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Sample records for pseudorandom binary sequence

  1. Generation and application of pseudorandom binary sequences using virtual instrumentation

    OpenAIRE

    Miljković, Goran S.; Stojković, Ivana S.; Denić, Dragan B.

    2011-01-01

    A very dynamical development of virtual instrumentation in recent years has caused a very good acceptance of this concept and its use in many applications. This concept, as one flexible and cost-effective solution for test and measurement, is used in this paper for implementation and application of maximum length pseudorandom binary sequences generator. Because of their properties, the pseudorandom binary sequences are often used in development and improvement of modern pseudorandom position ...

  2. Design of pseudorandom binary sequence generator using lithium-niobate-based Mach-Zehnder interferometers

    Science.gov (United States)

    Choudhary, Kuldeep; Kumar, Santosh

    2017-05-01

    The application of electro-optic effect in lithium-niobate-based Mach-Zehnder interferometer to design a 3-bit optical pseudorandom binary sequence (PRBS) generator has been proposed, which is characterized by its simplicity of generation and stability. The proposed device is optoelectronic in nature. The PBRS generator is immensely applicable for pattern generation, encryption, and coding applications in optical networks. The study is carried out by simulating the proposed device with beam propagation method.

  3. Cardiorespiratory Kinetics Determined by Pseudo-Random Binary Sequences - Comparisons between Walking and Cycling.

    Science.gov (United States)

    Koschate, J; Drescher, U; Thieschäfer, L; Heine, O; Baum, K; Hoffmann, U

    2016-12-01

    This study aims to compare cardiorespiratory kinetics as a response to a standardised work rate protocol with pseudo-random binary sequences between cycling and walking in young healthy subjects. Muscular and pulmonary oxygen uptake (V̇O2) kinetics as well as heart rate kinetics were expected to be similar for walking and cycling. Cardiac data and V̇O2 of 23 healthy young subjects were measured in response to pseudo-random binary sequences. Kinetics were assessed applying time series analysis. Higher maxima of cross-correlation functions between work rate and the respective parameter indicate faster kinetics responses. Muscular V̇O2 kinetics were estimated from heart rate and pulmonary V̇O2 using a circulatory model. Muscular (walking vs. cycling [mean±SD in arbitrary units]: 0.40±0.08 vs. 0.41±0.08) and pulmonary V̇O2 kinetics (0.35±0.06 vs. 0.35±0.06) were not different, although the time courses of the cross-correlation functions of pulmonary V̇O2 showed unexpected biphasic responses. Heart rate kinetics (0.50±0.14 vs. 0.40±0.14; P=0.017) was faster for walking. Regarding the biphasic cross-correlation functions of pulmonary V̇O2 during walking, the assessment of muscular V̇O2 kinetics via pseudo-random binary sequences requires a circulatory model to account for cardio-dynamic distortions. Faster heart rate kinetics for walking should be considered by comparing results from cycle and treadmill ergometry. © Georg Thieme Verlag KG Stuttgart · New York.

  4. Analysis of heart rate and oxygen uptake kinetics studied by two different pseudo-random binary sequence work rate amplitudes.

    Science.gov (United States)

    Drescher, U; Koschate, J; Schiffer, T; Schneider, S; Hoffmann, U

    2017-06-01

    The aim of the study was to compare the kinetics responses of heart rate (HR), pulmonary (V˙O2pulm) and predicted muscular (V˙O2musc) oxygen uptake between two different pseudo-random binary sequence (PRBS) work rate (WR) amplitudes both below anaerobic threshold. Eight healthy individuals performed two PRBS WR protocols implying changes between 30W and 80W and between 30W and 110W. HR and V˙O2pulm were measured beat-to-beat and breath-by-breath, respectively. V˙O2musc was estimated applying the approach of Hoffmann et al. (Eur J Appl Physiol 113: 1745-1754, 2013) considering a circulatory model for venous return and cross-correlation functions (CCF) for the kinetics analysis. HR and V˙O2musc kinetics seem to be independent of WR intensity (p>0.05). V˙O2pulm kinetics show prominent differences in the lag of the CCF maximum (39±9s; 31±4s; pkinetics remain unchanged. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Cryptographic pseudo-random sequences from the chaotic Hénon ...

    Indian Academy of Sciences (India)

    Pseudo-random number sequences are useful in many applications including Monte-Carlo simulation, spread spectrum ... a pseudo-random binary sequence from the two-dimensional chaotic Hénon map is explored. ... is the Hénon map, a two-dimensional discrete-time nonlinear dynamical system represented by the state ...

  6. Synchronizing microelectrode and electronic goniometer data using a pseudo-random binary signal.

    Science.gov (United States)

    Moore, Tyler Robert; Jacobs, Rennie Underwood; Yang, Alexander Cheung; Richter, Erich Oscar

    2013-04-01

    Intra-operative investigation of the subthalamic nucleus (STN) requires concurrent measurement of microelectrode voltage, electrode depth and joint movement during deep brain stimulation (DBS) surgery. Commercial solutions to this problem exist but are more expensive. Multiple instruments from different manufacturers can collect the same data, but data from incompatible instruments are collected on disparate clocks, precluding quantitative analysis. A pseudo-random binary signal recorded simultaneously by each set of instruments allows for chronological reconciliation. A custom program collects microelectrode data while simultaneously sending a pseudo-random binary signal to instruments measuring joint movement. The record of this signal is later used to express microelectrode voltage and joint position in a single chronological frame of reference. ClockSynch was used in 15 DBS procedures. After each surgery, records of microelectrode and joint movement were successfully chronologically reconciled. In conclusion, a pseudo-random binary signal integrates disparate systems of instrumentation at a significantly decreased cost.

  7. Optimal pseudorandom sequence selection for online c-VEP based BCI control applications

    DEFF Research Database (Denmark)

    Isaksen, Jonas L.; Mohebbi, Ali; Puthusserypady, Sadasivan

    2017-01-01

    Background: In a c-VEP BCI setting, test subjects can have highly varying performances when different pseudorandom sequences are applied as stimulus, and ideally, multiple codes should be supported. On the other hand, repeating the experiment with many different pseudorandom sequences is a labori......Background: In a c-VEP BCI setting, test subjects can have highly varying performances when different pseudorandom sequences are applied as stimulus, and ideally, multiple codes should be supported. On the other hand, repeating the experiment with many different pseudorandom sequences...... predictor. Conclusions: The simple and fast method presented in this study as the Accuracy Score, allows c-VEP based BCI systems to support multiple pseudorandom sequences without increase in trial length. This allows for more personalized BCI systems with better performance to be tested without increased...

  8. Calibration of Modulation Transfer Function of Surface Profilometers with 1D and 2D Binary Pseudo-random Array Standards

    Energy Technology Data Exchange (ETDEWEB)

    Yashchuk, Valeriy V.; McKinney, Wayne R.; Takacs, Peter Z.

    2008-05-19

    We suggest and describe the use of a binary pseudo-random grating as a standard test surface for calibration of the modulation transfer function of microscopes. Results from calibration of a MicromapTM-570 interferometric microscope are presented.

  9. Method for Generating Pseudorandom Sequences with the Assured Period Based on R-blocks

    Directory of Open Access Journals (Sweden)

    M. A. Ivanov

    2011-03-01

    Full Text Available The article describes the characteristics of a new class of fast-acting pseudorandom number generators, based on the use of stochastic adders or R-blocks. A new method for generating pseudorandom sequences with the assured length of period is offered.

  10. Characterization of Electron Microscopes with Binary Pseudo-random Multilayer Test Samples

    Energy Technology Data Exchange (ETDEWEB)

    V Yashchuk; R Conley; E Anderson; S Barber; N Bouet; W McKinney; P Takacs; D Voronov

    2011-12-31

    Verification of the reliability of metrology data from high quality X-ray optics requires that adequate methods for test and calibration of the instruments be developed. For such verification for optical surface profilometers in the spatial frequency domain, a modulation transfer function (MTF) calibration method based on binary pseudo-random (BPR) gratings and arrays has been suggested [1] and [2] and proven to be an effective calibration method for a number of interferometric microscopes, a phase shifting Fizeau interferometer, and a scatterometer [5]. Here we describe the details of development of binary pseudo-random multilayer (BPRML) test samples suitable for characterization of scanning (SEM) and transmission (TEM) electron microscopes. We discuss the results of TEM measurements with the BPRML test samples fabricated from a WiSi2/Si multilayer coating with pseudo-randomly distributed layers. In particular, we demonstrate that significant information about the metrological reliability of the TEM measurements can be extracted even when the fundamental frequency of the BPRML sample is smaller than the Nyquist frequency of the measurements. The measurements demonstrate a number of problems related to the interpretation of the SEM and TEM data. Note that similar BPRML test samples can be used to characterize X-ray microscopes. Corresponding work with X-ray microscopes is in progress.

  11. Characterization of electron microscopes with binary pseudo-random multilayer test samples

    Energy Technology Data Exchange (ETDEWEB)

    Yashchuk, Valeriy V., E-mail: VVYashchuk@lbl.gov [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Conley, Raymond [NSLS-II, Brookhaven National Laboratory, Upton, NY 11973 (United States); Anderson, Erik H. [Center for X-ray Optics, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Barber, Samuel K. [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Bouet, Nathalie [NSLS-II, Brookhaven National Laboratory, Upton, NY 11973 (United States); McKinney, Wayne R. [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Takacs, Peter Z. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Voronov, Dmitriy L. [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2011-09-01

    Verification of the reliability of metrology data from high quality X-ray optics requires that adequate methods for test and calibration of the instruments be developed. For such verification for optical surface profilometers in the spatial frequency domain, a modulation transfer function (MTF) calibration method based on binary pseudo-random (BPR) gratings and arrays has been suggested and proven to be an effective calibration method for a number of interferometric microscopes, a phase shifting Fizeau interferometer, and a scatterometer [5]. Here we describe the details of development of binary pseudo-random multilayer (BPRML) test samples suitable for characterization of scanning (SEM) and transmission (TEM) electron microscopes. We discuss the results of TEM measurements with the BPRML test samples fabricated from a WiSi{sub 2}/Si multilayer coating with pseudo-randomly distributed layers. In particular, we demonstrate that significant information about the metrological reliability of the TEM measurements can be extracted even when the fundamental frequency of the BPRML sample is smaller than the Nyquist frequency of the measurements. The measurements demonstrate a number of problems related to the interpretation of the SEM and TEM data. Note that similar BPRML test samples can be used to characterize X-ray microscopes. Corresponding work with X-ray microscopes is in progress.

  12. Binary Pseudo-Random Gratings and Arrays for Calibration of Modulation Transfer Functions of Surface Profilometers

    Energy Technology Data Exchange (ETDEWEB)

    Barber, Samuel K.; Anderson, Erik D.; Cambie, Rossana; McKinney, Wayne R.; Takacs, Peter Z.; Stover, John C.; Voronov, Dmitriy L.; Yashchuk, Valeriy V.

    2009-09-11

    A technique for precise measurement of the modulation transfer function (MTF), suitable for characterization of a broad class of surface profilometers, is investigated in detail. The technique suggested in [Proc. SPIE 7077-7, (2007), Opt. Eng. 47(7), 073602-1-5 (2008)]is based on use of binary pseudo-random (BPR) gratings and arrays as standard MTF test surfaces. Unlike most conventional test surfaces, BPR gratings and arrays possess white-noise-like inherent power spectral densities (PSD), allowing the direct determination of the one- and two-dimensional MTF, respectively, with a sensitivity uniform over the entire spatial frequency range of a profiler. In the cited work, a one dimensional realization of the suggested method based on use of BPR gratings has been demonstrated. Here, a high-confidence of the MTF calibration technique is demonstrated via cross comparison measurements of a number of two dimensional BPR arrays using two different interferometric microscopes and a scatterometer. We also present the results of application of the experimentally determined MTF correction to the measurement taken with the MicromapTM-570 interferometric microscope of the surface roughness of a super-polished test mirror. In this particular case, without accounting for the instrumental MTF, the surface rms roughness over half of the instrumental spatial frequency bandwidth would be underestimated by a factor of approximately 1.4.

  13. Design of Long Period Pseudo-Random Sequences from the Addition of m -Sequences over 𝔽 p

    Directory of Open Access Journals (Sweden)

    Ren Jian

    2004-01-01

    Full Text Available Pseudo-random sequence with good correlation property and large linear span is widely used in code division multiple access (CDMA communication systems and cryptology for reliable and secure information transmission. In this paper, sequences with long period, large complexity, balance statistics, and low cross-correlation property are constructed from the addition of m -sequences with pairwise-prime linear spans (AMPLS. Using m -sequences as building blocks, the proposed method proved to be an efficient and flexible approach to construct long period pseudo-random sequences with desirable properties from short period sequences. Applying the proposed method to 𝔽 2 , a signal set ( ( 2 n − 1 ( 2 m − 1 , ( 2 n + 1 ( 2 m + 1 , ( 2 ( n + 1 / 2 + 1 ( 2 ( m + 1 / 2 + 1 is constructed.

  14. Development of Pseudorandom Binary Arrays for Calibration of Surface Profile Metrology Tools

    Energy Technology Data Exchange (ETDEWEB)

    Barber, S.K.; Takacs, P.; Soldate, P.; Anderson, E.H.; Cambie, R.; McKinney, W.R.; Voronov, D.L.; Yashchuk, V.V.

    2009-12-01

    measured and simulated PSD distributions gives the MTF of the instrument. The applicability of the MTF concept to phase map measurements with optical interferometric microscopes needs to be experimentally verified as the optical tool and algorithms may introduce nonlinear artifacts into the process. In previous work [V. V. Yashchuk et al., Proc. SPIE 6704, 670408 (2007); Valeriy V. Yashchuk et al., Opt. Eng. (Bellingham) 47, 073602 (2008)] the instrumental MTF of a surface profiler was precisely measured using reference test surfaces based on binary pseudorandom (BPR) gratings. Here, the authors present results of fabricating and using two-dimensional (2D) BPR arrays that allow for a direct 2D calibration of the instrumental MTF. BPR sequences are widely used in engineering and communication applications such as global position systems and wireless communication protocols. The ideal BPR pattern has a flat 'white noise' response over the entire range of spatial frequencies of interest. The BPR array used here is based on the uniformly redundant array (URA) prescription [E. E. Fenimore and T. M. Cannon, Appl. Opt. 17, 337 (1978)] initially used for x-ray and gamma ray astronomy applications. The URA's superior imaging capability originates from the fact that its cyclical autocorrelation function very closely approximates a delta function, which produces a flat PSD. Three different size BPR array patterns were fabricated by electron beam lithography and induction coupled plasma etching of silicon. The basic size units were 200, 400, and 600 nm. Two different etch processes were used, CF{sub 4}/Ar and HBr, which resulted in undercut and vertical sidewall profiles, respectively. The 2D BPR arrays were used as standard test surfaces for MTF calibration of the MicroMap{trademark}-570 interferometric microscope using all available objectives. The MicroMap{trademark}-570 interferometric microscope uses incoherent illumination from a tungsten filament source and

  15. Characterization of an Acoustic Communication Channel with Pseudorandom Binary Sequences

    NARCIS (Netherlands)

    Walree, P.A. van; Bertolotto, G.

    2007-01-01

    The joint European project "UUV Covert Acoustic Communications" explores methods for underwater communication at low signal-to-noise ratios. The first phase of the project focuses on characterization of the communication channel. Sea trials were conducted in two littoral environments in September

  16. Binary pseudo-random grating as a standard test surface formeasurement of modulation transfer function of interferometricmicroscopes

    Energy Technology Data Exchange (ETDEWEB)

    Yashchuk, Valeriy V.; McKinney, Wayne R.; Takacs, Peter Z.

    2007-07-25

    The task of designing high performance X-ray optical systemsrequires the development of sophisticated X-ray scattering calculationsbased on rigorous information about the optics. One of the mostinsightful approaches to these calculations is based on the powerspectral density (PSD) distribution of the surface height. The majorproblem of measurement of a PSD distribution with an interferometricand/or atomic force microscope arises due to the unknown ModulationTransfer Function (MTF) of the instruments. The MTF characterizes theperturbation of the PSD distribution at higher spatial frequencies. Here,we describe a new method and dedicated test surfaces for calibration ofthe MTF of a microscope. The method is based on use of a speciallydesigned Binary Pseudo-random (BPR) grating. Comparison of atheoretically calculated PSD spectrum of a BPR grating with a spectrummeasured with the grating provides the desired calibration of theinstrumental MTF. The theoretical background of the method, as well asresults of experimental investigations are presented.

  17. A comparative study of pseudorandom sequences used in a c-VEP based BCI for online wheelchair control

    DEFF Research Database (Denmark)

    Isaksen, Jonas L.; Mohebbi, Ali; Puthusserypady, Sadasivan

    2016-01-01

    In this study, a c-VEP based BCI system was developed to run on three distinctive pseudorandom sequences, namely the m-code, the Gold-code, and the Barker-code. The Visual Evoked Potentials (VEPs) were provoked using these codes. In the online session, subjects controlled a LEGO® Mindstorms® robot...

  18. Pseudorandom Bit Sequence Generator for Stream Cipher Based on Elliptic Curves

    Directory of Open Access Journals (Sweden)

    Jilna Payingat

    2015-01-01

    Full Text Available This paper proposes a pseudorandom sequence generator for stream ciphers based on elliptic curves (EC. A detailed analysis of various EC based random number generators available in the literature is done and a new method is proposed such that it addresses the drawbacks of these schemes. Statistical analysis of the proposed method is carried out using the NIST (National Institute of Standards and Technology test suite and it is seen that the sequence exhibits good randomness properties. The linear complexity analysis shows that the system has a linear complexity equal to the period of the sequence which is highly desirable. The statistical complexity and security against known plain text attack are also analysed. A comparison of the proposed method with other EC based schemes is done in terms of throughput, periodicity, and security, and the proposed method outperforms the methods in the literature. For resource constrained applications where a highly secure key exchange is essential, the proposed method provides a good option for encryption by time sharing the point multiplication unit for EC based key exchange. The algorithm and architecture for implementation are developed in such a way that the hardware consumed in addition to point multiplication unit is much less.

  19. Stability of modulation transfer function calibration of surface profilometers using binary pseudo-random gratings and arrays with nonideal groove shapes

    Energy Technology Data Exchange (ETDEWEB)

    Barber, Samuel K.; Anderson, Erik H.; Cambie, Rossana; Marchesini, Stefano; McKinney, Wayne R.; Takacs, Peter Z.; Voronov, Dmitry L.; Yashchuk, Valeriy V.

    2010-03-31

    The major problem of measurement of a power spectral density (PSD) distribution of surface heights with surface profilometers arises due to the unknown Modulation Transfer Function (MTF) of the instruments, which tends to distort the PSD at higher spatial frequencies. The special mathematical properties of binary pseudo-random patterns make them an ideal basis for developing MTF calibration test surfaces. Two-dimensional binary pseudo-random arrays (BPRAs) have been fabricated and used for the MTF calibration of the MicroMap{trademark}-570 interferometric microscope with all available objectives. An investigation into the effects of fabrication imperfections on the quality of the MTF calibration and a procedure for accounting for such imperfections are presented.

  20. Pseudorandom number generation using chaotic true orbits of the Bernoulli map

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Asaki, E-mail: saito@fun.ac.jp [Future University Hakodate, 116-2 Kamedanakano-cho, Hakodate, Hokkaido 041-8655 (Japan); Yamaguchi, Akihiro [Fukuoka Institute of Technology, 3-30-1 Wajiro-higashi, Higashi-ku, Fukuoka 811-0295 (Japan)

    2016-06-15

    We devise a pseudorandom number generator that exactly computes chaotic true orbits of the Bernoulli map on quadratic algebraic integers. Moreover, we describe a way to select the initial points (seeds) for generating multiple pseudorandom binary sequences. This selection method distributes the initial points almost uniformly (equidistantly) in the unit interval, and latter parts of the generated sequences are guaranteed not to coincide. We also demonstrate through statistical testing that the generated sequences possess good randomness properties.

  1. Quasi-Coherent Noise Jamming to LFM Radar Based on Pseudo-random Sequence Phase-modulation

    Directory of Open Access Journals (Sweden)

    N. Tai

    2015-12-01

    Full Text Available A novel quasi-coherent noise jamming method is proposed against linear frequency modulation (LFM signal and pulse compression radar. Based on the structure of digital radio frequency memory (DRFM, the jamming signal is acquired by the pseudo-random sequence phase-modulation of sampled radar signal. The characteristic of jamming signal in time domain and frequency domain is analyzed in detail. Results of ambiguity function indicate that the blanket jamming effect along the range direction will be formed when jamming signal passes through the matched filter. By flexible controlling the parameters of interrupted-sampling pulse and pseudo-random sequence, different covering distances and jamming effects will be achieved. When the jamming power is equivalent, this jamming obtains higher process gain compared with non-coherent jamming. The jamming signal enhances the detection threshold and the real target avoids being detected. Simulation results and circuit engineering implementation validate that the jamming signal covers real target effectively.

  2. Calibration of the Modulation Transfer Function of Surface Profilometers with Binary Pseudorandom Test Standards: Expanding the Application Range to Fizeau Interferometers and Electron Microscopes

    Energy Technology Data Exchange (ETDEWEB)

    Yashchuk, V.V.; Takacs, P.; Anderson, E.H.; Barber, S.K.; Bouet, N.; Cambie, R.; Conley, R.; McKinney, W.R.; Voronov, D.L.

    2011-09-16

    A modulation transfer function (MTF) calibration method based on binary pseudorandom (BPR) gratings and arrays has been proven to be an effective MTF calibration method for interferometric microscopes and a scatterometer. Here we report on a further expansion of the application range of the method. We describe the MTF calibration of a 6 in. phase shifting Fizeau interferometer. Beyond providing a direct measurement of the interferometer's MTF, tests with a BPR array surface have revealed an asymmetry in the instrument's data processing algorithm that fundamentally limits its bandwidth. Moreover, the tests have illustrated the effects of the instrument's detrending and filtering procedures on power spectral density measurements. The details of the development of a BPR test sample suitable for calibration of scanning and transmission electron microscopes are also presented. Such a test sample is realized as a multilayer structure with the layer thicknesses of two materials corresponding to the BPR sequence. The investigations confirm the universal character of the method that makes it applicable to a large variety of metrology instrumentation with spatial wavelength bandwidths from a few nanometers to hundreds of millimeters.

  3. Binary pseudo-random patterned structures for modulation transfer function calibration and resolution characterization of a full-field transmission soft x-ray microscope

    Energy Technology Data Exchange (ETDEWEB)

    Yashchuk, V. V., E-mail: VVYashchuk@lbl.gov; Chan, E. R.; Lacey, I. [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Fischer, P. J. [Center for X-Ray Optics, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Physics Department, University of California Santa Cruz, Santa Cruz, California 94056 (United States); Conley, R. [Advance Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973 (United States); McKinney, W. R. [Diablo Valley College, 321 Golf Club Road, Pleasant Hill, California 94523 (United States); Artemiev, N. A. [KLA-Tencor Corp., 1 Technology Drive, Milpitas, California 95035 (United States); Bouet, N. [National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973 (United States); Cabrini, S. [Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Calafiore, G.; Peroz, C.; Babin, S. [aBeam Technologies, Inc., Hayward, California 94541 (United States)

    2015-12-15

    We present a modulation transfer function (MTF) calibration method based on binary pseudo-random (BPR) one-dimensional sequences and two-dimensional arrays as an effective method for spectral characterization in the spatial frequency domain of a broad variety of metrology instrumentation, including interferometric microscopes, scatterometers, phase shifting Fizeau interferometers, scanning and transmission electron microscopes, and at this time, x-ray microscopes. The inherent power spectral density of BPR gratings and arrays, which has a deterministic white-noise-like character, allows a direct determination of the MTF with a uniform sensitivity over the entire spatial frequency range and field of view of an instrument. We demonstrate the MTF calibration and resolution characterization over the full field of a transmission soft x-ray microscope using a BPR multilayer (ML) test sample with 2.8 nm fundamental layer thickness. We show that beyond providing a direct measurement of the microscope’s MTF, tests with the BPRML sample can be used to fine tune the instrument’s focal distance. Our results confirm the universality of the method that makes it applicable to a large variety of metrology instrumentation with spatial wavelength bandwidths from a few nanometers to hundreds of millimeters.

  4. Permutation Entropy for Random Binary Sequences

    Directory of Open Access Journals (Sweden)

    Lingfeng Liu

    2015-12-01

    Full Text Available In this paper, we generalize the permutation entropy (PE measure to binary sequences, which is based on Shannon’s entropy, and theoretically analyze this measure for random binary sequences. We deduce the theoretical value of PE for random binary sequences, which can be used to measure the randomness of binary sequences. We also reveal the relationship between this PE measure with other randomness measures, such as Shannon’s entropy and Lempel–Ziv complexity. The results show that PE is consistent with these two measures. Furthermore, we use PE as one of the randomness measures to evaluate the randomness of chaotic binary sequences.

  5. Optical 10-20 and 20-40 Gbits/s pseudorandom bit sequence data multiplexing utilizing conversion-dispersion-based tunable optical delays.

    Science.gov (United States)

    Wu, Xiaoxia; Christen, Louis; Yilmaz, Omer F; Nuccio, Scott R; Willner, Alan E

    2008-07-01

    We experimentally demonstrate all-optical 2(7)-1 pseudorandom bit sequence data multiplexing using wavelength conversion, interchannel chromatic dispersion, and intrachannel dispersion compensation. Bit-rate tuning capability is demonstrated with 10-20 and 20-40 Gbits/s multiplexing, achieving a bit-error rate <10(-9) for both rates.

  6. Bit-rate-variable and order-switchable optical multiplexing of high-speed pseudorandom bit sequence using optical delays.

    Science.gov (United States)

    Wu, Xiaoxia; Wang, Jian; Yilmaz, Omer F; Nuccio, Scott R; Bogoni, Antonella; Willner, Alan E

    2010-09-15

    We experimentally demonstrate high-speed optical pseudorandom bit sequence (PRBS) multiplexing with coarse and fine bit-rate tuning capability and a switchable order using optical delays. Data multiplexing of 80 Gbit/s and 160 Gbit/s is shown, each with a tunable rate using a conversion/dispersion-based continuously tunable optical delay and tunable PRBS order with large switchable fiber delays. A 7% bit-rate tunability, i.e., 80-85.6 Gbit/s and 160-171.2 Gbit/s, is shown for both 2(7)-1 and 2(15)-1 PRBS. The rf spectra before and after multiplexing are measured in each case and show a suppression ratio of >30 dB, exhibiting the expected PRBS spectral characteristics.

  7. What's Next? Judging Sequences of Binary Events

    Science.gov (United States)

    Oskarsson, An T.; Van Boven, Leaf; McClelland, Gary H.; Hastie, Reid

    2009-01-01

    The authors review research on judgments of random and nonrandom sequences involving binary events with a focus on studies documenting gambler's fallacy and hot hand beliefs. The domains of judgment include random devices, births, lotteries, sports performances, stock prices, and others. After discussing existing theories of sequence judgments,…

  8. Cryptographic pseudo-random sequences from the chaotic Hénon ...

    Indian Academy of Sciences (India)

    dimensional discrete-time Hénon map is proposed. Properties of the proposed sequences pertaining to linear complexity, linear complexity profile, correlation and auto-correlation are investigated. All these properties of the sequences suggest a ...

  9. A measurement of disorder in binary sequences

    Science.gov (United States)

    Gong, Longyan; Wang, Haihong; Cheng, Weiwen; Zhao, Shengmei

    2015-03-01

    We propose a complex quantity, AL, to characterize the degree of disorder of L-length binary symbolic sequences. As examples, we respectively apply it to typical random and deterministic sequences. One kind of random sequences is generated from a periodic binary sequence and the other is generated from the logistic map. The deterministic sequences are the Fibonacci and Thue-Morse sequences. In these analyzed sequences, we find that the modulus of AL, denoted by |AL | , is a (statistically) equivalent quantity to the Boltzmann entropy, the metric entropy, the conditional block entropy and/or other quantities, so it is a useful quantitative measure of disorder. It can be as a fruitful index to discern which sequence is more disordered. Moreover, there is one and only one value of |AL | for the overall disorder characteristics. It needs extremely low computational costs. It can be easily experimentally realized. From all these mentioned, we believe that the proposed measure of disorder is a valuable complement to existing ones in symbolic sequences.

  10. A General Construction of Binary Sequences with Optimal Autocorrelation

    OpenAIRE

    Yan, Tongjiang; Chen, Zhixiong; Li, Bao

    2014-01-01

    A general construction of binary sequences with low autocorrelation are considered in the paper. Based on recent progresses about this topic and this construction, several classes of binary sequences with optimal autocorrelation and other low autocorrelation are presented.

  11. Minimum degree and density of binary sequences

    DEFF Research Database (Denmark)

    Brandt, Stephan; Müttel, J.; Rautenbach, D.

    2010-01-01

    For d,k∈N with k ≤ 2d, let g(d,k) denote the infimum density of binary sequences (x)∈{0,1} which satisfy the minimum degree condition σ(x+) ≥ k for all i∈Z with xi=1. We reduce the problem of computing g(d,k) to a combinatorial problem related to the generalized k-girth of a graph G which...

  12. Pseudorandomness in Central Force Optimization

    OpenAIRE

    Formato, Richard A.

    2010-01-01

    Central Force Optimization is a deterministic metaheuristic for an evolutionary algorithm that searches a decision space by flying probes whose trajectories are computed using a gravitational metaphor. CFO benefits substantially from the inclusion of a pseudorandom component (a numerical sequence that is precisely known by specification or calculation but otherwise arbitrary). The essential requirement is that the sequence is uncorrelated with the decision space topology, so that its effect i...

  13. Analyzing Influenza Virus Sequences using Binary Encoding Approach

    Directory of Open Access Journals (Sweden)

    Ham Ching Lam

    2012-01-01

    Full Text Available Capturing mutation patterns of each individual influenza virus sequence is often challenging; in this paper, we demonstrated that using a binary encoding scheme coupled with dimension reduction technique, we were able to capture the intrinsic mutation pattern of the virus. Our approach looks at the variance between sequences instead of the commonly used p-distance or Hamming distance. We first convert the influenza genetic sequences to a binary strings and form a binary sequence alignment matrix and then apply Principal Component Analysis (PCA to this matrix. PCA also provides identification power to identify reassortant virus by using data projection technique. Due to the sparsity of the binary string, we were able to analyze large volume of influenza sequence data in a very short time. For protein sequences, our scheme also allows the incorporation of biophysical properties of each amino acid. Here, we present various encouraging results from analyzing influenza nucleotide, protein and genome sequences using the proposed approach.

  14. Alternation Blindness in the Representation of Binary Sequences.

    Science.gov (United States)

    Yu, Ru Qi; Osherson, Daniel; Zhao, Jiaying

    2017-08-17

    Binary information is prevalent in the environment and contains 2 distinct outcomes. Binary sequences consist of a mixture of alternation and repetition. Understanding how people perceive such sequences would contribute to a general theory of information processing. In this study, we examined how people process alternation and repetition in binary sequences. Across 4 paradigms involving estimation, working memory, change detection, and visual search, we found that the number of alternations is underestimated compared with repetitions (Experiment 1). Moreover, recall for binary sequences deteriorates as the sequence alternates more (Experiment 2). Changes in bits are also harder to detect as the sequence alternates more (Experiment 3). Finally, visual targets superimposed on bits of a binary sequence take longer to process as alternation increases (Experiment 4). Overall, our results indicate that compared with repetition, alternation in a binary sequence is less salient in the sense of requiring more attention for successful encoding. The current study thus reveals the cognitive constraints in the representation of alternation and provides a new explanation for the overalternation bias in randomness perception. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  15. Orbital motion in pre-main sequence binaries

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, G. H. [The CHARA Array of Georgia State University, Mount Wilson Observatory, Mount Wilson, CA 91023 (United States); Prato, L. [Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001 (United States); Simon, M. [Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794 (United States); Patience, J., E-mail: schaefer@chara-array.org [Astrophysics Group, School of Physics, University of Exeter, Exeter, EX4 4QL (United Kingdom)

    2014-06-01

    We present results from our ongoing program to map the visual orbits of pre-main sequence (PMS) binaries in the Taurus star forming region using adaptive optics imaging at the Keck Observatory. We combine our results with measurements reported in the literature to analyze the orbital motion for each binary. We present preliminary orbits for DF Tau, T Tau S, ZZ Tau, and the Pleiades binary HBC 351. Seven additional binaries show curvature in their relative motion. Currently, we can place lower limits on the orbital periods for these systems; full solutions will be possible with more orbital coverage. Five other binaries show motion that is indistinguishable from linear motion. We suspect that these systems are bound and might show curvature with additional measurements in the future. The observations reported herein lay critical groundwork toward the goal of measuring precise masses for low-mass PMS stars.

  16. Design of Long Period Pseudo-Random Sequences from the Addition of m -Sequences over 𝔽 p

    OpenAIRE

    Ren Jian

    2004-01-01

    Pseudo-random sequence with good correlation property and large linear span is widely used in code division multiple access (CDMA) communication systems and cryptology for reliable and secure information transmission. In this paper, sequences with long period, large complexity, balance statistics, and low cross-correlation property are constructed from the addition of m -sequences with pairwise-prime linear spans (AMPLS). Using m -sequences as building blocks, the proposed method proved to...

  17. Memorizing binary vector sequences by a sparsely encoded network.

    Science.gov (United States)

    Baram, Y

    1994-01-01

    We present a neural network employing Hebbian storage and sparse internal coding, which is capable of memorizing and correcting sequences of binary vectors by association. A ternary version of the Kanerva memory, folded into a feedback configuration, is shown to perform the basic sequence memorization and regeneration function. The inclusion of lateral connections between the internal cells increases the network capacity considerably and facilitates the correction of individual input patterns and the detection of large errors. The introduction of higher delays in the transmission lines between the external input-output layer and the internal memory layer is shown to further improve the network's error correction capability.

  18. MAGNETIC INTERACTIONS IN PRE-MAIN-SEQUENCE BINARIES

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Fred C. [Michigan Center for Theoretical Physics Department, University of Michigan, Ann Arbor, MI 48109 (United States); Cai, Michael J.; Shu, Frank H. [Institute of Astronomy and Astrophysics, Academia Sinica, Taipei 115, Taiwan (China); Galli, Daniele [INAF-Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, I-50125 Firenze (Italy); Lizano, Susana [Centro de Radioastronomia y Astrofisica, UNAM, Apartado Postal 3-72, 58089 Morelia, Michoacan (Mexico)

    2011-12-20

    Young stars typically have strong magnetic fields, so that the magnetospheres of newly formed close binaries can interact, dissipate energy, and produce synchrotron radiation. The V773 Tau A binary system, a pair of T Tauri stars with a 51 day orbit, displays such a signature, with peak emission taking place near periastron. This paper proposes that the observed emission arises from the change in energy stored in the composite magnetic field of the system. We model the fields using the leading order (dipole) components and show that this picture is consistent with current observations. In this model, the observed radiation accounts for a fraction of the available energy of interaction between the magnetic fields from the two stars. Assuming antisymmetry, we compute the interaction energy E{sub int} as a function of the stellar radii, the stellar magnetic field strengths, the binary semimajor axis, and orbital eccentricity, all of which can be measured independently of the synchrotron radiation. The variability in time and energetics of the synchrotron radiation depend on the details of the annihilation of magnetic fields through reconnection events, which generate electric fields that accelerate charged particles, and how those charged particles, especially fast electrons, are removed from the interaction region. However, the major qualitative features are well described by the background changes in the global magnetic configuration driven by the orbital motion. The theory can be tested by observing a collection of pre-main-sequence binary systems.

  19. A Bidirectional Generalized Synchronization Theorem-Based Chaotic Pseudo-random Number Generator

    Directory of Open Access Journals (Sweden)

    Han Shuangshuang

    2013-07-01

    Full Text Available Based on a bidirectional generalized synchronization theorem for discrete chaos system, this paper introduces a new 5-dimensional bidirectional generalized chaos synchronization system (BGCSDS, whose prototype is a novel chaotic system introduced in [12]. Numerical simulation showed that two pair variables of the BGCSDS achieve generalized chaos synchronization via a transform H.A chaos-based pseudo-random number generator (CPNG was designed by the new BGCSDS. Using the FIPS-140-2 tests issued by the National Institute of Standard and Technology (NIST verified the randomness of the 1000 binary number sequences generated via the CPNG and the RC4 algorithm respectively. The results showed that all the tested sequences passed the FIPS-140-2 tests. The confidence interval analysis showed the statistical properties of the randomness of the sequences generated via the CPNG and the RC4 algorithm do not have significant differences.

  20. Next-Generation Sequencing for Binary Protein-Protein Interactions

    Directory of Open Access Journals (Sweden)

    Bernhard eSuter

    2015-12-01

    Full Text Available The yeast two-hybrid (Y2H system exploits host cell genetics in order to display binary protein-protein interactions (PPIs via defined and selectable phenotypes. Numerous improvements have been made to this method, adapting the screening principle for diverse applications, including drug discovery and the scale-up for proteome wide interaction screens in human and other organisms. Here we discuss a systematic workflow and analysis scheme for screening data generated by Y2H and related assays that includes high-throughput selection procedures, readout of comprehensive results via next-generation sequencing (NGS, and the interpretation of interaction data via quantitative statistics. The novel assays and tools will serve the broader scientific community to harness the power of NGS technology to address PPI networks in health and disease. We discuss examples of how this next-generation platform can be applied to address specific questions in diverse fields of biology and medicine.

  1. Next-Generation Sequencing for Binary Protein-Protein Interactions.

    Science.gov (United States)

    Suter, Bernhard; Zhang, Xinmin; Pesce, C Gustavo; Mendelsohn, Andrew R; Dinesh-Kumar, Savithramma P; Mao, Jian-Hua

    2015-01-01

    The yeast two-hybrid (Y2H) system exploits host cell genetics in order to display binary protein-protein interactions (PPIs) via defined and selectable phenotypes. Numerous improvements have been made to this method, adapting the screening principle for diverse applications, including drug discovery and the scale-up for proteome wide interaction screens in human and other organisms. Here we discuss a systematic workflow and analysis scheme for screening data generated by Y2H and related assays that includes high-throughput selection procedures, readout of comprehensive results via next-generation sequencing (NGS), and the interpretation of interaction data via quantitative statistics. The novel assays and tools will serve the broader scientific community to harness the power of NGS technology to address PPI networks in health and disease. We discuss examples of how this next-generation platform can be applied to address specific questions in diverse fields of biology and medicine.

  2. Cryptography, statistics and pseudo-randomness (Part 1)

    NARCIS (Netherlands)

    Brands, S.; Gill, R.D.

    1995-01-01

    In the classical approach to pseudo-random number generators, a generator is considered to perform well if its output sequences pass a battery of statistical tests that has become standard. In recent years, it has turned out that this approach is not satisfactory. Many generators have turned out to

  3. METHOD OF GENERATING COMMON CRYPTOGRAPHIC KEYS FOR LOOSLY COINCIDENT BINARY SEQUENCES

    Directory of Open Access Journals (Sweden)

    V. L. Pivovarov

    2016-01-01

    Full Text Available The method of forming a common secret binary sequence between using an open communication channel is considered. The method is not based on common unidirectional functions and results in iterative elimination of distinct bits in the initial binary sequences with a certain percentage of mismatches, intentionally made by subscribers themselves. The cryptanalysis technique of this method based on the use of the deviation of aprior distribution of probabilities of inverting bits in the original binary sequences of subscribers from uniform distribution is proposed. Part of the bits in the final secret sequence can be identified accurately enough.

  4. Autocorrelation peaks in congruential pseudorandom number generators

    Science.gov (United States)

    Neuman, F.; Merrick, R. B.

    1976-01-01

    The complete correlation structure of several congruential pseudorandom number generators (PRNG) of the same type and small cycle length was studied to deal with the problem of congruential PRNG almost repeating themselves at intervals smaller than their cycle lengths, during simulation of bandpass filtered normal random noise. Maximum period multiplicative and mixed congruential generators were studied, with inferences drawn from examination of several tractable members of a class of random number generators, and moduli from 2 to the 5th power to 2 to the 9th power. High correlation is shown to exist in mixed and multiplicative congruential random number generators and prime moduli Lehmer generators for shifts a fraction of their cycle length. The random noise sequences in question are required when simulating electrical noise, air turbulence, or time variation of wind parameters.

  5. Magnetospheric Accretion in Close Pre-main-sequence Binaries

    Science.gov (United States)

    Ardila, David R.; Jonhs-Krull, Christopher; Herczeg, Gregory J.; Mathieu, Robert D.; Quijano-Vodniza, Alberto

    2015-10-01

    The transfer of matter between a circumbinary disk and a young binary system remains poorly understood, obscuring the interpretation of accretion indicators. To explore the behavior of these indicators in multiple systems, we have performed the first systematic time-domain study of young binaries in the ultraviolet. We obtained far- and near-ultraviolet HST/COS spectra of the young spectroscopic binaries DQ Tau and UZ Tau E. Here we focus on the continuum from 2800 to 3200 Å and on the C iv doublet (λλ1548.19, 1550.77 Å) as accretion diagnostics. Each system was observed over three or four consecutive binary orbits, at phases ∼0, 0.2, 0.5, and 0.7. Those observations are complemented by ground-based U-band measurements. Contrary to model predictions, we do not detect any clear correlation between accretion luminosity and phase. Further, we do not detect any correlation between C iv flux and phase. For both stars the appearance of the C iv line is similar to that of single Classical T Tauri Stars (CTTSs), despite the lack of stable long-lived circumstellar disks. However, unlike the case in single CTTSs, the narrow and broad components of the C iv lines are uncorrelated, and we argue that the narrow component is powered by processes other than accretion, such as flares in the stellar magnetospheres and/or enhanced activity in the upper atmosphere. We find that both stars contribute equally to the narrow component C iv flux in DQ Tau, but the primary dominates the narrow component C iv emission in UZ Tau E. The C iv broad component flux is correlated with other accretion indicators, suggesting an accretion origin. However, the line is blueshifted, which is inconsistent with its origin in an infall flow close to the star. It is possible that the complicated geometry of the region, as well as turbulence in the shock region, are responsible for the blueshifted line profiles.

  6. Heterozygous genome assembly via binary classification of homologous sequence.

    Science.gov (United States)

    Bodily, Paul M; Fujimoto, M; Ortega, Cameron; Okuda, Nozomu; Price, Jared C; Clement, Mark J; Snell, Quinn

    2015-01-01

    Genome assemblers to date have predominantly targeted haploid reference reconstruction from homozygous data. When applied to diploid genome assembly, these assemblers perform poorly, owing to the violation of assumptions during both the contigging and scaffolding phases. Effective tools to overcome these problems are in growing demand. Increasing parameter stringency during contigging is an effective solution to obtaining haplotype-specific contigs; however, effective algorithms for scaffolding such contigs are lacking. We present a stand-alone scaffolding algorithm, ScaffoldScaffolder, designed specifically for scaffolding diploid genomes. The algorithm identifies homologous sequences as found in "bubble" structures in scaffold graphs. Machine learning classification is used to then classify sequences in partial bubbles as homologous or non-homologous sequences prior to reconstructing haplotype-specific scaffolds. We define four new metrics for assessing diploid scaffolding accuracy: contig sequencing depth, contig homogeneity, phase group homogeneity, and heterogeneity between phase groups. We demonstrate the viability of using bubbles to identify heterozygous homologous contigs, which we term homolotigs. We show that machine learning classification trained on these homolotig pairs can be used effectively for identifying homologous sequences elsewhere in the data with high precision (assuming error-free reads). More work is required to comparatively analyze this approach on real data with various parameters and classifiers against other diploid genome assembly methods. However, the initial results of ScaffoldScaffolder supply validity to the idea of employing machine learning in the difficult task of diploid genome assembly. Software is available at http://bioresearch.byu.edu/scaffoldscaffolder.

  7. Binary Sequences for Spread-Spectrum Multiple-Access Communication

    Science.gov (United States)

    1977-08-01

    extensively in the literature by Zierler (1959) and Golomb (1967) and others. 3.1. Introduction to m-sequences It is convenient to distinguish in our...overview of the problems and programs," Proceedings of the IEEE, vol. 65, pp. 294-307, 1977. Puente , J. 0., Schmidt, W. G., and Werth, A. M., "Multiple

  8. Curriculum Viewed as a Binary System: An Approach to the Determination of Sequence. A Project Report.

    Science.gov (United States)

    Renckly, Thomas R.; Orwig, Gary

    A description of the development and application of a hierarchical/binary model by which a curriculum may be analyzed to determine alternative instructional sequences given particular instructional objectives and limiting constraints forms the body of this report. The background of the project as part of an effort by the U.S. Navy Recruiting…

  9. High Throughput Pseudorandom Number Generator Based on Variable Argument Unified Hyperchaos

    Directory of Open Access Journals (Sweden)

    Kaiyu Wang

    2014-01-01

    Full Text Available This paper presents a new multioutput and high throughput pseudorandom number generator. The scheme is to make the homogenized Logistic chaotic sequence as unified hyperchaotic system parameter. So the unified hyperchaos can transfer in different chaotic systems and the output can be more complex with the changing of homogenized Logistic chaotic output. Through processing the unified hyperchaotic 4-way outputs, the output will be extended to 26 channels. In addition, the generated pseudorandom sequences have all passed NIST SP800-22 standard test and DIEHARD test. The system is designed in Verilog HDL and experimentally verified on a Xilinx Spartan 6 FPGA for a maximum throughput of 16.91 Gbits/s for the native chaotic output and 13.49 Gbits/s for the resulting pseudorandom number generators.

  10. Discovery and Characterization of 3000+ Main-Sequence Binaries from APOGEE Spectra

    Science.gov (United States)

    El-Badry, Kareem; Ting, Yuan-Sen; Rix, Hans-Walter; Quataert, Eliot; Weisz, Daniel R.; Cargile, Phillip; Conroy, Charlie; Hogg, David W.; Bergemann, Maria; Liu, Chao

    2018-01-01

    We develop a data-driven spectral model for identifying and characterizing spatially unresolved multiple-star systems and apply it to APOGEE DR13 spectra of main-sequence stars. Binaries and triples are identified as targets whose spectra can be significantly better fit by a superposition of two or three model spectra, drawn from the same isochrone, than any single-star model. From an initial sample of ˜20,000 main-sequence targets, we identify ˜2,500 binaries in which both the primary and secondary star contribute detectably to the spectrum, simultaneously fitting for the velocities and stellar parameters of both components. We additionally identify and fit ˜200 triple systems, as well as ˜700 velocity-variable systems in which the secondary does not contribute detectably to the spectrum. Our model simplifies the process of simultaneously fitting single- or multi-epoch spectra with composite models and does not depend on a velocity offset between the two components of a binary, making it sensitive to traditionally undetectable systems with periods of hundreds or thousands of years. In agreement with conventional expectations, almost all the spectrally-identified binaries with measured parallaxes fall above the main sequence in the color-magnitude diagram. We find excellent agreement between spectrally and dynamically inferred mass ratios for the ˜600 binaries in which a dynamical mass ratio can be measured from multi-epoch radial velocities. We obtain full orbital solutions for 64 systems, including 14 close binaries within hierarchical triples. We make available catalogs of stellar parameters, abundances, mass ratios, and orbital parameters.

  11. Nonquadratic Variation of the Blum Blum Shub Pseudorandom Number Generator

    Science.gov (United States)

    2016-09-01

    the use of random numbers. For this rea- son, cryptographers design pseudorandom number generators (PRNG) as a method of generating random numbers...fails the block frequency test, as it is clearly not random . 3.3.3 Runs Test A run is defined as a series of either 1’s or 0’s in a row. The purpose of...that would be expected of a random sequence. The NIST standard uses three common block sizes for this test, M = 8, 128, and 10, 000. The test divides

  12. Differential rotation on both components of the pre main-sequence binary system HD 155555

    OpenAIRE

    Dunstone, N. J.; Hussain, G. A. J.; Cameron, A. Collier; Marsden, S. C.; Jardine, M.; Barnes, J. R.; Vlex, J. C. Ramirez; Donati, J. -F.

    2008-01-01

    We present the first measurements of surface differential rotation on a pre-main sequence binary system. Using intensity (Stokes I) and circularly polarised (Stokes V) timeseries spectra, taken over eleven nights at the Anglo-Australian Telescope (AAT), we incorporate a solar-like differential rotation law into the surface imaging process. We find that both components of the young, 18 Myr, HD 155555 (V824 Ara, G5IV + K0IV) binary system show significant differential rotation. The equator-pole...

  13. The first magnetic maps of a pre-main sequence binary star system - HD 155555

    OpenAIRE

    Dunstone, N. J.; Hussain, G. A. J.; Cameron, A. Collier; Marsden, S. C.; Jardine, M.; Stempels, H. C.; Vlex, J. C. Ramirez; Donati, J. -F.

    2008-01-01

    We present the first maps of the surface magnetic fields of a pre-main sequence binary system. Spectropolarimetric observations of the young, 18 Myr, HD 155555 (V824 Ara, G5IV + K0IV) system were obtained at the Anglo-Australian Telescope in 2004 and 2007. Both datasets are analysed using a new binary Zeeman Doppler imaging (ZDI) code. This allows us to simultaneously model the contribution of each component to the observed circularly polarised spectra. Stellar brightness maps are also produc...

  14. Synchronized pseudorandom systems and their application to speech communication.

    Science.gov (United States)

    Zhang, Yu; Tao, Chao; Du, Gonghuan; Jiang, Jack J

    2005-01-01

    An approach to the synchronization of pseudorandom systems is proposed and applied to secure speech communication. The encoding signal produced by the pseudorandom synchronization scheme passes the random test, and shows much more complex dynamics, better random properties, and greater sensitivity to parameter mismatches than that produced by the active-passive decomposition scheme. Also, two coupled pseudorandom systems can be exactly synchronized despite their different initial states or seeds. Pseudorandom encoding and synchronization may yield great security in communication.

  15. Pseudorandomness analysis of the (extended) Lai–Massey scheme

    NARCIS (Netherlands)

    Luo, Yiyuan; Desmedt, Y.; Lai, Xuejia; Gong, Zheng

    2010-01-01

    In this paper we find that the two-round (extended) Lai–Massey scheme is not pseudorandom and three-round (extended) Lai–Massey scheme is not strong pseudorandom. Combined with previous work, we prove that three rounds are necessary and sufficient for the pseudorandomness and four rounds are

  16. YSOVAR: Six Pre-main-sequence Eclipsing Binaries in the Orion Nebula Cluster

    Science.gov (United States)

    2012-06-25

    reserved. Printed in the U.S.A. YSOVAR: SIX PRE-MAIN-SEQUENCE ECLIPSING BINARIES IN THE ORION NEBULA CLUSTER M. Morales-Calderón1,2, J. R. Stauffer1, K. G...multi-color light curves for∼2400 candidate Orion Nebula Cluster (ONC) members from our Warm Spitzer Exploration Science Program YSOVAR, we have...readable tables 1. INTRODUCTION The Orion Nebula Cluster (ONC) contains several thousand members, and since it is nearby, it provides an excellent em

  17. Pseudo-random number generator based on asymptotic deterministic randomness

    Energy Technology Data Exchange (ETDEWEB)

    Wang Kai [Department of Radio Engineering, Southeast University, Nanjing (China)], E-mail: kaiwang@seu.edu.cn; Pei Wenjiang; Xia Haishan [Department of Radio Engineering, Southeast University, Nanjing (China); Cheung Yiuming [Department of Computer Science, Hong Kong Baptist University, Hong Kong (China)

    2008-06-09

    A novel approach to generate the pseudorandom-bit sequence from the asymptotic deterministic randomness system is proposed in this Letter. We study the characteristic of multi-value correspondence of the asymptotic deterministic randomness constructed by the piecewise linear map and the noninvertible nonlinearity transform, and then give the discretized systems in the finite digitized state space. The statistic characteristics of the asymptotic deterministic randomness are investigated numerically, such as stationary probability density function and random-like behavior. Furthermore, we analyze the dynamics of the symbolic sequence. Both theoretical and experimental results show that the symbolic sequence of the asymptotic deterministic randomness possesses very good cryptographic properties, which improve the security of chaos based PRBGs and increase the resistance against entropy attacks and symbolic dynamics attacks.

  18. The population of white dwarf-main sequence binaries in the SDSS DR 12

    Science.gov (United States)

    Cojocaru, R.; Rebassa-Mansergas, A.; Torres, S.; García-Berro, E.

    2017-09-01

    We present a Monte Carlo population synthesis study of white dwarf-main sequence (WD+MS) binaries in the Galactic disc aimed at reproducing the ensemble properties of the entire population observed by the Sloan Digital Sky Survey (SDSS) Data Release 12. Our simulations take into account all known observational biases and use the most up-to-date stellar evolutionary models. This allows us to perform a sound comparison between the simulations and the observational data. We find that the properties of the simulated and observed parameter distributions agree best when assuming low values of the common envelope efficiency (0.2-0.3), a result that is in agreement with previous findings obtained by observational and population synthesis studies of close SDSS WD+MS binaries. We also show that all synthetic populations that result from adopting an initial mass ratio distribution with a positive slope are excluded by observations. Finally, we confirm that the properties of the simulated WD+MS binary populations are nearly independent of the age adopted for the thin disc, on the contribution of WD+MS binaries from the thick disc (0-17 per cent of the total population) and on the assumed fraction of the internal energy that is used to eject the envelope during the common envelope phase (0.1-0.5).

  19. Composite Binary Sequences with a Large Ensemble and Zero Correlation Zone

    Directory of Open Access Journals (Sweden)

    S. S. Yudachev

    2015-01-01

    Full Text Available The article considers a proposed class of derived signals such as composite binary sequences for application in advanced spread spectrum radio systems of various purposes, using signals based on spectrum spreading by direct sequence method. Considered composite sequences, having a representative set of lengths and unique correlation properties, compares favorably with the widely used at present large ensembles formed on a single algorithmic basis. To evaluate the properties of the composite sequences generated on the basis of two components - the Barker code and Kerdock sequences, expressions of periodic and aperiodic correlation functions are given.An algorithm for generating practical ensembles of composite sequences is presented. On the basis of the algorithm and its software implementation in C #, the samples of the sequence ensembles of various lengths were obtained and their periodic and aperiodic correlation functions and statistical characteristics were studied in detail. As an illustration, some of the most typical correlation functions are presented. The most remarkable characteristics allowing a ssessing the feasibility of using this type of sequences in the design of specific types of radio systems are considered.On the basis of the proposed program and the performed calculations the conclusions can be drawn about the possibility of using the sequences of these classes, with the aim of reducing intra-system disturbance in the projected spread spectrum CDMA.

  20. Sequence selection by dynamical symmetry breaking in an autocatalytic binary polymer model

    Science.gov (United States)

    Fellermann, Harold; Tanaka, Shinpei; Rasmussen, Steen

    2017-12-01

    Template-directed replication of nucleic acids is at the essence of all living beings and a major milestone for any origin of life scenario. We present an idealized model of prebiotic sequence replication, where binary polymers act as templates for their autocatalytic replication, thereby serving as each others reactants and products in an intertwined molecular ecology. Our model demonstrates how autocatalysis alters the qualitative and quantitative system dynamics in counterintuitive ways. Most notably, numerical simulations reveal a very strong intrinsic selection mechanism that favors the appearance of a few population structures with highly ordered and repetitive sequence patterns when starting from a pool of monomers. We demonstrate both analytically and through simulation how this "selection of the dullest" is caused by continued symmetry breaking through random fluctuations in the transient dynamics that are amplified by autocatalysis and eventually propagate to the population level. The impact of these observations on related prebiotic mathematical models is discussed.

  1. Sequence selection by dynamical symmetry breaking in an autocatalytic binary polymer model

    DEFF Research Database (Denmark)

    Fellermann, Harold; Tanaka, Shinpei; Rasmussen, Steen

    2017-01-01

    as each others reactants and products in an intertwined molecular ecology. Our model demonstrates how autocatalysis alters the qualitative and quantitative system dynamics in counterintuitive ways. Most notably, numerical simulations reveal a very strong intrinsic selection mechanism that favors......Template-directed replication of nucleic acids is at the essence of all living beings and a major milestone for any origin of life scenario. We present an idealized model of prebiotic sequence replication, where binary polymers act as templates for their autocatalytic replication, thereby serving...... the appearance of a few population structures with highly ordered and repetitive sequence patterns when starting from a pool of monomers. We demonstrate both analytically and through simulation how this "selection of the dullest" is caused by continued symmetry breaking through random fluctuations...

  2. Trifork, a New Pseudorandom Number Generator Based on Lagged Fibonacci Maps

    OpenAIRE

    Orue, A.B.; Montoya, F.; Hernández Encinas, Luis

    2010-01-01

    A new family of cryptographically secure pseudorandom number generators, is described. It is based on the combination of the sequences generated by three coupled Lagged Fibonacci generators, mutually perturbed. The mutual perturbation method consists of the bitwise XOR cross-addition of the output of each generator with the right-shifted output of the nearby generator. The proposed generator has better entropy and much longer repetition period than the conventional Lagged Fibonacci Generator....

  3. Calibration of Correlation Radiometers Using Pseudo-Random Noise Signals

    Directory of Open Access Journals (Sweden)

    Sebastián Pantoja

    2009-08-01

    Full Text Available The calibration of correlation radiometers, and particularly aperture synthesis interferometric radiometers, is a critical issue to ensure their performance. Current calibration techniques are based on the measurement of the cross-correlation of receivers’ outputs when injecting noise from a common noise source requiring a very stable distribution network. For large interferometric radiometers this centralized noise injection approach is very complex from the point of view of mass, volume and phase/amplitude equalization. Distributed noise injection techniques have been proposed as a feasible alternative, but are unable to correct for the so-called “baseline errors” associated with the particular pair of receivers forming the baseline. In this work it is proposed the use of centralized Pseudo-Random Noise (PRN signals to calibrate correlation radiometers. PRNs are sequences of symbols with a long repetition period that have a flat spectrum over a bandwidth which is determined by the symbol rate. Since their spectrum resembles that of thermal noise, they can be used to calibrate correlation radiometers. At the same time, since these sequences are deterministic, new calibration schemes can be envisaged, such as the correlation of each receiver’s output with a baseband local replica of the PRN sequence, as well as new distribution schemes of calibration signals. This work analyzes the general requirements and performance of using PRN sequences for the calibration of microwave correlation radiometers, and particularizes the study to a potential implementation in a large aperture synthesis radiometer using an optical distribution network.

