WorldWideScience

Sample records for non-minimum phase systems

  1. Passivity Based Stabilization of Non-minimum Phase Nonlinear Systems

    Czech Academy of Sciences Publication Activity Database

    Travieso-Torres, J.C.; Duarte-Mermoud, M.A.; Zagalak, Petr

    2009-01-01

    Roč. 45, č. 3 (2009), s. 417-426 ISSN 0023-5954 R&D Projects: GA ČR(CZ) GA102/07/1596 Institutional research plan: CEZ:AV0Z10750506 Keywords : nonlinear systems * stabilisation * passivity * state feedback Subject RIV: BC - Control Systems Theory Impact factor: 0.445, year: 2009 http://library.utia.cas.cz/separaty/2009/AS/zagalak-passivity based stabilization of non-minimum phase nonlinear systems.pdf

  2. Output Feedback Adaptive Control of Non-Minimum Phase Systems Using Optimal Control Modification

    Science.gov (United States)

    Nguyen, Nhan; Hashemi, Kelley E.; Yucelen, Tansel; Arabi, Ehsan

    2018-01-01

    This paper describes output feedback adaptive control approaches for non-minimum phase SISO systems with relative degree 1 and non-strictly positive real (SPR) MIMO systems with uniform relative degree 1 using the optimal control modification method. It is well-known that the standard model-reference adaptive control (MRAC) cannot be used to control non-SPR plants to track an ideal SPR reference model. Due to the ideal property of asymptotic tracking, MRAC attempts an unstable pole-zero cancellation which results in unbounded signals for non-minimum phase SISO systems. The optimal control modification can be used to prevent the unstable pole-zero cancellation which results in a stable adaptation of non-minimum phase SISO systems. However, the tracking performance using this approach could suffer if the unstable zero is located far away from the imaginary axis. The tracking performance can be recovered by using an observer-based output feedback adaptive control approach which uses a Luenberger observer design to estimate the state information of the plant. Instead of explicitly specifying an ideal SPR reference model, the reference model is established from the linear quadratic optimal control to account for the non-minimum phase behavior of the plant. With this non-minimum phase reference model, the observer-based output feedback adaptive control can maintain stability as well as tracking performance. However, in the presence of the mismatch between the SPR reference model and the non-minimum phase plant, the standard MRAC results in unbounded signals, whereas a stable adaptation can be achieved with the optimal control modification. An application of output feedback adaptive control for a flexible wing aircraft illustrates the approaches.

  3. Robustification and Optimization in Repetitive Control For Minimum Phase and Non-Minimum Phase Systems

    Science.gov (United States)

    Prasitmeeboon, Pitcha

    repetitive control FIR compensator. The aim is to reduce the final error level by using real time frequency response model updates to successively increase the cutoff frequency, each time creating the improved model needed to produce convergence zero error up to the higher cutoff. Non-minimum phase systems present a difficult design challenge to the sister field of Iterative Learning Control. The third topic investigates to what extent the same challenges appear in RC. One challenge is that the intrinsic non-minimum phase zero mapped from continuous time is close to the pole of repetitive controller at +1 creating behavior similar to pole-zero cancellation. The near pole-zero cancellation causes slow learning at DC and low frequencies. The Min-Max cost function over the learning rate is presented. The Min-Max can be reformulated as a Quadratically Constrained Linear Programming problem. This approach is shown to be an RC design approach that addresses the main challenge of non-minimum phase systems to have a reasonable learning rate at DC. Although it was illustrated that using the Min-Max objective improves learning at DC and low frequencies compared to other designs, the method requires model accuracy at high frequencies. In the real world, models usually have error at high frequencies. The fourth topic addresses how one can merge the quadratic penalty to the Min-Max cost function to increase robustness at high frequencies. The topic also considers limiting the Min-Max optimization to some frequencies interval and applying an FIR zero-phase low-pass filter to cutoff the learning for frequencies above that interval.

  4. Combined feedforward and model-assisted active disturbance rejection control for non-minimum phase system.

    Science.gov (United States)

    Sun, Li; Li, Donghai; Gao, Zhiqiang; Yang, Zhao; Zhao, Shen

    2016-09-01

    Control of the non-minimum phase (NMP) system is challenging, especially in the presence of modelling uncertainties and external disturbances. To this end, this paper presents a combined feedforward and model-assisted Active Disturbance Rejection Control (MADRC) strategy. Based on the nominal model, the feedforward controller is used to produce a tracking performance that has minimum settling time subject to a prescribed undershoot constraint. On the other hand, the unknown disturbances and uncertain dynamics beyond the nominal model are compensated by MADRC. Since the conventional Extended State Observer (ESO) is not suitable for the NMP system, a model-assisted ESO (MESO) is proposed based on the nominal observable canonical form. The convergence of MESO is proved in time domain. The stability, steady-state characteristics and robustness of the closed-loop system are analyzed in frequency domain. The proposed strategy has only one tuning parameter, i.e., the bandwidth of MESO, which can be readily determined with a prescribed robustness level. Some comparative examples are given to show the efficacy of the proposed method. This paper depicts a promising prospect of the model-assisted ADRC in dealing with complex systems. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  5. Fault diagnosis for non-minimum phase systems using ℋ∞ optimization

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Stoustrup, Jakob

    2001-01-01

    The analysis and design algorithms for residual generators for nonminimum phase systems are given. It is shown that the ℋ∞ optimization of residual generators applied directly to systems including nonminimum phase zeros can be very conservative. To remove this conservatism in the &Hscr...

  6. Causal Tracking Control of a Non-Minimum Phase HIL Transmission Test System

    OpenAIRE

    Wang, Pengfei

    2009-01-01

    The automotive industry has long relied on testing powertrain components in real vehicles, which causes the development process to be slow and expensive. Therefore, hardware in the loop (HIL) testing techniques are increasingly being adopted to develop electronic control units (ECU) for engine and other components of a vehicle. In this thesis, HIL testing system is developed to provide a laboratory testing environment for continuously variable transmissions (CVTs). Two induction motors were u...

  7. Adaptive Control of Non-Minimum Phase Modal Systems Using Residual Mode Filters2. Parts 1 and 2

    Science.gov (United States)

    Balas, Mark J.; Frost, Susan

    2011-01-01

    Many dynamic systems containing a large number of modes can benefit from adaptive control techniques, which are well suited to applications that have unknown parameters and poorly known operating conditions. In this paper, we focus on a direct adaptive control approach that has been extended to handle adaptive rejection of persistent disturbances. We extend this adaptive control theory to accommodate problematic modal subsystems of a plant that inhibit the adaptive controller by causing the open-loop plant to be non-minimum phase. We will modify the adaptive controller with a Residual Mode Filter (RMF) to compensate for problematic modal subsystems, thereby allowing the system to satisfy the requirements for the adaptive controller to have guaranteed convergence and bounded gains. This paper will be divided into two parts. Here in Part I we will review the basic adaptive control approach and introduce the primary ideas. In Part II, we will present the RMF methodology and complete the proofs of all our results. Also, we will apply the above theoretical results to a simple flexible structure example to illustrate the behavior with and without the residual mode filter.

  8. Dispersion theory and sum rules for the non-minimum phase problem in optical spectroscopy

    International Nuclear Information System (INIS)

    Peiponen, Kai-Erik

    2009-01-01

    Dispersion relations and sum rules for integer powers of an optical response function are given in the case of the non-minimum phase problem. These relations were obtained using the concept of the Hilbert transform and Blaschke product. The theory presented in this paper is useful both in basic and applied studies of non-minimum phase functions in optics, and also other fields of physics such as high energy physics.

  9. Observer-based attitude controller for lifting re-entry vehicle with non-minimum phase property

    Directory of Open Access Journals (Sweden)

    Wenming Nie

    2017-05-01

    Full Text Available This article concentrates on the attitude control problem for the lifting re-entry vehicle with non-minimum phase property. A novel attitude control method is proposed for this kind of lifting re-entry vehicle without assuming the internal dynamics to be measurable. First, an internal dynamics extended state observer is developed to deal with the unmeasurable problem of the internal dynamics. And then, the control scheme which adopts output feedback method is proposed by modifying the traditional output redefinition technique with internal dynamics extended state observer. This control scheme only requires the system output to be measurable, and it can still stabilize the unstable internal dynamics and track attitude commands. Besides, because of the inherent property of extended state observer in rejecting uncertainties and disturbances, the control precision of the proposed controller is higher than the controller designed with traditional output redefinition technique. Finally, the effectiveness and robustness of the proposed attitude controller are demonstrated by the simulation results.

  10. Adaptative control with non-minimum phase system. Application to level control in PWR power plant steam generator

    International Nuclear Information System (INIS)

    Bihoreau, C.

    1981-03-01

    This thesis presents the proposal for a water control level method likely to improve performance, especially at low power. Particular problems are analyzed in detail. Finally, computerized simulations are presented; they confirm the algorithm performance [fr

  11. Synthesis of adaptive traffic control discrete neminimalno-phase system

    Directory of Open Access Journals (Sweden)

    В.М. Азарсков

    2007-01-01

    Full Text Available  An adaptive approach to synthesizing the digital tracking system with direct set-point coupling is extended under conditions when a plant is non-minimum phase. Some bounded set of belonging of servo drive unknown parameters vector is believed to be known. The object’s model non-singularity condition is established. The asymptotical properties of control system are studied. Simulation results are given.

  12. Control of a perturbed under-actuated mechanical system

    KAUST Repository

    Zayane, Chadia; Laleg-Kirati, Taous-Meriem; Chemori, Ahmed

    2015-01-01

    In this work, the trajectory tracking problem for an under-actuated mechanical system in presence of unknown input disturbances is addressed. The studied inertia wheel inverted pendulum falls in the class of non minimum phase systems. The proposed

  13. Phase Control in Nonlinear Systems

    Science.gov (United States)

    Zambrano, Samuel; Seoane, Jesús M.; Mariño, Inés P.; Sanjuán, Miguel A. F.; Meucci, Riccardo

    The following sections are included: * Introduction * Phase Control of Chaos * Description of the model * Numerical exploration of phase control of chaos * Experimental evidence of phase control of chaos * Phase Control of Intermittency in Dynamical Systems * Crisis-induced intermittency and its control * Experimental setup and implementation of the phase control scheme * Phase control of the laser in the pre-crisis regime * Phase control of the intermittency after the crisis * Phase control of the intermittency in the quadratic map * Phase Control of Escapes in Open Dynamical Systems * Control of open dynamical systems * Model description * Numerical simulations and heuristic arguments * Experimental implementation in an electronic circuit * Conclusions and Discussions * Acknowledgments * References

  14. Aerospace Systems Monitor, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Proposal Title: Aerospace Systems Monitor PHASE 1 Technical Abstract: This Phase II STTR project will continue development and commercialization of the Aerospace...

  15. Composite Repair System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — GTL has developed an innovative composite repair methodology known as the Composite Repair System (CRS). In this phase I effort, CRS is being developed for the...

  16. Berry phase in entangled systems

    International Nuclear Information System (INIS)

    Bertlmann, R.A.; Hasegawa, Y.; Hiesmayr, B.C.; Durstberger, C.

    2005-01-01

    Full text: The influence of the geometric phase, in particular the Berry phase, on an entangled spin-1/2 system is studied. We discuss in detail the case, where the geometric phase is generated only by one part of the Hilbert space. We are able to cancel the effects of the dynamical phase by using the 'spin-echo' method. We analyze how the Berry phase affects the Bell angles and the maximal violation of a CHSH-Bell inequality. Furthermore, we suggest an experimental realization of our setup within neutron interferometry. It is possible to create entanglement between different degrees of freedom (spin and spatial degree of freedom) for a single neutron. The influence of the geometrical phase on the entangled neutron state is tested experimentally which is work in progress. (author)

  17. Phase transition in finite systems

    International Nuclear Information System (INIS)

    Chomaz, Ph.; Duflot, V.; Duflot, V.; Gulminelli, F.

    2000-01-01

    In this paper we present a review of selected aspects of Phase transitions in finite systems applied in particular to the liquid-gas phase transition in nuclei. We show that the problem of the non existence of boundary conditions can be solved by introducing a statistical ensemble with an averaged constrained volume. In such an ensemble the microcanonical heat capacity becomes negative in the transition region. We show that the caloric curve explicitly depends on the considered transformation of the volume with the excitation energy and so does not bear direct informations on the characteristics of the phase transition. Conversely, partial energy fluctuations are demonstrated to be a direct measure of the equation of state. Since the heat capacity has a negative branch in the phase transition region, the presence of abnormally large kinetic energy fluctuations is a signal of the liquid gas phase transition. (author)

  18. Phase transitions in finite systems

    Energy Technology Data Exchange (ETDEWEB)

    Chomaz, Ph. [Grand Accelerateur National d' Ions Lourds (GANIL), DSM-CEA / IN2P3-CNRS, 14 - Caen (France); Gulminelli, F. [Caen Univ., 14 (France). Lab. de Physique Corpusculaire

    2002-07-01

    In this series of lectures we will first review the general theory of phase transition in the framework of information theory and briefly address some of the well known mean field solutions of three dimensional problems. The theory of phase transitions in finite systems will then be discussed, with a special emphasis to the conceptual problems linked to a thermodynamical description for small, short-lived, open systems as metal clusters and data samples coming from nuclear collisions. The concept of negative heat capacity developed in the early seventies in the context of self-gravitating systems will be reinterpreted in the general framework of convexity anomalies of thermo-statistical potentials. The connection with the distribution of the order parameter will lead us to a definition of first order phase transitions in finite systems based on topology anomalies of the event distribution in the space of observations. Finally a careful study of the thermodynamical limit will provide a bridge with the standard theory of phase transitions and show that in a wide class of physical situations the different statistical ensembles are irreducibly inequivalent. (authors)

  19. Phase transitions in finite systems

    International Nuclear Information System (INIS)

    Chomaz, Ph.; Gulminelli, F.

    2002-01-01

    In this series of lectures we will first review the general theory of phase transition in the framework of information theory and briefly address some of the well known mean field solutions of three dimensional problems. The theory of phase transitions in finite systems will then be discussed, with a special emphasis to the conceptual problems linked to a thermodynamical description for small, short-lived, open systems as metal clusters and data samples coming from nuclear collisions. The concept of negative heat capacity developed in the early seventies in the context of self-gravitating systems will be reinterpreted in the general framework of convexity anomalies of thermo-statistical potentials. The connection with the distribution of the order parameter will lead us to a definition of first order phase transitions in finite systems based on topology anomalies of the event distribution in the space of observations. Finally a careful study of the thermodynamical limit will provide a bridge with the standard theory of phase transitions and show that in a wide class of physical situations the different statistical ensembles are irreducibly inequivalent. (authors)

  20. Three-phase Photovoltaic Systems

    DEFF Research Database (Denmark)

    Kerekes, Tamas; Sera, Dezso; Máthé, Lászlo

    2015-01-01

    , detailing the different photovoltaic inverter structures and topologies as well as discussing the different control layers within a grid-connected photovoltaic plant. Modulation schemes for various photovoltaic inverter topologies, grid synchronization, current control, active and reactive power control......Photovoltaic technology has experienced unprecedented growth in the last two decades, transforming from mainly off-grid niche generation to a major renewable energy technology, reaching approximately 180 GW of capacity worldwide at the end of 2014. Large photovoltaic power plants interfacing...... the grid through a three-phase power electronic converter are now well on the way to becoming a major player in the power system in many countries. Therefore, this article gives an overview of photovoltaic systems with a focus on three-phase applications, presenting these both from a hardware point of view...

  1. Enhanced IMC based PID controller design for non-minimum phase (NMP) integrating processes with time delays.

    Science.gov (United States)

    Ghousiya Begum, K; Seshagiri Rao, A; Radhakrishnan, T K

    2017-05-01

    Internal model control (IMC) with optimal H 2 minimization framework is proposed in this paper for design of proportional-integral-derivative (PID) controllers. The controller design is addressed for integrating and double integrating time delay processes with right half plane (RHP) zeros. Blaschke product is used to derive the optimal controller. There is a single adjustable closed loop tuning parameter for controller design. Systematic guidelines are provided for selection of this tuning parameter based on maximum sensitivity. Simulation studies have been carried out on various integrating time delay processes to show the advantages of the proposed method. The proposed controller provides enhanced closed loop performances when compared to recently reported methods in the literature. Quantitative comparative analysis has been carried out using the performance indices, Integral Absolute Error (IAE) and Total Variation (TV). Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  2. Phases, phase equilibria, and phase rules in low-dimensional systems

    International Nuclear Information System (INIS)

    Frolov, T.; Mishin, Y.

    2015-01-01

    We present a unified approach to thermodynamic description of one, two, and three dimensional phases and phase transformations among them. The approach is based on a rigorous definition of a phase applicable to thermodynamic systems of any dimensionality. Within this approach, the same thermodynamic formalism can be applied for the description of phase transformations in bulk systems, interfaces, and line defects separating interface phases. For both lines and interfaces, we rigorously derive an adsorption equation, the phase coexistence equations, and other thermodynamic relations expressed in terms of generalized line and interface excess quantities. As a generalization of the Gibbs phase rule for bulk phases, we derive phase rules for lines and interfaces and predict the maximum number of phases than may coexist in systems of the respective dimensionality

  3. 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

  4. Phase transition in finite systems

    International Nuclear Information System (INIS)

    Chomaz, Ph.; Duflot, V.; Duflot, V.; Gulminelli, F.

    2000-01-01

    The general problem of the definition of a phase transition without employing the thermodynamical limit is addressed. Different necessary conditions are considered and illustrated with examples from different nuclear and general physics phenomenologies. (authors)

  5. Phase transition in finite systems

    Energy Technology Data Exchange (ETDEWEB)

    Chomaz, Ph.; Duflot, V. [Grand Accelerateur National d' Ions Lourds (GANIL), 14 - Caen (France); Duflot, V.; Gulminelli, F. [Laboratoire de Physique Corpusculaire, LPC-ISMRa, CNRS-IN2P3, 14 - Caen (France)

    2000-07-01

    The general problem of the definition of a phase transition without employing the thermodynamical limit is addressed. Different necessary conditions are considered and illustrated with examples from different nuclear and general physics phenomenologies. (authors)

  6. Describing phase coexistence in systems with small phases

    International Nuclear Information System (INIS)

    Lovett, R

    2007-01-01

    Clusters of atoms can be studied in molecular beams and by computer simulation; 'liquid drops' provide elementary models for atomic nuclei and for the critical nuclei of nucleation theory. These clusters are often described in thermodynamic terms, but the behaviour of small clusters near a phase boundary is qualitatively different from the behaviour at a first order phase transition in idealized thermodynamics. In the idealized case the density and entropy show mathematically sharp discontinuities when the phase boundary is crossed. In large, but finite, systems, the phase boundaries become regions of state space wherein these properties vary rapidly but continuously. In small clusters with a large surface/volume ratio, however, the positive interfacial free energy makes it unlikely, even in states on phase boundaries, that a cluster will have a heterogeneous structure. What is actually seen in these states is a structure that fluctuates in time between homogeneous structures characteristic of the two sides of the phase boundary. That is, structural fluctuations are observed. Thermodynamics only predicts average properties; statistical mechanics is required to understand these fluctuations. Failure to distinguish thermodynamic properties and characterizations of fluctuations, particularly in the context of first order phase transitions, has led to suggestions that the classical rules for thermodynamic stability are violated in small systems and that classical thermodynamics provides an inconsistent description of these systems. Much of the confusion stems from taking statistical mechanical identifications of thermodynamic properties, explicitly developed for large systems, and applying them uncritically to small systems. There are no inconsistencies if thermodynamic properties are correctly identified and the distinction between thermodynamic properties and fluctuations is made clear

  7. The CEBAF fiber optic phase reference system

    International Nuclear Information System (INIS)

    Crawford, K.; Simrock, S.; Hovater, C.; Krycuk, A.

    1995-01-01

    The specified phase stability of the CEBAF RF distribution system is 2.9 degree rms per linac. Stability is achieved through the use of a temperature and pressure regulated coaxial drive line. Purpose of the fiber optic phase reference system is to monitor the relative phase at the beginning and ending of this drive line, between linacs, injector and separator to determine drift due to ambient temperature fluctuations. The system utilizes an Ortel 1310 nm single mode laser driving Sumitumo optical fiber to distribute a reference signal at 1497 MHz. Phase of this reference signal is compared to the 1427 MHz (LO) and the 70 MHz (IF) via a 360 degree phase detector. The detected information is then routed to the CEBAF control system for display with a specified resolution of ±0.2 degree over a 20 degree phase delta

  8. Phase-Modulated Optical Communication Systems

    CERN Document Server

    Ho, Keang-Po

    2005-01-01

    Fiber-optic communication systems have revolutionized our telecommunication infrastructures – currently, almost all telephone land-line, cellular, and internet communications must travel via some form of optical fibers. In these transmission systems, neither the phase nor frequency of the optical signal carries information – only the intensity of the signal is used. To transmit more information in a single optical carrier, the phase of the optical carrier must be explored. As a result, there is renewed interest in phase-modulated optical communications, mainly in direct-detection DPSK signals for long-haul optical communication systems. When optical amplifiers are used to maintain certain signal level among the fiber link, the system is limited by amplifier noises and fiber nonlinearities. Phase-Modulated Optical Communication Systems surveys this newly popular area, covering the following topics: The transmitter and receiver for phase-modulated coherent lightwave systems Method for performance analysis o...

  9. RF phase distribution systems at the SLC

    International Nuclear Information System (INIS)

    Jobe, R.K.; Schwarz, H.D.

    1989-04-01

    Modern large linear accelerators require RF distribution systems with minimal phase drifts and errors. Through the use of existing RF coaxial waveguides, and additional installation of phase reference cables and monitoring equipment, stable RF distribution for the SLC has been achieved. This paper discusses the design and performance of SLAC systems, and some design considerations for future colliders. 6 refs., 4 figs

  10. Two-phase flow in refrigeration systems

    CERN Document Server

    Gu, Junjie; Gan, Zhongxue

    2013-01-01

    Two-Phase Flow in Refrigeration Systems presents recent developments from the authors' extensive research programs on two-phase flow in refrigeration systems. This book covers advanced mass and heat transfer and vapor compression refrigeration systems and shows how the performance of an automotive air-conditioning system is affected through results obtained experimentally and theoretically, specifically with consideration of two-phase flow and oil concentration. The book is ideal for university postgraduate students as a textbook, researchers and professors as an academic reference book, and b

  11. Phase behavior and phase inversion for dispersant systems

    International Nuclear Information System (INIS)

    Solheim, A.; Brandvik, P.J.

    1991-06-01

    This report describes some preliminary phase behavior studies and phase inversion temperature measurements in seawater, bunker oil and dispersant. The objectives have been to find new ways of characterizing dispersants for dispersing oil spill at sea and, perhaps, to throw new lights on the mechanism of dispersion formation (oil-in-water emulsification). The work has been focussed on the relation to phase behavior and the existence of microemulsion in equilibrium with excess oil and water phases. The dispersing process is also compared to the recommended conditions for emulsion formation. When forming an oil-in-water emulsion in an industrial process, it is recommended to choose an emulsifier which gives a phase inversion temperature (PIT) which is 20 - 60 o C higher than the actual temperature for use. The emulsification process must take place close to the PIT which is the temperature at which the emulsion change from oil-in-water emulsion to water-in-oil emulsion when the system is stirred. This condition corresponds to the temperature where the phase behavior change character. The purpose has been to find out if the composition of the dispersants corresponds to the recommendations for oil-in-water emulsification. The amount of experimental work has been limited. Two kinds of experiments have been carried out. Phase behavior studies have been done for seawater, bunker oil and four different dispersants where one had an optimal composition. The phase behavior was hard to interpret and is not recommended for standard dispersants test. The other experimental technique was PIT-measurements by conductivity measurements versus temperature. 4 figs., 1 tab., 4 refs

  12. Phase Noise Compensation for OFDM Systems

    Science.gov (United States)

    Leshem, Amir; Yemini, Michal

    2017-11-01

    We describe a low complexity method for time domain compensation of phase noise in OFDM systems. We extend existing methods in several respects. First we suggest using the Karhunen-Lo\\'{e}ve representation of the phase noise process to estimate the phase noise. We then derive an improved datadirected choice of basis elements for LS phase noise estimation and present its total least square counterpart problem. The proposed method helps overcome one of the major weaknesses of OFDM systems. We also generalize the time domain phase noise compensation to the multiuser MIMO context. Finally we present simulation results using both simulated and measured phased noise. We quantify the tracking performance in the presence of residual carrier offset.

  13. Blue laser phase change recording system

    International Nuclear Information System (INIS)

    Hofmann, Holger; Dambach, S.Soeren; Richter, Hartmut

    2002-01-01

    The migration paths from DVD phase change recording with red laser to the next generation optical disk formats with blue laser and high NA optics are discussed with respect to optical aberration margins and disc capacities. A test system for the evaluation of phase change disks with more than 20 GB capacity is presented and first results of the recording performance are shown

  14. Thioaptamer Diagnostic System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — AM Biotechnologies (AM) will develop a diagnostic system in response to SBIR Topic X10.01 Reusable Diagnostic Lab Technology that will simultaneously detect and...

  15. Thioaptamer Diagnostic System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — AM Biotechnologies (AM) in partnership with Sandia National Laboratories will develop a Thioaptamer Diagnostic System (TDS) in response to Topic X10.01 Reusable...

  16. SOUL System Maturation, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Busek Co. Inc. proposes to advance the maturity of an innovative Spacecraft on Umbilical Line (SOUL) System suitable for a wide variety of applications of interest...

  17. SOUL System Maturation, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Busek Co. Inc. proposes to advance the maturity of an innovative Spacecraft on Umbilical Line (SOUL) System suitable for a wide variety of applications of interest...

  18. Structural Nervous System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — GTL's SNS technology aids in the operation of new or existing structural health monitoring (SHM) systems by integrating data and power pathways into the structure....

  19. Electronic construction collaboration system : phase III.

    Science.gov (United States)

    2011-12-01

    This phase of the electronic collaboration project involved two major efforts: 1) implementation of AEC Sync (formerly known as Attolist), a web-based project management system (WPMS), on the Broadway Viaduct Bridge Project and the Iowa Falls Arch Br...

  20. Tactile Data Entry System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Building on our successful Phase I Tactile Data Entry program, Barron Associates proposes development of a Glove-Enabled Computer Operations (GECO) system to permit...

  1. 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.

  2. Entransy in phase-change systems

    CERN Document Server

    Gu, Junjie

    2014-01-01

    Entransy in Phase-Change Systems summarizes recent developments in the area of entransy, especially on phase-change processes. This book covers new developments in the area including the great potential for energy saving for process industries, decreasing carbon dioxide emissions, reducing energy bills and improving overall efficiency of systems. This concise volume is an ideal book for engineers and scientists in energy-related industries.

  3. Phase diagram of strongly correlated Fermi systems

    International Nuclear Information System (INIS)

    Zverev, M.V.; Khodel', V.A.; Baldo, M.

    2000-01-01

    Phase transitions in uniform Fermi systems with repulsive forces between the particles caused by restructuring of quasiparticle filling n(p) are analyzed. It is found that in terms of variables, i.e. density ρ, nondimensional binding constant η, phase diagram of a strongly correlated Fermi system for rather a wide class of interactions reminds of a puff-pastry pie. Its upper part is filled with fermion condensate, the lower one - with normal Fermi-liquid. They are separated by a narrow interlayer - the Lifshits phase, characterized by the Fermi multibound surface [ru

  4. Oscillating systems with cointegrated phase processes

    DEFF Research Database (Denmark)

    Østergaard, Jacob; Rahbek, Anders; Ditlevsen, Susanne

    2017-01-01

    We present cointegration analysis as a method to infer the network structure of a linearly phase coupled oscillating system. By defining a class of oscillating systems with interacting phases, we derive a data generating process where we can specify the coupling structure of a network...... that resembles biological processes. In particular we study a network of Winfree oscillators, for which we present a statistical analysis of various simulated networks, where we conclude on the coupling structure: the direction of feedback in the phase processes and proportional coupling strength between...... individual components of the system. We show that we can correctly classify the network structure for such a system by cointegration analysis, for various types of coupling, including uni-/bi-directional and all-to-all coupling. Finally, we analyze a set of EEG recordings and discuss the current...

  5. GPS synchronized power system phase angle measurements

    Science.gov (United States)

    Wilson, Robert E.; Sterlina, Patrick S.

    1994-09-01

    This paper discusses the use of Global Positioning System (GPS) synchronized equipment for the measurement and analysis of key power system quantities. Two GPS synchronized phasor measurement units (PMU) were installed before testing. It was indicated that PMUs recorded the dynamic response of the power system phase angles when the northern California power grid was excited by the artificial short circuits. Power system planning engineers perform detailed computer generated simulations of the dynamic response of the power system to naturally occurring short circuits. The computer simulations use models of transmission lines, transformers, circuit breakers, and other high voltage components. This work will compare computer simulations of the same event with field measurement.

  6. A Systematic and Numerically Efficient Procedure for Stable Dynamic Model Inversion of LTI Systems

    NARCIS (Netherlands)

    George, K.; Verhaegen, M.; Scherpen, J.M.A.

    1999-01-01

    Output tracking via the novel Stable Dynamic model Inversion (SDI) technique, applicable to non-minimum phase systems, and which naturally takes into account the presence of noise in target time histories, is considered here. We are motivated by the typical need to replicate time signals in the

  7. Phase transition signals of finite systems

    International Nuclear Information System (INIS)

    Duflot-Flandrois, Veronique

    2001-01-01

    Phase transitions are universal properties of interacting matter. They are well described if the considered system is infinite, by using standard thermodynamics. But in the case of small systems like atomic nuclei, this formalism cannot be applied anymore. Our aim is to propose a statistical mechanics approach in order to define the thermodynamical features of small open systems subject to non-saturating forces. We concentrate in particular on the definition and characterization for such systems of phase transitions belonging to the liquid gas universality class. Theoretical and experimental observables are defined to signal the occurrence and the order of this transition without any ambiguity. One of the most relevant and experimentally accessible observables consists in the study of kinetic energy fluctuations for a fixed value of the total deposited energy. In a first order phase transition such fluctuations become anomaly high and at the same time the size distribution appears to behave critically. All our results are obtained within numerical simulations of the lattice gas model with a nearest neighbors attractive interaction. Finally we check the influence of non-saturating forces, developing the specific example of the Coulomb interaction in the nucleus. Future improvements and perspectives at this work consist in the analysis of specific effects occurring in nuclei: isospin and quantum mechanics. (author) [fr

  8. Phase diagram of Pr-P system

    International Nuclear Information System (INIS)

    Mironov, K.E.

    1981-01-01

    An area of the Pr-P system, adjoining to the Pr ordinate, is plotted up by the DTA method. Presence of P solid solution in Pr is established. Data on thermal stability of PrP, PrP 2 , PrP 5 and PrP 7 are generalized. The diagram of phase transformations in Pr-P system is plotted up proceeding from the whole complex of the data, presented. A supposition is made on a possible formation of solid solutions between the highest polyphosphide and phosphorus [ru

  9. Simulations of phase transitions in ionic systems

    International Nuclear Information System (INIS)

    Panagiotopoulos, A Z

    2005-01-01

    A review of recent simulation work in the area of phase transitions in ionic systems is presented. The vapour-liquid transition for the restricted primitive model has been studied extensively in the past decade. The critical temperature is now known to excellent accuracy and the critical density to moderate accuracy. There is also strong simulation-based evidence that the model is in the Ising universality class. Discretized lattice versions of the model are reviewed. Other systems covered are size- and charge-asymmetric electrolytes, colloid-salt mixtures, realistic salt models and charged chains. Areas of future research needs are briefly discussed

  10. Service water system aging assessment - Phase I

    International Nuclear Information System (INIS)

    Jarrell, D.B.; Zimmerman, P.W.; Gore, M.L.

    1988-01-01

    The Service Water System (SWS) represents the final heat transfer loop between decay heat generated in the nuclear core and the safe dispersal of that heat energy in the environment. It is the objective of this investigation to demonstrate that aging phenomena can be identified and quantified such that aging degradation of system components can be detected and mitigated prior to the reduction of system availability to below an acceptable threshold. The approach used during the Phase I task was to (1) perform a literature search of government and private sector reports which relate to service water, aging related degradation, and potential methodologies for analysis; (2) assemble a data base which contains all the commercial power plants in the US, their Service Water System configuration, characteristics, and water source; (3) obtain and examine the available service water data from large generic data bases, i.e. NPRDS, LER, NPE, inspection reports, and other relevant plant reference data; (4) perform a fault tree analysis of a typical plant service water systems to examine failure propagation and understand specific input requirements of probabilistic risk analyses; (5) develop an in-depth questionnaire protocol for examining the information resource at a power plant which is not available through data base query and visit a central station power plant and solicit the required information; (6) analyze the information obtained from the in-depth plant interrogation and draw contrasts and conclusions with the data base information; (7) utilize the plant information to perform an interim assessment of service water system degradation mechanisms and focus future investigations. This paper addresses the elements of this task plan numbered 1, 3, 6, and 7. The remaining items are detailed in the phase-I report

  11. Phasing of Debuncher Stochastic Cooling Transverse Systems

    International Nuclear Information System (INIS)

    Pasquinelli, Ralph

    2000-01-01

    With the higher frequency of the cooling systems in the Debuncher, a modified method of making transfer functions has been developed for transverse systems. (Measuring of the momentum systems is unchanged.) Speed in making the measurements is critical, as the beam tends to decelerate due to vacuum lifetime. In the 4-8 GHz band, the harmonics in the Debuncher are 6,700 to 13,400 times the revolution frequency. Every Hertz change in revolution frequency is multiplied by this harmonic number and becomes a frequency measurement error, which is an appreciable percent of the momentum width of the beam. It was originally thought that a momentum cooling system would be phased first so that the beam could be kept from drifting in revolution frequency. As it turned out, the momentum cooling was so effective (even with the gain turned down) that the momentum width normalized to fo became less than one Hertz on the Schottky pickup. A beam this narrow requires very precise measurement of tune and revolution frequency. It was difficult to get repeatable results. For initial measuring of the transverse arrays, relative phase and delay is all that is required, so the measurement settings outlined below will suffice. Once all input and output arrays are phased, a more precise measurement of all pickups to all kickers can be done with more points and both upper and lower side bands, as in figure 1. Settings on the network analyzer were adjusted for maximum measurement speed. Data is not analyzed until a complete set of measurements is taken. Start and stop frequencies should be chosen to be just slightly wider than the band being measured. For transverse systems, select betatron USB for the measurement type. This will make the measurement two times faster. Select 101 for the number of points, sweep time of 5 seconds, IF bandwidth 30 Hz, averages = 1. It is important during the phasing to continually measure the revolution frequency and beam width of the beam for transverse systems

  12. New photosensitive systems for volume phase holography

    Science.gov (United States)

    Bianco, Andrea; Colella, Letizia; Galli, Paola; Zanutta, Alessio; Bertarelli, Chiara

    2017-05-01

    Volume phase holographic elements are becoming attractive thanks to the large efficiency and good optical quality. They are based on photosensitive materials where a modulation of the refractive index is induced. In this paper, we highlight the strategies to obtain a change in the refractive index in a dielectric material, namely a change in the material density and/or in the molecular polarizability. Moreover, we show the results achieved for materials that undergo the photo-Fries reaction as function of the molecular structure and the illumination conditions. We also report the results on a system based on the diazo Meldrum's acid where volatile molecules are produced upon light exposure.

  13. The Geometric Phase in Quantum Systems

    International Nuclear Information System (INIS)

    Pascazio, S

    2003-01-01

    The discovery of the geometric phase is one of the most interesting and intriguing findings of the last few decades. It led to a deeper understanding of the concept of phase in quantum mechanics and motivated a surge of interest in fundamental quantum mechanical issues, disclosing unexpected applications in very diverse fields of physics. Although the key ideas underlying the existence of a purely geometrical phase had already been proposed in 1956 by Pancharatnam, it was Michael Berry who revived this issue 30 years later. The clarity of Berry's seminal paper, in 1984, was extraordinary. Research on the topic flourished at such a pace that it became difficult for non-experts to follow the many different theoretical ideas and experimental proposals which ensued. Diverse concepts in independent areas of mathematics, physics and chemistry were being applied, for what was (and can still be considered) a nascent arena for theory, experiments and technology. Although collections of papers by different authors appeared in the literature, sometimes with ample introductions, surprisingly, to the best of my knowledge, no specific and exhaustive book has ever been written on this subject. The Geometric Phase in Quantum Systems is the first thorough book on geometric phases and fills an important gap in the physical literature. Other books on the subject will undoubtedly follow. But it will take a fairly long time before other authors can cover that same variety of concepts in such a comprehensive manner. The book is enjoyable. The choice of topics presented is well balanced and appropriate. The appendices are well written, understandable and exhaustive - three rare qualities. I also find it praiseworthy that the authors decided to explicitly carry out most of the calculations, avoiding, as much as possible, the use of the joke 'after a straightforward calculation, one finds...' This was one of the sentences I used to dislike most during my undergraduate studies. A student is

  14. Nonlinear observer based phase synchronization of chaotic systems

    International Nuclear Information System (INIS)

    Meng Juan; Wang Xingyuan

    2007-01-01

    This Letter analyzes the phase synchronization problem of autonomous chaotic systems. Based on the nonlinear state observer algorithm and the pole placement technique, a phase synchronization scheme is designed. The phase synchronization of a new chaotic system is achieved by using this observer controller. Numerical simulations further demonstrate the effectiveness of the proposed phase synchronization scheme

  15. Phase and amplitude detection system for the Stanford Linear Accelerator

    International Nuclear Information System (INIS)

    Fox, J.D.; Schwarz, H.D.

    1983-01-01

    A computer controlled phase and amplitude detection system to measure and stabilize the rf power sources in the Stanford Linear Accelerator is described. This system measures the instantaneous phase and amplitude of a 1 microsecond 2856 MHz rf pulse and will be used for phase feedback control and for amplitude and phase jitter detection. This paper discusses the measurement system performance requirements for the operation of the Stanford Linear Collider, and the design and implementation of the phase and amplitude detection system. The fundamental software algorithms used in the measurement are described, as is the performance of the prototype phase and amplitude detector system

  16. Phase diagrams of Pr-C system

    International Nuclear Information System (INIS)

    Eremenko, V.N.; Velikanova, T.Ya.; Gordijchuk, O.V.

    1988-01-01

    Results of the X-ray phase, metallographic and high-temperature differential thermal analysis are used for the first time to plot a diagram of the Pr-C system state. Carbides are formed in the system: Pr 2 C 3 with the bcc-structure of the Pu 2 C 3 type and with the period a 0 = 0.85722+-0.00026 within the phase region + 2 C 3 >, a 0 0.86078+-0.00016 nm - within the region 2 C 3 >+α-PrC 2 ; dimorphous PrC 2 : α-PrC 2 with the bct-structure of the CaC 2 type and periods a 0.38517+-0.00011, c 0 = 0.64337+-0.00019 nm; β-PrC 2 with the fcc-structure, probably, of KCN type. Dicarbide melts congruently at 2320 grad. C, forming eutectics with graphite at 2254+-6 grad. C and composition of 71.5% (at.)C. It is polymorphously transformed in the phase region 2 C 3 > + 2 > at 1145+-4 grad. C, and in the region 2 >+C at 1134+-4 grad. C. Sesquicarbide melts incongruently at 1545+-4 grad. C. The eutectic reaction L ↔ + 2 C 3 > occurs at 800+-4 grad. C, the eutectic composition ∼ 15% (at.)C. The temperature of the eutectoid reaction ↔ + 2 C 3 > is 675+-6 grad C. The limiting carbon solubility in β-Pr is about 8 and in α-Pr it is about 5% (at.)

  17. A Survey of Phase Change Memory Systems

    Institute of Scientific and Technical Information of China (English)

    夏飞; 蒋德钧; 熊劲; 孙凝晖

    2015-01-01

    As the scaling of applications increases, the demand of main memory capacity increases in order to serve large working set. It is difficult for DRAM (dynamic random access memory) based memory system to satisfy the memory capacity requirement due to its limited scalability and high energy consumption. Compared to DRAM, PCM (phase change memory) has better scalability, lower energy leakage, and non-volatility. PCM memory systems have become a hot topic of academic and industrial research. However, PCM technology has the following three drawbacks: long write latency, limited write endurance, and high write energy, which raises challenges to its adoption in practice. This paper surveys architectural research work to optimize PCM memory systems. First, this paper introduces the background of PCM. Then, it surveys research efforts on PCM memory systems in performance optimization, lifetime improving, and energy saving in detail, respectively. This paper also compares and summarizes these techniques from multiple dimensions. Finally, it concludes these optimization techniques and discusses possible research directions of PCM memory systems in future.

  18. A Systematic Modelling Framework for Phase Transfer Catalyst Systems

    DEFF Research Database (Denmark)

    Anantpinijwatna, Amata; Sales-Cruz, Mauricio; Hyung Kim, Sun

    2016-01-01

    Phase-transfer catalyst systems contain two liquid phases, with a catalyst (PTC) that transfers between the phases, driving product formation in one phase and being regenerated in the other phase. Typically the reaction involves neutral species in an organic phase and regeneration involves ions i....... The application of the framework is made to two cases in order to highlight the performance and issues of activity coefficient models for predicting design and operation and the effects when different organic solvents are employed....

  19. Phase tracking system for ultra narrow bandwidth applications

    NARCIS (Netherlands)

    Hill, M.T.; Cantoni, A.

    2002-01-01

    Recent advances make it possible to mitigate a number of drawbacks of conventional phase locked loops. These advances permit the design of phase tracking systems with much improved characteristics that are sought after in modern communication system applications. A new phase tracking system is

  20. Phase coexistence and line tension in ternary lipid systems

    NARCIS (Netherlands)

    Idema, T.; Leeuwen, van J.M.J.; Storm, C.

    2009-01-01

    The ternary system consisting of cholesterol, a saturated lipid, and an unsaturated one exhibits a rich phase behavior with multiple phase coexistence regimes. Remarkably, phase separation even occurs when each of the three binary systems consisting of two of these components is a uniform mixture.

  1. Power and phase monitoring system for the lower hybrid phased array heating system on ATC machine

    International Nuclear Information System (INIS)

    Reed, B.W.

    1975-01-01

    A four waveguide phased array slow wave structure has been constructed to couple microwave energy into plasma in the ATC Tokamac at Princeton. Theory has indicated that the coupling of power into the plasma column is a strong function of the imposed fourier spectrum at the antenna aperture. To optimize heating, and to verify theoretical results, a precision amplitude and phase monitoring system has been designed and constructed. The system data output is routed to an IBM 1800 computer where the fourier spectrum in n/sub parallel/ space is computed for discrete increments of time during an RF pulse. Computer output data is used to update the adjustment of transmission line parameters in between pulses

  2. System For Characterizing Three-Phase Brushless dc Motors

    Science.gov (United States)

    Howard, David E.; Smith, Dennis A.

    1996-01-01

    System of electronic hardware and software developed to automate measurements and calculations needed to characterize electromechanical performances of three-phase brushless dc motors, associated shaft-angle sensors needed for commutation, and associated brushless tachometers. System quickly takes measurements on all three phases of motor, tachometer, and shaft-angle sensor simultaneously and processes measurements into performance data. Also useful in development and testing of motors with not only three phases but also two, four, or more phases.

  3. Control of a perturbed under-actuated mechanical system

    KAUST Repository

    Zayane, Chadia

    2015-11-05

    In this work, the trajectory tracking problem for an under-actuated mechanical system in presence of unknown input disturbances is addressed. The studied inertia wheel inverted pendulum falls in the class of non minimum phase systems. The proposed high order sliding mode control architecture including a controller and differentiator allows to track accurately the predefined trajectory and to stabilize the internal dynamics. The robustness of the proposed approach is illustrated through different perturbation and output noise configurations.

  4. Phase and amplitude control system for Stanford Linear Accelerator

    International Nuclear Information System (INIS)

    Yoo, S.J.

