Model independent foreground power spectrum estimation using WMAP 5-year data

International Nuclear Information System (INIS)

Ghosh, Tuhin; Souradeep, Tarun; Saha, Rajib; Jain, Pankaj

2009-01-01

In this paper, we propose and implement on WMAP 5 yr data a model independent approach of foreground power spectrum estimation for multifrequency observations of the CMB experiments. Recently, a model independent approach of CMB power spectrum estimation was proposed by Saha et al. 2006. This methodology demonstrates that the CMB power spectrum can be reliably estimated solely from WMAP data without assuming any template models for the foreground components. In the current paper, we extend this work to estimate the galactic foreground power spectrum using the WMAP 5 yr maps following a self-contained analysis. We apply the model independent method in harmonic basis to estimate the foreground power spectrum and frequency dependence of combined foregrounds. We also study the behavior of synchrotron spectral index variation over different regions of the sky. We use the full sky Haslam map as an external template to increase the degrees of freedom, while computing the synchrotron spectral index over the frequency range from 408 MHz to 94 GHz. We compare our results with those obtained from maximum entropy method foreground maps, which are formed in pixel space. We find that relative to our model independent estimates maximum entropy method maps overestimate the foreground power close to galactic plane and underestimates it at high latitudes.

A Linear Mixed-Effects Model of Wireless Spectrum Occupancy

Directory of Open Access Journals (Sweden)

Pagadarai Srikanth

2010-01-01

Full Text Available We provide regression analysis-based statistical models to explain the usage of wireless spectrum across four mid-size US cities in four frequency bands. Specifically, the variations in spectrum occupancy across space, time, and frequency are investigated and compared between different sites within the city as well as with other cities. By applying the mixed-effects models, several conclusions are drawn that give the occupancy percentage and the ON time duration of the licensed signal transmission as a function of several predictor variables.

Sparticle spectrum and constraints in anomaly mediated supersymmetry breaking models

International Nuclear Information System (INIS)

Huitu, K.; Laamanen, J.; Pandita, P.N.

2002-01-01

We study in detail the particle spectrum in anomaly mediated supersymmetry breaking models in which supersymmetry breaking terms are induced by the super-Weyl anomaly. We investigate the minimal anomaly mediated supersymmetry breaking models, gaugino assisted supersymmetry breaking models, as well as models with additional residual nondecoupling D-term contributions due to an extra U(1) gauge symmetry at a high energy scale. We derive sum rules for the sparticle masses in these models which can help in differentiating between them. We also obtain the sparticle spectrum numerically, and compare and contrast the results so obtained for the different types of anomaly mediated supersymmetry breaking models

ChromaStarPy: A Stellar Atmosphere and Spectrum Modeling and Visualization Lab in Python

Science.gov (United States)

Short, C. Ian; Bayer, Jason H. T.; Burns, Lindsey M.

2018-02-01

We announce ChromaStarPy, an integrated general stellar atmospheric modeling and spectrum synthesis code written entirely in python V. 3. ChromaStarPy is a direct port of the ChromaStarServer (CSServ) Java modeling code described in earlier papers in this series, and many of the associated JavaScript (JS) post-processing procedures have been ported and incorporated into CSPy so that students have access to ready-made data products. A python integrated development environment (IDE) allows a student in a more advanced course to experiment with the code and to graphically visualize intermediate and final results, ad hoc, as they are running it. CSPy allows students and researchers to compare modeled to observed spectra in the same IDE in which they are processing observational data, while having complete control over the stellar parameters affecting the synthetic spectra. We also take the opportunity to describe improvements that have been made to the related codes, ChromaStar (CS), CSServ, and ChromaStarDB (CSDB), that, where relevant, have also been incorporated into CSPy. The application may be found at the home page of the OpenStars project: http://www.ap.smu.ca/OpenStars/.

Standard Model mass spectrum in inflationary universe

Energy Technology Data Exchange (ETDEWEB)

Chen, Xingang [Institute for Theory and Computation, Harvard-Smithsonian Center for Astrophysics,60 Garden Street, Cambridge, MA 02138 (United States); Wang, Yi [Department of Physics, The Hong Kong University of Science and Technology,Clear Water Bay, Kowloon, Hong Kong (China); Xianyu, Zhong-Zhi [Center of Mathematical Sciences and Applications, Harvard University,20 Garden Street, Cambridge, MA 02138 (United States)

2017-04-11

We work out the Standard Model (SM) mass spectrum during inflation with quantum corrections, and explore its observable consequences in the squeezed limit of non-Gaussianity. Both non-Higgs and Higgs inflation models are studied in detail. We also illustrate how some inflationary loop diagrams can be computed neatly by Wick-rotating the inflation background to Euclidean signature and by dimensional regularization.

Analytical model spectrum for electrostatic turbulence in tokamaks

International Nuclear Information System (INIS)

Fiedler-Ferrari, N.; Misguich, J.H.

1990-04-01

In this work we present an analytical model spectrum, for three-dimensional electrostatic turbulence (homogeneous, stationary and locally isotropic in the plane perpendicular to the magnetic field), constructed by using experimental results from TFR and TEXT Tokamaks, and satisfying basic symmetry and parity conditions. The proposed spectrum seems to be tractable for explicit analytical calculations of transport processes, and consistent with experimental data. Additional experimental measurements in the bulk plasma remain however necessary in order to determine some unknown spectral properties of parallel propagation

Theoretical modeling of the absorption spectrum of aqueous riboflavin

Science.gov (United States)

Zanetti-Polzi, Laura; Aschi, Massimiliano; Daidone, Isabella; Amadei, Andrea

2017-02-01

In this study we report the modeling of the absorption spectrum of riboflavin in water using a hybrid quantum/classical mechanical approach, the MD-PMM methodology. By means of MD-PMM calculations, with which the effect of riboflavin internal motions and of solvent interactions on the spectroscopic properties can be explicitly taken into account, we obtain an absorption spectrum in very good agreement with the experimental spectrum. In particular, the calculated peak maxima show a consistent improvement with respect to previous computational approaches. Moreover, the calculations show that the interaction with the environment may cause a relevant recombination of the gas-phase electronic states.

A synthetic method of solar spectrum based on LED

Science.gov (United States)

Wang, Ji-qiang; Su, Shi; Zhang, Guo-yu; Zhang, Jian

2017-10-01

A synthetic method of solar spectrum which based on the spectral characteristics of the solar spectrum and LED, and the principle of arbitrary spectral synthesis was studied by using 14 kinds of LED with different central wavelengths.The LED and solar spectrum data were selected by Origin Software firstly, then calculated the total number of LED for each center band by the transformation relation between brightness and illumination and Least Squares Curve Fit in Matlab.Finally, the spectrum curve of AM1.5 standard solar spectrum was obtained. The results met the technical indexes of the solar spectrum matching with ±20% and the solar constant with >0.5.

Probing dark energy using convergence power spectrum and bi-spectrum

Energy Technology Data Exchange (ETDEWEB)

Dinda, Bikash R., E-mail: bikash@ctp-jamia.res.in [Centre for Theoretical Physics, Jamia Millia Islamia, New Delhi-110025 (India)

2017-09-01

Weak lensing convergence statistics is a powerful tool to probe dark energy. Dark energy plays an important role to the structure formation and the effects can be detected through the convergence power spectrum, bi-spectrum etc. One of the most promising and simplest dark energy model is the ΛCDM . However, it is worth investigating different dark energy models with evolving equation of state of the dark energy. In this work, detectability of different dark energy models from ΛCDM model has been explored through convergence power spectrum and bi-spectrum.

On the remarkable spectrum of a non-Hermitian random matrix model

International Nuclear Information System (INIS)

Holz, D E; Orland, H; Zee, A

2003-01-01

A non-Hermitian random matrix model proposed a few years ago has a remarkably intricate spectrum. Various attempts have been made to understand the spectrum, but even its dimension is not known. Using the Dyson-Schmidt equation, we show that the spectrum consists of a non-denumerable set of lines in the complex plane. Each line is the support of the spectrum of a periodic Hamiltonian, obtained by the infinite repetition of any finite sequence of the disorder variables. Our approach is based on the 'theory of words'. We make a complete study of all four-letter words. The spectrum is complicated because our matrix contains everything that will ever be written in the history of the universe, including this particular paper

Solar Flash Sub-Millimeter Wave Range Spectrum Part Radiation Modeling

Directory of Open Access Journals (Sweden)

V. Yu. Shustikov

2015-01-01

Full Text Available Currently, solar flares are under observation on the RT-7.5 radio telescope of BMSTU. This telescope operates in a little-studied range of the spectrum, at wavelengths of 3.2 and 2.2 mm (93 and 140 GHz, thereby providing unique information about parameters of the chromosphere plasma and zone of the temperature minimum. Observations on various instruments provided relatively small amount of data on the radio emission flare at frequencies close to 93 GHz, and at frequency of 140 GHz such observations were not carried out. For these reasons, data collected from the RT-7.5 radio telescope are of high value (Shustikov et al., 2012.This work describes modeling and gives interpretation of the reason for raising flux density spectrum of sub-millimeter radio frequency emission using as an example the GOES flare of class M 5.3 occurred on 04.07.2012 in the active region 11515. This flare was observed on the RT-7.5 radio telescope of BMSTU and was described by Shustikov et al. (2012 and by Smirnova et al. (2013, where it has been suggested that the reason for raising radio frequency emission is a bremsstrahlung of the thermal electrons in the hot plasma of the solar chromosphere. Rough estimates of the plasma temperature at the flare source were obtained.This paper proposes model calculations of the flux density spectrum of the sub-millimeter radio emission based on the gyrosynchrotron Fleischman-Kuznetsov code (Fleishman & Kuznetsov, 2010. Section 1 briefly describes observational data, tools and processing methods used in the work. Section 2 shows results of modeling the flare radio emission. Section 3 discusses results and conclusions.Numerical modeling the sub-millimeter part of the spectrum of the radio flux density for the GOES flare of class M5.3 has been carried out. This flare occurred in the active region 11515 on 04.07.2012. Modeling was based on the observations on the BMSTU’s RT-7.5 radio telescope.The paper draws conclusion based on the

Creating wavelet-based models for real-time synthesis of perceptually convincing environmental sounds

Science.gov (United States)

Miner, Nadine Elizabeth

1998-09-01

This dissertation presents a new wavelet-based method for synthesizing perceptually convincing, dynamic sounds using parameterized sound models. The sound synthesis method is applicable to a variety of applications including Virtual Reality (VR), multi-media, entertainment, and the World Wide Web (WWW). A unique contribution of this research is the modeling of the stochastic, or non-pitched, sound components. This stochastic-based modeling approach leads to perceptually compelling sound synthesis. Two preliminary studies conducted provide data on multi-sensory interaction and audio-visual synchronization timing. These results contributed to the design of the new sound synthesis method. The method uses a four-phase development process, including analysis, parameterization, synthesis and validation, to create the wavelet-based sound models. A patent is pending for this dynamic sound synthesis method, which provides perceptually-realistic, real-time sound generation. This dissertation also presents a battery of perceptual experiments developed to verify the sound synthesis results. These experiments are applicable for validation of any sound synthesis technique.

Video Self-Modeling as an Intervention Strategy for Individuals with Autism Spectrum Disorders

Science.gov (United States)

Gelbar, Nicholas W.; Anderson, Candace; McCarthy, Scott; Buggey, Tom

2012-01-01

Video self-modeling demonstrates promise as an intervention strategy to improve outcomes in individuals with autism spectrum disorders. This article summarizes the empirical evidence supporting the use of video self-modeling with individuals with autism spectrum disorders to increase language and communication, increase social skills, modify…

Model-Based Synthesis of Visual Speech Movements from 3D Video

Directory of Open Access Journals (Sweden)

Edge JamesD

2009-01-01

Full Text Available We describe a method for the synthesis of visual speech movements using a hybrid unit selection/model-based approach. Speech lip movements are captured using a 3D stereo face capture system and split up into phonetic units. A dynamic parameterisation of this data is constructed which maintains the relationship between lip shapes and velocities; within this parameterisation a model of how lips move is built and is used in the animation of visual speech movements from speech audio input. The mapping from audio parameters to lip movements is disambiguated by selecting only the most similar stored phonetic units to the target utterance during synthesis. By combining properties of model-based synthesis (e.g., HMMs, neural nets with unit selection we improve the quality of our speech synthesis.

Modeling and Synthesis Support for the North American Carbon Program

Science.gov (United States)

Baskaran, L.; Cook, R. B.; Thornton, P. E.; Post, W. M.; Wilson, B. E.; Dadi, U.

2007-12-01

The Modeling and Synthesis Thematic Data Center (MAST-DC) supports the North American Carbon Program by providing data products and data management services needed for modeling and synthesis activities. The overall objective of MAST-DC is to provide advanced data management support to NACP investigators doing modeling and synthesis, thereby freeing those investigators from having to perform data management functions. MAST-DC has compiled a number of data products for North America, including sub-pixel land-water content, daily meteorological data, and soil, land cover, and elevation data. In addition, we have developed an internet-based WebGIS system that enables users to browse, query, display, subset, and download spatial data using a standard web browser. For the mid-continent intensive, MAST-DC is working with a group of data assimilation modelers to generate a consistent set of meteorological data to drive bottom-up models.

The mass spectrum of double heavy baryons in new potential quark models

Directory of Open Access Journals (Sweden)

Kovalenko Vladimir

2017-01-01

Full Text Available A new approach to study the mass spectrum of double heavy baryons (QQ′q containing strange and charmed quarks is proposed. It is based on the separation of variables in the Schrodinger equation in the prolate spheroidal coordinates. Two nonrelativistic potential models are considered. In the first model, the interaction potential of the quarks is the sum of the Coulomb and non-spherically symmetrical linear confinement potential. In the second model it is assumed that the quark confinement provided by a spherically symmetric harmonic oscillator potential. In both models the mass spectrum is calculated, and a comparison with previous results from other models is performed.

Synthesis of Bi{sub 25}FeO{sub 39} by molten salts method and its Mössbauer spectrum

Energy Technology Data Exchange (ETDEWEB)

Flores Morales, Shirley Saraí; León Flores, Jesús A.; Pérez Mazariego, José Luis, E-mail: mazariego@ciencias.unam.mx; Marquina Fábrega, Vivianne; Gómez González, Raúl W.

2017-01-01

A sample of Bi{sub 25}FeO{sub 39} was synthesized by the molten salts method in 2 h at 750 °C with KCl-KBr as reaction media. The sample was characterized with X-ray powder diffraction and Mössbauer spectroscopy. The Rietveld refinement of the X-ray diffraction confirms that a sillenite type structure with a cell parameter a=10.190(4) Å was achieved, with only small traces of Bi{sub 2}O{sub 3}. In order to get a Mössbauer spectrum with a good signal to noise ratio, the synthesis was made using 95% enriched α–{sup 57}Fe{sub 2}O{sub 3}. To our knowledge, this is the first time that a Mössbauer spectrum for the Bi{sub 25}FeO{sub 39} has been recorded. The nonappearance of a magnetic sextet confirms its paramagnetic behavior. The measured Mössbauer parameters (IS=0.20±0.004 mm/s and QS=0.2±0.07 mm/s) correspond to Fe{sup +3} in very symmetric surroundings, and rule out some interpretations given to the doublet observed in some Mössbauer spectra of BiFeO{sub 3}.

The evolution of the protein synthesis system. I - A model of a primitive protein synthesis system

Science.gov (United States)

Mizutani, H.; Ponnamperuma, C.

1977-01-01

A model is developed to describe the evolution of the protein synthesis system. The model is comprised of two independent autocatalytic systems, one including one gene (A-gene) and two activated amino acid polymerases (O and A-polymerases), and the other including the addition of another gene (N-gene) and a nucleotide polymerase. Simulation results have suggested that even a small enzymic activity and polymerase specificity could lead the system to the most accurate protein synthesis, as far as permitted by transitions to systems with higher accuracy.

New 1,2,4-triazine bearing compounds: molecular modeling, synthesis and biotesting

Directory of Open Access Journals (Sweden)

Negrutska V. V.

2009-12-01

Full Text Available Aim. To enlarge a spectrum of biologically active compounds in the series of the 1,2,4-triazino[5,6-b] [1,4]benzothiazine (1,2,4-TBT derivatives and reveal among them efficient inhibitors of RNA synthesis Methods. The methods of structure optimization of the 3-oxo-1,2,4-TBT by fragment-oriented substitution, the molecular doking of new structures in a virtual target, the rational chemical synthesis of the theoretically predicted compounds and their testing in the system of transcription in vitro. Results. The series of 1,2,4-TBT derivatives with substituents in the benzene and triazine cycles of a base molecule were synthesized. The testing of synthesized compounds in the in vitro transcription system directed by T7 RNA polymerase revealed the structure- and concentration-dependent inhibition of the RNA synthesis by some of these compounds. The experimental and virtual screening data for all investigated compounds have a good correlation. It was found that most effective derivative is the 3-oxo-8-butyl-1,2,4-TBT which completely inhibited transcription at the concentration of 6 mg/ml. Conclusions. The biotesting results allow us to assume that the inhibition of RNA synthesis is caused by binding of the 3-oxo- 8-butyl-1,2,4-TBT to both free RNA polymerase molecules and those including in a transcriptional complex with DNA

Bayesian modelling of the emission spectrum of the JET Li-BES system

OpenAIRE

Kwak, Sehyun; Svensson, J.; Brix, M.; Ghim, Y. -c.; Contributors, JET

2015-01-01

A Bayesian model of the emission spectrum of the JET lithium beam has been developed to infer the intensity of the Li I (2p-2s) line radiation and associated uncertainties. The detected spectrum for each channel of the lithium beam emission spectroscopy (Li-BES) system is here modelled by a single Li line modified by an instrumental function, Bremsstrahlung background, instrumental offset, and interference filter curve. Both the instrumental function and the interference filter curve are mode...

A Bayesian analysis of inflationary primordial spectrum models using Planck data

Science.gov (United States)

Santos da Costa, Simony; Benetti, Micol; Alcaniz, Jailson

2018-03-01

The current available Cosmic Microwave Background (CMB) data show an anomalously low value of the CMB temperature fluctuations at large angular scales (l power is not explained by the minimal ΛCDM model, and one of the possible mechanisms explored in the literature to address this problem is the presence of features in the primordial power spectrum (PPS) motivated by the early universe physics. In this paper, we analyse a set of cutoff inflationary PPS models using a Bayesian model comparison approach in light of the latest CMB data from the Planck Collaboration. Our results show that the standard power-law parameterisation is preferred over all models considered in the analysis, which motivates the search for alternative explanations for the observed lack of power in the CMB anisotropy spectrum.

Dynamic Model of an Ammonia Synthesis Reactor Based on Open Information

OpenAIRE

Jinasena, Asanthi; Lie, Bernt; Glemmestad, Bjørn

2016-01-01

Ammonia is a widely used chemical, hence the ammonia manufacturing process has become a standard case study in the scientific community. In the field of mathematical modeling of the dynamics of ammonia synthesis reactors, there is a lack of complete and well documented models. Therefore, the main aim of this work is to develop a complete and well documented mathematical model for observing the dynamic behavior of an industrial ammonia synthesis reactor system. The model is complete enough to ...

The Hagedorn Spectrum and the Dual Resonance Model: An Old Love Affair

CERN Document Server

Veneziano, Gabriele

2016-01-01

In this contribution I recall how people working in the late 1960s on the dual resonance model came to the surprising discovery of a Hagedorn-like spectrum, and why they should not have been surprised. I will then turn to discussing the Hagedorn spectrum from a string theory viewpoint (which adds a huge degeneracy to the exponential spectrum). Finally, I will discuss how all this can be reinterpreted in the new incarnation of string theory through the properties of quantum black holes.

Comparison of RF spectrum prediction methods for dynamic spectrum access

Science.gov (United States)

Kovarskiy, Jacob A.; Martone, Anthony F.; Gallagher, Kyle A.; Sherbondy, Kelly D.; Narayanan, Ram M.

2017-05-01

Dynamic spectrum access (DSA) refers to the adaptive utilization of today's busy electromagnetic spectrum. Cognitive radio/radar technologies require DSA to intelligently transmit and receive information in changing environments. Predicting radio frequency (RF) activity reduces sensing time and energy consumption for identifying usable spectrum. Typical spectrum prediction methods involve modeling spectral statistics with Hidden Markov Models (HMM) or various neural network structures. HMMs describe the time-varying state probabilities of Markov processes as a dynamic Bayesian network. Neural Networks model biological brain neuron connections to perform a wide range of complex and often non-linear computations. This work compares HMM, Multilayer Perceptron (MLP), and Recurrent Neural Network (RNN) algorithms and their ability to perform RF channel state prediction. Monte Carlo simulations on both measured and simulated spectrum data evaluate the performance of these algorithms. Generalizing spectrum occupancy as an alternating renewal process allows Poisson random variables to generate simulated data while energy detection determines the occupancy state of measured RF spectrum data for testing. The results suggest that neural networks achieve better prediction accuracy and prove more adaptable to changing spectral statistics than HMMs given sufficient training data.

Excitation spectrum and staggering transformations in lattice quantum models.

Science.gov (United States)

Faria da Veiga, Paulo A; O'Carroll, Michael; Schor, Ricardo

2002-08-01

We consider the energy-momentum excitation spectrum of diverse lattice Hamiltonian operators: the generator of the Markov semigroup of Ginzburg-Landau models with Langevin stochastic dynamics, the Hamiltonian of a scalar quantum field theory, and the Hamiltonian associated with the transfer matrix of a classical ferromagnetic spin system at high temperature. The low-lying spectrum consists of a one-particle state and a two-particle band. The two-particle spectrum is determined using a lattice version of the Bethe-Salpeter equation. In addition to the two-particle band, depending on the lattice dimension and on the attractive or repulsive character of the interaction between the particles of the system, there is, respectively, a bound state below or above the two-particle band. We show how the existence or nonexistence of these bound states can be understood in terms of a nonrelativistic single-particle lattice Schrödinger Hamiltonian with a delta potential. A staggering transformation relates the spectra of the attractive and the repulsive cases.

Synthesis of silver nanoparticles using the Streptomyces coelicolor klmp33 pigment: An antimicrobial agent against extended-spectrum beta-lactamase (ESBL) producing Escherichia coli

International Nuclear Information System (INIS)

Manikprabhu, Deene; Lingappa, K.

2014-01-01

The increasing emergence of extended-spectrum beta-lactamase (ESBL) producing Escherichia coli (E. coli) occurred mainly due to continuous persistent exposure to antibiotics causing high morbidity and mortality so studies in controlling this infection are required. In the present investigation, we developed a synthesis for silver nanoparticles employing a pigment produced by Streptomyces coelicolor klmp33, and assessed the antimicrobial activity of these nanoparticles against ESBL producing E. coli. The ESBL producing E. coli were isolated from urine samples collected from the Gulbarga region in India. As can been seen from our studies, the silver nanoparticles having irregular shapes and size of 28–50 nm showed remarkable antimicrobial activity and moreover the synthesis time is just 20 min and thus the same can be used for formulating pharmaceutical remedies. - Highlights: • Silver nanoparticle synthesis by photo-irradiation method in just 20 min • Isolation of ESBL producing E. coli from urine samples from the Gulbarga region. • Antimicrobial activity of silver nanoparticles against ESBL producing E. coli • The minimum inhibitory concentration of silver nanoparticles against ESBL producing E. coli was 40 μL

Synthesis of silver nanoparticles using the Streptomyces coelicolor klmp33 pigment: An antimicrobial agent against extended-spectrum beta-lactamase (ESBL) producing Escherichia coli

Energy Technology Data Exchange (ETDEWEB)

Manikprabhu, Deene; Lingappa, K., E-mail: lingappak123@gmail.com

2014-12-01

The increasing emergence of extended-spectrum beta-lactamase (ESBL) producing Escherichia coli (E. coli) occurred mainly due to continuous persistent exposure to antibiotics causing high morbidity and mortality so studies in controlling this infection are required. In the present investigation, we developed a synthesis for silver nanoparticles employing a pigment produced by Streptomyces coelicolor klmp33, and assessed the antimicrobial activity of these nanoparticles against ESBL producing E. coli. The ESBL producing E. coli were isolated from urine samples collected from the Gulbarga region in India. As can been seen from our studies, the silver nanoparticles having irregular shapes and size of 28–50 nm showed remarkable antimicrobial activity and moreover the synthesis time is just 20 min and thus the same can be used for formulating pharmaceutical remedies. - Highlights: • Silver nanoparticle synthesis by photo-irradiation method in just 20 min • Isolation of ESBL producing E. coli from urine samples from the Gulbarga region. • Antimicrobial activity of silver nanoparticles against ESBL producing E. coli • The minimum inhibitory concentration of silver nanoparticles against ESBL producing E. coli was 40 μL.

Lorentz Invariant Spectrum of Minimal Chiral Schwinger Model

Science.gov (United States)

Kim, Yong-Wan; Kim, Seung-Kook; Kim, Won-Tae; Park, Young-Jai; Kim, Kee Yong; Kim, Yongduk

We study the Lorentz transformation of the minimal chiral Schwinger model in terms of the alternative action. We automatically obtain a chiral constraint, which is equivalent to the frame constraint introduced by McCabe, in order to solve the frame problem in phase space. As a result we obtain the Lorentz invariant spectrum in any moving frame by choosing a frame parameter.

Shot-by-shot spectrum model for rod-pinch, pulsed radiography machines

Directory of Open Access Journals (Sweden)

Wm M. Wood

2018-02-01

Full Text Available A simplified model of bremsstrahlung production is developed for determining the x-ray spectrum output of a rod-pinch radiography machine, on a shot-by-shot basis, using the measured voltage, V(t, and current, I(t. The motivation for this model is the need for an agile means of providing shot-by-shot spectrum prediction, from a laptop or desktop computer, for quantitative radiographic analysis. Simplifying assumptions are discussed, and the model is applied to the Cygnus rod-pinch machine. Output is compared to wedge transmission data for a series of radiographs from shots with identical target objects. Resulting model enables variation of parameters in real time, thus allowing for rapid optimization of the model across many shots. “Goodness of fit” is compared with output from LSP Particle-In-Cell code, as well as the Monte Carlo Neutron Propagation with Xrays (“MCNPX” model codes, and is shown to provide an excellent predictive representation of the spectral output of the Cygnus machine. Improvements to the model, specifically for application to other geometries, are discussed.

Shot-by-shot spectrum model for rod-pinch, pulsed radiography machines

Science.gov (United States)

Wood, Wm M.

2018-02-01

A simplified model of bremsstrahlung production is developed for determining the x-ray spectrum output of a rod-pinch radiography machine, on a shot-by-shot basis, using the measured voltage, V(t), and current, I(t). The motivation for this model is the need for an agile means of providing shot-by-shot spectrum prediction, from a laptop or desktop computer, for quantitative radiographic analysis. Simplifying assumptions are discussed, and the model is applied to the Cygnus rod-pinch machine. Output is compared to wedge transmission data for a series of radiographs from shots with identical target objects. Resulting model enables variation of parameters in real time, thus allowing for rapid optimization of the model across many shots. "Goodness of fit" is compared with output from LSP Particle-In-Cell code, as well as the Monte Carlo Neutron Propagation with Xrays ("MCNPX") model codes, and is shown to provide an excellent predictive representation of the spectral output of the Cygnus machine. Improvements to the model, specifically for application to other geometries, are discussed.

Particle acceleration model for the broad-band baseline spectrum of the Crab nebula

Science.gov (United States)

Fraschetti, F.; Pohl, M.

2017-11-01

We develop a simple one-zone model of the steady-state Crab nebula spectrum encompassing both the radio/soft X-ray and the GeV/multi-TeV observations. By solving the transport equation for GeV-TeV electrons injected at the wind termination shock as a log-parabola momentum distribution and evolved via energy losses, we determine analytically the resulting differential energy spectrum of photons. We find an impressive agreement with the observed spectrum of synchrotron emission, and the synchrotron self-Compton component reproduces the previously unexplained broad 200-GeV peak that matches the Fermi/Large Area Telescope (LAT) data beyond 1 GeV with the Major Atmospheric Gamma Imaging Cherenkov (MAGIC) data. We determine the parameters of the single log-parabola electron injection distribution, in contrast with multiple broken power-law electron spectra proposed in the literature. The resulting photon differential spectrum provides a natural interpretation of the deviation from power law customarily fitted with empirical multiple broken power laws. Our model can be applied to the radio-to-multi-TeV spectrum of a variety of astrophysical outflows, including pulsar wind nebulae and supernova remnants, as well as to interplanetary shocks.