  4. Calibration of correlation radiometers using pseudo-random noise signals.

    Science.gov (United States)

    Pérez, Isaac Ramos; Bosch-Lluis, Xavi; Camps, Adriano; Alvarez, Nereida Rodriguez; Hernandez, Juan Fernando Marchán; Domènech, Enric Valencia; Vernich, Carlos; de la Rosa, Sonia; Pantoja, Sebastián

    2009-01-01

    The calibration of correlation radiometers, and particularly aperture synthesis interferometric radiometers, is a critical issue to ensure their performance. Current calibration techniques are based on the measurement of the cross-correlation of receivers' outputs when injecting noise from a common noise source requiring a very stable distribution network. For large interferometric radiometers this centralized noise injection approach is very complex from the point of view of mass, volume and phase/amplitude equalization. Distributed noise injection techniques have been proposed as a feasible alternative, but are unable to correct for the so-called "baseline errors" associated with the particular pair of receivers forming the baseline. In this work it is proposed the use of centralized Pseudo-Random Noise (PRN) signals to calibrate correlation radiometers. PRNs are sequences of symbols with a long repetition period that have a flat spectrum over a bandwidth which is determined by the symbol rate. Since their spectrum resembles that of thermal noise, they can be used to calibrate correlation radiometers. At the same time, since these sequences are deterministic, new calibration schemes can be envisaged, such as the correlation of each receiver's output with a baseband local replica of the PRN sequence, as well as new distribution schemes of calibration signals. This work analyzes the general requirements and performance of using PRN sequences for the calibration of microwave correlation radiometers, and particularizes the study to a potential implementation in a large aperture synthesis radiometer using an optical distribution network.

  5. A new system identification approach to identify genetic variants in sequencing studies for a binary phenotype.

    Science.gov (United States)

    Kang, Guolian; Bi, Wenjian; Zhao, Yanlong; Zhang, Ji-Feng; Yang, Jun J; Xu, Heng; Loh, Mignon L; Hunger, Stephen P; Relling, Mary V; Pounds, Stanley; Cheng, Cheng

    2014-01-01

    We propose in this paper a set-valued (SV) system model, which is a generalized form of logistic (LG) and Probit (Probit) regression, to be considered as a method for discovering genetic variants, especially rare genetic variants in next-generation sequencing studies, for a binary phenotype. We propose a new SV system identification method to estimate all underlying key system parameters for the Probit model and compare it with the LG model in the setting of genetic association studies. Across an extensive series of simulation studies, the Probit method maintained type I error control and had similar or greater power than the LG method, which is robust to different distributions of noise: logistic, normal, or t distributions. Additionally, the Probit association parameter estimate was 2.7-46.8-fold less variable than the LG log-odds ratio association parameter estimate. Less variability in the association parameter estimate translates to greater power and robustness across the spectrum of minor allele frequencies (MAFs), and these advantages are the most pronounced for rare variants. For instance, in a simulation that generated data from an additive logistic model with an odds ratio of 7.4 for a rare single nucleotide polymorphism with a MAF of 0.005 and a sample size of 2,300, the Probit method had 60% power whereas the LG method had 25% power at the α = 10(-6) level. Consistent with these simulation results, the set of variants identified by the LG method was a subset of those identified by the Probit method in two example analyses. Thus, we suggest the Probit method may be a competitive alternative to the LG method in genetic association studies such as candidate gene, genome-wide, or next-generation sequencing studies for a binary phenotype.

  6. A New System Identification Approach to Identifying Genetic Variants in Sequencing Studies for A Binary Phenotype

    Science.gov (United States)

    Kang, Guolian; Bi, Wenjian; Zhao, Yanlong; Zhang, Ji-Feng; Yang, Jun J.; Xu, Heng; Loh, Mignon L.; Hunger, Stephen P.; Relling, Mary V.; Pounds, Stanley; Cheng, Cheng

    2014-01-01

    We propose in this paper a set-valued (SV) system model, which is a generalized form of Logistic (LG) and Probit (Probit) regression, to be considered as a method for discovering genetic variants, especially rare genetic variants in next generation sequencing studies, for a binary phenotype. We propose a new set-valued system identification method to estimate all the underlying key system parameters for the Probit model and compare it with the LG model in the setting of genetic association studies. Across an extensive series of simulation studies, the Probit method maintained Type I error control and had similar or greater power than the LG method which is robust to different distributions of noise: logistic, normal or t distributions. Additionally, the Probit association parameter estimate was 2.7–46.8 fold less variable than the LG log-odds ratio association parameter estimate. Less variability in the association parameter estimate translates to greater power and robustness across the spectrum of minor allele frequencies (MAFs), and these advantages are the most pronounced for rare variants. For instance, in a simulation that generated data from an additive logistic model with odds ratio of 7.4 for a rare single nucleotide polymorphism with a MAF of 0.005 and a sample size of 2300, the Probit method had 60% power whereas the LG method had 25% power at the α=10−6 level. Consistent with these simulation results, the set of variants identified by the LG method was a subset of those identified by the Probit method in two example analyses. Thus, we suggest the Probit method may be a competitive alternative to the LG method in genetic association studies such as candidate gene, genome-wide, or next generation sequencing studies for a binary phenotype. PMID:25096228

  7. Research of the method of pseudo-random number generation based on asynchronous cellular automata with several active cells

    Directory of Open Access Journals (Sweden)

    Bilan Stepan

    2017-01-01

    Full Text Available To date, there are many tasks that are aimed at studying the dynamic changes in physical processes. These tasks do not give advance known result. The solution of such problems is based on the construction of a dynamic model of the object. Successful structural and functional implementation of the object model can give a positive result in time. This approach uses the task of constructing artificial biological objects. To solve such problems, pseudo-random number generators are used, which also find wide application for information protection tasks. Such generators should have good statistical properties and give a long repetition period of the generated pseudo-random bit sequence. This work is aimed at improving these characteristics. The paper considers the method of forming pseudo-random sequences of numbers on the basis of aperiodic cellular automata with two active cells. A pseudo-random number generator is proposed that generates three bit sequences. The first two bit sequences are formed by the corresponding two active cells in the cellular automaton. The third bit sequence is the result of executing the XOR function over the bits of the first two sequences and it has better characteristics compared to them. The use of cellular automata with two active cells allowed to improve the statistical properties of the formed bit sequence, as well as its repetition period. This is proved by using graphical tests for generators built based on cellular automata using the neighborhoods of von Neumann and Moore. The tests showed high efficiency of the generator based on an asynchronous cellular automaton with the neighborhood of Moore. The proposed pseudo-random number generators have good statistical properties, which makes it possible to use them in information security systems, as well as for simulation tasks of various dynamic processes.

  8. The orbits of subdwarf-B + main-sequence binaries. III. The period-eccentricity distribution

    Science.gov (United States)

    Vos, J.; Østensen, R. H.; Vučković, M.; Van Winckel, H.

    2017-09-01

    Context. The predicted orbital-period distribution of the subdwarf-B (sdB) population is bi-modal with peaks at short (500 days) periods. Observationally, many short-period sdB systems are known, but only few wide sdB binaries have been studied in detail. Based on a long-term monitoring programme the wide sdB sample has been increased, discovering an unexpected positive correlation between the eccentricity and orbital period. Aims: In this article we present the orbital solution and spectral analysis of four new systems, BD-7°5977, EC 11031-1348, TYC 2084-448-1 and TYC 3871-835-1, and update the orbital solution of PG 1104+243. Using the whole sample of wide sdB binaries, we aim to find possible correlations between orbital and spectral properties. The ultimate goal is to improve theoretical models of Roche-lobe overflow. Methods: High-resolution spectroscopic time series were obtained to determine the RVs of both the sdB and main sequence (MS) components. Literature photometry was used to construct the spectral-energy distributions, which were fitted with atmosphere models to determine the surface gravities and temperatures of both components in all systems. Spectral parameters of the cool companion were verified using the GSSP code. Furthermore the amount of accreted mass was estimated. Results: Orbital parameters matching the earlier observed period-eccentricity relation were found for three systems, while TYC 2084-448-1 is found to have a lower eccentricity than expected from the period-eccentricity trend indicated by the other systems. Based on new observations, the orbit of PG 1104+243 has a small but significant eccentricity of 0.04 ± 0.02, matching that of the other systems with similar periods. Furthermore, a positive correlation between accreted mass and orbital period was found, as well as a possible relation between the initial mass-ratio and the final period-eccentricity. Conclusions: The wide sdB-binary sample shows interesting possible correlations

  9. FREQUENCY ANALYSIS OF RLE-BLOCKS REPETITIONS IN THE SERIES OF BINARY CODES WITH OPTIMAL MINIMAX CRITERION OF AUTOCORRELATION FUNCTION

    Directory of Open Access Journals (Sweden)

    A. A. Kovylin

    2013-01-01

    Full Text Available The article describes the problem of searching for binary pseudo-random sequences with quasi-ideal autocorrelation function, which are to be used in contemporary communication systems, including mobile and wireless data transfer interfaces. In the synthesis of binary sequences sets, the target set is manning them based on the minimax criterion by which a sequence is considered to be optimal according to the intended application. In the course of the research the optimal sequences with order of up to 52 were obtained; the analysis of Run Length Encoding was carried out. The analysis showed regularities in the distribution of series number of different lengths in the codes that are optimal on the chosen criteria, which would make it possible to optimize the searching process for such codes in the future.

  10. Least squares deconvolution for leak detection with a pseudo random binary sequence excitation

    Science.gov (United States)

    Nguyen, Si Tran Nguyen; Gong, Jinzhe; Lambert, Martin F.; Zecchin, Aaron C.; Simpson, Angus R.

    2018-01-01

    Leak detection and localisation is critical for water distribution system pipelines. This paper examines the use of the time-domain impulse response function (IRF) for leak detection and localisation in a pressurised water pipeline with a pseudo random binary sequence (PRBS) signal excitation. Compared to the conventional step wave generated using a single fast operation of a valve closure, a PRBS signal offers advantageous correlation properties, in that the signal has very low autocorrelation for lags different from zero and low cross correlation with other signals including noise and other interference. These properties result in a significant improvement in the IRF signal to noise ratio (SNR), leading to more accurate leak localisation. In this paper, the estimation of the system IRF is formulated as an optimisation problem in which the l2 norm of the IRF is minimised to suppress the impact of noise and interference sources. Both numerical and experimental data are used to verify the proposed technique. The resultant estimated IRF provides not only accurate leak location estimation, but also good sensitivity to small leak sizes due to the improved SNR.

  11. The amino acid alphabet and the architecture of the protein sequence-structure map. I. Binary alphabets.

    Science.gov (United States)

    Ferrada, Evandro

    2014-12-01

    The correspondence between protein sequences and structures, or sequence-structure map, relates to fundamental aspects of structural, evolutionary and synthetic biology. The specifics of the mapping, such as the fraction of accessible sequences and structures, or the sequences' ability to fold fast, are dictated by the type of interactions between the monomers that compose the sequences. The set of possible interactions between monomers is encapsulated by the potential energy function. In this study, I explore the impact of the relative forces of the potential on the architecture of the sequence-structure map. My observations rely on simple exact models of proteins and random samples of the space of potential energy functions of binary alphabets. I adopt a graph perspective and study the distribution of viable sequences and the structures they produce, as networks of sequences connected by point mutations. I observe that the relative proportion of attractive, neutral and repulsive forces defines types of potentials, that induce sequence-structure maps of vastly different architectures. I characterize the properties underlying these differences and relate them to the structure of the potential. Among these properties are the expected number and relative distribution of sequences associated to specific structures and the diversity of structures as a function of sequence divergence. I study the types of binary potentials observed in natural amino acids and show that there is a strong bias towards only some types of potentials, a bias that seems to characterize the folding code of natural proteins. I discuss implications of these observations for the architecture of the sequence-structure map of natural proteins, the construction of random libraries of peptides, and the early evolution of the natural amino acid alphabet.

  12. Cross-utilizing hyperchaotic and DNA sequences for image encryption

    Science.gov (United States)

    Zhan, Kun; Wei, Dong; Shi, Jinhui; Yu, Jun

    2017-01-01

    The hyperchaotic sequence and the DNA sequence are utilized jointly for image encryption. A four-dimensional hyperchaotic system is used to generate a pseudorandom sequence. The main idea is to apply the hyperchaotic sequence to almost all steps of the encryption. All intensity values of an input image are converted to a serial binary digit stream, and the bitstream is scrambled globally by the hyperchaotic sequence. DNA algebraic operation and complementation are performed between the hyperchaotic sequence and the DNA sequence to obtain a robust encryption performance. The experiment results demonstrate that the encryption algorithm achieves the performance of the state-of-the-art methods in term of quality, security, and robustness against noise and cropping attack.

  13. YSOVAR: SIX PRE-MAIN-SEQUENCE ECLIPSING BINARIES IN THE ORION NEBULA CLUSTER

    Energy Technology Data Exchange (ETDEWEB)

    Morales-Calderon, M.; Stauffer, J. R.; Rebull, L. M. [Spitzer Science Center, California Institute of Technology, 1200 E California Blvd., Pasadena, CA 91125 (United States); Stassun, K. G. [Physics and Astronomy Department, Vanderbilt University, 1807 Station B, Nashville, TN 37235 (United States); Vrba, F. J. [U. S. Naval Observatory, Flagstaff Station, 10391 W. Naval Observatory Road, Flagstaff, AZ 86001-8521 (United States); Prato, L. [Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001 (United States); Hillenbrand, L. A.; Carpenter, J. M. [Astronomy Department, California Institute of Technology, 1200 E California Blvd., Pasadena, CA 91125 (United States); Terebey, S.; Angione, J. [Department of Physics and Astronomy, California State University at Los Angeles, Los Angeles, CA 90032 (United States); Covey, K. R. [Department of Astronomy, Cornell University, 226 Space Sciences Building, Ithaca, NY 14853 (United States); Terndrup, D. M. [Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Gutermuth, R. [Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States); Song, I. [Physics and Astronomy Department, University of Georgia, Athens, GA 30602-2451 (United States); Plavchan, P. [NASA Exoplanet Science Institute, California Institute of Technology, Pasadena, CA 91125 (United States); Marchis, F. [SETI Institute, Carl Sagan Center, 189 N San Bernado Av, Mountain View, CA 94043 (United States); Garcia, E. V. [Department of Physics, Fisk University, 1000 17th Ave. N, Nashville, TN 37208 (United States); Margheim, S. [Gemini Observatory, Southern Operations Center, Casilla 603, La Serena (Chile); Luhman, K. L. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); Irwin, J. M., E-mail: mariamc@cab.inta-csic.es [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States)

    2012-07-10

    Eclipsing binaries (EBs) provide critical laboratories for empirically testing predictions of theoretical models of stellar structure and evolution. Pre-main-sequence (PMS) EBs are particularly valuable, both due to their rarity and the highly dynamic nature of PMS evolution, such that a dense grid of PMS EBs is required to properly calibrate theoretical PMS models. Analyzing multi-epoch, multi-color light curves for {approx}2400 candidate Orion Nebula Cluster (ONC) members from our Warm Spitzer Exploration Science Program YSOVAR, we have identified 12 stars whose light curves show eclipse features. Four of these 12 EBs are previously known. Supplementing our light curves with follow-up optical and near-infrared spectroscopy, we establish two of the candidates as likely field EBs lying behind the ONC. We confirm the remaining six candidate systems, however, as newly identified ONC PMS EBs. These systems increase the number of known PMS EBs by over 50% and include the highest mass ({theta}{sup 1} Ori E, for which we provide a complete set of well-determined parameters including component masses of 2.807 and 2.797 M{sub Sun }) and longest-period (ISOY J053505.71-052354.1, P {approx} 20 days) PMS EBs currently known. In two cases ({theta}{sup 1} Ori E and ISOY J053526.88-044730.7), enough photometric and spectroscopic data exist to attempt an orbit solution and derive the system parameters. For the remaining systems, we combine our data with literature information to provide a preliminary characterization sufficient to guide follow-up investigations of these rare, benchmark systems.

  14. The age-metallicity relation in the solar neighbourhood from a pilot sample of white dwarf-main sequence binaries

    Science.gov (United States)

    Rebassa-Mansergas, A.; Anguiano, B.; García-Berro, E.; Freeman, K. C.; Cojocaru, R.; Manser, C. J.; Pala, A. F.; Gänsicke, B. T.; Liu, X.-W.

    2016-12-01

    The age-metallicity relation (AMR) is a fundamental observational constraint for understanding how the Galactic disc formed and evolved chemically in time. However, there is not yet an agreement on the observational properties of the AMR for the solar neighbourhood, primarily due to the difficulty in obtaining accurate stellar ages for individual field stars. We have started an observational campaign for providing the much needed observational input by using wide white-dwarf-main-sequence (WDMS) binaries. White dwarfs are `natural' clocks and can be used to derive accurate ages. Metallicities can be obtained from the main-sequence companions. Since the progenitors of white dwarfs and the main-sequence stars were born at the same time, WDMS binaries provide a unique opportunity to observationally constrain in a robust way the properties of the AMR. In this work we present the AMR derived from analysing a pilot sample of 23 WDMS binaries and provide clear observational evidence for the lack of correlation between age and metallicity at young and intermediate ages (0-7 Gyr).

  15. Binary star influence on post-main-sequence multi-planet stability

    Science.gov (United States)

    Veras, Dimitri; Georgakarakos, Nikolaos; Dobbs-Dixon, Ian; Gänsicke, Boris T.

    2017-02-01

    Nearly every star known to host planets will become a white dwarf, and nearly 100 planet-hosts are now known to be accompanied by binary stellar companions. Here, we determine how a binary companion triggers instability in otherwise unconditionally stable single-star two-planet systems during the giant branch and white dwarf phases of the planet host. We perform about 700 full-lifetime (14 Gyr) simulations with A0 and F0 primary stars and secondary K2 companions, and identify the critical binary distance within which instability is triggered at any point during stellar evolution. We estimate this distance to be about seven times the outer planet separation for circular binaries. Our results help characterize the fates of planetary systems, and in particular which ones might yield architectures which are conducive to generating observable metal pollution in white dwarf atmospheres.

  16. Study of a New Chaotic Dynamical System and Its Usage in a Novel Pseudorandom Bit Generator

    Directory of Open Access Journals (Sweden)

    Ana-Cristina Dăscălescu

    2013-01-01

    Full Text Available A new chaotic discrete dynamical system, built on trigonometric functions, is proposed. With intent to use this system within cryptographic applications, we proved with the aid of specific tools from chaos theory (e.g., Lyapunov exponent, attractor’s fractal dimension, and Kolmogorov-Smirnov test and statistics (e.g., NIST suite of tests that the newly proposed dynamical system has a chaotic behavior, for a large parameter’s value space, and very good statistical properties, respectively. Further, the proposed chaotic dynamical system is used, in conjunction with a binary operation, in the designing of a new pseudorandom bit generator (PRBG model. The PRBG is subjected, by turns, to an assessment of statistical properties. Theoretical and practical arguments, rounded by good statistical results, confirm viability of the proposed chaotic dynamical system and newly designed PRBG, recommending them for usage within cryptographic applications.

  17. ADIABATIC MASS LOSS IN BINARY STARS. II. FROM ZERO-AGE MAIN SEQUENCE TO THE BASE OF THE GIANT BRANCH

    Energy Technology Data Exchange (ETDEWEB)

    Ge, Hongwei; Chen, Xuefei; Han, Zhanwen [Yunnan Observatories, The Chinese Academy of Sciences, Kunming 650011 (China); Webbink, Ronald F., E-mail: hongwei.ge@gmail.com, E-mail: rwebbink@illinois.edu [Department of Astronomy, University of Illinois, 1002 W. Green St., Urbana, IL 61801 (United States)

    2015-10-10

    In the limit of extremely rapid mass transfer, the response of a donor star in an interacting binary becomes asymptotically one of adiabatic expansion. We survey here adiabatic mass loss from Population I stars (Z = 0.02) of mass 0.10 M{sub ⊙}–100 M{sub ⊙} from the zero-age main sequence to the base of the giant branch, or to central hydrogen exhaustion for lower main sequence stars. The logarithmic derivatives of radius with respect to mass along adiabatic mass-loss sequences translate into critical mass ratios for runaway (dynamical timescale) mass transfer, evaluated here under the assumption of conservative mass transfer. For intermediate- and high-mass stars, dynamical mass transfer is preceded by an extended phase of thermal timescale mass transfer as the star is stripped of most of its envelope mass. The critical mass ratio q{sub ad} (throughout this paper, we follow the convention of defining the binary mass ratio as q ≡ M{sub donor}/M{sub accretor}) above which this delayed dynamical instability occurs increases with advancing evolutionary age of the donor star, by ever-increasing factors for more massive donors. Most intermediate- or high-mass binaries with nondegenerate accretors probably evolve into contact before manifesting this instability. As they approach the base of the giant branch, however, and begin developing a convective envelope, q{sub ad} plummets dramatically among intermediate-mass stars, to values of order unity, and a prompt dynamical instability occurs. Among low-mass stars, the prompt instability prevails throughout main sequence evolution, with q{sub ad} declining with decreasing mass, and asymptotically approaching q{sub ad} = 2/3, appropriate to a classical isentropic n = 3/2 polytrope. Our calculated q{sub ad} values agree well with the behavior of time-dependent models by Chen and Han of intermediate-mass stars initiating mass transfer in the Hertzsprung gap. Application of our results to cataclysmic variables, as systems

  18. Influence of pseudorandom bit format on the direct modulation ...

    Indian Academy of Sciences (India)

    The differences in the relative contributions of the intrinsic noise of the laser and the pseudorandom bit-pattern effect to the modulation characteristics are presented. We introduce an approximate estimation to the transient properties that control the digital modulation performance, namely, the modulation bit rate and the ...

  19. Efficient Quantum Pseudorandomness with Nearly Time-Independent Hamiltonian Dynamics

    Directory of Open Access Journals (Sweden)

    Yoshifumi Nakata

    2017-04-01

    Full Text Available Quantum randomness is an essential key to understanding the dynamics of complex many-body systems and also a powerful tool for quantum engineering. However, exact realizations of quantum randomness take an extremely long time and are infeasible in many-body systems, leading to the notion of quantum pseudorandomness, also known as unitary designs. Here, to explore microscopic dynamics of generating quantum pseudorandomness in many-body systems, we provide new efficient constructions of unitary designs and propose a design Hamiltonian, a random Hamiltonian of which dynamics always forms a unitary design after a threshold time. The new constructions are based on the alternate applications of random potentials in the generalized position and momentum spaces, and we provide explicit quantum circuits generating quantum pseudorandomness significantly more efficient than previous ones. We then provide a design Hamiltonian in disordered systems with periodically changing spin-glass-type interactions. The design Hamiltonian generates quantum pseudorandomness in a constant time even in the system composed of a large number of spins. We also point out the close relationship between the design Hamiltonian and quantum chaos.

  20. The autocorrelation structure of Tausworthe pseudorandom number generators

    Science.gov (United States)

    Neuman, F.; Martin, C. F.

    1976-01-01

    An algorithm for determining the autocorrelation structure of a new sequence generated from an original sequence by proper decimation (a shift with each q-th term of the original sequence used) is presented, once autocorrelations for any repeating number sequence are known. The autocorrelation structure of the Tausworthe random number generator (RNG), based on proper decimation by q, is accepted as a RNG structure in which a proper decimation generates a long interval over which autocorrelations are small for all shifts. It is shown that if L bits of an N-bit Tausworthe RNG are L-bit binary numbers, L + 1 levels of correlation will exist, and L levels of correlation will each occur twice per RNG cycle length.

  1. A Wide Angle Survey of Young Stellar Associations for Hot Jupiters and Pre-Main Sequence Binaries

    Science.gov (United States)

    Oelkers, Ryan J.; Macri, Lucas M.; Marshall, Jennifer L.; Depoy, Darren L.; Garcia Lambas, Diego

    2016-01-01

    The past two decades have seen a significant advancement in the detection, classification and understanding of exoplanets and binary star systems. The vast majority of these systems consist of objects on the main sequence or the giant branch, leading to a dearth of knowledge of properties at early times (migration models. The deficiency in the number of well characterized systems is driven by the inherent and aperiodic variability found in pre-main sequence objects which can mask and mimic eclipse signals. Nevertheless a dramatic increase in the total number of systems at early times is required to alleviate the conflict between theory and observation. I have recently completed a photometric survey of 3 nearby (migration timescale.

  2. Coding Local and Global Binary Visual Features Extracted From Video Sequences.

    Science.gov (United States)

    Baroffio, Luca; Canclini, Antonio; Cesana, Matteo; Redondi, Alessandro; Tagliasacchi, Marco; Tubaro, Stefano

    2015-11-01

    Binary local features represent an effective alternative to real-valued descriptors, leading to comparable results for many visual analysis tasks while being characterized by significantly lower computational complexity and memory requirements. When dealing with large collections, a more compact representation based on global features is often preferred, which can be obtained from local features by means of, e.g., the bag-of-visual word model. Several applications, including, for example, visual sensor networks and mobile augmented reality, require visual features to be transmitted over a bandwidth-limited network, thus calling for coding techniques that aim at reducing the required bit budget while attaining a target level of efficiency. In this paper, we investigate a coding scheme tailored to both local and global binary features, which aims at exploiting both spatial and temporal redundancy by means of intra- and inter-frame coding. In this respect, the proposed coding scheme can conveniently be adopted to support the analyze-then-compress (ATC) paradigm. That is, visual features are extracted from the acquired content, encoded at remote nodes, and finally transmitted to a central controller that performs the visual analysis. This is in contrast with the traditional approach, in which visual content is acquired at a node, compressed and then sent to a central unit for further processing, according to the compress-then-analyze (CTA) paradigm. In this paper, we experimentally compare the ATC and the CTA by means of rate-efficiency curves in the context of two different visual analysis tasks: 1) homography estimation and 2) content-based retrieval. Our results show that the novel ATC paradigm based on the proposed coding primitives can be competitive with the CTA, especially in bandwidth limited scenarios.

  3. Chaos-based Pseudo-random Number Generation

    KAUST Repository

    Barakat, Mohamed L.

    2014-04-10

    Various methods and systems related to chaos-based pseudo-random number generation are presented. In one example, among others, a system includes a pseudo-random number generator (PRNG) to generate a series of digital outputs and a nonlinear post processing circuit to perform an exclusive OR (XOR) operation on a first portion of a current digital output of the PRNG and a permutated version of a corresponding first portion of a previous post processed output to generate a corresponding first portion of a current post processed output. In another example, a method includes receiving at least a first portion of a current output from a PRNG and performing an XOR operation on the first portion of the current PRNG output with a permutated version of a corresponding first portion of a previous post processed output to generate a corresponding first portion of a current post processed output.

  4. Facial Expression Recognition from Video Sequences Based on Spatial-Temporal Motion Local Binary Pattern and Gabor Multiorientation Fusion Histogram

    Directory of Open Access Journals (Sweden)

    Lei Zhao

    2017-01-01

    Full Text Available This paper proposes novel framework for facial expressions analysis using dynamic and static information in video sequences. First, based on incremental formulation, discriminative deformable face alignment method is adapted to locate facial points to correct in-plane head rotation and break up facial region from background. Then, spatial-temporal motion local binary pattern (LBP feature is extracted and integrated with Gabor multiorientation fusion histogram to give descriptors, which reflect static and dynamic texture information of facial expressions. Finally, a one-versus-one strategy based multiclass support vector machine (SVM classifier is applied to classify facial expressions. Experiments on Cohn-Kanade (CK + facial expression dataset illustrate that integrated framework outperforms methods using single descriptors. Compared with other state-of-the-art methods on CK+, MMI, and Oulu-CASIA VIS datasets, our proposed framework performs better.

  5. A Multi-Threaded Cryptographic Pseudorandom Number Generator Test Suite

    Science.gov (United States)

    2016-09-01

    Cloud GSL GNU scientific library KSTEST Kolmogorov-Smirnov test NIST National Institute for Standards and Technology OpenMP Open Multi-Processing OTP...one-time pad POSIX Portable Operating System Interface PRNG pseudorandom number generator RA resolve ambiguity RNG random number generator SSH secure...chats of Cryptocat due to a programming flaw [1]. A bug in the BigInt library caused the random number generator to have a slight bias when generating

  6. Infrared Light Curves of Parenago 1802: A Low Mass, Pre-Main Sequence, Eclipsing Binary

    Science.gov (United States)

    Gomez Maqueo Chew, Yilen; Stassun, K. G.; Prsa, A.; Cargile, P.; Mathieu, R.

    2007-12-01

    We present J and K near-infrared light curves of eclipsing binary Par 1802 obtained with the 1.3m SMARTS telescope at CTIO. We combine these observations with previously published light curves and radial velocities. The light curves in the out-of-eclipse phases are searched for periodicities which may be due to spots on the surface of one or both of the components. The modeling of the light curves and radial velocity curves is done using the Wilson- Devinney based code, PHOEBE. A careful assessment of the solution is also presented using a Monte-Carlo sampling of the parameter hyperspace providing heuristically error estimates. The compound analysis of the photometric and spectroscopic data allows for precise measurement of the system's physical parameters, complementing previous results. The components of this system have masses below half a solar mass making them one of the few dynamically measured in this mass regime. Moreover, while the masses of the two stars are equal, they seem to have different temperatures and radii. This surprising result provides key information for the calibration of star formation and evolution models.

  7. On pseudorandom generators in NC0

    DEFF Research Database (Denmark)

    Cryan, Mary; Miltersen, Peter Bro

    2001-01-01

    In this paper we consider the question of whether NC 0 circuits can generate pseudorandom distributions. While we leave the general question unanswered, we show – • Generators computed by NC 0 circuits where each output bit depends on at most 3 input bits (i.e, DNC 3 0 circuits) and with stretch....... – • There is an NC 4 0 generator with a super-linear stretch that passes the linear dependency test as well as k-wise independence tests, for any constant k....

  8. A Family of Controllable Cellular Automata for Pseudorandom Number Generation

    OpenAIRE

    Guan, SU; Zhang, S.

    2002-01-01

    In this paper, we present a family of novel Pseudorandom Number Generators (PRNGs) based on Controllable Cellular Automata (CCA) ─ CCA0, CCA1, CCA2 (NCA), CCA3 (BCA), CCA4 (asymmetric NCA), CCA5, CCA6 and CCA7 PRNGs. The ENT and DIEHARD test suites are used to evaluate the randomness of these CCA PRNGs. The results show that their randomness is better than that of conventional CA and PCA PRNGs while they do not lose the structure simplicity of 1-d CA. Moreover, their randomness can be compara...

  9. Algorithm for generation pseudo-random series with arbitrarily assigned distribution law

    Directory of Open Access Journals (Sweden)

    В.С. Єременко

    2005-04-01

    Full Text Available  Method for generation pseudo-random series with arbitrarily assigned distribution law has been proposed. The praxis of using proposed method for generation pseudo-random series with anti-modal and approximate to Gaussian distribution law has been investigated.

  10. PRIMITIVE MATRICES AND GENERATORS OF PSEUDO RANDOM SEQUENCES OF GALOIS

    Directory of Open Access Journals (Sweden)

    A. Beletsky

    2014-04-01

    Full Text Available In theory and practice of information cryptographic protection one of the key problems is the forming a binary pseudo-random sequences (PRS with a maximum length with acceptable statistical characteristics. PRS generators are usually implemented by linear shift register (LSR of maximum period with linear feedback [1]. In this paper we extend the concept of LSR, assuming that each of its rank (memory cell can be in one of the following condition. Let’s call such registers “generalized linear shift register.” The research goal is to develop algorithms for constructing Galois and Fibonacci generalized matrix of n-order over the field , which uniquely determined both the structure of corresponding generalized of n-order LSR maximal period, and formed on their basis Galois PRS generators of maximum length. Thus the article presents the questions of formation the primitive generalized Fibonacci and Galois arbitrary order matrix over the prime field . The synthesis of matrices is based on the use of irreducible polynomials of degree and primitive elements of the extended field generated by polynomial. The constructing methods of Galois and Fibonacci conjugated primitive matrices are suggested. The using possibilities of such matrices in solving the problem of constructing generalized generators of Galois pseudo-random sequences are discussed.

  11. Quantum-key-distribution protocol with pseudorandom bases

    Science.gov (United States)

    Trushechkin, A. S.; Tregubov, P. A.; Kiktenko, E. O.; Kurochkin, Y. V.; Fedorov, A. K.

    2018-01-01

    Quantum key distribution (QKD) offers a way for establishing information-theoretical secure communications. An important part of QKD technology is a high-quality random number generator for the quantum-state preparation and for post-processing procedures. In this work, we consider a class of prepare-and-measure QKD protocols, utilizing additional pseudorandomness in the preparation of quantum states. We study one of such protocols and analyze its security against the intercept-resend attack. We demonstrate that, for single-photon sources, the considered protocol gives better secret key rates than the BB84 and the asymmetric BB84 protocols. However, the protocol strongly requires single-photon sources.

  12. Pseudo-random Spray Release to Measure World-wide Transfer Functions of Cloud Albedo Control.

    Science.gov (United States)

    Salter, Stephen

    2010-05-01

    Institute for Energy Systems, School of Engineering, University of Edinburgh. S.Salter@ed.ac.uk Previous climate models of Latham's proposal to reverse global warming by using sub-micron sea spray to increase cloud albedo have used a variety of spray patterns. Kettles forced CCN concentration to be 375/cm3 everywhere. Rasch et al used the 20% and 70% most susceptible regions. Bala and Caldeira used an even spread. Jones et al. concentrated spray in the 3.3% oceans with the highest susceptibility All used the same rate through the year. We want to choose a scheme for a climate-modelling experiment designed to identify simultaneously the effects of cloud albedo control at various seasons of the year from spray at all regions of the world on climates of all other regions the world. In particular we want to know seasons and spray places which might have an undesirable effect on precipitation. The spray systems in various regions of a numerical climate model will be modulated on an off with different but known pseudo-random sequences and a selection of seasons. The mean value of the resulting weather records of the parameters of interest, mainly temperature and water run-off, at each region will be subtracted from each value of the record so as to give just the alternating component with an average value of zero. This will be correlated with each of the chosen pseudo-random sequences to give the magnitude and polarity of the effect of a treatment at each input area and selected seasons of the year with the resulting effects on all regions. By doing a time-shifted correlation we can account for phase-shift and time delay. The signal-to-noise ratio should improve with the square root of the analysis time and so we may be able to measure the transfer function with quite a small stimulus. The results of a Mathcad simulation of the process with statistical distributions approximating to natural variations temperature and precipitation show that a single run of a climate

  13. VizieR Online Data Catalog: SDSS WD main-sequence binaries. XII. (Nebot Gomez-Moran+, 2011)

    Science.gov (United States)

    Nebot Gomez-Moran, A.; Gaensicke, B. T.; Schreiber, M. R.; Rebassa-Mansergas, A.; Schwope, A. D.; Southworth, J.; Aungwerojwit, A.; Bothe, M.; Davis, P. J.; Kolb, U.; Mueller, M.; Papadaki, C.; Pyrzas, S.; Rabitz, A.; Rodriguez-Gil, P.; Schmidtobreick, L.; Schwarz, R.; Tappert, C.; Toloza, O.; Vogel, J.; Zorotovic, M.

    2013-02-01

    Table3.dat lists only radial velocities used for the identification of the binary as a close or wide binary candidate. Table4.dat contains the total number of spectra used for identification of the binary, the number of spectra from own spectroscopic follow-up observations and the statistical significance of the radial velocity variations. Table6.dat list radial velocities limited to the spectra used for the determination of the orbital period. Stellar parameters have been taken from Rebassa-Mansergas et al (2010, Cat., J/MNRAS/402/620, 2011, in prep.). Some radial velocities have already been published in Schreiber et al. (2008A&A...484..441S, 2010A&A...513L...7S) (5 data files).

  14. Generalized Hardware Post‐processing Technique for Chaos‐Based Pseudorandom Number Generators

    National Research Council Canada - National Science Library

    Barakat, Mohamed L; Mansingka, Abhinav S; Radwan, Ahmed G; Salama, Khaled N

    2013-01-01

    ...‐based operation with rotation and feedback. The technique allows full utilization of the chaotic output as pseudorandom number generators and improves throughput without a significant area penalty...

  15. Pseudo-random dynamic address configuration (PRDAC) algorithm for mobile ad hoc networks

    Science.gov (United States)

    Wu, Shaochuan; Tan, Xuezhi

    2007-11-01

    By analyzing all kinds of address configuration algorithms, this paper provides a new pseudo-random dynamic address configuration (PRDAC) algorithm for mobile ad hoc networks. Based on PRDAC, the first node that initials this network randomly chooses a nonlinear shift register that can generates an m-sequence. When another node joins this network, the initial node will act as an IP address configuration sever to compute an IP address according to this nonlinear shift register, and then allocates this address and tell the generator polynomial of this shift register to this new node. By this means, when other node joins this network, any node that has obtained an IP address can act as a server to allocate address to this new node. PRDAC can also efficiently avoid IP conflicts and deal with network partition and merge as same as prophet address (PA) allocation and dynamic configuration and distribution protocol (DCDP). Furthermore, PRDAC has less algorithm complexity, less computational complexity and more sufficient assumption than PA. In addition, PRDAC radically avoids address conflicts and maximizes the utilization rate of IP addresses. Analysis and simulation results show that PRDAC has rapid convergence, low overhead and immune from topological structures.

  16. Protocols for data hiding in pseudo-random state

    Science.gov (United States)

    Craver, Scott; Li, Enping; Yu, Jun

    2009-02-01

    An emerging form of steganographic communication uses ciphertext to replace the output of a random or strong pseudo-random number generator. PRNG-driven media, for example computer animated backdrops in video-conferencing channels, can then be used as a covert channel, if the PRNG bits that generated a piece of content can be estimated by the recipient. However, all bits sent over such a channel must be computationally indistinguishable from i.i.d. coin flips. Ciphertext messages and even key exchange datagrams are easily shaped to match this distribution; however, when placing these messages into a continous stream of PRNG bits, the sender is unable to provide synchronization markers, metadata, or error correction to ensure the message's location and proper decoding. In this paper we explore methods for message transmission and steganographic key exchange in such a "coin flip" channel. We establish that key exchange is generally not possible in this channel if an adversary possesses even a modest noise budget. If the warden is not vigilant in adding noise, however, communication is very simple.

  17. PHOEBE: PHysics Of Eclipsing BinariEs

    Science.gov (United States)

    Prsa, Andrej; Matijevic, Gal; Latkovic, Olivera; Vilardell, Francesc; Wils, Patrick

    2011-06-01

    PHOEBE (PHysics Of Eclipsing BinariEs) is a modeling package for eclipsing binary stars, built on top of the widely used WD program (Wilson & Devinney 1971). This introductory paper overviews most important scientific extensions (incorporating observational spectra of eclipsing binaries into the solution-seeking process, extracting individual temperatures from observed color indices, main-sequence constraining and proper treatment of the reddening), numerical innovations (suggested improvements to WD's Differential Corrections method, the new Nelder & Mead's downhill Simplex method) and technical aspects (back-end scripter structure, graphical user interface). While PHOEBE retains 100% WD compatibility, its add-ons are a powerful way to enhance WD by encompassing even more physics and solution reliability.

  18. Distribution of periodic trajectories of C-K systems MIXMAX pseudorandom number generator

    Science.gov (United States)

    Görlich, Andrzej; Kalomenopoulos, Marios; Savvidy, Konstantin; Savvidy, George

    We are considering the hyperbolic C-K systems of Anosov-Kolmogorov which are defined on high dimensional tori and are used to generate pseudorandom numbers for Monte-Carlo simulations. All trajectories of the C-K systems are exponentially unstable and pseudorandom numbers are represented in terms of coordinates of very long chaotic trajectories. The C-K systems on a torus have countable set of everywhere dense periodic trajectories and their distribution play a crucial role in coding and implementation of the pseudorandom number generator. The asymptotic distribution of chaotic trajectories of C-K systems with periods less than a given number is well known in mathematical literature, but a deviation from its asymptotic behavior is unknown. Using analytical and computer calculations, we are studying a distribution function of periodic trajectories and their deviation from asymptotic behavior. The corresponding MIXMAX generator has the best combination of speed, size of the state and is currently available generator.

  19. Non-periodic pseudo-random numbers used in Monte Carlo calculations

    Science.gov (United States)

    Barberis, Gaston E.

    2007-09-01

    The generation of pseudo-random numbers is one of the interesting problems in Monte Carlo simulations, mostly because the common computer generators produce periodic numbers. We used simple pseudo-random numbers generated with the simplest chaotic system, the logistic map, with excellent results. The numbers generated in this way are non-periodic, which we demonstrated for 1013 numbers, and they are obtained in a deterministic way, which allows to repeat systematically any calculation. The Monte Carlo calculations are the ideal field to apply these numbers, and we did it for simple and more elaborated cases. Chemistry and Information Technology use this kind of simulations, and the application of this numbers to quantum Monte Carlo and cryptography is immediate. I present here the techniques to calculate, analyze and use these pseudo-random numbers, show that they lack periodicity up to 1013 numbers and that they are not correlated.

  20. BINERY PSEUDO-RANDOM GRATING AS A STANDARD TEST SURFACE FOR MEASUREMENT OF MODULATION TRANSFER FUNCTION OF INTERFEROMETRIC MICROSCOPES.

    Energy Technology Data Exchange (ETDEWEB)

    YASHCHUK,V.V.; MCKINNEY, W.R.; TAKACS, P.Z.

    2007-08-01

    The task of designing high performance X-ray optical systems requires the development of sophisticated X-ray scattering calculations based on rigorous information about the optics. One of the most insightful approaches to these calculations is based on the power spectral density (PSD) distribution of the surface height. The major problem of measurement of a PSD distribution with an interferometric and/or atomic force microscope arises due to the unknown Modulation Transfer Function (MTF) of the instruments. The MTF characterizes the perturbation of the PSD distribution at higher spatial frequencies. Here, we describe a new method and dedicated test surfaces for calibration of the MTF of a microscope. The method is based on use of a specially designed Binary Pseudo-random (BPR) grating. Comparison of a theoretically calculated PSD spectrum of a BPR grating with a spectrum measured with the grating provides the desired calibration of the instrumental MTF. The theoretical background of the method, as well as results of experimental investigations are presented.

  1. A note on the multiple-recursive matrix method for generating pseudorandom vectors

    OpenAIRE

    Bishoi, Susil Kumar; Haran, Himanshu Kumar; Hasan, Sartaj Ul

    2016-01-01

    The multiple-recursive matrix method for generating pseudorandom vectors was introduced by Niederreiter (Linear Algebra Appl. 192 (1993), 301-328). We propose an algorithm for finding an efficient primitive multiple-recursive matrix method. Moreover, for improving the linear complexity, we introduce a tweak on the contents of the primitive multiple-recursive matrix method.

  2. Pseudo-Random Number Generators for Vector Processors and Multicore Processors

    DEFF Research Database (Denmark)

    Fog, Agner

    2015-01-01

    Large scale Monte Carlo applications need a good pseudo-random number generator capable of utilizing both the vector processing capabilities and multiprocessing capabilities of modern computers in order to get the maximum performance. The requirements for such a generator are discussed. New ways ...

  3. From Pseudorandom Walk to Pseudo-Brownian Motion: First Exit Time from a One-Sided or a Two-Sided Interval

    Directory of Open Access Journals (Sweden)

    Aimé Lachal

    2014-01-01

    Full Text Available Let N be a positive integer, c a positive constant and (ξnn≥1 be a sequence of independent identically distributed pseudorandom variables. We assume that the ξn’s take their values in the discrete set {-N,-N+1,…,N-1,N} and that their common pseudodistribution is characterized by the (positive or negative real numbers ℙ{ξn=k}=δk0+(-1k-1c(2Nk+N for any k∈{-N,-N+1,…,N-1,N}. Let us finally introduce (Snn≥0 the associated pseudorandom walk defined on ℤ by S0=0 and Sn=∑j=1n‍ξj for n≥1. In this paper, we exhibit some properties of (Snn≥0. In particular, we explicitly determine the pseudodistribution of the first overshooting time of a given threshold for (Snn≥0 as well as that of the first exit time from a bounded interval. Next, with an appropriate normalization, we pass from the pseudorandom walk to the pseudo-Brownian motion driven by the high-order heat-type equation ∂/∂t=(-1N-1c∂2N/∂x2N. We retrieve the corresponding pseudodistribution of the first overshooting time of a threshold for the pseudo-Brownian motion (Lachal, 2007. In the same way, we get the pseudodistribution of the first exit time from a bounded interval for the pseudo-Brownian motion which is a new result for this pseudoprocess.

  4. Unraveling the formation history of the black hole X-ray binary LMC X-3 from the zero age main sequence to the present

    Science.gov (United States)

    Sørensen, Mads; Fragos, Tassos; Steiner, James F.; Antoniou, Vallia; Meynet, Georges; Dosopoulou, Fani

    2017-01-01

    Aims: We have endeavoured to understand the formation and evolution of the black hole (BH) X-ray binary LMC X-3. We estimated the properties of the system at four evolutionary stages: (1) at the zero-age main-sequence (ZAMS); (2) immediately before the supernova (SN) explosion of the primary; (3) immediately after the SN; and (4) at the moment when Roche-lobe overflow began. Methods: We used a hybrid approach that combined detailed calculations of the stellar structure and binary evolution with approximate population synthesis models. This allowed us to estimate potential natal kicks and the evolution of the BH spin. We incorporated as model constraints the most up-to-date observational information throughout, which include the binary orbital properties, the companion star mass, effective temperature, surface gravity and radius, and the BH mass and spin. Results: We find at 5% and 95% confidence, respectively, that LMC X-3 began as a ZAMS system with the mass of the primary star in the range M1,ZAMS = 22-31 M⊙ and a secondary star of M2,ZAMS = 5.0-8.3 M⊙, in a wide (PZAMS ≳ 2.000 days) and eccentric (eZAMS ≳ 0.18) orbit. Immediately before the SN, the primary had a mass of M1,preSN = 11.1-18.0 M⊙, but the secondary star was largely unaffected. The orbital period decreased to 0.6-1.7 days and is still eccentric 0 ≤ epreSN ≤ 0.44. We find that a symmetric SN explosion with no or small natal kicks (a few tens of km s-1) imparted on the BH cannot be formally excluded, but large natal kicks in excess of ≳120 km s-1 increase the estimated formation rate by an order of magnitude. Following the SN, the system has a BH MBH,postSN = 6.4-8.2 M⊙ and is set on an eccentric orbit. At the onset of the Roche-lobe overflow, the orbit is circular and has a period of PRLO = 0.8-1.4 days. The full Table 2 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/597/A12

  5. Multiprime Blum-Blum-Shub Pseudorandom Number Generator

    Science.gov (United States)

    2016-09-01

    time pad). For example, suppose our message is M = 1100110. In order to encrypt it, we add a string of random bits, B = 1011010 and Exclusive-Or ( XOR ...GHz Intel Core i5 • Memory: 4 GB 1600 MHz DDR3 • Graphics : Intel HD Graphics 6000 1536 MB We record the time taken to generate 200 sequences for the...Here, the tests are designed to test a null hypothesis H0, which is the hypothesis that the sequences are random. Along with the null hypothesis, the

  6. An efficient parallel pseudorandom bit generator based on an ...

    Indian Academy of Sciences (India)

    complicated floating-point computation and multiplication computation transform into simple shift bit operations are adopted, that not only ensures the nonlinear operations, but also increases the performance efficiency. The PRBG is implemented in software and hardware. The parallel output bit sequences pass all of the ...

  7. Cryptographic applications of analytic number theory complexity lower bounds and pseudorandomness

    CERN Document Server

    2003-01-01

    The book introduces new ways of using analytic number theory in cryptography and related areas, such as complexity theory and pseudorandom number generation. Key topics and features: - various lower bounds on the complexity of some number theoretic and cryptographic problems, associated with classical schemes such as RSA, Diffie-Hellman, DSA as well as with relatively new schemes like XTR and NTRU - a series of very recent results about certain important characteristics (period, distribution, linear complexity) of several commonly used pseudorandom number generators, such as the RSA generator, Blum-Blum-Shub generator, Naor-Reingold generator, inversive generator, and others - one of the principal tools is bounds of exponential sums, which are combined with other number theoretic methods such as lattice reduction and sieving - a number of open problems of different level of difficulty and proposals for further research - an extensive and up-to-date bibliography Cryptographers and number theorists will find th...

  8. Evolution of Close Binary Systems

    Energy Technology Data Exchange (ETDEWEB)

    Yakut, K; Eggleton, P

    2005-01-24

    We collected data on the masses, radii, etc. of three classes of close binary stars: low-temperature contact binaries (LTCBs), near-contact binaries (NCBs), and detached close binaries (DCBs). They restrict themselves to systems where (1) both components are, at least arguably, near the Main Sequence, (2) the periods are less than a day, and (3) there is both spectroscopic and photometric analysis leading to reasonably reliable data. They discuss the possible evolutionary connections between these three classes, emphasizing the roles played by mass loss and angular momentum loss in rapidly-rotating cool stars.

  9. Cognitive Architecture for Direction of Attention Founded on Subliminal Memory Searches, Pseudorandom and Nonstop

    OpenAIRE

    Burger, J.R.

    2008-01-01

    By way of explaining how a brain works logically, human associative memory is modeled with logical and memory neurons, corresponding to standard digital circuits. The resulting cognitive architecture incorporates basic psychological elements such as short term and long term memory. Novel to the architecture are memory searches using cues chosen pseudorandomly from short term memory. Recalls alternated with sensory images, many tens per second, are analyzed subliminally as an ongoing process, ...

  10. Mersenne Twister: A 623-Dimensionally Equidistributed Uniform Pseudo-Random Number Generator

    OpenAIRE

    Matsumoto, Makoto; Nishimura, Takuji

    1998-01-01

    A new algorithm called Mersenne Twister (MT) is proposed for generating uniform pseudorandom numbers. For a particular choice of parameters, the algorithm provides a super astronomical period of 219937 - 1 and 623-dimensional equidistribution up to 32-bit accuracy, while using a working area of only 624 words. This is a new variant of the previously proposed generators, TGFSR, modified so as to admit a Mersenne-prime period. The characteristic polynomial has many terms. The distribution up to...

  11. Interacting binaries

    CERN Document Server

    Shore, S N; van den Heuvel, EPJ

    1994-01-01

    This volume contains lecture notes presented at the 22nd Advanced Course of the Swiss Society for Astrophysics and Astronomy. The contributors deal with symbiotic stars, cataclysmic variables, massive binaries and X-ray binaries, in an attempt to provide a better understanding of stellar evolution.

  12. Optimal pseudorandom sequence selection for online c-VEP based BCI control applications

    DEFF Research Database (Denmark)

    Isaksen, Jonas L.; Mohebbi, Ali; Puthusserypady, Sadasivan

    2017-01-01

    wheelchair control task and completed the same task using stimuli based on the m-code, the gold-code, and the Barker-code. Correct/incorrect identification and time consumption were obtained for each identification. Subject-specific templates were characterized and used in a forward-step first-order model...

  13. EPCGen2 pseudorandom number generators: analysis of J3Gen.

    Science.gov (United States)

    Peinado, Alberto; Munilla, Jorge; Fúster-Sabater, Amparo

    2014-04-09

    This paper analyzes the cryptographic security of J3Gen, a promising pseudo random number generator for low-cost passive Radio Frequency Identification (RFID) tags. Although J3Gen has been shown to fulfill the randomness criteria set by the EPCglobal Gen2 standard and is intended for security applications, we describe here two cryptanalytic attacks that question its security claims: (i) a probabilistic attack based on solving linear equation systems; and (ii) a deterministic attack based on the decimation of the output sequence. Numerical results, supported by simulations, show that for the specific recommended values of the configurable parameters, a low number of intercepted output bits are enough to break J3Gen. We then make some recommendations that address these issues.

  14. EPCGen2 Pseudorandom Number Generators: Analysis of J3Gen

    Directory of Open Access Journals (Sweden)

    Alberto Peinado

    2014-04-01

    Full Text Available This paper analyzes the cryptographic security of J3Gen, a promising pseudo random number generator for low-cost passive Radio Frequency Identification (RFID tags. Although J3Gen has been shown to fulfill the randomness criteria set by the EPCglobal Gen2 standard and is intended for security applications, we describe here two cryptanalytic attacks that question its security claims: (i a probabilistic attack based on solving linear equation systems; and (ii a deterministic attack based on the decimation of the output sequence. Numerical results, supported by simulations, show that for the specific recommended values of the configurable parameters, a low number of intercepted output bits are enough to break J3Gen. We then make some recommendations that address these issues.

  15. XMM-NEWTON MONITORING OF THE CLOSE PRE-MAIN-SEQUENCE BINARY AK SCO. EVIDENCE OF TIDE-DRIVEN FILLING OF THE INNER GAP IN THE CIRCUMBINARY DISK

    Energy Technology Data Exchange (ETDEWEB)

    Gomez de Castro, Ana Ines [S. D. Astronomia y Geodesia and Instituto de Matematica Interdisciplinar, Fac. de CC Matematicas, Universidad Complutense, E-28040 Madrid (Spain); Lopez-Santiago, Javier [Departamento de Astrofisica, Fac de CC Fisicas, Universidad Complutense, E-28040 Madrid (Spain); Talavera, Antonio [European Space Astronomy Center, Villanueva de la Canada, E-28691, Madrid (Spain); Sytov, A. Yu.; Bisikalo, D. [Institute of Astronomy of the Russian Academy of Sciences, Pyatnitskaya St. 48, 109017 Moscow (Russian Federation)

    2013-03-20

    AK Sco stands out among pre-main-sequence binaries because of its prominent ultraviolet excess, the high eccentricity of its orbit, and the strong tides driven by it. AK Sco consists of two F5-type stars that get as close as 11 R{sub *} at periastron passage. The presence of a dense (n{sub e} {approx} 10{sup 11} cm{sup -3}) extended envelope has been unveiled recently. In this article, we report the results from an XMM-Newton-based monitoring of the system. We show that at periastron, X-ray and UV fluxes are enhanced by a factor of {approx}3 with respect to the apastron values. The X-ray radiation is produced in an optically thin plasma with T {approx} 6.4 Multiplication-Sign 10{sup 6} K and it is found that the N{sub H} column density rises from 0.35 Multiplication-Sign 10{sup 21} cm{sup -2} at periastron to 1.11 Multiplication-Sign 10{sup 21} cm{sup -2} at apastron, in good agreement with previous polarimetric observations. The UV emission detected in the Optical Monitor band seems to be caused by the reprocessing of the high-energy magnetospheric radiation on the circumstellar material. Further evidence of the strong magnetospheric disturbances is provided by the detection of line broadening of 278.7 km s{sup -1} in the N V line with Hubble Space Telescope/Space Telescope Imaging Spectrograph. Numerical simulations of the mass flow from the circumbinary disk to the components have been carried out. They provide a consistent scenario with which to interpret AK Sco observations. We show that the eccentric orbit acts like a gravitational piston. At apastron, matter is dragged efficiently from the inner disk border, filling the inner gap and producing accretion streams that end as ring-like structures around each component of the system. At periastron, the ring-like structures come into contact, leading to angular momentum loss, and thus producing an accretion outburst.

  16. Pseudo-random Aloha for inter-frame soft combining in RFID systems

    DEFF Research Database (Denmark)

    Castiglione, Paolo; Ricciato, Fabio; Popovski, Petar

    2013-01-01

    In this work we consider a recently proposed variant of the classical Framed Slotted-ALOHA where slot selection is based on a pseudo-random function of the message to be transmitted and of the frame index. We couple this feature with convolutional encoding, that allows to perform Inter-frame Soft...... cancellation (instead of combining). Numerical simulation results show that the ISoC scheme brings a noticeable throughput gain over traditional schemes in a dense RFID scenario with multiple concurrent Tag transmissions....

  17. Pseudo-random tool paths for CNC sub-aperture polishing and other applications.

    Science.gov (United States)

    Dunn, Christina R; Walker, David D

    2008-11-10

    In this paper we first contrast classical and CNC polishing techniques in regard to the repetitiveness of the machine motions. We then present a pseudo-random tool path for use with CNC sub-aperture polishing techniques and report polishing results from equivalent random and raster tool-paths. The random tool-path used - the unicursal random tool-path - employs a random seed to generate a pattern which never crosses itself. Because of this property, this tool-path is directly compatible with dwell time maps for corrective polishing. The tool-path can be used to polish any continuous area of any boundary shape, including surfaces with interior perforations.

  18. The Meritfactor of Binary Seqences

    DEFF Research Database (Denmark)

    Høholdt, Tom

    1999-01-01

    Binary sequences with small aperiodic correlations play an important role in many applications ranging from radar to modulation and testing of systems. Golay(1977) introduced the merit factor as a measure of the goodness of the sequence and conjectured an upper bound for this. His conjecture...

  19. Comparison of a quantum random number generator with pseudorandom number generators for their use in molecular Monte Carlo simulations.

    Science.gov (United States)

    Ghersi, Dario; Parakh, Abhishek; Mezei, Mihaly

    2017-12-05

    Four pseudorandom number generators were compared with a physical, quantum-based random number generator using the NIST suite of statistical tests, which only the quantum-based random number generator could successfully pass. We then measured the effect of the five random number generators on various calculated properties in different Markov-chain Monte Carlo simulations. Two types of systems were tested: conformational sampling of a small molecule in aqueous solution and liquid methanol under constant temperature and pressure. The results show that poor quality pseudorandom number generators produce results that deviate significantly from those obtained with the quantum-based random number generator, particularly in the case of the small molecule in aqueous solution setup. In contrast, the widely used Mersenne Twister pseudorandom generator and a 64-bit Linear Congruential Generator with a scrambler produce results that are statistically indistinguishable from those obtained with the quantum-based random number generator. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  20. Astrometric Binaries: White Dwarfs?

    Science.gov (United States)

    Oliversen, Nancy A.

    We propose to observe a selection of astrometric or spectroscopicastrometric binaries nearer than about 20 pc with unseen low mass companions. Systems of this type are important for determining the luminosity function of low mass stars (white dwarfs and very late main sequence M stars), and their contribution to the total mass of the galaxy. Systems of this type are also important because the low mass, invisible companions are potential candidates in the search for planets. Our target list is selected primarily from the list of 31 astrometric binaries near the sun by Lippincott (1978, Space Sci. Rev., 22, 153), with additional candidates from recent observations by Kamper. The elimination of stars with previous IUE observations, red companions resolved by infrared speckle interferometry, or primaries later than M1 (because if white dwarf companions are present they should have been detected in the visible region) reduces the list to 5 targets which need further information. IUE SWP low dispersion observations of these targets will show clearly whether the remaining unseen companions are white dwarfs, thus eliminating very cool main sequence stars or planets. This is also important in providing complete statistical information about the nearest stars. The discovery of a white dwarf in such a nearby system would provide important additional information about the masses of white dwarfs. Recent results by Greenstein (1986, A. J., 92, 859) from binary systems containing white dwarfs imply that 80% of such systems are as yet undetected. The preference of binaries for companions of approximately equal mass makes the Lippincott-Kamper list of A through K primaries with unseen companions a good one to use to search for white dwarfs. The mass and light dominance of the current primary over the white dwarf in the visible makes ultraviolet observations essential to obtain an accurate census of white dwarf binaries.

