loop (URL) was compared to measured data, representing the physical benchmarking of a nonlinear model. Analysis-test comparisons of piping response are presented for snapback tests that induced extreme nonlinear behavior of the URL system. Nonlinearities in the system are due to twelve swaybraces (pipe supports) that possessed nonlinear force-deflection characteristics. These nonlinearities distorted system damping estimates made by using the half-power bandwidth method on Fourier transforms of measured accelerations, with the severity of distortion increasing with increasing degree of nonlinearity. Time domain methods, which are not so severely affected by the presence of nonlinearities, were used to compute system damping ratios. Nonlinear dynamic analyses were accurately and efficiently performed using the pseudo-force technique and the finite element program MSC/NASTRAN. Measured damping was incorporated into the model for snapback simulations. Acceleration time histories, acceleration Fourier transforms, and swaybrace force time histories of the nonlinear model, plus several linear models, were compared to test measurements. The nonlinear model predicted three-fourths of the measured peak accelerations to within 50%, half of the accelerations to within 25%, and one-fifth of the accelerations to within 10%. This nonlinear model predicted accelerations (in the time and frequency domains) and swaybrace forces much better than did any of the linear models, demonstrating the increased accuracy resulting from properly simulating nonlinear support behavior. In addition, earthquake response comparisons were made between the experimentally validated nonlinear model and a linear model. Significantly lower element stresses were predicted for the nonlinear model, indicating the potential usefulness of nonlinear simulations in piping design assessments. (orig.)

  13. Dynamic testing of cable structures

    Directory of Open Access Journals (Sweden)

    Caetano Elsa

    2015-01-01

    Full Text Available The paper discusses the role of dynamic testing in the study of cable structures. In this context, the identification of cable force based on vibration measurements is discussed. Vibration and damping assessment are then introduced as the focus of dynamic monitoring systems, and particular aspects of the structural behaviour under environmental loads are analysed. Diverse application results are presented to support the discussion centred on cable-stayed bridges, roof structures, a guyed mast and a transmission line.

  14. Dynamic simulations for preparing the acceptance test of JT-60SA cryogenic system

    Science.gov (United States)

    Cirillo, R.; Hoa, C.; Michel, F.; Poncet, J. M.; Rousset, B.

    2016-12-01

    Power generation in the future could be provided by thermo-nuclear fusion reactors like tokamaks. There inside, the fusion reaction takes place thanks to the generation of plasmas at hundreds of millions of degrees that must be confined magnetically with superconductive coils, cooled down to around 4.5 K. Within this frame, an experimental tokamak device, JT-60SA is currently under construction in Naka (Japan). The plasma works cyclically and the coil system is subject to pulsed heat loads. In order to size the refrigerator close to the average power and hence optimizing investment and operational costs, measures have to be taken to smooth the heat load. Here we present a dynamic model of the JT-60SA's Auxiliary Cold box (ACB) for preparing the acceptance tests of the refrigeration system planned in 2016 in Naka. The aim of this study is to simulate the pulsed load scenarios using different process controls. All the simulations have been performed with EcosimPro® and the associated cryogenic library: CRYOLIB.

  15. AirSTAR: A UAV Platform for Flight Dynamics and Control System Testing

    Science.gov (United States)

    Jordan, Thomas L.; Foster, John V.; Bailey, Roger M.; Belcastro, Christine M.

    2006-01-01

    As part of the NASA Aviation Safety Program at Langley Research Center, a dynamically scaled unmanned aerial vehicle (UAV) and associated ground based control system are being developed to investigate dynamics modeling and control of large transport vehicles in upset conditions. The UAV is a 5.5% (seven foot wingspan), twin turbine, generic transport aircraft with a sophisticated instrumentation and telemetry package. A ground based, real-time control system is located inside an operations vehicle for the research pilot and associated support personnel. The telemetry system supports over 70 channels of data plus video for the downlink and 30 channels for the control uplink. Data rates are in excess of 200 Hz. Dynamic scaling of the UAV, which includes dimensional, weight, inertial, actuation, and control system scaling, is required so that the sub-scale vehicle will realistically simulate the flight characteristics of the full-scale aircraft. This testbed will be utilized to validate modeling methods, flight dynamics characteristics, and control system designs for large transport aircraft, with the end goal being the development of technologies to reduce the fatal accident rate due to loss-of-control.

  16. Structural Dynamic Assessment of the GN2 Piping System for NASA's New and Powerful Reverberant Acoustic Test Facility

    Science.gov (United States)

    McNelis, Mark E.; Staab, Lucas D.; Akers, James C.; Hughes, WIlliam O.; Chang, Li, C.; Hozman, Aron D.; Henry, Michael W.

    2012-01-01

    The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) has led the design and build of the new world-class vibroacoustic test capabilities at the NASA GRC's Plum Brook Station in Sandusky, Ohio, USA from 2007-2011. SAIC-Benham has completed construction of a new reverberant acoustic test facility to support the future testing needs of NASA's space exploration program and commercial customers. The large Reverberant Acoustic Test Facility (RATF) is approximately 101,000 cu ft in volume and was designed to operate at a maximum empty chamber acoustic overall sound pressure level (OASPL) of 163 dB. This combination of size and acoustic power is unprecedented amongst the world's known active reverberant acoustic test facilities. Initial checkout acoustic testing was performed on March 2011 by SAIC-Benham at test levels up to 161 dB OASPL. During testing, several branches of the gaseous nitrogen (GN2) piping system, which supply the fluid to the noise generating acoustic modulators, failed at their "t-junctions" connecting the 12 inch supply line to their respective 4 inch branch lines. The problem was initially detected when the oxygen sensors in the horn room indicated a lower than expected oxygen level from which was inferred GN2 leaks in the piping system. In subsequent follow up inspections, cracks were identified in the failed "t-junction" connections through non-destructive evaluation testing . Through structural dynamic modeling of the piping system, the root cause of the "t-junction" connection failures was determined. The structural dynamic assessment identified several possible corrective design improvements to the horn room piping system. The effectiveness of the chosen design repairs were subsequently evaluated in September 2011 during acoustic verification testing to 161 dB OASPL.

  17. Dynamic analysis and vibration testing of CFRP drive-line system used in heavy-duty machine tool

    Directory of Open Access Journals (Sweden)

    Mo Yang

    2018-03-01

    Full Text Available Low critical rotary speed and large vibration in the metal drive-line system of heavy-duty machine tool affect the machining precision seriously. Replacing metal drive-line with the CFRP drive-line can effectively solve this problem. Based on the composite laminated theory and the transfer matrix method (TMM, this paper puts forward a modified TMM to analyze dynamic characteristics of CFRP drive-line system. With this modified TMM, the CFRP drive-line of a heavy vertical miller is analyzed. And the finite element modal analysis model of the shafting is established. The results of the modified TMM and finite element analysis (FEA show that the modified TMM can effectively predict the critical rotary speed of CFRP drive-line. And the critical rotary speed of CFRP drive-line is 20% higher than that of the original metal drive-line. Then, the vibration of the CFRP and the metal drive-line were tested. The test results show that application of the CFRP drive shaft in the drive-line can effectively reduce the vibration of the heavy-duty machine tool. Keywords: CFRP drive-line system, Dynamic behavior, Transfer matrix, Vibration measurement

  18. Microclimate measuring and fluid‑dynamic simulation in an industrial broiler house: testing of an experimental ventilation system.

    Science.gov (United States)

    Bianchi, Biagio; Giametta, Ferruccio; La Fianza, Giovanna; Gentile, Andrea; Catalano, Pasquale

    2015-01-01

    The environment in the broiler house is a combination of physical and biological factors generating a complex dynamic system of interactions between birds, husbandry system, light, temperature, and the aerial environment. Ventilation plays a key role in this scenario. It is pivotal to remove carbon dioxide and water vapor from the air of the hen house. Adequate ventilation rates provide the most effective method of controlling temperature within the hen house. They allow for controlling the relative humidity and can play a key role in alleviating the negative effects of high stocking density and of wet litter. In the present study the results of experimental tests performed in a breeding broiler farm are shown. In particular the efficiency of a semi transversal ventilation system was studied against the use of a pure transversal one. In order to verify the efficiency of the systems, fluid dynamic simulations were carried out using the software Comsol multiphysics. The results of this study show that a correct architectural and structural design of the building must be supported by a design of the ventilation system able to maintain the environmental parameters within the limits of the thermo‑neutral and welfare conditions and to achieve the highest levels of productivity.

  19. Emergence in Dynamical Systems

    Directory of Open Access Journals (Sweden)

    John Collier

    2013-12-01

    Full Text Available Emergence is a term used in many contexts in current science; it has become fashionable. It has a traditional usage in philosophy that started in 1875 and was expanded by J. S. Mill (earlier, under a different term and C. D. Broad. It is this form of emergence that I am concerned with here. I distinguish it from uses like ‘computational emergence,’ which can be reduced to combinations of program steps, or its application to merely surprising new features that appear in complex combinations of parts. I will be concerned specifically with ontological emergence that has the logical properties required by Mill and Broad (though there might be some quibbling about the details of their views. I restrict myself to dynamical systems that are embodied in processes. Everything that we can interact with through sensation or action is either dynamical or can be understood in dynamical terms, so this covers all comprehensible forms of emergence in the strong (nonreducible sense I use. I will give general dynamical conditions that underlie the logical conditions traditionally assigned to emergence in nature.The advantage of this is that, though we cannot test logical conditions directly, we can test dynamical conditions. This gives us an empirical and realistic form of emergence, contrary those who say it is a matter of perspective.

  20. Dynamics test on structures

    International Nuclear Information System (INIS)

    De Canio, G.; Ranieri, N.

    2009-01-01

    Shake table tests allow to assess the effectiveness of technologies for structures protection from natural events such as earthquakes. The article summarizes the remarkable results of the most significant projects. [it

  1. What Sensing Tells Us: Towards a Formal Theory of Testing for Dynamical Systems

    Science.gov (United States)

    McIlraith, Sheila; Scherl, Richard

    2005-01-01

    Just as actions can have indirect effects on the state of the world, so too can sensing actions have indirect effects on an agent's state of knowledge. In this paper, we investigate "what sensing actions tell us", i.e., what an agent comes to know indirectly from the outcome of a sensing action, given knowledge of its actions and state constraints that hold in the world. To this end, we propose a formalization of the notion of testing within a dialect of the situation calculus that includes knowledge and sensing actions. Realizing this formalization requires addressing the ramification problem for sensing actions. We formalize simple tests as sensing actions. Complex tests are expressed in the logic programming language Golog. We examine what it means to perform a test, and how the outcome of a test affects an agent's state of knowledge. Finally, we propose automated reasoning techniques for test generation and complex-test verification, under certain restrictions. The work presented in this paper is relevant to a number of application domains including diagnostic problem solving, natural language understanding, plan recognition, and active vision.

  2. Dynamics of test black holes

    International Nuclear Information System (INIS)

    Epikhin, E.N.

    1981-01-01

    A concept of a test object is introduced. This definition includes also small black holes. Reduced approximation of testing permits to unambiguously introduce a concept of background space-time. Dynamic values for test objects are introduced by means of the Noether theorem which gave the possibility to covariantly generalize pseudotensor of the Papapetru energy-momentum for the case of curved background space-time. Additional use of radiation approximation and the accountancy of the zero and first momenta of dynamic values lead to the conclusion that motion of the test object (including small black holes) is subordinated to the Matthiessen-Papapetru equations. The above results are testified to the accountancy of a proper gravitational field of the test object in integrated dynamic values [ru

  3. Virtual Drive Testing of Adaptive Antenna Systems in Dynamic Propagation Scenarios for Vehicle Communications

    DEFF Research Database (Denmark)

    Fan, Wei; Hentilä, Lassi; Zhang, Fengchun

    2018-01-01

    Virtual drive testing (VDT) has gained great interest from both industry and academia, owing to its promise to replay field trials in a controllable laboratory condition. VDT is especially appealing for vehicle communication scenarios, where actual field trials can be difficult to carry out...

  4. Spaces of Dynamical Systems

    CERN Document Server

    Pilyugin, Sergei Yu

    2012-01-01

    Dynamical systems are abundant in theoretical physics and engineering. Their understanding, with sufficient mathematical rigor, is vital to solving many problems. This work conveys the modern theory of dynamical systems in a didactically developed fashion.In addition to topological dynamics, structural stability and chaotic dynamics, also generic properties and pseudotrajectories are covered, as well as nonlinearity. The author is an experienced book writer and his work is based on years of teaching.

  5. AGARD Flight Test Techniques Series. Volume 2. Identification of Dynamic Systems

    Science.gov (United States)

    1985-01-01

    should not depend upon it to solve the problem autonomously. The analyst’s strong point is in formulating the problem; the computer’s strength is in...of derivation for the output-error method is to reduce the problem to the static form of Chapter 5. We will see that the dinamic system make- the

  6. Dynamical Systems Conference

    CERN Document Server

    Gils, S; Hoveijn, I; Takens, F; Nonlinear Dynamical Systems and Chaos

    1996-01-01

    Symmetries in dynamical systems, "KAM theory and other perturbation theories", "Infinite dimensional systems", "Time series analysis" and "Numerical continuation and bifurcation analysis" were the main topics of the December 1995 Dynamical Systems Conference held in Groningen in honour of Johann Bernoulli. They now form the core of this work which seeks to present the state of the art in various branches of the theory of dynamical systems. A number of articles have a survey character whereas others deal with recent results in current research. It contains interesting material for all members of the dynamical systems community, ranging from geometric and analytic aspects from a mathematical point of view to applications in various sciences.

  7. Dynamic Response Testing in an Electrically Heated Reactor Test Facility

    Science.gov (United States)

    Bragg-Sitton, Shannon M.; Morton, T. J.

    2006-01-01

    Non-nuclear testing can be a valuable tool in development of a space nuclear power or propulsion system. In a non-nuclear test bed, electric heaters are used to simulate the heat from nuclear fuel. Standard testing allows one to fully assess thermal, heat transfer, and stress related attributes of a given system, but fails to demonstrate the dynamic response that would be present in an integrated, fueled reactor system. The integration of thermal hydraulic hardware tests with simulated neutronic response provides a bridge between electrically heated testing and full nuclear testing. By implementing a neutronic response model to simulate the dynamic response that would be expected in a fueled reactor system, one can better understand system integration issues, characterize integrated system response times and response characteristics, and assess potential design improvements at a relatively small fiscal investment. Initial system dynamic response testing was demonstrated on the integrated SAFE-100a heat pipe cooled, electrically heated reactor and heat exchanger hardware, utilizing a one-group solution to the point kinetics equations to simulate the expected neutronic response of the system (Bragg-Sitton, 2005). The current paper applies the same testing methodology to a direct drive gas cooled reactor system, demonstrating the applicability of the testing methodology to any reactor type and demonstrating the variation in system response characteristics in different reactor concepts. In each testing application, core power transients were controlled by a point kinetics model with reactivity feedback based on core average temperature; the neutron generation time and the temperature feedback coefficient are provided as model inputs. Although both system designs utilize a fast spectrum reactor, the method of cooling the reactor differs significantly, leading to a variable system response that can be demonstrated and assessed in a non-nuclear test facility.

  8. Dynamic analysis and vibration testing of CFRP drive-line system used in heavy-duty machine tool

    Science.gov (United States)

    Yang, Mo; Gui, Lin; Hu, Yefa; Ding, Guoping; Song, Chunsheng

    2018-03-01

    Low critical rotary speed and large vibration in the metal drive-line system of heavy-duty machine tool affect the machining precision seriously. Replacing metal drive-line with the CFRP drive-line can effectively solve this problem. Based on the composite laminated theory and the transfer matrix method (TMM), this paper puts forward a modified TMM to analyze dynamic characteristics of CFRP drive-line system. With this modified TMM, the CFRP drive-line of a heavy vertical miller is analyzed. And the finite element modal analysis model of the shafting is established. The results of the modified TMM and finite element analysis (FEA) show that the modified TMM can effectively predict the critical rotary speed of CFRP drive-line. And the critical rotary speed of CFRP drive-line is 20% higher than that of the original metal drive-line. Then, the vibration of the CFRP and the metal drive-line were tested. The test results show that application of the CFRP drive shaft in the drive-line can effectively reduce the vibration of the heavy-duty machine tool.

  9. NASA Langley's AirSTAR Testbed: A Subscale Flight Test Capability for Flight Dynamics and Control System Experiments

    Science.gov (United States)

    Jordan, Thomas L.; Bailey, Roger M.

    2008-01-01

    As part of the Airborne Subscale Transport Aircraft Research (AirSTAR) project, NASA Langley Research Center (LaRC) has developed a subscaled flying testbed in order to conduct research experiments in support of the goals of NASA s Aviation Safety Program. This research capability consists of three distinct components. The first of these is the research aircraft, of which there are several in the AirSTAR stable. These aircraft range from a dynamically-scaled, twin turbine vehicle to a propeller driven, off-the-shelf airframe. Each of these airframes carves out its own niche in the research test program. All of the airplanes have sophisticated on-board data acquisition and actuation systems, recording, telemetering, processing, and/or receiving data from research control systems. The second piece of the testbed is the ground facilities, which encompass the hardware and software infrastructure necessary to provide comprehensive support services for conducting flight research using the subscale aircraft, including: subsystem development, integrated testing, remote piloting of the subscale aircraft, telemetry processing, experimental flight control law implementation and evaluation, flight simulation, data recording/archiving, and communications. The ground facilities are comprised of two major components: (1) The Base Research Station (BRS), a LaRC laboratory facility for system development, testing and data analysis, and (2) The Mobile Operations Station (MOS), a self-contained, motorized vehicle serving as a mobile research command/operations center, functionally equivalent to the BRS, capable of deployment to remote sites for supporting flight tests. The third piece of the testbed is the test facility itself. Research flights carried out by the AirSTAR team are conducted at NASA Wallops Flight Facility (WFF) on the Eastern Shore of Virginia. The UAV Island runway is a 50 x 1500 paved runway that lies within restricted airspace at Wallops Flight Facility. The

  10. Dynamic Systems and Control Engineering

    International Nuclear Information System (INIS)

    Kim, Jong Seok

    1994-02-01

    This book deals with introduction of dynamic system and control engineering, frequency domain modeling of dynamic system, temporal modeling of dynamic system, typical dynamic system and automatic control device, performance and stability of control system, root locus analysis, analysis of frequency domain dynamic system, design of frequency domain dynamic system, design and analysis of space, space of control system and digital control system such as control system design of direct digital and digitalization of consecutive control system.

  11. Dynamic Systems and Control Engineering

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Seok

    1994-02-15

    This book deals with introduction of dynamic system and control engineering, frequency domain modeling of dynamic system, temporal modeling of dynamic system, typical dynamic system and automatic control device, performance and stability of control system, root locus analysis, analysis of frequency domain dynamic system, design of frequency domain dynamic system, design and analysis of space, space of control system and digital control system such as control system design of direct digital and digitalization of consecutive control system.

  12. Static and dynamic analyses on the MFTF [Mirror Fusion Test Facility]-B Axicell Vacuum Vessel System: Final report

    International Nuclear Information System (INIS)

    Ng, D.S.

    1986-09-01

    The Mirror Fusion Test Facility (MFTF-B) at Lawrence Livermore National Laboratory (LLNL) is a large-scale, tandem-mirror-fusion experiment. MFTF-B comprises many highly interconnected systems, including a magnet array and a vacuum vessel. The vessel, which houses the magnet array, is supported by reinforced concrete piers and steel frames resting on an array of foundations and surrounded by a 7-ft-thick concrete shielding vault. The Pittsburgh-Des Moines (PDM) Corporation, which was awarded the contract to design and construct the vessel, carried out fixed-base static and dynamic analyses of a finite-element model of the axicell vessel and magnet systems, including the simulation of various loading conditions and three postulated earthquake excitations. Meanwhile, LLNL monitored PDM's analyses with modeling studies of its own, and independently evaluated the structural responses of the vessel in order to define design criteria for the interface members and other project equipment. The assumptions underlying the finite-element model and the behavior of the axicell vessel are described in detail in this report, with particular emphasis placed on comparing the LLNL and PDM studies and on analyzing the fixed-base behavior with the soil-structure interaction, which occurs between the vessel and the massive concrete vault wall during a postulated seismic event. The structural members that proved sensitive to the soil effect are also reevaluated

  13. Shaking table test and dynamic response analysis of 3-D component base isolation system using multi-layer rubber bearings and coil springs

    Energy Technology Data Exchange (ETDEWEB)

    Tsutsumi, Hideaki; Yamada, Hiroyuki; Ebisawa, Katsumi; Shibata, Katsuyuki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Fujimoto, Shigeru [Toshiba Corp., Tokyo (Japan)

    2001-06-01

    Introduction of the base isolation technique into the seismic design of nuclear power plant components as well as buildings has been expected as one of the effective countermeasure to reduce the seismic force applied to components. A research program on the base isolation of nuclear components has been carried out at the Japan Atomic Energy Research Institute (JAERI) since 1991. A methodology and a computer code (EBISA: Equipment Base Isolation System Analysis) for evaluating the failure frequency of the nuclear component with the base isolation were developed. In addition, a test program, which is concerned with the above development, aiming at improvement of failure frequency analysis models in the code has been conducted since 1996 to investigate the dynamic behavior and to verify the effectiveness of component base isolation systems. Two base isolation test systems with different characteristics were fabricated and static and dynamic characteristics were measured by static loading and free vibration tests. One which consists of ball bearings and air springs was installed on the test bed to observe the dynamic response under natural earthquake motion. The effect of base isolation system has been observed under several earthquakes. Three-dimensional response and effect of base isolation of another system using multi-layer-rubber-bearings and coil springs has been investigated under various large earthquake motions by shaking table test. This report describes the results of the shaking table tests and dynamic response analysis. (author)

  14. Stability of dynamical systems

    CERN Document Server

    Liao, Xiaoxin; Yu, P 0

    2007-01-01

    The main purpose of developing stability theory is to examine dynamic responses of a system to disturbances as the time approaches infinity. It has been and still is the object of intense investigations due to its intrinsic interest and its relevance to all practical systems in engineering, finance, natural science and social science. This monograph provides some state-of-the-art expositions of major advances in fundamental stability theories and methods for dynamic systems of ODE and DDE types and in limit cycle, normal form and Hopf bifurcation control of nonlinear dynamic systems.ʺ Presents

  15. Dynamics of unstable systems

    International Nuclear Information System (INIS)

    Posch, H.A.; Narnhofer, H.; Thirring, W.

    1990-01-01

    We study the dynamics of classical particles interacting with attractive Gaussian potentials. This system is thermodynamically not stable and exhibits negative specific heat. The results of the computer simulation of the dynamics are discussed in comparison with various theories. In particular, we find that the condensed phase is a stationary solution of the Vlasov equation, but the Vlasov dynamics cannot describe the collapse. 14 refs., 1 tab., 11 figs. (Authors)

  16. Functional System Dynamics

    OpenAIRE

    Ligterink, N.E.

    2007-01-01

    Functional system dynamics is the analysis, modelling, and simulation of continuous systems usually described by partial differential equations. From the infinite degrees of freedom of such systems only a finite number of relevant variables have to be chosen for a practical model description. The proper input and output of the system are an important part of the relevant variables.

  17. Shadowing in dynamical systems

    CERN Document Server

    Pilyugin, Sergei Yu

    1999-01-01

    This book is an introduction to the theory of shadowing of approximate trajectories in dynamical systems by exact ones. This is the first book completely devoted to the theory of shadowing. It shows the importance of shadowing theory for both the qualitative theory of dynamical systems and the theory of numerical methods. Shadowing Methods allow us to estimate differences between exact and approximate solutions on infinite time intervals and to understand the influence of error terms. The book is intended for specialists in dynamical systems, for researchers and graduate students in the theory of numerical methods.

  18. Invitation to dynamical systems

    CERN Document Server

    Scheinerman, Edward R

    2012-01-01

    This text is designed for those who wish to study mathematics beyond linear algebra but are unready for abstract material. Rather than a theorem-proof-corollary exposition, it stresses geometry, intuition, and dynamical systems. 1996 edition.

  19. Functional System Dynamics

    NARCIS (Netherlands)

    Ligterink, N.E.

    2007-01-01

    Functional system dynamics is the analysis, modelling, and simulation of continuous systems usually described by partial differential equations. From the infinite degrees of freedom of such systems only a finite number of relevant variables have to be chosen for a practical model description. The

  20. Neurotoxic impact of mercury on the central nervous system evaluated by neuropsychological tests and on the autonomic nervous system evaluated by dynamic pupillometry.

    Science.gov (United States)

    Milioni, Ana Luiza V; Nagy, Balázs V; Moura, Ana Laura A; Zachi, Elaine C; Barboni, Mirella T S; Ventura, Dora F

    2017-03-01

    Mercury vapor is highly toxic to the human body. The present study aimed to investigate the occurrence of neuropsychological dysfunction in former workers of fluorescent lamps factories that were exposed to mercury vapor (years after cessation of exposure), diagnosed with chronic mercurialism, and to investigate the effects of such exposure on the Autonomic Nervous System (ANS) using the non-invasive method of dynamic pupillometry. The exposed group and a control group matched by age and educational level were evaluated by the Beck Depression Inventory and with the computerized neuropsychological battery CANTABeclipse - subtests of working memory (Spatial Span), spatial memory (Spatial Recognition Memory), visual memory (Pattern Recognition Memory) and action planning (Stockings of Cambridge). The ANS was assessed by dynamic pupillometry, which provides information on the operation on both the sympathetic and parasympathetic functions. Depression scores were significantly higher among the former workers when compared with the control group. The exposed group also showed significantly worse performance in most of the cognitive functions assessed. In the dynamic pupillometry test, former workers showed significantly lower response than the control group in the sympathetic response parameter (time of 75% of pupillary recovery at 10cd/m 2 luminance). Our study found indications that are suggestive of cognitive deficits and losses in sympathetic autonomic activity among patients occupationally exposed to mercury vapor. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. DIAGNOSING THE TYPE OF DYNAMICS OF SOCIO-ECONOMIC SYSTEMS USING TOPOLOGICAL TESTS (THE EU IS TAKEN AS AN EXAMPLE

    Directory of Open Access Journals (Sweden)

    M. Golovanenko

    2013-09-01

    Full Text Available The possibility of practical realization of the simplest elements of topological tests that are used to identify the type of systems’ dynamics is considered in the article. The tests were fulfilled by the means of standard instruments of Microsoft Excel. The analysis of time series of industrial production indices of EU 17 countries as a whole and individual countries, such as Germany, France, Great Britain and Greece has shown that these series are characterized by existence of attractors. This can be interpreted as a sign of existence of deterministic chaos and evidence of the systems’ ability for self-organization and self-regulation. However, a separate area is identified for Greece, where the dynamics of the time series transforms into a random. The area can be interpreted as a sign of “overheating” economy of Greece, which took place before the global crisis and thus deprived the economy of adaptive properties.

  2. Small test SDHW systems

    DEFF Research Database (Denmark)

    Vejen, Niels Kristian

    1999-01-01

    Three small test SDHW systems was tested in a laboratory test facility.The three SDHW systems where all based on the low flow principe and a mantle tank but the design of the systems where different.......Three small test SDHW systems was tested in a laboratory test facility.The three SDHW systems where all based on the low flow principe and a mantle tank but the design of the systems where different....

  3. Steady-state and dynamic evaluation of the electric propulsion system test bed vehicle on a road load simulator

    Science.gov (United States)

    Dustin, M. O.

    1983-01-01

    The propulsion system of the Lewis Research Center's electric propulsion system test bed vehicle was tested on the road load simulator under the DOE Electric and Hybrid Vehicle Program. This propulsion system, consisting of a series-wound dc motor controlled by an infinitely variable SCR chopper and an 84-V battery pack, is typical of those used in electric vehicles made in 1976. Steady-state tests were conducted over a wide range of differential output torques and vehicle speeds. Efficiencies of all of the components were determined. Effects of temperature and voltage variations on the motor and the effect of voltage changes on the controller were examined. Energy consumption and energy efficiency for the system were determined over the B and C driving schedules of the SAE J227a test procedure.

  4. Dynamics of Information Systems

    CERN Document Server

    Hirsch, Michael J; Murphey, Robert

    2010-01-01

    Our understanding of information and information dynamics has outgrown classical information theory. This book presents the research explaining the importance of information in the evolution of a distributed or networked system. It presents techniques for measuring the value or significance of information within the context of a system

  5. Max Launch Abort System (MLAS) Pad Abort Test Vehicle (PATV) II Attitude Control System (ACS) Integration and Pressurization Subsystem Dynamic Random Vibration Analysis

    Science.gov (United States)

    Ekrami, Yasamin; Cook, Joseph S.

    2011-01-01

    In order to mitigate catastrophic failures on future generation space vehicles, engineers at the National Aeronautics and Space Administration have begun to integrate a novel crew abort systems that could pull a crew module away in case of an emergency at the launch pad or during ascent. The Max Launch Abort System (MLAS) is a recent test vehicle that was designed as an alternative to the baseline Orion Launch Abort System (LAS) to demonstrate the performance of a "tower-less" LAS configuration under abort conditions. The MLAS II test vehicle will execute a propulsive coast stabilization maneuver during abort to control the vehicles trajectory and thrust. To accomplish this, the spacecraft will integrate an Attitude Control System (ACS) with eight hypergolic monomethyl hydrazine liquid propulsion engines that are capable of operating in a quick pulsing mode. Two main elements of the ACS include a propellant distribution subsystem and a pressurization subsystem to regulate the flow of pressurized gas to the propellant tanks and the engines. The CAD assembly of the Attitude Control System (ACS) was configured and integrated into the Launch Abort Vehicle (LAV) design. A dynamic random vibration analysis was conducted on the Main Propulsion System (MPS) helium pressurization panels to assess the response of the panel and its components under increased gravitational acceleration loads during flight. The results indicated that the panels fundamental and natural frequencies were farther from the maximum Acceleration Spectral Density (ASD) vibrations which were in the range of 150-300 Hz. These values will direct how the components will be packaged in the vehicle to reduce the effects high gravitational loads.

  6. Dynamic analysis and vibration testing of CFRP drive-line system used in heavy-duty machine tool

    OpenAIRE

    Mo Yang; Lin Gui; Yefa Hu; Guoping Ding; Chunsheng Song

    2018-01-01

    Low critical rotary speed and large vibration in the metal drive-line system of heavy-duty machine tool affect the machining precision seriously. Replacing metal drive-line with the CFRP drive-line can effectively solve this problem. Based on the composite laminated theory and the transfer matrix method (TMM), this paper puts forward a modified TMM to analyze dynamic characteristics of CFRP drive-line system. With this modified TMM, the CFRP drive-line of a heavy vertical miller is analyzed. ...

  7. Dynamics of glassy systems

    International Nuclear Information System (INIS)

    Cugliandolo, Leticia F.

    2003-09-01

    These lecture notes can be read in two ways. The first two Sections contain a review of the phenomenology of several physical systems with slow nonequilibrium dynamics. In the Conclusions we summarize the scenario for this temporal evolution derived from the solution to some solvable models (p spin and the like) that are intimately connected to the mode coupling approach (and similar ones) to super-cooled liquids. At the end we list a number of open problems of great relevance in this context. These Sections can be read independently of the body of the paper where we present some of the basic analytic techniques used to study the out of equilibrium dynamics of classical and quantum models with and without disorder. We start the technical part by briefly discussing the role played by the environment and by introducing and comparing its representation in the equilibrium and dynamic treatment of classical and quantum systems. We next explain the role played by explicit quenched disorder in both approaches. Later on we focus on analytical techniques; we expand on the dynamic functional methods, and the diagrammatic expansions and resummations used to derive macroscopic equations from the microscopic dynamics. We show why the macroscopic dynamic equations for disordered models and those resulting from self-consistent approximations to non-disordered ones coincide. We review some generic properties of dynamic systems evolving out of equilibrium like the modifications of the fluctuation-dissipation theorem, generic scaling forms of the correlation functions, etc. Finally we solve a family of mean-field models. The connection between the dynamic treatment and the analysis of the free-energy landscape of these models is also presented. We use pedagogical examples all along these lectures to illustrate the properties and results. (author)

  8. Butschli Dynamic Droplet System

    DEFF Research Database (Denmark)

    Armstrong, R.; Hanczyc, M.

    2013-01-01

    Dynamical oil-water systems such as droplets display lifelike properties and may lend themselves to chemical programming to perform useful work, specifically with respect to the built environment. We present Butschli water-in-oil droplets as a model for further investigation into the development...... reconstructed the Butschli system and observed its life span under a light microscope, observing chemical patterns and droplet behaviors in nearly three hundred replicate experiments. Self-organizing patterns were observed, and during this dynamic, embodied phase the droplets provided a means of introducing...... temporal and spatial order in the system with the potential for chemical programmability. The authors propose that the discrete formation of dynamic droplets, characterized by their lifelike behavior patterns, during a variable window of time (from 30 s to 30 min after the addition of alkaline water...

  9. Complexity in Dynamical Systems

    Science.gov (United States)

    Moore, Cristopher David

    The study of chaos has shown us that deterministic systems can have a kind of unpredictability, based on a limited knowledge of their initial conditions; after a finite time, the motion appears essentially random. This observation has inspired a general interest in the subject of unpredictability, and more generally, complexity; how can we characterize how "complex" a dynamical system is?. In this thesis, we attempt to answer this question with a paradigm of complexity that comes from computer science, we extract sets of symbol sequences, or languages, from a dynamical system using standard methods of symbolic dynamics; we then ask what kinds of grammars or automata are needed a generate these languages. This places them in the Chomsky heirarchy, which in turn tells us something about how subtle and complex the dynamical system's behavior is. This gives us insight into the question of unpredictability, since these automata can also be thought of as computers attempting to predict the system. In the culmination of the thesis, we find a class of smooth, two-dimensional maps which are equivalent to the highest class in the Chomsky heirarchy, the turning machine; they are capable of universal computation. Therefore, these systems possess a kind of unpredictability qualitatively different from the usual "chaos": even if the initial conditions are known exactly, questions about the system's long-term dynamics are undecidable. No algorithm exists to answer them. Although this kind of unpredictability has been discussed in the context of distributed, many-degree-of -freedom systems (for instance, cellular automata) we believe this is the first example of such phenomena in a smooth, finite-degree-of-freedom system.

  10. Complexified dynamical systems

    International Nuclear Information System (INIS)

    Bender, Carl M; Holm, Darryl D; Hook, Daniel W

    2007-01-01

    Many dynamical systems, such as the Lotka-Volterra predator-prey model and the Euler equations for the free rotation of a rigid body, are PT symmetric. The standard and well-known real solutions to such dynamical systems constitute an infinitessimal subclass of the full set of complex solutions. This paper examines a subset of the complex solutions that contains the real solutions, namely those having PT symmetry. The condition of PT symmetry selects out complex solutions that are periodic. (fast track communication)

  11. Charging and discharging tests for obtaining an accurate dynamic electro-thermal model of high power lithium-ion pack system for hybrid and EV applications

    DEFF Research Database (Denmark)

    Mihet-Popa, Lucian; Camacho, Oscar Mauricio Forero; Nørgård, Per Bromand

    2013-01-01

    This paper presents a battery test platform including two Li-ion battery designed for hybrid and EV applications, and charging/discharging tests under different operating conditions carried out for developing an accurate dynamic electro-thermal model of a high power Li-ion battery pack system....... The aim of the tests has been to study the impact of the battery degradation and to find out the dynamic characteristics of the cells including nonlinear open circuit voltage, series resistance and parallel transient circuit at different charge/discharge currents and cell temperature. An equivalent...... circuit model, based on the runtime battery model and the Thevenin circuit model, with parameters obtained from the tests and depending on SOC, current and temperature has been implemented in MATLAB/Simulink and Power Factory. A good alignment between simulations and measurements has been found....

  12. Nonautonomous dynamical systems

    CERN Document Server

    Kloeden, Peter E

    2011-01-01

    The theory of nonautonomous dynamical systems in both of its formulations as processes and skew product flows is developed systematically in this book. The focus is on dissipative systems and nonautonomous attractors, in particular the recently introduced concept of pullback attractors. Linearization theory, invariant manifolds, Lyapunov functions, Morse decompositions and bifurcations for nonautonomous systems and set-valued generalizations are also considered as well as applications to numerical approximations, switching systems and synchronization. Parallels with corresponding theories of control and random dynamical systems are briefly sketched. With its clear and systematic exposition, many examples and exercises, as well as its interesting applications, this book can serve as a text at the beginning graduate level. It is also useful for those who wish to begin their own independent research in this rapidly developing area.

  13. Joint Installed System Test Facility (JISTF) Infrared Sensor Simulation/Stimulation Enhancement: Dynamic Virtual Reality Simulation/Stimulation Technologies for Test, Evaluaiton, and Training

    National Research Council Canada - National Science Library

    Joyner, Tom

    1999-01-01

    ... to maximize use of scarce testing and training investment resources. This paper addresses the capabilities and development of the JISTF IRSS system under the sponsorship of the Office of the Secretary of Defense (OSD...

  14. System dynamics with interaction discontinuity

    CERN Document Server

    Luo, Albert C J

    2015-01-01

    This book describes system dynamics with discontinuity caused by system interactions and presents the theory of flow singularity and switchability at the boundary in discontinuous dynamical systems. Based on such a theory, the authors address dynamics and motion mechanism of engineering discontinuous systems due to interaction. Stability and bifurcations of fixed points in nonlinear discrete dynamical systems are presented, and mapping dynamics are developed for analytical predictions of periodic motions in engineering discontinuous dynamical systems. Ultimately, the book provides an alternative way to discuss the periodic and chaotic behaviors in discontinuous dynamical systems.

  15. Dynamic testing of adhesive joints using a shock testing machine

    NARCIS (Netherlands)

    Aanhold, J.E. van; Weersink, A.F.J.; Ludolphy, J.W.L.

    1998-01-01

    A light-weight shock testing machine, designed for type approval testing of naval equipment up to 300 kg mass, has been modified into a dynamic tensile test rig. This enables to test structural details for high rate dynamic tensile loadings such as occur during underwater shock. The maximum capacity

  16. Finite element modeling of a shaking table test to evaluate the dynamic behaviour of a soil-foundation system

    International Nuclear Information System (INIS)

    Abate, G.; Massimino, M. R.; Maugeri, M.

    2008-01-01

    The deep investigation of soil-foundation interaction behaviour during earthquakes represent one of the key-point for a right seismic design of structures, which can really behave well during earthquake, avoiding dangerous boundary conditions, such as weak foundations supporting the superstructures. The paper presents the results of the FEM modeling of a shaking table test involving a concrete shallow foundation resting on a Leighton Buzzard sand deposit. The numerical simulation is performed using a cap-hardening elasto-plastic constitutive model for the soil and specific soil-foundation contacts to allow slipping and up-lifting phenomena. Thanks to the comparison between experimental and numerical results, the power and the limits of the proposed numerical model are focused. Some aspects of the dynamic soil-foundation interaction are also pointed out

  17. What are System Dynamics Insights?

    OpenAIRE

    Stave, K.; Zimmermann, N. S.; Kim, H.

    2016-01-01

    This paper explores the concept of system dynamics insights. In our field, the term “insight” is generally understood to mean dynamic insight, that is, a deep understanding about the relationship between structure and behavior. We argue this is only one aspect of the range of insights possible from system dynamics activities, and describe a broader range of potential system dynamics insights. We also propose an initial framework for discussion that relates different types of system dynamics a...

  18. Three-body dynamics in one dimension: a test model for the three-nucleon system with irreducible pionic diagrams

    International Nuclear Information System (INIS)

    Melde, T.; Canton, L.; Svenne, J.P.

    2002-01-01

    We formulate the three-body problem in one dimension in terms of the (Faddeev-type) integral equation approach. As an application, we develop a spinless, one-dimensional (1-D) model that mimics three-nucleon dynamics in one dimension. Using simple two-body potentials that reproduce the deuteron binding, we obtain that the three-body system binds at about 7.5 MeV. We then consider two types of residual pionic corrections in the dynamical equation; one related to the 2π-exchange three-body diagram, the other to the 1π-exchange three-body diagram. We find that the first contribution can produce an additional binding effect of about 0.9 MeV. The second term produces smaller binding effects, which are, however, dependent on the uncertainty in the off-shell extrapolation of the two-body t-matrix. This presents interesting analogies with what occurs in three dimensions. The paper also discusses the general three-particle quantum scattering problem, for motion restricted to the fall line. (author)

  19. Interactive Dynamic-System Simulation

    CERN Document Server

    Korn, Granino A

    2010-01-01

    Showing you how to use personal computers for modeling and simulation, Interactive Dynamic-System Simulation, Second Edition provides a practical tutorial on interactive dynamic-system modeling and simulation. It discusses how to effectively simulate dynamical systems, such as aerospace vehicles, power plants, chemical processes, control systems, and physiological systems. Written by a pioneer in simulation, the book introduces dynamic-system models and explains how software for solving differential equations works. After demonstrating real simulation programs with simple examples, the author

  20. Using Participatory System Dynamics Modeling to Examine the Local HIV Test and Treatment Care Continuum in Order to Reduce Community Viral Load.

    Science.gov (United States)

    Weeks, Margaret R; Li, Jianghong; Lounsbury, David; Green, Helena Danielle; Abbott, Maryann; Berman, Marcie; Rohena, Lucy; Gonzalez, Rosely; Lang, Shawn; Mosher, Heather

    2017-12-01

    Achieving community-level goals to eliminate the HIV epidemic requires coordinated efforts through community consortia with a common purpose to examine and critique their own HIV testing and treatment (T&T) care system and build effective tools to guide their efforts to improve it. Participatory system dynamics (SD) modeling offers conceptual, methodological, and analytical tools to engage diverse stakeholders in systems conceptualization and visual mapping of dynamics that undermine community-level health outcomes and identify those that can be leveraged for systems improvement. We recruited and engaged a 25-member multi-stakeholder Task Force, whose members provide or utilize HIV-related services, to participate in SD modeling to examine and address problems of their local HIV T&T service system. Findings from the iterative model building sessions indicated Task Force members' increasingly complex understanding of the local HIV care system and demonstrated their improved capacity to visualize and critique multiple models of the HIV T&T service system and identify areas of potential leverage. Findings also showed members' enhanced communication and consensus in seeking deeper systems understanding and options for solutions. We discuss implications of using these visual SD models for subsequent simulation modeling of the T&T system and for other community applications to improve system effectiveness. © Society for Community Research and Action 2017.

  1. Solar System Dynamics

    Science.gov (United States)

    Wisdom, Jack

    2002-01-01

    In these 18 years, the research has touched every major dynamical problem in the solar system, including: the effect of chaotic zones on the distribution of asteroids, the delivery of meteorites along chaotic pathways, the chaotic motion of Pluto, the chaotic motion of the outer planets and that of the whole solar system, the delivery of short period comets from the Kuiper belt, the tidal evolution of the Uranian arid Galilean satellites, the chaotic tumbling of Hyperion and other irregular satellites, the large chaotic variations of the obliquity of Mars, the evolution of the Earth-Moon system, and the resonant core- mantle dynamics of Earth and Venus. It has introduced new analytical and numerical tools that are in widespread use. Today, nearly every long-term integration of our solar system, its subsystems, and other solar systems uses algorithms that was invented. This research has all been primarily Supported by this sequence of PGG NASA grants. During this period published major investigations of tidal evolution of the Earth-Moon system and of the passage of the Earth and Venus through non-linear core-mantle resonances were completed. It has published a major innovation in symplectic algorithms: the symplectic corrector. A paper was completed on non-perturbative hydrostatic equilibrium.

  2. Structural dynamics and fracture mechanics calculations of the behaviour of a DN 425 test piping system subjected to transient loading by water hammer

    International Nuclear Information System (INIS)

    Kussmaul, K.; Kobes, E.; Diem, H.; Schrammel, D.; Brosi, S.

    1994-01-01

    Within the scope of the German HDR safety programme, several tests were carried out to investigate transient pipe loading initiated by a simulated double-ended guillotine break event, and subsequent closure of a feedwater check valve (water hammer, blow-down). Numerical analyses by means of finite element programmes were performed in parallel to the experiments. Using water hammer tests of a DN 425 piping system with predamaged components, the procedure of such analyses will be demonstrated. The results are presented, beginning with structural dynamic calculations of the undamaged piping; followed by coupling of structural dynamics and fracture mechanics computations with simple flaw elements (line spring); and finishing with costly three-dimensional fracture mechanics analyses. A good description of the real piping behaviour can be made by the numerical methods, even in the case of high plastification processes. ((orig.))

  3. Programmable automated transistor test system

    International Nuclear Information System (INIS)

    Truong, L.V.; Sundberg, G.R.

    1986-01-01

    The paper describes a programmable automated transistor test system (PATTS) and its utilization to evaluate bipolar transistors and Darlingtons, and such MOSFET and special types as can be accommodated with the PATTS base-drive. An application of a pulsed power technique at low duty cycles in a non-destructive test is used to examine the dynamic switching characteristic curves of power transistors. Data collection, manipulation, storage, and output are operator interactive but are guided and controlled by the system software. In addition a library of test data is established on disks, tapes, and hard copies for future reference

  4. OOK power model based dynamic error testing for smart electricity meter

    International Nuclear Information System (INIS)

    Wang, Xuewei; Chen, Jingxia; Jia, Xiaolu; Zhu, Meng; Yuan, Ruiming; Jiang, Zhenyu

    2017-01-01

    This paper formulates the dynamic error testing problem for a smart meter, with consideration and investigation of both the testing signal and the dynamic error testing method. To solve the dynamic error testing problems, the paper establishes an on-off-keying (OOK) testing dynamic current model and an OOK testing dynamic load energy (TDLE) model. Then two types of TDLE sequences and three modes of OOK testing dynamic power are proposed. In addition, a novel algorithm, which helps to solve the problem of dynamic electric energy measurement’s traceability, is derived for dynamic errors. Based on the above researches, OOK TDLE sequence generation equipment is developed and a dynamic error testing system is constructed. Using the testing system, five kinds of meters were tested in the three dynamic power modes. The test results show that the dynamic error is closely related to dynamic power mode and the measurement uncertainty is 0.38%. (paper)

  5. OOK power model based dynamic error testing for smart electricity meter

    Science.gov (United States)

    Wang, Xuewei; Chen, Jingxia; Yuan, Ruiming; Jia, Xiaolu; Zhu, Meng; Jiang, Zhenyu

    2017-02-01

    This paper formulates the dynamic error testing problem for a smart meter, with consideration and investigation of both the testing signal and the dynamic error testing method. To solve the dynamic error testing problems, the paper establishes an on-off-keying (OOK) testing dynamic current model and an OOK testing dynamic load energy (TDLE) model. Then two types of TDLE sequences and three modes of OOK testing dynamic power are proposed. In addition, a novel algorithm, which helps to solve the problem of dynamic electric energy measurement’s traceability, is derived for dynamic errors. Based on the above researches, OOK TDLE sequence generation equipment is developed and a dynamic error testing system is constructed. Using the testing system, five kinds of meters were tested in the three dynamic power modes. The test results show that the dynamic error is closely related to dynamic power mode and the measurement uncertainty is 0.38%.

  6. Recent developments in dynamic testing of materials

    Directory of Open Access Journals (Sweden)

    Gilat Amos

    2015-01-01

    Full Text Available New techniques for dynamic characterization of materials that have been developed in the last three years (since the last DYMAT conference in 2012, and results from recent dynamic testing of Inconel 718 are presented. The first development is a dynamic punch test in which three dimensional Digital Image Correlation (DIC is used to measure the deformation of the rear surface of a specimen as it being penetrated. The second experimental technique that is under development is a dynamic tension experiment in which full-field strain measurement with DIC and full-field temperature measurement are done simultaneously during the test.