    1983-01-01

    The computer controlled phase and amplitude detection system measures the instantaneous phase and amplitude of a 1 micro-second 2856 MHz rf pulse at a 180 Hz rate. This will be used for phase feedback control, and also for phase and amplitude jitter measurement. The program, which was originally written by John Fox and Keith Jobe, has been modified to improve the function of the system. The software algorithms used in the measurement are described, as is the performance of the prototype phase and amplitude detector system

  5. Phase Multistability in Coupled Oscillator Systems

    DEFF Research Database (Denmark)

    Mosekilde, Erik; Postnov, D.E.; Sosnovtseva, Olga

    2003-01-01

    along the orbit of the individual oscillator. Focusing on the mechanisms underlying the appearance of phase multistability, the paper examines a variety of phase-locked patterns. In particular we demonstrate the nested structure of synchronization regions for oscillations with multicrest wave forms...

  6. The phase detection and calculation for low hybrid wave phase-feedback control system

    International Nuclear Information System (INIS)

    Liu Qiang; Liang Hao; Zhou Yongzhao; Shan Jiafang

    2008-01-01

    A method of phase detection and calculation for low hybrid wave phase-feedback control system and the implementing the algorithms on DSP cores embedded in FPGA is introduced. By taking the advantages of matlab-aided design and algorithms optimization to carry out parallel processing of multi-channel phase calculation in FPGA with rich resources, the purposed of fast phase-feedback control is achieved under the need of complicated mathematical operations. (authors)

  7. System identification on two-phase flow stability

    International Nuclear Information System (INIS)

    Wu Shaorong; Zhang Youjie; Wang Dazhong; Bo Jinghai; Wang Fei

    1996-01-01

    The theoretical principle, experimental method and results of interrelation analysis identification for the instability of two-phase flow are described. A completely new concept of test technology and method on two-phase flow stability was developed by using he theory of information science on system stability and system identification for two-phase flow stability in thermo-physics field. Application of this method would make it possible to identify instability boundary of two-phase flow under stable operation conditions of two-phase flow system. The experiment was carried out on the thermohydraulic test system HRTL-5. Using reverse repeated pseudo-random sequences of heating power as input signal sources and flow rate as response function in the test, the two-phase flow stability and stability margin of the natural circulation system are investigated. The effectiveness and feasibility of identifying two-phase flow stability by using this system identification method were experimentally demonstrated. Basic data required for mathematics modeling of two-phase flow and analysis of two-phase flow stability were obtained, which are useful for analyzing, monitoring of the system operation condition, and forecasting of two-phase flow stability in engineering system

  8. A phase one AR/C system design

    Science.gov (United States)

    Kachmar, Peter M.; Polutchko, Robert J.; Matusky, Martin; Chu, William; Jackson, William; Montez, Moises

    1991-01-01

    The Phase One AR&C System Design integrates an evolutionary design based on the legacy of previous mission successes, flight tested components from manned Rendezvous and Proximity Operations (RPO) space programs, and additional AR&C components validated using proven methods. The Phase One system has a modular, open architecture with the standardized interfaces proposed for Space Station Freedom system architecture.

  9. On analytical justification of phase synchronization in different chaotic systems

    International Nuclear Information System (INIS)

    Erjaee, G.H.

    2009-01-01

    In analytical or numerical synchronizations studies of coupled chaotic systems the phase synchronizations have less considered in the leading literatures. This article is an attempt to find a sufficient analytical condition for stability of phase synchronization in some coupled chaotic systems. The method of nonlinear feedback function and the scheme of matrix measure have been used to justify this analytical stability, and tested numerically for the existence of the phase synchronization in some coupled chaotic systems.

  10. Fiber Optic Temperature Sensors for Thermal Protection Systems, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — In Phase 1, Intelligent Fiber Optic Systems Corporation (IFOS), in collaboration with North Carolina State University, successfully demonstrated a Fiber Bragg...

  11. Social Analysis Systems (SAS2) - Phase III

    International Development Research Centre (IDRC) Digital Library (Canada)

    Scaling Up the International Impact of Action Research : Social Analysis ... up the international impact of action research : SAS phase 3; final technical report ... 000 Canadians abroad to work at the local level on various development issues.

  12. Phase-space networks of geometrically frustrated systems.

    Science.gov (United States)

    Han, Yilong

    2009-11-01

    We illustrate a network approach to the phase-space study by using two geometrical frustration models: antiferromagnet on triangular lattice and square ice. Their highly degenerated ground states are mapped as discrete networks such that the quantitative network analysis can be applied to phase-space studies. The resulting phase spaces share some comon features and establish a class of complex networks with unique Gaussian spectral densities. Although phase-space networks are heterogeneously connected, the systems are still ergodic due to the random Poisson processes. This network approach can be generalized to phase spaces of some other complex systems.

  13. Integrated thermal treatment system sudy: Phase 2, Results

    Energy Technology Data Exchange (ETDEWEB)

    Feizollahi, F.; Quapp, W.J.

    1995-08-01

    This report presents the second phase of a study on thermal treatment technologies. The study consists of a systematic assessment of nineteen thermal treatment alternatives for the contact-handled mixed low-level waste (MLLW) currently stored in the US Department of Energy complex. The treatment alternatives consist of widely varying technologies for safely destroying the hazardous organic components, reducing the volume, and preparing for final disposal of the MLLW. The alternatives considered in Phase 2 were innovative thermal treatments with nine types of primary processing units. Other variations in the study examined the effect of combustion gas, air pollution control system design, and stabilization technology for the treatment residues. The Phase 1 study, the results of which have been published as an interim report, examined ten initial thermal treatment alternatives. The Phase 2 systems were evaluated in essentially the same manner as the Phase 2 systems. The assumptions and methods were the same as for the Phase 1 study. The quantities, and physical and chemical compositions, of the input waste used in he Phase 2 systems differ from those in the Phase 1 systems, which were based on a preliminary waste input database developed at the onset of the Integrated Thermal Treatment System study. The inventory database used in the Phase 2 study incorporates the latest US Department of Energy information. All systems, both primary treatment systems and subsystem inputs, have now been evaluated using the same waste input (2,927 lb/hr).

  14. Integrated thermal treatment system sudy: Phase 2, Results

    International Nuclear Information System (INIS)

    Feizollahi, F.; Quapp, W.J.

    1995-08-01

    This report presents the second phase of a study on thermal treatment technologies. The study consists of a systematic assessment of nineteen thermal treatment alternatives for the contact-handled mixed low-level waste (MLLW) currently stored in the US Department of Energy complex. The treatment alternatives consist of widely varying technologies for safely destroying the hazardous organic components, reducing the volume, and preparing for final disposal of the MLLW. The alternatives considered in Phase 2 were innovative thermal treatments with nine types of primary processing units. Other variations in the study examined the effect of combustion gas, air pollution control system design, and stabilization technology for the treatment residues. The Phase 1 study, the results of which have been published as an interim report, examined ten initial thermal treatment alternatives. The Phase 2 systems were evaluated in essentially the same manner as the Phase 2 systems. The assumptions and methods were the same as for the Phase 1 study. The quantities, and physical and chemical compositions, of the input waste used in he Phase 2 systems differ from those in the Phase 1 systems, which were based on a preliminary waste input database developed at the onset of the Integrated Thermal Treatment System study. The inventory database used in the Phase 2 study incorporates the latest US Department of Energy information. All systems, both primary treatment systems and subsystem inputs, have now been evaluated using the same waste input (2,927 lb/hr)

  15. Single phase inverter for a three phase power generation and distribution system

    Science.gov (United States)

    Lindena, S. J.

    1976-01-01

    A breadboard design of a single-phase inverter with sinusoidal output voltage for a three-phase power generation and distribution system was developed. The three-phase system consists of three single-phase inverters, whose output voltages are connected in a delta configuration. Upon failure of one inverter the two remaining inverters will continue to deliver three-phase power. Parallel redundancy as offered by two three-phase inverters is substituted by one three-phase inverter assembly with high savings in volume, weight, components count and complexity, and a considerable increase in reliability. The following requirements must be met: (1) Each single-phase, current-fed inverter must be capable of being synchronized to a three-phase reference system such that its output voltage remains phaselocked to its respective reference voltage. (2) Each single-phase, current-fed inverter must be capable of accepting leading and lagging power factors over a range from -0.7 through 1 to +0.7.

  16. MOIDSS?- Mobile Online Intelligent Decision Support System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — GRID has had a successfully completed Phase I 'Mobile Online Intelligent Decision Support System' (MOIDSS). The system developed into a total solution that supports...

  17. Space-Ready Advanced Imaging System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — In this Phase II effort Toyon will increase the state-of-the-art for video/image systems. This will include digital image compression algorithms as well as system...

  18. Distributed Rocket Engine Testing Health Monitoring System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Leveraging the Phase I achievements of the Distributed Rocket Engine Testing Health Monitoring System (DiRETHMS) including its software toolsets and system building...

  19. Mars Ascent Vehicle Reaction Control System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — During this Phase I NASA program, Valley Tech Systems (VTS) will develop an innovative solid Reaction Control System (RCS) architecture concept design that can...

  20. Development of Phase Lock Loop System for Synchronisation of a ...

    African Journals Online (AJOL)

    Akorede

    KEYWORDS: Phase locked loop (PLL), grid synchronisation, simulations, PI regulator, hybrid system. .... system. AC. - D. C co nv erter. DC-DC converter. DC. - AC co nverter. Load ... The box named Discrete Transfer Fcn is the PI-regulator.

  1. Electronic construction collaboration system -- final phase.

    Science.gov (United States)

    2014-09-01

    This phase of the research project involved two major efforts: (1) Complete the implementation of AEC-Sync (formerly known as : Attolist) on the Iowa Falls Arch Bridge project and (2) develop a WPMS for projects under $10 million. : For the first maj...

  2. Enthalpy of phase transition and prediction of phase Equilibria in systems of glycols and glycol ethers

    OpenAIRE

    Esina, Zoya; Miroshnikov, Aleksandr; Korchuganova, Margarita

    2014-01-01

    The PCEAS model was used to study the liquid-solid and liquid-vapor phase transitions at constant pressure in systems containing glycols and glycol ethers. This method is based on minimizing the excess Gibbs energy over the solvation parameter, which takes into account the processes of association of molecules in various phases. To compute the diagrams, the data on enthalpy and phase transition temperatures of pure components are required, while the information about the interactions in the b...

  3. Optimum gain and phase for stochastic cooling systems

    International Nuclear Information System (INIS)

    Meer, S. van der.

    1984-01-01

    A detailed analysis of optimum gain and phase adjustment in stochastic cooling systems reveals that the result is strongly influenced by the beam feedback effect and that for optimum performance the system phase should change appreciably across each Schottky band. It is shown that the performance is not greatly diminished if a constant phase is adopted instead. On the other hand, the effect of mixing between pick-up and kicker (which produces a phase change similar to the optimum one) is shown to be less perturbing than is usually assumed, provided that the absolute value of the gain is not too far from the optimum value. (orig.)

  4. Reconfigurable/Reprogrammable Communications Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's latest effort in developing a common platform for space communication and navigation systems is the Space Telecommunications Radio System (STRS) standard. It...

  5. Space Radiation Intelligence System (SPRINTS), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NextGen Federal Systems proposes an innovative SPace Radiation INTelligence System (SPRINTS) which provides an interactive and web-delivered capability that...

  6. Integrated Monitoring and Surveillance System demonstration project. Phase 2 accomplishments

    International Nuclear Information System (INIS)

    Aumeier, S.E.; Walters, B.G.; Singleterry, R.C.

    1997-01-01

    The paper presents the results of the Integrated Monitoring and Surveillance System (IMSS) demonstration project Phase 2 efforts. the rationale behind IMSS development is reviewed and progress in each of the 5 basic tasks is detailed. Significant results include further development of the data acquisition system and procurement of necessary hardware/software, options and associated costs for plutonium canning systems and gloveboxes, initiation of facility modifications, determination of possibly affected facility documentation, results from sensor system trade study, and preliminary storage configuration designs. Resources invested during Phase 1 and Phase 2 are summarized and budgetary requirements for completion of Phase 3 presented. The results show that the IMSS demonstration project team has met and in many cases exceeded the commitments made for Phase 2 deliverables

  7. Maintenance Decision Support System, Phase III

    Science.gov (United States)

    2017-09-01

    The main goal of the project was to address barriers that limit NDOTs ability to implement MDSS and MMS systems. The four project tasks included: Task 1: Develop system for tracking sand and/or deicing material usage: A system that tracks where and w...

  8. An algorithm for reliability analysis of phased-mission systems

    International Nuclear Information System (INIS)

    Ma, Y.; Trivedi, K.S.

    1999-01-01

    The purpose of this paper is to describe an efficient Boolean algebraic algorithm that provides exact solution to the unreliability of a multi-phase mission system where the configurations are described through fault trees. The algorithm extends and improves the Boolean method originally proposed by Somani and Trivedi. By using the Boolean algebraic method, we provide an efficient modeling approach which avoids the state space explosion and the mapping problems that are encountered by the Markov chain approach. To calculate the exact solution of the phased-mission system with deterministic phase durations, we introduce the sum of disjoint phase products (SDPP) formula, which is a phased-extension of the sum of disjoint products (SDP) formula. Computationally, the algorithm is quite efficient because it calls an SDP generation algorithm in the early stage of the SDPP computation. In this way, the phase products generated in the early stage of the SDPP formula are guaranteed to be disjoint. Consequently, the number of the intermediate phase products is greatly reduced. In this paper, we also consider the transient analysis of the phased-mission system. Special care is needed to account for the possible latent failures at the mission phase change times. If there are more stringent success criteria just after a mission phase change time, an unreliability jump would occur at that time. Finally, the algorithm has been implemented in the software package SHARPE. With SHARPE, the complexities of the phased-mission system is made transparent to the potential users. The user can conveniently specify a phased-mission model at a high level (through fault trees) and analyze the system quantitatively

  9. Imaging phase holdup distribution of three phase flow systems using dual source gamma ray tomography

    International Nuclear Information System (INIS)

    Varma, Rajneesh; Al-Dahhan, Muthanna; O'Sullivan, Joseph

    2008-01-01

    Full text: Multiphase reaction and process systems are used in abundance in the chemical and biochemical industry. Tomography has been successfully employed to visualize the hydrodynamics of multiphase systems. Most of the tomography methods (gamma ray, x-ray and electrical capacitance and resistance) have been successfully implemented for two phase dynamic systems. However, a significant number of chemical and biochemical systems consists of dynamic three phases. Research effort directed towards the development of tomography techniques to image such dynamic system has met with partial successes for specific systems with applicability to limited operating conditions. A dual source tomography scanner has been developed that uses the 661 keV and 1332 keV photo peaks from the 137 Cs and 60 Co for imaging three phase systems. A new approach has been developed and applied that uses the polyenergetic Alternating Minimization (A-M) algorithm, developed by O'Sullivan and Benac (2007), for imaging the holdup distribution in three phases' dynamic systems. The new approach avoids the traditional post image processing approach used to determine the holdup distribution where the attenuation images of the mixed flow obtained from gamma ray photons of two different energies are used to determine the holdup of three phases. In this approach the holdup images are directly reconstructed from the gamma ray transmission data. The dual source gamma ray tomography scanner and the algorithm were validated using a three phase phantom. Based in the validation, three phase holdup studies we carried out in slurry bubble column containing gas liquid and solid phases in a dynamic state using the dual energy gamma ray tomography. The key results of the holdup distribution studies in the slurry bubble column along with the validation of the dual source gamma ray tomography system would be presented and discussed

  10. Using the phase-space imager to analyze partially coherent imaging systems: bright-field, phase contrast, differential interference contrast, differential phase contrast, and spiral phase contrast

    Science.gov (United States)

    Mehta, Shalin B.; Sheppard, Colin J. R.

    2010-05-01

    Various methods that use large illumination aperture (i.e. partially coherent illumination) have been developed for making transparent (i.e. phase) specimens visible. These methods were developed to provide qualitative contrast rather than quantitative measurement-coherent illumination has been relied upon for quantitative phase analysis. Partially coherent illumination has some important advantages over coherent illumination and can be used for measurement of the specimen's phase distribution. However, quantitative analysis and image computation in partially coherent systems have not been explored fully due to the lack of a general, physically insightful and computationally efficient model of image formation. We have developed a phase-space model that satisfies these requirements. In this paper, we employ this model (called the phase-space imager) to elucidate five different partially coherent systems mentioned in the title. We compute images of an optical fiber under these systems and verify some of them with experimental images. These results and simulated images of a general phase profile are used to compare the contrast and the resolution of the imaging systems. We show that, for quantitative phase imaging of a thin specimen with matched illumination, differential phase contrast offers linear transfer of specimen information to the image. We also show that the edge enhancement properties of spiral phase contrast are compromised significantly as the coherence of illumination is reduced. The results demonstrate that the phase-space imager model provides a useful framework for analysis, calibration, and design of partially coherent imaging methods.

  11. Dynamics of Shape Memory Alloy Systems, Phase 2

    Science.gov (United States)

    2015-12-22

    Nonlinear Dynamics and Chaos in Systems with Discontinuous Support Using a Switch Model”, DINAME 2005 - XI International Conference on Dynamic Problems in...AFRL-AFOSR-CL-TR-2016-0003 Dynamics of Shape Memory Alloy Systems , Phase 2 Marcelo Savi FUNDACAO COORDENACAO DE PROJETOS PESQUISAS E EEUDOS TECNOL...release. 2 AFOSR FINAL REPORT Grant Title: Nonlinear Dynamics of Shape Memory Alloy Systems , Phase 2 Grant #: FA9550-11-1-0284 Reporting Period

  12. Quantum trajectory approach to the geometric phase: open bipartite systems

    International Nuclear Information System (INIS)

    Yi, X X; Liu, D P; Wang, W

    2005-01-01

    Through the quantum trajectory approach, we calculate the geometric phase acquired by a bipartite system subjected to decoherence. The subsystems that compose the bipartite system interact with each other and then are entangled in the evolution. The geometric phase due to the quantum jump for both the bipartite system and its subsystems is calculated and analysed. As an example, we present two coupled spin-1/2 particles to detail the calculations

  13. AC system stabilization via phase shift transformer with thyristor commutation

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Jose Carlos de; Guimaraes, Geraldo Caixeta; Moraes, Adelio Jose [Uberlandia Univ., MG (Brazil); Abreu, Jose Policarpo G. de [Escola Federal de Engenharia de Itajuba, MG (Brazil); Oliveira, Edimar Jose de [Juiz de Fora Univ., MG (Brazil)

    1994-12-31

    This article aims to present initially the constructive and operative forms of a phase-shift autotransformer which provides both magnitude and phase angle change through thyristor commutation, including a technic to reduce the number of thyristors. Following, it is proposed a control system to make such equipment an efficient AC system stabilizing tool. It is presented some simulation results to show the operation of this transformer in an electrical system. (author) 3 refs., 11 figs., 3 tabs.

  14. Space Plastic Recycling System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Techshot's proposed Space Plastic Recycler (SPR) is an automated closed loop plastic recycling system that allows the automated conversion of disposable ISS...

  15. Rapid Automated Mission Planning System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed innovation is an automated UAS mission planning system that will rapidly identify emergency (contingency) landing sites, manage contingency routing, and...

  16. Multispectral Panoramic Imaging System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — International Electronic Machines Corporation, a leader in the design of precision imaging systems, will develop an innovative multispectral, panoramic imaging...

  17. Technology verification phase. Dynamic isotope power system. Final report

    International Nuclear Information System (INIS)

    Halsey, D.G.

    1982-01-01

    The Phase I requirements of the Kilowatt Isotope Power System (KIPS) program were to make a detailed Flight System Conceptual Design (FSCD) for an isotope fueled organic Rankine cycle power system and to build and test a Ground Demonstration System (GDS) which simulated as closely as possible the operational characteristics of the FSCD. The activities and results of Phase II, the Technology Verification Phase, of the program are reported. The objectives of this phase were to increase system efficiency to 18.1% by component development, to demonstrate system reliability by a 5000 h endurance test and to update the flight system design. During Phase II, system performance was improved from 15.1% to 16.6%, an endurance test of 2000 h was performed while the flight design analysis was limited to a study of the General Purpose Heat Source, a study of the regenerator manufacturing technique and analysis of the hardness of the system to a laser threat. It was concluded from these tests that the GDS is basically prototypic of a flight design; all components necessary for satisfactory operation were demonstrated successfully at the system level; over 11,000 total h of operation without any component failure attested to the inherent reliability of this type of system; and some further development is required, specifically in the area of performance

  18. Technology verification phase. Dynamic isotope power system. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Halsey, D.G.

    1982-03-10

    The Phase I requirements of the Kilowatt Isotope Power System (KIPS) program were to make a detailed Flight System Conceptual Design (FSCD) for an isotope fueled organic Rankine cycle power system and to build and test a Ground Demonstration System (GDS) which simulated as closely as possible the operational characteristics of the FSCD. The activities and results of Phase II, the Technology Verification Phase, of the program are reported. The objectives of this phase were to increase system efficiency to 18.1% by component development, to demonstrate system reliability by a 5000 h endurance test and to update the flight system design. During Phase II, system performance was improved from 15.1% to 16.6%, an endurance test of 2000 h was performed while the flight design analysis was limited to a study of the General Purpose Heat Source, a study of the regenerator manufacturing technique and analysis of the hardness of the system to a laser threat. It was concluded from these tests that the GDS is basically prototypic of a flight design; all components necessary for satisfactory operation were demonstrated successfully at the system level; over 11,000 total h of operation without any component failure attested to the inherent reliability of this type of system; and some further development is required, specifically in the area of performance. (LCL)

  19. Phase considerations in a rotating system

    International Nuclear Information System (INIS)

    Page, L.A.

    1978-01-01

    A neutron interferometer in constant absolute rotation will exhibit a certain phase-shift between its two beams, a phenomenon shared with the classic Sagnac or Michelson-Gale-Pearson experiments or with the modern laser-gyrocompass composed of lasers in a ring. To first order in the rotational frequency, it is possible to understand by employing only rudimentary theory, the essence of this phenomenon to any degree of relativistiness of the participating particle. This paper is mainly paedagogical, noting the similarity due to permanent rotation between photon-, electron and neutron-interferometers. Future experimentation, aside from corroborating well believed tenets, may hope with improving precision to bring new approaches to measurement of fundamental effects

  20. TWO-LAYER PHASE COMPENSATING INTERFERENCE SYSTEMS

    Directory of Open Access Journals (Sweden)

    Georgiy V. Nikandrov

    2014-09-01

    Full Text Available The paper deals with creation of optical interferential coatings, giving the possibility to form the wave front without the change of energy characteristics of the incident and reflected radiation. Correction is achieved due to the layer, which thickness is a function of coordinate of an optical element surface. Selection technique is suggested for refractive index materials, forming two-layer interference coating that creates a coating with a constant coefficient of reflection on the surface of the optical element. By this procedure the change of coefficient of reflection for the optical element surface, arising because of the variable thickness is eliminated. Magnesium oxide and zirconium dioxide were used as the film-forming materials. The paper presents experimentally obtained thickness distribution of the layer, which is a part of the phase compensating coating. A new class of optical coatings proposed in the paper can find its application for correcting the form of a wave front.

  1. System design description for master equipment list, phase I

    International Nuclear Information System (INIS)

    Sandoval, J.D.

    1997-01-01

    This System Design Description (SDD) is for the Master Equipment List Phase I (MEL). It has been prepared following the WI-IC-CM-3-10, ''Software Practices,'' (Ref. 6). This SDD describes the internal design for implementation of the MEL Phase I

  2. A phase locked neutron chopper rotor drive system

    International Nuclear Information System (INIS)

    Wallace-Sims, G.R.

    1980-09-01

    A system is described for synchronising up to four neutron chopper rotors to an externally generated master pulse source. Phasing is adjustable in 1 0 steps from 0 to 360 0 relative to the master pulses. Additionally a pulse adjustable in phase is generated for initiating time of flight analyser equipment. (author)

  3. Advanced Mars Water Acquisition System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The Advanced Mars Water Acquisition System (AMWAS) recovers and purifies water from Mars soils for oxygen and fuel production, life support, food production, and...

  4. Wearable Health Monitoring Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this proposal is to demonstrate the feasibility of producing a wearable health monitoring system for the human body that is functional, comfortable,...

  5. Electronic construction collaboration system -- phase II.

    Science.gov (United States)

    2010-06-01

    During the first year of research, work was completed to identify Iowa DOT needs for web-based project management system (WPMS) : and evaluate how commercially available solutions could meet these needs. Researchers also worked to pilot test custom d...

  6. Deep Space Cryocooler System (DSCS), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — As NASA missions continue to extend the horizon beyond near-Earth missions, higher performance systems must evolve to address the challenges of reduced power...

  7. Enhanced Brine Dewatering System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The purpose of the Enhanced Brine Dewatering System (EBDS) is to provide an easily scalable means of completely recovering usable water from byproducts created by...

  8. Mars Aqueous Processing System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The Mars Aqueous Processing System (MAPS) is a novel technology for recovering oxygen, iron, and other constituents from lunar and Mars soils. The closed-loop...

  9. Helium-Hydrogen Recovery System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Immense quantities of expensive liquefied helium are required at Stennis and Kennedy Space Centers for pre-cooling rocket engine propellant systems prior to filling...

  10. Minimum Cost Nanosatellite Launch System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Delta Velocity Corporation proposes the development of a very low cost, highly responsive nanosat launch system. We propose to develop an integrated propulsion...

  11. Plenoptic Attitude Monitoring System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA is seeking an optical system capable of analyzing the attitude of wind tunnel models in real time, with a high angular resolution and robustness. To address...

  12. Wearable Health Monitoring Systems, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this proposal is to demonstrate the feasibility of producing a wearable health monitoring system for the human body that is functional, comfortable,...

  13. System Engineering Process Realization Toolkit, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA faces many systems engineering challenges as it seeks to conduct exploration and science missions concurrently. One such challenge is implementing a repeatable...

  14. Advanced Green Micropropulsion System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Systima in collaboration with University of Washington is developing a high performance injection system for advanced green monopropellant AF-M315E micropropulsion...

  15. Ground Enterprise Management System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Spacecraft ground systems are on the cusp of achieving "plug-and-play" capability, i.e., they are approaching the state in which the various components can be...

  16. Enhanced Brine Dewatering System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The purpose of the Enhanced Brine Dewatering System (EBDS) is to provide a scalable means of completely recovering usable water from byproducts created by reverse...

  17. Phase transitions in two-dimensional systems

    International Nuclear Information System (INIS)

    Salinas, S.R.A.

    1983-01-01

    Some experiences are related using synchrotron radiation beams, to characterize solid-liquid (fusion) and commensurate solid-uncommensurate solid transitions in two-dimensional systems. Some ideas involved in the modern theories of two-dimensional fusion are shortly exposed. The systems treated consist of noble gases (Kr,Ar,Xe) adsorbed in the basal plane of graphite and thin films formed by some liquid crystal shells. (L.C.) [pt

  18. Phased mission analysis of maintained systems

    International Nuclear Information System (INIS)

    Terpstra, K.

    1984-09-01

    The present study is devoted to system reliability and is mainly directed to the quantitative evaluation of accident sequences. Event tree methodology and fault tree analysis are applied as basic techniques. It introduces a new methodology for the calculation of the probability of occurrence of an accident sequence. This new methodology takes correctly into account shared equipment dependencies between the different systems present in an accident sequence. Since large and/or complex systems may contain a large number of minimal cut sets (sometimes millions of it), it is not possible as a rule to obtain the exact analytical solution. Therefore, upper and lower bounds for the probability of occurrence of an accident sequence are presented. Calculation results show that this probability is under-estimated if system dependencies are not fully taken into account. The new methodology also offers the possibility to get insight into the degree of dependency between systems based on quantitative calculations. To make the methodology manageable for complex systems, it is implemented in the reliability computer program PHAMISS. This program is written in FORTRAN-IV for the CDC-Cyber 175. PHAMISS is users friendly and has proven to be a fast and efficient program. (Auth.)

  19. Wigner Functions for the Bateman System on Noncommutative Phase Space

    Science.gov (United States)

    Heng, Tai-Hua; Lin, Bing-Sheng; Jing, Si-Cong

    2010-09-01

    We study an important dissipation system, i.e. the Bateman model on noncommutative phase space. Using the method of deformation quantization, we calculate the Exp functions, and then derive the Wigner functions and the corresponding energy spectra.

  20. Wigner Functions for the Bateman System on Noncommutative Phase Space

    International Nuclear Information System (INIS)

    Tai-Hua, Heng; Bing-Sheng, Lin; Si-Cong, Jing

    2010-01-01

    We study an important dissipation system, i.e. the Bateman model on noncommutative phase space. Using the method of deformation quantization, we calculate the Exp functions, and then derive the Wigner functions and the corresponding energy spectra

  1. Open System of Agile Ground Stations, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The Phase I effort demonstrated, through actual development and tests with a spacecraft system, the technical and programmatic feasibility of developing, within the...

  2. Load compensation for single phase system using series active filter ...

    African Journals Online (AJOL)

    Load compensation for single phase system using series active filter. ... KK Mishra, R Gupta ... load varies from time to time, the non linear load ranging from voltage source type harmonic load (VSHL) dominant to current source type harmonic ...

  3. WDM Phase-Modulated Millimeter-Wave Fiber Systems

    DEFF Research Database (Denmark)

    Yu, Xianbin; Prince, Kamau; Gibbon, Timothy Braidwood

    2012-01-01

    This chapter presents a computer simulation case study of two typical WDM phase-modulated millimeter-wave systems. The phase-modulated 60 GHz fiber multi-channel transmission systems employ single sideband (SSB) and double sideband subcarrier modulation (DSB-SC) schemes and present one of the lat......This chapter presents a computer simulation case study of two typical WDM phase-modulated millimeter-wave systems. The phase-modulated 60 GHz fiber multi-channel transmission systems employ single sideband (SSB) and double sideband subcarrier modulation (DSB-SC) schemes and present one...... of the latest research efforts in the rapidly emerging Radio-over-Fiber (RoF) application space for in-house access networks....

  4. Road Transportable Analytical Laboratory system. Phase 1

    Energy Technology Data Exchange (ETDEWEB)

    Finger, S.M.; Keith, V.F.; Spertzel, R.O.; De Avila, J.C.; O`Donnell, M.; Vann, R.L.

    1993-09-01

    This developmental effort clearly shows that a Road Transportable Analytical Laboratory System is a worthwhile and achievable goal. The RTAL is designed to fully analyze (radioanalytes, and organic and inorganic chemical analytes) 20 samples per day at the highest levels of quality assurance and quality control. It dramatically reduces the turnaround time for environmental sample analysis from 45 days (at a central commercial laboratory) to 1 day. At the same time each RTAL system will save the DOE over $12 million per year in sample analysis costs compared to the costs at a central commercial laboratory. If RTAL systems were used at the eight largest DOE facilities (at Hanford, Savannah River, Fernald, Oak Ridge, Idaho, Rocky Flats, Los Alamos, and the Nevada Test Site), the annual savings would be $96,589,000. The DOE`s internal study of sample analysis needs projects 130,000 environmental samples requiring analysis in FY 1994, clearly supporting the need for the RTAL system. The cost and time savings achievable with the RTAL system will accelerate and improve the efficiency of cleanup and remediation operations throughout the DOE complex.

  5. Integrated thermal treatment system study -- Phase 2 results. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Feizollahi, F.; Quapp, W.J.

    1996-02-01

    This report presents the second phase of a study on thermal treatment technologies. The study consists of a systematic assessment of nineteen thermal treatment alternatives for the contact-handled mixed low-level waste (MLLW) currently stored in the US Department of Energy complex. The treatment alternatives consist of widely varying technologies for safely destroying the hazardous organic components, reducing the volume, and preparing for final disposal of the MLLW. The alternatives considered in Phase 2 were innovative thermal treatments with nine types of primary processing units. Other variations in the study examined the effect of combustion gas, air pollution control system design, and stabilization technology for the treatment residues. The Phase 1 study examined ten initial thermal treatment alternatives. The Phase 2 systems were evaluated in essentially the same manner as the Phase 1 systems. The alternatives evaluated were: rotary kiln, slagging kiln, plasma furnace, plasma gasification, molten salt oxidation, molten metal waste destruction, steam gasification, Joule-heated vitrification, thermal desorption and mediated electrochemical oxidation, and thermal desorption and supercritical water oxidation. The quantities, and physical and chemical compositions, of the input waste used in the Phase 2 systems differ from those in the Phase 1 systems, which were based on a preliminary waste input database developed at the onset of the Integrated Thermal Treatment System study. The inventory database used in the Phase 2 study incorporates the latest US Department of Energy information. All systems, both primary treatment systems and subsystem inputs, have now been evaluated using the same waste input (2,927 lb/hr). 28 refs., 88 figs., 41 tabs.

  6. Negative heat capacity at phase-separation in macroscopic systems

    OpenAIRE

    Gross, D. H. E.

    2005-01-01

    Systems with long-range as well with short-range interactions should necessarily have a convex entropy S(E) at proper phase transitions of first order, i.e. when a separation of phases occurs. Here the microcanonical heat capacity c(E)= -\\frac{(\\partial S/\\partial E)^2}{\\partial^2S/\\partial E^2} is negative. This should be observable even in macroscopic systems when energy fluctuations with the surrounding world can be sufficiently suppressed.

  7. Integrated thermal treatment system study -- Phase 2 results. Revision 1

    International Nuclear Information System (INIS)

    Feizollahi, F.; Quapp, W.J.

    1996-02-01

    This report presents the second phase of a study on thermal treatment technologies. The study consists of a systematic assessment of nineteen thermal treatment alternatives for the contact-handled mixed low-level waste (MLLW) currently stored in the US Department of Energy complex. The treatment alternatives consist of widely varying technologies for safely destroying the hazardous organic components, reducing the volume, and preparing for final disposal of the MLLW. The alternatives considered in Phase 2 were innovative thermal treatments with nine types of primary processing units. Other variations in the study examined the effect of combustion gas, air pollution control system design, and stabilization technology for the treatment residues. The Phase 1 study examined ten initial thermal treatment alternatives. The Phase 2 systems were evaluated in essentially the same manner as the Phase 1 systems. The alternatives evaluated were: rotary kiln, slagging kiln, plasma furnace, plasma gasification, molten salt oxidation, molten metal waste destruction, steam gasification, Joule-heated vitrification, thermal desorption and mediated electrochemical oxidation, and thermal desorption and supercritical water oxidation. The quantities, and physical and chemical compositions, of the input waste used in the Phase 2 systems differ from those in the Phase 1 systems, which were based on a preliminary waste input database developed at the onset of the Integrated Thermal Treatment System study. The inventory database used in the Phase 2 study incorporates the latest US Department of Energy information. All systems, both primary treatment systems and subsystem inputs, have now been evaluated using the same waste input (2,927 lb/hr). 28 refs., 88 figs., 41 tabs

  8. Interactive Model-Centric Systems Engineering (IMCSE) Phase 5

    Science.gov (United States)

    2018-02-28

    Interactive Model-Centric Systems Engineering (IMCSE) Phase 5 Technical Report SERC-2018-TR-104 Feb 28, 2018 Principal Investigator...Date February 28, 2018 Copyright © 2018 Stevens Institute of Technology, Systems Engineering ...Research Center The Systems Engineering Research Center (SERC) is a federally funded University Affiliated Research Center managed by Stevens

  9. ESR imaging investigations of two-phase systems.

    Science.gov (United States)

    Herrmann, Werner; Stösser, Reinhard; Borchert, Hans-Hubert

    2007-06-01

    The possibilities of electron spin resonance (ESR) and electron spin resonance imaging (ESRI) for investigating the properties of the spin probes TEMPO and TEMPOL in two-phase systems have been examined in the systems water/n-octanol, Miglyol/Miglyol, and Precirol/Miglyol. Phases and regions of the phase boundary could be mapped successfully by means of the isotropic hyperfine coupling constants, and, moreover, the quantification of rotational and lateral diffusion of the spin probes was possible. For the quantitative treatment of the micropolarity, a simplified empirical model was established on the basis of the Nernst distribution and the experimentally determined isotropic hyperfine coupling constants. The model does not only describe the summarized micropolarities of coexisting phases, but also the region of the phase boundary, where solvent molecules of different polarities and tendencies to form hydrogen bonds compete to interact with the NO group of the spin probe. Copyright 2007 John Wiley & Sons, Ltd.

  10. Heat storage system utilizing phase change materials government rights

    Science.gov (United States)

    Salyer, Ival O.

    2000-09-12

    A thermal energy transport and storage system is provided which includes an evaporator containing a mixture of a first phase change material and a silica powder, and a condenser containing a second phase change material. The silica powder/PCM mixture absorbs heat energy from a source such as a solar collector such that the phase change material forms a vapor which is transported from the evaporator to the condenser, where the second phase change material melts and stores the heat energy, then releases the energy to an environmental space via a heat exchanger. The vapor is condensed to a liquid which is transported back to the evaporator. The system allows the repeated transfer of thermal energy using the heat of vaporization and condensation of the phase change material.

  11. Phase separation in fermionic systems with particle–hole asymmetry

    International Nuclear Information System (INIS)

    Montorsi, Arianna

    2008-01-01

    We determine the ground-state phase diagram of a Hubbard Hamiltonian with correlated hopping, which is asymmetric under particle–hole transform. By lowering the repulsive Coulomb interaction U at appropriate filling and interaction parameters, the ground state separates into hole and electron conducting phases: two different wavevectors characterize the system and charge–charge correlations become incommensurate. By further decreasing U another transition occurs at which the hole conducting region becomes insulating, and conventional phase separation takes place. Finally, for negative U the whole system eventually becomes a paired insulator. It is speculated that such behavior could be at the origin of the incommensurate superconducting phase recently discovered in the 1D Hirsch model. The exact phase boundaries are calculated in one dimension. (letter)

  12. The geometric phase in two-level atomic systems

    International Nuclear Information System (INIS)

    Tian Mingzhen; Barber, Zeb W.; Fischer, Joe A.; Randall Babbitt, Wm.

    2004-01-01

    We report the observation of the geometric phase in a closed two-level atomic system using stimulated photon echoes. The two-level system studied consists of the two-electronic energy levels ( 3 H 4 and 3 H 6 ) of Tm 3+ doped in YAG crystal. When a two-level atom at an arbitrary superposition state is excited by a pair of specially designed laser pulses, the excited state component gains a relative phase with respect to the ground state component. We identified the phase shift to be of pure geometric nature. The dynamic phase associated to the driving Hamiltonian is unchanged. The experiment results of the phase change agree with the theory to the extent of the measurement limit

  13. Phase structure rewrite systems in information retrieval

    Science.gov (United States)

    Klingbiel, P. H.

    1985-01-01

    Operational level automatic indexing requires an efficient means of normalizing natural language phrases. Subject switching requires an efficient means of translating one set of authorized terms to another. A phrase structure rewrite system called a Lexical Dictionary is explained that performs these functions. Background, operational use, other applications and ongoing research are explained.

  14. Integrated microwave photonics for phase modulated systems

    NARCIS (Netherlands)

    Marpaung, D.A.I.; Roeloffzen, C.G.H.

    2012-01-01

    For the last 25 years, microwave photonic (MWP) systems and links have relied almost exclusively on discrete optoelectronic devices, standard optical fibers and fiber-based components. With this concept, various functionalities like RF signal generation, distribution, processing and analysis have

  15. Phase Diagram of the Ethylene Glycol-Dimethylsulfoxide System

    Science.gov (United States)

    Solonina, I. A.; Rodnikova, M. N.; Kiselev, M. R.; Khoroshilov, A. V.; Shirokova, E. V.

    2018-05-01

    The phase diagram of ethylene glycol (EG)-dimethylsulfoxide (DMSO) system is studied in the temperature range of +25 to -140°C via differential scanning calorimetry. It is established that the EG-DMSO system is characterized by strong overcooling of the liquid phase, a glass transition at -125°C, and the formation of a compound with the composition of DMSO · 2EG. This composition has a melting temperature of -60°C, which is close to those of neighboring eutectics (-75 and -70°C). A drop in the baseline was observed in the temperature range of 8 to -5°C at DMSO concentrations of 5-50 mol %, indicating the existence of a phase separation area in the investigated system. The obtained data is compared to the literature data on the H2O-DMSO phase diagram.

  16. Inactive trials of transport systems: phase II

    International Nuclear Information System (INIS)

    Haberlin, M.M.; Hardy, A.R.; Kennedy, S.T.

    1986-11-01

    Progress made during 1984-85 is reviewed in four sections: the design and installation of a stainless steel working floor in the mock-up of a crate handling and size reduction facility; the detailed evaluation of a single air pad of the type used on commercial air-transporter; an experimental programme designed to examine the problems associated with the operation of a commercial air-transporter; the design, manufacture and commissioning trials of two powered conveyor units which when combined complete a remotely operated transfer system for transporting crated waste into and within the mock-up facility. (author)

  17. Microfabricated Gas Phase Chemical Analysis Systems

    International Nuclear Information System (INIS)

    FRYE-MASON, GREGORY CHARLES; HELLER, EDWIN J.; HIETALA, VINCENT M.; KOTTENSTETTE, RICHARD; LEWIS, PATRICK R.; MANGINELL, RONALD P.; MATZKE, CAROLYN M.; WONG, CHUNGNIN C.

    1999-01-01

    A portable, autonomous, hand-held chemical laboratory ((micro)ChemLab(trademark)) is being developed for trace detection (ppb) of chemical warfare (CW) agents and explosives in real-world environments containing high concentrations of interfering compounds. Microfabrication is utilized to provide miniature, low-power components that are characterized by rapid, sensitive and selective response. Sensitivity and selectivity are enhanced using two parallel analysis channels, each containing the sequential connection of a front-end sample collector/concentrator, a gas chromatographic (GC) separator, and a surface acoustic wave (SAW) detector. Component design and fabrication and system performance are described

  18. Phase 1 space fission propulsion system design considerations

    International Nuclear Information System (INIS)

    Houts, Mike; Van Dyke, Melissa; Godfroy, Tom; Pedersen, Kevin; Martin, James; Dickens, Ricky; Salvail, Pat; Hrbud, Ivana; Carter, Robert

    2002-01-01

    Fission technology can enable rapid, affordable access to any point in the solar system. If fission propulsion systems are to be developed to their full potential; however, near-term customers must be identified and initial fission systems successfully developed, launched, and operated. Studies conducted in fiscal year 2001 (IISTP, 2001) show that fission electric propulsion (FEP) systems operating at 80 kWe or above could enhance or enable numerous robotic outer solar system missions of interest. At these power levels it is possible to develop safe, affordable systems that meet mission performance requirements. In selecting the system design to pursue, seven evaluation criteria were identified: safety, reliability, testability, specific mass, cost, schedule, and programmatic risk. A top-level comparison of three potential concepts was performed: an SP-100 based pumped liquid lithium system, a direct gas cooled system, and a heatpipe cooled system. For power levels up to at least 500 kWt (enabling electric power levels of 125-175 kWe, given 25-35% power conversion efficiency) the heatpipe system has advantages related to several criteria and is competitive with respect to all. Hardware-based research and development has further increased confidence in the heatpipe approach. Successful development and utilization of a 'Phase 1' fission electric propulsion system will enable advanced Phase 2 and Phase 3 systems capable of providing rapid, affordable access to any point in the solar system

  19. Kilowatt isotope power system. Phase II plan. Volume I. Phase II program plan

    International Nuclear Information System (INIS)

    1978-01-01

    The development of a Kilowatt Isotope Power System (KIPS) was begun in 1975 for the purpose of satisfying the power requirements of satellites in the 1980's. The KIPS is a 238 PuO 2 -fueled organic Rankine cycle turbine power system to provide a design output of 500 to 2000 W. Phase II of the overall 3-phase KIPS program is described. This volume presents a program plan for qualifying the organic Rankine power system for flight test in 1982. The program plan calls for the design and fabrication of the proposed flight power system; conducting a development and a qualification program including both environmental and endurance testing, using an electrical and a radioisotope heat source; planning for flight test and spacecraft integration; and continuing ground demonstration system testing to act as a flight system breadboard and to accumulate life data

  20. Overview of Single-Phase Grid-Connected Photovoltaic Systems

    DEFF Research Database (Denmark)

    Yang, Yongheng; Blaabjerg, Frede

    2017-01-01

    A continuous booming installation of solar photovoltaic (PV) systems has been witnessed worldwide. It is mainly driven by the imperative demand of “clean” power generation from renewables. Grid-connected PV systems will thus become an even more active player in the future mixed power systems, which...... systems. This chapter thus gives an overview of the advancement of power electronics converters in single-phase grid-connected PV systems, being commonly used in residential applications. Demands to single-phase grid-connected PV systems and the general control strategies are also addressed...... are linked together by a vast of power electronics converters and the power grid. In order to achieve a reliable and efficient power generation from PV systems, more stringent demands have been imposed on the entire PV system. It, in return, advances the development of the power converter technology in PV...