Synthesis of artificial spectrum-compatible seismic accelerograms

International Nuclear Information System (INIS)

Vrochidou, E; Alvanitopoulos, P F; Andreadis, I; Mallousi, K; Elenas, A

2014-01-01

The Hilbert–Huang transform is used to generate artificial seismic signals compatible with the acceleration spectra of natural seismic records. Artificial spectrum-compatible accelerograms are utilized instead of natural earthquake records for the dynamic response analysis of many critical structures such as hospitals, bridges, and power plants. The realistic estimation of the seismic response of structures involves nonlinear dynamic analysis. Moreover, it requires seismic accelerograms representative of the actual ground acceleration time histories expected at the site of interest. Unfortunately, not many actual records of different seismic intensities are available for many regions. In addition, a large number of seismic accelerograms are required to perform a series of nonlinear dynamic analyses for a reliable statistical investigation of the structural behavior under earthquake excitation. These are the main motivations for generating artificial spectrum-compatible seismic accelerograms and could be useful in earthquake engineering for dynamic analysis and design of buildings. According to the proposed method, a single natural earthquake record is deconstructed into amplitude and frequency components using the Hilbert–Huang transform. The proposed method is illustrated by studying 20 natural seismic records with different characteristics such as different frequency content, amplitude, and duration. Experimental results reveal the efficiency of the proposed method in comparison with well-established and industrial methods in the literature. (paper)

Singular spectrum analysis, Harmonic regression and El-Nino effect ...

Indian Academy of Sciences (India)

42

Keywords: Total ozone; Singular Spectrum Analysis; Spatial interpolation; Multivariate ENSO .... needed for a whole gamut of activities that contribute to the ultimate synthesis ..... −0.0009 3 + 0.0581 2 − 1.0123 + 7.3246, 2 = 0.53…

CF3CH(ONO)CF3: Synthesis, IR spectrum, and use as OH radical source for kinetic and mechanistic studies

DEFF Research Database (Denmark)

Andersen, Mads Peter Sulbæk; Hurley, MD; Ball, JC

2003-01-01

The synthesis, IR spectrum, and first-principles characterization of CF3CH(ONO)CF3 as well as its use as an OH radical source in kinetic and mechanistic studies are reported. CF3CH(ONO)CF3 exists in two conformers corresponding to rotation about the RCO-NO bond. The more prevalent trans conformer......C(O)CF3 and, by implication, OH radicals in 100% yield. CF3CH(ONO)CF3 photolysis is a convenient source of OH radicals in the studies of the yields of CO, CO2, HCHO, and HC(O)OH products which can be difficult to measure using more conventional OH radical sources (e.g., CH3ONO photolysis). CF3CH...

Sound Synthesis of the Harpsichord Using a Computationally Efficient Physical Model

OpenAIRE

Vesa Välimäki; Henri Penttinen; Mikael Laurson; Jonte Knif; Cumhur Erkut

2004-01-01

A sound synthesis algorithm for the harpsichord has been developed by applying the principles of digital waveguide modeling. A modification to the loss filter of the string model is introduced that allows more flexible control of decay rates of partials than is possible with a one-pole digital filter, which is a usual choice for the loss filter. A version of the commuted waveguide synthesis approach is used, where each tone is generated with a parallel combination of the string model and a s...

Constraints on models with a break in the primordial power spectrum

Energy Technology Data Exchange (ETDEWEB)

Li Hong, E-mail: hongli@mail.ihep.ac.c [Institute of High Energy Physics, Chinese Academy of Science, P.O. Box 918-4, Beijing 100049 (China); Theoretical Physics Center for Science Facilities (TPCSF), Chinese Academy of Science (China); Kavli Institute for Theoretical Physics, Chinese Academy of Science, Beijing 100190 (China); Xia Junqing [Scuola Internazionale Superiore di Studi Avanzati, Via Bonomea 265, I-34136 Trieste (Italy); Brandenberger, Robert [Department of Physics, McGill University, 3600 University Street, Montreal, QC, H3A 2T8 (Canada); Institute of High Energy Physics, Chinese Academy of Science, P.O. Box 918-4, Beijing 100049 (China); Theoretical Physics Center for Science Facilities (TPCSF), Chinese Academy of Science (China); Kavli Institute for Theoretical Physics, Chinese Academy of Science, Beijing 100190 (China); Zhang Xinmin [Institute of High Energy Physics, Chinese Academy of Science, P.O. Box 918-4, Beijing 100049 (China); Theoretical Physics Center for Science Facilities (TPCSF), Chinese Academy of Science (China)

2010-07-05

One of the characteristics of the 'Matter Bounce' scenario, an alternative to cosmological inflation for producing a scale-invariant spectrum of primordial adiabatic fluctuations on large scales, is a break in the power spectrum at a characteristic scale, below which the spectral index changes from n{sub s}=1 to n{sub s}=3. We study the constraints which current cosmological data place on the location of such a break, and more generally on the position of the break and the slope at length scales smaller than the break. The observational data we use include the WMAP five-year data set (WMAP5), other CMB data from BOOMERanG, CBI, VSA, and ACBAR, large-scale structure data from the Sloan Digital Sky Survey (SDSS, their luminous red galaxies sample), Type Ia Supernovae data (the 'Union' compilation), and the Sloan Digital Sky Survey Lyman-{alpha} forest power spectrum (Ly{alpha}) data. We employ the Markov Chain Monte Carlo method to constrain the features in the primordial power spectrum which are motivated by the matter bounce model. We give an upper limit on the length scale where the break in the spectrum occurs.

Constraints on models with a break in the primordial power spectrum

International Nuclear Information System (INIS)

Li Hong; Xia Junqing; Brandenberger, Robert; Zhang Xinmin

2010-01-01

One of the characteristics of the 'Matter Bounce' scenario, an alternative to cosmological inflation for producing a scale-invariant spectrum of primordial adiabatic fluctuations on large scales, is a break in the power spectrum at a characteristic scale, below which the spectral index changes from n s =1 to n s =3. We study the constraints which current cosmological data place on the location of such a break, and more generally on the position of the break and the slope at length scales smaller than the break. The observational data we use include the WMAP five-year data set (WMAP5), other CMB data from BOOMERanG, CBI, VSA, and ACBAR, large-scale structure data from the Sloan Digital Sky Survey (SDSS, their luminous red galaxies sample), Type Ia Supernovae data (the 'Union' compilation), and the Sloan Digital Sky Survey Lyman-α forest power spectrum (Lyα) data. We employ the Markov Chain Monte Carlo method to constrain the features in the primordial power spectrum which are motivated by the matter bounce model. We give an upper limit on the length scale where the break in the spectrum occurs.

Comparison of maternal and neonatal outcomes for patients with placenta accreta spectrum between online-to-offline management model with standard care model.

Science.gov (United States)

Sun, Wen; Yu, Lin; Liu, Shiliang; Chen, Yanhong; Chen, Juanjuan; Wen, Shi Wu; Chen, Dunjin

2018-03-01

Online-to-offline is a new model for emergent medical service with the ability to connect care providers with patients on instant basis. This study aims to evaluate maternal and neonatal outcomes in patients with placenta accreta spectrum managed by an online-to-offline care model. Starting from January 1, 2015, management of patients with placenta accreta spectrum was changed from standard care model into an online-to-offline care model through "Wechat" in Guangzhou Medical Centre for Critical Obstetrical Care. This study compared maternal and neonatal outcomes in patients affected by placenta accreta spectrum between 2015 (online-to-offline model) and 2014 (standard care model). A total of 209 cases of placenta accrete spectrum were treated in our center in 2015 and 218 such cases were treated in 2014. Patients treated in 2015 had lower rate of hysterectomy (14.83% versus 20.64%) and shorter hospital stay (7 days versus 8 days). The average interval from admission to emergency cesarean section for critically ill patients was 38.5 min in 2015 versus 50.7 min in 2014. Patients affected by placenta accreta spectrum managed by online-to-offline care model have reduced risk of hysterectomy, shorter hospital stay, and shorter response time from admission to emergency cesarean section. Copyright © 2018 Elsevier B.V. All rights reserved.

A Monte Carlo-based model for simulation of digital chest tomo-synthesis

International Nuclear Information System (INIS)

Ullman, G.; Dance, D. R.; Sandborg, M.; Carlsson, G. A.; Svalkvist, A.; Baath, M.

2010-01-01

The aim of this work was to calculate synthetic digital chest tomo-synthesis projections using a computer simulation model based on the Monte Carlo method. An anthropomorphic chest phantom was scanned in a computed tomography scanner, segmented and included in the computer model to allow for simulation of realistic high-resolution X-ray images. The input parameters to the model were adapted to correspond to the VolumeRAD chest tomo-synthesis system from GE Healthcare. Sixty tomo-synthesis projections were calculated with projection angles ranging from + 15 to -15 deg. The images from primary photons were calculated using an analytical model of the anti-scatter grid and a pre-calculated detector response function. The contributions from scattered photons were calculated using an in-house Monte Carlo-based model employing a number of variance reduction techniques such as the collision density estimator. Tomographic section images were reconstructed by transferring the simulated projections into the VolumeRAD system. The reconstruction was performed for three types of images using: (i) noise-free primary projections, (ii) primary projections including contributions from scattered photons and (iii) projections as in (ii) with added correlated noise. The simulated section images were compared with corresponding section images from projections taken with the real, anthropomorphic phantom from which the digital voxel phantom was originally created. The present article describes a work in progress aiming towards developing a model intended for optimisation of chest tomo-synthesis, allowing for simulation of both existing and future chest tomo-synthesis systems. (authors)

Inflation with primordial broken power law spectrum as an alternative to the concordance cosmological model

International Nuclear Information System (INIS)

Pandolfi, Stefania; Giusarma, Elena; Lattanzi, Massimiliano; Melchiorri, Alessandro

2010-01-01

We consider cosmological models with a non-scale-invariant spectrum of primordial perturbations and assess whether they represent a viable alternative to the concordance ΛCDM model. We find that in the framework of a model selection analysis, the WMAP and 2dF data do not provide any conclusive evidence in favor of one or the other kind of model. However, when a marginalization over the entire space of nuisance parameters is performed, models with a modified primordial spectrum and Ω Λ =0 are strongly disfavored.

Measurement and model of the infrared two-photon emission spectrum of GaAs.

Science.gov (United States)

Hayat, Alex; Ginzburg, Pavel; Orenstein, Meir

2009-07-10

Two-photon emission from semiconductors was recently observed, but not fully interpreted. We develop a dressed-state model incorporating intraband scattering-related level broadening, yielding nondivergent emission rates. The spectrum calculations for high carrier concentrations including the time dependence of the screening buildup correspond well to our measured two-photon emission spectrum from GaAs.

Equations of motion for a spectrum-generating algebra: Lipkin-Meshkov-Glick model

International Nuclear Information System (INIS)

Rosensteel, G; Rowe, D J; Ho, S Y

2008-01-01

For a spectrum-generating Lie algebra, a generalized equations-of-motion scheme determines numerical values of excitation energies and algebra matrix elements. In the approach to the infinite particle number limit or, more generally, whenever the dimension of the quantum state space is very large, the equations-of-motion method may achieve results that are impractical to obtain by diagonalization of the Hamiltonian matrix. To test the method's effectiveness, we apply it to the well-known Lipkin-Meshkov-Glick (LMG) model to find its low-energy spectrum and associated generator matrix elements in the eigenenergy basis. When the dimension of the LMG representation space is 10 6 , computation time on a notebook computer is a few minutes. For a large particle number in the LMG model, the low-energy spectrum makes a quantum phase transition from a nondegenerate harmonic vibrator to a twofold degenerate harmonic oscillator. The equations-of-motion method computes critical exponents at the transition point

Distance Dependent Model for the Delay Power Spectrum of In-room Radio Channels

DEFF Research Database (Denmark)

Steinböck, Gerhard; Pedersen, Troels; Fleury, Bernard Henri

2013-01-01

A model based on experimental observations of the delay power spectrum in closed rooms is proposed. The model includes the distance between the transmitter and the receiver as a parameter which makes it suitable for range based radio localization. The experimental observations motivate the proposed...... model of the delay power spectrum with a primary (early) component and a reverberant component (tail). The primary component is modeled as a Dirac delta function weighted according to an inverse distance power law (d-n). The reverberant component is an exponentially decaying function with onset equal...... to the propagation time between transmitter and receiver. Its power decays exponentially with distance. The proposed model allows for the prediction of e.g. the path loss, mean delay, root mean squared (rms) delay spread, and kurtosis versus the distance. The model predictions are validated by measurements...

The theoretical foundations for size spectrum models of fish communities

DEFF Research Database (Denmark)

Andersen, Ken Haste; Jacobsen, Nis Sand; Farnsworth, K.D.

2016-01-01

Size spectrum models have emerged from 40 years of basic research on how body size determines individual physiology and structures marine communities. They are based on commonly accepted assumptions and have a low parameter set, which make them easy to deploy for strategic ecosystem oriented impact...... assessment of fisheries. We describe the fundamental concepts in size-based models about food encounter and the bioenergetics budget of individuals. Within the general framework three model types have emerged that differs in their degree of complexity: the food-web, the trait-based and the community model...

An ocean current inversion accuracy analysis based on a Doppler spectrum model

Institute of Scientific and Technical Information of China (English)

BAO Qingliu; ZHANG Youguang; LIN Mingsen; GONG Peng

2017-01-01

Microwave remote sensing is one of the most useful methods for observing the ocean parameters.The Doppler frequency or interferometric phase of the radar echoes can be used for an ocean surface current speed retrieval,which is widely used in spaceborne and airborne radars.While the effect of the ocean currents and waves is interactional.It is impossible to retrieve the ocean surface current speed from Doppler frequency shift directly.In order to study the relationship between the ocean surface current speed and the Doppler frequency shift,a numerical ocean surface Doppler spectrum model is established and validated with a reference.The input parameters of ocean Doppler spectrum include an ocean wave elevation model,a directional distribution function,and wind speed and direction.The suitable ocean wave elevation spectrum and the directional distribution function are selected by comparing the ocean Doppler spectrum in C band with an empirical geophysical model function (CDOP).What is more,the error sensitivities of ocean surface current speed to the wind speed and direction are analyzed.All these simulations are in Ku band.The simulation results show that the ocean surface current speed error is sensitive to the wind speed and direction errors.With VV polarization,the ocean surface current speed error is about 0.15 m/s when the wind speed error is 2 m/s,and the ocean surface current speed error is smaller than 0.3 m/s when the wind direction error is within 20° in the cross wind direction.

Microfluidic very large scale integration (VLSI) modeling, simulation, testing, compilation and physical synthesis

CERN Document Server

Pop, Paul; Madsen, Jan

2016-01-01

This book presents the state-of-the-art techniques for the modeling, simulation, testing, compilation and physical synthesis of mVLSI biochips. The authors describe a top-down modeling and synthesis methodology for the mVLSI biochips, inspired by microelectronics VLSI methodologies. They introduce a modeling framework for the components and the biochip architecture, and a high-level microfluidic protocol language. Coverage includes a topology graph-based model for the biochip architecture, and a sequencing graph to model for biochemical application, showing how the application model can be obtained from the protocol language. The techniques described facilitate programmability and automation, enabling developers in the emerging, large biochip market. · Presents the current models used for the research on compilation and synthesis techniques of mVLSI biochips in a tutorial fashion; · Includes a set of "benchmarks", that are presented in great detail and includes the source code of several of the techniques p...

Inapplicability of small-polaron model for the explanation of infrared absorption spectrum in acetanilide.

Science.gov (United States)

Zeković, Slobodan; Ivić, Zoran

2009-01-01

The applicability of small-polaron model for the interpretation of infrared absorption spectrum in acetanilide has been critically reexamined. It is shown that the energy difference between the normal and anomalous peak, calculated by means of small-polaron theory, displays pronounced temperature dependence which is in drastic contradiction with experiment. It is demonstrated that self-trapped states, which are recently suggested to explain theoretically the experimental absorption spectrum in protein, cannot cause the appearance of the peaks in absorption spectrum for acetanilide.

The precipitation synthesis of broad-spectrum UV absorber nanoceria

International Nuclear Information System (INIS)

Nurhasanah, Iis; Sutanto, Heri; Puspaningrum, Nurul Wahyu

2013-01-01

In this paper the possibility of nanoceria as broad-spectrum UV absorber was evaluated. Nanoceria were synthesized by precipitation process from cerium nitrate solution and ammonium hydroxide as precipitant agent. Isopropanol was mixed with water as solvent to prevent hard agglomeration. The structure of resulting nanoceria was characterized by x-ray diffractometer (XRD). The transparency in the visible light and efficiency of protection in UV A region were studied using ultraviolet-visible (UV - Vis) spectrophotometer. The results show that nanoceria possess good tranparency in visible light and high UV light absorption. The critical absorption wavelenght of 368 nm was obtained which is desirable for excellent broad-spectrum protection absorbers. Moreover, analysis of photodegradation nanoceria to methylene blue solution shows poor photocatalytic activity. It indicates that nanoceria suitable for used as UV absorber in personal care products

Modeling the Complete Gravitational Wave Spectrum of Neutron Star Mergers.

Science.gov (United States)

Bernuzzi, Sebastiano; Dietrich, Tim; Nagar, Alessandro

2015-08-28

In the context of neutron star mergers, we study the gravitational wave spectrum of the merger remnant using numerical relativity simulations. Postmerger spectra are characterized by a main peak frequency f2 related to the particular structure and dynamics of the remnant hot hypermassive neutron star. We show that f(2) is correlated with the tidal coupling constant κ(2)^T that characterizes the binary tidal interactions during the late-inspiral merger. The relation f(2)(κ(2)^T) depends very weakly on the binary total mass, mass ratio, equation of state, and thermal effects. This observation opens up the possibility of developing a model of the gravitational spectrum of every merger unifying the late-inspiral and postmerger descriptions.

The baryonic spectrum in a constituent quark model including a three-body force

International Nuclear Information System (INIS)

Desplanques, B.; Gignoux, C.; Silvestre-Brac, B.; Gonzalez, P.; Navarro, J.; Noguera, S.

1992-01-01

We analyze, within a non-relativistic quark model, the low energy part of the baryonic spectrum in the octet and decuplet flavour representations. The relevance of a strong Coulomb potential is emphasized in order to explain its general features. The addition of a three-body force allows to solve the 'Roper puzzle', giving a consistent explanation to its relative position in the spectrum. (orig.)

Full-Band Quasi-Harmonic Analysis and Synthesis of Musical Instrument Sounds with Adaptive Sinusoids

Directory of Open Access Journals (Sweden)

Marcelo Caetano

2016-05-01

Full Text Available Sinusoids are widely used to represent the oscillatory modes of musical instrument sounds in both analysis and synthesis. However, musical instrument sounds feature transients and instrumental noise that are poorly modeled with quasi-stationary sinusoids, requiring spectral decomposition and further dedicated modeling. In this work, we propose a full-band representation that fits sinusoids across the entire spectrum. We use the extended adaptive Quasi-Harmonic Model (eaQHM to iteratively estimate amplitude- and frequency-modulated (AM–FM sinusoids able to capture challenging features such as sharp attacks, transients, and instrumental noise. We use the signal-to-reconstruction-error ratio (SRER as the objective measure for the analysis and synthesis of 89 musical instrument sounds from different instrumental families. We compare against quasi-stationary sinusoids and exponentially damped sinusoids. First, we show that the SRER increases with adaptation in eaQHM. Then, we show that full-band modeling with eaQHM captures partials at the higher frequency end of the spectrum that are neglected by spectral decomposition. Finally, we demonstrate that a frame size equal to three periods of the fundamental frequency results in the highest SRER with AM–FM sinusoids from eaQHM. A listening test confirmed that the musical instrument sounds resynthesized from full-band analysis with eaQHM are virtually perceptually indistinguishable from the original recordings.

Synthesis and properties of Oxasmaragdyrins containing one Five ...

Indian Academy of Sciences (India)

pioneering synthesis of Vitamin B12.2a However, the first synthesis of .... 2.3b Compound 3: Yield 22% (135 mg); 1H NMR. (500 MHz, CDCl3, 25 .... (b). Figure 1. (a) 1H NMR and (b) 1H-1H COSY NMR spectrum of compound 4 recorded in CDCl3 at room temperature. The double crossed peak in (a) and an asterix marked ...

Enzymatic Synthesis of Ampicillin: Nonlinear Modeling, Kinetics Estimation, and Adaptive Control

Directory of Open Access Journals (Sweden)

Monica Roman

2012-01-01

Full Text Available Nowadays, the use of advanced control strategies in biotechnology is quite low. A main reason is the lack of quality of the data, and the fact that more sophisticated control strategies must be based on a model of the dynamics of bioprocesses. The nonlinearity of the bioprocesses and the absence of cheap and reliable instrumentation require an enhanced modeling effort and identification strategies for the kinetics. The present work approaches modeling and control strategies for the enzymatic synthesis of ampicillin that is carried out inside a fed-batch bioreactor. First, a nonlinear dynamical model of this bioprocess is obtained by using a novel modeling procedure for biotechnology: the bond graph methodology. Second, a high gain observer is designed for the estimation of the imprecisely known kinetics of the synthesis process. Third, by combining an exact linearizing control law with the on-line estimation kinetics algorithm, a nonlinear adaptive control law is designed. The case study discussed shows that a nonlinear feedback control strategy applied to the ampicillin synthesis bioprocess can cope with disturbances, noisy measurements, and parametric uncertainties. Numerical simulations performed with MATLAB environment are included in order to test the behavior and the performances of the proposed estimation and control strategies.

Hybrid Model of Inhomogeneous Solar Wind Plasma Heating by Alfven Wave Spectrum: Parametric Studies

Science.gov (United States)

Ofman, L.

2010-01-01

Observations of the solar wind plasma at 0.3 AU and beyond show that a turbulent spectrum of magnetic fluctuations is present. Remote sensing observations of the corona indicate that heavy ions are hotter than protons and their temperature is anisotropic (T(sub perpindicular / T(sub parallel) >> 1). We study the heating and the acceleration of multi-ion plasma in the solar wind by a turbulent spectrum of Alfvenic fluctuations using a 2-D hybrid numerical model. In the hybrid model the protons and heavy ions are treated kinetically as particles, while the electrons are included as neutralizing background fluid. This is the first two-dimensional hybrid parametric study of the solar wind plasma that includes an input turbulent wave spectrum guided by observation with inhomogeneous background density. We also investigate the effects of He++ ion beams in the inhomogeneous background plasma density on the heating of the solar wind plasma. The 2-D hybrid model treats parallel and oblique waves, together with cross-field inhomogeneity, self-consistently. We investigate the parametric dependence of the perpendicular heating, and the temperature anisotropy in the H+-He++ solar wind plasma. It was found that the scaling of the magnetic fluctuations power spectrum steepens in the higher-density regions, and the heating is channeled to these regions from the surrounding lower-density plasma due to wave refraction. The model parameters are applicable to the expected solar wind conditions at about 10 solar radii.

The business model impact of flexible spectrum management and cognitive networks

NARCIS (Netherlands)

Delaere, S.; Ballon, P.

2007-01-01

Purpose - This paper aims to give a short overview of European Union policy trends towards more flexible forms of spectrum management. Design/methodology/approach - The paper presents a business modelling analysis, scenario construction, policy analysis and roadmapping. It argues that both flexible

Anelastic deformation processes in metallic glasses and activation energy spectrum model

NARCIS (Netherlands)

Ocelik, [No Value; Csach, K; Kasardova, A; Bengus, VZ; Ocelik, Vaclav

1997-01-01

The isothermal kinetics of anelastic deformation below the glass transition temperature (so-called 'stress induced ordering' or 'creep recovery' deformation) was investigated in Ni-Si-B metallic glass. The relaxation time spectrum model and two recently developed methods for its calculation from the

Effects of near-ultraviolet and violet radiations (313-405 NM) on DNA, RNA, and protein synthesis in E. coli B/r

International Nuclear Information System (INIS)

Ramabhadran, T.V.

1975-01-01

Fluences (21 to 32 kJ/m 2 ) of near-ultraviolet radiation that induced about a 1 hour growth delay in continuously growing cultures of E.coli B/r were found to produce complete cessation of net RNA synthesis, while the effects on protein and DNA synthesis were considerably milder. The near-UV action spectrum for this inhibition of RNA synthesis was similar to the action spectrum for growth decay in E.coli B and to the absorption spectrum of E.coli valyl transfer RNA. In addition, the fluences required for inhibition of RNA synthesis and growth delay were similar to those reported for formation of 4-thiouridine-cytidine adducts in transfer RNA. These findings suggest that the chromophore and target for near-UV-induced inhibition of both net RNA synthesis and growth in E.coli may be 4-thiouridine in transfer RNA. (author)

Ground level enhancement (GLE) energy spectrum parameters model

Science.gov (United States)

Qin, G.; Wu, S.

2017-12-01

We study the ground level enhancement (GLE) events in solar cycle 23 with the four energy spectra parameters, the normalization parameter C, low-energy power-law slope γ 1, high-energy power-law slope γ 2, and break energy E0, obtained by Mewaldt et al. 2012 who fit the observations to the double power-law equation. we divide the GLEs into two groups, one with strong acceleration by interplanetary (IP) shocks and another one without strong acceleration according to the condition of solar eruptions. We next fit the four parameters with solar event conditions to get models of the parameters for the two groups of GLEs separately. So that we would establish a model of energy spectrum for GLEs for the future space weather prediction.

Controller Synthesis using Qualitative Models and Constraints

OpenAIRE

Ramamoorthy, Subramanian; Kuipers, Benjamin J

2004-01-01

Many engineering systems require the synthesis of global behaviors in nonlinear dynamical systems. Multiple model approaches to control design make it possible to synthesize robust and optimal versions of such global behaviors. We propose a methodology called Qualitative Heterogeneous Control that enables this type of control design. This methodology is based on a separation of concerns between qualitative correctness and quantitative optimization. Qualitative sufficient conditions are derive...

Instrument Modeling and Synthesis

Science.gov (United States)

Horner, Andrew B.; Beauchamp, James W.

During the 1970s and 1980s, before synthesizers based on direct sampling of musical sounds became popular, replicating musical instruments using frequency modulation (FM) or wavetable synthesis was one of the “holy grails” of music synthesis. Synthesizers such as the Yamaha DX7 allowed users great flexibility in mixing and matching sounds, but were notoriously difficult to coerce into producing sounds like those of a given instrument. Instrument design wizards practiced the mysteries of FM instrument design.

Food addiction spectrum: a theoretical model from normality to eating and overeating disorders.

Science.gov (United States)

Piccinni, Armando; Marazziti, Donatella; Vanelli, Federica; Franceschini, Caterina; Baroni, Stefano; Costanzo, Davide; Cremone, Ivan Mirko; Veltri, Antonello; Dell'Osso, Liliana

2015-01-01

The authors comment on the recently proposed food addiction spectrum that represents a theoretical model to understand the continuum between several conditions ranging from normality to pathological states, including eating disorders and obesity, as well as why some individuals show a peculiar attachment to food that can become an addiction. Further, they review the possible neurobiological underpinnings of these conditions that include dopaminergic neurotransmission and circuits that have long been implicated in drug addiction. The aim of this article is also that at stimulating a debate regarding the possible model of a food (or eating) addiction spectrum that may be helpful towards the search of novel therapeutic approaches to different pathological states related to disturbed feeding or overeating.

Model-based synthesis of locally contingent responses to global market signals

Science.gov (United States)

Magliocca, N. R.

2015-12-01

Rural livelihoods and the land systems on which they depend are increasingly influenced by distant markets through economic globalization. Place-based analyses of land and livelihood system sustainability must then consider both proximate and distant influences on local decision-making. Thus, advancing land change theory in the context of economic globalization calls for a systematic understanding of the general processes as well as local contingencies shaping local responses to global signals. Synthesis of insights from place-based case studies of land and livelihood change is a path forward for developing such systematic knowledge. This paper introduces a model-based synthesis approach to investigating the influence of local socio-environmental and agent-level factors in mediating land-use and livelihood responses to changing global market signals. A generalized agent-based modeling framework is applied to six case-study sites that differ in environmental conditions, market access and influence, and livelihood settings. The largest modeled land conversions and livelihood transitions to market-oriented production occurred in sties with relatively productive agricultural land and/or with limited livelihood options. Experimental shifts in the distributions of agents' risk tolerances generally acted to attenuate or amplify responses to changes in global market signals. Importantly, however, responses of agents at different points in the risk tolerance distribution varied widely, with the wealth gap growing wider between agents with higher or lower risk tolerance. These results demonstrate model-based synthesis is a promising approach to overcome many of the challenges of current synthesis methods in land change science, and to identify generalized as well as locally contingent responses to global market signals.