  1. Improving the pseudo-randomness properties of chaotic maps using deep-zoom.

    Science.gov (United States)

    Machicao, Jeaneth; Bruno, Odemir M

    2017-05-01

    A generalized method is proposed to compose new orbits from a given chaotic map. The method provides an approach to examine discrete-time chaotic maps in a "deep-zoom" manner by using k-digits to the right from the decimal separator of a given point from the underlying chaotic map. Interesting phenomena have been identified. Rapid randomization was observed, i.e., chaotic patterns tend to become indistinguishable when compared to the original orbits of the underlying chaotic map. Our results were presented using different graphical analyses (i.e., time-evolution, bifurcation diagram, Lyapunov exponent, Poincaré diagram, and frequency distribution). Moreover, taking advantage of this randomization improvement, we propose a Pseudo-Random Number Generator (PRNG) based on the k-logistic map. The pseudo-random qualities of the proposed PRNG passed both tests successfully, i.e., DIEHARD and NIST, and were comparable with other traditional PRNGs such as the Mersenne Twister. The results suggest that simple maps such as the logistic map can be considered as good PRNG methods.

  2. Generalized hardware post-processing technique for chaos-based pseudorandom number generators

    KAUST Repository

    Barakat, Mohamed L.

    2013-06-01

    This paper presents a generalized post-processing technique for enhancing the pseudorandomness of digital chaotic oscillators through a nonlinear XOR-based operation with rotation and feedback. The technique allows full utilization of the chaotic output as pseudorandom number generators and improves throughput without a significant area penalty. Digital design of a third-order chaotic system with maximum function nonlinearity is presented with verified chaotic dynamics. The proposed post-processing technique eliminates statistical degradation in all output bits, thus maximizing throughput compared to other processing techniques. Furthermore, the technique is applied to several fully digital chaotic oscillators with performance surpassing previously reported systems in the literature. The enhancement in the randomness is further examined in a simple image encryption application resulting in a better security performance. The system is verified through experiment on a Xilinx Virtex 4 FPGA with throughput up to 15.44 Gbit/s and logic utilization less than 0.84% for 32-bit implementations. © 2013 ETRI.

  3. Binary effectivity rules

    DEFF Research Database (Denmark)

    Keiding, Hans; Peleg, Bezalel

    2006-01-01

    is binary if it is rationalized by an acyclic binary relation. The foregoing result motivates our definition of a binary effectivity rule as the effectivity rule of some binary SCR. A binary SCR is regular if it satisfies unanimity, monotonicity, and independence of infeasible alternatives. A binary...

  4. Goal-independent mechanisms for free response generation: creative and pseudo-random performance share neural substrates.

    Science.gov (United States)

    de Manzano, Örjan; Ullén, Fredrik

    2012-01-02

    To what extent free response generation in different tasks uses common and task-specific neurocognitive processes has remained unclear. Here, we investigated overlap and differences in neural activity during musical improvisation and pseudo-random response generation. Brain activity was measured using fMRI in a group of professional classical pianists, who performed musical improvisation of melodies, pseudo-random key-presses and a baseline condition (sight-reading), on either two, six or twelve keys on a piano keyboard. The results revealed an extensive overlap in neural activity between the two generative conditions. Active regions included the dorsolateral and dorsomedial prefrontal cortices, inferior frontal gyrus, anterior cingulate cortex and pre-SMA. No regions showed higher activity in improvisation than in pseudo-random generation. These findings suggest that the activated regions fulfill generic functions that are utilized in different types of free generation tasks, independent of overall goal. In contrast, pseudo-random generation was accompanied by higher activity than improvisation in several regions. This presumably reflects the participants' musical expertise as well as the pseudo-random generation task's high load on attention, working memory, and executive control. The results highlight the significance of using naturalistic tasks to study human behavior and cognition. No brain activity was related to the size of the response set. We discuss that this may reflect that the musicians were able to use specific strategies for improvisation, by which there was no simple relationship between response set size and neural activity. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. Computer controlled evaluation of binary images

    NARCIS (Netherlands)

    Schouten, Th.E.; van den Broek, Egon

    2010-01-01

    The present invention relates to computer controlled image processing and, in particular, to computer controlled evaluation of two dimensional, 2D, and three dimensional, 3D, binary images including sequences of images using a distance map.

  6. The VLT-FLAMES Tarantula Survey. XXVII. Physical parameters of B-type main-sequence binary systems in the Tarantula nebula

    Science.gov (United States)

    Garland, R.; Dufton, P. L.; Evans, C. J.; Crowther, P. A.; Howarth, I. D.; de Koter, A.; de Mink, S. E.; Grin, N. J.; Langer, N.; Lennon, D. J.; McEvoy, C. M.; Sana, H.; Schneider, F. R. N.; Símon Díaz, S.; Taylor, W. D.; Thompson, A.; Vink, J. S.

    2017-07-01

    A spectroscopic analysis has been undertaken for the B-type multiple systems (excluding those with supergiant primaries) in the VLT-FLAMES Tarantula Survey (VFTS). Projected rotational velocities, vesini, for the primaries have been estimated using a Fourier Transform technique and confirmed by fitting rotationally broadened profiles. A subset of 33 systems with vesini ≤ 80 km s-1 have been analysed using a TLUSTY grid of model atmospheres to estimate stellar parameters and surface abundances for the primaries. The effects of a potential flux contribution from an unseen secondary have also been considered. For 20 targets it was possible to reliably estimate their effective temperatures (Teff) but for the other 13 objects it was only possible to provide a constraint of 20 000 ≤ Teff ≤ 26 000 K - the other parameters estimated for these targets will be consequently less reliable. The estimated stellar properties are compared with evolutionary models and are generally consistent with their membership of 30 Doradus, while the nature of the secondaries of 3 SB2 system is discussed. A comparison with a sample of single stars with vesini ≤ 80 km s-1 obtained from the VFTS and analysed with the same techniques implies that the atmospheric parameters and nitrogen abundances of the two samples are similar. However, the binary sample may have a lack of primaries with significant nitrogen enhancements, which would be consistent with them having low rotational velocities and having effectively evolved as single stars without significant rotational mixing. This result, which may be actually a consequence of the limitations of the pathfinder investigation presented in this paper, should be considered as a motivation for spectroscopic abundance analysis of large samples of binary stars, with high quality observational data. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programme 182.D-0222.Tables

  7. The Young Visual Binary Survey

    Science.gov (United States)

    Prato, Lisa; Avilez, Ian; Lindstrom, Kyle; Graham, Sean; Sullivan, Kendall; Biddle, Lauren; Skiff, Brian; Nofi, Larissa; Schaefer, Gail; Simon, Michal

    2018-01-01

    Differences in the stellar and circumstellar properties of the components of young binaries provide key information about star and disk formation and evolution processes. Because objects with separations of a few to a few hundred astronomical units share a common environment and composition, multiple systems allow us to control for some of the factors which play into star formation. We are completing analysis of a rich sample of about 100 pre-main sequence binaries and higher order multiples, primarily located in the Taurus and Ophiuchus star forming regions. This poster will highlight some of out recent, exciting results. All reduced spectra and the results of our analysis will be publicly available to the community at http://jumar.lowell.edu/BinaryStars/. Support for this research was provided in part by NSF award AST-1313399 and by NASA Keck KPDA funding.

  8. Visual-vestibular interaction during head-free pursuit of pseudorandom target motion in man.

    Science.gov (United States)

    Waterston, J A; Barnes, G R

    1992-01-01

    Recordings of head and eye movement were made during pursuit of mixed-frequency, pseudorandom target motion to study the mechanism of vestibulo-ocular reflex (VOR) suppression during head-free pursuit. When high velocity stimuli were used, slow-phase gaze velocity gains decreased significantly with increases in both absolute target velocity and the velocity ratio between the frequency components. These changes occurred independently of changes in the head displacement gain, which remained relatively constant at the lower frequency and were directly attributable to impaired suppression of the VOR. Similar effects were seen when visual feedback was degraded by tachistoscopic illumination of the target. The results indicate that visual feedback, rather than an efference copy of the head velocity signal, is essential for suppression of slow-phase vestibular eye movement during head-free pursuit. When head-free and head-fixed pursuit were compared, striking similarities were seen for both slow phase gaze velocity gain and phase, indicating that gaze control during smooth pursuit is largely independent of the degree of associated head movement. This suggests that the VOR is not switched off during head-free pursuit. An estimate of the underlying VOR gain was obtained by recording the vestibular response produced by active head movements in darkness. The rather higher estimates of VOR gain obtained using an imaginary earth-fixed target paradigm were found to predict head-free gains more closely than the gains obtained during imaginary pursuit of a moving target, suggesting that such measures may be more representative of the underlying VOR gain.

  9. Psychoacoustic Properties of Fibonacci Sequences

    Directory of Open Access Journals (Sweden)

    J. Sokoll

    2008-01-01

    Full Text Available 1202, Fibonacci set up one of the most interesting sequences in number theory. This sequence can be represented by so-called Fibonacci Numbers, and by a binary sequence of zeros and ones. If such a binary Fibonacci Sequence is played back as an audio file, a very dissonant sound results. This is caused by the “almost-periodic”, “self-similar” property of the binary sequence. The ratio of zeros and ones converges to the golden ratio, as do the primary and secondary spectral components intheir frequencies and amplitudes. These Fibonacci Sequences will be characterized using listening tests and psychoacoustic analyses. 

  10. On the short-term predictability of fully digital chaotic oscillators for pseudo-random number generation

    KAUST Repository

    Radwan, Ahmed Gomaa

    2014-06-18

    This paper presents a digital implementation of a 3rd order chaotic system using the Euler approximation. Short-term predictability is studied in relation to system precision, Euler step size and attractor size and optimal parameters for maximum performance are derived. Defective bits from the native chaotic output are neglected and the remaining pass the NIST SP. 800-22 tests without post-processing. The resulting optimized pseudorandom number generator has throughput up to 17.60 Gbits/s for a 64-bit design experimentally verified on a Xilinx Virtex 4 FPGA with logic utilization less than 1.85%.

  11. Pseudo-Random Mating Populations. in Celebration of the 80th Anniversary of the Hardy-Weinberg Law

    OpenAIRE

    Li, C. C.

    1988-01-01

    That random mating leads to Hardy-Weinberg distribution of genotypes is well known. This report is to show that, if the deviations from random mating are of a certain pattern, the offspring generation will also be in Hardy-Weinberg proportions. This brings out the fact that random mating is a sufficient condition, not a necessary one, for the attainment of the Hardy-Weinberg proportions. Such nonrandom-mating populations are tentatively said to be pseudo-random mating. Pseudo-random-mating po...

  12. Detection of M-Sequences from Spike Sequence in Neuronal Networks

    Directory of Open Access Journals (Sweden)

    Yoshi Nishitani

    2012-01-01

    Full Text Available In circuit theory, it is well known that a linear feedback shift register (LFSR circuit generates pseudorandom bit sequences (PRBS, including an M-sequence with the maximum period of length. In this study, we tried to detect M-sequences known as a pseudorandom sequence generated by the LFSR circuit from time series patterns of stimulated action potentials. Stimulated action potentials were recorded from dissociated cultures of hippocampal neurons grown on a multielectrode array. We could find several M-sequences from a 3-stage LFSR circuit (M3. These results show the possibility of assembling LFSR circuits or its equivalent ones in a neuronal network. However, since the M3 pattern was composed of only four spike intervals, the possibility of an accidental detection was not zero. Then, we detected M-sequences from random spike sequences which were not generated from an LFSR circuit and compare the result with the number of M-sequences from the originally observed raster data. As a result, a significant difference was confirmed: a greater number of “0–1” reversed the 3-stage M-sequences occurred than would have accidentally be detected. This result suggests that some LFSR equivalent circuits are assembled in neuronal networks.

  13. Binary Masking & Speech Intelligibility

    DEFF Research Database (Denmark)

    Boldt, Jesper

    experiments under ideal conditions or as experiments under more realistic conditions useful for real-life applications such as hearing aids. In the experiments under ideal conditions, the previously defined ideal binary mask is evaluated using hearing impaired listeners, and a novel binary mask -- the target...... binary mask -- is introduced. The target binary mask shows the same substantial increase in intelligibility as the ideal binary mask and is proposed as a new reference for binary masking. In the category of real-life applications, two new methods are proposed: a method for estimation of the ideal binary...... mask using a directional system and a method for correcting errors in the target binary mask. The last part of the thesis, proposes a new method for objective evaluation of speech intelligibility....

  14. Pseudo-random data acquisition geometry in 3D seismic survey; Sanjigen jishin tansa ni okeru giji random data shutoku reiauto ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Minegishi, M.; Tsuburaya, Y. [Japan National Oil Corp., Tokyo (Japan). Technology Research Center

    1996-10-01

    Influence of pseudo-random geometry on the imaging for 3D seismic exploration data acquisition has been investigate using a simple model by comparing with the regular geometry. When constituting wave front by the interference of elemental waves, pseudo-random geometry data did not always provide good results. In the case of a point diffractor, the imaging operation, where the constituted wave front was returned to the point diffractor by the interference of elemental waves for the spatial alias records, did not always give clear images. In the case of multi point diffractor, good images were obtained with less noise generation in spite of alias records. There are a lot of diffractors in the actual geological structures, which corresponds to the case of multi point diffractors. Finally, better images could be obtained by inputting records acquired using the pseudo-random geometry rather than by inputting spatial alias records acquired using the regular geometry. 7 refs., 6 figs.

  15. Solving a Binary Puzzle

    NARCIS (Netherlands)

    P.H. Utomo (Putranto); R.H. Makarim (Rusydi)

    2017-01-01

    textabstractA Binary puzzle is a Sudoku-like puzzle with values in each cell taken from the set (Formula presented.). Let (Formula presented.) be an even integer, a solved binary puzzle is an (Formula presented.) binary array that satisfies the following conditions: (1) no three consecutive ones and

  16. Eclipsing binaries in open clusters

    DEFF Research Database (Denmark)

    Southworth, John; Clausen, J.V.

    2006-01-01

    Stars: fundamental parameters - Stars : binaries : eclipsing - Stars: Binaries: spectroscopic - Open clusters and ass. : general Udgivelsesdato: 5 August......Stars: fundamental parameters - Stars : binaries : eclipsing - Stars: Binaries: spectroscopic - Open clusters and ass. : general Udgivelsesdato: 5 August...

  17. Sadhana | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Sadhana; Volume 34; Issue 5. Issue front cover thumbnail. Volume 34, Issue 5. October 2009, pages 689-864. pp 689-701. Cryptographic pseudo-random sequences from the chaotic Hénon map · Madhekar Suneel · More Details Abstract Fulltext PDF. A scheme for pseudo-random binary sequence ...

  18. A novel effect of Noscapine on patients with massive ischemic stroke: A pseudo-randomized clinical trial.

    Science.gov (United States)

    Mahmoudian, Massoud; Rezvani, Mohammad; Rohani, Mohammad; Benaissa, Foozya; Jalili, Mehdi; Ghourchian, Shadi

    2015-01-05

    Massive ischemic stroke causes significant mortality and morbidity in stroke patients. The main treatments for massive ischemic stroke are recombinant tissue plasminogen activator (rtPA), craniotomy, and endovascular interventions. Due to destructive effects of bradykinin on the nervous system in ischemic stroke, it seems reasonable that using Noscapine as a Bradykinin antagonist may improve patients' outcome after ischemic stroke. The effect of Noscapine on massive ischemic stroke was shown by the previous pilot study by our group. This pseudo-randomized clinical trial study was designed to assess the result of the pilot study. Patients who had clinical symptoms or computed tomography scan indicative of massive stroke (in full middle cerebral artery territory) were entered to the study. The cases received the drugs according to their turns in emergency ward (pseudo-randomized). The patient group received Noscapine, and the control group received common supportive treatments. The patients and data analyzer were blinded about the data. At the end of the study, to adjust confounding variables we used logistic regression. After 1-month follow-up, 16 patients in the control group and 11 patients in the case group expired (P = 0.193). Analyzing the data extracted from Rankin scale and Barthel index check lists, revealed no significant differences in the two groups. Despite the absence of significant statistical results in our study, the reduction rate of 16% for mortality rate in Noscapine recipients is clinically remarkable and motivates future studies with larger sample sizes.

  19. Light Curve Solutions of Eclipsing Binaries in the Large Magellanic Cloud

    Science.gov (United States)

    Rawls, Meredith L.; Rao, M. S.

    2012-01-01

    We present model light curves for nine eclipsing binary stars in the Large Magellanic Cloud (LMC). These systems are detached binaries with nearly circular orbits, and were pseudorandomly selected from three of 21 LMC regions in the Optical Gravitational Lensing Experiment II (OGLE-II) survey. We make use of light curves, orbital periods, and binary classification as reported in Wyrzykowski et al. (2003). We present light curve solutions created with the software PHysics Of Eclipsing BinariEs (PHOEBE, Prsa & Zwitter 2005). Each solution has the best-fit mass ratio q, system inclination i, component temperatures T1 and T2, and modified Kopal potentials Ω1 and Ω2. PHOEBE employs a Nelder & Mead's Simplex fitting method that adjusts all the input parameters to find the best fit to the light curve. Many of the light curves have significant scatter, which can lead to multiple degenerate best-fit solutions, and we discuss what can be done in the future to refine our results, derive global stellar parameters, and place these nine systems in a larger context. We acknowledge the support of the International Research Experience for Students (IRES) program, which is sponsored by the NSF and administered by NSO/GONG.

  20. General simulation algorithm for autocorrelated binary processes

    Science.gov (United States)

    Serinaldi, Francesco; Lombardo, Federico

    2017-02-01

    The apparent ubiquity of binary random processes in physics and many other fields has attracted considerable attention from the modeling community. However, generation of binary sequences with prescribed autocorrelation is a challenging task owing to the discrete nature of the marginal distributions, which makes the application of classical spectral techniques problematic. We show that such methods can effectively be used if we focus on the parent continuous process of beta distributed transition probabilities rather than on the target binary process. This change of paradigm results in a simulation procedure effectively embedding a spectrum-based iterative amplitude-adjusted Fourier transform method devised for continuous processes. The proposed algorithm is fully general, requires minimal assumptions, and can easily simulate binary signals with power-law and exponentially decaying autocorrelation functions corresponding, for instance, to Hurst-Kolmogorov and Markov processes. An application to rainfall intermittency shows that the proposed algorithm can also simulate surrogate data preserving the empirical autocorrelation.

  1. Interacting binary stars

    CERN Document Server

    Sahade, Jorge; Ter Haar, D

    1978-01-01

    Interacting Binary Stars deals with the development, ideas, and problems in the study of interacting binary stars. The book consolidates the information that is scattered over many publications and papers and gives an account of important discoveries with relevant historical background. Chapters are devoted to the presentation and discussion of the different facets of the field, such as historical account of the development in the field of study of binary stars; the Roche equipotential surfaces; methods and techniques in space astronomy; and enumeration of binary star systems that are studied

  2. Pseudo-random mating populations. In celebration of the 80th anniversary of the Hardy-Weinberg law.

    Science.gov (United States)

    Li, C C

    1988-07-01

    That random mating leads to Hardy-Weinberg distribution of genotypes is well known. This report is to show that, if the deviations from random mating are of a certain pattern, the offspring generation will also be in Hardy-Weinberg proportions. This brings out the fact that random mating is a sufficient condition, not a necessary one, for the attainment of the Hardy-Weinberg proportions. Such nonrandom-mating populations are tentatively said to be pseudo-random mating. Pseudo-random-mating populations exist for both autosomal and sex-linked systems with two or multiple alleles. This report covers the basic case of a two-allele autosomal locus in detail, but the possible extension to two loci and cytonuclear systems have also been mentioned in discussion.

  3. Massive binary evolution

    Science.gov (United States)

    Podsiadlowski, Philipp

    2010-03-01

    Understanding the evolution of massive binaries is essential for understanding many observed classes of stellar systems, ranging from Algols to X-ray binaries, recycled pulsars, double-neutron-star systems and quite possibly gamma-ray burst sources. Here recent progress and some of the main remaining uncertainties are being reviewed, particularly emphasizing stellar mergers and their possible implications for supernovae like SN 1987A, Thorne-Żytkow objects and η Car-like eruptions. It is shown how binary evolution can affect both the envelope and the core structure of a massive star, explaining - at least in part - the observed diversity of core-collapse supernovae and potentially producing different kick distributions for systems in binaries. Various ideas linking gamma-ray bursts to massive binaries are also being discussed.

  4. Rapid Acquisition of Choice and Timing and the Provenance of the Terminal-Link Effect

    Science.gov (United States)

    Kyonka, Elizabeth G. E.; Grace, Randolph C.

    2010-01-01

    Eight pigeons responded in a concurrent-chains procedure in which terminal-link schedules changed pseudorandomly across sessions. Pairs of terminal-link delays either summed to 15 s or to 45 s. Across sessions, the location of the shorter terminal link changed according to a pseudorandom binary sequence. On some terminal links, food was withheld…

  5. The Contact Binary System Ty-Booti

    Science.gov (United States)

    Rainger, P. P.; Hilditch, R. W.; Bell, S. A.

    1990-09-01

    Radial velocities of the contact binary system TY Boo are presented for the first time. Orbital solutions for both components are combined with an analysis of the B lightcurve data published by Samec & Bookmyer to yield masses and absolute dimensions for the components. It is shown that the system is a normal W-type shallow-contact binary, with the primary as a main-sequence star and the secondary ≃ 1.4 times larger than expected for its ZAMS mass. A survey of published times of minima confirms that the system has undergone significant changes in orbital period during this century, but that currently it is in a stable state.

  6. A Computational Guide to Physics of Eclipsing Binaries. Paper I. Demonstrations and Perspectives

    OpenAIRE

    Prsa, A.; Zwitter, T.

    2005-01-01

    PHOEBE (PHysics Of Eclipsing BinariEs) is a modeling package for eclipsing binary stars, built on top of the widely used WD program (Wilson & Devinney 1971). This introductory paper overviews most important scientific extensions (incorporating observational spectra of eclipsing binaries into the solution-seeking process, extracting individual temperatures from observed color indices, main-sequence constraining and proper treatment of the reddening), numerical innovations (suggested improvemen...

  7. Fully digital jerk-based chaotic oscillators for high throughput pseudo-random number generators up to 8.77Gbits/s

    KAUST Repository

    Mansingka, Abhinav S.

    2014-06-18

    This paper introduces fully digital implementations of four di erent systems in the 3rd order jerk-equation based chaotic family using the Euler approximation. The digitization approach enables controllable chaotic systems that reliably provide sinusoidal or chaotic output based on a selection input. New systems are introduced, derived using logical and arithmetic operations between two system implementations of different bus widths, with up to 100x higher maximum Lyapunov exponent than the original jerkequation based chaotic systems. The resulting chaotic output is shown to pass the NIST sp. 800-22 statistical test suite for pseudorandom number generators without post-processing by only eliminating the statistically defective bits. The systems are designed in Verilog HDL and experimentally verified on a Xilinx Virtex 4 FPGA for a maximum throughput of 15.59 Gbits/s for the native chaotic output and 8.77 Gbits/s for the resulting pseudo-random number generators.

  8. BINARY MINOR PLANETS

    Data.gov (United States)

    National Aeronautics and Space Administration — The data set lists orbital and physical properties for well-observed or suspected binary/multiple minor planets including the Pluto system, compiled from the...

  9. Binary and Millisecond Pulsars

    OpenAIRE

    Lorimer, D. R.

    2005-01-01

    We review the main properties, demographics and applications of binary and millisecond radio pulsars. Our knowledge of these exciting objects has greatly increased in recent years, mainly due to successful surveys which have brought the known pulsar population to over 1800. There are now 83 binary and millisecond pulsars associated with the disk of our Galaxy, and a further 140 pulsars in 26 of the Galactic globular clusters. Recent highlights include the discovery of the young relativistic b...

  10. The Methods of Implementation of the Three-dimensional Pseudorandom Number Generator DOZEN for Heterogeneous CPU/GPU /FPGA High-performance Systems

    Directory of Open Access Journals (Sweden)

    Nikolay Petrovich Vasilyev

    2015-03-01

    Full Text Available The paper describes the scope of information security protocols based on PRN G in industrial systems. A method for implementing three-dimensional pseudorandom number generator D O Z E N in hybrid systems is provided. The description and results of studies parallel CUDA-version of the algorithm for use in hybrid data centers and high-performance FPGA-version for use in hardware solutions in controlled facilities of SCADA-systems are given.

  11. Astrophysics of white dwarf binaries

    NARCIS (Netherlands)

    Nelemans, G.A.

    2006-01-01

    White dwarf binaries are the most common compact binaries in the Universe and are especially important for low-frequency gravitational wave detectors such as LISA. There are a number of open questions about binary evolution and the Galactic population of white dwarf binaries that can be solved using

  12. Distribution of some sequences of points on elliptic curves

    DEFF Research Database (Denmark)

    Lange, Tanja; Shparlinski, Igor

    2007-01-01

    We estimate character sums over points on elliptic curves over a finite field of q elements. Pseudorandom sequences can be constructed by taking linear combinations with small coefficients (for example, from the set {−1, 0, 1}) of a fixed vector of points, which forms the seed of the generator. We...... consider several particular cases of this general approach which are of special practical interest and have occurred in the literature. For each of them we show that the resulting sequence has good uniformity of distribution properties....

  13. Accreting Black Hole Binaries in Globular Clusters

    Science.gov (United States)

    Kremer, Kyle; Chatterjee, Sourav; Rodriguez, Carl L.; Rasio, Frederic A.

    2018-01-01

    We explore the formation of mass-transferring binary systems containing black holes (BHs) within globular clusters (GC). We show that it is possible to form mass-transferring BH binaries with main sequence, giant, and white dwarf companions with a variety of orbital parameters in GCs spanning a large range in present-day properties. All mass-transferring BH binaries found in our models at late times are dynamically created. The BHs in these systems experienced a median of ∼30 dynamical encounters within the cluster before and after acquiring the donor. Furthermore, we show that the presence of mass-transferring BH systems has little correlation with the total number of BHs within the cluster at any time. This is because the net rate of formation of BH–non-BH binaries in a cluster is largely independent of the total number of retained BHs. Our results suggest that the detection of a mass-transferring BH binary in a GC does not necessarily indicate that the host cluster contains a large BH population.

  14. A cubic map chaos criterion theorem with applications in generalized synchronization based pseudorandom number generator and image encryption

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xiuping, E-mail: yangxiuping-1990@163.com; Min, Lequan, E-mail: minlequan@sina.com; Wang, Xue, E-mail: wangxue-20130818@163.com [Schools of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083 (China)

    2015-05-15

    This paper sets up a chaos criterion theorem on a kind of cubic polynomial discrete maps. Using this theorem, Zhou-Song's chaos criterion theorem on quadratic polynomial discrete maps and generalized synchronization (GS) theorem construct an eight-dimensional chaotic GS system. Numerical simulations have been carried out to verify the effectiveness of theoretical results. The chaotic GS system is used to design a chaos-based pseudorandom number generator (CPRNG). Using FIPS 140-2 test suit/Generalized FIPS 140-2, test suit tests the randomness of two 1000 key streams consisting of 20 000 bits generated by the CPRNG, respectively. The results show that there are 99.9%/98.5% key streams to have passed the FIPS 140-2 test suit/Generalized FIPS 140-2 test. Numerical simulations show that the different keystreams have an average 50.001% same codes. The key space of the CPRNG is larger than 2{sup 1345}. As an application of the CPRNG, this study gives an image encryption example. Experimental results show that the linear coefficients between the plaintext and the ciphertext and the decrypted ciphertexts via the 100 key streams with perturbed keys are less than 0.00428. The result suggests that the decrypted texts via the keystreams generated via perturbed keys of the CPRNG are almost completely independent on the original image text, and brute attacks are needed to break the cryptographic system.

  15. Adiabatic Mass Loss Model in Binary Stars

    Science.gov (United States)

    Ge, H. W.

    2012-07-01

    Rapid mass transfer process in the interacting binary systems is very complicated. It relates to two basic problems in the binary star evolution, i.e., the dynamically unstable Roche-lobe overflow and the common envelope evolution. Both of the problems are very important and difficult to be modeled. In this PhD thesis, we focus on the rapid mass loss process of the donor in interacting binary systems. The application to the criterion of dynamically unstable mass transfer and the common envelope evolution are also included. Our results based on the adiabatic mass loss model could be used to improve the binary evolution theory, the binary population synthetic method, and other related aspects. We build up the adiabatic mass loss model. In this model, two approximations are included. The first one is that the energy generation and heat flow through the stellar interior can be neglected, hence the restructuring is adiabatic. The second one is that he stellar interior remains in hydrostatic equilibrium. We model this response by constructing model sequences, beginning with a donor star filling its Roche lobe at an arbitrary point in its evolution, holding its specific entropy and composition profiles fixed. These approximations are validated by the comparison with the time-dependent binary mass transfer calculations and the polytropic model for low mass zero-age main-sequence stars. In the dynamical time scale mass transfer, the adiabatic response of the donor star drives it to expand beyond its Roche lobe, leading to runaway mass transfer and the formation of a common envelope with its companion star. For donor stars with surface convection zones of any significant depth, this runaway condition is encountered early in mass transfer, if at all; but for main sequence stars with radiative envelopes, it may be encountered after a prolonged phase of thermal time scale mass transfer, so-called delayed dynamical instability. We identify the critical binary mass ratio for the

  16. Counting sequences, Gray codes and lexicodes

    NARCIS (Netherlands)

    Suparta, I.N.

    2006-01-01

    A counting sequence of length n is a list of all 2^n binary n-tuples (binary codewords of length n). The number of bit positions where two codewords differ is called the Hamming distance of these two codewords. The average Hamming distance of a counting sequence of length n is defined as the average

  17. Skewed Binary Search Trees

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Moruz, Gabriel

    2006-01-01

    It is well-known that to minimize the number of comparisons a binary search tree should be perfectly balanced. Previous work has shown that a dominating factor over the running time for a search is the number of cache faults performed, and that an appropriate memory layout of a binary search tree...... can reduce the number of cache faults by several hundred percent. Motivated by the fact that during a search branching to the left or right at a node does not necessarily have the same cost, e.g. because of branch prediction schemes, we in this paper study the class of skewed binary search trees....... For all nodes in a skewed binary search tree the ratio between the size of the left subtree and the size of the tree is a fixed constant (a ratio of 1/2 gives perfect balanced trees). In this paper we present an experimental study of various memory layouts of static skewed binary search trees, where each...

  18. Binary Neutron Star Mergers.

    Science.gov (United States)

    Faber, Joshua A; Rasio, Frederic A

    2012-01-01

    We review the current status of studies of the coalescence of binary neutron star systems. We begin with a discussion of the formation channels of merging binaries and we discuss the most recent theoretical predictions for merger rates. Next, we turn to the quasi-equilibrium formalisms that are used to study binaries prior to the merger phase and to generate initial data for fully dynamical simulations. The quasi-equilibrium approximation has played a key role in developing our understanding of the physics of binary coalescence and, in particular, of the orbital instability processes that can drive binaries to merger at the end of their lifetimes. We then turn to the numerical techniques used in dynamical simulations, including relativistic formalisms, (magneto-)hydrodynamics, gravitational-wave extraction techniques, and nuclear microphysics treatments. This is followed by a summary of the simulations performed across the field to date, including the most recent results from both fully relativistic and microphysically detailed simulations. Finally, we discuss the likely directions for the field as we transition from the first to the second generation of gravitational-wave interferometers and while supercomputers reach the petascale frontier.

  19. Binary Neutron Star Mergers

    Directory of Open Access Journals (Sweden)

    Joshua A. Faber

    2012-07-01

    Full Text Available We review the current status of studies of the coalescence of binary neutron star systems. We begin with a discussion of the formation channels of merging binaries and we discuss the most recent theoretical predictions for merger rates. Next, we turn to the quasi-equilibrium formalisms that are used to study binaries prior to the merger phase and to generate initial data for fully dynamical simulations. The quasi-equilibrium approximation has played a key role in developing our understanding of the physics of binary coalescence and, in particular, of the orbital instability processes that can drive binaries to merger at the end of their lifetimes. We then turn to the numerical techniques used in dynamical simulations, including relativistic formalisms, (magneto-hydrodynamics, gravitational-wave extraction techniques, and nuclear microphysics treatments. This is followed by a summary of the simulations performed across the field to date, including the most recent results from both fully relativistic and microphysically detailed simulations. Finally, we discuss the likely directions for the field as we transition from the first to the second generation of gravitational-wave interferometers and while supercomputers reach the petascale frontier.

  20. Binary and Millisecond Pulsars.

    Science.gov (United States)

    Lorimer, Duncan R

    2008-01-01

    We review the main properties, demographics and applications of binary and millisecond radio pulsars. Our knowledge of these exciting objects has greatly increased in recent years, mainly due to successful surveys which have brought the known pulsar population to over 1800. There are now 83 binary and millisecond pulsars associated with the disk of our Galaxy, and a further 140 pulsars in 26 of the Galactic globular clusters. Recent highlights include the discovery of the young relativistic binary system PSR J1906+0746, a rejuvination in globular cluster pulsar research including growing numbers of pulsars with masses in excess of 1.5 M⊙, a precise measurement of relativistic spin precession in the double pulsar system and a Galactic millisecond pulsar in an eccentric (e = 0.44) orbit around an unevolved companion. Supplementary material is available for this article at 10.12942/lrr-2008-8.

  1. Modelling binary data

    CERN Document Server

    Collett, David

    2002-01-01

    INTRODUCTION Some Examples The Scope of this Book Use of Statistical Software STATISTICAL INFERENCE FOR BINARY DATA The Binomial Distribution Inference about the Success Probability Comparison of Two Proportions Comparison of Two or More Proportions MODELS FOR BINARY AND BINOMIAL DATA Statistical Modelling Linear Models Methods of Estimation Fitting Linear Models to Binomial Data Models for Binomial Response Data The Linear Logistic Model Fitting the Linear Logistic Model to Binomial Data Goodness of Fit of a Linear Logistic Model Comparing Linear Logistic Models Linear Trend in Proportions Comparing Stimulus-Response Relationships Non-Convergence and Overfitting Some other Goodness of Fit Statistics Strategy for Model Selection Predicting a Binary Response Probability BIOASSAY AND SOME OTHER APPLICATIONS The Tolerance Distribution Estimating an Effective Dose Relative Potency Natural Response Non-Linear Logistic Regression Models Applications of the Complementary Log-Log Model MODEL CHECKING Definition of Re...

  2. Binary and Millisecond Pulsars

    Directory of Open Access Journals (Sweden)

    Lorimer Duncan R.

    2008-11-01

    Full Text Available We review the main properties, demographics and applications of binary and millisecond radio pulsars. Our knowledge of these exciting objects has greatly increased in recent years, mainly due to successful surveys which have brought the known pulsar population to over 1800. There are now 83 binary and millisecond pulsars associated with the disk of our Galaxy, and a further 140 pulsars in 26 of the Galactic globular clusters. Recent highlights include the discovery of the young relativistic binary system PSR J1906+0746, a rejuvination in globular cluster pulsar research including growing numbers of pulsars with masses in excess of 1.5M_⊙, a precise measurement of relativistic spin precession in the double pulsar system and a Galactic millisecond pulsar in an eccentric (e = 0.44 orbit around an unevolved companion.

  3. Field guide to the binary stars

    Energy Technology Data Exchange (ETDEWEB)

    Trimble, V. (Maryland Univ., College Park (USA). Astronomy Program; California Univ., Irvine (USA). Dept. of Physics)

    1983-05-12

    For most of the history of binary star astronomy, systems have been classified largely on the basis of how they were discovered and qualitative appearance of their spectra and light curves. Present understanding of single and double star evolution has now progressed to the point where most of the classes previously identified, and some new ones, can be arranged into evolutionary sequences, depending primarily on the initial masses and separation of the component stars.

  4. Binary and Millisecond Pulsars

    Directory of Open Access Journals (Sweden)

    Duncan R. Lorimer

    1998-09-01

    Full Text Available Our knowledge of binary and millisecond pulsars has greatly increased in recent years. This is largely due to the success of large-area surveys which have brought the known population of such systems in the Galactic disk to around 50. As well as being interesting as a population of astronomical sources, many pulsars turn out to be superb celestial clocks. In this review we summarise the main properties of binary and millisecond pulsars and highlight some of their applications to relativistic astrophysics.

  5. Binary and Millisecond Pulsars

    Directory of Open Access Journals (Sweden)

    Lorimer Duncan R.

    2005-11-01

    Full Text Available We review the main properties, demographics and applications of binary and millisecond radio pulsars. Our knowledge of these exciting objects has greatly increased in recent years, mainly due to successful surveys which have brought the known pulsar population to over 1700. There are now 80 binary and millisecond pulsars associated with the disk of our Galaxy, and a further 103 pulsars in 24 of the Galactic globular clusters. Recent highlights have been the discovery of the first ever double pulsar system and a recent flurry of discoveries in globular clusters, in particular Terzan 5.

  6. On the initial binary population for star cluster simulations

    Science.gov (United States)

    Belloni, Diogo; Askar, Abbas; Giersz, Mirek; Kroupa, Pavel; Rocha-Pinto, Helio J.

    2017-11-01

    Colour-magnitude diagrams (CMDs) are powerful tools that might be used to infer stellar properties in globular clusters (GCs), for example, the binary fraction and their mass ratio (q) distribution. In the past few years, observations have revealed that q distributions of GC main-sequence binaries are generally flat, and a distribution characterized by a strong increase towards q ≈ 1 is not typical in GCs. In numerical simulations of GC evolution with the initial binary population (IBP) described by Kroupa, synthetic CMD colour distributions exhibit a peak associated with binaries that have q ≈ 1. While the Kroupa IBP reproduces binary properties in star-forming regions, clusters and the Galactic field, the peak in the q distribution towards q ≈ 1 observed for GC simulations is not consistent with distributions derived from observations. The objective of this paper is to refine and further improve the physical formulation of pre-main-sequence eigenevolution proposed by Kroupa in order to achieve CMD colour distributions of simulated GC models similar to those observed in real GCs, and to get a similarly good agreement with binary properties for late-type binaries in the Galactic field. We present in this paper a modified Kroupa IBP, in which early-type stars follow observational distributions, and late-type stars are generated according to slightly modified pre-main-sequence eigenevolution prescriptions. Our modifications not only lead to a qualitatively good agreement with respect to long-term observations of late-type binaries in the Galactic field but also resolve the above-mentioned problem related to binary distributions in GC models.

  7. Orbital Decay in Binaries with Evolved Stars

    Science.gov (United States)

    Sun, Meng; Arras, Phil; Weinberg, Nevin N.; Troup, Nicholas; Majewski, Steven R.

    2018-01-01

    Two mechanisms are often invoked to explain tidal friction in binary systems. The ``dynamical tide” is the resonant excitation of internal gravity waves by the tide, and their subsequent damping by nonlinear fluid processes or thermal diffusion. The ``equilibrium tide” refers to non-resonant excitation of fluid motion in the star’s convection zone, with damping by interaction with the turbulent eddies. There have been numerous studies of these processes in main sequence stars, but less so on the subgiant and red giant branches. Motivated by the newly discovered close binary systems in the Apache Point Observatory Galactic Evolution Experiment (APOGEE-1), we have performed calculations of both the dynamical and equilibrium tide processes for stars over a range of mass as the star’s cease core hydrogen burning and evolve to shell burning. Even for stars which had a radiative core on the main sequence, the dynamical tide may have very large amplitude in the newly radiative core in post-main sequence, giving rise to wave breaking. The resulting large dynamical tide dissipation rate is compared to the equilibrium tide, and the range of secondary masses and orbital periods over which rapid orbital decay may occur will be discussed, as well as applications to close APOGEE binaries.

  8. The first light curve analysis of eclipsing binary NR Cam

    Science.gov (United States)

    Tavakkoli, F.; Hasanzadeh, A.; Poro, A.

    2015-05-01

    New observations of the eclipsing binary system NR Cam were carried out using a CCD in B, V, and R filters and new times of light minimum and new ephemeris were obtained. The B, V, and R light curves were analyzed using both the Binary Maker 3.0 and PHOEBE 0.31 programs to determine some geometrical and physical parameters of the system. These results show that NR Cam is an overcontact binary and that both components are Main Sequence stars. The O'Connell effect on NR Cam was studied and some variations in spot parameters were obtained over the different years.

  9. Equational binary decision diagrams

    NARCIS (Netherlands)

    J.F. Groote (Jan Friso); J.C. van de Pol (Jaco)

    2000-01-01

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

  10. Binary tense and modality

    NARCIS (Netherlands)

    Broekhuis, H.; Verkuyl, H.J

    2014-01-01

    The present paper adopts as its point of departure the claim by Te Winkel (1866) and Verkuyl (2008) that mental temporal representations are built on the basis of three binary oppositions: Present/Past, Synchronous/Posterior and Imperfect/Perfect. Te Winkel took the second opposition in terms of the

  11. Cost-effectiveness of multidisciplinary wound care in nursing homes: a pseudo-randomized pragmatic cluster trial.

    Science.gov (United States)

    Vu, Trang; Harris, Anthony; Duncan, Gregg; Sussman, Geoff

    2007-09-01

    To evaluate the cost-effectiveness of a multidisciplinary wound care team in the nursing home setting from a health system perspective. Pseudo-randomized pragmatic cluster trial with 20-week follow-up involving 342 uncomplicated leg and pressure ulcers in 176 residents located in 44 high-care nursing homes in Melbourne, Australia in 1999-2000. Twenty-one nursing homes (180 wounds in 94 residents) were assigned to the intervention arm and 23 to the control arm (162 wounds in 82 residents). Residents in the intervention arm received standardized treatment from a wound care team comprising of trained community pharmacists and nurses. Residents in the control arm received usual care. More wounds healed during the trial in the intervention arm than in the control arm (61.7% versus 52.5%, P = 0.07). A Cox regression with shared frailty predicted that the chances of healing increased 73% for intervention wounds [95% confidence interval (CI) 20-150%, P = 0.003]. The mean treatment cost was $A616.4 for intervention and $A977.9 for control patients (P = 0.006). Most cost reduction was obtained from decreases in nursing time and waste disposal. The mean cost saving per wound, adjusted for baseline wound severity and random censoring, was $A277.9 (95% CI $A21.6-$A534.1). Standardized treatment provided by a multidisciplinary wound care team saved costs and improved chronic wound healing in nursing homes. The main source of saving was in the cost of nursing time in applying traditional dressings and in the cost of their disposal.

  12. Black holes in binary stars

    NARCIS (Netherlands)

    Wijers, R.A.M.J.

    1996-01-01

    Introduction Distinguishing neutron stars and black holes Optical companions and dynamical masses X-ray signatures of the nature of a compact object Structure and evolution of black-hole binaries High-mass black-hole binaries Low-mass black-hole binaries Low-mass black holes Formation of black holes

  13. Infalling clouds on to supermassive black hole binaries - II. Binary evolution and the final parsec problem

    Science.gov (United States)

    Goicovic, Felipe G.; Sesana, Alberto; Cuadra, Jorge; Stasyszyn, Federico

    2017-11-01

    The formation of massive black hole binaries (MBHBs) is an unavoidable outcome of galaxy evolution via successive mergers. However, the mechanism that drives their orbital evolution from parsec separations down to the gravitational wave dominated regime is poorly understood, and their final fate is still unclear. If such binaries are embedded in gas-rich and turbulent environments, as observed in remnants of galaxy mergers, the interaction with gas clumps (such as molecular clouds) may efficiently drive their orbital evolution. Using numerical simulations, we test this hypothesis by studying the dynamical evolution of an equal mass, circular MBHB accreting infalling molecular clouds. We investigate different orbital configurations, modelling a total of 13 systems to explore different possible impact parameters and relative inclinations of the cloud-binary encounter. We focus our study on the prompt, transient phase during the first few orbits when the dynamical evolution of the binary is fastest, finding that this evolution is dominated by the exchange of angular momentum through gas capture by the individual black holes and accretion. Building on these results, we construct a simple model for evolving an MBHB interacting with a sequence of clouds, which are randomly drawn from reasonable populations with different levels of anisotropy in their angular momenta distributions. We show that the binary efficiently evolves down to the gravitational wave emission regime within a few hundred million years, overcoming the `final parsec' problem regardless of the stellar distribution.

  14. Comparison of tool feed influence in CNC polishing between a novel circular-random path and other pseudo-random paths.

    Science.gov (United States)

    Takizawa, Ken; Beaucamp, Anthony

    2017-09-18

    A new category of circular pseudo-random paths is proposed in order to suppress repetitive patterns and improve surface waviness on ultra-precision polished surfaces. Random paths in prior research had many corners, therefore deceleration of the polishing tool affected the surface waviness. The new random path can suppress velocity changes of the polishing tool and thus restrict degradation of the surface waviness, making it suitable for applications with stringent mid-spatial-frequency requirements such as photomask blanks for EUV lithography.

  15. Young and Waltzing Binary Stars

    Science.gov (United States)

    2001-10-01

    binary system and the third object that shines with constant light. Both the primary, deeper and the secondary, less deep eclipses are well visible. The primary eclipse was observed on December 8, 2000 and is here displayed at phase zero. During this minimum, the brightness of the binary system decreases by about 45% (0.4 magnitudes). The primary eclipse takes place when the smaller component blocks the light from the brighter and hotter star. The orbital motions of the two stars are illustrated by a computer-generated, animated sequence. The secondary eclipse (at phase 0.5) dims the light from the system less; it occurs when the larger and brighter star almost completely (about 90%) hides its smaller companion. The second minimum was recorded on January 12, 2001. None of the eclipses is therefore "total". The stellar parameters A detailed analysis of these high-precision light curves allowed the astronomers to determine the orbits and hence, to perform an extremely accurate measurement of the fundamental stellar parameters for the two young stars of RXJ 0529.4+0041 . The star that is eclipsed during the primary eclipse (the "primary") is the more massive and also the hotter and brighter of the two stars. Its mass is 1.3 times that of our Sun, i.e., about 2.6 10 30 kg [2]. Its diameter is nearly 1.6 times larger than that of our Sun (i.e., about 2.2 million km) and the surface temperature is found to be a little more than 5000 °C, or a few hundred degrees cooler than the Sun. The "secondary" star is slightly lighter than our Sun. Its weight is about 90% of that of the Sun (1.8 10 30 kg) and the diameter is 20% larger (about 1.7 million km), while the surface temperature is 4000 degrees. In fact, these two stars are still so young that most of their energy comes from the contraction process - the first phase during which they are formed from an interstellar cloud by this process is not yet over and they are still getting smaller. It is by this process that collapsing

  16. Compressing Binary Decision Diagrams

    DEFF Research Database (Denmark)

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

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

  17. Compressing Binary Decision Diagrams

    DEFF Research Database (Denmark)

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

    2008-01-01

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

  18. Binary Masking & Speech Intelligibility

    OpenAIRE

    Boldt, Jesper

    2010-01-01

    The purpose of this thesis is to examine how binary masking can be used to increase intelligibility in situations where hearing impaired listeners have difficulties understanding what is being said. The major part of the experiments carried out in this thesis can be categorized as either experiments under ideal conditions or as experiments under more realistic conditions useful for real-life applications such as hearing aids. In the experiments under ideal conditions, the previously defined i...

  19. Massive Black Hole Binary Evolution

    Directory of Open Access Journals (Sweden)

    Merritt David

    2005-11-01

    Full Text Available Coalescence of binary supermassive black holes (SBHs would constitute the strongest sources of gravitational waves to be observed by LISA. While the formation of binary SBHs during galaxy mergers is almost inevitable, coalescence requires that the separation between binary components first drop by a few orders of magnitude, due presumably to interaction of the binary with stars and gas in a galactic nucleus. This article reviews the observational evidence for binary SBHs and discusses how they would evolve. No completely convincing case of a bound, binary SBH has yet been found, although a handful of systems (e.g. interacting galaxies; remnants of galaxy mergers are now believed to contain two SBHs at projected separations of <~ 1kpc. N-body studies of binary evolution in gas-free galaxies have reached large enough particle numbers to reproduce the slow, “diffusive” refilling of the binary’s loss cone that is believed to characterize binary evolution in real galactic nuclei. While some of the results of these simulations - e.g. the binary hardening rate and eccentricity evolution - are strongly N-dependent, others - e.g. the “damage” inflicted by the binary on the nucleus - are not. Luminous early-type galaxies often exhibit depleted cores with masses of ~ 1-2 times the mass of their nuclear SBHs, consistent with the predictions of the binary model. Studies of the interaction of massive binaries with gas are still in their infancy, although much progress is expected in the near future. Binary coalescence has a large influence on the spins of SBHs, even for mass ratios as extreme as 10:1, and evidence of spin-flips may have been observed.

  20. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry combined with multidimensional scaling, binary hierarchical cluster tree and selected diagnostic masses improves species identification of Neolithic keratin sequences from furs of the Tyrolean Iceman Oetzi.

    Science.gov (United States)

    Hollemeyer, Klaus; Altmeyer, Wolfgang; Heinzle, Elmar; Pitra, Christian

    2012-08-30

    The identification of fur origins from the 5300-year-old Tyrolean Iceman's accoutrement is not yet complete, although definite identification is essential for the socio-cultural context of his epoch. Neither have all potential samples been identified so far, nor there has a consensus been reached on the species identified using the classical methods. Archaeological hair often lacks analyzable hair scale patterns in microscopic analyses and polymer chain reaction (PCR)-based techniques are often inapplicable due to the lack of amplifiable ancient DNA. To overcome these drawbacks, a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) method was used exclusively based on hair keratins. Thirteen fur specimens from his accoutrement were analyzed after tryptic digest of native hair. Peptide mass fingerprints (pmfs) from ancient samples and from reference species mostly occurring in the Alpine surroundings at his lifetime were compared to each other using multidimensional scaling and binary hierarchical cluster tree analysis. Both statistical methods highly reflect spectral similarities among pmfs as close zoological relationships. While multidimensional scaling was useful to discriminate specimens on the zoological order level, binary hierarchical cluster tree reached the family or subfamily level. Additionally, the presence and/or absence of order, family and/or species-specific diagnostic masses in their pmfs allowed the identification of mammals mostly down to single species level. Red deer was found in his shoe vamp, goat in the leggings, cattle in his shoe sole and at his quiver's closing flap as well as sheep and chamois in his coat. Canid species, like grey wolf, domestic dog or European red fox, were discovered in his leggings for the first time, but could not be differentiated to species level. This is widening the spectrum of processed fur-bearing species to at least one member of the Canidae family. His fur cap was

  1. Expanding Pseudorandom Functions

    DEFF Research Database (Denmark)

    Damgård, Ivan Bjerre; Nielsen, Jesper Buus

    2002-01-01

    used) encryption modes as CBC mode and counter (CTR) mode, but is provably secure against chosen-plaintext attack (CPA) already if the underlying symmetric cipher is secure against known-plaintext attack (KPA). We prove that CBC, CTR and Jutla’s integrity aware modes do not have this property....... In particular, we prove that when using a KPA secure block cipher, then: CBC mode is KPA secure, but need not be CPA secure, Jutla’s modes need not be CPA secure, and CTR mode need not be even KPA secure. The analysis is done in a concrete security framework....

  2. Particle acceleration in binaries

    Directory of Open Access Journals (Sweden)

    Sinitsyna V.G.

    2017-01-01

    Full Text Available Cygnus X-3 massive binary system is one of the powerful sources of radio and X-ray emission consisting of an accreting compact object, probably a black hole, with a Wolf-Rayet star companion. Based on the detections of ultra high energy gamma-rays by Kiel and Havera Park, Cygnus X-3 has been proposed to be one of the most powerful sources of charged cosmic ray particles in the Galaxy. The results of long-term observations of the Cyg X-3 binary at energies 800 GeV–85 TeV detected by SHALON in 1995 are presented with images, integral spectra and spectral energy distribution. The identification of source with Cygnus X-3 detected by SHALON was secured by the detection of its 4.8 hour orbital period in TeV gamma-rays. During the whole observation period of Cyg X-3 with SHALON significant flux increases were detected at energies above 0.8 TeV. These TeV flux increases are correlated with flaring activity at a lower energy range of X-ray and/or at observations of Fermi LAT as well as with radio emission from the relativistic jets of Cygnus X-3. The variability of very high-energy gamma-radiation and correlation of radiation activity in the wide energy range can provide essential information on particle mechanism production up to very high energies. Whereas, modulation of very high energy emission connected to the orbital motion of the binary system, provides an understanding of the emission processes, nature and location of particle acceleration.

  3. Particle acceleration in binaries

    Science.gov (United States)

    Sinitsyna, V. G.; Sinitsyna, V. Y.

    2017-06-01

    Cygnus X-3 massive binary system is one of the powerful sources of radio and X-ray emission consisting of an accreting compact object, probably a black hole, with a Wolf-Rayet star companion. Based on the detections of ultra high energy gamma-rays by Kiel and Havera Park, Cygnus X-3 has been proposed to be one of the most powerful sources of charged cosmic ray particles in the Galaxy. The results of long-term observations of the Cyg X-3 binary at energies 800 GeV-85 TeV detected by SHALON in 1995 are presented with images, integral spectra and spectral energy distribution. The identification of source with Cygnus X-3 detected by SHALON was secured by the detection of its 4.8 hour orbital period in TeV gamma-rays. During the whole observation period of Cyg X-3 with SHALON significant flux increases were detected at energies above 0.8 TeV. These TeV flux increases are correlated with flaring activity at a lower energy range of X-ray and/or at observations of Fermi LAT as well as with radio emission from the relativistic jets of Cygnus X-3. The variability of very high-energy gamma-radiation and correlation of radiation activity in the wide energy range can provide essential information on particle mechanism production up to very high energies. Whereas, modulation of very high energy emission connected to the orbital motion of the binary system, provides an understanding of the emission processes, nature and location of particle acceleration.

  4. An Eccentric Binary Millisecond Pulsar in the Galactic Plane

    Science.gov (United States)

    Champion, David J.; Ransom, Scott M.; Lazarus, Patrick; Camilo, Fernando; Bassa, Cess; Kaspi, Victoria M.; Nice, David J.; Freire, Paulo C. C.; Stairs, Ingrid H.; vanLeeuwen, Joeri; hide

    2008-01-01

    Binary pulsar systems are superb probes of stellar and binary evolution and the physics of extreme environments. In a survey with the Arecibo telescope, we have found PSR J1903+0327, a radio pulsar with a rotational period of 2.15 milliseconds in a highly eccentric (e = 0.44) 95-day orbit around a solar mass (M.) companion. Infrared observations identify a possible main-sequence companion star. Conventional binary stellar evolution models predict neither large orbital eccentricities nor main-sequence companions around millisecond pulsars. Alternative formation scenarios involve recycling a neutron star in a globular cluster, then ejecting it into the Galactic disk, or membership in a hierarchical triple system. A relativistic analysis of timing observations of the pulsar finds its mass to be 1.74 +/- 0.04 Solar Mass, an unusually high value.

  5. An eccentric binary millisecond pulsar in the galactic plane.

    Science.gov (United States)

    Champion, David J; Ransom, Scott M; Lazarus, Patrick; Camilo, Fernando; Bassa, Cees; Kaspi, Victoria M; Nice, David J; Freire, Paulo C C; Stairs, Ingrid H; van Leeuwen, Joeri; Stappers, Ben W; Cordes, James M; Hessels, Jason W T; Lorimer, Duncan R; Arzoumanian, Zaven; Backer, Don C; Bhat, N D Ramesh; Chatterjee, Shami; Cognard, Ismaël; Deneva, Julia S; Faucher-Giguère, Claude-André; Gaensler, Bryan M; Han, Jinlin; Jenet, Fredrick A; Kasian, Laura; Kondratiev, Vlad I; Kramer, Michael; Lazio, Joseph; McLaughlin, Maura A; Venkataraman, Arun; Vlemmings, Wouter

    2008-06-06

    Binary pulsar systems are superb probes of stellar and binary evolution and the physics of extreme environments. In a survey with the Arecibo telescope, we have found PSR J1903+0327, a radio pulsar with a rotational period of 2.15 milliseconds in a highly eccentric (e = 0.44) 95-day orbit around a solar mass (M(middle dot in circle)) companion. Infrared observations identify a possible main-sequence companion star. Conventional binary stellar evolution models predict neither large orbital eccentricities nor main-sequence companions around millisecond pulsars. Alternative formation scenarios involve recycling a neutron star in a globular cluster, then ejecting it into the Galactic disk, or membership in a hierarchical triple system. A relativistic analysis of timing observations of the pulsar finds its mass to be 1.74 +/- 0.04 M solar symbol, an unusually high value.

  6. Magnetic binary nanofillers

    Energy Technology Data Exchange (ETDEWEB)

    Morales Mendoza, N. [INQUIMAE, CONICET-UBA, Ciudad Universitaria, Pab2, (C1428EHA) Bs As (Argentina); LPyMC, Dep. De Fisica, FCEN-UBA and IFIBA -CONICET, Ciudad Universitaria, Cap. Fed. (Argentina); Goyanes, S. [LPyMC, Dep. De Fisica, FCEN-UBA and IFIBA -CONICET, Ciudad Universitaria, Cap. Fed. (Argentina); Chiliotte, C.; Bekeris, V. [LBT, Dep. De Fisica, FCEN-UBA. Ciudad Universitaria, Pab1, C1428EGA CABA (Argentina); Rubiolo, G. [LPyMC, Dep. De Fisica, FCEN-UBA and IFIBA -CONICET, Ciudad Universitaria, Cap. Fed. (Argentina); Unidad de Actividad Materiales, CNEA, Av Gral. Paz 1499, San Martin (1650), Prov. de Bs As (Argentina); Candal, R., E-mail: candal@qi.fcen.uba.ar [INQUIMAE, CONICET-UBA, Ciudad Universitaria, Pab2, (C1428EHA) Bs As (Argentina); Escuela de Ciencia y Tecnologia, 3iA, Universidad de Gral. San Martin, San Martin, Prov. Bs As (Argentina)

    2012-08-15

    Magnetic binary nanofillers containing multiwall carbon nanotubes (MWCNT) and hercynite were synthesized by Chemical Vapor Deposition (CVD) on Fe/AlOOH prepared by the sol-gel method. The catalyst precursor was fired at 450 Degree-Sign C, ground and sifted through different meshes. Two powders were obtained with different particle sizes: sample A (50-75 {mu}m) and sample B (smaller than 50 {mu}m). These powders are composed of iron oxide particles widely dispersed in the non-crystalline matrix of aluminum oxide and they are not ferromagnetic. After reduction process the powders are composed of {alpha}-Fe nanoparticles inside hercynite matrix. These nanofillers are composed of hercynite containing {alpha}-Fe nanoparticles and MWCNT. The binary magnetic nanofillers were slightly ferromagnetic. The saturation magnetization of the nanofillers depended on the powder particle size. The nanofiller obtained from powder particles in the range 50-75 {mu}m showed a saturation magnetization 36% higher than the one formed from powder particles smaller than 50 {mu}m. The phenomenon is explained in terms of changes in the magnetic environment of the particles as consequence of the presence of MWCNT.