  7. Programmable, automated transistor test system

    Science.gov (United States)

    Truong, L. V.; Sundburg, G. R.

    1986-01-01

    A programmable, automated transistor test system was built to supply experimental data on new and advanced power semiconductors. The data will be used for analytical models and by engineers in designing space and aircraft electric power systems. A pulsed power technique was used at low duty cycles in a nondestructive test to examine the dynamic switching characteristic curves of power transistors in the 500 to 1000 V, 10 to 100 A range. Data collection, manipulation, storage, and output are operator interactive but are guided and controlled by the system software.

  8. Cosmological dynamical systems

    CERN Document Server

    Leon, Genly

    2011-01-01

    In this book are studied, from the perspective of the dynamical systems, several Universe models. In chapter 1 we give a bird's eye view on cosmology and cosmological problems. Chapter 2 is devoted to a brief review on some results and useful tools from the qualitative theory of dynamical systems. They provide the theoretical basis for the qualitative study of concrete cosmological models. Chapters 1 and 2 are a review of well-known results. Chapters 3, 4, 5 and 6 are devoted to our main results. In these chapters are extended and settled in a substantially different, more strict mathematical language, several results obtained by one of us in arXiv:0812.1013 [gr-qc]; arXiv:1009.0689 [gr-qc]; arXiv:0904.1577[gr-qc]; and arXiv:0909.3571 [hep-th]. In chapter 6, we provide a different approach to the subject discussed in astro-ph/0503478. Additionally, we perform a Poincar\\'e compactification process allowing to construct a global phase space containing all the cosmological information in both finite and infinite...

  9. Dynamics of stochastic systems

    CERN Document Server

    Klyatskin, Valery I

    2005-01-01

    Fluctuating parameters appear in a variety of physical systems and phenomena. They typically come either as random forces/sources, or advecting velocities, or media (material) parameters, like refraction index, conductivity, diffusivity, etc. The well known example of Brownian particle suspended in fluid and subjected to random molecular bombardment laid the foundation for modern stochastic calculus and statistical physics. Other important examples include turbulent transport and diffusion of particle-tracers (pollutants), or continuous densities (''''oil slicks''''), wave propagation and scattering in randomly inhomogeneous media, for instance light or sound propagating in the turbulent atmosphere.Such models naturally render to statistical description, where the input parameters and solutions are expressed by random processes and fields.The fundamental problem of stochastic dynamics is to identify the essential characteristics of system (its state and evolution), and relate those to the input parameters of ...

  10. System Performance and Testing

    NARCIS (Netherlands)

    Frei, U.; Oversloot, H.

    2004-01-01

    This chapter compares and contrasts the system performance of two widely used solar thermal systems using testing and simulation programs. Solar thermal systems are used in many countries for heating domestically used water. In addition to the simple thermosiphon systems, better designed pumped

  11. Computational hydrodynamic comparison of a mini vessel and a USP 2 dissolution testing system to predict the dynamic operating conditions for similarity of dissolution performance.

    Science.gov (United States)

    Wang, Bing; Bredael, Gerard; Armenante, Piero M

    2018-03-25

    The hydrodynamic characteristics of a mini vessel and a USP 2 dissolution testing system were obtained and compared to predict the tablet-liquid mass transfer coefficient from velocity distributions near the tablet and establish the dynamic operating conditions under which dissolution in mini vessels could be conducted to generate concentration profiles similar to those in the USP 2. Velocity profiles were obtained experimentally using Particle Image Velocimetry (PIV). Computational Fluid Dynamics (CFD) was used to predict the velocity distribution and strain rate around a model tablet. A CFD-based mass transfer model was also developed. When plotted against strain rate, the predicted tablet-liquid mass transfer coefficient was found to be independent of the system where it was obtained, implying that a tablet would dissolve at the same rate in both systems provided that the concentration gradient between the tablet surface and the bulk is the same, the tablet surface area per unit liquid volume is identical, and the two systems are operated at the appropriate agitation speeds specified in this work. The results of this work will help dissolution scientists operate mini vessels so as to predict the dissolution profiles in the USP 2, especially during the early stages of drug development. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Synchronization dynamics of two different dynamical systems

    International Nuclear Information System (INIS)

    Luo, Albert C.J.; Min Fuhong

    2011-01-01

    Highlights: → Synchronization dynamics of two distinct dynamical systems. → Synchronization, de-synchronization and instantaneous synchronization. → A controlled pendulum synchronizing with the Duffing oscillator. → Synchronization invariant set. → Synchronization parameter map. - Abstract: In this paper, synchronization dynamics of two different dynamical systems is investigated through the theory of discontinuous dynamical systems. The necessary and sufficient conditions for the synchronization, de-synchronization and instantaneous synchronization (penetration or grazing) are presented. Using such a synchronization theory, the synchronization of a controlled pendulum with the Duffing oscillator is systematically discussed as a sampled problem, and the corresponding analytical conditions for the synchronization are presented. The synchronization parameter study is carried out for a better understanding of synchronization characteristics of the controlled pendulum and the Duffing oscillator. Finally, the partial and full synchronizations of the controlled pendulum with periodic and chaotic motions are presented to illustrate the analytical conditions. The synchronization of the Duffing oscillator and pendulum are investigated in order to show the usefulness and efficiency of the methodology in this paper. The synchronization invariant domain is obtained. The technique presented in this paper should have a wide spectrum of applications in engineering. For example, this technique can be applied to the maneuvering target tracking, and the others.

  13. Molecular dynamics simulation of impact test

    International Nuclear Information System (INIS)

    Akahoshi, Y.; Schmauder, S.; Ludwig, M.

    1998-01-01

    This paper describes an impact test by molecular dynamics (MD) simulation to evaluate embrittlement of bcc Fe at different temperatures. A new impact test model is developed for MD simulation. The typical fracture behaviors show transition from brittle to ductile fracture, and a history of the impact loads also demonstrates its transition. We conclude that the impact test by MD could be feasible. (orig.)

  14. Molecular dynamics simulation of impact test

    Energy Technology Data Exchange (ETDEWEB)

    Akahoshi, Y. [Kyushu Inst. of Tech., Kitakyushu, Fukuoka (Japan); Schmauder, S.; Ludwig, M. [Stuttgart Univ. (Germany). Staatliche Materialpruefungsanstalt

    1998-11-01

    This paper describes an impact test by molecular dynamics (MD) simulation to evaluate embrittlement of bcc Fe at different temperatures. A new impact test model is developed for MD simulation. The typical fracture behaviors show transition from brittle to ductile fracture, and a history of the impact loads also demonstrates its transition. We conclude that the impact test by MD could be feasible. (orig.)

  15. Chaos for Discrete Dynamical System

    Directory of Open Access Journals (Sweden)

    Lidong Wang

    2013-01-01

    Full Text Available We prove that a dynamical system is chaotic in the sense of Martelli and Wiggins, when it is a transitive distributively chaotic in a sequence. Then, we give a sufficient condition for the dynamical system to be chaotic in the strong sense of Li-Yorke. We also prove that a dynamical system is distributively chaotic in a sequence, when it is chaotic in the strong sense of Li-Yorke.

  16. Dynamical Systems for Creative Technology

    NARCIS (Netherlands)

    van Amerongen, J.

    2010-01-01

    Dynamical Systems for Creative Technology gives a concise description of the physical properties of electrical, mechanical and hydraulic systems. Emphasis is placed on modelling the dynamical properties of these systems. By using a system’s approach it is shown that a limited number of mathematical

  17. ELECTROFORCE 3330 TEST SYSTEM

    Data.gov (United States)

    Federal Laboratory Consortium — The Bose Electroforce 3330 is a test system with an axial electromagnetic linear motor, a torsional motor, and an environmental chamber for high and low temperature...

  18. Automatic Test Systems Aquisition

    National Research Council Canada - National Science Library

    1994-01-01

    We are providing this final memorandum report for your information and use. This report discusses the efforts to achieve commonality in standards among the Military Departments as part of the DoD policy for automatic test systems (ATS...

  19. Dynamics of vehicle-road coupled system

    CERN Document Server

    Yang, Shaopu; Li, Shaohua

    2015-01-01

    Vehicle dynamics and road dynamics are usually considered to be two largely independent subjects. In vehicle dynamics, road surface roughness is generally regarded as random excitation of the vehicle, while in road dynamics, the vehicle is generally regarded as a moving load acting on the pavement. This book suggests a new research concept to integrate the vehicle and the road system with the help of a tire model, and establishes a cross-subject research framework dubbed vehicle-pavement coupled system dynamics. In this context, the dynamics of the vehicle, road and the vehicle-road coupled system are investigated by means of theoretical analysis, numerical simulations and field tests. This book will be a valuable resource for university professors, graduate students and engineers majoring in automotive design, mechanical engineering, highway engineering and other related areas. Shaopu Yang is a professor and deputy president of Shijiazhuang Tiedao University, China; Liqun Chen is a professor at Shanghai Univ...

  20. Dynamic of HIV-testing after arrival in France for migrants from sub-Saharan Africa: The role of both health and social care systems.

    Science.gov (United States)

    Limousi, Frédérike; Lert, France; Desgrées du Loû, Annabel; Dray-Spira, Rosemary; Lydié, Nathalie

    2017-01-01

    HIV testing is an important tool in the management of the HIV epidemic among key populations. We aimed to explore the dynamic of first-time HIV testing in France for sub-Saharan migrants after their arrival. ANRS-Parcours is a retrospective life-event survey conducted from 2012 to 2013 in healthcare facilities in the Paris region, among 926 sub-Saharan HIV-infected migrants and 763 non-infected migrants. After describing the time to first HIV test in France and associated circumstances, we performed a discrete-time logistic regression to analyze the influence of socioeconomic position, contact with the healthcare system and sexual behaviors, on first-time HIV testing in France in migrants who arrived after 2000. Median first-time HIV testing occurred during the second year spent in France for non-infected men and women in both groups, and during the first year for men of the HIV group. The probability of testing increased with hospitalization and pregnancy for women of both groups. For non-infected men unemployment and absence of a residence permit were associated with an increased probability of HIV testing [respectively, OR = 2.2 (1.2-4.1) and OR = 2.0 (1.1-3.5)]. Unemployment was also associated with an increased probability of first-time HIV-testing for women of the HIV group [OR: 1.7 (1.0-2.7)]. Occasional and multiple sexual relationships were associated with an increased probability of first-time testing only for HIV-infected women [OR: 2.2 (1.2-4.0) and OR = 2.4 (1.3-4.6)]. Access to first HIV testing in France is promoted by contact with the health care system and is facilitated for unemployed and undocumented migrants after arrival.However, testing should be offered more systematically and repeated in order to reduce time between HIV infection and diagnosis, especially for deprived people which are particularly vulnerable regarding HIV infection.

  1. Nonlinear Dynamic Inversion Baseline Control Law: Flight-Test Results for the Full-scale Advanced Systems Testbed F/A-18 Airplane

    Science.gov (United States)

    Miller, Christopher J.

    2011-01-01

    A model reference nonlinear dynamic inversion control law has been developed to provide a baseline controller for research into simple adaptive elements for advanced flight control laws. This controller has been implemented and tested in a hardware-in-the-loop simulation and in flight. The flight results agree well with the simulation predictions and show good handling qualities throughout the tested flight envelope with some noteworthy deficiencies highlighted both by handling qualities metrics and pilot comments. Many design choices and implementation details reflect the requirements placed on the system by the nonlinear flight environment and the desire to keep the system as simple as possible to easily allow the addition of the adaptive elements. The flight-test results and how they compare to the simulation predictions are discussed, along with a discussion about how each element affected pilot opinions. Additionally, aspects of the design that performed better than expected are presented, as well as some simple improvements that will be suggested for follow-on work.

  2. Fault diagnosis for dynamic power system

    International Nuclear Information System (INIS)

    Thabet, A.; Abdelkrim, M.N.; Boutayeb, M.; Didier, G.; Chniba, S.

    2011-01-01

    The fault diagnosis problem for dynamic power systems is treated, the nonlinear dynamic model based on a differential algebraic equations is transformed with reduced index to a simple dynamic model. Two nonlinear observers are used for generating the fault signals for comparison purposes, one of them being an extended Kalman estimator and the other a new extended kalman filter with moving horizon with a study of convergence based on the choice of matrix of covariance of the noises of system and measurements. The paper illustrates a simulation study applied on IEEE 3 buses test system.

  3. Regression testing Ajax applications : Coping with dynamism

    NARCIS (Netherlands)

    Roest, D.; Mesbah, A.; Van Deursen, A.

    2009-01-01

    Note: This paper is a pre-print of: Danny Roest, Ali Mesbah and Arie van Deursen. Regression Testing AJAX Applications: Coping with Dynamism. In Proceedings of the 3rd International Conference on Software Testing, Verification and Validation (ICST’10), Paris, France. IEEE Computer Society, 2010.

  4. Management of complex dynamical systems

    Science.gov (United States)

    MacKay, R. S.

    2018-02-01

    Complex dynamical systems are systems with many interdependent components which evolve in time. One might wish to control their trajectories, but a more practical alternative is to control just their statistical behaviour. In many contexts this would be both sufficient and a more realistic goal, e.g. climate and socio-economic systems. I refer to it as ‘management’ of complex dynamical systems. In this paper, some mathematics for management of complex dynamical systems is developed in the weakly dependent regime, and questions are posed for the strongly dependent regime.

  5. Modelling the heat dynamics of a monitored Test Reference Environment for Building Integrated Photovoltaic systems using stochastic differential equations

    DEFF Research Database (Denmark)

    Lodi, C.; Bacher, Peder; Cipriano, J.

    2012-01-01

    reduce the ventilation thermal losses of the building by pre-heating the fresh air. Furthermore, by decreasing PV module temperature, the ventilation air heat extraction can simultaneously increase electrical and thermal energy production of the building. A correct prediction of the PV module temperature...... and heat transfer coefficients is fundamental in order to improve the thermo-electrical production.The considered grey-box models are composed of a set of continuous time stochastic differential equations, holding the physical description of the system, combined with a set of discrete time measurement......This paper deals with grey-box modelling of the energy transfer of a double skin Building Integrated Photovoltaic (BIPV) system. Grey-box models are based on a combination of prior physical knowledge and statistics, which enable identification of the unknown parameters in the system and accurate...

  6. Controlling Uncertain Dynamical Systems

    Indian Academy of Sciences (India)

    Author Affiliations. N Ananthkrishnan1 Rashi Bansal2. Head, CAE Analysis & Design Zeus Numerix Pvt Ltd. M-03, SINE, IIT Bombay Powai Mumbai 400076, India. MTech (Aerospace Engineering) with specialization in Dynamics & Control from IIT Bombay.

  7. Dynamic Reconfiguration in Mobile Systems

    NARCIS (Netherlands)

    Smit, Gerardus Johannes Maria; Glesner, Manfred; Zipf, Peter; Smit, L.T.; Havinga, Paul J.M.; Heysters, P.M.; Renovell, Michel; Rosien, M.A.J.

    Dynamically reconfigurable systems have the potential of realising efficient systems as well as providing adaptability to changing system requirements. Such systems are suitable for future mobile multimedia systems that have limited battery resources, must handle diverse data types, and must operate

  8. Ergodic theory and dynamical systems

    CERN Document Server

    Coudène, Yves

    2016-01-01

    This textbook is a self-contained and easy-to-read introduction to ergodic theory and the theory of dynamical systems, with a particular emphasis on chaotic dynamics. This book contains a broad selection of topics and explores the fundamental ideas of the subject. Starting with basic notions such as ergodicity, mixing, and isomorphisms of dynamical systems, the book then focuses on several chaotic transformations with hyperbolic dynamics, before moving on to topics such as entropy, information theory, ergodic decomposition and measurable partitions. Detailed explanations are accompanied by numerous examples, including interval maps, Bernoulli shifts, toral endomorphisms, geodesic flow on negatively curved manifolds, Morse-Smale systems, rational maps on the Riemann sphere and strange attractors. Ergodic Theory and Dynamical Systems will appeal to graduate students as well as researchers looking for an introduction to the subject. While gentle on the beginning student, the book also contains a number of commen...

  9. Continuous waves probing in dynamic acoustoelastic testing

    Science.gov (United States)

    Scalerandi, M.; Gliozzi, A. S.; Ait Ouarabi, M.; Boubenider, F.

    2016-05-01

    Consolidated granular media display a peculiar nonlinear elastic behavior, which is normally analysed with dynamic ultrasonic testing exploiting the dependence on amplitude of different measurable quantities, such as the resonance frequency shift, the amount of harmonics generation, or the break of the superposition principle. However, dynamic testing allows measuring effects which are averaged over one (or more) cycles of the exciting perturbation. Dynamic acoustoelastic testing has been proposed to overcome this limitation and allow the determination of the real amplitude dependence of the modulus of the material. Here, we propose an implementation of the approach, in which the pulse probing waves are substituted by continuous waves. As a result, instead of measuring a time-of-flight as a function of the pump strain, we study the dependence of the resonance frequency on the strain amplitude, allowing to derive the same conclusions but with an easier to implement procedure.

  10. Stochastic runaway of dynamical systems

    International Nuclear Information System (INIS)

    Pfirsch, D.; Graeff, P.

    1984-10-01

    One-dimensional, stochastic, dynamical systems are well studied with respect to their stability properties. Less is known for the higher dimensional case. This paper derives sufficient and necessary criteria for the asymptotic divergence of the entropy (runaway) and sufficient ones for the moments of n-dimensional, stochastic, dynamical systems. The crucial implication is the incompressibility of their flow defined by the equations of motion in configuration space. Two possible extensions to compressible flow systems are outlined. (orig.)

  11. Dynamical systems in classical mechanics

    CERN Document Server

    Kozlov, V V

    1995-01-01

    This book shows that the phenomenon of integrability is related not only to Hamiltonian systems, but also to a wider variety of systems having invariant measures that often arise in nonholonomic mechanics. Each paper presents unique ideas and original approaches to various mathematical problems related to integrability, stability, and chaos in classical dynamics. Topics include… the inverse Lyapunov theorem on stability of equilibria geometrical aspects of Hamiltonian mechanics from a hydrodynamic perspective current unsolved problems in the dynamical systems approach to classical mechanics

  12. Dynamic Systems and Software

    DEFF Research Database (Denmark)

    Thomsen, Per Grove

    1996-01-01

    A one-dimensional model with axial discretization of engine components has been formulated using tha balance equations for mass energy and momentum and the ideal gas equation of state. ODE's that govern the dynamic behaviour of the regenerator matrix temperatures are included in the model. Known...

  13. Lectures on chaotic dynamical systems

    CERN Document Server

    Afraimovich, Valentin

    2002-01-01

    This book is devoted to chaotic nonlinear dynamics. It presents a consistent, up-to-date introduction to the field of strange attractors, hyperbolic repellers, and nonlocal bifurcations. The authors keep the highest possible level of "physical" intuition while staying mathematically rigorous. In addition, they explain a variety of important nonstandard algorithms and problems involving the computation of chaotic dynamics. The book will help readers who are not familiar with nonlinear dynamics to understand and appreciate sophisticated modern dynamical systems and chaos. Intended for courses in either mathematics, physics, or engineering, prerequisites are calculus, differential equations, and functional analysis.

  14. Dynamics robustness of cascading systems.

    Directory of Open Access Journals (Sweden)

    Jonathan T Young

    2017-03-01

    Full Text Available A most important property of biochemical systems is robustness. Static robustness, e.g., homeostasis, is the insensitivity of a state against perturbations, whereas dynamics robustness, e.g., homeorhesis, is the insensitivity of a dynamic process. In contrast to the extensively studied static robustness, dynamics robustness, i.e., how a system creates an invariant temporal profile against perturbations, is little explored despite transient dynamics being crucial for cellular fates and are reported to be robust experimentally. For example, the duration of a stimulus elicits different phenotypic responses, and signaling networks process and encode temporal information. Hence, robustness in time courses will be necessary for functional biochemical networks. Based on dynamical systems theory, we uncovered a general mechanism to achieve dynamics robustness. Using a three-stage linear signaling cascade as an example, we found that the temporal profiles and response duration post-stimulus is robust to perturbations against certain parameters. Then analyzing the linearized model, we elucidated the criteria of when signaling cascades will display dynamics robustness. We found that changes in the upstream modules are masked in the cascade, and that the response duration is mainly controlled by the rate-limiting module and organization of the cascade's kinetics. Specifically, we found two necessary conditions for dynamics robustness in signaling cascades: 1 Constraint on the rate-limiting process: The phosphatase activity in the perturbed module is not the slowest. 2 Constraints on the initial conditions: The kinase activity needs to be fast enough such that each module is saturated even with fast phosphatase activity and upstream changes are attenuated. We discussed the relevance of such robustness to several biological examples and the validity of the above conditions therein. Given the applicability of dynamics robustness to a variety of systems, it

  15. Advanced WEC Dynamics & Controls FY16 Testing Report

    Energy Technology Data Exchange (ETDEWEB)

    Coe, Ryan Geoffrey [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bacelli, Giorgio [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Wilson, David G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Patterson, David Charles [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-10-01

    A model-scale wave tank test was conducted in the interest of improving control systems design of wave energy converters (WECs). The success of most control strategies is based directly upon the availability of a reduced-order model with the ability to capture the dynamics of the system with sufficient accuracy. For this reason, the test described in this report, which is the first in a series of planned tests on WEC controls, focused on system identification (system ID) and model validation.

  16. Development of a dynamic short-term test method for installed thermal solar systems; Entwicklung eines dynamischen Kurzzeittestverfahrens fuer installierte thermische Solaranlagen

    Energy Technology Data Exchange (ETDEWEB)

    Beikircher, T.; Gut, M.; Kronthaler, P.; Oberdorf, C.; Schoelkopf, W. [Bayerisches Zentrum fuer Angewandte Energieforschung, Muenchen (Germany). Abt. Solarthermie und Biomasse

    1998-12-31

    A short-term test method for in-situ measurement of the collector field, pipelines and heat exchanger of large-surface solar systems was developed at ZAE Bayern, together with the necessary technical systems (mobile acquisition of meteorological data via telemetering, non-invasive surface temperature sensors and ultrasonic volume flow measuring instruments). Dynamic measurements were made for 11 days in a large-surface solar system of the ``Solarthermie 2000`` programme using the new measuring system. In order to optimize the evaluation procedure, the plant was simulated, and the influence of different models and operating conditions during the measurements on the prediction quality was investigated in detail. On this basis, it was possible to predict the long-term collector yield of the ZfS Hilden, which was measured for a period of 7 months, with an error of less than 5%. The method will be validated in two further industrial-scale systems. [Deutsch] Am ZAE Bayern wurde ein Kurzzeittestverfahren zur insitu-Vermessung des Kollektorkreises (Kollektorfeld, Rohrleitungen, Waermetauscher) grosser Solaranlagen entwickelt. Hierzu wurde eine der Aufgabenstellung angepasste Messtechnik entwickelt (Mobile meteorologische Datenerfassung mit Funkbetrieb, nicht-invasive Oberflaechen-Temperaturfuehler und Ultraschall-Volumenstrommessgeraete). Der Kollektorkreis einer grossen Solaranlage aus dem Programm Solarthermie 2000 wurde dynamisch ueber 11 Tage (29.10.-8.11.1997) mit der neuen Messtechnik vermessen. Zur Entwicklung eines geeigneten Auswerteverfahrens wurde die Anlage simulatorisch abgebildet und der Einfluss verschiedener Modellansaetze und der Betriebsbedingungen waehrend des Mess- und Vorhersagezeitraums auf die Vorhersageguete im Detail untersucht. Mit dem entwickelten Verfahren konnte aus der dynamischen Kurzzeitvermessung der in einer Langzeitmessung der ZfS Hilden ueber 7 Monate ermittelte Kollektorertrag nach dem solaren Waermetauscher auf deutlich besser als 5

  17. Dynamic Ocean Track System Plus -

    Data.gov (United States)

    Department of Transportation — Dynamic Ocean Track System Plus (DOTS Plus) is a planning tool implemented at the ZOA, ZAN, and ZNY ARTCCs. It is utilized by Traffic Management Unit (TMU) personnel...

  18. Dynamical systems and linear algebra

    OpenAIRE

    Colonius, Fritz (Prof.)

    2007-01-01

    Dynamical systems and linear algebra / F. Colonius, W. Kliemann. - In: Handbook of linear algebra / ed. by Leslie Hogben. - Boca Raton : Chapman & Hall/CRC, 2007. - S. 56,1-56,22. - (Discrete mathematics and its applications)

  19. Vehicle brake testing system

    Science.gov (United States)

    Stevens, Samuel S [Harriman, TN; Hodgson, Jeffrey W [Lenoir City, TN

    2002-11-19

    This invention relates to a force measuring system capable of measuring forces associated with vehicle braking and of evaluating braking performance. The disclosure concerns an invention which comprises a first row of linearly aligned plates, a force bearing surface extending beneath and beside the plates, vertically oriented links and horizontally oriented links connecting each plate to a force bearing surface, a force measuring device in each link, a transducer coupled to each force measuring device, and a computing device coupled to receive an output signal from the transducer indicative of measured force in each force measuring device. The present invention may be used for testing vehicle brake systems.

  20. Equivariant Dynamical Systems

    Directory of Open Access Journals (Sweden)

    Z. Ertinger

    1995-09-01

    Full Text Available Our aim is to present some aspects of the mathematical theory of strange behaviour of nonlinear systems, especially of systems with symmetry. Proofs are emitted, the interested reader is advised to references. Our presentation is inevitably selective. We focus on parts of the theory with possible applications to electronic circuits and systems which may display chaotic behaviour.

  1. Dynamical systems in population biology

    CERN Document Server

    Zhao, Xiao-Qiang

    2017-01-01

    This research monograph provides an introduction to the theory of nonautonomous semiflows with applications to population dynamics. It develops dynamical system approaches to various evolutionary equations such as difference, ordinary, functional, and partial differential equations, and pays more attention to periodic and almost periodic phenomena. The presentation includes persistence theory, monotone dynamics, periodic and almost periodic semiflows, basic reproduction ratios, traveling waves, and global analysis of prototypical population models in ecology and epidemiology. Research mathematicians working with nonlinear dynamics, particularly those interested in applications to biology, will find this book useful. It may also be used as a textbook or as supplementary reading for a graduate special topics course on the theory and applications of dynamical systems. Dr. Xiao-Qiang Zhao is a University Research Professor at Memorial University of Newfoundland, Canada. His main research interests involve applied...

  2. Tests of the Attachment and Developmental Dynamic Systems Theory of Crime (ADDSTOC): Toward a Differential RDoC Diagnostic and Treatment Approach.

    Science.gov (United States)

    Lindberg, Marc A; Zeid, Dana

    2018-01-01

    The Attachment and Developmental Dynamic Systems Theory of Crime was tested on 206 male inmates. They completed measures tapping attachments, clinical issues, adverse childhood events, peer crime, and crime addictions. A significant path model was found, going from insecure parental attachments to adverse childhood events, and then on to the behavioral crime addiction and criminal peers scales. Peer crime was also predicted by insecure parent attachments and the crime addiction scale. Finally, the crime addiction, peer crime, and insecure parental attachment scales predicted frequencies of criminal behavior. The model also fit a sample of 239 female inmates. The notions of crime addiction, in this context of adverse events and insecure parental attachments, offered newer and more powerful explanations than previously offered by social learning theories on why some individuals are more likely to associate with peers engaging in criminal behavior, and also how these combine to predict degrees of criminal behavior. By moving beyond main effects models, it was found that a focus on systems of interactions was robust in theory and application. However, profile data from the Attachment and Clinical Issues Questionnaire showed that individual differences in Research Domain Criteria diagnoses are fundamental to treatment settings. Such approaches to reducing rates of recidivism and substance abuse should also enhance outcomes in many domains, including HIV prevention, costs to health care, and at the same time increase overall public safety.

  3. Simulator testing system (STS)

    International Nuclear Information System (INIS)

    Miller, V.N.

    1990-01-01

    In recent years there has been a greater demand placed on the capabilities and time usage of real-time nuclear plant simulators due to NRC, INPO and utilities requirements. The requirements applied to certification, new simulators, upgrades, modifications, and maintenance of the simulators vary; however, they all require the capabilities of the simulator to be tested whether it is for NRC 10CFR55.45b requirements, ATP testing of new simulators, ATP testing of upgrades with or without panels, adding software/hardware due to plant modifications, or analyzing software/hardware problems on the simulator. This paper describes the Simulator Testing System (STS) which addresses each one of these requirements placed on simulators. Special attention will be given to ATP testing of upgrades without the use of control room panels. The capabilities and applications of the four parts of STS which are the Display Control Software (DCS), Procedure Control Software (PCS), Display Generator Software (DGS) and the Procedure Generator Software (PGS) will be reviewed

  4. Dynamic tests at the Outardes 3 dam

    International Nuclear Information System (INIS)

    Proulx, J.; Paultre, P.; Duron, Z.; Tai Mai Phat; Im, O.

    1992-01-01

    At the Outardes 3 gravity dam, part of the Manicouagan-Outardes hydroelectric complex in northeastern Quebec, forced vibration tests were carried out using an eccentric mass shaker attached to the dam crest at three different locations. Accelerations were measured along the crest and in the inspection galleries, and hydrodynamic pressures were measured along the upstream dam face and at various locations in the reservoir. The tests were designed to analyze the effects of gravity dam-reservoir interactions and to generate a data base for calibrating finite element models used in studying the dynamic behavior of gravity dams. Experimental results are presented in order to demonstrate the quality of the data obtained and the effectiveness of the experimental procedures. Modes of vibration were observed which corresponded to those obtained by finite element analysis. It is shown that techniques recently developed for dynamic tests on large dams can be successfully used on gravity dams. 3 refs., 6 figs

  5. Dynamic fracture toughness testing of structural steels

    International Nuclear Information System (INIS)

    Debel, C.P.

    1978-01-01

    Two candidate test methods aimed at producing materials properties of interest in connection with crack arrest assessments are currently under evaluation. These methods and the significance of the results are described. The quasi-static as well as the dynamic fracture toughness of a plain C-Mn steel in the as-quenched and tempered condition have been examined at temperatures between -115 0 C and the ambient temperature. Wedge-loaded duplex DCB-specimens were used in dynamic tests. The crack extension velocity was measured using a surface deposited grid and a registration circuit based on TTL-electronics. The toughness transition-temperature at quasi-static loading rate is found to be low; but during dynamic crack-extension a substantial shift of the transition-region to higher temperatures is produced, and fast fracture was obtained even at ambient temperature. Even though the dynamic fracture toughness Ksub(ID) increases with temperature, it decreases with increasing crack-extension velocity at a given temperature and the rate of decrease with respect to crack-extension velocity seems to be independent of temperature. Ksub(ID) appears to be insensitive to heat treatments. Test results indicate insufficient load-train stiffness, and problems due to crack branching were encountered. (author)

  6. Nightly Test system migration

    CERN Document Server

    Win-Lime, Kevin

    2013-01-01

    The summer student program allows students to participate to the Cern adventure. They can follow several interesting lectures about particle science and participate to the experiment work. As a summer student, I had worked for LHCb experiment. LHCb uses a lot of software to analyze its data. All this software is organized in packages and projects. They are built and tested during the night using an automated system and the results are displayed on a web interface. Actually, LHCb is changing this system. It is looking for a replacement candidate. So I was charged to unify some internal interfaces to permit a swift migration. In this document, I will describe shortly the system used by LHCb, then I will explain what I have done in detail.

  7. Testing of dynamic multileaf collimator by dynamic log file

    International Nuclear Information System (INIS)

    Ono, Kaoru; Nakamura, Tetsuji; Yamato, Shinichirou; Miyazawa, Masanori

    2007-01-01

    Intensity-modulated radiation therapy (IMRT) represents one of the most significant technical advances in radiation therapy. In the dynamic multileaf collimator (MLC) method of IMRT delivery, because of the relatively small gaps between opposed leaves and because most regions are shielded by leaves most of the time, the delivered dose is very sensitive to MLC leaf positional accuracy. A variation of ±0.2 mm in the gap width can result in a dose variation of ±3% for each clinical dynamic MLC field. Most often the effects of leaf motion are inferred from dose deviations on film or from variations in ionization measurements. These techniques provide dosimetric information but do not provide detailed information for diagnosing delivery problems. Therefore, a dynamic log file (Dynalog file) was used to verify dynamic MLC leaf positional accuracy. Measuring for narrow gaps using the thickness gauge could detect a log file accuracy of approximately 0.1 mm. The accuracy of dynamic MLC delivery depends on the accuracy with which the velocity of each leaf is controlled. We studied the relationship between leaf positional accuracy and leaf velocity. Leaf velocity of 0.7 cm/sec caused approximately 0.2 mm leaf positional variation. We then analyzed leaf positional accuracy for the clinical dynamic MLC field using Dynalog File Viewer (Varian Medical Systems, Inc., Palo Alto, California (CA)), and developed a new program that can analyze more detailed leaf motions. Using this program, we can obtain more detailed information, and therefore can determine the source of dose uncertainties for the dynamic MLC field. (author)

  8. Dynamics of Financial System: A System Dynamics Approach

    OpenAIRE

    Girish K. Nair; Lewlyn Lester Raj Rodrigues

    2013-01-01

    There are several ratios which define the financial health of an organization but the importance of Net cash flow, Gross income, Net income, Pending bills, Receivable bills, Debt, and Book value can never be undermined as they give the exact picture of the financial condition. While there are several approaches to study the dynamics of these variables, system dynamics based modelling and simulation is one of the modern techniques. The paper explores this method to simulate the before mentione...

  9. Self-supervised dynamical systems

    International Nuclear Information System (INIS)

    Zak, Michail

    2004-01-01

    A new type of dynamical systems which capture the interactions via information flows typical for active multi-agent systems is introduced. The mathematical formalism is based upon coupling the classical dynamical system (with random components caused by uncertainties in initial conditions as well as by Langevin forces) with the corresponding Liouville or the Fokker-Planck equations describing evolution of these uncertainties in terms of probability density. The coupling is implemented by information-based supervising forces which fundamentally change the patterns of probability evolution. It is demonstrated that the probability density can approach prescribed attractors while exhibiting such patterns as shock waves, solitons and chaos in probability space. Applications of these phenomena to information-based neural nets, expectation-based cooperation, self-programmed systems, control chaos using terminal attractors as well as to games with incomplete information, are addressed. A formal similarity between the mathematical structure of the introduced dynamical systems and quantum mechanics is discussed

  10. Tritium Systems Test Facility

    International Nuclear Information System (INIS)

    Cafasso, F.A.; Maroni, V.A.; Smith, W.H.; Wilkes, W.R.; Wittenberg, L.J.

    1978-01-01

    This TSTF proposal has two principal objectives. The first objective is to provide by mid-FY 1981 a demonstration of the fuel cycle and tritium containment systems which could be used in a Tokamak Experimental Power Reactor for operation in the mid-1980's. The second objective is to provide a capability for further optimization of tritium fuel cycle and environmental control systems beyond that which is required for the EPR. The scale and flow rates in TSTF are close to those which have been projected for a prototype experimental power reactor (PEPR/ITR) and will permit reliable extrapolation to the conditions found in an EPR. The fuel concentrations will be the same as in an EPR. Demonstrations of individual components of the deuterium-tritium fuel cycle and of monitoring, accountability and containment systems and of a maintenance methodology will be achieved at various times in the FY 1979-80 time span. Subsequent to the individual component demonstrations--which will proceed from tests with hydrogen (and/or deuterium) through tracer levels of tritium to full operational concentrations--a complete test and demonstration of the integrated fuel processing and tritium containment facility will be performed. This will occur near the middle of FY 1981. Two options were considered for the TSTF: (1) The modification of an existing building and (2) the construction of a new facility

  11. Nonlinear dynamics in biological systems

    CERN Document Server

    Carballido-Landeira, Jorge

    2016-01-01

    This book presents recent research results relating to applications of nonlinear dynamics, focusing specifically on four topics of wide interest: heart dynamics, DNA/RNA, cell mobility, and proteins. The book derives from the First BCAM Workshop on Nonlinear Dynamics in Biological Systems, held in June 2014 at the Basque Center of Applied Mathematics (BCAM). At this international meeting, researchers from different but complementary backgrounds, including molecular dynamics, physical chemistry, bio-informatics and biophysics, presented their most recent results and discussed the future direction of their studies using theoretical, mathematical modeling and experimental approaches. Such was the level of interest stimulated that the decision was taken to produce this publication, with the organizers of the event acting as editors. All of the contributing authors are researchers working on diverse biological problems that can be approached using nonlinear dynamics. The book will appeal especially to applied math...

  12. Power functional theory for the dynamic test particle limit

    International Nuclear Information System (INIS)

    Brader, Joseph M; Schmidt, Matthias

    2015-01-01

    For classical Brownian systems both in and out of equilibrium we extend the power functional formalism of Schmidt and Brader (2013 J. Chem. Phys. 138 214101) to mixtures of different types of particles. We apply the framework to develop an exact dynamical test particle theory for the self and distinct parts of the van Hove function, which characterize tagged and collective particle motion. The memory functions that induce non-Markovian dynamics are related to functional derivatives of the excess (over ideal) free power dissipation functional. The method offers an alternative to the recently found nonequilibrium Ornstein–Zernike relation for dynamic pair correlation functions. (paper)

  13. Dynamic Stability of Maglev Systems,

    Science.gov (United States)

    1992-04-01

    AD-A259 178 ANL-92/21 Materials and Components Dynamic Stability of Technology Division Materials and Components Maglev Systems Technology Division...of Maglev Systems Y. Cai, S. S. Chen, and T. M. Mulcahy Materials and Components Technology Division D. M. Rote Center for Transportation Research...of Maglev System with L-Shaped Guideway ......................................... 6 3 Stability of M aglev System s

  14. Resonance test system

    Science.gov (United States)

    Musial, Walter [Boulder, CO; White, Darris [Superior, CO

    2011-05-31

    An apparatus (10) for applying at least one load to a specimen (12) according to one embodiment of the invention may comprise a mass (18). An actuator (20) mounted to the specimen (12) and operatively associated with the mass (18) moves the mass (18) along a linear displacement path (22) that is perpendicular to a longitudinal axis of the specimen (12). A control system (26) operatively associated with the actuator (20) operates the actuator (20) to reciprocate the mass (18) along the linear displacement path (22) at a reciprocating frequency, the reciprocating frequency being about equal to a resonance frequency of the specimen (12) in a test configuration.

  15. Self-Supervised Dynamical Systems

    Science.gov (United States)

    Zak, Michail

    2003-01-01

    Some progress has been made in a continuing effort to develop mathematical models of the behaviors of multi-agent systems known in biology, economics, and sociology (e.g., systems ranging from single or a few biomolecules to many interacting higher organisms). Living systems can be characterized by nonlinear evolution of probability distributions over different possible choices of the next steps in their motions. One of the main challenges in mathematical modeling of living systems is to distinguish between random walks of purely physical origin (for instance, Brownian motions) and those of biological origin. Following a line of reasoning from prior research, it has been assumed, in the present development, that a biological random walk can be represented by a nonlinear mathematical model that represents coupled mental and motor dynamics incorporating the psychological concept of reflection or self-image. The nonlinear dynamics impart the lifelike ability to behave in ways and to exhibit patterns that depart from thermodynamic equilibrium. Reflection or self-image has traditionally been recognized as a basic element of intelligence. The nonlinear mathematical models of the present development are denoted self-supervised dynamical systems. They include (1) equations of classical dynamics, including random components caused by uncertainties in initial conditions and by Langevin forces, coupled with (2) the corresponding Liouville or Fokker-Planck equations that describe the evolutions of probability densities that represent the uncertainties. The coupling is effected by fictitious information-based forces, denoted supervising forces, composed of probability densities and functionals thereof. The equations of classical mechanics represent motor dynamics that is, dynamics in the traditional sense, signifying Newton s equations of motion. The evolution of the probability densities represents mental dynamics or self-image. Then the interaction between the physical and

  16. Dynamically reconfigurable photovoltaic system

    Science.gov (United States)

    Okandan, Murat; Nielson, Gregory N.

    2016-05-31

    A PV system composed of sub-arrays, each having a group of PV cells that are electrically connected to each other. A power management circuit for each sub-array has a communications interface and serves to connect or disconnect the sub-array to a programmable power grid. The power grid has bus rows and bus columns. A bus management circuit is positioned at a respective junction of a bus column and a bus row and is programmable through its communication interface to connect or disconnect a power path in the grid. As a result, selected sub-arrays are connected by selected power paths to be in parallel so as to produce a low system voltage, and, alternately in series so as to produce a high system voltage that is greater than the low voltage by at least a factor of ten.

  17. Dynamically reconfigurable photovoltaic system

    Energy Technology Data Exchange (ETDEWEB)

    Okandan, Murat; Nielson, Gregory N.

    2016-12-27

    A PV system composed of sub-arrays, each having a group of PV cells that are electrically connected to each other. A power management circuit for each sub-array has a communications interface and serves to connect or disconnect the sub-array to a programmable power grid. The power grid has bus rows and bus columns. A bus management circuit is positioned at a respective junction of a bus column and a bus row and is programmable through its communication interface to connect or disconnect a power path in the grid. As a result, selected sub-arrays are connected by selected power paths to be in parallel so as to produce a low system voltage, and, alternately in series so as to produce a high system voltage that is greater than the low voltage by at least a factor of ten.

  18. Dynamic probabilistic systems

    CERN Document Server

    Howard, Ronald A

    2007-01-01

    This book is an integrated work published in two volumes. The first volume treats the basic Markov process and its variants; the second, semi-Markov and decision processes. Its intent is to equip readers to formulate, analyze, and evaluate simple and advanced Markov models of systems, ranging from genetics and space engineering to marketing. More than a collection of techniques, it constitutes a guide to the consistent application of the fundamental principles of probability and linear system theory.Author Ronald A. Howard, Professor of Management Science and Engineering at Stanford University

  19. Dynamical system approach to phyllotaxis

    DEFF Research Database (Denmark)

    D'ovidio, Francesco; Mosekilde, Erik

    2000-01-01

    and not a dynamical system, mainly because new active elements are added at each step, and thus the dimension of the "natural" phase space is not conserved. Here a construction is presented by which a well defined dynamical system can be obtained, and a bifurcation analysis can be carried out. Stable and unstable...... of the Jacobian, and thus the eigenvalues, is given. It is likely that problems of the above type often arise in biology, and especially in morphogenesis, where growing systems are modeled....

  20. Constraint elimination in dynamical systems

    Science.gov (United States)

    Singh, R. P.; Likins, P. W.

    1989-01-01

    Large space structures (LSSs) and other dynamical systems of current interest are often extremely complex assemblies of rigid and flexible bodies subjected to kinematical constraints. A formulation is presented for the governing equations of constrained multibody systems via the application of singular value decomposition (SVD). The resulting equations of motion are shown to be of minimum dimension.

  1. Experimental Modeling of Dynamic Systems

    DEFF Research Database (Denmark)

    Knudsen, Morten Haack

    2006-01-01

    An engineering course, Simulation and Experimental Modeling, has been developed that is based on a method for direct estimation of physical parameters in dynamic systems. Compared with classical system identification, the method appears to be easier to understand, apply, and combine with physical...

  2. Computable Types for Dynamic Systems

    NARCIS (Netherlands)

    P.J. Collins (Pieter); K. Ambos-Spies; B. Loewe; W. Merkle

    2009-01-01

    textabstractIn this paper, we develop a theory of computable types suitable for the study of dynamic systems in discrete and continuous time. The theory uses type-two effectivity as the underlying computational model, but we quickly develop a type system which can be manipulated abstractly, but for

  3. Managing Complex Dynamical Systems

    Science.gov (United States)

    Cox, John C.; Webster, Robert L.; Curry, Jeanie A.; Hammond, Kevin L.

    2011-01-01

    Management commonly engages in a variety of research designed to provide insight into the motivation and relationships of individuals, departments, organizations, etc. This paper demonstrates how the application of concepts associated with the analysis of complex systems applied to such data sets can yield enhanced insights for managerial action.

  4. Parametric Resonance in Dynamical Systems

    CERN Document Server

    Nijmeijer, Henk

    2012-01-01

    Parametric Resonance in Dynamical Systems discusses the phenomenon of parametric resonance and its occurrence in mechanical systems,vehicles, motorcycles, aircraft and marine craft, and micro-electro-mechanical systems. The contributors provide an introduction to the root causes of this phenomenon and its mathematical equivalent, the Mathieu-Hill equation. Also included is a discussion of how parametric resonance occurs on ships and offshore systems and its frequency in mechanical and electrical systems. This book also: Presents the theory and principles behind parametric resonance Provides a unique collection of the different fields where parametric resonance appears including ships and offshore structures, automotive vehicles and mechanical systems Discusses ways to combat, cope with and prevent parametric resonance including passive design measures and active control methods Parametric Resonance in Dynamical Systems is ideal for researchers and mechanical engineers working in application fields such as MEM...

  5. The Finite Deformation Dynamic Sphere Test Problem

    Energy Technology Data Exchange (ETDEWEB)

    Versino, Daniele [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brock, Jerry Steven [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-02

    In this manuscript we describe test cases for the dynamic sphere problem in presence of finite deformations. The spherical shell in exam is made of a homogeneous, isotropic or transverse isotropic material and elastic and elastic-plastic material behaviors are considered. Twenty cases, (a) to (t), are thus defined combining material types and boundary conditions. The inner surface radius, the outer surface radius and the material's density are kept constant for all the considered test cases and their values are ri = 10mm, ro = 20mm and p = 1000Kg/m3 respectively.

  6. SPECTR System Operational Test Report

    International Nuclear Information System (INIS)

    Landman, W.H. Jr.

    2011-01-01

    This report overviews installation of the Small Pressure Cycling Test Rig (SPECTR) and documents the system operational testing performed to demonstrate that it meets the requirements for operations. The system operational testing involved operation of the furnace system to the design conditions and demonstration of the test article gas supply system using a simulated test article. The furnace and test article systems were demonstrated to meet the design requirements for the Next Generation Nuclear Plant. Therefore, the system is deemed acceptable and is ready for actual test article testing.

  7. The Dynamical Invariant of Open Quantum System

    OpenAIRE

    Wu, S. L.; Zhang, X. Y.; Yi, X. X.

    2015-01-01

    The dynamical invariant, whose expectation value is constant, is generalized to open quantum system. The evolution equation of dynamical invariant (the dynamical invariant condition) is presented for Markovian dynamics. Different with the dynamical invariant for the closed quantum system, the evolution of the dynamical invariant for the open quantum system is no longer unitary, and the eigenvalues of it are time-dependent. Since any hermitian operator fulfilling dynamical invariant condition ...

  8. Dynamic simulation of LMFBR systems

    International Nuclear Information System (INIS)

    Agrawal, A.K.; Khatib-Rahbar, M.

    1980-01-01

    This review article focuses on the dynamic analysis of liquid-metal-cooled fast breeder reactor systems in the context of protected transients. Following a brief discussion on various design and simulation approaches, a critical review of various models for in-reactor components, intermediate heat exchangers, heat transport systems and the steam generating system is presented. A brief discussion on choice of fuels as well as core and blanket system designs is also included. Numerical considerations for obtaining system-wide steady-state and transient solutions are discussed, and examples of various system transients are presented. Another area of major interest is verification of phenomenological models. Various steps involved in the code and model verification are briefly outlined. The review concludes by posing some further areas of interest in fast reactor dynamics and safety. (author)

  9. Combinations of complex dynamical systems

    CERN Document Server

    Pilgrim, Kevin M

    2003-01-01

    This work is a research-level monograph whose goal is to develop a general combination, decomposition, and structure theory for branched coverings of the two-sphere to itself, regarded as the combinatorial and topological objects which arise in the classification of certain holomorphic dynamical systems on the Riemann sphere. It is intended for researchers interested in the classification of those complex one-dimensional dynamical systems which are in some loose sense tame. The program is motivated by the dictionary between the theories of iterated rational maps and Kleinian groups.