Ammonia synthesis and decomposition on a Ru-based catalyst modeled by first-principles

DEFF Research Database (Denmark)

Hellman, A.; Honkala, Johanna Karoliina; Remediakis, Ioannis

2009-01-01

A recently published first-principles model for the ammonia synthesis on an unpromoted Ru-based catalyst is extended to also describe ammonia decomposition. In addition, further analysis concerning trends in ammonia productivity, surface conditions during the reaction, and macro-properties, such ......A recently published first-principles model for the ammonia synthesis on an unpromoted Ru-based catalyst is extended to also describe ammonia decomposition. In addition, further analysis concerning trends in ammonia productivity, surface conditions during the reaction, and macro......-properties, such as apparent activation energies and reaction orders are provided. All observed trends in activity are captured by the model and the absolute value of ammonia synthesis/decomposition productivity is predicted to within a factor of 1-100 depending on the experimental conditions. Moreover it is shown: (i......) that small changes in the relative adsorption potential energies are sufficient to get a quantitative agreement between theory and experiment (Appendix A) and (ii) that it is possible to reproduce results from the first-principles model by a simple micro-kinetic model (Appendix B)....

Disrupted Cortical Connectivity as an Explanatory Model for Autism Spectrum Disorder

Directory of Open Access Journals (Sweden)

Jenniefer Drude Borup

2014-02-01

Full Text Available The aim of this article is to explain the theory of Disrupted Cortical Connectivity and discuss whether or not it can integrate the following three theories: Theory of Mind, Executive Functioning, and Weak Central Coherence that dominate the field of autism spectrum disorder research. Due to a lack of existing literature discussing this potential integration, we have consequentially undertaken such an endeavour. In our opinion, integration appears to be possible since this explanatory model can account for difficulties in both social cognition and executive functioning commonly found in autism spectrum disorder. Moreover, the theory of Disrupted Cortical Connectivity could be described as an extension of the theory of Weak Central Coherence.

[A Method to Reconstruct Surface Reflectance Spectrum from Multispectral Image Based on Canopy Radiation Transfer Model].

Science.gov (United States)

Zhao, Yong-guang; Ma, Ling-ling; Li, Chuan-rong; Zhu, Xiao-hua; Tang, Ling-li

2015-07-01

Due to the lack of enough spectral bands for multi-spectral sensor, it is difficult to reconstruct surface retlectance spectrum from finite spectral information acquired by multi-spectral instrument. Here, taking into full account of the heterogeneity of pixel from remote sensing image, a method is proposed to simulate hyperspectral data from multispectral data based on canopy radiation transfer model. This method first assumes the mixed pixels contain two types of land cover, i.e., vegetation and soil. The sensitive parameters of Soil-Leaf-Canopy (SLC) model and a soil ratio factor were retrieved from multi-spectral data based on Look-Up Table (LUT) technology. Then, by combined with a soil ratio factor, all the parameters were input into the SLC model to simulate the surface reflectance spectrum from 400 to 2 400 nm. Taking Landsat Enhanced Thematic Mapper Plus (ETM+) image as reference image, the surface reflectance spectrum was simulated. The simulated reflectance spectrum revealed different feature information of different surface types. To test the performance of this method, the simulated reflectance spectrum was convolved with the Landsat ETM + spectral response curves and Moderate Resolution Imaging Spectrometer (MODIS) spectral response curves to obtain the simulated Landsat ETM+ and MODIS image. Finally, the simulated Landsat ETM+ and MODIS images were compared with the observed Landsat ETM+ and MODIS images. The results generally showed high correction coefficients (Landsat: 0.90-0.99, MODIS: 0.74-0.85) between most simulated bands and observed bands and indicated that the simulated reflectance spectrum was well simulated and reliable.

Quantitative modeling of the third harmonic emission spectrum of plasmonic nanoantennas.

Science.gov (United States)

Hentschel, Mario; Utikal, Tobias; Giessen, Harald; Lippitz, Markus

2012-07-11

Plasmonic dimer nanoantennas are characterized by a strong enhancement of the optical field, leading to large nonlinear effects. The third harmonic emission spectrum thus depends strongly on the antenna shape and size as well as on its gap size. Despite the complex shape of the nanostructure, we find that for a large range of different geometries the nonlinear spectral properties are fully determined by the linear response of the antenna. We find excellent agreement between the measured spectra and predictions from a simple nonlinear oscillator model. We extract the oscillator parameters from the linear spectrum and use the amplitude of the nonlinear perturbation only as scaling parameter of the third harmonic spectra. Deviations from the model only occur for gap sizes below 20 nm, indicating that only for these small distances the antenna hot spot contributes noticeable to the third harmonic generation. Because of its simplicity and intuitiveness, our model allows for the rational design of efficient plasmonic nonlinear light sources and is thus crucial for the design of future plasmonic devices that give substantial enhancement of nonlinear processes such as higher harmonics generation as well as difference frequency mixing for plasmonically enhanced terahertz generation.

Scenarios and business models for mobile network operators utilizing the hybrid use concept of the UHF broadcasting spectrum

Directory of Open Access Journals (Sweden)

S. Yrjölä

2016-09-01

Full Text Available This paper explores and presents scenarios and business models for mobile network operators (MNOs in the novel hybrid use spectrum sharing concept of the Ultra High Frequency broadcasting spectrum (470-790 MHz used for Digital Terrestrial TV (DTT and Mobile Broadband (MBB. More flexible use of the band could lead to higher efficiency in delivering fast growing and converging MBB, media and TV content to meet changing consumer needs. On one hand, this could be beneficial for broadcasters (BC, e.g., by preserving the spectrum, by providing additional revenues, or by lowering cost of the spectrum and, on the other hand, for MNOs to gain faster access to new potentially lower cost, licensed, below 1GHz spectrum to cope with booming data traffic. As a collaborative benefit, the concept opens up new business opportunities for delivering TV and media content using MBB network with means to introduce this flexibly. This paper highlights the importance of developing sound business models for the new spectrum use concept, as they need to provide clear benefits to the key stakeholders to be adopted in real life. The paper applies a future and action oriented approach to the MBB using the concept to derive scenarios and business models for MNOs for accessing hybrid UHF bands. In order to address the convergence and transformation coming with the concept, business models are first developed for the current situation with separate exclusive spectrum bands. Novel business scenarios are then developed for the introduction of the new flexible hybrid UHF spectrum concept. The created business model indicates that the MNOs could benefit significantly from the new UHF bands, which would enable them to cope with increasing data traffic asymmetry, and to offer differentiation through personalized broadcasting and new media services. Moreover, it could significantly re-shape the business ecosystem around both the broadcasting and the mobile broadband by introducing

Does the Model Matter? Comparing Video Self-Modeling and Video Adult Modeling for Task Acquisition and Maintenance by Adolescents with Autism Spectrum Disorders

Science.gov (United States)

Cihak, David F.; Schrader, Linda

2009-01-01

The purpose of this study was to compare the effectiveness and efficiency of learning and maintaining vocational chain tasks using video self-modeling and video adult modeling instruction. Four adolescents with autism spectrum disorders were taught vocational and prevocational skills. Although both video modeling conditions were effective for…

Power spectrum model of visual masking: simulations and empirical data.

Science.gov (United States)

Serrano-Pedraza, Ignacio; Sierra-Vázquez, Vicente; Derrington, Andrew M

2013-06-01

In the study of the spatial characteristics of the visual channels, the power spectrum model of visual masking is one of the most widely used. When the task is to detect a signal masked by visual noise, this classical model assumes that the signal and the noise are previously processed by a bank of linear channels and that the power of the signal at threshold is proportional to the power of the noise passing through the visual channel that mediates detection. The model also assumes that this visual channel will have the highest ratio of signal power to noise power at its output. According to this, there are masking conditions where the highest signal-to-noise ratio (SNR) occurs in a channel centered in a spatial frequency different from the spatial frequency of the signal (off-frequency looking). Under these conditions the channel mediating detection could vary with the type of noise used in the masking experiment and this could affect the estimation of the shape and the bandwidth of the visual channels. It is generally believed that notched noise, white noise and double bandpass noise prevent off-frequency looking, and high-pass, low-pass and bandpass noises can promote it independently of the channel's shape. In this study, by means of a procedure that finds the channel that maximizes the SNR at its output, we performed numerical simulations using the power spectrum model to study the characteristics of masking caused by six types of one-dimensional noise (white, high-pass, low-pass, bandpass, notched, and double bandpass) for two types of channel's shape (symmetric and asymmetric). Our simulations confirm that (1) high-pass, low-pass, and bandpass noises do not prevent the off-frequency looking, (2) white noise satisfactorily prevents the off-frequency looking independently of the shape and bandwidth of the visual channel, and interestingly we proved for the first time that (3) notched and double bandpass noises prevent off-frequency looking only when the noise

Hadron spectrum in quenched lattice QCD and quark potential models

International Nuclear Information System (INIS)

Iwasaki, Y.; Yoshie, T.

1989-01-01

We show that the quenched lattice QCD gives a hadron spectrum which remarkably agrees with that of quark potential models for quark mass m q ≥ m strange , even when one uses the standard one-plaquette gauge action. This is contrary to what is stated in the literature. We clarify the reason of the discrepancy, paying close attention to systematic errors in numerical calculations. (orig.)

Mathematical Model of Synthesis Catalyst with Local Reaction Centers

Directory of Open Access Journals (Sweden)

I. V. Derevich

2017-01-01

Full Text Available The article considers a catalyst granule with a porous ceramic passive substrate and point active centers on which an exothermic synthesis reaction occurs. A rate of the chemical reaction depends on the temperature according to the Arrhenius law. Heat is removed from the pellet surface in products of synthesis due to heat transfer. In our work we first proposed a model for calculating the steady-state temperature of a catalyst pellet with local reaction centers. Calculation of active centers temperature is based on the idea of self-consistent field (mean-field theory. At first, it is considered that powers of the reaction heat release at the centers are known. On the basis of the found analytical solution, which describes temperature distribution inside the granule, the average temperature of the reaction centers is calculated, which then is inserted in the formula for heat release. The resulting system of transcendental algebraic equations is transformed into a system of ordinary differential equations of relaxation type and solved numerically to achieve a steady-state value. As a practical application, the article considers a Fischer-Tropsch synthesis catalyst granule with active cobalt metallic micro-particles. Cobalt micro-particles are the centers of the exothermic reaction of hydrocarbons macromolecular synthesis. Synthesis occurs as a result of absorption of the components of the synthesis gas on metallic cobalt. The temperature distribution inside the granule for a single local center and reaction centers located on the same granule diameter is found. It was found that there is a critical temperature of reactor exceeding of which leads to significant local overheating of the centers - thermal explosion. The temperature distribution with the local reaction centers is qualitatively different from the granule temperature, calculated in the homogeneous approximation. It is shown that, in contrast to the homogeneous approximation, the

Kinetic and thermodynamic modelling of TBP synthesis processes

International Nuclear Information System (INIS)

Azzouz, A.; Attou, M.

1989-02-01

The present paper deals with kinetic and thermodynamic modellisation of tributylphosphate (TBP) synthesis processes. Its aim consists in a purely comparative study of two different synthesis ways i.e. direct and indirect estirification of butanol. The methodology involves two steps. The first step consists in approximating curves which describe the process evolution and their dependence on the main parameters. The results gave a kinetic model of the process rate yielding in TBP. Further, on the basis of thermodynamic data concerning the various involved compounds a theoretical model was achieved. The calculations were carried out in Basic language and an interpolation mathematical method was applied to approximate the kinetic curves. The thermodynamic calculations were achieved on the basis of GIBBS' free energy using a VAX type computer and a VT240 terminal. The calculations accuracy was reasonable and within the norms. For each process, the confrontation of both models leads to an appreciable accord. In the two processes, the thermodynamic models were similar although the kinetic equations present different reaction orders. Hence the reaction orders were determined by a mathematical method which conists in searching the minimal difference between an empiric relation and a kinetic model with fixed order. This corresponds in fact in testing the model proposed at various reaction order around the suspected value. The main idea which results from such a work is that this kind of processes is well fitting with the model without taking into account the side chain reactions. The process behaviour is like that of a single reaction having a quasi linear dependence of the rate yielding and the reaction time for both processes

Synthesis and phosphatase activity of a Cobalt(II) phenanthroline ...

Indian Academy of Sciences (India)

MAMONI GARAI

2017-09-19

Sep 19, 2017 ... Synthesis and phosphatase activity of a Cobalt(II) phenanthroline complex. MAMONI GARAIa ... tion, cobalt complexes have gained importance because of their application as ... 2.3 Physical measurements. Infrared spectrum ...

Proton transport in a membrane protein channel: two-dimensional infrared spectrum modeling.

NARCIS (Netherlands)

Liang, C.; Knoester, J.; Jansen, T.L.Th.A.

2012-01-01

We model the two-dimensional infrared (2DIR) spectrum of a proton channel to investigate its applicability as a spectroscopy tool to study the proton transport process in biological systems. Proton transport processes in proton channels are involved in numerous fundamental biochemical reactions.

FT-IR spectrum of grape seed oil and quantum models of fatty acids triglycerides

Science.gov (United States)

Berezin, K. V.; Antonova, E. M.; Shagautdinova, I. T.; Chernavina, M. L.; Dvoretskiy, K. N.; Grechukhina, O. N.; Vasilyeva, L. M.; Rybakov, A. V.; Likhter, A. M.

2018-04-01

FT-IR spectra of grape seed oil and glycerol were registered in the 650-4000 cm-1 range. Molecular models of glycerol and some fatty acids that compose the oil under study - linoleic, oleic, palmitic and stearic acids - as well as their triglycerides were developed within B3LYP/6-31G(d) density functional model. A vibrating FT-IR spectrum of grape seed oil was modeled on the basis of calculated values of vibrating wave numbers and IR intensities of the fatty acids triglycerides and with regard to their percentage. Triglyceride spectral bands that were formed by glycerol linkage vibrations were revealed. It was identified that triglycerol linkage has a small impact on the structure of fatty acids and, consequently, on vibrating wave numbers. The conducted molecular modeling became a basis for theoretical interpretation on 10 experimentally observed absorption bands in FT-IR spectrum of grape seed oil.

Efficiently Synchronized Spread-Spectrum Audio Watermarking with Improved Psychoacoustic Model

Directory of Open Access Journals (Sweden)

Xing He

2008-01-01

Full Text Available This paper presents an audio watermarking scheme which is based on an efficiently synchronized spread-spectrum technique and a new psychoacoustic model computed using the discrete wavelet packet transform. The psychoacoustic model takes advantage of the multiresolution analysis of a wavelet transform, which closely approximates the standard critical band partition. The goal of this model is to include an accurate time-frequency analysis and to calculate both the frequency and temporal masking thresholds directly in the wavelet domain. Experimental results show that this watermarking scheme can successfully embed watermarks into digital audio without introducing audible distortion. Several common watermark attacks were applied and the results indicate that the method is very robust to those attacks.

Investigation on method of estimating the excitation spectrum of vibration source

International Nuclear Information System (INIS)

Zhang Kun; Sun Lei; Lin Song

2010-01-01

In practical engineer area, it is hard to obtain the excitation spectrum of the auxiliary machines of nuclear reactor through direct measurement. To solve this problem, the general method of estimating the excitation spectrum of vibration source through indirect measurement is proposed. First, the dynamic transfer matrix between the virtual excitation points and the measure points is obtained through experiment. The matrix combined with the response spectrum at the measure points under practical work condition can be used to calculate the excitation spectrum acts on the virtual excitation points. Then a simplified method is proposed which is based on the assumption that the vibration machine can be regarded as rigid body. The method treats the centroid as the excitation point and the dynamic transfer matrix is derived by using the sub structure mobility synthesis method. Thus, the excitation spectrum can be obtained by the inverse of the transfer matrix combined with the response spectrum at the measure points. Based on the above method, a computing example is carried out to estimate the excitation spectrum acts on the centroid of a electrical pump. By comparing the input excitation and the estimated excitation, the reliability of this method is verified. (authors)

A perturbative approach to the redshift space power spectrum: beyond the Standard Model

Energy Technology Data Exchange (ETDEWEB)

Bose, Benjamin; Koyama, Kazuya, E-mail: benjamin.bose@port.ac.uk, E-mail: kazuya.koyama@port.ac.uk [Institute of Cosmology and Gravitation, University of Portsmouth, Burnaby Road, Portsmouth, Hampshire, PO1 3FX (United Kingdom)

2016-08-01

We develop a code to produce the power spectrum in redshift space based on standard perturbation theory (SPT) at 1-loop order. The code can be applied to a wide range of modified gravity and dark energy models using a recently proposed numerical method by A.Taruya to find the SPT kernels. This includes Horndeski's theory with a general potential, which accommodates both chameleon and Vainshtein screening mechanisms and provides a non-linear extension of the effective theory of dark energy up to the third order. Focus is on a recent non-linear model of the redshift space power spectrum which has been shown to model the anisotropy very well at relevant scales for the SPT framework, as well as capturing relevant non-linear effects typical of modified gravity theories. We provide consistency checks of the code against established results and elucidate its application within the light of upcoming high precision RSD data.

A Statistical Model for Synthesis of Detailed Facial Geometry

OpenAIRE

Golovinskiy, Aleksey; Matusik, Wojciech; Pfister, Hanspeter; Rusinkiewicz, Szymon; Funkhouser, Thomas

2006-01-01

Detailed surface geometry contributes greatly to the visual realism of 3D face models. However, acquiring high-resolution face geometry is often tedious and expensive. Consequently, most face models used in games, virtual reality, or computer vision look unrealistically smooth. In this paper, we introduce a new statistical technique for the analysis and synthesis of small three-dimensional facial features, such as wrinkles and pores. We acquire high-resolution face geometry for people across ...

Computational method and system for modeling, analyzing, and optimizing DNA amplification and synthesis

Science.gov (United States)

Vandersall, Jennifer A.; Gardner, Shea N.; Clague, David S.

2010-05-04

A computational method and computer-based system of modeling DNA synthesis for the design and interpretation of PCR amplification, parallel DNA synthesis, and microarray chip analysis. The method and system include modules that address the bioinformatics, kinetics, and thermodynamics of DNA amplification and synthesis. Specifically, the steps of DNA selection, as well as the kinetics and thermodynamics of DNA hybridization and extensions, are addressed, which enable the optimization of the processing and the prediction of the products as a function of DNA sequence, mixing protocol, time, temperature and concentration of species.

Hydrothermal synthesis and characterisation of amine-templated ...

African Journals Online (AJOL)

Hydrothermal synthesis and characterisation of amine-templated metal phosphate framework. ... The complexes were thermally stable up to 3000C, after which the organic components starts decomposing. The solubility test in a wide spectrum of solvents (at room temperature) showed that the complexes were insoluble in ...

Effects of near-ultraviolet and violet radiations (313-405 NM) on DNA, RNA, and protein synthesis in E. coli B/r. Implications for growth delay

Energy Technology Data Exchange (ETDEWEB)

Ramabhadran, T V [Texas Univ., Dallas (USA). Inst. for Molecular Biology

1975-09-01

Fluences (21 to 32 kJ/m/sup 2/) of near-ultraviolet radiation that induced about a 1 hour growth delay in continuously growing cultures of E.coli B/r were found to produce complete cessation of net RNA synthesis, while the effects on protein and DNA synthesis were considerably milder. The near-UV action spectrum for this inhibition of RNA synthesis was similar to the action spectrum for growth decay in E.coli B and to the absorption spectrum of E.coli valyl transfer RNA. In addition, the fluences required for inhibition of RNA synthesis and growth delay were similar to those reported for formation of 4-thiouridine-cytidine adducts in transfer RNA. These findings suggest that the chromophore and target for near-UV-induced inhibition of both net RNA synthesis and growth in E.coli may be 4-thiouridine in transfer RNA.

The spectrum of massive excitations of 3d 3-state Potts model and universality

International Nuclear Information System (INIS)

Falcone, R.; Fiore, R.; Gravina, M.; Papa, A.

2007-01-01

We consider the mass spectrum of the 3d 3-state Potts model in the broken phase (a) near the second order Ising critical point in the temperature-magnetic field plane and (b) near the weakly first order transition point at zero magnetic field. In the case (a), we compare the mass spectrum with the prediction from universality of mass ratios in the 3d Ising class; in the case (b), we determine a mass ratio to be compared with the corresponding one in the spectrum of screening masses of the (3+1)d SU(3) pure gauge theory at finite temperature in the deconfined phase near the transition. The agreement in the comparison in the case (a) would represent a non-trivial test of validity of the conjecture of spectrum universality. A positive answer to the comparison in the case (b) would suggest the possibility to extend this conjecture to weakly first order phase transitions

Synthesis of graphene by MEVVA source ion implantation

International Nuclear Information System (INIS)

Ying, J.J.; Xiao, X.H.; Dai, Z.G.; Wu, W.; Li, W.Q.; Mei, F.; Cai, G.X.; Ren, F.; Jiang, C.Z.

2013-01-01

Ion implantation provides a new synthesis route for graphene, and few-layered graphene synthesis by ion implantation has been reported. Here we show the synthesis of a single layer of high-quality graphene by Metal Vapor Vacuum Arc (MEVVA) source ion implantation. Polycrystalline nickel and copper thin films are implanted with MEVVA source carbon ions at 40 kV, followed by high-temperature thermal annealing and quenching. A Raman spectrum is applied to probe the quality and thickness of the prepared graphene. A single layer of high-quality graphene is grown on the nickel films, but not on the copper films. The growth mechanisms on the nickel and copper films are explained. MEVVA source ion implantation has been widely applied in industrial applications, demonstrating that this synthesis method can be generalized for industrial production

A discourse model of affect for text-to-speech synthesis

CSIR Research Space (South Africa)

Schlunz, GI

2013-12-01

Full Text Available This paper introduces a model of affect to improve prosody in text-to-speech synthesis. It operates on the discourse level of text to predict the underlying linguistic factors that contribute towards emotional appraisal, rather than any particular...

Group Contribution Based Process Flowsheet Synthesis, Design and Modelling

DEFF Research Database (Denmark)

d'Anterroches, Loïc; Gani, Rafiqul

2004-01-01

This paper presents a process-group-contribution Method to model. simulate and synthesize a flowsheet. The process-group based representation of a flowsheet together with a process "property" model are presented. The process-group based synthesis method is developed on the basis of the computer...... aided molecular design methods and gives the ability to screen numerous process alternatives without the need to use the rigorous process simulation models. The process "property" model calculates the design targets for the generated flowsheet alternatives while a reverse modelling method (also...... developed) determines the design variables matching the target. A simple illustrative example highlighting the main features of the methodology is also presented....

Bourbaki's structure theory in the problem of complex systems simulation models synthesis and model-oriented programming

Science.gov (United States)

Brodsky, Yu. I.

2015-01-01

The work is devoted to the application of Bourbaki's structure theory to substantiate the synthesis of simulation models of complex multicomponent systems, where every component may be a complex system itself. An application of the Bourbaki's structure theory offers a new approach to the design and computer implementation of simulation models of complex multicomponent systems—model synthesis and model-oriented programming. It differs from the traditional object-oriented approach. The central concept of this new approach and at the same time, the basic building block for the construction of more complex structures is the concept of models-components. A model-component endowed with a more complicated structure than, for example, the object in the object-oriented analysis. This structure provides to the model-component an independent behavior-the ability of standard responds to standard requests of its internal and external environment. At the same time, the computer implementation of model-component's behavior is invariant under the integration of models-components into complexes. This fact allows one firstly to construct fractal models of any complexity, and secondly to implement a computational process of such constructions uniformly-by a single universal program. In addition, the proposed paradigm allows one to exclude imperative programming and to generate computer code with a high degree of parallelism.

Models of Sexual and Relational Orientation: A Critical Review and Synthesis

Science.gov (United States)

Moe, Jeffry L.; Reicherzer, Stacee; Dupuy, Paula J.

2011-01-01

Many frameworks exist to explain and describe the phenomenon of same-sex sexuality as it applies to human development. This conceptual article provides a critical overview and synthesis of previous models to serve as a theoretical bridge for the suggested multiple continua model of sexual and relational orientations. Recommendations for how…

Serotonin synthesis, release and reuptake in terminals: a mathematical model

Directory of Open Access Journals (Sweden)

Best Janet

2010-08-01

Full Text Available Abstract Background Serotonin is a neurotransmitter that has been linked to a wide variety of behaviors including feeding and body-weight regulation, social hierarchies, aggression and suicidality, obsessive compulsive disorder, alcoholism, anxiety, and affective disorders. Full understanding of serotonergic systems in the central nervous system involves genomics, neurochemistry, electrophysiology, and behavior. Though associations have been found between functions at these different levels, in most cases the causal mechanisms are unknown. The scientific issues are daunting but important for human health because of the use of selective serotonin reuptake inhibitors and other pharmacological agents to treat disorders in the serotonergic signaling system. Methods We construct a mathematical model of serotonin synthesis, release, and reuptake in a single serotonergic neuron terminal. The model includes the effects of autoreceptors, the transport of tryptophan into the terminal, and the metabolism of serotonin, as well as the dependence of release on the firing rate. The model is based on real physiology determined experimentally and is compared to experimental data. Results We compare the variations in serotonin and dopamine synthesis due to meals and find that dopamine synthesis is insensitive to the availability of tyrosine but serotonin synthesis is sensitive to the availability of tryptophan. We conduct in silico experiments on the clearance of extracellular serotonin, normally and in the presence of fluoxetine, and compare to experimental data. We study the effects of various polymorphisms in the genes for the serotonin transporter and for tryptophan hydroxylase on synthesis, release, and reuptake. We find that, because of the homeostatic feedback mechanisms of the autoreceptors, the polymorphisms have smaller effects than one expects. We compute the expected steady concentrations of serotonin transporter knockout mice and compare to

Modelling redshift space distortion in the post-reionization H I 21-cm power spectrum

Science.gov (United States)

Sarkar, Debanjan; Bharadwaj, Somnath

2018-05-01

The post-reionization H I 21-cm signal is an excellent candidate for precision cosmology, this however requires accurate modelling of the expected signal. Sarkar et al. have simulated the real space H I 21-cm signal and have modelled the H I power spectrum as P_{{H I}}(k)=b^2 P(k), where P(k) is the dark matter power spectrum and b(k) is a (possibly complex) scale-dependent bias for which fitting formulas have been provided. This paper extends these simulations to incorporate redshift space distortion and predicts the expected redshift space H I 21-cm power spectrum P^s_{{H I}}(k_{\\perp },k_{allel }) using two different prescriptions for the H I distributions and peculiar velocities. We model P^s_{{H I}}(k_{\\perp },k_{allel }), assuming that it is the product of P_{{H I}}(k)=b^2 P(k) with a Kaiser enhancement term and a Finger of God (FoG) damping which has σp the pair velocity dispersion as a free parameter. Considering several possibilities for the bias and the damping profile, we find that the models with a scale-dependent bias and a Lorentzian damping profile best fit the simulated P^s_{{H I}}(k_{\\perp },k_{allel }) over the entire range 1 ≤ z ≤ 6. The best-fitting value of σp falls approximately as (1 + z)-m with m = 2 and 1.2, respectively, for the two different prescriptions. The model predictions are consistent with the simulations for k models underpredict P^s_2(k) at large k, and the fit is restricted to k < 0.15 Mpc-1.

Mathematical modelling of enzyme synthesis during fermentations: the Q-functions

Energy Technology Data Exchange (ETDEWEB)

Nielsen, H K; Martiny, S C

1981-01-01

In modeling enzyme synthesis, the Q-function has been generalized to describe ordinary induction and repression as well as mixed induction-repression. The practical use of the Q-function as found in the literature was considered, especially the implications of applying fractional exponents.

Steady Modeling for an Ammonia Synthesis Reactor Based on a Novel CDEAS-LS-SVM Model

Directory of Open Access Journals (Sweden)

Zhuoqian Liu

2014-01-01

Full Text Available A steady-state mathematical model is built in order to represent plant behavior under stationary operating conditions. A novel modeling using LS-SVR based on Cultural Differential Evolution with Ant Search is proposed. LS-SVM is adopted to establish the model of the net value of ammonia. The modeling method has fast convergence speed and good global adaptability for identification of the ammonia synthesis process. The LS-SVR model was established using the above-mentioned method. Simulation results verify the validity of the method.

The marine diversity spectrum

DEFF Research Database (Denmark)

Reuman, Daniel C.; Gislason, Henrik; Barnes, Carolyn

2014-01-01

of taxonomy (all the species in a region regardless of clade) are much less studied but are equally important and will illuminate a different set of ecological and evolutionary processes. We develop and test a mechanistic model of how diversity varies with body mass in marine ecosystems. The model predicts...... the form of the diversity spectrum', which quantifies the distribution of species' asymptotic body masses, is a species analogue of the classic size spectrum of individuals, and which we have found to be a new and widely applicable description of diversity patterns. The marine diversity spectrum...... is predicted to be approximately linear across an asymptotic mass range spanning seven orders of magnitude. Slope -0 center dot 5 is predicted for the global marine diversity spectrum for all combined pelagic zones of continental shelf seas, and slopes for large regions are predicted to lie between -0 center...