  7. Binary Trees and Parallel Scheduling Algorithms.

    Science.gov (United States)

    1980-09-01

    child of N) and t (N)- t (right child of N) . For bur example, the binary comutation tree together with time intervals is shown in Figure 2.2. A...Operationafle, 10.5, Supp.7-33, 1976. 22. Lenstra, J. K., "Sequencing by enumerative methods," Mathematical Centre Tract 69, Mathematisch Centrum, Amsterdam...Theory of Scheduling and its applications, Lecture Notes -Tn Economics and Mathematical Systems, 86 -34- Springer, Berlin, pp. 393-398, i973. 35. Smith, W

  8. Formation and Evolution of X-ray Binaries

    Science.gov (United States)

    Shao, Y.

    2017-07-01

    X-ray binaries are a class of binary systems, in which the accretor is a compact star (i.e., black hole, neutron star, or white dwarf). They are one of the most important objects in the universe, which can be used to study not only binary evolution but also accretion disks and compact stars. Statistical investigations of these binaries help to understand the formation and evolution of galaxies, and sometimes provide useful constraints on the cosmological models. The goal of this thesis is to investigate the formation and evolution processes of X-ray binaries including Be/X-ray binaries, low-mass X-ray binaries (LMXBs), ultraluminous X-ray sources (ULXs), and cataclysmic variables. In Chapter 1 we give a brief review on the basic knowledge of the binary evolution. In Chapter 2 we discuss the formation of Be stars through binary interaction. In this chapter we investigate the formation of Be stars resulting from mass transfer in binaries in the Galaxy. Using binary evolution and population synthesis calculations, we find that in Be/neutron star binaries the Be stars have a lower limit of mass ˜ 8 M⊙ if they are formed by a stable (i.e., without the occurrence of common envelope evolution) and nonconservative mass transfer. We demonstrate that the isolated Be stars may originate from both mergers of two main-sequence stars and disrupted Be binaries during the supernova explosions of the primary stars, but mergers seem to play a much more important role. Finally the fraction of Be stars produced by binary interactions in all B type stars can be as high as ˜ 13%-30% , implying that most of Be stars may result from binary interaction. In Chapter 3 we show the evolution of intermediate- and low-mass X-ray binaries (I/LMXBs) and the formation of millisecond pulsars. Comparing the calculated results with the observations of binary radio pulsars, we report the following results: (1) The allowed parameter space for forming binary pulsars in the initial orbital period

  9. Construction and characterization of a partial binary bacterial ...

    African Journals Online (AJOL)

    Construction and characterization of a partial binary bacterial artificial chromosome (BIBAC) of Agave tequilana var. azul (2X) and its application for gene identification. ... Our results indicate that the obtained genomic library is suitable for the identification of sequences of interest, for genetic mapping and for studies of gene ...

  10. Optimally cloned binary coherent states

    DEFF Research Database (Denmark)

    Mueller, C. R.; Leuchs, G.; Marquardt, Ch

    2017-01-01

    Binary coherent state alphabets can be represented in a two-dimensional Hilbert space. We capitalize this formal connection between the otherwise distinct domains of qubits and continuous variable states to map binary phase-shift keyed coherent states onto the Bloch sphere and to derive...

  11. Relativistic Binaries in Globular Clusters

    Directory of Open Access Journals (Sweden)

    Benacquista Matthew J.

    2006-02-01

    Full Text Available The galactic population of globular clusters are old, dense star systems, with a typical cluster containing 10^4 - 10^7 stars. As an old population of stars, globular clusters contain many collapsed and degenerate objects. As a dense population of stars, globular clusters are the scene of many interesting close dynamical interactions between stars. These dynamical interactions can alter the evolution of individual stars and can produce tight binary systems containing one or two compact objects. In this review, we discuss the theoretical models of globular cluster evolution and binary evolution, techniques for simulating this evolution which lead to relativistic binaries, and current and possible future observational evidence for this population. Globular cluster evolution will focus on the properties that boost the production of hard binary systems and on the tidal interactions of the galaxy with the cluster, which tend to alter the structure of the globular cluster with time. The interaction of the components of hard binary systems alters the evolution of both bodies and can lead to exotic objects. Direct N-body integrations and Fokker-Planck simulations of the evolution of globular clusters that incorporate tidal interactions and lead to predictions of relativistic binary populations are also discussed. We discuss the current observational evidence for cataclysmic variables, millisecond pulsars, and low-mass X-ray binaries as well as possible future detection of relativistic binaries with gravitational radiation.

  12. Relativistic Binaries in Globular Clusters

    Directory of Open Access Journals (Sweden)

    Benacquista Matthew

    2002-01-01

    Full Text Available The galactic population of globular clusters are old, dense star systems, with a typical cluster containing $10^4 - 10^6$ stars. As an old population of stars, globular clusters contain many collapsed and degenerate objects. As a dense population of stars, globular clusters are the scene of many interesting close dynamical interactions between stars. These dynamical interactions can alter the evolution of individual stars and can produce tight binary systems containing one or two compact objects. In this review, we discuss the theoretical models of globular cluster evolution and binary evolution, techniques for simulating this evolution which lead to relativistic binaries, and current and possible future observational evidence for this population. Globular cluster evolution will focus on the properties that boost the production of hard binary systems and on the tidal interactions of the galaxy with the cluster, which tend to alter the structure of the globular cluster with time. The interaction of the components of hard binary systems alters the evolution of both bodies and can lead to exotic objects. Direct $N$-body integrations and Fokker--Planck simulations of the evolution of globular clusters that incorporate tidal interactions and lead to predictions of relativistic binary populations are also discussed. We discuss the current observational evidence for cataclysmic variables, millisecond pulsars, and low-mass X-ray binaries as well as possible future detection of relativistic binaries with gravitational radiation.

  13. Relativistic Binaries in Globular Clusters

    Directory of Open Access Journals (Sweden)

    Matthew J. Benacquista

    2013-03-01

    Full Text Available Galactic globular clusters are old, dense star systems typically containing 10^4 – 10^6 stars. As an old population of stars, globular clusters contain many collapsed and degenerate objects. As a dense population of stars, globular clusters are the scene of many interesting close dynamical interactions between stars. These dynamical interactions can alter the evolution of individual stars and can produce tight binary systems containing one or two compact objects. In this review, we discuss theoretical models of globular cluster evolution and binary evolution, techniques for simulating this evolution that leads to relativistic binaries, and current and possible future observational evidence for this population. Our discussion of globular cluster evolution will focus on the processes that boost the production of tight binary systems and the subsequent interaction of these binaries that can alter the properties of both bodies and can lead to exotic objects. Direct N-body integrations and Fokker–Planck simulations of the evolution of globular clusters that incorporate tidal interactions and lead to predictions of relativistic binary populations are also discussed. We discuss the current observational evidence for cataclysmic variables, millisecond pulsars, and low-mass X-ray binaries as well as possible future detection of relativistic binaries with gravitational radiation.

  14. A mini binary vector series for plant transformation.

    Science.gov (United States)

    Xiang, C; Han, P; Lutziger, I; Wang, K; Oliver, D J

    1999-07-01

    A streamlined mini binary vector was constructed that is less than 1/2 the size of the pBIN19 backbone (3.5 kb). This was accomplished by eliminating over 5 kb of non-T-DNA sequences from the pBIN19 vector. The vector still retains all the essential elements required for a binary vector. These include a RK2 replication origin, the nptIII gene conferring kanamycin resistance in bacteria, both the right and left T-DNA borders, and a multiple cloning site (MCS) in between the T-DNA borders to facilitate cloning. Due to the reduced size, more unique restriction sites are available in the MCS, thus allowing more versatile cloning. Since the traF region was not included, it is not possible to mobilize this binary vector into Agrobacterium by triparental mating. This problem can be easily resolved by direct transformation. The mini binary vector has been demonstrated to successfully transform Arabidopsis plants. Based on this mini binary vector, a series of binary vectors were constructed for plant transformation.

  15. Signature Visualization of Software Binaries

    Energy Technology Data Exchange (ETDEWEB)

    Panas, T

    2008-07-01

    In this paper we present work on the visualization of software binaries. In particular, we utilize ROSE, an open source compiler infrastructure, to pre-process software binaries, and we apply a landscape metaphor to visualize the signature of each binary (malware). We define the signature of a binary as a metric-based layout of the functions contained in the binary. In our initial experiment, we visualize the signatures of a series of computer worms that all originate from the same line. These visualizations are useful for a number of reasons. First, the images reveal how the archetype has evolved over a series of versions of one worm. Second, one can see the distinct changes between version. This allows the viewer to form conclusions about the development cycle of a particular worm.

  16. Planets in Binary Star Systems

    CERN Document Server

    Haghighipour, Nader

    2010-01-01

    The discovery of extrasolar planets over the past decade has had major impacts on our understanding of the formation and dynamical evolution of planetary systems. There are features and characteristics unseen in our solar system and unexplainable by the current theories of planet formation and dynamics. Among these new surprises is the discovery of planets in binary and multiple-star systems. The discovery of such "binary-planetary" systems has confronted astrodynamicists with many new challenges, and has led them to re-examine the theories of planet formation and dynamics. Among these challenges are: How are planets formed in binary star systems? What would be the notion of habitability in such systems? Under what conditions can binary star systems have habitable planets? How will volatiles necessary for life appear on such planets? This volume seeks to gather the current research in the area of planets in binary and multistar systems and to familiarize readers with its associated theoretical and observation...

  17. Features of the propagation of pseudorandom pulse signals from the shelf to deep water in the presence of gyre formation on the acoustic track

    Science.gov (United States)

    Akulichev, V. A.; Burenin, A. V.; Ladychenko, S. Yu.; Lobanov, V. B.; Morgunov, Yu. N.

    2017-08-01

    The paper discusses the results of an experiment conducted in the Sea of Japan in March 2016 on an acoustic track 194 km long in winter hydrological conditions. The most complex case of propagation of pseudorandom pulse signals from the shelf to deep water in the presence of gyre formation on the acoustic track. An analysis of the experimentally obtained pulse characteristics show that at all points, a maximum, in terms of amplitude, first arrival of acoustic energy is recorded. This is evidence that at a given depth horizon, pulses that have passed the shortest distance through a near-surface sound channel at small angles close to zero are received first. The calculation method of mean sound velocity on the track, based on the satellite data of surface temperature monitoring, is proposed. We expect that the results obtained with this method can be successfully used for the purposes of acoustic range finding and navigation.

  18. Irradiation and mass transfer in low-mass compact binaries

    OpenAIRE

    Ritter, H.; Kolb, U.; Zhang, Z. -Y.

    2000-01-01

    We study the reaction of low-mass stars to anisotropic irradiation and its importance for the long-term evolution of compact binaries binaries. We show by means of a simple homology model that if the energy outflow through the surface layers of a low-mass main sequence star is blocked over a fraction s_eff < 1 of its surface it will inflate only modestly and that the maximum contribution to mass transfer is s_eff times what one obtains in the isotropic case. The duration of this mass transfer...

  19. Optimally cloned binary coherent states

    Science.gov (United States)

    Müller, C. R.; Leuchs, G.; Marquardt, Ch.; Andersen, U. L.

    2017-10-01

    Binary coherent state alphabets can be represented in a two-dimensional Hilbert space. We capitalize this formal connection between the otherwise distinct domains of qubits and continuous variable states to map binary phase-shift keyed coherent states onto the Bloch sphere and to derive their quantum-optimal clones. We analyze the Wigner function and the cumulants of the clones, and we conclude that optimal cloning of binary coherent states requires a nonlinearity above second order. We propose several practical and near-optimal cloning schemes and compare their cloning fidelity to the optimal cloner.

  20. Binary Population and Spectral Synthesis

    Science.gov (United States)

    Eldridge, J. J.; Stanway, E. R.; Xiao, L.; McClelland, L. A. S.; Bray, J. C.; Taylor, G.; Ng, M.

    2017-11-01

    We have recently released version 2.0 of the Binary Population and Spectral Synthesis (BPASS) population synthesis code. This is designed to construct the spectra and related properties of stellar populations built from ~200,000 detailed, individual stellar models of known age and metallicity. The output products enable a broad range of theoretical predictions for individual stars, binaries, resolved and unresolved stellar populations, supernovae and their progenitors, and compact remnant mergers. Here we summarise key applications that demonstrate that binary populations typically reproduce observations better than single star models.

  1. Reliable communication over non-binary insertion/deletion channels

    CERN Document Server

    Yazdani, Raman

    2012-01-01

    We consider the problem of reliable communication over non-binary insertion/deletion channels where symbols are randomly deleted from or inserted in the transmitted sequence and all symbols are corrupted by additive white Gaussian noise. To this end, we utilize the inherent redundancy achievable in non-binary symbol sets by first expanding the symbol set and then allocating part of the bits associated with each symbol to watermark symbols. The watermark sequence, known at the receiver, is then used by a forward-backward algorithm to provide soft information for an outer code which decodes the transmitted sequence. Through numerical results and discussions, we evaluate the performance of the proposed solution and show that it leads to significant system ability to detect and correct insertions/deletions. We also provide estimates of the maximum achievable information rates of the system, compare them with the available bounds, and construct practical codes capable of approaching these limits.

  2. The True Ultracool Binary Fraction Using Spectral Binaries

    Science.gov (United States)

    Bardalez Gagliuffi, Daniella; Burgasser, Adam J.; Schmidt, Sarah J.; Gagné, Jonathan; Faherty, Jacqueline K.; Cruz, Kelle; Gelino, Chris

    2018-01-01

    Brown dwarfs bridge the gap between stars and giant planets. While the essential mechanisms governing their formation are not well constrained, binary statistics are a direct outcome of the formation process, and thus provide a means to test formation theories. Observational constraints on the brown dwarf binary fraction place it at 10 ‑ 20%, dominated by imaging studies (85% of systems) with the most common separation at 4 AU. This coincides with the resolution limit of state-of-the-art imaging techniques, suggesting that the binary fraction is underestimated. We have developed a separation-independent method to identify and characterize tightly-separated (simulation based on different assumptions of the mass function, age distribution, evolutionary models and mass ratio distribution. Applying the correction fraction resulting from this method to the observed spectral binary fraction yields a true binary fraction of 27 ± 4%, which is roughly within 1σ of the binary fraction obtained from high resolution imaging studies, radial velocity and astrometric monitoring. This method can be extended to identify giant planet companions to young brown dwarfs.

  3. New Orbits for 18 Binaries

    Science.gov (United States)

    Cvetković, Z.; Pavlović, R.

    2017-12-01

    Orbital elements of 18 visual binaries are computed using the measurements collected in the Fourth Catalog of Interferometric Measurements of Binary Stars; 15 orbits are determined for the first time and three orbits are revised. Eleven of the binaries, denoted as HDS, were discovered during the Hipparcos mission. The remaining binaries were discovered a few years earlier or later than 1991. All studied pairs are close, and all measured separations are less than 0\\buildrel{\\prime\\prime}\\over{.} 46. The shortest orbital period is 10 years and the longest orbital period is 127 years. Dynamical parallaxes and total masses of systems are derived from the orbital elements. We also give absolute magnitudes, spectral types, and (O-C) residuals in θ and ρ.

  4. Mesoscopic model for binary fluids

    Science.gov (United States)

    Echeverria, C.; Tucci, K.; Alvarez-Llamoza, O.; Orozco-Guillén, E. E.; Morales, M.; Cosenza, M. G.

    2017-10-01

    We propose a model for studying binary fluids based on the mesoscopic molecular simulation technique known as multiparticle collision, where the space and state variables are continuous, and time is discrete. We include a repulsion rule to simulate segregation processes that does not require calculation of the interaction forces between particles, so binary fluids can be described on a mesoscopic scale. The model is conceptually simple and computationally efficient; it maintains Galilean invariance and conserves the mass and energy in the system at the micro- and macro-scale, whereas momentum is conserved globally. For a wide range of temperatures and densities, the model yields results in good agreement with the known properties of binary fluids, such as the density profile, interface width, phase separation, and phase growth. We also apply the model to the study of binary fluids in crowded environments with consistent results.

  5. Misclassification in binary choice models

    Czech Academy of Sciences Publication Activity Database

    Meyer, B. D.; Mittag, Nikolas

    2017-01-01

    Roč. 200, č. 2 (2017), s. 295-311 ISSN 0304-4076 Institutional support: RVO:67985998 Keywords : measurement error * binary choice models * program take-up Subject RIV: AH - Economics Impact factor: 1.633, year: 2016

  6. Coalescence of Black Hole-Neutron Star Binaries

    Directory of Open Access Journals (Sweden)

    Masaru Shibata

    2011-08-01

    Full Text Available We review the current status of general relativistic studies for the coalescence of black hole-neutron star (BH-NS binaries. First, procedures for a solution of BH-NS binaries in quasi-equilibrium circular orbits and the numerical results, such as quasi-equilibrium sequence and mass-shedding limit, of the high-precision computation, are summarized. Then, the current status of numerical-relativity simulations for the merger of BH-NS binaries is described. We summarize our understanding for the merger and/or tidal disruption processes, the criterion for tidal disruption, the properties of the remnant formed after the tidal disruption, gravitational waveform, and gravitational-wave spectrum.

  7. Coalescence of Black Hole-Neutron Star Binaries.

    Science.gov (United States)

    Shibata, Masaru; Taniguchi, Keisuke

    2011-01-01

    We review the current status of general relativistic studies for the coalescence of black hole-neutron star (BH-NS) binaries. First, procedures for a solution of BH-NS binaries in quasi-equilibrium circular orbits and the numerical results, such as quasi-equilibrium sequence and mass-shedding limit, of the high-precision computation, are summarized. Then, the current status of numerical-relativity simulations for the merger of BH-NS binaries is described. We summarize our understanding for the merger and/or tidal disruption processes, the criterion for tidal disruption, the properties of the remnant formed after the tidal disruption, gravitational waveform, and gravitational-wave spectrum.

  8. The Binary System Vw-Bootis

    Science.gov (United States)

    Rainger, P. P.; Bell, S. A.; Hilditch, R. W.

    1990-09-01

    Radial velocities for both components of the contact binary system VW Boo are presented for the first time. The orbital analysis is combined with an analysis of Binnendijk's B light curve to yield masses, radii and luminosities for the system. It is shown that the best solution to the light curve is obtained by incorporating a hotspot at the substellar point on the secondary component which is 640+60 K hotter than the surrounding photosphere and is 37±1° in radius. The primary component is a normal main-sequence star, but the secondary is oversized relative to ZAMS stars of the same mass, and hence overluminous. In the HR diagram, the secondary lies mid-way between the secondaries of normal W-type contact binaries (those in true thermal contact), and the increasing number of marginal-contact (or B-type) systems which display EB light curves (those in poor or no thermal contact). Since this is the first such system to be found in such a location, it could suggest that the transition phase from B-type to W-type systems is a short-lived one.

  9. A Stream Encryption Scheme with Both Key and Plaintext Avalanche Effects for Designing Chaos-Based Pseudorandom Number Generator with Application to Image Encryption

    Science.gov (United States)

    Han, Dandan; Min, Lequan; Chen, Guanrong

    Based on a stream encryption scheme with avalanche effect (SESAE), a stream encryption scheme with both key avalanche effect and plaintext avalanche effect (SESKPAE) is introduced. Using this scheme and an ideal 2d-word (d-segment) pseudorandom number generator (PRNG), a plaintext can be encrypted such that each bit of the ciphertext block has a change with the probable probability of (2d - 1)/2d when any word of the key is changed or any bit of the plaintext is changed. To that end, a novel four-dimensional discrete chaotic system (4DDCS) is proposed. Combining the 4DDCS with a generalized synchronization (GS) theorem, a novel eight-dimensional discrete GS chaotic system (8DDGSCS) is constructed. Using the 8DDGSCS, a 216-word chaotic pseudorandom number generator (CPRNG) is designed. The keyspace of the 216-word CPRNG is larger than 21195. Then, the FIPS 140-2 test suit/generalized FIPS 140-2 test suit is used to test the randomness of the 1000-key streams consisting of 20000 bits generated by the 216-word CPRNG, the RC4 algorithm PRNG and the ZUC algorithm PRNG, respectively. The test results show that for the three PRNGs, there are 100%/98.9%, 99.9%/98.8%, 100%/97.9% key streams passing the tests, respectively. Furthermore, the SP800-22 test suite is used to test the randomness of four 100-key streams consisting of 1000000 bits generated by four PRNGs, respectively. The numerical results show that the randomness performances of the 216-word CPRNG is promising, showing that there are no significant correlations between the key streams and the perturbed key streams generated via the 216-word CPRNG. Finally, using the 216-word CPRNG and the SESKPAE to encrypt two gray-scale images, test results demonstrate that the 216-word CPRNG is able to generate both key avalanche effect and plaintext avalanche effect, which are similar to those generated via an ideal CPRNG, and performs better than other comparable schemes.

  10. New Results on Contact Binary Stars

    Science.gov (United States)

    He, J.; Qian, S.; Zhu, L.; Liu, L.; Liao, W.

    2014-08-01

    Contact binary star is a kind of close binary with the strongest interaction binary system. Their formations and evolutions are unsolved problems in astrophysics. Since 2000, our groups have observed and studied more than half a hundred of contact binaries. In this report, I will summarize our new results of some contact binary stars (e.g. UZ CMi, GSC 03526-01995, FU Dra, GSC 0763-0572, V524 Mon, MR Com, etc.). They are as follow: (1) We discovered that V524 Mon and MR Com are shallow-contact binaries with their period decreasing; (2) GSC 03526-01995 is middle-contact binary without a period increasing or decreasing continuously; (3) UZ CMi, GSC 0763-0572 and FU Dra are middle-contact binaries with the period increasing continuously; (4) UZ CMi, GSC 03526-01995, FU Dra and V524 Mon show period oscillation which may imply the presence of additional components in these contact binaries.

  11. Binary neutron stars: Equilibrium models beyond spatial conformal flatness.

    Science.gov (United States)

    Uryū, Kōji; Limousin, François; Friedman, John L; Gourgoulhon, Eric; Shibata, Masaru

    2006-10-27

    Equilibria of binary neutron stars in close circular orbits are computed numerically in a waveless formulation: the full Einstein-relativistic-Euler system is solved on an initial hypersurface to obtain an asymptotically flat form of the 4-metric and an extrinsic curvature whose time derivative vanishes in a comoving frame. Two independent numerical codes are developed, and solution sequences that model inspiraling binary neutron stars during the final several orbits are successfully computed. The binding energy of the system near its final orbit deviates from earlier results of third post-Newtonian and of spatially conformally flat calculations. The new solutions may serve as initial data for merger simulations and as members of quasiequilibrium sequences to generate gravitational-wave templates, and may improve estimates of the gravitational-wave cutoff frequency set by the last inspiral orbit.

  12. Asymmetric distances for binary embeddings.

    Science.gov (United States)

    Gordo, Albert; Perronnin, Florent; Gong, Yunchao; Lazebnik, Svetlana

    2014-01-01

    In large-scale query-by-example retrieval, embedding image signatures in a binary space offers two benefits: data compression and search efficiency. While most embedding algorithms binarize both query and database signatures, it has been noted that this is not strictly a requirement. Indeed, asymmetric schemes that binarize the database signatures but not the query still enjoy the same two benefits but may provide superior accuracy. In this work, we propose two general asymmetric distances that are applicable to a wide variety of embedding techniques including locality sensitive hashing (LSH), locality sensitive binary codes (LSBC), spectral hashing (SH), PCA embedding (PCAE), PCAE with random rotations (PCAE-RR), and PCAE with iterative quantization (PCAE-ITQ). We experiment on four public benchmarks containing up to 1M images and show that the proposed asymmetric distances consistently lead to large improvements over the symmetric Hamming distance for all binary embedding techniques.

  13. Computation and Learning in Neural Networks With Binary Weights

    Science.gov (United States)

    1992-11-28

    exactly once in the Proposition 2.2 If C. is a capacity funcion then so training sequence. is Cn(1-±-o(1)). Conversely, if Cn and C, are any two 2.2...Biswas, Venkatesh 17 ILemma E.1 Lei Ab be a random b x b binary matriz whose components are drawn from a sequcnce of symmetric Bernoulli trials. Then there

  14. Using Binary Code Instrumentation in Computer Security

    Directory of Open Access Journals (Sweden)

    Marius POPA

    2013-01-01

    Full Text Available The paper approaches the low-level details of the code generated by compilers whose format permits outside actions. Binary code modifications are manually done when the internal format is known and understood, or automatically by certain tools developed to process the binary code. The binary code instrumentation goals may be various from security increasing and bug fixing to development of malicious software. The paper highlights the binary code instrumentation techniques by code injection to increase the security and reliability of a software application. Also, the paper offers examples for binary code formats understanding and how the binary code injection may be applied.

  15. Statistical study of visual binaries

    Science.gov (United States)

    Abdel-Rahman, H. I.; Nouh, M. I.; Elsanhoury, W. H.

    2017-04-01

    In this paper, some statistical distributions of wide pairs included in Double Star Catalogue are investigated. Frequency distributions and testing hypothesis are derived for some basic parameters of visual binaries. The results reached indicate that, it was found that the magnitude difference is distributed exponentially, which means that the majority of the component of the selected systems is of the same spectral type. The distribution of the mass ratios is concentrated about 0.7 which agree with Salpeter mass function. The distribution of the linear separation appears to be exponentially, which contradict with previous studies for close binaries.

  16. Chromospheric Activity in Algol Binaries

    Science.gov (United States)

    1992-08-10

    Binaries J ’ st ..icaton...... Project Period: 10-01-91 to 09-30-94 BYDist! ibution I Current Date: August 10, 1992 Availability Codes Avail and I or...brightness of the secondary, )3 Persei is the only Algol binary for which there was strong evidence of starspot activity. In this case, the evidence...mospheric Ha emission on what was formerly assumed to be emission from circunistellar gas. In the study of 3 Persei , the P.I. (Richards 1992b: 1992c) assumed

  17. A Chaos Robustness Criterion for 2D Piecewise Smooth Map with Applications in Pseudorandom Number Generator and Image Encryption with Avalanche Effect

    Directory of Open Access Journals (Sweden)

    Dandan Han

    2016-01-01

    Full Text Available This study proposes a chaos robustness criterion for a kind of 2D piecewise smooth maps (2DPSMs. Using the chaos robustness criterion, one can easily determine the robust chaos parameter regions for some 2DPSMs. Combining 2DPSM with a generalized synchronization (GS theorem, this study introduces a novel 6-dimensional discrete GS chaotic system. Based on the system, a 216-word chaotic pseudorandom number generator (CPRNG is designed. The key space of the CPRNG is larger than 2996. Using the FIPS 140-2 test suit/generalized FIPS 140-2 test suit tests the randomness of the 1000 key streams consists of 20,000 bits generated by the CPRNG, the RC4 algorithm, and the ZUC algorithm, respectively. The numerical results show that the three algorithms do not have significant differences. The CPRNG and a stream encryption scheme with avalanche effect (SESAE are used to encrypt an image. The results demonstrate that the CPRNG is able to generate the avalanche effects which are similar to those generated via ideal CPRNGs. The SESAE with one-time-pad scheme makes any attackers have to use brute attacks to break our cryptographic system.

  18. Structure and selection in an autocatalytic binary polymer model

    DEFF Research Database (Denmark)

    Tanaka, Shinpei; Fellermann, Harold; Rasmussen, Steen

    2014-01-01

    An autocatalytic binary polymer system is studied as an abstract model for a chemical reaction network capable to evolve. Due to autocatalysis, long polymers appear spontaneously and their concentration is shown to be maintained at the same level as that of monomers. When the reaction starts from...... a pool of monomers, highly ordered populations with particular sequence patterns are dynamically selected out of a vast number of possible states. The interplay between the selected microscopic sequence patterns and the macroscopic cooperative structures is examined both analytically and in simulation....... Stability, fluctuations, and dynamic selection mechanisms are investigated for the involved self-organizing processes. Copyright (C) EPLA, 2014...

  19. Performance comparison of binary modulation schemes for visible light communication

    KAUST Repository

    Park, Kihong

    2015-09-11

    In this paper, we investigate the power spectral density of several binary modulation schemes including variable on-off keying, variable pulse position modulation, and pulse dual slope modulation which were previously proposed for visible light communication with dimming control. We also propose a novel slope-based modulation called differential chip slope modulation (DCSM) and develop a chip-based hard-decision receiver to demodulate the resulting signal, detect the chip sequence, and decode the input bit sequence. We show that the DCSM scheme can exploit spectrum density more efficiently than the reference schemes while providing an error rate performance comparable to them. © 2015 IEEE.

  20. Subluminous X-ray binaries

    NARCIS (Netherlands)

    Armas Padilla, M.

    2013-01-01

    The discovery of the first X-ray binary, Scorpius X-1, by Giacconi et al. (1962), marked the birth of X-ray astronomy. Following that discovery, many additional X-ray sources where found with the first generation of X-ray rockets and observatories (e.g., UHURU and Einstein). The short-timescale

  1. The Uses of Binary Thinking.

    Science.gov (United States)

    Elbow, Peter

    1993-01-01

    Argues that oppositional thinking, if handled in the right way, will serve as a way to avoid the very problems that Jonathan Culler and Paul de Mann are troubled by: "purity, order, and hierarchy." Asserts that binary thinking can serve to encourage difference--indeed, encourage nondominance, nontranscendence, instability, and disorder.…

  2. The Colors of Transneptunian Binaries

    Science.gov (United States)

    Benecchi, Susan D.; Noll, K. S.; Grundy, W. M.; Buie, M. W.; Stephens, D. C.; Levison, H. F.

    2008-09-01

    We report resolved photometry of the primary and secondary components of 22 transneptunian binaries obtained with the Hubble Space Telescope. We find the primary and secondary colors to be identical within our measurement uncertainties and correlated with a Spearman rank correlation probability of 99.983%. The V-I colors of the components span the full color range from 0.7 (neutral) to 1.5 (red) with a median uncertainty of 0.05 magnitudes. As a group, the binary colors are indistinguishable from that of the larger population of apparently single transneptunian objects. Whatever mechanism produced the colors of apparently single transneptunian objects acted equally on binary systems. The most likely explanation is that the colors of both single and binary transneptunian objects are primordial and indicative of their origin in a locally homogeneous, globally heterogeneous protoplanetary disk. Support for this research was provided by NASA through a grant from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.

  3. Misclassification in binary choice models

    Czech Academy of Sciences Publication Activity Database

    Meyer, B. D.; Mittag, Nikolas

    2017-01-01

    Roč. 200, č. 2 (2017), s. 295-311 ISSN 0304-4076 R&D Projects: GA ČR(CZ) GJ16-07603Y Institutional support: Progres-Q24 Keywords : measurement error * binary choice models * program take-up Subject RIV: AH - Economics Impact factor: 1.633, year: 2016

  4. Generating Constant Weight Binary Codes

    Science.gov (United States)

    Knight, D.G.

    2008-01-01

    The determination of bounds for A(n, d, w), the maximum possible number of binary vectors of length n, weight w, and pairwise Hamming distance no less than d, is a classic problem in coding theory. Such sets of vectors have many applications. A description is given of how the problem can be used in a first-year undergraduate computational…

  5. Tides in Close Binary Systems

    Science.gov (United States)

    Burkart, Joshua

    2014-09-01

    We consider three aspects of tidal interactions in close binary systems. 1) We first develop a framework for predicting and interpreting photometric observations of eccentric binaries, which we term tidal asteroseismology. In such systems, the Fourier transform of the observed lightcurve is expected to consist of pulsations at harmonics of the orbital frequency. We use linear stellar perturbation theory to predict the expected pulsation amplitude spectra. Our numerical model does not assume adiabaticity, and accounts for stellar rotation in the traditional approximation. We apply our model to the recently discovered Kepler system KOI-54, a 42-day face-on stellar binary with e=0.83. Our modeling yields pulsation spectra that are semi-quantitatively consistent with observations of KOI-54. KOI-54's spectrum also contains several nonharmonic pulsations, which can be explained by nonlinear three-mode coupling. 2) We next consider the situation of a white dwarf (WD) binary inspiraling due to the emission of gravitational waves. We show that resonance locks, previously considered in binaries with an early-type star, occur universally in WD binaries. In a resonance lock, the orbital and spin frequencies evolve in lockstep, so that the tidal forcing frequency is approximately constant and a particular normal mode remains resonant, producing efficient tidal dissipation and nearly synchronous rotation. We derive analytic formulas for the tidal quality factor and tidal heating rate during a g-mode resonance lock, and verify our results numerically. We apply our analysis to the 13-minute double-WD binary J0651, and show that our predictions are roughly consistent with observations. 3) Lastly, we examine the general dynamics of resonance locking in more detail. Previous analyses of resonance locking, including my own earlier work, invoke the adiabatic (a.k.a. Lorentzian) approximation for the mode amplitude, valid only in the limit of relatively strong mode damping. We relax

  6. Thirty-two phase sequences design with good autocorrelation ...

    Indian Academy of Sciences (India)

    Such sequences have been used in numerous real-world applications such as channel estimation ... Polyphase signal has larger main lobe-to-peak sidelobe ratio over binary signal of the same code length. ..... References. Barker R H 1953 Group synchronizing of binary digital system in Jackson W (Ed): Communication.

  7. Interactions in Massive Colliding Wind Binaries

    Directory of Open Access Journals (Sweden)

    Michael F. Corcoran

    2012-03-01

    Full Text Available There are observational difficulties determining dynamical masses of binary star components in the upper HR diagram both due to the scarcity of massive binary systems and spectral and photometric contamination produced by the strong wind outflows in these systems. We discuss how variable X-ray emission in these systems produced by wind-wind collisions in massive binaries can be used to constrain the system parameters, with application to two important massive binaries, Eta Carinae and WR 140.

  8. Massive star population synthesis with binaries

    OpenAIRE

    Vanbeveren, D.; Mennekens, N.

    2015-01-01

    We first give a short historical overview with some key facts of massive star population synthesis with binaries. We then discuss binary population codes and focus on two ingredients which are important for massive star population synthesis and which may be different in different codes. Population simulations with binaries is the third part where we consider the initial massive binary frequency, the RSG/WR and WC/WN and SNII/SNIbc number ratio's, the probable initial rotational velocity distr...

  9. Formation and evolution of compact binaries

    NARCIS (Netherlands)

    Sluijs, Marcel Vincent van der

    2006-01-01

    In this thesis we investigate the formation and evolution of compact binaries. Chapters 2 through 4 deal with the formation of luminous, ultra-compact X-ray binaries in globular clusters. We show that the proposed scenario of magnetic capture produces too few ultra-compact X-ray binaries to explain

  10. Testing predictive performance of binary choice models

    NARCIS (Netherlands)

    A.C.D. Donkers (Bas); B. Melenberg (Bertrand)

    2002-01-01

    textabstractBinary choice models occur frequently in economic modeling. A measure of the predictive performance of binary choice models that is often reported is the hit rate of a model. This paper develops a test for the outperformance of a predictor for binary outcomes over a naive prediction

  11. Division Unit for Binary Integer Decimals

    DEFF Research Database (Denmark)

    Lang, Tomas; Nannarelli, Alberto

    2009-01-01

    In this work, we present a radix-10 division unit that is based on the digit-recurrence algorithm and implements binary encodings (binary integer decimal or BID) for significands. Recent decimal division designs are all based on the binary coded decimal (BCD) encoding. We adapt the radix-10 digit...

  12. Binary Linear-Time Erasure Decoding for Non-Binary LDPC codes

    CERN Document Server

    Savin, Valentin

    2009-01-01

    In this paper, we first introduce the extended binary representation of non-binary codes, which corresponds to a covering graph of the bipartite graph associated with the non-binary code. Then we show that non-binary codewords correspond to binary codewords of the extended representation that further satisfy some simplex-constraint: that is, bits lying over the same symbol-node of the non-binary graph must form a codeword of a simplex code. Applied to the binary erasure channel, this description leads to a binary erasure decoding algorithm of non-binary LDPC codes, whose complexity depends linearly on the cardinality of the alphabet. We also give insights into the structure of stopping sets for non-binary LDPC codes, and discuss several aspects related to upper-layer FEC applications.

  13. Humans cannot consciously generate random numbers sequences: Polemic study.

    Science.gov (United States)

    Figurska, Małgorzata; Stańczyk, Maciej; Kulesza, Kamil

    2008-01-01

    It is widely believed, that randomness exists in Nature. In fact such an assumption underlies many scientific theories and is embedded in the foundations of quantum mechanics. Assuming that this hypothesis is valid one can use natural phenomena, like radioactive decay, to generate random numbers. Today, computers are capable of generating the so-called pseudorandom numbers. Such series of numbers are only seemingly random (bias in the randomness quality can be observed). Question whether people can produce random numbers, has been investigated by many scientists in the recent years. The paper "Humans can consciously generate random numbers sequences..." published recently in Medical Hypotheses made claims that were in many ways contrary to state of art; it also stated far-reaching hypotheses. So, we decided to repeat the experiments reported, with special care being taken of proper laboratory procedures. Here, we present the results and discuss possible implications in computer and other sciences.

  14. Detecting Malicious Code by Binary File Checking

    Directory of Open Access Journals (Sweden)

    Marius POPA

    2014-01-01

    Full Text Available The object, library and executable code is stored in binary files. Functionality of a binary file is altered when its content or program source code is changed, causing undesired effects. A direct content change is possible when the intruder knows the structural information of the binary file. The paper describes the structural properties of the binary object files, how the content can be controlled by a possible intruder and what the ways to identify malicious code in such kind of files. Because the object files are inputs in linking processes, early detection of the malicious content is crucial to avoid infection of the binary executable files.

  15. The population of single and binary white dwarfs of the Galactic bulge

    Science.gov (United States)

    Torres, S.; García-Berro, E.; Cojocaru, R.; Calamida, A.

    2018-02-01

    Recent Hubble Space Telescope observations have unveiled the white dwarf cooling sequence of the Galactic bulge. Although the degenerate sequence can be well fitted employing the most up-to-date theoretical cooling sequences, observations show a systematic excess of red objects that cannot be explained by the theoretical models of single carbon-oxygen white dwarfs of the appropriate masses. Here we present a population synthesis study of the white dwarf cooling sequence of the Galactic bulge that takes into account the populations of both single white dwarfs and binary systems containing at least one white dwarf. These calculations incorporate state-of-the-art cooling sequences for white dwarfs with hydrogen-rich and hydrogen-deficient atmospheres, for both white dwarfs with carbon-oxygen and helium cores, and also take into account detailed prescriptions of the evolutionary history of binary systems. Our Monte Carlo simulator also incorporates all the known observational biases. This allows us to model with a high degree of realism the white dwarf population of the Galactic bulge. We find that the observed excess of red stars can be partially attributed to white dwarf plus main sequence binaries, and to cataclysmic variables or dwarf novae. Our best fit is obtained with a higher binary fraction and an initial mass function slope steeper than standard values, as well as with the inclusion of differential reddening and blending. Our results also show that the possible contribution of double degenerate systems or young and thick-disk bulge stars is negligible.

  16. Mass transfer between binary stars

    Science.gov (United States)

    Modisette, J. L.; Kondo, Y.

    1980-01-01

    The transfer of mass from one component of a binary system to another by mass ejection is analyzed through a stellar wind mechanism, using a model which integrates the equations of motion, including the energy equation, with an initial static atmosphere and various temperature fluctuations imposed at the base of the star's corona. The model is applied to several situations and the energy flow is calculated along the line of centers between the two binary components, in the rotating frame of the system, thereby incorporating the centrifugal force. It is shown that relatively small disturbances in the lower chromosphere or photosphere can produce mass loss through a stellar wind mechanism, due to the amplification of the disturbance propagating into the thinner atmosphere. Since there are many possible sources of the disturbance, the model can be used to explain many mass ejection phenomena.

  17. Binary data regression: Weibull distribution

    Science.gov (United States)

    Caron, Renault; Polpo, Adriano

    2009-12-01

    The problem of estimation in binary response data has receivied a great number of alternative statistical solutions. Generalized linear models allow for a wide range of statistical models for regression data. The most used model is the logistic regression, see Hosmer et al. [6]. However, as Chen et al. [5] mentions, when the probability of a given binary response approaches 0 at a different rate than it approaches 1, symmetric linkages are inappropriate. A class of models based on Weibull distribution indexed by three parameters is introduced here. Maximum likelihood methods are employed to estimate the parameters. The objective of the present paper is to show a solution for the estimation problem under the Weibull model. An example showing the quality of the model is illustrated by comparing it with the alternative probit and logit models.

  18. Consequences of dynamical disruption and mass segregation for the binary frequencies of star clusters

    Energy Technology Data Exchange (ETDEWEB)

    Geller, Aaron M. [Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208 (United States); De Grijs, Richard [Kavli Institute for Astronomy and Astrophysics, Peking University, Yi He Yuan Lu 5, Hai Dian District, Beijing 100871 (China); Li, Chengyuan [Department of Astronomy, Peking University, Yi He Yuan Lu 5, Hai Dian District, Beijing 100871 (China); Hurley, Jarrod R., E-mail: a-geller@northwestern.edu [Centre for Astrophysics and Supercomputing, Swinburne University of Technology, VIC 3122 (Australia)

    2013-12-10

    The massive (13,000-26,000 M {sub ☉}) and young (15-30 Myr) Large Magellanic Cloud star cluster NGC 1818 reveals an unexpected increasing binary frequency with radius for F-type stars (1.3-2.2 M {sub ☉}). This is in contrast to many older star clusters that show a decreasing binary frequency with radius. We study this phenomenon with sophisticated N-body modeling, exploring a range of initial conditions, from smooth virialized density distributions to highly substructured and collapsing configurations. We find that many of these models can reproduce the cluster's observed properties, although with a modest preference for substructured initial conditions. Our models produce the observed radial trend in binary frequency through disruption of soft binaries (with semi-major axes, a ≳ 3000 AU), on approximately a crossing time (∼5.4 Myr), preferentially in the cluster core. Mass segregation subsequently causes the binaries to sink toward the core. After roughly one initial half-mass relaxation time (t {sub rh}(0) ∼ 340 Myr) the radial binary frequency distribution becomes bimodal, the innermost binaries having already segregated toward the core, leaving a minimum in the radial binary frequency distribution that marches outward with time. After 4-6 t {sub rh}(0), the rising distribution in the halo disappears, leaving a radial distribution that rises only toward the core. Thus, both a radial binary frequency distribution that falls toward the core (as observed for NGC 1818) and one that rises toward the core (as for older star clusters) can arise naturally from the same evolutionary sequence owing to binary disruption and mass segregation in rich star clusters.

  19. Slow Rotating Trojans: Tidally Synchronized Binaries?

    Science.gov (United States)

    Noll, Keith

    2017-08-01

    We propose HST observations of six slow-rotating Trojans to search for tidally synchronous binaries similar to the Patroclus binary system. A significant excess of slow rotators over Maxwellian suggests that additional binaries may be present. If any of the targets are binary, they can be resolved by HST. This target selection strategy has recently yielded the third known resolved Trojan binary, detected in a sample of seven slow-rotating Trojans. We wish to extend this successful strategy with another similarly selected sample. Even one additional resolved binary in the Trojans, which would become the fourth, would be of extreme interest. The discovery of no binaries among this group of slow rotators would challenge the understanding of the source of the excess slow rotators in the Trojans.

  20. Binary Multidimensional Scaling for Hashing.

    Science.gov (United States)

    Huang, Yameng; Lin, Zhouchen

    2017-10-04

    Hashing is a useful technique for fast nearest neighbor search due to its low storage cost and fast query speed. Unsupervised hashing aims at learning binary hash codes for the original features so that the pairwise distances can be best preserved. While several works have targeted on this task, the results are not satisfactory mainly due to the oversimplified model. In this paper, we propose a unified and concise unsupervised hashing framework, called Binary Multidimensional Scaling (BMDS), which is able to learn the hash code for distance preservation in both batch and online mode. In the batch mode, unlike most existing hashing methods, we do not need to simplify the model by predefining the form of hash map. Instead, we learn the binary codes directly based on the pairwise distances among the normalized original features by Alternating Minimization. This enables a stronger expressive power of the hash map. In the online mode, we consider the holistic distance relationship between current query example and those we have already learned, rather than only focusing on current data chunk. It is useful when the data come in a streaming fashion. Empirical results show that while being efficient for training, our algorithm outperforms state-of-the-art methods by a large margin in terms of distance preservation, which is practical for real-world applications.

  1. Close visual binaries. III. Parameters and evolutionary status

    Energy Technology Data Exchange (ETDEWEB)

    Corbally, C.J.

    1984-12-01

    New Yale isochrones, which have been tested for accuracy (Paper II), provide the means to investigate interesting visual binaries, especially those whose classifications and photometry do not match well (Paper I). Various parameters are deduced for those binaries which fitted the isochrones (e.g., ages, metal abundances, luminosities of peculiar stars); various solutions are systematically developed for those which did not fit, and a likely status of evolution proposed (e.g., duplicity of the components, pre-main-sequence, blue straggler, horizontal branch, optical pair, data inaccuracies). Evolution around the helium flash and diffusion theory are briefly considered. These parameters and statuses provide a wealth of new stellar data and suggestions for further investigation.

  2. Quantum memory receiver for superadditive communication using binary coherent states.

    Science.gov (United States)

    Klimek, Aleksandra; Jachura, Michał; Wasilewski, Wojciech; Banaszek, Konrad

    2016-11-12

    We propose a simple architecture based on multimode quantum memories for collective readout of classical information keyed using a pair coherent states, exemplified by the well-known binary phase shift keying format. Such a configuration enables demonstration of the superadditivity effect in classical communication over quantum channels, where the transmission rate becomes enhanced through joint detection applied to multiple channel uses. The proposed scheme relies on the recently introduced idea to prepare Hadamard sequences of input symbols that are mapped by a linear optical transformation onto the pulse position modulation format [Guha, S. Phys. Rev. Lett.2011, 106, 240502]. We analyze two versions of readout based on direct detection and an optional Dolinar receiver which implements the minimum-error measurement for individual detection of a binary coherent state alphabet.

  3. X-ray spectra and the rotation-activity connection of RS Canum Venaticorum binaries

    Science.gov (United States)

    Majer, P.; Schmitt, J. H. M. M.; Golub, L.; Harnden, F. R., Jr.; Rosner, R.

    1986-01-01

    Results are presented from a survey of RS CVn binaries which were observed with the imaging proportional counter (IPC) on board the Einstein Observatory. Spectral analyses of the IPC pulse height spectra show that the coronae of RS CVn binaries always contain hot gas with temperatures in excess of 10 to the 7th K, similar to active late-type main-sequence stars, and that at least two temperature components are necessary to account for the higher quality IPC spectra (when absorption is unimportant). It is argued that these bimodal temperature distributions found by the IPC are indicative of true distributions of emission measure versus temperature that are continuous (just as is the case of magnetically confined coronal plasma loops observed on the sun). It is further shown that none of the derivable X-ray characteristics of RS CVn binaries depend on rotation period, implying that previous claims of period-activity relationships in RS CVn binaries were unfounded.

  4. Binary Black Holes from Dense Star Clusters

    Science.gov (United States)

    Rodriguez, Carl

    2017-01-01

    The recent detections of gravitational waves from merging binary black holes have the potential to revolutionize our understanding of compact object astrophysics. But to fully utilize this new window into the universe, we must compare these observations to detailed models of binary black hole formation throughout cosmic time. In this talk, I will review our current understanding of cluster dynamics, describing how binary black holes can be formed through gravitational interactions in dense stellar environments, such as globular clusters and galactic nuclei. I will review the properties and merger rates of binary black holes from the dynamical formation channel. Finally, I will describe how the spins of a binary black hole are determined by its formation history, and how we can use this to discriminate between dynamically-formed binaries and those formed from isolated evolution in galactic fields.

  5. SYSTEMATICALLY MISCLASSIFIED BINARY DEPENDENT VARIABLES.

    Science.gov (United States)

    Tennekoon, Vidhura; Rosenman, Robert

    When a binary dependent variable is misclassified, that is, recorded in the category other than where it really belongs, probit and logit estimates are biased and inconsistent. In some cases the probability of misclassification may vary systematically with covariates, and thus be endogenous. In this paper we develop an estimation approach that corrects for endogenous misclassification, validate our approach using a simulation study, and apply it to the analysis of a treatment program designed to improve family dynamics. Our results show that endogenous misclassification could lead to potentially incorrect conclusions unless corrected using an appropriate technique.

  6. The structures of binary compounds

    CERN Document Server

    Hafner, J; Jensen, WB; Majewski, JA; Mathis, K; Villars, P; Vogl, P; de Boer, FR

    1990-01-01

    - Up-to-date compilation of the experimental data on the structures of binary compounds by Villars and colleagues. - Coloured structure maps which order the compounds into their respective structural domains and present for the first time the local co-ordination polyhedra for the 150 most frequently occurring structure types, pedagogically very helpful and useful in the search for new materials with a required crystal structure. - Crystal co-ordination formulas: a flexible notation for the interpretation of solid-state structures by chemist Bill Jensen. - Recent important advances in unders

  7. Microlensing Signature of Binary Black Holes

    Science.gov (United States)

    Schnittman, Jeremy; Sahu, Kailash; Littenberg, Tyson

    2012-01-01

    We calculate the light curves of galactic bulge stars magnified via microlensing by stellar-mass binary black holes along the line-of-sight. We show the sensitivity to measuring various lens parameters for a range of survey cadences and photometric precision. Using public data from the OGLE collaboration, we identify two candidates for massive binary systems, and discuss implications for theories of star formation and binary evolution.

  8. A Novel Partial Sequence Alignment Tool for Finding Large Deletions

    Directory of Open Access Journals (Sweden)

    Taner Aruk

    2012-01-01

    Full Text Available Finding large deletions in genome sequences has become increasingly more useful in bioinformatics, such as in clinical research and diagnosis. Although there are a number of publically available next generation sequencing mapping and sequence alignment programs, these software packages do not correctly align fragments containing deletions larger than one kb. We present a fast alignment software package, BinaryPartialAlign, that can be used by wet lab scientists to find long structural variations in their experiments. For BinaryPartialAlign, we make use of the Smith-Waterman (SW algorithm with a binary-search-based approach for alignment with large gaps that we called partial alignment. BinaryPartialAlign implementation is compared with other straight-forward applications of SW. Simulation results on mtDNA fragments demonstrate the effectiveness (runtime and accuracy of the proposed method.

  9. Speech perception of noise with binary gains

    DEFF Research Database (Denmark)

    Wang, DeLiang; Kjems, Ulrik; Pedersen, Michael Syskind

    2008-01-01

    For a given mixture of speech and noise, an ideal binary time-frequency mask is constructed by comparing speech energy and noise energy within local time-frequency units. It is observed that listeners achieve nearly perfect speech recognition from gated noise with binary gains prescribed by the i......For a given mixture of speech and noise, an ideal binary time-frequency mask is constructed by comparing speech energy and noise energy within local time-frequency units. It is observed that listeners achieve nearly perfect speech recognition from gated noise with binary gains prescribed...

  10. Binary and multiple systems of stars

    CERN Document Server

    Batten, Alan H

    1973-01-01

    Binary and Multiple Systems of Stars focuses on spectroscopic observational results and interpretations of binaries, and a few of multiple systems. Organized into 10 chapters, this book begins with the basic concepts and terminologies used in the study of binary and multiple systems of stars. Then, the incidence of both star systems is described. Subsequent chapters explore the properties of individual binaries, as well as the evolution and origin of such star system. This book will be a valuable reference material for astronomers, scientists in related fields, as well as graduate students.

  11. Survival of planets around shrinking stellar binaries.

    Science.gov (United States)

    Muñoz, Diego J; Lai, Dong

    2015-07-28

    The discovery of transiting circumbinary planets by the Kepler mission suggests that planets can form efficiently around binary stars. None of the stellar binaries currently known to host planets has a period shorter than 7 d, despite the large number of eclipsing binaries found in the Kepler target list with periods shorter than a few days. These compact binaries are believed to have evolved from wider orbits into their current configurations via the so-called Lidov-Kozai migration mechanism, in which gravitational perturbations from a distant tertiary companion induce large-amplitude eccentricity oscillations in the binary, followed by orbital decay and circularization due to tidal dissipation in the stars. Here we explore the orbital evolution of planets around binaries undergoing orbital decay by this mechanism. We show that planets may survive and become misaligned from their host binary, or may develop erratic behavior in eccentricity, resulting in their consumption by the stars or ejection from the system as the binary decays. Our results suggest that circumbinary planets around compact binaries could still exist, and we offer predictions as to what their orbital configurations should be like.

  12. Eliciting Subjective Probabilities with Binary Lotteries

    DEFF Research Database (Denmark)

    Harrison, Glenn W.; Martínez-Correa, Jimmy; Swarthout, J. Todd

    We evaluate the binary lottery procedure for inducing risk neutral behavior in a subjective belief elicitation task. Harrison, Martínez-Correa and Swarthout [2013] found that the binary lottery procedure works robustly to induce risk neutrality when subjects are given one risk task defined over...... objective probabilities. Drawing a sample from the same subject population, we find evidence that the binary lottery procedure induces linear utility in a subjective probability elicitation task using the Quadratic Scoring Rule. We also show that the binary lottery procedure can induce direct revelation...

  13. Automatic sequences

    CERN Document Server

    Haeseler, Friedrich

    2003-01-01

    Automatic sequences are sequences which are produced by a finite automaton. Although they are not random they may look as being random. They are complicated, in the sense of not being not ultimately periodic, they may look rather complicated, in the sense that it may not be easy to name the rule by which the sequence is generated, however there exists a rule which generates the sequence. The concept automatic sequences has special applications in algebra, number theory, finite automata and formal languages, combinatorics on words. The text deals with different aspects of automatic sequences, in particular:· a general introduction to automatic sequences· the basic (combinatorial) properties of automatic sequences· the algebraic approach to automatic sequences· geometric objects related to automatic sequences.

  14. HII 2407: AN ECLIPSING BINARY REVEALED BY K2 OBSERVATIONS OF THE PLEIADES

    Energy Technology Data Exchange (ETDEWEB)

    David, Trevor J.; Hillenbrand, Lynne A.; Zhang, Celia; Riddle, Reed L. [Department of Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Stauffer, John; Rebull, L. M. [Spitzer Science Center, California Institute of Technology, Pasadena, CA 91125 (United States); Cody, Ann Marie [NASA Ames Research Center, Mountain View, CA 94035 (United States); Conroy, Kyle; Stassun, Keivan G. [Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235 (United States); Pope, Benjamin; Aigrain, Suzanne; Gillen, Ed [Department of Physics, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom); Cameron, Andrew Collier [SUPA, School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, Fife KY16 9SS (United Kingdom); Barrado, David [Centro de Astrobiología, INTA-CSIC, Dpto. Astrofísica, ESAC Campus, P.O. Box 78, E-28691 Villanueva de la Cañada, Madrid (Spain); Isaacson, Howard; Marcy, Geoffrey W. [Department of Astronomy, University of California, Berkeley, CA 94720 (United States); Ziegler, Carl; Law, Nicholas M. [Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3255 (United States); Baranec, Christoph, E-mail: tjd@astro.caltech.edu [Institute for Astronomy, University of Hawai‘i at Mānoa, Hilo, HI 96720-2700 (United States)

    2015-11-20

    The star HII 2407 is a member of the relatively young Pleiades star cluster and was previously discovered to be a single-lined spectroscopic binary. It is newly identified here within Kepler/K2 photometric time series data as an eclipsing binary system. Mutual fitting of the radial velocity and photometric data leads to an orbital solution and constraints on fundamental stellar parameters. While the primary has arrived on the main sequence, the secondary is still pre-main sequence and we compare our results for the M/M{sub ⊙} and R/R{sub ⊙} values with stellar evolutionary models. We also demonstrate that the system is likely to be tidally synchronized. Follow-up infrared spectroscopy is likely to reveal the lines of the secondary, allowing for dynamically measured masses and elevating the system to benchmark eclipsing binary status.

  15. Binary particle swarm optimization for operon prediction.

    Science.gov (United States)

    Chuang, Li-Yeh; Tsai, Jui-Hung; Yang, Cheng-Hong

    2010-07-01

    An operon is a fundamental unit of transcription and contains specific functional genes for the construction and regulation of networks at the entire genome level. The correct prediction of operons is vital for understanding gene regulations and functions in newly sequenced genomes. As experimental methods for operon detection tend to be nontrivial and time consuming, various methods for operon prediction have been proposed in the literature. In this study, a binary particle swarm optimization is used for operon prediction in bacterial genomes. The intergenic distance, participation in the same metabolic pathway, the cluster of orthologous groups, the gene length ratio and the operon length are used to design a fitness function. We trained the proper values on the Escherichia coli genome, and used the above five properties to implement feature selection. Finally, our study used the intergenic distance, metabolic pathway and the gene length ratio property to predict operons. Experimental results show that the prediction accuracy of this method reached 92.1%, 93.3% and 95.9% on the Bacillus subtilis genome, the Pseudomonas aeruginosa PA01 genome and the Staphylococcus aureus genome, respectively. This method has enabled us to predict operons with high accuracy for these three genomes, for which only limited data on the properties of the operon structure exists.