  10. Coherent structures and dynamical systems

    Science.gov (United States)

    Jimenez, Javier

    1987-01-01

    Any flow of a viscous fluid has a finite number of degrees of freedom, and can therefore be seen as a dynamical system. A coherent structure can be thought of as a lower dimensional manifold in whose neighborhood the dynamical system spends a substantial fraction of its time. If such a manifold exists, and if its dimensionality is substantially lower that that of the full flow, it is conceivable that the flow could be described in terms of the reduced set of degrees of freedom, and that such a description would be simpler than one in which the existence of structure was not recognized. Several examples are briefly summarized.

  11. Energy Systems Test Area (ESTA). Power Systems Test Facilities

    Science.gov (United States)

    Situ, Cindy H.

    2010-01-01

    This viewgraph presentation provides a detailed description of the Johnson Space Center's Power Systems Facility located in the Energy Systems Test Area (ESTA). Facilities and the resources used to support power and battery systems testing are also shown. The contents include: 1) Power Testing; 2) Power Test Equipment Capabilities Summary; 3) Source/Load; 4) Battery Facilities; 5) Battery Test Equipment Capabilities Summary; 6) Battery Testing; 7) Performance Test Equipment; 8) Battery Test Environments; 9) Battery Abuse Chambers; 10) Battery Abuse Capabilities; and 11) Battery Test Area Resources.

  12. Truly random dynamics generated by autonomous dynamical systems

    Science.gov (United States)

    González, J. A.; Reyes, L. I.

    2001-09-01

    We investigate explicit functions that can produce truly random numbers. We use the analytical properties of the explicit functions to show that a certain class of autonomous dynamical systems can generate random dynamics. This dynamics presents fundamental differences with the known chaotic systems. We present real physical systems that can produce this kind of random time-series. Some applications are discussed.

  13. Dynamic decoupling of secondary systems

    International Nuclear Information System (INIS)

    Gupta, A.K.; Tembulkar, J.M.

    1984-01-01

    The dynamic analysis of primary systems must often be performed decoupled from the secondary system. In doing so, one should assure that the decoupling does not significantly affect the frequencies and the response of the primary systems. The practice consists of heuristic algorithms intended to limit changes in the frequencies. The change in response is not considered. In this paper, changes in both the frequencies and the response are considered. Rational, but simple algorithms are derived to make accurate predictions. Material up to MDOF primary-SDOF secondary system is presented in this paper. MDOF-MDOF systems are treated in a companion paper. (orig.)

  14. Dynamic Properties of Impulse Measuring Systems

    DEFF Research Database (Denmark)

    Pedersen, A.; Lausen, P.

    1971-01-01

    After some basic considerations the dynamic properties of the measuring system are subjected to a general examination based on a number of responses, characteristic of the system. It is demonstrated that an impulse circuit has an internal impedance different from zero, for which reason...... the interaction between the generator and the measuring circuit is of paramount importance to the voltage across the test object. Based on the measured values the determination of the applied voltage is considered....

  15. Dynamics of Variable Mass Systems

    Science.gov (United States)

    Eke, Fidelis O.

    1998-01-01

    This report presents the results of an investigation of the effects of mass loss on the attitude behavior of spinning bodies in flight. The principal goal is to determine whether there are circumstances under which the motion of variable mass systems can become unstable in the sense that their transverse angular velocities become unbounded. Obviously, results from a study of this kind would find immediate application in the aerospace field. The first part of this study features a complete and mathematically rigorous derivation of a set of equations that govern both the translational and rotational motions of general variable mass systems. The remainder of the study is then devoted to the application of the equations obtained to a systematic investigation of the effect of various mass loss scenarios on the dynamics of increasingly complex models of variable mass systems. It is found that mass loss can have a major impact on the dynamics of mechanical systems, including a possible change in the systems stability picture. Factors such as nozzle geometry, combustion chamber geometry, propellant's initial shape, size and relative mass, and propellant location can all have important influences on the system's dynamic behavior. The relative importance of these parameters on-system motion are quantified in a way that is useful for design purposes.

  16. Space Launch System Scale Model Acoustic Test Ignition Overpressure Testing

    Science.gov (United States)

    Nance, Donald; Liever, Peter; Nielsen, Tanner

    2015-01-01

    The overpressure phenomenon is a transient fluid dynamic event occurring during rocket propulsion system ignition. This phenomenon results from fluid compression of the accelerating plume gas, subsequent rarefaction, and subsequent propagation from the exhaust trench and duct holes. The high-amplitude unsteady fluid-dynamic perturbations can adversely affect the vehicle and surrounding structure. Commonly known as ignition overpressure (IOP), this is an important design-to environment for the Space Launch System (SLS) that NASA is currently developing. Subscale testing is useful in validating and verifying the IOP environment. This was one of the objectives of the Scale Model Acoustic Test, conducted at Marshall Space Flight Center. The test data quantifies the effectiveness of the SLS IOP suppression system and improves the analytical models used to predict the SLS IOP environments. The reduction and analysis of the data gathered during the SMAT IOP test series requires identification and characterization of multiple dynamic events and scaling of the event waveforms to provide the most accurate comparisons to determine the effectiveness of the IOP suppression systems. The identification and characterization of the overpressure events, the waveform scaling, the computation of the IOP suppression system knockdown factors, and preliminary comparisons to the analytical models are discussed.

  17. Space Launch System Scale Model Acoustic Test Ignition Overpressure Testing

    Science.gov (United States)

    Nance, Donald K.; Liever, Peter A.

    2015-01-01

    The overpressure phenomenon is a transient fluid dynamic event occurring during rocket propulsion system ignition. This phenomenon results from fluid compression of the accelerating plume gas, subsequent rarefaction, and subsequent propagation from the exhaust trench and duct holes. The high-amplitude unsteady fluid-dynamic perturbations can adversely affect the vehicle and surrounding structure. Commonly known as ignition overpressure (IOP), this is an important design-to environment for the Space Launch System (SLS) that NASA is currently developing. Subscale testing is useful in validating and verifying the IOP environment. This was one of the objectives of the Scale Model Acoustic Test (SMAT), conducted at Marshall Space Flight Center (MSFC). The test data quantifies the effectiveness of the SLS IOP suppression system and improves the analytical models used to predict the SLS IOP environments. The reduction and analysis of the data gathered during the SMAT IOP test series requires identification and characterization of multiple dynamic events and scaling of the event waveforms to provide the most accurate comparisons to determine the effectiveness of the IOP suppression systems. The identification and characterization of the overpressure events, the waveform scaling, the computation of the IOP suppression system knockdown factors, and preliminary comparisons to the analytical models are discussed.

  18. Non-smooth dynamical systems

    CERN Document Server

    2000-01-01

    The book provides a self-contained introduction to the mathematical theory of non-smooth dynamical problems, as they frequently arise from mechanical systems with friction and/or impacts. It is aimed at applied mathematicians, engineers, and applied scientists in general who wish to learn the subject.

  19. Controlling dynamics in diatomic systems

    Indian Academy of Sciences (India)

    WINTEC

    Abstract. Controlling molecular energetics using laser pulses is exemplified for nuclear motion in two different diatomic systems. The problem of finding the optimized field for maximizing a desired quantum dynamical target is formulated using an iterative method. The method is applied for two diatomic sys- tems, HF and OH.

  20. Ship Systems Survivability Test Site

    Data.gov (United States)

    Federal Laboratory Consortium — Area for testing survivability of shipboard systems to include electrical, communications, and fire suppression. Multipurpose test range for supporting gun firing,...

  1. Spent fuel's behavior under dynamic drip tests

    International Nuclear Information System (INIS)

    Finn, P.A.; Buck, E.C.; Hoh, J.C.; Bates, J.K.

    1995-01-01

    In the potential repository at Yucca Mountain, failure of the waste package container and the cladding of the spent nuclear fuel would expose the fuel to water under oxidizing conditions. To simulate the release behavior of radionuclides from spent fuel, dynamic drip and vapor tests with spent nuclear fuel have been ongoing for 2.5 years. Rapid alteration of the spent fuel has been noted with concurrent release of radionuclides. Colloidal species containing americium and plutonium have been found in the leachate. This observation suggests that colloidal transport of radionuclides should be included in the performance assessment of a potential repository

  2. Adaptive, dynamic, and resilient systems

    CERN Document Server

    Suri, Niranjan

    2015-01-01

    As the complexity of today's networked computer systems grows, they become increasingly difficult to understand, predict, and control. Addressing these challenges requires new approaches to building these systems. Adaptive, Dynamic, and Resilient Systems supplies readers with various perspectives of the critical infrastructure that systems of networked computers rely on. It introduces the key issues, describes their interrelationships, and presents new research in support of these areas.The book presents the insights of a different group of international experts in each chapter. Reporting on r

  3. Inspection system performance test procedure

    International Nuclear Information System (INIS)

    Jensen, C.E.

    1995-01-01

    This procedure establishes requirements to administer a performance demonstration test. The test is to demonstrate that the double-shell tank inspection system (DSTIS) supplied by the contractor performs in accordance with the WHC-S-4108, Double-Shell Tank Ultrasonic Inspection Performance Specification, Rev. 2-A, January, 1995. The inspection system is intended to provide ultrasonic (UT) and visual data to determine integrity of the Westinghouse Hanford Company (WHC) site underground waste tanks. The robotic inspection system consists of the following major sub-systems (modules) and components: Mobile control center; Deployment module; Cable management assembly; Robot mechanism; Ultrasonic testing system; Visual testing system; Pneumatic system; Electrical system; and Control system

  4. Operationalizing sustainability in urban coastal systems: a system dynamics analysis.

    Science.gov (United States)

    Mavrommati, Georgia; Bithas, Kostas; Panayiotidis, Panayiotis

    2013-12-15

    We propose a system dynamics approach for Ecologically Sustainable Development (ESD) in urban coastal systems. A systematic analysis based on theoretical considerations, policy analysis and experts' knowledge is followed in order to define the concept of ESD. The principles underlying ESD feed the development of a System Dynamics Model (SDM) that connects the pollutant loads produced by urban systems' socioeconomic activities with the ecological condition of the coastal ecosystem that it is delineated in operational terms through key biological elements defined by the EU Water Framework Directive. The receiving waters of the Athens Metropolitan area, which bears the elements of typical high population density Mediterranean coastal city but which currently has also new dynamics induced by the ongoing financial crisis, are used as an experimental system for testing a system dynamics approach to apply the concept of ESD. Systems' thinking is employed to represent the complex relationships among the components of the system. Interconnections and dependencies that determine the potentials for achieving ESD are revealed. The proposed system dynamics analysis can facilitate decision makers to define paths of development that comply with the principles of ESD. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Dynamical systems probabilistic risk assessment

    Energy Technology Data Exchange (ETDEWEB)

    Denman, Matthew R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ames, Arlo Leroy [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-03-01

    Probabilistic Risk Assessment (PRA) is the primary tool used to risk-inform nuclear power regulatory and licensing activities. Risk-informed regulations are intended to reduce inherent conservatism in regulatory metrics (e.g., allowable operating conditions and technical specifications) which are built into the regulatory framework by quantifying both the total risk profile as well as the change in the risk profile caused by an event or action (e.g., in-service inspection procedures or power uprates). Dynamical Systems (DS) analysis has been used to understand unintended time-dependent feedbacks in both industrial and organizational settings. In dynamical systems analysis, feedback loops can be characterized and studied as a function of time to describe the changes to the reliability of plant Structures, Systems and Components (SSCs). While DS has been used in many subject areas, some even within the PRA community, it has not been applied toward creating long-time horizon, dynamic PRAs (with time scales ranging between days and decades depending upon the analysis). Understanding slowly developing dynamic effects, such as wear-out, on SSC reliabilities may be instrumental in ensuring a safely and reliably operating nuclear fleet. Improving the estimation of a plant's continuously changing risk profile will allow for more meaningful risk insights, greater stakeholder confidence in risk insights, and increased operational flexibility.

  6. Standard test method for dynamic tear testing of metallic materials

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1983-01-01

    1.1 This test method covers the dynamic tear (DT) test using specimens that are 3/16 in. to 5/8 in. (5 mm to 16 mm) inclusive in thickness. 1.2 This test method is applicable to materials with a minimum thickness of 3/16 in. (5 mm). 1.3 The pressed-knife procedure described for sharpening the notch tip generally limits this test method to materials with a hardness level less than 36 HRC. Note 1—The designation 36 HRC is a Rockwell hardness number of 36 on Rockwell C scale as defined in Test Methods E 18. 1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  7. Dynamics of immune system vulnerabilities

    Science.gov (United States)

    Stromberg, Sean P.

    The adaptive immune system can be viewed as a complex system, which adapts, over time, to reflect the history of infections experienced by the organism. Understanding its operation requires viewing it in terms of tradeoffs under constraints and evolutionary history. It typically displays "robust, yet fragile" behavior, meaning common tasks are robust to small changes but novel threats or changes in environment can have dire consequences. In this dissertation we use mechanistic models to study several biological processes: the immune response, the homeostasis of cells in the lymphatic system, and the process that normally prevents autoreactive cells from entering the lymphatic system. Using these models we then study the effects of these processes interacting. We show that the mechanisms that regulate the numbers of cells in the immune system, in conjunction with the immune response, can act to suppress autoreactive cells from proliferating, thus showing quantitatively how pathogenic infections can suppress autoimmune disease. We also show that over long periods of time this same effect can thin the repertoire of cells that defend against novel threats, leading to an age correlated vulnerability. This vulnerability is shown to be a consequence of system dynamics, not due to degradation of immune system components with age. Finally, modeling a specific tolerance mechanism that normally prevents autoimmune disease, in conjunction with models of the immune response and homeostasis we look at the consequences of the immune system mistakenly incorporating pathogenic molecules into its tolerizing mechanisms. The signature of this dynamic matches closely that of the dengue virus system.

  8. Vehicle systems: coupled and interactive dynamics analysis

    Science.gov (United States)

    Vantsevich, Vladimir V.

    2014-11-01

    This article formulates a new direction in vehicle dynamics, described as coupled and interactive vehicle system dynamics. Formalised procedures and analysis of case studies are presented. An analytical consideration, which explains the physics of coupled system dynamics and its consequences for dynamics of a vehicle, is given for several sets of systems including: (i) driveline and suspension of a 6×6 truck, (ii) a brake mechanism and a limited slip differential of a drive axle and (iii) a 4×4 vehicle steering system and driveline system. The article introduces a formal procedure to turn coupled system dynamics into interactive dynamics of systems. A new research direction in interactive dynamics of an active steering and a hybrid-electric power transmitting unit is presented and analysed to control power distribution between the drive axles of a 4×4 vehicle. A control strategy integrates energy efficiency and lateral dynamics by decoupling dynamics of the two systems thus forming their interactive dynamics.

  9. Implementation of Keystroke Dynamics for Authentication in Computer Systems

    Directory of Open Access Journals (Sweden)

    S. V. Skuratov

    2010-06-01

    Full Text Available Implementation of keystroke dynamics in multifactor authentication systems is described in the article. Original access control system based on totality of matchers is presented. Testing results and useful recommendations are also adduced.

  10. Feedback coupling in dynamical systems

    Science.gov (United States)

    Trimper, Steffen; Zabrocki, Knud

    2003-05-01

    Different evolution models are considered with feedback-couplings. In particular, we study the Lotka-Volterra system under the influence of a cumulative term, the Ginzburg-Landau model with a convolution memory term and chemical rate equations with time delay. The memory leads to a modified dynamical behavior. In case of a positive coupling the generalized Lotka-Volterra system exhibits a maximum gain achieved after a finite time, but the population will die out in the long time limit. In the opposite case, the time evolution is terminated in a crash. Due to the nonlinear feedback coupling the two branches of a bistable model are controlled by the the strength and the sign of the memory. For a negative coupling the system is able to switch over between both branches of the stationary solution. The dynamics of the system is further controlled by the initial condition. The diffusion-limited reaction is likewise studied in case the reacting entities are not available simultaneously. Whereas for an external feedback the dynamics is altered, but the stationary solution remain unchanged, a self-organized internal feedback leads to a time persistent solution.

  11. Hidden attractors in dynamical systems

    Science.gov (United States)

    Dudkowski, Dawid; Jafari, Sajad; Kapitaniak, Tomasz; Kuznetsov, Nikolay V.; Leonov, Gennady A.; Prasad, Awadhesh

    2016-06-01

    Complex dynamical systems, ranging from the climate, ecosystems to financial markets and engineering applications typically have many coexisting attractors. This property of the system is called multistability. The final state, i.e., the attractor on which the multistable system evolves strongly depends on the initial conditions. Additionally, such systems are very sensitive towards noise and system parameters so a sudden shift to a contrasting regime may occur. To understand the dynamics of these systems one has to identify all possible attractors and their basins of attraction. Recently, it has been shown that multistability is connected with the occurrence of unpredictable attractors which have been called hidden attractors. The basins of attraction of the hidden attractors do not touch unstable fixed points (if exists) and are located far away from such points. Numerical localization of the hidden attractors is not straightforward since there are no transient processes leading to them from the neighborhoods of unstable fixed points and one has to use the special analytical-numerical procedures. From the viewpoint of applications, the identification of hidden attractors is the major issue. The knowledge about the emergence and properties of hidden attractors can increase the likelihood that the system will remain on the most desirable attractor and reduce the risk of the sudden jump to undesired behavior. We review the most representative examples of hidden attractors, discuss their theoretical properties and experimental observations. We also describe numerical methods which allow identification of the hidden attractors.

  12. Testing of Mortar Systems

    Science.gov (United States)

    2010-03-11

    IEP /TDP) or Independent Assessment Plan (IAP), and the test item and the procedures as outlined in this TOP. The following must also be considered...Command DTIC = Defense Technical Information Center DTP = Detailed Test Plan IAP = Independent Assessment Plan IEP = Independent Evaluation Plan IPT

  13. Full scale dynamic tests of Atucha II NPP

    International Nuclear Information System (INIS)

    Konno, T.; Alvarez, L.M.; Ceballos, M.A.; Prato, C.A.; Uchiyama, S.; Godoy, A.R.

    1995-01-01

    This paper summarizes the main results of a series of dynamic tests of the reactor building of Atucha II NPP performed to determine the dynamic properties of its massive structure deeply embedded in Quaternary soil deposits. Tests were performed under two different types of loading conditions: Steady state harmonic loads imposed by mechanical exciters and impulsive loads induced by dropping a weight on the ground surface in the vicinity. Natural frequencies and mode shapes were identified and the associated modal damping ratios were experimentally determined. Numerical analyses of the reactor building-foundation system by two different F.E. models were performed. One of them, based on an axisymmetric representation of the soil-structure system, was used to simulate the steady state vibration tests and to calculate the dynamic stiffness of the foundation slab and soil layers for comparison with those experimentally obtained. The other, a 3-D F.E. model of the superstructure, was used to assess the natural frequencies and mode shapes obtained from the tests, representing dynamic stiffness of the foundation with stiffness coefficients derived both from the tests and from the axisymmetric F.E. model. Good agreement of the natural frequencies given by two types of tests was generally found, with the largest difference between them in the fundamental frequency of the building. Estimates of modal damping derived from the tests showed significant differences depending on the technique used to calculate them. For the fundamental mode damping was found to be 23-42 %, gradually decreasing with frequency to 2-4 % for around 10 Hz. (author)

  14. Full scale dynamic tests of Atucha II NPP

    International Nuclear Information System (INIS)

    Prato, C.A.; Ceballos, M.A.; Konno, T.; Uchiyama, S.; Alvarez, L.M.; Godoy, A.R.

    1998-01-01

    This paper summarizes the main results of a series of dynamic tests of the reactor building of Atucha II NPP performed to determine the dynamic properties of its massive structure deeply embedded in quaternary soil deposits. Tests were performed under two different types of loading conditions: steady state harmonic loads imposed by mechanical exciters and impulsive loads induced by dropping a weight on the ground surface in the vicinity. Natural frequencies and mode shapes were identified and the associated modal damping ratios were experimentally determined. Numerical analyses of the reactor building-foundation system by two different F.E. models were performed. One of them, based on an axisymmetric representation of the soil-structure system, was used to simulate the steady state vibration tests and to calculate the dynamic stiffness of the foundation slab and soil layers for comparison with those experimentally obtained. The other, a 3-D F.E. model of the superstructure, was used to assess the natural frequencies and mode shapes obtained from the tests, representing dynamic stiffness of the foundation with stiffness coefficients derived both from the tests and from the axisymmetric F.E. model. Good agreement of the natural frequencies given by two types of tests were generally found, with the largest difference between them in the fundamental frequency of the building. Estimates of modal damping derived from the tests showed significant differences depending on the technique used to calculate them. For the fundamental mode, damping was found to be 23-42%, gradually decreasing with frequency to 2-4% for ∝10 Hz. (orig.)

  15. Dynamical Systems and Motion Vision.

    Science.gov (United States)

    1988-04-01

    TASK Artificial Inteligence Laboratory AREA I WORK UNIT NUMBERS 545 Technology Square . Cambridge, MA 02139 C\\ II. CONTROLLING OFFICE NAME ANO0 ADDRESS...INSTITUTE OF TECHNOLOGY ARTIFICIAL INTELLIGENCE LABORATORY A.I.Memo No. 1037 April, 1988 Dynamical Systems and Motion Vision Joachim Heel Abstract: In this... Artificial Intelligence L3 Laboratory of the Massachusetts Institute of Technology. Support for the Laboratory’s [1 Artificial Intelligence Research is

  16. DYNAMICS OF FINANCIAL SYSTEM: A SYSTEM DYNAMICS APPROACH

    Directory of Open Access Journals (Sweden)

    Girish K Nair

    2013-01-01

    Full Text Available There are several ratios which define the financial health of an organization but the importance of Net cash flow, Gross income, Net income, Pending bills, Receivable bills, Debt, and Book value can never be undermined as they give the exact picture of the financial condition. While there are several approaches to study the dynamics of these variables, system dynamics based modelling and simulation is one of the modern techniques. The paper explores this method to simulate the before mentioned parameters during production capacity expansion in an electronic industry. Debt and Book value have shown a non-linear pattern of variation which is discussed. The model can be used by the financial experts as a decision support tool in arriving at conclusions in connection to the expansion plans of the organization.

  17. Safety of high speed ground transportation systems: X2000 US demonstration vehicle dynamics trials, preliminary test report. Report for October 1992-January 1993

    Energy Technology Data Exchange (ETDEWEB)

    Whitten, B.T.; Kesler, J.K.

    1993-01-01

    The report documents the procedures, events, and results of vehicle dynamic tests carried out on the ASEA-Brown Boveri (ABB) X2000 tilt body trainset in the US between October 1992 and January 1993. These tests, sponsored by Amtrak and supported by the FRA, were conducted to assess the suitability of the X2000 trainset for safe operation at elevated cant deficiencies and speeds in Amtrak's Northeast Corridor under existing track conditions in a revenue service demonstration. The report describes the safety criteria against which the performance of the X2000 test train was examined, the instrumentation used, the test locations, and the track conditions. Preliminary results are presented from tests conducted on Amtrak lines between Philadelphia and Harrisburg, PA, and between Washington DC and New York NY, in which cant deficiencies of 12.5 inches and speeds of 154 mph were reached in a safe and controlled manner. The significance of the results is discussed, and preliminary conclusions and recommendations are presented.

  18. Dynamic Analysis and Test Results for an STC Stirling Generator

    Science.gov (United States)

    Qiu, Songgang; Peterson, Allen A.

    2004-02-01

    Long-life, high-efficiency generators based on free-piston Stirling machines are a future energy-conversion solution for both space and commercial applications. To aid in design and system integration efforts, Stirling Technology Company (STC) has developed dynamic simulation models for the internal moving subassemblies and for complete Stirling convertor assemblies. These dynamic models have been validated using test data from operating prototypes. Simplified versions of these models are presented to help explain the operating characteristics of the Stirling convertor. Power spectrum analysis is presented for the test data for casing acceleration, piston motion, displacer motion, and controller current/voltage during full power operation. The harmonics of a Stirling convertor and its moving components are identified for the STC zener-diode control scheme. The dynamic behavior of each moving component and its contribution to the system dynamics and resultant vibration forces are discussed. Additionally, the effects of a passive balancer and external suspension are predicted by another simplified system model.

  19. On Rank Driven Dynamical Systems

    Science.gov (United States)

    Veerman, J. J. P.; Prieto, F. J.

    2014-08-01

    We investigate a class of models related to the Bak-Sneppen (BS) model, initially proposed to study evolution. The BS model is extremely simple and yet captures some forms of "complex behavior" such as self-organized criticality that is often observed in physical and biological systems. In this model, random fitnesses in are associated to agents located at the vertices of a graph . Their fitnesses are ranked from worst (0) to best (1). At every time-step the agent with the worst fitness and some others with a priori given rank probabilities are replaced by new agents with random fitnesses. We consider two cases: The exogenous case where the new fitnesses are taken from an a priori fixed distribution, and the endogenous case where the new fitnesses are taken from the current distribution as it evolves. We approximate the dynamics by making a simplifying independence assumption. We use Order Statistics and Dynamical Systems to define a rank-driven dynamical system that approximates the evolution of the distribution of the fitnesses in these rank-driven models, as well as in the BS model. For this simplified model we can find the limiting marginal distribution as a function of the initial conditions. Agreement with experimental results of the BS model is excellent.

  20. Dynamic leaching test of personal computer components.

    Science.gov (United States)

    Li, Yadong; Richardson, Jay B; Niu, Xiaojun; Jackson, Ollie J; Laster, Jeremy D; Walker, Aaron K

    2009-11-15

    A dynamic leaching test (DLT) was developed and used to evaluate the leaching of toxic substances for electronic waste in the environment. The major components in personal computers (PCs) including motherboards, hard disc drives, floppy disc drives, and compact disc drives were tested. The tests lasted for 2 years for motherboards and 1.5 year for the disc drives. The extraction fluids for the standard toxicity characteristic leaching procedure (TCLP) and synthetic precipitation leaching procedure (SPLP) were used as the DLT leaching solutions. A total of 18 elements including Ag, Al, As, Au, Ba, Be, Cd, Cr, Cu, Fe, Ga, Ni, Pd, Pb, Sb, Se, Sn, and Zn were analyzed in the DLT leachates. Only Al, Cu, Fe, Ni, Pb, and Zn were commonly found in the DLT leachates of the PC components. Their leaching levels were much higher in TCLP extraction fluid than in SPLP extraction fluid. The toxic heavy metal Pb was found to continuously leach out of the components over the entire test periods. The cumulative amounts of Pb leached out of the motherboards in TCLP extraction fluid reached 2.0 g per motherboard over the 2-year test period, and that in SPLP extraction fluid were 75-90% less. The leaching rates or levels of Pb were largely affected by the content of galvanized steel in the PC components. The higher was the steel content, the lower the Pb leaching rate would be. The findings suggest that the obsolete PCs disposed of in landfills or discarded in the environment continuously release Pb for years when subjected to landfill leachate or rains.

  1. Testing particle filters on convective scale dynamics

    Science.gov (United States)

    Haslehner, Mylene; Craig, George. C.; Janjic, Tijana

    2014-05-01

    Particle filters have been developed in recent years to deal with highly nonlinear dynamics and non Gaussian error statistics that also characterize data assimilation on convective scales. In this work we explore the use of the efficient particle filter (P.v. Leeuwen, 2011) for convective scale data assimilation application. The method is tested in idealized setting, on two stochastic models. The models were designed to reproduce some of the properties of convection, for example the rapid development and decay of convective clouds. The first model is a simple one-dimensional, discrete state birth-death model of clouds (Craig and Würsch, 2012). For this model, the efficient particle filter that includes nudging the variables shows significant improvement compared to Ensemble Kalman Filter and Sequential Importance Resampling (SIR) particle filter. The success of the combination of nudging and resampling, measured as RMS error with respect to the 'true state', is proportional to the nudging intensity. Significantly, even a very weak nudging intensity brings notable improvement over SIR. The second model is a modified version of a stochastic shallow water model (Würsch and Craig 2013), which contains more realistic dynamical characteristics of convective scale phenomena. Using the efficient particle filter and different combination of observations of the three field variables (wind, water 'height' and rain) allows the particle filter to be evaluated in comparison to a regime where only nudging is used. Sensitivity to the properties of the model error covariance is also considered. Finally, criteria are identified under which the efficient particle filter outperforms nudging alone. References: Craig, G. C. and M. Würsch, 2012: The impact of localization and observation averaging for convective-scale data assimilation in a simple stochastic model. Q. J. R. Meteorol. Soc.,139, 515-523. Van Leeuwen, P. J., 2011: Efficient non-linear data assimilation in geophysical

  2. Dynamic characteristics of lead rubber bearings with dynamic two-dimensional test equipment

    International Nuclear Information System (INIS)

    Ohtori, Y.; Ishida, K.; Mazda, T.

    1994-01-01

    Although studies have previously been done on the static mechanical properties of lead rubber bearings, this study aims to grasp the dynamic characteristics of lead rubber bearings from experimental results, using two-dimensional dynamic test equipment which is designed to grasp in detail such dynamic characteristics as deformation capacity and proof stress. This paper describes the results from three types of tests: (1) dynamic mechanical properties tests, (2) cyclic loading tests, and (3) dynamic ultimate tests. Through these tests, it was confirmed that the dynamic characteristics of lead rubber bearings are independent of strain rate

  3. Mobile leak testing system

    International Nuclear Information System (INIS)

    Ungr, F.

    The design and implementation are described of a mobile testing unit ULTRATEST M for helium leak tests. The equipment has been developed by Leybold-Heraeus GmbH in Cologne and is in-built in a Mercedes-Benz 208 van. The equipment is designed for the operative use in assembly and construction of nuclear power plants and its throughput is sufficient for checking the whole upper reactor block. It may also be used for removing defects of vacuum equipment requiring a high level of tightness or equally demanding equipment used in the chemical industry. Experience with the equipment is described. (B.S.)

  4. CAMAC system test module

    International Nuclear Information System (INIS)

    Dawson, W.K.; Gjovig, A.; Naivar, F.; Potter, J.; Smith, W.

    1981-01-01

    Since the CAMAC Branch Highway is used to both send information to and receive information from a CAMAC crate, faults in this highway can be difficult to recognize and diagnose. Similarly faults caused by a Crate Controller corrupting either instructions or data are difficult to distinguish from faults caused by the modules themselves. The CLIVIT (CAMAC Logic Integrity Via Interactive Testing) module is designed to largely eliminate such difficulties and ambiguities by allowing the verification of Branch Highway and Dataway transactions via an independent data communication path. The principle of operation of the CLIVIT is explained. Described are the prototype construction, testing and use

  5. Test system and method

    DEFF Research Database (Denmark)

    2012-01-01

    at a second distance from the centre, the second distance being larger than the first distance, one or more sensors arranged at each fluid channel, wherein the sensors each comprise at least one optical detectable member, the test apparatus further comprising one or more optical sensing devices arranged...... larger than the first distance, one or more sensors arranged at each fluid channel, wherein the sensors each comprise at least one optical detectable member, the test apparatus further comprising one or more optical sensing devices arranged for sensing the at least one optical detectable member...

  6. Optical Fibres Contactless Sensor for Dynamic Testing of Lightweight Structures

    Directory of Open Access Journals (Sweden)

    L. Bregant

    2008-01-01

    Full Text Available With dynamic testing, engineers describe activities focused on the identification of some properties of vibrating structures. This step requires for the measurements of excitations and responses signals, applying appropriate sensors directly on the test article. These instruments modify the system's mass and stiffness distributions and eventually the eigen-properties of the structure. These errors become unacceptable especially when testing lightweight structures. This paper shows the results of some tests performed on a small compressor with the purpose of identifying the blades’ natural frequencies and modes. It compares the acquisitions performed with standard accelerometers and two different contact-less systems using as exciters either a micro-hammer or a micro inertial shaker. The paper shows how the contact-less sensors provide good quality data and consistent results in the mode identification phase.

  7. Substitution dynamical systems spectral analysis

    CERN Document Server

    Queffélec, Martine

    2010-01-01

    This volume mainly deals with the dynamics of finitely valued sequences, and more specifically, of sequences generated by substitutions and automata. Those sequences demonstrate fairly simple combinatorical and arithmetical properties and naturally appear in various domains. As the title suggests, the aim of the initial version of this book was the spectral study of the associated dynamical systems: the first chapters consisted in a detailed introduction to the mathematical notions involved, and the description of the spectral invariants followed in the closing chapters. This approach, combined with new material added to the new edition, results in a nearly self-contained book on the subject. New tools - which have also proven helpful in other contexts - had to be developed for this study. Moreover, its findings can be concretely applied, the method providing an algorithm to exhibit the spectral measures and the spectral multiplicity, as is demonstrated in several examples. Beyond this advanced analysis, many...

  8. System dynamics in hydropower plants

    Energy Technology Data Exchange (ETDEWEB)

    Stuksrud, Dag Birger

    1998-12-31

    The main purpose of this thesis on system dynamics in hydropower plants was to establish new models of a hydropower system where the turbine/conduits and the electricity supply and generation are connected together as one unit such that possible interactions between the two power regimes can be studied. In order to describe the system dynamics as well as possible, a previously developed analytic model of high-head Francis turbines is improved. The model includes the acceleration resistance in the turbine runner and the draft tube. Expressions for the loss coefficients in the model are derived in order to obtain a purely analytic model. The necessity of taking the hydraulic inertia into account is shown by means of simulations. Unstable behaviour and a higher transient turbine speed than expected may occur for turbines with steep characteristics or large draft tubes. The turbine model was verified previously with respect to a high-head Francis turbine; the thesis performs an experimental verification on a low-head Francis turbine and compares the measurements with simulations from the improved turbine model. It is found that the dynamic turbine model is, after adjustment, capable of describing low-head machines as well with satisfying results. The thesis applies a method called the ``Limited zero-pole method`` to obtain new rational approximations of the elastic behaviour in the conduits with frictional damping included. These approximations are used to provide an accurate state space formulation of a hydropower plant. Simulations performed with the new computer programs show that hydraulic transients such as water-hammer and mass oscillations are reflected in the electric grid. Unstable governing performance in the electric and hydraulic parts also interact. This emphasizes the need for analysing the whole power system as a unit. 63 refs., 149 figs., 4 tabs.

  9. Nuclear system test simulator

    International Nuclear Information System (INIS)

    Sawyer, S.D.; Hill, W.D.; Wilson, P.A.; Steiner, W.M.

    1987-01-01

    A transportable test simulator is described for a nuclear power plant. The nuclear power plant includes a control panel, a reactor having actuated rods for moving into and out of a reactor for causing the plant to operate, and a control rod network extending between the control panel and the reactor rods. The network serially transmits command words between the panel and rods, and has connecting interfaces at preselected points remote from the control panel between the control panel and rods. The test simulator comprises: a test simulator input for transport to and connection into the network at at least one interface for receiving the serial command words from the network. Each serial command includes an identifier portion and a command portion; means for processing interior of the simulator for the serial command words for identifying that portion of the power plant designated in the identifier portion and processing the word responsive to the command portion of the word after the identification; means for generating a response word responsive to the command portion; and output means for sending and transmitting the response word to the nuclear power plant at the interface whereby the control panel responds to the response word

  10. Cascade Distiller System Performance Testing Interim Results

    Science.gov (United States)

    Callahan, Michael R.; Pensinger, Stuart; Sargusingh, Miriam J.

    2014-01-01

    The Cascade Distillation System (CDS) is a rotary distillation system with potential for greater reliability and lower energy costs than existing distillation systems. Based upon the results of the 2009 distillation comparison test (DCT) and recommendations of the expert panel, the Advanced Exploration Systems (AES) Water Recovery Project (WRP) project advanced the technology by increasing reliability of the system through redesign of bearing assemblies and improved rotor dynamics. In addition, the project improved the CDS power efficiency by optimizing the thermoelectric heat pump (TeHP) and heat exchanger design. Testing at the NASA-JSC Advanced Exploration System Water Laboratory (AES Water Lab) using a prototype Cascade Distillation Subsystem (CDS) wastewater processor (Honeywell d International, Torrance, Calif.) with test support equipment and control system developed by Johnson Space Center was performed to evaluate performance of the system with the upgrades as compared to previous system performance. The system was challenged with Solution 1 from the NASA Exploration Life Support (ELS) distillation comparison testing performed in 2009. Solution 1 consisted of a mixed stream containing human-generated urine and humidity condensate. A secondary objective of this testing is to evaluate the performance of the CDS as compared to the state of the art Distillation Assembly (DA) used in the ISS Urine Processor Assembly (UPA). This was done by challenging the system with ISS analog waste streams. This paper details the results of the AES WRP CDS performance testing.

  11. Power system dynamics and control

    CERN Document Server

    Kwatny, Harry G

    2016-01-01

    This monograph explores a consistent modeling and analytic framework that provides the tools for an improved understanding of the behavior and the building of efficient models of power systems. It covers the essential concepts for the study of static and dynamic network stability, reviews the structure and design of basic voltage and load-frequency regulators, and offers an introduction to power system optimal control with reliability constraints. A set of Mathematica tutorial notebooks providing detailed solutions of the examples worked-out in the text, as well as a package that will enable readers to work out their own examples and problems, supplements the text. A key premise of the book is that the design of successful control systems requires a deep understanding of the processes to be controlled; as such, the technical discussion begins with a concise review of the physical foundations of electricity and magnetism. This is followed by an overview of nonlinear circuits that include resistors, inductors, ...

  12. Dynamic of small photovoltaic systems

    Science.gov (United States)

    Mehrmann, A.; Kleinkauf, W.; Pigorsch, W.; Steeb, H.

    The results of 1.5 yr of field-testing of two photovoltaic (PV) power plants, one equipped with an electrolyzer and H2 storage, are reported. Both systems were interconnected with the grid and featured the PV module, a power conditioning unit, ac and dc load connections, and control units. The rated power of both units was 100 Wp. The system with electrolysis was governed by control laws which maximized the electrolyzer current. The tests underscored the preference for a power conditioning unit, rather than direct output to load connections. A 1 kWp system was developed in a follow-up program and will be tested in concert with electrolysis and interconnection with several grid customers. The program is geared to eventual development of larger units for utility-size applications.

  13. Controlling Complex Systems and Developing Dynamic Technology

    Science.gov (United States)

    Avizienis, Audrius Victor

    In complex systems, control and understanding become intertwined. Following Ilya Prigogine, we define complex systems as having control parameters which mediate transitions between distinct modes of dynamical behavior. From this perspective, determining the nature of control parameters and demonstrating the associated dynamical phase transitions are practically equivalent and fundamental to engaging with complexity. In the first part of this work, a control parameter is determined for a non-equilibrium electrochemical system by studying a transition in the morphology of structures produced by an electroless deposition reaction. Specifically, changing the size of copper posts used as the substrate for growing metallic silver structures by the reduction of Ag+ from solution under diffusion-limited reaction conditions causes a dynamical phase transition in the crystal growth process. For Cu posts with edge lengths on the order of one micron, local forces promoting anisotropic growth predominate, and the reaction produces interconnected networks of Ag nanowires. As the post size is increased above 10 microns, the local interfacial growth reaction dynamics couple with the macroscopic diffusion field, leading to spatially propagating instabilities in the electrochemical potential which induce periodic branching during crystal growth, producing dendritic deposits. This result is interesting both as an example of control and understanding in a complex system, and as a useful combination of top-down lithography with bottom-up electrochemical self-assembly. The second part of this work focuses on the technological development of devices fabricated using this non-equilibrium electrochemical process, towards a goal of integrating a complex network as a dynamic functional component in a neuromorphic computing device. Self-assembled networks of silver nanowires were reacted with sulfur to produce interfacial "atomic switches": silver-silver sulfide junctions, which exhibit

  14. Nonlinear transport of dynamic system phase space

    International Nuclear Information System (INIS)

    Xie Xi; Xia Jiawen

    1993-01-01

    The inverse transform of any order solution of the differential equation of general nonlinear dynamic systems is derived, realizing theoretically the nonlinear transport for the phase space of nonlinear dynamic systems. The result is applicable to general nonlinear dynamic systems, with the transport of accelerator beam phase space as a typical example

  15. Musashi dynamic image processing system

    International Nuclear Information System (INIS)

    Murata, Yutaka; Mochiki, Koh-ichi; Taguchi, Akira

    1992-01-01

    In order to produce transmitted neutron dynamic images using neutron radiography, a real time system called Musashi dynamic image processing system (MDIPS) was developed to collect, process, display and record image data. The block diagram of the MDIPS is shown. The system consists of a highly sensitive, high resolution TV camera driven by a custom-made scanner, a TV camera deflection controller for optimal scanning, which adjusts to the luminous intensity and the moving speed of an object, a real-time corrector to perform the real time correction of dark current, shading distortion and field intensity fluctuation, a real time filter for increasing the image signal to noise ratio, a video recording unit and a pseudocolor monitor to realize recording in commercially available products and monitoring by means of the CRTs in standard TV scanning, respectively. The TV camera and the TV camera deflection controller utilized for producing still images can be applied to this case. The block diagram of the real-time corrector is shown. Its performance is explained. Linear filters and ranked order filters were developed. (K.I.)

  16. Quantum Dynamics in Biological Systems

    Science.gov (United States)

    Shim, Sangwoo

    In the first part of this dissertation, recent efforts to understand quantum mechanical effects in biological systems are discussed. Especially, long-lived quantum coherences observed during the electronic energy transfer process in the Fenna-Matthews-Olson complex at physiological condition are studied extensively using theories of open quantum systems. In addition to the usual master equation based approaches, the effect of the protein structure is investigated in atomistic detail through the combined application of quantum chemistry and molecular dynamics simulations. To evaluate the thermalized reduced density matrix, a path-integral Monte Carlo method with a novel importance sampling approach is developed for excitons coupled to an arbitrary phonon bath at a finite temperature. In the second part of the thesis, simulations of molecular systems and applications to vibrational spectra are discussed. First, the quantum dynamics of a molecule is simulated by combining semiclassical initial value representation and density funcitonal theory with analytic derivatives. A computationally-tractable approximation to the sum-of-states formalism of Raman spectra is subsequently discussed.

  17. On some dynamical chameleon systems

    Science.gov (United States)

    Burkin, I. M.; Kuznetsova, O. I.

    2018-03-01

    It is now well known that dynamical systems can be categorized into systems with self-excited attractors and systems with hidden attractors. A self-excited attractor has a basin of attraction that is associated with an unstable equilibrium, while a hidden attractor has a basin of attraction that does not intersect with small neighborhoods of any equilibrium points. Hidden attractors play the important role in engineering applications because they allow unexpected and potentially disastrous responses to perturbations in a structure like a bridge or an airplane wing. In addition, complex behaviors of chaotic systems have been applied in various areas from image watermarking, audio encryption scheme, asymmetric color pathological image encryption, chaotic masking communication to random number generator. Recently, researchers have discovered the so-called “chameleon systems”. These systems were so named because they demonstrate self-excited or hidden oscillations depending on the value of parameters. The present paper offers a simple algorithm of synthesizing one-parameter chameleon systems. The authors trace the evolution of Lyapunov exponents and the Kaplan-Yorke dimension of such systems which occur when parameters change.

  18. Portable Health Algorithms Test System

    Science.gov (United States)

    Melcher, Kevin J.; Wong, Edmond; Fulton, Christopher E.; Sowers, Thomas S.; Maul, William A.

    2010-01-01

    A document discusses the Portable Health Algorithms Test (PHALT) System, which has been designed as a means for evolving the maturity and credibility of algorithms developed to assess the health of aerospace systems. Comprising an integrated hardware-software environment, the PHALT system allows systems health management algorithms to be developed in a graphical programming environment, to be tested and refined using system simulation or test data playback, and to be evaluated in a real-time hardware-in-the-loop mode with a live test article. The integrated hardware and software development environment provides a seamless transition from algorithm development to real-time implementation. The portability of the hardware makes it quick and easy to transport between test facilities. This hard ware/software architecture is flexible enough to support a variety of diagnostic applications and test hardware, and the GUI-based rapid prototyping capability is sufficient to support development execution, and testing of custom diagnostic algorithms. The PHALT operating system supports execution of diagnostic algorithms under real-time constraints. PHALT can perform real-time capture and playback of test rig data with the ability to augment/ modify the data stream (e.g. inject simulated faults). It performs algorithm testing using a variety of data input sources, including real-time data acquisition, test data playback, and system simulations, and also provides system feedback to evaluate closed-loop diagnostic response and mitigation control.

  19. System Dynamics and Serious Games

    OpenAIRE

    Van Daalen, C.; Schaffernicht, M.; Mayer, I.

    2014-01-01

    This paper deals with the relationship between serious games and system dynamics. Games have been used in SD since the beginning. However, the field of serious gaming also has its own development. The purpose of this contribution is to provide a broad overview of the combination of serious gaming and SD and discuss the state of the art and promise. We first define serious game, simulation and case study and then point out how SD overlaps with them. Then we move on to define the basic componen...

  20. Dynamic-energetic balance of agricultural tractors: active systems for the measurement of the power requirements in static tests and under field conditions

    Directory of Open Access Journals (Sweden)

    Daniele Pochi

    2013-09-01

    Full Text Available Modern tractors are characterized by the introduction of devices designed to increase the operative performances of the machines, such as systems for monitoring and controlling various functions (through a massive use of electronics and hydraulics, or deputed to improve the comfort of the driver (paying more attention to ergonomics, air-conditioning, noise and vibration. Such devices need energy to be operated, affecting the energetic balance of the tractor. In this context, the availability of suitable methodologies and instrumental systems could be useful to provide objective, accurate and reliable measurements of the performances of the tractors under different conditions, also considering the power requirements from ancillary services and/or simulating the coupling with operating machines. The tests on the performances of tractors are now made using different methods, including the trial codes issued by the OECD Codes. Beyond their undoubted validity, they fix standard test conditions that often do not adequately represent the operative reality, so that, much remains to investigate on the actual performances provided by the tractors. From this point of view and with reference to fixed point tests, a test bench was developed for the measurement of the power required by various devices, such as transmission and air conditioning. It was used in experimental tests on a tracked tractor and on a wheeled tractor, aimed at validating the test device, measuring the power absorption related to the rotational speed of the organs of propulsion and to the characteristics curves, in order to quantify the power drawn by the transmission and by the air conditioning and assess the residual power for other tractor functions. As to field conditions, a study is being conducted at CRA-ING, within the project PTO (Mi.P.A.A.F., to develop a mobile test bench aimed at evaluating the power required by different operations, such as self displacement, traction, use of

  1. Dynamic stack testing and HiL simulation

    Energy Technology Data Exchange (ETDEWEB)

    Randolf, G. [GRandalytics, Honolulu, HI (United States)

    2009-07-01

    The applications for fuel cell and stack deployment have changed rapidly over the years, from stationary backup supplies to highly dynamic automotive power systems. As a result, testing must keep up in order to ensure mature products of high quality. A new breed of stack test stations has been designed, based on a newly developed single cell, high dynamic hardware-in-the-loop (HiL) simulator in order to meet the growing demand of realistic fuel cell testing scenarios for aviation and automotive industries. The paper described and illustrated the test station architecture and outline of communication nodes. The paper also described the voltage monitor and presented schematics of voltage monitoring modules. The basic requirements of the architecture that were presented included low latency; flexible communication with simulation targets and other data input/output nodes; scalability to various stack sizes; and, safety and reliability. It was concluded that first tests with the voltage monitoring system not only confirmed the design, high throughput and signal quality, but also suggested another application, namely a stack impedance spectrometer for each individual cell. 1 ref., 3 figs.