Real-Time Gesture-Controlled Physical Modelling Music Synthesis with Tactile Feedback

Directory of Open Access Journals (Sweden)

David M. Howard

2004-06-01

Full Text Available Electronic sound synthesis continues to offer huge potential possibilities for the creation of new musical instruments. The traditional approach is, however, seriously limited in that it incorporates only auditory feedback and it will typically make use of a sound synthesis model (e.g., additive, subtractive, wavetable, and sampling that is inherently limited and very often nonintuitive to the musician. In a direct attempt to challenge these issues, this paper describes a system that provides tactile as well as acoustic feedback, with real-time synthesis that invokes a more intuitive response from players since it is based upon mass-spring physical modelling. Virtual instruments are set up via a graphical user interface in terms of the physical properties of basic well-understood sounding objects such as strings, membranes, and solids. These can be interconnected to form complex integrated structures. Acoustic excitation can be applied at any point mass via virtual bowing, plucking, striking, specified waveform, or from any external sound source. Virtual microphones can be placed at any point masses to deliver the acoustic output. These aspects of the instrument are described along with the nature of the resulting acoustic output.

Cholesterol metabolism: use of D2O for determination of synthesis rate in cell culture

International Nuclear Information System (INIS)

Esterman, A.L.; Cohen, B.I.; Javitt, N.B.

1985-01-01

Cholesterol synthesis in cell culture in the presence of D 2 O yields a spectrum of enriched molecules having a relative abundance that indicates random substitution of deuterium for hydrogen. Quantitation of the absolute rate of cholesterol synthesis is obtained by isotope ratio mass spectrometry. Mevinolin and 26-hydroxycholesterol both decrease cholesterol synthesis rate but have a discordant effect on HMG-CoA reductase activity

Video Modeling: A Visually Based Intervention for Children with Autism Spectrum Disorder

Science.gov (United States)

Ganz, Jennifer B.; Earles-Vollrath, Theresa L.; Cook, Katherine E.

2011-01-01

Visually based interventions such as video modeling have been demonstrated to be effective with students with autism spectrum disorder (ASD). This approach has wide utility, is appropriate for use with students of a range of ages and abilities, promotes independent functioning, and can be used to address numerous learner objectives, including…

The theoretical study of full spectrum analysis method for airborne gamma-ray spectrometric data

International Nuclear Information System (INIS)

Ni Weichong

2011-01-01

Spectra of airborne gamma-ray spectrometry was found to be the synthesis of spectral components of radioelement sources by analyzing the constitution of radioactive sources for airborne gamma-ray spectrometric survey and establishing the models of gamma-ray measurement. The mathematical equation for analysising airborne gamma-ray full spectrometric data can be expressed into matrix and related expansions were developed for the mineral resources exploration, environmental radiation measurement, nuclear emergency monitoring, and so on. Theoretical study showed that the atmospheric radon could be directly computed by airborne gamma-ray spectrometric data with full spectrum analysis without the use of the accessional upward-looking detectors. (authors)

Thermodynamic models to predict gas-liquid solubilities in the methanol synthesis, the methanol-higher alcohol synthesis, and the Fischer-Tropsch synthesis via gas-slurry processes

NARCIS (Netherlands)

Breman, B.B; Beenackers, A.A C M

1996-01-01

Various thermodynamic models were tested concerning their applicability to predict gas-liquid solubilities, relevant for synthesis gas conversion to methanol, higher alcohols, and hydrocarbons via gas-slurry processes. Without any parameter optimization the group contribution equation of state

Effects of virtual isobar admixtures on the low-energy spectrum of a complex nucleus - model calculations for 12C

International Nuclear Information System (INIS)

Grecksch, E.

1978-01-01

On the basis of a detailed analysis of the excitation spectrum of a complex nucleus in the framework of the conventional shell model theory, the paper extends this concept by adding nucleonic degrees of freedom (isobars) and by model investigations and a realistic assessment of their effects on the excited states of the low-energy spectrum. (AH) [de

A probabilistic model for component-based shape synthesis

KAUST Repository

Kalogerakis, Evangelos

2012-07-01

We present an approach to synthesizing shapes from complex domains, by identifying new plausible combinations of components from existing shapes. Our primary contribution is a new generative model of component-based shape structure. The model represents probabilistic relationships between properties of shape components, and relates them to learned underlying causes of structural variability within the domain. These causes are treated as latent variables, leading to a compact representation that can be effectively learned without supervision from a set of compatibly segmented shapes. We evaluate the model on a number of shape datasets with complex structural variability and demonstrate its application to amplification of shape databases and to interactive shape synthesis. © 2012 ACM 0730-0301/2012/08-ART55.

Does the Spectrum model accurately predict trends in adult mortality? Evaluation of model estimates using empirical data from a rural HIV community cohort study in north-western Tanzania

Directory of Open Access Journals (Sweden)

Denna Michael

2014-01-01

Full Text Available Introduction: Spectrum epidemiological models are used by UNAIDS to provide global, regional and national HIV estimates and projections, which are then used for evidence-based health planning for HIV services. However, there are no validations of the Spectrum model against empirical serological and mortality data from populations in sub-Saharan Africa. Methods: Serologic, demographic and verbal autopsy data have been regularly collected among over 30,000 residents in north-western Tanzania since 1994. Five-year age-specific mortality rates (ASMRs per 1,000 person years and the probability of dying between 15 and 60 years of age (45Q15, were calculated and compared with the Spectrum model outputs. Mortality trends by HIV status are shown for periods before the introduction of antiretroviral therapy (1994–1999, 2000–2005 and the first 5 years afterwards (2005–2009. Results: Among 30–34 year olds of both sexes, observed ASMRs per 1,000 person years were 13.33 (95% CI: 10.75–16.52 in the period 1994–1999, 11.03 (95% CI: 8.84–13.77 in 2000–2004, and 6.22 (95% CI; 4.75–8.15 in 2005–2009. Among the same age group, the ASMRs estimated by the Spectrum model were 10.55, 11.13 and 8.15 for the periods 1994–1999, 2000–2004 and 2005–2009, respectively. The cohort data, for both sexes combined, showed that the 45Q15 declined from 39% (95% CI: 27–55% in 1994 to 22% (95% CI: 17–29% in 2009, whereas the Spectrum model predicted a decline from 43% in 1994 to 37% in 2009. Conclusion: From 1994 to 2009, the observed decrease in ASMRs was steeper in younger age groups than that predicted by the Spectrum model, perhaps because the Spectrum model under-estimated the ASMRs in 30–34 year olds in 1994–99. However, the Spectrum model predicted a greater decrease in 45Q15 mortality than observed in the cohort, although the reasons for this over-estimate are unclear.

Facile one-pot synthesis of functionalized organophosphonate ...

Indian Academy of Sciences (India)

WINTEC

The reaction of phosphorus trichloride with 2,6-diisopropyl phenol in the presence of LiCl under reflux ... on a Perkin Elmer Spectrum One FT–IR spectrometer. Microanalyses were performed on a Thermo Finni- gan (FLASH EA .... 3.1 Synthesis and characterization .... and no other signals corresponding to the formation.

Primordial power spectrum features and consequences

Science.gov (United States)

Goswami, G.

2014-03-01

The present Cosmic Microwave Background (CMB) temperature and polarization anisotropy data is consistent with not only a power law scalar primordial power spectrum (PPS) with a small running but also with the scalar PPS having very sharp features. This has motivated inflationary models with such sharp features. Recently, even the possibility of having nulls in the power spectrum (at certain scales) has been considered. The existence of these nulls has been shown in linear perturbation theory. What shall be the effect of higher order corrections on such nulls? Inspired by this question, we have attempted to calculate quantum radiative corrections to the Fourier transform of the 2-point function in a toy field theory and address the issue of how these corrections to the power spectrum behave in models in which the tree-level power spectrum has a sharp dip (but not a null). In particular, we have considered the possibility of the relative enhancement of radiative corrections in a model in which the tree-level spectrum goes through a dip in power at a certain scale. The mode functions of the field (whose power spectrum is to be evaluated) are chosen such that they undergo the kind of dynamics that leads to a sharp dip in the tree level power spectrum. Next, we have considered the situation in which this field has quartic self interactions, and found one loop correction in a suitably chosen renormalization scheme. Thus, we have attempted to answer the following key question in the context of this toy model (which is as important in the realistic case): In the chosen renormalization scheme, can quantum radiative corrections be enhanced relative to tree-level power spectrum at scales, at which sharp dips appear in the tree-level spectrum?

Model of the synthesis of trisporic acid in Mucorales showing bistability.

Science.gov (United States)

Werner, S; Schroeter, A; Schimek, C; Vlaic, S; Wöstemeyer, J; Schuster, S

2012-12-01

An important substance in the signalling between individuals of Mucor-like fungi is trisporic acid (TA). This compound, together with some of its precursors, serves as a pheromone in mating between (+)- and (-)-mating types. Moreover, intermediates of the TA pathway are exchanged between the two mating partners. Based on differential equations, mathematical models of the synthesis pathways of TA in the two mating types of an idealised Mucor-fungus are here presented. These models include the positive feedback of TA on its own synthesis. The authors compare three sub-models in view of bistability, robustness and the reversibility of transitions. The proposed modelling study showed that, in a system where intermediates are exchanged, a reversible transition between the two stable steady states occurs, whereas an exchange of the end product leads to an irreversible transition. The reversible transition is physiologically favoured, because the high-production state of TA must come to an end eventually. Moreover, the exchange of intermediates and TA is compared with the 3-way handshake widely used by computers linked in a network.

Population Synthesis Models for Normal Galaxies with Dusty Disks

Directory of Open Access Journals (Sweden)

Kyung-Won Suh

2003-09-01

Full Text Available To investigate the SEDs of galaxies considering the dust extinction processes in the galactic disks, we present the population synthesis models for normal galaxies with dusty disks. We use PEGASE (Fioc & Rocca-Volmerange 1997 to model them with standard input parameters for stars and new dust parameters. We find that the model results are strongly dependent on the dust parameters as well as other parameters (e.g. star formation history. We compare the model results with the observations and discuss about the possible explanations. We find that the dust opacity functions derived from studies of asymptotic giant branch stars are useful for modeling a galaxy with a dusty disk.

Application of flexible multibody modelling for control synthesis in mechatronics

NARCIS (Netherlands)

Aarts, Ronald G.K.M.; van Dijk, Johannes; Brouwer, Dannis Michel; Jonker, Jan B.; Samin, J.C.; Fisette, P.

2011-01-01

The models used in the conceptual phase of the mechatronic design should not be too complicated, yet they should capture the dominant system behaviour. This includes the computation of natural frequencies and mode shapes in a relevant frequency range. For the control system synthesis the low

The quark mass spectrum in the Universal Seesaw model

International Nuclear Information System (INIS)

Ranfone, S.

1993-03-01

In the context of a Universal Seesaw model implemented in a left-right symmetric theory, we show that, by allowing the two left-handed doublet Higgs fields to develop different vacuum-expectation-values (VEV's), it is possible to account for the observed structure of the quark mass spectrum without the need of any hierarchy among the Yukawa couplings. In this framework the top-quark mass is expected to be of the order of its present experimental lower bound, m t ≅ 90 to 100 GeV. Moreover, we find that, while one of the Higgs doublets gets essentially the standard model VEV of approximately 250 GeV, the second doublet is expected to have a much smaller VEV, of order 10 GeV. The identification of the large mass scale of the model with the Peccei-Quinn scale fixes the mass of the right-handed gauge bosons in the range 10 7 to 10 10 GeV, far beyond the reach of present collider experiments. (author)

Sound Synthesis of the Harpsichord Using a Computationally Efficient Physical Model

Science.gov (United States)

Välimäki, Vesa; Penttinen, Henri; Knif, Jonte; Laurson, Mikael; Erkut, Cumhur

2004-12-01

A sound synthesis algorithm for the harpsichord has been developed by applying the principles of digital waveguide modeling. A modification to the loss filter of the string model is introduced that allows more flexible control of decay rates of partials than is possible with a one-pole digital filter, which is a usual choice for the loss filter. A version of the commuted waveguide synthesis approach is used, where each tone is generated with a parallel combination of the string model and a second-order resonator that are excited with a common excitation signal. The second-order resonator, previously proposed for this purpose, approximately simulates the beating effect appearing in many harpsichord tones. The characteristic key-release thump terminating harpsichord tones is reproduced by triggering a sample that has been extracted from a recording. A digital filter model for the soundboard has been designed based on recorded bridge impulse responses of the harpsichord. The output of the string models is injected in the soundboard filter that imitates the reverberant nature of the soundbox and, particularly, the ringing of the short parts of the strings behind the bridge.

Sound Synthesis of the Harpsichord Using a Computationally Efficient Physical Model

Directory of Open Access Journals (Sweden)

Knif Jonte

2004-01-01

Full Text Available A sound synthesis algorithm for the harpsichord has been developed by applying the principles of digital waveguide modeling. A modification to the loss filter of the string model is introduced that allows more flexible control of decay rates of partials than is possible with a one-pole digital filter, which is a usual choice for the loss filter. A version of the commuted waveguide synthesis approach is used, where each tone is generated with a parallel combination of the string model and a second-order resonator that are excited with a common excitation signal. The second-order resonator, previously proposed for this purpose, approximately simulates the beating effect appearing in many harpsichord tones. The characteristic key-release thump terminating harpsichord tones is reproduced by triggering a sample that has been extracted from a recording. A digital filter model for the soundboard has been designed based on recorded bridge impulse responses of the harpsichord. The output of the string models is injected in the soundboard filter that imitates the reverberant nature of the soundbox and, particularly, the ringing of the short parts of the strings behind the bridge.

Synthesis and properties of porous zeolite aluminosilicate adsorbents

International Nuclear Information System (INIS)

Shilina, A.S.; Milinchuk, V.K.; Burukhin, S.B.; Gordienko, A.B.

2015-01-01

Environmentally safe non-energy-intensive methods of the synthesis have been developed and the properties of solid inorganic nanostructured zeolite-like adsorbents of a broad spectrum have been studied. The sorption capacities of the adsorbents with respect to various components of water pollution have been determined [ru

Bottomonium spectrum revisited

CERN Document Server

Segovia, Jorge; Entem, David R.; Fernández, Francisco

2016-01-01

We revisit the bottomonium spectrum motivated by the recently exciting experimental progress in the observation of new bottomonium states, both conventional and unconventional. Our framework is a nonrelativistic constituent quark model which has been applied to a wide range of hadronic observables from the light to the heavy quark sector and thus the model parameters are completely constrained. Beyond the spectrum, we provide a large number of electromagnetic, strong and hadronic decays in order to discuss the quark content of the bottomonium states and give more insights about the better way to determine their properties experimentally.

Incorporating Video Modeling into a School-Based Intervention for Students with Autism Spectrum Disorders

Science.gov (United States)

Wilson, Kaitlyn P.

2013-01-01

Purpose: Video modeling is an intervention strategy that has been shown to be effective in improving the social and communication skills of students with autism spectrum disorders, or ASDs. The purpose of this tutorial is to outline empirically supported, step-by-step instructions for the use of video modeling by school-based speech-language…

Visual Representation in GENESIS as a tool for Physical Modeling, Sound Synthesis and Musical Composition

OpenAIRE

Villeneuve, Jérôme; Cadoz, Claude; Castagné, Nicolas

2015-01-01

The motivation of this paper is to highlight the importance of visual representations for artists when modeling and simulating mass-interaction physical networks in the context of sound synthesis and musical composition. GENESIS is a musician-oriented software environment for sound synthesis and musical composition. However, despite this orientation, a substantial amount of effort has been put into building a rich variety of tools based on static or dynamic visual representations of models an...

Modeling the absorption spectrum of the permanganate ion in vacuum and in aqueous solution

Science.gov (United States)

Olsen, Jógvan Magnus Haugaard; Hedegård, Erik Donovan

The absorption spectrum of the MnO$_{4}$$^{-}$ ion has been a test-bed for quantum-chemical methods over the last decades. Its correct description requires highly-correlated multiconfigurational methods, which are incompatible with the inclusion of finite-temperature and solvent effects due to their high computational demands. Therefore, implicit solvent models are usually employed. Here we show that implicit solvent models are not sufficiently accurate to model the solvent shift of MnO$_{4}$$^{-}$, and we analyze the origins of their failure. We obtain the correct solvent shift for MnO$_{4}$$^{-}$ in aqueous solution by employing the polarizable embedding (PE) model combined with a range-separated complete active space short-range density functional theory method (CAS-srDFT). Finite-temperature effects are taken into account by averaging over structures obtained from ab initio molecular dynamics simulations. The explicit treatment of finite-temperature and solvent effects facilitates the interpretation of the bands in the low-energy region of the MnO$_{4}$$^{-}$ absorption spectrum, whose assignment has been elusive.

Model studies of methanol synthesis on copper catalysts

Energy Technology Data Exchange (ETDEWEB)

Nakamura, J.; Nakamura, I.; Uchijima, T. [Univ. of Tsukuba, Ibaraki (Japan); Watanabe, T. [Research Inst. of Innovative Technology for Earth, Kyoto (Japan); Fujitani, T. [National Inst. for Resources and Environment, Ibaraki (Japan)

1996-12-31

The synthesis of methanol by the hydrogenation of CO{sub 2} over Zn-deposited and Zn-free copper surfaces has been studied using an XPS apparatus combined with a high-pressure flow reactor (18 atm). It was shown that the Zn deposited on Cu(111) and poly-Cu acted as a promoter for methanol synthesis, while the Zn on Cu(110) and Cu(100) had no such a promotional effect. The turnover frequency (TOF) for Zn/Cu(111) linearly increased with Zn coverage below {Theta}Zn--0.19, and then decreased above {Theta}Zn=0.20. The optimum TOF obtained at {Theta}Zn--0-19 was thirteen-fold larger than TOF for the Zn-free Cu(111) surface. On the other hand, no promotional effect of Zn was observed for the reverse water-gas shift reaction on all the surfaces. The results indicate the formation of special sites for methanol synthesis on Zn/Cu(111). The Zn-deposited Cu(111) can be regarded as a model of Cu/ZnO catalysts because the TOF and the activation energy for methanol formation over the Zn-deposited Cu(111) were in fairly good agreement with those for the Cu/ZnO powder catalysts. The post-reaction surface analysis by XPS showed the formation of formate species (HCOOa). The formate coverage was proportional to the activity for methanol formation below {Theta}Zn=0.20, suggesting that the hydrogenation of the formate species is the rate-determining step of methanol formation. The formate species was stabilized by Zn species on Cu(111) in the absence of ZnO species. STM results on the Zn-deposited Cu(111) suggested the formation of a Cu-Zn surface alloy. The presence of special sites for methanol synthesis was also indicated in the results of powder catalysts.

How do leaf veins influence the worldwide leaf economic spectrum? Review and synthesis.

Science.gov (United States)

Sack, Lawren; Scoffoni, Christine; John, Grace P; Poorter, Hendrik; Mason, Chase M; Mendez-Alonzo, Rodrigo; Donovan, Lisa A

2013-10-01

Leaf vein traits are implicated in the determination of gas exchange rates and plant performance. These traits are increasingly considered as causal factors affecting the 'leaf economic spectrum' (LES), which includes the light-saturated rate of photosynthesis, dark respiration, foliar nitrogen concentration, leaf dry mass per area (LMA) and leaf longevity. This article reviews the support for two contrasting hypotheses regarding a key vein trait, vein length per unit leaf area (VLA). Recently, Blonder et al. (2011, 2013) proposed that vein traits, including VLA, can be described as the 'origin' of the LES by structurally determining LMA and leaf thickness, and thereby vein traits would predict LES traits according to specific equations. Careful re-examination of leaf anatomy, published datasets, and a newly compiled global database for diverse species did not support the 'vein origin' hypothesis, and moreover showed that the apparent power of those equations to predict LES traits arose from circularity. This review provides a 'flux trait network' hypothesis for the effects of vein traits on the LES and on plant performance, based on a synthesis of the previous literature. According to this hypothesis, VLA, while virtually independent of LMA, strongly influences hydraulic conductance, and thus stomatal conductance and photosynthetic rate. We also review (i) the specific physiological roles of VLA; (ii) the role of leaf major veins in influencing LES traits; and (iii) the role of VLA in determining photosynthetic rate per leaf dry mass and plant relative growth rate. A clear understanding of leaf vein traits provides a new perspective on plant function independently of the LES and can enhance the ability to explain and predict whole plant performance under dynamic conditions, with applications towards breeding improved crop varieties.

Effect of reducing conditions of synthesis on the character of the crystallization of phosphate glasses

Energy Technology Data Exchange (ETDEWEB)

Alekseeva, I.P.; Karapetyan, G.O.; Milyukov, E.M.; Rusan, V.V.

1986-03-01

The authors investigate the effect of synthesis conditions on the properties of phosphate glasses with a high concentration of rare-earth elements (REE) which are promising materials for quantum electronics. Particular attention was paid to the character of the crystallization of the glasses. A model glass of the composition La/sub 2/O/sub 3/ X 3P/sub 2/O/sub 5/ was studied which is transparent in the visible and near-IR regions of the spectrum and produced commercially.

Ultraviolet spectrum of the planetary nebulae NGC 7662 observations and models

Energy Technology Data Exchange (ETDEWEB)

Pena, M; Torres-Peimbert, S [Universidad Nacional Autonoma de Mexico, Mexico City. Inst. de Astronomia

1981-01-01

We present IUE observations of emission lines in the spectrum of NGC 7662 in the 1150-3300 A range. Combining these observations with optical data obtained by other authors, we derive the chemical composition for this object. We obtain log C = -3.07, log N = -3.73, log O = -3.09 and log Ne = -3.70. We compute models of ionization structure and thermal balance to compare with the observed data.

On the high energy gamma ray spectrum and the particle production model

International Nuclear Information System (INIS)

Ohta, Itaru; Tezuka, Ikuo.

1979-01-01

A small emulsion chamber, 25 cm x 20 cm in area and 12 radiation lengths in thick, was exposed with JAL jet-cargo at an atmospheric depth of 260 g/cm 2 during 150 hrs. The gamma ray spectrum derived by combining data from X-ray films and nuclear emulsions is well represented by I sub(r) (>=Er) = (3.65 +- 0.30) x 10 -8 [E sub(r)/TeV]sup(-1.89+0.06-0.09)/cm 2 sr sec in the energy range 200 - 3,000 GeV. This result is in good agreement with those of several other groups. We discuss our data in terms of Feynman's and Koba-Nielsen-Olesen's scaling law of high energy particle production model. Interpreted in terms of an assumption of mild violation of the scaling law as x.d delta-s / delta-s indx = AE sup(2a)exp (-BE sup(a)x), our gamma ray spectrum results suggest an existence of a violation parameter of a = 0.18, which is consistent with results from gamma ray spectrum observations at great depth such as the mountain elevations. (author)

The Far-Infrared Emission Line and Continuum Spectrum of the Seyfert Galaxy NGC 1068

Science.gov (United States)

Spinoglio, Luigi; Smith, Howard A.; Gonzalez-Alfonso, Eduardo; Fisher, Jacqueline

2005-01-01

We report on the analysis of the first complete far-infrared spectrum (43-197 microns) of the Seyfert 2 galaxy NGC 1068 as observed with the Long Wavelength Spectrometer (LWS) onboard the Infrared Space Observatory (ISO). In addition to the 7 expected ionic fine structure emission lines, the OH rotational lines at 79, 119 and 163 microns were all detected in emission, which is unique among galaxies with full LWS spectra, where the 119 micron line, where detected, is always in absorption. The observed line intensities were modelled together with IS0 Short Wavelength Spectrometer (SWS) and optical and ultraviolet line intensities from the literature, considering two independent emission components: the AGN component and the starburst component in the circumnuclear ring of approximately 3kpc in size. Using the UV to mid-IR emission line spectrum to constrain the nuclear ionizing continuum, we have confirmed previous results: a canonical power-law ionizing spectrum is a poorer fit than one with a deep absorption trough, while the presence of a big blue bump is ruled out. Based on the instantaneous starburst age of 5 Myr constrained by the Br gamma equivalent width in the starburst ring, and starburst synthesis models of the mid- and far-infrared fine-structure line emission, a low ionization parameter (U=10(exp -3.5)) and low densities (n=100 cm (exp -3)) are derived. Combining the AGN and starburst components, we succeed in modeling the overall UV to far-IR atomic spectrum of SGC 1068, reproducing the line fluxes to within a factor 2.0 on average with a standard deviation of 1.4. The OH 119 micron emission indicates that the line is collisionally excited, and arises in a warm and dense region. The OH emission has been modeled using spherically symmetric, non-local, non-LTE radiative transfer models. The models indicate that the bulk of the emission arises from the nuclear region, although some extended contribution from the starburst is not ruled out. The OH abundance

Spectral Envelopes and Additive + Residual Analysis/Synthesis

Science.gov (United States)

Rodet, Xavier; Schwarz, Diemo

The subject of this chapter is the estimation, representation, modification, and use of spectral envelopes in the context of sinusoidal-additive-plus-residual analysis/synthesis. A spectral envelope is an amplitude-vs-frequency function, which may be obtained from the envelope of a short-time spectrum (Rodet et al., 1987; Schwarz, 1998). [Precise definitions of such an envelope and short-time spectrum (STS) are given in Section 2.] The additive-plus-residual analysis/synthesis method is based on a representation of signals in terms of a sum of time-varying sinusoids and of a non-sinusoidal residual signal [e.g., see Serra (1989), Laroche et al. (1993), McAulay and Quatieri (1995), and Ding and Qian (1997)]. Many musical sound signals may be described as a combination of a nearly periodic waveform and colored noise. The nearly periodic part of the signal can be viewed as a sum of sinusoidal components, called partials, with time-varying frequency and amplitude. Such sinusoidal components are easily observed on a spectral analysis display (Fig. 5.1) as obtained, for instance, from a discrete Fourier transform.

Collisional-radiative model for the visible spectrum of W{sup 26+} ions

Energy Technology Data Exchange (ETDEWEB)

Ding, Xiaobin, E-mail: dingxb@nwnu.edu.cn [Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province, College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China); Liu, Jiaxin [Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province, College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China); Koike, Fumihiro [Department of Physics, Sophia University, Tokyo, 102-8554 (Japan); Murakami, Izumi; Kato, Daiji; Sakaue, Hiroyuki A. [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan); Nakamura, Nobuyuki [Institute for Laser Science, The University of Electro-Communications, Chofu, Tokyo 182-8585 (Japan); Dong, Chenzhong [Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province, College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China)

2016-02-22

Plasma diagnostics in magnetic confinement fusion plasmas by using visible spectrum strongly depends on the knowledge of fundamental atomic properties. A detailed collisional-radiative model of W{sup 26+} ions has been constructed by considering radiative and electron excitation processes, in which the necessary atomic data had been calculated by relativistic configuration interaction method with the implementation of Flexible Atomic Code. The visible spectrum observed at an electron beam ion trap (EBIT) in Shanghai in the range of 332 nm to 392 nm was reproduced by present calculations. Some transition pairs of which the intensity ratio is sensitive to the electron density were selected as potential candidates of plasma diagnostics. Their electron density dependence is theoretically evaluated for the cases of EBIT plasmas and magnetic confinement fusion plasmas.

Easy synthesis of graphene sheets from alfalfa plants by treatment of nitric acid

International Nuclear Information System (INIS)

Qu, Jiao; Luo, Chunqiu; Zhang, Qian; Cong, Qiao; Yuan, Xing

2013-01-01

Highlights: ► An easy method for synthesis of graphene sheets using alfalfa plants was introduced. ► An novelty formation mechanism of graphene sheets using alfalfa plants was proposed. ► This method exploits a new carbon source and provides a novel idea to synthesize graphene sheets. -- Abstract: This letter focuses on synthesis of graphene sheets from alfalfa plants by treatment of nitric acid. The transmission electron microscopy image (TEM) demonstrates that the graphene sheets are agglomerated and overlapped, the energy dispersive spectrum (EDS) indicates that the products are pure, and the Raman spectrum shows the graphene sheets are well graphitized. In addition, the formation mechanism of the graphene sheets from alfalfa plants by treatment nitric acid is discussed. These findings inspire the search for a new strategy for synthesis of graphene sheets from renewable natural products, and the lower cost of this new process and carbon source may facilitate industrial production

Easy synthesis of graphene sheets from alfalfa plants by treatment of nitric acid

Energy Technology Data Exchange (ETDEWEB)

Qu, Jiao, E-mail: qujiao@bhu.edu.cn [School of Chemistry and Chemical Engineering, Bohai University, Jinzhou 121013 (China); School of Urban and Environmental Sciences, Northeast Normal University, Changchun 130024 (China); Luo, Chunqiu, E-mail: fplj_lcq@163.com [School of Chemistry and Chemical Engineering, Bohai University, Jinzhou 121013 (China); Zhang, Qian; Cong, Qiao [School of Chemistry and Chemical Engineering, Bohai University, Jinzhou 121013 (China); Yuan, Xing [School of Urban and Environmental Sciences, Northeast Normal University, Changchun 130024 (China)

2013-04-01

Highlights: ► An easy method for synthesis of graphene sheets using alfalfa plants was introduced. ► An novelty formation mechanism of graphene sheets using alfalfa plants was proposed. ► This method exploits a new carbon source and provides a novel idea to synthesize graphene sheets. -- Abstract: This letter focuses on synthesis of graphene sheets from alfalfa plants by treatment of nitric acid. The transmission electron microscopy image (TEM) demonstrates that the graphene sheets are agglomerated and overlapped, the energy dispersive spectrum (EDS) indicates that the products are pure, and the Raman spectrum shows the graphene sheets are well graphitized. In addition, the formation mechanism of the graphene sheets from alfalfa plants by treatment nitric acid is discussed. These findings inspire the search for a new strategy for synthesis of graphene sheets from renewable natural products, and the lower cost of this new process and carbon source may facilitate industrial production.