  16. The Kepler Eclipsing Binary V2281 Cygni with Twin Stars

    Science.gov (United States)

    Koo, Jae-Rim; Lee, Jae Woo; Hong, Kyeongsoo

    2017-12-01

    We present the physical properties of the eclipsing binary V2281 Cyg, which shows a light-time effect due to a supposed tertiary component from its eclipse timing variation according to the Kepler observations. The high-resolution spectra and BVR photometric data of the system were obtained at Bohyunsan Optical Astronomy Observatory and Mount Lemmon Optical Astronomy Observatory, respectively. To determine the fundamental parameters of the eclipsing pair and its circumbinary object, we simultaneously analyzed the radial velocities, light curves, and eclipse times including the Kepler data. The masses and radii for the primary and secondary stars were determined with accuracy levels of approximately 2% and 1%, respectively, as follows: {M}1=1.61+/- 0.04 {M}⊙ and {M}2=1.60+/- 0.04 {M}⊙ , {R}1=1.94+/- 0.02 {R}⊙ and {R}2=1.93+/- 0.02 {R}⊙ . If its orbit is coplanar with the eclipsing binary, the period and semimajor axis of the third body were calculated to be {P}3b=4.1 years and {a}3b=4.06 {au}, respectively, and its mass is {M}3b=0.75 {M}⊙ . The evolutionary state of the system was investigated by comparing the masses and radii with theoretical models. The results demonstrate that V2281 Cyg is a detached eclipsing binary, which consists of twin main-sequence stars with an age of 1.5 Gyr.

  17. Method of all-optical frequency encoded decimal to binary and binary coded decimal, binary to gray, and gray to binary data conversion using semiconductor optical amplifiers

    Science.gov (United States)

    Garai, Sisir Kumar

    2011-07-01

    Conversion of optical data from decimal to binary format is very important in optical computing and optical signal processing. There are many binary code systems to represent decimal numbers, the most common being the binary coded decimal (BCD) and gray code system. There are a wide choice of BCD codes, one of which is a natural BCD having a weighted code of 8421, by means of which it is possible to represent a decimal number from 0 to 9 with a combination of 4bit binary digits. The reflected binary code, also known as the Gray code, is a binary numeral system where two successive values differ in only 1bit. The Gray code is very important in digital optical communication as it is used to prevent spurious output from optical switches as well as to facilitate error correction in digital communications in an optical domain. Here in this communication, the author proposes an all-optical frequency encoded method of ``:decimal to binary, BCD,'' ``binary to gray,'' and ``gray to binary'' data conversion using the high-speed switching actions of semiconductor optical amplifiers. To convert decimal numbers to a binary form, a frequency encoding technique is adopted to represent two binary bits, 0 and 1. The frequency encoding technique offers advantages over conventional encoding techniques in terms of less probability of bit errors and greater reliability. Here the author has exploited the polarization switch made of a semiconductor optical amplifier (SOA) and a property of nonlinear rotation of the state of polarization of the probe beam in SOA for frequency conversion to develop the method of frequency encoded data conversion.

  18. DNA as a Binary Code: How the Physical Structure of Nucleotide Bases Carries Information

    Science.gov (United States)

    McCallister, Gary

    2005-01-01

    The DNA triplet code also functions as a binary code. Because double-ring compounds cannot bind to double-ring compounds in the DNA code, the sequence of bases classified simply as purines or pyrimidines can encode for smaller groups of possible amino acids. This is an intuitive approach to teaching the DNA code. (Contains 6 figures.)

  19. Post common envelope binaries from SDSS. XII. The orbital period distribution

    Science.gov (United States)

    Nebot Gómez-Morán, A.; Gänsicke, B. T.; Schreiber, M. R.; Rebassa-Mansergas, A.; Schwope, A. D.; Southworth, J.; Aungwerojwit, A.; Bothe, M.; Davis, P. J.; Kolb, U.; Müller, M.; Papadaki, C.; Pyrzas, S.; Rabitz, A.; Rodríguez-Gil, P.; Schmidtobreick, L.; Schwarz, R.; Tappert, C.; Toloza, O.; Vogel, J.; Zorotovic, M.

    2011-12-01

    Context. The complexity of the common-envelope phase and of magnetic stellar wind braking currently limits our understanding of close binary evolution. Because of their intrinsically simple structure, observational population studies of white dwarf plus main sequence (WDMS) binaries can potentially test theoretical models and constrain their parameters. Aims: The Sloan Digital Sky Survey (SDSS) has provided a large and homogeneously selected sample of WDMS binaries, which we characterise in terms of orbital and stellar parameters. Methods: We have obtained radial velocity information for 385 WDMS binaries from follow-up spectroscopy and for an additional 861 systems from the SDSS subspectra. Radial velocity variations identify 191 of these WDMS binaries as post common-envelope binaries (PCEBs). Orbital periods of 58 PCEBs were subsequently measured, predominantly from time-resolved spectroscopy, bringing the total number of SDSS PCEBs with orbital parameters to 79. Observational biases inherent to this PCEB sample were evaluated through extensive Monte Carlo simulations. Results: We find that 21-24% of all SDSS WDMS binaries have undergone common-envelope evolution, which is in good agreement with published binary population models and high-resolution HST imaging of WDMS binaries unresolved from the ground. The bias-corrected orbital period distribution of PCEBs ranges from 1.9 h to 4.3 d and approximately follows a normal distribution in log (Porb), peaking at ~10.3 h. There is no observational evidence for a significant population of PCEBs with periods in the range of days to weeks. Conclusions: The large and homogeneous sample of SDSS WDMS binaries provides the means to test fundamental predictions of binary population models, hence to observationally constrain the evolution of all close compact binaries. Figures 3-6, Tables 1, 5 and Appendices are only available in electronic form at http://www.aanda.orgFull Tables 3, 4, and 6 are only available at the CDS via

  20. Binary Representations of Fingerprint Spectral Minutiae Features

    NARCIS (Netherlands)

    Xu, H.; Veldhuis, Raymond N.J.

    A fixed-length binary representation of a fingerprint has the advantages of a fast operation and a small template storage. For many biometric template protection schemes, a binary string is also required as input. The spectral minutiae representation is a method to represent a minutiae set as a

  1. Microlensing Binaries with Candidate Brown Dwarf Companions

    DEFF Research Database (Denmark)

    Shin, I.-G; Han, C.; Gould, A.

    2012-01-01

    Brown dwarfs are important objects because they may provide a missing link between stars and planets, two populations that have dramatically different formation histories. In this paper, we present the candidate binaries with brown dwarf companions that are found by analyzing binary microlensing ...

  2. Novel quantum inspired binary neural network algorithm

    Indian Academy of Sciences (India)

    In this paper, a quantum based binary neural network algorithm is proposed, named as novel quantum binary neural network algorithm (NQ-BNN). It forms a neural network structure by deciding weights and separability parameter in quantum based manner. Quantum computing concept represents solution probabilistically ...

  3. Binary trees equipped with semivaluations | Pajoohesh ...

    African Journals Online (AJOL)

    Our interest in this lattice stems from its application to binary decision trees. Binary decision trees form a crucial tool for algorithmic time analysis. The lattice properties of Tn are studied and we show that every Tn has a sublattice isomorphic to Tn-1 and prove that Tn is generated by Tn-1. Also we show that the distance from ...

  4. Binary Relations as a Foundation of Mathematics

    NARCIS (Netherlands)

    Kuper, Jan; Barendsen, E.; Capretta, V.; Geuvers, H.; Niqui, M.

    2007-01-01

    We describe a theory for binary relations in the Zermelo-Fraenkel style. We choose for ZFCU, a variant of ZFC Set theory in which the Axiom of Foundation is replaced by an axiom allowing for non-wellfounded sets. The theory of binary relations is shown to be equi-consistent ZFCU by constructing a

  5. Binaries with the eyes of CTA

    NARCIS (Netherlands)

    Paredes, J.M.; Bednarek, W.; Bordas, P.; Bosch-Ramon, V.; De Cea del Pozo, E.; Dubus, G.; Funk, S.; Hadasch, D.; Khangulyan, D.; Markoff, S.; Moldón, J.; Munar-Adrover, P.; Nagataki, S.; Naito, T.; de Naurois, M.; Pedaletti, G.; Reimer, O.; Ribó, M.; Szostek, A.; Terada, Y.; Torres, D.F.; Zabalza, V.; Zdziarski, A.A.

    2013-01-01

    The binary systems that have been detected in gamma rays have proven very useful to study high-energy processes, in particular particle acceleration, emission and radiation reprocessing, and the dynamics of the underlying magnetized flows. Binary systems, either detected or potential gamma-ray

  6. The Evolution of Compact Binary Star Systems

    Directory of Open Access Journals (Sweden)

    Yungelson, Lev R.

    2006-12-01

    Full Text Available We review the formation and evolution of compact binary stars consisting of white dwarfs (WDs, neutron stars (NSs, and black holes (BHs. Binary NSs and BHs are thought to be the primary astrophysical sources of gravitational waves (GWs within the frequency band of ground-based detectors, while compact binaries of WDs are important sources of GWs at lower frequencies to be covered by space interferometers (LISA. Major uncertainties in the current understanding of properties of NSs and BHs most relevant to the GW studies are discussed, including the treatment of the natal kicks which compact stellar remnants acquire during the core collapse of massive stars and the common envelope phase of binary evolution. We discuss the coalescence rates of binary NSs and BHs and prospects for their detections, the formation and evolution of binary WDs and their observational manifestations. Special attention is given to AM CVn-stars -- compact binaries in which the Roche lobe is filled by another WD or a low-mass partially degenerate helium-star, as these stars are thought to be the best LISA verification binary GW sources.

  7. The Evolution of Compact Binary Star Systems

    Directory of Open Access Journals (Sweden)

    Konstantin A. Postnov

    2014-05-01

    Full Text Available We review the formation and evolution of compact binary stars consisting of white dwarfs (WDs, neutron stars (NSs, and black holes (BHs. Mergings of compact-star binaries are expected to be the most important sources for forthcoming gravitational-wave (GW astronomy. In the first part of the review, we discuss observational manifestations of close binaries with NS and/or BH components and their merger rate, crucial points in the formation and evolution of compact stars in binary systems, including the treatment of the natal kicks, which NSs and BHs acquire during the core collapse of massive stars and the common envelope phase of binary evolution, which are most relevant to the merging rates of NS-NS, NS-BH and BH-BH binaries. The second part of the review is devoted mainly to the formation and evolution of binary WDs and their observational manifestations, including their role as progenitors of cosmologically-important thermonuclear SN Ia. We also consider AM CVn-stars, which are thought to be the best verification binary GW sources for future low-frequency GW space interferometers.

  8. Flexible link functions in nonparametric binary regression with Gaussian process priors.

    Science.gov (United States)

    Li, Dan; Wang, Xia; Lin, Lizhen; Dey, Dipak K

    2016-09-01

    In many scientific fields, it is a common practice to collect a sequence of 0-1 binary responses from a subject across time, space, or a collection of covariates. Researchers are interested in finding out how the expected binary outcome is related to covariates, and aim at better prediction in the future 0-1 outcomes. Gaussian processes have been widely used to model nonlinear systems; in particular to model the latent structure in a binary regression model allowing nonlinear functional relationship between covariates and the expectation of binary outcomes. A critical issue in modeling binary response data is the appropriate choice of link functions. Commonly adopted link functions such as probit or logit links have fixed skewness and lack the flexibility to allow the data to determine the degree of the skewness. To address this limitation, we propose a flexible binary regression model which combines a generalized extreme value link function with a Gaussian process prior on the latent structure. Bayesian computation is employed in model estimation. Posterior consistency of the resulting posterior distribution is demonstrated. The flexibility and gains of the proposed model are illustrated through detailed simulation studies and two real data examples. Empirical results show that the proposed model outperforms a set of alternative models, which only have either a Gaussian process prior on the latent regression function or a Dirichlet prior on the link function. © 2015, The International Biometric Society.

  9. Record-Breaking Eclipsing Binary

    Science.gov (United States)

    Kohler, Susanna

    2016-05-01

    A new record holder exists for the longest-period eclipsing binary star system: TYC-2505-672-1. This intriguing system contains a primary star that is eclipsed by its companion once every 69 years with each eclipse lasting several years!120 Years of ObservationsIn a recent study, a team of scientists led by Joseph Rodriguez (Vanderbilt University) characterizes the components of TYC-2505-672-1. This binary star system consists of an M-type red giant star that undergoes a ~3.45-year-long, near-total eclipse with a period of ~69.1 years. This period is more than double that of the previous longest-period eclipsing binary!Rodriguez and collaborators combined photometric observations of TYC-2505-672-1 by the Kilodegree Extremely Little Telescope (KELT) with a variety of archival data, including observations by the American Association of Variable Star Observers (AAVSO) network and historical data from the Digital Access to a Sky Century @ Harvard (DASCH) program.In the 120 years spanned by these observations, two eclipses are detected: one in 1942-1945 and one in 2011-2015. The authors use the observations to analyze the components of the system and attempt to better understand what causes its unusual light curve.Characterizing an Unusual SystemObservations of TYC-2505-672-1 plotted from 1890 to 2015 reveal two eclipses. (The blue KELT observations during the eclipse show upper limits only.) [Rodriguez et al. 2016]By modeling the systems emission, Rodriguez and collaborators establish that TYC-2505-672-1 consists of a 3600-K primary star thats the M giant orbited by a small, hot, dim companion thats a toasty 8000 K. But if the companion is small, why does the eclipse last several years?The authors argue that the best model of TYC-2505-672-1 is one in which the small companion star is surrounded by a large, opaque circumstellar disk. Rodriguez and collaborators suggest that the companion could be a former red giant whose atmosphere was stripped from it, leaving behind

  10. Accurate and fast 3D surface measurement with temporal-spatial binary encoding structured illumination.

    Science.gov (United States)

    Zhu, Jiangping; Zhou, Pei; Su, Xianyu; You, Zhisheng

    2016-12-12

    Balancing the accuracy and speed for 3D surface measurement of object is crucial in many important applications. Binary encoding pattern utilizing the high-speed image switching rate of digital mirror device (DMD)-based projector could be used as the candidate for fast even high-speed 3D measurement, but current most schemes only enable the measurement speed, which limit their application scopes. In this paper, we present a binary encoding method and develop an experimental system aiming to solve such a situation. Our approach encodes one computer-generated standard 8 bit sinusoidal fringe pattern into multiple binary patterns (sequence) with designed temporal-spatial binary encoding tactics. The binary pattern sequence is then high-speed and in-focus projected onto the surface of tested object, and then captured by means of temporal-integration imaging to form one sinusoidal fringe image. Further the combination of phase-shifting technique and temporal phase unwrapping algorithm leads to fast and accurate 3D measurement. The systematic accuracy better than 0.08mm is achievable. The measurement results with mask and palm are given to confirm the feasibility.

  11. The Evolution of the Multiplicity of Embedded Protostars. II. Binary Separation Distribution and Analysis

    Science.gov (United States)

    Connelley, Michael S.; Reipurth, Bo; Tokunaga, Alan T.

    2008-06-01

    We present the Class I protostellar binary separation distribution based on the data tabulated in a companion paper. We verify the excess of Class I binary stars over solar-type main-sequence stars in the separation range from 500 AU to 4500 AU. Although our sources are in nearby star-forming regions distributed across the entire sky (including Orion), none of our objects are in a high stellar density environment. A log-normal function, used by previous authors to fit the main-sequence and T Tauri binary separation distributions, poorly fits our data, and we determine that a log-uniform function is a better fit. Our observations show that the binary separation distribution changes significantly during the Class I phase, and that the binary frequency at separations greater than 1000 AU declines steadily with respect to spectral index. Despite these changes, the binary frequency remains constant until the end of the Class I phase, when it drops sharply. We propose a scenario to account for the changes in the Class I binary separation distribution. This scenario postulates that a large number of companions with a separation greater than ~1000 AU were ejected during the Class 0 phase, but remain gravitationally bound due to the significant mass of the Class I envelope. As the envelope dissipates, these companions become unbound and the binary frequency at wide separations declines. Circumstellar and circumbinary disks are expected to play an important role in the orbital evolution at closer separations. This scenario predicts that a large number of Class 0 objects should be non-hierarchical multiple systems, and that many Class I young stellar objects (YSOs) with a widely separated companion should also have a very close companion. We also find that Class I protostars are not dynamically pristine, but have experienced dynamical evolution before they are visible as Class I objects. Our analysis shows that the Class I binary frequency and the binary separation

  12. Scheme for Entering Binary Data Into a Quantum Computer

    Science.gov (United States)

    Williams, Colin

    2005-01-01

    A quantum algorithm provides for the encoding of an exponentially large number of classical data bits by use of a smaller (polynomially large) number of quantum bits (qubits). The development of this algorithm was prompted by the need, heretofore not satisfied, for a means of entering real-world binary data into a quantum computer. The data format provided by this algorithm is suitable for subsequent ultrafast quantum processing of the entered data. Potential applications lie in disciplines (e.g., genomics) in which one needs to search for matches between parts of very long sequences of data. For example, the algorithm could be used to encode the N-bit-long human genome in only log2N qubits. The resulting log2N-qubit state could then be used for subsequent quantum data processing - for example, to perform rapid comparisons of sequences.

  13. Pointwise intensity-based dynamic speckle analysis with binary patterns

    Science.gov (United States)

    Stoykova, Elena; Mateev, Georgy; Nazarova, Dimana; Berberova, Nataliya; Ivanov, Branimir

    2017-06-01

    Non-destructive detection of physical or biological activity through statistical processing of speckle patterns on the surface of diffusely reflecting objects is an area of active research. A lot of pointwise intensity-based algorithms have been proposed over the recent years. Efficiency of these algorithms is deteriorated by the signal-dependent speckle data, non-uniform illumination or varying reflectivity across the object, especially when the number of the acquired speckle patterns is limited. Pointwise processing of a sequence of 2D images is also time-consuming. In this paper, we propose to transform the acquired speckle images into binary patterns by using for a sign threshold the mean intensity value estimated at each spatial point from the temporal sequence of intensities at this point. Activity is characterized by the 2D distribution of a temporal polar correlation function estimated at a given time lag from the binary patterns. Processing of synthetic and experimental data confirmed that the algorithm provided correct activity determination with the same accuracy as the temporal normalized correlation function. It is efficient without the necessity to apply normalization at non-uniform distribution of intensity in the illuminating laser beam and offers acceleration of computation.

  14. A millisecond pulsar in an extremely wide binary system

    Science.gov (United States)

    Bassa, C. G.; Janssen, G. H.; Stappers, B. W.; Tauris, T. M.; Wevers, T.; Jonker, P. G.; Lentati, L.; Verbiest, J. P. W.; Desvignes, G.; Graikou, E.; Guillemot, L.; Freire, P. C. C.; Lazarus, P.; Caballero, R. N.; Champion, D. J.; Cognard, I.; Jessner, A.; Jordan, C.; Karuppusamy, R.; Kramer, M.; Lazaridis, K.; Lee, K. J.; Liu, K.; Lyne, A. G.; McKee, J.; Osłowski, S.; Perrodin, D.; Sanidas, S.; Shaifullah, G.; Smits, R.; Theureau, G.; Tiburzi, C.; Zhu, W. W.

    2016-08-01

    We report on 22 yr of radio timing observations of the millisecond pulsar J1024-0719 by the telescopes participating in the European Pulsar Timing Array (EPTA). These observations reveal a significant second derivative of the pulsar spin frequency and confirm the discrepancy between the parallax and Shklovskii distances that has been reported earlier. We also present optical astrometry, photometry and spectroscopy of 2MASS J10243869-0719190. We find that it is a low-metallicity main-sequence star (K7V spectral type, [M/H] = -1.0, Teff = 4050 ± 50 K) and that its position, proper motion and distance are consistent with those of PSR J1024-0719. We conclude that PSR J1024-0719 and 2MASS J10243869-0719190 form a common proper motion pair and are gravitationally bound. The gravitational interaction between the main-sequence star and the pulsar accounts for the spin frequency derivatives, which in turn resolves the distance discrepancy. Our observations suggest that the pulsar and main-sequence star are in an extremely wide (Pb > 200 yr) orbit. Combining the radial velocity of the companion and proper motion of the pulsar, we find that the binary system has a high spatial velocity of 384 ± 45 km s-1 with respect to the local standard of rest and has a Galactic orbit consistent with halo objects. Since the observed main-sequence companion star cannot have recycled the pulsar to millisecond spin periods, an exotic formation scenario is required. We demonstrate that this extremely wide-orbit binary could have evolved from a triple system that underwent an asymmetric supernova explosion, though find that significant fine-tuning during the explosion is required. Finally, we discuss the implications of the long period orbit on the timing stability of PSR J1024-0719 in light of its inclusion in pulsar timing arrays.

  15. DIFFERENT DYNAMICAL AGES FOR THE TWO YOUNG AND COEVAL LMC STAR CLUSTERS, NGC 1805 AND NGC 1818, IMPRINTED ON THEIR BINARY POPULATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Geller, Aaron M. [Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States); Grijs, Richard de; Li, Chengyuan [Kavli Institute for Astronomy and Astrophysics, Peking University, Yi He Yuan Lu 5, Hai Dian District, Beijing 100871 (China); Hurley, Jarrod R., E-mail: a-geller@northwestern.edu [Centre for Astrophysics and Supercomputing, Swinburne University of Technology, VIC 3122 (Australia)

    2015-05-20

    The two Large Magellanic Cloud star clusters, NGC 1805 and NGC 1818, are approximately the same chronological age (∼30 Myr), but show different radial trends in binary frequency. The F-type stars (1.3–2.2 M{sub ⊙}) in NGC 1818 have a binary frequency that decreases toward the core, while the binary frequency for stars of similar mass in NGC 1805 is flat with radius, or perhaps bimodal (with a peak in the core). We show here, through detailed N-body modeling, that both clusters could have formed with the same primordial binary frequency and with binary orbital elements and masses drawn from the same distributions (defined from observations of open clusters and the field of our Galaxy). The observed radial trends in binary frequency for both clusters are best matched with models that have initial substructure. Furthermore, both clusters may be evolving along a very similar dynamical sequence, with the key difference that NGC 1805 is dynamically older than NGC 1818. The F-type binaries in NGC 1818 still show evidence of an initial period of rapid dynamical disruptions (which occur preferentially in the core), while NGC 1805 has already begun to recover a higher core binary frequency, owing to mass segregation (which will eventually produce a distribution in binary frequency that rises only toward the core, as is observed in old Milky Way star clusters). This recovery rate increases for higher-mass binaries, and therefore even at one age in one cluster, we predict a similar dynamical sequence in the radial distribution of the binary frequency as a function of binary primary mass.

  16. Topological and categorical properties of binary trees

    Directory of Open Access Journals (Sweden)

    H. Pajoohesh

    2008-04-01

    Full Text Available Binary trees are very useful tools in computer science for estimating the running time of so-called comparison based algorithms, algorithms in which every action is ultimately based on a prior comparison between two elements. For two given algorithms A and B where the decision tree of A is more balanced than that of B, it is known that the average and worst case times of A will be better than those of B, i.e., ₸A(n ≤₸B(n and TWA (n≤TWB (n. Thus the most balanced and the most imbalanced binary trees play a main role. Here we consider them as semilattices and characterize the most balanced and the most imbalanced binary trees by topological and categorical properties. Also we define the composition of binary trees as a commutative binary operation, *, such that for binary trees A and B, A * B is the binary tree obtained by attaching a copy of B to any leaf of A. We show that (T,* is a commutative po-monoid and investigate its properties.

  17. Embedded binaries and their dense cores

    Science.gov (United States)

    Sadavoy, Sarah I.; Stahler, Steven W.

    2017-08-01

    We explore the relationship between young, embedded binaries and their parent cores, using observations within the Perseus Molecular Cloud. We combine recently published Very Large Array observations of young stars with core properties obtained from Submillimetre Common-User Bolometer Array 2 observations at 850 μm. Most embedded binary systems are found towards the centres of their parent cores, although several systems have components closer to the core edge. Wide binaries, defined as those systems with physical separations greater than 500 au, show a tendency to be aligned with the long axes of their parent cores, whereas tight binaries show no preferred orientation. We test a number of simple, evolutionary models to account for the observed populations of Class 0 and I sources, both single and binary. In the model that best explains the observations, all stars form initially as wide binaries. These binaries either break up into separate stars or else shrink into tighter orbits. Under the assumption that both stars remain embedded following binary break-up, we find a total star formation rate of 168 Myr-1. Alternatively, one star may be ejected from the dense core due to binary break-up. This latter assumption results in a star formation rate of 247 Myr-1. Both production rates are in satisfactory agreement with current estimates from other studies of Perseus. Future observations should be able to distinguish between these two possibilities. If our model continues to provide a good fit to other star-forming regions, then the mass fraction of dense cores that becomes stars is double what is currently believed.

  18. Binary supergratings: Aperiodic optics for spectral engineering

    Science.gov (United States)

    Fay, Martin Freestone

    The Binary Supergrating (BSG) is an aperiodic guided-wave optical device which, in parallel to the much-touted Photonic Band Gap, represents the extension of the Bragg grating into frequency space. The result is an easily manufactured two-level refractive index profile offering fully customizable spectral characteristics, including wavelength-dependent control over beam direction, dispersion and power. As a general concept, a BSG can be synthesized using a variety of approaches, ranging from a simple threshold quantization of the emulated ideal analog index profile to more sophisticated delta-sigma modulator (DSM) methods, which preserve diffraction characteristics over a specified band of interest with high fidelity. The comparative advantages of each are explored in the context of their tolerance to manufacturing variances. For most cases, the BSG designs degrade gracefully and retain their functionality under extreme errors in fabrication. However, particular vulnerabilities do emerge, along with strategies to mitigate their effect. The BSG is then demonstrated experimentally, in a first proof-of-concept embodiment employing a lateral satellite grating configuration, which eases fabrication by having both waveguide and grating features defined in the same lithographic sequence. Results from this passive optical device corroborate both the BSG's design flexibility and its particular vulnerabilities, yielding clear directions for subsequent implementations. In the domain of active BSG-enabled devices, the novel self-collimated multi-wavelength laser (SCMWL) outputs low-divergence beams at multiple simultaneous wavelengths. The concept, theory, and design of this invention is presented, followed by experimental results from optically pumped proof-of-concept embodiments. The observed spectra confirm the SCMWL concept, while also revealing the complex dynamics underlying this device. At once simple and subtle, the BSG concept yields itself both for immediate

  19. Instabilities in Interacting Binary Stars

    Science.gov (United States)

    Andronov, I. L.; Andrych, K. D.; Antoniuk, K. A.; Baklanov, A. V.; Beringer, P.; Breus, V. V.; Burwitz, V.; Chinarova, L. L.; Chochol, D.; Cook, L. M.; Cook, M.; Dubovský, P.; Godlowski, W.; Hegedüs, T.; Hoňková, K.; Hric, L.; Jeon, Y.-B.; Juryšek, J.; Kim, C.-H.; Kim, Y.; Kim, Y.-H.; Kolesnikov, S. V.; Kudashkina, L. S.; Kusakin, A. V.; Marsakova, V. I.; Mason, P. A.; Mašek, M.; Mishevskiy, N.; Nelson, R. H.; Oksanen, A.; Parimucha, S.; Park, J.-W.; Petrík, K.; Quiñones, C.; Reinsch, K.; Robertson, J. W.; Sergey, I. M.; Szpanko, M.; Tkachenko, M. G.; Tkachuk, L. G.; Traulsen, I.; Tremko, J.; Tsehmeystrenko, V. S.; Yoon, J.-N.; Zola, S.; Shakhovskoy, N. M.

    2017-07-01

    The types of instability in the interacting binary stars are briefly reviewed. The project “Inter-Longitude Astronomy” is a series of smaller projects on concrete stars or groups of stars. It has no special funds, and is supported from resources and grants of participating organizations, when informal working groups are created. This “ILA” project is in some kind similar and complementary to other projects like WET, CBA, UkrVO, VSOLJ, BRNO, MEDUZA, AstroStatistics, where many of us collaborate. Totally we studied 1900+ variable stars of different types, including newly discovered variables. The characteristic timescale is from seconds to decades and (extrapolating) even more. The monitoring of the first star of our sample AM Her was initiated by Prof. V.P. Tsesevich (1907-1983). Since more than 358 ADS papers were published. In this short review, we present some highlights of our photometric and photo-polarimetric monitoring and mathematical modeling of interacting binary stars of different types: classical (AM Her, QQ Vul, V808 Aur = CSS 081231:071126+440405, FL Cet), asynchronous (BY Cam, V1432 Aql), intermediate (V405 Aql, BG CMi, MU Cam, V1343 Her, FO Aqr, AO Psc, RXJ 2123, 2133, 0636, 0704) polars and magnetic dwarf novae (DO Dra) with 25 timescales corresponding to different physical mechanisms and their combinations (part “Polar”); negative and positive superhumpers in nova-like (TT Ari, MV Lyr, V603 Aql, V795 Her) and many dwarf novae stars (“Superhumper”); eclipsing “non-magnetic” cataclysmic variables(BH Lyn, DW UMa, EM Cyg; PX And); symbiotic systems (“Symbiosis”); super-soft sources (SSS, QR And); spotted (and not spotted) eclipsing variables with (and without) evidence for a current mass transfer (“Eclipser”) with a special emphasis on systems with a direct impact of the stream into the gainer star's atmosphere, which we propose to call “Impactor” (short from “Extreme Direct Impactor”), or V361 Lyr-type stars. Other

  20. Binary neutron star merger simulations

    Energy Technology Data Exchange (ETDEWEB)

    Bruegmann, Bernd [Jena Univ. (Germany)

    2016-11-01

    Our research focuses on the numerical tools necessary to solve Einstein's equations. In recent years we have been particularly interested in spacetimes consisting of two neutron stars in the final stages of their evolution. Because of the emission of gravitational radiation, the objects are driven together to merge; the emitted gravitational wave signal is visualized. This emitted gravitational radiation carries energy and momentum away from the system and contains information about the system. Late last year the Laser Interferometer Gravitational-wave Observatory (LIGO) began searches for these gravitational wave signals at a sensitivity at which detections are expected. Although such systems can radiate a significant amount of their total mass-energy in gravitational waves, the gravitational wave signals one expects to receive on Earth are not strong, since sources of gravitational waves are often many millions of light years away. Therefore one needs accurate templates for the radiation one expects from such systems in order to be able to extract them out of the detector's noise. Although analytical models exist for compact binary systems when the constituents are well separated, we need numerical simulation to investigate the last orbits before merger to obtain accurate templates and validate analytical approximations. Due to the strong nonlinearity of the equations and the large separation of length scales, these simulations are computationally demanding and need to be run on large supercomputers. When matter is present the computational cost as compared to pure black hole (vacuum) simulations increases even more due to the additional matter fields. But also more interesting astrophysical phenomena can happen. In fact, there is the possibility for a strong electromagnetic signal from the merger (e.g., a short gamma-ray burst or lower-energy electromagnetic signatures from the ejecta) and significant neutrino emission. Additionally, we can expect that

  1. Calibrating binary lumped parameter models

    Science.gov (United States)

    Morgenstern, Uwe; Stewart, Mike

    2017-04-01

    Groundwater at its discharge point is a mixture of water from short and long flowlines, and therefore has a distribution of ages rather than a single age. Various transfer functions describe the distribution of ages within the water sample. Lumped parameter models (LPMs), which are mathematical models of water transport based on simplified aquifer geometry and flow configuration can account for such mixing of groundwater of different age, usually representing the age distribution with two parameters, the mean residence time, and the mixing parameter. Simple lumped parameter models can often match well the measured time varying age tracer concentrations, and therefore are a good representation of the groundwater mixing at these sites. Usually a few tracer data (time series and/or multi-tracer) can constrain both parameters. With the building of larger data sets of age tracer data throughout New Zealand, including tritium, SF6, CFCs, and recently Halon-1301, and time series of these tracers, we realised that for a number of wells the groundwater ages using a simple lumped parameter model were inconsistent between the different tracer methods. Contamination or degradation of individual tracers is unlikely because the different tracers show consistent trends over years and decades. This points toward a more complex mixing of groundwaters with different ages for such wells than represented by the simple lumped parameter models. Binary (or compound) mixing models are able to represent a more complex mixing, with mixing of water of two different age distributions. The problem related to these models is that they usually have 5 parameters which makes them data-hungry and therefore difficult to constrain all parameters. Two or more age tracers with different input functions, with multiple measurements over time, can provide the required information to constrain the parameters of the binary mixing model. We obtained excellent results using tritium time series encompassing

  2. Dynamical mass transfer in cataclysmic binaries

    Science.gov (United States)

    Melia, Fulvio; Lamb, D. Q.

    1987-01-01

    When a binary comes into contact and mass transfer begins, orbital angular momentum is stored in the accretion disk until the disk couples tidally to the binary system. Taam and McDermott (1987) have suggested that this leads to unstable dynamical mass transfer in many cataclysmic variables in which mass transfer would otherwise be stable, and that it explains the gap between 2 and 3 h in the orbital period distribution of these systems. Here the consequences of this hypothesis for the evolution of cataclysmic binaries are explored. It is found that systems coming into contact longward of the period gap undergo one or more episodes of dynamical mass transfer.

  3. Eliciting Subjective Probabilities with Binary Lotteries

    DEFF Research Database (Denmark)

    Harrison, Glenn W.; Martínez-Correa, Jimmy; Swarthout, J. Todd

    2014-01-01

    We evaluate a binary lottery procedure for inducing risk neutral behavior in a subjective belief elicitation task. Prior research has shown this procedure to robustly induce risk neutrality when subjects are given a single risk task defined over objective probabilities. Drawing a sample from...... the same subject population, we find evidence that the binary lottery procedure also induces linear utility in a subjective probability elicitation task using the Quadratic Scoring Rule. We also show that the binary lottery procedure can induce direct revelation of subjective probabilities in subjects...

  4. Sequence assembly

    DEFF Research Database (Denmark)

    Scheibye-Alsing, Karsten; Hoffmann, S.; Frankel, Annett Maria

    2009-01-01

    Despite the rapidly increasing number of sequenced and re-sequenced genomes, many issues regarding the computational assembly of large-scale sequencing data have remain unresolved. Computational assembly is crucial in large genome projects as well for the evolving high-throughput technologies...... and plays an important role in processing the information generated by these methods. Here, we provide a comprehensive overview of the current publicly available sequence assembly programs. We describe the basic principles of computational assembly along with the main concerns, such as repetitive sequences...... in genomic DNA, highly expressed genes and alternative transcripts in EST sequences. We summarize existing comparisons of different assemblers and provide a detailed descriptions and directions for download of assembly programs at: http://genome.ku.dk/resources/assembly/methods.html....

  5. Estimating the Binary Fraction of Central Stars of Planetary Nebulae

    Science.gov (United States)

    Douchin, Dimitri

    2015-01-01

    fraction is larger than what we may expect based on the main-sequence progenitor population binary fraction and therefore conclude that binarity is a preferential channel for the formation of planetary nebulae. I finish by underlining the need for a sample size of ˜150 objects to decrease the uncertainty on the planetary nebula population binary fraction and increase the statistical significance of this result.

  6. Dixie Valley Bottoming Binary Unit

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, Dale [Terra-Gen Sierra Holdings, LLC, Reno, NV (United States)

    2014-12-21

    This binary plant is the first air cooled, high-output refrigeration based waste heat recovery cycle in the industry. Its working fluid is environmentally friendly and as such, the permits that would be required with a hydrocarbon based cycle are not necessary. The unit is largely modularized, meaning that the unit’s individual skids were assembled in another location and were shipped via truck to the plant site. The Air Cooled Condensers (ACC), equipment piping, and Balance of Plant (BOP) piping were constructed at site. This project further demonstrates the technical feasibility of using low temperature brine for geothermal power utilization. The development of the unit led to the realization of low temperature, high output, and environmentally friendly heat recovery systems through domestic research and engineering. The project generates additional renewable energy, resulting in cleaner air and reduced carbon dioxide emissions. Royalty and tax payments to governmental agencies will increase, resulting in reduced financial pressure on local entities. The major components of the unit were sourced from American companies, resulting in increased economic activity throughout the country.

  7. Genome Sequencing

    DEFF Research Database (Denmark)

    Sato, Shusei; Andersen, Stig Uggerhøj

    2014-01-01

    The current Lotus japonicus reference genome sequence is based on a hybrid assembly of Sanger TAC/BAC, Sanger shotgun and Illumina shotgun sequencing data generated from the Miyakojima-MG20 accession. It covers nearly all expressed L. japonicus genes and has been annotated mainly based...... on transcriptional evidence. Analysis of repetitive sequences suggests that they are underrepresented in the reference assembly, reflecting an enrichment of gene-rich regions in the current assembly. Characterization of Lotus natural variation by resequencing of L. japonicus accessions and diploid Lotus species...... is currently ongoing, facilitated by the MG20 reference sequence...

  8. BINARY MINOR PLANETS V4.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The data set lists orbital and physical properties for well-observed or suspected binary/multiple minor planets including the Pluto system, as inspired by Richardson...

  9. Binary Biometric Representation through Pairwise Polar Quantization

    NARCIS (Netherlands)

    Chen, C.; Veldhuis, Raymond N.J.; Tistarelli, M.; Nixon, M.

    Binary biometric representations have great significance for data compression and template protection. In this paper, we introduce pairwise polar quantization. Furthermore, aiming to optimize the discrimination between the genuine Hamming distance (GHD) and the imposter Hamming distance (IHD), we

  10. On the Maximum Separation of Visual Binaries

    Indian Academy of Sciences (India)

    2016-01-27

    minimum) angular separation ρmax(ρmin), the corresponding apparent position angles (|ρmax , |ρmin) and the individual masses of visual binary systems. The algorithm uses Reed's formulae (1984) for the masses, and a ...

  11. BINARY MINOR PLANETS V6.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The data set lists orbital and physical properties for well-observed or suspected binary/multiple minor planets including the Pluto system, as inspired by Richardson...

  12. BINARY MINOR PLANETS V5.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The data set lists orbital and physical properties for well-observed or suspected binary/multiple minor planets including the Pluto system, as inspired by Richardson...

  13. BINARY MINOR PLANETS V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — We present a data table giving basic physical and orbital parameters for known binary minor planets in the Solar System (and Pluto/Charon) based on published...

  14. BINARY MINOR PLANETS V8.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The data set lists orbital and physical properties for well-observed or suspected binary/multiple minor planets including the Pluto system, compiled from the...

  15. BINARY MINOR PLANETS V2.0

    Data.gov (United States)

    National Aeronautics and Space Administration — We present data tables giving basic orbital and physical parameters for well-observed or suspected binary/multiple minor planets and the Pluto system, based on a...

  16. BINARY MINOR PLANETS V9.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The data set lists orbital and physical properties for well-observed or suspected binary/multiple minor planets including the Pluto system, compiled from the...

  17. BINARY MINOR PLANETS V3.0

    Data.gov (United States)

    National Aeronautics and Space Administration — We present data tables giving basic orbital and physical parameters for well-observed or suspected binary/multiple minor planets and the Pluto system, based on a...

  18. BINARY MINOR PLANETS V7.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The data set lists orbital and physical properties for well-observed or suspected binary/multiple minor planets including the Pluto system, compiled from the...

  19. Optimized reversible binary-coded decimal adders

    DEFF Research Database (Denmark)

    Thomsen, Michael Kirkedal; Glück, Robert

    2008-01-01

    Abstract Babu and Chowdhury [H.M.H. Babu, A.R. Chowdhury, Design of a compact reversible binary coded decimal adder circuit, Journal of Systems Architecture 52 (5) (2006) 272-282] recently proposed, in this journal, a reversible adder for binary-coded decimals. This paper corrects and optimizes....... Keywords: Reversible logic circuit; Full-adder; Half-adder; Parallel adder; Binary-coded decimal; Application of reversible logic synthesis......) BCD addition, the circuit delay of 49 gates is significantly lower than is the number of bits used for the BCD representation. A complete set of reversible half- and full-adders for n-bit binary numbers and m-decimal BCD numbers is presented. The results show that special-purpose design pays off...

  20. Eclipsing Binary Stars: Modeling and Analysis

    CERN Document Server

    Kallrath, Josef

    2009-01-01

    Eclipsing Binary Stars focuses on the mathematical formulation of astrophysical models for the light curves of eclipsing binaries stars, and on the algorithms for evaluating and exploiting such models. Since information gained from binary systems provides much of what we know of the masses, luminosities, and radii of stars, such modeling is acquiring increasing importance in studies of stellar structure and evolution. As in other areas of science, the computer revolution has given many astronomers tools that previously only specialists could use; anyone with access to a set of data can now expect to be able to model it. This book will provide astronomers, both amateurs and professionals, with a guide for • specifying an astrophysical model for a set of observations • selecting an algorithm to determine the parameters of the model • estimating the errors of the parameters Eclipsing Binary Stars is written for readers familiar with basic calculus and linear algebra; appendices cover mathematical details o...

  1. Low-mass X-ray binary evolution and the origin of millisecond pulsars

    Science.gov (United States)

    Frank, Juhan; King, Andrew R.; Lasota, Jean-Pierre

    1992-01-01

    The evolution of low-mass X-ray binaries (LMXBs) is considered. It is shown that X-ray irradiation of the companion stars causes these systems to undergo episodes of rapid mass transfer followed by detached phases. The systems are visible as bright X-ray binaries only for a short part of each cycle, so that their space density must be considerably larger than previously estimated. This removes the difficulty in regarding LMXBs as the progenitors of low-mass binary pulsars. The low-accretion-rate phase of the cycle with the soft X-ray transients is identified. It is shown that 3 hr is likely to be the minimum orbital period for LMXBs with main-sequence companions and it is suggested that the evolutionary endpoint for many LMXBs may be systems which are the sites of gamma-ray bursts.

  2. Serial binary interval ratios improve rhythm reproduction

    OpenAIRE

    Xiang eWu; Anders eWestanmo; Liang eZhou; Junhao ePan

    2013-01-01

    Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are bett...

  3. Surface Phases in Binary Liquid Metal Alloys

    OpenAIRE

    Tostmann, Holger; DiMasi, Elaine; Shpyrko, Oleg G.; Ocko, Ben M.; Pershan, Peter S.; Deutsch, Moshe

    2004-01-01

    Surface sensitive x-ray scattering techniques with atomic scale resolution are employed to investigate the microscopic structure of the surface of three classes of liquid binary alloys: (i) Surface segregation in partly miscible binary alloys as predicted by the Gibbs adsorption rule is investigated for Ga-In. The first layer consists of a supercooled In monolayer and the bulk composition is reached after about two atomic diameters. (ii) The Ga-Bi system displays a wetting transition at a cha...

  4. An Introduction to Binary Decision Diagrams

    DEFF Research Database (Denmark)

    Andersen, Henrik Reif

    1996-01-01

    This note is a short introduction to Binary Decision Diagrams (BDDs). It provides some background knowledge and describes the core algorithms. It is used in the course "C4340 Advanced Algorithms" at the Technical University of Denmark, autumn 1996.......This note is a short introduction to Binary Decision Diagrams (BDDs). It provides some background knowledge and describes the core algorithms. It is used in the course "C4340 Advanced Algorithms" at the Technical University of Denmark, autumn 1996....

  5. Texture classification by texton: statistical versus binary.

    Directory of Open Access Journals (Sweden)

    Zhenhua Guo

    Full Text Available Using statistical textons for texture classification has shown great success recently. The maximal response 8 (Statistical_MR8, image patch (Statistical_Joint and locally invariant fractal (Statistical_Fractal are typical statistical texton algorithms and state-of-the-art texture classification methods. However, there are two limitations when using these methods. First, it needs a training stage to build a texton library, thus the recognition accuracy will be highly depended on the training samples; second, during feature extraction, local feature is assigned to a texton by searching for the nearest texton in the whole library, which is time consuming when the library size is big and the dimension of feature is high. To address the above two issues, in this paper, three binary texton counterpart methods were proposed, Binary_MR8, Binary_Joint, and Binary_Fractal. These methods do not require any training step but encode local feature into binary representation directly. The experimental results on the CUReT, UIUC and KTH-TIPS databases show that binary texton could get sound results with fast feature extraction, especially when the image size is not big and the quality of image is not poor.

  6. Close encounters of the third-body kind. [intruding bodies in binary star systems

    Science.gov (United States)

    Davies, M. B.; Benz, W.; Hills, J. G.

    1994-01-01

    We simulated encounters involving binaries of two eccentricities: e = 0 (i.e., circular binaries) and e = 0.5. In both cases the binary contained a point mass of 1.4 solar masses (i.e., a neutron star) and a 0.8 solar masses main-sequence star modeled as a polytrope. The semimajor axes of both binaries were set to 60 solar radii (0.28 AU). We considered intruders of three masses: 1.4 solar masses (a neutron star), 0.8 solar masses (a main-sequence star or a higher mass white dwarf), and 0.64 solar masses (a more typical mass white dwarf). Our strategy was to perform a large number (40,000) of encounters using a three-body code, then to rerun a small number of cases with a three-dimensional smoothed particle hydrodynamics (SPH) code to determine the importance of hydrodynamical effects. Using the results of the three-body runs, we computed the exchange across sections, sigma(sub ex). From the results of the SPH runs, we computed the cross sections for clean exchange, denoted by sigma(sub cx); the formation of a triple system, denoted by sigma(sub trp); and the formation of a merged binary with an object formed from the merger of two of the stars left in orbit around the third star, denoted by sigma(sub mb). For encounters between either binary and a 1.4 solar masses neutron star, sigma(sub cx) approx. 0.7 sigma(sub ex) and sigma(sub mb) + sigma(sub trp) approx. 0.3 sigma(sub ex). For encounters between either binary and the 0.8 solar masses main-sequence star, sigma(sub cx) approx. 0.50 sigma(sub ex) and sigma(sub mb) + sigma(sub trp) approx. 1.0 sigma(sub ex). If the main sequence star is replaced by a main-sequence star of the same mass, we have sigma(sub cx) approx. 0.5 sigma(sub ex) and sigma(sub mb) + sigma(sub trp) approx. 1.6 sigma(sub ex). Although the exchange cross section is a sensitive function of intruder mass, we see that the cross section to produce merged binaries is roughly independent of intruder mass. The merged binaries produced have semi

  7. A novel method for comparative analysis of DNA sequences by Ramanujan-Fourier transform.

    Science.gov (United States)

    Yin, Changchuan; Yin, Xuemeng E; Wang, Jiasong

    2014-12-01

    Alignment-free sequence analysis approaches provide important alternatives over multiple sequence alignment (MSA) in biological sequence analysis because alignment-free approaches have low computation complexity and are not dependent on high level of sequence identity. However, most of the existing alignment-free methods do not employ true full information content of sequences and thus can not accurately reveal similarities and differences among DNA sequences. We present a novel alignment-free computational method for sequence analysis based on Ramanujan-Fourier transform (RFT), in which complete information of DNA sequences is retained. We represent DNA sequences as four binary indicator sequences and apply RFT on the indicator sequences to convert them into frequency domain. The Euclidean distance of the complete RFT coefficients of DNA sequences are used as similarity measures. To address the different lengths of RFT coefficients in Euclidean space, we pad zeros to short DNA binary sequences so that the binary sequences equal the longest length in the comparison sequence data. Thus, the DNA sequences are compared in the same dimensional frequency space without information loss. We demonstrate the usefulness of the proposed method by presenting experimental results on hierarchical clustering of genes and genomes. The proposed method opens a new channel to biological sequence analysis, classification, and structural module identification.

  8. Pseudo-random-bit-sequence phase modulation for reduced errors in a fiber optic gyroscope.

    Science.gov (United States)

    Chamoun, Jacob; Digonnet, Michel J F

    2016-12-15

    Low noise and drift in a laser-driven fiber optic gyroscope (FOG) are demonstrated by interrogating the sensor with a low-coherence laser. The laser coherence was reduced by broadening its optical spectrum using an external electro-optic phase modulator driven by either a sinusoidal or a pseudo-random bit sequence (PRBS) waveform. The noise reduction measured in a FOG driven by a modulated laser agrees with the calculations based on the broadened laser spectrum. Using PRBS modulation, the linewidth of a laser was broadened from 10 MHz to more than 10 GHz, leading to a measured FOG noise of only 0.00073  deg/√h and a drift of 0.023  deg/h. To the best of our knowledge, these are the lowest noise and drift reported in a laser-driven FOG, and this noise is below the requirement for the inertial navigation of aircraft.

  9. ROTATIONAL SYNCHRONIZATION MAY ENHANCE HABITABILITY FOR CIRCUMBINARY PLANETS: KEPLER BINARY CASE STUDIES

    Energy Technology Data Exchange (ETDEWEB)

    Mason, Paul A. [Department of Physics, University of Texas at El Paso, El Paso, TX 79968 (United States); Zuluaga, Jorge I.; Cuartas-Restrepo, Pablo A. [FACom-Instituto de Fisica-FCEN, Universidad de Antioquia, Calle 70 No. 52-21, Medellin (Colombia); Clark, Joni M. [Department of Mathematics and Physical Sciences, New Mexico State University-DACC, Las Cruces, NM 88003 (United States)

    2013-09-10

    We report a mechanism capable of reducing (or increasing) stellar activity in binary stars, thereby potentially enhancing (or destroying) circumbinary habitability. In single stars, stellar aggression toward planetary atmospheres causes mass-loss, which is especially detrimental for late-type stars, because habitable zones are very close and activity is long lasting. In binaries, tidal rotational breaking reduces magnetic activity, thus reducing harmful levels of X-ray and ultraviolet (XUV) radiation and stellar mass-loss that are able to erode planetary atmospheres. We study this mechanism for all confirmed circumbinary (p-type) planets. We find that main sequence twins provide minimal flux variation and in some cases improved environments if the stars rotationally synchronize within the first Gyr. Solar-like twins, like Kepler 34 and Kepler 35, provide low habitable zone XUV fluxes and stellar wind pressures. These wide, moist, habitable zones may potentially support multiple habitable planets. Solar-type stars with lower mass companions, like Kepler 47, allow for protected planets over a wide range of secondary masses and binary periods. Kepler 38 and related binaries are marginal cases. Kepler 64 and analogs have dramatically reduced stellar aggression due to synchronization of the primary, but are limited by the short lifetime. Kepler 16 appears to be inhospitable to planets due to extreme XUV flux. These results have important implications for estimates of the number of stellar systems containing habitable planets in the Galaxy and allow for the selection of binaries suitable for follow-up searches for habitable planets.

  10. Performance Analysis of New Binary User Codes for DS-CDMA Communication

    Science.gov (United States)

    Usha, Kamle; Jaya Sankar, Kottareddygari

    2016-03-01

    This paper analyzes new binary spreading codes through correlation properties and also presents their performance over additive white Gaussian noise (AWGN) channel. The proposed codes are constructed using gray and inverse gray codes. In this paper, a n-bit gray code appended by its n-bit inverse gray code to construct the 2n-length binary user codes are discussed. Like Walsh codes, these binary user codes are available in sizes of power of two and additionally code sets of length 6 and their even multiples are also available. The simple construction technique and generation of code sets of different sizes are the salient features of the proposed codes. Walsh codes and gold codes are considered for comparison in this paper as these are popularly used for synchronous and asynchronous multi user communications respectively. In the current work the auto and cross correlation properties of the proposed codes are compared with those of Walsh codes and gold codes. Performance of the proposed binary user codes for both synchronous and asynchronous direct sequence CDMA communication over AWGN channel is also discussed in this paper. The proposed binary user codes are found to be suitable for both synchronous and asynchronous DS-CDMA communication.

  11. WIYN open cluster study. LX. Spectroscopic binary orbits in NGC 6819

    Energy Technology Data Exchange (ETDEWEB)

    Milliman, Katelyn E.; Mathieu, Robert D.; Gosnell, Natalie M. [Department of Astronomy, University of Wisconsin-Madison, 475 North Charter Street Madison, WI 53706 (United States); Geller, Aaron M. [Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA), Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States); Meibom, Søren [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Platais, Imants, E-mail: milliman@astro.wisc.edu [Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218 (United States)

    2014-08-01

    We present the current state of the WOCS radial-velocity (RV) survey for the rich open cluster NGC 6819 (2.5 Gyr) including 93 spectroscopic binary orbits with periods ranging from 1.5 to 8000 days. These results are the product of our ongoing RV survey of NGC 6819 using the Hydra Multi-Object Spectrograph on the WIYN 3.5 m telescope. We also include a detailed analysis of multiple prior sets of optical photometry for NGC 6819. Within a 1° field of view, our stellar sample includes the giant branch, the red clump, and blue straggler candidates, and extends to almost 2 mag below the main sequence (MS) turnoff. For each star observed in our survey we present all RV measurements, the average RV, and velocity variability information. Additionally, we discuss notable binaries from our sample, including eclipsing binaries (WOCS 23009, WOCS 24009, and WOCS 40007), stars noted in Kepler asteroseismology studies (WOCS 4008, WOCS 7009, and WOCS 8007), and potential descendants of past blue stragglers (WOCS 1006 and WOCS 6002). We find the incompleteness-corrected binary fraction for all MS binaries with periods less than 10{sup 4} days to be 22% ± 3% and a tidal circularization period of 6.2{sub −1.1}{sup +1.1} days for NGC 6819.

  12. Is the Binary Mass Ratio Distribution Separation-Dependent?

    Science.gov (United States)

    Gullikson, Kevin; Kraus, Adam L.

    2016-01-01

    Recent discoveries of planets orbiting retired A-stars on close orbits and young A-stars on very wide orbits have renewed interest in the properties of nearby intermediate-mass stars. Especially interesting are the young stars because directly-imaged planets orbiting them may be bright enough for characterization (e.g. HR 8799, Beta Pictoris, etc). However, intermediate-mass stars and especially young intermediate mass stars are part of multiple systems more often than not. Close stellar companions may affect the formation and orbital evolution of any planets, and the properties of the companions can help constrain the binary formation mechanism. The mass ratio distribution of a population of binary stars, especially if the distribution for close companions is significantly different from that of wide companions, is helpful to distinguish companions that were born in or affected by the circumstellar disk from those which formed through fragmentation of the molecular core. Previous imaging surveys have found that binary systems with A-type primary stars tend to have cool companions with extreme mass ratios. There are hints at a much flatter mass ratio distribution for close companions, but strong completeness effects complicate the picture. We have conducted a spectroscopic survey of ~400 nearby main sequence A- and B-type stars, aimed at detecting stellar companions as late as M4 for all orbital separations <100 AU. We have searched for companions to the stars by cross-correlating the spectra against model templates for F-M type stars; a significant peak in the cross-correlation function indicates a detection. Our cross-correlation technique can detect low-mass companions with orbits that are too wide to detect with radial velocity monitoring and too small to detect with imaging techniques, making it complementary to work already done. We will present results from our survey and compare the mass ratio distribution we measure to the corresponding distribution for

  13. Non-approximability of weighted multiple sequence alignment for arbitrary metrics

    NARCIS (Netherlands)

    Manthey, Bodo

    2005-01-01

    We prove that the multiple sequence alignment problem with weighted sum-of-pairs score is APX-hard for arbitrary metric scoring functions over the binary alphabet. This holds even when the weights are restricted to zero and one.

  14. Modelling of binary stars from observations. (Italian Title: Creare modelli di stelle binarie dalle osservazioni)

    Science.gov (United States)

    Marino, G.

    2011-08-01

    A review on basic physical parameters of closed binary stars introduces to modelling observational data. PHOEBE and other modelling software are described. As example of application, for the first time photometric elements of the eclipsing binary V400 Lyr are obtained.

  15. Absolute parameters of southern eclipsing binary: MW Pup

    Science.gov (United States)

    Sürgit, D.; Erdem, A.; Engelbrecht, C. A.

    2015-02-01

    This paper presents the first analysis of spectroscopic and photometric observations of the southern eclipsing binary star MW Pup. ASAS V light and SAAO radial velocity curves of the system were solved simultaneously using Wilson-Devinney code. The results describe MW Pup as an Algol-like binary star with a detached configuration. The masses of the components were found to be 2.20 ± 0.06 and 1.88 ± 0.07 M⊙ and the radii to be 1.84 ± 0.03 and 1.72 ± 0.03 R⊙ for primary and secondary components, respectively. The distance to MW Pup was calculated to be 430 ± 30 pc from the dynamic parallax, neglecting interstellar absorption, in agreement with the value derived from the eclipse-parallax method. The evolution of the system is also discussed. Both components are unevolved Main Sequence stars and the dynamic age of the system is estimated as 263 ± 70 My when compared to theoretical evolution models.

  16. Do stellar clusters form fewer binaries? Using moderate separation binaries to distinguish between nature and nurture

    Science.gov (United States)

    Reiter, Megan

    2017-08-01

    Fewer wide-separation binaries are found in dense stellar clusters than in looser stellar associations. It is therefore unclear whether feedback in clusters prevents the formation of multiple systems or dynamical interactions destroy them. Measuring the prevalence of close, bound binary systems provide a key test to distinguish between these possibilities. Systems with separations of 10-50 AU will survive interactions in the cluster environment, and therefore are more representative of the natal population of multiple systems. By fitting a double-star PSF, we will identify visual binaries in the Orion Nebula with separations as small as 0.03. At the distance of Orion, this corresponds to a physical separation of 12 AU, effectively closing the observational gap in the binary separation distribution left between known visual and spectroscopic binaries (>65 AU or thesis.

  17. Serial binary interval ratios improve rhythm reproduction

    Directory of Open Access Journals (Sweden)

    Xiang eWu

    2013-08-01

    Full Text Available Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8, non-binary integer (1:3:5:6, and non-integer (1:2.3:5.3:6.4 ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception.

  18. Serial binary interval ratios improve rhythm reproduction.

    Science.gov (United States)

    Wu, Xiang; Westanmo, Anders; Zhou, Liang; Pan, Junhao

    2013-01-01

    Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8), non-binary integer (1:3:5:6), and non-integer (1:2.3:5.3:6.4) ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception.

  19. Urey Prize Lecture: Binary Minor Planets

    Science.gov (United States)

    Margot, J. L.

    2004-11-01

    The discovery of binary systems in the near-Earth, main belt, and Kuiper belt populations provides an abundance of new data that expand our knowledge of the physics and chemistry of the solar system. Binary minor planets form as a result of collisional, tidal, and capture processes that are important to study as they play major roles in the formation and evolution of planetary systems. The frequency of occurrence of such processes directly reflects the dynamical environment in the various populations. Observations of binaries provide a powerful way to measure the bulk properties of small bodies, which in turn lead to inferences about their composition and internal structure. These data may offer a rare glimpse of what physical and chemical conditions prevailed when protoplanets formed, and what subsequent evolution took place. In the case of the Kuiper Belt, the study of a handful of binaries forces us to rethink how dense and how bright these bodies are, and to significantly revise our current mass estimates for the entire population. The number of known binary minor planets has increased dramatically over the past few years, with roughly ten new discoveries each year. I will attempt to summarize recent developments, with examples drawn from my observations with the Hubble, Palomar, Keck, Arecibo and Goldstone telescopes.