  1. Organic Rankine Kilowatt Isotope Power System. Final phase I report

    International Nuclear Information System (INIS)

    1978-01-01

    On 1 August 1975 under Department of Energy Contract EN-77-C-02-4299, Sundstrand Energy Systems commenced development of a Kilowatt Isotope Power System (KIPS) directed toward satisfying the higher power requirements of satellites of the 1980s and beyond. The KIPS is a 238 PuO 2 fueled organic Rankine cycle turbine power system which will provide design output power in the range of 500 to 2000 W/sub (e)/ with a minimum of system changes. The principal objectives of the Phase 1 development effort were to: conceptually design a flight system; design a Ground Demonstration System (GDS) that is prototypic of the flight system in order to prove the feasibility of the flight system design; fabricate and assemble the GDS; and performance and endurance test the GDS using electric heaters in lieu of the isotope heat source. Results of the work performed under the Phase 1 contract to 1 July 1978 are presented

  2. Isotropic–Nematic Phase Transitions in Gravitational Systems

    Energy Technology Data Exchange (ETDEWEB)

    Roupas, Zacharias; Kocsis, Bence [Institute of Physics, Eötvös University, Pázmány P. s. 1/A, Budapest, 1117 (Hungary); Tremaine, Scott [Institute for Advanced Study, Princeton, NJ 08540 (United States)

    2017-06-20

    We examine dense self-gravitating stellar systems dominated by a central potential, such as nuclear star clusters hosting a central supermassive black hole. Different dynamical properties of these systems evolve on vastly different timescales. In particular, the orbital-plane orientations are typically driven into internal thermodynamic equilibrium by vector resonant relaxation before the orbital eccentricities or semimajor axes relax. We show that the statistical mechanics of such systems exhibit a striking resemblance to liquid crystals, with analogous ordered-nematic and disordered-isotropic phases. The ordered phase consists of bodies orbiting in a disk in both directions, with the disk thickness depending on temperature, while the disordered phase corresponds to a nearly isotropic distribution of the orbit normals. We show that below a critical value of the total angular momentum, the system undergoes a first-order phase transition between the ordered and disordered phases. At a critical point, the phase transition becomes second order, while for higher angular momenta there is a smooth crossover. We also find metastable equilibria containing two identical disks with mutual inclinations between 90° and 180°.

  3. Phase flow and statistical structure of Galton-board systems

    International Nuclear Information System (INIS)

    Lue, A.; Brenner, H.

    1993-01-01

    Galton boards, found in museum exhibits devoted to science and technology, are often used to demonstrate visually the ubiquity of so-called ''laws of probability'' via an experimental realization of normal distributions. A detailed theoretical study of Galton-board phase-space dynamics and statistical behavior is presented. The study is based on a simple inelastic-collision model employing a particle fall- ing through a spatially periodic lattice of rigid, convex scatterers. We show that such systems exhibit indeterminate behavior through the presence of strange attractors or strange repellers in phase space; nevertheless, we also show that these systems exhibit regular and predictable behavior under specific circumstances. Phase-space strange attractors, periodic attractors, and strange repellers are present in numerical simulations, confirming results anticipated from geometric analysis. The system's geometry (dictated by lattice geometry and density as well as the direction of gravity) is observed to play a dominant role in stability, phase-flow topology, and statistical observations. Smale horseshoes appear to exist in the low-lattice-density limit and may exist in other regimes. These horseshoes are generated by homoclinic orbits whose existence is dictated by system characteristics. The horseshoes lead directly to deterministic chaos in the system. Strong evidence exists for ergodicity in all attractors. Phase-space complexities are manifested at all observed levels, particularly statistical ones. Consequently, statistical observations are critically dependent upon system details. Under well-defined circumstances, these observations display behavior which does not constitute a realization of the ''laws of probability.''

  4. Two-phase systems. Fundamentals and industrial applications

    International Nuclear Information System (INIS)

    Woillez, Jacques

    2014-01-01

    Two-phase flows are omnipresent in industrial processes in different sectors with the behaviour and control of non-mixing mixtures of gas and liquids, of several liquids, of solids and fluids which are present in the production of raw materials, in the environment, in energy production, in chemistry, in pharmaceutical or food industry. The author presents the fundamentals elements which are needed to perform hardware predictive calculations and to understand typical phenomena associated with these flows. The chapters address fluids mechanics (movement equations, Bernoulli equation, load losses, turbulence, heat exchange coefficients, thermodynamics, compressible flows), two-phase systems (characteristic values, modes of appearance of two-phase flows, conduct flows, suspension mechanics, mass transfers, similarity, numerical simulation), the applications (energy production, agitation and mixing, phase separation, sprays), and peculiar phenomena (Marangoni effect, the tea cup effect, entry jets, water hammer effect, sound speed, two-phase pumping, fluidization)

  5. Preliminary investigation of liquid phase sintering in ferrous systems

    International Nuclear Information System (INIS)

    Klein, J.

    1975-04-01

    Liquid phase sintering was utilized to achieve, by a simple compaction and sintering procedure involving short times and moderate temperatures, a virtually full dense high carbon Fe:C alloy and high boron Fe:B alloy. Parameters such as powder characteristics and mixing, compacting pressure, heating program and the liquid phase fraction were found to influence the sintered density. The response of the Fe:C alloy to a heat treatment is reported along with preliminary experiments in the iron base ternary system Fe:W:C. Residual porosities observed in microstructures of certain liquid phase sintered compacts were accounted for by a proposed capillary flow of the liquid phase and a local densification competing against an overall densification. Some general recommendations are made for liquid phase sintering of powder aggregates. 15 fig., 7 tables

  6. A Novel Single Phase Hybrid Switched Reluctance Motor Drive System

    DEFF Research Database (Denmark)

    Liang, Jianing; Xu, Guoqing; Jian, Linni

    2011-01-01

    In this paper, a novel single phase hybrid switched reluctance motor(SRM) drive system is proposed. It integrated a single phase hybrid SRM and a novel single phase boost converter. This motor can reduce the number of phase switch. And the permanent magnet which is used in the motor can improve...... the performance and efficiency of SR motor. However, the inherent characteristic of this motor is that the negative torque is very sensitive with the excitation current near the turn-on angle. The slow excitation current limits the torque generation region and reduces the average torque. Therefore, a novel single...... phase boost converter is applied to improve the performance of this motor. It is easy to generate a double dclink voltage and dc-link voltage and switch both of them. The voltage of boost capacitor is self balance, so the protective circuit is not need to consider. The fast excitation mode helps hybrid...

  7. Phase equilibrium data for the ternary system (propane + chloroform + oryzanol)

    International Nuclear Information System (INIS)

    Correa, Fernanda V.; Comim, Sibele R.R.; Cesaro, Aline M. de; Rigo, Aline A.; Mazutti, Marcio A.; Hense, Haiko; Oliveira, J. Vladimir

    2011-01-01

    The compound oryzanol available in the rice bran (oriza sativa) is well known for its antioxidant activity. Phase equilibrium data involving oryzanol in compressed fluids, hardly found in the literature, are important to provide the basis for the extraction and fractionation processes. In this sense, the aim of this work is to report phase equilibrium measurements for the system (γ-oryzanol + chloroform) in compressed propane. Phase equilibrium experiments were performed using the static synthetic method (cloud points transition data) in a high-pressure variable-volume view cell in the temperature range of 303 K to 353 K, pressures up to 17 MPa, for oryzanol overall mass fractions of 2 wt%, 5 wt% and 10 wt% in (propane + chloroform) mixtures. A complex phase behaviour comprising vapour-liquid, liquid-liquid, vapour-liquid-liquid, solid-liquid, solid-liquid-liquid, solid-liquid-liquid-vapour transitions were visually observed for the system studied.

  8. Phase equilibrium data for the ternary system (propane + chloroform + oryzanol)

    Energy Technology Data Exchange (ETDEWEB)

    Correa, Fernanda V.; Comim, Sibele R.R. [EQA/UFSC, Chemical and Food Engineering Department, Federal University of Santa Catarina, C.P. 476, CEP 88040-900, Florianopolis, SC (Brazil); Cesaro, Aline M. de; Rigo, Aline A.; Mazutti, Marcio A. [Department of Food Engineering, URI - Campus de Erechim, Av. Sete de Setembro, 1621, 99700-000 Erechim, RS (Brazil); Hense, Haiko [EQA/UFSC, Chemical and Food Engineering Department, Federal University of Santa Catarina, C.P. 476, CEP 88040-900, Florianopolis, SC (Brazil); Oliveira, J. Vladimir, E-mail: vladimir@uricer.edu.b [Department of Food Engineering, URI - Campus de Erechim, Av. Sete de Setembro, 1621, 99700-000 Erechim, RS (Brazil)

    2011-01-15

    The compound oryzanol available in the rice bran (oriza sativa) is well known for its antioxidant activity. Phase equilibrium data involving oryzanol in compressed fluids, hardly found in the literature, are important to provide the basis for the extraction and fractionation processes. In this sense, the aim of this work is to report phase equilibrium measurements for the system ({gamma}-oryzanol + chloroform) in compressed propane. Phase equilibrium experiments were performed using the static synthetic method (cloud points transition data) in a high-pressure variable-volume view cell in the temperature range of 303 K to 353 K, pressures up to 17 MPa, for oryzanol overall mass fractions of 2 wt%, 5 wt% and 10 wt% in (propane + chloroform) mixtures. A complex phase behaviour comprising vapour-liquid, liquid-liquid, vapour-liquid-liquid, solid-liquid, solid-liquid-liquid, solid-liquid-liquid-vapour transitions were visually observed for the system studied.

  9. Interfacial properties and phase behaviour of an ionic microemulsion system

    NARCIS (Netherlands)

    Kegel, W.K.

    1993-01-01

    This thesis reports a study of a microemulsion model system composed of the ionic surfactant SDS (Sodium Dodecyl Sulfate), the cosurfactant pentanol and/or hexanol, water, salt and cyclohexane. Depending on the concentrations of the constituent parts, this system may form microemulsion phases and

  10. Controlling two-phase flow in microfluidic systems using electrowetting

    NARCIS (Netherlands)

    Gu, H.

    2011-01-01

    Electrowetting (EW)-based digital microfluidic systems (DMF) and droplet-based two-phase flow microfluidic systems (TPF) with closed channels are the most widely used microfluidic platforms. In general, these two approaches have been considered independently. However, integrating the two

  11. The minimization of ac phase noise in interferometric systems

    DEFF Research Database (Denmark)

    Filinski, Ignacy; Gordon, R A

    1994-01-01

    bladder vibration isolators are used incorrectly and do not provide sufficient reduction in the contribution of floor vibrations to phase noise. Several simple trampoline-type air bladder vibration isolator systems are described which are comparable in performance to commercial systems. With the exception...

  12. Induction accelerators for the phase rotator system

    International Nuclear Information System (INIS)

    Reginato, Lou; Yu, Simon; Vanecek, Dave

    2001-01-01

    The principle of magnetic induction has been applied to the acceleration of high current beams in betatrons and a variety of induction accelerators. The linear induction accelerator (LIA) consists of a simple nonresonant structure where the drive voltage is applied to an axially symmetric gap that encloses a toroidal ferromagnetic material. The change in flux in the magnetic core induces an axial electric field that provides particle acceleration. This simple nonresonant (low Q) structure acts as a single turn transformer that can accelerate from hundreds of amperes to tens of kiloamperes, basically only limited by the drive impedance. The LIA is typically a low gradient structure that can provide acceleration fields of varying shapes and time durations from tens of nanoseconds to several microseconds. The efficiency of the LIA depends on the beam current and can exceed 50% if the beam current exceeds the magnetization current required by the ferromagnetic material. The acceleration voltage available is simply given by the expression V=A dB/dt. Hence, for a given cross section of material, the beam pulse duration influences the energy gain. Furthermore, a premium is put on minimizing the diameter, which impacts the total weight or cost of the magnetic material. The diameter doubly impacts the cost of the LIA since the power (cost) to drive the cores is proportional to the volume as well. The waveform requirements during the beam pulse makes it necessary to make provisions in the pulsing system to maintain the desired dB/dt during the useful part of the acceleration cycle. This is typically done two ways, by using the final stage of the pulse forming network (PFN) and by the pulse compensation network usually in close proximity of the acceleration cell. The choice of magnetic materials will be made by testing various materials both ferromagnetic and ferrimagnetic. These materials will include the nickel-iron, silicon steel amorphous and various types of ferrites not

  13. Energy-dissipation-model for metallurgical multi-phase-systems

    Energy Technology Data Exchange (ETDEWEB)

    Mavrommatis, K.T. [Rheinisch-Westfaelische Technische Hochschule Aachen, Aachen (Germany)

    1996-12-31

    Entropy production in real processes is directly associated with the dissipation of energy. Both are potential measures for the proceed of irreversible processes taking place in metallurgical systems. Many of these processes in multi-phase-systems could then be modelled on the basis of the energy-dissipation associated with. As this entity can often be estimated using very simple assumptions from first principles, the evolution of an overall measure of systems behaviour can be studied constructing an energy-dissipation -based model of the system. In this work a formulation of this concept, the Energy-Dissipation-Model (EDM), for metallurgical multi-phase-systems is given. Special examples are studied to illustrate the concept, and benefits as well as the range of validity are shown. This concept might be understood as complement to usual CFD-modelling of complex systems on a more abstract level but reproducing essential attributes of complex metallurgical systems. (author)

  14. Energy-dissipation-model for metallurgical multi-phase-systems

    Energy Technology Data Exchange (ETDEWEB)

    Mavrommatis, K T [Rheinisch-Westfaelische Technische Hochschule Aachen, Aachen (Germany)

    1997-12-31

    Entropy production in real processes is directly associated with the dissipation of energy. Both are potential measures for the proceed of irreversible processes taking place in metallurgical systems. Many of these processes in multi-phase-systems could then be modelled on the basis of the energy-dissipation associated with. As this entity can often be estimated using very simple assumptions from first principles, the evolution of an overall measure of systems behaviour can be studied constructing an energy-dissipation -based model of the system. In this work a formulation of this concept, the Energy-Dissipation-Model (EDM), for metallurgical multi-phase-systems is given. Special examples are studied to illustrate the concept, and benefits as well as the range of validity are shown. This concept might be understood as complement to usual CFD-modelling of complex systems on a more abstract level but reproducing essential attributes of complex metallurgical systems. (author)

  15. Adaptive nonlinear control of single-phase to three-phase UPS system

    Directory of Open Access Journals (Sweden)

    Kissaoui M.

    2014-01-01

    Full Text Available This work deals with the problems of uninterruptible power supplies (UPS based on the single-phase to three-phase converters built in two stages: an input bridge rectifier and an output three phase inverter. The two blocks are joined by a continuous intermediate bus. The objective of control is threefold: i power factor correction “PFC”, ii generating a symmetrical three-phase system at the output even if the load is unknown, iii regulating the DC bus voltage. The synthesis of controllers has been reached by two nonlinear techniques that are the sliding mode and adaptive backstepping control. The performances of regulators have been validated by numerical simulation in MATLAB / SIMULINK.

  16. Phase Analysis of the Cellulose Triacetate-Nitromethane System

    Directory of Open Access Journals (Sweden)

    Anna B. Shipovskaya

    2012-01-01

    Full Text Available A comprehensive study was made on the cellulose triacetate-nitromethane system to explore its phase separation within ranges 2–25 wt.% and −5÷+80°C by means of polarization light and electron microscopy, the turbidity spectrum method, differential thermal and X-ray analyses, and rheological techniques. The physical state of the polymer was identified within the phase coexistence boundaries on the phase diagram which included three types of phase separation (amorphous (with a UCST at Tcr=57∘C and ccr=7.3 wt.%, crystal, and liquid crystal. The boundaries of the regions determining the coexistence of the liquid crystal (LC and the partly crystal phase were found to be inside the region of amorphous liquid-liquid phase separation. For cellulose ester-solvent systems, this state diagram is the first experimental evidence for the possibility of coexistence of several phases with amorphous, LC, and crystal polymer ordering.

  17. Phase synchronization of multiple klystrons in RF system

    International Nuclear Information System (INIS)

    Kwon, S.; Regan, A.; Wang, Y.M.; Rohlev, T.

    1998-01-01

    The Low Energy Demonstration Accelerator (LEDA) being constructed at Los Alamos National Laboratory will serve as the prototype for the low energy section of the Acceleration Production of Tritium (APT) accelerator. The first LEDA RF system includes three, 1.2 MW, 350 MHz, continuous wave, klystrons driving a radio frequency quadrupole (RFQ). A phase control loop is necessary for each individual klystron in order to guarantee the phase matching of these klystrons. To meet this objective, they propose adaptive PI controllers which are based on simple adaptive control. These controllers guarantee not only phase matching but also amplitude matching

  18. Modeling and design of reacting systems with phase transfer catalysis

    DEFF Research Database (Denmark)

    Piccolo, Chiara; Hodges, George; Piccione, Patrick M.

    2011-01-01

    Issues related to the design of biphasic (liquid) catalytic reaction operations are discussed. A chemical system involving the reaction of an organic-phase soluble reactant (A) with an aqueous-phase soluble reactant (B) in the presence of phase transfer catalyst (PTC) is modeled and based on it......, some of the design issues related to improved reaction operation are analyzed. Since the solubility of the different forms of the PTC in the organic solvent affects ultimately the catalyst partition coefficients, therefore, the organic solvent plays an important role in the design of PTC-based reacting...

  19. Phase equilibria in Ca–Co–O system

    Czech Academy of Sciences Publication Activity Database

    Sedmidubský, D.; Jakeš, V.; Jankovský, O.; Leitner, J.; Šofer, Z.; Hejtmánek, Jiří

    2012-01-01

    Roč. 194, OCT (2012), s. 199-205 ISSN 0022-4596 R&D Projects: GA ČR GA203/09/1036 Institutional research plan: CEZ:AV0Z10100521 Keywords : Ca–Co–O system , Misfit cobaltites, Thermodynamic data, Phase diagrams * misfit cobaltites * thermodynamic data * phase diagrams Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.040, year: 2012

  20. Phase equilibrium study on system uranium-plutonium-tungsten-carbon

    International Nuclear Information System (INIS)

    Ugajin, Mitsuhiro

    1976-11-01

    Metallurgical properties of the U-Pu-W-C system have been studied with emphasis on phases and reactions. Free energy of compound formation, carbon activity and U/Pu segregation in the W-doped carbide fuel are estimated using phase diagram data. The results indicate that tungsten metal is useful as a thermochemical stabilizer of the carbide fuel. Tungsten has high temperature stability in contact with uranium carbide and mixed uranium-plutonium carbide. (auth.)

  1. Modelling of Phase Equlibria in the Hf-V System\

    Czech Academy of Sciences Publication Activity Database

    Vřešťál, Jan; Pavlů, Jana; Wdowik, U. D.; Šob, Mojmír

    2017-01-01

    Roč. 53, č. 3 (2017), s. 239-247 ISSN 1450-5339 R&D Projects: GA ČR GA14-15576S; GA MŠk(CZ) LQ1601 Institutional support: RVO:68081723 Keywords : Laves phases * Hf-V system * Ab initio calculations * Phase diagram * Zero Kelvin * CALPHAD method Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 0.804, year: 2016

  2. Phase Noise Comparision of Short Pulse Laser Systems

    Energy Technology Data Exchange (ETDEWEB)

    S. Zhang; S. V. Benson; J. Hansknecht; D. Hardy; G. Neil; Michelle D. Shinn

    2006-12-01

    This paper describes the phase noise measurement on several different mode-locked laser systems that have completely different gain media and configurations including a multi-kW free-electron laser. We will focus on the state of the art short pulse lasers, especially the drive lasers for photocathode injectors. A comparison between the phase noise of the drive laser pulses, electron bunches and FEL pulses will also be presented.

  3. PHASE NOISE COMPARISON OF SHORT PULSE LASER SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Shukui Zhang; Stephen Benson; John Hansknecht; David Hardy; George Neil; Michelle D. Shinn

    2006-08-27

    This paper describes phase noise measurements of several different laser systems that have completely different gain media and configurations including a multi-kW free-electron laser. We will focus on state-of-the-art short pulse lasers, especially drive lasers for photocathode injectors. Phase noise comparison of the FEL drive laser, electron beam and FEL laser output also will be presented.

  4. Excitation power quantities in phase resonance testing of nonlinear systems with phase-locked-loop excitation

    Science.gov (United States)

    Peter, Simon; Leine, Remco I.

    2017-11-01

    Phase resonance testing is one method for the experimental extraction of nonlinear normal modes. This paper proposes a novel method for nonlinear phase resonance testing. Firstly, the issue of appropriate excitation is approached on the basis of excitation power considerations. Therefore, power quantities known from nonlinear systems theory in electrical engineering are transferred to nonlinear structural dynamics applications. A new power-based nonlinear mode indicator function is derived, which is generally applicable, reliable and easy to implement in experiments. Secondly, the tuning of the excitation phase is automated by the use of a Phase-Locked-Loop controller. This method provides a very user-friendly and fast way for obtaining the backbone curve. Furthermore, the method allows to exploit specific advantages of phase control such as the robustness for lightly damped systems and the stabilization of unstable branches of the frequency response. The reduced tuning time for the excitation makes the commonly used free-decay measurements for the extraction of backbone curves unnecessary. Instead, steady-state measurements for every point of the curve are obtained. In conjunction with the new mode indicator function, the correlation of every measured point with the associated nonlinear normal mode of the underlying conservative system can be evaluated. Moreover, it is shown that the analysis of the excitation power helps to locate sources of inaccuracies in the force appropriation process. The method is illustrated by a numerical example and its functionality in experiments is demonstrated on a benchmark beam structure.

  5. Competing failure analysis in phased-mission systems with functional dependence in one of phases

    International Nuclear Information System (INIS)

    Wang, Chaonan; Xing, Liudong; Levitin, Gregory

    2012-01-01

    This paper proposes an algorithm for the reliability analysis of non-repairable phased-mission systems (PMS) subject to competing failure propagation and isolation effects. A failure originating from a system component which causes extensive damage to other system components is a propagated failure. When the propagated failure affects all the system components, causing the entire system failure, a propagated failure with global effect (PFGE) is said to occur. However, the failure propagation can be isolated in systems subject to functional dependence (FDEP) behavior, where the failure of a component (referred to as trigger component) causes some other components (referred to as dependent components) to become inaccessible or unusable (isolated from the system), and thus further failures from these dependent components have no effect on the system failure behavior. On the other hand, if any PFGE from dependent components occurs before the trigger failure, the failure propagation effect takes place, causing the overall system failure. In summary, there are two distinct consequences of a PFGE due to the competition between the failure isolation and failure propagation effects in the time domain. Existing works on such competing failures focus only on single-phase systems. However, many real-world systems are phased-mission systems (PMS), which involve multiple, consecutive and non-overlapping phases of operations or tasks. Consideration of competing failures for PMS is a challenging and difficult task because PMS exhibit dynamics in the system configuration and component behavior as well as statistical dependencies across phases for a given component. This paper proposes a combinatorial method to address the competing failure effects in the reliability analysis of binary non-repairable PMS. The proposed method is verified using a Markov-based method through a numerical example. Different from the Markov-based approach that is limited to exponential distribution, the

  6. Integrated monitoring and surveillance system demonstration project: Phase I accomplishments

    International Nuclear Information System (INIS)

    Aumeier, S.E.; Walters, B.G.; Crawford, D.C.

    1997-01-01

    The authors present the results of the Integrated Monitoring and Surveillance System (IMSS) demonstration project Phase I efforts. The rationale behind IMSS development is reviewed and progress in each of the 5 basic tasks is detailed. Significant results include decisions to use Echelon LonWorks networking protocol and Microsoft Access for the data system needs, a preliminary design for the plutonium canning system glovebox, identification of facilities and materials available for the demonstration, determination of possibly affected facility documentation, and a preliminary list of available sensor technologies. Recently imposed changes in the overall project schedule and scope are also discussed and budgetary requirements for competition of Phase II presented. The results show that the IMSS demonstration project team has met and in many cases exceeded the commitments made for Phase I deliverables

  7. Two-phase flow induced parametric vibrations in structural systems

    International Nuclear Information System (INIS)

    Hara, Fumio

    1980-01-01

    This paper is divided into two parts concerning piping systems and a nuclear fuel pin system. The significant experimental results concerning the random vibration induced in an L-shaped pipe by air-water two-phase flow and the theoretical analysis of the vibration are described in the first part. It was clarified for the first time that the parametric excitation due to the periodic changes of system mass, centrifugal force and Coriolis force was the mechanism of exciting the vibration. Moreover, the experimental and theoretical analyses of the mechanism of exciting vibration by air-water two-phase flow in a straight, horizontal pipe were carried out, and the first natural frequency of the piping system was strongly related to the dominant frequency of void signals. The experimental results on the vibration of a nuclear fuel pin model in parallel air-water two-phase flow are reported in the latter part. The relations between vibrational strain variance and two-phase flow velocity or pressure fluctuation, and the frequency characteristics of vibrational strain variance were obtained. The theoretical analysis of the dynamic interaction between air-water two-phase flow and a fuel pin structure, and the vibrational instability of fuel pins in alternate air and water slugs or in large bubble flow are also reported. (Kako, I.)

  8. Phase diagram of a modified Lennard-Jones system

    International Nuclear Information System (INIS)

    Sakagami, Takahiro; Fuchizaki, Kazuhiro

    2010-01-01

    The well-known Lennard-Jones potential is modified in such a way that it smoothly vanishes at a certain distance. A system whose interparticle interaction is given by such a potential is referred to as a modified Lennard-Jones system, and is served as a standard system describing simple solids and fluids. A phase diagram is determined based on the free energies obtained through thermodynamic integration.

  9. Phase transition temperatures of Sn-Zn-Al system and their comparison with calculated phase diagrams

    Czech Academy of Sciences Publication Activity Database

    Smetana, B.; Zlá, S.; Kroupa, Aleš; Žaludová, M.; Drápala, J.; Burkovič, R.; Petlák, D.

    2012-01-01

    Roč. 110, č. 1 (2012), s. 369-378 ISSN 1388-6150 R&D Projects: GA MŠk(CZ) OC08053 Institutional support: RVO:68081723 Keywords : Sn-Zn-Al system * DTA * phase transition temperatures Subject RIV: BJ - Thermodynamics Impact factor: 1.982, year: 2012

  10. Phase equilibria of the Mo-Al-Ho ternary system

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yitai; Chen, Xiaoxian; Liu, Hao [Guangxi Univ., Nanning (China). College of Materials Science and Engineering; Guangxi Univ., Nanning (China). Guangxi Key Laboratory of Processing for Non-ferrous Metal and Featured Materials; Zhan, Yongzhong [Guangxi Univ., Nanning (China). College of Materials Science and Engineering; Guangxi Univ., Nanning (China). Guangxi Key Laboratory of Processing for Non-ferrous Metal and Featured Materials; Guangxi Univ., Nanning (China). Center of Ecological Collaborative Innovation for Aluminum Industry

    2017-08-15

    Investigation into the reactions and phase equilibria of transition metal elements (i.e. Mo, Zr, Cr, V and Ti), Al and rare earths is academically and industrially important for the development of both refractory alloys and lightweight high-temperature materials. In this work, the equilibria of the Mo-Al-Ho ternary system at 773 K have been determined by using X-ray powder diffraction and scanning electron microscopy equipped with energy dispersive X-ray analysis. A new ternary phase Al{sub 4}Mo{sub 2}Ho has been found and the other ternary phase Al{sub 43}Mo{sub 4}Ho{sub 6} is observed. Ten binary phases in the Al-Mo and Al-Ho systems, including Al{sub 17}Mo{sub 4} rather than Al{sub 4}Mo, have been determined to exist at 773 K. The homogeneity ranges of AlMo{sub 3} and Al{sub 8}Mo{sub 3} phase are 7.5 at.% and 1 at.%, respectively. According to the phase-disappearing method, the maximum solubility of Al in Mo is about 16 at.%.

  11. Phase ambiguity resolution for offset QPSK modulation systems

    Science.gov (United States)

    Nguyen, Tien M. (Inventor)

    1991-01-01

    A demodulator for Offset Quaternary Phase Shift Keyed (OQPSK) signals modulated with two words resolves eight possible combinations of phase ambiguity which may produce data error by first processing received I(sub R) and Q(sub R) data in an integrated carrier loop/symbol synchronizer using a digital Costas loop with matched filters for correcting four of eight possible phase lock errors, and then the remaining four using a phase ambiguity resolver which detects the words to not only reverse the received I(sub R) and Q(sub R) data channels, but to also invert (complement) the I(sub R) and/or Q(sub R) data, or to at least complement the I(sub R) and Q(sub R) data for systems using nontransparent codes that do not have rotation direction ambiguity.

  12. Tube Radial Distribution Flow Separation in a Microchannel Using an Ionic Liquid Aqueous Two-Phase System Based on Phase Separation Multi-Phase Flow.

    Science.gov (United States)

    Nagatani, Kosuke; Shihata, Yoshinori; Matsushita, Takahiro; Tsukagoshi, Kazuhiko

    2016-01-01

    Ionic liquid aqueous two-phase systems were delivered into a capillary tube to achieve tube radial distribution flow (TRDF) or annular flow in a microspace. The phase diagram, viscosity of the phases, and TRDF image of the 1-butyl-3-methylimidazolium chloride and NaOH system were examined. The TRDF was formed with inner ionic liquid-rich and outer ionic liquid-poor phases in the capillary tube. The phase configuration was explained using the viscous dissipation principle. We also examined the distribution of rhodamine B in a three-branched microchannel on a microchip with ionic liquid aqueous two-phase systems for the first time.

  13. Quantum Phase Transitions in Conventional Matrix Product Systems

    Science.gov (United States)

    Zhu, Jing-Min; Huang, Fei; Chang, Yan

    2017-02-01

    For matrix product states(MPSs) of one-dimensional spin-1/2 chains, we investigate a new kind of conventional quantum phase transition(QPT). We find that the system has two different ferromagnetic phases; on the line of the two ferromagnetic phases coexisting equally, the system in the thermodynamic limit is in an isolated mediate-coupling state described by a paramagnetic state and is in the same state as the renormalization group fixed point state, the expectation values of the physical quantities are discontinuous, and any two spin blocks of the system have the same geometry quantum discord(GQD) within the range of open interval (0,0.25) and the same classical correlation(CC) within the range of open interval (0,0.75) compared to any phase having no any kind of correlation. We not only realize the control of QPTs but also realize the control of quantum correlation of quantum many-body systems on the critical line by adjusting the environment parameters, which may have potential application in quantum information fields and is helpful to comprehensively and deeply understand the quantum correlation, and the organization and structure of quantum correlation especially for long-range quantum correlation of quantum many-body systems.

  14. Large resistivity modulation in mixed-phase metallic systems.

    Science.gov (United States)

    Lee, Yeonbae; Liu, Z Q; Heron, J T; Clarkson, J D; Hong, J; Ko, C; Biegalski, M D; Aschauer, U; Hsu, S L; Nowakowski, M E; Wu, J; Christen, H M; Salahuddin, S; Bokor, J B; Spaldin, N A; Schlom, D G; Ramesh, R

    2015-01-07

    In numerous systems, giant physical responses have been discovered when two phases coexist; for example, near a phase transition. An intermetallic FeRh system undergoes a first-order antiferromagnetic to ferromagnetic transition above room temperature and shows two-phase coexistence near the transition. Here we have investigated the effect of an electric field to FeRh/PMN-PT heterostructures and report 8% change in the electrical resistivity of FeRh films. Such a 'giant' electroresistance (GER) response is striking in metallic systems, in which external electric fields are screened, and thus only weakly influence the carrier concentrations and mobilities. We show that our FeRh films comprise coexisting ferromagnetic and antiferromagnetic phases with different resistivities and the origin of the GER effect is the strain-mediated change in their relative proportions. The observed behaviour is reminiscent of colossal magnetoresistance in perovskite manganites and illustrates the role of mixed-phase coexistence in achieving large changes in physical properties with low-energy external perturbation.

  15. The potential of cloud point system as a novel two-phase partitioning system for biotransformation.

    Science.gov (United States)

    Wang, Zhilong

    2007-05-01

    Although the extractive biotransformation in two-phase partitioning systems have been studied extensively, such as the water-organic solvent two-phase system, the aqueous two-phase system, the reverse micelle system, and the room temperature ionic liquid, etc., this has not yet resulted in a widespread industrial application. Based on the discussion of the main obstacles, an exploitation of a cloud point system, which has already been applied in a separation field known as a cloud point extraction, as a novel two-phase partitioning system for biotransformation, is reviewed by analysis of some topical examples. At the end of the review, the process control and downstream processing in the application of the novel two-phase partitioning system for biotransformation are also briefly discussed.

  16. HPT Clearance Control: Intelligent Engine Systems-Phase 1

    Science.gov (United States)

    2005-01-01

    The following work has been completed to satisfy the Phase I Deliverables for the "HPT Clearance Control" project under NASA GRC's "Intelligent Engine Systems" program: (1) Need for the development of an advanced HPT ACC system has been very clearly laid out, (2) Several existing and potential clearance control systems have been reviewed, (3) A scorecard has been developed to document the system, performance (fuel burn, range, payload, etc.), thermal, and mechanical characteristics of the existing clearance control systems, (4) Engine size and flight cycle selection for the advanced HPT ACC system has been reviewed with "large engine"/"long range mission" combination showing the most benefit, (5) A scoring criteria has been developed to tie together performance parameters for an objective, data driven comparison of competing systems, and (6) The existing HPT ACC systems have been scored based on this scoring system.

  17. Phase transformations and systems driven far from equilibrium

    International Nuclear Information System (INIS)

    Ma, E.; Atzmon, M.; Bellon, P.; Trivedi, R.

    1998-01-01

    This volume compiles invited and contributed papers that were presented at Symposium B of the 1997 Materials Research Society Fall Meeting, Phase Transformations and Systems Driven Far From Equilibrium, which was held December 1--5, in Boston, Massachusetts. While this symposium followed the tradition of previous MRS symposia on the fundamental topic of phase transformations, this year the emphasis was on materials systems driven far from equilibrium. The central theme of the majority of the work presented is the understanding of the thermodynamics and kinetics of phase transformations, with significant coverage of metastable materials and externally forced transformations driven, for example, by energy beams or mechanical deformation. The papers are arranged in seven sections: solidification theory and experiments; nucleation; solid state transformations and microstructural evolution; beam-induced transformations; amorphous solids; interfacial and thin film transformations; and nanophases and mechanical alloying. One hundred three papers have been processed separately for inclusion on the data base

  18. Standing phase angle reduction for power system restoration

    Energy Technology Data Exchange (ETDEWEB)

    Hazarika, D. [Assam Engineering College (India). Electrical Engineering Dept.; Sinha, A.K. [IIT Khargpur (India). Electrical Engineering Dept.

    1998-01-01

    The paper describes a methodology for the reduction of standing phase angle (SPA) difference between two buses of a power system, which is essential before interconnecting a line between two buses. This problem is encountered normally during restoration operations of a power system. For this purpose, the standing phase angle difference between two specific buses is represented in terms of sensitivity factors associated with the change in real power injections at the buses. To arrive at the desired standing phase angle difference between two buses, the modified contribution at generation/load buses have been evaluated based on 'higher the sensitivity higher the participation' logic. This methodology acts as a direct help to reduce excessive SPA difference between two buses to an acceptable limit, which otherwise requires regulation of various generation levels on a trial and error basis. (author)

  19. Geometric phase for N-level systems through unitary integration

    International Nuclear Information System (INIS)

    Uskov, D. B.; Rau, A. R. P.

    2006-01-01

    Geometric phases are important in quantum physics and are now central to fault-tolerant quantum computation. For spin 1/2, the Bloch sphere S 2 , together with a U(1) phase, provides a complete SU(2) description. We generalize to N-level systems and SU(N) in terms of a 2(N-1)-dimensional base space and reduction to a (N-1)-level problem, paralleling closely the two-dimensional case. This iteratively solves the time evolution of an N-level system and gives (N-1) geometric phases explicitly. A complete analytical construction of an S 4 Bloch-like sphere for two qubits is given for the Spin(5) or SO(5) subgroup of SU(4)

  20. Space reactor electric systems: system integration studies, Phase 1 report

    International Nuclear Information System (INIS)

    Anderson, R.V.; Bost, D.; Determan, W.R.; Harty, R.B.; Katz, B.; Keshishian, V.; Lillie, A.F.; Thomson, W.B.

    1983-01-01

    This report presents the results of preliminary space reactor electric system integration studies performed by Rockwell International's Energy Systems Group (ESG). The preliminary studies investigated a broad range of reactor electric system concepts for powers of 25 and 100 KWe. The purpose of the studies was to provide timely system information of suitable accuracy to support ongoing mission planning activities. The preliminary system studies were performed by assembling the five different subsystems that are used in a system: the reactor, the shielding, the primary heat transport, the power conversion-processing, and the heat rejection subsystems. The subsystem data in this report were largely based on Rockwell's recently prepared Subsystem Technology Assessment Report. Nine generic types of reactor subsystems were used in these system studies. Several levels of technology were used for each type of reactor subsystem. Seven generic types of power conversion-processing subsystems were used, and several levels of technology were again used for each type. In addition, various types and levels of technology were used for the shielding, primary heat transport, and heat rejection subsystems. A total of 60 systems were studied

  1. A Transformer-less Single Phase Inverter For photovoltaic Systems

    DEFF Research Database (Denmark)

    Mostaan, Ali; Alizadeh, Ebrahim; Qu, Ying

    2017-01-01

    A single phase transformer-less inverter is introduced in this paper. The negative polarities of the input voltage and output terminal have common ground. Therefore, the leakage current problem that is common in PV systems is eliminated naturally. In addition, the proposed inverter has fewer comp...

  2. On the classical limit of Berry's phase integrable systems

    International Nuclear Information System (INIS)

    Asch, J.

    1990-01-01

    Berry's Phase is given by integration of a characteristic two form. We consider integrable systems defined by Weyl quantized classical Hamiltonians. It is shown that the limit of ℎ/i times this two form is the curvature of the classical connection whose holonomy are the Hannay angles. A result of this type was derived by Berry [B2]. (orig.)

  3. Phase analysis of Fe-B-V system

    Czech Academy of Sciences Publication Activity Database

    Homolová, V.; Výrostková, A.; Čiripová, L.; Kroupa, Aleš

    2013-01-01

    Roč. 51, č. 2 (2013), s. 135-139 ISSN 0023-432X R&D Projects: GA ČR(CZ) GAP108/10/1908 Institutional support: RVO:68081723 Keywords : CALPHAD method * Fe-B-V system * phase diagram Subject RIV: BJ - Thermodynamics Impact factor: 0.546, year: 2013

  4. Predicting phase equilibria in one-component systems

    Science.gov (United States)

    Korchuganova, M. R.; Esina, Z. N.

    2015-07-01

    It is shown that Simon equation coefficients for n-alkanes and n-alcohols can be modeled using critical and triple point parameters. Predictions of the phase liquid-vapor, solid-vapor, and liquid-solid equilibria in one-component systems are based on the Clausius-Clapeyron relation, Van der Waals and Simon equations, and the principle of thermodynamic similarity.

  5. Phase Change Permeation Technology For Environmental Control Life Support Systems

    Science.gov (United States)

    Wheeler, Raymond M.

    2014-01-01

    Use of a phase change permeation membrane (Dutyion [Trademark]) to passively and selectively mobilize water in microgravity to enable improved water recovery from urine/brine for Environment Control and Life Support Systems (ECLSS) and water delivery to plans for potential use in microgravity.

  6. A nonlocal phase-field system with inertial term

    Czech Academy of Sciences Publication Activity Database

    Grasselli, M.; Petzeltová, Hana; Schimperna, G.

    2007-01-01

    Roč. 65, č. 3 (2007), s. 451-469 ISSN 0033-569X R&D Projects: GA AV ČR(CZ) IAA100190606 Institutional research plan: CEZ:AV0Z10190503 Keywords : nonlocal phase-field system * Lojasiewicz inequality * convergence to equilibria Subject RIV: BA - General Mathematics Impact factor: 0.463, year: 2007

  7. Wet Process Induced Phase Transited Drug Delivery System as a ...

    African Journals Online (AJOL)

    A non-disintegrating, asymmetric membrane capsular system for a poorly water soluble drug, flurbiprofen, was developed and evaluated in vitro and in vivo. Asymmetric membrane capsules were made by phase inversion. The effect of varying osmotic pressure of the dissolution medium on drug release was studied.

  8. An expert system as applied to bridges : software development phase.

    Science.gov (United States)

    1989-01-01

    This report describes the results of the third of a four-part study dealing with the use of a computerized expert system to assist bridge engineers in their structures management program. In this phase of the study, software (called DOBES) was writte...

  9. A proposed phase equilibrium diagram for Pt-Zr system

    International Nuclear Information System (INIS)

    Arias, D.E.; Gribaudo, L.

    1993-01-01

    A revision of the phase diagram of the Pt-Zr system is presented using up to date information from recent publications. The proposed change concerning the invariant transformation in the Pt-rich zone is supported by simplified thermodynamic evaluations. (author). 12 refs., 1 fig

  10. A single phase photovoltaic inverter control for grid connected system

    Indian Academy of Sciences (India)

    This paper presents a control scheme for single phase grid connected photovoltaic (PV) system operating under both grid connected and isolated grid mode. The control techniques include voltage and current control of grid-tie PV inverter. During grid connected mode, grid controls the amplitude and frequency of the PV ...

  11. Phase transitions in spin systems with modulated order

    International Nuclear Information System (INIS)

    Coutinho Filho, M.D.

    1984-01-01

    Spin systems which may display modulated structures are treated. A layered Ising model with competing interactions between nearest and next-nearest layers in the presence of a magnetic field is studied. In the context of a mean-field approximation, the high-temperature region of the phase diagram is studied analytically. The Λ surface, separating the paramagnetic and the modulated phases, is bounded by two lines of tricritical points which join smoothly at the Lifshitz point and terminate at multicritical points, beyond which lines of critical and double critical end points are expected to appear. The low-temperature region is studied numerically. T-H phase diagrams, which exhibit a variety of modulated phases, for various values of the ratio of the strength of the competing interactions are constructed. A theoretical interpretation for the occurrence of a Lifshitz point in the field-temperature phase diagram of MnP is presented. These results, which are based on a X-Y localized spin Hamiltonian, are in qualitative agreement with recently reported experiments. In particular, asymptotic expressions are obtained for the phase boundaries, which meet tangentially at the Lifshitz point, and for some other thermodynamic quantities of interest, such as the longitudinal and transverse susceptibilities. (Author) [pt

  12. Prototyping of CBRN threat assessment system. Phase 1

    International Nuclear Information System (INIS)

    Ina, Shinichiro; Suzuki, Tomoyuki; Maeno, Akihiro; Sakaue, Motoki

    2015-01-01

    Recently, chemical, biological, radiological and nuclear threats, that is, CBRN threats have emerged. In order to support the Japan Self Defense Forces unit coping with the CBRN threats, it is important to take measures against these invisible threats. Our CBRN threat assessment system will make invisible CBRN threats visible. This report describes a prototyping of the CBRN threat assessment system (PHASE 1) carried out from fiscal year 2012-2014. (author)

  13. Peptide-tagged proteins in aqueous two-phase systems

    OpenAIRE

    Nilsson, Anna

    2002-01-01

    This thesis deals with proteins containing peptide tags for improved partitioning in aqueous two-phase systems. Qualitatively the peptide-tagged protein partitioning could be predicted from peptide data, i.e. partitioning trends found for peptides were also found for the peptide-tagged proteins. However, full effect of the tag as expected from peptide partitioning was not found in the tagged protein. When alkyl-ethylene oxide surfactant was included in a two-polymer system, almost full effect...

  14. Mixing phases of unstable two-level systems

    International Nuclear Information System (INIS)

    Sokolov, V.V.; Brentano, P. von.

    1993-01-01

    An unstable two-level system decaying into an arbitrary number of channels is considered. It is shown that the mixing phases of the two overlapping resonances can be expressed in the terms of their partial widths and one additional universal mixing parameter. Some applications to a doublet of 2 + resonances in 8 Be and to the ρ-ω systems are considered. 18 refs

  15. Automated phased array ultrasonic inspection system for rail wheel sets

    International Nuclear Information System (INIS)

    Grosser, Paul; Weiland, M.G.