The Exponential Model for the Spectrum of a Time Series: Extensions and Applications

DEFF Research Database (Denmark)

Proietti, Tommaso; Luati, Alessandra

The exponential model for the spectrum of a time series and its fractional extensions are based on the Fourier series expansion of the logarithm of the spectral density. The coefficients of the expansion form the cepstrum of the time series. After deriving the cepstrum of important classes of time...

Ultrahigh-energy cosmic-ray spectrum

International Nuclear Information System (INIS)

Hill, C.T.; Schramm, D.N.

1985-01-01

We analyze the evolution of the ultrahigh-energy cosmic-ray spectrum upon traversing the 2.7 0 K microwave background with respect to pion photoproduction, pair-production reactions, and cosmological effects. Our approach employs exact transport equations which manifestly conserve nucleon number and embody the laboratory details of these reactions. A spectrum enhancement appears around 6 x 10 19 eV due to the ''pile-up'' of energy-degraded nucleons, and a ''dip'' occurs around 10 19 eV due to combined effects. Both of these features appear in the observational spectrum. We analyze the resulting neutrino spectrum and the effects of cosmological source distributions. We present a complete model of the ultrahigh-energy spectrum and anisotropy in reasonable agreement with observation and which predicts an observable electron-neutrino spectrum

Subtask 2.4 - Integration and Synthesis in Climate Change Predictive Modeling

Energy Technology Data Exchange (ETDEWEB)

Jaroslav Solc

2009-06-01

The Energy & Environmental Research Center (EERC) completed a brief evaluation of the existing status of predictive modeling to assess options for integration of our previous paleohydrologic reconstructions and their synthesis with current global climate scenarios. Results of our research indicate that short-term data series available from modern instrumental records are not sufficient to reconstruct past hydrologic events or predict future ones. On the contrary, reconstruction of paleoclimate phenomena provided credible information on past climate cycles and confirmed their integration in the context of regional climate history is possible. Similarly to ice cores and other paleo proxies, acquired data represent an objective, credible tool for model calibration and validation of currently observed trends. It remains a subject of future research whether further refinement of our results and synthesis with regional and global climate observations could contribute to improvement and credibility of climate predictions on a regional and global scale.

Video Modeling for Children and Adolescents with Autism Spectrum Disorder: A Meta-Analysis

Science.gov (United States)

Thompson, Teresa Lynn

2014-01-01

The objective of this research was to conduct a meta-analysis to examine existing research studies on video modeling as an effective teaching tool for children and adolescents diagnosed with Autism Spectrum Disorder (ASD). Study eligibility criteria included (a) single case research design using multiple baselines, alternating treatment designs,…

Learning strategies: a synthesis and conceptual model

Science.gov (United States)

Hattie, John A. C.; Donoghue, Gregory M.

2016-08-01

The purpose of this article is to explore a model of learning that proposes that various learning strategies are powerful at certain stages in the learning cycle. The model describes three inputs and outcomes (skill, will and thrill), success criteria, three phases of learning (surface, deep and transfer) and an acquiring and consolidation phase within each of the surface and deep phases. A synthesis of 228 meta-analyses led to the identification of the most effective strategies. The results indicate that there is a subset of strategies that are effective, but this effectiveness depends on the phase of the model in which they are implemented. Further, it is best not to run separate sessions on learning strategies but to embed the various strategies within the content of the subject, to be clearer about developing both surface and deep learning, and promoting their associated optimal strategies and to teach the skills of transfer of learning. The article concludes with a discussion of questions raised by the model that need further research.

MATHEMATICAL AND COMPUTATIONAL MODELLING OF RIBOSOMAL MOVEMENT AND PROTEIN SYNTHESIS: AN OVERVIEW

Directory of Open Access Journals (Sweden)

Tobias von der Haar

2012-04-01

Full Text Available Translation or protein synthesis consists of a complex system of chemical reactions, which ultimately result in decoding of the mRNA and the production of a protein. The complexity of this reaction system makes it difficult to quantitatively connect its input parameters (such as translation factor or ribosome concentrations, codon composition of the mRNA, or energy availability to output parameters (such as protein synthesis rates or ribosome densities on mRNAs. Mathematical and computational models of translation have now been used for nearly five decades to investigate translation, and to shed light on the relationship between the different reactions in the system. This review gives an overview over the principal approaches used in the modelling efforts, and summarises some of the major findings that were made.

Genetic and non-genetic animal models for autism spectrum disorders (ASD).

Science.gov (United States)

Ergaz, Zivanit; Weinstein-Fudim, Liza; Ornoy, Asher

2016-09-01

Autism spectrum disorder (ASD) is associated, in addition to complex genetic factors, with a variety of prenatal, perinatal and postnatal etiologies. We discuss the known animal models, mostly in mice and rats, of ASD that helps us to understand the etiology, pathogenesis and treatment of human ASD. We describe only models where behavioral testing has shown autistic like behaviors. Some genetic models mimic known human syndromes like fragile X where ASD is part of the clinical picture, and others are without defined human syndromes. Among the environmentally induced ASD models in rodents, the most common model is the one induced by valproic acid (VPA) either prenatally or early postnatally. VPA induces autism-like behaviors following single exposure during different phases of brain development, implying that the mechanism of action is via a general biological mechanism like epigenetic changes. Maternal infection and inflammation are also associated with ASD in man and animal models. Copyright © 2016 Elsevier Inc. All rights reserved.

PROGRESS TOWARDS MODELING OF FISCHER TROPSCH SYNTHESIS IN A SLURRY BUBBLE COLUMN REACTOR

Energy Technology Data Exchange (ETDEWEB)

Donna Post Guillen; Tami Grimmett; Anastasia M. Gandrik; Steven P. Antal

2010-11-01

The Hybrid Energy Systems Testing (HYTEST) Laboratory is being established at the Idaho National Laboratory to develop and test hybrid energy systems with the principal objective to safeguard U.S. Energy Security by reducing dependence on foreign petroleum. A central component of the HYTEST is the slurry bubble column reactor (SBCR) in which the gas-to-liquid reactions will be performed to synthesize transportation fuels using the Fischer Tropsch (FT) process. SBCRs are cylindrical vessels in which gaseous reactants (for example, synthesis gas or syngas) is sparged into a slurry of liquid reaction products and finely dispersed catalyst particles. The catalyst particles are suspended in the slurry by the rising gas bubbles and serve to promote the chemical reaction that converts syngas to a spectrum of longer chain hydrocarbon products, which can be upgraded to gasoline, diesel or jet fuel. These SBCRs operate in the churn-turbulent flow regime which is characterized by complex hydrodynamics, coupled with reacting flow chemistry and heat transfer, that effect reactor performance. The purpose of this work is to develop a computational multiphase fluid dynamic (CMFD) model to aid in understanding the physico-chemical processes occurring in the SBCR. Our team is developing a robust methodology to couple reaction kinetics and mass transfer into a four-field model (consisting of the bulk liquid, small bubbles, large bubbles and solid catalyst particles) that includes twelve species: (1) CO reactant, (2) H2 reactant, (3) hydrocarbon product, and (4) H2O product in small bubbles, large bubbles, and the bulk fluid. Properties of the hydrocarbon product were specified by vapor liquid equilibrium calculations. The absorption and kinetic models, specifically changes in species concentrations, have been incorporated into the mass continuity equation. The reaction rate is determined based on the macrokinetic model for a cobalt catalyst developed by Yates and Satterfield [1]. The

The Coyote Universe II: Cosmological Models and Precision Emulation of the Nonlinear Matter Power Spectrum

Energy Technology Data Exchange (ETDEWEB)

Heitmann, Katrin [Los Alamos National Laboratory; Habib, Salman [Los Alamos National Laboratory; Higdon, David [Los Alamos National Laboratory; Williams, Brian J [Los Alamos National Laboratory; White, Martin [Los Alamos National Laboratory; Wagner, Christian [Los Alamos National Laboratory

2008-01-01

The power spectrum of density fluctuations is a foundational source of cosmological information. Precision cosmological probes targeted primarily at investigations of dark energy require accurate theoretical determinations of the power spectrum in the nonlinear regime. To exploit the observational power of future cosmological surveys, accuracy demands on the theory are at the one percent level or better. Numerical simulations are currently the only way to produce sufficiently error-controlled predictions for the power spectrum. The very high computational cost of (precision) N-body simulations is a major obstacle to obtaining predictions in the nonlinear regime, while scanning over cosmological parameters. Near-future observations, however, are likely to provide a meaningful constraint only on constant dark energy equation of state 'wCDM' cosmologies. In this paper we demonstrate that a limited set of only 37 cosmological models -- the 'Coyote Universe' suite -- can be used to predict the nonlinear matter power spectrum at the required accuracy over a prior parameter range set by cosmic microwave background observations. This paper is the second in a series of three, with the final aim to provide a high-accuracy prediction scheme for the nonlinear matter power spectrum for wCDM cosmologies.

High-resolution observations of low-luminosity gigahertz-peaked spectrum and compact steep-spectrum sources

Science.gov (United States)

Collier, J. D.; Tingay, S. J.; Callingham, J. R.; Norris, R. P.; Filipović, M. D.; Galvin, T. J.; Huynh, M. T.; Intema, H. T.; Marvil, J.; O'Brien, A. N.; Roper, Q.; Sirothia, S.; Tothill, N. F. H.; Bell, M. E.; For, B.-Q.; Gaensler, B. M.; Hancock, P. J.; Hindson, L.; Hurley-Walker, N.; Johnston-Hollitt, M.; Kapińska, A. D.; Lenc, E.; Morgan, J.; Procopio, P.; Staveley-Smith, L.; Wayth, R. B.; Wu, C.; Zheng, Q.; Heywood, I.; Popping, A.

2018-06-01

We present very long baseline interferometry observations of a faint and low-luminosity (L1.4 GHz GPS) and compact steep-spectrum (CSS) sample. We select eight sources from deep radio observations that have radio spectra characteristic of a GPS or CSS source and an angular size of θ ≲ 2 arcsec, and detect six of them with the Australian Long Baseline Array. We determine their linear sizes, and model their radio spectra using synchrotron self-absorption (SSA) and free-free absorption (FFA) models. We derive statistical model ages, based on a fitted scaling relation, and spectral ages, based on the radio spectrum, which are generally consistent with the hypothesis that GPS and CSS sources are young and evolving. We resolve the morphology of one CSS source with a radio luminosity of 10^{25} W Hz^{-1}, and find what appear to be two hotspots spanning 1.7 kpc. We find that our sources follow the turnover-linear size relation, and that both homogeneous SSA and an inhomogeneous FFA model can account for the spectra with observable turnovers. All but one of the FFA models do not require a spectral break to account for the radio spectrum, while all but one of the alternative SSA and power-law models do require a spectral break to account for the radio spectrum. We conclude that our low-luminosity sample is similar to brighter samples in terms of their spectral shape, turnover frequencies, linear sizes, and ages, but cannot test for a difference in morphology.

Modelling, Synthesis, and Configuration of Networks-on-Chips

DEFF Research Database (Denmark)

Stuart, Matthias Bo

This thesis presents three contributions in two different areas of network-on-chip and system-on-chip research: Application modelling and identifying and solving different optimization problems related to two specific network-on-chip architectures. The contribution related to application modelling...... is an analytical method for deriving the worst-case traffic pattern caused by an application and the cache-coherence protocol in a cache-coherent shared-memory system. The contributions related to network-on-chip optimization problems consist of two parts: The development and evaluation of six heuristics...... for solving the network synthesis problem in the MANGO network-on-chip, and the identification and formalization of the ReNoC configuration problem together with three heuristics for solving it....

Examination of models of knee in primary cosmic ray spectrum using gamma-hadron families

International Nuclear Information System (INIS)

Sveshnikova, L.G.; Managadze, A.K.; Roganova, T.M.; Mukhamedshin, R.A.

2005-01-01

Four models for describing the primary cosmic radiation (PCR) spectrum are proposed/ The examination of the PCR spectra models is carried out from the viewpoint of their consistency with the data on the gamma-hadron families for the threshold energies of 100 and 500 TeV. The maximum possible contribution of the superfamilies, originating from the primary nuclei, but not from the protons, is calculated [ru

The Development and Course of Bipolar Spectrum Disorders: An Integrated Reward and Circadian Rhythm Dysregulation Model

Science.gov (United States)

Alloy, Lauren B.; Nusslock, Robin; Boland, Elaine M.

2014-01-01

In this article, we present and review the evidence for two major biopsychosocial theories of the onset and course of bipolar spectrum disorders (BSDs) that integrate behavioral, environmental, and neurobiological mechanisms: the reward hypersensitivity and the social and circadian rhythm disruption models. We describe the clinical features, spectrum, age of onset, and course of BSDs. We then discuss research designs relevant to demonstrating whether a hypothesized mechanism represents a correlate, vulnerability, or predictor of the course of BSDs, as well as important methodological issues. We next present the reward hypersensitivity model of BSD, followed by the social/circadian rhythm disruption model of BSD. For each model, we review evidence regarding whether the proposed underlying mechanism is associated with BSDs, provides vulnerability to the onset of BSDs, and predicts the course of BSDs. We then present a new integrated reward/circadian rhythm (RCR) dysregulation model of BSD and discuss how the RCR model explains the symptoms, onset, and course of BSDs. We end with recommendations for future research directions. PMID:25581235

Self-similar formation of the Kolmogorov spectrum in the Leith model of turbulence

International Nuclear Information System (INIS)

Nazarenko, S V; Grebenev, V N

2017-01-01

The last stage of evolution toward the stationary Kolmogorov spectrum of hydrodynamic turbulence is studied using the Leith model [1]. This evolution is shown to manifest itself as a reflection wave in the wavenumber space propagating from the largest toward the smallest wavenumbers, and is described by a self-similar solution of a new (third) kind. This stage follows the previously studied stage of an initial explosive propagation of the spectral front from the smallest to the largest wavenumbers reaching arbitrarily large wavenumbers in a finite time, and which was described by a self-similar solution of the second kind [2–4]. Nonstationary solutions corresponding to ‘warm cascades’ characterised by a thermalised spectrum at large wavenumbers are also obtained. (paper)

Physics Implications of Flat Directions in Free Fermionic Superstring Models; 1, Mass Spectrum and Couplings

CERN Document Server

Cleaver, G; Espinosa, J R; Everett, L; Langacker, P G; Wang, J

1999-01-01

From the "top-down" approach we investigate physics implications of the class of D- and F- flat directions formed from non-Abelian singlets which are proven flat to all orders in the nonrenormalizable superpotential, for a prototype quasi-realistic free fermionic string model with the standard model gauge group and three families (CHL5). These flat directions have at least an additional U(1)' unbroken at the string scale. For each flat direction, the complete set of effective mass terms and effective trilinear superpotential terms in the observable sector are computed to all orders in the VEV's of the fields in the flat direction. The "string selection-rules" disallow a large number of couplings allowed by gauge invariance, resulting in a massless spectrum with a large number of exotics, in most cases excluded by experiment, thus signifying a generic flaw of these models. Nevertheless, the resulting trilinear couplings of the massless spectrum possess a number of interesting features which we analyse for two ...

Power to Fuels: Dynamic Modeling of a Slurry Bubble Column Reactor in Lab-Scale for Fischer Tropsch Synthesis under Variable Load of Synthesis Gas

Directory of Open Access Journals (Sweden)

Siavash Seyednejadian

2018-03-01

Full Text Available This research developed a comprehensive computer model for a lab-scale Slurry Bubble Column Reactor (SBCR (0.1 m Dt and 2.5 m height for Fischer–Tropsch (FT synthesis under flexible operation of synthesis gas load flow rates. The variable loads of synthesis gas are set at 3.5, 5, 7.5 m3/h based on laboratory adjustments at three different operating temperatures (483, 493 and 503 K. A set of Partial Differential Equations (PDEs in the form of mass transfer and chemical reaction are successfully coupled to predict the behavior of all the FT components in two phases (gas and liquid over the reactor bed. In the gas phase, a single-bubble-class-diameter (SBCD is adopted and the reduction of superficial gas velocity through the reactor length is incorporated into the model by the overall mass balance. Anderson Schulz Flory distribution is employed for reaction kinetics. The modeling results are in good agreement with experimental data. The results of dynamic modeling show that the steady state condition is attained within 10 min from start-up. Furthermore, they show that step-wise syngas flow rate does not have a detrimental influence on FT product selectivity and the dynamic modeling of the slurry reactor responds quite well to the load change conditions.

Synthesis, microwave spectrum, and dipole moment of allenylisocyanide (H2C═C═CHNC), a compound of potential astrochemical interest.

Science.gov (United States)

Møllendal, Harald; Samdal, Svein; Matrane, Abdellatif; Guillemin, Jean-Claude

2011-07-14

An improved synthesis of a compound of potential astrochemical interest, allenylisocyanide (H(2)C═C═CHNC), is reported together with its microwave spectrum, which has been investigated in the 8-120 GHz spectral range to facilitate a potential identification in interstellar space. The spectra of the ground vibrational state and of five vibrationally excited states belonging to three different vibrational modes have been assigned for the parent species. A total of 658 transitions with a maximum value of J = 71 were assigned for the ground state and accurate values obtained for the rotational and quartic centrifugal distortion constants. The spectra of five heavy-atom ((13)C and (15)N) isotopologues were also assigned. The dipole moment was determined to be μ(a) = 11.93(16) × 10(-30) C m, μ(b) = 4.393(44) × 10(-30) C m, and μ(tot) = 12.71(16) × 10(-30) C m. The spectroscopic work has been augmented by theoretical calculations at the CCSD/cc-pVTZ and B3LYP/cc-pVTZ levels of theory. The theoretical calculations are generally in good agreement with the experimental results.

GALEV evolutionary synthesis models – I. Code, input physics and web

NARCIS (Netherlands)

Kotulla, R.; Fritze, U.; Weilbacher, P.; Anders, P.

2009-01-01

GALEV (GALaxy EVolution) evolutionary synthesis models describe the evolution of stellar populations in general, of star clusters as well as of galaxies, both in terms of resolved stellar populations and of integrated light properties over cosmological time-scales of ≥13 Gyr from the onset of star

An evidence synthesis of the international knowledge base for new care models to inform and mobilise knowledge for multispecialty community providers (MCPs).

Science.gov (United States)

Turner, Alison; Mulla, Abeda; Booth, Andrew; Aldridge, Shiona; Stevens, Sharon; Battye, Fraser; Spilsbury, Peter

2016-10-01

NHS England's Five Year Forward View (NHS England, Five Year Forward View, 2014) formally introduced a strategy for new models of care driven by simultaneous pressures to contain costs, improve care and deliver services closer to home through integrated models. This synthesis focuses on a multispecialty community provider (MCP) model. This new model of care seeks to overcome the limitations in current models of care, often based around single condition-focused pathways, in contrast to patient-focused delivery (Royal College of General Practitioners, The 2022 GP: compendium of evidence, 2012) which offers greater continuity of care in recognition of complex needs and multimorbidity. The synthesis, an innovative combination of best fit framework synthesis and realist synthesis, will develop a "blueprint" which articulates how and why MCP models work, to inform design of future iterations of the MCP model. A systematic search will be conducted to identify research and practice-derived evidence to achieve a balance that captures the historical legacy of MCP models but focuses on contemporary evidence. Sources will include bibliographic databases including MEDLINE, PreMEDLINE, CINAHL, Embase, HMIC and Cochrane Library; and grey literature sources. The Best Fit synthesis methodology will be combined with a synthesis following realist principles which are particularly suited to exploring what works, when, for whom and in what circumstances. The aim of this synthesis is to provide decision makers in health and social care with a practical evidence base relating to the multispecialty community provider (MCP) model of care. PROSPERO CRD42016039552 .

Discovery of Antibiotics-derived Polymers for Gene Delivery using Combinatorial Synthesis and Cheminformatics Modeling

Science.gov (United States)

Potta, Thrimoorthy; Zhen, Zhuo; Grandhi, Taraka Sai Pavan; Christensen, Matthew D.; Ramos, James; Breneman, Curt M.; Rege, Kaushal

2014-01-01

We describe the combinatorial synthesis and cheminformatics modeling of aminoglycoside antibiotics-derived polymers for transgene delivery and expression. Fifty-six polymers were synthesized by polymerizing aminoglycosides with diglycidyl ether cross-linkers. Parallel screening resulted in identification of several lead polymers that resulted in high transgene expression levels in cells. The role of polymer physicochemical properties in determining efficacy of transgene expression was investigated using Quantitative Structure-Activity Relationship (QSAR) cheminformatics models based on Support Vector Regression (SVR) and ‘building block’ polymer structures. The QSAR model exhibited high predictive ability, and investigation of descriptors in the model, using molecular visualization and correlation plots, indicated that physicochemical attributes related to both, aminoglycosides and diglycidyl ethers facilitated transgene expression. This work synergistically combines combinatorial synthesis and parallel screening with cheminformatics-based QSAR models for discovery and physicochemical elucidation of effective antibiotics-derived polymers for transgene delivery in medicine and biotechnology. PMID:24331709

Video Modeling and Children with Autism Spectrum Disorder: A Survey of Caregiver Perspectives

Science.gov (United States)

Cardon, Teresa A.; Guimond, Amy; Smith-Treadwell, Amanda M.

2015-01-01

Video modeling (VM) has shown promise as an effective intervention for individuals with autism spectrum disorder (ASD); however, little is known about what may promote or prevent caregivers' use of this intervention. While VM is an effective tool to support skill development among a wide range of children in research and clinical settings, VM is…

Brief Report: Whole Blood Serotonin Levels and Gastrointestinal Symptoms in Autism Spectrum Disorder

Science.gov (United States)

Marler, Sarah; Ferguson, Bradley J.; Lee, Evon Batey; Peters, Brittany; Williams, Kent C.; McDonnell, Erin; Macklin, Eric A.; Levitt, Pat; Gillespie, Catherine Hagan; Anderson, George M.; Margolis, Kara Gross; Beversdorf, David Q.; Veenstra-VanderWeele, Jeremy

2016-01-01

Elevated whole blood serotonin levels are observed in more than 25% of children with autism spectrum disorder (ASD). Co-occurring gastrointestinal (GI) symptoms are also common in ASD but have not previously been examined in relationship with hyperserotonemia, despite the synthesis of serotonin in the gut. In 82 children and adolescents with ASD,…

A Dynamic Spectrum Allocation Algorithm for a Maritime Cognitive Radio Communication System Based on a Queuing Model

Directory of Open Access Journals (Sweden)

Jingbo Zhang

2017-09-01

Full Text Available With the rapid development of maritime digital communication, the demand for spectrum resources is increasing, and building a maritime cognitive radio communication system is an effective solution. In this paper, the problem of how to effectively allocate the spectrum for secondary users (SUs with different priorities in a maritime cognitive radio communication system is studied. According to the characteristics of a maritime cognitive radio and existing research about cognitive radio systems, this paper establishes a centralized maritime cognitive radio communication model and creates a simplified queuing model with two queues for the communication model. In the view of the behaviors of SUs and primary users (PUs, we propose a dynamic spectrum allocation (DSA algorithm based on the system status, and analyze it with a two-dimensional Markov chain. Simulation results show that, when different types of SUs have similar arrival rates, the algorithm can vary the priority factor according to the change of users’ status in the system, so as to adjust the channel allocation, decreasing system congestion. The improvement of the algorithm is about 7–26%, and the specific improvement is negatively correlated with the SU arrival rate.

Change detection in the dynamics of an intracellular protein synthesis model using nonlinear Kalman filtering.

Science.gov (United States)

Rigatos, Gerasimos G; Rigatou, Efthymia G; Djida, Jean Daniel

2015-10-01

A method for early diagnosis of parametric changes in intracellular protein synthesis models (e.g. the p53 protein - mdm2 inhibitor model) is developed with the use of a nonlinear Kalman Filtering approach (Derivative-free nonlinear Kalman Filter) and of statistical change detection methods. The intracellular protein synthesis dynamic model is described by a set of coupled nonlinear differential equations. It is shown that such a dynamical system satisfies differential flatness properties and this allows to transform it, through a change of variables (diffeomorphism), to the so-called linear canonical form. For the linearized equivalent of the dynamical system, state estimation can be performed using the Kalman Filter recursion. Moreover, by applying an inverse transformation based on the previous diffeomorphism it becomes also possible to obtain estimates of the state variables of the initial nonlinear model. By comparing the output of the Kalman Filter (which is assumed to correspond to the undistorted dynamical model) with measurements obtained from the monitored protein synthesis system, a sequence of differences (residuals) is obtained. The statistical processing of the residuals with the use of x2 change detection tests, can provide indication within specific confidence intervals about parametric changes in the considered biological system and consequently indications about the appearance of specific diseases (e.g. malignancies).

Probing evolutionary population synthesis models in the near infrared with early-type galaxies

Science.gov (United States)

Dahmer-Hahn, Luis Gabriel; Riffel, Rogério; Rodríguez-Ardila, Alberto; Martins, Lucimara P.; Kehrig, Carolina; Heckman, Timothy M.; Pastoriza, Miriani G.; Dametto, Natacha Z.

2018-06-01

We performed a near-infrared (NIR; ˜1.0 -2.4 μm) stellar population study in a sample of early-type galaxies. The synthesis was performed using five different evolutionary population synthesis libraries of models. Our main results can be summarized as follows: low-spectral-resolution libraries are not able to produce reliable results when applied to the NIR alone, with each library finding a different dominant population. The two newest higher resolution models, on the other hand, perform considerably better, finding consistent results to each other and to literature values. We also found that optical results are consistent with each other even for lower resolution models. We also compared optical and NIR results and found out that lower resolution models tend to disagree in the optical and in the NIR, with higher fraction of young populations in the NIR and dust extinction ˜1 mag higher than optical values. For higher resolution models, optical and NIR results tend to agree much better, suggesting that a higher spectral resolution is fundamental to improve the quality of the results.

Model for the mechanism and regulation of chitosan synthesis in Mucor rouxii

International Nuclear Information System (INIS)

Davis, L.L.; Bartnicki-Garcia, S.

1984-01-01

The cell walls of mucoraceous fungi are characterized by the joint occurrence of chitosan and chitin, the β-1,4-linked polysaccharides of G1cN and G1cNAc, respectively. It has been proposed that chitosan is made from chitin by enzymatic deacetylation, but the evidence is inconclusive since the deacetylase isolated from Mucor rouxii is effective against glycol chitin, but not against genuine chitin; consequently, chitosan synthesis in vitro was not achieved. The authors discovered that the same deacetylase can deacetylate chitin efficiently if it is allowed to act on chitin chains as they are being formed; i.e. the simultaneous presence and operation of chitin synthetase and chitin deacetylase is required for chitosan synthesis. Subsequent studies on the effect of digitonin on chitosan synthesis were the basis for a model the authors have developed for the regulation of chitosan and chitin syntheses in vivo

Adaptive Texture Synthesis for Large Scale City Modeling

Science.gov (United States)

Despine, G.; Colleu, T.

2015-02-01

Large scale city models textured with aerial images are well suited for bird-eye navigation but generally the image resolution does not allow pedestrian navigation. One solution to face this problem is to use high resolution terrestrial photos but it requires huge amount of manual work to remove occlusions. Another solution is to synthesize generic textures with a set of procedural rules and elementary patterns like bricks, roof tiles, doors and windows. This solution may give realistic textures but with no correlation to the ground truth. Instead of using pure procedural modelling we present a method to extract information from aerial images and adapt the texture synthesis to each building. We describe a workflow allowing the user to drive the information extraction and to select the appropriate texture patterns. We also emphasize the importance to organize the knowledge about elementary pattern in a texture catalogue allowing attaching physical information, semantic attributes and to execute selection requests. Roofs are processed according to the detected building material. Façades are first described in terms of principal colours, then opening positions are detected and some window features are computed. These features allow selecting the most appropriate patterns from the texture catalogue. We experimented this workflow on two samples with 20 cm and 5 cm resolution images. The roof texture synthesis and opening detection were successfully conducted on hundreds of buildings. The window characterization is still sensitive to the distortions inherent to the projection of aerial images onto the facades.