  2. Methodology for dynamic biaxial tension testing of pregnant uterine tissue.

    Science.gov (United States)

    Manoogian, Sarah; Mcnally, Craig; Calloway, Britt; Duma, Stefan

    2007-01-01

    Placental abruption accounts for 50% to 70% of fetal losses in motor vehicle crashes. Since automobile crashes are the leading cause of traumatic fetal injury mortality in the United States, research of this injury mechanism is important. Before research can adequately evaluate current and future restraint designs, a detailed model of the pregnant uterine tissues is necessary. The purpose of this study is to develop a methodology for testing the pregnant uterus in biaxial tension at a rate normally seen in a motor vehicle crash. Since the majority of previous biaxial work has established methods for quasi-static testing, this paper combines previous research and new methods to develop a custom designed system to strain the tissue at a dynamic rate. Load cells and optical markers are used for calculating stress strain curves of the perpendicular loading axes. Results for this methodology show images of a tissue specimen loaded and a finite verification of the optical strain measurement. The biaxial test system dynamically pulls the tissue to failure with synchronous motion of four tissue grips that are rigidly coupled to the tissue specimen. The test device models in situ loading conditions of the pregnant uterus and overcomes previous limitations of biaxial testing. A non-contact method of measuring strains combined with data reduction to resolve the stresses in two directions provides the information necessary to develop a three dimensional constitutive model of the material. Moreover, future research can apply this method to other soft tissues with similar in situ loading conditions.

  3. Dynamical habitability of planetary systems.

    Science.gov (United States)

    Dvorak, Rudolf; Pilat-Lohinger, Elke; Bois, Eric; Schwarz, Richard; Funk, Barbara; Beichman, Charles; Danchi, William; Eiroa, Carlos; Fridlund, Malcolm; Henning, Thomas; Herbst, Tom; Kaltenegger, Lisa; Lammer, Helmut; Léger, Alain; Liseau, René; Lunine, Jonathan; Paresce, Francesco; Penny, Alan; Quirrenbach, Andreas; Röttgering, Huub; Selsis, Frank; Schneider, Jean; Stam, Daphne; Tinetti, Giovanna; White, Glenn J

    2010-01-01

    The problem of the stability of planetary systems, a question that concerns only multiplanetary systems that host at least two planets, is discussed. The problem of mean motion resonances is addressed prior to discussion of the dynamical structure of the more than 350 known planets. The difference with regard to our own Solar System with eight planets on low eccentricity is evident in that 60% of the known extrasolar planets have orbits with eccentricity e > 0.2. We theoretically highlight the studies concerning possible terrestrial planets in systems with a Jupiter-like planet. We emphasize that an orbit of a particular nature only will keep a planet within the habitable zone around a host star with respect to the semimajor axis and its eccentricity. In addition, some results are given for individual systems (e.g., Gl777A) with regard to the stability of orbits within habitable zones. We also review what is known about the orbits of planets in double-star systems around only one component (e.g., gamma Cephei) and around both stars (e.g., eclipsing binaries).

  4. Asphalt mix characterization using dynamic modulus and APA testing.

    Science.gov (United States)

    2005-11-01

    final report summarizes two research efforts related to asphalt mix characterization: dynamic modulus and Asphalt Pavement Analyzer testing. One phase of the research consisted of a laboratory-based evaluation of dynamic modulus of Oregon dense-grade...

  5. Test System Impact on System Availability

    DEFF Research Database (Denmark)

    Pau, L. F.

    1987-01-01

    The specifications are presented for an imperfect automatic test system (ATS) (test frequency distribution, reliability, false alarm rate, nondetection rate) in order to account for the availability, readiness, mean time between unscheduled repairs (MTBUR), reliability, and maintenance of the sys......The specifications are presented for an imperfect automatic test system (ATS) (test frequency distribution, reliability, false alarm rate, nondetection rate) in order to account for the availability, readiness, mean time between unscheduled repairs (MTBUR), reliability, and maintenance...... of the system subject to monitoring and test. A time-dependent Markov model is presented, and applied in three cases, with examples of numerical results provided for preventive maintenance decisions, design of an automatic test system, buffer testing in computers, and data communications....

  6. Testing substellar models with dynamical mass measurements

    Directory of Open Access Journals (Sweden)

    Liu M.C.

    2011-07-01

    Full Text Available We have been using Keck laser guide star adaptive optics to monitor the orbits of ultracool binaries, providing dynamical masses at lower luminosities and temperatures than previously available and enabling strong tests of theoretical models. We have identified three specific problems with theory: (1 We find that model color–magnitude diagrams cannot be reliably used to infer masses as they do not accurately reproduce the colors of ultracool dwarfs of known mass. (2 Effective temperatures inferred from evolutionary model radii are typically inconsistent with temperatures derived from fitting atmospheric models to observed spectra by 100–300 K. (3 For the only known pair of field brown dwarfs with a precise mass (3% and age determination (≈25%, the measured luminosities are ~2–3× higher than predicted by model cooling rates (i.e., masses inferred from Lbol and age are 20–30% larger than measured. To make progress in understanding the observed discrepancies, more mass measurements spanning a wide range of luminosity, temperature, and age are needed, along with more accurate age determinations (e.g., via asteroseismology for primary stars with brown dwarf binary companions. Also, resolved optical and infrared spectroscopy are needed to measure lithium depletion and to characterize the atmospheres of binary components in order to better assess model deficiencies.

  7. Dynamic Investigation Test-rig on hAptics (DITA)

    International Nuclear Information System (INIS)

    Cannella, F; Olivieri, E; Caldwell, D G; Scalise, L; Memeo, M

    2013-01-01

    Research on tactile sensitivity has been conducted since the last century and many devices have been proposed to study in detail this sense through experimental tests. The sense of touch is essential in every-day life of human beings, but it can also play a fundamental role for the assessment of some neurological disabilities and pathologies. In fact, the level of tactile perception can provide information on the health state of the nervous system. In this paper, authors propose the design and development of a novel test apparatus, named DITA (Dynamic Investigation Test-rig on hAptics), aiming to provide the measurement of the tactile sensitivity trough the determination of the Just Noticeable Difference (JND) curve of a subject. The paper reports the solution adopted for the system design and the results obtained on the set of experiments carried out on volunteers

  8. Topological dimension and dynamical systems

    CERN Document Server

    Coornaert, Michel

    2015-01-01

    Translated from the popular French edition, the goal of the book is to provide a self-contained introduction to mean topological dimension, an invariant of dynamical systems introduced in 1999 by Misha Gromov. The book examines how this invariant was successfully used by Elon Lindenstrauss and Benjamin Weiss to answer a long-standing open question about embeddings of minimal dynamical systems into shifts. A large number of revisions and additions have been made to the original text. Chapter 5 contains an entirely new section devoted to the Sorgenfrey line. Two chapters have also been added: Chapter 9 on amenable groups and Chapter 10 on mean topological dimension for continuous actions of countable amenable groups. These new chapters contain material that have never before appeared in textbook form. The chapter on amenable groups is based on Følner’s characterization of amenability and may be read independently from the rest of the book. Although the contents of this book lead directly to several active ar...

  9. System dynamics for mechanical engineers

    CERN Document Server

    Davies, Matthew

    2015-01-01

    This textbook is ideal for mechanical engineering students preparing to enter the workforce during a time of rapidly accelerating technology, where they will be challenged to join interdisciplinary teams. It explains system dynamics using analogies familiar to the mechanical engineer while introducing new content in an intuitive fashion. The fundamentals provided in this book prepare the mechanical engineer to adapt to continuous technological advances with topics outside traditional mechanical engineering curricula by preparing them to apply basic principles and established approaches to new problems. This book also: ·         Reinforces the connection between the subject matter and engineering reality ·         Includes an instructor pack with the online publication that describes in-class experiments with minimal preparation requirements ·         Provides content dedicated to the modeling of modern interdisciplinary technological subjects, including opto-mechanical systems, high...

  10. Dynamics of complex quantum systems

    CERN Document Server

    Akulin, Vladimir M

    2014-01-01

    This book gathers together a range of similar problems that can be encountered in different fields of modern quantum physics and that have common features with regard to multilevel quantum systems. The main motivation was to examine from a uniform standpoint various models and approaches that have been developed in atomic, molecular, condensed matter, chemical, laser and nuclear physics in various contexts. The book should help senior-level undergraduate, graduate students and researchers putting particular problems in these fields into a broader scientific context and thereby taking advantage of well-established techniques used in adjacent fields. This second edition has been expanded to include substantial new material (e.g. new sections on Dynamic Localization and on Euclidean Random Matrices and new chapters on Entanglement, Open Quantum Systems, and Coherence Protection). It is based on the author’s lectures at the Moscow Institute of Physics and Technology, at the CNRS Aimé Cotton Laboratory, and on ...

  11. Nonlinear dynamics non-integrable systems and chaotic dynamics

    CERN Document Server

    Borisov, Alexander

    2017-01-01

    This monograph reviews advanced topics in the area of nonlinear dynamics. Starting with theory of integrable systems – including methods to find and verify integrability – the remainder of the book is devoted to non-integrable systems with an emphasis on dynamical chaos. Topics include structural stability, mechanisms of emergence of irreversible behaviour in deterministic systems as well as chaotisation occurring in dissipative systems.

  12. Stability in dynamical systems I

    International Nuclear Information System (INIS)

    Courant, E.D.; Ruth, R.D.; Weng, W.T.

    1984-08-01

    We have reviewed some of the basic techniques which can be used to analyze stability in nonlinear dynamical systems, particularly in circular particle accelerators. We have concentrated on one-dimensional systems in the examples in order to simply illustrate the general techniques. We began with a review of Hamiltonian dynamics and canonical transformations. We then reviewed linear equations with periodic coefficients using the basic techniques from accelerator theory. To handle nonlinear terms we developed a canonical perturbation theory. From this we calculated invariants and the amplitude dependence of the frequency. This led us to resonances. We studied the cubic resonance in detail by using a rotating coordinate system in phase space. We then considered a general isolated nonlinear resonance. In this case we calculated the width of the resonance and estimated the spacing of resonances in order to use the Chirikov criterion to restrict the validity of the analysis. Finally the resonance equation was reduced to the pendulum equation, and we examined the motion on a separatrix. This brought us to the beginnings of stochastic behavior in the neighborhood of the separatrix. It is this complex behavior in the neighborhood of the separatrix which causes the perturbation theory used here to diverge in many cases. In spite of this the methods developed here have been and are used quite successfully to study nonlinear effects in nearly integrable systems. When used with caution and in conjunction with numerical work they give tremendous insight into the nature of the phase space structure and the stability of nonlinear differential equations. 14 references

  13. Thermospheric dynamics - A system theory approach

    Science.gov (United States)

    Codrescu, M.; Forbes, J. M.; Roble, R. G.

    1990-01-01

    A system theory approach to thermospheric modeling is developed, based upon a linearization method which is capable of preserving nonlinear features of a dynamical system. The method is tested using a large, nonlinear, time-varying system, namely the thermospheric general circulation model (TGCM) of the National Center for Atmospheric Research. In the linearized version an equivalent system, defined for one of the desired TGCM output variables, is characterized by a set of response functions that is constructed from corresponding quasi-steady state and unit sample response functions. The linearized version of the system runs on a personal computer and produces an approximation of the desired TGCM output field height profile at a given geographic location.

  14. Model tests on dynamic performance of RC shear walls

    International Nuclear Information System (INIS)

    Nagashima, Toshio; Shibata, Akenori; Inoue, Norio; Muroi, Kazuo.

    1991-01-01

    For the inelastic dynamic response analysis of a reactor building subjected to earthquakes, it is essentially important to properly evaluate its restoring force characteristics under dynamic loading condition and its damping performance. Reinforced concrete shear walls are the main structural members of a reactor building, and dominate its seismic behavior. In order to obtain the basic information on the dynamic restoring force characteristics and damping performance of shear walls, the dynamic test using a large shaking table, static displacement control test and the pseudo-dynamic test on the models of a shear wall were conducted. In the dynamic test, four specimens were tested on a large shaking table. In the static test, four specimens were tested, and in the pseudo-dynamic test, three specimens were tested. These tests are outlined. The results of these tests were compared, placing emphasis on the restoring force characteristics and damping performance of the RC wall models. The strength was higher in the dynamic test models than in the static test models mainly due to the effect of loading rate. (K.I.)

  15. The improvement of dynamic universal testing machine for hot cell usages

    International Nuclear Information System (INIS)

    Ahn, Sang Bok; Lee, Key Soon; Park, Dae Kyu; Hong, Kwon Pyo; Choo, Yong Sun

    1998-01-01

    Dynamic universal testing machine(UTM) were developed for hot cell usages, which can perform tensile, compression, bending, fracture toughness and fatigue crack growth tests. In this report, technical reviews in the course of developing machine were described. Detailed subjects are as follows; 1. Outline of testing method using dynamic UTM 2. Detailed testing system organizations 3. Technical specification to develop machine 4. Setting up load string 5. Inspection and pre-commissioning tests on machine. (author). 14 figs

  16. Emulation tool of dynamic systems via internet

    Directory of Open Access Journals (Sweden)

    Daniel Ruiz Olaya

    2015-11-01

    Full Text Available The experimentation laboratories for the studies of control system courses can become expensive, either in its acquisition, operation or maintenance. An alternative resource have been the remote laboratories. However, not always is possible to get complex systems. A solution to this matter are the remote emulation laboratories. In this paper describes the development of a Web application for the emulation of dynamic systems using a free-distribution software tool of rapid control prototyping based on Linux/RTAI. This application is focused especially for the experimentation with dynamic systems that are not available easily in a laboratory where the model have been configured by the user. The design of the front-end and the back-end are presented. The latency times of the real-time operating system and the ability of the system to reproduce similar signals to a real system from an emulated model were verified. An example, to test the functionality of the application the model of an evaporator was used. One of the advantages of the application is the work methodology which is based on the development of blocks in Scicos. This allows the user to reuse those parameters and the code that was implemented to build a block on the Scicos toolbox with the Linux/RTAI/ScicosLab environment. Moreover, only a web-browser and the Java Virtual Machine are required.

  17. Development of DCC software dynamic test facility: past and future

    International Nuclear Information System (INIS)

    McDonald, A.M.; Thai, N.D.; Buijs, W.J.

    1996-01-01

    This paper describes a test facility for future dynamic testing of DCC software used in the control computers of CANDU nuclear power stations. It is a network of three computers: the DCC emulator, the dynamic CANDU plant simulator and the testing computer. Shared network files are used for input/output data exchange between computers. The DCC emulator runs directly on the binary image of the DCC software. The dynamic CANDU plant simulator accepts control signals from the DCC emulator and returns realistic plant behaviour. The testing computer accepts test scripts written in AECL Test Language. Both dynamic test and static tests may be performed on the DCC software to verify control program outputs and dynamic responses. (author)

  18. Analysis of Dynamic Stiffness of Bridge Cap-Pile System

    Directory of Open Access Journals (Sweden)

    Jinhui Chu

    2018-01-01

    Full Text Available In order to investigate the applicability of dynamic stiffness for bridge cap-pile system, a laboratory test was performed. A numerical model was also built for this type of system. The impact load was applied on the cap top and the dynamic stiffness was analysed. Then, the effect of the effective friction area between pile and soil was also considered. Finally, the dynamic stiffness relationship between the single pile and the cap-pile system was also compared. The results show that the dynamic stiffness is a sensitive index and can well reflect the static characteristics of the pile at the elastic stage. There is a significant positive correlation between the vertical dynamic stiffness index and bearing capacity of the cap-pile system in the similar formation environment. For the cap-pile system with four piles, the dynamic stiffness is about four times as large as the single pile between 10 and 20 Hz.

  19. Puzzling with potential: dynamic testing of analogical reasoning in children

    OpenAIRE

    Stevenson, Claire Elisabeth

    2012-01-01

    Assessment procedures are frequent in children's school careers; however, measuring potential for learning has remained a puzzle. Dynamic testing is a method to assess cognitive potential that includes training in the assessment process. The goal of this thesis project was to develop a new dynamic test of analogical reasoning for school children. The main aims were to (1) investigate factors that influence children’s differences in performance and change during dynamic testing and (2) examine...

  20. Effect of noise on the bifurcation behavior of nonlinear dynamical systems

    Energy Technology Data Exchange (ETDEWEB)

    Serletis, Apostolos [Department of Economics, University of Calgary, Calgary, Alta., T2N 1N4 (Canada)]. E-mail: Serletis@ucalgary.ca; Shahmoradi, Asghar [Faculty of Economics, University of Tehran, Tehran (Iran, Islamic Republic of); Serletis, Demitre [Division of Neurosurgery, University of Toronto, Toronto, Ont., M5G 1L5 (Canada)

    2007-08-15

    We argue that dynamical noise can dramatically change the dynamics of low dimensional chaotic systems. Moreover, we show that chaos tests are highly sensitive to dynamical noise and this becomes worse when the intensity of the noise increases.

  1. Using Spare Logic Resources To Create Dynamic Test Points

    Science.gov (United States)

    Katz, Richard; Kleyner, Igor

    2011-01-01

    A technique has been devised to enable creation of a dynamic set of test points in an embedded digital electronic system. As a result, electronics contained in an application specific circuit [e.g., gate array, field programmable gate array (FPGA)] can be internally probed, even when contained in a closed housing during all phases of test. In the present technique, the test points are not fixed and limited to a small number; the number of test points can vastly exceed the number of buffers or pins, resulting in a compact footprint. Test points are selected by means of spare logic resources within the ASIC(s) and/or FPGA(s). A register is programmed with a command, which is used to select the signals that are sent off-chip and out of the housing for monitoring by test engineers and external test equipment. The register can be commanded by any suitable means: for example, it could be commanded through a command port that would normally be used in the operation of the system. In the original application of the technique, commanding of the register is performed via a MIL-STD-1553B communication subsystem.

  2. Dynamical systems of algebraic origin

    CERN Document Server

    Schmidt, Klaus

    1995-01-01

    Although much of classical ergodic theory is concerned with single transformations and one-parameter flows, the subject inherits from statistical mechanics not only its name, but also an obligation to analyze spatially extended systems with multidimensional symmetry groups. However, the wealth of concrete and natural examples which has contributed so much to the appeal and development of classical dynamics, is noticeably absent in this more general theory. The purpose of this book is to help remedy this scarcity of explicit examples by introducing a class of continuous Zd-actions diverse enough to exhibit many of the new phenomena encountered in the transition from Z to Zd, but which nevertheless lends itself to systematic study: the Zd-actions by automorphisms of compact, abelian groups. One aspect of these actions, not surprising in itself but quite striking in its extent and depth nonetheless, is the connection with commutative algebra and arithmetical algebraic geometry. The algebraic framework resulting...

  3. Dynamic mode decomposition for compressive system identification

    Science.gov (United States)

    Bai, Zhe; Kaiser, Eurika; Proctor, Joshua L.; Kutz, J. Nathan; Brunton, Steven L.

    2017-11-01

    Dynamic mode decomposition has emerged as a leading technique to identify spatiotemporal coherent structures from high-dimensional data. In this work, we integrate and unify two recent innovations that extend DMD to systems with actuation and systems with heavily subsampled measurements. When combined, these methods yield a novel framework for compressive system identification, where it is possible to identify a low-order model from limited input-output data and reconstruct the associated full-state dynamic modes with compressed sensing, providing interpretability of the state of the reduced-order model. When full-state data is available, it is possible to dramatically accelerate downstream computations by first compressing the data. We demonstrate this unified framework on simulated data of fluid flow past a pitching airfoil, investigating the effects of sensor noise, different types of measurements (e.g., point sensors, Gaussian random projections, etc.), compression ratios, and different choices of actuation (e.g., localized, broadband, etc.). This example provides a challenging and realistic test-case for the proposed method, and results indicate that the dominant coherent structures and dynamics are well characterized even with heavily subsampled data.

  4. CMIF ECLS system test findings

    Science.gov (United States)

    Schunk, Richard G.; Carrasquillo, Robyn L.; Ogle, Kathyrn Y.; Wieland, Paul O.; Bagdigian, Robert M.

    1989-01-01

    During 1987 three Space Station integrated Environmental Control and Life Support System (ECLSS) tests were conducted at the Marshall Space Flight Center (MSFC) Core Module Integration Facility (CMIF) as part of the MSFC ECLSS Phase II test program. The three tests ranged in duration from 50 to 150 hours and were conducted inside of the CMIF module simulator. The Phase II partial integrated system test configuration consisted of four regenerative air revitalization subsystems and one regenerative water reclamation subsystem. This paper contains a discussion of results and lessons learned from the Phase II test program. The design of the Phase II test configuration and improvements made throughout the program are detailed. Future plans for the MSFC CMIF test program are provided, including an overview of planned improvements for the Phase III program.

  5. Optimal design and dynamic impact tests of removable bollards

    Science.gov (United States)

    Chen, Suwen; Liu, Tianyi; Li, Guoqiang; Liu, Qing; Sun, Jianyun

    2017-10-01

    Anti-ram bollard systems, which are installed around buildings and infrastructure, can prevent unauthorized vehicles from entering, maintain distance from vehicle-borne improvised explosive devices (VBIED) and reduce the corresponding damage. Compared with a fixed bollard system, a removable bollard system provides more flexibility as it can be removed when needed. This paper first proposes a new type of K4-rated removable anti-ram bollard system. To simulate the collision of a vehicle hitting the bollard system, a finite element model was then built and verified through comparison of numerical simulation results and existing experimental results. Based on the orthogonal design method, the factors influencing the safety and economy of this proposed system were examined and sorted according to their importance. An optimal design scheme was then produced. Finally, to validate the effectiveness of the proposed design scheme, four dynamic impact tests, including two front impact tests and two side impact tests, have been conducted according to BSI Specifications. The residual rotation angles of the specimen are smaller than 30º and satisfy the requirements of the BSI Specification.

  6. Dynamical Signatures of Living Systems

    Science.gov (United States)

    Zak, M.

    1999-01-01

    One of the main challenges in modeling living systems is to distinguish a random walk of physical origin (for instance, Brownian motions) from those of biological origin and that will constitute the starting point of the proposed approach. As conjectured, the biological random walk must be nonlinear. Indeed, any stochastic Markov process can be described by linear Fokker-Planck equation (or its discretized version), only that type of process has been observed in the inanimate world. However, all such processes always converge to a stable (ergodic or periodic) state, i.e., to the states of a lower complexity and high entropy. At the same time, the evolution of living systems directed toward a higher level of complexity if complexity is associated with a number of structural variations. The simplest way to mimic such a tendency is to incorporate a nonlinearity into the random walk; then the probability evolution will attain the features of diffusion equation: the formation and dissipation of shock waves initiated by small shallow wave disturbances. As a result, the evolution never "dies:" it produces new different configurations which are accompanied by an increase or decrease of entropy (the decrease takes place during formation of shock waves, the increase-during their dissipation). In other words, the evolution can be directed "against the second law of thermodynamics" by forming patterns outside of equilibrium in the probability space. Due to that, a specie is not locked up in a certain pattern of behavior: it still can perform a variety of motions, and only the statistics of these motions is constrained by this pattern. It should be emphasized that such a "twist" is based upon the concept of reflection, i.e., the existence of the self-image (adopted from psychology). The model consists of a generator of stochastic processes which represents the motor dynamics in the form of nonlinear random walks, and a simulator of the nonlinear version of the diffusion

  7. Dynamic Performance Characteristic Tests of Real Scale Lead Rubber Bearing for the Evaluation of Performance Criteria

    International Nuclear Information System (INIS)

    Kim, Min Kyu; Kim, Jung-Han; Choi, In-Kil

    2014-01-01

    Dynamic characteristic tests of full scale lead rubber bearing were performed for the evaluation of performance criteria of isolation system for nuclear power plants. For the dynamic test for a full scale rubber bearing, two 1500mm diameter lead rubber bearings were manufactured. The viewpoints of this dynamic test are determination of an ultimate shear strain level of lead rubber bearing, behavior of rubber bearing according to static and dynamic input motion, sinusoidal and random (earthquake) motion, and 1-dimentional and 2-dimensional input motion. In this study, seismic isolation device tests were performed for the evaluation of performance criteria of isolation system. Through this test, it can be recognized that in the case of considering a mechanical property test, dynamic and multi degree of loading conditions should be determined. But these differences should be examined how much affect to the global structural behavior

  8. Atlantic Test Range. Dynamic RCS Measurement Capability

    National Research Council Canada - National Science Library

    2000-01-01

    .... These systems include radars (fighter/attack, sea surveillance, and AEW), Navigation (IFF, GPS, and INS), communications (voice and data link), reconnaissance systems, antenna systems, forward looking infrared systems and ASW systems...

  9. Feasibility Study of a Magnetic Suspension System for Testing the Dynamic Stability of Blunt Bodies in NASA GRC’s 225 square centimeter Supersonic Wind Tunnel

    Data.gov (United States)

    National Aeronautics and Space Administration — The dynamic stability of blunt bodies during planetary entry is difficult to quantify as computational methods have yet to demonstrate accurate predictive...

  10. Resetting dynamic behaviour of pipework systems

    International Nuclear Information System (INIS)

    Gaudin, M.

    1997-01-01

    Resetting models is applied to electricity generating plant pipework systems. A frequency approach to the problem is made in an original way thanks to the use of precise dynamic rigidity matrices. The method assumes two kinds of unknown: the usually processed mechanical characteristics (Young's Modulus, density etc.) and new resetting parameters acting on the dynamic behaviour of unknown connections. As the latter have a very wide range of possible variation, they benefit from a change of variable which allows the assumptions formulated to be complied with. The minimized cost function is based on a error in load. The frequencies required for building it are automatically selected thanks to different tests on measurements. Minimization uses a sensitivity technique linked with a method of least standard squares. The method has been programmed in Fortran 90 within the CIRCUS code and tried out on various examples which were simulated and sound effects cases as well as an actual case. (author)

  11. Architectural Analysis of Dynamically Reconfigurable Systems

    Science.gov (United States)

    Lindvall, Mikael; Godfrey, Sally; Ackermann, Chris; Ray, Arnab; Yonkwa, Lyly

    2010-01-01

    oTpics include: the problem (increased flexibility of architectural styles decrease analyzability, behavior emerges and varies depending on the configuration, does the resulting system run according to the intended design, and architectural decisions can impede or facilitate testing); top down approach to architecture analysis, detection of defects and deviations, and architecture and its testability; currently targeted projects GMSEC and CFS; analyzing software architectures; analyzing runtime events; actual architecture recognition; GMPUB in Dynamic SAVE; sample output from new approach; taking message timing delays into account; CFS examples of architecture and testability; some recommendations for improved testablity; and CFS examples of abstract interfaces and testability; CFS example of opening some internal details.

  12. Dynamic testing of nuclear power plant structures: an evaluation

    International Nuclear Information System (INIS)

    Weaver, H.J.

    1980-02-01

    Lawrence Livermore Laboratory (LLL) evaluated the applications of system identification techniques to the dynamic testing of nuclear power plant structures and subsystems. These experimental techniques involve exciting a structure and measuring, digitizing, and processing the time-history motions that result. The data can be compared to parameters calculated using finite element or other models of the test systems to validate the model and to verify the seismic analysis. This report summarizes work in three main areas: (1) analytical qualification of a set of computer programs developed at LLL to extract model parameters from the time histories; (2) examination of the feasibility of safely exciting nuclear power plant structures and accurately recording the resulting time-history motions; (3) study of how the model parameters that are extracted from the data be used best to evaluate structural integrity and analyze nuclear power plants

  13. Dynamical System Approaches to Combinatorial Optimization

    DEFF Research Database (Denmark)

    Starke, Jens

    2013-01-01

    of large times as an asymptotically stable point of the dynamics. The obtained solutions are often not globally optimal but good approximations of it. Dynamical system and neural network approaches are appropriate methods for distributed and parallel processing. Because of the parallelization......Several dynamical system approaches to combinatorial optimization problems are described and compared. These include dynamical systems derived from penalty methods; the approach of Hopfield and Tank; self-organizing maps, that is, Kohonen networks; coupled selection equations; and hybrid methods...... thereof can be used as models for many industrial problems like manufacturing planning and optimization of flexible manufacturing systems. This is illustrated for an example in distributed robotic systems....

  14. Urban eco-efficiency and system dynamics modelling

    Energy Technology Data Exchange (ETDEWEB)

    Hradil, P., Email: petr.hradil@vtt.fi

    2012-06-15

    Assessment of urban development is generally based on static models of economic, social or environmental impacts. More advanced dynamic models have been used mostly for prediction of population and employment changes as well as for other macro-economic issues. This feasibility study was arranged to test the potential of system dynamic modelling in assessing eco-efficiency changes during urban development. (orig.)

  15. Space Fission System Test Effectiveness

    International Nuclear Information System (INIS)

    Houts, Mike; Schmidt, Glen L.; Van Dyke, Melissa; Godfroy, Tom; Martin, James; Bragg-Sitton, Shannon; Dickens, Ricky; Salvail, Pat; Harper, Roger

    2004-01-01

    Space fission technology has the potential to enable rapid access to any point in the solar system. If fission propulsion systems are to be developed to their full potential, however, near-term customers need to be identified and initial fission systems successfully developed, launched, and utilized. One key to successful utilization is to develop reactor designs that are highly testable. Testable reactor designs have a much higher probability of being successfully converted from paper concepts to working space hardware than do designs which are difficult or impossible to realistically test. ''Test Effectiveness'' is one measure of the ability to realistically test a space reactor system. The objective of this paper is to discuss test effectiveness as applied to the design, development, flight qualification, and acceptance testing of space fission systems. The ability to perform highly effective testing would be particularly important to the success of any near-term mission, such as NASA's Jupiter Icy Moons Orbiter, the first mission under study within NASA's Project Prometheus, the Nuclear Systems Program

  16. Structural system identification: Structural dynamics model validation

    Energy Technology Data Exchange (ETDEWEB)

    Red-Horse, J.R.

    1997-04-01

    Structural system identification is concerned with the development of systematic procedures and tools for developing predictive analytical models based on a physical structure`s dynamic response characteristics. It is a multidisciplinary process that involves the ability (1) to define high fidelity physics-based analysis models, (2) to acquire accurate test-derived information for physical specimens using diagnostic experiments, (3) to validate the numerical simulation model by reconciling differences that inevitably exist between the analysis model and the experimental data, and (4) to quantify uncertainties in the final system models and subsequent numerical simulations. The goal of this project was to develop structural system identification techniques and software suitable for both research and production applications in code and model validation.

  17. Routine testing on protective and safety systems and components

    International Nuclear Information System (INIS)

    Rysy, W.

    1977-01-01

    1) In-process inspection, tests during commissioning. 2) Tests during reactor operation. 2.1) Reactor protection system, for example: continuous auto-testing by a dynamic system, check of the output signals; 2.2) safety features: selected examples: functional tests on the ECCS, trial operation of the emergency diesels. 3) Tests during refuelling phase. 3.1) Containment: Leakage rate tests, leak testing; 3.2) coolant system: selected examples: inservice inspections of the pressure vessel, eddy current testing of the steam generator, functional tests of safety valves. (orig./HP) [de

  18. Dynamic Stability Experiment of Maglev Systems,

    Science.gov (United States)

    1995-04-01

    This report summarizes the research performed on maglev vehicle dynamic stability at Argonne National Laboratory during the past few years. It also... maglev system, it is important to consider this phenomenon in the development of all maglev systems. This report presents dynamic stability experiments...on maglev systems and compares their numerical simulation with predictions calculated by a nonlinear dynamic computer code. Instabilities of an

  19. Biomechanical assessment of dynamic balance: Specificity of different balance tests.

    Science.gov (United States)

    Ringhof, Steffen; Stein, Thorsten

    2018-04-01

    Dynamic balance is vitally important for most sports and activities of daily living, so the assessment of dynamic stability has become an important issue. In consequence, a large number of balance tests have been developed. However, it is not yet known whether these tests (i) measure the same construct and (ii) can differentiate between athletes with different balance expertise. We therefore studied three common dynamic balance tests: one-leg jump landings, Posturomed perturbations and simulated forward falls. Participants were 24 healthy young females in regular training in either gymnastics (n = 12) or swimming (n = 12). In each of the tests, the participants were instructed to recover balance as quickly as possible. Dynamic stability was computed by time to stabilization and margin of stability, deduced from force plates and motion capture respectively. Pearson's correlations between the dynamic balance tests found no significant associations between the respective dynamic stability measures. Furthermore, independent t-tests indicated that only jump landings could properly distinguish between both groups of athletes. In essence, the different dynamic balance tests applied did not measure the same construct but rather task-specific skills, each of which depends on multifactorial internal and external constraints. Our study therefore contradicts the traditional view of considering balance as a general ability, and reinforces that dynamic balance measures are not interchangeable. This highlights the importance of selecting appropriate balance tests. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. Plan for dynamic testing of NFS tank and vault

    International Nuclear Information System (INIS)

    1977-12-01

    (Nuclear Fuel Services) dynamic testing methodologies are described including the determination of resonant frequencies, mode shapes and the associated structural damping. The application of dynamic testing to the determination of the eigenparameters of the neutralized waste tanks 8D-2 and 8D-1 investigated and recommendations made

  1. Attractors for discrete periodic dynamical systems

    Science.gov (United States)

    John E. Franke; James F. Selgrade

    2003-01-01

    A mathematical framework is introduced to study attractors of discrete, nonautonomous dynamical systems which depend periodically on time. A structure theorem for such attractors is established which says that the attractor of a time-periodic dynamical system is the unin of attractors of appropriate autonomous maps. If the nonautonomous system is a perturbation of an...

  2. An Axiomatic Representation of System Dynamics

    CERN Document Server

    Baianu, I

    2004-01-01

    An axiomatic representation of system dynamics is introduced in terms of categories, functors, organismal supercategories, limits and colimits of diagrams. Specific examples are considered in Complex Systems Biology, such as ribosome biogenesis and Hormonal Control in human subjects. "Fuzzy" Relational Structures are also proposed for flexible representations of biological system dynamics and organization.

  3. Controlling chaos in discontinuous dynamical systems

    International Nuclear Information System (INIS)

    Danca, Marius-F.

    2004-01-01

    In this paper we consider the possibility to implement the technique of changes in the system variables to control the chaos introduced by Gueemez and Matias for continuous dynamical systems to a class of discontinuous dynamical systems. The approach is realized via differential inclusions following the Filippov theory. Three practical examples are considered

  4. Dynamism in Electronic Performance Support Systems.

    Science.gov (United States)

    Laffey, James

    1995-01-01

    Describes a model for dynamic electronic performance support systems based on NNAble, a system developed by the training group at Apple Computer. Principles for designing dynamic performance support are discussed, including a systems approach, performer-centered design, awareness of situated cognition, organizational memory, and technology use.…

  5. Availability of periodically tested systems

    International Nuclear Information System (INIS)

    Signoret, J.P.

    1979-01-01

    There is at the present time a need in accurate models to asess the availability of periodically tested stand-by systems. This paper shows how to improve the well known 'saw-tooth curve' model in order to take into account various reliability parameters. A model is developed to assess the pointwise and the mean availabilities of periodically tested stand-by systems. Exact and approxination formulae are given. In addition, the model developed herein leads to optimize the test interval in order to minimize the mean unavailability. A safety diesel in a nuclear power plant is given as an example

  6. Reactor primary pumps dynamic balancing test

    International Nuclear Information System (INIS)

    Lu Qunxian

    2002-01-01

    Reactor primary Pump is the important equipment in the primary circuit, its working quality would directly influence the safety and operation of nuclear power plant. The author describes that the primary pump vibration status, vibration fault diagnosis and dynamic balancing process on site have been performed since commercial operation of DA YA BAY Nuclear Power plant

  7. 基于LabVIEW的现场动平衡测试系统的开发%Development of field dynamic balance testing system based on LabVIEW

    Institute of Scientific and Technical Information of China (English)

    粱召华; 李智

    2014-01-01

    In order to adapt to the needs of the rotor field dynamic balance and improve the testing accuracy,the field dy-namic balance testing system based on virtual instrument technology was developed,which uses correlation method to extract the amplitude and phase of the vibration signal accurately , and adopts single-side dynamic balance and double-side dynamic balance method based on influence coefficient method to do the dynamic balance experiment. Many rotor dynamic balance experi-ments on the multi-function rotor testing bench show that the unbalance vibration has been effectively suppressed and the vibra-tion amplitude has been reduced obviously after adding appropriate testing weight on the rotor. This has important significance for reducing machine noise and the bearing wear,and improving the performance and life of the machine. It is also helpful to im-prove the machine's work efficiency and to ensure the safety of machining operators.%为了适应转子现场动平衡的需要,提高测试精度,开发了基于虚拟仪器技术的现场动平衡测试系统,它利用相关法准确提取出振动信号的幅值和相位,采用基于影响系数法的单面动平衡和双面动平衡的方法进行动平衡实验。通过在多功能转子试验台上做了多次转子动平衡试验,实验结果表明:转子在加适当的试重后不平衡振动得到了有效的抑制,振动幅度明显减小。这对于减小机器噪声和轴承磨损,提高机器的性能和寿命有着重要意义,同时也有助于提高机器的工作效率和保障机械加工操作者的安全。

  8. Attachment is a dynamic system

    Directory of Open Access Journals (Sweden)

    Zlatka Cugmas

    2003-04-01

    Full Text Available On the basis of the study of recent scientific literature about the development of attachment, the author answers the following questions: which are the postulates the theory of attachment has about the stability of the patterns of attachment, which level of stability in the patterns of attachment from infancy to adulthood these studies illuminate and which factors significantly influence the (instability of the patterns of attachment in time. The theory of attachment assumes that normal circumstances elicit stability. Changes, however, can be the result of important events influencing the sensitivity of the object of attachment. Agreement has not yet been reached regarding the percentage of stability in the patterns of attachment. There is more agreement regarding attachment in adulthood than that in childhood. The results depend on the size and characteristics of the subjects of the research, the measuring instruments, type of data analysis etc. The author concludes that attachment is a dynamic system influenced by significant changes in life (the cognitive development of the child, external care, parents' divorce, different stressful situations. As the influence of stressful events on the individual person' s quality of attachment is examined, it is necessary to consider also his/her temperamental characteristics, role of other people in their lives, etc.

  9. Advisory expert system for test rig operator

    International Nuclear Information System (INIS)

    Zielczynski, P.

    1994-01-01

    The advisory expert system MAESTRO (Modular Advisory Expert System for Test Rig Operator) has been designed to guide the operator of large experimental installation during start-up, steady state and shut down. The installation is located in the research reactor MARIA in the Institute of Atomic Energy in Swierk, Poland. The system acquires and analyses on line signals from installation and performs two tasks in real time: leading the operator and monitoring of the installation (including signal validation). Systems tasks, architecture and knowledge representation concepts are described. The system is based on expert systems techniques what makes in phases of continuous change of process parameters and it has been achieved by special knowledge representation allowing its dynamical modification. (author). 147 refs, 42 figs, 5 tab

  10. Multibody system dynamics, robotics and control

    CERN Document Server

    Gerstmayr, Johannes

    2013-01-01

    The volume contains 19 contributions by international experts in the field of multibody system dynamics, robotics and control. The book aims to bridge the gap between the modeling of mechanical systems by means of multibody dynamics formulations and robotics. In the classical approach, a multibody dynamics model contains a very high level of detail, however, the application of such models to robotics or control is usually limited. The papers aim to connect the different scientific communities in multibody dynamics, robotics and control. Main topics are flexible multibody systems, humanoid robots, elastic robots, nonlinear control, optimal path planning, and identification.

  11. Reliability of dynamic systems under limited information.

    Energy Technology Data Exchange (ETDEWEB)

    Field, Richard V., Jr. (.,; .); Grigoriu, Mircea

    2006-09-01

    A method is developed for reliability analysis of dynamic systems under limited information. The available information includes one or more samples of the system output; any known information on features of the output can be used if available. The method is based on the theory of non-Gaussian translation processes and is shown to be particularly suitable for problems of practical interest. For illustration, we apply the proposed method to a series of simple example problems and compare with results given by traditional statistical estimators in order to establish the accuracy of the method. It is demonstrated that the method delivers accurate results for the case of linear and nonlinear dynamic systems, and can be applied to analyze experimental data and/or mathematical model outputs. Two complex applications of direct interest to Sandia are also considered. First, we apply the proposed method to assess design reliability of a MEMS inertial switch. Second, we consider re-entry body (RB) component vibration response during normal re-entry, where the objective is to estimate the time-dependent probability of component failure. This last application is directly relevant to re-entry random vibration analysis at Sandia, and may provide insights on test-based and/or model-based qualification of weapon components for random vibration environments.

  12. Development of dynamic Bayesian models for web application test management

    Science.gov (United States)

    Azarnova, T. V.; Polukhin, P. V.; Bondarenko, Yu V.; Kashirina, I. L.

    2018-03-01

    The mathematical apparatus of dynamic Bayesian networks is an effective and technically proven tool that can be used to model complex stochastic dynamic processes. According to the results of the research, mathematical models and methods of dynamic Bayesian networks provide a high coverage of stochastic tasks associated with error testing in multiuser software products operated in a dynamically changing environment. Formalized representation of the discrete test process as a dynamic Bayesian model allows us to organize the logical connection between individual test assets for multiple time slices. This approach gives an opportunity to present testing as a discrete process with set structural components responsible for the generation of test assets. Dynamic Bayesian network-based models allow us to combine in one management area individual units and testing components with different functionalities and a direct influence on each other in the process of comprehensive testing of various groups of computer bugs. The application of the proposed models provides an opportunity to use a consistent approach to formalize test principles and procedures, methods used to treat situational error signs, and methods used to produce analytical conclusions based on test results.

  13. Adaptive Integration of Nonsmooth Dynamical Systems

    Science.gov (United States)

    2017-10-11

    2017 W911NF-12-R-0012-03: Adaptive Integration of Nonsmooth Dynamical Systems The views, opinions and/or findings contained in this report are those of...Integration of Nonsmooth Dynamical Systems Report Term: 0-Other Email: drum@gwu.edu Distribution Statement: 1-Approved for public release; distribution is...classdrake_1_1systems_1_1_integrator_base.html ; 3) a solver for dynamical systems with arbitrary unilateral and bilateral constraints (the key component of the time stepping systems )- see

  14. Nonautonomous dynamical systems in the life sciences

    CERN Document Server

    Pötzsche, Christian

    2013-01-01

    Nonautonomous dynamics describes the qualitative behavior of evolutionary differential and difference equations, whose right-hand side is explicitly time dependent. Over recent years, the theory of such systems has developed into a highly active field related to, yet recognizably distinct from that of classical autonomous dynamical systems. This development was motivated by problems of applied mathematics, in particular in the life sciences where genuinely nonautonomous systems abound. The purpose of this monograph is to indicate through selected, representative examples how often nonautonomous systems occur in the life sciences and to outline the new concepts and tools from the theory of nonautonomous dynamical systems that are now available for their investigation.

  15. Logical entropy of quantum dynamical systems

    Directory of Open Access Journals (Sweden)

    Ebrahimzadeh Abolfazl

    2016-01-01

    Full Text Available This paper introduces the concepts of logical entropy and conditional logical entropy of hnite partitions on a quantum logic. Some of their ergodic properties are presented. Also logical entropy of a quantum dynamical system is dehned and ergodic properties of dynamical systems on a quantum logic are investigated. Finally, the version of Kolmogorov-Sinai theorem is proved.

  16. Incorporating Dynamical Systems into the Traditional Curriculum.

    Science.gov (United States)

    Natov, Jonathan

    2001-01-01

    Presents a brief overview of dynamical systems. Gives examples from dynamical systems and where they fit into the current curriculum. Points out that these examples are accessible to undergraduate freshmen and sophomore students, add continuity to the standard curriculum, and are worth including in classes. (MM)

  17. Reconceptualizing Learning as a Dynamical System.

    Science.gov (United States)

    Ennis, Catherine D.

    1992-01-01

    Dynamical systems theory can increase our understanding of the constantly evolving learning process. Current research using experimental and interpretive paradigms focuses on describing the attractors and constraints stabilizing the educational process. Dynamical systems theory focuses attention on critical junctures in the learning process as…

  18. Dynamics and control of hybrid mechanical systems

    NARCIS (Netherlands)

    Leonov, G.A.; Nijmeijer, H.; Pogromski, A.Y.; Fradkov, A.L.

    2010-01-01

    The papers in this edited volume aim to provide a better understanding of the dynamics and control of a large class of hybrid dynamical systems that are described by different models in different state space domains. They not only cover important aspects and tools for hybrid systems analysis and

  19. Dynamical entropy for infinite quantum systems

    International Nuclear Information System (INIS)

    Hudetz, T.

    1990-01-01

    We review the recent physical application of the so-called Connes-Narnhofer-Thirring entropy, which is the successful quantum mechanical generalization of the classical Kolmogorov-Sinai entropy and, by its very conception, is a dynamical entropy for infinite quantum systems. We thus comparingly review also the physical applications of the classical dynamical entropy for infinite classical systems. 41 refs. (Author)

  20. System dynamics modelling of situation awareness

    CSIR Research Space (South Africa)

    Oosthuizen, R

    2015-11-01

    Full Text Available . The feedback loops and delays in the Command and Control system also contribute to the complex dynamic behavior. This paper will build on existing situation awareness models to develop a System Dynamics model to support a qualitative investigation through...

  1. Systems-Dynamic Analysis for Neighborhood Study

    Science.gov (United States)

    Systems-dynamic analysis (or system dynamics (SD)) helps planners identify interrelated impacts of transportation and land-use policies on neighborhood-scale economic outcomes for households and businesses, among other applications. This form of analysis can show benefits and tr...

  2. Narcissistic group dynamics of multiparty systems

    NARCIS (Netherlands)

    Schruijer, S.G.L.

    2015-01-01

    Purpose – This paper aims to introduce and illustrate the notion of narcissistic group dynamics. It is claimed that narcissism does not simply reside within individuals but can be characteristic of groups and social systems. In this case, the focus is on narcissistic dynamics in multiparty systems.

  3. Bifurcation Control of Chaotic Dynamical Systems

    National Research Council Canada - National Science Library

    Wang, Hua O; Abed, Eyad H

    1992-01-01

    A nonlinear system which exhibits bifurcations, transient chaos, and fully developed chaos is considered, with the goal of illustrating the role of two ideas in the control of chaotic dynamical systems...

  4. Dynamic Causal Models and Autopoietic Systems

    Directory of Open Access Journals (Sweden)

    OLIVIER DAVID

    2007-01-01

    Full Text Available Dynamic Causal Modelling (DCM and the theory of autopoietic systems are two important conceptual frameworks. In this review, we suggest that they can be combined to answer important questions about self-organising systems like the brain. DCM has been developed recently by the neuroimaging community to explain, using biophysical models, the non-invasive brain imaging data are caused by neural processes. It allows one to ask mechanistic questions about the implementation of cerebral processes. In DCM the parameters of biophysical models are estimated from measured data and the evidence for each model is evaluated. This enables one to test different functional hypotheses (i.e., models for a given data set. Autopoiesis and related formal theories of biological systems as autonomous machines represent a body of concepts with many successful applications. However, autopoiesis has remained largely theoretical and has not penetrated the empiricism of cognitive neuroscience. In this review, we try to show the connections that exist between DCM and autopoiesis. In particular, we propose a simple modification to standard formulations of DCM that includes autonomous processes. The idea is to exploit the machinery of the system identification of DCMs in neuroimaging to test the face validity of the autopoietic theory applied to neural subsystems. We illustrate the theoretical concepts and their implications for interpreting electroencephalographic signals acquired during amygdala stimulation in an epileptic patient. The results suggest that DCM represents a relevant biophysical approach to brain functional organisation, with a potential that is yet to be fully evaluated

  5. Chaotic systems are dynamically random

    International Nuclear Information System (INIS)

    Svozil, K.