    2013-01-01

    This paper covers the design, system automation, calibration and validation of an automated ultrasonic system for the inspection of new and in service wheel set assemblies from diesel-electric locomotives and gondola cars. This system uses Phased Array (PA) transducers for flaw detection and Electro-Magnetic Acoustic Transducers (EMAT) for the measurement of residual stress. The system collects, analyses, evaluates and categorizes the wheel sets automatically. This data is archived for future comparison and trending. It is also available for export to a portal lathe for increased efficiency and accuracy of machining, therefore allowing prolonged wheel life.

  16. Code-modulated interferometric imaging system using phased arrays

    Science.gov (United States)

    Chauhan, Vikas; Greene, Kevin; Floyd, Brian

    2016-05-01

    Millimeter-wave (mm-wave) imaging provides compelling capabilities for security screening, navigation, and bio- medical applications. Traditional scanned or focal-plane mm-wave imagers are bulky and costly. In contrast, phased-array hardware developed for mass-market wireless communications and automotive radar promise to be extremely low cost. In this work, we present techniques which can allow low-cost phased-array receivers to be reconfigured or re-purposed as interferometric imagers, removing the need for custom hardware and thereby reducing cost. Since traditional phased arrays power combine incoming signals prior to digitization, orthogonal code-modulation is applied to each incoming signal using phase shifters within each front-end and two-bit codes. These code-modulated signals can then be combined and processed coherently through a shared hardware path. Once digitized, visibility functions can be recovered through squaring and code-demultiplexing operations. Pro- vided that codes are selected such that the product of two orthogonal codes is a third unique and orthogonal code, it is possible to demultiplex complex visibility functions directly. As such, the proposed system modulates incoming signals but demodulates desired correlations. In this work, we present the operation of the system, a validation of its operation using behavioral models of a traditional phased array, and a benchmarking of the code-modulated interferometer against traditional interferometer and focal-plane arrays.

  17. Phase equilibria, phases and compounds in the Ti-C system

    International Nuclear Information System (INIS)

    Gusev, Aleksandr I

    2002-01-01

    The results of experimental and theoretical investigations of the phase equilibria in the titanium-carbon system are generalised. The generalised thermodynamic characteristics of disordered titanium carbide TiC y , are reported. Peculiarities of the crystal structures of all the known and hypothetical compounds of titanium with carbon are considered in detail. The X-ray diffraction patterns which allow identification of all these compounds are presented. The phase diagrams of the Ti-C system constructed with allowance for atomic ordering of non-stoichio metric carbide, TiC y , and for the existence of the molecular cluster-like compounds Ti 8 C 12 and Ti 13 C 22 (TiC 2 ) are discussed. The bibliography includes 142 references.

  18. Phase equilibria, phases and compounds in the Ti-C system

    International Nuclear Information System (INIS)

    Gusev, A.I.

    2002-01-01

    The results of experimental and theoretical investigations related to the phase equilibria in the titanium-carbon system are generalized. The generalized thermodynamic characteristics of the disordered titanium carbide TiC y are given. The crystal structure of all the discovered and hypothetical compounds of titanium with carbon are considered in detail. The x-ray diffraction patterns which allow one to identify all these compounds are given. The phase diagrams of the Ti-C system constructed with allowance for atomic ordering of non-stoichiometric TiC y carbide and for the existence of the compounds Ti 8 C 12 and Ti 13 C 22 (TiC 2 ) of the molecule cluster type are discussed [ru

  19. FGD systems: What utilities chose in phase 1 and what they might choose in phase 2

    Energy Technology Data Exchange (ETDEWEB)

    South, D.W.; Bailey, K.A.

    1995-07-01

    Title IV (acid rain) of the Clean Air Act Amendments of 1990 is imposing new limitations on the emission of sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) from electric power plants. The Act requires utilities to develop compliance plans to reduce these emissions, and indications are that these plans will dramatically alter traditional operating procedures. A key provision of the SO{sub 2} control program defined in Title IV is the creation of a system of emission allowances, with utilities having, the option of complying by adjusting system emissions and allowance holdings. The central focus of this paper is the identification of sulfur dioxide (SO{sub 2}) control options being implemented by the electric utility industry, current compliance trends, synergistic control issues and a discussion of the implications of Phase I decisions for Phase II.

  20. Phase transitions in glassy systems via convolutional neural networks

    Science.gov (United States)

    Fang, Chao

    Machine learning is a powerful approach commonplace in industry to tackle large data sets. Most recently, it has found its way into condensed matter physics, allowing for the first time the study of, e.g., topological phase transitions and strongly-correlated electron systems. The study of spin glasses is plagued by finite-size effects due to the long thermalization times needed. Here we use convolutional neural networks in an attempt to detect a phase transition in three-dimensional Ising spin glasses. Our results are compared to traditional approaches.

  1. Phase behavior of (CO2 + methanol + lauric acid) system

    International Nuclear Information System (INIS)

    Ferreira, Franciele M.; Ramos, Luiz P.; Ndiaye, Papa M.; Corazza, Marcos L.

    2011-01-01

    Highlights: → We measured SVL, LLE and VLE for the binary system {lauric acid + methanol + CO 2 }. → Bubble point and dew point were measured at high pressures. → The experimental data were modeled using the Peng-Robinson equation of state with the classical van der Waals mixing rule. - Abstract: In this study the phase equilibrium behaviors of the binary system (CO 2 + lauric acid) and the ternary system (CO 2 + methanol + lauric acid) were determined. The static synthetic method, using a variable-volume view cell, was employed to obtain the experimental data in the temperature range of (293 to 343) K and pressures up to 24 MPa. The mole fractions of carbon dioxide were varied according to the systems as follows: (0.7524 to 0.9955) for the binary system (CO 2 + lauric acid); (0.4616 to 0.9895) for the ternary system (CO 2 + methanol + lauric acid) with a methanol to lauric acid molar ratio of (2:1); and (0.3414 to 0.9182) for the system (CO 2 + methanol + lauric acid) with a methanol to lauric acid molar ratio of (6:1). For these systems (vapor + liquid), (liquid + liquid), (vapor + liquid + liquid), and (solid + fluid) transitions were observed. The phase equilibrium data obtained for the systems were modeled using the Peng-Robinson equation of state with the classical van der Waals mixing rule with a satisfactory correlation between experimental and calculated values.

  2. An optical ASK and FSK phase diversity transmission system

    Science.gov (United States)

    Vandenboom, H.; Vanetten, W.; Dekrom, W. H. C.; Vanbennekom, P.; Huijskens, F.; Niessen, L.; Deleijer, F.

    1992-12-01

    The results of a contribution to an electrooptical project for a 'phase diversity system', covering ASK and FSK (Amplitude and Frequency Shift Keying), are described. Specifications of subsystems, and tolerances and consequences of these tolerances for the final system performance, were derived. For the optical network of the phase diversity receiver, a manufacturing set up for three by three fused biconical taper fiber couplers was developed. In order to characterize planar optical networks, a set up was constructed to measure the phase relations at 1523 nm. The optical frequency of the local oscillator laser has to be locked on to the frequency of the received optical signal. This locking circuit is described. A complete optical three by three phase diversity transmission system was developed that can be used as a testbed for subsystems. The sensitivity of the receiver at a bit error rate of 10 to the minus 9th power is -47.2 dBm, which is 4.2 dB better than the value of the specifications.

  3. Phase equilibria in the niobium-vanadium-hydrogen system

    Energy Technology Data Exchange (ETDEWEB)

    Bethin, J. (Grumman Aerospace Corp., Bethpage, NY (USA)); Welch, D.O. (Brookhaven National Lab., Upton, NY (USA)); Pick, M.A. (Commission of the European Communities, Abingdon (UK). JET Joint Undertaking)

    1990-01-01

    The effect of vanadium additions to niobium on the metal-hydrogen phase equilibria has been studied. Measurements of the equilibrium H{sub 2}(D{sub 2}) pressure-composition-temperature isotherms for Nb{sub 1-x}V{sub x} alloys with 0{le}x<0.2 were used to determine the depression of the {alpha} - {alpha}' critical temperature with increasing vanadium concentration. A simple lattice-fluid model guided reduction of the data. Changes in the triple point temperature as well as the shift of the {zeta} {yields} {epsilon} phase transition were determined by differential scanning calorimetry measurements. A rapid overall depression was found, of the order of 7 K (at.% substituted V){sup -1}, for the metal-hydrogen (deuterium) phase boundary structure when compared with the Nb-H system in the hydrogen concentration range of interest. The results explain the enhanced terminal solubility of hydrogen in this system found previously by other authors. The changes in the phase equilibria are discussed in terms of the effect of hydrogen trapping and compared with the results of a cluster-variation calculation for random-field systems of previous authors, taking into account a distribution of H-site energies due to alloying. (author).

  4. Brayton isotope power system, phase I. Final report

    International Nuclear Information System (INIS)

    1978-01-01

    The Phase I program resulted in the development and ground demonstration of a dynamic power conversion system. The two key contractual objectives of 25% conversion efficiency and 1000 h of endurance testing were successfully met. As a result of the Phase I effort, the BIPS is a viable candidate for further development into a flight system capable of sustained operation in space. It represents the only known dynamic space power system to demonstrate the performance and endurance coupled with the simplicity necessary for reliable operation. This final report follows thirty-five monthly reports. For expediency, it makes liberal use of referenced documents which have been submitted to DOE during the course of the program

  5. Phase space view of quantum mechanical systems and Fisher information

    International Nuclear Information System (INIS)

    Nagy, Á.

    2016-01-01

    Highlights: • Phase-space Fisher information coming from the canonical distribution is derived for the ground state of quantum mechanical systems. • Quantum mechanical phase-space Fisher information contains an extra term due to the position dependence of the temperature. • A complete analogy to the classical case is demonstrated for the linear harmonic oscillator. - Abstract: Pennini and Plastino showed that the form of the Fisher information generated by the canonical distribution function reflects the intrinsic structure of classical mechanics. Now, a quantum mechanical generalization of the Pennini–Plastino theory is presented based on the thermodynamical transcription of the density functional theory. Comparing to the classical case, the phase-space Fisher information contains an extra term due to the position dependence of the temperature. However, for the special case of constant temperature, the expression derived bears resemblance to the classical one. A complete analogy to the classical case is demonstrated for the linear harmonic oscillator.

  6. Phase space view of quantum mechanical systems and Fisher information

    Energy Technology Data Exchange (ETDEWEB)

    Nagy, Á., E-mail: anagy@madget.atomki.hu

    2016-06-17

    Highlights: • Phase-space Fisher information coming from the canonical distribution is derived for the ground state of quantum mechanical systems. • Quantum mechanical phase-space Fisher information contains an extra term due to the position dependence of the temperature. • A complete analogy to the classical case is demonstrated for the linear harmonic oscillator. - Abstract: Pennini and Plastino showed that the form of the Fisher information generated by the canonical distribution function reflects the intrinsic structure of classical mechanics. Now, a quantum mechanical generalization of the Pennini–Plastino theory is presented based on the thermodynamical transcription of the density functional theory. Comparing to the classical case, the phase-space Fisher information contains an extra term due to the position dependence of the temperature. However, for the special case of constant temperature, the expression derived bears resemblance to the classical one. A complete analogy to the classical case is demonstrated for the linear harmonic oscillator.

  7. Dissipation-driven quantum phase transitions in collective spin systems

    International Nuclear Information System (INIS)

    Morrison, S; Parkins, A S

    2008-01-01

    We consider two different collective spin systems subjected to strong dissipation-on the same scale as interaction strengths and external fields-and show that either continuous or discontinuous dissipative quantum phase transitions can occur as the dissipation strength is varied. First, we consider a well-known model of cooperative resonance fluorescence that can exhibit a second-order quantum phase transition, and analyse the entanglement properties near the critical point. Next, we examine a dissipative version of the Lipkin-Meshkov-Glick interacting collective spin model, where we find that either first- or second-order quantum phase transitions can occur, depending only on the ratio of the interaction and external field parameters. We give detailed results and interpretation for the steady-state entanglement in the vicinity of the critical point, where it reaches a maximum. For the first-order transition we find that the semiclassical steady states exhibit a region of bistability. (fast track communication)

  8. Ferroelectric properties of tungsten bronze morphotropic phase boundary systems

    International Nuclear Information System (INIS)

    Oliver, J.R.; Neurgaonkar, R.R.; Cross, L.E.; Pennsylvania State Univ., University Park, PA

    1989-01-01

    Tungsten bronze ferroelectrics which have a morphotropic phase boundary (MPB) can have a number or enhanced dielectric, piezoelectric, and electrooptic properties compared to more conventional ferroelectric materials. The structural and ferroelectric properties of several MPB bronze systems are presented, including data from sintered and hot-pressed ceramics, epitaxial thin films, and bulk single crystals. Included among these are three systems which had not been previously identified as morphotropic. The potential advantages and limitations of these MPB systems are discussed, along with considerations of the appropriate growth methods for their possible utilization in optical, piezoelectric, or pyroelectric device applications

  9. Phase change thermal storage for a solar total energy system

    Science.gov (United States)

    Rice, R. E.; Cohen, B. M.

    1978-01-01

    An analytical and experimental program is being conducted on a one-tenth scale model of a high-temperature (584 K) phase-change thermal energy storage system for installation in a solar total energy test facility at Albuquerque, New Mexico, U.S.A. The thermal storage medium is anhydrous sodium hydroxide with 8% sodium nitrate. The program will produce data on the dynamic response of the system to repeated cycles of charging and discharging simulating those of the test facility. Data will be correlated with a mathematical model which will then be used in the design of the full-scale system.

  10. Quantum phase transitions of strongly correlated electron systems

    International Nuclear Information System (INIS)

    Imada, Masatoshi

    1998-01-01

    Interacting electrons in solids undergo various quantum phase transitions driven by quantum fluctuations. The quantum transitions take place at zero temperature by changing a parameter to control quantum fluctuations rather than thermal fluctuations. In contrast to classical phase transitions driven by thermal fluctuations, the quantum transitions have many different features where quantum dynamics introduces a source of intrinsic fluctuations tightly connected with spatial correlations and they have been a subject of recent intensive studies as we see below. Interacting electron systems cannot be fully understood without deep analyses of the quantum phase transitions themselves, because they are widely seen and play essential roles in many phenomena. Typical and important examples of the quantum phase transitions include metal-insulator transitions, (2, 3, 4, 5, 6, 7, 8, 9) metal-superconductor transitions, superconductor-insulator transitions, magnetic transitions to antiferromagnetic or ferromagnetic phases in metals as well as in Mott insulators, and charge ordering transitions. Here, we focus on three different types of transitions

  11. Intelligent System for Diagnosis of a Three-Phase Separator

    Directory of Open Access Journals (Sweden)

    Irina Ioniţă

    2016-03-01

    Full Text Available Intelligent systems for diagnosis have been used in a variety of domains: financial evaluation, credit scoring problem, identification of software and hardware problems of mechanical and electronic equipment, medical diagnosis, fault detection in gas-oil production plants etc. The goal of diagnosis systems is to classify the observed symptoms as being caused by some diagnosis class while advising systems perform such a classification and offer corrective remedies (recommendations. The current paper discuss the opportunity to combine more intelligent techniques and methodologies (intelligent agents, data mining and expert systems to increase the accuracy of results obtained from the diagnosis of a three-phase separator. The results indicate that the diagnosis hybrid system benefits from the advantages of each module component: intelligent agent module, data mining module and expert system module.

  12. Electric vehicles batteries thermal management systems employing phase change materials

    Science.gov (United States)

    Ianniciello, Lucia; Biwolé, Pascal Henry; Achard, Patrick

    2018-02-01

    Battery thermal management is necessary for electric vehicles (EVs), especially for Li-ion batteries, due to the heat dissipation effects on those batteries. Usually, air or coolant circuits are employed as thermal management systems in Li-ion batteries. However, those systems are expensive in terms of investment and operating costs. Phase change materials (PCMs) may represent an alternative which could be cheaper and easier to operate. In fact, PCMs can be used as passive or semi-passive systems, enabling the global system to sustain near-autonomous operations. This article presents the previous developments introducing PCMs for EVs battery cooling. Different systems are reviewed and solutions are proposed to enhance PCMs efficiency in those systems.

  13. Phase transition universality classes of classical, nonequilibrium systems

    CERN Document Server

    Ódor, G

    2004-01-01

    In the first chapter I summarize the most important critical exponents and relations used in this work. In the second chapter I briefly address the question of scaling behavior at first order phase transitions.In chapter three I review dynamical extensions of basic static classes, show the effect of mixing dynamics and percolation behavior. The main body of this work is given in chapter four where genuine, dynamical universality classes specific to nonequilibrium systems are introduced. In chapter five I continue overviewing such nonequilibrium classes but in coupled, multi-component systems. Most of known transitions in low dimensional systems are between active and absorbing states of reaction-diffusion type systems, but I briefly introduce related classes that appear in interface growth models in chapter six. Some of them are related to critical behavior of coupled, multi-component systems. Finally in chapter seven I summarize families of absorbing state system classes, mean-field classes and the most freq...

  14. Three-Phase Harmonic Analysis Method for Unbalanced Distribution Systems

    Directory of Open Access Journals (Sweden)

    Jen-Hao Teng

    2014-01-01

    Full Text Available Due to the unbalanced features of distribution systems, a three-phase harmonic analysis method is essential to accurately analyze the harmonic impact on distribution systems. Moreover, harmonic analysis is the basic tool for harmonic filter design and harmonic resonance mitigation; therefore, the computational performance should also be efficient. An accurate and efficient three-phase harmonic analysis method for unbalanced distribution systems is proposed in this paper. The variations of bus voltages, bus current injections and branch currents affected by harmonic current injections can be analyzed by two relationship matrices developed from the topological characteristics of distribution systems. Some useful formulas are then derived to solve the three-phase harmonic propagation problem. After the harmonic propagation for each harmonic order is calculated, the total harmonic distortion (THD for bus voltages can be calculated accordingly. The proposed method has better computational performance, since the time-consuming full admittance matrix inverse employed by the commonly-used harmonic analysis methods is not necessary in the solution procedure. In addition, the proposed method can provide novel viewpoints in calculating the branch currents and bus voltages under harmonic pollution which are vital for harmonic filter design. Test results demonstrate the effectiveness and efficiency of the proposed method.

  15. Phase chemistry of the system Nb–Rh–O

    International Nuclear Information System (INIS)

    Jacob, K.T.; Gupta, Preeti; Vinay, M.; Waseda, Y.

    2013-01-01

    Phase relations in the system Nb–Rh–O at 1223 K were investigated by isothermal equilibration of eleven compositions and analysis of quenched samples using OM, XRD, SEM and EDS. The oxide phase in equilibrium with the alloy changes progressively from NbO to NbO 2 , NbO 2.422 and Nb 2 O 5−x with increasing Rh. Only one ternary oxide NbRhO 4 with tetragonal structure (a=0.4708 nm and c=0.3017 nm) was detected. It coexists with Rh and Nb 2 O 5 . The standard Gibbs energy of formation of NbRhO 4 from its component binary oxides measured using a solid-state electrochemical cell can be represented by the equation; ΔG f,ox o (J/mol)=−38,350+5.818×T(±96) Constructed on the basis of thermodynamic information of the various alloy and oxide phases are oxygen potential diagram for the system Nb–Rh–O at 1223 K and temperature–composition diagrams at constant partial pressures of oxygen. - Graphical abstract: Isothermal section of ternary phase diagram for the system Nb–Rh–O at 1223 K. - Highlights: • First complete isothermal section for the system Nb–Rh–O has been established. • An electrochemical cell is used to measure the thermodynamic properties of NbRhO 4 . • Oxygen potential diagram at 1223 K is computed from thermodynamic data. • Temperature–composition diagrams at constant oxygen partial pressures. • A complete thermodynamic characterization of the system Nb–Rh–O is presented

  16. Phase chemistry of the system Nb–Rh–O

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, K.T., E-mail: katob@materials.iisc.ernet.in [Department of Materials Engineering, Indian Institute of Science, Bangalore 560012 (India); Gupta, Preeti; Vinay, M. [Department of Materials Engineering, Indian Institute of Science, Bangalore 560012 (India); Waseda, Y. [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan)

    2013-06-01

    Phase relations in the system Nb–Rh–O at 1223 K were investigated by isothermal equilibration of eleven compositions and analysis of quenched samples using OM, XRD, SEM and EDS. The oxide phase in equilibrium with the alloy changes progressively from NbO to NbO₂, NbO₂.₄₂₂ and Nb₂O5–x with increasing Rh. Only one ternary oxide NbRhO₄ with tetragonal structure (a=0.4708 nm and c=0.3017 nm) was detected. It coexists with Rh and Nb₂O₅. The standard Gibbs energy of formation of NbRhO₄ from its component binary oxides measured using a solid-state electrochemical cell can be represented by the equation; ΔGf,oxo(J/mol)=-38,350+5.818×T(±96) Constructed on the basis of thermodynamic information of the various alloy and oxide phases are oxygen potential diagram for the system Nb–Rh–O at 1223 K and temperature–composition diagrams at constant partial pressures of oxygen. - Graphical abstract: Isothermal section of ternary phase diagram for the system Nb–Rh–O at 1223 K. Highlights: • First complete isothermal section for the system Nb–Rh–O has been established. • An electrochemical cell is used to measure the thermodynamic properties of NbRhO₄. • Oxygen potential diagram at 1223 K is computed from thermodynamic data. • Temperature–composition diagrams at constant oxygen partial pressures. • A complete thermodynamic characterization of the system Nb–Rh–O is presented.

  17. Phase change energy storage for solar dynamic power systems

    Science.gov (United States)

    Chiaramonte, F. P.; Taylor, J. D.

    1992-01-01

    This paper presents the results of a transient computer simulation that was developed to study phase change energy storage techniques for Space Station Freedom (SSF) solar dynamic (SD) power systems. Such SD systems may be used in future growth SSF configurations. Two solar dynamic options are considered in this paper: Brayton and Rankine. Model elements consist of a single node receiver and concentrator, and takes into account overall heat engine efficiency and power distribution characteristics. The simulation not only computes the energy stored in the receiver phase change material (PCM), but also the amount of the PCM required for various combinations of load demands and power system mission constraints. For a solar dynamic power system in low earth orbit, the amount of stored PCM energy is calculated by balancing the solar energy input and the energy consumed by the loads corrected by an overall system efficiency. The model assumes an average 75 kW SD power system load profile which is connected to user loads via dedicated power distribution channels. The model then calculates the stored energy in the receiver and subsequently estimates the quantity of PCM necessary to meet peaking and contingency requirements. The model can also be used to conduct trade studies on the performance of SD power systems using different storage materials.

  18. Adiabatically steered open quantum systems: Master equation and optimal phase

    International Nuclear Information System (INIS)

    Salmilehto, J.; Solinas, P.; Ankerhold, J.; Moettoenen, M.

    2010-01-01

    We introduce an alternative way to derive the generalized form of the master equation recently presented by J. P. Pekola et al. [Phys. Rev. Lett. 105, 030401 (2010)] for an adiabatically steered two-level quantum system interacting with a Markovian environment. The original derivation employed the effective Hamiltonian in the adiabatic basis with the standard interaction picture approach but without the usual secular approximation. Our approach is based on utilizing a master equation for a nonsteered system in the first superadiabatic basis. It is potentially efficient in obtaining higher-order equations. Furthermore, we show how to select the phases of the adiabatic eigenstates to minimize the local adiabatic parameter and how this selection leads to states which are invariant under a local gauge change. We also discuss the effects of the adiabatic noncyclic geometric phase on the master equation.

  19. Photon detection system for ProtoDUNE dual phase

    CERN Document Server

    Cuesta, C. (on behalf of DUNE collaboration)

    2017-01-01

    The Deep Underground Neutrino Experiment (DUNE) is a 40-kton underground liquid argon time-projection-chamber (LAr TPC) detector, for long-baseline neutrino oscillation studies and for neutrino astrophysics and nucleon decay searches. Photon detector systems embedded within the LAr TPC add precise timing capabilities for non-beam events. The ProtoDUNE dual phase detector will consist of a 6x6x6 m3 liquid argon time-projection chamber placed at CERN and the light readout will be formed by 8-inch cryogenic photomultipliers from Hamamatsu. The characterization of the 36 photomultipliers, the base design, and the light calibration system are described. In addition, preliminary results from a 3x1x1 m3 LAr double phase detector operating at CERN are presented.

  20. Bunching phase evolution of short-pulse FEL oscillator system

    CERN Document Server

    Song, S B; Choi, D I

    2000-01-01

    We studied numerically the short-pulse FEL oscillator system using properly defined bunching phase theta sub B and PSI sub B. In stable operation, we have found that the optical field 'locks' the phase to pi/2 at the trailing edge, which gives the maximum gain. Moreover, electrons can be detrapped from ponderomotive bucket due to the spatial variation of the optical field, and this detrapping effect is a major cause of the limit cycle oscillation of the system. The 'bump' of the output power during the amplification usually exists at the near-perfect cavity synchronism regime, which can be explained as the change of the matching condition between electron micropulse and optical pulse.

  1. Field-induced phase transitions in antiferromagnetic systems

    International Nuclear Information System (INIS)

    Smeets, J.P.M.

    1984-05-01

    Neutron scattering experiments and magnetization measurements are carried out on cobalt bromide hexahydrate, of which 48% of the water molecules are replaced by deuterium oxide molecules. Results were compared with data obtained from non-deuterated cobalt bromide hexahydrate. Neutron scattering experiments showed the importance of the deuterium fraction. Interplay exists between the crystallographic system and the magnetic system, which is influenced by changing the deuterium fraction. Neutron scattering and magnetization experiments on partially deuterated RbFeCl 3 .2H 2 O and CsFeCl 3 .2H 2 O were performed to study the magnetic phase transitions in these quasi one-dimensional Ising compounds. The observed behaviour in the various phases can be described by the nucleation theory of chain reversals. (Auth.)

  2. Universal phase diagram for high-piezoelectric perovskite systems

    NARCIS (Netherlands)

    Cox, D.E.; Noheda, B.; Shirane, G.; Uesu, Y.; Fujishiro, K.; Yamada, Y.

    2001-01-01

    Strong piezoelectricity in perovskite-type PbZn1-xTixO3 (PZT) and Pb(Zn1/3Nb2/3)O3–PbTiO3 (PZN–PT) systems is generally associated with the existence of a morphotropic phase boundary (MPB) separating regions with rhombohedral and tetragonal symmetry. An x-ray study of PZN–9% PT has revealed the

  3. BOA: Asbestos pipe insulation removal robot system. Phase 1

    Energy Technology Data Exchange (ETDEWEB)

    Schempf, H.; Bares, J.E.

    1995-02-01

    The project described in this report targets the development of a mechanized system for safe, cost-efficient and automated abatement of asbestos containing materials used as pipe insulation. Based on several key design criteria and site visits, a proof-of-concept prototype robot system, dubbed BOA, was designed and built, which automatically strips the lagging and insulation from the pipes, and encapsulates them under complete vacuum operation. The system can operate on straight runs of piping in horizontal or vertical orientations. Currently we are limited to four-inch diameter piping without obstacles as well as a somewhat laborious emplacement and removal procedure -- restrictions to be alleviated through continued development. BOA removed asbestos at a rate of 4-5 ft./h compared to 3 ft./h for manual removal of asbestos with a 3-person crew. The containment and vacuum system on BOA was able to achieve the regulatory requirement for airborne fiber emissions of 0.01 fibers/ccm/ 8-hr. shift. This program consists of two phases. The first phase was completed and a demonstration was given to a review panel, consisting of DOE headquarters and site representatives as well as commercial abatement industry representatives. Based on the technical and programmatic recommendations drafted, presented and discussed during the review meeting, a new plan for the Phase II effort of this project was developed. Phase 11 will consist of a 26-month effort, with an up-front 4-month site-, market-, cost/benefit and regulatory study before the next BOA robot (14 months) is built, and then deployed and demonstrated (3 months) at a DOE site (such as Fernald or Oak Ridge) by the beginning of FY`97.

  4. Automatic Identification System (AIS) Transmit Testing in Louisville Phase 2

    Science.gov (United States)

    2014-08-01

    Firewall Louisville QM 65.206.28.x NAIS Site Controller PC RS232 Serial cable TV32 Computer Cmd Center Serial splitter SAAB R40 AIS Base Station...172.17.14.6 Rack mount computer AIS Radio Interface Ethernet Switch 192.168.0.x Firewall Cable Modem 192.168.0.1 VTS Accred. Boundary serial connection...Automatic Identification System ( AIS ) Transmit Testing in Louisville Phase 2 Distribution Statement A: Approved for public release

  5. Beam Position and Phase Monitor - Wire Mapping System

    International Nuclear Information System (INIS)

    Watkins, Heath A.; Shurter, Robert B.; Gilpatrick, John D.; Kutac, Vincent G.; Martinez, Derwin

    2012-01-01

    The Los Alamos Neutron Science Center (LANSCE) deploys many cylindrical beam position and phase monitors (BPPM) throughout the linac to measure the beam central position, phase and bunched-beam current. Each monitor is calibrated and qualified prior to installation to insure it meets LANSCE requirements. The BPPM wire mapping system is used to map the BPPM electrode offset, sensitivity and higher order coefficients. This system uses a three-axis motion table to position the wire antenna structure within the cavity, simulating the beam excitation of a BPPM at a fundamental frequency of 201.25 MHz. RF signal strength is measured and recorded for the four electrodes as the antenna position is updated. An effort is underway to extend the systems service to the LANSCE facility by replacing obsolete electronic hardware and taking advantage of software enhancements. This paper describes the upgraded wire positioning system's new hardware and software capabilities including its revised antenna structure, motion control interface, RF measurement equipment and Labview software upgrades. The main purpose of the wire mapping system at LANSCE is to characterize the amplitude response versus beam central position of BPPMs before they are installed in the beam line. The wire mapping system is able to simulate a beam using a thin wire and measure the signal response as the wire position is varied within the BPPM aperture.

  6. Solar central receiver hybrid power system. Phase I study

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-11-01

    A management plan is presented for implementation during the Solar Central Receiver Hybrid Power System - Phase I study project. The project plan and the management controls that will be used to assure technically adequate, timely and cost effective performance of the work required to prepare the designated end products are described. Bechtel in-house controls and those to be used in directing the subcontractors are described. Phase I of the project consists of tradeoff studies, parametric analyses, and engineering studies leading to conceptual definition and evaluation of a commercial hybrid power system that has the potential for supplying economically competitive electric power to a utility grid in the 1985-1990 time frame. The scope also includes the preparation of a development plan for the resolution of technical uncertainties and the preparation of plans and a proposal for Phase II of the program. The technical approach will be based on a central receiver solar energy collection scheme which supplies thermal energy to a combined cycle, generating system, consisting of a gas turbine cycle combined with a steam bottoming cycle by means of a heat recovery steam generator.

  7. Competition for synchronization in a phase oscillator system

    Science.gov (United States)

    Kazanovich, Yakov; Burylko, Oleksandr; Borisyuk, Roman

    2013-10-01

    A system of phase oscillators with a Central Oscillator (CO) and a set of n Peripheral Oscillators (POs) is considered. Feed-forward and feedback connections between the CO and POs are determined by two interaction functions which are assumed to be smooth, odd, and periodic. To describe the competition of POs for synchronization with the CO, we study the asymptotic stability of fixed points corresponding to in-phase synchronization of a group of k POs, while other POs are in anti-phase with the CO. It is shown that stability conditions can be formulated in terms of four parameters that describe the slopes of the interaction functions at zero and half-period points. Analytical description of stability in terms of the regions in 4-dimensional parameter space is given. Combining stability analysis with the detailed study of geometry of invariant manifolds, the bifurcations of fixed points are investigated. We show that various dynamical regimes such as multistability, heteroclinic orbits, and chaos are possible. Analytical stability conditions for global synchronization of POs with the CO are formulated for the systems with local connections between POs. It is shown that synchronization in a large system with local connections becomes unstable even under weak desynchronizing influence from the CO. The application of the results to modeling in neuroscience and, in particular, for modeling visual attention is discussed.

  8. Diffusion and phase growth in heterophase systems. 1

    International Nuclear Information System (INIS)

    Mchedlov-Petrosyan, P.O.

    1989-01-01

    The present paper gives the view of theoretical study of diffusion processes in ternary and more component solid-state systems, caused by chemical reactions and phase growth. Internal oxidation of alloys, nitridation, borating etc. are the well-known and widely investigated processes of such type. Self-consistent theoretical model of such processes must take into account both the effect of concentration macroscopic districutions on new phase precipitation growth and precipitation reaction on concentration distribution; heterophase must be explicitly allowed for. As for binary system, diffusion theory, running into the phase growth, is well developed and completely presented in monographs, the carried out theoretical investigations of ternary systems are explicitly deficient. The first part of the review presents analysis of available theoretical studies approximately up to 1980. Ratios between various analytically solved models are discussed in detail. It is shown that they don't satisfy to full extent the above-given requirements. More consistent, both numerically and analytically solvable models developed for the last years, are considered in the review second part. 119 refs

  9. Choice of optical system is critical for the security of double random phase encryption systems

    Science.gov (United States)

    Muniraj, Inbarasan; Guo, Changliang; Malallah, Ra'ed; Cassidy, Derek; Zhao, Liang; Ryle, James P.; Healy, John J.; Sheridan, John T.

    2017-06-01

    The linear canonical transform (LCT) is used in modeling a coherent light-field propagation through first-order optical systems. Recently, a generic optical system, known as the quadratic phase encoding system (QPES), for encrypting a two-dimensional image has been reported. In such systems, two random phase keys and the individual LCT parameters (α,β,γ) serve as secret keys of the cryptosystem. It is important that such encryption systems also satisfy some dynamic security properties. We, therefore, examine such systems using two cryptographic evaluation methods, the avalanche effect and bit independence criterion, which indicate the degree of security of the cryptographic algorithms using QPES. We compared our simulation results with the conventional Fourier and the Fresnel transform-based double random phase encryption (DRPE) systems. The results show that the LCT-based DRPE has an excellent avalanche and bit independence characteristics compared to the conventional Fourier and Fresnel-based encryption systems.

  10. Renormalization group theory of phase transitions in square Ising systems

    International Nuclear Information System (INIS)

    Nienhuis, B.

    1978-01-01

    Some renormalization group calculations are presented on a number of phase transitions in a square Ising model, both second and first order. Of these transitions critical exponents are calculated, the amplitudes of the power law divergences and the locus of the transition. In some cases attention is paid to the thermodynamic functions also far from the critical point. Universality and scaling are discussed and the renormalization group theory is reviewed. It is shown how a renormalization transformation, which relates two similar systems with different macroscopic dimensions, can be constructed, and how some critical properties of the system follow from this transformation. Several numerical and analytical applications are presented. (Auth.)

  11. Physics Detector Simulation Facility Phase II system software description

    International Nuclear Information System (INIS)

    Scipioni, B.; Allen, J.; Chang, C.; Huang, J.; Liu, J.; Mestad, S.; Pan, J.; Marquez, M.; Estep, P.

    1993-05-01

    This paper presents the Physics Detector Simulation Facility (PDSF) Phase II system software. A key element in the design of a distributed computing environment for the PDSF has been the separation and distribution of the major functions. The facility has been designed to support batch and interactive processing, and to incorporate the file and tape storage systems. By distributing these functions, it is often possible to provide higher throughput and resource availability. Similarly, the design is intended to exploit event-level parallelism in an open distributed environment

  12. Dynamical tunneling in systems with a mixed phase space

    International Nuclear Information System (INIS)

    Loeck, Steffen

    2010-01-01

    Tunneling is one of the most prominent features of quantum mechanics. While the tunneling process in one-dimensional integrable systems is well understood, its quantitative prediction for systems with a mixed phase space is a long-standing open challenge. In such systems regions of regular and chaotic dynamics coexist in phase space, which are classically separated but quantum mechanically coupled by the process of dynamical tunneling. We derive a prediction of dynamical tunneling rates which describe the decay of states localized inside the regular region towards the so-called chaotic sea. This approach uses a fictitious integrable system which mimics the dynamics inside the regular domain and extends it into the chaotic region. Excellent agreement with numerical data is found for kicked systems, billiards, and optical microcavities, if nonlinear resonances are negligible. Semiclassically, however, such nonlinear resonance chains dominate the tunneling process. Hence, we combine our approach with an improved resonance-assisted tunneling theory and derive a unified prediction which is valid from the quantum to the semiclassical regime. We obtain results which show a drastically improved accuracy of several orders of magnitude compared to previous studies. (orig.)

  13. Dynamical tunneling in systems with a mixed phase space

    Energy Technology Data Exchange (ETDEWEB)

    Loeck, Steffen

    2010-04-22

    Tunneling is one of the most prominent features of quantum mechanics. While the tunneling process in one-dimensional integrable systems is well understood, its quantitative prediction for systems with a mixed phase space is a long-standing open challenge. In such systems regions of regular and chaotic dynamics coexist in phase space, which are classically separated but quantum mechanically coupled by the process of dynamical tunneling. We derive a prediction of dynamical tunneling rates which describe the decay of states localized inside the regular region towards the so-called chaotic sea. This approach uses a fictitious integrable system which mimics the dynamics inside the regular domain and extends it into the chaotic region. Excellent agreement with numerical data is found for kicked systems, billiards, and optical microcavities, if nonlinear resonances are negligible. Semiclassically, however, such nonlinear resonance chains dominate the tunneling process. Hence, we combine our approach with an improved resonance-assisted tunneling theory and derive a unified prediction which is valid from the quantum to the semiclassical regime. We obtain results which show a drastically improved accuracy of several orders of magnitude compared to previous studies. (orig.)

  14. Glass and liquid phase diagram of a polyamorphic monatomic system

    Science.gov (United States)

    Reisman, Shaina; Giovambattista, Nicolas

    2013-02-01

    We perform out-of-equilibrium molecular dynamics (MD) simulations of a monatomic system with Fermi-Jagla (FJ) pair potential interactions. This model system exhibits polyamorphism both in the liquid and glass state. The two liquids, low-density (LDL) and high-density liquid (HDL), are accessible in equilibrium MD simulations and can form two glasses, low-density (LDA) and high-density amorphous (HDA) solid, upon isobaric cooling. The FJ model exhibits many of the anomalous properties observed in water and other polyamorphic liquids and thus, it is an excellent model system to explore qualitatively the thermodynamic properties of such substances. The liquid phase behavior of the FJ model system has been previously characterized. In this work, we focus on the glass behavior of the FJ system. Specifically, we perform systematic isothermal compression and decompression simulations of LDA and HDA at different temperatures and determine "phase diagrams" for the glass state; these phase diagrams varying with the compression/decompression rate used. We obtain the LDA-to-HDA and HDA-to-LDA transition pressure loci, PLDA-HDA(T) and PHDA-LDA(T), respectively. In addition, the compression-induced amorphization line, at which the low-pressure crystal (LPC) transforms to HDA, PLPC-HDA(T), is determined. As originally proposed by Poole et al. [Phys. Rev. E 48, 4605 (1993)], 10.1103/PhysRevE.48.4605 simulations suggest that the PLDA-HDA(T) and PHDA-LDA(T) loci are extensions of the LDL-to-HDL and HDL-to-LDL spinodal lines into the glass domain. Interestingly, our simulations indicate that the PLPC-HDA(T) locus is an extension, into the glass domain, of the LPC metastability limit relative to the liquid. We discuss the effects of compression/decompression rates on the behavior of the PLDA-HDA(T), PHDA-LDA(T), PLPC-HDA(T) loci. The competition between glass polyamorphism and crystallization is also addressed. At our "fast rate," crystallization can be partially suppressed and the

  15. Efficient Phase Locking of Fiber Amplifiers Using a Low-Cost and High-Damage-Threshold Phase Control System

    International Nuclear Information System (INIS)

    Pu, Zhou; Yan-Xing, Ma; Xiao-Lin, Wang; Hao-Tong, Ma; Xiao-Jun, Xu; Ze-Jin, Liu

    2010-01-01

    We propose a low-cost and high-damage-threshold phase control system that employs a piezoelectric ceramic transducer modulator controlled by a stochastic parallel gradient descent algorithm. Efficient phase locking of two fiber amplifiers is demonstrated. Experimental results show that energy encircled in the target pinhole is increased by a factor of 1.76 and the visibility of the fringe pattern is as high as 90% when the system is in close-loop. The phase control system has potential in phase locking of large-number and high-power fiber laser endeavors. (fundamental areas of phenomenology (including applications))

  16. Quantum phase transition in strongly correlated many-body system

    Science.gov (United States)

    You, Wenlong

    The past decade has seen a substantial rejuvenation of interest in the study of quantum phase transitions (QPTs), driven by experimental advance on the cuprate superconductors, the heavy fermion materials, organic conductors, Quantum Hall effect, Fe-As based superconductors and other related compounds. It is clear that strong electronic interactions play a crucial role in the systems of current interest, and simple paradigms for the behavior of such systems near quantum critical points remain unclear. Furthermore, the rapid progress in Feshbach resonance and optical lattice provides a flexible platform to study QPT. Quantum Phase Transition (QPT) describes the non-analytic behaviors of the ground-state properties in a many-body system by varying a physical parameter at absolute zero temperature - such as magnetic field or pressure, driven by quantum fluctuations. Such quantum phase transitions can be first-order phase transition or continuous. The phase transition is usually accompanied by a qualitative change in the nature of the correlations in the ground state, and describing this change shall clearly be one of our major interests. We address this issue from three prospects in a few strong correlated many-body systems in this thesis, i.e., identifying the ordered phases, studying the properties of different phases, characterizing the QPT points. In chapter 1, we give an introduction to QPT, and take one-dimensional XXZ model as an example to illustrate the QPT therein. Through this simple example, we would show that when the tunable parameter is varied, the system evolves into different phases, across two quantum QPT points. The distinct phases exhibit very different behaviors. Also a schematic phase diagram is appended. In chapter 2, we are engaged in research on ordered phases. Originating in the work of Landau and Ginzburg on second-order phase transition, the spontaneous symmetry breaking induces nonzero expectation of field operator, e.g., magnetization M

  17. Phase II Vault Testing of the Argonne RFID System

    International Nuclear Information System (INIS)

    Willoner, T.; Turlington, R.; Koenig, R.

    2012-01-01

    The U.S. Department of Energy (DOE) (Environmental Management (EM), Office of Packaging and Transportation (EM-45)) Packaging and Certification Program (DOE PCP) has developed a Radio Frequency Identification (RFID) tracking and monitoring system, called ARG-US, for the management of nuclear materials packages during transportation and storage. The performance of the ARG-US RFID equipment and system has been fully tested in two demonstration projects in April 2008 and August 2009. With the strong support of DOE-SR and DOE PCP, a field testing program was completed in Savannah River Site's K-Area Material Storage (KAMS) Facility, an active Category I Plutonium Storage Facility, in 2010. As the next step (Phase II) of continued vault testing for the ARG-US system, the Savannah River Site K Area Material Storage facility has placed the ARG-US RFIDs into the 910B storage vault for operational testing. This latest version (Mark III) of the Argonne RFID system now has the capability to measure radiation dose and dose rate. This paper will report field testing progress of the ARG-US RFID equipment in KAMS, the operability and reliability trend results associated with the applications of the system, and discuss the potential benefits in enhancing safety, security and materials accountability. The purpose of this Phase II K Area test is to verify the accuracy of the radiation monitoring and proper functionality of the ARG-US RFID equipment and system under a realistic environment in the KAMS facility. Deploying the ARG-US RFID system leads to a reduced need for manned surveillance and increased inventory periods by providing real-time access to status and event history traceability, including environmental condition monitoring and radiation monitoring. The successful completion of the testing program will provide field data to support a future development and testing. This will increase Operation efficiency and cost effectiveness for vault operation. As the next step (Phase

  18. PHASE II VAULT TESTING OF THE ARGONNE RFID SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Willoner, T.; Turlington, R.; Koenig, R.