  20. Satisfiability modulo theory and binary puzzle

    Science.gov (United States)

    Utomo, Putranto

    2017-06-01

    The binary puzzle is a sudoku-like puzzle with values in each cell taken from the set {0, 1}. We look at the mathematical theory behind it. A solved binary puzzle is an n × n binary array where n is even that satisfies the following conditions: (1) No three consecutive ones and no three consecutive zeros in each row and each column, (2) Every row and column is balanced, that is the number of ones and zeros must be equal in each row and in each column, (3) Every two rows and every two columns must be distinct. The binary puzzle had been proven to be an NP-complete problem [5]. Research concerning the satisfiability of formulas with respect to some background theory is called satisfiability modulo theory (SMT). An SMT solver is an extension of a satisfiability (SAT) solver. The notion of SMT can be used for solving various problem in mathematics and industries such as formula verification and operation research [1, 7]. In this paper we apply SMT to solve binary puzzles. In addition, we do an experiment in solving different sizes and different number of blanks. We also made comparison with two other approaches, namely by a SAT solver and exhaustive search.

  1. Stacking Analysis of Binary Systems with HAWC

    Science.gov (United States)

    Brisbois, Chad; HAWC Collaboration

    2017-01-01

    Detecting binary systems at TeV energies is an important problem because only a handful of such systems are currently known. The nature of such systems is typically thought to be composed of a compact object and a massive star. The TeV emission from these systems does not obviously correspond to emission in GeV or X-ray, where many binary systems have previously been found. This study focuses on a stacking method to detect TeV emission from LS 5039, a known TeV binary, to test its efficacy in HAWC data. Stacking is a widely employed method for increasing signal to noise ratio in optical astronomy, but has never been attempted previously with HAWC. HAWC is an ideal instrument to search for TeV binaries, because of its wide field of view and high uptime. Applying this method to the entire sky may allow HAWC to detect binary sources of very short or very long periods not sensitive to current analyses. NSF, DOE, Los Alamos, Michigan Tech, CONACyt, UNAM, BUAP.

  2. Evolution of Motion of a Binary Planet

    Science.gov (United States)

    Vil'ke, V. G.; Shatina, A. V.

    2001-05-01

    A model of a binary planet, consisting of a material point of small mass and a deformable viscoelastic sphere, is suggested. The center of mass of the binary planet moves in the gravitational field of a central body in the plane, which contains planets forming the binary planet. A deformable spherical planet rotates around the axis orthogonal to the plane of planetary motion. Planet deformations are described by the linear theory of viscoelasticity. It is shown that with an appropriate approximation of the gravitational potential, there is a class of quasicircular orbits, when the eccentricities of an orbit of the center of mass of a binary planet and an orbit, describing mutual planet motion, are equal to zero. The further evolution of motion is investigated in this class of orbits with the use of the canonical Poincare-Andoyer variables. Corresponding averaged equations are found, and phase pictures are constructed; the stability of stationary solutions is investigated on the basis of equations in variations. For the Solar system planets with their satellites, forming binary planets, the application of the presented model allows us to conclude that satellites sooner or later will fall on the corresponding planets.

  3. Radiance Data Assimilation for Binary Typhoon Cases

    Science.gov (United States)

    Choi, Y.; Snyder, C.; Cha, D. H.

    2015-12-01

    The predictability of track and intensity for binary tropical cyclones (TCs) is relatively low due to the interaction between two TCs. In this study, radiance data were assimilated using the Three Dimensional Variational (3D-Var) data assimilation method to improve track and intensity forecasts of binary TCs. In detail, a total of three binary TC cases over the Northwestern Pacific from 2010 to 2015, which affected the Korean Peninsula, were selected. Infrared and microwave radiance data from multiple instruments and satellites were assimilated with the appropriate treatments of quality control, channel selection, bias correction, and cloud detection. The Weather Research and Forecasting (WRF) model was used as a forecasting model, and the resolution of the innermost domain was high (2 km) to capture the structure and intensity of TCs. Background error covariance was calculated using the National Meteorological Center (NMC) method, where background error statistics were from the differences between 24-h and 12-h forecasts for a month-long period. Overall, track and intensity errors of three binary TCs are reduced through the assimilation of radiance data. Especially, track forecasts are improved significantly because large-scale environments such as the North Pacific High and mid-latitude trough/ridge are simulated well. Analysis increment and its evolution are investigated to reveal the reason for the improvement of each binary TC's forecast, focusing on TC's internal structure and its environment. Additionally, effects of other observational data (e.g. radiosonde, satellite wind) are analyzed through the sensitivity experiments.

  4. Spherical hashing: binary code embedding with hyperspheres.

    Science.gov (United States)

    Heo, Jae-Pil; Lee, Youngwoon; He, Junfeng; Chang, Shih-Fu; Yoon, Sung-Eui

    2015-11-01

    Many binary code embedding schemes have been actively studied recently, since they can provide efficient similarity search, and compact data representations suitable for handling large scale image databases. Existing binary code embedding techniques encode high-dimensional data by using hyperplane-based hashing functions. In this paper we propose a novel hypersphere-based hashing function, spherical hashing, to map more spatially coherent data points into a binary code compared to hyperplane-based hashing functions. We also propose a new binary code distance function, spherical Hamming distance, tailored for our hypersphere-based binary coding scheme, and design an efficient iterative optimization process to achieve both balanced partitioning for each hash function and independence between hashing functions. Furthermore, we generalize spherical hashing to support various similarity measures defined by kernel functions. Our extensive experiments show that our spherical hashing technique significantly outperforms state-of-the-art techniques based on hyperplanes across various benchmarks with sizes ranging from one to 75 million of GIST, BoW and VLAD descriptors. The performance gains are consistent and large, up to 100 percent improvements over the second best method among tested methods. These results confirm the unique merits of using hyperspheres to encode proximity regions in high-dimensional spaces. Finally, our method is intuitive and easy to implement.

  5. SMA OBSERVATIONS OF CLASS 0 PROTOSTARS: A HIGH ANGULAR RESOLUTION SURVEY OF PROTOSTELLAR BINARY SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Chen Xuepeng [Purple Mountain Observatory, Chinese Academy of Sciences, 2 West Beijing Road, Nanjing 210008 (China); Arce, Hector G.; Dunham, Michael M. [Department of Astronomy, Yale University, Box 208101, New Haven, CT 06520-8101 (United States); Zhang Qizhou; Bourke, Tyler L. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Launhardt, Ralf; Henning, Thomas [Max Planck Institute for Astronomy, Koenigstuhl 17, D-69117 Heidelberg (Germany); Jorgensen, Jes K. [Niels Bohr Institute and Centre for Star and Planet Formation, Copenhagen University, Juliane Maries Vej 30, DK-2100 Copenhagen O (Denmark); Lee, Chin-Fei [Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 106, Taiwan (China); Foster, Jonathan B. [Institute for Astrophysical Research, Boston University, Boston, MA 02215 (United States); Pineda, Jaime E., E-mail: xpchen@pmo.ac.cn, E-mail: xuepeng.chen@yale.edu [ESO, Karl Schwarzschild Str. 2, D-85748 Garching bei Munchen (Germany)

    2013-05-10

    We present high angular resolution 1.3 mm and 850 {mu}m dust continuum data obtained with the Submillimeter Array toward 33 Class 0 protostars in nearby clouds (distance < 500 pc), which represents so far the largest survey toward protostellar binary/multiple systems. The median angular resolution in the survey is 2.''5, while the median linear resolution is approximately 600 AU. Compact dust continuum emission is observed from all sources in the sample. Twenty-one sources in the sample show signatures of binarity/multiplicity, with separations ranging from 50 AU to 5000 AU. The numbers of singles, binaries, triples, and quadruples in the sample are 12, 14, 5, and 2, respectively. The derived multiplicity frequency (MF) and companion star fraction (CSF) for Class 0 protostars are 0.64 {+-} 0.08 and 0.91 {+-} 0.05, respectively, with no correction for completeness. The derived MF and CSF in this survey are approximately two times higher than the values found in the binary surveys toward Class I young stellar objects, and approximately three (for MF) and four (for CSF) times larger than the values found among main-sequence stars, with a similar range of separations. Furthermore, the observed fraction of high-order multiple systems to binary systems in Class 0 protostars (0.50 {+-} 0.09) is also larger than the fractions found in Class I young stellar objects (0.31 {+-} 0.07) and main-sequence stars ({<=}0.2). These results suggest that binary properties evolve as protostars evolve, as predicted by numerical simulations. The distribution of separations for Class 0 protostellar binary/multiple systems shows a general trend in which CSF increases with decreasing companion separation. We find that 67% {+-} 8% of the protobinary systems have circumstellar mass ratios below 0.5, implying that unequal-mass systems are preferred in the process of binary star formation. We suggest an empirical sequential fragmentation picture for binary star formation, based on this

  6. Accretion-powered Compact Binaries

    Science.gov (United States)

    Mauche, Christopher W.

    2003-12-01

    Preface; The workshop logo; A short history of the CV workshop F. A. Córdova; Part I. Observations: 1. Low mass x-ray binaries A. P. Cowley, P. C. Schmidtke, D. Crampton, J. B. Hutchings, C. A. Haswell, E. L. Robinson, K. D. Horne, H. M. Johnston, S. R. Kulkarni, S. Kitamoto, X. Han, R. M. Hjellming, R. M. Wagner, S. L. Morris, P. Hertz, A. N. Parmar, L. Stella, P. Giommi, P. J. Callanan, T. Naylor, P. A. Charles, C. D. Bailyn, J. N. Imamura, T. Steiman-Cameron, J. Kristian, J. Middleditch, L. Angelini and J. P. Noris; 2. Nonmagnetic cataclysmic variables R. S. Polidan, C. W. Mauche, R. A. Wade, R. H. Kaitchuck, E. M. Schlegel, P. A. Hantzios, R. C. Smith, J. H. Wood, F. Hessman, A. Fiedler, D. H. P. Jones, J. Casares, P. A. Charles, J. van Paradijs, E. Harlaftis, T. Naylor, G. Sonneborn, B. J. M. Hassall, K. Horne, C. A. la Dous, A. W. Shafter, N. A. Hawkins, D. A. H. Buckley, D. J. Sullivan, F. V. Hessman, V. S. Dhillon, T. R. Marsh, J. Singh, S. Seetha, F. Giovannelli, A. Bianchini, E. M. Sion, D. J. Mullan, H. L. Shipman, G. Machin, P. J. Callanan, S. B. Howell, P. Szkody, E. M. Schlegel and R. F. Webbink; 3. Magnetic cataclysmic variables C. Hellier, K. O. Mason, C. W. Mauche, G. S. Miller, J. C. Raymond, F. K. Lamb, J. Patterson, A. J. Norton, M. G. Watson, A. R. King, I. M. McHardy, H. Lehto, J. P. Osborne, E. L. Robinson, A. W. Shafter, S. Balachandran, S. R. Rosen, J. Krautter, W. Buchholz, D. A. H. Buckley, I. R. Tuoly, D. Crampton, B. Warner, R. M. Prestage, B. N. Ashoka, M. Mouchet, J. M. Bonnet-Bidaud, J. M. Hameury, P. Szkody, P. Garnavich, S. Howell, T. Kii, M. Cropper, K. Mason, J. Bailey, D. T. Wickramasinghe, L. Ferrario, K. Beuermann, A. D. Schwope, H.-C. Thomas, S. Jordan, J. Schachter, A. V. Filippenko, S. M. Kahn, F. B. S. Paerels, K. Mukai, M. L. Edgar, S. Larsson, R. F. Jameson, A. R. King, A. Silber, R. Remillard, H. Bradt, M. Ishida, T. Ohashi and G. D. Schmidt; Part II. Accretion Theory: 4. Nonmagnetic W. Kley, F. Geyer, H. Herold, H

  7. Effects of regularity on the processing of sound omission in a tone sequence in musicians and non-musicians.

    Science.gov (United States)

    Ono, Kentaro; Matsuhashi, Masao; Mima, Tatsuya; Fukuyama, Hidenao; Altmann, Christian F

    2013-09-01

    Numerous studies have reported that perceptual grouping affects the pre-attentive processing of sound omission in a sequence of tones. However, it remains unclear whether or not the perceptual grouping and musical experience affect the attentive processing of sound omission. To this end, we created a sequence of loud (L) and soft (S) tones grouped as 'LLSLLS…' and a random sequence of the L and S tones. The omission of the L tones was inserted pseudo-randomly in the random sequence, and there were two positions at which it was inserted. For within-group omission, the omission was after the first L tone within the 'LLS' pattern. For between-group omission, the omission was inserted between the patterns. The brain response to the omission in musicians and non-musicians was measured using magnetoencephalography. During the magnetoencephalography measurement, the subjects' performance in a task to detect the omission was faster in the random sequence than in the group sequence. Source analysis showed that the omission in the random sequence caused greater activity than that in the group sequence. The increase was found in the right inferior parietal lobe in musicians, whereas it was found in the left superior temporal gyrus in non-musicians. These results suggest that the attentive processing of perceptual grouping might implicate the left superior temporal gyrus or right inferior parietal lobe, depending on musical experience. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  8. Hybrid Black-Hole Binary Initial Data

    Science.gov (United States)

    Mundim, Bruno C.; Kelly, Bernard J.; Nakano, Hiroyuki; Zlochower, Yosef; Campanelli, Manuela

    2010-01-01

    "Traditional black-hole binary puncture initial data is conformally flat. This unphysical assumption is coupled with a lack of radiation signature from the binary's past life. As a result, waveforms extracted from evolutions of this data display an abrupt jump. In Kelly et al. [Class. Quantum Grav. 27:114005 (2010)], a new binary black-hole initial data with radiation contents derived in the post-Newtonian (PN) calculations was adapted to puncture evolutions in numerical relativity. This data satisfies the constraint equations to the 2.5PN order, and contains a transverse-traceless "wavy" metric contribution, violating the standard assumption of conformal flatness. Although the evolution contained less spurious radiation, there were undesired features; the unphysical horizon mass loss and the large initial orbital eccentricity. Introducing a hybrid approach to the initial data evaluation, we significantly reduce these undesired features."

  9. Orbit of a Resolved Trojan Binary

    Science.gov (United States)

    Noll, Keith

    2017-08-01

    We have identified the Jupiter Trojan (16974) 1998 WR21 as a binary, making it only the third known resolvable binary in this population. We will use HST to determine its orbit from which we will determine the system mass. Using the mass and WISE-derived albedo, we will derive the density. Density can be used to constrain planetary migration models; low density is characteristic of bodies found in the Kuiper Belt, a remnant of the solar system's protoplanetary disk. Only one undisputed density has been measured in the Trojans, that of the binary (617) Patroclus, which has a low density of 800 kg/m3. The density of WR21 will test whether Patroclus is an anomaly or whether low densities might be the norm, as they are in the Kuiper Belt.

  10. Compact binary hashing for music retrieval

    Science.gov (United States)

    Seo, Jin S.

    2014-03-01

    With the huge volume of music clips available for protection, browsing, and indexing, there is an increased attention to retrieve the information contents of the music archives. Music-similarity computation is an essential building block for browsing, retrieval, and indexing of digital music archives. In practice, as the number of songs available for searching and indexing is increased, so the storage cost in retrieval systems is becoming a serious problem. This paper deals with the storage problem by extending the supervector concept with the binary hashing. We utilize the similarity-preserving binary embedding in generating a hash code from the supervector of each music clip. Especially we compare the performance of the various binary hashing methods for music retrieval tasks on the widely-used genre dataset and the in-house singer dataset. Through the evaluation, we find an effective way of generating hash codes for music similarity estimation which improves the retrieval performance.

  11. On binary channels to anomalous Cepheids

    Science.gov (United States)

    Gautschy, Alfred; Saio, Hideyuki

    2017-07-01

    Anomalous Cepheids are a rather rare family of pulsating variables preferably found in dwarf galaxies. Attempts to model these variable stars via single-star evolution scenarios still leave space for improvements to better grasp their origin. Focusing on the Large Magellanic Cloud with its rich population of anomalous Cepheids to compare against, we probe the role binary stars might play to understand the nature of anomalous Cepheids. The evolution of donors and accretors undergoing Case-B mass transfer along the first red giant branch as well as merger-like models was calculated. First results show that in binary scenarios, a larger range of star masses and metallicities up to Z ≲ 0.008, higher than deemed possible hitherto, enter and pass through the instability strip. If binary stars play a role in anomalous Cepheid populations, mass donors, mass accretors or even mergers are potential candidates to counteract constraints imposed by the single-star approach.

  12. INTEGRAL & RXTE View of Gamma-ray Binaries

    OpenAIRE

    Li, Jian; Torres, Diego F.; Zhang, Shu; Wang, Jianmin

    2013-01-01

    Gamma-ray binaries are X-ray binaries with gamma-ray emissions. Their multi-wavelength emissions range from radio, optical, X-ray and to very high energy (TeV). X-ray emissions are crucial to understand the nature of gamma-ray binaries. INTEGRAL and RXTE have covered and monitored most of the gamma-ray binaries in hard and soft X-rays. Here we report the results of several gamma-ray binaries and possible gamma-ray binaries from INTEGRAL and RXTE.

  13. Binary systems from quantum cluster equilibrium theory.

    Science.gov (United States)

    Brüssel, Marc; Perlt, Eva; Lehmann, Sebastian B C; von Domaros, Michael; Kirchner, Barbara

    2011-11-21

    An extension of the quantum cluster equilibrium theory to treat binary mixtures is introduced in this work. The necessary equations are derived and a possible implementation is presented. In addition an alternative sampling procedure using widely available experimental data for the quantum cluster equilibrium approach is suggested and tested. An illustrative example, namely, the binary mixture of water and dimethyl sulfoxide, is given to demonstrate the new approach. A basic cluster set is introduced containing the relevant cluster motifs. The populations computed by the quantum cluster equilibrium approach are compared to the experimental data. Furthermore, the excess Gibbs free energy is computed and compared to experiments as well.

  14. Winds from disks in compact binaries

    Energy Technology Data Exchange (ETDEWEB)

    Mauche, C.W.

    1993-10-27

    We herein present an observational and theoretical review of the winds of compact binaries. After a brief consideration of the accretion disk coronae and winds of X-ray binaries, the review concentrates on the winds of cataclysmic variables (CVs). Specifically, we consider the related problems of the geometry and mass-loss rate of the winds of CVs, their ionization state and variability, and the results from studies of eclipsing CVs. Finally, the properties of bona fide accretion disk wind models are reviewed.

  15. Non-binary or genderqueer genders

    OpenAIRE

    Richards, Christina; Bouman, Walter Pierre; Seal, Leighton; Barker, Meg John; Nieder, Timo O.; T'Sjoen, Guy

    2016-01-01

    Some people have a gender which is neither male nor female and may identify as both male and female at one time, as different genders at different times, as no gender at all, or dispute the very idea of only two genders. The umbrella terms for such genders are genderqueer' or non-binary' genders. Such gender identities outside of the binary of female and male are increasingly being recognized in legal, medical and psychological systems and diagnostic classifications in line with the emerging ...

  16. Binary Sparse Phase Retrieval via Simulated Annealing

    Directory of Open Access Journals (Sweden)

    Wei Peng

    2016-01-01

    Full Text Available This paper presents the Simulated Annealing Sparse PhAse Recovery (SASPAR algorithm for reconstructing sparse binary signals from their phaseless magnitudes of the Fourier transform. The greedy strategy version is also proposed for a comparison, which is a parameter-free algorithm. Sufficient numeric simulations indicate that our method is quite effective and suggest the binary model is robust. The SASPAR algorithm seems competitive to the existing methods for its efficiency and high recovery rate even with fewer Fourier measurements.

  17. Binary Ni-Nb bulk metallic glasses

    Science.gov (United States)

    Xia, L.; Li, W. H.; Fang, S. S.; Wei, B. C.; Dong, Y. D.

    2006-01-01

    We studied the glass forming ability of Ni-Nb binary alloys and found that some of the alloys can be prepared into bulk metallic glasses by a conventional Cu-mold casting. The best glass former within the compositional range studied is off-eutectic Ni62Nb38 alloy, which is markedly different from those predicted by the multicomponent and deep eutectic rules. The glass formation mechanism for binary Ni-Nb alloys was studied from the thermodynamic point of view and a parameter γ* was proposed to approach the ability of glass formation against crystallization.

  18. Inducing Risk Neutral Preferences with Binary Lotteries

    DEFF Research Database (Denmark)

    Harrison, Glenn W.; Martínez-Correa, Jimmy; Swarthout, J. Todd

    2013-01-01

    We evaluate the binary lottery procedure for inducing risk neutral behavior. We strip the experimental implementation down to bare bones, taking care to avoid any potentially confounding assumptions about behavior having to be made. In particular, our evaluation does not rely on the assumed...... validity of any strategic equilibrium behavior, or even the customary independence axiom. We show that subjects sampled from our population are generally risk averse when lotteries are defined over monetary outcomes, and that the binary lottery procedure does indeed induce a statistically significant shift...... toward risk neutrality. This striking result generalizes to the case in which subjects make several lottery choices and one is selected for payment....

  19. Testing the Binary Black Hole Nature of a Compact Binary Coalescence

    Science.gov (United States)

    Krishnendu, N. V.; Arun, K. G.; Mishra, Chandra Kant

    2017-09-01

    We propose a novel method to test the binary black hole nature of compact binaries detectable by gravitational wave (GW) interferometers and, hence, constrain the parameter space of other exotic compact objects. The spirit of the test lies in the "no-hair" conjecture for black holes where all properties of a Kerr black hole are characterized by its mass and spin. The method relies on observationally measuring the quadrupole moments of the compact binary constituents induced due to their spins. If the compact object is a Kerr black hole (BH), its quadrupole moment is expressible solely in terms of its mass and spin. Otherwise, the quadrupole moment can depend on additional parameters (such as the equation of state of the object). The higher order spin effects in phase and amplitude of a gravitational waveform, which explicitly contains the spin-induced quadrupole moments of compact objects, hence, uniquely encode the nature of the compact binary. Thus, we argue that an independent measurement of the spin-induced quadrupole moment of the compact binaries from GW observations can provide a unique way to distinguish binary BH systems from binaries consisting of exotic compact objects.

  20. Testing the Binary Black Hole Nature of a Compact Binary Coalescence.

    Science.gov (United States)

    Krishnendu, N V; Arun, K G; Mishra, Chandra Kant

    2017-09-01

    We propose a novel method to test the binary black hole nature of compact binaries detectable by gravitational wave (GW) interferometers and, hence, constrain the parameter space of other exotic compact objects. The spirit of the test lies in the "no-hair" conjecture for black holes where all properties of a Kerr black hole are characterized by its mass and spin. The method relies on observationally measuring the quadrupole moments of the compact binary constituents induced due to their spins. If the compact object is a Kerr black hole (BH), its quadrupole moment is expressible solely in terms of its mass and spin. Otherwise, the quadrupole moment can depend on additional parameters (such as the equation of state of the object). The higher order spin effects in phase and amplitude of a gravitational waveform, which explicitly contains the spin-induced quadrupole moments of compact objects, hence, uniquely encode the nature of the compact binary. Thus, we argue that an independent measurement of the spin-induced quadrupole moment of the compact binaries from GW observations can provide a unique way to distinguish binary BH systems from binaries consisting of exotic compact objects.

  1. Neutron-Star-Black-Hole Binaries Produced by Binary-Driven Hypernovae.

    Science.gov (United States)

    Fryer, Chris L; Oliveira, F G; Rueda, J A; Ruffini, R

    2015-12-04

    Binary-driven hypernovae (BdHNe) within the induced gravitational collapse paradigm have been introduced to explain energetic (E_{iso}≳10^{52}  erg), long gamma-ray bursts (GRBs) associated with type Ic supernovae (SNe). The progenitor is a tight binary composed of a carbon-oxygen (CO) core and a neutron-star (NS) companion, a subclass of the newly proposed "ultrastripped" binaries. The CO-NS short-period orbit causes the NS to accrete appreciable matter from the SN ejecta when the CO core collapses, ultimately causing it to collapse to a black hole (BH) and producing a GRB. These tight binaries evolve through the SN explosion very differently than compact binaries studied in population synthesis calculations. First, the hypercritical accretion onto the NS companion alters both the mass and the momentum of the binary. Second, because the explosion time scale is on par with the orbital period, the mass ejection cannot be assumed to be instantaneous. This dramatically affects the post-SN fate of the binary. Finally, the bow shock created as the accreting NS plows through the SN ejecta transfers angular momentum, braking the orbit. These systems remain bound even if a large fraction of the binary mass is lost in the explosion (well above the canonical 50% limit), and even large kicks are unlikely to unbind the system. Indeed, BdHNe produce a new family of NS-BH binaries unaccounted for in current population synthesis analyses and, although they may be rare, the fact that nearly 100% remain bound implies that they may play an important role in the compact merger rate, important for gravitational waves that, in turn, can produce a new class of ultrashort GRBs.

  2. BROWN DWARF BINARIES FROM DISINTEGRATING TRIPLE SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Reipurth, Bo [Institute for Astronomy and NASA Astrobiology Institute University of Hawaii, 640 N. Aohoku Place, Hilo, HI 96720 (United States); Mikkola, Seppo, E-mail: reipurth@ifa.hawaii.edu, E-mail: Seppo.Mikkola@utu.fi [Tuorla Observatory, University of Turku, Väisäläntie 20, Piikkiö (Finland)

    2015-04-15

    Binaries in which both components are brown dwarfs (BDs) are being discovered at an increasing rate, and their properties may hold clues to their origin. We have carried out 200,000 N-body simulations of three identical stellar embryos with masses drawn from a Chabrier IMF and embedded in a molecular core. The bodies are initially non-hierarchical and undergo chaotic motions within the cloud core, while accreting using Bondi–Hoyle accretion. The coupling of dynamics and accretion often leads to one or two dominant bodies controlling the center of the cloud core, while banishing the other(s) to the lower-density outskirts, leading to stunted growth. Eventually each system transforms either to a bound hierarchical configuration or breaks apart into separate single and binary components. The orbital motion is followed for 100 Myr. In order to illustrate 200,000 end-states of such dynamical evolution with accretion, we introduce the “triple diagnostic diagram,” which plots two dimensionless numbers against each other, representing the binary mass ratio and the mass ratio of the third body to the total system mass. Numerous freefloating BD binaries are formed in these simulations, and statistical properties are derived. The separation distribution function is in good correspondence with observations, showing a steep rise at close separations, peaking around 13 AU and declining more gently, reaching zero at separations greater than 200 AU. Unresolved BD triple systems may appear as wider BD binaries. Mass ratios are strongly peaked toward unity, as observed, but this is partially due to the initial assumptions. Eccentricities gradually increase toward higher values, due to the lack of viscous interactions in the simulations, which would both shrink the orbits and decrease their eccentricities. Most newborn triple systems are unstable and while there are 9209 ejected BD binaries at 1 Myr, corresponding to about 4% of the 200,000 simulations, this number has grown to

  3. The Tarantula Massive Binary Monitoring. I. Observational campaign and OB-type spectroscopic binaries

    Science.gov (United States)

    Almeida, L. A.; Sana, H.; Taylor, W.; Barbá, R.; Bonanos, A. Z.; Crowther, P.; Damineli, A.; de Koter, A.; de Mink, S. E.; Evans, C. J.; Gieles, M.; Grin, N. J.; Hénault-Brunet, V.; Langer, N.; Lennon, D.; Lockwood, S.; Maíz Apellániz, J.; Moffat, A. F. J.; Neijssel, C.; Norman, C.; Ramírez-Agudelo, O. H.; Richardson, N. D.; Schootemeijer, A.; Shenar, T.; Soszyński, I.; Tramper, F.; Vink, J. S.

    2017-02-01

    Context. Massive binaries play a crucial role in the Universe. Knowing the distributions of their orbital parameters is important for a wide range of topics from stellar feedback to binary evolution channels and from the distribution of supernova types to gravitational wave progenitors, yet no direct measurements exist outside the Milky Way. Aims: The Tarantula Massive Binary Monitoring project was designed to help fill this gap by obtaining multi-epoch radial velocity (RV) monitoring of 102 massive binaries in the 30 Doradus region. Methods: In this paper we analyze 32 FLAMES/GIRAFFE observations of 93 O- and 7 B-type binaries. We performed a Fourier analysis and obtained orbital solutions for 82 systems: 51 single-lined (SB1) and 31 double-lined (SB2) spectroscopic binaries. Results: Overall, the binary fraction and orbital properties across the 30 Doradus region are found to be similar to existing Galactic samples. This indicates that within these domains environmental effects are of second order in shaping the properties of massive binary systems. A small difference is found in the distribution of orbital periods, which is slightly flatter (in log space) in 30 Doradus than in the Galaxy, although this may be compatible within error estimates and differences in the fitting methodology. Also, orbital periods in 30 Doradus can be as short as 1.1 d, somewhat shorter than seen in Galactic samples. Equal mass binaries (q> 0.95) in 30 Doradus are all found outside NGC 2070, the central association that surrounds R136a, the very young and massive cluster at 30 Doradus's core. Most of the differences, albeit small, are compatible with expectations from binary evolution. One outstanding exception, however, is the fact that earlier spectral types (O2-O7) tend to have shorter orbital periods than later spectral types (O9.2-O9.7). Conclusions: Our results point to a relative universality of the incidence rate of massive binaries and their orbital properties in the

  4. Main: Sequences [KOME

    Lifescience Database Archive (English)

    Full Text Available Sequences Nucleotide Sequence Nucleotide sequence of full length cDNA (trimmed sequence) kome_ine_full_se...quence_db.fasta.zip kome_ine_full_sequence_db.zip kome_ine_full_sequence_db ...

  5. Spin frequency distributions of binary millisecond pulsars

    NARCIS (Netherlands)

    Papitto, A.; Torres, D.F.; Rea, N.; Tauris, T.M.

    2014-01-01

    Rotation-powered millisecond radio pulsars have been spun up to their present spin period by a 108−109 yr long X-ray-bright phase of accretion of matter and angular momentum in a low-to-intermediate mass binary system. Recently, the discovery of transitional pulsars that alternate cyclically between

  6. Strong lensing interferometry for compact binaries

    NARCIS (Netherlands)

    Pen, U.L.; Yang, I.S.

    2015-01-01

    We propose a possibility to improve the current precision measurements on compact binaries. When the orbital axis is almost perpendicular to our line of sight, a pulsar behind its companion can form two strong lensing images. These images cannot be resolved, but we can use multiwavelength

  7. Binary translation using peephole translation rules

    Science.gov (United States)

    Bansal, Sorav; Aiken, Alex

    2010-05-04

    An efficient binary translator uses peephole translation rules to directly translate executable code from one instruction set to another. In a preferred embodiment, the translation rules are generated using superoptimization techniques that enable the translator to automatically learn translation rules for translating code from the source to target instruction set architecture.

  8. Predicting Social Trust with Binary Logistic Regression

    Science.gov (United States)

    Adwere-Boamah, Joseph; Hufstedler, Shirley

    2015-01-01

    This study used binary logistic regression to predict social trust with five demographic variables from a national sample of adult individuals who participated in The General Social Survey (GSS) in 2012. The five predictor variables were respondents' highest degree earned, race, sex, general happiness and the importance of personally assisting…

  9. Performance of binary FSK data transmission systems

    Science.gov (United States)

    Batson, B. H.

    1973-01-01

    Matched-filter detection of binary signals is discussed in terms of the probability of bit error. The equations for the probability of error are derived for coherent phase shift keying, and coherent frequency shift keying (FSK). Suboptimum detection of FSK signals is also discussed for discriminators.

  10. Binary alloys for refractory-metal brazing

    Science.gov (United States)

    Morris, J. F.

    1974-01-01

    Data on binary-metal eutectics and melting-point minimums have been assembled for use in selecting brazing filler compositions for refractory metals. Data are presented in four tables for ready reference. Brief discussion of problems and potentials of metallides is included in appendix.

  11. A binary main-belt comet

    Science.gov (United States)

    Agarwal, Jessica; Jewitt, David; Mutchler, Max; Weaver, Harold; Larson, Stephen

    2017-09-01

    Asteroids are primitive Solar System bodies that evolve both collisionally and through disruptions arising from rapid rotation. These processes can lead to the formation of binary asteroids and to the release of dust, both directly and, in some cases, through uncovering frozen volatiles. In a subset of the asteroids called main-belt comets, the sublimation of excavated volatiles causes transient comet-like activity. Torques exerted by sublimation measurably influence the spin rates of active comets and might lead to the splitting of bilobate comet nuclei. The kilometre-sized main-belt asteroid 288P (300163) showed activity for several months around its perihelion 2011 (ref. 11), suspected to be sustained by the sublimation of water ice and supported by rapid rotation, while at least one component rotates slowly with a period of 16 hours (ref. 14). The object 288P is part of a young family of at least 11 asteroids that formed from a precursor about 10 kilometres in diameter during a shattering collision 7.5 million years ago. Here we report that 288P is a binary main-belt comet. It is different from the known asteroid binaries in its combination of wide separation, near-equal component size, high eccentricity and comet-like activity. The observations also provide strong support for sublimation as the driver of activity in 288P and show that sublimation torques may play an important part in binary orbit evolution.

  12. Flip-flopping binary black holes.

    Science.gov (United States)

    Lousto, Carlos O; Healy, James

    2015-04-10

    We study binary spinning black holes to display the long term individual spin dynamics. We perform a full numerical simulation starting at an initial proper separation of d≈25M between equal mass holes and evolve them down to merger for nearly 48 orbits, 3 precession cycles, and half of a flip-flop cycle. The simulation lasts for t=20 000M and displays a total change in the orientation of the spin of one of the black holes from an initial alignment with the orbital angular momentum to a complete antialignment after half of a flip-flop cycle. We compare this evolution with an integration of the 3.5 post-Newtonian equations of motion and spin evolution to show that this process continuously flip flops the spin during the lifetime of the binary until merger. We also provide lower order analytic expressions for the maximum flip-flop angle and frequency. We discuss the effects this dynamics may have on spin growth in accreting binaries and on the observational consequences for galactic and supermassive binary black holes.

  13. Cluster selection in binary nuclear models

    CERN Document Server

    Buck, B; Pérez, S M

    2000-01-01

    We present a simple prescription for selecting the cluster and core in a binary cluster-model description of a nucleus. The prescription reproduces the cluster-core combinations used in earlier successful applications of the model, predicts others, and extends the good agreement previously found with observed B(E2; 2 sup + -> 0 sup +) values of actinide nuclei. Refs. 31 (author)

  14. Receptive fields selection for binary feature description.

    Science.gov (United States)

    Fan, Bin; Kong, Qingqun; Trzcinski, Tomasz; Wang, Zhiheng; Pan, Chunhong; Fua, Pascal

    2014-06-01

    Feature description for local image patch is widely used in computer vision. While the conventional way to design local descriptor is based on expert experience and knowledge, learning-based methods for designing local descriptor become more and more popular because of their good performance and data-driven property. This paper proposes a novel data-driven method for designing binary feature descriptor, which we call receptive fields descriptor (RFD). Technically, RFD is constructed by thresholding responses of a set of receptive fields, which are selected from a large number of candidates according to their distinctiveness and correlations in a greedy way. Using two different kinds of receptive fields (namely rectangular pooling area and Gaussian pooling area) for selection, we obtain two binary descriptors RFDR and RFDG .accordingly. Image matching experiments on the well-known patch data set and Oxford data set demonstrate that RFD significantly outperforms the state-of-the-art binary descriptors, and is comparable with the best float-valued descriptors at a fraction of processing time. Finally, experiments on object recognition tasks confirm that both RFDR and RFDG successfully bridge the performance gap between binary descriptors and their floating-point competitors.

  15. The average size of ordered binary subgraphs

    NARCIS (Netherlands)

    van Leeuwen, J.; Hartel, Pieter H.

    To analyse the demands made on the garbage collector in a graph reduction system, the change in size of an average graph is studied when an arbitrary edge is removed. In ordered binary trees the average number of deleted nodes as a result of cutting a single edge is equal to the average size of a

  16. Non-binary or genderqueer genders.

    Science.gov (United States)

    Richards, Christina; Bouman, Walter Pierre; Seal, Leighton; Barker, Meg John; Nieder, Timo O; T'Sjoen, Guy

    2016-01-01

    Some people have a gender which is neither male nor female and may identify as both male and female at one time, as different genders at different times, as no gender at all, or dispute the very idea of only two genders. The umbrella terms for such genders are 'genderqueer' or 'non-binary' genders. Such gender identities outside of the binary of female and male are increasingly being recognized in legal, medical and psychological systems and diagnostic classifications in line with the emerging presence and advocacy of these groups of people. Population-based studies show a small percentage--but a sizable proportion in terms of raw numbers--of people who identify as non-binary. While such genders have been extant historically and globally, they remain marginalized, and as such--while not being disorders or pathological in themselves--people with such genders remain at risk of victimization and of minority or marginalization stress as a result of discrimination. This paper therefore reviews the limited literature on this field and considers ways in which (mental) health professionals may assist the people with genderqueer and non-binary gender identities and/or expressions they may see in their practice. Treatment options and associated risks are discussed.

  17. Relativistic calculations of coalescing binary neutron stars

    Indian Academy of Sciences (India)

    Relativistic calculations of coalescing binary neutron stars. JOSHUA FABER, PHILIPPE GRANDCLÉMENT and FREDERIC RASIO. Department of Physics and Astronomy, Northwestern University, Evanston,. IL 60208-0834, USA. E-mail: rasio@mac.com. Abstract. We have designed and tested a new relativistic Lagrangian ...

  18. The Kepler Mission and Eclipsing Binaries

    Science.gov (United States)

    2006-01-01

    exoplanets , differential photometry, eclipsing binaries 1. Introduction The Kepler Mission is NASA’s first mission capable of detecting Earth-size and...a star where liquid water can exist on the surface of a 236 Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden for the

  19. Binary Options as a Modern Fenomenon of Financial Business

    National Research Council Canada - National Science Library

    Andrea Kolková; Lucie Lenertová

    2016-01-01

    Binary options are a new instrument of the financial market. The aim of this paper is to analyze the use of binary options with trading and to illustrate this on the practical example of trades based on Bollinger bands indicator...

  20. Merging Galaxies Create a Binary Quasar

    Science.gov (United States)

    2010-02-01

    Astronomers have found the first clear evidence of a binary quasar within a pair of actively merging galaxies. Quasars are the extremely bright centers of galaxies surrounding super-massive black holes, and binary quasars are pairs of quasars bound together by gravity. Binary quasars, like other quasars, are thought to be the product of galaxy mergers. Until now, however, binary quasars have not been seen in galaxies that are unambiguously in the act of merging. But images of a new binary quasar from the Carnegie Institution's Magellan telescope in Chile show two distinct galaxies with "tails" produced by tidal forces from their mutual gravitational attraction. "This is really the first case in which you see two separate galaxies, both with quasars, that are clearly interacting," says Carnegie astronomer John Mulchaey who made observations crucial to understanding the galaxy merger. Most, if not all, large galaxies, such as our galaxy the Milky Way, host super-massive black holes at their centers. Because galaxies regularly interact and merge, astronomers have assumed that binary super-massive black holes have been common in the Universe, especially during its early history. Black holes can only be detected as quasars when they are actively accreting matter, a process that releases vast amounts of energy. A leading theory is that galaxy mergers trigger accretion, creating quasars in both galaxies. Because most such mergers would have happened in the distant past, binary quasars and their associated galaxies are very far away and therefore difficult for most telescopes to resolve. The binary quasar, labeled SDSS J1254+0846, was initially detected by the Sloan Digital Sky Survey, a large scale astronomical survey of galaxies and over 120,000 quasars. Further observations by Paul Green of the Harvard-Smithsonian Center for Astrophysics and colleagues* using NASA's Chandra's X-ray Observatory and telescopes at Kitt Peak National Observatory in Arizona and Palomar

  1. Probabilistic seismic history matching using binary images

    Science.gov (United States)

    Davolio, Alessandra; Schiozer, Denis Jose

    2018-02-01

    Currently, the goal of history-matching procedures is not only to provide a model matching any observed data but also to generate multiple matched models to properly handle uncertainties. One such approach is a probabilistic history-matching methodology based on the discrete Latin Hypercube sampling algorithm, proposed in previous works, which was particularly efficient for matching well data (production rates and pressure). 4D seismic (4DS) data have been increasingly included into history-matching procedures. A key issue in seismic history matching (SHM) is to transfer data into a common domain: impedance, amplitude or pressure, and saturation. In any case, seismic inversions and/or modeling are required, which can be time consuming. An alternative to avoid these procedures is using binary images in SHM as they allow the shape, rather than the physical values, of observed anomalies to be matched. This work presents the incorporation of binary images in SHM within the aforementioned probabilistic history matching. The application was performed with real data from a segment of the Norne benchmark case that presents strong 4D anomalies, including softening signals due to pressure build up. The binary images are used to match the pressurized zones observed in time-lapse data. Three history matchings were conducted using: only well data, well and 4DS data, and only 4DS. The methodology is very flexible and successfully utilized the addition of binary images for seismic objective functions. Results proved the good convergence of the method in few iterations for all three cases. The matched models of the first two cases provided the best results, with similar well matching quality. The second case provided models presenting pore pressure changes according to the expected dynamic behavior (pressurized zones) observed on 4DS data. The use of binary images in SHM is relatively new with few examples in the literature. This work enriches this discussion by presenting a new

  2. Hafnium binary alloys from experiments and first principles

    OpenAIRE

    Levy, Ohad; Hart, Gus L. W.; Curtarolo, Stefano

    2009-01-01

    Despite the increasing importance of hafnium in numerous technological applications, experimental and computational data on its binary alloys is sparse. In particular, data is scant on those binary systems believed to be phase separating. We performed a comprehensive study of 44 hafnium binary systems with alkali metals, alkaline earths, transition metals and metals, using high-throughput first principles calculations. These computations predict novel unsuspected compounds in six binary syste...

  3. Planetary Formation and Dynamics in Binary Systems

    Science.gov (United States)

    Xie, J. W.

    2013-01-01

    As of today, over 500 exoplanets have been detected since the first exoplanet was discovered around a solar-like star in 1995. The planets in binaries could be common as stars are usually born in binary or multiple star systems. Although current observations show that the planet host rate in multiple star systems is around 17%, this fraction should be considered as a lower limit because of noticeable selection effects against binaries in planet searches. Most of the current known planet-bearing binary systems are S-types, meaning the companion star acts as a distant satellite, typically orbiting the inner star-planet system over 100 AU away. Nevertheless, there are four systems with a smaller separation of 20 AU, including the Gamma Cephei, GJ 86, HD 41004, and HD 196885. In addition to the planets in circumprimary (S-type) orbits discussed above, planets in circumbinary (P-type) orbits have been found in only two systems. In this thesis, we mainly study the planet formation in the S-type binary systems. In chapter 1, we first summarize current observational facts of exoplanets both in single-star and binary systems, then review the theoretical models of planet formation, with special attention to the application in binary systems. Perturbative effects from stellar companions render the planet formation process in binary systems even more complex than that in single-star systems. The perturbations from a binary companion can excite planetesimal orbits, and increase their mutual impact velocities to the values that might exceed their escape velocity or even the critical velocity for the onset of eroding collisions. The intermediate stage of the formation process---from planetesimals to planetary embryos---is thus the most problematic. In the following chapters, we investigate whether and how the planet formation goes through such a problematic stage. In chapter 2, we study the effects of gas dissipation on the planetesimals' mutual accretion. We find that in a

  4. Neutron Stars in X-ray Binaries and their Environments

    Indian Academy of Sciences (India)

    Biswajit Paul

    2017-09-07

    Sep 7, 2017 ... Abstract. Neutron stars in X-ray binary systems are fascinating objects that display a wide range of timing and spectral phenomena in the X-rays. Not only parameters of the neutron stars, like magnetic field strength and spin period evolve in their active binary phase, the neutron stars also affect the binary ...

  5. Microlensing Binaries Discovered through High-magnification Channel

    DEFF Research Database (Denmark)

    Shin, I.-G.; Choi, J.-Y.; Park, S.-Y.

    2012-01-01

    Microlensing can provide a useful tool to probe binary distributions down to low-mass limits of binary companions. In this paper, we analyze the light curves of eight binary-lensing events detected through the channel of high-magnification events during the seasons from 2007 to 2010. The perturba...

  6. Beyond the Binary: Dexterous Teaching and Knowing in Mathematics Education

    Science.gov (United States)

    Adam, Raoul; Chigeza, Philemon

    2015-01-01

    This paper identifies binary oppositions in the discourse of mathematics education and introduces a binary-epistemic model for (re)conceptualising these oppositions and the epistemic-pedagogic problems they represent. The model is attentive to the contextual relationships between pedagogically relevant binaries (e.g., traditional/progressive,…

  7. The Formation of Contact and Very Close Binaries

    Energy Technology Data Exchange (ETDEWEB)

    Kisseleva-Eggleton, L; Eggleton, P P

    2007-08-10

    We explore the possibility that all close binaries, i.e. those with periods {approx}< 3 d, including contact (W UMa) binaries, are produced from initially wider binaries (periods of say 10's of days) by the action of a triple companion through the medium of Kozai Cycles with Tidal Friction (KCTF).

  8. Compact stars and the evolution of binary systems

    NARCIS (Netherlands)

    van den Heuvel, E.P.J.

    2011-01-01

    The Chandrasekhar limit is of key importance for the evolution of white dwarfs in binary systems and for the formation of neutron stars and black holes in binaries. Mass transfer can drive a white dwarf in a binary over the Chandrasekhar limit, which may lead to a Type Ia supernova (in case of a CO

  9. A decoding method of an n length binary BCH code through (n + 1n length binary cyclic code

    Directory of Open Access Journals (Sweden)

    TARIQ SHAH

    2013-09-01

    Full Text Available For a given binary BCH code Cn of length n = 2 s - 1 generated by a polynomial of degree r there is no binary BCH code of length (n + 1n generated by a generalized polynomial of degree 2r. However, it does exist a binary cyclic code C (n+1n of length (n + 1n such that the binary BCH code Cn is embedded in C (n+1n . Accordingly a high code rate is attained through a binary cyclic code C (n+1n for a binary BCH code Cn . Furthermore, an algorithm proposed facilitates in a decoding of a binary BCH code Cn through the decoding of a binary cyclic code C (n+1n , while the codes Cn and C (n+1n have the same minimum hamming distance.

  10. High-affinity single-domain binding proteins with a binary-code interface.

    Science.gov (United States)

    Koide, Akiko; Gilbreth, Ryan N; Esaki, Kaori; Tereshko, Valentina; Koide, Shohei

    2007-04-17

    High degrees of sequence and conformation complexity found in natural protein interaction interfaces are generally considered essential for achieving tight and specific interactions. However, it has been demonstrated that specific antibodies can be built by using an interface with a binary code consisting of only Tyr and Ser. This surprising result might be attributed to yet undefined properties of the antibody scaffold that uniquely enhance its capacity for target binding. In this work we tested the generality of the binary-code interface by engineering binding proteins based on a single-domain scaffold. We show that Tyr/Ser binary-code interfaces consisting of only 15-20 positions within a fibronectin type III domain (FN3; 95 residues) are capable of producing specific binding proteins (termed "monobodies") with a low-nanomolar K(d). A 2.35-A x-ray crystal structure of a monobody in complex with its target, maltose-binding protein, and mutation analysis revealed dominant contributions of Tyr residues to binding as well as striking molecular mimicry of a maltose-binding protein substrate, beta-cyclodextrin, by the Tyr/Ser binary interface. This work suggests that an interaction interface with low chemical diversity but with significant conformational diversity is generally sufficient for tight and specific molecular recognition, providing fundamental insights into factors governing protein-protein interactions.

  11. TOPPE: A framework for rapid prototyping of MR pulse sequences.

    Science.gov (United States)

    Nielsen, Jon-Fredrik; Noll, Douglas C

    2017-11-02

    To introduce a framework for rapid prototyping of MR pulse sequences. We propose a simple file format, called "TOPPE", for specifying all details of an MR imaging experiment, such as gradient and radiofrequency waveforms and the complete scan loop. In addition, we provide a TOPPE file "interpreter" for GE scanners, which is a binary executable that loads TOPPE files and executes the sequence on the scanner. We also provide MATLAB scripts for reading and writing TOPPE files and previewing the sequence prior to hardware execution. With this setup, the task of the pulse sequence programmer is reduced to creating TOPPE files, eliminating the need for hardware-specific programming. No sequence-specific compilation is necessary; the interpreter only needs to be compiled once (for every scanner software upgrade). We demonstrate TOPPE in three different applications: k-space mapping, non-Cartesian PRESTO whole-brain dynamic imaging, and myelin mapping in the brain using inhomogeneous magnetization transfer. We successfully implemented and executed the three example sequences. By simply changing the various TOPPE sequence files, a single binary executable (interpreter) was used to execute several different sequences. The TOPPE file format is a complete specification of an MR imaging experiment, based on arbitrary sequences of a (typically small) number of unique modules. Along with the GE interpreter, TOPPE comprises a modular and flexible platform for rapid prototyping of new pulse sequences. Magn Reson Med, 2017. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  12. Mass transfer in asymptotic-giant-branch binary systems

    Science.gov (United States)

    Chen, Zhuo; Frank, Adam; Blackman, Eric G.; Nordhaus, Jason; Carroll-Nellenback, Jonathan

    2017-10-01

    Binary stars can interact via mass transfer when one member (the primary) ascends onto a giant branch. The amount of gas ejected by the binary and the amount of gas accreted by the secondary over the lifetime of the primary influence the subsequent binary phenomenology. Some of the gas ejected by the binary will remain gravitationally bound and its distribution will be closely related to the formation of planetary nebulae. We investigate the nature of mass transfer in binary systems containing an AGB star by adding radiative transfer to the AstroBEAR AMR Hydro/MHD code.

  13. The Age of Upper Scorpius from Eclipsing Binaries

    Science.gov (United States)

    David, Trevor; Hillenbrand, Lynne

    2018-01-01

    The Upper Scorpius OB association is the nearest region of recent massive star formation and thus an important benchmark for investigations concerning astrophysical timescales. Classical estimates of the association age based on the kinematics of high-mass members and a Hertzsprung-Russell (H-R) diagram of the full stellar population established an age of 5 Myr. However, recent analyses based on the H-R diagram for intermediate- and high-mass members suggest an older age of 11 Myr. Importantly, the H-R diagram ages of stars in Upper Scorpius (and other clusters of a similar age) are mass-dependent, such that low-mass members appear younger than their high-mass counterparts. Here we report an age that is self-consistent in the mass range of 0.3–5 M⊙, and based on the fundamentally-determined masses and radii of eclipsing binaries (EBs). We present nine EBs in Upper Scorpius, four of which are newly reported here and all of which were discovered from K2 photometry. Joint fitting of the eclipse photometry and radial velocities from newly acquired Keck-I/HIRES spectra yields precise masses and radii for those systems that are spectroscopically double-lined. We identify one of the EB components as a slowly pulsating B-star. We use these EBs to develop an empirical mass-radius relation for pre-main-sequence stars, and to evaluate the predictions of widely-used stellar evolutionary models. Our results are consistent with previous studies that indicate most models underestimate the masses of low-mass stars by tens of percent based on H-R diagram analyses. Models including the effects of magnetic fields produce better agreement between the observed bulk and radiative parameters of these young, low-mass stars. From the orbital elements and photometrically inferred rotation periods, we consider the dynamical states of several binaries and compare with expectations from tidal dissipation theories.

  14. Data transmission system with encryption by chaotic sequences

    Directory of Open Access Journals (Sweden)

    Politans’kyy R. L.

    2014-06-01

    Full Text Available Protection of transferable information in the telecommunication systems is possible by its imposition of coding sequence on a plaintext. Encryption of pseudorandom sequences can be performed by using generation algorithms which are implemented on the basis of the phenomenon of dynamical chaos, which is sensitive to changes in the initial conditions. One of the major problems encountered in the construction of secure communication systems is to provide synchronization between the receiving and transmitting parties of communication systems. Improvement of methods of hidden data transfer based on the systems with chaotic synchronization is the important task of research in the field of information and telecommunication systems based on chaos. This article shows an implementation of a data transmission system, encrypted by sequences, generated on the basis of one-dimensional discrete chaotic maps with ensuring synchronization of the transmitting and receiving sides of the system. In this system realization of synchronization is offered by a transmission through certain time domains of current value of xn generated by a logistic reflection. Xn transmission period depends on computer speed and distance between subscribers of the system. Its value is determined by transmitting a test message before the session. Infallible reception of test message indicates the optimal choice of a transmission period of the current value of xn. Selection period is done at the program level. For the construction of communication network modern software was used, in particular programming language Delphi 7.0. The work of the system is shown on the example of information transmission between the users of the system. The system operates in real time full duplex mode at any hardware implementation of Internet access. It is enough for the users of the system to specify IP address only.

  15. Induced Ellipticity for Inspiraling Binary Systems

    Science.gov (United States)

    Randall, Lisa; Xianyu, Zhong-Zhi

    2018-01-01

    Although gravitational waves tend to erase eccentricity of an inspiraling binary system, ellipticity can be generated in the presence of surrounding matter. We present a semianalytical method for understanding the eccentricity distribution of binary black holes (BHs) in the presence of a supermassive BH in a galactic center. Given a matter distribution, we show how to determine the resultant eccentricity analytically in the presence of both tidal forces and evaporation up to one cutoff and one matter-distribution-independent function, paving the way for understanding the environment of detected inspiraling BHs. We furthermore generalize Kozai–Lidov dynamics to situations where perturbation theory breaks down for short time intervals, allowing more general angular momentum exchange, such that eccentricity is generated even when all bodies orbit in the same plane.

  16. Binary Fingerprints at Fluctuation-Enhanced Sensing

    CERN Document Server

    Chang, Hung-Chih; King, Maria D; Kwan, Chiman

    2009-01-01

    We developed a simple way to generate binary patterns based on spectral slopes in different frequency ranges at fluctuation-enhanced sensing. Such patterns can be considered as binary "fingerprints" of odors. The method has experimentally been demonstrated with a commercial semiconducting metal oxide (Taguchi) sensor exposed to bacterial odors (Escherichia coli and Anthrax-surrogate Bacillus subtilis) and processing their stochastic signals. With a single Taguchi sensor, the situations of empty chamber, tryptic soy agar (TSA) medium, or TSA with bacteria could be distinguished with 100% reproducibility. The bacterium numbers were in the range of 25 thousands to 1 million. To illustrate the relevance for ultra-low power consumption, we show that this new type of signal processing and pattern recognition task can be implemented by a simple analog circuitry and a few logic gates with total power consumption in the microWatts range.

  17. Stellivore extraterrestrials? Binary stars as living systems

    Science.gov (United States)

    Vidal, Clément

    2016-11-01

    We lack signs of extraterrestrial intelligence (ETI) despite decades of observation in the whole electromagnetic spectrum. Could evidence be buried in existing data? To recognize ETI, we first propose criteria discerning life from non-life based on thermodynamics and living systems theory. Then we extrapolate civilizational development to both external and internal growth. Taken together, these two trends lead to an argument that some existing binary stars might actually be ETI. Since these hypothetical beings feed actively on stars, we call them "stellivores". I present an independent thermodynamic argument for their existence, with a metabolic interpretation of interacting binary stars. The jury is still out, but the hypothesis is empirically testable with existing astrophysical data.

  18. Component Properties of T Tauri Star Binaries

    Science.gov (United States)

    Muzzio, Ryan; L. Prato, T. Allen, N. Wright-Garba, L. Biddle, J. McLane (Lowell Observatory), G. Schaefer (GSU & CHARA)

    2016-01-01

    This poster describes our study of the properties of individual components of young T Tauri binary stars. We observed about 100 multi-star systems in the near-infrared, within the relatively close star forming regions Taurus and Ophiuchus. Here we specifically focus on four systems in the Taurus sample, IS Tau, UZ Tau B, IW Tau, and Haro 6- 37 A. Their spectra were taken with the Keck 2 telescope's NIRSPEC spectrograph and the imaging data with the Keck 2 NIRC2 camera, both with adaptive optics. Properties that we determined include spectral type, radial velocity, vsini, veiling, and near-infrared colors. On the basis of these data, we estimate stellar and circumstellar disk properties for the subset of binaries presented here.

  19. Kilonova Counterparts of Binary Neutron Star Mergers

    Science.gov (United States)

    Metzger, Brian

    2018-01-01

    The merger of a binary neutron star is accompanied by the ejection of neutron-rich matter into space at velocities up to several tenths that of light, which synthesizes rare heavy isotopes through the rapid neutron capture process (r-process). The radioactive decay of these nuclei was predicted by Metzger et al. (2010) to power an optical transient roughly 1000 times more luminous than a classical nova (a "kilonova"), which is among the most promising electromagnetic counterparts to accompany gravitational wave signal from the merger. I will describe how the luminosities, color, and spectra of the kilonova emission inform the properties of the merging binary (neutron star masses/radii and inclination angle) and the long sought origin of the heaviest elements in the Universe. Results will be discussed in the context of recent discoveries by Advanced LIGO/Virgo.

  20. Binary population synthesis and SNIa rates

    Science.gov (United States)

    Toonen, S.; Nelemans, G.; Bours, M.; Portegies Zwart, S.

    2013-01-01

    Despite the significance of type Ia supernovae (SNeIa) in many fields in astrophysics, SNeIa lack a theoretical explanation. We investigate the potential contribution to the SNeIa rate from the most common progenitor channels using the binary population synthesis (BPS) code SeBa. Using SeBa, we aim constrain binary processes such as the common envelope phase and the efficiency of mass retention of white dwarf accretion. We find that the simulated rates are not sufficient to explain the observed rates. Further, we find that the mass retention efficiency of white dwarf accretion significantly influences the rates, but does not explain all the differences between simulated rates from different BPS codes.

  1. The RIT binary black hole simulations catalog

    Science.gov (United States)

    Healy, James; Lousto, Carlos O.; Zlochower, Yosef; Campanelli, Manuela

    2017-11-01

    The RIT numerical relativity group is releasing a public catalog of black-hole-binary waveforms. The initial release of the catalog consists of 126 recent simulations that include precessing and nonprecessing systems with mass ratios q=m_1/m2 in the range 1/6≤slant q≤slant1 . The catalog contains information about the initial data of the simulation, the waveforms extrapolated to infinity, as well as information about the peak luminosity and final remnant black hole properties. These waveforms can be used to independently interpret gravitational wave signals from laser interferometric detectors and the remnant properties to model the merger of black-hole binaries from initial configurations.