    1988-01-01

    The idea is put forward that the significant route to chaos is driven by recursive iterations of suitable evolution functions. The corresponding formal notion of randomness is not based on dynamic complexity rather than on static complexity. 24 refs. (Author)

  6. Dynamical systems on 2- and 3-manifolds

    CERN Document Server

    Grines, Viacheslav Z; Pochinka, Olga V

    2016-01-01

    This book provides an introduction to the topological classification of smooth structurally stable diffeomorphisms on closed orientable 2- and 3-manifolds.The topological classification is one of the main problems of the theory of dynamical systems and the results presented in this book are mostly for dynamical systems satisfying Smale's Axiom A. The main results on the topological classification of discrete dynamical systems are widely scattered among many papers and surveys. This book presents these results fluidly, systematically, and for the first time in one publication. Additionally, this book discusses the recent results on the topological classification of Axiom A diffeomorphisms focusing on the nontrivial effects of the dynamical systems on 2- and 3-manifolds. The classical methods and approaches which are considered to be promising for the further research are also discussed. < The reader needs to be familiar with the basic concepts of the qualitative theory of dynamical systems which are present...

  7. Partial dynamical systems, fell bundles and applications

    CERN Document Server

    Exel, Ruy

    2017-01-01

    Partial dynamical systems, originally developed as a tool to study algebras of operators in Hilbert spaces, has recently become an important branch of algebra. Its most powerful results allow for understanding structural properties of algebras, both in the purely algebraic and in the C*-contexts, in terms of the dynamical properties of certain systems which are often hiding behind algebraic structures. The first indication that the study of an algebra using partial dynamical systems may be helpful is the presence of a grading. While the usual theory of graded algebras often requires gradings to be saturated, the theory of partial dynamical systems is especially well suited to treat nonsaturated graded algebras which are in fact the source of the notion of "partiality". One of the main results of the book states that every graded algebra satisfying suitable conditions may be reconstructed from a partial dynamical system via a process called the partial crossed product. Running in parallel with partial dynamica...

  8. Stirling Engine Dynamic System Modeling

    Science.gov (United States)

    Nakis, Christopher G.

    2004-01-01

    The Thermo-Mechanical systems branch at the Glenn Research Center focuses a large amount time on Stirling engines. These engines will be used on missions where solar power is inefficient, especially in deep space. I work with Tim Regan and Ed Lewandowski who are currently developing and validating a mathematical model for the Stirling engines. This model incorporates all aspects of the system including, mechanical, electrical and thermodynamic components. Modeling is done through Simplorer, a program capable of running simulations of the model. Once created and then proven to be accurate, a model is used for developing new ideas for engine design. My largest specific project involves varying key parameters in the model and quantifying the results. This can all be done relatively trouble-free with the help of Simplorer. Once the model is complete, Simplorer will do all the necessary calculations. The more complicated part of this project is determining which parameters to vary. Finding key parameters depends on the potential for a value to be independently altered in the design. For example, a change in one dimension may lead to a proportional change to the rest of the model, and no real progress is made. Also, the ability for a changed value to have a substantial impact on the outputs of the system is important. Results will be condensed into graphs and tables with the purpose of better communication and understanding of the data. With the changing of these parameters, a more optimal design can be created without having to purchase or build any models. Also, hours and hours of results can be simulated in minutes. In the long run, using mathematical models can save time and money. Along with this project, I have many other smaller assignments throughout the summer. My main goal is to assist in the processes of model development, validation and testing.

  9. Nonlinear dynamics of fractional order Duffing system

    International Nuclear Information System (INIS)

    Li, Zengshan; Chen, Diyi; Zhu, Jianwei; Liu, Yongjian

    2015-01-01

    In this paper, we analyze the nonlinear dynamics of fractional order Duffing system. First, we present the fractional order Duffing system and the numerical algorithm. Second, nonlinear dynamic behaviors of Duffing system with a fixed fractional order is studied by using bifurcation diagrams, phase portraits, Poincare maps and time domain waveforms. The fractional order Duffing system shows some interesting dynamical behaviors. Third, a series of Duffing systems with different fractional orders are analyzed by using bifurcation diagrams. The impacts of fractional orders on the tendency of dynamical motion, the periodic windows in chaos, the bifurcation points and the distance between the first and the last bifurcation points are respectively studied, in which some basic laws are discovered and summarized. This paper reflects that the integer order system and the fractional order one have close relationship and an integer order system is a special case of fractional order ones.

  10. Dynamics of Open Systems with Affine Maps

    International Nuclear Information System (INIS)

    Zhang Da-Jian; Liu Chong-Long; Tong Dian-Min

    2015-01-01

    Many quantum systems of interest are initially correlated with their environments and the reduced dynamics of open systems are an interesting while challenging topic. Affine maps, as an extension of completely positive maps, are a useful tool to describe the reduced dynamics of open systems with initial correlations. However, it is unclear what kind of initial state shares an affine map. In this study, we give a sufficient condition of initial states, in which the reduced dynamics can always be described by an affine map. Our result shows that if the initial states of the combined system constitute a convex set, and if the correspondence between the initial states of the open system and those of the combined system, defined by taking the partial trace, is a bijection, then the reduced dynamics of the open system can be described by an affine map. (paper)

  11. DYNAMIC PROGRAMMING – EFFICIENT TOOL FOR POWER SYSTEM EXPANSION PLANNING

    Directory of Open Access Journals (Sweden)

    SIMO A.

    2015-03-01

    Full Text Available The paper isfocusing on dynamic programming use for power system expansion planning (EP – transmission network (TNEP and distribution network (DNEP. The EP problem has been approached from the retrospective and prospective point of view. To achieve this goal, the authors are developing two software-tools in Matlab environment. Two techniques have been tackled: particle swarm optimization (PSO and genetic algorithms (GA. The case study refers to Test 25 buses test power system developed within the Power Systems Department.

  12. Test report - caustic addition system operability test procedure

    International Nuclear Information System (INIS)

    Parazin, R.E.

    1995-01-01

    This Operability Test Report documents the test results of test procedure WHC-SD-WM-OTP-167 ''Caustic Addition System Operability Test Procedure''. The Objective of the test was to verify the operability of the 241-AN-107 Caustic Addition System. The objective of the test was met

  13. Recent developments in dynamic testing of materials

    Directory of Open Access Journals (Sweden)

    Seidt J.D.

    2012-08-01

    Full Text Available Three new testing configurations that have been developed since the last DYMAT conference in 2009 are presented. The first is high strain rate testing of Kevlar cloth and Kevlar yarn in a tensile Split Hopkinson Bar (SHB apparatus. The Kevlar cloth/yarn is attached to the bars by specially designed adaptors that keep the impedance constant. In addition to determining the specimen’s stress and strain from the recorded waves in the bars the deformations are also measured with Digital Image Correlation (DIC. The second testing configuration is a high strain rate shear test for sheet metal. The experiment is done by using a flat notched specimen in a tensile SHB apparatus. The shear strain is measured using DIC within the notch and on the boundary. The third development is a compression apparatus for testing at intermediate strain rates ranging from 20 s−1 to 200 s−1. The apparatus is a combination of a hydraulic actuator and a compression SHB. The stress in the specimen is determined from the stress wave in a very long transmitter bar and the strain and strain rate is determined by using DIC. The results show clean stress strain curves (no ringing.

  14. One testing method of dynamic linearity of an accelerometer

    Directory of Open Access Journals (Sweden)

    Lei Jing-Yu

    2015-01-01

    Full Text Available To effectively test dynamic linearity of an accelerometer over a wide rang of 104 g to about 20 × 104g, one published patent technology is first experimentally verified and analysed, and its deficient is presented, then based on stress wave propagation theory on the thin long bar, the relation between the strain signal and the corresponding acceleration signal is obtained, one special link of two coaxial projectile is developed. These two coaxial metal cylinders (inner cylinder and circular tube are used as projectiles, to prevent their mutual slip inside the gun barrel during movement, the one end of two projectiles is always fastened by small screws. Ti6-AL4-V bar with diameter of 30 mm is used to propagate loading stress pulse. The resultant compression wave can be measured by the strain gauges on the bar, and a half –sine strain pulse is obtained. The measuring accelerometer is attached on the other end of the bar by a vacuum clamp. In this clamp, the accelerometer only bear compression wave, the reflected tension pulse make the accelerometer off the bar. Using this system, dynamic linearity measurement of accelerometer can be easily tested in wider range of acceleration values. And a really measuring results are presented.

  15. Transcribing the balanced scorecard into system dynamics

    DEFF Research Database (Denmark)

    Nielsen, Steen; Nielsen, Erland Hejn

    2013-01-01

    The purpose of this paper is to show how a System Dynamics Modelling approach can be integrated into the Balanced Scorecard (BSC) for a case company with special focus on the handling of causality in a dynamic perspective. The BSC model includes five perspectives and a number of financial and non...... the cause-and-effect relationships of an integrated BSC model. Including dynamic aspects of BSCs into the discussion is only in its infancy, so the aim of our work is also to contribute to both scholars’ and practitioners’ general understanding of how such delayed dynamic effects propagate through system...

  16. Dynamical systems, attractors, and neural circuits.

    Science.gov (United States)

    Miller, Paul

    2016-01-01

    Biology is the study of dynamical systems. Yet most of us working in biology have limited pedagogical training in the theory of dynamical systems, an unfortunate historical fact that can be remedied for future generations of life scientists. In my particular field of systems neuroscience, neural circuits are rife with nonlinearities at all levels of description, rendering simple methodologies and our own intuition unreliable. Therefore, our ideas are likely to be wrong unless informed by good models. These models should be based on the mathematical theories of dynamical systems since functioning neurons are dynamic-they change their membrane potential and firing rates with time. Thus, selecting the appropriate type of dynamical system upon which to base a model is an important first step in the modeling process. This step all too easily goes awry, in part because there are many frameworks to choose from, in part because the sparsely sampled data can be consistent with a variety of dynamical processes, and in part because each modeler has a preferred modeling approach that is difficult to move away from. This brief review summarizes some of the main dynamical paradigms that can arise in neural circuits, with comments on what they can achieve computationally and what signatures might reveal their presence within empirical data. I provide examples of different dynamical systems using simple circuits of two or three cells, emphasizing that any one connectivity pattern is compatible with multiple, diverse functions.

  17. Error response test system and method using test mask variable

    Science.gov (United States)

    Gender, Thomas K. (Inventor)

    2006-01-01

    An error response test system and method with increased functionality and improved performance is provided. The error response test system provides the ability to inject errors into the application under test to test the error response of the application under test in an automated and efficient manner. The error response system injects errors into the application through a test mask variable. The test mask variable is added to the application under test. During normal operation, the test mask variable is set to allow the application under test to operate normally. During testing, the error response test system can change the test mask variable to introduce an error into the application under test. The error response system can then monitor the application under test to determine whether the application has the correct response to the error.

  18. Dynamic Mechanical Testing Techniques for Cortical and Cancellous Bone

    Science.gov (United States)

    Cloete, Trevor

    2017-06-01

    Bone fracture typically occurs as an impact loading event (sporting accidents, vehicle collisions), the simulation of which requires in-depth understanding of dynamic bone behavior. Bone is a natural composite material with a complex multi length-scale hierarchical microstructure. At a macroscopic level, it is classified into hard/compact cortical bone and soft/spongy cancellous (trabecular) bone, though both are low-impedance materials relative to steels. Cortical bone is predominant in long bones, while in complex bone geometries (joints, flat bones) a cancellous bone core supports a thin cortical shell. Bone has primarily been studied at quasi-static strain rates (ɛ˙ failure, with interrupted quasi-static tests revealing a strong microstructure dependence. However, bone specimens are typically destroyed during dynamic tests, leading to a lack of dynamic microstructural damage investigations. In this paper, a short overview of dynamic bone testing is presented to give context to the challenges of testing low impedance, strain-rate dependent, non-linear, visco-elastic-brittle materials. Recent state-of-the-art experimental developments in dynamic bone testing are reviewed, with emphasis on pulse shaping, momentum trapping and ISR testing. These techniques allow for dynamic bone testing at small strains and near-constant strain rates with intact specimen recovery. The results are compared to those obtained with varying strain rate tests. Interrupted dynamic test results with microstructural analysis of the recovered specimens are presented and discussed. The paper concludes with a discussion of the experimental and modeling challenges that lie ahead in the field of dynamic bone behavior. The financial assistance of the National Research Foundation and the University of Cape Town towards this research is hereby acknowledged. Opinions expressed and conclusions arrived at are those of the author alone.

  19. Multiloop integral system test (MIST)

    International Nuclear Information System (INIS)

    Gloudemans, J.R.

    1989-07-01

    The multiloop integral system test (MIST) was part of a multiphase program started in 1983 to address small-break loss-of-coolant accidents (SBLOCAs) specific to Babcock and Wilcox-designed plants. MIST was sponsored by the US Nuclear Regulatory Commission, the Babcock and Wilcox Owners Group, the Electric Power Research Institute, and Babcock and Wilcox. The unique features of the Babcock and Wilcox design, specifically the hot leg U-bends and steam generators, prevented the use of existing integral system data or existing integral system facilities to address the thermal-hydraulic SBLOCA questions. MIST and two other supporting facilities were specifically designed and constructed for this program, and an existing facility -- the once-through integral system (OTIS) -- was also used. Data from MIST and the other facilities will be used to benchmark the adequacy of system codes, such as RELAP5 and TRAC, for predicting abnormal plant transients. The individual tests are described in detail in Volumes 2 through 8 and Volume 11, and are summarized in Volume 1. Inter-group comparisons are addressed in this document, Volume 9. These comparisons are grouped as follows: mapping versus SBLOCA transients, SBLOCA, pump effects, and the effects of noncondensible gases. Appendix A provides an index and description of the microfiched plots for each test, which are enclosed with the corresponding Volumes 2 through 8. 147 figs., 5 tabs

  20. Puzzling with potential : dynamic testing of analogical reasoning in children

    NARCIS (Netherlands)

    Stevenson, Claire Elisabeth

    2012-01-01

    Assessment procedures are frequent in children's school careers; however, measuring potential for learning has remained a puzzle. Dynamic testing is a method to assess cognitive potential that includes training in the assessment process. The goal of this thesis project was to develop a new dynamic

  1. Optimal reduction of flexible dynamic system

    International Nuclear Information System (INIS)

    Jankovic, J.

    1994-01-01

    Dynamic system reduction is basic procedure in various problems of active control synthesis of flexible structures. In this paper is presented direct method for system reduction by explicit extraction of modes included in reduced model form. Criterion for optimal system discrete approximation in synthesis reduced dynamic model is also presented. Subjected method of system decomposition is discussed in relation to the Schur method of solving matrix algebraic Riccati equation as condition for system reduction. By using exposed method procedure of flexible system reduction in addition with corresponding example is presented. Shown procedure is powerful in problems of active control synthesis of flexible system vibrations

  2. Microcomputer based test system for charge coupled devices

    International Nuclear Information System (INIS)

    Sidman, S.

    1981-02-01

    A microcomputer based system for testing analog charge coupled integrated circuits has been developed. It measures device performance for three parameters: dynamic range, baseline shift due to leakage current, and transfer efficiency. A companion board tester has also been developed. The software consists of a collection of BASIC and assembly language routines developed on the test system microcomputer

  3. Reconstructing a nonlinear dynamical framework for testing quantum mechanics

    International Nuclear Information System (INIS)

    Jordan, T.F.

    1993-01-01

    The nonlinear generalization of quantum dynamics constructed by Weinberg as a basis for experimental tests is reconstructed in terms of density-matrix elements to allow independent dynamics for subsystems. Dynamics is generated with a Lie bracket and a nonlinear Hamiltonian function. It takes density matrices to density matrices and pure states to pure states. Each density matrix has a Hamiltonian operator that makes its evolution for an infinitesimal time, but the Hamiltonian operator may be different for different density matrices and may change in time as the density matrix changes. A Hamiltonian function for a subsystem serves also for the entire system. Independence of separate subsystems is confirmed by seeing that brackets are zero for functions from different subsystems and by looking at the Hamiltonian operator for each density matrix. Scaling properties of Hamiltonian functions are found to be important in connection with locality. An example of all this is obtained from every one of the local nonlinear Schroedinger equations described by Bialynicki-Birula and Mycielski. Examples are worked out for spins coupled together or to fields, demonstrating Hamiltonian functions and equations of motion written directly in terms of physical mean values. Observables and states are taken to be the same as in ordinary quantum mechanics. An attempt to find nonlinear representations of observables by characterizing propositions as functions equal to their squares yields a negative result. Sharper interpretation of mixed states is proposed. In a mixture of parts that are prepared separately, time dependence must be calculated separately for each part so different mixtures that yield the same density matrix can be distinguished. No criticism has shown that a consistent interpretation cannot be made this way. Thus, nonlinearity remains a viable hypothesis for experimental tests. 16 refs

  4. Dynamic analysis and qualification test of nuclear components

    International Nuclear Information System (INIS)

    Kim, B.K.; Lee, C.H.; Park, S.H.; Kim, Y.M.; Kim, B.S.; Kim, I.G.; Chung, C.W.; Kim, Y.M.

    1981-01-01

    This report contains the study on the dynamic characteristics of Wolsung fuel rod and on the dynamic balancing of rotating machinery to evaluate the performance of nuclear reactor components. The study on the dynamic characteristics of Wolsung fuel rod was carried out by both experimental and theoretical methods. Forced vibration testing of actual Wolsung fuel rod using sine sweep and sine dwell excitation was conducted to find the dynamic and nonlinear characteristics of the fuel rod. The data obtained by the test were used to analyze the nonlinear impact characteristics of the fuel rod which has a motion-constraint stop in the center of the rod. The parameters used in the test were the input force level of the exciter, the clearance gap between the fuel rod and the motion constraints, and the frequencies. Test results were in good agreement with the analytical results

  5. Seismic fragility test of a 6-inch diameter pipe system

    International Nuclear Information System (INIS)

    Chen, W.P.; Onesto, A.T.; DeVita, V.

    1987-02-01

    This report contains the test results and assessments of seismic fragility tests performed on a 6-inch diameter piping system. The test was funded by the US Nuclear Regulatory Commission (NRC) and conducted by ETEC. The objective of the test was to investigate the ability of a representative nuclear piping system to withstand high level dynamic seismic and other loadings. Levels of loadings achieved during seismic testing were 20 to 30 times larger than normal elastic design evaluations to ASME Level D limits would permit. Based on failure data obtained during seismic and other dynamic testing, it was concluded that nuclear piping systems are inherently able to withstand much larger dynamic seismic loadings than permitted by current design practice criteria or predicted by the probabilistic risk assessment (PRA) methods and several proposed nonlinear methods of failure analysis

  6. Stochastic Thermodynamics: A Dynamical Systems Approach

    Directory of Open Access Journals (Sweden)

    Tanmay Rajpurohit

    2017-12-01

    Full Text Available In this paper, we develop an energy-based, large-scale dynamical system model driven by Markov diffusion processes to present a unified framework for statistical thermodynamics predicated on a stochastic dynamical systems formalism. Specifically, using a stochastic state space formulation, we develop a nonlinear stochastic compartmental dynamical system model characterized by energy conservation laws that is consistent with statistical thermodynamic principles. In particular, we show that the difference between the average supplied system energy and the average stored system energy for our stochastic thermodynamic model is a martingale with respect to the system filtration. In addition, we show that the average stored system energy is equal to the mean energy that can be extracted from the system and the mean energy that can be delivered to the system in order to transfer it from a zero energy level to an arbitrary nonempty subset in the state space over a finite stopping time.

  7. Information Processing Capacity of Dynamical Systems

    Science.gov (United States)

    Dambre, Joni; Verstraeten, David; Schrauwen, Benjamin; Massar, Serge

    2012-07-01

    Many dynamical systems, both natural and artificial, are stimulated by time dependent external signals, somehow processing the information contained therein. We demonstrate how to quantify the different modes in which information can be processed by such systems and combine them to define the computational capacity of a dynamical system. This is bounded by the number of linearly independent state variables of the dynamical system, equaling it if the system obeys the fading memory condition. It can be interpreted as the total number of linearly independent functions of its stimuli the system can compute. Our theory combines concepts from machine learning (reservoir computing), system modeling, stochastic processes, and functional analysis. We illustrate our theory by numerical simulations for the logistic map, a recurrent neural network, and a two-dimensional reaction diffusion system, uncovering universal trade-offs between the non-linearity of the computation and the system's short-term memory.

  8. Information Processing Capacity of Dynamical Systems

    Science.gov (United States)

    Dambre, Joni; Verstraeten, David; Schrauwen, Benjamin; Massar, Serge

    2012-01-01

    Many dynamical systems, both natural and artificial, are stimulated by time dependent external signals, somehow processing the information contained therein. We demonstrate how to quantify the different modes in which information can be processed by such systems and combine them to define the computational capacity of a dynamical system. This is bounded by the number of linearly independent state variables of the dynamical system, equaling it if the system obeys the fading memory condition. It can be interpreted as the total number of linearly independent functions of its stimuli the system can compute. Our theory combines concepts from machine learning (reservoir computing), system modeling, stochastic processes, and functional analysis. We illustrate our theory by numerical simulations for the logistic map, a recurrent neural network, and a two-dimensional reaction diffusion system, uncovering universal trade-offs between the non-linearity of the computation and the system's short-term memory. PMID:22816038

  9. System Dynamics Modelling for a Balanced Scorecard

    DEFF Research Database (Denmark)

    Nielsen, Steen; Nielsen, Erland Hejn

    2008-01-01

    /methodology/approach - We use a case study model to develop time or dynamic dimensions by using a System Dynamics modelling (SDM) approach. The model includes five perspectives and a number of financial and non-financial measures. All indicators are defined and related to a coherent number of different cause...... have a major influence on other indicators and profit and may be impossible to predict without using a dynamic model. Practical implications - The model may be used as the first step in quantifying the cause-and-effect relationships of an integrated BSC model. Using the System Dynamics model provides......Purpose - To construct a dynamic model/framework inspired by a case study based on an international company. As described by the theory, one of the main difficulties of BSC is to foresee the time lag dimension of different types of indicators and their combined dynamic effects. Design...

  10. Modeling the Dynamic Digestive System Microbiome†

    OpenAIRE

    Estes, Anne M.

    2015-01-01

    “Modeling the Dynamic Digestive System Microbiome” is a hands-on activity designed to demonstrate the dynamics of microbiome ecology using dried pasta and beans to model disturbance events in the human digestive system microbiome. This exercise demonstrates how microbiome diversity is influenced by: 1) niche availability and habitat space and 2) a major disturbance event, such as antibiotic use. Students use a pictorial key to examine prepared models of digestive system microbiomes to determi...

  11. Dynamic Testing of Signal Transduction Deregulation During Breast Cancer Initiation

    Science.gov (United States)

    2012-07-01

    Std. Z39.18 Victoria Seewaldt, M.D. Dynamic Testing of Signal Transduction Deregulation During Breast Cancer Initiation Duke University Durham...attomole- zeptomole range. Internal dilution curves insure a high-dynamic calibration range. DU -26 8L DU -26 6L DU -29 5R DU -22 9.2 L DU...3: Nanobiosensor technology is translated to test for pathway deregulation in RPFNA cytology obtained from 10 high-risk women with cytological

  12. Session 6: Dynamic Modeling and Systems Analysis

    Science.gov (United States)

    Csank, Jeffrey; Chapman, Jeffryes; May, Ryan

    2013-01-01

    These presentations cover some of the ongoing work in dynamic modeling and dynamic systems analysis. The first presentation discusses dynamic systems analysis and how to integrate dynamic performance information into the systems analysis. The ability to evaluate the dynamic performance of an engine design may allow tradeoffs between the dynamic performance and operability of a design resulting in a more efficient engine design. The second presentation discusses the Toolbox for Modeling and Analysis of Thermodynamic Systems (T-MATS). T-MATS is a Simulation system with a library containing the basic building blocks that can be used to create dynamic Thermodynamic Systems. Some of the key features include Turbo machinery components, such as turbines, compressors, etc., and basic control system blocks. T-MAT is written in the Matlab-Simulink environment and is open source software. The third presentation focuses on getting additional performance from the engine by allowing the limit regulators only to be active when a limit is danger of being violated. Typical aircraft engine control architecture is based on MINMAX scheme, which is designed to keep engine operating within prescribed mechanical/operational safety limits. Using a conditionally active min-max limit regulator scheme, additional performance can be gained by disabling non-relevant limit regulators

  13. Dynamic tests on metallic impact limiters

    International Nuclear Information System (INIS)

    Sagartz, M.J.

    1978-01-01

    Three different types of metallic impact limiters were tested; plain fins, laterally stiffened fins and tubes whose axes were aligned with the direction of impact. All specimens were made of 304 stainless steel and were annealed before testing. A heavy steel drop table of variable mass and moving at about 13.4 m/s (44 ft/s) was used to impact the specimens which were mounted on a stationary base. Impact velocity, drop table acceleration vs. time and force vs. time were measured on each test and were used to calculate the energy absorbed by the impact limiters. Results showed that the peak stress that a plain fin can transmit to the cask body can be several times the static yield stress of the fin. Also as buckling proceeds the load in a plain fin drops significantly and the rate at which it absorbs energy falls off dramatically, making the fin a rather inefficient energy absorber overall. The laterally stiffened fin and the cylinders did not exhibit this rapid decrease in load-carrying capacity with deformation and hence were able to absorb relatively more energy per unit volume of material

  14. Experimental analyses of dynamical systems involving shape memory alloys

    DEFF Research Database (Denmark)

    Enemark, Søren; Savi, Marcelo A.; Santos, Ilmar F.

    2015-01-01

    The use of shape memory alloys (SMAs) in dynamical systems has an increasing importance in engineering especially due to their capacity to provide vibration reductions. In this regard, experimental tests are essential in order to show all potentialities of this kind of systems. In this work, SMA ...

  15. q-entropy for symbolic dynamical systems

    International Nuclear Information System (INIS)

    Zhao, Yun; Pesin, Yakov

    2015-01-01

    For symbolic dynamical systems we use the Carathéodory construction as described in (Pesin 1997 Dimension Theory in Dynamical Systems, ConTemporary Views and Applications (Chicago: University of Chicago Press)) to introduce the notions of q-topological and q-metric entropies. We describe some basic properties of these entropies and in particular, discuss relations between q-metric entropy and local metric entropy. Both q-topological and q-metric entropies are new invariants respectively under homeomorphisms and metric isomorphisms of dynamical systems. (paper)

  16. Planar dynamical systems selected classical problems

    CERN Document Server

    Liu, Yirong; Huang, Wentao

    2014-01-01

    This book presents in an elementary way the recent significant developments in the qualitative theory of planar dynamical systems. The subjects are covered as follows: the studies of center and isochronous center problems, multiple Hopf bifurcations and local and global bifurcations of the equivariant planar vector fields which concern with Hilbert's 16th problem. This book is intended for graduate students, post-doctors and researchers in the area of theories and applications of dynamical systems. For all engineers who are interested the theory of dynamical systems, it is also a reasona

  17. Collective Dynamics of Nonlinear and Disordered Systems

    CERN Document Server

    Radons, G; Just, W

    2005-01-01

    Phase transitions in disordered systems and related dynamical phenomena are a topic of intrinsically high interest in theoretical and experimental physics. This book presents a unified view, adopting concepts from each of the disjoint fields of disordered systems and nonlinear dynamics. Special attention is paid to the glass transition, from both experimental and theoretical viewpoints, to modern concepts of pattern formation, and to the application of the concepts of dynamical systems for understanding equilibrium and nonequilibrium properties of fluids and solids. The content is accessible to graduate students, but will also be of benefit to specialists, since the presentation extends as far as the topics of ongoing research work.

  18. SIAM conference on applications of dynamical systems

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    A conference (Oct.15--19, 1992, Snowbird, Utah; sponsored by SIAM (Society for Industrial and Applied Mathematics) Activity Group on Dynamical Systems) was held that highlighted recent developments in applied dynamical systems. The main lectures and minisymposia covered theory about chaotic motion, applications in high energy physics and heart fibrillations, turbulent motion, Henon map and attractor, integrable problems in classical physics, pattern formation in chemical reactions, etc. The conference fostered an exchange between mathematicians working on theoretical issues of modern dynamical systems and applied scientists. This two-part document contains abstracts, conference program, and an author index.

  19. The fractional dynamics of quantum systems

    Science.gov (United States)

    Lu, Longzhao; Yu, Xiangyang

    2018-05-01

    The fractional dynamic process of a quantum system is a novel and complicated problem. The establishment of a fractional dynamic model is a significant attempt that is expected to reveal the mechanism of fractional quantum system. In this paper, a generalized time fractional Schrödinger equation is proposed. To study the fractional dynamics of quantum systems, we take the two-level system as an example and derive the time fractional equations of motion. The basic properties of the system are investigated by solving this set of equations in the absence of light field analytically. Then, when the system is subject to the light field, the equations are solved numerically. It shows that the two-level system described by the time fractional Schrödinger equation we proposed is a confirmable system.

  20. Dynamics of mechanical systems with variable mass

    CERN Document Server

    Belyaev, Alexander

    2014-01-01

    The book presents up-to-date and unifying formulations for treating dynamics of different types of mechanical systems with variable mass. The starting point is overview of the continuum mechanics relations of balance and jump for open systems from which extended Lagrange and Hamiltonian formulations are derived. Corresponding approaches are stated at the level of analytical mechanics with emphasis on systems with a position-dependent mass and at the level of structural mechanics. Special emphasis is laid upon axially moving structures like belts and chains, and on pipes with an axial flow of fluid. Constitutive relations in the dynamics of systems with variable mass are studied with particular reference to modeling of multi-component mixtures. The dynamics of machines with a variable mass are treated in detail and conservation laws and the stability of motion will be analyzed. Novel finite element formulations for open systems in coupled fluid and structural dynamics are presented.

  1. Solar Dynamic Power System Stability Analysis and Control

    Science.gov (United States)

    Momoh, James A.; Wang, Yanchun

    1996-01-01

    The objective of this research is to conduct dynamic analysis, control design, and control performance test of solar power system. Solar power system consists of generation system and distribution network system. A bench mark system is used in this research, which includes a generator with excitation system and governor, an ac/dc converter, six DDCU's and forty-eight loads. A detailed model is used for modeling generator. Excitation system is represented by a third order model. DDCU is represented by a seventh order system. The load is modeled by the combination of constant power and constant impedance. Eigen-analysis and eigen-sensitivity analysis are used for system dynamic analysis. The effects of excitation system, governor, ac/dc converter control, and the type of load on system stability are discussed. In order to improve system transient stability, nonlinear ac/dc converter control is introduced. The direct linearization method is used for control design. The dynamic analysis results show that these controls affect system stability in different ways. The parameter coordination of controllers are recommended based on the dynamic analysis. It is concluded from the present studies that system stability is improved by the coordination of control parameters and the nonlinear ac/dc converter control stabilize system oscillation caused by the load change and system fault efficiently.

  2. Test computations on the dynamical evolution of star clusters

    International Nuclear Information System (INIS)

    Angeletti, L.; Giannone, P.

    1977-01-01

    Test calculations have been carried out on the evolution of star clusters using the fluid-dynamical method devised by Larson (1970). Large systems of stars have been considered with specific concern with globular clusters. With reference to the analogous 'standard' model by Larson, the influence of varying in turn the various free parameters (cluster mass, star mass, tidal radius, mass concentration of the initial model) has been studied for the results. Furthermore, the partial release of some simplifying assumptions with regard to the relaxation time and distribution of the 'target' stars has been considered. The change of the structural properties is discussed, and the variation of the evolutionary time scale is outlined. An indicative agreement of the results obtained here with structural properties of globular clusters as deduced from previous theoretical models is pointed out. (Auth.)

  3. Coherent regimes of globally coupled dynamical systems

    DEFF Research Database (Denmark)

    de Monte, Silvia; D'ovidio, Francesco; Mosekilde, Erik

    2003-01-01

    This Letter presents a method by which the mean field dynamics of a population of dynamical systems with parameter diversity and global coupling can be described in terms of a few macroscopic degrees of freedom. The method applies to populations of any size and functional form in the region...

  4. An Integrative Dynamical Systems Perspective on Emotions

    NARCIS (Netherlands)

    Treur, J.

    2013-01-01

    Within cognitive, affective and social neuroscience more and more mechanisms are found that suggest how emotions relate in a bidirectional manner to many other mental processes and behaviour. Based on this, in this paper a neurologically inspired dynamical systems approach on the dynamics and

  5. Induction Heating on Dynamic Tensile Tests in CEA Saclay

    International Nuclear Information System (INIS)

    Averty, X.; Yvon, P.; Duguay, C.; Pizzanelli, J. P.; Basini, V.

    2001-01-01

    The LCMI (Laboratory for characterization of irradiated materials), located in CEA from Saclay, is in charge of the mechanical tests on irradiated materials. The dynamic tensile testing machine, in a hot cell equipped with two remote handling, has been first improved in 1995, to fulfill the French safety programs on Reactivity Initiated Accident (RIA). One objective of this machine is to obtain mechanical property data on current Zircaloy cladding types needed to quality the cladding's response under RIA or LOCA transient loading and thermal conditions. For the RIA, this means testing at strain rates up to 5 s' and heating rates up to 200 degree centigree-s''-1, while for Loss of Coolant Accidents (LOCA) testing at strain rates of 10''-3 s''-1 and heating rates of 20 degree centigree s''-1 would be appropriate. The tensile samples are machined with a spark erosion machine, directly from pieces of cladding previously de fueled. Two kinds of samples can be machined in the cladding. Axial samples in order to test axial mechanical characteristics Ring samples in order to test transverse mechanical characteristics, more representative of RIA conditions. On one hand, the axial tensile tests were performed using the Joule effect, and heating rates up to about 500 degree centigree .s''-1 were obtained. This enabled us to perform the axial tests in a satisfactory manner. On the other hand, the tensile ring were first performed in a vertical furnace with a heating rate about 0.2 degree centigree.s''-1 and a thermal stability about 1 degree centigree. For temperatures above 480 degree centigree, the mechanical characteristics showed a sharp drop which could be attributed to irradiation defect annealing. Therefore we have recently developed an induction heating system to reach heating rates high enough (200 degree centigree.s''-1) to prevent any significant annealing before performing the ring tensile tests. To apply a uniaxial tangential tension, two matching half

  6. Regulation on control systems tests

    International Nuclear Information System (INIS)

    Grau, J.; Navarro, J.M.

    1978-01-01

    Requirements under regulation applicable to the testing of control systems and controlled equipments in the case of USA nuclear projects are examined. They are reviewed, in particular, the following standards and criteria: 10 Code of Federal Regulations 50, Appendix A, General Design Criteria 20 and 21; IEEE Standards 279 and 308; IEEE Standard 338; US Regulatory Guides 1.22 and 1.118.(J.E.de C.)

  7. Discriminating chaotic and stochastic dynamics through the permutation spectrum test

    Energy Technology Data Exchange (ETDEWEB)

    Kulp, C. W., E-mail: Kulp@lycoming.edu [Department of Astronomy and Physics, Lycoming College, Williamsport, Pennsylvania 17701 (United States); Zunino, L., E-mail: lucianoz@ciop.unlp.edu.ar [Centro de Investigaciones Ópticas (CONICET La Plata—CIC), C.C. 3, 1897 Gonnet (Argentina); Departamento de Ciencias Básicas, Facultad de Ingeniería, Universidad Nacional de La Plata (UNLP), 1900 La Plata (Argentina)

    2014-09-01

    In this paper, we propose a new heuristic symbolic tool for unveiling chaotic and stochastic dynamics: the permutation spectrum test. Several numerical examples allow us to confirm the usefulness of the introduced methodology. Indeed, we show that it is robust in situations in which other techniques fail (intermittent chaos, hyperchaotic dynamics, stochastic linear and nonlinear correlated dynamics, and deterministic non-chaotic noise-driven dynamics). We illustrate the applicability and reliability of this pragmatic method by examining real complex time series from diverse scientific fields. Taking into account that the proposed test has the advantages of being conceptually simple and computationally fast, we think that it can be of practical utility as an alternative test for determinism.

  8. Testing for significance of phase synchronisation dynamics in the EEG.

    Science.gov (United States)

    Daly, Ian; Sweeney-Reed, Catherine M; Nasuto, Slawomir J

    2013-06-01

    A number of tests exist to check for statistical significance of phase synchronisation within the Electroencephalogram (EEG); however, the majority suffer from a lack of generality and applicability. They may also fail to account for temporal dynamics in the phase synchronisation, regarding synchronisation as a constant state instead of a dynamical process. Therefore, a novel test is developed for identifying the statistical significance of phase synchronisation based upon a combination of work characterising temporal dynamics of multivariate time-series and Markov modelling. We show how this method is better able to assess the significance of phase synchronisation than a range of commonly used significance tests. We also show how the method may be applied to identify and classify significantly different phase synchronisation dynamics in both univariate and multivariate datasets.

  9. Magnetic test of chiral dynamics in QCD

    International Nuclear Information System (INIS)

    Simonov, Yu.A.

    2014-01-01

    Strong magnetic fields in the range eB≫m π 2 effectively probe internal quark structure of chiral mesons and test basic parameters of the chiral theory, such as 〈q-barq〉,f π . We argue on general grounds that 〈q-barq〉 should grow linearly with eB when charged quark degrees of freedom come into play. To make explicit estimates we extend the previously formulated chiral theory, including quark degrees of freedom, to the case of strong magnetic fields and show that the quark condensate |〈q-barq〉| u,d grows quadratically with eB for eB<0.2 GeV 2 and linearly for higher field values. These results agree quantitatively with recent lattice data and differ from χPT predictions

  10. Fracture toughness calculation using dynamic testing

    International Nuclear Information System (INIS)

    Perosanz, F. J.; Serrano, M.; Martinez, C.; Lapena, J.

    1998-01-01

    The most critical component of a Nuclear Power Station is the Reactor Pressure Vessel (RPV), due to safety and integrity requirements. The RPV is subjected to neutron radiation and this phenomenon lead to microstructural changes in the material and modifications in the mechanical properties. Due to this effects, it is necessary to assess the structural integrity of the RPV along the operational life through surveillance programs. The main objective of this surveillance programs is to determine the fracture toughness of the material. At present this objective is reached combining direct measures and prediction techniques. In this work, direct measures of fracture toughness using instrumented Charpy V impact testing are present using a CIEMAT development on analysis of results. (Author) 6 refs

  11. Dynamic testing of NOVA laser switchyard tower

    International Nuclear Information System (INIS)

    Weaver, H.J.; Pastrnak, J.W.; Fields, D.E.

    1984-01-01

    NOVA is the latest in a series of powerful laser systems designed to study the feasibility of initiating a controlled fusion reaction by concentrating several laser beams on a small fuel target. The laser components, turning mirrors and target chamber are all mounted on large steel frame structures. These structures were first analyzed via finite element models to access their seismic integrity as well as their overall vibrational stability. When construction was completed, a modal analysis was performed on the structures to verify and improve the finite element models. This report discusses the linking of the analytical and experimental studies for the NOVA switchyard tower structure

  12. Constraint Embedding for Multibody System Dynamics

    Science.gov (United States)

    Jain, Abhinandan

    2009-01-01

    This paper describes a constraint embedding approach for the handling of local closure constraints in multibody system dynamics. The approach uses spatial operator techniques to eliminate local-loop constraints from the system and effectively convert the system into tree-topology systems. This approach allows the direct derivation of recursive O(N) techniques for solving the system dynamics and avoiding the expensive steps that would otherwise be required for handling the closedchain dynamics. The approach is very effective for systems where the constraints are confined to small-subgraphs within the system topology. The paper provides background on the spatial operator O(N) algorithms, the extensions for handling embedded constraints, and concludes with some examples of such constraints.

  13. Understanding and Modeling Teams As Dynamical Systems

    Science.gov (United States)

    Gorman, Jamie C.; Dunbar, Terri A.; Grimm, David; Gipson, Christina L.

    2017-01-01

    By its very nature, much of teamwork is distributed across, and not stored within, interdependent people working toward a common goal. In this light, we advocate a systems perspective on teamwork that is based on general coordination principles that are not limited to cognitive, motor, and physiological levels of explanation within the individual. In this article, we present a framework for understanding and modeling teams as dynamical systems and review our empirical findings on teams as dynamical systems. We proceed by (a) considering the question of why study teams as dynamical systems, (b) considering the meaning of dynamical systems concepts (attractors; perturbation; synchronization; fractals) in the context of teams, (c) describe empirical studies of team coordination dynamics at the perceptual-motor, cognitive-behavioral, and cognitive-neurophysiological levels of analysis, and (d) consider the theoretical and practical implications of this approach, including new kinds of explanations of human performance and real-time analysis and performance modeling. Throughout our discussion of the topics we consider how to describe teamwork using equations and/or modeling techniques that describe the dynamics. Finally, we consider what dynamical equations and models do and do not tell us about human performance in teams and suggest future research directions in this area. PMID:28744231

  14. Dynamic Parameter-Control Chaotic System.

    Science.gov (United States)

    Hua, Zhongyun; Zhou, Yicong

    2016-12-01

    This paper proposes a general framework of 1-D chaotic maps called the dynamic parameter-control chaotic system (DPCCS). It has a simple but effective structure that uses the outputs of a chaotic map (control map) to dynamically control the parameter of another chaotic map (seed map). Using any existing 1-D chaotic map as the control/seed map (or both), DPCCS is able to produce a huge number of new chaotic maps. Evaluations and comparisons show that chaotic maps generated by DPCCS are very sensitive to their initial states, and have wider chaotic ranges, better unpredictability and more complex chaotic behaviors than their seed maps. Using a chaotic map of DPCCS as an example, we provide a field-programmable gate array design of this chaotic map to show the simplicity of DPCCS in hardware implementation, and introduce a new pseudo-random number generator (PRNG) to investigate the applications of DPCCS. Analysis and testing results demonstrate the excellent randomness of the proposed PRNG.

  15. Development of Test-Analysis Models (TAM) for correlation of dynamic test and analysis results

    Science.gov (United States)

    Angelucci, Filippo; Javeed, Mehzad; Mcgowan, Paul

    1992-01-01

    The primary objective of structural analysis of aerospace applications is to obtain a verified finite element model (FEM). The verified FEM can be used for loads analysis, evaluate structural modifications, or design control systems. Verification of the FEM is generally obtained as the result of correlating test and FEM models. A test analysis model (TAM) is very useful in the correlation process. A TAM is essentially a FEM reduced to the size of the test model, which attempts to preserve the dynamic characteristics of the original FEM in the analysis range of interest. Numerous methods for generating TAMs have been developed in the literature. The major emphasis of this paper is a description of the procedures necessary for creation of the TAM and the correlation of the reduced models with the FEM or the test results. Herein, three methods are discussed, namely Guyan, Improved Reduced System (IRS), and Hybrid. Also included are the procedures for performing these analyses using MSC/NASTRAN. Finally, application of the TAM process is demonstrated with an experimental test configuration of a ten bay cantilevered truss structure.

  16. Solved problems in dynamical systems and control

    CERN Document Server

    Tenreiro-Machado, J; Valério, Duarte; Galhano, Alexandra M

    2016-01-01

    This book presents a collection of exercises on dynamical systems, modelling and control. Each topic covered includes a summary of the theoretical background, problems with solutions, and further exercises.

  17. Scoping Future Policy Dynamics in Raw Materials Through Scenarios Testing

    Science.gov (United States)

    Correia, Vitor; Keane, Christopher; Sturm, Flavius; Schimpf, Sven; Bodo, Balazs

    2017-04-01

    The International Raw Materials Observatory (INTRAW) project is working towards a sustainable future for the European Union in access to raw materials, from an availability, economical, and environmental framework. One of the major exercises for the INTRAW project is the evaluation of potential future scenarios for 2050 to frame economic, research, and environmental policy towards a sustainable raw materials supply. The INTRAW consortium developed three possible future scenarios that encompass defined regimes of political, economic, and technological norms. The first scenario, "Unlimited Trade," reflects a world in which free trade continues to dominate the global political and economic environment, with expectations of a growing demand for raw materials from widely distributed global growth. The "National Walls" scenario reflects a world where nationalism and economic protectionism begins to dominate, leading to stagnating economic growth and uneven dynamics in raw materials supply and demand. The final scenario, "Sustainability Alliance," examines the dynamics of a global political and economic climate that is focused on environmental and economic sustainability, leading towards increasingly towards a circular raw materials economy. These scenarios were reviewed, tested, and provided simulations of impacts with members of the Consortium and a panel of global experts on international raw materials issues which led to expected end conditions for 2050. Given the current uncertainty in global politics, these scenarios are informative to identifying likely opportunities and crises. The details of these simulations and expected responses to the research demand, technology investments, and economic components of raw materials system will be discussed.

  18. Dynamical Systems Approach to Endothelial Heterogeneity

    Science.gov (United States)

    Regan, Erzsébet Ravasz; Aird, William C.

    2012-01-01

    Rationale Objective Here we reexamine our current understanding of the molecular basis of endothelial heterogeneity. We introduce multistability as a new explanatory framework in vascular biology. Methods We draw on the field of non-linear dynamics to propose a dynamical systems framework for modeling multistability and its derivative properties, including robustness, memory, and plasticity. Conclusions Our perspective allows for both a conceptual and quantitative description of system-level features of endothelial regulation. PMID:22723222

  19. Nonlinear and Complex Dynamics in Real Systems

    OpenAIRE

    William Barnett; Apostolos Serletis; Demitre Serletis

    2005-01-01

    This paper was produced for the El-Naschie Symposium on Nonlinear Dynamics in Shanghai in December 2005. In this paper we provide a review of the literature with respect to fluctuations in real systems and chaos. In doing so, we contrast the order and organization hypothesis of real systems with nonlinear chaotic dynamics and discuss some techniques used in distinguishing between stochastic and deterministic behavior. Moreover, we look at the issue of where and when the ideas of chaos could p...

  20. PASLINK and dynamic outdoor testing of building components

    NARCIS (Netherlands)

    Baker, P.H.; Dijk, H.A.L. van

    2008-01-01

    The PASLINK test facilities and analysis procedures aim to obtain the thermal and solar characteristics of building components under real dynamic outdoor conditions. Both the analysis and the test methodology have evolved since the start of the PASSYS Project in 1985. A programme of upgrading the

  1. Dynamic Double Curvature Mould System

    DEFF Research Database (Denmark)

    Jepsen, Christian Raun; Kristensen, Mathias Kræmmergaard; Kirkegaard, Poul Henning

    2011-01-01

    The present paper describes a concept for a reconfigurable mould surface which is designed to fit the needs of contemporary architecture. The core of the concept presented is a dynamic surface manipulated into a given shape using a digital signal created directly from the CAD drawing of the design....... This happens fast, automatic and without production of waste, and the manipulated surface is fair and robust, eliminating the need for additional, manual treatment. Limitations to the possibilities of the flexible form are limited curvature and limited level of detail, making it especially suited for larger...

  2. Attractors and basins of dynamical systems

    Directory of Open Access Journals (Sweden)

    Attila Dénes

    2011-03-01

    Full Text Available There are several programs for studying dynamical systems, but none of them is very useful for investigating basins and attractors of higher dimensional systems. Our goal in this paper is to show a new algorithm for finding even chaotic attractors and their basins for these systems. We present an implementation and examples for the use of this program.

  3. The brain as a dynamic physical system.

    Science.gov (United States)

    McKenna, T M; McMullen, T A; Shlesinger, M F

    1994-06-01

    The brain is a dynamic system that is non-linear at multiple levels of analysis. Characterization of its non-linear dynamics is fundamental to our understanding of brain function. Identifying families of attractors in phase space analysis, an approach which has proven valuable in describing non-linear mechanical and electrical systems, can prove valuable in describing a range of behaviors and associated neural activity including sensory and motor repertoires. Additionally, transitions between attractors may serve as useful descriptors for analysing state changes in neurons and neural ensembles. Recent observations of synchronous neural activity, and the emerging capability to record the spatiotemporal dynamics of neural activity by voltage-sensitive dyes and electrode arrays, provide opportunities for observing the population dynamics of neural ensembles within a dynamic systems context. New developments in the experimental physics of complex systems, such as the control of chaotic systems, selection of attractors, attractor switching and transient states, can be a source of powerful new analytical tools and insights into the dynamics of neural systems.