Markov modeling and reliability analysis of urea synthesis system of a fertilizer plant

Science.gov (United States)

Aggarwal, Anil Kr.; Kumar, Sanjeev; Singh, Vikram; Garg, Tarun Kr.

2015-12-01

This paper deals with the Markov modeling and reliability analysis of urea synthesis system of a fertilizer plant. This system was modeled using Markov birth-death process with the assumption that the failure and repair rates of each subsystem follow exponential distribution. The first-order Chapman-Kolmogorov differential equations are developed with the use of mnemonic rule and these equations are solved with Runga-Kutta fourth-order method. The long-run availability, reliability and mean time between failures are computed for various choices of failure and repair rates of subsystems of the system. The findings of the paper are discussed with the plant personnel to adopt and practice suitable maintenance policies/strategies to enhance the performance of the urea synthesis system of the fertilizer plant.

3D-modelling of bifunctional core-shell catalysts for the production of fuels from biomass-based synthesis gas

Energy Technology Data Exchange (ETDEWEB)

Ding, Wenjin; Lee, Seung Cheol; Li, Hui; Pfeifer, Peter; Dittmeyer, Roland [Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen (Germany). Inst. for Micro Process Engineering (IMVT)

2013-09-01

Until now, the main route for the production of DME from synthesis gas in industry is methanol synthesis on a metallic catalyst and subsequent dehydration of methanol on an acid catalyst (two-step process). A single-step process using bifunctional catalysts to perform the two steps simultaneously would be preferred e.g. due to thermodynamic considerations; but this is impeded by the higher volumetric heat release which may cause deactivation of the methanol synthesis catalyst function. Thus we propose to conduct the reaction in a microchannel reactor. However, in order to increase the productivity of the microchannel reactor and to lower the investment costs, we aim at a high selectivity and activity of the catalyst. The continuously removal of methanol by dehydration on an acidic ZSM-5 catalyst as shell improves the thermodynamic conditions of methanol synthesis in the CuO/ZnO/Al{sub 2}O{sub 3} core; thus, the synthesis gas conversion can be higher than that determined by the thermodynamics of pure methanol synthesis. The molecular sieving in the zeolite layer can further lead to higher selectivity of DME at milder reaction conditions. However, mass transport limitation of the synthesis gas to the catalyst core should not hinder the reaction, and therefore a more detailed investigation is required. In order to computer-aided optimize the catalyst structure and the operating conditions for core-shell catalysts, a simulation model should be developed to study the coupled reaction and transport processes in core-shell catalysts. In this simulation model the complicated interaction of diffusion and reaction in the zeolite layer (shell) must be detailed by a network model to describe its structure and the mechanisms effectively. In addition, suitable diffusion and kinetic models are required to describe the mass transport and reactions in the layer. Suitable networks, diffusion and kinetic models are discussed for 3D simulations in this contribution. (orig.)

GH dysfunction in Engrailed-2 knockout mice, a model for autism spectrum disorders

Directory of Open Access Journals (Sweden)

Giovanni eProvenzano

2014-09-01

Full Text Available Insulin-like growth factor 1 (IGF-1 signaling promotes brain development and plasticity. Altered IGF-1 expression has been associated to autism spectrum disorders (ASD. IGF-1 levels were found increased in the blood and decreased in the cerebrospinal fluid of ASD children. Accordingly, IGF-1 treatment can rescue behavioral deficits in mouse models of ASD, and IGF-1 trials have been proposed for ASD children. IGF-1 is mainly synthesized in the liver, and its synthesis is dependent on growth hormone (GH produced in the pituitary gland. GH also modulates cognitive functions, and altered levels of GH have been detected in ASD patients.Here we analyzed the expression of GH, IGF-1, their receptors and regulatory hormones in the neuroendocrine system of adult male mice lacking the homeobox transcription factor Engrailed-2 (En2-/- mice. En2-/- mice display ASD-like behaviors (social interactions, defective spatial learning, increased seizure susceptibility accompanied by relevant neuropathological changes (loss of cerebellar and forebrain inhibitory neurons. Recent studies showed that En2 modulates IGF-1 activity during postnatal cerebellar development.We found that GH mRNA expression was markedly deregulated throughout the neuroendocrine axis in En2-/- mice, as compared to wild-type (WT controls. In mutant mice, GH mRNA levels were significantly increased in the pituitary gland, blood and liver, whereas decreased levels were detected in the hippocampus. These changes were paralleled by decreased levels of GH protein in the hippocampus but not other tissues of En2-/- mice. IGF-1 mRNA was significantly up-regulated in the liver and down-regulated in the En2-/- hippocampus, but no differences were detected in the levels of IGF-1 protein between the two genotypes. Our data strengthen the notion that altered GH levels in the hippocampus may be involved in learning disabilities associated to ASD.

Microwave Remote Sensing Modeling of Ocean Surface Salinity and Winds Using an Empirical Sea Surface Spectrum

Science.gov (United States)

Yueh, Simon H.

2004-01-01

Active and passive microwave remote sensing techniques have been investigated for the remote sensing of ocean surface wind and salinity. We revised an ocean surface spectrum using the CMOD-5 geophysical model function (GMF) for the European Remote Sensing (ERS) C-band scatterometer and the Ku-band GMF for the NASA SeaWinds scatterometer. The predictions of microwave brightness temperatures from this model agree well with satellite, aircraft and tower-based microwave radiometer data. This suggests that the impact of surface roughness on microwave brightness temperatures and radar scattering coefficients of sea surfaces can be consistently characterized by a roughness spectrum, providing physical basis for using combined active and passive remote sensing techniques for ocean surface wind and salinity remote sensing.

Formation of the Actor's/Speaker's Formant: A Study Applying Spectrum Analysis and Computer Modeling

Czech Academy of Sciences Publication Activity Database

Leino, T.; Laukkanen, A. M.; Radolf, Vojtěch

2011-01-01

Roč. 25, č. 2 (2011), s. 150-158 ISSN 0892-1997 R&D Projects: GA ČR GA101/08/1155 Institutional research plan: CEZ:AV0Z20760514 Keywords : vocal exercising * voice quality * spectrum analysis * mathematical modeling Subject RIV: BI - Acoustics Impact factor: 1.390, year: 2011

ABOUT PROBABILITY OF RESEARCH OF THE NN Ser SPECTRUM BY MODEL ATMOSPHERES METHOD

OpenAIRE

Sakhibullin, N. A.; Shimansky, V. V.

2017-01-01

The spectrum of close binary system NN Ser is investigated by a models atmospheres method. It is show that the atmosphere near the centrum of a hot spot on surface of red dwarf has powerful chromospheres, arising from heating in Laiman continua. Four models of binary system with various of parameters are constructed and their theoretical spectra are obtained. Temperature of white dwarf Tef = 62000 K, radius of the red dwarf RT = 0.20139 and angle inclination of system i = 82“ are determined. ...

Procedures and compliance of a video modeling applied behavior analysis intervention for Brazilian parents of children with autism spectrum disorders.

Science.gov (United States)

Bagaiolo, Leila F; Mari, Jair de J; Bordini, Daniela; Ribeiro, Tatiane C; Martone, Maria Carolina C; Caetano, Sheila C; Brunoni, Decio; Brentani, Helena; Paula, Cristiane S

2017-07-01

Video modeling using applied behavior analysis techniques is one of the most promising and cost-effective ways to improve social skills for parents with autism spectrum disorder children. The main objectives were: (1) To elaborate/describe videos to improve eye contact and joint attention, and to decrease disruptive behaviors of autism spectrum disorder children, (2) to describe a low-cost parental training intervention, and (3) to assess participant's compliance. This is a descriptive study of a clinical trial for autism spectrum disorder children. The parental training intervention was delivered over 22 weeks based on video modeling. Parents with at least 8 years of schooling with an autism spectrum disorder child between 3 and 6 years old with an IQ lower than 70 were invited to participate. A total of 67 parents fulfilled the study criteria and were randomized into two groups: 34 as the intervention and 33 as controls. In all, 14 videos were recorded covering management of disruptive behaviors, prompting hierarchy, preference assessment, and acquisition of better eye contact and joint attention. Compliance varied as follows: good 32.4%, reasonable 38.2%, low 5.9%, and 23.5% with no compliance. Video modeling parental training seems a promising, feasible, and low-cost way to deliver care for children with autism spectrum disorder, particularly for populations with scarce treatment resources.

Sound Synthesis of Objects Swinging through Air Using Physical Models

Directory of Open Access Journals (Sweden)

Rod Selfridge

2017-11-01

Full Text Available A real-time physically-derived sound synthesis model is presented that replicates the sounds generated as an object swings through the air. Equations obtained from fluid dynamics are used to determine the sounds generated while exposing practical parameters for a user or game engine to vary. Listening tests reveal that for the majority of objects modelled, participants rated the sounds from our model as plausible as actual recordings. The sword sound effect performed worse than others, and it is speculated that one cause may be linked to the difference between expectations of a sound and the actual sound for a given object.

Full spectrum of the two-photon and the two-mode quantum Rabi models

International Nuclear Information System (INIS)

Dossa, Anselme F.; Avossevou, Gabriel Y. H.

2014-01-01

This paper is concerned with the rigorous analytical determination of the spectrum of the two-photon and the two-mode quantum Rabi models. To reach this goal, we exploit the hidden symmetries in these models by means of the unitary and similarity transformations in addition to the Bargmann-Fock space description. In each case, the purely quantum mechanical problem of the Rabi model studied is reduced to solutions for differential equations. This eventually gives a third-order differential equation for each of these models, which is reduced to a second-order differential equation by additional transformations. The analytical expressions of the wave functions describing the energy levels are obtained in terms of the confluent hypergeometric functions

Novel Thiazole Derivatives of Medicinal Potential: Synthesis and Modeling

Directory of Open Access Journals (Sweden)

Nour E. A. Abdel-Sattar

2017-01-01

Full Text Available This paper reports on the synthesis of new thiazole derivatives that could be profitably exploited in medical treatment of tumors. Molecular electronic structures have been modeled within density function theory (DFT framework. Reactivity indices obtained from the frontier orbital energies as well as electrostatic potential energy maps are discussed and correlated with the molecular structure. X-ray crystallographic data of one of the new compounds is measured and used to support and verify the theoretical results.

Analysis and synthesis for interval type-2 fuzzy-model-based systems

CERN Document Server

Li, Hongyi; Lam, Hak-Keung; Gao, Yabin

2016-01-01

This book develops a set of reference methods capable of modeling uncertainties existing in membership functions, and analyzing and synthesizing the interval type-2 fuzzy systems with desired performances. It also provides numerous simulation results for various examples, which fill certain gaps in this area of research and may serve as benchmark solutions for the readers. Interval type-2 T-S fuzzy models provide a convenient and flexible method for analysis and synthesis of complex nonlinear systems with uncertainties.

Spectrum decision in cognitive radio networks: a survey

CSIR Research Space (South Africa)

Masonta, MT

2012-11-01

Full Text Available provides an up-to-date survey of spectrum decision in CR networks (CRNs) and addresses issues of spectrum characterization (including PU activity modelling), spectrum selection and CR reconfiguration. For each of these issues, we highlight key open research...

Direct dimethyl-ether (DME) synthesis by spatial patterned catalyst arrangement. A modeling and simulation study

Energy Technology Data Exchange (ETDEWEB)

McBride, K.; Turek, T.; Guettel, R. [Clausthal Univ. of Technology (Germany). Inst. of Chemical Process Engineering

2011-07-01

The effect of spatially patterned catalyst beds was investigated for direct DME synthesis from synthesis gas as an example. A layered arrangement of methanol synthesis and dehydration catalyst was chosen and studied by numerical simulation under typical operating conditions for single-step DME synthesis. It was revealed that catalyst layers significantly influence the DME productivity. With an increasing number of layers from 2 to 40, an increase in DME productivity was observed approaching the performance of a physical catalyst mixture for an infinite number of layers. The results prove that a physical mixture of methanol synthesis and dehydration catalyst achieves the highest DME productivity under operating conditions chosen in this study. This can be explained by the higher average methanol concentration for the layered catalyst arrangement and thus stronger equilibrium constraints for the methanol synthesis reaction. Essentially, the layered catalyst arrangement is comparable to a cascade model of the two-step process, which is less efficient in terms of DME yield than the single-step process. However, since a significant effect was found, the layered catalyst arrangement could be beneficial for other reaction systems. (orig.)

Math Interventions for Students with Autism Spectrum Disorder: A Best-Evidence Synthesis

Science.gov (United States)

King, Seth A.; Lemons, Christopher J.; Davidson, Kimberly A.

2016-01-01

Educators need evidence-based practices to assist students with disabilities in meeting increasingly rigorous standards in mathematics. Students with autism spectrum disorder (ASD) are increasingly expected to demonstrate learning of basic and advanced mathematical concepts. This review identifies math intervention studies involving children and…

One-dimensional isothermal multicomponent diffusion-reaction model and its application to methanol synthesis over commercial Cu-based catalyst

Directory of Open Access Journals (Sweden)

Lei Kun

2015-03-01

Full Text Available The present work was a study on global reaction rate of methanol synthesis. We measured experimentally the global reaction rate in the internal recycle gradientless reactor over catalyst SC309. The diffusion-reaction model of methanol synthesis was suggested. For model we chose the hydrogenation of CO and CO2 as key reaction. CO and CO2 were key components in our model. The internal diffusion effectiveness factors of CO and CO2 in the catalyst were calculated by the numerical integration. A comparison with the experiment showed that all the absolute values of the relative error were less than 10%. The simulation results showed that decreasing reaction temperature and catalyst diameter were conducive to reduce the influence of the internal diffusion on the methanol synthesis.

Wind Profiles and Wave Spectra for Potential Wind Farms in South China Sea. Part II: Wave Spectrum Model

Directory of Open Access Journals (Sweden)

Yichao Liu

2017-01-01

Full Text Available Along with the commercialization of offshore wind energy in China, the South China Sea has been identified as ideal for constructing offshore wind farms, especially for farms consisting of floating wind turbines over deep waters. Since the wind profiles and wave spectra are somewhat primitive for the design of an offshore wind turbine, engineering models describing the wind and wave characteristics in the South China Sea area are necessary for the offshore wind energy exploitation given the meteorological, hydrological, and geographical differences between the South China Sea and the North/Norwegian Sea, where the commonly used wind profile and wave spectrum models were designated. In the present study; a series of numerical simulations were conducted to reveal the wave characteristics in the South China Sea under both typhoon and non-typhoon conditions. By analyzing the simulation results; the applicability of the Joint North Sea Wave Project (JONSWAP spectrum model; in terms of characterizing the wind-induced wave fields in the South China Sea; was discussed. In detail; the key parameters of the JONSWAP spectrum model; such as the Phillips constant; spectral width parameter; peak-enhancement factor, and high frequency tail decay; were investigated in the context of finding suitable values.

Scaling model for a speed-dependent vehicle noise spectrum

Directory of Open Access Journals (Sweden)

Giovanni Zambon

2017-06-01

Full Text Available Considering the well-known features of the noise emitted by moving sources, a number of vehicle characteristics such as speed, unladen mass, engine size, year of registration, power and fuel were recorded in a dedicated monitoring campaign performed in three different places, each characterized by different number of lanes and the presence of nearby reflective surfaces. A full database of 144 vehicles (cars was used to identify statistically relevant features. In order to compare the vehicle transit noise in different environmental condition, all 1/3-octave band spectra were normalized and analysed. Unsupervised clustering algorithms were employed to group together spectrum levels with similar profiles. Our results corroborate the well-known fact that speed is the most relevant characteristic to discriminate between different vehicle noise spectrum. In keeping with this fact, we present a new approach to predict analytically noise spectra for a given vehicle speed. A set of speed-dependent analytical functions are suggested in order to fit the normalized average spectrum profile at different speeds. This approach can be useful for predicting vehicle speed based purely on its noise spectrum pattern. The present work is complementary to the accurate analysis of noise sources based on the beamforming technique.

Bayesian modelling of the emission spectrum of the Joint European Torus Lithium Beam Emission Spectroscopy system.

Science.gov (United States)

Kwak, Sehyun; Svensson, J; Brix, M; Ghim, Y-C

2016-02-01

A Bayesian model of the emission spectrum of the JET lithium beam has been developed to infer the intensity of the Li I (2p-2s) line radiation and associated uncertainties. The detected spectrum for each channel of the lithium beam emission spectroscopy system is here modelled by a single Li line modified by an instrumental function, Bremsstrahlung background, instrumental offset, and interference filter curve. Both the instrumental function and the interference filter curve are modelled with non-parametric Gaussian processes. All free parameters of the model, the intensities of the Li line, Bremsstrahlung background, and instrumental offset, are inferred using Bayesian probability theory with a Gaussian likelihood for photon statistics and electronic background noise. The prior distributions of the free parameters are chosen as Gaussians. Given these assumptions, the intensity of the Li line and corresponding uncertainties are analytically available using a Bayesian linear inversion technique. The proposed approach makes it possible to extract the intensity of Li line without doing a separate background subtraction through modulation of the Li beam.

Dynamic plantwide modeling, uncertainty and sensitivity analysis of a pharmaceutical upstream synthesis: Ibuprofen case study

DEFF Research Database (Denmark)

Montes, Frederico C. C.; Gernaey, Krist; Sin, Gürkan

2018-01-01

A dynamic plantwide model was developed for the synthesis of the Active pharmaceutical Ingredient (API) ibuprofen, following the Hoescht synthesis process. The kinetic parameters, reagents, products and by-products of the different reactions were adapted from literature, and the different process...... operations integrated until the end process, crystallization and isolation of the ibuprofen crystals. The dynamic model simulations were validated against available measurements from literature and then used as enabling tool to analyze the robustness of design space. To this end, sensitivity of the design...... space towards input disturbances and process uncertainties (from physical and model parameters) is studied using Monte Carlo simulations. The results quantify the uncertainty of the quality of product attributes, with particular focus on crystal size distribution and ibuprofen crystalized. The ranking...

The solid-state terahertz spectrum of MDMA (Ecstasy) - A unique test for molecular modeling assignments

Science.gov (United States)

Allis, Damian G.; Hakey, Patrick M.; Korter, Timothy M.

2008-10-01

The terahertz (THz, far-infrared) spectrum of 3,4-methylene-dioxymethamphetamine hydrochloride (Ecstasy) is simulated using solid-state density functional theory. While a previously reported isolated-molecule calculation is noteworthy for the precision of its solid-state THz reproduction, the solid-state calculation predicts that the isolated-molecule modes account for only half of the spectral features in the THz region, with the remaining structure arising from lattice vibrations that cannot be predicted without solid-state molecular modeling. The molecular origins of the internal mode contributions to the solid-state THz spectrum, as well as the proper consideration of the protonation state of the molecule, are also considered.

ADAPTIVE TEXTURE SYNTHESIS FOR LARGE SCALE CITY MODELING

Directory of Open Access Journals (Sweden)

G. Despine

2015-02-01

Full Text Available Large scale city models textured with aerial images are well suited for bird-eye navigation but generally the image resolution does not allow pedestrian navigation. One solution to face this problem is to use high resolution terrestrial photos but it requires huge amount of manual work to remove occlusions. Another solution is to synthesize generic textures with a set of procedural rules and elementary patterns like bricks, roof tiles, doors and windows. This solution may give realistic textures but with no correlation to the ground truth. Instead of using pure procedural modelling we present a method to extract information from aerial images and adapt the texture synthesis to each building. We describe a workflow allowing the user to drive the information extraction and to select the appropriate texture patterns. We also emphasize the importance to organize the knowledge about elementary pattern in a texture catalogue allowing attaching physical information, semantic attributes and to execute selection requests. Roofs are processed according to the detected building material. Façades are first described in terms of principal colours, then opening positions are detected and some window features are computed. These features allow selecting the most appropriate patterns from the texture catalogue. We experimented this workflow on two samples with 20 cm and 5 cm resolution images. The roof texture synthesis and opening detection were successfully conducted on hundreds of buildings. The window characterization is still sensitive to the distortions inherent to the projection of aerial images onto the facades.

Energy spectrum scaling in an agent-based model for bacterial turbulence

Science.gov (United States)

Mikel-Stites, Maxwell; Staples, Anne

2017-11-01

Numerous models have been developed to examine the behavior of dense bacterial swarms and to explore the visually striking phenomena of bacterial turbulence. Most models directly impose fluid dynamics physics, either by modeling the active matter as a fluid or by including interactions between the bacteria and a fluid. In this work, however, the `turbulence' is solely an emergent property of the collective behavior of the bacterial population, rather than a consequence of imposed fluid dynamics physical modeling. The system is simulated using a two dimensional Vicsek-style model, with the addition of individual repulsion to simulate bacterial collisions and physical interactions, and without the common flocking or sensing behaviors. Initial results indicate the presence of k-1 scaling in a portion of the kinetic energy spectrum that can be considered analogous to the inertial subrange in turbulent energy spectra. This result suggests that the interaction of large numbers of individual active bacteria may also be a contributing factor in the emergence of fluid dynamics phenomena, in addition to the physical interactions between bacteria and their fluid environment.

Physically Inspired Models for the Synthesis of Stiff Strings with Dispersive Waveguides

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Testa I

2004-01-01

Full Text Available We review the derivation and design of digital waveguides from physical models of stiff systems, useful for the synthesis of sounds from strings, rods, and similar objects. A transform method approach is proposed to solve the classic fourth-order equations of stiff systems in order to reduce it to two second-order equations. By introducing scattering boundary matrices, the eigenfrequencies are determined and their dependency is discussed for the clamped, hinged, and intermediate cases. On the basis of the frequency-domain physical model, the numerical discretization is carried out, showing how the insertion of an all-pass delay line generalizes the Karplus-Strong algorithm for the synthesis of ideally flexible vibrating strings. Knowing the physical parameters, the synthesis can proceed using the generalized structure. Another point of view is offered by Laguerre expansions and frequency warping, which are introduced in order to show that a stiff system can be treated as a nonstiff one, provided that the solutions are warped. A method to compute the all-pass chain coefficients and the optimum warping curves from sound samples is discussed. Once the optimum warping characteristic is found, the length of the dispersive delay line to be employed in the simulation is simply determined from the requirement of matching the desired fundamental frequency. The regularization of the dispersion curves by means of optimum unwarping is experimentally evaluated.

Modeling the absorption spectrum of the permanganate ion in vacuum and in aqueous solution

DEFF Research Database (Denmark)

Olsen, Jógvan Magnus Haugaard; Hedegård, Erik Donovan

2017-01-01

The absorption spectrum of the MnO4(-) ion has been a test-bed for quantum-chemical methods over the last decades. Its correct description requires highly-correlated multiconfigurational methods, which are incompatible with the inclusion of finite-temperature and solvent effects due to their high...... by employing the polarizable embedding (PE) model combined with a range-separated complete active space short-range density functional theory method (CAS-srDFT). Finite-temperature effects are taken into account by averaging over structures obtained from ab initio molecular dynamics simulations. The explicit...... treatment of finite-temperature and solvent effects facilitates the interpretation of the bands in the low-energy region of the MnO4(-) absorption spectrum, whose assignment has been elusive....

Synthesis of humidity sensitive zinc stannate nanomaterials and modelling of Freundlich adsorption isotherm model

Science.gov (United States)

Sharma, Alfa; Kumar, Yogendra; Shirage, Parasharam M.

2018-04-01

The chemi-resistive humidity sensing behaviour of as prepared and annealed ZnSnO3 nanoparticles synthesized using a wet chemical synthesis method was investigated. The effect of stirring temperature over the evolution of varied nanomorphology of zinc stannate is in accordance to Ostwald's ripening law. At room temperature, an excellent humidity sensitivity of ˜800% and response/recovery time of 70s./102s. is observed for ZnSnO3 sample within 08-97% relative humidity range. The experimental data observed over the entire range of RH values well fitted with the Freundlich adsorption isotherm model, and revealing two distinct water adsorption regimes. The excellent humidity sensitivity observed in the nanostructures is attributed to Grotthuss mechanism considering the availability and distribution of available adsorption sites. This present result proposes utilization of low cost synthesis technique of ZnSnO3 holds the promising capabilities as potential candidate for the fabrication of next generation humidity sensors.

Synthesis and luminescence properties of Eu -activated Ca4Mg5 ...

Indian Academy of Sciences (India)

Abstract. Ca4Mg5(PO4)6:Eu2+ blue-emitting phosphor was synthesized by the combustion-assisted synthesis method under reductive atmosphere. The products were characterized by powder X-ray diffraction (XRD), trans- mission electron microscopy (TEM) and photoluminescence (PL) spectrum. XRD analysis confirmed ...

Providing the meta-model of development of competency using the meta-ethnography approach: Part 2. Synthesis of the available competency development models

Directory of Open Access Journals (Sweden)

Shahram Yazdani

2016-12-01

Full Text Available Background and Purpose: ConsideringBackground and Purpose: Considering the importance and necessity of competency-based education at a global level and with respect to globalization and the requirement of minimum competencies in medical fields, medical education communities and organizations worldwide have tried to determine the competencies, present frameworks and education models to respond to be sure of the ability of all graduates. In the literature, we observed numerous competency development models that refer to the same issues with different terminologies. It seems that evaluation and synthesis of all these models can finally result in designing a comprehensive meta-model for competency development.Methods: Meta-ethnography is a useful method for synthesis of qualitative research that is used to develop models that interpret the results in several studies. Considering that the aim of this study is to ultimately provide a competency development meta-model, in the previous section of the study, the literature review was conducted to achieve competency development models. Models obtained through the search were studied in details, and the key concepts of the models and overarching concepts were extracted in this section, models’ concepts were reciprocally translated and the available competency development models were synthesized.Results: A presentation of the competency development meta-model and providing a redefinition of the Dreyfus brothers model.Conclusions: Given the importance of competency-based education at a global level and the need to review curricula and competency-based curriculum design, it is required to provide competency development as well as meta-model to be the basis for curriculum development. As there are a variety of competency development models available, in this study, it was tried to develop the curriculum using them.Keywords: Meta-ethnography, Competency development, Meta-model, Qualitative synthesis

Modelling of discrete TDS-spectrum of hydrogen desorption

Science.gov (United States)

Rodchenkova, Natalia I.; Zaika, Yury V.

2015-12-01

High concentration of hydrogen in metal leads to hydrogen embrittlement. One of the methods to evaluate the hydrogen content is the method of thermal desorption spectroscopy (TDS). As the sample is heated under vacuumization, atomic hydrogen diffuses inside the bulk and is desorbed from the surface in the molecular form. The extraction curve (measured by a mass-spectrometric analyzer) is recorded. In experiments with monotonous external heating it is observed that background hydrogen fluxes from the extractor walls and fluxes from the sample cannot be reliably distinguished. Thus, the extraction curve is doubtful. Therefore, in this case experimenters use discrete TDS-spectrum: the sample is removed from the analytical part of the device for the specified time interval, and external temperature is then increased stepwise. The paper is devoted to the mathematical modelling and simulation of experimental studies. In the corresponding boundary-value problem with nonlinear dynamic boundary conditions physical- chemical processes in the bulk and on the surface are taken into account: heating of the sample, diffusion in the bulk, hydrogen capture by defects, penetration from the bulk to the surface and desorption. The model aimed to analyze the dynamics of hydrogen concentrations without preliminary artificial sample saturation. Numerical modelling allows to choose the point on the extraction curve that corresponds to the initial quantity of the surface hydrogen, to estimate the values of the activation energies of diffusion, desorption, parameters of reversible capture and hydride phase decomposition.