  2. X-Ray Background from Early Binaries

    Science.gov (United States)

    Kohler, Susanna

    2016-11-01

    What impact did X-rays from the first binary star systems have on the universe around them? A new study suggests this radiation may have played an important role during the reionization of our universe.Ionizing the UniverseDuring the period of reionization, the universe reverted from being neutral (as it was during recombination, the previous period)to once again being ionized plasma a state it has remained in since then. This transition, which occurred between 150 million and one billion years after the Big Bang (redshift of 6 z 20), was caused by the formation of the first objects energetic enough to reionize the universes neutral hydrogen.ROSAT image of the soft X-ray background throughout the universe. The different colors represent different energy bands: 0.25 keV (red), 0.75 keV (green), 1.5 keV (blue). [NASA/ROSAT Project]Understanding this time period in particular, determining what sources caused the reionization, and what the properties were of the gas strewn throughout the universe during this time is necessary for us to be able to correctly interpret cosmological observations.Conveniently, the universe has provided us with an interesting clue: the large-scale, diffuse X-ray background we observe all around us. What produced these X-rays, and what impact did this radiation have on the intergalactic medium long ago?The First BinariesA team of scientists led by Hao Xu (UC San Diego) has suggested that the very first generation of stars might be an important contributor to these X-rays.This hypothetical first generation, Population III stars, are thought to have formed before and during reionization from large clouds of gas containing virtually no metals. Studies suggest that a large fraction of Pop III stars formed in binaries and when those stars ended their lives as black holes, ensuing accretion from their companions could produceX-ray radiation.The evolution with redshift of the mean X-ray background intensities. Each curve represents a different

  3. Memory Vulnerability Diagnosis for Binary Program

    Directory of Open Access Journals (Sweden)

    Tang Feng-Yi

    2016-01-01

    Full Text Available Vulnerability diagnosis is important for program security analysis. It is a further step to understand the vulnerability after it is detected, as well as a preparatory step for vulnerability repair or exploitation. This paper mainly analyses the inner theories of major memory vulnerabilities and the threats of them. And then suggests some methods to diagnose several types of memory vulnerabilities for the binary programs, which is a difficult task due to the lack of source code. The diagnosis methods target at buffer overflow, use after free (UAF and format string vulnerabilities. We carried out some tests on the Linux platform to validate the effectiveness of the diagnosis methods. It is proved that the methods can judge the type of the vulnerability given a binary program.

  4. Detectability of Gravitational Waves from High-Redshift Binaries.

    Science.gov (United States)

    Rosado, Pablo A; Lasky, Paul D; Thrane, Eric; Zhu, Xingjiang; Mandel, Ilya; Sesana, Alberto

    2016-03-11

    Recent nondetection of gravitational-wave backgrounds from pulsar timing arrays casts further uncertainty on the evolution of supermassive black hole binaries. We study the capabilities of current gravitational-wave observatories to detect individual binaries and demonstrate that, contrary to conventional wisdom, some are, in principle, detectable throughout the Universe. In particular, a binary with rest-frame mass ≳10^{10}M_{⊙} can be detected by current timing arrays at arbitrarily high redshifts. The same claim will apply for less massive binaries with more sensitive future arrays. As a consequence, future searches for nanohertz gravitational waves could be expanded to target evolving high-redshift binaries. We calculate the maximum distance at which binaries can be observed with pulsar timing arrays and other detectors, properly accounting for redshift and using realistic binary waveforms.

  5. Stellivore extraterrestrials? Binary stars as living systems

    OpenAIRE

    Vidal, Clément

    2016-01-01

    We lack signs of extraterrestrial intelligence (ETI) despite decades of observation in the whole electromagnetic spectrum. Could evidence be buried in existing data? To recognize ETI, we first propose criteria discerning life from non-life based on thermodynamics and living systems theory. Then we extrapolate civilizational development to both external and internal growth. Taken together, these two trends lead to an argument that some existing binary stars might actually be ETI. Since these h...

  6. Nonlinear Tides in Close Binary Systems

    Science.gov (United States)

    Weinberg, Nevin N.; Arras, Phil; Quataert, Eliot; Burkart, Josh

    2012-06-01

    We study the excitation and damping of tides in close binary systems, accounting for the leading-order nonlinear corrections to linear tidal theory. These nonlinear corrections include two distinct physical effects: three-mode nonlinear interactions, i.e., the redistribution of energy among stellar modes of oscillation, and nonlinear excitation of stellar normal modes by the time-varying gravitational potential of the companion. This paper, the first in a series, presents the formalism for studying nonlinear tides and studies the nonlinear stability of the linear tidal flow. Although the formalism we present is applicable to binaries containing stars, planets, and/or compact objects, we focus on non-rotating solar-type stars with stellar or planetary companions. Our primary results include the following: (1) The linear tidal solution almost universally used in studies of binary evolution is unstable over much of the parameter space in which it is employed. More specifically, resonantly excited internal gravity waves in solar-type stars are nonlinearly unstable to parametric resonance for companion masses M' >~ 10-100 M ⊕ at orbital periods P ≈ 1-10 days. The nearly static "equilibrium" tidal distortion is, however, stable to parametric resonance except for solar binaries with P factor of ≈N faster than the standard three-wave parametric instability. These are local instabilities viewed through the lens of global analysis; the coherent global growth rate follows local rates in the regions where the shear is strongest. In solar-type stars, the dynamical tide is unstable to this collective version of the parametric instability for even sub-Jupiter companion masses with P appears particularly efficient at draining energy out of the dynamical tide and may be more important than either wave breaking or parametric resonance at determining the nonlinear dissipation of the dynamical tide.

  7. Binary DNA Nanostructures for Data Encryption

    OpenAIRE

    Halvorsen, Ken; Wong, Wesley P.

    2012-01-01

    We present a simple and secure system for encrypting and decrypting information using DNA self-assembly. Binary data is encoded in the geometry of DNA nanostructures with two distinct conformations. Removing or leaving out a single component reduces these structures to an encrypted solution of ssDNA, whereas adding back this missing "decryption key" causes the spontaneous formation of the message through self-assembly, enabling rapid read out via gel electrophoresis. Applications include auth...

  8. Binary DNA nanostructures for data encryption.

    Science.gov (United States)

    Halvorsen, Ken; Wong, Wesley P

    2012-01-01

    We present a simple and secure system for encrypting and decrypting information using DNA self-assembly. Binary data is encoded in the geometry of DNA nanostructures with two distinct conformations. Removing or leaving out a single component reduces these structures to an encrypted solution of ssDNA, whereas adding back this missing "decryption key" causes the spontaneous formation of the message through self-assembly, enabling rapid read out via gel electrophoresis. Applications include authentication, secure messaging, and barcoding.

  9. Digitizing Villanova University's Eclipsing Binary Card Catalogue

    Science.gov (United States)

    Guzman, Giannina; Dalton, Briana; Conroy, Kyle; Prsa, Andrej

    2018-01-01

    Villanova University’s Department of Astrophysics and Planetary Science has years of hand-written archival data on Eclipsing Binaries at its disposal. This card catalog began at Princeton in the 1930’s with notable contributions from scientists such as Henry Norris Russel. During World War II, the archive was moved to the University of Pennsylvania, which was one of the world centers for Eclipsing Binary research, consequently, the contributions to the catalog during this time were immense. It was then moved to University of Florida at Gainesville before being accepted by Villanova in the 1990’s. The catalog has been kept in storage since then. The objective of this project is to digitize this archive and create a fully functional online catalog that contains the information available on the cards, along with the scan of the actual cards. Our group has built a database using a python-powered infrastructure to contain the collected data. The team also built a prototype web-based searchable interface as a front-end to the catalog. Following the data-entry process, information like the Right Ascension and Declination will be run against SIMBAD and any differences between values will be noted as part of the catalog. Information published online from the card catalog and even discrepancies in information for a star, could be a catalyst for new studies on these Eclipsing Binaries. Once completed, the database-driven interface will be made available to astronomers worldwide. The group will also acquire, from the database, a list of referenced articles that have yet to be found online in order to further pursue their digitization. This list will be comprised of references in the cards that were neither found on ADS nor online during the data-entry process. Pursuing the integration of these references to online queries such as ADS will be an ongoing process that will contribute and further facilitate studies on Eclipsing Binaries.

  10. Asteroseismic modelling of the Binary HD 176465

    Directory of Open Access Journals (Sweden)

    Nsamba B.

    2017-01-01

    Full Text Available The detection and analysis of oscillations in binary star systems is critical in understanding stellar structure and evolution. This is partly because such systems have the same initial chemical composition and age. Solar-like oscillations have been detected by Kepler in both components of the asteroseismic binary HD 176465. We present an independent modelling of each star in this binary system. Stellar models generated using MESA (Modules for Experiments in Stellar Astrophysics were fitted to both the observed individual frequencies and complementary spectroscopic parameters. The individual theoretical oscillation frequencies for the corresponding stellar models were obtained using GYRE as the pulsation code. A Bayesian approach was applied to find the probability distribution functions of the stellar parameters using AIMS (Asteroseismic Inference on a Massive Scale as the optimisation code. The ages of HD 176465 A and HD 176465 B were found to be 2.81 ± 0.48 Gyr and 2.52 ± 0.80 Gyr, respectively. These results are in agreement when compared to previous studies carried out using other asteroseismic modelling techniques and gyrochronology.

  11. Accreting Binary Populations in the Earlier Universe

    Science.gov (United States)

    Hornschemeier, Ann

    2010-01-01

    It is now understood that X-ray binaries dominate the hard X-ray emission from normal star-forming galaxies. Thanks to the deepest (2-4 Ms) Chandra surveys, such galaxies are now being studied in X-rays out to z approximates 4. Interesting X-ray stacking results (based on 30+ galaxies per redshift bin) suggest that the mean rest-frame 2-10 keV luminosity from z=3-4 Lyman break galaxies (LBGs), is comparable to the most powerful starburst galaxies in the local Universe. This result possibly indicates a similar production mechanism for accreting binaries over large cosmological timescales. To understand and constrain better the production of X-ray binaries in high-redshift LBGs, we have utilized XMM-Newton observations of a small sample of z approximates 0.1 GALEX-selected Ultraviolet-Luminous Galaxies (UVLGs); local analogs to high-redshift LBGs. Our observations enable us to study the X-ray emission from LBG-like galaxies on an individual basis, thus allowing us to constrain object-to-object variances in this population. We supplement these results with X-ray stacking constraints using the new 3.2 Ms Chandra Deep Field-South (completed spring 2010) and LBG candidates selected from HST, Swift UVOT, and ground-based data. These measurements provide new X-ray constraints that sample well the entire z=0-4 baseline

  12. Circumstellar disks around binary stars in Taurus

    Energy Technology Data Exchange (ETDEWEB)

    Akeson, R. L. [NASA Exoplanet Science Institute, IPAC/Caltech, Pasadena, CA 91125 (United States); Jensen, E. L. N. [Swarthmore College, Department of Physics and Astronomy, Swarthmore, PA 19081 (United States)

    2014-03-20

    We have conducted a survey of 17 wide (>100 AU) young binary systems in Taurus with the Atacama Large Millimeter Array (ALMA) at two wavelengths. The observations were designed to measure the masses of circumstellar disks in these systems as an aid to understanding the role of multiplicity in star and planet formation. The ALMA observations had sufficient resolution to localize emission within the binary system. Disk emission was detected around all primaries and 10 secondaries, with disk masses as low as 10{sup –4} M {sub ☉}. We compare the properties of our sample to the population of known disks in Taurus and find that the disks from this binary sample match the scaling between stellar mass and millimeter flux of F{sub mm}∝M{sub ∗}{sup 1.5--2.0} to within the scatter found in previous studies. We also compare the properties of the primaries to those of the secondaries and find that the secondary/primary stellar and disk mass ratios are not correlated; in three systems, the circumsecondary disk is more massive than the circumprimary disk, counter to some theoretical predictions.

  13. Project Report: Automatic Sequence Processor Software Analysis

    Science.gov (United States)

    Benjamin, Brandon

    2011-01-01

    The Mission Planning and Sequencing (MPS) element of Multi-Mission Ground System and Services (MGSS) provides space missions with multi-purpose software to plan spacecraft activities, sequence spacecraft commands, and then integrate these products and execute them on spacecraft. Jet Propulsion Laboratory (JPL) is currently is flying many missions. The processes for building, integrating, and testing the multi-mission uplink software need to be improved to meet the needs of the missions and the operations teams that command the spacecraft. The Multi-Mission Sequencing Team is responsible for collecting and processing the observations, experiments and engineering activities that are to be performed on a selected spacecraft. The collection of these activities is called a sequence and ultimately a sequence becomes a sequence of spacecraft commands. The operations teams check the sequence to make sure that no constraints are violated. The workflow process involves sending a program start command, which activates the Automatic Sequence Processor (ASP). The ASP is currently a file-based system that is comprised of scripts written in perl, c-shell and awk. Once this start process is complete, the system checks for errors and aborts if there are any; otherwise the system converts the commands to binary, and then sends the resultant information to be radiated to the spacecraft.

  14. Accuracy of binary black hole waveform models for aligned-spin binaries

    CERN Document Server

    Kumar, Prayush; Fong, Heather; Pfeiffer, Harald P; Boyle, Michael; Hemberger, Daniel A; Kidder, Lawrence E; Scheel, Mark A; Szilagyi, Bela

    2016-01-01

    Coalescing binary black holes are among the primary science targets for second generation ground-based gravitational wave (GW) detectors. Reliable GW models are central to detection of such systems and subsequent parameter estimation. This paper performs a comprehensive analysis of the accuracy of recent waveform models for binary black holes with aligned spins, utilizing a new set of $84$ high-accuracy numerical relativity simulations. Our analysis covers comparable mass binaries ($1\\le m_1/m_2\\le 3$), and samples independently both black hole spins up to dimensionless spin-magnitude of $0.9$ for equal-mass binaries and $0.85$ for unequal mass binaries. Furthermore, we focus on the high-mass regime (total mass $\\gtrsim 50M_\\odot$). The two most recent waveform models considered (PhenomD and SEOBNRv2) both perform very well for signal detection, losing less than 0.5\\% of the recoverable signal-to-noise ratio $\\rho$, except that SEOBNRv2's efficiency drops mildly for both black hole spins aligned with large ma...

  15. A Survey Design for a Sensitive Binary Variable Correlated with Another Nonsensitive Binary Variable

    Directory of Open Access Journals (Sweden)

    Jun-Wu Yu

    2013-01-01

    Full Text Available Tian et al. (2007 introduced a so-called hidden sensitivity model for evaluating the association of two sensitive questions with binary outcomes. However, in practice, we sometimes need to assess the association between one sensitive binary variable (e.g., whether or not a drug user, the number of sex partner being ⩽1 or >1, and so on and one nonsensitive binary variable (e.g., good or poor health status, with or without cervical cancer, and so on. To address this issue, by sufficiently utilizing the information contained in the non-sensitive binary variable, in this paper, we propose a new survey scheme, called combination questionnaire design/model, which consists of a main questionnaire and a supplemental questionnaire. The introduction of the supplemental questionnaire which is indeed a design of direct questioning can effectively reduce the noncompliance behavior since more respondents will not be faced with the sensitive question. Likelihood-based inferences including maximum likelihood estimates via the expectation-maximization algorithm, asymptotic confidence intervals, and bootstrap confidence intervals of parameters of interest are derived. A likelihood ratio test is provided to test the association between the two binary random variables. Bayesian inferences are also discussed. Simulation studies are performed, and a cervical cancer data set in Atlanta is used to illustrate the proposed methods.

  16. A Speckle survey of Southern Hipparcos Visual Doubles and Geneva-Copenhagen Spectroscopic Binaries

    Science.gov (United States)

    Mendez, R. A.; Tokovinin, A.; Horch, E.

    2017-07-01

    The prospect of exquisite-precision parallaxes that will be enabled by the Gaia satellite dramatically changes the landscape of observational stellar astrophysics: If one considers the Hipparcos double stars that lie within 250 pc of the Solar system, a parallax determined by Gaia would yield an uncertainty under 1% for all these objects. In this volume, there are 591 Hipparcos double star discoveries and 160 spectroscopic binaries from the Geneva-Copenhagen spectroscopic survey in the declination range of -20° to -90°. These two samples are important as a source of new binaries from which we will derive masses, component luminosities, and effective temperatures in the coming years. The northern hemisphere counterpart of these objects have been systematically observed at the WIYN Telescope by Horch and collaborators (Horch, E. P., van Altena, W. F., Howell, S. B., Sherry, W. H., & Ciardi, D. R. 2011, AJ, 141, 180). On the other hand, Tokovinin has shown the ability of HRCam at the CTIO/SOAR 4m telescope for binary star research. In 2014 we started a speckle survey with SOAR+HRCam that will complement and significantly extend those previous efforts, allowing us to compile a unique all-sky, volume-limited speckle survey of these two primary samples. So far 12 nights (spread over 3 semesters) have been granted through the Chilean reserved time, with lots of binaries confirmed, many new binaries found, and with several multiple systems discovered (Tokovinin et al., 2015, AJ, 150, 50 and 2016, AJ, 151, 153). Our survey, when complete, will open the door to many sensitive tests of stellar evolution theory, and a large number of new points on the MLR. With this we will truly be able to investigate effects such as metallicity and age on the MLR for the first time. In cases where one component has evolved off the main sequence, age determinations will also be possible.

  17. Tidal Interaction among Red Giants Close Binary Systems in APOGEE Database

    Science.gov (United States)

    Sun, Meng; Arras, Phil; Majewski, Steven R.; Troup, Nicholas William; Weinberg, Nevin N.

    2017-01-01

    Motivated by the newly discovered close binary systems in the Apache Point Observatory Galactic Evolution Experiment (APOGEE-1), the tidal evolution of binaries containing a red giant branch (RGB) star with a stellar or substellar companion was investigated. The tide raised by the companion in the RGB star leads to exchange of angular momentum between the orbit and the stellar spin, causing the orbit to contract. The tidal dissipation rate is computed using turbulent viscosity acting on the equilibrium tidal flow, where careful attention is paid to the effects of reduced viscosity for close-in companions. Evolutionary models for the RGB stars, from the zero-age main sequence to the present, were acquired from the MESA code. "Standard" turbulent viscosity gives rise to such a large orbital decay that many observed systems have decay times much shorter than the RGB evolution time. Several theories for "reduced" turbulent viscosity are investigated, and reduce the number of systems with uncomfortably short decay times.

  18. Measurements of 208 Aitken Visual Binary Stars with a 280 mm Reflector

    Science.gov (United States)

    Serot, J.

    2017-07-01

    This paper presents the measurements of 208 visual binary stars discovered by R.G. Aitken and listed in the WDS catalog. These measurements were obtained between November 2016 and January 2017 with an 11" reflector telescope and an ASI 290MM CMOS-based camera. Binaries with a secondary component up to magnitude 15 and separation between 0.6 and 5 arcsec have been measured. Measurements were carried out on auto-correlograms computed on sequences of a thousand images. This approach allowed us to obtain reliable measurements for pairs with very large difference of magnitude (up to 6). A significant part of the observed pairs had not been observed in the previous decades and show significant movement compared to their last measurement. We also report the discovery of a yet unobserved component for the star A 2455 (WDS 06426+1937).

  19. A Novel DBSCAN Based on Binary Local Sensitive Hashing and Binary-KNN Representation

    Directory of Open Access Journals (Sweden)

    Qing He

    2017-01-01

    Full Text Available We revisit the classic DBSCAN algorithm by proposing a series of strategies to improve its robustness to various densities and its efficiency. Unlike the original DBSCAN, we first use the binary local sensitive hashing (LSH which enables faster region query for the k neighbors of a data point. The binary data representation method based on k neighborhood is then proposed to map the dataset into the Hamming space for faster cluster expansion. We define a core point based on binary influence space to enhance the robustness to various densities. Also, we propose a seed point selection method, which is based on influence space and k neighborhood similarity, to select some seed points instead of all the neighborhood during cluster expansion. Consequently, the number of region queries can be decreased. The experimental results show that the improved algorithm can greatly improve the clustering speed under the premise of ensuring better algorithm clustering accuracy, especially for large-scale datasets.

  20. A NEW CLASS OF NASCENT ECLIPSING BINARIES WITH EXTREME MASS RATIOS

    Energy Technology Data Exchange (ETDEWEB)

    Moe, Maxwell; Stefano, Rosanne Di, E-mail: mmoe@cfa.harvard.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-10, Cambridge, MA 02138 (United States)

    2015-03-10

    Early B-type main-sequence (MS) stars (M {sub 1} ≈ 5-16 M {sub ☉}) with closely orbiting low-mass stellar companions (q = M {sub 2}/M {sub 1} < 0.25) can evolve to produce Type Ia supernovae, low-mass X-ray binaries, and millisecond pulsars. However, the formation mechanism and intrinsic frequency of such close extreme mass-ratio binaries have been debated, especially considering none have hitherto been detected. Utilizing observations of the Large Magellanic Cloud galaxy conducted by the Optical Gravitational Lensing Experiment, we have discovered a new class of eclipsing binaries in which a luminous B-type MS star irradiates a closely orbiting low-mass pre-MS companion that has not yet fully formed. The primordial pre-MS companions have large radii and discernibly reflect much of the light they intercept from the B-type MS primaries (ΔI {sub refl} ≈ 0.02-0.14 mag). For the 18 definitive MS + pre-MS eclipsing binaries in our sample with good model fits to the observed light-curves, we measure short orbital periods P = 3.0-8.5 days, young ages τ ≈ 0.6-8 Myr, and small secondary masses M {sub 2} ≈ 0.8-2.4 M {sub ☉} (q ≈ 0.07-0.36). The majority of these nascent eclipsing binaries are still associated with stellar nurseries, e.g., the system with the deepest eclipse ΔI {sub 1} = 2.8 mag and youngest age τ = 0.6 ± 0.4 Myr is embedded in the bright H II region 30 Doradus. After correcting for selection effects, we find that (2.0 ± 0.6)% of B-type MS stars have companions with short orbital periods P = 3.0-8.5 days and extreme mass ratios q ≈ 0.06-0.25. This is ≈10 times greater than that observed for solar-type MS primaries. We discuss how these new eclipsing binaries provide invaluable insights, diagnostics, and challenges for the formation and evolution of stars, binaries, and H II regions.

  1. Post common envelope binaries from SDSS. VIII. Evidence for disrupted magnetic braking

    Science.gov (United States)

    Schreiber, M. R.; Gänsicke, B. T.; Rebassa-Mansergas, A.; Nebot Gomez-Moran, A.; Southworth, J.; Schwope, A. D.; Müller, M.; Papadaki, C.; Pyrzas, S.; Rabitz, A.; Rodríguez-Gil, P.; Schmidtobreick, L.; Schwarz, R.; Tappert, C.; Toloza, O.; Vogel, J.; Zorotovic, M.

    2010-04-01

    Context. The standard prescription of angular momentum loss in compact binaries assumes magnetic braking to be very efficient as long as the secondary star has a radiative core, but to be negligible if the secondary star is fully convective. This prescription has been developed to explain the orbital period gap observed in the orbital period distribution of cataclysmic variables but has so far not been independently tested. Because the evolutionary time-scale of post common envelope binaries (PCEBs) crucially depends on the rate of angular momentum loss, a fundamental prediction of the disrupted magnetic braking theory is that the relative number of PCEBs should dramatically decrease for companion-star masses exceeding the mass that corresponds to the fully-convective boundary. Aims: We present the results of a large survey of PCEBs among white dwarf/main sequence (WDMS) binaries that allows us to determine the fraction of PCEBs as a function of secondary star mass and therewith to ultimately test the disrupted magnetic braking hypothesis. Methods: We obtained multiple spectroscopic observations spread over at least two nights for 670 WDMS binaries. Systems showing at least 3σ radial velocity variations are considered to be strong PCEB candidates. Taking into account observational selection effects we compare our results with the predictions of binary population simulations. Results: Among the 670 WDMS binaries we find 205 strong PCEB candidates. The fraction of PCEBs among WDMS binaries peaks around Msec ~ 0.25 M⊙ and steeply drops towards higher mass secondary stars in the range of Msec = 0.25-0.4 M⊙. Conclusions: The decrease of the number of PCEBs at the fully convective boundary strongly suggests that the evolutionary time scales of PCEBs containing fully convective secondaries are significantly longer than those of PCEBs with secondaries containing a radiative core. This is consistent with significantly reduced magnetic wind braking of fully convective

  2. Inclination evolution of protoplanetary discs around eccentric binaries

    Science.gov (United States)

    Zanazzi, J. J.; Lai, Dong

    2018-01-01

    It is usually thought that viscous torque works to align a circumbinary disc with the binary's orbital plane. However, recent numerical simulations suggest that the disc may evolve to a configuration perpendicular to the binary orbit ('polar alignment) if the binary is eccentric and the initial disc-binary inclination is sufficiently large. We carry out a theoretical study on the long-term evolution of inclined discs around eccentric binaries, calculating the disc warp profile and dissipative torque acting on the disc. For discs with aspect ratio H/r larger than the viscosity parameter α, bending wave propagation effectively makes the disc precess as a quasi-rigid body, while viscosity acts on the disc warp and twist to drive secular evolution of the disc-binary inclination. We derive a simple analytic criterion (in terms of the binary eccentricity and initial disc orientation) for the disc to evolve towards polar alignment with the eccentric binary. When the disc has a non-negligible angular momentum compared to the binary, the final 'polar alignment' inclination angle is reduced from 90°. For typical protoplanetary disc parameters, the time-scale of the inclination evolution is shorter than the disc lifetime, suggesting that highly inclined discs and planets may exist orbiting eccentric binaries.

  3. Accuracy of binary black hole waveform models for aligned-spin binaries

    Science.gov (United States)

    Kumar, Prayush; Chu, Tony; Fong, Heather; Pfeiffer, Harald P.; Boyle, Michael; Hemberger, Daniel A.; Kidder, Lawrence E.; Scheel, Mark A.; Szilagyi, Bela

    2016-05-01

    Coalescing binary black holes are among the primary science targets for second generation ground-based gravitational wave detectors. Reliable gravitational waveform models are central to detection of such systems and subsequent parameter estimation. This paper performs a comprehensive analysis of the accuracy of recent waveform models for binary black holes with aligned spins, utilizing a new set of 84 high-accuracy numerical relativity simulations. Our analysis covers comparable mass binaries (mass-ratio 1 ≤q ≤3 ), and samples independently both black hole spins up to a dimensionless spin magnitude of 0.9 for equal-mass binaries and 0.85 for unequal mass binaries. Furthermore, we focus on the high-mass regime (total mass ≳50 M⊙ ). The two most recent waveform models considered (PhenomD and SEOBNRv2) both perform very well for signal detection, losing less than 0.5% of the recoverable signal-to-noise ratio ρ , except that SEOBNRv2's efficiency drops slightly for both black hole spins aligned at large magnitude. For parameter estimation, modeling inaccuracies of the SEOBNRv2 model are found to be smaller than systematic uncertainties for moderately strong GW events up to roughly ρ ≲15 . PhenomD's modeling errors are found to be smaller than SEOBNRv2's, and are generally irrelevant for ρ ≲20 . Both models' accuracy deteriorates with increased mass ratio, and when at least one black hole spin is large and aligned. The SEOBNRv2 model shows a pronounced disagreement with the numerical relativity simulation in the merger phase, for unequal masses and simultaneously both black hole spins very large and aligned. Two older waveform models (PhenomC and SEOBNRv1) are found to be distinctly less accurate than the more recent PhenomD and SEOBNRv2 models. Finally, we quantify the bias expected from all four waveform models during parameter estimation for several recovered binary parameters: chirp mass, mass ratio, and effective spin.

  4. COSMIC probes into compact binary formation and evolution

    Science.gov (United States)

    Breivik, Katelyn

    2018-01-01

    The population of compact binaries in the galaxy represents the final state of all binaries that have lived up to the present epoch. Compact binaries present a unique opportunity to probe binary evolution since many of the interactions binaries experience can be imprinted on the compact binary population. By combining binary evolution simulations with catalogs of observable compact binary systems, we can distill the dominant physical processes that govern binary star evolution, as well as predict the abundance and variety of their end products.The next decades herald a previously unseen opportunity to study compact binaries. Multi-messenger observations from telescopes across all wavelengths and gravitational-wave observatories spanning several decades of frequency will give an unprecedented view into the structure of these systems and the composition of their components. Observations will not always be coincident and in some cases may be separated by several years, providing an avenue for simulations to better constrain binary evolution models in preparation for future observations.I will present the results of three population synthesis studies of compact binary populations carried out with the Compact Object Synthesis and Monte Carlo Investigation Code (COSMIC). I will first show how binary-black-hole formation channels can be understood with LISA observations. I will then show how the population of double white dwarfs observed with LISA and Gaia could provide a detailed view of mass transfer and accretion. Finally, I will show that Gaia could discover thousands black holes in the Milky Way through astrometric observations, yielding view into black-hole astrophysics that is complementary to and independent from both X-ray and gravitational-wave astronomy.

  5. Learning moment-based fast local binary descriptor

    Science.gov (United States)

    Bellarbi, Abdelkader; Zenati, Nadia; Otmane, Samir; Belghit, Hayet

    2017-03-01

    Recently, binary descriptors have attracted significant attention due to their speed and low memory consumption; however, using intensity differences to calculate the binary descriptive vector is not efficient enough. We propose an approach to binary description called POLAR_MOBIL, in which we perform binary tests between geometrical and statistical information using moments in the patch instead of the classical intensity binary test. In addition, we introduce a learning technique used to select an optimized set of binary tests with low correlation and high variance. This approach offers high distinctiveness against affine transformations and appearance changes. An extensive evaluation on well-known benchmark datasets reveals the robustness and the effectiveness of the proposed descriptor, as well as its good performance in terms of low computation complexity when compared with state-of-the-art real-time local descriptors.

  6. The extreme Kuiper Belt binary 2001 QW322.

    Science.gov (United States)

    Petit, J-M; Kavelaars, J J; Gladman, B J; Margot, J L; Nicholson, P D; Jones, R L; Parker, J Wm; Ashby, M L N; Bagatin, A Campo; Benavidez, P; Coffey, J; Rousselot, P; Mousis, O; Taylor, P A

    2008-10-17

    The study of binary Kuiper Belt objects helps to probe the dynamic conditions present during planet formation in the solar system. We report on the mutual-orbit determination of 2001 QW322, a Kuiper Belt binary with a very large separation whose properties challenge binary-formation and -evolution theories. Six years of tracking indicate that the binary's mutual-orbit period is approximately 25 to 30 years, that the orbit pole is retrograde and inclined 50 degrees to 62 degrees from the ecliptic plane, and, most surprisingly, that the mutual orbital eccentricity is <0.4. The semimajor axis of 105,000 to 135,000 kilometers is 10 times that of other near-equal-mass binaries. Because this weakly bound binary is prone to orbital disruption by interlopers, its lifetime in its present state is probably less than 1 billion years.

  7. Binary Classification Method of Social Network Users

    Directory of Open Access Journals (Sweden)

    I. A. Poryadin

    2017-01-01

    Full Text Available The subject of research is a binary classification method of social network users based on the data analysis they have placed. Relevance of the task to gain information about a person by examining the content of his/her pages in social networks is exemplified. The most common approach to its solution is a visual browsing. The order of the regional authority in our country illustrates that its using in school education is needed. The article shows restrictions on the visual browsing of pupil’s pages in social networks as a tool for the teacher and the school psychologist and justifies that a process of social network users’ data analysis should be automated. Explores publications, which describe such data acquisition, processing, and analysis methods and considers their advantages and disadvantages. The article also gives arguments to support a proposal to study the classification method of social network users. One such method is credit scoring, which is used in banks and credit institutions to assess the solvency of clients. Based on the high efficiency of the method there is a proposal for significant expansion of its using in other areas of society. The possibility to use logistic regression as the mathematical apparatus of the proposed method of binary classification has been justified. Such an approach enables taking into account the different types of data extracted from social networks. Among them: the personal user data, information about hobbies, friends, graphic and text information, behaviour characteristics. The article describes a number of existing methods of data transformation that can be applied to solve the problem. An experiment of binary gender-based classification of social network users is described. A logistic model obtained for this example includes multiple logical variables obtained by transforming the user surnames. This experiment confirms the feasibility of the proposed method. Further work is to define a system

  8. The Fate of Neutron Star Binary Mergers

    Energy Technology Data Exchange (ETDEWEB)

    Piro, Anthony L. [The Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Giacomazzo, Bruno [Physics Department, University of Trento, via Sommarive 14, I-38123 Trento (Italy); Perna, Rosalba, E-mail: piro@carnegiescience.edu [Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794 (United States)

    2017-08-01

    Following merger, a neutron star (NS) binary can produce roughly one of three different outcomes: (1) a stable NS, (2) a black hole (BH), or (3) a supramassive, rotationally supported NS, which then collapses to a BH following angular momentum losses. Which of these fates occur and in what proportion has important implications for the electromagnetic transient associated with the mergers and the expected gravitational wave (GW) signatures, which in turn depend on the high density equation of state (EOS). Here we combine relativistic calculations of NS masses using realistic EOSs with Monte Carlo population synthesis based on the mass distribution of NS binaries in our Galaxy to predict the distribution of fates expected. For many EOSs, a significant fraction of the remnants are NSs or supramassive NSs. This lends support to scenarios in which a quickly spinning, highly magnetized NS may be powering an electromagnetic transient. This also indicates that it will be important for future GW observatories to focus on high frequencies to study the post-merger GW emission. Even in cases where individual GW events are too low in signal to noise to study the post merger signature in detail, the statistics of how many mergers produce NSs versus BHs can be compared with our work to constrain the EOS. To match short gamma-ray-burst (SGRB) X-ray afterglow statistics, we find that the stiffest EOSs are ruled out. Furthermore, many popular EOSs require a significant fraction of ∼60%–70% of SGRBs to be from NS–BH mergers rather than just binary NSs.

  9. Pycnonuclear reaction rates for binary ionic mixtures

    Science.gov (United States)

    Ichimaru, S.; Ogata, S.; Van Horn, H. M.

    1992-01-01

    Through a combination of compositional scaling arguments and examinations of Monte Carlo simulation results for the interparticle separations in binary-ionic mixture (BIM) solids, we have derived parameterized expressions for the BIM pycnonuclear rates as generalizations of those in one-component solids obtained previously by Salpeter and Van Horn and by Ogata et al. We have thereby discovered a catalyzing effect of the heavier elements, which enhances the rates of reactions among the lighter elements when the charge ratio exceeds a critical value of approximately 2.3.

  10. Binary stars: Mass transfer and chemical composition

    Science.gov (United States)

    Lambert, D. L.

    1982-01-01

    It is noted that mass exchange (and mass loss) within a binary system should produce observable changes in the surface chemical composition of both the mass losing and mass gaining stars as a stellar interior exposed to nucleosyntheses is uncovered. Three topics relating mass exchange and/or mass loss to nucleosynthesis are sketched: the chemical composition of Algol systems; the accretion disk of a cataclysmic variable fed by mass from a dwarf secondary star; and the hypothesis that classical Ba II giants result from mass transfer from a more evolved companion now present as a white dwarf.

  11. Astronomical Plate Archives and Binary Blazars Studies

    Czech Academy of Sciences Publication Activity Database

    Hudec, René

    2011-01-01

    Roč. 32, 1-2 (2011), s. 91-95 ISSN 0250-6335. [Conference on Multiwavelength Variability of Blazars. Guangzhou, 22,09,2010-24,09,2010] R&D Projects: GA ČR GA205/08/1207 Grant - others:GA ČR(CZ) GA102/09/0997; MŠMT(CZ) ME09027 Institutional research plan: CEZ:AV0Z10030501 Keywords : astronomical plates * plate archives archives * binary blazars Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 0.400, year: 2011

  12. The Reflection Effect in Eclipsing Binaries

    Science.gov (United States)

    Gropp, Jeffrey D.; Prsa, Andrej

    2016-01-01

    Using a database of eclipsing binaries (EBs) from the Kepler space telescope, we identified star systems which displayed characteristics corresponding to the reflection effect. The reflection effect is the brightening of one star due to irradiation by its companion. We found 40 candidates amongst the nearly 2,800 EBs in the database. We analyze these candidates and derive parameters and properties of each system using the PHOEBE modeling program. We examine each model fit using probabilistic inference in order to statistically evaluate the best fit model. The model critically tests the reflection effect and provides physical constraints on the principal parameters.

  13. Dynamic Binary Modification Tools, Techniques and Applications

    CERN Document Server

    Hazelwood, Kim

    2011-01-01

    Dynamic binary modification tools form a software layer between a running application and the underlying operating system, providing the powerful opportunity to inspect and potentially modify every user-level guest application instruction that executes. Toolkits built upon this technology have enabled computer architects to build powerful simulators and emulators for design-space exploration, compiler writers to analyze and debug the code generated by their compilers, software developers to fully explore the features, bottlenecks, and performance of their software, and even end-users to extend

  14. A unified kinetic approach to binary nucleation

    Energy Technology Data Exchange (ETDEWEB)

    Kevrekidis, P.G. [Department of Physics, Rutgers University, 136 Frelinghuysen Road]|[E.O.H.S.I., Rutgers University]|[UMDNJ, 170 Frelinghuysen Road, Piscataway, New Jersey 08854-8019 (United States); Lazaridis, M. [Norwegian Institute for Air Research (NILU), Instittutvein 18, P. O. Box 100, N-2007 Kjeller (Norway); Drossinos, Y. [European Commission, Joint Research Centre, I-21020 Ispra (Vatican City State, Holy See) (Italy); Georgopoulos, P.G. [E.O.H.S.I., Rutgers University]|[UMDNJ, 170 Frelinghuysen Road, Piscataway, New Jersey 08854 (United States)

    1999-11-01

    Two different methods to calculate the steady-state nucleation rate in heteromolecular systems proposed by Stauffer (1976) and Langer (1969) are analyzed. Their mathematical equivalence is explicitly demonstrated, thereby obtaining a generic expression for the rate of binary nucleation. Its numerical evaluation does not entail rotation of the coordinate system at the saddle point, but it only requires data in the natural coordinate system of number fluctuations, namely molecular impingement rates, the droplet free energy and its second order derivatives at the saddle point, and the total density of condensible vapors. {copyright} {ital 1999 American Institute of Physics.}

  15. Binary quadratic forms an algorithmic approach

    CERN Document Server

    Buchmann, Johannes

    2007-01-01

    The book deals with algorithmic problems related to binary quadratic forms, such as finding the representations of an integer by a form with integer coefficients, finding the minimum of a form with real coefficients and deciding equivalence of two forms. In order to solve those problems, the book introduces the reader to important areas of number theory such as diophantine equations, reduction theory of quadratic forms, geometry of numbers and algebraic number theory. The book explains applications to cryptography. It requires only basic mathematical knowledge.

  16. The special symplectic structure of binary cubics

    OpenAIRE

    Slupinski, Marcus J.; Stanton, Robert

    2009-01-01

    Let $k$ be a field of characteristic not $2$ or $3$. Let $V$ be the $k$-space of binary cubic polynomials. The natural symplectic structure on $k^2$ promotes to a symplectic structure $\\omega$ on $V$ and from the natural symplectic action of $\\textrm{Sl}(2,k)$ one obtains the symplectic module $(V,\\omega)$. We give a complete analysis of this symplectic module from the point of view of the associated moment map, its norm square $Q$ (essentially the classical discriminant) and the symplectic g...

  17. Electrostatic collection efficiency in binary fluidized beds

    Energy Technology Data Exchange (ETDEWEB)

    Romero, A.; Guardiola, J.; Rincon, J. (Univ. of Alcala de Henares, Madrid (Spain))

    1992-01-01

    Fluidized beds of binary mixtures have been used to clean air streams containing dust particles in the size range 4.4 to 14 {mu}m. All beds were composed of glass beads and plastic granules mixed at different proportions. The effect on the electrostatic collection efficiency of a number of variables, including type of collecting mixture, bed height, and gas velocity, was examined. To calculate the single collection efficiency from experimental results, an early model proposed by Clift et al. was used. The electrostatic collection efficiency was determined by subtracting the other individual mechanism efficiencies from the single particle collection efficiency.

  18. Gas filtration in binary fluidized beds

    Energy Technology Data Exchange (ETDEWEB)

    Rincon, J. (Univ. de Castilla-La Mancha, Ciudad Real (Spain)); Guardiola, J.; Romero, A. (Univ. de Alcala de Henares, Madrid (Spain))

    1992-12-01

    A systematic experimental study of aerosol filtration in a binary fluidized bed of dielectric material is carried out. Measurements of the collection efficiency when such parameters as gas velocity, bed height, collecting mixture, and column diameter are varied over a wide range have been made. Experimental evidence is given to show that charges generated naturally by triboelectrification of the bed dielectric particles can considerably increase the efficiency of such beds. Furthermore, it is demonstrated that a proper choice of the fluidized mixture can significantly improve the performance of such filters.

  19. in Binary Liquid Mixtures of Ethyl benzoate

    Directory of Open Access Journals (Sweden)

    Shaik Babu

    2012-01-01

    Full Text Available Ultrasonic velocity is measured at 2MHz frequency in the binary mixtures of Ethyl Benzoate with 1-Propanol, 1-Butanol, 1-Pentanol and theoretical values of ultrasonic velocity have been evaluated at 303K using Nomoto's relation, Impedance relation, Ideal mixture relation, Junjie's method and free length theory. Theoretical values are compared with the experimental values and the validity of the theories is checked by applying the chi-square test for goodness of fit and by calculating the average percentage error (APE. A good agreement has been found between experimental and Nomoto’s ultrasonic velocity.

  20. On some electrodynamic properties of binary pulsars

    Science.gov (United States)

    Sironi, Lorenzo

    2006-07-01

    The main purpose of my thesis is to examine some electrodynamic properties of binary pulsars, trying to understand the peculiar physical processes that can happen in their magnetospheres; the ultimate aim is to discuss if such systems can be the source of the observed flux of cosmic rays between the knee and the ankle, since the mechanisms of acceleration for the cosmic rays in this range of energies are still unknown. Attention around binary pulsars has arisen after the recent discovery (December 2003) of the first double neutron star system in which both the stars are visible as pulsars (PSR J0737-3039); the inspection of the physical features of this binary pulsar has led to some intriguing possibilities up to now unexplored. In this thesis I will first of all review what is already known about the main properties of this binary system. I will describe in particular the possibility to go further in the verification of the predictions of general relativity with the so-called post-Keplerian parameters; I will discuss the possibility of studying the optical properties of the magnetospheres, since the inclination angle of the orbit is nearly 90° and some orbital phases show an eclipse of the light from one pulsar due to absorption by the magnetosphere of the companion; I will rapidly summarize how the discovery of that binary pulsar can enlarge our knowledge about the origin and evolution of double neutron star systems; lastly, I will examine the increase in the estimate of the Galactic double neutron star merger rate due to the discovery of PSR J0737-3039. I will then summarize the current knowledge about the magnetosphere of a single pulsar. After describing the Gold-Pacini model for the energy loss of the oblique rotator (in which the magnetic and rotational axes are not parallel), I will discuss the Goldreich-Julian model for the aligned axisymmetric rotator in the force-free approximation in which the inertial and gravitational forces are neglected with

  1. The orbital evolution of binary galaxies

    Science.gov (United States)

    Chan, R.; Junqueira, S.

    2001-02-01

    We present the results of self-consistent numerical simulations performed to study the orbital circularization of binary galaxies. We have generalized a previous model (Junqueira & de Freitas Pacheco 1994) and confirmed partially their results. The orbital evolution of pairs of galaxies is faster when we consider interacting pairs with contacting ``live'' galaxy halos but the circularization time remains larger than the Hubble time. Besides, the time behavior of the orbits has changed in comparison with previous work because of tidal forces and dynamical friction acting on the halos.

  2. The Benchmark Eclipsing Binary V530 Ori

    DEFF Research Database (Denmark)

    Torres, Guillermo; Lacy, Claud H. Sandberg; Pavlovski, Kresimir

    2015-01-01

    We report accurate measurements of the physical properties (mass, radius, temperature) of components of the G+M eclipsing binary V530 On. The M-type secondary shows a larger radius and a cooler temperature than predicted by standard stellar evolution models, as has been found for many other low......-mass stars and ascribed to the effects of magnetic activity and/or spots. We show that models from the Dartmouth series that incorporate magnetic fields are able to match the observations with plausible field strengths of 1-2 kG, consistent with a rough estimate we derive for that star....

  3. Binary DNA nanostructures for data encryption.

    Directory of Open Access Journals (Sweden)

    Ken Halvorsen

    Full Text Available We present a simple and secure system for encrypting and decrypting information using DNA self-assembly. Binary data is encoded in the geometry of DNA nanostructures with two distinct conformations. Removing or leaving out a single component reduces these structures to an encrypted solution of ssDNA, whereas adding back this missing "decryption key" causes the spontaneous formation of the message through self-assembly, enabling rapid read out via gel electrophoresis. Applications include authentication, secure messaging, and barcoding.

  4. Computer Vision Using Local Binary Patterns

    CERN Document Server

    Pietikainen, Matti; Zhao, Guoying; Ahonen, Timo

    2011-01-01

    The recent emergence of Local Binary Patterns (LBP) has led to significant progress in applying texture methods to various computer vision problems and applications. The focus of this research has broadened from 2D textures to 3D textures and spatiotemporal (dynamic) textures. Also, where texture was once utilized for applications such as remote sensing, industrial inspection and biomedical image analysis, the introduction of LBP-based approaches have provided outstanding results in problems relating to face and activity analysis, with future scope for face and facial expression recognition, b

  5. Model for magnetic-nonmagnetic binary alloys

    Energy Technology Data Exchange (ETDEWEB)

    Razafimandimby, H. [Departement de Physique, Universite de Toliara, 601 Toliara (Madagascar); Randrianasoloharisoa, D. [LPMR, Universite d' Antananarivo (Madagascar); Rakotomahevitra, A. [Departement des Sciences Exactes, Universite de Mahajanga, BP 155 (Madagascar); Parlebas, J.C. [IPCMS, UMR 7504 CNRS-Universite Louis Pasteur, 23 rue du Loess, BP 43, 67034 Strasbourg (France)

    2007-10-15

    An extension of a mean-field approximation (MFA) developed within standard basis operators (SBO) is used to study magnetism in magnetic-nonmagnetic binary alloys. The Curie temperature is calculated from the free energy within the framework of the present approach. The calculated results are in fair agreement with the theoretical results of other research groups for the same problem but utilizing other methods. Finally, the case of NiPt alloys is briefly examined as an example test for the comparison with experiment. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  6. Improvement of Binary Analysis Components in Automated Malware Analysis Framework

    Science.gov (United States)

    2017-02-21

    AFRL-AFOSR-JP-TR-2017-0018 Improvement of Binary Analysis Components in Automated Malware Analysis Framework Keiji Takeda KEIO UNIVERSITY Final...TYPE Final 3. DATES COVERED (From - To) 26 May 2015 to 25 Nov 2016 4. TITLE AND SUBTITLE Improvement of Binary Analysis Components in Automated Malware ...analyze malicious software ( malware ) with minimum human interaction. The system autonomously analyze malware samples by analyzing malware binary program

  7. Estimation of the Handwritten Text Skew Based on Binary Moments

    OpenAIRE

    D. Brodić, Z. Milivojević

    2012-01-01

    Binary moments represent one of the methods for the text skew estimation in binary images. It has been used widely for the skew identification of the printed text. However, the handwritten text consists of text objects, which are characterized with different skews. Hence, the method should be adapted for the handwritten text. This is achieved with the image splitting into separate text objects made by the bounding boxes. Obtained text objects represent the isolated binary objects. The applica...

  8. Estimation in second order dependency model for multivariate binary data

    Energy Technology Data Exchange (ETDEWEB)

    Ip, E.H.S.

    1995-04-01

    This paper proposes a normal model for multivariate binary data. The normal model is an extension to the bivariate normal model for 2{times}2 contingency table proposed by Pearson. A stochastic algorithm using Gibbs sampler is developed to estimate the parameters for high dimensional binary data. The method is compared to the second order dependency Bahadur-Lazarsfeld representation of binary density. Two examples, one from psychological testing and one from medical science, are used to substantiate the above ideas.

  9. A Survey of Binary Similarity and Distance Measures

    Directory of Open Access Journals (Sweden)

    Seung-Seok Choi

    2010-02-01

    Full Text Available The binary feature vector is one of the most common representations of patterns and measuring similarity and distance measures play a critical role in many problems such as clustering, classification, etc. Ever since Jaccard proposed a similarity measure to classify ecological species in 1901, numerous binary similarity and distance measures have been proposed in various fields. Applying appropriate measures results in more accurate data analysis. Notwithstanding, few comprehensive surveys on binary measures have been conducted. Hence we collected 76 binary similarity and distance measures used over the last century and reveal their correlations through the hierarchical clustering technique.

  10. Modern geothermal power: Binary cycle geothermal power plants

    Science.gov (United States)

    Tomarov, G. V.; Shipkov, A. A.

    2017-04-01

    In the second part of the review of modern geothermal power plant technologies and equipment, a role, a usage scale, and features of application of binary cycle plants in the geothermal economy are considered. Data on the use of low-boiling fluids, their impact on thermal parameters and performance of geothermal binary power units are presented. A retrospective of the use of various low-boiling fluids in industrial binary power units in the world since 1965 is shown. It is noted that the current generating capacity of binary power units running on hydrocarbons is equal to approximately 82.7% of the total installed capacity of all the binary power units in the world. At the same time over the past 5 years, the total installed capacity of geothermal binary power units in 25 countries increased by more than 50%, reaching nearly 1800 MW (hereinafter electric power is indicated), by 2015. A vast majority of the existing binary power plants recovers heat of geothermal fluid in the range of 100-200°C. Binary cycle power plants have an average unit capacity of 6.3 MW, 30.4 MW at single-flash power plants, 37.4 MW at double-flash plants, and 45.4 MW at power plants working on superheated steam. The largest binary cycle geothermal power plants (GeoPP) with an installed capacity of over 60 MW are in operation in the United States and the Philippines. In most cases, binary plants are involved in the production process together with a steam cycle. Requirements to the fluid ensuring safety, reliability, and efficiency of binary power plants using heat of geothermal fluid are determined, and differences and features of their technological processes are shown. Application of binary cycle plants in the technological process of combined GeoPPs makes it possible to recover geothermal fluid more efficiently. Features and advantages of binary cycle plants using multiple fluids, including a Kalina Cycle, are analyzed. Technical characteristics of binary cycle plants produced by various

  11. Inferences about binary stellar populations using gravitational wave observations

    Science.gov (United States)

    Wysocki, Daniel; Gerosa, Davide; O'Shaughnessy, Richard; Belczynski, Krzysztof; Gladysz, Wojciech; Berti, Emanuele; Kesden, Michael; Holz, Daniel

    2018-01-01

    With the dawn of gravitational wave astronomy, enabled by the LIGO and Virgo interferometers, we now have a new window into the Universe. In the short time these detectors have been in use, multiple confirmed detections of gravitational waves from compact binary coalescences have been made. Stellar binary systems are one of the likely progenitors of the observed compact binary sources. If this is indeed the case, then we can use measured properties of these binary systems to learn about their progenitors. We will discuss the Bayesian framework in which we make these inferences, and results which include mass and spin distributions.

  12. Black hole binaries dynamically formed in globular clusters

    Science.gov (United States)

    Park, Dawoo; Kim, Chunglee; Lee, Hyung Mok; Bae, Yeong-Bok; Belczynski, Krzysztof

    2017-08-01

    We investigate properties of black hole (BH) binaries formed in globular clusters via dynamical processes, using directN-body simulations. We pay attention to effects of BH mass function on the total mass and mass ratio distributions of BH binaries ejected from clusters. First, we consider BH populations with two different masses in order to learn basic differences from models with single-mass BHs only. Secondly, we consider continuous BH mass functions adapted from recent studies on massive star evolution in a low metallicity environment, where globular clusters are formed. In this work, we consider only binaries that are formed by three-body processes and ignore stellar evolution and primordial binaries for simplicity. Our results imply that most BH binary mergers take place after they get ejected from the cluster. Also, mass ratios of dynamically formed binaries should be close to 1 or likely to be less than 2:1. Since the binary formation efficiency is larger for higher-mass BHs, it is likely that a BH mass function sampled by gravitational-wave observations would be weighed towards higher masses than the mass function of single BHs for a dynamically formed population. Applying conservative assumptions regarding globular cluster populations such as small BH mass fraction and no primordial binaries, the merger rate of BH binaries originated from globular clusters is estimated to be at least 6.5 yr-1 Gpc-3. Actual rate can be up to more than several times of our conservative estimate.

  13. Absolute properties of the eclipsing binary VV CORVI

    Energy Technology Data Exchange (ETDEWEB)

    Fekel, Francis C.; Henry, Gregory W. [Center of Excellence in Information Systems, Tennessee State University, 3500 John A. Merritt Boulevard, Box 9501, Nashville, TN 37209 (United States); Sowell, James R., E-mail: fekel@evans.tsuniv.edu, E-mail: gregory.w.henry@gmail.com, E-mail: jim.sowell@physics.gatech.edu [School of Physics, Georgia Institute of Technology, Atlanta, GA 30332 (United States)

    2013-12-01

    We have obtained red-wavelength spectroscopy and Johnson B and V differential photoelectric photometry of the eclipsing binary VV Crv = HR 4821. The system is the secondary of the common proper motion double star ADS 8627, which has a separation of 5.''2. VV Crv has an orbital period of 3.144536 days and a low but non-zero eccentricity of 0.085. With the Wilson-Devinney program we have determined a simultaneous solution of our spectroscopic and photometric observations. Those orbital elements produce masses of M {sub 1} = 1.978 ± 0.010 M {sub ☉} and M {sub 2} = 1.513 ± 0.008 M {sub ☉}, and radii of R {sub 1} = 3.375 ± 0.010 R {sub ☉} and R {sub 2} = 1.650 ± 0.008 R {sub ☉} for the primary and secondary, respectively. The effective temperatures of the two components are 6500 K (fixed) and 6638 K, so the star we call the primary is the more massive but cooler and larger component. A comparison with evolutionary tracks indicates that the components are metal rich with [Fe/H] = 0.3, and the system has an age of 1.2 Gyr. The primary is near the end of its main-sequence lifetime and is rotating significantly faster than its pseudosynchronous velocity. The secondary is still well ensconced on the main sequence and is rotating more slowly than its pseudosynchronous rate.

  14. Multilevel Cross-Dependent Binary Longitudinal Data

    KAUST Repository

    Serban, Nicoleta

    2013-10-16

    We provide insights into new methodology for the analysis of multilevel binary data observed longitudinally, when the repeated longitudinal measurements are correlated. The proposed model is logistic functional regression conditioned on three latent processes describing the within- and between-variability, and describing the cross-dependence of the repeated longitudinal measurements. We estimate the model components without employing mixed-effects modeling but assuming an approximation to the logistic link function. The primary objectives of this article are to highlight the challenges in the estimation of the model components, to compare two approximations to the logistic regression function, linear and exponential, and to discuss their advantages and limitations. The linear approximation is computationally efficient whereas the exponential approximation applies for rare events functional data. Our methods are inspired by and applied to a scientific experiment on spectral backscatter from long range infrared light detection and ranging (LIDAR) data. The models are general and relevant to many new binary functional data sets, with or without dependence between repeated functional measurements.

  15. Structure Defect Property Relationships in Binary Intermetallics

    Science.gov (United States)

    Medasani, Bharat; Ding, Hong; Chen, Wei; Persson, Kristin; Canning, Andrew; Haranczyk, Maciej; Asta, Mark

    2015-03-01

    Ordered intermetallics are light weight materials with technologically useful high temperature properties such as creep resistance. Knowledge of constitutional and thermal defects is required to understand these properties. Vacancies and antisites are the dominant defects in the intermetallics and their concentrations and formation enthalpies could be computed by using first principles density functional theory and thermodynamic formalisms such as dilute solution method. Previously many properties of the intermetallics such as melting temperatures and formation enthalpies were statistically analyzed for large number of intermetallics using structure maps and data mining approaches. We undertook a similar exercise to establish the dependence of the defect properties in binary intermetallics on the underlying structural and chemical composition. For more than 200 binary intermetallics comprising of AB, AB2 and AB3 structures, we computed the concentrations and formation enthalpies of vacancies and antisites in a small range of stoichiometries deviating from ideal stoichiometry. The calculated defect properties were datamined to gain predictive capabilities of defect properties as well as to classify the intermetallics for their suitability in high-T applications. Supported by the US DOE under Contract No. DEAC02-05CH11231 under the Materials Project Center grant (Award No. EDCBEE).

  16. Electron Capture Supernovae from Close Binary Systems

    Science.gov (United States)

    Poelarends, Arend J. T.; Wurtz, Scott; Tarka, James; Cole Adams, L.; Hills, Spencer T.

    2017-12-01

    We present the first detailed study of the Electron Capture Supernova Channel (ECSN Channel) for a primary star in a close binary star system. Progenitors of ECSN occupy the lower end of the mass spectrum of supernova progenitors and are thought to form the transition between white dwarf progenitors and core-collapse progenitors. The mass range for ECSN from close binary systems is thought to be wider than the range for single stars, because of the effects of mass transfer on the helium core. Using the MESA stellar evolution code, we explored the parameter space of initial primary masses between 8 and 17 {M}⊙ , using a large grid of models. We find that the initial primary mass and the mass transfer evolution are important factors in the final fate of stars in this mass range. Mass transfer due to Roche lobe overflow during and after carbon burning causes the core to cool down so that it avoids neon ignition, even in helium-free cores with masses up to 1.52 {M}⊙ , which in single stars would ignite neon. If the core is able to contract to high enough densities for electron captures to commence, we find that, for the adopted Ledoux convection criterion, the initial mass range for the primary to evolve into an ECSN is between 13.5 and 17.6 {M}⊙ . The mass ratio, initial period, and mass-loss efficiency only marginally affect the predicted ranges.