    2012-06-25

    The U.S. Department of Energy (DOE) (Environmental Management [EM], Office of Packaging and Transportation [EM-45]) Packaging and Certification Program (DOE PCP) has developed a Radio Frequency Identification (RFID) tracking and monitoring system, called ARG-US, for the management of nuclear materials packages during transportation and storage. The performance of the ARG-US RFID equipment and system has been fully tested in two demonstration projects in April 2008 and August 2009. With the strong support of DOE-SR and DOE PCP, a field testing program was completed in Savannah River Site's K-Area Material Storage (KAMS) Facility, an active Category I Plutonium Storage Facility, in 2010. As the next step (Phase II) of continued vault testing for the ARG-US system, the Savannah River Site K Area Material Storage facility has placed the ARG-US RFIDs into the 910B storage vault for operational testing. This latest version (Mark III) of the Argonne RFID system now has the capability to measure radiation dose and dose rate. This paper will report field testing progress of the ARG-US RFID equipment in KAMS, the operability and reliability trend results associated with the applications of the system, and discuss the potential benefits in enhancing safety, security and materials accountability. The purpose of this Phase II K Area test is to verify the accuracy of the radiation monitoring and proper functionality of the ARG-US RFID equipment and system under a realistic environment in the KAMS facility. Deploying the ARG-US RFID system leads to a reduced need for manned surveillance and increased inventory periods by providing real-time access to status and event history traceability, including environmental condition monitoring and radiation monitoring. The successful completion of the testing program will provide field data to support a future development and testing. This will increase Operation efficiency and cost effectiveness for vault operation. As the next step

  19. Gaussian dominance and phase transitions in systems with continuous symmetry

    International Nuclear Information System (INIS)

    Sankovich, D.P.

    1989-01-01

    In the framework of Froehlich's strategy in the theory of phase transitions in systems with continuous symmetry a condition on the interaction is obtained that leads to the existence of a Bose condensate in the model of a nonideal Bose gas at sufficiently low temperatures. It is shown that this conditions can be satisfied for the Huang-Davis and Huang-Yang-Luttinger models. The technique of majorizing estimates for the correlation functions based on the condition of local Gaussian dominance is used. An equation is obtained for the phase-transition temperature, an upper bound is obtained for the energy of the elementary excitations, and Bogolyubov's 1/q 2 singularity theorem is generalized

  20. Urban Integrated Industrial Cogeneration Systems Analysis. Phase II final report

    Energy Technology Data Exchange (ETDEWEB)

    1984-01-01

    Through the Urban Integrated Industrial Cogeneration Systems Analysis (UIICSA), the City of Chicago embarked upon an ambitious effort to identify the measure the overall industrial cogeneration market in the city and to evaluate in detail the most promising market opportunities. This report discusses the background of the work completed during Phase II of the UIICSA and presents the results of economic feasibility studies conducted for three potential cogeneration sites in Chicago. Phase II focused on the feasibility of cogeneration at the three most promising sites: the Stockyards and Calumet industrial areas, and the Ford City commercial/industrial complex. Each feasibility case study considered the energy load requirements of the existing facilities at the site and the potential for attracting and serving new growth in the area. Alternative fuels and technologies, and ownership and financing options were also incorporated into the case studies. Finally, site specific considerations such as development incentives, zoning and building code restrictions and environmental requirements were investigated.

  1. Dynamics of energy storage in phase change drywall systems

    Energy Technology Data Exchange (ETDEWEB)

    Darkwa, K.; Kim, J.-S. [Nottingham Trent University (United Kingdom). School of the Built Environment

    2005-07-01

    Experimental evaluations of manufactured samples of laminated and randomly mixed phase change material (PCM) drywalls have been carried out and compared with numerical results. The analysis showed that the laminated PCM drywall performed thermally better. Even though there was a maximum 3% deviation of the average experimental result from the numerical values, the laminated PCM board achieved about 55% of the phase change process as against 48% for the randomly distributed drywall sample. The laminated board sample also released about 27% more latent heat than the randomly distributed type at the optimum time of 90 min thus validating previous simulation study. Given the experimental conditions and assumptions the experiment has proved that it is feasible to develop the laminated PCM technique for enhancing and minimising multi-dimensional heat transfers in drywall systems. Further practical developments are however encouraged to improve the overall level of heat transfer. (author)

  2. An expert system based software sizing tool, phase 2

    Science.gov (United States)

    Friedlander, David

    1990-01-01

    A software tool was developed for predicting the size of a future computer program at an early stage in its development. The system is intended to enable a user who is not expert in Software Engineering to estimate software size in lines of source code with an accuracy similar to that of an expert, based on the program's functional specifications. The project was planned as a knowledge based system with a field prototype as the goal of Phase 2 and a commercial system planned for Phase 3. The researchers used techniques from Artificial Intelligence and knowledge from human experts and existing software from NASA's COSMIC database. They devised a classification scheme for the software specifications, and a small set of generic software components that represent complexity and apply to large classes of programs. The specifications are converted to generic components by a set of rules and the generic components are input to a nonlinear sizing function which makes the final prediction. The system developed for this project predicted code sizes from the database with a bias factor of 1.06 and a fluctuation factor of 1.77, an accuracy similar to that of human experts but without their significant optimistic bias.

  3. Particle beam digital phase control system for COSY

    International Nuclear Information System (INIS)

    Schnase, A.

    1994-02-01

    Particle accelerators require that the orbit of the charged particles in the vacuum chamber is controlled to fulfil narrow limits. This is done by magnetic deflection systems and exactly adjusted rf-acceleration. Up to now the necessary control-functions were realised with analogue parts. This work describes a digital phase control system that works in real time and is used with the proton accelerator COSY. The physical design of the accelerator sets the accuracy-specifications of the revolution frequency (<1 Hz in the whole range from 400 kHz to 1.6 MHz), the phase-difference (<0.01 ), the signal-to-noise-ratio (<-60 dBc) and the update rate (<1 μs) of the parameters. In a typical operation the beam is first bunched and synchronised to the reference oscillator. After that the beam influences the rf-system with the help of charge detectors and now the rf-systems will be synchronised with the bunched beam. This control-loop is modelled and simulated with PSPICE. (orig.)

  4. Phase transitions in alloys of the Ni-Mo system

    International Nuclear Information System (INIS)

    Ustinovshikov, Y.; Shabanova, I.

    2011-01-01

    Graphical abstract: The structure of Ni-20 at.% Mo and Ni-25 at.% Mo alloys was studied by methods of TEM and XPS. It is shown that at high temperatures the tendency toward phase separation takes place in the alloys and crystalline bcc Mo particles precipitate in the liquid solution. At 900 deg. C and below, the tendency toward ordering leads to the dissolution of Mo particles and precipitation of the particles of Ni 3 Mo, Ni 2 Mo or Ni 4 Mo chemical compounds. Highlights: → 'Chemical' phase transition 'ordering-phase separation' is first discovered in alloys of the Ni-Mo system. → It is first shown that the phase separation in the alloys studied begins at temperatures above the liquidus one. → The formation of Ni 3 Mo from A1 has gone through the intervening stage of the Ni 4 Mo and Ni 2 Mo coexistence. - Abstract: The structure of Ni-20 at.% Mo and Ni-25 at.% Mo alloys heat treated at different temperatures was studied by the method of transmission electron microscopy. X-ray photoelectron spectroscopy was used to detect the sign of the chemical interaction between Ni and Mo atoms at different temperatures. It is shown that at high temperatures the tendency toward phase separation takes place. The system of additional reflections at positions {1 1/2 0} on the electron diffraction patterns testifies that the precipitation of crystalline bcc Mo particles begins in the liquid solution. At 900 deg. C and below, the tendency toward ordering leads to the precipitation of the particles of the chemical compounds. A body-centered tetragonal phase Ni 4 Mo (D1 a ) is formed in the Ni-20 at.% Mo alloy. In the Ni-25 at.% Mo alloy, the formation of the Ni 3 Mo (D0 22 ) chemical compound from the A1 solid solution has gone through the intervening stage of the Ni 4 Mo (D1 a ) and Ni 2 Mo (Pt 2 Mo) formation.

  5. Phase diagram of power law and Lennard-Jones systems: Crystal phases

    International Nuclear Information System (INIS)

    Travesset, Alex

    2014-01-01

    An extensive characterization of the low temperature phase diagram of particles interacting with power law or Lennard-Jones potentials is provided from Lattice Dynamical Theory. For power law systems, only two lattice structures are stable for certain values of the exponent (or softness) (A15, body centered cube (bcc)) and two more (face centered cubic (fcc), hexagonal close packed (hcp)) are always stable. Among them, only the fcc and bcc are equilibrium states. For Lennard-Jones systems, the equilibrium states are either hcp or fcc, with a coexistence curve in pressure and temperature that shows reentrant behavior. The hcp solid never coexists with the liquid. In all cases analyzed, for both power law and Lennard-Jones potentials, the fcc crystal has higher entropy than the hcp. The role of anharmonic terms is thoroughly analyzed and a general thermodynamic integration to account for them is proposed

  6. The Cu-Bi-Se phase system at temperatures between 300° and 750° C

    DEFF Research Database (Denmark)

    Karup-Møller, Sven

    2003-01-01

    Phase relations were determined in the Cu-Bi-Se phase system at 300, 350, 400, 450, 550, 650 and 750degreesC. Four ternary phases, phase A-D, have been synthesized. Phase A (Cu4Bi4Se9) is isotype with Cu4Bi4S9, and phase B (Cu1.7Bi4.7 Se-8) and phase C (Cu3Bi5Se9) have the same structure type as P...

  7. Sperry Low Temperature Geothermal Conversion System, Phase 1 and Phase 2. Volume 3: Systems description

    Science.gov (United States)

    Matthews, H. B.

    The major fraction of hydrothermal resources with the prospect of economic usefulness for the generation of electricity are in the 300(0)F to 425(0)F temperature range. Cost effective conversion of the geothermal energy to electricity requires new ideas to improve conversion efficiency, enhance brine flow, reduce plant costs, increase plant availability, and shorten the time between investment and return. The problems addressed are those inherent in the geothermal environment, in the binary fluid cycle, in the difficulty of efficiently converting the energy of a low temperature resource, and in geothermal economics some of these problems are explained. The energy expended by the down hole pump; the difficulty in designing reliable down hole equipment; fouling of heat exchanger surfaces by geothermal fluids; the unavailability of condenser cooling water at most geothermal sites; the large portion of the available energy used by the feed pump in a binary system; the pinch effect, a loss in available energy in transferring heat from water to an organic fluid; flow losses in fluids that carry only a small amount of useful energy to begin with; high heat exchanger costs, the lower the temperature interval of the cycle, the higher the heat exchanger costs in $/kW; the complexity and cost of the many auxiliary elements of proposed geothermal plants; and the unfortunate cash flow vs. investment curve caused by the many years of investment required to bring a field into production before any income is realized.

  8. Spectral Weighting Functions for Single-symbol Phase-noise Specifications in OFDM Systems

    NARCIS (Netherlands)

    Hoeksema, F.W.; Schiphorst, Roelof; Slump, Cornelis H.

    2003-01-01

    For the specification of phase-noise requirements for the front-end of a HiperLAN/2 system we investigated available literature on the subject. Literature differed in several aspects. One aspect is in the type of phase-noise used (Wiener phase-noise or small-angle phase noise). A Wiener phase-noise

  9. Phase Modulation Method for Control Systems of Rotary Machine Parameters

    Directory of Open Access Journals (Sweden)

    V. V. Sychev

    2014-01-01

    Full Text Available Traditionally, vibration-based diagnostics takes the main place in a large complex of technical control means of rotary machine operation. It allows us to control the onset of extreme limit states of operating construction and its elements. However, vibration-based diagnostics is incapable to provide differentiated information about the condition of particular units, type of fault and point of its occurrence.From the practical experience of optoelectronic sensors development, methods of phase coding information about the behavior of the investigated object are known. They allow us to overcome the abovementioned disadvantage of vibration-based diagnostics through the modulation of the reflected radiation from the object. This phase modulation is performed with the image analyzers, in which the modulating raster (alternating transparent and nontransparent sectors is designed so, that the carrier frequency of oscillations is absent (suppressed in frequency spectrum, and all useful information can be found in the side frequencies.Carrier frequency suppression appears for two complete turns of the modulating raster. Each time during this process oscillations have a 180° phase shift (hop relatively to the initial oscillation on the boundary of each turn. It leads to a substantial increase in signal/noise ratio and possibility to conduct high-accuracy diagnostics.The principle of the pseudo inversion is used for measurements to suppress an adverse effect of various factors in dynamic control system. For this principle the leaving and returned beams practically go on the same way with small spatial shift. This shift occurs then the leaving beam reflects from a basic surface and the reflected – from the measured surface of the object. Therefore the measurements become insensitive to any other errors of system, except relative position of system «model-object».The main advantages of such measurements are the following:- system steadiness to error

  10. Radioactive and industrial waste water collection system study, Phase I

    International Nuclear Information System (INIS)

    1993-01-01

    Phase I of the Radioactive Liquid Waste (RLW) Collection System Study has been completed, and the deliverables for this portion of the study are enclosed. The deliverables include: The Work Break-down Structure (WBS) for Phase II; The Annotated Outline for the Collection Study Report; The Process Flow Diagrams (PFD) of the RLW collection system based on current literature and knowledge; The Configuration database; The Reference Index, listing all currently held documents of the RLW collection system; The Reference Drawing Index listing all currently held, potentially applicable, drawings reviewed during the PFD development; The Regulation Identification Document for RCRA and CWA; The Regulation Database for RCRA and CWA; The Regulation Review Log, including statements justifying the non-applicability of certain regulations; Regulation Library, including the photocopied regulations with highlighted text for RCRA and CWA; The summary of RTG's waste water treatment plant design experience and associated regulations on which RTG based the design of these treatment facilities; TA-50 Influent Database; Radioactive Liquid Waste Stream Characterization Database

  11. Phase equilibria and molecular interaction studies on (naphthols + vanillin) systems

    International Nuclear Information System (INIS)

    Gupta, Preeti; Agrawal, Tanvi; Das, Shiva Saran; Singh, Nakshatra Bahadur

    2012-01-01

    Highlights: ► Phase equilibria of (naphthol + vanillin) systems have been studied for the first time. ► Eutectic type phase diagrams are obtained. ► Eutectic mixtures show nonideal behaviour. ► There is a weak molecular interaction between the components in the eutectic mixtures. ► α-Naphthol–vanillin eutectic is more stable as compared to β-naphthol–vanillin. - Abstract: Phase equilibria between (α-naphthol + vanillin) and (β-naphthol + vanillin) systems have been studied by thaw-melt method and the results show the formation of simple eutectic mixtures. Crystallization velocities of components and eutectic mixtures were determined at different stages under cooling. With the help of differential scanning calorimeter (DSC), the enthalpy of fusion of components and eutectic mixtures was determined and from the values excess thermodynamic functions viz., excess Gibbs free energy (G E ), excess entropy (S E ), excess enthalpy (H E ) of hypo-, hyper- and eutectic mixtures were calculated. Flexural strength measurements were made in order to understand the non-ideal nature of eutectics. FT-IR spectral studies indicate the formation of hydrogen bond in the eutectic mixture. Anisotropic and isotropic microstructural studies of components, hypo-, hyper- and eutectic mixtures were made. Jackson’s roughness parameter was calculated and found to be greater than 2 suggesting the faceted morphology with irregular structures. The overall results have shown that there is a weak molecular interaction between the components in the eutectic mixtures and the (α-naphthol + vanillin) eutectic is more stable as compared to the (β-naphthol + vanillin) eutectic system.

  12. Dynamic modelling for two-phase flow systems

    International Nuclear Information System (INIS)

    Guerra, M.A.

    1991-06-01

    Several models for two-phase flow have been studied, developing a thermal-hydraulic analysis code with one of these models. The program calculates, for one-dimensional cases with variable flow area, the transient behaviour of system process variables, when the boundary conditions (heat flux, flow rate, enthalpy and pressure) are functions of time. The modular structure of the code, eases the program growth. In fact, the present work is the basis for a general purpose accident and transient analysis code in nuclear reactors. Code verification has been made against RETRAN-02 results. Satisfactory results have been achieved with the present version of the code. (Author) [es

  13. Phase transformations in the titanium-niobium binary alloy system

    International Nuclear Information System (INIS)

    Moffat, D.L.

    1985-01-01

    A fundamental study of the phase transformations in the Ti-Nb binary alloy system was completed. Eight alloys in the range 20 to 70 at% Nb were investigated using transmission electron microscopy, light metallography, and x-ray diffraction. Measurements of electric resistivity and Vicker's microhardness also were performed. Emphasis was placed on the minimization of interstitial contamination in all steps of alloy fabrication and specimen preparation. In order to eliminate the effects of prior cold working, the alloys studied were recrystallized at 1000 0 C. Phase transformations were studied in alloys quenched to room temperature after recrystallization and then isothermally aged, and in those isothermally aged without a prior room temperature quench. It was found that the microstructures of the quenched 20 and 25% Nb alloys were extremely sensitive to quench rate - with a fast quench producing martensite, a slow quench, the omega phase. Microstructures of the higher niobium content alloys were much less sensitive to quench rate. The microstructures of the isothermally aged 20 and 25% Nb alloys were found to be sensitive to prior thermal history. Alloys quenched to room temperature and then aged at 400 0 C contained large omega precipitates, while those aged without an intermediate room temperature quench contained alpha precipitates

  14. BOOK REVIEW: The Geometric Phase in Quantum Systems

    Science.gov (United States)

    Pascazio, S.

    2003-12-01

    The discovery of the geometric phase is one of the most interesting and intriguing findings of the last few decades. It led to a deeper understanding of the concept of phase in quantum mechanics and motivated a surge of interest in fundamental quantum mechanical issues, disclosing unexpected applications in very diverse fields of physics. Although the key ideas underlying the existence of a purely geometrical phase had already been proposed in 1956 by Pancharatnam, it was Michael Berry who revived this issue 30 years later. The clarity of Berry's seminal paper, in 1984, was extraordinary. Research on the topic flourished at such a pace that it became difficult for non-experts to follow the many different theoretical ideas and experimental proposals which ensued. Diverse concepts in independent areas of mathematics, physics and chemistry were being applied, for what was (and can still be considered) a nascent arena for theory, experiments and technology. Although collections of papers by different authors appeared in the literature, sometimes with ample introductions, surprisingly, to the best of my knowledge, no specific and exhaustive book has ever been written on this subject. The Geometric Phase in Quantum Systems is the first thorough book on geometric phases and fills an important gap in the physical literature. Other books on the subject will undoubtedly follow. But it will take a fairly long time before other authors can cover that same variety of concepts in such a comprehensive manner. The book is enjoyable. The choice of topics presented is well balanced and appropriate. The appendices are well written, understandable and exhaustive - three rare qualities. I also find it praiseworthy that the authors decided to explicitly carry out most of the calculations, avoiding, as much as possible, the use of the joke `after a straightforward calculation, one finds...' This was one of the sentences I used to dislike most during my undergraduate studies. A student is

  15. Computation of multiphase systems with phase field models

    International Nuclear Information System (INIS)

    Badalassi, V.E.; Ceniceros, H.D.; Banerjee, S.

    2003-01-01

    Phase field models offer a systematic physical approach for investigating complex multiphase systems behaviors such as near-critical interfacial phenomena, phase separation under shear, and microstructure evolution during solidification. However, because interfaces are replaced by thin transition regions (diffuse interfaces), phase field simulations require resolution of very thin layers to capture the physics of the problems studied. This demands robust numerical methods that can efficiently achieve high resolution and accuracy, especially in three dimensions. We present here an accurate and efficient numerical method to solve the coupled Cahn-Hilliard/Navier-Stokes system, known as Model H, that constitutes a phase field model for density-matched binary fluids with variable mobility and viscosity. The numerical method is a time-split scheme that combines a novel semi-implicit discretization for the convective Cahn-Hilliard equation with an innovative application of high-resolution schemes employed for direct numerical simulations of turbulence. This new semi-implicit discretization is simple but effective since it removes the stability constraint due to the nonlinearity of the Cahn-Hilliard equation at the same cost as that of an explicit scheme. It is derived from a discretization used for diffusive problems that we further enhance to efficiently solve flow problems with variable mobility and viscosity. Moreover, we solve the Navier-Stokes equations with a robust time-discretization of the projection method that guarantees better stability properties than those for Crank-Nicolson-based projection methods. For channel geometries, the method uses a spectral discretization in the streamwise and spanwise directions and a combination of spectral and high order compact finite difference discretizations in the wall normal direction. The capabilities of the method are demonstrated with several examples including phase separation with, and without, shear in two and three

  16. Load compensation for single phase system using series active filter

    African Journals Online (AJOL)

    user

    Keywords: Active power filter (APF), current source type of harmonic load ... Single phase active filters could attract less attention than three phase due to its low ..... Generalised single-phase p-q theory for active power filtering: simulation and.

  17. Phase transitions in distributed control systems with multiplicative noise

    Science.gov (United States)

    Allegra, Nicolas; Bamieh, Bassam; Mitra, Partha; Sire, Clément

    2018-01-01

    Contemporary technological challenges often involve many degrees of freedom in a distributed or networked setting. Three aspects are notable: the variables are usually associated with the nodes of a graph with limited communication resources, hindering centralized control; the communication is subject to noise; and the number of variables can be very large. These three aspects make tools and techniques from statistical physics particularly suitable for the performance analysis of such networked systems in the limit of many variables (analogous to the thermodynamic limit in statistical physics). Perhaps not surprisingly, phase-transition like phenomena appear in these systems, where a sharp change in performance can be observed with a smooth parameter variation, with the change becoming discontinuous or singular in the limit of infinite system size. In this paper, we analyze the so called network consensus problem, prototypical of the above considerations, that has previously been analyzed mostly in the context of additive noise. We show that qualitatively new phase-transition like phenomena appear for this problem in the presence of multiplicative noise. Depending on dimensions, and on the presence or absence of a conservation law, the system performance shows a discontinuous change at a threshold value of the multiplicative noise strength. In the absence of the conservation law, and for graph spectral dimension less than two, the multiplicative noise threshold (the stability margin of the control problem) is zero. This is reminiscent of the absence of robust controllers for certain classes of centralized control problems. Although our study involves a ‘toy’ model, we believe that the qualitative features are generic, with implications for the robust stability of distributed control systems, as well as the effect of roundoff errors and communication noise on distributed algorithms.

  18. A Wearable Transcranial Doppler Ultrasound Phased Array System.

    Science.gov (United States)

    Pietrangelo, Sabino J; Lee, Hae-Seung; Sodini, Charles G

    2018-01-01

     Practical deficiencies related to conventional transcranial Doppler (TCD) sonography have restricted its use and applicability. This work seeks to mitigate several such constraints through the development of a wearable, electronically steered TCD velocimetry system, which enables noninvasive measurement of cerebral blood flow velocity (CBFV) for monitoring applications with limited operator interaction. A highly-compact, discrete prototype system was designed and experimentally validated through flow phantom and preliminary human subject testing. The prototype system incorporates a custom two-dimensional transducer array and multi-channel transceiver electronics, thereby facilitating acoustic beamformation via phased array operation. Electronic steering of acoustic energy enables algorithmic system controls to map Doppler power throughout the tissue volume of interest and localize regions of maximal flow. Multi-focal reception permits dynamic vessel position tracking and simultaneous flow velocimetry over the time-course of monitoring. Experimental flow phantom testing yielded high correlation with concurrent flowmeter recordings across the expected range of physiological flow velocities. Doppler power mapping has been validated in both flow phantom and preliminary human subject testing, resulting in average vessel location mapping times testing. A wearable prototype CBFV measurement system capable of autonomous vessel search and tracking has been presented. Although flow phantom and preliminary human validation show promise, further human subject testing is necessary to compare velocimetry data against existing commercial TCD systems. Additional human subject testing must also verify acceptable vessel search and tracking performance under a variety of subject populations and motion dynamics-such as head movement and ambulation.

  19. Classical and quantum phases of low-dimensional dipolar systems

    Energy Technology Data Exchange (ETDEWEB)

    Cartarius, Florian

    2016-09-22

    In this thesis we present a detailed study of the phase diagram of ultracold bosonic atoms confined along a tight atomic wave guide, along which they experience an optical lattice potential. In this quasi-one dimensional model we analyse the interplay between interactions and quantum fluctuations in (i) determining the non-equilibrium steady state after a quench and (ii) giving rise to novel equilibrium phases, when the interactions combine the s-wave contact interaction and the anisotropic long range dipole-dipole interactions. In detail, in the first part of the thesis we study the depinning of a gas of impenetrable bosons following the sudden switch of of the optical lattice. By means of a Bose-Fermi mapping we infer the exact quantum dynamical evolution and show that in the thermodynamic limit the system is in a non-equilibrium steady state without quasi-long range order. In the second part of the thesis, we study the effect of quantum fluctuations on the linear-zigzag instability in the ground state of ultracold dipolar bosons, as a function of the strength of the transverse confinement. We first analyse the linear-zigzag instability in the classical regime, and then use our results to develop a multi-mode Bose-Hubbard model for the system. We then develop several numerical methods, to determine the ground state.

  20. Ternary systems Sr-{Ni,Cu}-Si: Phase equilibria and crystal structure of ternary phases

    International Nuclear Information System (INIS)

    Nasir, Navida; Melnychenko-Koblyuk, Nataliya; Grytsiv, Andriy; Rogl, Peter; Giester, Gerald; Wosik, Jaroslaw; Nauer, Gerhard E.

    2010-01-01

    Phase relations were established in the Sr-poor part of the ternary systems Sr-Ni-Si (900 deg. C) and Sr-Cu-Si (800 deg. C) by light optical microscopy, electron probe microanalysis and X-ray diffraction on as cast and annealed alloys. Two new ternary compounds SrNiSi 3 (BaNiSn 3 -type) and SrNi 9-x Si 4+x (own-type) were found in the Sr-Ni-Si system along with previously reported Sr(Ni x Si 1-x ) 2 (AlB 2 -type). The crystal structure of SrNi 9-x Si 4+x (own-type, x=2.7, a=0.78998(3), c=1.1337(2) nm; space group P4/nbm) was determined from X-ray single crystal counter to be a low symmetry derivative of the cubic, parent NaZn 13 -type. At higher Si-content X-ray Rietveld refinements reveal the formation of a vacant site (□) corresponding to a formula SrNi 5.5 Si 6.5 □ 1.0 . Phase equilibria in the Sr-Cu-Si system are characterized by the compounds SrCu 2-x Si 2+x (ThCr 2 Si 2 -type), Sr(Cu x Si 1-x ) 2 (AlB 2 -type), SrCu 9-x Si 4+x (0≤x≤1.0; CeNi 8.5 Si 4.5 -type) and SrCu 13-x Si x (4≤x≤1.8; NaZn 13 -type). The latter two structure types appear within a continuous solid solution. Neither a type-I nor a type-IX clathrate compound was encountered in the Sr-{Cu,Ni}-Si systems. Structural details are furthermore given for about 14 new ternary compounds from related alloy systems with Ba. - Graphical abstract: The crystal structure of SrNi 9-x Si 4+x (own-type, x=2.7, a=0.78998(3), c=1.1337(2) nm; space group P4/nbm) was determined from X-ray single crystal counter to be a low symmetry derivative of the cubic, parent NaZn 13 -type and is related to CeNi 8.5 Si 4.5 -type.

  1. Development of Phase Lock Loop System for Synchronisation of a Hybrid System with the Grid

    Directory of Open Access Journals (Sweden)

    A. S. Abubakar

    2016-06-01

    Full Text Available Phase locked loop (PLL is an important part of the control unit of the grid connected power converter. The method of zero crossing detection (ZCD does not produce accurate phase information when grid is non-ideal. In this work, a synchronous reference frame (SRF PLL method to obtain accurate phase information when the grid voltages are unbalanced is proposed. The performances of the PLL have been verified for ideal and abnormal grid conditions such as unbalance, voltage sag, faults condition etc. Based on the results obtained, the developed PLL gives better fault ride when unbalances in the three phase input signals are overall handled well by the PLL system as it locks the two signal back within the first cycle. It also overcomes a phase jump after 5 milli-seconds from the time the fault was introduced and performs better tracking of the grid voltage and that of the renewable energy source.

  2. Development of Phase Lock Loop System for Synchronisation of a Hybrid System with the Grid

    Directory of Open Access Journals (Sweden)

    A. S. Abubakar

    2016-12-01

    Full Text Available Phase locked loop (PLL is an important part of the control unit of the grid connected power converter. The method of zero crossing detection (ZCD does not produce accurate phase information when grid is non-ideal. In this work, a synchronous reference frame (SRF PLL method to obtain accurate phase information when the grid voltages are unbalanced is proposed. The performances of the PLL have been verified for ideal and abnormal grid conditions such as unbalance, voltage sag, faults condition etc. Based on the results obtained, the developed PLL gives better fault ride when unbalances in the three phase input signals are overall handled well by the PLL system as it locks the two signal back within the first cycle. It also overcomes a phase jump after 5 milli-seconds from the time the fault was introduced and performs better tracking of the grid voltage and that of the renewable energy source.

  3. Magnetic phase transitions in low dimension quantum spin systems

    International Nuclear Information System (INIS)

    Canevet, Emmanuel

    2010-01-01

    In this PhD thesis, three low dimensional spin systems are studied by means of elastic and inelastic neutron scattering. Macroscopic measurements in the DMACuCl 3 compound indicate the coexistence of two kinds of dimers: antiferromagnetic and ferromagnetic. The magnetic structure determined by our neutron diffraction survey at H = 0 shows irrevocably the existence of these two kinds of dimers. It has been shown that the Ising-like compound BaCo 2 V 2 O 8 should be the first realization of a system in which a longitudinal spin density wave (LSDW) magnetic order occurs when a magnetic field is applied. In a first time, we have determined the magnetic structure in zero magnetic field. Then, we focused on the effect of a magnetic field on the propagation vector, showing an entrance in the LSDW phase at H c = 3.9 T. The magnetic structure refined above this critical field confirms that BaCo 2 V 2 O 8 is the first compound in which occurs a LSDW phase. In the organic compound DF 5 PNN, it has been shown that this compound is well described at low temperature by spin chains with alternating couplings. However, the crystallographic structure determined at room temperature implies that the interactions are uniform. By means of neutron diffraction, we characterized a structural transition at low temperature (T c = 450 mK) making the system evolve from C2/c space group to Pc. This transition explains the alternating behavior of the interactions. We have also evidenced a field-induced structural transition (H c = 1.1 T). Above this field, the system is back to the C2/c space group, implying that the interactions are back to uniform. We have confirmed this by studying the magnetic excitations. (author) [fr

  4. Phase modulated high density collinear holographic data storage system with phase-retrieval reference beam locking and orthogonal reference encoding.

    Science.gov (United States)

    Liu, Jinpeng; Horimai, Hideyoshi; Lin, Xiao; Huang, Yong; Tan, Xiaodi

    2018-02-19

    A novel phase modulation method for holographic data storage with phase-retrieval reference beam locking is proposed and incorporated into an amplitude-encoding collinear holographic storage system. Unlike the conventional phase retrieval method, the proposed method locks the data page and the corresponding phase-retrieval interference beam together at the same location with a sequential recording process, which eliminates piezoelectric elements, phase shift arrays and extra interference beams, making the system more compact and phase retrieval easier. To evaluate our proposed phase modulation method, we recorded and then recovered data pages with multilevel phase modulation using two spatial light modulators experimentally. For 4-level, 8-level, and 16-level phase modulation, we achieved the bit error rate (BER) of 0.3%, 1.5% and 6.6% respectively. To further improve data storage density, an orthogonal reference encoding multiplexing method at the same position of medium is also proposed and validated experimentally. We increased the code rate of pure 3/16 amplitude encoding method from 0.5 up to 1.0 and 1.5 using 4-level and 8-level phase modulation respectively.

  5. The fault monitoring and diagnosis knowledge-based system for space power systems: AMPERES, phase 1

    Science.gov (United States)

    Lee, S. C.

    1989-01-01

    The objective is to develop a real time fault monitoring and diagnosis knowledge-based system (KBS) for space power systems which can save costly operational manpower and can achieve more reliable space power system operation. The proposed KBS was developed using the Autonomously Managed Power System (AMPS) test facility currently installed at NASA Marshall Space Flight Center (MSFC), but the basic approach taken for this project could be applicable for other space power systems. The proposed KBS is entitled Autonomously Managed Power-System Extendible Real-time Expert System (AMPERES). In Phase 1 the emphasis was put on the design of the overall KBS, the identification of the basic research required, the initial performance of the research, and the development of a prototype KBS. In Phase 2, emphasis is put on the completion of the research initiated in Phase 1, and the enhancement of the prototype KBS developed in Phase 1. This enhancement is intended to achieve a working real time KBS incorporated with the NASA space power system test facilities. Three major research areas were identified and progress was made in each area. These areas are real time data acquisition and its supporting data structure; sensor value validations; development of inference scheme for effective fault monitoring and diagnosis, and its supporting knowledge representation scheme.

  6. Automatic phase control in solar power satellite systems

    Science.gov (United States)

    Lindsey, W. C.; Kantak, A. V.

    1978-01-01

    Various approaches to the problem of generating, maintaining and distributing a coherent, reference phase signal over a large area are suggested, mathematically modeled and analyzed with respect to their ability to minimize: phase build-up, beam diffusion and beam steering phase jitter, cable length, and maximize power transfer efficiency. In addition, phase control configurations are suggested which alleviate the need for layout symmetry.

  7. Nuclear plant service water system aging degradation assessment: Phase 1

    International Nuclear Information System (INIS)

    Jarrell, D.B.; Johnson, A.B. Jr.; Zimmerman, P.W.; Gore, M.L.

    1989-06-01

    The initial phase of an aging assessment of nuclear power plant service water systems (SWSs) was performed by the Pacific Northwest Laboratory to support the Nuclear Regulatory Commission Nuclear Plant Aging Research (NPAR) program. The SWS was selected for study because of its essential role in the mitigation of and recovery from accident scenarios involving the potential for core-melt. The objectives of the SWS task under the NPAR program are to identify and characterize the principal aging degradation mechanisms relevant to this system and assess their impact on operational readiness, and to provide a methodology for the mitigation of aging on the service water aspect of nuclear plant safety. The first two of these objectives have been met and are covered in this Phase 1 report. A review of available literature and data-base information indicated that motor operated valve torque switches (an electro-mechanical device) were the prime suspect in component service water systems failures. More extensive and detailed data obtained from cooperating utility maintenance records and personnel accounts contradicted this conclusion indicating that biologic and inorganic accumulation and corrosive attack of service water on component surfaces were, in fact, the primary degradation mechanisms. A review of the development of time dependent risk assessment (aging) models shows that, as yet, this methodology has not been developed to a degree where implementation is reliable. Improvements in the accuracy of failure data documentation and time dependent risk analysis methodology should yield significant gains in relating aging phenomena to probabilistic risk assessment. 23 refs., 8 figs., 10 tabs

  8. National Geoscience Data Repository System: Phase 2 final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-01

    The American Geological Institute (AGI) has completed Phase 2 of a project to establish a National Geoscience Data Repository System (NGDRS). The project`s primary objectives are to preserve geoscience data in jeopardy of being destroyed and to make that data available to those who have a need to use it in future investigations. These data are available for donation to the public as a result of the downsizing that has occurred in the major petroleum and mining companies in the US for the past decade. In recent years, these companies have consolidated domestic operations, sold many of their domestic properties and relinquished many of their leases. The scientific data associated with those properties are no longer considered to be useful assets and are consequently in danger of being lost forever. The national repository project will make many of these data available to the geoscience community for the first time. Phase 2 encompasses the establishment of standards for indexing and cataloging of geoscience data and determination of the costs of transferring data from the private sector to public-sector data repositories. Pilot projects evaluated the feasibility of the project for transfer of different data types and creation of a Web-based metadata supercatalog and browser. Also as part of the project, a national directory of geoscience data repositories was compiled to assess what data are currently available in existing facilities. The next step, Phase 3, will focus on the initiation of transfer of geoscience data from the private sector to the public domain and development of the web-based Geotrek metadata supercatalog.

  9. Phase Change Energy Storage Material Suitable for Solar Heating System

    Science.gov (United States)

    Li, Xiaohui; Li, Haihua; Zhang, Lihui; Liu, Zhenfa

    2018-01-01

    Differential scanning calorimetry (DSC) was used to investigate the thermal properties of palmitic acid, myristic acid, laurel acid and the binary composite of palmitic/laurel acid and palmitic/myristic acid. The results showed that the phase transition temperatures of the three monomers were between 46.9-65.9°C, and the latent heats were above 190 J/g, which could be used as solar energy storage material. When the mass ratio of Palmitic acid and myristic was 1:1, the eutectic mixture could be formed. The latent heat of the eutectic mixture was 186.6 J/g, the melting temperature and the solidification temperature was 50.6°C and 43.8°C respectively. The latent heat of phase change and the melting temperature had not obvious variations after 400 thermal cycles, which proved that the binary composite had good thermal stability and was suitable for solar floor radiant heating system.

  10. Rooftop PV system. Final technical progress report, Phase II

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    Under this four-year PV:BONUS Program, ECD and United Solar are developing and demonstrating two new lightweight flexible building integrated Photovoltaic (BIPV) modules specifically designed as exact replacements for conventional asphalt shingles and standing seam metal roofing. These modules can be economically and aesthetically integrated into new residential and commercial buildings, and address the even larger roofing replacement market. The modules are designed to be installed by roofing contractors without special training which minimizes the installation and balance of system costs. The modules will be fabricated from high-efficiency, multiple-junction a-Si alloy solar cells developed by ECD and United Solar. Under the Phase I Program, which ended in March 1994, we developed two different concept designs for rooftop PV modules: (1) the United Solar overlapping (asphalt shingle replacement) shingle-type modules and (2) the ECD metal roof-type modules. We also developed a plan for fabricating, testing and demonstrating these modules. Candidate demonstration sites for our rooftop PV modules were identified and preliminary engineering designs for these demonstrations were developed; a marketing study plan was also developed. The major objectives of the Phase II Program, which started in June 1994 was (1) to develop, test, and qualify these new rooftop modules; (2) to develop mechanical and electrical engineering specifications for the demonstration projects; and (3) to develop a marketing/commercialization plan.

  11. Power Based Phase-Locked Loop Under Adverse Conditions with Moving Average Filter for Single-Phase System

    Directory of Open Access Journals (Sweden)

    Menxi Xie

    2017-06-01

    Full Text Available High performance synchronization methord is citical for grid connected power converter. For single-phase system, power based phase-locked loop(pPLL uses a multiplier as phase detector(PD. As single-phase grid voltage is distorted, the phase error information contains ac disturbances oscillating at integer multiples of fundamental frequency which lead to detection error. This paper presents a new scheme based on moving average filter(MAF applied in-loop of pPLL. The signal characteristic of phase error is dissussed in detail. A predictive rule is adopted to compensate the delay induced by MAF, thus achieving fast dynamic response. In the case of frequency deviate from nomimal, estimated frequency is fed back to adjust the filter window length of MAF and buffer size of predictive rule. Simulation and experimental results show that proposed PLL achieves good performance under adverse grid conditions.

  12. Integrated thermal treatment system study. Phase 2. Addendum system A8

    International Nuclear Information System (INIS)

    Biagi, C.; Teheranian, B.; Quapp, W.J.; Schwinkendorf, W.E.

    1996-05-01

    This is an addendum to the Integrated Treatment System Study - Phase 2 Results report. This addendum describes the technology and the operation of System A-8, Rotary Kiln, Air Combustion Gas, Dry-Wet APC, and Grout Stabilization. A process flow diagram, functional allocation diagrams, and plan views and perspective views for this system are attached. Detailed cost information for this subsystem is reported in Appendix A of this addendum

  13. The application and design of distributed control system in reactor shutdown system of Qinshan phase III

    International Nuclear Information System (INIS)

    Su Guoquan; Liu Wangtian; Yu Yijun; Xiong Weihua

    2006-03-01

    The design, commissioning and running of the reactor trip parameter monitoring system used in Qinshan Phase III are introduced. The applying technology of Distributed Control System realized trip parameter monitoring and realized the function of trip parameters quick data acquisitioning, transferring, saving, alarm, query. The applying of trip parameters monitoring system improved the abilities of plant status monitoring and event analyzing, and increased the security and economy of nuclear power plant. (authors)

  14. HESTIA Phase I Test Results: The Air Revitalization System

    Science.gov (United States)

    Wright, Sarah E.; Hansen, Scott W.

    2016-01-01

    In any human spaceflight mission, a number of Environmental Control & Life Support System (ECLSS) technologies work together to provide the conditions astronauts need to live healthily, productively, and comfortably in space. In a long-duration mission, many of these ECLSS technologies may use materials supplied by In-Situ Resource Utilization (ISRU), introducing more interactions between systems. The Human Exploration Spacecraft Test-bed for Integration & Advancement (HESTIA) Project aims to create a test-bed to evaluate ECLSS and ISRU technologies and how they interact in a high-fidelity, closed-loop, human-rated analog habitat. Air purity and conditioning are essential components within any ECLSS and for HESTIA's first test they were achieved with the Air Revitalization System (ARS) described below. The ARS provided four essential functions to the test-bed chamber: cooling the air, removing humidity from the air, removing trace contaminants, and scrubbing carbon dioxide (CO2) from the air. In this case, the oxygen supply function was provided by ISRU. In the current configuration, the ARS is a collection of different subsystems. A fan circulates the air, while a condensing heat exchanger (CHX) pulls humidity out of the air. A Trace Contaminant Removal System (TCRS) filters the air of potentially harmful contaminants. Lastly, a Reactive Plastic Lithium Hydroxide (RP-LiOH) unit removes CO2 from the breathing air. During the HESTIA Phase I test in September 2015, the ARS and its individual components each functioned as expected, although further analysis is underway. During the Phase I testing and in prior bench-top tests, the energy balance of heat removed by the CHX was not equal to the cooling it received. This indicated possible instrument error and therefore recalibration of the instruments and follow-up testing is planned in 2016 to address the issue. The ARS was tested in conjunction with two other systems: the Human Metabolic Simulator (HMS) and the

  15. Two-phase flow heat transfer in nuclear reactor systems

    International Nuclear Information System (INIS)

    Koncar, Bostjan; Krepper, Eckhard; Bestion, Dominique; Song, Chul-Hwa; Hassan, Yassin A.

    2013-01-01

    Complete text of publication follows: Heat transfer and phase change phenomena in two-phase flows are often encountered in nuclear reactor systems and are therefore of paramount importance for their optimal design and safe operation.The complex phenomena observed especially during transient operation of nuclear reactor systems necessitate extensive theoretical and experimental investigations. This special issue brings seven research articles of high quality. Though small in number, they cover a wide range of topics, presenting high complexity and diversity of heat transfer phenomena in two-phase flow. In the last decades a vast amount of research has been devoted to theoretical work and computational simulations, yet the experimental work remains indispensable for understanding of two-phase flow phenomena and for model validation purposes. This is reflected also in this issue, where only one article is purely experimental, while three of them deal with theoretical modelling and the remaining three with numerical simulations. The experimental investigation of the critical heat flux (CHF) phenomena by means of photographic study is presented in the paper of J. Park et al. They have used a high-speed camera system to observe the transient boiling characteristics on a thin horizontal cylinder submerged in a pool of water or highly wetting liquid. Experiments show that the initial boiling process is strongly affected by the properties and wettability of the liquid. The authors have stressed the importance of the local scale observation leading to better understanding of the transient CHF phenomena. In the article of G. Espinosa-Paredes et al. a theoretical work concerning the derivation of transport equations for two-phase flow is presented. The author proposes a novel approach based on derivation of nonlocal volume averaged equations which contain new terms related to nonlocal transport effects. These non-local terms act as coupling elements between the phenomena

  16. Regenerable Air Purification System for Gas-Phase Contaminant Control

    Science.gov (United States)

    Constantinescu, Ileana C.; Finn, John E.; LeVan, M. Douglas; Lung, Bernadette (Technical Monitor)

    2000-01-01

    Tests of a pre-prototype regenerable air purification system (RAPS) that uses water vapor to displace adsorbed contaminants from an adsorbent column have been performed at NASA Ames Research Center. A unit based on this design can be used for removing trace gas-phase contaminants from spacecraft cabin air or from polluted process streams including incinerator exhaust. During the normal operation mode, contaminants are removed from the air on the column. Regeneration of the column is performed on-line. During regeneration, contaminants are displaced and destroyed inside the closed oxidation loop. In this presentation we discuss initial experimental results for the performance of RAPS in the removal and treatment of several important spacecraft contaminant species from air.