Modelling of discrete TDS-spectrum of hydrogen desorption

International Nuclear Information System (INIS)

Rodchenkova, Natalia I; Zaika, Yury V

2015-01-01

High concentration of hydrogen in metal leads to hydrogen embrittlement. One of the methods to evaluate the hydrogen content is the method of thermal desorption spectroscopy (TDS). As the sample is heated under vacuumization, atomic hydrogen diffuses inside the bulk and is desorbed from the surface in the molecular form. The extraction curve (measured by a mass-spectrometric analyzer) is recorded. In experiments with monotonous external heating it is observed that background hydrogen fluxes from the extractor walls and fluxes from the sample cannot be reliably distinguished. Thus, the extraction curve is doubtful. Therefore, in this case experimenters use discrete TDS-spectrum: the sample is removed from the analytical part of the device for the specified time interval, and external temperature is then increased stepwise. The paper is devoted to the mathematical modelling and simulation of experimental studies. In the corresponding boundary-value problem with nonlinear dynamic boundary conditions physical- chemical processes in the bulk and on the surface are taken into account: heating of the sample, diffusion in the bulk, hydrogen capture by defects, penetration from the bulk to the surface and desorption. The model aimed to analyze the dynamics of hydrogen concentrations without preliminary artificial sample saturation. Numerical modelling allows to choose the point on the extraction curve that corresponds to the initial quantity of the surface hydrogen, to estimate the values of the activation energies of diffusion, desorption, parameters of reversible capture and hydride phase decomposition. (paper)

Eluding the Physical Constraints in a Nonlinear Interaction Sound Synthesis Model for Gesture Guidance

Directory of Open Access Journals (Sweden)

Etienne Thoret

2016-06-01

Full Text Available In this paper, a flexible control strategy for a synthesis model dedicated to nonlinear friction phenomena is proposed. This model enables to synthesize different types of sound sources, such as creaky doors, singing glasses, squeaking wet plates or bowed strings. Based on the perceptual stance that a sound is perceived as the result of an action on an object we propose a genuine source/filter synthesis approach that enables to elude physical constraints induced by the coupling between the interacting objects. This approach makes it possible to independently control and freely combine the action and the object. Different implementations and applications related to computer animation, gesture learning for rehabilitation and expert gestures are presented at the end of this paper.

Hybrid neural network model for simulating sorbitol synthesis by glucose-fructose oxidoreductase in Zymomonas mobilis CP4

Directory of Open Access Journals (Sweden)

Bravo S.

2004-01-01

Full Text Available A hybrid neural network model for simulating the process of enzymatic reduction of fructose to sorbitol process catalyzed by glucose-fructose oxidoreductase in Zymomonas mobilis CP4 is presented. Data used to derive and validate the model was obtained from experiments carried out under different conditions of pH, temperature and concentrations of both substrates (glucose and fructose involved in the reaction. Sonicated and lyophilized cells were used as source of the enzyme. The optimal pH for sorbitol synthesis at 30º C is 6.5. For a value of pH of 6, the optimal temperature is 35º C. The neural network in the model computes the value of the kinetic relationship. The hybrid neural network model is able to simulate changes in the substrates and product concentrations during sorbitol synthesis under pH and temperature conditions ranging between 5 and 7.5 and 25 and 40º C, respectively. Under these conditions the rate of sorbitol synthesis shows important differences. Values computed using the hybrid neural network model have an average error of 1.7·10-3 mole.

White Emitting ZnS Nanocrystals: Synthesis and Spectrum Characterization

International Nuclear Information System (INIS)

Qing-Song, Huang; Dong-Qing, Dong; Jian-Ping, Xu; Xiao-Song, Zhang; Hong-Min, Zhang; Lan, Li

2010-01-01

Spherical organic-bonded ZnS nanocrystals with 4.0±0.2 nm in diameter are synthesized by a liquid-solid-solution method. The photoluminescence spectrum of sample ([S 2− ]/[Zn 2+ ] = 1.0) shows a strong white emission with a peak at 490 nm and ∼ 170 nm full widths at half maximum. By Gauss fitting, the white emission is attributed to the overlap of a blue emission and a green-yellow emission, originating from electronic transitions from internal S 2− vacancies level to valence band and to the internal Zn 2+ vacancy level, respectively. After sealingZnS nanocrystals onto InGaN chips, the device shows CIE coordinates of (0.29,0.30), which indicates their potential applications for white light emitting diodes

Spectrum estimation method based on marginal spectrum

International Nuclear Information System (INIS)

Cai Jianhua; Hu Weiwen; Wang Xianchun

2011-01-01

FFT method can not meet the basic requirements of power spectrum for non-stationary signal and short signal. A new spectrum estimation method based on marginal spectrum from Hilbert-Huang transform (HHT) was proposed. The procession of obtaining marginal spectrum in HHT method was given and the linear property of marginal spectrum was demonstrated. Compared with the FFT method, the physical meaning and the frequency resolution of marginal spectrum were further analyzed. Then the Hilbert spectrum estimation algorithm was discussed in detail, and the simulation results were given at last. The theory and simulation shows that under the condition of short data signal and non-stationary signal, the frequency resolution and estimation precision of HHT method is better than that of FFT method. (authors)

Technology library modeling for information-driven circuit synthesis

NARCIS (Netherlands)

Jozwiak, L.; Bieganski, S.J.

2008-01-01

Due to weaknesses in circuit synthesis methods used in todaypsilas CAD tools, the opportunities created by modern microelectronic technology cannot effectively be exploited. This paper considers major issues and requirements of circuit synthesis for the nano CMOS technologies, and discusses our new

[Models for intervention in autism spectrum disorders: Denver and SCERTS].

Science.gov (United States)

Forment-Dasca, C

2017-02-24

Given the increased prevalence of diagnoses of autism in recent years, the growing amount of research on models with which to work with people with autism spectrum disorders (ASD) has led to the development of different techniques and methods enabling better results to be obtained. As a result, it has become possible to help improve many of the symptoms that prevent people with this diagnosis and their families from leading a normal life. To review two intervention models specifically designed for working with persons with ASD. The review first examines an early intervention model, the Early Start Denver Model, which consists in a checklist for children with ASD aged from 12 to 48 months, based on their progress. The SCERTS model is also reviewed. Unlike the Denver, this model presents goals that must be worked on throughout the entire lifespan of those with ASD. In the absence of further results from scientific evidence-based practice regarding the two models reviewed here, it can be concluded that there is no single standardised model and that children with difficulties in joint attention and imitation need to be referred at an early stage, as well as working together with the families. Thus, to perform a correct intervention it is necessary to take into account evidence-based practice and for the therapist to have a deep knowledge, respect and understanding of children with ASD and of their families.

Synthesis, model and stability of helically coiled carbon nanotubes

DEFF Research Database (Denmark)

Fejes, Dora; Raffai, Manuella; Hernadi, Klara

2013-01-01

. Our experiments focused on the production and development of catalysts for the synthesis of helically coiled CNTs (carbon nanotubes). The catalysts were tested in the decomposition of acetylene by CCVD (Catalytic Chemical Vapor Deposition) method. The carbon deposit was imaged by TEM (Transmission......Structural model of helically coiled carbon nanotubes is proposed. It is constructed by means of topological coordinate method. Relaxation and cohesive energy calculation are performed by molecular mechanics, using second-generation bond order potential for hydrocarbons introduced by D. W. Brenner...

Inhibiting corticosterone synthesis during fear memory formation exacerbates cued fear extinction memory deficits within the single prolonged stress model.

Science.gov (United States)

Keller, Samantha M; Schreiber, William B; Stanfield, Briana R; Knox, Dayan

2015-01-01

Using the single prolonged stress (SPS) animal model of post-traumatic stress disorder (PTSD), previous studies suggest that enhanced glucocorticoid receptor (GR) expression leads to cued fear extinction retention deficits. However, it is unknown how the endogenous ligand of GRs, corticosterone (CORT), may contribute to extinction retention deficits in the SPS model. Given that CORT synthesis during fear learning is critical for fear memory consolidation and SPS enhances GR expression, CORT synthesis during fear memory formation could strengthen fear memory in SPS rats by enhancing GR activation during fear learning. In turn, this could lead to cued fear extinction retention deficits. We tested the hypothesis that CORT synthesis during fear learning leads to cued fear extinction retention deficits in SPS rats by administering the CORT synthesis inhibitor metyrapone to SPS and control rats prior to fear conditioning, and observed the effect this had on extinction memory. Inhibiting CORT synthesis during fear memory formation in control rats tended to decrease cued freezing, though this effect never reached statistical significance. Contrary to our hypothesis, inhibiting CORT synthesis during fear memory formation disrupted extinction retention in SPS rats. This finding suggests that even though SPS exposure leads to cued fear extinction memory deficits, CORT synthesis during fear memory formation enhances extinction retention in SPS rats. This suggests that stress-induced CORT synthesis in previously stressed rats can be beneficial. Copyright © 2015 Elsevier B.V. All rights reserved.

Solitary mammals provide an animal model for autism spectrum disorders.

Science.gov (United States)

Reser, Jared Edward

2014-02-01

Species of solitary mammals are known to exhibit specialized, neurological adaptations that prepare them to focus working memory on food procurement and survival rather than on social interaction. Solitary and nonmonogamous mammals, which do not form strong social bonds, have been documented to exhibit behaviors and biomarkers that are similar to endophenotypes in autism. Both individuals on the autism spectrum and certain solitary mammals have been reported to be low on measures of affiliative need, bodily expressiveness, bonding and attachment, direct and shared gazing, emotional engagement, conspecific recognition, partner preference, separation distress, and social approach behavior. Solitary mammals also exhibit certain biomarkers that are characteristic of autism, including diminished oxytocin and vasopressin signaling, dysregulation of the endogenous opioid system, increased Hypothalamic-pituitary-adrenal axis (HPA) activity to social encounters, and reduced HPA activity to separation and isolation. The extent of these similarities suggests that solitary mammals may offer a useful model of autism spectrum disorders and an opportunity for investigating genetic and epigenetic etiological factors. If the brain in autism can be shown to exhibit distinct homologous or homoplastic similarities to the brains of solitary animals, it will reveal that they may be central to the phenotype and should be targeted for further investigation. Research of the neurological, cellular, and molecular basis of these specializations in other mammals may provide insight for behavioral analysis, communication intervention, and psychopharmacology for autism.

CHAM: a fast algorithm of modelling non-linear matter power spectrum in the sCreened HAlo Model

Science.gov (United States)

Hu, Bin; Liu, Xue-Wen; Cai, Rong-Gen

2018-05-01

We present a fast numerical screened halo model algorithm (CHAM, which stands for the sCreened HAlo Model) for modelling non-linear power spectrum for the alternative models to Λ cold dark matter. This method has three obvious advantages. First of all, it is not being restricted to a specific dark energy/modified gravity model. In principle, all of the screened scalar-tensor theories can be applied. Secondly, the least assumptions are made in the calculation. Hence, the physical picture is very easily understandable. Thirdly, it is very predictable and does not rely on the calibration from N-body simulation. As an example, we show the case of the Hu-Sawicki f(R) gravity. In this case, the typical CPU time with the current parallel PYTHON script (eight threads) is roughly within 10 min. The resulting spectra are in a good agreement with N-body data within a few percentage accuracy up to k ˜ 1 h Mpc-1.

Model for spatial synthesis of automated control system of the GCR type reactor; Model za prostornu sintezu sistema automatskog upravljanja reaktora GCR tipa

Energy Technology Data Exchange (ETDEWEB)

Lazarevic, B; Matausek, M [Institut za nuklearne nauke ' Boris Kidric' , Vinca, Belgrade (Yugoslavia)

1966-07-01

This paper describes the model which was developed for synthesis of spatial distribution of automated control elements in the reactor. It represents a general reliable mathematical model for analyzing transition states and synthesis of the automated control and regulation systems of GCR type reactors. One-dimensional system was defined under assumption that the time dependence of parameters of the neutron diffusion equation are identical in the total volume of the reactor and that spatial distribution of neutrons is time independent. It is shown that this assumption is satisfactory in case of short term variations which are relevant for safety analysis.

Development of a model for the synthesis of unsaturated polyester by reactive distillation

NARCIS (Netherlands)

Shah, M.R.; Zondervan, E.; Oudshoorn, M.L.; Haan, de A.B.; Haan, de A.B.; Kooijman, H.; Górak, A.

2010-01-01

Traditionally polyester production is done in a batch reactor equipped with a separation column for batch distillation. A promising alternative for the intensification of this process is reactive distillation. In this paper, a reactive distillation model is developed for the synthesis of an

Effectiveness of a Novel Community-Based Early Intervention Model for Children with Autistic Spectrum Disorder

Science.gov (United States)

Smith, Isabel M.; Koegel, Robert L.; Koegel, Lynn K.; Openden, Daniel A.; Fossum, Kristin L.; Bryson, Susan E.

2010-01-01

The Nova Scotia early intensive behavior intervention model--NS EIBI (Bryson et al., 2007) for children with autistic spectrum disorders was designed to be feasible and sustainable in community settings. It combines parent training and naturalistic one-to-one behavior intervention employing Pivotal Response Treatment--PRT (R. Koegel & Koegel,…

Using Video Modeling as an Anti-bullying Intervention for Children with Autism Spectrum Disorder.

Science.gov (United States)

Rex, Catherine; Charlop, Marjorie H; Spector, Vicki

2018-03-07

In the present study, we used a multiple baseline design across participants to assess the efficacy of a video modeling intervention to teach six children with autism spectrum disorder (ASD) to assertively respond to bullying. During baseline, the children made few appropriate responses upon viewing video clips of bullying scenarios. During the video modeling intervention, participants viewed videos of models assertively responding to three types of bullying: physical, verbal bullying, and social exclusion. Results indicated that all six children learned through video modeling to make appropriate assertive responses to bullying scenarios. Four of the six children demonstrated learning in the in situ bullying probes. The results are discussed in terms of an intervention for victims of bullying with ASD.

Quantum game application to spectrum scarcity problems

Science.gov (United States)

Zabaleta, O. G.; Barrangú, J. P.; Arizmendi, C. M.

2017-01-01

Recent spectrum-sharing research has produced a strategy to address spectrum scarcity problems. This novel idea, named cognitive radio, considers that secondary users can opportunistically exploit spectrum holes left temporarily unused by primary users. This presents a competitive scenario among cognitive users, making it suitable for game theory treatment. In this work, we show that the spectrum-sharing benefits of cognitive radio can be increased by designing a medium access control based on quantum game theory. In this context, we propose a model to manage spectrum fairly and effectively, based on a multiple-users multiple-choice quantum minority game. By taking advantage of quantum entanglement and quantum interference, it is possible to reduce the probability of collision problems commonly associated with classic algorithms. Collision avoidance is an essential property for classic and quantum communications systems. In our model, two different scenarios are considered, to meet the requirements of different user strategies. The first considers sensor networks where the rational use of energy is a cornerstone; the second focuses on installations where the quality of service of the entire network is a priority.

The speech-based envelope power spectrum model (sEPSM) family: Development, achievements, and current challenges

DEFF Research Database (Denmark)

Relano-Iborra, Helia; Chabot-Leclerc, Alexandre; Scheidiger, Christoph

2017-01-01

have extended the predictive power of the original model to a broad range of conditions. This contribution presents the most recent developments within the sEPSM “family:” (i) A binaural extension, the B-sEPSM [Chabot-Leclerc et al. (2016). J. Acoust. Soc. Am. 140(1), 192-205] which combines better......Intelligibility models provide insights regarding the effects of target speech characteristics, transmission channels and/or auditory processing on the speech perception performance of listeners. In 2011, Jørgensen and Dau proposed the speech-based envelope power spectrum model [sEPSM, Jørgensen...

Spectrum 101: An Introduction to Spectrum Management

Science.gov (United States)

2004-03-01

produces a Joint Restricted Frequency List (JRFL). The JFRL consolidates and classifies the spectrum uses that are most critical to operations and to...Management Office JRFL Joint Restricted Frequency List JSC Joint Spectrum Center JSIR Joint Spectrum Interference Resolution JSME Joint Spectrum...Multifunctional Information Distribution System MILSATCOM Military Satellite Communications MOA Memorandum of Agreement MRFL Master Radio Frequency

Application of the model of the relativistic anti-loss-cone distribution to ECE spectrum in discharge applying LH wave

International Nuclear Information System (INIS)

Sato, Masayasu; Yokomizo, Hideaki

1987-11-01

The electron cyclotron emission (ECE) is dominated from supra-thermal electron in discharge applying LH wave. We obtain informations of supra-thermal electron by applying the model of the relativistic anti-loss-cone distribution to ECE spectrum in the discharge. In this model, the emission perpendicular to the magnetic field are considered. The frequency range is considered to be well above the plasma and electron cyclotron frequencies, thus collective effects can be neglected. The electron distribution is assumed to be anisotropic in the velocity space and strongly extended in the direction parallel to the magnetic field, namely the relativistic anti-loss-cone distribution. The informations of supra-thermal electron are obtained by the following way. The temperature and density of the supra-thermal electron and the anti-loss-cone angle are obtained from the power spectrum of LH wave launched, the measured slope of the spectrum of ECE and the spectral radiance of ECE. (author)

Beyond the Spectrum: Rethinking Autism

Directory of Open Access Journals (Sweden)

Heather Thomas

2017-03-01

Full Text Available The "spectrum" has become the dominant metaphor for conceptualizing autism, with fundamental consequences for notions of disability, diversity, and normality. In this article, we draw on ethnographic research with autistic communities to explore how the notion of the autism spectrum has become a focus of explicit identification, reflection, and contestation. To further this inquiry, we place these debates into conversation with earlier debates regarding another spectrum—the Kinsey Scale, a "spectrum" for conceptualizing sexual orientation that first appeared in 1948 but has been critiqued since the 1970s. How might responses to the Kinsey Scale (like the Klein Grid contribute to rethinking the autism spectrum? This is a question about the cultural and political implications of metaphors and conceptual models. It is of broad importance because the spectrum metaphor is being extended to a range of conditions beyond autism itself. Our goal is thus to build on insights from sexuality studies as well as the insights of autistic persons, advocates, and researchers who wish to forestall the naturalization of "the spectrum." In doing so, we seek to contribute to a discussion of what alternative frameworks might bring to questions of social justice, ability, and human flourishing.

On Absence of Pure Singular Spectrum of Random Perturbations and in Anderson Model at Low Disorde

CERN Document Server

Grinshpun, V

2006-01-01

Absence of singular component, with probability one, in the conductivity spectra of bounded random perturbations of multidimensional finite-difference Hamiltonians, is for the first time rigorously established under certain conditions ensuring either absence of pure point, or absence of pure absolutely continuous component in the corresponding regions of spectra. The main technical tool applied is the theory of rank-one perturbations of singular spectra. The respective new result (the non-mixing property) is applied to establish existence and bounds of the (non-empty) pure absolutely continuous component in the spectrum of the Anderson model with bounded random potential in dimension 2 at low disorder. The new (1999) result implies, via the trace-class perturbation analysis, the Anderson model with the unbounded potential to have only pure point spectrum (complete system of localized wave-functions) with probability one in arbitrary dimension. The new technics, based on the resolvent reduction formula, and ex...

Green synthesis and characterisation of platinum nanoparticles using quail egg yolk

Science.gov (United States)

Nadaroglu, Hayrunnisa; Gungor, Azize Alayli; Ince, Selvi; Babagil, Aynur

2017-02-01

Nanotechnology is extensively used in all parts today. Therefore, nano synthesis is also significant in all explored areas. The results of studies conducted have revealed that nanoparticle synthesis is performed by using both chemical and physical methods. It is well known that these syntheses are carried out at high charge, pressure and temperature in harsh environments. Therefore, this study investigated green synthesis method that sustains more mild conditions. In this study, quail egg yolk having high vitamin and protein content was prepared for green synthesis reaction and used for the synthesis of platinum nanoparticles in the reaction medium. Reaction situations were optimised as a function of pH, temperature, time and concentration by using quail egg yolk. The results showed that the highest platinum nanoparticles were synthesised at 20 °C and pH 6.0 for 4 h. Also, optimal concentration of metal ions was established as 0.5 mM. The synthesised platinum nanoparticles were characterised by using UV spectrum, X-ray diffraction and scanning electron microscope.

Autism spectrum disorders: toward a gendered embodiment model.

Science.gov (United States)

Cheslack-Postava, Keely; Jordan-Young, Rebecca M

2012-06-01

One of the most consistent observations in the epidemiology of autism spectrum disorders (ASD) is the preponderance of male cases. A few hypotheses have been put forth which attempt to explain this divergence in terms of sex-linked biology, with limited success. Feminist epidemiologists suggest the importance of investigating specific mechanisms for male-female differences in health outcomes, which may include sex-linked biology and/or gender relations, as well as complex biosocial interactions. Neither domain has been systematically investigated for autism, and the possible role of gender has been particularly neglected. In this article, we posit hypotheses about how social processes based on perception of persons as male or female, particularly patterns of social and physical interaction in early development, may affect the observed occurrence and diagnosis of ASD. We gesture toward an embodiment model, incorporating hypotheses about initial biological vulnerabilities to autism--which may or may not be differentially distributed in relation to sex biology--and their interactions with gender relations, which are demonstrably different for male and female infants. Toward building such a model, we first review the epidemiology of ASD with an eye toward male-female differences, then present a theory of gender as a "pervasive developmental environment" with relevance for the excess burden of autism among males. Finally, we suggest research strategies to further investigate this issue. Copyright © 2011 Elsevier Ltd. All rights reserved.

Inertial-range spectrum of whistler turbulence

Directory of Open Access Journals (Sweden)

Y. Narita

2010-02-01

Full Text Available We develop a theoretical model of an inertial-range energy spectrum for homogeneous whistler turbulence. The theory is a generalization of the Iroshnikov-Kraichnan concept of the inertial-range magnetohydrodynamic turbulence. In the model the dispersion relation is used to derive scaling laws for whistler waves at highly oblique propagation with respect to the mean magnetic field. The model predicts an energy spectrum for such whistler waves with a spectral index −2.5 in the perpendicular component of the wave vector and thus provides an interpretation about recent discoveries of the second inertial-range of magnetic energy spectra at high frequencies in the solar wind.

Spectrum

DEFF Research Database (Denmark)

Høgfeldt Hansen, Leif

2016-01-01

The publication functions as a proces description of the development and construction of an urban furniture SPECTRUM in the city of Gwangju, Republic of Korea. It is used as the cataloque for the exhibition of Spectrum.......The publication functions as a proces description of the development and construction of an urban furniture SPECTRUM in the city of Gwangju, Republic of Korea. It is used as the cataloque for the exhibition of Spectrum....

Synthesis of sulfonimidamides from sulfinamides by oxidation with N-chlorosuccinimide

Directory of Open Access Journals (Sweden)

Bolm Carsten

2007-09-01

Full Text Available Abstract Background The synthesis of sulfonimidamides involves the nucleophilic substitution of a sulfonimidoyl chloride with an amine. However, only four chlorinating systems have been reported for the preparation of the sulfonimidoyl chloride intermediates. Whereas some of them have shown a rather limited substrate spectrum, the most versatile and commonly used tert-butyl hypochlorite is known to be explosive. To establish alternative methods for the synthesis of these molecules is therefore desirable. Results The preparation of various p-tolylsulfonimidamides through the reaction of the corresponding N-protected p-tolylsulfinamides and a number of amines in the presence of N-chlorosuccinimide was achieved at room temperature in 50–97% yield. Conclusion A convenient alternative procedure for the synthesis of sulfonimidamides from sulfinamides and various amines and sulfonamides using N-chlorosuccinimide as halogenating agent has been developed.

Autism spectrum disorder model mice: Focus on copy number variation and epigenetics.

Science.gov (United States)

Nakai, Nobuhiro; Otsuka, Susumu; Myung, Jihwan; Takumi, Toru

2015-10-01

Autism spectrum disorder (ASD) is gathering concerns in socially developed countries. ASD is a neuropsychiatric disorder of genetic origin with high prevalence of 1%-2%. The patients with ASD characteristically show impaired social skills. Today, many genetic studies identify numerous susceptible genes and genetic loci associated with ASD. Although some genetic factors can lead to abnormal brain function linked to ASD phenotypes, the pathogenic mechanism of ASD is still unclear. Here, we discuss a new mouse model for ASD as an advanced tool to understand the mechanism of ASD.

Empirical wind retrieval model based on SAR spectrum measurements

Science.gov (United States)

Panfilova, Maria; Karaev, Vladimir; Balandina, Galina; Kanevsky, Mikhail; Portabella, Marcos; Stoffelen, Ad

The present paper considers polarimetric SAR wind vector applications. Remote-sensing measurements of the near-surface wind over the ocean are of great importance for the understanding of atmosphere-ocean interaction. In recent years investigations for wind vector retrieval using Synthetic Aperture Radar (SAR) data have been performed. In contrast with scatterometers, a SAR has a finer spatial resolution that makes it a more suitable microwave instrument to explore wind conditions in the marginal ice zones, coastal regions and lakes. The wind speed retrieval procedure from scatterometer data matches the measured radar backscattering signal with the geophysical model function (GMF). The GMF determines the radar cross section dependence on the wind speed and direction with respect to the azimuthal angle of the radar beam. Scatterometers provide information on wind speed and direction simultaneously due to the fact that each wind vector cell (WVC) is observed at several azimuth angles. However, SAR is not designed to be used as a high resolution scatterometer. In this case, each WVC is observed at only one single azimuth angle. That is why for wind vector determination additional information such as wind streak orientation over the sea surface is required. It is shown that the wind vector can be obtained using polarimetric SAR without additional information. The main idea is to analyze the spectrum of a homogeneous SAR image area instead of the backscattering normalized radar cross section. Preliminary numerical simulations revealed that SAR image spectral maxima positions depend on the wind vector. Thus the following method for wind speed retrieval is proposed. In the first stage of the algorithm, the SAR spectrum maxima are determined. This procedure is carried out to estimate the wind speed and direction with ambiguities separated by 180 degrees due to the SAR spectrum symmetry. The second stage of the algorithm allows us to select the correct wind direction

On Properties of Impurity Spectrum in the Disordered Exactly Solvable Model

CERN Document Server

Grinshpun, V

2006-01-01

The random point interaction Hamiltonian (H) is considered on L^2(R^d), d=2, or d=3. Existence and certain bounds of the non-empty pure point component and exponential decay of the corresponding eigenfunctions with probability 1, within region of impurity spectrum of H, are rigorously established. In order to prove the localization result, the structure of the generalized eigenfunctions of H is explicitly described, and the relation between its spectral properties, and the properties of spectra of finite-difference infinite-order operators on l^2(Z^d), is established. The multiscale analysis scheme is applied to investigate the point spectrum of finite-difference operators. In addition, the generalized spectral theorem, and absolute continuity of the integrated density of states of H at the negative (impurity) part of the spectrum, rigorously proved. Applications of the new approximation scheme include straightforward analysis of absolutely continuous conductivity spectrum, subject to a possible separate publ...

Interventions to Support Social Interaction in Children with Autism Spectrum Disorders: A Systematic Review of Single Case Studies

Science.gov (United States)

Ozuna, Jennifer; Mavridis, Alexis; Hott, Brittany L.

2015-01-01

Social interaction is a core deficit in individuals with autism spectrum disorder (ASD). Therefore, parents and teachers need effective interventions to support students with ASD. This synthesis provides a quantitative analysis of single-subject studies that examine interventions to support social interactions in children with ASD. Results suggest…

The dielectric properties of biological tissues: III. Parametric models for the dielectric spectrum of tissues

International Nuclear Information System (INIS)

Gabriel, S.; Lau, R.W.; Gabriel, C.

1996-01-01

A parametric model was developed to describe the variation of dielectric properties of tissues as a function of frequency. The experimental spectrum from 10 Hz to 100 GHz was modelled with four dispersion regions. The development of the model was based on recently acquired data, complemented by data surveyed from the literature. The purpose is to enable the prediction of dielectric data that are in line with those contained in the vast body of literature on the subject. The analysis was carried out on a Microsoft Excel spreadsheet. Parameters are given for 17 tissue types. (author)

Synthesis centers as critical research infrastructure

Science.gov (United States)

Baron, Jill S.; Specht, Alison; Garnier, Eric; Bishop, Pamela; Campbell, C. Andrew; Davis, Frank W.; Fady, Bruno; Field, Dawn; Gross, Louis J.; Guru, Siddeswara M.; Halpern, Benjamin S; Hampton, Stephanie E.; Leavitt, Peter R.; Meagher, Thomas R.; Ometto, Jean; Parker, John N.; Price, Richard; Rawson, Casey H.; Rodrigo, Allen; Sheble, Laura A.; Winter, Marten

2017-01-01

Demand for the opportunity to participate in a synthesis-center activity has increased in the years since the US National Science Foundation (NSF)–funded National Center for Ecological Analysis and Synthesis (NCEAS) opened its doors in 1995 and as more scientists across a diversity of scientific disciplines have become aware of what synthesis centers provide. The NSF has funded four synthesis centers, and more than a dozen new synthesis centers have been established around the world, some following the NSF model and others following different models suited to their national funding environment (http://synthesis-consortium.org).Scientific synthesis integrates diverse data and knowledge to increase the scope and applicability of results and yield novel insights or explanations within and across disciplines (Pickett et al. 2007, Carpenter et al. 2009). The demand for synthesis comes from the pressing societal need to address grand challenges related to global change and other issues that cut across multiple societal sectors and disciplines and from recognition that substantial added scientific value can be achieved through the synthesis-based analysis of existing data. Demand also comes from groups of scientists who see exciting opportunities to generate new knowledge from interdisciplinary and transdisciplinary collaboration, often capitalizing on the increasingly large volume and variety of available data (Kelling et al. 2009, Bishop et al. 2014, Specht et al. 2015b). The ever-changing nature of societal challenges and the availability of data with which to address them suggest there will be an expanding need for synthesis.However, we are now entering a phase in which government support for some existing synthesis centers has ended or will be ending soon, forcing those centers to close or develop new operational models, approaches, and funding streams. We argue here that synthesis centers play such a unique role in science that continued long-term public

Memory, learning and language in autism spectrum disorder

Directory of Open Access Journals (Sweden)

Jill Boucher

2018-02-01

Full Text Available Background and aims The ‘dual-systems’ model of language acquisition has been used by Ullman et al. to explain patterns of strength and weakness in the language of higher-functioning people with autism spectrum disorder. Specifically, intact declarative/explicit learning is argued to compensate for a deficit in non-declarative/implicit procedural learning, constituting an example of the so-called see-saw effect. Ullman and Pullman extended their argument concerning a see-saw effect on language in autism spectrum disorder to cover other perceived anomalies of behaviour, including impaired acquisition of social skills. The aim of this paper is to present a critique of Ullman et al.’s claims and to propose an alternative model of links between memory systems and language in autism spectrum disorder. Main contribution We argue that a four-system model of learning, in which intact semantic and procedural memory are used to compensate for weaknesses in episodic memory and perceptual learning, can better explain patterns of language ability across the autistic spectrum. We also argue that attempts to generalise the ‘impaired implicit learning/spared declarative learning’ theory to other behaviours in autism spectrum disorder are unsustainable. Conclusions Clinically significant language impairments in autism spectrum disorder are under-researched, despite their impact on everyday functioning and quality of life. The relative paucity of research findings in this area lays it open to speculative interpretation which may be misleading. Implications More research is needed into links between memory/learning systems and language impairments across the spectrum. Improved understanding should inform therapeutic intervention and contribute to investigation of the causes of language impairment in autism spectrum disorder with potential implications for prevention.