  4. Dynamics and control of technical systems

    CERN Document Server

    Balthazar, José M; Kaczmarczyk, Stefan

    2014-01-01

    The main topics of this Special Issue are linear and, mainly, nonlinear dynamics, chaos and control of systems and structures and their applications in different field of science and engineering. According to the goal of the Special Issue, the selected contributions are divided into three major parts: ""Vibration Problems in Vertical Transportation Systems"", ""Nonlinear Dynamics, Chaos and Control of Elastic Structures"" and ""New Strategies and Challenges for Aerospace and Ocean Structures Dynamics and Control"". The discussion of real problems in aerospace and how these problems can be unde

  5. Dynamics of the diffusive DM-DE interaction – Dynamical system approach

    Energy Technology Data Exchange (ETDEWEB)

    Haba, Zbigniew [Institute of Theoretical Physics, University of Wroclaw, Plac Maxa Borna 9, 50-204 Wrocław (Poland); Stachowski, Aleksander; Szydłowski, Marek, E-mail: zhab@ift.uni.wroc.pl, E-mail: aleksander.stachowski@uj.edu.pl, E-mail: marek.szydlowski@uj.edu.pl [Astronomical Observatory, Jagiellonian University, Orla 171, 30-244 Krakow (Poland)

    2016-07-01

    We discuss dynamics of a model of an energy transfer between dark energy (DE) and dark matter (DM) . The energy transfer is determined by a non-conservation law resulting from a diffusion of dark matter in an environment of dark energy. The relativistic invariance defines the diffusion in a unique way. The system can contain baryonic matter and radiation which do not interact with the dark sector. We treat the Friedman equation and the conservation laws as a closed dynamical system. The dynamics of the model is examined using the dynamical systems methods for demonstration how solutions depend on initial conditions. We also fit the model parameters using astronomical observation: SNIa, H ( z ), BAO and Alcock-Paczynski test. We show that the model with diffuse DM-DE is consistent with the data.

  6. Dynamical systems examples of complex behaviour

    CERN Document Server

    Jost, Jürgen

    2005-01-01

    Our aim is to introduce, explain, and discuss the fundamental problems, ideas, concepts, results, and methods of the theory of dynamical systems and to show how they can be used in speci?c examples. We do not intend to give a comprehensive overview of the present state of research in the theory of dynamical systems, nor a detailed historical account of its development. We try to explain the important results, often neglecting technical re?nements 1 and, usually, we do not provide proofs. One of the basic questions in studying dynamical systems, i.e. systems that evolve in time, is the construction of invariants that allow us to classify qualitative types of dynamical evolution, to distinguish between qualitatively di?erent dynamics, and to studytransitions between di?erent types. Itis also important to ?nd out when a certain dynamic behavior is stable under small perturbations, as well as to understand the various scenarios of instability. Finally, an essential aspect of a dynamic evolution is the transformat...

  7. Dynamic testing in schizophrenia: does training change the construct validity of a test?

    Science.gov (United States)

    Wiedl, Karl H; Schöttke, Henning; Green, Michael F; Nuechterlein, Keith H

    2004-01-01

    Dynamic testing typically involves specific interventions for a test to assess the extent to which test performance can be modified, beyond level of baseline (static) performance. This study used a dynamic version of the Wisconsin Card Sorting Test (WCST) that is based on cognitive remediation techniques within a test-training-test procedure. From results of previous studies with schizophrenia patients, we concluded that the dynamic and static versions of the WCST should have different construct validity. This hypothesis was tested by examining the patterns of correlations with measures of executive functioning, secondary verbal memory, and verbal intelligence. Results demonstrated a specific construct validity of WCST dynamic (i.e., posttest) scores as an index of problem solving (Tower of Hanoi) and secondary verbal memory and learning (Auditory Verbal Learning Test), whereas the impact of general verbal capacity and selective attention (Verbal IQ, Stroop Test) was reduced. It is concluded that the construct validity of the test changes with dynamic administration and that this difference helps to explain why the dynamic version of the WCST predicts functional outcome better than the static version.

  8. Dynamic flow control strategies of vehicle SCR Urea Dosing System

    Science.gov (United States)

    Lin, Wei; Zhang, Youtong; Asif, Malik

    2015-03-01

    Selective Catalyst Reduction(SCR) Urea Dosing System(UDS) directly affects the system accuracy and the dynamic response performance of a vehicle. However, the UDS dynamic response is hard to keep up with the changes of the engine's operating conditions. That will lead to low NO X conversion efficiency or NH3 slip. In order to optimize the injection accuracy and the response speed of the UDS in dynamic conditions, an advanced control strategy based on an air-assisted volumetric UDS is presented. It covers the methods of flow compensation and switching working conditions. The strategy is authenticated on an UDS and tested in different dynamic conditions. The result shows that the control strategy discussed results in higher dynamic accuracy and faster dynamic response speed of UDS. The inject deviation range is improved from being between -8% and 10% to -4% and 2% and became more stable than before, and the dynamic response time was shortened from 200 ms to 150 ms. The ETC cycle result shows that after using the new strategy the NH3 emission is reduced by 60%, and the NO X emission remains almost unchanged. The trade-off between NO X conversion efficiency and NH3 slip is mitigated. The studied flow compensation and switching working conditions can improve the dynamic performance of the UDS significantly and make the UDS dynamic response keep up with the changes of the engine's operating conditions quickly.

  9. Lectures on fractal geometry and dynamical systems

    CERN Document Server

    Pesin, Yakov

    2009-01-01

    Both fractal geometry and dynamical systems have a long history of development and have provided fertile ground for many great mathematicians and much deep and important mathematics. These two areas interact with each other and with the theory of chaos in a fundamental way: many dynamical systems (even some very simple ones) produce fractal sets, which are in turn a source of irregular "chaotic" motions in the system. This book is an introduction to these two fields, with an emphasis on the relationship between them. The first half of the book introduces some of the key ideas in fractal geometry and dimension theory--Cantor sets, Hausdorff dimension, box dimension--using dynamical notions whenever possible, particularly one-dimensional Markov maps and symbolic dynamics. Various techniques for computing Hausdorff dimension are shown, leading to a discussion of Bernoulli and Markov measures and of the relationship between dimension, entropy, and Lyapunov exponents. In the second half of the book some examples o...

  10. System dynamics an introduction for mechanical engineers

    CERN Document Server

    Seeler, Karl A

    2014-01-01

    This essential textbook takes the student from the initial steps in modeling a dynamic system through development of the mathematical models needed for feedback control.  The generously-illustrated, student-friendly text focuses on fundamental theoretical development rather than the application of commercial software.  Practical details of machine design are included to motivate the non-mathematically inclined student. This book also: Emphasizes the linear graph method for modeling dynamic systems Offers a systematic approach for creating an engineering model, extracting information, and formulating mathematical analyses Adopts a unifying theme of power flow as the dynamic agent that eases analysis of hybrid systems, such as machinery Presents differential equations as dynamic operators and stresses input/output relationships Introduces Mathcad and programming in MATLAB Allows for use of Open Source Computational Software (R or C) Features over 1000 illustrations

  11. Dynamic memory management for embedded systems

    CERN Document Server

    Atienza Alonso, David; Poucet, Christophe; Peón-Quirós, Miguel; Bartzas, Alexandros; Catthoor, Francky; Soudris, Dimitrios

    2015-01-01

    This book provides a systematic and unified methodology, including basic principles and reusable processes, for dynamic memory management (DMM) in embedded systems.  The authors describe in detail how to design and optimize the use of dynamic memory in modern, multimedia and network applications, targeting the latest generation of portable embedded systems, such as smartphones. Coverage includes a variety of design and optimization topics in electronic design automation of DMM, from high-level software optimization to microarchitecture-level hardware support. The authors describe the design of multi-layer dynamic data structures for the final memory hierarchy layers of the target portable embedded systems and how to create a low-fragmentation, cost-efficient, dynamic memory management subsystem out of configurable components for the particular memory allocation and de-allocation patterns for each type of application.  The design methodology described in this book is based on propagating constraints among de...

  12. The design of brake fatigue testing system

    Directory of Open Access Journals (Sweden)

    Huang, Xiaoya

    2015-01-01

    Full Text Available Brake is used to reduce the operating speed of the machinery equipment or to make it stop. It is essential for vehicles, climbing machines and many fixed equipment in their safety work. Brake tester is an experimental apparatus to measure and analyse the braking performance. Based on the PLC technology and for the purpose of testing brake shoe friction material’s life, this paper designed a virtual brake test platform. In it, inverter were used to control the motor, so that it can load automatically and ensure brake drum constant speed output; what is more, closed loop control system were used to control the brake shoe, so that the cylinder pressure keeps stable in the process of dynamic braking.

  13. Role of quantitative and dynamic radioactive studies in renal testing

    International Nuclear Information System (INIS)

    Raynaud, C.

    1977-01-01

    Many dynamic and quantitative radioactive tests are at present used in studying renal function. Whether involving dynamic morphological tests such as sequential images, dynamic quantitative tests such as the renogram or quantitative static tests such as radioactive clearances, their effective and original contribution is rather unimportant. Only one provides original data, the Hg renal uptake test but it is generally avoided due to the radiation dose absorbed by the kidney in children. A study of the causes of this lack of effectiveness leads to the observation that such tests are not well adapted to the needs of kidneys specialists. They are for the most part based on replacing a 'cold' indicator by radioactive indicator and the advantages anticipated from using radionuclide are not evident. In fact, they are often cancelled by the shortcomings of external detection. For the future, it seems indispensable to abandon some traditional concepts which lead us to consider that the only exploitable renal function is represented by excretion. The kidney has other functions; one of the most interesting seems to be the function of uptake of heavy metals and toxic substances, a study of which is only possible using radionuclides. A new generation of radioactive tests based on a study of uptake and also on a study of other renal functions may provide dynamic or quantitative data which physician urgently need

  14. System crash as dynamics of complex networks.

    Science.gov (United States)

    Yu, Yi; Xiao, Gaoxi; Zhou, Jie; Wang, Yubo; Wang, Zhen; Kurths, Jürgen; Schellnhuber, Hans Joachim

    2016-10-18

    Complex systems, from animal herds to human nations, sometimes crash drastically. Although the growth and evolution of systems have been extensively studied, our understanding of how systems crash is still limited. It remains rather puzzling why some systems, appearing to be doomed to fail, manage to survive for a long time whereas some other systems, which seem to be too big or too strong to fail, crash rapidly. In this contribution, we propose a network-based system dynamics model, where individual actions based on the local information accessible in their respective system structures may lead to the "peculiar" dynamics of system crash mentioned above. Extensive simulations are carried out on synthetic and real-life networks, which further reveal the interesting system evolution leading to the final crash. Applications and possible extensions of the proposed model are discussed.

  15. Electromagnetic Environmental Effects System Testing

    Science.gov (United States)

    2013-11-20

    localized ( spot ) illumination is adequate to evaluate potential responses by illuminating specific apertures, cables and subsystems. At these...the EMC testing. The Battlefield Functional Area Control System (BFACS), Force XXI Blue Force Tracker (BFT), routers, hubs, switches, etc, are... Laser Printer F1 F1 F1 G G G G G G G G G G G G G G G G G G G G G G G G G G Embedded Training Module F1 F1 F1 G G G G G G G G G G G G G G G G G G G G G

  16. Modular interdependency in complex dynamical systems.

    Science.gov (United States)

    Watson, Richard A; Pollack, Jordan B

    2005-01-01

    Herbert A. Simon's characterization of modularity in dynamical systems describes subsystems as having dynamics that are approximately independent of those of other subsystems (in the short term). This fits with the general intuition that modules must, by definition, be approximately independent. In the evolution of complex systems, such modularity may enable subsystems to be modified and adapted independently of other subsystems, whereas in a nonmodular system, modifications to one part of the system may result in deleterious side effects elsewhere in the system. But this notion of modularity and its effect on evolvability is not well quantified and is rather simplistic. In particular, modularity need not imply that intermodule dependences are weak or unimportant. In dynamical systems this is acknowledged by Simon's suggestion that, in the long term, the dynamical behaviors of subsystems do interact with one another, albeit in an "aggregate" manner--but this kind of intermodule interaction is omitted in models of modularity for evolvability. In this brief discussion we seek to unify notions of modularity in dynamical systems with notions of how modularity affects evolvability. This leads to a quantifiable measure of modularity and a different understanding of its effect on evolvability.

  17. X-ray testing for short-time dynamic applications

    International Nuclear Information System (INIS)

    Kurfiss, Malte; Moser, Stefan; Popko, Gregor; Nau, Siegfried

    2017-01-01

    For nondestructive testing purposes new challenges are short-time dynamic processes. The application of x-ray flash tubes and modern high-speed cameras allows the observation of the opening of air-bags or the energy absorption of compressed tubes as occurring during a vehicle crash. Special algorithms designed for computerized tomography analyses allow the 3D reconstruction at individual time points of the dynamic process. Possibilities and limitations of the actual techniques are discussed.

  18. Final test report: demonsration testing in support of the Track 3system waste dislodging, retrieval and conveyance concepts

    Energy Technology Data Exchange (ETDEWEB)

    Berglin, E.J.

    1997-07-24

    This report contains the quantitative and qualitative data and information collected during performance of the Track 3 System testing protocol. Information contained herein focuses on the data collected during performance ofthe following Tests Procedures. *Test Procedure-1, Position Management Test Procedure-2, Waste Dislodging, Retrieval, and Conveyance and Decontamination *Test Procedure-3, Dynamic Response Test procedures, Safety Demonstration

  19. Final test report: demonstration testing in support of the Track 3system waste dislodging, retrieval and conveyance concepts

    International Nuclear Information System (INIS)

    Berglin, E.J.

    1997-01-01

    This report contains the quantitative and qualitative data and information collected during performance of the Track 3 System testing protocol. Information contained herein focuses on the data collected during performance of the following Tests Procedures. *Test Procedure-1, Position Management Test Procedure-2, Waste Dislodging, Retrieval, and Conveyance and Decontamination *Test Procedure-3, Dynamic Response Test procedures, Safety Demonstration

  20. Dynamics of the solar system

    International Nuclear Information System (INIS)

    Sidlichovsky, M.

    1987-01-01

    The conference proceedings contains a total of 31 papers of which 7 have not been incorporated in INIS. The papers mainly discuss the mathematical methods of calculating the movement of planets, their satellites and asteroids in the solar system and the mathematical modelling of the past development of the solar system. Great attention is also devoted to resonance in the solar system and to the study of many celestial bodies. Four papers are devoted to planetary rings and three to modern astrometry. (M.D.). 63 figs., 10 tabs., 520 refs

  1. Extreme loads seismic testing of conduit systems

    International Nuclear Information System (INIS)

    Howard, G.E.; Ibanez, P.; Harrison, S.; Shi, Z.T.

    1991-01-01

    Rigid steel conduit (thin-wall tubes with threaded connections) containing electrical cabling are a common feature in nuclear power plants. Conduit systems are in many cases classified in U.S.A. practice as Seismic Category I structures. this paper summarizes results and others aspects of a dynamic test program conducted to investigate conduit systems seismic performance under three-axis excitation for designs representative at a nuclear power plant sited near Ft. Worth, Texas (a moderate seismic zone), with a Safe Shutdown Earthquake (SSE) of 0.12 g. Test specimens where subjected to postulated seismic events, including excitation well in excess of Safe Shutdown Earthquake events typical for U.S.A. nuclear power stations. A total of 18 conduit systems of 9-meter nominal lengths were shake table mounted and subjected to a variety of tests. None of the specimens suffered loss of load capacity when subjected to a site-enveloping Safe Shutdown Earthquake (SSE). Clamp/attachment hardware failures only began to occur when earthquake input motion was scaled upward to minimum values of 2.3-4.6 times site enveloping SSE response spectra. Tensile and/or shear failure of clamp attachment bolts or studs was the failure mode in all case in which failure was induced. (author)

  2. Dynamic cell culture system (7-IML-1)

    Science.gov (United States)

    Cogoli, Augusto

    1992-01-01

    This experiment is one of the Biorack experiments being flown on the International Microgravity Laboratory 1 (MIL-1) mission as part of an investigation studying cell proliferation and performance in space. One of the objectives of this investigation is to assess the potential benefits of bioprocessing in space with the ultimate goal of developing a bioreactor for continuous cell cultures in space. This experiment will test the operation of an automated culture chamber that was designed for use in a Bioreactor in space. The device to be tested is called the Dynamic Cell Culture System (DCCS). It is a simple device in which media are renewed or chemicals are injected automatically, by means of osmotic pumps. This experiment uses four Type I/O experiment containers. One DCCS unit, which contains a culture chamber with renewal of medium and a second chamber without a medium supply fits in each container. Two DCCS units are maintained under zero gravity conditions during the on-orbit period. The other two units are maintained under 1 gh conditions in a 1 g centrifuge. The schedule for incubator transfer is given.

  3. Quantum Dynamics of Test Particle in Curved Space-Time

    International Nuclear Information System (INIS)

    Piechocki, W.

    2002-01-01

    To reveal the nature of space-time singularities of removable type we examine classical and quantum dynamics of a free particle in the Sitter type spacetimes. Consider space-times have different topologies otherwise are isometric. Our systems are integrable and we present analytic solutions of the classical dynamics. We quantize the systems by making use of the group theoretical method: we find an essentially self-adjoint representation of the algebra of observables integrable to the irreducible unitarity representation of the symmetry group of each consider gravitational system. The massless particle dynamics is obtained in the zero-mass limit of the massive case. Global properties of considered gravitational systems are of primary importance for the quantization procedure. Systems of a particle in space-times with removable singularities appear to be quantizable. We give specific proposal for extension of our analysis to space-times with essential type singularities. (author)

  4. Dynamics of Multibody Systems Near Lagrangian Points

    Science.gov (United States)

    Wong, Brian

    This thesis examines the dynamics of a physically connected multi-spacecraft system in the vicinity of the Lagrangian points of a Circular Restricted Three-Body System. The spacecraft system is arranged in a wheel-spoke configuration with smaller and less massive satellites connected to a central hub using truss/beams or tether connectors. The kinematics of the system is first defined, and the kinetic, gravitational potential energy and elastic potential energy of the system are derived. The Assumed Modes Method is used to discretize the continuous variables of the system, and a general set of ordinary differential equations describing the dynamics of the connectors and the central hub are obtained using the Lagrangian method. The flexible body dynamics of the tethered and truss connected systems are examined using numerical simulations. The results show that these systems experienced only small elastic deflections when they are naturally librating or rotating at moderate angular velocities, and these deflections have relatively small effect on the attitude dynamics of the systems. Based on these results, it is determined that the connectors can be modeled as rigid when only the attitude dynamics of the system is of interest. The equations of motion of rigid satellites stationed at the Lagrangian points are linearized, and the stability conditions of the satellite are obtained from the linear equations. The required conditions are shown to be similar to those of geocentric satellites. Study of the linear equations also revealed the resonant conditions of rigid Lagrangian point satellites, when a librational natural frequency of the satellite matches the frequency of its station-keeping orbit leading to large attitude motions. For tethered satellites, the linear analysis shows that the tethers are in stable equilibrium when they lie along a line joining the two primary celestial bodies of the Three-Body System. Numerical simulations are used to study the long term

  5. A review of dynamic characteristics of magnetically levitated vehicle systems

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Y.; Chen, S.S.

    1995-11-01

    The dynamic response of magnetically levitated (maglev) ground transportation systems has important consequences for safety and ride quality, guideway design, and system costs. Ride quality is determined by vehicle response and by environmental factors such as humidity and noise. The dynamic response of the vehicles is the key element in determining ride quality, while vehicle stability is an important safety-related element. To design a guideway that provides acceptable ride quality in the stable region, vehicle dynamics must be understood. Furthermore, the trade-off between guideway smoothness and levitation and control systems must be considered if maglev systems are to be economically feasible. The link between the guideway and the other maglev components is vehicle dynamics. For a commercial maglev system, vehicle dynamics must be analyzed and tested in detail. This report, which reviews various aspects of the dynamic characteristics, experiments and analysis, and design guidelines for maglev systems, discusses vehicle stability, motion dependent magnetic force components, guideway characteristics, vehicle/ guideway interaction, ride quality, suspension control laws, aerodynamic loads and other excitations, and research needs.

  6. Hybrid dynamical systems observation and control

    CERN Document Server

    Defoort, Michael

    2015-01-01

    This book is a collection of contributions defining the state of current knowledge and new trends in hybrid systemssystems involving both continuous dynamics and discrete events – as described by the work of several well-known groups of researchers. Hybrid Dynamical Systems presents theoretical advances in such areas as diagnosability, observability and stabilization for various classes of system. Continuous and discrete state estimation and self-triggering control of nonlinear systems are advanced. The text employs various methods, among them, high-order sliding modes, Takagi–Sugeno representation and sampled-data switching to achieve its ends. The many applications of hybrid systems from power converters to computer science are not forgotten; studies of flexible-joint robotic arms and – as representative biological systems – the behaviour of the human heart and vasculature, demonstrate the wide-ranging practical significance of control in hybrid systems. The cross-disciplinary origins of study ...

  7. Dynamic Calibration and Verification Device of Measurement System for Dynamic Characteristic Coefficients of Sliding Bearing

    Science.gov (United States)

    Chen, Runlin; Wei, Yangyang; Shi, Zhaoyang; Yuan, Xiaoyang

    2016-01-01

    The identification accuracy of dynamic characteristics coefficients is difficult to guarantee because of the errors of the measurement system itself. A novel dynamic calibration method of measurement system for dynamic characteristics coefficients is proposed in this paper to eliminate the errors of the measurement system itself. Compared with the calibration method of suspension quality, this novel calibration method is different because the verification device is a spring-mass system, which can simulate the dynamic characteristics of sliding bearing. The verification device is built, and the calibration experiment is implemented in a wide frequency range, in which the bearing stiffness is simulated by the disc springs. The experimental results show that the amplitude errors of this measurement system are small in the frequency range of 10 Hz–100 Hz, and the phase errors increase along with the increasing of frequency. It is preliminarily verified by the simulated experiment of dynamic characteristics coefficients identification in the frequency range of 10 Hz–30 Hz that the calibration data in this frequency range can support the dynamic characteristics test of sliding bearing in this frequency range well. The bearing experiments in greater frequency ranges need higher manufacturing and installation precision of calibration device. Besides, the processes of calibration experiments should be improved. PMID:27483283

  8. Problems of classical dynamical systems

    International Nuclear Information System (INIS)

    Thirring, W.

    1975-01-01

    After a brief survey of Hamiltonian theory and of relevant notions of set theory and manifolds, these lecture notes present some general properties of orbits, paying special attention to integrable systems. This is followed by a discussion of the Kolmogorov-Arnol'd-Moser theorem, dealing with the stability of orbits under small perturbations, and its importance for ergodic theory. Ergodicity and mixing are then treated in detail. In particular, the ergodic theorem of von Neumann is derived, and a specific example is given of a (strongly) mixing system. (author)

  9. Topological theory of dynamical systems recent advances

    CERN Document Server

    Aoki, N

    1994-01-01

    This monograph aims to provide an advanced account of some aspects of dynamical systems in the framework of general topology, and is intended for use by interested graduate students and working mathematicians. Although some of the topics discussed are relatively new, others are not: this book is not a collection of research papers, but a textbook to present recent developments of the theory that could be the foundations for future developments. This book contains a new theory developed by the authors to deal with problems occurring in diffentiable dynamics that are within the scope of general topology. To follow it, the book provides an adequate foundation for topological theory of dynamical systems, and contains tools which are sufficiently powerful throughout the book. Graduate students (and some undergraduates) with sufficient knowledge of basic general topology, basic topological dynamics, and basic algebraic topology will find little difficulty in reading this book.

  10. Controllable Subspaces of Open Quantum Dynamical Systems

    International Nuclear Information System (INIS)

    Zhang Ming; Gong Erling; Xie Hongwei; Hu Dewen; Dai Hongyi

    2008-01-01

    This paper discusses the concept of controllable subspace for open quantum dynamical systems. It is constructively demonstrated that combining structural features of decoherence-free subspaces with the ability to perform open-loop coherent control on open quantum systems will allow decoherence-free subspaces to be controllable. This is in contrast to the observation that open quantum dynamical systems are not open-loop controllable. To a certain extent, this paper gives an alternative control theoretical interpretation on why decoherence-free subspaces can be useful for quantum computation.

  11. Linear dynamic coupling in geared rotor systems

    Science.gov (United States)

    David, J. W.; Mitchell, L. D.

    1986-01-01

    The effects of high frequency oscillations caused by the gear mesh, on components of a geared system that can be modeled as rigid discs are analyzed using linear dynamic coupling terms. The coupled, nonlinear equations of motion for a disc attached to a rotating shaft are presented. The results of a trial problem analysis show that the inclusion of the linear dynamic coupling terms can produce significant changes in the predicted response of geared rotor systems, and that the produced sideband responses are greater than the unbalanced response. The method is useful in designing gear drives for heavy-lift helicopters, industrial speed reducers, naval propulsion systems, and heavy off-road equipment.

  12. Dynamic modeling of the INAPRO aquaponic system

    NARCIS (Netherlands)

    Karimanzira, Divas; Keesman, Karel J.; Kloas, Werner; Baganz, Daniela; Rauschenbach, Thomas

    2016-01-01

    The use of modeling techniques to analyze aquaponics systems is demonstrated with an example of dynamic modeling for the production of Nile tilapia (Oreochromis niloticus) and tomatoes (Solanum lycopersicon) using the innovative double recirculating aquaponic system ASTAF-PRO. For the management

  13. Dynamic Systems Theory and Team Sport Coaching

    Science.gov (United States)

    Gréhaigne, Jean-Francis; Godbout, Paul

    2014-01-01

    This article examines the theory of dynamic systems and its use in the domains of the study and coaching of team sports. The two teams involved in a match are looked at as two interacting systems in movement, where opposition is paramount. A key element for the observation of game play is the notion of configuration of play and its ever-changing…

  14. Reaction dynamics in polyatomic molecular systems

    Energy Technology Data Exchange (ETDEWEB)

    Miller, W.H. [Lawrence Berkeley Laboratory, CA (United States)

    1993-12-01

    The goal of this program is the development of theoretical methods and models for describing the dynamics of chemical reactions, with specific interest for application to polyatomic molecular systems of special interest and relevance. There is interest in developing the most rigorous possible theoretical approaches and also in more approximate treatments that are more readily applicable to complex systems.

  15. Test computations on the dynamical evolution of star clusters. [Fluid dynamic method

    Energy Technology Data Exchange (ETDEWEB)

    Angeletti, L; Giannone, P. (Rome Univ. (Italy))

    1977-01-01

    Test calculations have been carried out on the evolution of star clusters using the fluid-dynamical method devised by Larson (1970). Large systems of stars have been considered with specific concern with globular clusters. With reference to the analogous 'standard' model by Larson, the influence of varying in turn the various free parameters (cluster mass, star mass, tidal radius, mass concentration of the initial model) has been studied for the results. Furthermore, the partial release of some simplifying assumptions with regard to the relaxation time and distribution of the 'target' stars has been considered. The change of the structural properties is discussed, and the variation of the evolutionary time scale is outlined. An indicative agreement of the results obtained here with structural properties of globular clusters as deduced from previous theoretical models is pointed out.

  16. Dynamic behavior and functional integrity tests on RC shear walls

    International Nuclear Information System (INIS)

    Akino, Kinji; Nasuda, Toshiaki; Shibata, Akenori.

    1991-01-01

    A project consisting of seven subprojects has been conducted to study the dynamic behavior and functional integrity of reinforced concrete (RC) shear walls in reactor buildings. The objective of this project is to obtain the data to improve and prepare the seismic analysis code regarding the nonlinear structural behavior and integrity of reactor buildings during and after earthquakes. The project started in April, 1986, and will end in March, 1994. Seven subprojects are strain rate test, damping characteristic test, ultimate state response test and the verification test for the test of restoring force characteristics regarding dynamic restoring force characteristics and damping performance; the restoring force characteristic test on the shear walls with openings; and pull-out strength test and the test on air leakage through concrete cracks regarding the functional integrity. The objectives of respective subprojects, the test models and the interim results are reported. Three subprojects have been completed by March, 1990. The results of these projects will be used for the overall evaluation. The strain rate test showed that the ultimate strength of shear walls increased with strain rate. A formula for estimating air flow through the cracks in walls was given by the leakage test. (K.I.)

  17. Dynamic model including piping acoustics of a centrifugal compression system

    NARCIS (Netherlands)

    Helvoirt, van J.; Jager, de A.G.

    2007-01-01

    This paper deals with low frequency pulsation phenomena in full-scale centrifugal compression systems associated with compressor surge. The Greitzer lumped parameter model is applied to describe the dynamic behavior of an industrial compressor test rig and experimental evidence is provided for the

  18. Innovative tools for real-time simulation of dynamic systems

    NARCIS (Netherlands)

    Palli, Gianluca; Carloni, Raffaella; Melchiorri, Claudio

    2008-01-01

    In this paper, we present a software architecture, based on RTAI-Linux, for the real-time simulation of dynamic systems and for the rapid prototyping of digital controllers. Our aim is to simplify the testing phase of digital controllers by providing the real-time simulation of the plant with the

  19. Dynamic MR imaging of the musculoskeletal system

    International Nuclear Information System (INIS)

    Shah, A.S.; Hylton, H.; Hentz, V.R.; Schattner, P.

    1991-01-01

    This paper reports on dynamic MR imaging which is an MR technique that allows imaging of the musculoskeletal system in motion. Current methods for observing the articulation of muscles and joints are limited to acquisition of stationary images at different spatial orientations. These images are then replayed from computer memory to simulate motion. Unlike stationary acquisition, dynamic MR imaging allows the volume of interest to be subjected to motion and dynamic stress, which is important for detecting stress-induced pathology. To demonstrate the utility of dynamic MR imaging, a system for imaging a moving wrist has been developed. The system consists of apparatus capable of providing simultaneous radialulnar deviation and flexion-extension, and hardware for system control and acquisition gating. The apparatus is mounted on the patient bed and is transferable to a variety of standard clinical MR imaging systems. Images were obtained during motion, and the ability of dynamic MR imaging to accurately image the moving wrist with very little motion artifact was demonstrated

  20. Solar dynamic power system definition study

    Science.gov (United States)

    Wallin, Wayne E.; Friefeld, Jerry M.

    1988-01-01

    The solar dynamic power system design and analysis study compared Brayton, alkali-metal Rankine, and free-piston Stirling cycles with silicon planar and GaAs concentrator photovoltaic power systems for application to missions beyond the Phase 2 Space Station level of technology for all power systems. Conceptual designs for Brayton and Stirling power systems were developed for 35 kWe and 7 kWe power levels. All power systems were designed for 7-year end-of-life conditions in low Earth orbit. LiF was selected for thermal energy storage for the solar dynamic systems. Results indicate that the Stirling cycle systems have the highest performance (lowest weight and area) followed by the Brayton cycle, with photovoltaic systems considerably lower in performance. For example, based on the performance assumptions used, the planar silicon power system weight was 55 to 75 percent higher than for the Stirling system. A technology program was developed to address areas wherein significant performance improvements could be realized relative to the current state-of-the-art as represented by Space Station. In addition, a preliminary evaluation of hardenability potential found that solar dynamic systems can be hardened beyond the hardness inherent in the conceptual designs of this study.

  1. Near Identifiability of Dynamical Systems

    Science.gov (United States)

    Hadaegh, F. Y.; Bekey, G. A.

    1987-01-01

    Concepts regarding approximate mathematical models treated rigorously. Paper presents new results in analysis of structural identifiability, equivalence, and near equivalence between mathematical models and physical processes they represent. Helps establish rigorous mathematical basis for concepts related to structural identifiability and equivalence revealing fundamental requirements, tacit assumptions, and sources of error. "Structural identifiability," as used by workers in this field, loosely translates as meaning ability to specify unique mathematical model and set of model parameters that accurately predict behavior of corresponding physical system.

  2. Dynamic Systems Modeling in Educational System Design & Policy

    Science.gov (United States)

    Groff, Jennifer Sterling

    2013-01-01

    Over the last several hundred years, local and national educational systems have evolved from relatively simple systems to incredibly complex, interdependent, policy-laden structures, to which many question their value, effectiveness, and direction they are headed. System Dynamics is a field of analysis used to guide policy and system design in…

  3. Transmitted wavefront testing with large dynamic range based on computer-aided deflectometry

    Science.gov (United States)

    Wang, Daodang; Xu, Ping; Gong, Zhidong; Xie, Zhongmin; Liang, Rongguang; Xu, Xinke; Kong, Ming; Zhao, Jun

    2018-06-01

    The transmitted wavefront testing technique is demanded for the performance evaluation of transmission optics and transparent glass, in which the achievable dynamic range is a key issue. A computer-aided deflectometric testing method with fringe projection is proposed for the accurate testing of transmitted wavefronts with a large dynamic range. Ray tracing of the modeled testing system is carried out to achieve the virtual ‘null’ testing of transmitted wavefront aberrations. The ray aberration is obtained from the ray tracing result and measured slope, with which the test wavefront aberration can be reconstructed. To eliminate testing system modeling errors, a system geometry calibration based on computer-aided reverse optimization is applied to realize accurate testing. Both numerical simulation and experiments have been carried out to demonstrate the feasibility and high accuracy of the proposed testing method. The proposed testing method can achieve a large dynamic range compared with the interferometric method, providing a simple, low-cost and accurate way for the testing of transmitted wavefronts from various kinds of optics and a large amount of industrial transmission elements.

  4. Contributions of Transonic Dynamics Tunnel Testing to Airplane Flutter Clearance

    Science.gov (United States)

    Rivera, Jose A.; Florance, James R.

    2000-01-01

    The Transonic Dynamics Tunnel (TDT) became in operational in 1960, and since that time has achieved the status of the world's premier wind tunnel for testing large in aeroelastically scaled models at transonic speeds. The facility has many features that contribute to its uniqueness for aeroelastic testing. This paper will briefly describe these capabilities and features, and their relevance to aeroelastic testing. Contributions to specific airplane configurations and highlights from the flutter tests performed in the TDT aimed at investigating the aeroelastic characteristics of these configurations are presented.

  5. Dynamics Explorer science data processing system

    International Nuclear Information System (INIS)

    Smith, P.H.; Freeman, C.H.; Hoffman, R.A.

    1981-01-01

    The Dynamics Explorer project has acquired the ground data processing system from the Atmosphere Explorer project to provide a central computer facility for the data processing, data management and data analysis activities of the investigators. Access to this system is via remote terminals at the investigators' facilities, which provide ready access to the data sets derived from groups of instruments on both spacecraft. The original system has been upgraded with both new hardware and enhanced software systems. These new systems include color and grey scale graphics terminals, an augmentation computer, micrographies facility, a versatile data base with a directory and data management system, and graphics display software packages. (orig.)

  6. Dynamic radioisotopic study of the salivary glands. Quantification test

    International Nuclear Information System (INIS)

    Estour, A.-B.

    1976-01-01

    Quantified dynamic radioisotopic exploration, a new and rational examination, should find its place in a thorough check-up of the salivary glands together with clinical, immunological, anatomopathological and sialographic investigations. The object of this work was to standardise the test procedure with a view to routine use on patients and to define certain quantified parameters representing objectively the different aspects of the salivary functions. Our procedure through reeding sophisticated equipment, is simple to perform and relies on use of: radiotechnetium employed at activities which allow repetitive exlorations whereby pathological changes may be followed; the gamma camera and its data processing system which records all radioactive information obtained on the patient's head. These results will supply the data needed to judge the salivary functions as a whole. The apparatus used provides a remarkable pictorial record made up not only of morphological and functional images at each stage of the examination but also of ciphered radioactivity versus time curves for each of the main salivary glands and for any other zone of interest. From these curves it is then possible to define quantified parameters, reproducible and expressing functional activity. This procedure, safe and painless, seems to suit the patients who lie still without complaint for 60 minutes, 45 minutes for the concentration study and 15 minutes for the post-stimulus excretion study. The dynamic radioisotopic examination of the salivary glands, by the comparison of concentration and excretion images and by the study of parameters, separately and as a whole, is thus a useful complement to other paraclinical examinations and contributes essential information in most salivary diseases [fr

  7. Dynamics of Nonlinear Time-Delay Systems

    CERN Document Server

    Lakshmanan, Muthusamy

    2010-01-01

    Synchronization of chaotic systems, a patently nonlinear phenomenon, has emerged as a highly active interdisciplinary research topic at the interface of physics, biology, applied mathematics and engineering sciences. In this connection, time-delay systems described by delay differential equations have developed as particularly suitable tools for modeling specific dynamical systems. Indeed, time-delay is ubiquitous in many physical systems, for example due to finite switching speeds of amplifiers in electronic circuits, finite lengths of vehicles in traffic flows, finite signal propagation times in biological networks and circuits, and quite generally whenever memory effects are relevant. This monograph presents the basics of chaotic time-delay systems and their synchronization with an emphasis on the effects of time-delay feedback which give rise to new collective dynamics. Special attention is devoted to scalar chaotic/hyperchaotic time-delay systems, and some higher order models, occurring in different bran...

  8. On non-stationarity of dynamic systems

    DEFF Research Database (Denmark)

    Høskuldsson, Agnar

    2004-01-01

    . Covariance structure of dynamic systems tends to vary over time. Here some procedures to find stable solutions to linear dynamic systems with low rank are presented. Subsets of variables and samples to be included in a model are considered. The procedures are based on the H-principle of mathematical...... that are based on exact solutions. With in few seconds the algorithms can provide with solutions of models having hundreds or thousands of variables. The procedure is described mathematically and demonstrated for a dynamic industrial case. It is shown how the algorithms can provide solutions involving NIR data...... for process control. The method is simple to apply and the motivation of the procedure is obvious for industrial applications. It can be used, e.g., when modelling on-line systems....

  9. Supervised Learning for Dynamical System Learning.

    Science.gov (United States)

    Hefny, Ahmed; Downey, Carlton; Gordon, Geoffrey J

    2015-01-01

    Recently there has been substantial interest in spectral methods for learning dynamical systems. These methods are popular since they often offer a good tradeoff between computational and statistical efficiency. Unfortunately, they can be difficult to use and extend in practice: e.g., they can make it difficult to incorporate prior information such as sparsity or structure. To address this problem, we present a new view of dynamical system learning: we show how to learn dynamical systems by solving a sequence of ordinary supervised learning problems, thereby allowing users to incorporate prior knowledge via standard techniques such as L 1 regularization. Many existing spectral methods are special cases of this new framework, using linear regression as the supervised learner. We demonstrate the effectiveness of our framework by showing examples where nonlinear regression or lasso let us learn better state representations than plain linear regression does; the correctness of these instances follows directly from our general analysis.

  10. Full scale dynamic testing of Kozloduy NPP unit 5 structures

    International Nuclear Information System (INIS)

    Da Rin, E.M.

    1999-01-01

    As described in this report, the Kozloduy NPP western site has been subjected to low level earthquake-like ground shaking - through appropriately devised underground explosions - and the resulting dynamic response of the NPP reactor Unit 5 important structures appropriately measured and digitally recorded. In-situ free-field response was measured concurrently more than 100 m aside the main structures of interest. The collected experimental data provide reference information on the actual dynamic characteristics of the Kozloduy NPPs main structures, as well as give some useful indications on the dynamic soil-structure interaction effects for the case of low level excitation. Performing the present full-scale dynamic structural testing activities took advantage of the experience gained by ISMES during similar tests, lately performed in Italy and abroad (in particular, at the Paks NPP in 1994). The IAEA promoted dynamic testing of the Kozloduy NPP Unit 5 by means of pertinently designed buried explosion-induced ground motions which has provided a large amount of data on the dynamic structural response of its major structures. In the present report, the conducted investigation is described and the acquired digital data presented. A series of preliminary analyses were undertaken for examining in detail the ground excitation levels that were produced by these weak earthquake simulation experiments, as well as for inferring some structural characteristics and behaviour information from the collected data. These analyses ascertained the high quality of the collected digital data. Presumably due to soil-structure dynamic interaction effects, reduced excitation levels were observed at the reactor building foundation raft level with respect to the concurrent free-field ground motions. measured at a 140 m distance from the reactor building centre. Further more detailed and systematic analyses are worthwhile to be performed for extracting more complete information about the

  11. Development of research reactor simulator and its application to dynamic test-bed

    International Nuclear Information System (INIS)

    Kwon, Kee-Choon; Baang, Dane; Park, Jae-Chang; Lee, Seung-Wook; Bae, Sung Won

    2014-01-01

    We developed a real-time simulator for 'High-flux Advanced Neutron Application ReactOr (HANARO), and the Jordan Research and Training Reactor (JRTR). The main purpose of this simulator is operator training, but we modified this simulator into a dynamic test-bed (DTB) to test the functions and dynamic control performance of reactor regulating system (RRS) in HANARO or JRTR before installation. The simulator hardware consists of a host computer, 6 operator stations, a network switch, and a large display panel. The software includes a mathematical model that implements plant dynamics in real-time, an instructor station module that manages user instructions, and a human machine interface module. The developed research reactor simulators are installed in the Korea Atomic Energy Research Institute nuclear training center for reactor operator training. To use the simulator as a dynamic test-bed, the reactor regulating system modeling software of the simulator was replaced by actual RRS cabinet, and was interfaced using a hard-wired and network-based interface. RRS cabinet generates control signals for reactor power control based on the various feedback signals from DTB, and the DTB runs plant dynamics based on the RRS control signals. Thus the Hardware-In-the-Loop Simulation between RRS and the emulated plant (DTB) has been implemented and tested in this configuration. The test result shows that the developed DTB and actual RRS cabinet works together simultaneously resulting in quite good dynamic control performances. (author)

  12. Dynamic tests for qualifying of national uranium hexafluoride

    International Nuclear Information System (INIS)

    Araujo Figueiredo, C. de; Abreu Mendonca Schvartzman, M.M. de; Vasconcelos, M.C.R.L.

    1990-01-01

    The dynamic behaviour of the Brazilian uranium hexafluoride is analyzed in this paper, with regard to its radiolytic decomposition and to the action of catalysts on the reaction between UF 6 and H 2 . The process gas (UF 6 /H 2 ) was submitted in the laboratory of dynamic tests (DV-II) to similar conditions as those used in the enrichment plant presently being erected in Resende - RJ, 'First Cascade - FC'. The tests carried out have shown that the Brazilian UF 6 has the same dynamic behaviour of the German UF 6 . It does not contain either any catalyst of the reaction between UF 6 and H 2 which could render it inappropriate for use in commercial plants. (author) [pt

  13. Uncertain dynamical systems: A differential game approach

    Science.gov (United States)

    Gutman, S.

    1976-01-01

    A class of dynamical systems in a conflict situation is formulated and discussed, and the formulation is applied to the study of an important class of systems in the presence of uncertainty. The uncertainty is deterministic and the only assumption is that its value belongs to a known compact set. Asymptotic stability is fully discussed with application to variable structure and model reference control systems.

  14. Nonlinear Dynamics, Chaotic and Complex Systems

    Science.gov (United States)

    Infeld, E.; Zelazny, R.; Galkowski, A.

    2011-04-01

    Part I. Dynamic Systems Bifurcation Theory and Chaos: 1. Chaos in random dynamical systems V. M. Gunldach; 2. Controlling chaos using embedded unstable periodic orbits: the problem of optimal periodic orbits B. R. Hunt and E. Ott; 3. Chaotic tracer dynamics in open hydrodynamical flows G. Karolyi, A. Pentek, T. Tel and Z. Toroczkai; 4. Homoclinic chaos L. P. Shilnikov; Part II. Spatially Extended Systems: 5. Hydrodynamics of relativistic probability flows I. Bialynicki-Birula; 6. Waves in ionic reaction-diffusion-migration systems P. Hasal, V. Nevoral, I. Schreiber, H. Sevcikova, D. Snita, and M. Marek; 7. Anomalous scaling in turbulence: a field theoretical approach V. Lvov and I. Procaccia; 8. Abelian sandpile cellular automata M. Markosova; 9. Transport in an incompletely chaotic magnetic field F. Spineanu; Part III. Dynamical Chaos Quantum Physics and Foundations Of Statistical Mechanics: 10. Non-equilibrium statistical mechanics and ergodic theory L. A. Bunimovich; 11. Pseudochaos in statistical physics B. Chirikov; 12. Foundations of non-equilibrium statistical mechanics J. P. Dougherty; 13. Thermomechanical particle simulations W. G. Hoover, H. A. Posch, C. H. Dellago, O. Kum, C. G. Hoover, A. J. De Groot and B. L. Holian; 14. Quantum dynamics on a Markov background and irreversibility B. Pavlov; 15. Time chaos and the laws of nature I. Prigogine and D. J. Driebe; 16. Evolutionary Q and cognitive systems: dynamic entropies and predictability of evolutionary processes W. Ebeling; 17. Spatiotemporal chaos information processing in neural networks H. Szu; 18. Phase transitions and learning in neural networks C. Van den Broeck; 19. Synthesis of chaos A. Vanecek and S. Celikovsky; 20. Computational complexity of continuous problems H. Wozniakowski; Part IV. Complex Systems As An Interface Between Natural Sciences and Environmental Social and Economic Sciences: 21. Stochastic differential geometry in finance studies V. G. Makhankov; Part V. Conference Banquet

  15. EXTRAP as a dynamic system

    International Nuclear Information System (INIS)

    Tendler, M.

    1986-04-01

    The behaviour of the plasma in the EXTRAP device was found to differ drastically from the conventional Z-pinch discharges. The comparative discussion on the properties of these two configurations is presented. It is shown that the energy mechanism is responsible for the arising difference between them. Given the lack of experimental data on the confinement of the peripheral plasma, in the present study we suggest a scaling for the net energy loss with plasma density and temperature. Using self-similar methods, we show that strongly non-linear damped oscillations arise as a result of our scaling. Some preliminary results on the stability of this system are reported. Finally, some technical recommendations for the design of the toroidal device EXTRAP T1 are put forward. In particular the scheme, allowing the extension of the pulse duration, which is rather limited in the present version, is suggested. (Author)

  16. Experimental benchmark for piping system dynamic response analyses

    International Nuclear Information System (INIS)

    Schott, G.A.; Mallett, R.H.

    1981-01-01

    The scope and status of a piping system dynamics test program are described. A 0.20-m nominal diameter test piping specimen is designed to be representative of main heat transport system piping of LMFBR plants. Attention is given to representing piping restraints. Applied loadings consider component-induced vibration as well as seismic excitation. The principal objective of the program is to provide a benchmark for verification of piping design methods by correlation of predicted and measured responses. Pre-test analysis results and correlation methods are discussed. 3 refs

  17. Experimental benchmark for piping system dynamic-response analyses

    International Nuclear Information System (INIS)

    1981-01-01

    This paper describes the scope and status of a piping system dynamics test program. A 0.20 m(8 in.) nominal diameter test piping specimen is designed to be representative of main heat transport system piping of LMFBR plants. Particular attention is given to representing piping restraints. Applied loadings consider component-induced vibration as well as seismic excitation. The principal objective of the program is to provide a benchmark for verification of piping design methods by correlation of predicted and measured responses. Pre-test analysis results and correlation methods are discussed

  18. Dynamic tension testing equipment for paperboard and corrugated fiberboard

    Science.gov (United States)

    W. D. Godshall

    1965-01-01

    The objective of this work was to develop a method, the testing equipment, and the instrumentation with which dynamic stress-strain information may be obtained for paperboards and built-up corrugated fiberboards as used in corrugated fiberboard containers. Much information is available on the properties of these materials when subjected to static or low rates of...