  17. (Liquid + liquid) phase behavior for systems containing (aromatic + TBA + methylcyclohexane)

    International Nuclear Information System (INIS)

    Ghanadzadeh, H.; Ghanadzadeh, A.

    2004-01-01

    The determination region of solubility of TBA (tert-butanol) with representative compounds of the gasoline was investigated experimentally at temperature of 298.2 K. Type 1 (liquid + liquid) phase diagrams were obtained for (methylcyclohexane + TBA + aromatic compounds). These results were correlated simultaneously by the UNIQUAC model. The values of the interaction parameters between each pair of components in the systems were obtained for the UNIQUAC model using the experimental result. The root mean square deviation (RMSD) between the observed and calculated mole percents was 1.88 for (methylcyclohexane + TBA + benzene), 2.45 for (methylcyclohexane + TBA + toluene) and 2.86 for (methylcyclohexane + TBA + ethylbenzene). The mutual solubility of methylcyclohexane and aromatic compounds (e.g., benzene toluene and ethylbenzene (BTE)) was also investigated by the addition of TBA at temperature of 298.2 K

  18. Phases of polymer systems in solution studied via molecular dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Joshua Allen [Iowa State Univ., Ames, IA (United States)

    2009-05-01

    Polymers are amazingly versatile molecules with a tremendous range of applications. Our lives would be very different without them. There would be no multitudes of plastic encased electronic gizmos, no latex paint on the walls and no rubber tires, just to name a few of the many commonplace polymer materials. In fact, life as we know it wouldn’t exist without polymers as two of the most essential types of molecules central to cellular life, Proteins and DNA, are both polymers! [1] With their wide range of application to a variety of uses, polymers are still a very active field in basic research. Of particular current interest is the idea of combining polymers with inorganic particles to form novel composite materials. [2] As computers are becoming faster, they are becoming all the more powerful tools for modeling and simulating real systems. With recent advances in computing on graphics processing units (GPUs) [3–7], questions can now be answered via simulation that could not even be asked before. This thesis focuses on the use of computer simulations to model novel polymerinorganic composite systems in order to predict what possible phases can form and under what conditions. The goal is to provide some direction for future experiments and to gain a deeper understanding of the fundamental physics involved. Along the way, there are some interesting and essential side-tracks in the areas of equilibrating complicated phases and accelerating the available computer power with GPU computing, both of which are necessary steps to enable the study of polymer nanocomposites.

  19. Enhancement of Iris Recognition System Based on Phase Only Correlation

    Directory of Open Access Journals (Sweden)

    Nuriza Pramita

    2011-08-01

    Full Text Available Iris recognition system is one of biometric based recognition/identification systems. Numerous techniques have been implemented to achieve a good recognition rate, including the ones based on Phase Only Correlation (POC. Significant and higher correlation peaks suggest that the system recognizes iris images of the same subject (person, while lower and unsignificant peaks correspond to recognition of those of difference subjects. Current POC methods have not investigated minimum iris point that can be used to achieve higher correlation peaks. This paper proposed a method that used only one-fourth of full normalized iris size to achieve higher (or at least the same recognition rate. Simulation on CASIA version 1.0 iris image database showed that averaged recognition rate of the proposed method achieved 67%, higher than that of using one-half (56% and full (53% iris point. Furthermore, all (100% POC peak values of the proposed method was higher than that of the method with full iris points.

  20. FPGA-based prototype storage system with phase change memory

    Science.gov (United States)

    Li, Gezi; Chen, Xiaogang; Chen, Bomy; Li, Shunfen; Zhou, Mi; Han, Wenbing; Song, Zhitang

    2016-10-01

    With the ever-increasing amount of data being stored via social media, mobile telephony base stations, and network devices etc. the database systems face severe bandwidth bottlenecks when moving vast amounts of data from storage to the processing nodes. At the same time, Storage Class Memory (SCM) technologies such as Phase Change Memory (PCM) with unique features like fast read access, high density, non-volatility, byte-addressability, positive response to increasing temperature, superior scalability, and zero standby leakage have changed the landscape of modern computing and storage systems. In such a scenario, we present a storage system called FLEET which can off-load partial or whole SQL queries to the storage engine from CPU. FLEET uses an FPGA rather than conventional CPUs to implement the off-load engine due to its highly parallel nature. We have implemented an initial prototype of FLEET with PCM-based storage. The results demonstrate that significant performance and CPU utilization gains can be achieved by pushing selected query processing components inside in PCM-based storage.

  1. Carrier phase synchronization system for improved amplitude modulation and television broadcast reception

    Science.gov (United States)

    Smith, Stephen F [Loudon, TN; Moore, James A [Powell, TN

    2009-09-08

    Systems and methods are described for carrier phase synchronization for improved AM and TV broadcast reception. A method includes synchronizing the phase of a carrier frequency of a broadcast signal with the phase of a remote reference frequency. An apparatus includes a receiver to detect the phase of a reference signal; a phase comparator coupled to the reference signal-phase receiver; a voltage controlled oscillator coupled to the phase comparator; and a phase-controlled radio frequency output coupled to the voltage controlled oscillator.

  2. Lifshitz-Slyozov kinetics of a nonconserved system that separates into phases of different density

    DEFF Research Database (Denmark)

    Mouritsen, Ole G.; Shah, Peter Jivan; Andersen, Jørgen Vitting

    1990-01-01

    Computer-simulation techniques are applied to analyze the late-stage ordering kinetics of a two-dimensional annealed dilute Ising model quenched into regions of its phase diagram that involve phase separation of phases with different densities. The order parameter of the model is a nonconserved...... of the phase-separation kinetics in O/W(110) systems at high coverage....

  3. Ultrafast Phase Comparator for Phase-Locked Loop-Based Optoelectronic Clock Recovery Systems

    DEFF Research Database (Denmark)

    Gomez-Agis, F.; Oxenløwe, Leif Katsuo; Kurimura, S.

    2009-01-01

    The authors report on a novel application of a chi((2)) nonlinear optical device as an ultrafast phase comparator, an essential element that allows an optoelectronic phase-locked loop to perform clock recovery of ultrahigh-speed optical time-division multiplexed (OTDM) signals. Particular interest...... is devoted to a quasi-phase-matching adhered-ridge-waveguide periodically poled lithium niobate (PPLN) device, which shows a sufficient high temporal resolution to resolve a 640 Gbits OTDM signal....

  4. Development of phase lock loop system for synchronisation of a ...

    African Journals Online (AJOL)

    Phase locked loop (PLL) is an important part of the control unit of the grid connected power converter. The method of zero crossing detection (ZCD) does not produce accurate phase information when grid is non-ideal. In this work, a synchronous reference frame (SRF) PLL method to obtain accurate phase information when ...

  5. Multifragmentation of heavy systems: partitions and phase transition signals; Multifragmentation de systemes lourds: partitions et signaux de transition de phases

    Energy Technology Data Exchange (ETDEWEB)

    Bonnet, E

    2006-09-15

    This work studies mononuclear systems produced in heavy ion collisions with large (peripheral: Au+Au) and small (central: Xe+Sn et Gd+U) impact parameters. These two classes of collisions need specific selections in order to isolate sources in thermal equilibrium (quasi-projectiles and quasi-fusion sources). We perform analyses on the statistical ensembles of events obtained after those selections to evidence phase transition signatures. First, a bimodal behaviour of the biggest fragment (Z{sub 1}) distribution, in peripheral collisions, is related to an order parameter using a renormalisation with an equiprobable excitation energy (E{sup *}) distribution constraint. A comparison with a canonical ensemble gives us information on the coexistence region location. Then, we compare static and dynamical properties of fragments produced by these sources in peripheral and central collisions. Differences on fragment multiplicities and charge asymmetry of partitions are observed. They find their origins in the presence or not of a velocity field mostly related to collective radial expansion during fragment formation. Analyses of the signal related to abnormal fluctuations of configurational energies and of the fossil signal related to spinodal decomposition for Au quasi-projectiles are performed to establish a link with the same signals already observed for central collisions. Finally, the location of events of the two types of sources in the E{sup *} - Z{sub 1} plane, are compared with a phase diagram, particularly the boundaries of the coexistence region deduced from the previous signals. (author)

  6. A parametric LTR solution for discrete-time systems

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Jannerup, Ole Erik

    1989-01-01

    A parametric LTR (loop transfer recovery) solution for discrete-time compensators incorporating filtering observers which achieve exact recovery is presented for both minimum- and non-minimum-phase systems. First the recovery error, which defines the difference between the target loop transfer...... and the full loop transfer function, is manipulated into a general form involving the target loop transfer matrix and the fundamental recovery matrix. A parametric LTR solution based on the recovery matrix is developed. It is shown that the LQR/LTR (linear quadratic Gaussian/loop transfer recovery) solution...

  7. System for recording and displaying two-phase flow topographies

    International Nuclear Information System (INIS)

    Cary, C.N.; Block, J.A.

    1979-01-01

    A system of hardware and software has been developed and used to record and display in various forms details of the countercurrent flow topographies occurring in a scaled Pressurized Water Reactor downcomer annulus. An array of 288 conductivity sensors was mounted in a 1/15 scale PWR annulus. At each moment in time, the state of each probe indicates the presence or absence of water in this immediate vicinity. An electronic data acquisition system records the states of all probes 108 times per second on magnetic tape; software routines retrieve the data and reconstruct visual analogs of the flow topographies. The instantaneous two-phase state of the annulus at each instant can be displayed on a hard copy plotter or on a CRT screen. By synchronizing a camera drive with the CRT display, 16mm films have been made recreating the flow process at full speed and at various slow motion rates. All data obtained are stored in computer files in numerical form and can be subjected to various types of quantitative analysis to assist in advanced code development and verification

  8. Brayton Isotope Power System. Phase I. (Ground demonstration system) Configuration Control Document (CCD)

    International Nuclear Information System (INIS)

    1976-01-01

    The configuration control document (CCD) defines the BIPS-GDS configuration. The GDS configuration is similar to a conceptual flight system design, referred to as the BIPS-FS, which is discussed in App. I. The BIPS is being developed by ERDA as a 500 to 2000 W(e), 7-y life, space power system utilizing a closed Brayton cycle gas turbine engine to convert thermal energy (from an isotope heat source) to electrical energy at a net efficiency exceeding 25 percent. The CCD relates to Phase I of an ERDA Program to qualify a dynamic system for launch in the early 1980's. Phase I is a 35-month effort to provide an FS conceptual design and GDS design, fabrication, and test. The baseline is a 7-year life, 450-pound, 4800 W(t), 1300 W(e) system which will use two multihundred watt (MHW) isotope heat sources being developed

  9. Enhanced Phase-Shifted Current Control for Harmonic Cancellation in Three-Phase Multiple Adjustable Speed Drive Systems

    DEFF Research Database (Denmark)

    Yang, Yongheng; Davari, Pooya; Zare, Firuz

    2017-01-01

    A phase-shifted current control can be employed to mitigate certain harmonics induced by the Diode Rectifiers (DR) and Silicon-Controlled Rectifiers (SCR) as the front-ends of multiple parallel Adjustable Speed Drive (ASD) systems. However, the effectiveness of the phase-shifted control relies...... on the loading condition of each drive unit as well as the number of drives in parallel. In order to enhance the harmonic cancellation by means of the phase-shifted current control, the currents drawn by the rectifiers should be maintained almost at the same level. Thus, this paper firstly analyzes the impact...... of unequal loading among the parallel drives, and a scheme to enhance the performance is introduced to improve the quality of the total grid current, where partial loading operation should be enabled. Simulation and experimental case studies on multidrive systems have demonstrated that the enhanced phase...

  10. Phase transitions, scaling and renormalisation in nonequilibrium systems

    International Nuclear Information System (INIS)

    Hanney, T.E.

    2002-01-01

    Nonequilibrium phase transitions and critical phenomena in simple lattice-based interacting particle models are considered. Specific models of interest are exclusion models in low dimensions, with particular reference to the asymmetric simple exclusion process (ASEP) which provides a testbed for many of the calculations. The aim of the thesis is to devise approximate scaling techniques for such models which account for fluctuations and which are more widely applicable than methods pursuing an exact solution. Scaling techniques which have been applied to models described by a linear equation of motion are extended to the case where the equation of motion is nonlinear. These methods capture the dynamic transition in the ASEP but fail to properly account for the nonlinearity in their predictions for the dynamic exponent, z. A new and widely applicable real space renormalisation group procedure is developed. It provides a direct and transparent scaling method to extract universal and non-universal properties of the steady state and dynamic critical behaviour in the boundary-driven ASEP in one dimension. In particular, we obtain a flow diagram for the problem from which we can interpret all the qualitative features of the (exactly known) steady state phase diagram and which predicts the exact value for the critical point. Further, the dynamic scaling is consistent with a crossover between diflusive behaviour near the zero current fixed point and z = 3/2 dynamics at the critical fixed point. Extensions to include disorder, to higher dimensions, and to other models are all possible using the method. Using the mapping between the Master equation and the Schroedinger equation in imaginary time, this scaling procedure is rephrased as a new blocking for quantum-spin systems. Existing methods of real space renormalisation for quantum-spin systems are applied to a variety of previously unconsidered exclusion models. In particular, it is shown how such techniques can be applied

  11. A Fuzzy Logic Based Three phase Inverter with Single DC Source for Grid Connected PV System Employing Three Phase Transformer

    OpenAIRE

    Mani, venkatesan; Ramachandran, Rajeswari; N, Deverajan

    2016-01-01

    A fuzzy based three phase inverter with single DC source for grid connected photo voltaic (PV) system employing three phase transformer is presented in this paper. Space Vector Pulse Width Modulation (SVPWM) control scheme is effectively used to generate the appropriate switching sequences to the inverter switches. The intend of the fuzzy logic approach is to meet high quality output, fast response and high robustness. Finally Total Harmonics Distortion (THD) generated by the inverter is comp...

  12. Application of Ab Initio Electronic Structure Calculations in Construction of Phase Diagrams of Metallic Systems with Complex Phases

    Czech Academy of Sciences Publication Activity Database

    Šob, Mojmír; Kroupa, Aleš; Pavlů, Jana; Vřešťál, Jan

    2009-01-01

    Roč. 150, č. 1 (2009), s. 1-28 ISSN 1012-0394 R&D Projects: GA MŠk OC 147; GA ČR GA106/07/1078 Institutional research plan: CEZ:AV0Z20410507 Keywords : Ab initio calculations * CALPHAD method * Laves phases * sigma phase * ternary systems * super-austenitic steels Subject RIV: BM - Solid Matter Physics ; Magnetism

  13. High phase noise tolerant pilot-tone-aided DP-QPSK optical communication systems

    DEFF Research Database (Denmark)

    Zhang, Xu; Pang, Xiaodan; Deng, Lei

    2012-01-01

    In this paper we experimentally demonstrate a novel, high phase-noise tolerant, optical dual polarization (DP) quadrature phase-shift keying (QPSK) communication system based on pilot-tone-aided phase noise cancellation (PNC) algorithm. Vertical cavity surface emitting lasers (VCSELs) with approx......In this paper we experimentally demonstrate a novel, high phase-noise tolerant, optical dual polarization (DP) quadrature phase-shift keying (QPSK) communication system based on pilot-tone-aided phase noise cancellation (PNC) algorithm. Vertical cavity surface emitting lasers (VCSELs...

  14. Bioconversion of apigenin-7-O-β-glucoside in aqueous two-phase system

    Directory of Open Access Journals (Sweden)

    Ilić Sanja M.

    2005-01-01

    Full Text Available The study is concerned with the conversion of apigenin-7-O-β-glucoside into apigenin in polyethylene glycol 6000 / dextran 20000 aqueous two-phase system by β-glucosidase. Apigenin was separated from apigenin-7-O-β-glucoside and β-glucosidase by their partition into opposite phases. In 14% PEG / 22.5% DEX aqueous two-phase system obtained yield of apigenin in top phase was 108%.

  15. Magnetic properties of anyonic systems in a normal phase

    International Nuclear Information System (INIS)

    Aronov, I.E.; Naftulin, S.A.

    1992-08-01

    We apply the concept of fractional statistics to the two-dimensional conductors. The effective Lagrangian of an external magnetic field in anyon medium at finite temperature and density is presented. The diamagnetic response to the external field is studied at temperatures above T c (i.e. in the normal phase) for various values of external parameters. Oscillations of both thermodynamic (the de Haas - van Alphen effect) and kinetic (the Shubnikov - de Haas effect) quantities are re-examined. Numerous peculiarities arise from the fact that anyon systems possess a non-zero ''statistical'' flux Φ (which is known to be a manifestation of the spontaneous parity breakdown). The cyclotron resonance is suggested as a direct test on possible parity violation (which is the key point of anyonics). The cyclotron mass dependences on external parameters reported in a series of experimental articles (H. Kublbeck and J.P. Kotthaus, Phys. Rev. Lett. 35, 1019 (1975); G. Abstreiter, J.P. Kotthaus, J.F. Koch and G. Dorda, Phys. Rev. B14, 2480 (1976)) may be attributed to an unusual behaviour or magnetic permeability in anyon medium. (author). 20 refs, 2 figs

  16. Phase transition in vortex system in Bi2212:Pb monocrystal

    CERN Document Server

    Uspenskaya, L S; Rakhmanov, A L

    2002-01-01

    Penetration of the magnetic flux into the (Bi sub 0 sub . sub 8 sub 4 Pb sub 0 sub . sub 1 sub 6) sub 2 sub . sub 2 Sr sub 2 CaCu sub 2 O sub 8 high-temperature superconductor monocrystal is studied thorough the magnetooptical method in the crossed magnetic fields. It is shown that the magnetic flux penetration in the low-temperature areas is anisotropic: it moves primarily along the magnetic field, applied in the sample plane, and this anisotropy grows with the temperature growth. At the temperature of T sub m = 54 +- 2 K there takes place sharp change in the character of the magnetic field penetration into the superconductor, whereby the direction of the flux motion discontinues to be dependent on the direction and value of the magnetic field applied in the sample plane. This effect is interpreted within the frames of representations on the phase transition in the vortex system connected with a sharp decrease in the correlations of the vortex position in the different CuO-planes

  17. ISOBUTANOL FROM SYNGAS IN A THREE PHASE SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Peter Tijrn

    2002-12-29

    With growing interest in oxygenates as octane booster for automotive fuels, various synthesis routes for these chemicals are being investigated. Among others, alternative routes to isobutene, the C4-components in MTBE-synthesis are under investigation. A promising path to isobutene is the heterogeneously catalyzed CO-hydrogenation to isobutanol with following dehydration (Fig. 1). As shown by thermodynamical studies, the heterogeneously catalyzed CO-hydrogenation to isobutanol is not expected to experience any thermodynamic constraints. However, heterogeneous hydrogenation of CO is a very exothermic process, a problem which can only be partly solved when being conducted in a plug flow reactor. When carried out in reaction vessels with moving catalyst bed (e.g. three phase stirred tank), heat transfer problems can be resolved, along with additional benefits connected with this reactor type. Several heterogeneous catalytic systems have been under investigation for their capability of isobutanol synthesis from syngas. Most promising catalysts for an active and selective isobutanol synthesis from CO are modified high temperature methanol catalysts.

  18. Waste Feed Delivery System Phase 1 Preliminary RAM Analysis

    International Nuclear Information System (INIS)

    DYKES, A.A.

    2000-01-01

    This report presents the updated results of the preliminary reliability, availability, and maintainability (RAM) analysis of selected waste feed delivery (WFD) operations to be performed by the Tank Farm Contractor (TFC) during Phase I activities in support of the Waste Treatment and Immobilization Plant (WTP). For planning purposes, waste feed tanks are being divided into five classes in accordance with the type of waste in each tank and the activities required to retrieve, qualify, and transfer waste feed. This report reflects the baseline design and operating concept, as of the beginning of Fiscal Year 2000, for the delivery of feed from three of these classes, represented by source tanks 241-AN-102, 241-AZ-101 and 241-AN-105. The preliminary RAM analysis quantifies the potential schedule delay associated with operations and maintenance (OBM) field activities needed to accomplish these operations. The RAM analysis is preliminary because the system design, process definition, and activity planning are in a state of evolution. The results are being used to support the continuing development of an O and M Concept tailored to the unique requirements of the WFD Program, which is being documented in various volumes of the Waste Feed Delivery Technical Basis (Carlson. 1999, Rasmussen 1999, and Orme 2000). The waste feed provided to the WTP must: (1) meet limits for chemical and radioactive constituents based on pre-established compositional envelopes (i.e., feed quality); (2) be in acceptable quantities within a prescribed sequence to meet feed quantities; and (3) meet schedule requirements (i.e., feed timing). In the absence of new criteria related to acceptable schedule performance due to the termination of the TWRS Privatization Contract, the original criteria from the Tank Waste Remediation System (77443s) Privatization Contract (DOE 1998) will continue to be used for this analysis

  19. Caltrans WeatherShare Phase II System: An Application of Systems and Software Engineering Process to Project Development

    Science.gov (United States)

    2009-08-25

    In cooperation with the California Department of Transportation, Montana State University's Western Transportation Institute has developed the WeatherShare Phase II system by applying Systems Engineering and Software Engineering processes. The system...

  20. Automatic carrier acquisition system for phase-lock-loop receivers

    Science.gov (United States)

    Bunce, R. C.

    1973-01-01

    Programmable oscillator and zero-beat detector acquires phase-lock of carrier by frequency scanning. Generation of high-level dc pulse at instant of zero crossing provides positive trigger for decision gate to stop search and close loop for phase-coherent tracking.

  1. Stability of Laves Phases in the Cr Zr System

    Czech Academy of Sciences Publication Activity Database

    Pavlů, Jana; Vřešťál, Jan; Šob, Mojmír

    2009-01-01

    Roč. 33, č. 2 (2009), s. 382-387 ISSN 0364-5916 R&D Projects: GA ČR GA106/07/1078 Institutional research plan: CEZ:AV0Z20410507 Keywords : ab initio calculations * Laves phases * phase diagrams Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.904, year: 2009

  2. Phase diagram of a symmetric electron–hole bilayer system: a variational Monte Carlo study

    Science.gov (United States)

    Sharma, Rajesh O.; Saini, L. K.; Prasad Bahuguna, Bhagwati

    2018-05-01

    We study the phase diagram of a symmetric electron–hole bilayer system at absolute zero temperature and in zero magnetic field within the quantum Monte Carlo approach. In particular, we conduct variational Monte Carlo simulations for various phases, i.e. the paramagnetic fluid phase, the ferromagnetic fluid phase, the anti-ferromagnetic Wigner crystal phase, the ferromagnetic Wigner crystal phase and the excitonic phase, to estimate the ground-state energy at different values of in-layer density and inter-layer spacing. Slater–Jastrow style trial wave functions, with single-particle orbitals appropriate for different phases, are used to construct the phase diagram in the (r s , d) plane by finding the relative stability of trial wave functions. At very small layer separations, we find that the fluid phases are stable, with the paramagnetic fluid phase being particularly stable at and the ferromagnetic fluid phase being particularly stable at . As the layer spacing increases, we first find that there is a phase transition from the ferromagnetic fluid phase to the ferromagnetic Wigner crystal phase when d reaches 0.4 a.u. at r s   =  20, and before there is a return to the ferromagnetic fluid phase when d approaches 1 a.u. However, for r s   Wigner crystal is stable over the considered range of r s and d. We also find that as r s increases, the critical layer separations for Wigner crystallization increase.

  3. Dilution Ratios for HB Line Phase I Eductor System

    International Nuclear Information System (INIS)

    Steimke, J.L.

    2002-01-01

    HB Line Phase I product transfer includes an eductor which transfers liquid from Product Hold Tank (PHT) RT-33 or RT-34 to Tank 11.1. The eductor also dilutes the liquid from the PHT with eductant. Dilution must be reliably controlled because of criticality concerns with H Canyon Tanks. The eductor system, which contains a 1 inch Model 264 Schutte and Koerting eductor, was previously modeled [1] in 1998 and dilution ratios were calculated for different flow restrictors, eductant pressures and densities for the eductant and the contents of the PHT. The previous calculation was performed using spreadsheet software no longer supported at SRS. For the previous work dilution ratio was defined as the volume of eductant consumed divided by volume of PHT contents transferred. Since 1998 HB Line Engineering has changed the definition of dilution ratio to the total volume of liquid, eductant consumed plus the volume of PHT liquid transferred, divided by the volume of PHT liquid transferred. The 1998 base case calculation was for a restrictor diameter of 0.334 inches, an eductant supply pressure of 15 psig, full PHT, an eductant specific gravity of 1.385 and a PHT density of 1.015. The base case dilution ratio calculated in 1998 using the current definition was 3.52. After accounting for uncertainty the minimum dilution ratio decreased to 3.23. In 2001 HB Line Engineering requested that the calculation be repeated for a manganous nitrate solution eductant and also a process water eductant. The other conditions were the same as for the 1998 calculation. The objective of this report is to document the calculations and the results

  4. The analysis of magnesium oxide hydration in three-phase reaction system

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Xiaojia; Guo, Lin; Chen, Chen; Liu, Quan; Li, Tie; Zhu, Yimin, E-mail: ntp@dlmu.edu.cn

    2014-05-01

    In order to investigate the magnesium oxide hydration process in gas–liquid–solid (three-phase) reaction system, magnesium hydroxide was prepared by magnesium oxide hydration in liquid–solid (two-phase) and three-phase reaction systems. A semi-empirical model and the classical shrinking core model were used to fit the experimental data. The fitting result shows that both models describe well the hydration process of three-phase system, while only the semi-empirical model right for the hydration process of two-phase system. The characterization of the hydration product using X-Ray diffraction (XRD) and scanning electron microscope (SEM) was performed. The XRD and SEM show hydration process in the two-phase system follows common dissolution/precipitation mechanism. While in the three-phase system, the hydration process undergo MgO dissolution, Mg(OH){sub 2} precipitation, Mg(OH){sub 2} peeling off from MgO particle and leaving behind fresh MgO surface. - Graphical abstract: There was existence of a peeling-off process in the gas–liquid–solid (three-phase) MgO hydration system. - Highlights: • Magnesium oxide hydration in gas–liquid–solid system was investigated. • The experimental data in three-phase system could be fitted well by two models. • The morphology analysis suggested that there was existence of a peel-off process.

  5. Composite Overwrapped Pressure Vessels (COPV) Monitoring System Using Fiber, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Intelligent Fiber Optic Systems Corporation (IFOS) proposes, in this Phase 1 SBIR project, to demonstrate the feasibility of innovations based on an...

  6. Phase-ambiguity resolution for QPSK modulation systems. Part 2: A method to resolve offset QPSK

    Science.gov (United States)

    Nguyen, Tien Manh

    1989-01-01

    Part 2 presents a new method to resolve the phase-ambiguity for Offset QPSK modulation systems. When an Offset Quaternary Phase-Shift-Keyed (OQPSK) communications link is utilized, the phase ambiguity of the reference carrier must be resolved. At the transmitter, two different unique words are separately modulated onto the quadrature carriers. At the receiver, the recovered carrier may have one of four possible phases, 0, 90, 180, or 270 degrees, referenced to the nominally correct phase. The IF portion of the channel may cause a phase-sense reversal, i.e., a reversal in the direction of phase rotation for a specified bit pattern. Hence, eight possible phase relationships (the so-called eight ambiguous phase conditions) between input and output of the demodulator must be resolved. Using the In-phase (I)/Quadrature (Q) channel reversal correcting property of an OQPSK Costas loop with integrated symbol synchronization, four ambiguous phase conditions are eliminated. Thus, only four possible ambiguous phase conditions remain. The errors caused by the remaining ambiguous phase conditions can be corrected by monitoring and detecting the polarity of the two unique words. The correction of the unique word polarities results in the complete phase-ambiguity resolution for the OQPSK system.

  7. Instantaneous Power Compensation in Three-Phase Systems by Using p-q-r Theory

    DEFF Research Database (Denmark)

    Kim, Hyosung; Blaabjerg, Frede; Bak-Jensen, Birgitte

    2002-01-01

    Three linearly independent instantaneous powers have been defined in the time domain in three-phase four-wire systems with the use of p-q-r theory. Any three-phase circuit can be transformed into three single-phase circuits by the p-q-r transformation Thus the instantaneous powers in any three...

  8. A Study of Phase Composition and Structure of Alloys of the Al - Mg - Si - Fe System

    Science.gov (United States)

    Mailybaeva, A. D.; Zolotorevskii, V. S.; Smagulov, D. U.; Islamkulov, K. M.

    2017-03-01

    The Thermo-Calc software is used to compute the phase transformations occurring during cooling of alloys. Polythermal and isothermal sections of the phase diagram of the Al - Mg - Si - Fe system are plotted. The phase composition and the structure of aluminum alloys in cast condition and after a heat treatment are studied experimentally.

  9. Phase Change Permeation Technology for Environmental Control & Life Support Systems

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA is evaluating Dutyion™, a phase change permeation membrane technology developed by Design Technology and Irrigation (DTI), for use in future advanced life...

  10. Passive Wireless SAW Humidity Sensors and System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Phase I demonstrated the technical feasibility of creating surface acoustic wave (SAW) based humidity sensors that respond rapidly (under 0.5 second) and reversibly...

  11. Novel Instrumentation for Rocket Propulsion Systems, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of the proposed SBIR Phase II program is to develop, deploy and deliver novel laser-based instruments that provide rapid, in situ, simultaneous...

  12. Structural Integrity Inspection and Visualization System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Based on the successful feasibility demonstration in Phase I, Physical Optics Corporation (POC) proposes to continue the development of a novel Structural Integrity...

  13. Quantum and thermal phase escape in extended Josephson systems

    International Nuclear Information System (INIS)

    Kemp, A.

    2006-01-01

    In this work I examine phase escape in long annular Josephson tunnel junctions. The sine-Gordon equation governs the dynamics of the phase variable along the junction. This equation supports topological soliton solutions, which correspond to quanta of magnetic flux trapped in the junction barrier. For such Josephson vortices an effective potential is formed by an external magnetic field, while a bias current acts as a driving force. Both together form a metastable potential well, which the vortex is trapped in. When the driving force exceeds the pinning force of the potential, the vortex escapes and the junction switches to the voltage state. At a finite temperature the driving force fluctuates. If the junction's energy scale is small, the phase variable can undergo a macroscopic quantum tunneling (MQT) process at temperatures below the crossover temperature. Without a vortex trapped, the metastable state is not a potential minimum in space, but a potential minimum at zero phase difference. (orig.)

  14. Multifunctional Aerogel Thermal Protection Systems for Hypersonic Vehicles, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The overall objective of the Phase II project is to develop lightweight reinforced aerogel materials for use as the core structural insulation material in...

  15. Active Metamaterial Based Ultrasonic Guided Wave Transducer System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — An active and tunable metamaterial phased array transducer for guided wave mode selection with high intensity per driving channel and with dramatically lower modal...

  16. Heliopause Electrostatic Rapid Transit System (HERTS) (Phase II)

    Data.gov (United States)

    National Aeronautics and Space Administration — Our proposal builds upon our teams technical findings in Phase 1 - that an E-Sail propelled spacecraft can travel 100 AU in less than 10 years or to the Heliopause...

  17. Novel Instrumentation for Rocket Propulsion Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of the proposed SBIR Phase I program is to develop novel laser-based instruments that provide rapid, in situ, simultaneous measurements of gas...

  18. Recession-Tolerant Sensors for Thermal Protection Systems, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The Phase II project will develop a suite of diagnostic sensors using Direct Write technology to measure temperature, surface recession depth, and heat flux of an...

  19. High Temperature Fiberoptic Thermal Imaging System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed Phase 1 program will fabricate and demonstrate a small diameter single fiber endoscope that can perform high temperature thermal imaging in a jet engine...

  20. Quantum and thermal phase escape in extended Josephson systems

    Energy Technology Data Exchange (ETDEWEB)

    Kemp, A.

    2006-07-12

    In this work I examine phase escape in long annular Josephson tunnel junctions. The sine-Gordon equation governs the dynamics of the phase variable along the junction. This equation supports topological soliton solutions, which correspond to quanta of magnetic flux trapped in the junction barrier. For such Josephson vortices an effective potential is formed by an external magnetic field, while a bias current acts as a driving force. Both together form a metastable potential well, which the vortex is trapped in. When the driving force exceeds the pinning force of the potential, the vortex escapes and the junction switches to the voltage state. At a finite temperature the driving force fluctuates. If the junction's energy scale is small, the phase variable can undergo a macroscopic quantum tunneling (MQT) process at temperatures below the crossover temperature. Without a vortex trapped, the metastable state is not a potential minimum in space, but a potential minimum at zero phase difference. (orig.)

  1. Fiber Optic Sensor System for Cryogenic Fuel Measurement, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR Phase I project will address the feasibility of using a fiber Bragg grating array as a means of detecting liquid and slush hydrogen in gravity and zero...

  2. Phase Transformations and Phase Equilibria in the Fe-N System at Temperatures below 573 K

    DEFF Research Database (Denmark)

    Malinov, S.; Böttger, A.J.; Mittemeijer, E.J.

    2001-01-01

    The phase transformations of homogeneous Fe-N alloys of nitrogen contents from 10 to 26 at. pct were investigated by means of X-ray diffraction analysis upon aging in the temperature range from 373 to 473 K. It was found that precipitation of alpha double prime-Fe16N2 below 443 K does not only oc...

  3. Modeling of diffusional phase transformation in multi-component systems with stoichiometric phases

    Czech Academy of Sciences Publication Activity Database

    Svoboda, Jiří; Fischer, F. D.; Abart, R.

    2010-01-01

    Roč. 58, č. 8 (2010), s. 2905-2911 ISSN 1359-6454 R&D Projects: GA MŠk(CZ) OC10029 Institutional research plan: CEZ:AV0Z20410507 Keywords : Interdiffusion * Intermetallics * Phase transformation kinetics Subject RIV: BJ - Thermodynamics Impact factor: 3.781, year: 2010

  4. Phase equilibria, crystal structure and oxygen content of intermediate phases in the Y-Ba-Co-O system

    OpenAIRE

    Urusova, A. S.; Cherepanov, V. A.; Aksenova, T. V.; Gavrilova, L. Y.; Kiselev, E. A.

    2013-01-01

    The phase equilibria in the Y-Ba-Co-O system were systematically studied at 1373 K in air. The intermediate phases formed in the Y-Ba-Co-O system at 1373 K in air were: YBaCo2O5+δ, YBaCo4O 7 and BaCo1-yYyO3-δ (0.09≤y≤0.42). It was shown that YBaCo2O5+δ possesses tetragonal structure with the 3ap×3a p×2ap superstructure (sp. gr. P4/mmm). High-temperature X-ray diffraction analysis of the YBaCo2O 5+δ in the temperature range from 298 K up to 1073 K under Po2=0.21 atm has not shown any phase tra...

  5. Predictive Modelling of Phase-Transfer Catalyst Systems for Improved and Innovative Design

    DEFF Research Database (Denmark)

    Anantpinijwatna, Amata; Hyung Kim, Sun; Sales-Cruz, Mauricio

    2016-01-01

    Phase-transfer catalyst (PTC) systems contain two immiscible liquid phases with a heterogeneous PTC transferring active ion from one phase to the other for converting the reactant to the desired product, and in the process generating the inactive ion. This type of reacting systems is receiving...... increasing attention as a novel organic synthesis option due to its flexible and easier operation, higher production yield, and ability to eliminate expensive solvents, although, not eliminating the use of solvents. New mathematical models of the PTC system, which includes physical and chemical equilibrium......, reaction mechanism and unit operation has been developed. In the developed model, the PTC system is divided into four sub-systems of aqueous-organic solvent partition, inorganic salt in aqueous phase, PTC in aqueous phase, and PTC in aqueous phase. Each subsystem requires an appropriate thermodynamic model...

  6. Recent Advances on Neuromorphic Systems Using Phase-Change Materials

    Science.gov (United States)

    Wang, Lei; Lu, Shu-Ren; Wen, Jing

    2017-05-01

    Realization of brain-like computer has always been human's ultimate dream. Today, the possibility of having this dream come true has been significantly boosted due to the advent of several emerging non-volatile memory devices. Within these innovative technologies, phase-change memory device has been commonly regarded as the most promising candidate to imitate the biological brain, owing to its excellent scalability, fast switching speed, and low energy consumption. In this context, a detailed review concerning the physical principles of the neuromorphic circuit using phase-change materials as well as a comprehensive introduction of the currently available phase-change neuromorphic prototypes becomes imperative for scientists to continuously progress the technology of artificial neural networks. In this paper, we first present the biological mechanism of human brain, followed by a brief discussion about physical properties of phase-change materials that recently receive a widespread application on non-volatile memory field. We then survey recent research on different types of neuromorphic circuits using phase-change materials in terms of their respective geometrical architecture and physical schemes to reproduce the biological events of human brain, in particular for spike-time-dependent plasticity. The relevant virtues and limitations of these devices are also evaluated. Finally, the future prospect of the neuromorphic circuit based on phase-change technologies is envisioned.

  7. Recent Advances on Neuromorphic Systems Using Phase-Change Materials.

    Science.gov (United States)

    Wang, Lei; Lu, Shu-Ren; Wen, Jing

    2017-12-01

    Realization of brain-like computer has always been human's ultimate dream. Today, the possibility of having this dream come true has been significantly boosted due to the advent of several emerging non-volatile memory devices. Within these innovative technologies, phase-change memory device has been commonly regarded as the most promising candidate to imitate the biological brain, owing to its excellent scalability, fast switching speed, and low energy consumption. In this context, a detailed review concerning the physical principles of the neuromorphic circuit using phase-change materials as well as a comprehensive introduction of the currently available phase-change neuromorphic prototypes becomes imperative for scientists to continuously progress the technology of artificial neural networks. In this paper, we first present the biological mechanism of human brain, followed by a brief discussion about physical properties of phase-change materials that recently receive a widespread application on non-volatile memory field. We then survey recent research on different types of neuromorphic circuits using phase-change materials in terms of their respective geometrical architecture and physical schemes to reproduce the biological events of human brain, in particular for spike-time-dependent plasticity. The relevant virtues and limitations of these devices are also evaluated. Finally, the future prospect of the neuromorphic circuit based on phase-change technologies is envisioned.

  8. Electrical system using phase-shifted carrier signals and related operating methods

    Science.gov (United States)

    Welchko, Brian A; Campbell, Jeremy B

    2012-09-18

    An automotive drive system and methods for making the same are provided. The system includes a three-phase motor and an inverter module. The three-phase motor includes a first set of windings each having a first magnetic polarity; and a second set of windings each having a second magnetic polarity that is opposite the first magnetic polarity. The first set of windings being electrically isolated from the second set of windings. The inverter module includes a first set of phase legs and a second set of phase legs. Each one of the first set of phase legs is coupled to a corresponding phase of the first set of windings, and each one of the second set of phase legs is coupled to a corresponding phase of the second set of windings.

  9. Prototype phase and amplitude feedback-control systems for the FMIT accelerator

    International Nuclear Information System (INIS)

    Fazio, M.V.; Patton, R.D.

    1983-01-01

    The phase and amplitude feedback-control systems for the Fusion Materials irradiation Test (FMIT) accelerator have been successfully prototyped and tested. The testing was performed at low power with two 100-W rf systems driving a high-Q resonant cavity at 80 MHz. The control systems can maintain the cavity field amplitude to within +-1% and the phase to within +-1 0 of the set-point values. When there are multiple rf systems independently driving a resonant cavity through individual drive loops, amplitude matching and proper phasing between the outputs of each rf system are essential for proper system operation. Experimental results are presented

  10. Phase-locked loops. [in analog and digital circuits communication system

    Science.gov (United States)

    Gupta, S. C.

    1975-01-01

    An attempt to systematically outline the work done in the area of phase-locked loops which are now used in modern communication system design is presented. The analog phase-locked loops are well documented in several books but discrete, analog-digital, and digital phase-locked loop work is scattered. Apart from discussing the various analysis, design, and application aspects of phase-locked loops, a number of references are given in the bibliography.

  11. Phase Equilibria of Sn-Co-Cu Ternary System

    Science.gov (United States)

    Chen, Yu-Kai; Hsu, Chia-Ming; Chen, Sinn-Wen; Chen, Chih-Ming; Huang, Yu-Chih

    2012-10-01

    Sn-Co-Cu ternary alloys are promising lead-free solders, and isothermal sections of Sn-Co-Cu phase equilibria are fundamentally important for the alloys' development and applications. Sn-Co-Cu ternary alloys were prepared and equilibrated at 523 K, 1073 K, and 1273 K (250 °C, 800 °C, and 1000 °C), and the equilibrium phases were experimentally determined. In addition to the terminal solid solutions and binary intermetallic compounds, a new ternary compound, Sn3Co2Cu8, was found. The solubilities of Cu in the α-CoSn3 and CoSn2 phases at 523 K (250 °C) are 4.2 and 1.6 at. pct, respectively, while the Cu solubility in the α-Co3Sn2 phase is as high as 20.0 at. pct. The Cu solubility increases with temperature and is around 30.0 at. pct in the β-Co3Sn2 at 1073 K (800 °C). The Co solubility in the η-Cu6Sn5 phase is also significant and is 15.5 at. pct at 523 K (250 °C).

  12. MIDAS, prototype Multivariate Interactive Digital Analysis System, Phase 1. Volume 2: Diagnostic system

    Science.gov (United States)

    Kriegler, F. J.; Christenson, D.; Gordon, M.; Kistler, R.; Lampert, S.; Marshall, R.; Mclaughlin, R.

    1974-01-01

    The MIDAS System is a third-generation, fast, multispectral recognition system able to keep pace with the large quantity and high rates of data acquisition from present and projected sensors. A principal objective of the MIDAS Program is to provide a system well interfaced with the human operator and thus to obtain large overall reductions in turn-around time and significant gains in throughout. The hardware and software generated in Phase I of the over-all program are described. The system contains a mini-computer to control the various high-speed processing elements in the data path and a classifier which implements an all-digital prototype multivariate-Gaussian maximum likelihood decision algorithm operating 2 x 105 pixels/sec. Sufficient hardware was developed to perform signature extraction from computer-compatible tapes, compute classifier coefficients, control the classifier operation, and diagnose operation. Diagnostic programs used to test MIDAS' operations are presented.

  13. Applications of the automatic ultrasonic testing system ALOK combined with a phased array system

    International Nuclear Information System (INIS)

    Stanger, H.K.; Kappes, W.; Licht, R.; Bohn, H.; Barbian, O.A.

    1987-01-01

    The combination of the automatic testing system ALOK with a controlled probe in the form of a phased array device is a possibility to meet the high requirements on the test method with regard to the statements of the test as well as the requirements on the reduction of operation and preparation times. The system's applications are not limited to the testing of reactors in nuclear technology (basic tests and recurring tests of the RPV and other primary circuit components); they are also of great importance in the non-nuclear sector e.g. the testing of pipelines, of reactors in the chemical field and of offshore structures as well as tests of components in the field of production. The modularity of the system permits an adaptation to the particular testing task with the possibility of using different manipulation and hardware systems. (orig./DG) [de

  14. Continuous fractional-order Zero Phase Error Tracking Control.

    Science.gov (United States)

    Liu, Lu; Tian, Siyuan; Xue, Dingyu; Zhang, Tao; Chen, YangQuan

    2018-04-01

    A continuous time fractional-order feedforward control algorithm for tracking desired time varying input signals is proposed in this paper. The presented controller cancels the phase shift caused by the zeros and poles of controlled closed-loop fractional-order system, so it is called Fractional-Order Zero Phase Tracking Controller (FZPETC). The controlled systems are divided into two categories i.e. with and without non-cancellable (non-minimum-phase) zeros which stand in unstable region or on stability boundary. Each kinds of systems has a targeted FZPETC design control strategy. The improved tracking performance has been evaluated successfully by applying the proposed controller to three different kinds of fractional-order controlled systems. Besides, a modified quasi-perfect tracking scheme is presented for those systems which may not have available future tracking trajectory information or have problem in high frequency disturbance rejection if the perfect tracking algorithm is applied. A simulation comparison and a hardware-in-the-loop thermal peltier platform are shown to validate the practicality of the proposed quasi-perfect control algorithm. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  15. PAPR Reduction in All-optical OFDM Systems Based on Phase Pre-emphasis

    Energy Technology Data Exchange (ETDEWEB)

    He Zhou; Li, Wei; Shao Jing; Liang Xiaojun; Huang Dexiu [Wuhan National Lab for Optoelectronics, Department of Optoelectronics Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Tao Zhiyong [State Key Laboratory of Optical Communication Technologies and Networks, Wuhan Research Institute of Posts and Telecommunications, Wuhan 430074 (China); Deng Zhuanhua, E-mail: hezhou@wri.com.cn, E-mail: weilee@mail.hust.edu.cn [School of Computer Science and Technology, Hubei University of Economics, Wuhan 430205 (China)

    2011-02-01

    This paper investigates the peak-to-average power ratio (PAPR) theory in all-optical orthogonal frequency division multiplexing (OFDM) optical fibre communication systems. We find out that phase pre-emphasis could effectively reduce PAPR in all-optical OFDM communication systems which employ intensity modulation-direct detection (IM-DD) method. An equation is developed and proposed to calculate suitable phasing values for pre-emphasis. Furthermore, we find out that phase pre-emphasis cannot reduce PAPR effectively in all-optical OFDM systems that employ Phase Shift Keying (PSK) or Quadracture Amplitude Modulation (QAM) method.