  17. Binary Polymer Brushes of Strongly Immiscible Polymers.

    Science.gov (United States)

    Chu, Elza; Babar, Tashnia; Bruist, Michael F; Sidorenko, Alexander

    2015-06-17

    The phenomenon of microphase separation is an example of self-assembly in soft matter and has been observed in block copolymers (BCPs) and similar materials (i.e., supramolecular assemblies (SMAs) and homo/block copolymer blends (HBCs)). In this study, we use microphase separation to construct responsive polymer brushes that collapse to generate periodic surfaces. This is achieved by a chemical reaction between the minor block (10%, poly(4-vinylpyridine)) of the block copolymer and a substrate. The major block of polystyrene (PS) forms mosaic-like arrays of grafted patches that are 10-20 nm in size. Depending on the nature of the assembly (SMA, HBC, or neat BCP) and annealing method (exposure to vapors of different solvents or heating above the glass transition temperature), a range of "mosaic" brushes with different parameters can be obtained. Successive grafting of a secondary polymer (polyacrylamide, PAAm) results in the fabrication of binary polymer brushes (BPBs). Upon being exposed to specific selective solvents, BPBs may adopt different conformations. The surface tension and adhesion of the binary brush are governed by the polymer occupying the top stratum. The "mosaic" brush approach allows for a combination of strongly immiscible polymers in one brush. This facilitates substantial contrast in the surface properties upon switching, previously only possible for substrates composed of predetermined nanostructures. We also demonstrate a possible application of such PS/PAAm brushes in a tunable bioadhesion-bioadhesive (PS on top) or nonbioadhesive (PAAm on top) surface as revealed by Escherichia coli bacterial seeding.

  18. Modeling and analysis of advanced binary cycles

    Energy Technology Data Exchange (ETDEWEB)

    Gawlik, K.

    1997-12-31

    A computer model (Cycle Analysis Simulation Tool, CAST) and a methodology have been developed to perform value analysis for small, low- to moderate-temperature binary geothermal power plants. The value analysis method allows for incremental changes in the levelized electricity cost (LEC) to be determined between a baseline plant and a modified plant. Thermodynamic cycle analyses and component sizing are carried out in the model followed by economic analysis which provides LEC results. The emphasis of the present work is on evaluating the effect of mixed working fluids instead of pure fluids on the LEC of a geothermal binary plant that uses a simple Organic Rankine Cycle. Four resources were studied spanning the range of 265{degrees}F to 375{degrees}F. A variety of isobutane and propane based mixtures, in addition to pure fluids, were used as working fluids. This study shows that the use of propane mixtures at a 265{degrees}F resource can reduce the LEC by 24% when compared to a base case value that utilizes commercial isobutane as its working fluid. The cost savings drop to 6% for a 375{degrees}F resource, where an isobutane mixture is favored. Supercritical cycles were found to have the lowest cost at all resources.

  19. Multilevel cross-dependent binary longitudinal data.

    Science.gov (United States)

    Serban, Nicoleta; Staicu, Ana-Maria; Carroll, Raymond J

    2013-12-01

    We provide insights into new methodology for the analysis of multilevel binary data observed longitudinally, when the repeated longitudinal measurements are correlated. The proposed model is logistic functional regression conditioned on three latent processes describing the within- and between-variability, and describing the cross-dependence of the repeated longitudinal measurements. We estimate the model components without employing mixed-effects modeling but assuming an approximation to the logistic link function. The primary objectives of this article are to highlight the challenges in the estimation of the model components, to compare two approximations to the logistic regression function, linear and exponential, and to discuss their advantages and limitations. The linear approximation is computationally efficient whereas the exponential approximation applies for rare events functional data. Our methods are inspired by and applied to a scientific experiment on spectral backscatter from long range infrared light detection and ranging (LIDAR) data. The models are general and relevant to many new binary functional data sets, with or without dependence between repeated functional measurements. © 2013, The International Biometric Society.

  20. High-quality binary interactome mapping.

    Science.gov (United States)

    Dreze, Matija; Monachello, Dario; Lurin, Claire; Cusick, Michael E; Hill, David E; Vidal, Marc; Braun, Pascal

    2010-01-01

    Physical interactions mediated by proteins are critical for most cellular functions and altogether form a complex macromolecular "interactome" network. Systematic mapping of protein-protein, protein-DNA, protein-RNA, and protein-metabolite interactions at the scale of the whole proteome can advance understanding of interactome networks with applications ranging from single protein functional characterization to discoveries on local and global systems properties. Since the early efforts at mapping protein-protein interactome networks a decade ago, the field has progressed rapidly giving rise to a growing number of interactome maps produced using high-throughput implementations of either binary protein-protein interaction assays or co-complex protein association methods. Although high-throughput methods are often thought to necessarily produce lower quality information than low-throughput experiments, we have recently demonstrated that proteome-scale interactome datasets can be produced with equal or superior quality than that observed in literature-curated datasets derived from large numbers of small-scale experiments. In addition to performing all experimental steps thoroughly and including all necessary controls and quality standards, careful verification of all interacting pairs and validation tests using independent, orthogonal assays are crucial to ensure the release of interactome maps of the highest possible quality. This chapter describes a high-quality, high-throughput binary protein-protein interactome mapping pipeline that includes these features. Copyright © 2010 Elsevier Inc. All rights reserved.

  1. Local Submodularization for Binary Pairwise Energies.

    Science.gov (United States)

    Gorelick, Lena; Boykov, Yuri; Veksler, Olga; Ayed, Ismail Ben; Delong, Andrew

    2017-10-01

    Many computer vision problems require optimization of binary non-submodular energies. We propose a general optimization framework based on local submodular approximations (LSA). Unlike standard LP relaxation methods that linearize the whole energy globally, our approach iteratively approximates the energy locally. On the other hand, unlike standard local optimization methods (e.g., gradient descent or projection techniques) we use non-linear submodular approximations and optimize them without leaving the domain of integer solutions. We discuss two specific LSA algorithms based on trust region and auxiliary function principles, LSA-TR and LSA-AUX. The proposed methods obtain state-of-the-art results on a wide range of applications such as binary deconvolution, curvature regularization, inpainting, segmentation with repulsion and two types of shape priors. Finally, we discuss a move-making extension to the LSA-TR approach. While our paper is focused on pairwise energies, our ideas extend to higher-order problems. The code is available online.

  2. ACOUSTIC EFFECTS ON BINARY AEROELASTICITY MODEL

    Directory of Open Access Journals (Sweden)

    Kok Hwa Yu

    2011-10-01

    Full Text Available Acoustics is the science concerned with the study of sound. The effects of sound on structures attract overwhelm interests and numerous studies were carried out in this particular area. Many of the preliminary investigations show that acoustic pressure produces significant influences on structures such as thin plate, membrane and also high-impedance medium like water (and other similar fluids. Thus, it is useful to investigate the structure response with the presence of acoustics on aircraft, especially on aircraft wings, tails and control surfaces which are vulnerable to flutter phenomena. The present paper describes the modeling of structural-acoustic interactions to simulate the external acoustic effect on binary flutter model. Here, the binary flutter model which illustrated as a rectangular wing is constructed using strip theory with simplified unsteady aerodynamics involving flap and pitch degree of freedom terms. The external acoustic excitation, on the other hand, is modeled using four-node quadrilateral isoparametric element via finite element approach. Both equations then carefully coupled and solved using eigenvalue solution. The mentioned approach is implemented in MATLAB and the outcome of the simulated result are later described, analyzed and illustrated in this paper.

  3. LIGO Finds Lightest Black-Hole Binary

    Science.gov (United States)

    Kohler, Susanna

    2017-11-01

    Wednesdayevening the Laser Interferometer Gravitational-wave Observatory (LIGO) collaboration quietly mentioned that theyd found gravitational waves from yet another black-hole binary back in June. This casual announcement reveals what is so far the lightest pair of black holes weve watched merge opening the door for comparisons to the black holes weve detected by electromagnetic means.A Routine DetectionThe chirp signal of GW170608 detected by LIGO Hanford and LIGO Livingston. [LIGO collaboration 2017]After the fanfare of the previous four black-hole-binary merger announcements over the past year and a half as well as the announcement of the one neutron-star binary merger in August GW170608 marks our entry into the era in which gravitational-wave detections are officially routine.GW170608, a gravitational-wave signal from the merger of two black holes roughly a billion light-years away, was detected in June of this year. This detection occurred after wed already found gravitational waves from several black-hole binaries with the two LIGO detectors in the U.S., but before the Virgo interferometer came online in Europe and increased the joint ability of the detectors to localize sources.Mass estimates for the two components of GW170608 using different models. [LIGO collaboration 2017]Overall, GW170608 is fairly unremarkable: it was detected by both LIGO Hanford and LIGO Livingston some 7 ms apart, and the signal looks not unlike those of the previous LIGO detections. But because were still in the early days of gravitational-wave astronomy, every discovery is still remarkable in some way! GW170608 stands out as being the lightest pair of black holes weve yet to see merge, with component masses before the merger estimated at 12 and 7 times the mass of the Sun.Why Size MattersWith the exception of GW151226, the gravitational-wave signal discovered on Boxing Day last year, all of the black holes that have been discovered by LIGO/Virgo have been quite large: the masses

  4. Backyard Telescopes Watch an Expanding Binary

    Science.gov (United States)

    Kohler, Susanna

    2018-01-01

    What can you do with a team of people armed with backyard telescopes and a decade of patience? Test how binary star systems evolve under Einsteins general theory of relativity!Unusual VariablesCataclysmic variables irregularly brightening binary stars consisting of an accreting white dwarf and a donor star are a favorite target among amateur astronomers: theyre detectable even with small telescopes, and theres a lot we can learn about stellar astrophysics by observing them, if were patient.Diagram of a cataclysmic variable. In an AM CVn, the donor is most likely a white dwarf as well, or a low-mass helium star. [Philip D. Hall]Among the large family of cataclysmic variables is one unusual type: the extremely short-period AM Canum Venaticorum (AM CVn) stars. These rare variables (only 40 are known) are unique in having spectra dominated by helium, suggesting that they contain little or no hydrogen. Because of this, scientists have speculated that the donor stars in these systems are either white dwarfs themselves or very low-mass helium stars.Why study AM CVn stars? Because their unusual configuration allows us to predict the behavior of their orbital evolution. According to the general theory of relativity, the two components of an AM CVn will spiral closer and closer as the system loses angular momentum to gravitational-wave emission. Eventually they will get so close that the low-mass companion star overflows its Roche lobe, beginning mass transfer to the white dwarf. At this point, the orbital evolution will reverse and the binary orbit will expand, increasing its period.CBA member Enrique de Miguel, lead author on the study, with his backyard telescope in Huelva, Spain. [Enrique de Miguel]Backyard Astronomy Hard at WorkMeasuring the evolution of an AM CVns orbital period is the best way to confirm this model, but this is no simple task! To observe this evolution, we first need a system with a period that can be very precisely measured best achieved with an

  5. Assessing fabrication tolerances for a multilevel 2D binary grating for 3D multifocus microscopy.

    Science.gov (United States)

    Davanco, Marcelo; Yu, Liya; Chen, Lei; Luciani, Vincent; Liddle, James Alexander

    2016-05-02

    We perform a comprehensive theoretical assessment of fabrication tolerances for a 2D eight-level binary phase grating that is the central element of a multi-focal plane 3D microscopy apparatus. The fabrication process encompasses a sequence of aligned lithography and etching steps with stringent requirements on layer-to-layer overlay, etch depth and etched sidewall slope, which we show are nonetheless achievable with state-of-the-art optical lithography and etching tools. We also perform broadband spectroscopic diffraction pattern measurements on a fabricated grating, and show how such measurements can be valuable in determining small fabrication errors in diffractive optical elements.

  6. Binary to Octal and Octal to Binary Code Converter Using Mach-Zehnder Interferometer for High Speed Communication

    Science.gov (United States)

    Pal, Amrindra; Kumar, Santosh; Sharma, Sandeep

    2017-05-01

    Binary to octal and octal to binary code converter is a device that allows placing digital information from many inputs to many outputs. Any application of combinational logic circuit can be implemented by using external gates. In this paper, binary to octal and octal to binary code converter is proposed using electro-optic effect inside lithium-niobate based Mach-Zehnder interferometers (MZIs). The MZI structures have powerful capability to switching an optical input signal to a desired output port. The paper constitutes a mathematical description of the proposed device and thereafter simulation using MATLAB. The study is verified using beam propagation method (BPM).

  7. Converting optical scanning holograms of real objects to binary Fourier holograms using an iterative direct binary search algorithm.

    Science.gov (United States)

    Leportier, Thibault; Park, Min Chul; Kim, You Seok; Kim, Taegeun

    2015-02-09

    In this paper, we present a three-dimensional holographic imaging system. The proposed approach records a complex hologram of a real object using optical scanning holography, converts the complex form to binary data, and then reconstructs the recorded hologram using a spatial light modulator (SLM). The conversion from the recorded hologram to a binary hologram is achieved using a direct binary search algorithm. We present experimental results that verify the efficacy of our approach. To the best of our knowledge, this is the first time that a hologram of a real object has been reconstructed using a binary SLM.

  8. Long-term Spectroscopic and Photometric Monitoring of Bright Interacting Algol-type Binary Stars

    Science.gov (United States)

    Reed, Phillip A.

    2018-01-01

    Binary stars have long been used as natural laboratories for studying such fundamental stellar properties as mass. Interacting binaries allow us to examine more complicated aspects such as mass flow between stars, accretion processes, magnetic fields, and stellar mergers. Algol-type interacting binary stars -- consisting of a cool giant or sub-giant donating mass to a much hotter, less evolved, and more massive main-sequence companion -- undergo steady mass transfer and have been used to measure mass transfer rates and to test stellar evolution theories. The method of back-projection Doppler tomography has also been applied to interacting Algols and has produced indirect velocity-space images of the accretion structures (gas streams, accretion disks, etc.) derived from spectroscopic observations of hydrogen and helium emission lines. The accretion structures in several Algol systems have actually been observed to change between disk-like states and stream-like states on timescales as short as several orbital cycles (Richards et al., 2014). Presented here are the first results from a project aimed at studying bright interacting Algol systems with simultaneous mid-resolution (11,000project is to determine the periodicity of changes between stream-like and disk-like states over different temperature regimes, to identify the various accretion phenomena, and to extract their physical properties.

  9. The planetary nebula IC 4776 and its post-common-envelope binary central star

    Science.gov (United States)

    Sowicka, Paulina; Jones, David; Corradi, Romano L. M.; Wesson, Roger; García-Rojas, Jorge; Santander-García, Miguel; Boffin, Henri M. J.; Rodríguez-Gil, Pablo

    2017-11-01

    We present a detailed analysis of IC 4776, a planetary nebula displaying a morphology believed to be typical of central star binarity. The nebula is shown to comprise a compact hourglass-shaped central region and a pair of precessing jet-like structures. Time-resolved spectroscopy of its central star reveals a periodic radial velocity variability consistent with a binary system. Whilst the data are insufficient to accurately determine the parameters of the binary, the most likely solutions indicate that the secondary is probably a low-mass main-sequence star. An empirical analysis of the chemical abundances in IC 4776 indicates that the common-envelope phase may have cut short the asymptotic giant branch evolution of the progenitor. Abundances calculated from recombination lines are found to be discrepant by a factor of approximately 2 relative to those calculated using collisionally excited lines, suggesting a possible correlation between low-abundance discrepancy factors and intermediate-period post-common-envelope central stars and/or Wolf-Rayet central stars. The detection of a radial velocity variability associated with the binarity of the central star of IC 4776 may be indicative of a significant population of (intermediate-period) post-common-envelope binary central stars that would be undetected by classic photometric monitoring techniques.

  10. Absolute parameters of detached binaries in the southern sky - III: HO Tel

    Science.gov (United States)

    Sürgit, D.; Erdem, A.; Engelbrecht, C. A.; van Heerden, H. P.; Manick, R.

    2017-07-01

    We present the first radial velocity analysis of the southern eclipsing binary star HO Tel, based on spectra obtained at the South African Astronomical Observatory in 2013. The orbital solution of this neglected binary gave the quite large spectroscopic mass ratio of 0.921(±0.005). The V light curve from the All Sky Automated Survey (ASAS) and Walraven five-colour (WULBV) photometric light curves (Spoelstra and Van Houten 1972) were solved simultaneously using the Wilson-Devinney code supplemented by the Monte Carlo search method. The final photometric model describes HO Tel as a detached binary star where both component stars fill about three-quarters of their Roche limiting lobes. The masses and radii were found to be 1.88(±0.04) M⊙, 2.28(±0.15) R⊙ and 1.73(±0.04) M⊙, 2.08(±0.16) R⊙ for the primary and secondary components of the system, respectively. The distance to HO Tel was calculated as 282(±30) pc, taking into account interstellar extinction. The evolution case of HO Tel was also examined. Both components of the system are evolved main-sequence stars with an age of approximately 1.1 Gy, when compared to Geneva theoretical evolution models.

  11. MARVELS Radial Velocity Solutions to Seven Kepler Eclipsing Binaries

    Science.gov (United States)

    Heslar, Michael Francis; Thomas, Neil B.; Ge, Jian; Ma, Bo; Herczeg, Alec; Reyes, Alan; SDSS-III MARVELS Team

    2016-01-01

    Eclipsing binaries serve momentous purposes to improve the basis of understanding aspects of stellar astrophysics, such as the accurate calculation of the physical parameters of stars and the enigmatic mass-radius relationship of M and K dwarfs. We report the investigation results of 7 eclipsing binary candidates, initially identified by the Kepler mission, overlapped with the radial velocity observations from the SDSS-III Multi-Object APO Radial-Velocity Exoplanet Large-Area Survey (MARVELS). The RV extractions and spectroscopic solutions of these eclipsing binaries were generated by the University of Florida's 1D data pipeline with a median RV precision of ~60-100 m/s, which was utilized for the DR12 data release. We performed the cross-reference fitting of the MARVELS RV data and the Kepler photometric fluxes obtained from the Kepler Eclipsing Binary Catalog (V2) and modelled the 7 eclipsing binaries in the BinaryMaker3 and PHOEBE programs. This analysis accurately determined the absolute physical and orbital parameters of each binary. Most of the companion stars were determined to have masses of K and M dwarf stars (0.3-0.8 M⊙), and allowed for an investigation into the mass-radius relationship of M and K dwarfs. Among the cases are KIC 9163796, a 122.2 day period "heartbeat star", a recently-discovered class of eccentric binaries known for tidal distortions and pulsations, with a high eccentricity (e~0.75) and KIC 11244501, a 0.29 day period, contact binary with a double-lined spectrum and mass ratio (q~0.45). We also report on the possible reclassification of 2 Kepler eclipsing binary candidates as background eclipsing binaries based on the analysis of the flux measurements, flux ratios of the spectroscopic and photometric solutions, the differences in the FOVs, the image processing of Kepler, and RV and spectral analysis of MARVELS.

  12. DIRECT N-BODY MODELING OF THE OLD OPEN CLUSTER NGC 188: A DETAILED COMPARISON OF THEORETICAL AND OBSERVED BINARY STAR AND BLUE STRAGGLER POPULATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Geller, Aaron M. [Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States); Hurley, Jarrod R. [Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, VIC 3122 (Australia); Mathieu, Robert D., E-mail: a-geller@northwestern.edu, E-mail: mathieu@astro.wisc.edu, E-mail: jhurley@astro.swin.edu.au [Department of Astronomy, University of Wisconsin-Madison, Madison, WI 53706 (United States)

    2013-01-01

    Following on from a recently completed radial-velocity survey of the old (7 Gyr) open cluster NGC 188 in which we studied in detail the solar-type hard binaries and blue stragglers of the cluster, here we investigate the dynamical evolution of NGC 188 through a sophisticated N-body model. Importantly, we employ the observed binary properties of the young (180 Myr) open cluster M35, where possible, to guide our choices for parameters of the initial binary population. We apply pre-main-sequence tidal circularization and a substantial increase to the main-sequence tidal circularization rate, both of which are necessary to match the observed tidal circularization periods in the literature, including that of NGC 188. At 7 Gyr the main-sequence solar-type hard-binary population in the model matches that of NGC 188 in both binary frequency and distributions of orbital parameters. This agreement between the model and observations is in a large part due to the similarities between the NGC 188 and M35 solar-type binaries. Indeed, among the 7 Gyr main-sequence binaries in the model, only those with P {approx}> 1000 days begin to show potentially observable evidence for modifications by dynamical encounters, even after 7 Gyr of evolution within the star cluster. This emphasizes the importance of defining accurate initial conditions for star cluster models, which we propose is best accomplished through comparisons with observations of young open clusters like M35. Furthermore, this finding suggests that observations of the present-day binaries in even old open clusters can provide valuable information on their primordial binary populations. However, despite the model's success at matching the observed solar-type main-sequence population, the model underproduces blue stragglers and produces an overabundance of long-period circular main-sequence-white-dwarf binaries as compared with the true cluster. We explore several potential solutions to the paucity of blue stragglers

  13. PopCORN: Hunting down the differences between binary population synthesis codes

    Science.gov (United States)

    Toonen, S.; Claeys, J. S. W.; Mennekens, N.; Ruiter, A. J.

    2014-02-01

    Context. Binary population synthesis (BPS) modelling is a very effective tool to study the evolution and properties of various types of close binary systems. The uncertainty in the parameters of the model and their effect on a population can be tested in a statistical way, which then leads to a deeper understanding of the underlying (sometimes poorly understood) physical processes involved. Several BPS codes exist that have been developed with different philosophies and aims. Although BPS has been very successful for studies of many populations of binary stars, in the particular case of the study of the progenitors of supernovae Type Ia, the predicted rates and ZAMS progenitors vary substantially between different BPS codes. Aims: To understand the predictive power of BPS codes, we study the similarities and differences in the predictions of four different BPS codes for low- and intermediate-mass binaries. We investigate the differences in the characteristics of the predicted populations, and whether they are caused by different assumptions made in the BPS codes or by numerical effects, e.g. a lack of accuracy in BPS codes. Methods: We compare a large number of evolutionary sequences for binary stars, starting with the same initial conditions following the evolution until the first (and when applicable, the second) white dwarf (WD) is formed. To simplify the complex problem of comparing BPS codes that are based on many (often different) assumptions, we equalise the assumptions as much as possible to examine the inherent differences of the four BPS codes. Results: We find that the simulated populations are similar between the codes. Regarding the population of binaries with one WD, there is very good agreement between the physical characteristics, the evolutionary channels that lead to the birth of these systems, and their birthrates. Regarding the double WD population, there is a good agreement on which evolutionary channels exist to create double WDs and a rough

  14. The Cool Surfaces of Binaries Near-Earth Asteroids

    NARCIS (Netherlands)

    Delbo, Marco; Walsh, K.; Mueller, M.

    2008-01-01

    We present results from thermal-infrared observations of binary near-Earth asteroids (NEAs). These objects, in general, have surface temperatures cooler than the average values for non-binary NEAs. We discuss how this may be evidence of higher-than-average surface thermal inertia. The comparison of

  15. Putting Continuous Metaheuristics to Work in Binary Search Spaces

    Directory of Open Access Journals (Sweden)

    Broderick Crawford

    2017-01-01

    Full Text Available In the real world, there are a number of optimization problems whose search space is restricted to take binary values; however, there are many continuous metaheuristics with good results in continuous search spaces. These algorithms must be adapted to solve binary problems. This paper surveys articles focused on the binarization of metaheuristics designed for continuous optimization.

  16. Inclination of the orbital planes of visual binaries

    Directory of Open Access Journals (Sweden)

    Popović G.M.

    1998-01-01

    Full Text Available The inclination of the orbital planes of 78 visual binaries with known orbits with respect to the galactic was examined. No double star groupings were found having approximately equal orientation of their orbital planes. Viewed the orbital plane north poles there are more binary systems with counterclockwise motion than those moving clockwise.

  17. Binary Biometric Representation through Pairwise Adaptive Phase Quantization

    NARCIS (Netherlands)

    Chen, C.; Veldhuis, Raymond N.J.

    Extracting binary strings from real-valued biometric templates is a fundamental step in template compression and protection systems, such as fuzzy commitment, fuzzy extractor, secure sketch, and helper data systems. Quantization and coding is the straightforward way to extract binary representations

  18. Grammar-Based Specification and Parsing of Binary File Formats

    Directory of Open Access Journals (Sweden)

    William Underwood

    2012-03-01

    Full Text Available The capability to validate and view or play binary file formats, as well as to convert binary file formats to standard or current file formats, is critically important to the preservation of digital data and records. This paper describes the extension of context-free grammars from strings to binary files. Binary files are arrays of data types, such as long and short integers, floating-point numbers and pointers, as well as characters. The concept of an attribute grammar is extended to these context-free array grammars. This attribute grammar has been used to define a number of chunk-based and directory-based binary file formats. A parser generator has been used with some of these grammars to generate syntax checkers (recognizers for validating binary file formats. Among the potential benefits of an attribute grammar-based approach to specification and parsing of binary file formats is that attribute grammars not only support format validation, but support generation of error messages during validation of format, validation of semantic constraints, attribute value extraction (characterization, generation of viewers or players for file formats, and conversion to current or standard file formats. The significance of these results is that with these extensions to core computer science concepts, traditional parser/compiler technologies can potentially be used as a part of a general, cost effective curation strategy for binary file formats.

  19. Observer bias in randomised clinical trials with binary outcomes

    DEFF Research Database (Denmark)

    Hróbjartsson, Asbjørn; Thomsen, Ann Sofia Skou; Emanuelsson, Frida

    2012-01-01

    To evaluate the impact of non-blinded outcome assessment on estimated treatment effects in randomised clinical trials with binary outcomes.......To evaluate the impact of non-blinded outcome assessment on estimated treatment effects in randomised clinical trials with binary outcomes....

  20. Progenitor models of Wolf-Rayet+O binary systems

    NARCIS (Netherlands)

    Petrovic, J.|info:eu-repo/dai/nl/413316556; Langer, N.|info:eu-repo/dai/nl/304829498

    2007-01-01

    Since close WR+O binaries are the result of a strong interaction of both stars in massive close binary systems, they can be used to constrain the highly uncertain mass and angular momentum budget during the major mass- transfer phase. We explore the progenitor evolution of the three best suited WR+O

  1. Binary white dwarfs in the halo of the Milky Way

    NARCIS (Netherlands)

    van Oirschot, Pim; Nelemans, Gijs; Toonen, Silvia; Pols, Onno; Brown, Anthony G. A.; Helmi, Amina; Portegies Zwart, Simon

    Aims: We study single and binary white dwarfs in the inner halo of the Milky Way in order to learn more about the conditions under which the population of halo stars was born, such as the initial mass function (IMF), the star formation history, or the binary fraction. Methods: We simulate the

  2. Dynamical Formation and Merger of Binary Black Holes

    Science.gov (United States)

    Stone, Nicholas

    2017-01-01

    The advent of gravitational wave (GW) astronomy began with Advanced LIGO's 2015 discovery of GWs from coalescing black hole (BH) binaries. GW astronomy holds great promise for testing general relativity, but also for investigating open astrophysical questions not amenable to traditional electromagnetic observations. One such question concerns the origin of stellar mass BH binaries in the universe: do these form primarily from evolution of isolated binaries of massive stars, or do they form through more exotic dynamical channels? The best studied dynamical formation channel involves multibody interactions of BHs and stars in dense globular cluster environments, but many other dynamical scenarios have recently been proposed, ranging from the Kozai effect in hierarchical triple systems to BH binary formation in the outskirts of Toomre-unstable accretion disks surrounding supermassive black holes. The BH binaries formed through these processes will have different distributions of observable parameters (e.g. mass ratios, spins) than BH binaries formed through the evolution of isolated binary stars. In my talk I will overview these and other dynamical formation scenarios, and summarize the key observational tests that will enable Advanced LIGO or other future detectors to determine what formation pathway creates the majority of binary BHs in the universe. NCS thanks NASA, which has funded his work through Einstein postdoctoral grant PF5-160145.

  3. Mass transfer in white dwarf-neutron star binaries

    Science.gov (United States)

    Bobrick, Alexey; Davies, Melvyn B.; Church, Ross P.

    2017-05-01

    We perform hydrodynamic simulations of mass transfer in binaries that contain a white dwarf and a neutron star (WD-NS binaries), and measure the specific angular momentum of material lost from the binary in disc winds. By incorporating our results within a long-term evolution model, we measure the long-term stability of mass transfer in these binaries. We find that only binaries containing helium white dwarfs (WDs) with masses less than a critical mass of MWD, crit = 0.2 M⊙ undergo stable mass transfer and evolve into ultracompact X-ray binaries. Systems with higher mass WDs experience unstable mass transfer, which leads to tidal disruption of the WD. Our low critical mass compared to the standard jet-only model of mass-loss arises from the efficient removal of angular momentum in the mechanical disc winds, which develop at highly super-Eddington mass-transfer rates. We find that the eccentricities expected for WD-NS binaries when they come into contact do not affect the loss of angular momentum, and can only affect the long-term evolution if they change on shorter time-scales than the mass-transfer rate. Our results are broadly consistent with the observed numbers of both ultracompact X-ray binaries and radio pulsars with WD companions. The observed calcium-rich gap transients are consistent with the merger rate of unstable systems with higher mass WDs.

  4. Simultaneous inference of a binary composite endpoint and its components

    DEFF Research Database (Denmark)

    Große Ruse, Mareile; Ritz, Christian; Hothorn, Ludwig A.

    2017-01-01

    Binary composite endpoints offer some advantages as a way to succinctly combine evidence from a number of related binary endpoints recorded in the same clinical trial into a single outcome. However, as some concerns about the clinical relevance as well as the interpretation of such composite endp...

  5. Structured Forms Reference Set of Binary Images (SFRS)

    Science.gov (United States)

    NIST Structured Forms Reference Set of Binary Images (SFRS) (Web, free access)   The NIST Structured Forms Database (Special Database 2) consists of 5,590 pages of binary, black-and-white images of synthesized documents. The documents in this database are 12 different tax forms from the IRS 1040 Package X for the year 1988.

  6. White dwarf-red dwarf binaries in the Galaxy

    NARCIS (Netherlands)

    Besselaar, E.J.M. van den

    2007-01-01

    This PhD thesis shows several studies on white dwarf - red dwarf binaries. White dwarfs are the end products of most stars and red dwarfs are normal hydrogen burning low-mass stars. White dwarf - red dwarf binaries are both blue (white dwarf) and red (red dwarf). Together with the fact that they are

  7. Research note : Miscibility behaviour of binary mixtures of benzyl ...

    African Journals Online (AJOL)

    Miscibility of binary mixtures of benzyl benzoate and liquid paraffin as functions of temperature and composition has been determined using phase separation method. The binary mixtures demonstrated a critical (upper) solution temperature of 35 °C at 101325 Nm-2 with a mixing gap. A tie-line drawn at 28 °C across the ...

  8. Dielectric studies of binary mixtures of -propyl alcohol and ...

    Indian Academy of Sciences (India)

    Dielectric constant (') and dielectric loss (") of -propyl alcohol (PA), ethylenediamine (EDA) and their binary mixtures, for different mole fractions of ethylenediamine have been experimentally measured at 11.15 GHz microwave frequency. Values of density (), viscosity () and square refractive index ( n D 2 ) of binary ...

  9. Microwave dielectric characterization of binary mixture of formamide ...

    Indian Academy of Sciences (India)

    The knowledge of frequency-dependent dielectric properties of binary liquid mix- tures is important both in fundamental studies of solvent structure determination and its dynamics as well as in the practical application of microwave heating process. [1,2]. At a fundamental .... laminoethanol binary system. Pramana – J. Phys.

  10. excess molar volumes, and refractive index of binary mixtures of ...

    African Journals Online (AJOL)

    Preferred Customer

    product of biodiesel and used in many wide industrial applications. Glycerol can be obtained by ... binary mixtures of glycerol + water and glycerol + methanol covering the whole composition range and at 298.15 K .... 114 the mixture. Excess molar volumes on mixing of the binary systems were fitted to Redlich–. Kister [12 ...

  11. A Comparative Study of the Compaction Properties of Binary and ...

    African Journals Online (AJOL)

    Purpose: To comparatively evaluate the tableting properties of binary mixtures and bilayer tablets containing plastic deformation and brittle fracture excipients. Methods: Binary mixture and bilayer tablets of microcrystalline cellulose (MCC), ethyl cellulose, anhydrous lactose and dextrate were prepared by direct compression ...

  12. Spectroscopic Studies of X-Ray Binary Pulsars

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    Abstract. Several new features of X-ray binary pulsars are revealed from recent observations with ASCA, RXTE, BeppoSAX and other X- ray observatories. Among these, I will review in this paper some recent progress in spectroscopic studies of accreting X-ray pulsars in binary sys- tems (XBPs). First, I will discuss soft ...

  13. Formation and Evolution of Binary Systems Containing Collapsed Stars

    Science.gov (United States)

    Rappaport, Saul; West, Donald (Technical Monitor)

    2003-01-01

    This research includes theoretical studies of the formation and evolution of five types of interacting binary systems. Our main focus has been on developing a number of comprehensive population synthesis codes to study the following types of binary systems: (i) cataclysmic variables (#3, #8, #12, #15), (ii) low- and intermediate-mass X-ray binaries (#13, #20, #21), (iii) high-mass X-ray binaries (#14, #17, #22), (iv) recycled binary millisecond pulsars in globular clusters (#5, #10, #ll), and (v) planetary nebulae which form in interacting binaries (#6, #9). The numbers in parentheses refer to papers published or in preparation that are listed in this paper. These codes take a new unified approach to population synthesis studies. The first step involves a Monte Carlo selection of the primordial binaries, including the constituent masses, and orbital separations and eccentricities. Next, a variety of analytic methods are used to evolve the primary star to the point where either a dynamical episode of mass transfer to the secondary occurs (the common envelope phase), or the system evolves down an alternate path. If the residual core of the primary is greater than 2.5 solar mass, it will evolve to Fe core collapse and the production of a neutron star and a supernova explosion. In the case of systems involving neutron stars, a kick velocity is chosen randomly from an appropriate distribution and added to the orbital dynamics which determine the state of the binary system after the supernova explosion. In the third step, all binaries which commence stable mass transfer from the donor star (the original secondary in the binary system) to the compact object, are followed with a detailed binary evolution code. Finally, we include all the relevant dynamics of the binary system. For example, in the case of LMXBs, the binary system, with its recoil velocity from the supernova explosion, is followed in time through its path in the Galactic potential. For our globular cluster

  14. Non-negative Matrix Factorization for Binary Data

    DEFF Research Database (Denmark)

    Larsen, Jacob Søgaard; Clemmensen, Line Katrine Harder

    We propose the Logistic Non-negative Matrix Factorization for decomposition of binary data. Binary data are frequently generated in e.g. text analysis, sensory data, market basket data etc. A common method for analysing non-negative data is the Non-negative Matrix Factorization, though...... this is in theory not appropriate for binary data, and thus we propose a novel Non-negative Matrix Factorization based on the logistic link function. Furthermore we generalize the method to handle missing data. The formulation of the method is compared to a previously proposed method (Tome et al., 2015). We compare...... the performance of the Logistic Non-negative Matrix Factorization to Least Squares Non-negative Matrix Factorization and Kullback-Leibler (KL) Non-negative Matrix Factorization on sets of binary data: a synthetic dataset, a set of student comments on their professors collected in a binary term-document matrix...

  15. What fraction of white dwarfs are members of binary systems?

    Science.gov (United States)

    Holberg, J. B.

    2009-06-01

    White dwarfs were originally discovered as the subordinate faint companions of bright nearby stars (i.e. Sirius B and 40 Eri B). Several general categories of binary systems involving white dwarfs are recognized: Sirius-like systems, where the white dwarf may be difficult to detect, binary systems containing white dwarfs and low mass stars, where the white dwarf is often readily discerned; and double degenerate systems. Different modes of white dwarf discovery influence our perception of both the overall binary fraction and the nature of these systems; proper motion surveys emphasize resolved systems, while photometric surveys emphasize unresolved systems containing relatively hot white dwarfs. Recent studies of the local white dwarf population offer some hope of achieving realistic estimates of the relative number of binary systems containing white dwarfs. A sample of 132 white dwarfs within 20 pc indicates that an individual white dwarf has a probability of 32 ± 8% of occurring within a binary or multiple star system.

  16. Binary classification of items of interest in a repeatable process

    Science.gov (United States)

    Abell, Jeffrey A; Spicer, John Patrick; Wincek, Michael Anthony; Wang, Hui; Chakraborty, Debejyo

    2015-01-06

    A system includes host and learning machines. Each machine has a processor in electrical communication with at least one sensor. Instructions for predicting a binary quality status of an item of interest during a repeatable process are recorded in memory. The binary quality status includes passing and failing binary classes. The learning machine receives signals from the at least one sensor and identifies candidate features. Features are extracted from the candidate features, each more predictive of the binary quality status. The extracted features are mapped to a dimensional space having a number of dimensions proportional to the number of extracted features. The dimensional space includes most of the passing class and excludes at least 90 percent of the failing class. Received signals are compared to the boundaries of the recorded dimensional space to predict, in real time, the binary quality status of a subsequent item of interest.

  17. Dynamic Inertia Weight Binary Bat Algorithm with Neighborhood Search

    Directory of Open Access Journals (Sweden)

    Xingwang Huang

    2017-01-01

    Full Text Available Binary bat algorithm (BBA is a binary version of the bat algorithm (BA. It has been proven that BBA is competitive compared to other binary heuristic algorithms. Since the update processes of velocity in the algorithm are consistent with BA, in some cases, this algorithm also faces the premature convergence problem. This paper proposes an improved binary bat algorithm (IBBA to solve this problem. To evaluate the performance of IBBA, standard benchmark functions and zero-one knapsack problems have been employed. The numeric results obtained by benchmark functions experiment prove that the proposed approach greatly outperforms the original BBA and binary particle swarm optimization (BPSO. Compared with several other heuristic algorithms on zero-one knapsack problems, it also verifies that the proposed algorithm is more able to avoid local minima.

  18. Presence of mixed modes in red giants in binary systems

    Science.gov (United States)

    Themeßl, Nathalie; Hekker, Saskia; Elsworth, Yvonne

    2017-10-01

    The frequencies of oscillation modes in stars contain valueable information about the stellar properties. In red giants the frequency spectrum also contains mixed modes, with both pressure (p) and gravity (g) as restoring force, which are key to understanding the physical conditions in the stellar core. We observe a high fraction of red giants in binary systems, for which g-dominated mixed modes are not pronounced. This trend leads us to investigate whether this is specific for binary systems or a more general feature. We do so by comparing the fraction of stars with only p-dominated mixed modes in binaries and in a larger set of stars from the APOKASC sample. We find only p-dominated mixed modes in about 50% of red giants in detached eclipsing binaries compared to about 4% in the large sample. This could indicate that this phenomenon is tightly related to binarity and that the binary fraction in the APOKASC sample is about 8%.

  19. An Introduction to the Evolution of Single and Binary Stars

    CERN Document Server

    Benacquista, Matthew

    2013-01-01

    An Introduction to the Evolution of Single and Binary Stars provides physicists with an understanding of binary and single star evolution, beginning with a background and introduction of basic astronomical concepts. Although a general treatment of stellar structure and evolution is included, the text stresses the physical processes that lead to stellar mass compact object binaries that may be sources of observable gravitational radiation. Basic concepts of astronomy, stellar structure and atmospheres, single star evolution, binary systems and mass transfer, compact objects, and dynamical systems are covered in the text. Readers will understand the astrophysics behind the populations of compact object binary systems and have sufficient background to delve deeper into specific areas of interest. In addition, derivations of important concepts and worked examples are included. No previous knowledge of astronomy is assumed, although a familiarity with undergraduate quantum mechanics, classical mechanics, and therm...

  20. Solitary waves in dimer binary collision model

    Science.gov (United States)

    Ahsan, Zaid; Jayaprakash, K. R.

    2017-01-01

    Solitary wave propagation in nonlinear diatomic (dimer) chains is a very interesting topic of research in the study of nonlinear lattices. Such waves were recently found to be supported by the essentially nonlinear granular lattice and Toda lattice. An interesting aspect of this discovery is attributed to the realization of a spectrum of the mass ratio (the only system parameter governing the dynamics) that supports the propagation of such waves corresponding to the considered interaction potential. The objective of this exposition is to explore solitary wave propagation in the dimer binary collision (BC) model. Interestingly, the dimer BC model supports solitary wave propagation at a discrete spectrum of mass ratios similar to those observed in granular and Toda dimers. Further, we report a qualitative and one-to-one correspondence between the spectrum of the mass ratio corresponding to the dimer BC model and those corresponding to granular and Toda dimer chains.

  1. Some Bounds on Binary LCD Codes

    OpenAIRE

    Galvez, Lucky; Kim, Jon-Lark; Lee, Nari; Roe, Young Gun; Won, Byung-Sun

    2017-01-01

    A linear code with a complementary dual (or LCD code) is defined to be a linear code $C$ whose dual code $C^{\\perp}$ satisfies $C \\cap C^{\\perp}$= $\\left\\{ \\mathbf{0}\\right\\} $. Let $LCD{[}n,k{]}$ denote the maximum of possible values of $d$ among $[n,k,d]$ binary LCD codes. We give exact values of $LCD{[}n,k{]}$ for $1 \\le k \\le n \\le 12$. We also show that $LCD[n,n-i]=2$ for any $i\\geq2$ and $n\\geq2^{i}$. Furthermore, we show that $LCD[n,k]\\leq LCD[n,k-1]$ for $k$ odd and $LCD[n,k]\\leq LCD[...

  2. Burst Searches for Compact Binary Coalescences

    Science.gov (United States)

    Klimenko, Sergey

    2014-03-01

    Compact Binary coalescences (CBC) are the most promising sources of gravitational waves (GW) for the first detection with advanced GW detectors. Being the most efficient GW emitters among anticipated GW sources, they are also well understood theoretically in the framework of General Relativity. In the talk I'll discuss different flavors of CBC sources and two types of search methods employed in the GW data analysis: template and excess power. While template methods are the most optimal for CBC sources, I will concentrate on the excess power methods, which are typical for searches of generic GW transients (bursts). How to use burst searches for CBC sources? Why would we do this? What can we learn about CBC sources from a burst search? - these and other questions will be discussed in the talk. Supported by NSF grant PHY-1205512.

  3. Local binary patterns new variants and applications

    CERN Document Server

    Jain, Lakhmi; Nanni, Loris; Lumini, Alessandra

    2014-01-01

    This book introduces Local Binary Patterns (LBP), arguably one of the most powerful texture descriptors, and LBP variants. This volume provides the latest reviews of the literature and a presentation of some of the best LBP variants by researchers at the forefront of textual analysis research and research on LBP descriptors and variants. The value of LBP variants is illustrated with reported experiments using many databases representing a diversity of computer vision applications in medicine, biometrics, and other areas. There is also a chapter that provides an excellent theoretical foundation for texture analysis and LBP in particular. A special section focuses on LBP and LBP variants in the area of face recognition, including thermal face recognition. This book will be of value to anyone already in the field as well as to those interested in learning more about this powerful family of texture descriptors.

  4. Learning from nature: binary cooperative complementary nanomaterials.

    Science.gov (United States)

    Su, Bin; Guo, Wei; Jiang, Lei

    2015-03-01

    In this Review, nature-inspired binary cooperative complementary nanomaterials (BCCNMs), consisting of two components with entirely opposite physiochemical properties at the nanoscale, are presented as a novel concept for the building of promising materials. Once the distance between the two nanoscopic components is comparable to the characteristic length of some physical interactions, the cooperation between these complementary building blocks becomes dominant and endows the macroscopic materials with novel and superior properties. The first implementation of the BCCNMs is the design of bio-inspired smart materials with superwettability and their reversible switching between different wetting states in response to various kinds of external stimuli. Coincidentally, recent studies on other types of functional nanomaterials contribute more examples to support the idea of BCCNMs, which suggests a potential yet comprehensive range of future applications in both materials science and engineering. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Periodic Spinodal Decomposition in Solid Binary Mixtures

    Science.gov (United States)

    Onuki, A.

    1982-06-01

    Phase separation is studied when the temperature is made to oscillate around a critical value near a second-order phase transition. In such a case the structure factor is calculated for a one-component system with conserved order parameter using a computational method of Langer, Bar-on and Miller. The structure factor tends to a periodic function when the average of the oscillating temperature is higher than a new critical value which is lower than the equilibrium critical temperature. However, its maximum grows without limit when the average temperature is lowered below the critical value. This is a new type of phase transition where the fluctuations are much enhanced above the thermal level. Besides solid binary mixtures the results of this paper are applicable to uniaxial ferromagnets under strong ultra-sounds in which the spin component along the easy axis is conserved.

  6. Phase equilibrium measurements on nine binary mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Wilding, W.V. [Brigham Young Univ., Provo, UT (United States). Chemical Engineering Dept.; Giles, N.F.; Wilson, L.C. [Wiltec Research Co. Inc., Provo, UT (United States)

    1996-11-01

    Phase equilibrium measurements have been performed on nine binary mixtures. The PTx method was used to obtain vapor-liquid equilibrium data for the following systems at two temperatures each: (aminoethyl)piperazine + diethylenetriamine; 2-butoxyethyl acetate + 2-butoxyethanol; 2-methyl-2-propanol + 2-methylbutane; 2-methyl-2-propanol + 2-methyl-2-butene; methacrylonitrile + methanol; 1-chloro-1,1-difluoroethane + hydrogen chloride; 2-(hexyloxy)ethanol + ethylene glycol; butane + ammonia; propionaldehyde + butane. Equilibrium vapor and liquid phase compositions were derived form the PTx data using the Soave equation of state to represent the vapor phase and the Wilson or the NRTL activity coefficient model to represent the liquid phase. A large immiscibility region exists in the butane + ammonia system at 0 C. Therefore, separate vapor-liquid-liquid equilibrium measurements were performed on this system to more precisely determine the miscibility limits and the composition of the vapor phase in equilibrium with the two liquid phases.

  7. Dual jets from binary black holes.

    Science.gov (United States)

    Palenzuela, Carlos; Lehner, Luis; Liebling, Steven L

    2010-08-20

    The coalescence of supermassive black holes--a natural outcome when galaxies merge--should produce gravitational waves and would likely be associated with energetic electromagnetic events. We have studied the coalescence of such binary black holes within an external magnetic field produced by the expected circumbinary disk surrounding them. Solving the Einstein equations to describe black holes interacting with surrounding plasma, we present numerical evidence for possible jets driven by these systems. Extending the process described by Blandford and Znajek for a single, spinning black hole, the picture that emerges suggests that the electromagnetic field extracts energy from the orbiting black holes, which ultimately merge and settle into the standard Blandford-Znajek scenario. Emissions along these jets could potentially be observable at large distances.

  8. Modeling Flows Around Merging Black Hole Binaries

    Science.gov (United States)

    Centrella, Joan

    2008-01-01

    Coalescing massive black hole binaries are produced by the merger of galaxies. The final stages of the black hole coalescence produce strong gravitational radiation that can be detected by the space-borne LISA. In cases in which the black hole merger takes place in the presence of gas and magnetic fields, various types of electromagnetic signals may also be produced. Modeling such electromagnetic counterparts of the final merger requires evolving the behavior of both gas and fields in the strong-field regions around the black holes. We have taken a first step towards this problem by mapping the flow of pressureless matter in the dynamic, 3-D general relativistic spacetime around the merging black holes. We report on the results of these initial simulations and discuss their likely importance for future hydrodynamical simulations.

  9. Flexible recalibration of binary clinical prediction models.

    Science.gov (United States)

    Dalton, Jarrod E

    2013-01-30

    Calibration in binary prediction models, that is, the agreement between model predictions and observed outcomes, is an important aspect of assessing the models' utility for characterizing risk in future data. A popular technique for assessing model calibration first proposed by D. R. Cox in 1958 involves fitting a logistic model incorporating an intercept and a slope coefficient for the logit of the estimated probability of the outcome; good calibration is evident if these parameters do not appreciably differ from 0 and 1, respectively. However, in practice, the form of miscalibration may sometimes be more complicated. In this article, we expand the Cox calibration model to allow for more general parameterizations and derive a relative measure of miscalibration between two competing models from this more flexible model. We present an example implementation using data from the US Agency for Healthcare Research and Quality. Copyright © 2012 John Wiley & Sons, Ltd.

  10. Shock waves in binary oxides memristors

    Science.gov (United States)

    Tesler, Federico; Tang, Shao; Dobrosavljević, Vladimir; Rozenberg, Marcelo

    2017-09-01

    Progress of silicon based technology is nearing its physical limit, as minimum feature size of components is reaching a mere 5 nm. The resistive switching behavior of transition metal oxides and the associated memristor device is emerging as a competitive technology for next generation electronics. Significant progress has already been made in the past decade and devices are beginning to hit the market; however, it has been mainly the result of empirical trial and error. Hence, gaining theoretical insight is of essence. In the present work we report a new connection between the resistive switching and shock wave formation, a classic topic of non-linear dynamics. We argue that the profile of oxygen ions that migrate during the commutation in insulating binary oxides may form a shock wave, which propagates through a poorly conductive region of the device. We validate the scenario by means of model simulations.

  11. Binary Pulse Compression Techniques for MST Radars

    Science.gov (United States)

    Woodman, R. F.; Sulzer, M. P.; Farley, D. T.

    1984-01-01

    In most mesosphere-stratosphere-troposphere (MST) applications pulsed radars are peak power limited and have excess average power capability. Short pulses are required for good range resolution but the problem of range biguity (signals received simultaneously from more than one altitude) sets a minimum limit on the interpulse period (IPP). Pulse compression is a echnique which allows more of the transmitter average power capacity to be used without scarificing range resolution. Binary phase coding methods for pulse compression are discussed. Many aspects of codes and decoding and their applications to MST experiments are addressed; this includes Barker codes and longer individual codes, and then complementary codes and other code sets. Software decoding, hardware decoders, and coherent integrators are also discussed.

  12. Generating quality tetrahedral meshes from binary volumes

    DEFF Research Database (Denmark)

    Hansen, Mads Fogtmann; Bærentzen, Jakob Andreas; Larsen, Rasmus

    2010-01-01

    generation algorithm on four examples (torus, Stanford dragon, brain mask, and pig back) and report the dihedral angle, aspect ratio and radius-edge ratio. Even though, the algorithm incorporates none of the mentioned quality measures in the compression stage it receives a good score for all these measures......This paper presents two new quality measures for tetrahedra which are smooth and well-suited for gradient based optimization. Both measures are formulated as a distance from the regular tetrahedron and utilize the fact that the covariance of the vertices of a regular tetrahedron is isotropic. We...... use these measures to generate high quality meshes from signed distance maps. This paper also describes an approach for computing (smooth) signed distance maps from binary volumes as volumetric data in many cases originate from segmentation of objects from imaging techniques such as CT, MRI, etc...

  13. Using High-Mass X-ray Binaries to Probe Massive Binary Evolution

    Science.gov (United States)

    Garofali, Kristen; Williams, Ben

    2018-01-01

    High-mass X-ray binaries (HMXBs) provide an exciting window into the underlying processes of both binary as well as massive star evolution. Because HMXBs are systems containing a compact object accreting from a high-mass star at close orbital separations they are also likely progenitors of gamma-ray bursts and gravitational wave sources. I will present work on the classification and age measurements of HMXBs in M33 using a combination of deep Chandra X-ray imaging, and archival Hubble Space Telescope data. I am able to constrain the ages of the HMXB candidates by fitting the color-magnitude diagrams of the surrounding stars, which yield the star formation histories of the surrounding region. Unlike the age distributions measured for HMXB populations in the Magellenic Clouds, the age distribution for the HMXB population in M33 contains a number of extremely young (properties on the observed HMXB population.

  14. Binary Colloidal Alloy Test Conducted on Mir

    Science.gov (United States)

    Hoffmann, Monica I.; Ansari, Rafat R.

    1999-01-01

    Colloids are tiny (submicron) particles suspended in fluid. Paint, ink, and milk are examples of colloids found in everyday life. The Binary Colloidal Alloy Test (BCAT) is part of an extensive series of experiments planned to investigate the fundamental properties of colloids so that scientists can make colloids more useful for technological applications. Some of the colloids studied in BCAT are made of two different sized particles (binary colloidal alloys) that are very tiny, uniform plastic spheres. Under the proper conditions, these colloids can arrange themselves in a pattern to form crystals. These crystals may form the basis of new classes of light switches, displays, and optical devices. Windows made of liquid crystals are already in the marketplace. These windows change their appearance from transparent to opaque when a weak electric current is applied. In the future, if the colloidal crystals can be made to control the passage of light through them, such products could be made much more cheaply. These experiments require the microgravity environment of space because good quality crystals are difficult to produce on Earth because of sedimentation and convection in the fluid. The BCAT experiment hardware included two separate modules for two different experiments. The "Slow Growth" hardware consisted of a 35-mm camera with a 250- exposure photo film cartridge. The camera was aimed toward the sample module, which contained 10 separate colloid samples. A rack of small lights provided backlighting for the photographs. The BCAT hardware was launched on the shuttle and was operated aboard the Russian space station Mir by American astronauts John Blaha and David Wolf (launched September 1996 and returned January 1997; reflown September 1997 and returned January 1998). To begin the experiment, one of these astronauts would mix the samples to disperse the colloidal particles and break up any crystals that might have already formed. Once the samples were mixed and

  15. The algorithm of random length sequences synthesis for frame synchronization of digital television systems

    Directory of Open Access Journals (Sweden)

    Аndriy V. Sadchenko

    2015-12-01

    Full Text Available Digital television systems need to ensure that all digital signals processing operations are performed simultaneously and consistently. Frame synchronization dictated by the need to match phases of transmitter and receiver so that it would be possible to identify the start of a frame. As a frame synchronization signals are often used long length binary sequence with good aperiodic autocorrelation function. Aim: This work is dedicated to the development of the algorithm of random length sequences synthesis. Materials and Methods: The paper provides a comparative analysis of the known sequences, which can be used at present as synchronization ones, revealed their advantages and disadvantages. This work proposes the algorithm for the synthesis of binary synchronization sequences of random length with good autocorrelation properties based on noise generator with a uniform distribution law of probabilities. A "white noise" semiconductor generator is proposed to use as the initial material for the synthesis of binary sequences with desired properties. Results: The statistical analysis of the initial implementations of the "white noise" and synthesized sequences for frame synchronization of digital television is conducted. The comparative analysis of the synthesized sequences with known ones was carried out. The results show the benefits of obtained sequences in compare with known ones. The performed simulations confirm the obtained results. Conclusions: Thus, the search algorithm of binary synchronization sequences with desired autocorrelation properties received. According to this algorithm, the sequence can be longer in length and without length limitations. The received sync sequence can be used for frame synchronization in modern digital communication systems that will increase their efficiency and noise immunity.

  16. Contact binaries in the Trans-neptunian Belt

    Science.gov (United States)

    Thirouin, Audrey; Sheppard, Scott S.

    2017-10-01

    A contact binary is made up of two objects that are almost touching or in contact with each other. These systems have been found in the Near-Earth Object population, the main belt of asteroids, the Jupiter Trojans, the comet population and even in the Trans-neptunian belt.Several studies suggest that up to 30% of the Trans-Neptunian Objects (TNOs) could be contact binaries (Sheppard & Jewitt 2004, Lacerda 2011). Contact binaries are not resolvable with the Hubble Space Telescope because of the small separation between the system's components (Noll et al. 2008). Only lightcurves with a characteristic V-/U-shape at the minimum/maximum of brightness and a large amplitude can identify these contact binaries. Despite an expected high fraction of contact binaries, 2001 QG298 is the only confirmed contact binary in the Trans-Neptunian belt, and 2003 SQ317 is a candidate to this class of systems (Sheppard & Jewitt 2004, Lacerda et al. 2014).Recently, using the Lowell’s 4.3m Discovery Channel Telescope and the 6.5m Magellan Telescope, we started a search for contact binaries at the edge of our Solar System. So far, our survey focused on about 40 objects in different dynamical groups of the Trans-Neptunian belt for sparse or complete lightcurves. We report the discovery of 5 new potential contact binaries converting the current estimate of potential/confirmed contact binaries to 7 objects. With one epoch of observations per object, we are not able to model in detail the systems, but we derive estimate for basic information such as shape, size, density of both objects as well as the separation between the system’s components. In this work, we will present these new systems, their basic characteristics, and we will discuss the potential main reservoir of contact binaries in the Trans-neptunian belt.

  17. Main: Sequences [KOME

    Lifescience Database Archive (English)

    Full Text Available Sequences Amino Acid Sequence Amino Acid sequence of full length cDNA (Longest ORF) kome_ine_full_se...quence_amino_db.fasta.zip kome_ine_full_sequence_amino_db.zip kome_ine_full_sequence_amino_db ...

  18. The sequence of sequencers: The history of sequencing DNA

    Science.gov (United States)

    Heather, James M.; Chain, Benjamin

    2016-01-01

    Determining the order of nucleic acid residues in biological samples is an integral component of a wide variety of research applications. Over the last fifty years large numbers of researchers have applied themselves to the production of techniques and technologies to facilitate this feat, sequencing DNA and RNA molecules. This time-scale has witnessed tremendous changes, moving from sequencing short oligonucleotides to millions of bases, from struggling towards the deduction of the coding sequence of a single gene to rapid and widely available whole genome sequencing. This article traverses those years, iterating through the different generations of sequencing technology, highlighting some of the key discoveries, researchers, and sequences along the way. PMID:26554401

  19. New PN Even Balanced Sequences for Spread-Spectrum Systems

    Directory of Open Access Journals (Sweden)

    Inácio JAL

    2005-01-01

    Full Text Available A new class of pseudonoise even balanced (PN-EB binary spreading sequences is derived from existing classical odd-length families of maximum-length sequences, such as those proposed by Gold, by appending or inserting one extra-zero element (chip to the original sequences. The incentive to generate large families of PN-EB spreading sequences is motivated by analyzing the spreading effect of these sequences from a natural sampling point of view. From this analysis a new definition for PG is established, from which it becomes clear that very high processing gains (PGs can be achieved in band-limited direct-sequence spread-spectrum (DSSS applications by using spreading sequences with zero mean, given that certain conditions regarding spectral aliasing are met. To obtain large families of even balanced (i.e., equal number of ones and zeros sequences, two design criteria are proposed, namely the ranging criterion (RC and the generating ranging criterion (GRC. PN-EB sequences in the polynomial range are derived using these criteria, and it is shown that they exhibit secondary autocorrelation and cross-correlation peaks comparable to the sequences they are derived from. The methods proposed not only facilitate the generation of large numbers of new PN-EB spreading sequences required for CDMA applications, but simultaneously offer high processing gains and good despreading characteristics in multiuser SS scenarios with band-limited noise and interference spectra. Simulation results are presented to confirm the respective claims made.

  20. Pseudorandom noise generators dedicated for acustic measurements

    OpenAIRE

    Español Espinar, Xavier

    2012-01-01

    [ANGLÈS] Study of the noise generators. Implementation software for the KISS Generator in C language and Matlab programm for probability density normalization. Analysis of different noise generator devices dedicated for acoustic measurements. [CASTELLÀ] Estudio de los generadores de ruido. Implementación software del Generador KISS en lenguaje C y progama en Matlab para la normalización de la densidad de probabilidad del generador anterior. Análisis empírico de diferentes dispositivos gene...