  19. Dynamic nuclear polarization tests in some polymers for polarized targets

    International Nuclear Information System (INIS)

    Brandt, B. van den; Hautle, P.; Konter, J.A.; Mango, S.; Bunyatova, E.I.

    1998-01-01

    The results of dynamic polarization tests in polyethylene (PE) and ethylene propylene copolymer (EPC), doped with the stable free radical 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO), are presented. Sizable proton polarizations have been achieved in a magnetic field of 2.5 T at a temperature below 0.3 K and 5T at 1 K

  20. Test results of HTTR control system

    International Nuclear Information System (INIS)

    Motegi, Toshihiro; Iigaki, Kazuhiko; Saito, Kenji; Sawahata, Hiroaki; Hirato, Yoji; Kondo, Makoto; Shibutani, Hideki; Ogawa, Satoru; Shinozaki, Masayuki; Mizushima, Toshihiko; Kawasaki, Kozo

    2006-06-01

    The plant control performance of the IHX helium flow rate control system, the PPWC helium flow rate control system, the secondary helium flow rate control system, the inlet temperature control system, the reactor power control system and the outlet temperature control system of the HTTR are obtained through function tests and power-up tests. As the test results, the control systems show stable control response under transient condition. Both of inlet temperature control system and reactor power control system shows stable operation from 30% to 100%, respectively. This report describes the outline of control systems and test results. (author)

  1. System Dynamics Modeling of Multipurpose Reservoir Operation

    Directory of Open Access Journals (Sweden)

    Ebrahim Momeni

    2006-03-01

    Full Text Available System dynamics, a feedback – based object – oriented simulation approach, not only represents complex dynamic systemic systems in a realistic way but also allows the involvement of end users in model development to increase their confidence in modeling process. The increased speed of model development, the possibility of group model development, the effective communication of model results, and the trust developed in the model due to user participation are the main strengths of this approach. The ease of model modification in response to changes in the system and the ability to perform sensitivity analysis make this approach more attractive compared with systems analysis techniques for modeling water management systems. In this study, a system dynamics model was developed for the Zayandehrud basin in central Iran. This model contains river basin, dam reservoir, plains, irrigation systems, and groundwater. Current operation rule is conjunctive use of ground and surface water. Allocation factor for each irrigation system is computed based on the feedback from groundwater storage in its zone. Deficit water is extracted from groundwater.The results show that applying better rules can not only satisfy all demands such as Gawkhuni swamp environmental demand, but it can also  prevent groundwater level drawdown in future.

  2. System Testing of Desktop and Web Applications

    Science.gov (United States)

    Slack, James M.

    2011-01-01

    We want our students to experience system testing of both desktop and web applications, but the cost of professional system-testing tools is far too high. We evaluate several free tools and find that AutoIt makes an ideal educational system-testing tool. We show several examples of desktop and web testing with AutoIt, starting with simple…

  3. Robust control synthesis for uncertain dynamical systems

    Science.gov (United States)

    Byun, Kuk-Whan; Wie, Bong; Sunkel, John

    1989-01-01

    This paper presents robust control synthesis techniques for uncertain dynamical systems subject to structured parameter perturbation. Both QFT (quantitative feedback theory) and H-infinity control synthesis techniques are investigated. Although most H-infinity-related control techniques are not concerned with the structured parameter perturbation, a new way of incorporating the parameter uncertainty in the robust H-infinity control design is presented. A generic model of uncertain dynamical systems is used to illustrate the design methodologies investigated in this paper. It is shown that, for a certain noncolocated structural control problem, use of both techniques results in nonminimum phase compensation.

  4. Topological equivalence of nonlinear autonomous dynamical systems

    International Nuclear Information System (INIS)

    Nguyen Huynh Phan; Tran Van Nhung

    1995-12-01

    We show in this paper that the autonomous nonlinear dynamical system Σ(A,B,F): x' = Ax+Bu+F(x) is topologically equivalent to the linear dynamical system Σ(A,B,O): x' = Ax+Bu if the projection of A on the complement in R n of the controllable vectorial subspace is hyperbolic and if lipschitz constant of F is sufficiently small ( * ) and F(x) = 0 when parallel x parallel is sufficiently large ( ** ). In particular, if Σ(A,B,O) is controllable, it is topologically equivalent to Σ(A,B,F) when it is only that F satisfy ( ** ). (author). 18 refs

  5. Dynamic Control Based Photovoltaic Illuminating System

    Directory of Open Access Journals (Sweden)

    Zhang Chengkai

    2016-01-01

    Full Text Available Smart LED illumination system can use the power from whether the photovoltaic cell or the power grid automatically based on the SOC (State Of Charge of the photovoltaic cell. This paper proposes a feedback control of the photovoltaic cells and a dynamic control strategy for the Energy system. The dynamic control strategy is used to determine the switching state of the photovoltaic cell based on the illumination load in the past one hour and the battery capacity. These controls are manifested by experimental prototype that the control scheme is correct and effective.

  6. High dynamic range coding imaging system

    Science.gov (United States)

    Wu, Renfan; Huang, Yifan; Hou, Guangqi

    2014-10-01

    We present a high dynamic range (HDR) imaging system design scheme based on coded aperture technique. This scheme can help us obtain HDR images which have extended depth of field. We adopt Sparse coding algorithm to design coded patterns. Then we utilize the sensor unit to acquire coded images under different exposure settings. With the guide of the multiple exposure parameters, a series of low dynamic range (LDR) coded images are reconstructed. We use some existing algorithms to fuse and display a HDR image by those LDR images. We build an optical simulation model and get some simulation images to verify the novel system.

  7. Testing of a Microanalysis System

    NARCIS (Netherlands)

    Kerkhoff, Hans G.

    2001-01-01

    During the testing of microsystems, one has to cope with many problems resulting from inaccessibility, different technologies, and nonelectrical failure modes. A number of mixed-signal test techniques have been applied to test a new advanced microsystem. The choices on testing are directly dependent

  8. Trust dynamics in a large system implementation

    DEFF Research Database (Denmark)

    Schlichter, Bjarne Rerup; Rose, Jeremy

    2013-01-01

    outcomes, but largely ignored the dynamics of trust relations. Giddens, as part of his study of modernity, theorises trust dynamics in relation to abstract social systems, though without focusing on information systems. We use Giddens’ concepts to investigate evolving trust relationships in a longitudinal......A large information systems implementation (such as Enterprise Resource Planning systems) relies on the trust of its stakeholders to succeed. Such projects impact diverse groups of stakeholders, each with their legitimate interests and expectations. Levels of stakeholder trust can be expected...... case analysis of a large Integrated Hospital System implementation for the Faroe Islands. Trust relationships suffered a serious breakdown, but the project was able to recover and meet its goals. We develop six theoretical propositions theorising the relationship between trust and project outcomes...

  9. Constraint Embedding Technique for Multibody System Dynamics

    Science.gov (United States)

    Woo, Simon S.; Cheng, Michael K.

    2011-01-01

    Multibody dynamics play a critical role in simulation testbeds for space missions. There has been a considerable interest in the development of efficient computational algorithms for solving the dynamics of multibody systems. Mass matrix factorization and inversion techniques and the O(N) class of forward dynamics algorithms developed using a spatial operator algebra stand out as important breakthrough on this front. Techniques such as these provide the efficient algorithms and methods for the application and implementation of such multibody dynamics models. However, these methods are limited only to tree-topology multibody systems. Closed-chain topology systems require different techniques that are not as efficient or as broad as those for tree-topology systems. The closed-chain forward dynamics approach consists of treating the closed-chain topology as a tree-topology system subject to additional closure constraints. The resulting forward dynamics solution consists of: (a) ignoring the closure constraints and using the O(N) algorithm to solve for the free unconstrained accelerations for the system; (b) using the tree-topology solution to compute a correction force to enforce the closure constraints; and (c) correcting the unconstrained accelerations with correction accelerations resulting from the correction forces. This constraint-embedding technique shows how to use direct embedding to eliminate local closure-loops in the system and effectively convert the system back to a tree-topology system. At this point, standard tree-topology techniques can be brought to bear on the problem. The approach uses a spatial operator algebra approach to formulating the equations of motion. The operators are block-partitioned around the local body subgroups to convert them into aggregate bodies. Mass matrix operator factorization and inversion techniques are applied to the reformulated tree-topology system. Thus in essence, the new technique allows conversion of a system with

  10. Do dynamical systems follow Benford's law?

    International Nuclear Information System (INIS)

    Tolle, Charles R.; Budzien, Joanne L.; LaViolette, Randall A.

    2000-01-01

    Data compiled from a variety of sources follow Benford's law, which gives a monotonically decreasing distribution of the first digit (1 through 9). We examine the frequency of the first digit of the coordinates of the trajectories generated by some common dynamical systems. One-dimensional cellular automata fulfill the expectation that the frequency of the first digit is uniform. The molecular dynamics of fluids, on the other hand, provides trajectories that follow Benford's law. Finally, three chaotic systems are considered: Lorenz, Henon, and Roessler. The Lorenz system generates trajectories that follow Benford's law. The Henon system generates trajectories that resemble neither the uniform distribution nor Benford's law. Finally, the Roessler system generates trajectories that follow the uniform distribution for some parameters choices, and Benford's law for others. (c) 2000 American Institute of Physics

  11. Complex and adaptive dynamical systems a primer

    CERN Document Server

    Gros, Claudius

    2007-01-01

    We are living in an ever more complex world, an epoch where human actions can accordingly acquire far-reaching potentialities. Complex and adaptive dynamical systems are ubiquitous in the world surrounding us and require us to adapt to new realities and the way of dealing with them. This primer has been developed with the aim of conveying a wide range of "commons-sense" knowledge in the field of quantitative complex system science at an introductory level, providing an entry point to this both fascinating and vitally important subject. The approach is modular and phenomenology driven. Examples of emerging phenomena of generic importance treated in this book are: -- The small world phenomenon in social and scale-free networks. -- Phase transitions and self-organized criticality in adaptive systems. -- Life at the edge of chaos and coevolutionary avalanches resulting from the unfolding of all living. -- The concept of living dynamical systems and emotional diffusive control within cognitive system theory. Techn...

  12. Complex and Adaptive Dynamical Systems A Primer

    CERN Document Server

    Gros, Claudius

    2011-01-01

    We are living in an ever more complex world, an epoch where human actions can accordingly acquire far-reaching potentialities. Complex and adaptive dynamical systems are ubiquitous in the world surrounding us and require us to adapt to new realities and the way of dealing with them. This primer has been developed with the aim of conveying a wide range of "commons-sense" knowledge in the field of quantitative complex system science at an introductory level, providing an entry point to this both fascinating and vitally important subject. The approach is modular and phenomenology driven. Examples of emerging phenomena of generic importance treated in this book are: -- The small world phenomenon in social and scale-free networks. -- Phase transitions and self-organized criticality in adaptive systems. -- Life at the edge of chaos and coevolutionary avalanches resulting from the unfolding of all living. -- The concept of living dynamical systems and emotional diffusive control within cognitive system theory. Techn...

  13. Testing of nuclear air-cleaning systems

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    A standard is presented which describes methods for field-testing nuclear power plant air cleaning systems. Included are specifications for visual inspection; duct and housing leak test; mounting frame pressure leak test; airflow capacity, distribution, and residence time tests; air-aerosol mixing uniformity test; in place leak test of HEPA filter banks; multiple sampling technique; in-place leak test of adsorber stage; laboratory testing of adsorbent; and duct heater performance test

  14. Fatigue tests of dowel-socket systems

    International Nuclear Information System (INIS)

    Chiang, D.D.

    1976-01-01

    A test program was conducted to determine the fatigue behavior of LHTGR fuel element dowel/socket systems. Two dowel/socket systems, namely, a four-dowel system and a five-dowel system, were tested to failure under shear loads applied through a fatigue test apparatus to simulate repetitive loading during a seismic event

  15. Cardea: Dynamic Access Control in Distributed Systems

    Science.gov (United States)

    Lepro, Rebekah

    2004-01-01

    Modern authorization systems span domains of administration, rely on many different authentication sources, and manage complex attributes as part of the authorization process. This . paper presents Cardea, a distributed system that facilitates dynamic access control, as a valuable piece of an inter-operable authorization framework. First, the authorization model employed in Cardea and its functionality goals are examined. Next, critical features of the system architecture and its handling of the authorization process are then examined. Then the S A M L and XACML standards, as incorporated into the system, are analyzed. Finally, the future directions of this project are outlined and connection points with general components of an authorization system are highlighted.

  16. Solar dynamic power systems for space station

    Science.gov (United States)

    Irvine, Thomas B.; Nall, Marsha M.; Seidel, Robert C.

    1986-01-01

    The Parabolic Offset Linearly Actuated Reflector (POLAR) solar dynamic module was selected as the baseline design for a solar dynamic power system aboard the space station. The POLAR concept was chosen over other candidate designs after extensive trade studies. The primary advantages of the POLAR concept are the low mass moment of inertia of the module about the transverse boom and the compactness of the stowed module which enables packaging of two complete modules in the Shuttle orbiter payload bay. The fine pointing control system required for the solar dynamic module has been studied and initial results indicate that if disturbances from the station are allowed to back drive the rotary alpha joint, pointing errors caused by transient loads on the space station can be minimized. This would allow pointing controls to operate in bandwidths near system structural frequencies. The incorporation of the fine pointing control system into the solar dynamic module is fairly straightforward for the three strut concentrator support structure. However, results of structural analyses indicate that this three strut support is not optimum. Incorporation of a vernier pointing system into the proposed six strut support structure is being studied.

  17. Full scale dynamic testing of Paks nuclear power plant structures

    International Nuclear Information System (INIS)

    Da Rin, E.M.

    1995-01-01

    This report refers to the full-scale dynamic structural testing activities that have been performed in December 1994 at the Paks (H) Nuclear Power Plant, within the framework of: the IAEA Coordinated research Programme 'Benchmark Study for the Seismic Analysis and Testing of WWER-type Nuclear Power Plants, and the nuclear research activities of ENEL-WR/YDN, the Italian National Electricity Board in Rome. The specific objective of the conducted investigation was to obtain valid data on the dynamic behaviour of the plant's major constructions, under normal operating conditions, for enabling an assessment of their actual seismic safety to be made. As described in more detail hereafter, the Paks NPP site has been subjected to low level earthquake like ground shaking, through appropriately devised underground explosions, and the dynamic response of the plant's 1 st reactor unit important structures was appropriately measured and digitally recorded. In-situ free field response was measured concurrently and, moreover, site-specific geophysical and seismological data were simultaneously acquired too. The above-said experimental data is to provide basic information on the geophysical and seismological characteristics of the Paks NPP site, together with useful reference information on the true dynamic characteristics of its main structures and give some indications on the actual dynamic soil-structure interaction effects for the case of low level excitation

  18. Dynamic Extensions of Batch Systems with Cloud Resources

    International Nuclear Information System (INIS)

    Hauth, T; Quast, G; Büge, V; Scheurer, A; Kunze, M; Baun, C

    2011-01-01

    Compute clusters use Portable Batch Systems (PBS) to distribute workload among individual cluster machines. To extend standard batch systems to Cloud infrastructures, a new service monitors the number of queued jobs and keeps track of the price of available resources. This meta-scheduler dynamically adapts the number of Cloud worker nodes according to the requirement profile. Two different worker node topologies are presented and tested on the Amazon EC2 Cloud service.

  19. Experimental test of static and dynamic characteristics of tilting-pad thrust bearings

    OpenAIRE

    Annan Guo; Xiaojing Wang; Jian Jin; Diann Y Hua; Zikai Hua

    2015-01-01

    The axial vibration in turbine machine has attracted more and more interest. Tilting-pad thrust bearings are widely used in turbine machines to support the axial load. The dynamic properties generated by oil film of the thrust pad have important effects on the axial vibration of the rotor-bearing system. It is necessary to develop the method to test the dynamic characteristics of thrust bearings. A new rig has been developed. The facility allows a complete set of bearing operating parameters ...

  20. An exploration of dynamical systems and chaos

    CERN Document Server

    Argyris, John H; Haase, Maria; Friedrich, Rudolf

    2015-01-01

    This book is conceived as a comprehensive and detailed text-book on non-linear dynamical systems with particular emphasis on the exploration of chaotic phenomena. The self-contained introductory presentation is addressed both to those who wish to study the physics of chaotic systems and non-linear dynamics intensively as well as those who are curious to learn more about the fascinating world of chaotic phenomena. Basic concepts like Poincaré section, iterated mappings, Hamiltonian chaos and KAM theory, strange attractors, fractal dimensions, Lyapunov exponents, bifurcation theory, self-similarity and renormalisation and transitions to chaos are thoroughly explained. To facilitate comprehension, mathematical concepts and tools are introduced in short sub-sections. The text is supported by numerous computer experiments and a multitude of graphical illustrations and colour plates emphasising the geometrical and topological characteristics of the underlying dynamics. This volume is a completely revised and enlar...

  1. Brand Equity Evolution: a System Dynamics Model

    Directory of Open Access Journals (Sweden)

    Edson Crescitelli

    2009-04-01

    Full Text Available One of the greatest challenges in brand management lies in monitoring brand equity over time. This paper aimsto present a simulation model able to represent this evolution. The model was drawn on brand equity concepts developed by Aaker and Joachimsthaler (2000, using the system dynamics methodology. The use ofcomputational dynamic models aims to create new sources of information able to sensitize academics and managers alike to the dynamic implications of their brand management. As a result, an easily implementable model was generated, capable of executing continuous scenario simulations by surveying casual relations among the variables that explain brand equity. Moreover, the existence of a number of system modeling tools will allow extensive application of the concepts used in this study in practical situations, both in professional and educational settings

  2. Integrability of dynamical systems algebra and analysis

    CERN Document Server

    Zhang, Xiang

    2017-01-01

    This is the first book to systematically state the fundamental theory of integrability and its development of ordinary differential equations with emphasis on the Darboux theory of integrability and local integrability together with their applications. It summarizes the classical results of Darboux integrability and its modern development together with their related Darboux polynomials and their applications in the reduction of Liouville and elementary integrabilty and in the center—focus problem, the weakened Hilbert 16th problem on algebraic limit cycles and the global dynamical analysis of some realistic models in fields such as physics, mechanics and biology. Although it can be used as a textbook for graduate students in dynamical systems, it is intended as supplementary reading for graduate students from mathematics, physics, mechanics and engineering in courses related to the qualitative theory, bifurcation theory and the theory of integrability of dynamical systems.

  3. Energy Systems Test Area (ESTA) Electrical Power Systems Test Operations: User Test Planning Guide

    Science.gov (United States)

    Salinas, Michael J.

    2012-01-01

    Test process, milestones and inputs are unknowns to first-time users of the ESTA Electrical Power Systems Test Laboratory. The User Test Planning Guide aids in establishing expectations for both NASA and non-NASA facility customers. The potential audience for this guide includes both internal and commercial spaceflight hardware/software developers. It is intended to assist their test engineering personnel in test planning and execution. Material covered includes a roadmap of the test process, roles and responsibilities of facility and user, major milestones, facility capabilities, and inputs required by the facility. Samples of deliverables, test article interfaces, and inputs necessary to define test scope, cost, and schedule are included as an appendix to the guide.

  4. Accelerated Testing of Polymeric Composites Using the Dynamic Mechanical Analyzer

    Science.gov (United States)

    Abdel-Magid, Becky M.; Gates, Thomas S.

    2000-01-01

    Creep properties of IM7/K3B composite material were obtained using three accelerated test methods at elevated temperatures. Results of flexural creep tests using the dynamic mechanical analyzer (DMA) were compared with results of conventional tensile and compression creep tests. The procedures of the three test methods are described and the results are presented. Despite minor differences in the time shift factor of the creep compliance curves, the DMA results compared favorably with the results from the tensile and compressive creep tests. Some insight is given into establishing correlations between creep compliance in flexure and creep compliance in tension and compression. It is shown that with careful consideration of the limitations of flexure creep, a viable and reliable accelerated test procedure can be developed using the DMA to obtain the viscoelastic properties of composites in extreme environments.

  5. Implementation and Test of the Automatic Flight Dynamics Operations for Geostationary Satellite Mission

    Directory of Open Access Journals (Sweden)

    Sangwook Park

    2009-12-01

    Full Text Available This paper describes the Flight Dynamics Automation (FDA system for COMS Flight Dynamics System (FDS and its test result in terms of the performance of the automation jobs. FDA controls the flight dynamics functions such as orbit determination, orbit prediction, event prediction, and fuel accounting. The designed FDA is independent from the specific characteristics which are defined by spacecraft manufacturer or specific satellite missions. Therefore, FDA could easily links its autonomous job control functions to any satellite mission control system with some interface modification. By adding autonomous system along with flight dynamics system, it decreases the operator’s tedious and repeated jobs but increase the usability and reliability of the system. Therefore, FDA is used to improve the completeness of whole mission control system’s quality. The FDA is applied to the real flight dynamics system of a geostationary satellite, COMS and the experimental test is performed. The experimental result shows the stability and reliability of the mission control operations through the automatic job control.

  6. Dynamics of railway bridges, analysis and verification by field tests

    Directory of Open Access Journals (Sweden)

    Andersson Andreas

    2015-01-01

    Full Text Available The following paper discusses different aspects of railway bridge dynamics, comprising analysis, modelling procedures and experimental testing. The importance of realistic models is discussed, especially regarding boundary conditions, load distribution and soil-structure interaction. Two theoretical case studies are presented, involving both deterministic and probabilistic assessment of a large number of railway bridges using simplified and computationally efficient models. A total of four experimental case studies are also introduced, illustrating different aspects and phenomena in bridge dynamics. The excitation consists of both ambient vibrations, train induced vibrations, free vibrations after train passages and controlled forced excitation.

  7. Modeling dynamic acousto-elastic testing experiments: validation and perspectives.

    Science.gov (United States)

    Gliozzi, A S; Scalerandi, M

    2014-10-01

    Materials possessing micro-inhomogeneities often display a nonlinear response to mechanical solicitations, which is sensitive to the confining pressure acting on the sample. Dynamic acoustoelastic testing allows measurement of the instantaneous variations in the elastic modulus due to the change of the dynamic pressure induced by a low-frequency wave. This paper shows that a Preisach-Mayergoyz space based hysteretic multi-state elastic model provides an explanation for experimental observations in consolidated granular media and predicts memory and nonlinear effects comparable to those measured in rocks.

  8. Static and Dynamic Handgrip Strength Endurance: Test-Retest Reproducibility.

    Science.gov (United States)

    Gerodimos, Vassilis; Karatrantou, Konstantina; Psychou, Dimitra; Vasilopoulou, Theodora; Zafeiridis, Andreas

    2017-03-01

    This study investigated the reliability of static and dynamic handgrip strength endurance using different protocols and indicators for the assessment of strength endurance. Forty young, healthy men and women (age, 18-22 years) performed 2 handgrip strength endurance protocols: a static protocol (sustained submaximal contraction at 50% of maximal voluntary contraction) and a dynamic one (8, 10, and 12 maximal repetitions). The participants executed each protocol twice to assess the test-retest reproducibility. Total work and total time were used as indicators of strength endurance in the static protocol; the strength recorded at each maximal repetition, the percentage change, and fatigue index were used as indicators of strength endurance in the dynamic protocol. The static protocol showed high reliability irrespective of sex and hand for total time and work. The 12-repetition dynamic protocol exhibited moderate-high reliability for repeated maximal repetitions and percentage change; the 8- and 10-repetition protocols demonstrated lower reliability irrespective of sex and hand. The fatigue index was not a reliable indicator for the assessment of dynamic handgrip endurance. Static handgrip endurance can be measured reliably using the total time and total work as indicators of strength endurance. For the evaluation of dynamic handgrip endurance, the 12-repetition protocol is recommended, using the repeated maximal repetitions and percentage change as indicators of strength endurance. Practitioners should consider the static (50% maximal voluntary contraction) and dynamic (12 repeated maximal repetitions) protocols as reliable for the assessment of handgrip strength endurance. The evaluation of static endurance in conjunction with dynamic endurance would provide more complete information about hand function. Copyright © 2017 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  9. State dynamics of a double sandbar system

    NARCIS (Netherlands)

    Price, T.D.; Ruessink, B.G.

    2011-01-01

    A 9.3-year dataset of low-tide time-exposure images from Surfers Paradise, Northern Gold Coast, Australia was used to characterise the state dynamics of a double sandbar system. The morphology of the nearshore sandbars was described by means of the sequential bar state classification scheme of

  10. Geometric analysis of nondeterminacy in dynamical systems

    DEFF Research Database (Denmark)

    Wisniewski, Rafal; Raussen, Martin Hubert

    2007-01-01

    This article intends to provide some new insights into concurrency using ideas from the theory of dynamical systems. Inherently discrete concurrency corresponds to a parallel continuous concept: a discrete state space corresponds to a differential manifold, an execution path corresponds to a flow...

  11. Invariant of dynamical systems: A generalized entropy

    International Nuclear Information System (INIS)

    Meson, A.M.; Vericat, F.

    1996-01-01

    In this work the concept of entropy of a dynamical system, as given by Kolmogorov, is generalized in the sense of Tsallis. It is shown that this entropy is an isomorphism invariant, being complete for Bernoulli schemes. copyright 1996 American Institute of Physics

  12. Dynamical Systems Approaches to Emotional Development

    Science.gov (United States)

    Camras, Linda A.; Witherington, David C.

    2005-01-01

    Within the last 20 years, transitions in the conceptualization of emotion and its development have given rise to calls for an explanatory framework that captures emotional development in all its organizational complexity and variability. Recent attempts have been made to couch emotional development in terms of a dynamical systems approach through…

  13. Organizing Performance Requirements For Dynamical Systems

    Science.gov (United States)

    Malchow, Harvey L.; Croopnick, Steven R.

    1990-01-01

    Paper describes methodology for establishing performance requirements for complicated dynamical systems. Uses top-down approach. In series of steps, makes connections between high-level mission requirements and lower-level functional performance requirements. Provides systematic delineation of elements accommodating design compromises.

  14. Improving homogeneity by dynamic speed limit systems.

    NARCIS (Netherlands)

    Nes, N. van Brandenberg, S. & Twisk, D.A.M.

    2010-01-01

    Homogeneity of driving speeds is an important variable in determining road safety; more homogeneous driving speeds increase road safety. This study investigates the effect of introducing dynamic speed limit systems on homogeneity of driving speeds. A total of 46 subjects twice drove a route along 12

  15. The Self as a Complex Dynamic System

    Science.gov (United States)

    Mercer, Sarah

    2011-01-01

    This article explores the potential offered by complexity theories for understanding language learners' sense of self and attempts to show how the self might usefully be conceived of as a complex dynamic system. Rather than presenting empirical findings, the article discusses existent research on the self and aims at outlining a conceptual…

  16. The dynamics of antilock brake systems

    Science.gov (United States)

    Denny, Mark

    2005-11-01

    The nonlinear dynamics of automobile braking are investigated. Nonlinearity arises because of the manner in which the friction coefficient between vehicle tyres and road surface depends upon vehicle speed and wheel angular speed. We show how antilock brake systems approach optimum braking performance.

  17. Book Review: Dynamic Systems for Everyone

    Science.gov (United States)

    Asish Ghosh starts the epilogue of the second edition of Dynamic Systems for Everyone with this quote: “We are now witnessing major technological advancements in areas, like artificial intelligence, robotics and self driven cars. …The pace of change is accelerating, ...

  18. On multi-dissipative dynamic systems

    DEFF Research Database (Denmark)

    Thygesen, Uffe Høgsbro

    1999-01-01

    We consider deterministic dynamic systems with state space representations which are dissipative in the sense of Willems (1972) with respect to several supply rates. This property is of interest in robustness analysis and in multi-objective control. We give conditions under which the convex cone...

  19. Induced topological pressure for topological dynamical systems

    International Nuclear Information System (INIS)

    Xing, Zhitao; Chen, Ercai

    2015-01-01

    In this paper, inspired by the article [J. Jaerisch et al., Stochastics Dyn. 14, 1350016, pp. 1-30 (2014)], we introduce the induced topological pressure for a topological dynamical system. In particular, we prove a variational principle for the induced topological pressure

  20. Stochastic properties of the Friedman dynamical system

    International Nuclear Information System (INIS)

    Szydlowski, M.; Heller, M.; Golda, Z.

    1985-01-01

    Some mathematical aspects of the stochastic cosmology are discussed in the corresponding ordinary Friedman world models. In particulare, it is shown that if the strong and Lorentz energy conditions are known, or the potential function is given, or a stochastic measure is suitably defined then the structure of the phase plane of the Friedman dynamical system is determined. 11 refs., 2 figs. (author)

  1. Abstraction of Dynamical Systems by Timed Automata

    DEFF Research Database (Denmark)

    Wisniewski, Rafael; Sloth, Christoffer

    2011-01-01

    To enable formal verification of a dynamical system, given by a set of differential equations, it is abstracted by a finite state model. This allows for application of methods for model checking. Consequently, it opens the possibility of carrying out the verification of reachability and timing re...

  2. The dynamics of surge in compression systems

    Indian Academy of Sciences (India)

    is of interest to study compression-system surge to understand its dynamics in order ... Internal problems like compressor going into rotating stall, resulting in loss of ... of water column, was used for mass-flow measurement at the impeller entry.

  3. LOCAL ENTROPY FUNCTION OF DYNAMICAL SYSTEM

    Directory of Open Access Journals (Sweden)

    İsmail TOK

    2013-05-01

    Full Text Available In this work, we first,define the entropy function of the topological dynamical system and investigate basic properties of this function without going into details. Let (X,A,T be a probability measure space and consider P = { pl5p2,...,pn} a finite measurable partition of all sub-sets of topological dynamical system (X,T.Then,the quantity H (P = ^ zpt is called the i=1 entropy function of finite measurable partition P.Where f-1 log t if 0 0.If diam(P < s,then the quantity L^ (T = h^ (T - h^ (T,P is called a local entropy function of topological dynamical system (X,T . In conclusion, Let (X,T and (Y,S be two topological dynamical system. If TxS is a transformation defined on the product space (XxY,TxS with (TxS(x , y = (Tx,Sy for all (x,y X x Y.Then L ^^ (TxS = L^d(T + L (S .and, we prove some fundamental properties of this function.

  4. Solar-System Tests of Gravitational Theories

    Science.gov (United States)

    Shapiro, Irwin

    1997-01-01

    We are engaged in testing gravitational theory by means of observations of objects in the solar system. These tests include an examination of the Principle Of Equivalence (POE), the Shapiro delay, the advances of planetary perihelia, the possibility of a secular variation G in the "gravitational constant" G, and the rate of the de Sitter (geodetic) precession of the Earth-Moon system. These results are consistent with our preliminary results focusing on the contribution of Lunar Laser Ranging (LLR), which were presented at the seventh Marcel Grossmann meeting on general relativity. The largest improvement over previous results comes in the uncertainty for (eta): a factor of five better than our previous value. This improvement reflects the increasing strength of the LLR data. A similar analysis presented at the same meeting by a group at the Jet Propulsion Laboratory gave a similar result for (eta). Our value for (beta) represents our first such result determined simultaneously with the solar quadrupole moment from the dynamical data set. These results are being prepared for publication. We have shown how positions determined from different planetary ephemerides can be compared and how the combination of VLBI and pulse timing information can yield a direct tie between planetary and radio frames. We have continued to include new data in our analysis as they became available. Finally, we have made improvement in our analysis software (PEP) and ported it to a network of modern workstations from its former home on a "mainframe" computer.

  5. Design tools for complex dynamic security systems.

    Energy Technology Data Exchange (ETDEWEB)

    Byrne, Raymond Harry; Rigdon, James Brian; Rohrer, Brandon Robinson; Laguna, Glenn A.; Robinett, Rush D. III (.; ); Groom, Kenneth Neal; Wilson, David Gerald; Bickerstaff, Robert J.; Harrington, John J.

    2007-01-01

    The development of tools for complex dynamic security systems is not a straight forward engineering task but, rather, a scientific task where discovery of new scientific principles and math is necessary. For years, scientists have observed complex behavior but have had difficulty understanding it. Prominent examples include: insect colony organization, the stock market, molecular interactions, fractals, and emergent behavior. Engineering such systems will be an even greater challenge. This report explores four tools for engineered complex dynamic security systems: Partially Observable Markov Decision Process, Percolation Theory, Graph Theory, and Exergy/Entropy Theory. Additionally, enabling hardware technology for next generation security systems are described: a 100 node wireless sensor network, unmanned ground vehicle and unmanned aerial vehicle.

  6. Dynamics of quasi-stable dissipative systems

    CERN Document Server

    Chueshov, Igor

    2015-01-01

    This book is  devoted to background material and recently developed mathematical methods in the study of infinite-dimensional dissipative systems. The theory of such systems is motivated by the long-term goal to establish rigorous mathematical models for turbulent and chaotic phenomena. The aim here is to offer general methods and abstract results pertaining to fundamental dynamical systems properties related to dissipative long-time behavior. The book systematically presents, develops and uses the quasi-stability method while substantially extending it by including for consideration new classes of models and PDE systems arising in Continuum Mechanics. The book can be used as a textbook in dissipative dynamics at the graduate level.   Igor Chueshov is a Professor of Mathematics at Karazin Kharkov National University in Kharkov, Ukraine.

  7. Quantum speed limits in open system dynamics

    OpenAIRE

    del Campo, A.; Egusquiza, I. L.; Plenio, M. B.; Huelga, S. F.

    2012-01-01

    Bounds to the speed of evolution of a quantum system are of fundamental interest in quantum metrology, quantum chemical dynamics and quantum computation. We derive a time-energy uncertainty relation for open quantum systems undergoing a general, completely positive and trace preserving (CPT) evolution which provides a bound to the quantum speed limit. When the evolution is of the Lindblad form, the bound is analogous to the Mandelstam-Tamm relation which applies in the unitary case, with the ...

  8. Coherence and chaos in extended dynamical systems

    International Nuclear Information System (INIS)

    Bishop, A.R.

    1994-01-01

    Coherence, chaos, and pattern formation are characteristic elements of the nonequilibrium statistical mechanics controlling mesoscopic order and disorder in many-degree-of-freedom nonlinear dynamical systems. Competing length scales and/or time scales are the underlying microscopic driving forces for many of these aspects of ''complexity.'' We illustrate the basic concepts with some model examples of classical and quantum, ordered and disordered, nonlinear systems

  9. Chaos control of Chen chaotic dynamical system

    International Nuclear Information System (INIS)

    Yassen, M.T.

    2003-01-01

    This paper is devoted to study the problem of controlling chaos in Chen chaotic dynamical system. Two different methods of control, feedback and nonfeedback methods are used to suppress chaos to unstable equilibria or unstable periodic orbits (UPO). The Lyapunov direct method and Routh-Hurwitz criteria are used to study the conditions of the asymptotic stability of the steady states of the controlled system. Numerical simulations are presented to show these results

  10. Automated design of complex dynamic systems.

    Directory of Open Access Journals (Sweden)

    Michiel Hermans

    Full Text Available Several fields of study are concerned with uniting the concept of computation with that of the design of physical systems. For example, a recent trend in robotics is to design robots in such a way that they require a minimal control effort. Another example is found in the domain of photonics, where recent efforts try to benefit directly from the complex nonlinear dynamics to achieve more efficient signal processing. The underlying goal of these and similar research efforts is to internalize a large part of the necessary computations within the physical system itself by exploiting its inherent non-linear dynamics. This, however, often requires the optimization of large numbers of system parameters, related to both the system's structure as well as its material properties. In addition, many of these parameters are subject to fabrication variability or to variations through time. In this paper we apply a machine learning algorithm to optimize physical dynamic systems. We show that such algorithms, which are normally applied on abstract computational entities, can be extended to the field of differential equations and used to optimize an associated set of parameters which determine their behavior. We show that machine learning training methodologies are highly useful in designing robust systems, and we provide a set of both simple and complex examples using models of physical dynamical systems. Interestingly, the derived optimization method is intimately related to direct collocation a method known in the field of optimal control. Our work suggests that the application domains of both machine learning and optimal control have a largely unexplored overlapping area which envelopes a novel design methodology of smart and highly complex physical systems.

  11. Some problems of dynamical systems on three dimensional manifolds

    International Nuclear Information System (INIS)

    Dong Zhenxie.

    1985-08-01

    It is important to study the dynamical systems on 3-dimensional manifolds, its importance is showing up in its close relation with our life. Because of the complication of topological structure of Dynamical systems on 3-dimensional manifolds, generally speaking, the search for 3-dynamical systems is not easier than 2-dynamical systems. This paper is a summary of the partial result of dynamical systems on 3-dimensional manifolds. (author)

  12. Modeling Asteroid Dynamics using AMUSE: First Test Cases

    NARCIS (Netherlands)

    Frantseva, Kateryna; Mueller, Michael; van der Tak, Floris; Helmich, Frank P.

    2015-01-01

    We are creating a dynamic model of the current asteroid population. The goal is to reproduce measured impact rates in the current Solar System, from which we'll derive delivery rates of water and organic material by tracing low-albedo C-class asteroids (using the measured albedo distribution from

  13. Parameter identifiability of linear dynamical systems

    Science.gov (United States)

    Glover, K.; Willems, J. C.

    1974-01-01

    It is assumed that the system matrices of a stationary linear dynamical system were parametrized by a set of unknown parameters. The question considered here is, when can such a set of unknown parameters be identified from the observed data? Conditions for the local identifiability of a parametrization are derived in three situations: (1) when input/output observations are made, (2) when there exists an unknown feedback matrix in the system and (3) when the system is assumed to be driven by white noise and only output observations are made. Also a sufficient condition for global identifiability is derived.

  14. Nonlinear dynamic macromodeling techniques for audio systems

    Science.gov (United States)

    Ogrodzki, Jan; Bieńkowski, Piotr

    2015-09-01

    This paper develops a modelling method and a models identification technique for the nonlinear dynamic audio systems. Identification is performed by means of a behavioral approach based on a polynomial approximation. This approach makes use of Discrete Fourier Transform and Harmonic Balance Method. A model of an audio system is first created and identified and then it is simulated in real time using an algorithm of low computational complexity. The algorithm consists in real time emulation of the system response rather than in simulation of the system itself. The proposed software is written in Python language using object oriented programming techniques. The code is optimized for a multithreads environment.

  15. Testing lifting systems in nuclear facilities

    International Nuclear Information System (INIS)

    Kling, H.; Laug, R.

    1984-01-01

    Lifting systems in nuclear facilities must be inspected at regular intervals after having undergone their first acceptance test. These inspections are frequently carried out by service firms which not only employ the skilled personnel required for such jobs but also make available the necessary test equipment. The inspections in particular include a number of sophisticated load tests for which test load systems have been developed to allow lifting systems to be tested so that reactor specific boundary conditions are taken into account. In view of the large number of facilities to be inspected, the test load system is a modular system. (orig.) [de

  16. Dynamic Characteristics of a New Machine for Fatigue Testing of Railway Axles – Part 2

    Directory of Open Access Journals (Sweden)

    Karel FRYDRÝŠEK

    2012-06-01

    Full Text Available There were done some proposal calculations for a new testing machine. This new testing machine is determined for a dynamic fatigue testing of railway axles. The railway axles are subjected to bending and rotation (centrifugal effects. For the right proposition of a new machine is very important to know the basic dynamic characteristics of whole system. These dynamic characteristics are solved via FEM (MSC.Marc/Mentat software in combination with SBRA (Simulation-Based Reliability Assessment Method (probabilistic Monte Carlo approach, Anthill and Python software. The proposed dimensions and springs of a new machine for fatigue testing of railway axles were used for manufacturing. Application of the SBRA method connected with FEM in these areas is a new and innovative trend in mechanics. This paper is continuation of former work (i.e. easier deterministic approach already presented in this journal in 2007.

  17. Full-Scale Dynamic Testing of Dolosse to Destruction

    DEFF Research Database (Denmark)

    Burcharth, Hans F.

    1981-01-01

    It is well known that the relative dynamic strength of unreinforced slender concrete units decreases as the size increases. Big units can resist relatively smaller movements than small units. When model tests of cover layer stability are performed the determination of the damage criterion....... The set up and the procedure of the tests, which simulate the impact from rocking of the units and from concrete pieces that are thrown against the units, are designed to make a comparison between the behaviour of units of different sizes possible. The test method is described and proposed as a standard...... exists. Different ways of improving the strength of the units are discussed on the basis of the results from tests with different types of concrete. The tests included an investigation of the influence of reinforcement, and of different types of concrete and surface cracks on the strength of the units....

  18. Scalable Molecular Dynamics for Large Biomolecular Systems

    Directory of Open Access Journals (Sweden)

    Robert K. Brunner

    2000-01-01

    Full Text Available We present an optimized parallelization scheme for molecular dynamics simulations of large biomolecular systems, implemented in the production-quality molecular dynamics program NAMD. With an object-based hybrid force and spatial decomposition scheme, and an aggressive measurement-based predictive load balancing framework, we have attained speeds and speedups that are much higher than any reported in literature so far. The paper first summarizes the broad methodology we are pursuing, and the basic parallelization scheme we used. It then describes the optimizations that were instrumental in increasing performance, and presents performance results on benchmark simulations.

  19. Structural dynamics of electronic and photonic systems

    CERN Document Server

    Suhir, Ephraim; Steinberg, David S

    2011-01-01

    The proposed book will offer comprehensive and versatile methodologies and recommendations on how to determine dynamic characteristics of typical micro- and opto-electronic structural elements (printed circuit boards, solder joints, heavy devices, etc.) and how to design a viable and reliable structure that would be able to withstand high-level dynamic loading. Particular attention will be given to portable devices and systems designed for operation in harsh environments (such as automotive, aerospace, military, etc.)  In-depth discussion from a mechanical engineer's viewpoint will be conducte

  20. Nonlinear dynamical system approaches towards neural prosthesis

    International Nuclear Information System (INIS)

    Torikai, Hiroyuki; Hashimoto, Sho

    2011-01-01

    An asynchronous discrete-state spiking neurons is a wired system of shift registers that can mimic nonlinear dynamics of an ODE-based neuron model. The control parameter of the neuron is the wiring pattern among the registers and thus they are suitable for on-chip learning. In this paper an asynchronous discrete-state spiking neuron is introduced and its typical nonlinear phenomena are demonstrated. Also, a learning algorithm for a set of neurons is presented and it is demonstrated that the algorithm enables the set of neurons to reconstruct nonlinear dynamics of another set of neurons with unknown parameter values. The learning function is validated by FPGA experiments.

  1. Order in cold ionic systems: Dynamic effects

    International Nuclear Information System (INIS)

    Schiffer, J.P.

    1988-01-01

    The present state and recent developments in Molecular Dynamics calculations modeling cooled heavy-ion beams are summarized. First, a frame of reference is established, summarizing what has happened in the past; then the properties of model systems of cold ions studied in Molecular Dynamics calculations are reviewed, with static boundary conditions with which an ordered state is revealed; finally, more recent results on such modelling, adding the complications in the (time-dependent) boundary conditions that begin to approach real storage rings (ion traps) are reported. 14 refs., 19 figs., 2 tabs

  2. Dynamical systems with applications using Maple

    CERN Document Server

    Lynch, Stephen

    2001-01-01

    "The text treats a remarkable spectrum of topics and has a little for everyone. It can serve as an introduction to many of the topics of dynamical systems, and will help even the most jaded reader, such as this reviewer, enjoy some of the interactive aspects of studying dynamics using Maple." —UK Nonlinear News (Review of First Edition) "The book will be useful for all kinds of dynamical systems courses…. [It] shows the power of using a computer algebra program to study dynamical systems, and, by giving so many worked examples, provides ample opportunity for experiments. … [It] is well written and a pleasure to read, which is helped by its attention to historical background." —Mathematical Reviews (Review of First Edition) Since the first edition of this book was published in 2001, Maple™ has evolved from Maple V into Maple 13. Accordingly, this new edition has been thoroughly updated and expanded to include more applications, examples, and exercises, all with solutions; two new chapters on neural n...

  3. Geometric phases in discrete dynamical systems

    Energy Technology Data Exchange (ETDEWEB)

    Cartwright, Julyan H.E., E-mail: julyan.cartwright@csic.es [Instituto Andaluz de Ciencias de la Tierra, CSIC–Universidad de Granada, E-18100 Armilla, Granada (Spain); Instituto Carlos I de Física Teórica y Computacional, Universidad de Granada, E-18071 Granada (Spain); Piro, Nicolas, E-mail: nicolas.piro@epfl.ch [École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne (Switzerland); Piro, Oreste, E-mail: piro@imedea.uib-csic.es [Departamento de Física, Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain); Tuval, Idan, E-mail: ituval@imedea.uib-csic.es [Mediterranean Institute for Advanced Studies, CSIC–Universitat de les Illes Balears, E-07190 Mallorca (Spain)

    2016-10-14

    In order to study the behaviour of discrete dynamical systems under adiabatic cyclic variations of their parameters, we consider discrete versions of adiabatically-rotated rotators. Parallelling the studies in continuous systems, we generalize the concept of geometric phase to discrete dynamics and investigate its presence in these rotators. For the rotated sine circle map, we demonstrate an analytical relationship between the geometric phase and the rotation number of the system. For the discrete version of the rotated rotator considered by Berry, the rotated standard map, we further explore this connection as well as the role of the geometric phase at the onset of chaos. Further into the chaotic regime, we show that the geometric phase is also related to the diffusive behaviour of the dynamical variables and the Lyapunov exponent. - Highlights: • We extend the concept of geometric phase to maps. • For the rotated sine circle map, we demonstrate an analytical relationship between the geometric phase and the rotation number. • For the rotated standard map, we explore the role of the geometric phase at the onset of chaos. • We show that the geometric phase is related to the diffusive behaviour of the dynamical variables and the Lyapunov exponent.

  4. Dynamic behavior of district heating systems

    International Nuclear Information System (INIS)

    Kunz, J.

    1994-01-01

    The goal of this study is to develop a simulation model of a hot water system taking into account the time dependent phenomena which are important for the operational management of such a system. A state of the art literature review has shown that there is no such model considering all parts from the generation of the heat at the plant to its consumption in the connected buildings so far. First, an exhaustive list of all dynamic phenomena occurring in district heating systems has been drawn and analyzed. Considering this list, this thesis proposes that a model which satisfies the criteria listed above can be developed by superposing four sub-models which are a dynamic model of the heat generation plant, a steady state model of the hydraulic calculation of the distribution network, a dynamic model of the thermal behavior of the network and a dynamic model of the heat consumers. The development of the four sub-models starts from the fundamental conservation equations for fluid systems, i.e. the conservation of mass, momentum and energy. The transformations of those general equations into simple calculation formulas show and justify the hypotheses made in the modeling process. The heat generation plant model itself is a set of sub-models: the models for steam boilers, hot water boilers and heat accumulators which take account of the dynamic evolution of the water temperature by a simple form of the energy conservation equation, as well as the steady state models for circulation pumps and pressurizers. Since the velocities in the network pipes are small, a consideration of steady states is adopted. A network model allowing to calculate the hydraulic variables in every point is adopted from the graph theory. The pressures and flow rates in the network are calculated at discrete time steps and they are considered to be constant for the duration between the time steps. (author) figs., tabs., refs

  5. Dynamical systems on networks a tutorial

    CERN Document Server

    Porter, Mason A

    2016-01-01

    This volume is a tutorial for the study of dynamical systems on networks. It discusses both methodology and models, including spreading models for social and biological contagions. The authors focus especially on “simple” situations that are analytically tractable, because they are insightful and provide useful springboards for the study of more complicated scenarios. This tutorial, which also includes key pointers to the literature, should be helpful for junior and senior undergraduate students, graduate students, and researchers from mathematics, physics, and engineering who seek to study dynamical systems on networks but who may not have prior experience with graph theory or networks. Mason A. Porter is Professor of Nonlinear and Complex Systems at the Oxford Centre for Industrial and Applied Mathematics, Mathematical Institute, University of Oxford, UK. He is also a member of the CABDyN Complexity Centre and a Tutorial Fellow of Somerville College. James P. Gleeson is Professor of Industrial and Appli...