  16. PAPR Reduction in All-optical OFDM Systems Based on Phase Pre-emphasis

    International Nuclear Information System (INIS)

    He Zhou; Li, Wei; Shao Jing; Liang Xiaojun; Huang Dexiu; Tao Zhiyong; Deng Zhuanhua

    2011-01-01

    This paper investigates the peak-to-average power ratio (PAPR) theory in all-optical orthogonal frequency division multiplexing (OFDM) optical fibre communication systems. We find out that phase pre-emphasis could effectively reduce PAPR in all-optical OFDM communication systems which employ intensity modulation-direct detection (IM-DD) method. An equation is developed and proposed to calculate suitable phasing values for pre-emphasis. Furthermore, we find out that phase pre-emphasis cannot reduce PAPR effectively in all-optical OFDM systems that employ Phase Shift Keying (PSK) or Quadracture Amplitude Modulation (QAM) method.

  17. Phase diagram of the ternary Zr-Ti-Sn system

    International Nuclear Information System (INIS)

    Arias, D.; Gonzalez Camus, M.

    1987-01-01

    It is well known that Ti stabilizes the high temperature cubic phase of Zr and that Sn stabilizes the low temperature hexagonal phase of Zr. The effect of Sn on the Zr-Ti diagram has been studied in the present paper. Using high purity metals, nine different alloys have been prepared, with 4-32 at % Ti, 0.7-2.2 at % Sn and Zr till 100%. Resistivity and optical and SEM metallography techniques have been employed. Effect of some impurities have been analyzed. The results are discussed and different isothermic sections of the ternary Zr-Ti-Sn diagram are presented. (Author) [es

  18. Chaos crisis in coupled Duffing's systems with initial phase difference

    International Nuclear Information System (INIS)

    Bi Qinsheng

    2007-01-01

    The dynamics of coupled Duffing's oscillators with initial phase difference is investigated in this Letter. For the averaged equations, different equilibrium points can be observed, the number of which may vary with the parameters. The stable equilibrium points, corresponding to the periodic motion of the original coupled oscillators, may coexist with different patterns of dynamics, including chaos. Furthermore, two different chaotic attractors associated with different attracting basin coexist for certain parameter conditions, which may interact with each other to form an enlarged chaotic attractor. Several new dynamical phenomena such as boundary chaos crises have been predicted as the initial phase difference varies

  19. Non-destructive evaluation of welding part of stainless steels by phased array system

    International Nuclear Information System (INIS)

    Tatematsu, Nobuhiro; Matsumoto, Eiji

    2009-01-01

    Recently, more accurate and convenient Non-Destructive Evaluation techniques are required for flaw inspection of structural materials. Phased array ultrasonic transducers are expected as such as NDE technique but there are many subjects to be solved. Furthermore, commercial phased array systems with conventional scanning and imaging techniques have not fulfilled their maximum potential. The purpose of this paper is to improve the phased array system to be applicable to the inhomogeneity evaluation of welding part of stainless steels. (author)

  20. Deep learning the quantum phase transitions in random two-dimensional electron systems

    International Nuclear Information System (INIS)

    Ohtsuki, Tomoki; Ohtsuki, Tomi

    2016-01-01

    Random electron systems show rich phases such as Anderson insulator, diffusive metal, quantum Hall and quantum anomalous Hall insulators, Weyl semimetal, as well as strong/weak topological insulators. Eigenfunctions of each matter phase have specific features, but owing to the random nature of systems, determining the matter phase from eigenfunctions is difficult. Here, we propose the deep learning algorithm to capture the features of eigenfunctions. Localization-delocalization transition, as well as disordered Chern insulator-Anderson insulator transition, is discussed. (author)

  1. A new PLL system using full order observer and PLL system modeling in a single phase grid-connected inverter

    DEFF Research Database (Denmark)

    Ko, Youngjong; Park, Kiwoo; Lee, Kyo-Beum

    2011-01-01

    In a grid connected power conversion system, the phase angle information of a grid voltage is very essential for supplying power to the grid since it is used for active and reactive power control. A Phase Locked Loop (PLL) system is used and should be robust because often the actual grid voltages...

  2. Performance requirements for the double-shell tank system: Phase 1

    International Nuclear Information System (INIS)

    Claghorn, R.D.

    1998-01-01

    This document establishes performance requirements for the double-shell tank system. These requirements, in turn, will be incorporated in the System Specification for the Double-Shell Tank System (Grenard and Claghorn 1998). This version of the document establishes requirements that are applicable to the first phase (Phase 1) of the Tank Waste Remediation System (TWRS) mission described in the TWRS Mission Analysis Report (Acree 1998). It does not specify requirements for either the Phase 2 mission or the double-shell tank system closure period

  3. Preliminary study on radiation crosslinking of PE-NBR multiple phase system

    International Nuclear Information System (INIS)

    Wang Hong; Zhang Wanxi; Sun Jiazhen

    1989-01-01

    The effect of radiation crosslinking on the structure and properties of PE-NBR (polyethylene-acrylonitrile-butadiene rubber) multiple phase system was studied in this paper. The relationship of sol fraction and irradiated dose to multiplephase system was demonstrated

  4. Phase transitions in a system of hard Y-shaped particles on the triangular lattice

    Science.gov (United States)

    Mandal, Dipanjan; Nath, Trisha; Rajesh, R.

    2018-03-01

    We study the different phases and the phase transitions in a system of Y-shaped particles, examples of which include immunoglobulin-G and trinaphthylene molecules, on a triangular lattice interacting exclusively through excluded volume interactions. Each particle consists of a central site and three of its six nearest neighbors chosen alternately, such that there are two types of particles which are mirror images of each other. We study the equilibrium properties of the system using grand canonical Monte Carlo simulations that implement an algorithm with cluster moves that is able to equilibrate the system at densities close to full packing. We show that, with increasing density, the system undergoes two entropy-driven phase transitions with two broken-symmetry phases. At low densities, the system is in a disordered phase. As intermediate phases, there is a solidlike sublattice phase in which one type of particle is preferred over the other and the particles preferentially occupy one of four sublattices, thus breaking both particle symmetry as well as translational invariance. At even higher densities, the phase is a columnar phase, where the particle symmetry is restored, and the particles preferentially occupy even or odd rows along one of the three directions. This phase has translational order in only one direction, and breaks rotational invariance. From finite-size scaling, we demonstrate that both the transitions are first order in nature. We also show that the simpler system with only one type of particle undergoes a single discontinuous phase transition from a disordered phase to a solidlike sublattice phase with an increasing density of particles.

  5. Differentiation of surface properties of chlorococcalean algae by means of aqueous two phase systems

    Directory of Open Access Journals (Sweden)

    Jan Burczyk

    2014-01-01

    Full Text Available Algal cells belonging to various strains of Chlorococcales (Chlorophyta have been partitioned in aqueous two-phase systems containing ionogenic polymers, DEAE-dextran or SDS-dextran, at various pH values. Strain-specific differences of partition type which have been found in the phase systems used can be useful for distinguishing of algal cells.

  6. Phase diagram of the system Ca–Ti–O at 1200 K

    Indian Academy of Sciences (India)

    Phase relations in the system Ca–Ti–O have been established by equilibration of several samples at 1200 K for prolonged periods and identification of phases in quenched samples by optical and scanning electron microscopy, XRD and EDS. Samples representing 20 compositions in the ternary system were analyzed.

  7. On evolution of small spheres in the phase space of a dynamical system*

    Directory of Open Access Journals (Sweden)

    Komech Sergei

    2012-08-01

    Full Text Available We study the connection between the entropy of a dynamical system and the boundary distortion rate of regions in the phase space of the system. Nous étudions la connexion entre l’entropie d’un système dynamique et le taux de distortion au bord dans l’espace des phases du système.

  8. Development of a Fibre-Phased Array Laser-EMAT Ultrasonic System for Defect Inspection

    International Nuclear Information System (INIS)

    Pei, C; Demachi, K; Koyama, K; Uesaka, M; Fukuchi, T; Chen, Z

    2014-01-01

    In this work, a phased array laser ultrasound system with using fibre optic delivery and a custom-designed focusing objective lens has been developed for enhancing the ultrasound generation. The fibre-phased array method is applied to improve the sensitivity and detecting ability of the laser-EMAT system for defect inspection

  9. Phase equilibria of binary, ternary and quaternary systems for polymerization/depolymerization of polycarbonate

    NARCIS (Netherlands)

    Margon, V.; Agarwal, U.S.; Peters, C.J.; Wit, de G.; Bailly, C.M.E.; Kasteren, van J.M.N.; Lemstra, P.J.

    2005-01-01

    Vapor–liquid phase equilibrium is studied for the systems composed of phenol, diphenyl carbonate (DPC), bisphenol A (BPA) and CO2. Bubble point pressures and vapor-phase compositions are measured at various temperatures (343.15–473.15 K) for several compositions of the following systems: two binary

  10. X-ray phase analysis in leucite systems

    Czech Academy of Sciences Publication Activity Database

    Maixner, J.; Kloužková, A.; Mrázová, M.; Kohoutková, Martina

    2007-01-01

    Roč. 26, č. 2 (2007), s. 531-536 ISSN 0044-2968 R&D Projects: GA MPO 2A-1TP1/063 Institutional research plan: CEZ:AV0Z40320502 Keywords : cubic leucite * phase transformation * X-ray powder diffraction Subject RIV: CA - Inorganic Chemistry Impact factor: 1.338, year: 2007

  11. The method for simultaneous extraction and back extraction in liquid three-phase system and equipment for simultaneous extraction and back extraction in liquid three-phase system

    International Nuclear Information System (INIS)

    Palyska, W.; Chmielewski, A.G.

    1992-01-01

    The method for simultaneous extraction and back extraction in liquid three-phase system has been worked out. The equipment designed for that process has been also subject of the patent. The interesting component is extracted first to intermediate phase consists of magnetic solvent keeping two extracting phases separately. The intermediate magnetic liquid has been kept in its position using a stable magnet maintained on the surface of the extraction vessel. Then the component pass from intermediate phase to the third phase as a result of back extraction. Mixing in the extraction and back extraction zones is organized by means of rotating shaft going along the whole apparatus. The extraction and back extraction processes occur simultaneously as a result of continuous flow of solvent in their zones. The single extraction back extraction facilities can be joined in larger batteries. 3 figs

  12. Phase Diagrams of the Aqueous Two-Phase Systems of Poly(ethylene glycol/Sodium Polyacrylate/Salts

    Directory of Open Access Journals (Sweden)

    Adalberto Pessoa Junior

    2011-03-01

    Full Text Available Aqueous two-phase systems consisting of polyethylene glycol (PEG, sodium polyacrylate (NaPAA, and a salt have been studied. The effects of the polymer size, salt type (NaCl, Na2SO4, sodium adipate and sodium azelate and salt concentrations on the position of the binodal curve were investigated. The investigated PEG molecules had a molar mass of 2,000 to 8,000 g/mol, while that of NaPAA was 8,000 g/mol. Experimental phase diagrams, and tie lines and calculated phase diagrams, based on Flory-Huggins theory of polymer solutions are presented. Due to strong enthalpic and entropic balancing forces, the hydrophobicity of the added salt has a strong influence on the position of the binodal, which could be reproduced by model calculations.

  13. High accuracy interface characterization of three phase material systems in three dimensions

    DEFF Research Database (Denmark)

    Jørgensen, Peter Stanley; Hansen, Karin Vels; Larsen, Rasmus

    2010-01-01

    Quantification of interface properties such as two phase boundary area and triple phase boundary length is important in the characterization ofmanymaterial microstructures, in particular for solid oxide fuel cell electrodes. Three-dimensional images of these microstructures can be obtained...... by tomography schemes such as focused ion beam serial sectioning or micro-computed tomography. We present a high accuracy method of calculating two phase surface areas and triple phase length of triple phase systems from subvoxel accuracy segmentations of constituent phases. The method performs a three phase...... polygonization of the interface boundaries which results in a non-manifold mesh of connected faces. We show how the triple phase boundaries can be extracted as connected curve loops without branches. The accuracy of the method is analyzed by calculations on geometrical primitives...

  14. Versatile real-time interferometer phase-detection system using high-speed digital techniques

    International Nuclear Information System (INIS)

    Mendell, D.S.; Willett, G.W.

    1977-01-01

    This paper describes the basic design and philosophy of a versatile real-time interferometer phase-detection system to be used on the 2XIIB and TMX magnetic-fusion experiments at Lawrence Livermore Laboratory. This diagnostics system is a satellite to a host computer and uses high-speed emitter-coupled logic techniques to derive data on real-time phase relationships. The system's input signals can be derived from interferometer outputs over a wide range of reference frequencies. An LSI-11 microcomputer is the interface between the high-speed phase-detection logic, buffer memory, human interaction, and host computer. Phase data on a storage CRT is immediately displayed after each experimental fusion shot. An operator can interrogate this phase data more closely from an interactive control panel, and the host computer can be simultaneously examining the system's buffer memory or arming the system for the next shot

  15. Kilowatt isotope power system, Phase II Plan. Volume IV. Teledyne FSCD vs GDS

    Energy Technology Data Exchange (ETDEWEB)

    1978-03-15

    This Volume contains Teledyne's input to the Kilowatt Isotope Power System Phase II Plan. Included is a description of the Flight System Heat Generation System, Flight System Radiator, Thermal Insulation Stability, GDS Heat Generation System and GDS Radiator.

  16. Recent progresses and achievements in photovoltaic-phase change material technology: A review with special treatment on photovoltaic thermal-phase change material systems

    International Nuclear Information System (INIS)

    Islam, M.M.; Pandey, A.K.; Hasanuzzaman, M.; Rahim, N.A.

    2016-01-01

    Highlights: • Broad summary of phase change materials based cooling for photovoltaic modules. • Compendium on phase change materials that are mostly used in photovoltaic systems. • Extension of heat availability period by 75–100% with phase change material. • Heat storage potential improves by 33–50% more with phase change material. • Future trend and move in photovoltaic thermal research. - Abstract: This communication lays out an appraisal on the recent works of phase change materials based thermal management techniques for photovoltaic systems with special focus on the so called photovoltaic thermal-phase change material system. Attempt has also been made to draw wide-ranging classification of both photovoltaic and photovoltaic thermal systems and their conventional cooling or heat harvesting methods developed so far so that feasible phase change materials application area in these systems can be pointed out. In addition, a brief literature on phase change materials with particular focus on their solar application has also been presented. Overview of the researches and studies establish that using phase change materials for photovoltaic thermal control is technically viable if some issues like thermal conductivity or phase stability are properly addressed. The photovoltaic thermal-phase change material systems are found to offer 33% (maximum 50%) more heat storage potential than the conventional photovoltaic-thermal water system and that with 75–100% extended heat availability period and around 9% escalation in output. Reduction in temperature attained with photovoltaic thermal-phase change material system is better than that with regular photovoltaic-thermal water system, too. Studies also show the potential of another emerging technology of photovoltaic thermal-microencapsulated phase change material system that makes use of microencapsulated phase change materials in thermal regulation. Future focus areas on photovoltaic thermal-phase change

  17. Benchmarking of Grid Fault Modes in Single-Phase Grid-Connected Photovoltaic Systems

    DEFF Research Database (Denmark)

    Yang, Yongheng; Blaabjerg, Frede; Zou, Zhixiang

    2013-01-01

    Pushed by the booming installations of singlephase photovoltaic (PV) systems, the grid demands regarding the integration of PV systems are expected to be modified. Hence, the future PV systems should become more active with functionalities of Low Voltage Ride-Through (LVRT) and grid support...... phase systems under grid faults. The intent of this paper is to present a benchmarking of grid fault modes that might come in future single-phase PV systems. In order to map future challenges, the relevant synchronization and control strategies are discussed. Some faulty modes are studied experimentally...... and provided at the end of this paper. It is concluded that there are extensive control possibilities in single-phase PV systems under grid faults. The Second Order General Integral based PLL technique might be the most promising candidate for future single-phase PV systems because of its fast adaptive...

  18. Experimental determination and thermodynamic modeling of phase equilibrium and protein partitioning in aqueous two-phase systems containing biodegradable salts

    International Nuclear Information System (INIS)

    Perez, Brenda; Malpiedi, Luciana Pellegrini; Tubío, Gisela; Nerli, Bibiana; Alcântara Pessôa Filho, Pedro de

    2013-01-01

    Highlights: ► Binodal data of systems (water + polyethyleneglycol + sodium) succinate are reported. ► Pitzer model describes the phase equilibrium of systems formed by polyethyleneglycol and biodegradable salts satisfactorily. ► This simple thermodynamic framework was able to predict the partitioning behaviour of model proteins acceptably well. - Abstract: Phase diagrams of sustainable aqueous two-phase systems (ATPSs) formed by polyethyleneglycols (PEGs) of different average molar masses (4000, 6000, and 8000) and sodium succinate are reported in this work. Partition coefficients (Kps) of seven model proteins: bovine serum albumin, catalase, beta-lactoglobulin, alpha-amylase, lysozyme, pepsin, urease and trypsin were experimentally determined in these systems and in ATPSs formed by the former PEGs and other biodegradable sodium salts: citrate and tartrate. An extension of Pitzer model comprising long and short-range term contributions to the excess Gibbs free energy was used to describe the (liquid + liquid) equilibrium. Comparison between experimental and calculated tie line data showed mean deviations always lower than 3%, thus indicating a good correlation. The partition coefficients were modeled by using the same thermodynamic approach. Predicted and experimental partition coefficients correlated quite successfully. Mean deviations were found to be lower than the experimental uncertainty for most of the assayed proteins.

  19. Permanent split capacitor single phase electric motor system

    Science.gov (United States)

    Kirschbaum, H.S.

    1984-08-14

    A permanent split capacitor single phase electric motor achieves balanced operation at more than one operating point by adjusting the voltage supplied to the main and auxiliary windings and adjusting the capacitance in the auxiliary winding circuit. An intermediate voltage tap on an autotransformer supplies voltage to the main winding for low speed operation while a capacitive voltage divider is used to adjust the voltage supplied to the auxiliary winding for low speed operation. 4 figs.

  20. A phase contrast imaging system for TEXT-U

    International Nuclear Information System (INIS)

    Chatterjee, R.; Hallock, G.A.; Gartman, M.L.

    1994-01-01

    A diagnostic to study plasma density fluctuations, Phase Contrast Imaging (PCI) has been developed for the Texas Experimental Tokamak-Upgrade. The diagnostic has a sensitivity of about 10 -4 n e0 and is capable of detecting a wide range of wavenumbers (0.5 cm -1 - 12 cm -1 ) with a bandwidth of 500 Khz. The design of the diagnostic, some results of acoustic calibration tests and preliminary results of simulation of expected spectra are presented

  1. Breathing chimera in a system of phase oscillators

    Science.gov (United States)

    Bolotov, M. I.; Smirnov, L. A.; Osipov, G. V.; Pikovsky, A. S.

    2017-09-01

    Chimera states consisting of synchronous and asynchronous domains in a medium of nonlinearly coupled phase oscillators have been considered. Stationary inhomogeneous solutions of the Ott-Antonsen equation for a complex order parameter that correspond to fundamental chimeras have been constructed. The direct numerical simulation has shown that these structures under certain conditions are transformed to oscillatory (breathing) chimera regimes because of the development of instability.

  2. Experimentally determined chaotic phase synchronization in a neuronal system

    OpenAIRE

    Makarenko, Vladimir; Llinás, Rodolfo

    1998-01-01

    Mathematical analysis of the subthreshold oscillatory properties of inferior olivary neurons in vitro indicates that the oscillation is nonlinear and supports low dimensional chaotic dynamics. This property leads to the generation of complex functional states that can be attained rapidly via phase coherence that conform to the category of “generalized synchronization.” Functionally, this translates into neuronal ensemble properties that can support maximum functional permissiveness and that r...

  3. Phase inductance estimation for switched reluctance motor using adaptive neuro-fuzzy inference system

    International Nuclear Information System (INIS)

    Daldaban, Ferhat; Ustkoyuncu, Nurettin; Guney, Kerim

    2006-01-01

    A new method based on an adaptive neuro-fuzzy inference system (ANFIS) for estimating the phase inductance of switched reluctance motors (SRMs) is presented. The ANFIS has the advantages of expert knowledge of the fuzzy inference system and the learning capability of neural networks. A hybrid learning algorithm, which combines the least square method and the back propagation algorithm, is used to identify the parameters of the ANFIS. The rotor position and the phase current of the 6/4 pole SRM are used to predict the phase inductance. The phase inductance results predicted by the ANFIS are in excellent agreement with the results of the finite element method

  4. Magnesium Hall Thruster for Solar System Exploration, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation being developed in this program is a Mg Hall Effect Thruster system that would open the door for In-Situ Resource Utilization based solar system...

  5. Sensor Area Network for Integrated Systems Health Management, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The term Integrated Systems Health Management (ISHM) is used to describe a capability that focuses on determining the condition of every element in a complex System...

  6. Distributed Rocket Engine Testing Health Monitoring System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The on-ground and Distributed Rocket Engine Testing Health Monitoring System (DiRETHMS) provides a system architecture and software tools for performing diagnostics...

  7. Integrated Damage-Adaptive Control System (IDACS), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — SSCI, in collaboration with Boeing Phantom Works, proposes to develop and test an efficient Integrated Damage Adaptive Control System (IDACS). The proposed system is...

  8. Defining Handling Qualities of Unmanned Aerial Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Unmanned Air Systems (UAS) are here to stay and operators are demanding access to the National Airspace System (NAS) for a wide variety of missions. This includes a...

  9. Novel Color Depth Mapping Imaging Sensor System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Autonomous and semi-autonomous robotic systems require information about their surroundings in order to navigate properly. A video camera machine vision system can...

  10. Novel Color Depth Mapping Imaging Sensor System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Autonomous and semi-autonomous robotic systems require information about their surroundings in order to navigate properly. A video camera machine vision system can...

  11. Phase noise estimation and mitigation for DCT-based coherent optical OFDM systems.

    Science.gov (United States)

    Yang, Chuanchuan; Yang, Feng; Wang, Ziyu

    2009-09-14

    In this paper, as an attractive alternative to the conventional discrete Fourier transform (DFT) based orthogonal frequency division multiplexing (OFDM), discrete cosine transform (DCT) based OFDM which has certain advantages over its counterpart is studied for optical fiber communications. As is known, laser phase noise is a major impairment to the performance of coherent optical OFDM (CO-OFDM) systems. However, to our knowledge, detailed analysis of phase noise and the corresponding mitigation methods for DCT-based CO-OFDM systems have not been reported yet. To address these issues, we analyze the laser phase noise in the DCT-based CO-OFDM systems, and propose phase noise estimation and mitigation schemes. Numerical results show that the proposal is very effective in suppressing phase noise and could significantly improve the performance of DCT-based CO-OFDM systems.

  12. Development of portable phased array UT system for real-time flaw imaging

    International Nuclear Information System (INIS)

    Goto, M.

    1995-01-01

    Many functions and features of phased array UT technology must be useful for NDE in the industrial field. Some phased array UT systems have been developed for the inspection of nuclear pressure vessel and turbine components. However, phased array UT is still a special NDE technique and it has not been used widely in the past. The reasons of that are system size, cost, operator performance, equipment design and others. TOSHIBA has newly developed PC controlled portable phased array system to solve those problems. The portable phased array UT system is very compact and light but it is able to drive up to 32-channel linear array probe, to display real-time linear/sector B-scan, to display accumulated B-scan with an encoder and to display profile overlaid B-scan. The first applications were turbine component inspections for precise flaw investigation and flaw image data recording

  13. Medical information, communication, and archiving system (MICAS): Phase II integration and acceptance testing

    Science.gov (United States)

    Smith, Edward M.; Wandtke, John; Robinson, Arvin E.

    1999-07-01

    The Medical Information, Communication and Archive System (MICAS) is a multi-modality integrated image management system that is seamlessly integrated with the Radiology Information System (RIS). This project was initiated in the summer of 1995 with the first phase being installed during the first half of 1997 and the second phase installed during the summer of 1998. Phase II enhancements include a permanent archive, automated workflow including modality worklist, study caches, NT diagnostic workstations with all components adhering to Digital Imaging and Communications in Medicine (DICOM) standards. This multi-vendor phased approach to PACS implementation is designed as an enterprise-wide PACS to provide images and reports throughout our healthcare network. MICAS demonstrates that aa multi-vendor open system phased approach to PACS is feasible, cost-effective, and has significant advantages over a single vendor implementation.

  14. Overview of Single-Phase Grid-Connected Photovoltaic Systems

    DEFF Research Database (Denmark)

    Yang, Yongheng; Blaabjerg, Frede

    2015-01-01

    A still booming installation of solar photovoltaic (PV) systems has been witnessed worldwide. It is mainly driven by the demand of “clean” power generation. Grid-connected PV systems will become an even active player in the future mixed power systems, which are linked by a vast of power electronics...

  15. Thermal analysis of hybrid single-phase, two-phase and heat pump thermal control system (TCS) for future spacecraft

    International Nuclear Information System (INIS)

    Lee, S.H.; Mudawar, I.; Hasan, Mohammad M.

    2016-01-01

    Highlights: • Hybrid Thermal Control System (H-TCS) is proposed for future spacecraft. • Thermodynamic performance of H-TCS is examined for different space missions. • Operational modes including single-phase, two-phase and heat pump are explored. • R134a is deemed most appropriate working fluid. - Abstract: An urgent need presently exists to develop a new class of versatile spacecraft capable of conducting different types of missions and enduring varying gravitational and temperature environments, including Lunar, Martian and Near Earth Object (NEOs). This study concerns the spacecraft's Thermal Control System (TCS), which tackles heat acquisition, especially from crew and avionics, heat transport, and ultimate heat rejection by radiation. The primary goal of the study is to explore the design and thermal performance of a Hybrid Thermal Control System (H-TCS) that would satisfy the diverse thermal requirements of the different space missions. The H-TCS must endure both ‘cold’ and ‘hot’ environments, reduce weight and size, and enhance thermodynamic performance. Four different operational modes are considered: single-phase, two-phase, basic heat pump and heat pump with liquid-side, suction-side heat exchanger. A thermodynamic trade study is conducted for six different working fluids to assess important performance parameters including mass flow rate of the working fluid, maximum pressure, radiator area, compressor/pump work, and coefficient of performance (COP). R134a is determined to be most suitable based on its ability to provide a balanced compromise between reducing flow rate and maintaining low system pressure, and a moderate coefficient of performance (COP); this fluid is also both nontoxic and nonflammable, and features zero ozone depletion potential (ODP) and low global warming potential (GWP). It is shown how specific mission stages dictate which mode of operation is most suitable, and this information is used to size the radiator for the

  16. Overview of Single-Phase Grid-Connected Photovoltaic Systems

    OpenAIRE

    Yang, Yongheng; Blaabjerg, Frede

    2015-01-01

    A still booming installation of solar photovoltaic (PV) systems has been witnessed worldwide. It is mainly driven by the demand of “clean” power generation. Grid-connected PV systems will become an even active player in the future mixed power systems, which are linked by a vast of power electronics converters. In order to achieve a reliable and efficient power generation from PV systems, stringent demands have been imposed on the entire PV system. It in return advances the development of powe...

  17. Note: An improved calibration system with phase correction for electronic transformers with digital output.

    Science.gov (United States)

    Cheng, Han-miao; Li, Hong-bin

    2015-08-01

    The existing electronic transformer calibration systems employing data acquisition cards cannot satisfy some practical applications, because the calibration systems have phase measurement errors when they work in the mode of receiving external synchronization signals. This paper proposes an improved calibration system scheme with phase correction to improve the phase measurement accuracy. We employ NI PCI-4474 to design a calibration system, and the system has the potential to receive external synchronization signals and reach extremely high accuracy classes. Accuracy verification has been carried out in the China Electric Power Research Institute, and results demonstrate that the system surpasses the accuracy class 0.05. Furthermore, this system has been used to test the harmonics measurement accuracy of all-fiber optical current transformers. In the same process, we have used an existing calibration system, and a comparison of the test results is presented. The system after improvement is suitable for the intended applications.

  18. Note: An improved calibration system with phase correction for electronic transformers with digital output

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Han-miao, E-mail: chenghanmiao@hust.edu.cn; Li, Hong-bin, E-mail: lihongbin@hust.edu.cn [CEEE of Huazhong University of Science and Technology, Wuhan 430074 (China); State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Wuhan 430074 (China)

    2015-08-15

    The existing electronic transformer calibration systems employing data acquisition cards cannot satisfy some practical applications, because the calibration systems have phase measurement errors when they work in the mode of receiving external synchronization signals. This paper proposes an improved calibration system scheme with phase correction to improve the phase measurement accuracy. We employ NI PCI-4474 to design a calibration system, and the system has the potential to receive external synchronization signals and reach extremely high accuracy classes. Accuracy verification has been carried out in the China Electric Power Research Institute, and results demonstrate that the system surpasses the accuracy class 0.05. Furthermore, this system has been used to test the harmonics measurement accuracy of all-fiber optical current transformers. In the same process, we have used an existing calibration system, and a comparison of the test results is presented. The system after improvement is suitable for the intended applications.

  19. Phase-Image Encryption Based on 3D-Lorenz Chaotic System and Double Random Phase Encoding

    Science.gov (United States)

    Sharma, Neha; Saini, Indu; Yadav, AK; Singh, Phool

    2017-12-01

    In this paper, an encryption scheme for phase-images based on 3D-Lorenz chaotic system in Fourier domain under the 4f optical system is presented. The encryption scheme uses a random amplitude mask in the spatial domain and a random phase mask in the frequency domain. Its inputs are phase-images, which are relatively more secure as compared to the intensity images because of non-linearity. The proposed scheme further derives its strength from the use of 3D-Lorenz transform in the frequency domain. Although the experimental setup for optical realization of the proposed scheme has been provided, the results presented here are based on simulations on MATLAB. It has been validated for grayscale images, and is found to be sensitive to the encryption parameters of the Lorenz system. The attacks analysis shows that the key-space is large enough to resist brute-force attack, and the scheme is also resistant to the noise and occlusion attacks. Statistical analysis and the analysis based on correlation distribution of adjacent pixels have been performed to test the efficacy of the encryption scheme. The results have indicated that the proposed encryption scheme possesses a high level of security.

  20. Phase diagram of a symmetric electron-hole bilayer system: a variational Monte Carlo study.

    Science.gov (United States)

    Sharma, Rajesh O; Saini, L K; Bahuguna, Bhagwati Prasad

    2018-05-10

    We study the phase diagram of a symmetric electron-hole bilayer system at absolute zero temperature and in zero magnetic field within the quantum Monte Carlo approach. In particular, we conduct variational Monte Carlo simulations for various phases, i.e. the paramagnetic fluid phase, the ferromagnetic fluid phase, the anti-ferromagnetic Wigner crystal phase, the ferromagnetic Wigner crystal phase and the excitonic phase, to estimate the ground-state energy at different values of in-layer density and inter-layer spacing. Slater-Jastrow style trial wave functions, with single-particle orbitals appropriate for different phases, are used to construct the phase diagram in the (r s , d) plane by finding the relative stability of trial wave functions. At very small layer separations, we find that the fluid phases are stable, with the paramagnetic fluid phase being particularly stable at [Formula: see text] and the ferromagnetic fluid phase being particularly stable at [Formula: see text]. As the layer spacing increases, we first find that there is a phase transition from the ferromagnetic fluid phase to the ferromagnetic Wigner crystal phase when d reaches 0.4 a.u. at r s   =  20, and before there is a return to the ferromagnetic fluid phase when d approaches 1 a.u. However, for r s   Wigner crystal is stable over the considered range of r s and d. We also find that as r s increases, the critical layer separations for Wigner crystallization increase.

  1. Exotic Quantum Phases and Phase Transitions of Strongly Interacting Electrons in Low-Dimensional Systems

    Science.gov (United States)

    Mishmash, Ryan V.

    Experiments on strongly correlated quasi-two-dimensional electronic materials---for example, the high-temperature cuprate superconductors and the putative quantum spin liquids kappa-(BEDT-TTF)2Cu2(CN)3 and EtMe3Sb[Pd(dmit)2]2---routinely reveal highly mysterious quantum behavior which cannot be explained in terms of weakly interacting degrees of freedom. Theoretical progress thus requires the introduction of completely new concepts and machinery beyond the traditional framework of the band theory of solids and its interacting counterpart, Landau's Fermi liquid theory. In full two dimensions, controlled and reliable analytical approaches to such problems are severely lacking, as are numerical simulations of even the simplest of model Hamiltonians due to the infamous fermionic sign problem. Here, we attempt to circumvent some of these difficulties by studying analogous problems in quasi-one dimension. In this lower dimensional setting, theoretical and numerical tractability are on much stronger footing due to the methods of bosonization and the density matrix renormalization group, respectively. Using these techniques, we attack two problems: (1) the Mott transition between a Fermi liquid metal and a quantum spin liquid as potentially directly relevant to the organic compounds kappa-(BEDT-TTF)2Cu 2(CN)3 and EtMe3Sb[Pd(dmit)2] 2 and (2) non-Fermi liquid metals as strongly motivated by the strange metal phase observed in the cuprates. In both cases, we are able to realize highly exotic quantum phases as ground states of reasonable microscopic models. This lends strong credence to respective underlying slave-particle descriptions of the low-energy physics, which are inherently strongly interacting and also unconventional in comparison to weakly interacting alternatives. Finally, working in two dimensions directly, we propose a new slave-particle theory which explains in a universal way many of the intriguing experimental results of the triangular lattice organic spin

  2. Enhanced two phase flow in heat transfer systems

    Science.gov (United States)

    Tegrotenhuis, Ward E; Humble, Paul H; Lavender, Curt A; Caldwell, Dustin D

    2013-12-03

    A family of structures and designs for use in devices such as heat exchangers so as to allow for enhanced performance in heat exchangers smaller and lighter weight than other existing devices. These structures provide flow paths for liquid and vapor and are generally open. In some embodiments of the invention, these structures can also provide secondary heat transfer as well. In an evaporate heat exchanger, the inclusion of these structures and devices enhance the heat transfer coefficient of the evaporation phase change process with comparable or lower pressure drop.

  3. Multistate and phase change selection in constitutional multivalent systems.

    Science.gov (United States)

    Barboiu, Mihail

    2012-01-01

    Molecular architectures and materials can be constitutionally self-sorted in the presence of different biomolecular targets or external physical stimuli or chemical effectors, thus responding to an external selection pressure. The high selectivity and specificity of different bioreceptors or self-correlated internal interactions may be used to describe the complex constitutional behaviors through multistate component selection from a dynamic library. The self-selection may result in the dynamic amplification of self-optimized architectures during the phase change process. The sol-gel resolution of dynamic molecular/supramolecular libraries leads to higher self-organized constitutional hybrid materials, in which organic (supramolecular)/inorganic domains are reversibily connected.

  4. Efficient characterization of phase space mapping in axially symmetric optical systems

    Science.gov (United States)

    Barbero, Sergio; Portilla, Javier

    2018-01-01

    Phase space mapping, typically between an object and image plane, characterizes an optical system within a geometrical optics framework. We propose a novel conceptual frame to characterize the phase mapping in axially symmetric optical systems for arbitrary object locations, not restricted to a specific object plane. The idea is based on decomposing the phase mapping into a set of bivariate equations corresponding to different values of the radial coordinate on a specific object surface (most likely the entrance pupil). These equations are then approximated through bivariate Chebyshev interpolation at Chebyshev nodes, which guarantees uniform convergence. Additionally, we propose the use of a new concept (effective object phase space), defined as the set of points of the phase space at the first optical element (typically the entrance pupil) that are effectively mapped onto the image surface. The effective object phase space provides, by means of an inclusion test, a way to avoid tracing rays that do not reach the image surface.

  5. Two-phase aqueous micellar systems: an alternative method for protein purification

    Directory of Open Access Journals (Sweden)

    Rangel-Yagui C. O.

    2004-01-01

    Full Text Available Two-phase aqueous micellar systems can be exploited in separation science for the extraction/purification of desired biomolecules. This article reviews recent experimental and theoretical work by Blankschtein and co-workers on the use of two-phase aqueous micellar systems for the separation of hydrophilic proteins. The experimental partitioning behavior of the enzyme glucose-6-phosphate dehydrogenase (G6PD in two-phase aqueous micellar systems is also reviewed and new results are presented. Specifically, we discuss very recent work on the purification of G6PD using: i a two-phase aqueous micellar system composed of the nonionic surfactant n-decyl tetra(ethylene oxide (C10E4, and (ii a two-phase aqueous mixed micellar system composed of C10E4 and the cationic surfactant decyltrimethylammonium bromide (C10TAB. Our results indicate that the two-phase aqueous mixed (C10E4/C10TAB micellar system can improve significantly the partitioning behavior of G6PD relative to that observed in the two-phase aqueous C10E4 micellar system.

  6. Phased mission modelling of systems with maintenance-free operating periods using simulated Petri nets

    Energy Technology Data Exchange (ETDEWEB)

    Chew, S.P.; Dunnett, S.J. [Department of Aeronautical and Automotive Engineering, Loughborough University, Loughborough, Leics (United Kingdom); Andrews, J.D. [Department of Aeronautical and Automotive Engineering, Loughborough University, Loughborough, Leics (United Kingdom)], E-mail: j.d.andrews@lboro.ac.uk

    2008-07-15

    A common scenario in engineering is that of a system which operates throughout several sequential and distinct periods of time, during which the modes and consequences of failure differ from one another. This type of operation is known as a phased mission, and for the mission to be a success the system must successfully operate throughout all of the phases. Examples include a rocket launch and an aeroplane flight. Component or sub-system failures may occur at any time during the mission, yet not affect the system performance until the phase in which their condition is critical. This may mean that the transition from one phase to the next is a critical event that leads to phase and mission failure, with the root cause being a component failure in a previous phase. A series of phased missions with no maintenance may be considered as a maintenance-free operating period (MFOP). This paper describes the use of a Petri net (PN) to model the reliability of the MFOP and phased missions scenario. The model uses Monte-Carlo simulation to obtain its results, and due to the modelling power of PNs, can consider complexities such as component failure rate interdependencies and mission abandonment. The model operates three different types of PN which interact to provide the overall system reliability modelling. The model is demonstrated and validated by considering two simple examples that can be solved analytically.

  7. Experimental determination of the phase equilibria in the Co-Fe-Zr ternary system

    International Nuclear Information System (INIS)

    Wang, C.P.; Yu, Y.; Zhang, H.H.; Hu, H.F.; Liu, X.J.

    2011-01-01

    Research highlights: → We determined four isothermal sections of the Co-Fe-Zr system from 1000 o C to 1300 o C. → No ternary compound was found in the Co-Fe-Zr ternary system. → The solubility of Fe in the liquid phase at 1300 o C is extremely large. → The (Co, Fe) 2 Zr phase form the continuous solution from Co-Zr side to Fe-Zr side. → The solubility of Zr in the fcc (Co, Fe) phase is extremely small. - Abstract: The phase equilibria in the Co-Fe-Zr ternary system were investigated by means of optical microscopy (OM), electron probe microanalysis (EPMA), X-ray diffraction (XRD), and differential scanning calorimetry (DSC) on equilibrated ternary alloys. Four isothermal sections of the Co-Fe-Zr ternary system at 1300 o C, 1200 o C, 1100 o C and 1000 o C were experimentally established. The experimental results indicate that (1) no ternary compound was found in this system; (2) the solubility of Fe in the liquid phase of the Co-rich corner at 1300 o C is extremely large; (3) the liquid phase in the Zr-rich corner and the (Co,Fe) 2 Zr phase form the continuous solid solutions from the Co-Zr side to the Fe-Zr side; (4) the solubility of Zr in the fcc (Co, Fe) phase is extremely small.

  8. Phased mission modelling of systems with maintenance-free operating periods using simulated Petri nets

    International Nuclear Information System (INIS)

    Chew, S.P.; Dunnett, S.J.; Andrews, J.D.

    2008-01-01

    A common scenario in engineering is that of a system which operates throughout several sequential and distinct periods of time, during which the modes and consequences of failure differ from one another. This type of operation is known as a phased mission, and for the mission to be a success the system must successfully operate throughout all of the phases. Examples include a rocket launch and an aeroplane flight. Component or sub-system failures may occur at any time during the mission, yet not affect the system performance until the phase in which their condition is critical. This may mean that the transition from one phase to the next is a critical event that leads to phase and mission failure, with the root cause being a component failure in a previous phase. A series of phased missions with no maintenance may be considered as a maintenance-free operating period (MFOP). This paper describes the use of a Petri net (PN) to model the reliability of the MFOP and phased missions scenario. The model uses Monte-Carlo simulation to obtain its results, and due to the modelling power of PNs, can consider complexities such as component failure rate interdependencies and mission abandonment. The model operates three different types of PN which interact to provide the overall system reliability modelling. The model is demonstrated and validated by considering two simple examples that can be solved analytically

  9. The analysis phase in development of knowledge-based systems

    International Nuclear Information System (INIS)

    Brooking, A.G.

    1986-01-01

    Over the past twenty years computer scientists have realized that, in order to produce reliable software that is easily modifiable, a proven methodology is required. Unlike conventional systems there is little knowledge of the life cycle of these knowledge-based systems. However, if the life cycle of conventional systems, it is not unreasonable to assume that analysis will come first. With respect to the analysis task there is an enormous difference in types of analysis. Conventional systems analysis is predominately concerned with what happens within the system. Typically, procedures will be noted in the way they relate to each other, the way data moves and changes within the system. There is often an example, on paper or machine, that can be observed

  10. Phase synchronized quasiperiodicity in power electronic inverter systems

    DEFF Research Database (Denmark)

    Zhusubaliyev, Zhanybai T.; Mosekilde, Erik; Andriyanov, Alexey I.

    2014-01-01

    The development of switch-mode operated power electronic converter systems has provided a broad range of new effective approaches to the conversion of electric power. In this paper we describe the transitions from regular periodic operation to quasiperiodicity and high-periodic resonance behavior...... findings are verified through comparison with an experimental inverter system. The results shed light on the transitions to quasiperiodicity and to various forms of three-frequency dynamics in non-smooth systems....

  11. Computational Models for Nonlinear Aeroelastic Systems, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Clear Science Corp. and Duke University propose to develop and demonstrate new and efficient computational methods of modeling nonlinear aeroelastic systems. The...

  12. Reliable High Performance Processing System (RHPPS), Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's exploration, science, and space operations systems are critically dependent on the hardware technologies used in their implementation. Specifically, the...

  13. Software Defined Common Processing System (SDCPS), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Coherent Logix, Incorporated proposes the Software Defined Common Processing System (SDCPS) program to facilitate the development of a Software Defined Radio...

  14. Reliable High Performance Processing System (RHPPS), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's exploration, science, and space operations systems are critically dependent on the hardware technologies used in their implementation. Specifically, the...

  15. Nonhazardous Urine Pretreatment Method for Future Exploration Systems, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — A nonhazardous urine pretreatment system prototype is proposed that will stabilize urine against biological growth or chemical instabilities without using hazardous...

  16. Spacesuit Sensing Data Display and Management System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — ZIN Technologies, Inc will breadboard an integrated electronic system for space suit application to acquire images, biomedical sensor signals and suit health &...

  17. A Gimbal-Stabilized Compact Hyperspectral Imaging System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The Gimbal-stabilized Compact Hyperspectral Imaging System (GCHIS) fully integrates multi-sensor spectral imaging, stereovision, GPS and inertial measurement,...