  6. Epidemic Dynamics in Open Quantum Spin Systems

    Science.gov (United States)

    Pérez-Espigares, Carlos; Marcuzzi, Matteo; Gutiérrez, Ricardo; Lesanovsky, Igor

    2017-10-01

    We explore the nonequilibrium evolution and stationary states of an open many-body system that displays epidemic spreading dynamics in a classical and a quantum regime. Our study is motivated by recent experiments conducted in strongly interacting gases of highly excited Rydberg atoms where the facilitated excitation of Rydberg states competes with radiative decay. These systems approximately implement open quantum versions of models for population dynamics or disease spreading where species can be in a healthy, infected or immune state. We show that in a two-dimensional lattice, depending on the dominance of either classical or quantum effects, the system may display a different kind of nonequilibrium phase transition. We moreover discuss the observability of our findings in laser driven Rydberg gases with particular focus on the role of long-range interactions.

  7. Keystroke Dynamics-Based Credential Hardening Systems

    Science.gov (United States)

    Bartlow, Nick; Cukic, Bojan

    abstract Keystroke dynamics are becoming a well-known method for strengthening username- and password-based credential sets. The familiarity and ease of use of these traditional authentication schemes combined with the increased trustworthiness associated with biometrics makes them prime candidates for application in many web-based scenarios. Our keystroke dynamics system uses Breiman’s random forests algorithm to classify keystroke input sequences as genuine or imposter. The system is capable of operating at various points on a traditional ROC curve depending on application-specific security needs. As a username/password authentication scheme, our approach decreases the system penetration rate associated with compromised passwords up to 99.15%. Beyond presenting results demonstrating the credential hardening effect of our scheme, we look into the notion that a user’s familiarity to components of a credential set can non-trivially impact error rates.

  8. Brayton dynamic isotope power systems update

    International Nuclear Information System (INIS)

    Davis, K.A.; Pietsch, A.; Casagrande, R.D.

    1986-01-01

    Brayton dynamic power systems are uniquely suited for space applications. They are compact and highly efficient, offer inherent reliability due to only one moving part, and utilize a single phase and inert working fluid. Additional features include gas bearings, constant speed, and operation at essentially constant temperature. The design, utilizing an inert gas working fluid and gas bearing, is unaffected by zero gravity and can be easily started and restarted in space at low temperatures. This paper describes the salient features of the BIPS as a Dynamic Isotope Power System (DIPS), summarizes the development work to date, establishes the maturity of the design, provides an update on materials technology, and reviews systems integration considerations

  9. Dynamic graph system for a semantic database

    Science.gov (United States)

    Mizell, David

    2015-01-27

    A method and system in a computer system for dynamically providing a graphical representation of a data store of entries via a matrix interface is disclosed. A dynamic graph system provides a matrix interface that exposes to an application program a graphical representation of data stored in a data store such as a semantic database storing triples. To the application program, the matrix interface represents the graph as a sparse adjacency matrix that is stored in compressed form. Each entry of the data store is considered to represent a link between nodes of the graph. Each entry has a first field and a second field identifying the nodes connected by the link and a third field with a value for the link that connects the identified nodes. The first, second, and third fields represent the rows, column, and elements of the adjacency matrix.

  10. Individual heterogeneity generating explosive system network dynamics.

    Science.gov (United States)

    Manrique, Pedro D; Johnson, Neil F

    2018-03-01

    Individual heterogeneity is a key characteristic of many real-world systems, from organisms to humans. However, its role in determining the system's collective dynamics is not well understood. Here we study how individual heterogeneity impacts the system network dynamics by comparing linking mechanisms that favor similar or dissimilar individuals. We find that this heterogeneity-based evolution drives an unconventional form of explosive network behavior, and it dictates how a polarized population moves toward consensus. Our model shows good agreement with data from both biological and social science domains. We conclude that individual heterogeneity likely plays a key role in the collective development of real-world networks and communities, and it cannot be ignored.

  11. Individual heterogeneity generating explosive system network dynamics

    Science.gov (United States)

    Manrique, Pedro D.; Johnson, Neil F.

    2018-03-01

    Individual heterogeneity is a key characteristic of many real-world systems, from organisms to humans. However, its role in determining the system's collective dynamics is not well understood. Here we study how individual heterogeneity impacts the system network dynamics by comparing linking mechanisms that favor similar or dissimilar individuals. We find that this heterogeneity-based evolution drives an unconventional form of explosive network behavior, and it dictates how a polarized population moves toward consensus. Our model shows good agreement with data from both biological and social science domains. We conclude that individual heterogeneity likely plays a key role in the collective development of real-world networks and communities, and it cannot be ignored.

  12. Geometry and dynamics of integrable systems

    CERN Document Server

    Matveev, Vladimir

    2016-01-01

    Based on lectures given at an advanced course on integrable systems at the Centre de Recerca Matemàtica in Barcelona, these lecture notes address three major aspects of integrable systems: obstructions to integrability from differential Galois theory; the description of singularities of integrable systems on the basis of their relation to bi-Hamiltonian systems; and the generalization of integrable systems to the non-Hamiltonian settings. All three sections were written by top experts in their respective fields. Native to actual problem-solving challenges in mechanics, the topic of integrable systems is currently at the crossroads of several disciplines in pure and applied mathematics, and also has important interactions with physics. The study of integrable systems also actively employs methods from differential geometry. Moreover, it is extremely important in symplectic geometry and Hamiltonian dynamics, and has strong correlations with mathematical physics, Lie theory and algebraic geometry (including mir...

  13. Nonlinear PDEs a dynamical systems approach

    CERN Document Server

    Schneider, Guido

    2017-01-01

    This is an introductory textbook about nonlinear dynamics of PDEs, with a focus on problems over unbounded domains and modulation equations. The presentation is example-oriented, and new mathematical tools are developed step by step, giving insight into some important classes of nonlinear PDEs and nonlinear dynamics phenomena which may occur in PDEs. The book consists of four parts. Parts I and II are introductions to finite- and infinite-dimensional dynamics defined by ODEs and by PDEs over bounded domains, respectively, including the basics of bifurcation and attractor theory. Part III introduces PDEs on the real line, including the Korteweg-de Vries equation, the Nonlinear Schrödinger equation and the Ginzburg-Landau equation. These examples often occur as simplest possible models, namely as amplitude or modulation equations, for some real world phenomena such as nonlinear waves and pattern formation. Part IV explores in more detail the connections between such complicated physical systems and the reduced...

  14. Research on Generating Method of Embedded Software Test Document Based on Dynamic Model

    Science.gov (United States)

    Qu, MingCheng; Wu, XiangHu; Tao, YongChao; Liu, Ying

    2018-03-01

    This paper provides a dynamic model-based test document generation method for embedded software that provides automatic generation of two documents: test requirements specification documentation and configuration item test documentation. This method enables dynamic test requirements to be implemented in dynamic models, enabling dynamic test demand tracking to be easily generated; able to automatically generate standardized, standardized test requirements and test documentation, improved document-related content inconsistency and lack of integrity And other issues, improve the efficiency.

  15. The dynamical crossover in attractive colloidal systems

    Energy Technology Data Exchange (ETDEWEB)

    Mallamace, Francesco [Dipartimento di Fisica e Scienze della Terra, Università di Messina and CNISM, I-98168 Messina (Italy); Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Corsaro, Carmelo [Dipartimento di Fisica e Scienze della Terra, Università di Messina and CNISM, I-98168 Messina (Italy); Stanley, H. Eugene [Center for Polymer Studies and Department of Physics, Boston University, Boston, Massachusetts 02215 (United States); Mallamace, Domenico [Dipartimento di Scienze dell’Ambiente, della Sicurezza, del Territorio, degli Alimenti e della Salute, Università di Messina, I-98166 Messina (Italy); Chen, Sow-Hsin [Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2013-12-07

    We study the dynamical arrest in an adhesive hard-sphere colloidal system. We examine a micellar suspension of the Pluronic-L64 surfactant in the temperature (T) and volume fraction (ϕ) phase diagram. According to mode-coupling theory (MCT), this system is characterized by a cusp-like singularity and two glassy phases: an attractive glass (AG) phase and a repulsive glass (RG) phase. The T − ϕ phase diagram of this system as confirmed by a previous series of scattering data also exhibits a Percolation Threshold (PT) line, a reentrant behavior (AG-liquid-RG), and a glass-to-glass transition. The AG phase can be generated out of the liquid phase by using T and ϕ as control parameters. We utilize viscosity and nuclear magnetic resonance (NMR) techniques. NMR data confirm all the characteristic properties of the colloidal system phase diagram and give evidence of the onset of a fractal-like percolating structure at a precise threshold. The MCT scaling laws used to study the shear viscosity as a function of ϕ and T show in both cases a fragile-to-strong liquid glass-forming dynamic crossover (FSC) located near the percolation threshold where the clustering process is fully developed. These results suggest a larger thermodynamic generality for this phenomenon, which is usually studied only as a function of the temperature. We also find that the critical values of the control parameters, coincident with the PT line, define the locus of the FSC. In the region between the FSC and the glass transition lines the system dynamics are dominated by clustering effects. We thus demonstrate that it is possible, using the conceptual framework provided by extended mode-coupling theory, to describe the way a system approaches dynamic arrest, taking into account both cage and hopping effects.

  16. An Integrated Dynamic Weighing System Based on SCADA

    Directory of Open Access Journals (Sweden)

    Piotr Bazydło

    2015-01-01

    Full Text Available A prototyped dynamic weighing system has been presented which integrates together three advanced software environments: MATLAB, LabVIEW and iFIX SCADA. They were used for advanced signal processing, data acquisition, as well as visualization and process control. Dynamic weighing is a constantly developing field of metrology. Because of the highly complicated structure of any electronic weighing module, it is vulnerable to many sources of environmental disturbances. For this reason, there is a lot of research concerned with weighing signal processing, mechanical matters and functionality of the system. In the paper, some issues connected with dynamic weighing have been presented, and the necessity of implementing signal processing methods has been discussed. Implementation of this feature is impossible in the majority of SCADA systems. The integration of the three environments mentioned above is an attempt to create an industrial system with capabilities to deal with major dynamic weighing problems. It is innovative because it connects the industrial SCADA, laboratory/industrial product LabVIEW and MATLAB. In addition, the algorithms responsible for process control and data exchange are presented. The paper includes a description of the capabilities, performance tests, as well as benefits and drawbacks, of the system. The outcome of the research is a prototyped system and evaluation of its usefulness. (original abstract

  17. uncertain dynamic systems on time scales

    Directory of Open Access Journals (Sweden)

    V. Lakshmikantham

    1995-01-01

    Full Text Available A basic feedback control problem is that of obtaining some desired stability property from a system which contains uncertainties due to unknown inputs into the system. Despite such imperfect knowledge in the selected mathematical model, we often seek to devise controllers that will steer the system in a certain required fashion. Various classes of controllers whose design is based on the method of Lyapunov are known for both discrete [4], [10], [15], and continuous [3–9], [11] models described by difference and differential equations, respectively. Recently, a theory for what is known as dynamic systems on time scales has been built which incorporates both continuous and discrete times, namely, time as an arbitrary closed sets of reals, and allows us to handle both systems simultaneously [1], [2], [12], [13]. This theory permits one to get some insight into and better understanding of the subtle differences between discrete and continuous systems. We shall, in this paper, utilize the framework of the theory of dynamic systems on time scales to investigate the stability properties of conditionally invariant sets which are then applied to discuss controlled systems with uncertain elements. For the notion of conditionally invariant set and its stability properties, see [14]. Our results offer a new approach to the problem in question.

  18. TMACS Test Procedure TP007: System administration

    International Nuclear Information System (INIS)

    Scanlan, P.; Washburn, S.; Seghers, R.

    1994-01-01

    The TMACS Software Project Test Procedures translate the project's acceptance criteria into test steps. Software releases are certified when the affected Test Procedures are successfully performed and the customers authorize installation of these changes. This Test Procedure tests the TMACS System Administration functions

  19. Tritium systems test assembly stabilization

    International Nuclear Information System (INIS)

    Jasen, William G.; Michelotti, Roy A.; Anast, Kurt R.; Tesch, Charles

    2004-01-01

    The Tritium Systems Test Assembly (TSTA) was a facility dedicated to tritium technology Research and Development (R and D) primarily for future fusion power reactors. The facility was conceived in mid 1970's, operations commenced in early 1980's, stabilization and deactivation began in 2000 and were completed in 2003. The facility will remain in a Surveillance and Maintenance (S and M) mode until the Department of Energy (DOE) funds demolition of the facility, tentatively in 2009. A safe and stable end state was achieved by the TSTA Facility Stabilization Project (TFSP) in anticipation of long term S and M. At the start of the stabilization project, with an inventory of approximately 140 grams of tritium, the facility was designated a Hazard Category (HC) 2 Non-Reactor Nuclear facility as defined by US Department of Energy standard DOE-STD-1027-92 (1997). The TSTA facility comprises a laboratory area, supporting rooms, offices and associated laboratory space that included more than 20 major tritium handling systems. The project's focus was to reduce the tritium inventory by removing bulk tritium, tritiated water wastes, and tritium-contaminated high-inventory components. Any equipment that remained in the facility was stabilized in place. All of the gloveboxes and piping were rendered inoperative and vented to atmosphere. All equipment, and inventoried tritium contamination, remaining in the facility was left in a safe-and-stable state. The project used the End Points process as defined by the DOE Office of Environmental Management (web page http://www.em.doe.- gov/deact/epman.htmtlo) document and define the end state required for the stabilization of TSTA Facility. The End Points process added structure that was beneficial through virtually all phases of the project. At completion of the facility stabilization project the residual tritium inventory was approximately 3,000 curies, considerably less than the 1.6-gram threshold for a HC 3 facility. TSTA is now

  20. Lectures on Dynamics of Stochastic Systems

    CERN Document Server

    Klyatskin, Valery I

    2010-01-01

    Fluctuating parameters appear in a variety of physical systems and phenomena. They typically come either as random forces/sources, or advecting velocities, or media (material) parameters, like refraction index, conductivity, diffusivity, etc. Models naturally render to statistical description, where random processes and fields express the input parameters and solutions. The fundamental problem of stochastic dynamics is to identify the essential characteristics of system (its state and evolution), and relate those to the input parameters of the system and initial data. This book is a revised a

  1. Entanglement dynamics of J-aggregate systems

    Energy Technology Data Exchange (ETDEWEB)

    Thilagam, A, E-mail: Thilagam.Lohe@unisa.edu.au [Information Technology, Engineering and the Environment, Mawson Institute, University of South Australia, South Australia 5095 (Australia)

    2011-04-01

    The entanglement dynamics of one-dimensional J-aggregate systems are examined using entanglement measures such as the von Neumann entropy and Wootters concurrence. The effect of dispersion and resonance terms associated with the exciton-phonon interaction are analyzed using Green's function formalism. A probability propagator term, derived using the Markovian approximation, presents J-aggregate systems as potential channels for large scale energy propagation for a select range of parameters. We highlight the role of a critical number of coherently coupled monomer sites and two-exciton states in determining superradiance in J-aggregate systems.

  2. Control theory of digitally networked dynamic systems

    CERN Document Server

    Lunze, Jan

    2013-01-01

    The book gives an introduction to networked control systems and describes new modeling paradigms, analysis methods for event-driven, digitally networked systems, and design methods for distributed estimation and control. Networked model predictive control is developed as a means to tolerate time delays and packet loss brought about by the communication network. In event-based control the traditional periodic sampling is replaced by state-dependent triggering schemes. Novel methods for multi-agent systems ensure complete or clustered synchrony of agents with identical or with individual dynamic

  3. Classical dynamics of particles and systems

    CERN Document Server

    Marion, Jerry B

    1965-01-01

    Classical Dynamics of Particles and Systems presents a modern and reasonably complete account of the classical mechanics of particles, systems of particles, and rigid bodies for physics students at the advanced undergraduate level. The book aims to present a modern treatment of classical mechanical systems in such a way that the transition to the quantum theory of physics can be made with the least possible difficulty; to acquaint the student with new mathematical techniques and provide sufficient practice in solving problems; and to impart to the student some degree of sophistication in handl

  4. Testing Digital Electronic Protection Systems

    CERN Document Server

    Gabourin, S

    2011-01-01

    This paper outlines the core concepts and realisation of the Safe Machine Parameters Controller (SMPC) testbench, based on a VME crate and LabVIEW program. Its main goal is to ensure the correct function of the SMPC for the protection of the CERN accelerator complex. To achieve this, the tester has been built to replicate the machine environment and operation, in order to ensure that the chassis under test is completely exercised. The complexity of the task increases with the number of input combinations. This paper also outlines the benefits and weaknesses of developing a test suite independently of the hardware being tested, using the “V” approach.

  5. Limitations and corrections in measuring dynamic characteristics of structural systems

    International Nuclear Information System (INIS)

    Walter, P.L.

    1978-10-01

    The work deals with limitations encountered in measuring the dynamic characteristics of structural systems. Structural loading and response are measured by transducers possessing multiple resonant frequencies in their transfer function. In transient environments, the resultant signals from these transducers are shown to be analytically unpredictable in amplitude level and frequency content. Data recorded during nuclear effects simulation testing on structures are analyzed. Results of analysis can be generalized to any structure which encounters dynamic loading. Methods to improve the recorded data are described which can be implemented on a frequency selective basis during the measurement process. These improvements minimize data distortion attributable to the transfer characteristics of the measuring transducers

  6. Preoperational test report, primary ventilation system

    International Nuclear Information System (INIS)

    Clifton, F.T.

    1997-01-01

    This represents a preoperational test report for Primary Ventilation Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system provides vapor space filtered venting of tanks AY101, AY102, AZ101, AZ102. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System

  7. Preoperational test report, primary ventilation system

    Energy Technology Data Exchange (ETDEWEB)

    Clifton, F.T.

    1997-11-04

    This represents a preoperational test report for Primary Ventilation Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system provides vapor space filtered venting of tanks AY101, AY102, AZ101, AZ102. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

  8. Preoperational test report, vent building ventilation system

    International Nuclear Information System (INIS)

    Clifton, F.T.

    1997-01-01

    This represents a preoperational test report for Vent Building Ventilation Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system provides Heating, Ventilation, and Air Conditioning (HVAC) for the W-030 Ventilation Building. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System

  9. Study on service test procedure for SMES systems

    Energy Technology Data Exchange (ETDEWEB)

    Ren, L., E-mail: rl8868@126.co [R and D Center of Applied Superconductivity, Huazhong University of Science and Technology, Wuhan 430074 (China); Tang, Y.; Li, J.; Shi, J. [R and D Center of Applied Superconductivity, Huazhong University of Science and Technology, Wuhan 430074 (China); Hu, Y. [State Grid Electric Power Research Institute, Wuhan 430074 (China); Guo, F.; Chen, L.; Cheng, S. [R and D Center of Applied Superconductivity, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2009-10-15

    Some superconducting magnetic energy storage (SMES) systems have been developed successfully, and the function of them was verified by experiment. Considering the impact on the system security and stability when they are connected to the power system, it is important to build a standard test procedure and propose the main experimental contents for some representative superconducting devices. Based on the experimental results of a 35 kJ/7 kW conduction-cooled high-T{sub c} SMES system, which was developed by Huazhong University of Science and Technology, the test items and methods for a conduction-cooled high-T{sub c} SMES system are studied. For performance evaluation of this high-T{sub c} SMES, three superconducting magnet performance tests, power conditioning characteristic test and dynamic experiment in a simulated power system were fulfilled.

  10. Study on service test procedure for SMES systems

    International Nuclear Information System (INIS)

    Ren, L.; Tang, Y.; Li, J.; Shi, J.; Hu, Y.; Guo, F.; Chen, L.; Cheng, S.

    2009-01-01

    Some superconducting magnetic energy storage (SMES) systems have been developed successfully, and the function of them was verified by experiment. Considering the impact on the system security and stability when they are connected to the power system, it is important to build a standard test procedure and propose the main experimental contents for some representative superconducting devices. Based on the experimental results of a 35 kJ/7 kW conduction-cooled high-T c SMES system, which was developed by Huazhong University of Science and Technology, the test items and methods for a conduction-cooled high-T c SMES system are studied. For performance evaluation of this high-T c SMES, three superconducting magnet performance tests, power conditioning characteristic test and dynamic experiment in a simulated power system were fulfilled.

  11. Network Physiology: How Organ Systems Dynamically Interact.

    Science.gov (United States)

    Bartsch, Ronny P; Liu, Kang K L; Bashan, Amir; Ivanov, Plamen Ch

    2015-01-01

    We systematically study how diverse physiologic systems in the human organism dynamically interact and collectively behave to produce distinct physiologic states and functions. This is a fundamental question in the new interdisciplinary field of Network Physiology, and has not been previously explored. Introducing the novel concept of Time Delay Stability (TDS), we develop a computational approach to identify and quantify networks of physiologic interactions from long-term continuous, multi-channel physiological recordings. We also develop a physiologically-motivated visualization framework to map networks of dynamical organ interactions to graphical objects encoded with information about the coupling strength of network links quantified using the TDS measure. Applying a system-wide integrative approach, we identify distinct patterns in the network structure of organ interactions, as well as the frequency bands through which these interactions are mediated. We establish first maps representing physiologic organ network interactions and discover basic rules underlying the complex hierarchical reorganization in physiologic networks with transitions across physiologic states. Our findings demonstrate a direct association between network topology and physiologic function, and provide new insights into understanding how health and distinct physiologic states emerge from networked interactions among nonlinear multi-component complex systems. The presented here investigations are initial steps in building a first atlas of dynamic interactions among organ systems.

  12. Network Physiology: How Organ Systems Dynamically Interact

    Science.gov (United States)

    Bartsch, Ronny P.; Liu, Kang K. L.; Bashan, Amir; Ivanov, Plamen Ch.

    2015-01-01

    We systematically study how diverse physiologic systems in the human organism dynamically interact and collectively behave to produce distinct physiologic states and functions. This is a fundamental question in the new interdisciplinary field of Network Physiology, and has not been previously explored. Introducing the novel concept of Time Delay Stability (TDS), we develop a computational approach to identify and quantify networks of physiologic interactions from long-term continuous, multi-channel physiological recordings. We also develop a physiologically-motivated visualization framework to map networks of dynamical organ interactions to graphical objects encoded with information about the coupling strength of network links quantified using the TDS measure. Applying a system-wide integrative approach, we identify distinct patterns in the network structure of organ interactions, as well as the frequency bands through which these interactions are mediated. We establish first maps representing physiologic organ network interactions and discover basic rules underlying the complex hierarchical reorganization in physiologic networks with transitions across physiologic states. Our findings demonstrate a direct association between network topology and physiologic function, and provide new insights into understanding how health and distinct physiologic states emerge from networked interactions among nonlinear multi-component complex systems. The presented here investigations are initial steps in building a first atlas of dynamic interactions among organ systems. PMID:26555073

  13. Q-deformed systems and constrained dynamics

    International Nuclear Information System (INIS)

    Shabanov, S.V.

    1993-01-01

    It is shown that quantum theories of the q-deformed harmonic oscillator and one-dimensional free q-particle (a free particle on the 'quantum' line) can be obtained by the canonical quantization of classical Hamiltonian systems with commutative phase-space variables and a non-trivial symplectic structure. In the framework of this approach, classical dynamics of a particle on the q-line coincides with the one of a free particle with friction. It is argued that q-deformed systems can be treated as ordinary mechanical systems with the second-class constraints. In particular, second-class constrained systems corresponding to the q-oscillator and q-particle are given. A possibility of formulating q-deformed systems via gauge theories (first-class constrained systems) is briefly discussed. (orig.)

  14. Novel test of modified Newtonian dynamics with gas rich galaxies.

    Science.gov (United States)

    McGaugh, Stacy S

    2011-03-25

    The current cosmological paradigm, the cold dark matter model with a cosmological constant, requires that the mass-energy of the Universe be dominated by invisible components: dark matter and dark energy. An alternative to these dark components is that the law of gravity be modified on the relevant scales. A test of these ideas is provided by the baryonic Tully-Fisher relation (BTFR), an empirical relation between the observed mass of a galaxy and its rotation velocity. Here, I report a test using gas rich galaxies for which both axes of the BTFR can be measured independently of the theories being tested and without the systematic uncertainty in stellar mass that affects the same test with star dominated spirals. The data fall precisely where predicted a priori by the modified Newtonian dynamics. The scatter in the BTFR is attributable entirely to observational uncertainty, consistent with a single effective force law.

  15. International Conference on Dynamical Systems : Theory and Applications

    CERN Document Server

    2016-01-01

    The book is a collection of contributions devoted to analytical, numerical and experimental techniques of dynamical systems, presented at the international conference "Dynamical Systems: Theory and Applications," held in Lódz, Poland on December 7-10, 2015. The studies give deep insight into new perspectives in analysis, simulation, and optimization of dynamical systems, emphasizing directions for future research. Broadly outlined topics covered include: bifurcation and chaos in dynamical systems, asymptotic methods in nonlinear dynamics, dynamics in life sciences and bioengineering, original numerical methods of vibration analysis, control in dynamical systems, stability of dynamical systems, vibrations of lumped and continuous sytems, non-smooth systems, engineering systems and differential equations, mathematical approaches to dynamical systems, and mechatronics.

  16. International Conference on Dynamical Systems : Theory and Applications

    CERN Document Server

    2016-01-01

    The book is the second volume of a collection of contributions devoted to analytical, numerical and experimental techniques of dynamical systems, presented at the international conference "Dynamical Systems: Theory and Applications," held in Lódz, Poland on December 7-10, 2015. The studies give deep insight into new perspectives in analysis, simulation, and optimization of dynamical systems, emphasizing directions for future research. Broadly outlined topics covered include: bifurcation and chaos in dynamical systems, asymptotic methods in nonlinear dynamics, dynamics in life sciences and bioengineering, original numerical methods of vibration analysis, control in dynamical systems, stability of dynamical systems, vibrations of lumped and continuous sytems, non-smooth systems, engineering systems and differential equations, mathematical approaches to dynamical systems, and mechatronics.

  17. Qualification and testing of CT systems

    DEFF Research Database (Denmark)

    Bartscher, Markus; Neuschaefer-Rube, Ulrich; Illemann, Jens

    2018-01-01

    This chapter focuses on system verification and conformance to specifications. System qualification is carried out to ensure that the system and itscomponents achieve the best performance—usually corresponding to the specificationsmade by the manufacturer. Acceptance and reverification testing ar...

  18. Using system dynamics simulation for assessment of hydropower system safety

    Science.gov (United States)

    King, L. M.; Simonovic, S. P.; Hartford, D. N. D.

    2017-08-01

    Hydropower infrastructure systems are complex, high consequence structures which must be operated safely to avoid catastrophic impacts to human life, the environment, and the economy. Dam safety practitioners must have an in-depth understanding of how these systems function under various operating conditions in order to ensure the appropriate measures are taken to reduce system vulnerability. Simulation of system operating conditions allows modelers to investigate system performance from the beginning of an undesirable event to full system recovery. System dynamics simulation facilitates the modeling of dynamic interactions among complex arrangements of system components, providing outputs of system performance that can be used to quantify safety. This paper presents the framework for a modeling approach that can be used to simulate a range of potential operating conditions for a hydropower infrastructure system. Details of the generic hydropower infrastructure system simulation model are provided. A case study is used to evaluate system outcomes in response to a particular earthquake scenario, with two system safety performance measures shown. Results indicate that the simulation model is able to estimate potential measures of system safety which relate to flow conveyance and flow retention. A comparison of operational and upgrade strategies is shown to demonstrate the utility of the model for comparing various operational response strategies, capital upgrade alternatives, and maintenance regimes. Results show that seismic upgrades to the spillway gates provide the largest improvement in system performance for the system and scenario of interest.

  19. In Situ Test Study of Characteristics of Coal Mining Dynamic Load

    Directory of Open Access Journals (Sweden)

    Jiang He

    2015-01-01

    Full Text Available Combination of coal mining dynamic load and high static stress can easily induce such dynamic disasters as rock burst, coal and gas outburst, roof fall, and water inrush. In order to obtain the characteristic parameters of mining dynamic load and dynamic mechanism of coal and rock, the stress wave theory is applied to derive the relation of mining dynamic load strain rate and stress wave parameters. The in situ test was applied to study the stress wave propagation law of coal mine dynamic load by using the SOS microseismic monitoring system. An evaluation method for mining dynamic load strain rate was proposed, and the statistical evaluation was carried out for the range of strain rate. The research results show that the loading strain rate of mining dynamic load is in direct proportion to the seismic frequency of coal-rock mass and particle peak vibration velocity and is in inverse proportion to wave velocity. The high-frequency component damps faster than the low-frequency component in the shockwave propagating process; and the peak particle vibration velocity has a power functional relationship with the transmitting distance. The loading strain rate of mining dynamic load is generally less than class 10−1/s.

  20. Electromagnetic Environmental Effects System Testing

    Science.gov (United States)

    2009-09-02

    Frequency List for Ground Systems. Frequency (MHz) Polarization (POL) Modulation (MOD) Electric Field Intensity V/m 3.03 V AM 50 4 V AM 50...21 September 2009 B-6 Table B-2. Sample External RF EME Frequency List for Ground Systems. Frequency (MHz) Polarization (POL) Modulation...438 V/H AM/FM/PM 50 TOP 1-2-511 21 September 2009 B-7 Table B-2. Sample External RF EME Frequency List for Ground Systems. Frequency (MHz

  1. Energy Systems High-Pressure Test Laboratory | Energy Systems Integration

    Science.gov (United States)

    Facility | NREL Energy Systems High-Pressure Test Laboratory Energy Systems High-Pressure Test Laboratory In the Energy Systems Integration Facility's High-Pressure Test Laboratory, researchers can safely test high-pressure hydrogen components. Photo of researchers running an experiment with a hydrogen fuel

  2. DYNAMIC MAGNIFICATION OF BIOMECHANICAL SYSTEM MOTION

    Directory of Open Access Journals (Sweden)

    A. E. Pokatilov

    2017-01-01

    Full Text Available Methods for estimation of dynamic magnification pertaining to motion in biomechanics have been developed and approbаted in the paper. It has been ascertained that widely-used characteristics for evaluation of motion influence on mechanisms and machinery such as a dynamic coefficient and acceleration capacity factor become irrelevant while investigating human locomotion under elastic support conditions. The reason is an impossibility to compare human motion in case when there is a contact with elastic and rigid supports because while changing rigidity of the support exercise performing technique is also changing. In this case the technique still depends on a current state of a specific sportsman. Such situation is observed in sports gymnastics. Structure of kinematic and dynamic models for human motion has been investigated in the paper. It has been established that properties of an elastic support are reflected in models within two aspects: in an explicit form, when models have parameters of dynamic deformation for a gymnastic apparatus, and in an implicit form, when we have numerically changed parameters of human motion. The first part can be evaluated quantitatively while making comparison with calculations made in accordance with complete models. For this reason notions of selected and complete models have been introduced in the paper. It has been proposed to specify models for support and models of biomechanical system that represent models pertaining only to human locomotor system. It has been revealed that the selected models of support in kinematics and dynamics have structural difference. Kinematics specifies only parameters of elastic support deformation and dynamics specifies support parameters in an explicit form and additionally in models of human motion in an explicit form as well. Quantitative estimation of a dynamic motion magnification in kinematics and dynamics models has been given while using computing experiment for grand

  3. Mathematical modeling of earth's dynamical systems a primer

    CERN Document Server

    Slingerland, Rudy

    2011-01-01

    Mathematical Modeling of Earth's Dynamical Systems gives earth scientists the essential skills for translating chemical and physical systems into mathematical and computational models that provide enhanced insight into Earth's processes. Using a step-by-step method, the book identifies the important geological variables of physical-chemical geoscience problems and describes the mechanisms that control these variables. This book is directed toward upper-level undergraduate students, graduate students, researchers, and professionals who want to learn how to abstract complex systems into sets of dynamic equations. It shows students how to recognize domains of interest and key factors, and how to explain assumptions in formal terms. The book reveals what data best tests ideas of how nature works, and cautions against inadequate transport laws, unconstrained coefficients, and unfalsifiable models. Various examples of processes and systems, and ample illustrations, are provided. Students using this text should be f...

  4. Testing and Validation of the Dynamic Inertia Measurement Method

    Science.gov (United States)

    Chin, Alexander W.; Herrera, Claudia Y.; Spivey, Natalie D.; Fladung, William A.; Cloutier, David

    2015-01-01

    The Dynamic Inertia Measurement (DIM) method uses a ground vibration test setup to determine the mass properties of an object using information from frequency response functions. Most conventional mass properties testing involves using spin tables or pendulum-based swing tests, which for large aerospace vehicles becomes increasingly difficult and time-consuming, and therefore expensive, to perform. The DIM method has been validated on small test articles but has not been successfully proven on large aerospace vehicles. In response, the National Aeronautics and Space Administration Armstrong Flight Research Center (Edwards, California) conducted mass properties testing on an "iron bird" test article that is comparable in mass and scale to a fighter-type aircraft. The simple two-I-beam design of the "iron bird" was selected to ensure accurate analytical mass properties. Traditional swing testing was also performed to compare the level of effort, amount of resources, and quality of data with the DIM method. The DIM test showed favorable results for the center of gravity and moments of inertia; however, the products of inertia showed disagreement with analytical predictions.

  5. Dynamically variable spot size laser system

    Science.gov (United States)

    Gradl, Paul R. (Inventor); Hurst, John F. (Inventor); Middleton, James R. (Inventor)

    2012-01-01

    A Dynamically Variable Spot Size (DVSS) laser system for bonding metal components includes an elongated housing containing a light entry aperture coupled to a laser beam transmission cable and a light exit aperture. A plurality of lenses contained within the housing focus a laser beam from the light entry aperture through the light exit aperture. The lenses may be dynamically adjusted to vary the spot size of the laser. A plurality of interoperable safety devices, including a manually depressible interlock switch, an internal proximity sensor, a remotely operated potentiometer, a remotely activated toggle and a power supply interlock, prevent activation of the laser and DVSS laser system if each safety device does not provide a closed circuit. The remotely operated potentiometer also provides continuous variability in laser energy output.

  6. A Type System for Dynamic Web Documents

    DEFF Research Database (Denmark)

    Schwartzbach, Michael Ignatieff; Sandholm, Anders

    2000-01-01

    Many interactive Web services use the CGI interface for communication with clients. They will dynamically create HTML documents that are presented to the client who then resumes the interaction by submitting data through incorporated form fields. This protocol is difficult to statically type-chec...... system is based on a flow analysis of which we prove soundness. We present an efficient runtime implementation that respects the semantics of only well-typed programs. This work is fully implemented as part of the system for defining interactive Web services.......Many interactive Web services use the CGI interface for communication with clients. They will dynamically create HTML documents that are presented to the client who then resumes the interaction by submitting data through incorporated form fields. This protocol is difficult to statically type...

  7. Dynamical systems with applications using MATLAB

    CERN Document Server

    Lynch, Stephen

    2014-01-01

    This textbook, now in its second edition, provides a broad introduction to both continuous and discrete dynamical systems, the theory of which is motivated by examples from a wide range of disciplines. It emphasizes applications and simulation utilizing MATLAB®, Simulink®, the Image Processing Toolbox™, and the Symbolic Math Toolbox™, including MuPAD. Features new to the second edition include, sections on series solutions of ordinary differential equations, perturbation methods, normal forms, Gröbner bases, and chaos synchronization; chapters on image processing and binary oscillator computing; hundreds of new illustrations, examples, and exercises with solutions; and over eighty up-to-date MATLAB® program files and Simulink model files available online. These files were voted MATLAB® Central Pick of the Week in July 2013.  The hands-on approach of Dynamical Systems with Applications using MATLAB®, Second Edition, has minimal prerequisites, only requiring familiarity with ordinary differential equ...

  8. Quantum speed limits in open system dynamics.

    Science.gov (United States)

    del Campo, A; Egusquiza, I L; Plenio, M B; Huelga, S F

    2013-02-01

    Bounds to the speed of evolution of a quantum system are of fundamental interest in quantum metrology, quantum chemical dynamics, and quantum computation. We derive a time-energy uncertainty relation for open quantum systems undergoing a general, completely positive, and trace preserving evolution which provides a bound to the quantum speed limit. When the evolution is of the Lindblad form, the bound is analogous to the Mandelstam-Tamm relation which applies in the unitary case, with the role of the Hamiltonian being played by the adjoint of the generator of the dynamical semigroup. The utility of the new bound is exemplified in different scenarios, ranging from the estimation of the passage time to the determination of precision limits for quantum metrology in the presence of dephasing noise.

  9. Introduction to differential equations with dynamical systems

    CERN Document Server

    Campbell, Stephen L

    2011-01-01

    Many textbooks on differential equations are written to be interesting to the teacher rather than the student. Introduction to Differential Equations with Dynamical Systems is directed toward students. This concise and up-to-date textbook addresses the challenges that undergraduate mathematics, engineering, and science students experience during a first course on differential equations. And, while covering all the standard parts of the subject, the book emphasizes linear constant coefficient equations and applications, including the topics essential to engineering students. Stephen Campbell and Richard Haberman--using carefully worded derivations, elementary explanations, and examples, exercises, and figures rather than theorems and proofs--have written a book that makes learning and teaching differential equations easier and more relevant. The book also presents elementary dynamical systems in a unique and flexible way that is suitable for all courses, regardless of length.

  10. The dynamic state monitoring of bearings system

    Directory of Open Access Journals (Sweden)

    Marek Krynke

    2015-03-01

    Full Text Available The article discusses the methods of dynamic state monitoring of bearings system. A vibration signal contains important technical information about the machine condition and is currently the most frequently used in diagnostic bearings systems. One of the main ad-vantages of machine condition monitoring is identifying the cause of failure of the bearings and taking preventative measures, otherwise the operation of such a machine will lead to frequent replacement of the bearings. Monitoring changes in the course of the operation of machin-ery repair strategies allows keeping the conditioned state of dynamic failure conditioned preventive repairs and repairs after-failure time. In addition, the paper also presents the fundamental causes of bearing failure and identifies mechanisms related to the creation of any type of damage.

  11. Systemic Liquidity Crisis with Dynamic Haircuts

    OpenAIRE

    Sever, Can

    2014-01-01

    In this paper, using network tools, I analyse systemic impacts of liquidity shocks in interbank market in case of endogenous haircuts. Gai, Haldane and Kapadia (2011) introduce a benchmark for liquidity crisis following haircut shocks, and Gorton and Metrick (2010) reveal the evidence from 2007-09 crisis for increasing haircuts with banking panic. In the benchmark model, I endogenize and update haircuts dynamically during the period of stress. The results significantly differ from...

  12. High Performance Interactive System Dynamics Visualization

    Energy Technology Data Exchange (ETDEWEB)

    Bush, Brian W [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Brunhart-Lupo, Nicholas J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Gruchalla, Kenny M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Duckworth, Jonathan C [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-14

    This brochure describes a system dynamics simulation (SD) framework that supports an end-to-end analysis workflow that is optimized for deployment on ESIF facilities(Peregrine and the Insight Center). It includes (I) parallel and distributed simulation of SD models, (ii) real-time 3D visualization of running simulations, and (iii) comprehensive database-oriented persistence of simulation metadata, inputs, and outputs.

  13. High Performance Interactive System Dynamics Visualization

    Energy Technology Data Exchange (ETDEWEB)

    Bush, Brian W [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Brunhart-Lupo, Nicholas J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Gruchalla, Kenny M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Duckworth, Jonathan C [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-14

    This presentation describes a system dynamics simulation (SD) framework that supports an end-to-end analysis workflow that is optimized for deployment on ESIF facilities(Peregrine and the Insight Center). It includes (I) parallel and distributed simulation of SD models, (ii) real-time 3D visualization of running simulations, and (iii) comprehensive database-oriented persistence of simulation metadata, inputs, and outputs.

  14. Cosmic infinity: A dynamical system approach

    OpenAIRE

    Bouhmadi-López, Mariam; Marto, João; Morais, João; Silva, César M.

    2016-01-01

    Dynamical system techniques are extremely useful to study cosmology. It turns out that in most of the cases, we deal with finite isolated fixed points corresponding to a given cosmological epoch. However, it is equally important to analyse the asymptotic behaviour of the universe. On this paper, we show how this can be carried out for 3-forms model. In fact, we show that there are fixed points at infinity mainly by introducing appropriate compactifications and defining a new time variable tha...

  15. Minicomputer controlled test system for process control and monitoring systems

    International Nuclear Information System (INIS)

    Worster, L.D.

    A minicomputer controlled test system for testing process control and monitoring systems is described. This system, in service for over one year, has demonstrated that computerized control of such testing has a real potential for expanding the scope of the testing, improving accuracy of testing, and significantly reducing the time required to do the testing. The test system is built around a 16-bit minicomputer with 12K of memory. The system programming language is BASIC with the addition of assembly level routines for communication with the peripheral devices. The peripheral devices include a 100 channel scanner, analog-to-digital converter, visual display, and strip printer. (auth)

  16. Introduction to turbulent dynamical systems in complex systems

    CERN Document Server

    Majda, Andrew J

    2016-01-01

    This volume is a research expository article on the applied mathematics of turbulent dynamical systems through the paradigm of modern applied mathematics. It involves the blending of rigorous mathematical theory, qualitative and quantitative modeling, and novel numerical procedures driven by the goal of understanding physical phenomena which are of central importance to the field. The contents cover general framework, concrete examples, and instructive qualitative models. Accessible open problems are mentioned throughout. Topics covered include: · Geophysical flows with rotation, topography, deterministic and random forcing · New statistical energy principles for general turbulent dynamical systems, with applications · Linear statistical response theory combined with information theory to cope with model errors · Reduced low order models · Recent mathematical strategies for online data assimilation of turbulent dynamical systems as well as rigorous results for finite ensemble Kalman filters The volume wi...

  17. Network Randomization and Dynamic Defense for Critical Infrastructure Systems

    Energy Technology Data Exchange (ETDEWEB)

    Chavez, Adrian R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Martin, Mitchell Tyler [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hamlet, Jason [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Stout, William M.S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lee, Erik [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-04-01

    Critical Infrastructure control systems continue to foster predictable communication paths, static configurations, and unpatched systems that allow easy access to our nation's most critical assets. This makes them attractive targets for cyber intrusion. We seek to address these attack vectors by automatically randomizing network settings, randomizing applications on the end devices themselves, and dynamically defending these systems against active attacks. Applying these protective measures will convert control systems into moving targets that proactively defend themselves against attack. Sandia National Laboratories has led this effort by gathering operational and technical requirements from Tennessee Valley Authority (TVA) and performing research and development to create a proof-of-concept solution. Our proof-of-concept has been tested in a laboratory environment with over 300 nodes. The vision of this project is to enhance control system security by converting existing control systems into moving targets and building these security measures into future systems while meeting the unique constraints that control systems face.

  18. Ensaios estáticos de flexão e rigidez em placas do tipo sistema dinâmico do quadril (DHS Static load test on dynamic hip system (DHS plates

    Directory of Open Access Journals (Sweden)

    Anderson Freitas

    2009-01-01

    Full Text Available OBJETIVO: Avaliar isolada e comparativamente placas do tipo sistema dinâmico do quadril (DHS de dois fabricantes nacionais, analisar estatisticamente seus resultados e demonstrar a falta de determinantes para sua fabricação. MÉTODOS: Foram realizados ensaios estáticos de flexão em cinco placas DHS do fabricante I (grupo I e em igual quantidade do mesmo modelo do fabricante II (grupo II, sendo todas fabricadas em aço inoxidável austenítico ASTM F 138, com quatro furos e angulação de 135º. Utilizou-se máquina servohidráulica MTS, modelo Test Star II®, com capacidade de carga de 10 toneladas e controle de deslocamento. Foram obtidos dados da carga aplicada (P em função do deslocamento vertical do pistão (L, cuja velocidade foi 5 mm/min. Os ensaios foram interrompidos após atingir a deflexão vertical máxima especificada pelas normas dos ensaios. RESULTADOS: Grupo I: resistência de flexão, 161,4 ± 17,2 kgf rigidez, 64,5 ± 1,8 kgf/mm, ductilidade, > 25,4 mm. Grupo II: resistência de flexão, 124,7 ± 4,4, rigidez 59,6 ± 2,3, ductilidade > 25,4 mm. Para análise estatística foi adotado o teste de Mann-Whitney e a determinação de significância foi de 5% (pOBJECTIVE: To evaluate, both individually and comparatively, dynamic hip system-type plates marketed by two local manufacturers, to statistically analyze its results and show the lack of parameters for its manufacturing. METHODS: Static tests of flexion were carried out in five DHS plates of the manufacturer I (I group I and in equal quantity of the same model of the manufacturer II (I group II, being all made in stainless austenitic ASTM F 138 steel, with four holes and a 135º angle. A servo-hydraulic MTS machine, Test Star II model, was used with a load capacity of 10 tons and dislocation control. The data were obtained from the applied load (P as a function of the vertical dislocation of the piston (L, whose speed was 5mm/min. The tests were shutdown after reaching

  19. Statistical dynamics of ultradiffusion in hierarchical systems

    International Nuclear Information System (INIS)

    Gardner, S.

    1987-01-01

    In many types of disordered systems which exhibit frustration and competition, an ultrametric topology is found to exist in the space of allowable states. This ultrametric topology of states is associated with a hierarchical relaxation process called ultradiffusion. Ultradiffusion occurs in hierarchical non-linear (HNL) dynamical systems when constraints cause large scale, slow modes of motion to be subordinated to small scale, fast modes. Examples of ultradiffusion are found throughout condensed matter physics and critical phenomena (e.g. the states of spin glasses), in biophysics (e.g. the states of Hopfield networks) and in many other fields including layered computing based upon nonlinear dynamics. The statistical dynamics of ultradiffusion can be treated as a random walk on an ultrametric space. For reversible bifurcating ultrametric spaces the evolution equation governing the probability of a particle being found at site i at time t has a highly degenerate transition matrix. This transition matrix has a fractal geometry similar to the replica form proposed for spin glasses. The authors invert this fractal matrix using a recursive quad-tree (QT) method. Possible applications of hierarchical systems to communications and symbolic computing are discussed briefly

  20. Dynamic optical coupled system employing Dammann gratings

    Science.gov (United States)

    Di, Caihui; Zhou, Changhe; Ru, Huayi

    2004-10-01

    With the increasing of the number of users in optical fiber communications, fiber-to-home project has a larger market value. Then the need of dynamic optical couplers, especially of N broad-band couplers, becomes greater. Though some advanced fiber fusion techniques have been developed, they still have many shortcomings. In this paper we propose a dynamic optical coupled system employing even-numbered Dammann gratings, which have the characteristic that the phase distribution in the first half-period accurately equals to that in the second-period with π phase inversion. In our experiment, we divide a conventional even-numbered Dammann grating into two identical gratings. The system can achieve the beam splitter and combiner as the switch between them according to the relative shift between two complementary gratings. When there is no shift between the gratings, the demonstrated 1×8 dynamic optical coupler achieves good uniformity of 0.06 and insertion loss of around 10.8 dB for each channel as a splitter. When the two gratings have an accurate shift of a half-period between them, our system has a low insertion loss of 0.46 dB as a combiner at a wavelength of 1550 nm.