  18. Intelligent Flamefinder Detection and Alert System (IFDAS), Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Current hydrogen flame detection systems exhibit shortcomings ranging from limited detection range, to localization inaccuracy, limited sensitivity, false alarms,...

  19. Adaptive Rotorcraft Condition and Usage Tracking System (ARCUTS), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — International Electronic Machines (IEM), a leader in the development of innovative sensor solutions for transportation systems, will develop the Adaptive Rotorcraft...

  20. Software Defined Common Processing System (SDCPS), Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Coherent Logix, Incorporated (CLX) proposes the development of a Software Defined Common Processing System (SDCPS) that leverages the inherent advantages of an...

  1. Synchronization Methods for Three Phase Distributed Power Generation Systems

    DEFF Research Database (Denmark)

    Timbus, Adrian Vasile; Teodorescu, Remus; Blaabjerg, Frede

    2005-01-01

    Nowadays, it is a general trend to increase the electricity production using Distributed Power Generation Systems (DPGS) based on renewable energy resources such as wind, sun or hydrogen. If these systems are not properly controlled, their connection to the utility network can generate problems...... on the grid side. Therefore, considerations about power generation, safe running and grid synchronization must be done before connecting these systems to the utility network. This paper is mainly dealing with the grid synchronization issues of distributed systems. An overview of the synchronization methods...

  2. Model Updating Nonlinear System Identification Toolbox, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — ZONA Technology (ZONA) proposes to develop an enhanced model updating nonlinear system identification (MUNSID) methodology that utilizes flight data with...

  3. Advanced Wastewater Photo-oxidation System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Pioneer Astronautics proposes an advanced photocatalytic oxidation reactor for enhancing the reliability and performance of Water Recovery Post Processing systems...

  4. Web Based Distributed Coastal Image Analysis System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This project develops Web based distributed image analysis system processing the Moderate Resolution Imaging Spectroradiometer (MODIS) data to provide decision...

  5. Evaluated phase diagrams of binary metal-tellurium systems of the D-block transition elements

    International Nuclear Information System (INIS)

    Chattopadhyay, G.; Bharadwaj, S.R.

    1989-01-01

    The binary phase diagrams of metal-tellurium systems for twenty seven d-block transition elements have been critically evaluated. Complete phase diagrams are presented for the elements, chromium, manganese, iron, cobalt, nickel, copper, molybdenum, palladium, silver, lanthanum, platinum and gold, whereas, for scandium, titanium, vanadium, yttrium, zirconium, niobium, technitium, ruthenium, rhodium, hafnium, tantalum, tungsten , rhenium, osmium and iridium, the phase diagrams are incomplete and tentative. (author). 20 refs., 27 tabs., 27 figs

  6. The Cu-Te-Sb phase system at temperatures between 300 and 1000 degree C

    DEFF Research Database (Denmark)

    Karup-Møller, Sven

    1997-01-01

    Phase relations were determined in the Cu-Te-Sb phase system at 300, 350, 400, 500, 600, 700, 800, 900 and 1000 degree C. At temperatures between 400 and 900 degree C a cubic primitive ternary phase A exists. It has the empirical formula Cu(10.32-0.97x)Te(x)Sb(4-x) (Z=2, a=7.682 Å). A small liquid...

  7. Blind phase retrieval for aberrated linear shift-invariant imaging systems

    International Nuclear Information System (INIS)

    Yu, Rotha P; Paganin, David M

    2010-01-01

    We develop a means to reconstruct an input complex coherent scalar wavefield, given a through focal series (TFS) of three intensity images output from a two-dimensional (2D) linear shift-invariant optical imaging system with unknown aberrations. This blind phase retrieval technique unites two methods, namely (i) TFS phase retrieval and (ii) iterative blind deconvolution. The efficacy of our blind phase retrieval procedure has been demonstrated using simulated data, for a variety of Poisson noise levels.

  8. UTILITY ADVANCED TURBINE SYSTEMS (ATS) TECHNOLOGY READINESS TESTING PHASE 3 RESTRUCTURED (3R)

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2000-03-17

    This scope document defines the work scope for accomplishing the design of the GE MS7001H and MS9001H (7H and 9H) combined-cycle power systems under the original ATS Phase 3 DOE Cooperative Agreement No. DE-FC21-95MC31176, and incorporates changes in scope required to convert Phase 3 to the ''restructured'' Phase 3R as defined in Amendment A012 to the Cooperative Agreement.

  9. Phase transitions and dynamic entropy in small two-dimensional systems: Experiment and numerical simulation

    Energy Technology Data Exchange (ETDEWEB)

    Koss, K. G.; Petrov, O. F.; Myasnikov, M. I., E-mail: miasnikovmi@mail.ru; Statsenko, K. B.; Vasiliev, M. M. [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation)

    2016-07-15

    The results of experimental and numerical analysis are presented for phase transitions in strongly nonequilibrium small systems of strongly interacting Brownian particles. The dynamic entropy method is applied to analysis of the state of these systems. Experiments are carried out with kinetic heating of the structures of micron-size particles in a laboratory rf discharge plasma. Three phase states of these small systems are observed: crystalline, liquid, and transient. The mechanism of phase transitions in cluster structures of strongly interacting particles is described.

  10. Data and analyses of phase relations in the Ce-Fe-Sb ternary system.

    Science.gov (United States)

    Zhu, Daiman; Xu, Chengliang; Li, Changrong; Guo, Cuiping; Zheng, Raowen; Du, Zhenmin; Li, Junqin

    2018-02-01

    These data and analyses support the research article "Experimental study on phase relations in the Ce-Fe-Sb ternary system" Zhu et al. (2017) [1]. The data and analyses presented here include the experimental results of XRD, SEM and EPMA for the determination of the whole liquidus projection and the isothermal section at 823 K in the Ce-Fe-Sb system. All the results enable the understanding of the constituent phases and the solidification processes of the as-cast alloys as well as the phase relations and the equilibrium regions at 823 K in the Ce-Fe-Sb ternary system over the entire composition.

  11. Phase-ambiguity resolution for QPSK modulation systems. Part 1: A review

    Science.gov (United States)

    Nguyen, Tien Manh

    1989-01-01

    Part 1 reviews the current phase-ambiguity resolution techniques for QPSK coherent modulation systems. Here, those known and published methods of resolving phase ambiguity for QPSK with and without Forward-Error-Correcting (FEC) are discussed. The necessary background is provided for a complete understanding of the second part where a new technique will be discussed. An appropriate technique to the Consultative Committee for Space Data Systems (CCSDS) is recommended for consideration in future standards on phase-ambiguity resolution for QPSK coherent modulation systems.

  12. Application of New Electrolyte Model to Phase Transfer Catalyst (PTC) Systems

    DEFF Research Database (Denmark)

    Hyung Kim, Sun; Anantpinijwatna, Amata; Kang, Jeong Won

    2015-01-01

    Abstract Phase transfer catalyst (PTC) is used to transfer the desirable active form of an anion from the aqueous phase to organic phase where the reaction occurs. One of major challenges for process design of the PTC system is to establish a reliable thermodynamic model capable of describing pha...... in PTC systems, thereby, extending the application range of the PTC-system model. The solubility of PTC in organic solvents, which is a key factor for strategy of PTC and solvent selection, has been calculated using the e-NRTL-SAC model....

  13. Unconventional phases in quantum spin and pseudospin systems in two dimensional and three dimensional lattices

    Science.gov (United States)

    Xu, Cenke

    Several examples of quantum spin systems and pseudo spin systems have been studied, and unconventional states of matters and phase transitions have been realized in all these systems under consideration. In the p +/- ip superconductor Josephson lattice and the p--band cold atomic system trapped in optical lattices, novel phases which behave similarly to 1+1 dimensional systems are realized, despite the fact that the real physical systems are in two or three dimensional spaces. For instance, by employing a spin-wave analysis together with a new duality transformation, we establish the existence and stability of a novel gapless "critical phase", which we refer to as a "bond algebraic liquid". This novel critical phase is analogous to the 1+1 dimensional algebraic boson liquid phase. The reason for the novel physics is that there is a quasilocal gauge symmetry in the effective low energy Hamiltonian. In a spin-1 system on the kagome lattice, and a hard-core boson system on the honeycomb lattice, the low energy physics is controlled by two components of compact U(1) gauge symmetries that emerge at low energy. Making use of the confinement nature of the 2+1 dimensional compact gauge theories and the powerful duality between gauge theories and height field theories, the crystalline phase diagrams are studied for both systems, and the transitions to other phases are also considered. These phase diagrams might be accessible in strongly correlated materials, or atomic systems in optical lattices. A novel quantum ground state of matter is realized in a bosonic model on three dimensional fcc lattice with emergent low energy excitations. The novel phase obtained is a stable gapless boson liquid phase, with algebraic boson density correlations. The stability of this phase is protected against the instanton effect and superfluidity by self-duality and large gauge symmetries on both sides of the duality. The gapless collective excitations of this phase closely resemble the

  14. Geometric phases and quantum correlations of superconducting two-qubit system with dissipative effect

    International Nuclear Information System (INIS)

    Xue, Liyuan; Yu, Yanxia; Cai, Xiaoya; Pan, Hui; Wang, Zisheng

    2016-01-01

    Highlights: • We find that the Pancharatnam phases include the information of quantum correlations. • We show that the sudden died and alive phenomena of quantum entanglement is original in the transition of Pancharatnam phase. • We find that the faster the Pancharatnam phases change, the slower the quantum correlations decay. • We find that a subspace of quantum entanglement can exist in the Y-state. • Our results provide a useful approach experimentally to implement the time-dependent geometric quantum computation. - Abstract: We investigate time-dependent Pancharatnam phases and the relations between such geometric phases and quantum correlations, i.e., quantum discord and concurrence, of superconducting two-qubit coupling system in dissipative environment with the mixture effects of four different eigenstates of density matrix. We find that the time-dependent Pancharatnam phases not only keep the motion memory of such a two-qubit system, but also include the information of quantum correlations. We show that the sudden died and alive phenomena of quantum entanglement are intrinsic in the transition of Pancharatnam phase in the X-state and the complex oscillations of Pancharatnam phase in the Y-state. The faster the Pancharatnam phases change, the slower the quantum correlations decay. In particular, we find that a subspace of quantum entanglement can exist in the Y-state by choosing suitable coupling parameters between two-qubit system and its environment, or initial conditions.

  15. Model validation studies of solar systems, Phase III. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Lantz, L.J.; Winn, C.B.

    1978-12-01

    Results obtained from a validation study of the TRNSYS, SIMSHAC, and SOLCOST solar system simulation and design are presented. Also included are comparisons between the FCHART and SOLCOST solar system design programs and some changes that were made to the SOLCOST program. Finally, results obtained from the analysis of several solar radiation models are presented. Separate abstracts were prepared for ten papers.

  16. Thermodynamic calculation of phase equilibria of the U-Ga and U-W systems

    International Nuclear Information System (INIS)

    Wang, J.; Liu, X.J.; Wang, C.P.

    2008-01-01

    The thermodynamic assessments of the U-Ga and U-W systems have been carried out by using the CALPHAD (calculation of phase diagrams) method using experimental data including thermodynamic properties and phase equilibria. Gibbs free energies of the solution phases were described by the subregular solution models with the Redlich-Kister equation, and those of the intermetallic compounds were described by the sublattice models. A consistent set of thermodynamic parameters has been derived for the Gibbs free energy of each phase in the U-Ga and U-W binary systems, respectively. The calculated phase diagrams and thermodynamic properties in the U-Ga and U-W systems are in good agreement with experimental data

  17. Operation of a forced two phase cooling system on a large superconducting magnet

    International Nuclear Information System (INIS)

    Green, M.A.; Burns, W.A.; Eberhard, P.H.; Gibson, G.H.; Pripstein, M.; Ross, R.R.; Smits, R.G.; Taylor, J.D.; Van Slyke, H.

    1980-05-01

    This paper describes the operation of a forced two phase cooling system on a two meter diameter superconducting solenoid. The magnet is a thin high current density superconducting solenoid which is cooled by forced two phase helium in tubes around the coil. The magnet, which is 2.18 meters in diameter and 3.4 meters long, has a cold mass of 1700 kg. The two phase cooling system contains less than 300 liters of liquid helium, most of which is contained in a control dewar. This paper describes the operating characteristics of the LBL two phase forced cooling system during cooldown and warm up. The paper presents experimental data on operations of the magnet using either a helium pump or the refrigerator compressor to circulate two phase helium through the superconducting coil cooling tubes

  18. Phase relations and physicochemical properties of the ammonium paratungstate - polyvinyl alcohol - water system

    International Nuclear Information System (INIS)

    Ostroushko, A.A.; Mikhalev, D.S.

    2003-01-01

    Phase relations were studied in the ammonium paratungstate - polyvinyl alcohol - water system, isothermal cross section of the phase diagram was obtained at room temperature. Visual and microscopic observations, as well as instrumental methods were used for the detection of lines of the homogeneous polymer-salt solutions existence. Concentration ratios of density of solutions, their dynamic viscosity and refractive index were studied. Area of polymer based solutions, area of salt crystallization, heterogeneous fields with two or three phases were separated. As compared with the ammonium heptamolybdate - polyvinyl alcohol - water system the increase of solubility of components under day lighting and ultraviolet radiation escaped detection. The studied system is provided properties indicative of the formation of mesomorphic phase, photochemical reduction of ions of d-metals for the occurrence of this phase is not requirement [ru

  19. Prediction of phase equilibria in the In–Sb–Pb system

    Directory of Open Access Journals (Sweden)

    DUSKO MINIC

    2008-03-01

    Full Text Available Binary thermodynamic data, successfully used for phase diagram calculations of the binary systems In–Sb, Pb–Sb and In–Pb, were used for the prediction of the phase equilibria in the ternary In–Sb–Pb system. The predicted equilibrium phase diagram of the vertical Pb–InSb section was compared with the results of differential thermal analysis DTA and optical microscopy. The calculated phase diagram of the isothermal section at 300 °C was compared with the experimentally (SEM, EDX determined composition of phases in the chosen alloys after annealing. Very good agreement between the binary-based thermodynamic prediction and the experimental data was found in all cases. The calculated liquidus projection of the ternary In–Sb–Pb system is also presented.

  20. Different phases of a system of hard rods on three dimensional cubic lattice

    Science.gov (United States)

    Vigneshwar, N.; Dhar, Deepak; Rajesh, R.

    2017-11-01

    We study the different phases of a system of monodispersed hard rods of length k on a cubic lattice, using an efficient cluster algorithm able to simulate densities close to the fully-packed limit. For k≤slant 4 , the system is disordered at all densities. For k=5, 6 , we find a single density-driven transition, from a disordered phase to high density layered-disordered phase, in which the density of rods of one orientation is strongly suppressed, breaking the system into weakly coupled layers. Within a layer, the system is disordered. For k ≥slant 7 , three density-driven transitions are observed numerically: isotropic to nematic to layered-nematic to layered-disordered. In the layered-nematic phase, the system breaks up into layers, with nematic order in each layer, but very weak correlation between the ordering directions of different layers. We argue that the layered-nematic phase is a finite-size effect, and in the thermodynamic limit, the nematic phase will have higher entropy per site. We expect the systems of rods in four and higher dimensions will have a qualitatively similar phase diagram.

  1. The Cu-Sb-Se phase system at temperatures between 350 and 700 degree C

    DEFF Research Database (Denmark)

    Karup-Møller, Sven

    1999-01-01

    Phase relations were determined in the Cu-Sb-Se phase system at 300o, 400o, 450o, 500o, 600o and 700oC. Five three-component phases are present at 300oC: permingeatite (Cu3SbSe4), phase A (Cu3SbSe3, the Se-equivalent to skinnerite Cu3SbS3), phase B (CuSbSe2, the Se-equivalent to chalcostibite Cu......SbS2), phase C (Cu5.04Sb35.9Se59.1) and phase D (Cu38.8Sb6.10Se55.1). An X-ray crystallographic study is currently in progress on phase C. Phase D is present in insufficient amounts for such a study. At 400oC phase C and D does not exist and at 500oC all solid ternary phase are absent. At 450oC two...

  2. Model system studies with a phase separated membrane bioreactor

    Science.gov (United States)

    Petersen, G. R.; Seshan, P. K.; Dunlop, Eric H.

    1989-01-01

    The operation and evaluation of a bioreactor designed for high intensity oxygen transfer in a microgravity environment is described. The reactor itself consists of a zero headspace liquid phase separated from the air supply by a long length of silicone rubber tubing through which the oxygen diffuses in and the carbon dioxide diffuses out. Mass transfer studies show that the oxygen is film diffusion controlled both externally and internally to the tubing and not by diffusion across the tube walls. Methods of upgrading the design to eliminate these resistances are proposed. Cell growth was obtained in the fermenter using Saccharomyces cerevisiae showing that this concept is capable of sustaining cell growth in the terrestial simulation.

  3. Phase separated membrane bioreactor - Results from model system studies

    Science.gov (United States)

    Petersen, G. R.; Seshan, P. K.; Dunlop, E. H.

    1989-01-01

    The operation and evaluation of a bioreactor designed for high intensity oxygen transfer in a microgravity environment is described. The reactor itself consists of a zero headspace liquid phase separated from the air supply by a long length of silicone rubber tubing through which the oxygen diffuses in and the carbon dioxide diffuses out. Mass transfer studies show that the oxygen is film diffusion controlled both externally and internally to the tubing and not by diffusion across the tube walls. Methods of upgrading the design to eliminate these resistances are proposed. Cell growth was obtained in the fermenter using Saccharomyces cerevisiae showing that this concept is capable of sustaining cell growth in the terrestrial simulation.

  4. Phase separated membrane bioreactor: Results from model system studies

    Science.gov (United States)

    Petersen, G. R.; Seshan, P. K.; Dunlop, E. H.

    The operation and evaluation of a bioreactor designed for high intensity oxygen transfer in a microgravity environment is described. The reactor itself consists of a zero headspace liquid phase separated from the air supply by a long length of silicone rubber tubing through which the oxygen diffuses in and the carbon dioxide diffuses out. Mass transfer studies show that the oxygen is film diffusion controlled both externally and internally to the tubing and not by diffusion across the tube walls. Methods of upgrading the design to eliminate these resistances are proposed. Cell growth was obtained in the fermenter using Saccharomyces cerevisiae showing that this concept is capable of sustaining cell growth in the terrestial simulation.

  5. Spin interferometry and phase relations in three level systems

    International Nuclear Information System (INIS)

    Mehring, M.; Stoll, M.E.; Wolff, E.K.

    1978-01-01

    The sign of the wavefunctions of deuterium, a spin-1 nucleus, under a 2π rotation (spinor character) has been studied with using a single crystal of 98% deuterated hexamethyl-benzene (HMB, C 6 (CD 3 ) 6 ). In a large magnetic fields, the three energy levels of the Zeeman hamiltonian have equal spacing, whereas unequivalent transition frequencies may occur if a suitable quadrupolar interaction is included. Three types of experiment are discussed. Simultaneous irradiation of both transitions with a field strength ω 1 in the x direction verified spin-locking, quadrature, or phase variation; consecutive irradiation at both transition with π-pulses showed coherence transfer from transition 1-2 to the forbidden transition 1-3; double quantum spinor behavior was demonstrated by applying rf field of strength ω 1 = γH 1 at the 'double quantum transition' frequency ω 0

  6. A steerable/distance enhanced penetrometer delivery system: Phase II. Topical report

    International Nuclear Information System (INIS)

    Amini, A.; Shenhar, J.; Lum, K.D.

    1996-05-01

    This report summarizes the phase II work on the Position Location Device (POLO) for penetrometers. Phase II was carried out to generate an integrated design of a full-scale steerable/distance enhanced penetrometer delivery system. Steering provides for the controlled and directional use of the penetrometer, while vibratory thrusting can provide greater penetration ability

  7. Effects of mobile vacancies on the dynamics of ordering and phase separation in nonconserved multicomponent systems

    DEFF Research Database (Denmark)

    Gilhøj, Henriette; Jeppesen, Claus; Mouritsen, Ole G.

    1995-01-01

    The effects of mobile vacancies on the dynamics of ordering processes and phase separation in multicomponent systems are studied via Monte Carlo simulations of a two-dimensional seven-state ferromagnetic Potts model with varying degrees of site dilution. The model displays phase equilibria...

  8. Extraction of peptide tagged cutinase in detergent-based aqueous two-phase systems

    NARCIS (Netherlands)

    Rodenbrock, A.; Selber, K.; Egmond, M.R.; Kula, M.-R.

    2010-01-01

    Detergent-based aqueous two-phase systems have the advantage to require only one auxiliary chemical to induce phase separation above the cloud point. In a systematic study the efficiency of tryptophan-rich peptide tags was investigated to enhance the partitioning of an enzyme to the detergent-rich

  9. Phase control of light amplification with dynamically irreversible pathways of population transfer in a Λ system

    International Nuclear Information System (INIS)

    Yuan Shi; Wu Jinhui; Gao Jinyue; Pan Chunliu

    2002-01-01

    We use the relative phase of two coherent fields for the control of light amplification with dynamically irreversible pathways of population transfer in a Λ system. The population inversion and gain with dynamically irreversible pathways of population transfer are shown as the relative phase is varied. We support our results by numerical calculation and analytical explanation

  10. Energy management based on AM/FM/GIS for phase balancing application on distribution systems

    International Nuclear Information System (INIS)

    Kuo, C.-C.; Chao, Y.-T.

    2010-01-01

    Unbalanced feeder systems may deteriorate of power quality, and increase investment and operating costs for distribution systems. The phase swapping method recommends re-phasing circuits of laterals and transformers for making the current and voltage balanced and also reducing feeder loss and voltage drop. In this paper, an application program, based on the automated mapping/facilities management/ geographic information system (AM/FM/GIS) is developed which contains a function of automatically computing Z-bus, load flow and phase balancing of feeders with phase swapping by using easily selecting of feeder on a graphic user interface application. Therefore, the relative data need not be keyed in manually. The presented phase balancing algorithm are based on database and related data structures developed on the AM/FM/GIS and Visual Basic software, which can be integrated into the Tai-Power distribution automation system. Then, the phase balancing algorithm is designed to handle the load patterns and the load of transformers that connect specific feeders when evaluating phase swaps that will result in reduced daily circuit losses over all load points. The proposed application not only can effectively reduce the circuit loss and improves phase balancing, but also enhances power quality efficiently under easily using environment.

  11. Symmetrical components and power analysis for a two-phase microgrid system

    DEFF Research Database (Denmark)

    Alibeik, M.; Santos Jr., E. C. dos; Blaabjerg, Frede

    2014-01-01

    This paper presents a mathematical model for the symmetrical components and power analysis of a new microgrid system consisting of three wires and two voltages in quadrature, which is designated as a two-phase microgrid. The two-phase microgrid presents the following advantages: 1) constant power...

  12. Cooperative Telerobotic Retrieval system Phase 1 technology evaluation report

    Energy Technology Data Exchange (ETDEWEB)

    Hyde, R.A.; Croft, K.M.

    1995-03-01

    This document describes the results from the Cooperative Telerobotic Retrieval demonstration and testing conducted at the Idaho National Engineering Laboratory during December 1994 and January 1995. The purpose of the demonstration was to ascertain the feasibility of the system for deploying tools both independently and cooperatively for supporting remote characterization and removal of buried waste in a safe manner and in compliance with all regulatory requirements. The procedures and goals of the demonstration were previously defined in the Cooperative Telerobotic Retrieval System Test Plan for Fiscal Year 1994, which served as a guideline for evaluating the system.

  13. Coded diffraction system in X-ray crystallography using a boolean phase coded aperture approximation

    Science.gov (United States)

    Pinilla, Samuel; Poveda, Juan; Arguello, Henry

    2018-03-01

    Phase retrieval is a problem present in many applications such as optics, astronomical imaging, computational biology and X-ray crystallography. Recent work has shown that the phase can be better recovered when the acquisition architecture includes a coded aperture, which modulates the signal before diffraction, such that the underlying signal is recovered from coded diffraction patterns. Moreover, this type of modulation effect, before the diffraction operation, can be obtained using a phase coded aperture, just after the sample under study. However, a practical implementation of a phase coded aperture in an X-ray application is not feasible, because it is computationally modeled as a matrix with complex entries which requires changing the phase of the diffracted beams. In fact, changing the phase implies finding a material that allows to deviate the direction of an X-ray beam, which can considerably increase the implementation costs. Hence, this paper describes a low cost coded X-ray diffraction system based on block-unblock coded apertures that enables phase reconstruction. The proposed system approximates the phase coded aperture with a block-unblock coded aperture by using the detour-phase method. Moreover, the SAXS/WAXS X-ray crystallography software was used to simulate the diffraction patterns of a real crystal structure called Rhombic Dodecahedron. Additionally, several simulations were carried out to analyze the performance of block-unblock approximations in recovering the phase, using the simulated diffraction patterns. Furthermore, the quality of the reconstructions was measured in terms of the Peak Signal to Noise Ratio (PSNR). Results show that the performance of the block-unblock phase coded apertures approximation decreases at most 12.5% compared with the phase coded apertures. Moreover, the quality of the reconstructions using the boolean approximations is up to 2.5 dB of PSNR less with respect to the phase coded aperture reconstructions.

  14. Flexible and Safe Control of Mobile Surface Systems, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The primary innovation of this work is a novel approach for flexible and safe control of highly capable mobile surface systems, such as long-duration science rovers,...

  15. Extreme Temperature Motor and Drill System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — In response to the need for motors, actuators and drilling systems that can operate in the harsh venusian environment for extended periods of time, on the order of...

  16. Integration Framework for Building Autonomous Intelligent Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Among the many challenges of Mars exploration is the creation of autonomous systems that support crew activities without reliance on Earth mission control. These...

  17. Silver Ion Biocide Delivery System for Water Disinfection, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — U.S. space exploration missions have long considered returning to the Moon and exploration of Mars that challenge life support systems. For these long duration...

  18. Reactive In-flight Multisensor Security System (RIMSS), Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The need for in-flight event detection and monitoring systems is clear. To address this and other safety and security needs, IEM proposed the Reactive In-flight...

  19. Automated Flight Safety Inference Engine (AFSIE) System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop an innovative Autonomous Flight Safety Inference Engine (AFSIE) system to autonomously and reliably terminate the flight of an errant launch...

  20. Automated Mulitple Object Optical Tracking and Recognition System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — OPTRA proposes to develop an optical tracking system that is capable of recognizing and tracking up to 50 different objects within an approximately 2 degree x 3...

  1. Windhover Unmanned Aircraft Systems (UAS) Software Ecosystem, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The safety of Unmanned Aircraft Systems (UAS) flights is currently the responsibility of the pilot who is required to keep the vehicle within their line of sight...

  2. Architecture for Integrated System Health Management, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Managing the health of vehicle, crew, and habitat systems is a primary function of flight controllers today. We propose to develop an architecture for automating...

  3. A Verification and Validation Tool for Diagnostic Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Advanced diagnostic systems have the potential to improve safety, increase availability, and reduce maintenance costs in aerospace vehicle and a variety of other...

  4. Model Updating Nonlinear System Identification Toolbox, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — ZONA Technology proposes to develop an enhanced model updating nonlinear system identification (MUNSID) methodology by adopting the flight data with state-of-the-art...

  5. Sample Management System for Heavy Ion Irradiation, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — A robotic sample management device and system for the exposure of biological and material specimens to heavy ion beams of the NASA Space Radiation Laboratory (NSRL)...

  6. Sample Management System for Heavy Ion Irradiation, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — A robotic sample management device and system for the exposure of biological and material specimens to heavy ion beams of the NASA Space Radiation Laboratory (NSRL)...

  7. Distributed Force and Moment Measurement System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The structural design of aircraft and their propulsion systems is a challenging task that requires accurate, flexible ground facilities capable of operating over the...

  8. Core Flight Software for Unmanned Aircraft Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Use of Unmanned Aircraft Systems (UAS) is increasing worldwide, but multiple technical barriers restrict the greater use of UASs. The safe operation of UASs in the...

  9. Extreme Environment High Temperature Communication Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The purpose of this project is to develop and demonstrate a communications system capable of operation at extreme temperatures and pressures in hostile and corrosive...

  10. Defining Handling Qualities of Unmanned Aerial Systems, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Unmanned Air Systems (UAS) are no longer coming, they are here, and operators from first responders to commercial operators are demanding access to the National...

  11. Validation Tools and Methods for Diagnostic Systems, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The potential benefits of advanced algorithms for diagnostics and prognostics, inner-loop control, and other flight critical systems have been demonstrated in a...

  12. High Temperature Radiators for Electric Propulsion Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The VASIMR propulsion system uses a high temperature Loop Heat Pipe (LHP) radiator to reject heat from the helicon section. The current baseline radiator uses...

  13. Novel Composite Membrane for Space Life Supporting System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Space life-supporting systems require effective removal of metabolic CO2 from the cabin atmosphere with minimal loss of O2. Conventional techniques, using either...

  14. Carbonaceous Asteroid Volatile Recovery (CAVoR) system, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The Carbonaceous Asteroid Volatile Recovery (CAVoR) system produces water and hydrogen-rich syngas for propellant production, life support consumables, and...

  15. Aircraft Nodal Data Acquisition System (ANDAS), Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Development of an Aircraft Nodal Data Acquisition System (ANDAS) based upon the short haul Zigbee networking standard is proposed. It employs a very thin (135 um)...

  16. Miniature Intelligent Wireless Fire Detector System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this project is to develop a wireless intelligent dual-band photodetector system for advanced fire detection/recognition, combining UV/IR III...

  17. Heterogeneous Silicon Photonics OFDR Sensing System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Luna will team with Dr. John Bowers of UCSB to develop an Optical Frequency Domain Reflectometry (OFDR) system-on-chip using heterogeneous silicon photonics to...

  18. Novel Real-Time Flight Envelope Monitoring System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed innovation is an aircraft flight envelope monitoring system that will provide real-time in-cockpit estimations of aircraft flight envelope boundaries....

  19. Computational Models for Nonlinear Aeroelastic Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Clear Science Corp. and Duke University propose to develop and demonstrate a new and efficient computational method of modeling nonlinear aeroelastic systems. The...

  20. Advanced Radiative Emitters for Radioisotope Thermophotovoltaic Power Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Radioisotope Power Systems (RPS) are critical for future flagship exploration missions in space and on planetary surfaces. Small improvements in the RPS performance,...

  1. Advanced Control System Design for Hypersonic Vehicles, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Guidance and control system design for hypersonic vehicles is more challenging than their subsonic and supersonic counterparts. Some of these challenges are (i)...

  2. NDE for Ablative Thermal Protection Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This program addresses the need for non-destructive evaluation (NDE) methods for quality assessment and defect evaluation of thermal protection systems (TPS),...

  3. NDE for Ablative Thermal Protection Systems, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — This program addresses the need for non-destructive evaluation (NDE) methods for quality assessment and defect evaluation of thermal protection systems (TPS). Novel...

  4. Robust, Highly Scalable Solar Array System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Solar array systems currently under development are focused on near-term missions with designs optimized for the 30-50 kW power range. However, NASA has a vital...

  5. Uninhabited Traffic Management System Evaluator (UTME), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The key innovation of this effort is the development of an Uninhabited Aerial System (UAS) Traffic Manager Evaluator (UTME) specifically targeted at evaluating...

  6. Silver Ion Biocide Delivery System for Water Disinfection, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — U.S. space exploration missions have long considered returning to the Moon and exploration of Mars that challenge life support systems. For these long duration...

  7. Advanced On Board Inert Gas Generation System (OBBIGS), Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Valcor Engineering Corporation proposes to develop an advanced On Board Inert Gas Generation System, OBIGGS, for aircraft fuel tank inerting to prevent hazardous...

  8. Distributed Diagnosis, Prognosis and Recovery for Complex Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Complex space systems such as lunar habitats generate huge amounts of data. For example, the International Space Station (ISS) has over 250,000 individually...

  9. Advanced 3D Object Identification System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Optra will build an Advanced 3D Object Identification System utilizing three or more high resolution imagers spaced around a launch platform. Data from each imager...

  10. Long-Range Nondestructive Testing System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal is for the development of a long range, multi-point non-destructive system for the detection of subsurface flaws in metallic and composite materials of...

  11. Extremelly High Bandwidth Rad Hard Data Acquisition System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Analog-to-digital converters (ADCs) are the key components for digitizing high-speed analog data in modern data acquisition systems, which is a critical part of...

  12. Sensor Area Network for Integrated Systems Health Management, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The term Integrated Systems Health Management (ISHM) is used to describe a capability that focuses on determining the condition (health) of every element in a...

  13. A Surface-Mounted Rotor State Sensing System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — A surface-mounted instrumentation system for measuring rotor blade motions on rotorcraft, for use both in flight and in wind tunnel testing, is proposed for...

  14. Flexible and Safe Control of Mobile Surface Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The primary innovation of this work is a novel Petri net based approach for safe and flexible control of highly capable mobile surface systems, such as long-duration...

  15. Extreme Environment Sampling System Deployment Mechanism, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Future Venus or Comet mission architectures may feature robotic sampling systems comprised of a Sampling Tool and Deployment Mechanism. Since 2005, Honeybee has been...

  16. Low Mass Low Power Hall Thruster System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA is seeking electric propulsion systems capable of producing up to 20mN thrust, input power up to 1000W and specific impulse ranging from 1600-3500 seconds. The...

  17. Collaborative Object Framework for Adaptive System Optimization, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — TeamVision proposes that we research the feasibility of incorporating an adaptive object based optimization system into an existing multi-user object oriented...

  18. Miniaturized Airborne Imaging Central Server System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation is a miniaturized airborne imaging central server system (MAICSS). MAICSS is designed as a high-performance-computer-based electronic backend that...

  19. Miniaturized Airborne Imaging Central Server System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation is a miniaturized airborne imaging central server system (MAICSS). MAICSS is designed as a high-performance computer-based electronic backend that...

  20. The Vulcan Advanced Hybrid Manufacturing System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Made In Space is developing the The Vulcan Advanced Hybrid Manufacturing System (VULCAN) to address NASA's requirement to produce high-strength, high-precision...

  1. Multi-Purpose X-ray System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Stellarray proposes the development of a highly novel Multi-Purpose X-ray Source and System (MPXS), for use on flight missions, space stations, planetary excursions...

  2. Multi-Purpose X-ray System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed Multi-Purpose X-ray Source and System (MPXS) can be used on flight missions, space stations, planetary excursions and planetary or asteroid bases, to...

  3. Adaptive Venturi for Monopropellant Feed Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Physical Sciences Inc. proposes to develop a unique venturi for future monopropellant feed systems that uses a passively controlled throat area to adjust propellant...

  4. Integrated Fiber Optic Sensor and Modeling System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Advanced space fission systems are being developed as safe and affordable space propulsion alternatives for long-term space exploration. The characterization of...

  5. Anthony Pro - Human Automation Interaction in Aerospace Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposed project aims to demonstrate the feasibility and utility of a data mining system designed to facilitate the interpretation of information obtained from...

  6. Quantifiable and Reliable Structural Health Management Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Major concerns for implementing a practical built-in structural health monitoring system are prediction accuracy and data reliability. It is proposed to develop...

  7. Open System of Agile Ground Stations, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — There is an opportunity to build the HETE-2/TESS network of ground stations into an innovative and powerful Open System of Agile Stations, by developing a low-cost...

  8. Phase-chronometric measuring systems for the provision of technological processes and diagnostics of the production of electromechanical engineering systems

    Directory of Open Access Journals (Sweden)

    Tumakova Ekaterina

    2017-01-01

    Full Text Available In paper the main problems and objectives assessment of the current technical condition of the machine-building equipment are considered. Modern measuring systems used in engineering analysis. The paper considers a phase-chronometric information technology-metrological support for the evaluation of the technical condition of the synchronous electromechanical systems on the example of turbine CHP. Analysis of the main problems in the diagnosis of electromechanical systems is given. Phase-chronometric method as a basis for building a new system of diagnosis of electromechanical systems reviewed. The paper describes the main elements of technology, assessment of the economic effects of its introduction in the industry.

  9. Integrated thermal treatment system study: Phase 1 results. Volume 1

    International Nuclear Information System (INIS)

    Feizollahi, F.; Quapp, W.J.; Hempill, H.G.; Groffie, F.J.

    1994-07-01

    An integrated systems engineering approach is used for uniform comparison of widely varying thermal treatment technologies proposed for management of contact-handled mixed low-level waste (MLLW) currently stored in the US Department of Energy complex. Ten different systems encompassing several incineration design options are studied. All subsystems, including facilities, equipment, and methods needed for integration of each of the ten systems are identified. Typical subsystems needed for complete treatment of MLLW are incoming waste receiving and preparation (characterization, sorting, sizing, and separation), thermal treatment, air pollution control, primary and secondary stabilization, metal decontamination, metal melting, mercury recovery, lead recovery, and special waste and aqueous waste treatment. The evaluation is performed by developing a preconceptual design package and planning life-cycle cost (PLCC) estimates for each system. As part of the preconceptual design process, functional and operational requirements, flow sheets and mass balances, and conceptual equipment layouts are developed for each system. The PLCC components estimated are technology development, production facility construction, pre-operation, operation and maintenance, and decontamination and decommissioning. Preconceptual design data and other technology information gathered during the study are examined and areas requiring further development, testing, and evaluation are identified and recommended. Using a qualitative method, each of the ten systems are ranked

  10. Thermodynamic analysis of the two-phase ejector air-conditioning system for buses

    International Nuclear Information System (INIS)

    Ünal, Şaban; Yilmaz, Tuncay

    2015-01-01

    Air-conditioning compressors of the buses are usually operated with the power taken from the engine of the buses. Therefore, an improvement in the air-conditioning system will reduce the fuel consumption of the buses. The improvement in the coefficient of performance (COP) of the air-conditioning system can be provided by using the two-phase ejector as an expansion valve in the air-conditioning system. In this study, the thermodynamic analysis of bus air-conditioning system enhanced with a two-phase ejector and two evaporators is performed. Thermodynamic analysis is made assuming that the mixing process in ejector occurs at constant cross-sectional area and constant pressure. The increase rate in the COP with respect to conventional system is analyzed in terms of the subcooling, condenser and evaporator temperatures. The analysis shows that COP improvement of the system by using the two phase ejector as an expansion device is 15% depending on design parameters of the existing bus air-conditioning system. - Highlights: • Thermodynamic analysis of the two-phase ejector refrigeration system. • Analysis of the COP increase rate of bus air-conditioning system. • Analysis of the entrainment ratio of the two-phase ejector refrigeration system

  11. Competing failure analysis in phased-mission systems with multiple functional dependence groups

    International Nuclear Information System (INIS)

    Wang, Chaonan; Xing, Liudong; Peng, Rui; Pan, Zhusheng

    2017-01-01

    A phased-mission system (PMS) involves multiple, consecutive, non-overlapping phases of operation. The system structure function and component failure behavior in a PMS can change from phase to phase, posing big challenges to the system reliability analysis. Further complicating the problem is the functional dependence (FDEP) behavior where the failure of certain component(s) causes other component(s) to become unusable or inaccessible or isolated. Previous studies have shown that FDEP can cause competitions between failure propagation and failure isolation in the time domain. While such competing failure effects have been well addressed in single-phase systems, only little work has focused on PMSs with a restrictive assumption that a single FDEP group exists in one phase of the mission. Many practical systems (e.g., computer systems and networks), however may involve multiple FDEP groups during the mission. Moreover, different FDEP groups can be dependent due to sharing some common components; they may appear in a single phase or multiple phases. This paper makes new contributions by modeling and analyzing reliability of PMSs subject to multiple FDEP groups through a Markov chain-based methodology. Propagated failures with both global and selective effects are considered. Four case studies are presented to demonstrate application of the proposed method. - Highlights: • Reliability of phased-mission systems subject to competing failure propagation and isolation effects is modeled. • Multiple independent or dependent functional dependence groups are considered. • Propagated failures with global effects and selective effects are studied. • Four case studies demonstrate generality and application of the proposed Markov-based method.

  12. Experimental study on the phase equilibria of the Ag-Ti system

    International Nuclear Information System (INIS)

    Fu Xiaoliang; Li Changrong; Wang Fuming; Li Mei; Zhang Weijing

    2005-01-01

    The Ag-Ti diffusion couples were prepared by small pure silver plates closely packed in pure titanium powder, sealed in quartz tube, and annealed at 750 deg. C, 980 deg. C, 1100 deg. C and 1200 deg. C, respectively. The phase equilibrium relationship and the conjugate phase compositions in the Ag-Ti system were determined by means of the metallographic microscope and the electron probe microanalysis. Partial liquidus and solidus for the two-phase equilibrium, liquid + (βTi), were obtained. The narrow solution range for the intermediate phase (TiAg) was determined

  13. Virtual Design of a Controller for a Hydraulic Cam Phasing System

    Science.gov (United States)

    Schneider, Markus; Ulbrich, Heinz

    2010-09-01

    Hydraulic vane cam phasing systems are nowadays widely used for improving the performance of combustion engines. At stationary operation, these systems should achieve a constant phasing angle, which however is badly disturbed by the alternating torque generated by the valve actuation. As the hydraulic system shows a non-linear characteristic over the full operation range and the inductivity of the hydraulic pipes generates a significant time delay, a full model based control emerges very complex. Therefore a simple feed-forward controller is designed, bridging the time delay of the hydraulic system and improving the system behaviour significantly.

  14. Model and Frequency Control for Three-Phase Wireless Power Transfer System

    Directory of Open Access Journals (Sweden)

    Chenyang Xia

    2016-01-01

    Full Text Available In order to the eliminate the “dead spot” in the traditional three-phase wireless power transfer (WPT system, a three-phase WPT system with an asymmetric magnetic circuit is presented in this paper. Additionally, mathematical model of the system is established and the system parameters are optimized. Based on the fact that the resonant frequency and efficiency are greatly varied with the load, a method based on impedance conversion is further proposed to improve the frequency stability and system efficiency. Finally, simulation and experimental results show that the proposed method is reliable and feasible to eliminate the “dead spot.”

  15. Dynamic Isotope Power System: technology verification phase, program plan, 1 October 1978

    International Nuclear Information System (INIS)

    1979-01-01

    The technology verification phase program plan of the Dynamic Isotope Power System (DIPS) project is presented. DIPS is a project to develop a 0.5 to 2.0 kW power system for spacecraft using an isotope heat source and a closed-cycle Rankine power-system with an organic working fluid. The technology verification phase's purposes are to increase the system efficiency to over 18%, to demonstrate system reliability, and to provide an estimate for flight test scheduling. Progress toward these goals is reported

  16. Non-Parametric, Closed-Loop Testing of Autonomy in Unmanned Aircraft Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed Phase I program aims to develop new methods to support safety testing for integration of Unmanned Aircraft Systems into the National Airspace (NAS) with...

  17. Live Fire Evaluation of the Expeditionary Fire Suppression System (EFSS); Phase I

    National Research Council Canada - National Science Library

    Kalberer, Jennifer

    2004-01-01

    .... The system uses AFFF-based compressed air foam and PKP dry chemical. Phase I evaluated the effectiveness of the modified-commercially available EFSS on live fires on static pool and running fuel fires...

  18. Improved Rock Core Sample Break-off, Retention and Ejection System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed effort advances the design of an innovative core sampling and acquisition system with improved core break-off, retention and ejection features. Phase 1...

  19. Thermodynamics and phase equilibria of ternary systems relevant to contact materials for compound semiconductors

    International Nuclear Information System (INIS)

    Ipser, H.; Richter, K.; Micke, K.

    1997-01-01

    In order to investigate the stability of ohmic contacts to compound semiconductors, it is necessary to know the phase equilibria in the corresponding multi-component systems. We are currently studying the phase equilibria and thermophysical properties of several ternary systems which are of interest in view of the use of nickel, palladium and platinum as contact materials for GaSb and InSb compound semiconductors: Ga-Ni-Sb, In-Ni-Sb, Ga-Pd-Sb and Ga-Pt-Sb. Phase equilibria are investigated by thermal analyses, X-ray powder diffraction methods as well as electron microprobe analysis. Thermodynamic properties are derived from vapour pressure measurements using an isopiestic method. It is planned to combine all information on phase equilibria and thermochemistry for the ternary and the limiting binary systems to perform an optimization of the ternary systems by computer calculations using standard software. (author)

  20. Solid State Transmitters for Water Vapor and Ozone DIAL Systems, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The focus of this Select Phase II program is to build and deliver laser components both for airborne water vapor and ozone DIAL systems. Specifically, Fibertek...