Modelling of the enzymatic kinetically controlled synthesis of cephalexin

NARCIS (Netherlands)

Schroën, C.G.P.H.; Fretz, C.B.; Bruin, de V.H.; Berendsen, W.; Moody, H.M.; Roos, E.C.; Roon, van J.L.; Kroon, P.J.; Strubel, M.; Janssen, A.E.M.; Tramper, J.

2002-01-01

In this study the influence of diffusion limitation on enzymatic kinetically controlled cephalexin synthesis from phenylglycine amide and 7-aminodeacetoxycephalosporinic acid (7-ADCA) was investigated systematically. It was found that if diffusion limitation occurred, both the synthesis/hydrolysis

Synthesis and characterization of mangan oxide coated sand from Capkala kaolin

Science.gov (United States)

Destiarti, Lia; Wahyuni, Nelly; Prawatya, Yopa Eka; Sasri, Risya

2017-03-01

Synthesis and characterization of mangan oxide coated sand from quartz sand fraction of Capkala kaolin has been conducted. There were two methods on synthesis of Mangan Oxide Coated Sand (MOCS) from Capkala Kaolin compared in this research. Characterization of MOCS was done by using Scanning Electron Microscope/Energy Dispersive X-Ray Spectrometer (SEM/EDX) and X-Ray Diffraction (XRD). The MOCS was tested to reduce phosphate in laundry waste. The result showed that the natural sand had bigger agregates and a relatively uniform structural orientation while both MOCS had heterogen structural orientation and manganese oxide formed in cluster. Manganese in first and second methods were 1,93% and 2,63%, respectively. The XRD spectrum showed clear reflections at 22,80°, 36,04°, 37,60° and a broad band at 26,62° (SiO2). Based on XRD spectrum, it can be concluded that mineral constituents of MOCS was verified corresponding to pyrolusite (MnO2). The former MOCS could reduce almost 60% while the later could reduce 70% phosphate in laundry waste.

Gas-phase plasma synthesis of free-standing silicon nanoparticles for future energy applications

NARCIS (Netherlands)

Doğan, I.; van de Sanden, M.C.M.

2016-01-01

Silicon nanoparticles (Si-NPs) are considered as possible candidates for a wide spectrum of future technological applications. Research in the last decades has shown that plasmas are one of the most suitable environments for the synthesis of Si-NPs. This review discusses the unique size-dependent

Gas-Phase Plasma Synthesis of Free-Standing Silicon Nanoparticles for Future Energy Applications

NARCIS (Netherlands)

Dogan, I.; van de Sanden, M. C. M.

2016-01-01

Silicon nanoparticles (Si-NPs) are considered as possible candidates for a wide spectrum of future technological applications. Research in the last decades has shown that plasmas are one of the most suitable environments for the synthesis of Si-NPs. This review discusses the unique size-dependent

Learning with Technology: Video Modeling with Concrete-Representational-Abstract Sequencing for Students with Autism Spectrum Disorder

Science.gov (United States)

Yakubova, Gulnoza; Hughes, Elizabeth M.; Shinaberry, Megan

2016-01-01

The purpose of this study was to determine the effectiveness of a video modeling intervention with concrete-representational-abstract instructional sequence in teaching mathematics concepts to students with autism spectrum disorder (ASD). A multiple baseline across skills design of single-case experimental methodology was used to determine the…

Green Synthesis of Ultraviolet Absorber 2-Ethylhexyl Salicylate: Experimental Design and Artificial Neural Network Modeling

Directory of Open Access Journals (Sweden)

Shang-Ming Huang

2017-11-01

Full Text Available 2-Ethylhexyl salicylate, an ultraviolet filter, is widely used to protect skin against sunlight-induced harmful effects in the cosmetic industry. In this study, the green synthesis of 2-ethylhexyl salicylate using immobilized lipase through a solvent-free and reduced pressure evaporation system was investigated. A Box–Behnken design was employed to develop an artificial neural network (ANN model. The parameters for an optimal architecture of an ANN were set out: a quick propagation algorithm, a hyperbolic tangent transfer function, 10,000 iterations, and six nodes within the hidden layer. The best-fitting performance of the ANN was determined by the coefficient of determination and the root-mean-square error between the correlation of predicted and experimental data, indicating that the ANN displayed excellent data-fitting properties. Finally, the experimental conditions of synthesis were well established with the optimal parameters to obtain a high conversion of 2-ethylhexyl salicylate. In conclusion, this study efficiently replaces the traditional solvents with a green process for the synthesis of 2-ethylhexyl salicylate to avoid environmental contamination, and this process is well-modeled by a methodological ANN for optimization, which might be a benefit for industrial production.

Relativistic jet feedback - II. Relationship to gigahertz peak spectrum and compact steep spectrum radio galaxies

Science.gov (United States)

Bicknell, Geoffrey V.; Mukherjee, Dipanjan; Wagner, Alexander Y.; Sutherland, Ralph S.; Nesvadba, Nicole P. H.

2018-04-01

We propose that Gigahertz Peak Spectrum (GPS) and Compact Steep Spectrum (CSS) radio sources are the signposts of relativistic jet feedback in evolving galaxies. Our simulations of relativistic jets interacting with a warm, inhomogeneous medium, utilizing cloud densities and velocity dispersions in the range derived from optical observations, show that free-free absorption can account for the ˜ GHz peak frequencies and low-frequency power laws inferred from the radio observations. These new computational models replace a power-law model for the free-free optical depth a more fundamental model involving disrupted log-normal distributions of warm gas. One feature of our new models is that at early stages, the low-frequency spectrum is steep but progressively flattens as a result of a broader distribution of optical depths, suggesting that the steep low-frequency spectra discovered by Callingham et al. may possibly be attributed to young sources. We also investigate the inverse correlation between peak frequency and size and find that the initial location on this correlation is determined by the average density of the warm ISM. The simulated sources track this correlation initially but eventually fall below it, indicating the need for a more extended ISM than presently modelled. GPS and CSS sources can potentially provide new insights into the phenomenon of AGN feedback since their peak frequencies and spectra are indicative of the density, turbulent structure, and distribution of gas in the host galaxy.

Radiation chemical synthesis

International Nuclear Information System (INIS)

Zagoretz, P.A.; Poluetkov, V.A.; Shostenko, A.G.

1986-01-01

The authors consider processes in radiation chemical synthesis which are being developed in various scientific-research organizations. The important advantages of radiation chlorination, viz. the lower temperature compared with the thermal method and the absence of dehydrochlorination products are discussed. The authors examine the liquid-phase chlorination of trifluorochloroethyltrichloromethyl ether to obtain the pentachloro-contining ether, trifluorodichloroethyltrichloromethyl ether. The authors discuss radiation synthesis processes that have be used formulated kinetic equations on which models have been based. It is concluded that the possibilities of preparative (micro- and low-tonnage) radiation synthesis are promising

Brief Report: Whole Blood Serotonin Levels and Gastrointestinal Symptoms in Autism Spectrum Disorder

OpenAIRE

Marler, Sarah; Ferguson, Bradley J.; Lee, Evon Batey; Peters, Brittany; Williams, Kent C.; McDonnell, Erin; Macklin, Eric A.; Levitt, Pat; Gillespie, Catherine Hagan; Anderson, George M.; Margolis, Kara Gross; Beversdorf, David Q.; Veenstra-VanderWeele, Jeremy

2016-01-01

Elevated whole blood serotonin levels are observed in more than 25 % of children with autism spectrum disorder (ASD). Co-occurring gastrointestinal (GI) symptoms are also common in ASD but have not previously been examined in relationship with hyperserotonemia, despite the synthesis of serotonin in the gut. In 82 children and adolescents with ASD, we observed a correlation between a quantitative measure of lower GI symptoms and whole blood serotonin levels. No significant association was seen...

Synthesis of a novel octapeptidolipid antibiotic

Energy Technology Data Exchange (ETDEWEB)

Levitt, R R

1986-01-01

The bacillomycins comprise a group of antifungal polypeptide antibiotic compounds closely related in terms of their physico-chemical properties, amino acid and ..beta..-amino fatty acid compositions. Iturin A, which belongs to the bacillomycins, consists of seven amino acids. Attempts to produce a ..beta..-NC/sub 15/ fatty acid in acceptable yield proved unsuccessful and was later discarded in favour of the preparation of a ..beta..-NC/sub 14/ fatty acid. The different experimental procedures used and results obtained when preparing both fatty acids are detailed. The method developed in preparing the ..beta..-NC/sub 14/ fatty acid affords a new general synthetic route for the production of ..beta..-amino fatty acids in good yield. The strategy considered in selecting which amino acid to commence the peptide synthesis with, the use in the Merrifield procedure of N-protected amino acids, coupling reagents, deprotecting and cleaving agents, and the HPLC purification procedures used for the linear and cyclic octapeptides, are all described. The /sup 1/H-NMR spectrum of the synthetic cyclic compound compared favourably with the spectrum of natural iturin A and these results are also presented. This dissertation presents the total synthesis of a novel octapeptidolipid antifungal antibiotic (iturin A analogue), utilising the Merrifield solid phase procedure. The biological activity of the synthesised and purified linear and cyclic iturin A analogues were compared with that of bacillomycin S. The test for biological activity and results obtained are described and illustrated with photographic plates.

Adjustment of the 235U Fission Spectrum

International Nuclear Information System (INIS)

GRIFFIN, PATRICK J.; WILLIAMS, J.G.

1999-01-01

The latest nuclear data are used to examine the sensitivity of the least squares adjustment of the 235 U fission spectrum to the measured reaction rates, dosimetry cross sections, and prior spectrum covariance matrix. All of these parameters were found to be very important in the spectrum adjustment. The most significant deficiency in the nuclear data is the absence of a good prior covariance matrix. Covariance matrices generated from analytic models of the fission spectra have been used in the past. This analysis reveals some unusual features in the covariance matrix produced with this approach. Specific needs are identified for improved nuclear data to better determine the 235 U spectrum. An improved 235 U covariance matrix and adjusted spectrum are recommended for use in radiation transport sensitivity analyses

Generation of a scale-invariant spectrum of adiabatic fluctuations in cosmological models with a contracting phase

International Nuclear Information System (INIS)

Finelli, Fabio; Brandenberger, Robert

2002-01-01

In pre-big-bang and in ekpyrotic cosmology, perturbations on cosmological scales today are generated from quantum vacuum fluctuations during a phase when the Universe is contracting (viewed in the Einstein frame). The backgrounds studied to date do not yield a scale-invariant spectrum of adiabatic fluctuations. Here, we present a new contracting background model (neither of pre-big-bang nor of the ekpyrotic form) involving a single scalar field coupled to gravity in which a scale-invariant spectrum of curvature fluctuations and gravitational waves results. The equation of state of this scalar field corresponds to cold matter. We demonstrate that if this contracting phase can be matched via a nonsingular bounce to an expanding Friedmann cosmology, the scale-invariance of the curvature fluctuations is maintained. We also find new background solutions for pre-big-bang and for ekpyrotic cosmology, which involve two scalar fields with exponential potentials with background values which are evolving in time. We comment on the difficulty of obtaining a scale-invariant spectrum of adiabatic fluctuations with background solutions which have been studied in the past

An empirical line-by-line model for the infrared solar transmittance spectrum from 700 to 5000cm{sup -1}

Energy Technology Data Exchange (ETDEWEB)

Hase, F. [Institut fuer Meteorologie und Klimaforschung, Forschungszentrum Karlsruhe, Postfach 3640, D-76021 Karlsruhe (Germany)]. E-mail: frank.hase@imk.fzk.de; Demoulin, P. [Institut d' Astrophysique et de Geophysique, allee du VI aout, 17, batiment B5a, B-4000, Liege (Belgium); Sauval, A.J. [Observatoire Royal de Belgique, avenue circulaire, 3, B-1180, Bruxelles (Belgium); Toon, G.C. [Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Bernath, P.F. [Department of Chemistry, University of Waterloo, Waterloo, Ont., Canada N2L3G1 (Canada); Goldman, A. [Department of Physics, University of Denver, Denver, CO 80208 (United States); Hannigan, J.W. [Atmospheric Chemistry Division, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80303 (United States); Rinsland, C.P. [NASA Langley Research Center, Hampton, VA 23681-2199 (United States)

2006-12-15

An empirical line-by-line model for the infrared solar transmittance spectrum is presented. The model can be incorporated into radiative transfer codes to allow fast calculation of all relevant emission and absorption features in the solar spectrum in the mid-infrared region from 700 to 5000cm{sup -1}. The transmittance is modelled as a function of the diameter of the field-of-view centered on the solar disk: the line broadening due to solar rotation as well as center-to-limb variations in strength and width are taken into account for stronger lines. Applications of the model presented here are in the fields of terrestrial remote sensing in the mid-infrared spectral region when the sun is used as radiation source or scattered solar radiation contributes to the measured signal and in the fields of atmospheric radiative transfer algorithms which compute the propagation of infrared solar radiation in the terrestrial atmosphere.

Endophytic synthesis of silver chloride nanoparticles from Penicillium sp. of Calophyllum apetalum

Science.gov (United States)

Chandrappa, C. P.; Govindappa, M.; Chandrasekar, N.; Sarkar, Sonia; Ooha, Sepuri; Channabasava, R.

2016-06-01

In the present study, Penicillium species extract isolated from Calophyllum apetalum was used for the synthesis of silver nanoparticles and it was confirmed by changing the color of the silver nitrate UV-Vis spectrum. The synthesized nanoparticles have been characterized by biophysical techniques such as scanning electron microscopy and x-ray diffraction.

Spectrum and H(10) of secondary neutrons around Linacs

International Nuclear Information System (INIS)

Ortiz H, A.; Hernandez A, B.; Vega C, H. R.; Hernandez D, V. M.; Rivera M, T.

2009-10-01

Neutron spectrum and ambient dose equivalent has been measured around two 10 MV linear accelerators. Accelerators are Siemens, one is a Mevatron model while another is the Primus. Main differences between those models are the beam collimator and the vault room. Here, Bonner sphere spectrometer with a passive thermal neutron detector has been utilized to measure the neutron spectrum inside the vault. Using an active detector the neutron spectrum was measured by the vaults door of both accelerators. With a neutron area monitor the dose equivalent was measured by the doors. Neutron strength, total fluence rate and ambient dose equivalent were compared, from this was found that shielding conditions are better in the Primus model. (Author)

On a multistable competitive network model in the case of an inhomogeneous growth rate spectrum: With an application to priming

International Nuclear Information System (INIS)

Frank, T.D.

2009-01-01

A stability analysis of a network model proposed by Haken is carried out for the case of an inhomogeneous spectrum of growth rates. The degree of multistability as a function of the coupling strength between network units is determined. An application to priming shows that the network can reconstruct the fundamental phenomenon that primed items have shorter recall latencies than non-primed items when assuming that learning affects the inhomogeneity of the growth rate spectrum.

Comprehensive ecosystem model-data synthesis using multiple data sets at two temperate forest free-air CO2 enrichment experiments: Model performance at ambient CO2 concentration

Science.gov (United States)

Walker, Anthony P.; Hanson, Paul J.; De Kauwe, Martin G.; Medlyn, Belinda E.; Zaehle, Sönke; Asao, Shinichi; Dietze, Michael; Hickler, Thomas; Huntingford, Chris; Iversen, Colleen M.; Jain, Atul; Lomas, Mark; Luo, Yiqi; McCarthy, Heather; Parton, William J.; Prentice, I. Colin; Thornton, Peter E.; Wang, Shusen; Wang, Ying-Ping; Warlind, David; Weng, Ensheng; Warren, Jeffrey M.; Woodward, F. Ian; Oren, Ram; Norby, Richard J.

2014-05-01

Free-air CO2 enrichment (FACE) experiments provide a remarkable wealth of data which can be used to evaluate and improve terrestrial ecosystem models (TEMs). In the FACE model-data synthesis project, 11 TEMs were applied to two decadelong FACE experiments in temperate forests of the southeastern U.S.—the evergreen Duke Forest and the deciduous Oak Ridge Forest. In this baseline paper, we demonstrate our approach to model-data synthesis by evaluating the models' ability to reproduce observed net primary productivity (NPP), transpiration, and leaf area index (LAI) in ambient CO2 treatments. Model outputs were compared against observations using a range of goodness-of-fit statistics. Many models simulated annual NPP and transpiration within observed uncertainty. We demonstrate, however, that high goodness-of-fit values do not necessarily indicate a successful model, because simulation accuracy may be achieved through compensating biases in component variables. For example, transpiration accuracy was sometimes achieved with compensating biases in leaf area index and transpiration per unit leaf area. Our approach to model-data synthesis therefore goes beyond goodness-of-fit to investigate the success of alternative representations of component processes. Here we demonstrate this approach by comparing competing model hypotheses determining peak LAI. Of three alternative hypotheses—(1) optimization to maximize carbon export, (2) increasing specific leaf area with canopy depth, and (3) the pipe model—the pipe model produced peak LAI closest to the observations. This example illustrates how data sets from intensive field experiments such as FACE can be used to reduce model uncertainty despite compensating biases by evaluating individual model assumptions.

Predicting speech intelligibility in adverse conditions: evaluation of the speech-based envelope power spectrum model

DEFF Research Database (Denmark)

Jørgensen, Søren; Dau, Torsten

2011-01-01

conditions by comparing predictions to measured data from [Kjems et al. (2009). J. Acoust. Soc. Am. 126 (3), 1415-1426] where speech is mixed with four different interferers, including speech-shaped noise, bottle noise, car noise, and cafe noise. The model accounts well for the differences in intelligibility......The speech-based envelope power spectrum model (sEPSM) [Jørgensen and Dau (2011). J. Acoust. Soc. Am., 130 (3), 1475–1487] estimates the envelope signal-to-noise ratio (SNRenv) of distorted speech and accurately describes the speech recognition thresholds (SRT) for normal-hearing listeners...... observed for the different interferers. None of the standardized models successfully describe these data....

Study of the environmental neutron spectrum at Zacatecas city

International Nuclear Information System (INIS)

Vega C, H.R.

2003-01-01

The environmental neutron spectrum has been measured at Zacatecas City in Mexico. Neutron spectrum was unfolded from count rates obtained with a multisphere neutron spectrometer with a Li I(Eu) scintillator. With the spectrum information the ambient dose equivalent and the isotropic effective dose were calculated. A model based upon the geomagnetic latitude and the altitude above sea level, that allows to estimate the neutron fluence rate is proposed, the model results are compared with total neutron fluences measured at several locations worldwide. Environmental neutron spectrum shows peaks at 1 and 100 MeV as well as a relevant amount of low energy neutrons. The neutron fluence rate was 65 ± 3 cm -2 -h -1 , producing 13.7 ± 0.6 n Sv-h -1 due to ambient dose equivalent rate and an isotropic effective dose rate of 14.1 ± 0.6 n Sv-h -1 . Neutron fluence rates predicted with the model are in agreement with those reported in the literature. (Author)

Study of the environmental neutron spectrum at Zacatecas city

Energy Technology Data Exchange (ETDEWEB)

Vega C, H.R. [Universidad Autonoma de Zacatecas, Cuerpo Academico de Radiobiologia, A.P. 336, 98000 Zacatecas (Mexico)

2003-07-01

The environmental neutron spectrum has been measured at Zacatecas City in Mexico. Neutron spectrum was unfolded from count rates obtained with a multisphere neutron spectrometer with a Li I(Eu) scintillator. With the spectrum information the ambient dose equivalent and the isotropic effective dose were calculated. A model based upon the geomagnetic latitude and the altitude above sea level, that allows to estimate the neutron fluence rate is proposed, the model results are compared with total neutron fluences measured at several locations worldwide. Environmental neutron spectrum shows peaks at 1 and 100 MeV as well as a relevant amount of low energy neutrons. The neutron fluence rate was 65 {+-} 3 cm{sup -2}-h{sup -1}, producing 13.7 {+-} 0.6 n Sv-h{sup -1} due to ambient dose equivalent rate and an isotropic effective dose rate of 14.1 {+-} 0.6 n Sv-h{sup -1}. Neutron fluence rates predicted with the model are in agreement with those reported in the literature. (Author)

Pharmaceutical supply chain models: A synthesis from a systems view of operations research

Directory of Open Access Journals (Sweden)

Ettore Settanni

Full Text Available This research evaluates reconfiguration opportunities in Pharmaceutical Supply Chains (PSC resulting from technology interventions in manufacturing, and new, more patient-centric delivery models. A critical synthesis of the academic and practice literature is used to identify, conceptualise, analyse and categorise PSC models. From a theoretical perspective, a systems view of operations research is adopted to provide insights on a broader range of OR activities, from conceptual to mathematical modelling and model solving, up to implementation.The research demonstrates that: 1 current definitions of the PSC are largely production-centric and fail to capture patient consumption, and hence healthcare outcomes; 2 most PSC mathematical models lack adequate conceptualisation of the structure and behaviour of the supply chain, and the boundary conditions that need to be considered for a given problem; 3 models do not adequately specify current unit operations or future production technology options, and are therefore unable to address the critical questions around alternative product or process technologies; 4 economic evaluations are limited to direct costing, rather than systemic approaches such as supply chain costing and total cost of ownership.While current models of the PSC may help with the optimisation of specific unit operations, their theoretical benefits could be offset by the dynamics of complex upstream (supply and downstream (distribution and healthcare delivery systems. To overcome these limitations, this research provides initial directions towards an integrated systems approach to PSC modelling. This perspective involves problem conceptualisation and boundary definition; design, formulation and solution of mathematical models, through to practical implementation of identified solutions. For both academics and practitioners, research findings suggest a systems approach to PSC modelling can provide improved conceptualisation and

Selecting the optimal synthesis parameters of InP/CdxZn1-xSe quantum dots for a hybrid remote phosphor white LED for general lighting applications.

Science.gov (United States)

Ryckaert, Jana; Correia, António; Tessier, Mickael D; Dupont, Dorian; Hens, Zeger; Hanselaer, Peter; Meuret, Youri

2017-11-27

Quantum dots can be used in white LEDs for lighting applications to fill the spectral gaps in the combined emission spectrum of the blue pumping LED and a broad band phosphor, in order to improve the source color rendering properties. Because quantum dots are low scattering materials, their use can also reduce the amount of backscattered light which can increase the overall efficiency of the white LED. The absorption spectrum and narrow emission spectrum of quantum dots can be easily tuned by altering their synthesis parameters. Due to the re-absorption events between the different luminescent materials and the light interaction with the LED package, determining the optimal quantum dot properties is a highly non-trivial task. In this paper we propose a methodology to select the optimal quantum dot to be combined with a broad band phosphor in order to realize a white LED with optimal luminous efficacy and CRI. The methodology is based on accurate and efficient simulations using the extended adding-doubling approach that take into account all the optical interactions. The method is elaborated for the specific case of a hybrid, remote phosphor white LED with YAG:Ce phosphor in combination with InP/CdxZn 1-x Se type quantum dots. The absorption and emission spectrum of the quantum dots are generated in function of three synthesis parameters (core size, shell size and cadmium fraction) by a semi-empirical 'quantum dot model' to include the continuous tunability of these spectra. The sufficiently fast simulations allow to scan the full parameter space consisting of these synthesis parameters and luminescent material concentrations in terms of CRI and efficacy. A conclusive visualization of the final performance allows to make a well-considered trade-off between these performance parameters. For the hybrid white remote phosphor LED with YAG:Ce and InP/CdxZn 1-x Se quantum dots a CRI Ra = 90 (with R9>50) and an overall efficacy of 110 lm/W is found.

Kaon-pion ratio from ISR results and the derived sea level muon spectrum from Maeda's model

CERN Document Server

Bhattacharya, D P

1978-01-01

The sea-level muon spectrum has been calculated using Maeda's (1973) model. The contribution of the muon flux caused by kaon decay has been included in the calculation as the kaon-pion ratio. The value used for this ratio is that determined by the CERN Intersecting Storage Ring Group, Antinucci et al. (1973). (7 refs).

Analysis and synthesis of laughter

Science.gov (United States)

Sundaram, Shiva; Narayanan, Shrikanth

2004-10-01

There is much enthusiasm in the text-to-speech community for synthesis of emotional and natural speech. One idea being proposed is to include emotion dependent paralinguistic cues during synthesis to convey emotions effectively. This requires modeling and synthesis techniques of various cues for different emotions. Motivated by this, a technique to synthesize human laughter is proposed. Laughter is a complex mechanism of expression and has high variability in terms of types and usage in human-human communication. People have their own characteristic way of laughing. Laughter can be seen as a controlled/uncontrolled physiological process of a person resulting from an initial excitation in context. A parametric model based on damped simple harmonic motion to effectively capture these diversities and also maintain the individuals characteristics is developed here. Limited laughter/speech data from actual humans and synthesis ease are the constraints imposed on the accuracy of the model. Analysis techniques are also developed to determine the parameters of the model for a given individual or laughter type. Finally, the effectiveness of the model to capture the individual characteristics and naturalness compared to real human laughter has been analyzed. Through this the factors involved in individual human laughter and their importance can be better understood.

Testing the hadronic spectrum in the strange sector

International Nuclear Information System (INIS)

Parotto, P.

2017-01-01

Heavier resonances are continually being added to the hadronic spectrum from the Particle Data Group that follow an exponentially increasing mass spectrum. However, it has been suggested that even further states predicted from Quark Models are needed in the hadronic spectrum in order to improve the agreement between the hadron resonance gas model predictions and lattice QCD data. We find that the inclusion of such states with extrapolated branching ratios slightly decreases the freezeout temperature. To eliminate ambiguities, we introduce a first principle method to extract the freeze-out temperature for charged kaons from experimental data, which yields a lower bound of T fo ≳ 145 MeV for the highest collision energy at RHIC. (paper)

Absorption tuning of the green fluorescent protein chromophore: synthesis and studies of model compounds

DEFF Research Database (Denmark)

Brøndsted Nielsen, Mogens; Andersen, Lars Henrik; Rinza, Tomás Rocha

2011-01-01

The green fluorescent protein (GFP) chromophore is a heterocyclic compound containing a p-hydroxybenzylidine attached to an imidazol-5(4H)-one ring. This review covers the synthesis of a variety of model systems for elucidating the intrinsic optical properties of the chromophore in the gas phase ...

The Neutron Spectrum in a Uranium Tube

International Nuclear Information System (INIS)

Johansson, E.; Jonsson, E.; Lindberg, M.; Mednis, J.

1963-10-01

A series of experimental and theoretical investigations on neutron spectra in lattice cells has been started at the reactor R1. This report gives the results from the first one of these cells - one with a tube of natural -uranium surrounded by heavy water. In the measurements the cell was placed in the central, vertical channel of the reactor. The neutron spectrum from a lead scatterer in the uranium tube - outer diameter 49.2 mm, inner diameter 28.3 mm - was measured with a fast chopper in the energy region 0.01 to 100 eV. Subsidiary measurements indicated that the spectrum in the beam from the lead piece corresponds to the spectrum of the angular flux integrated over all angles. This correspondence is important for the interpretation of the experimental data. The thermal part of the spectrum was found to deviate significantly from a Maxwellian. However, the deviation is not very large, and one could use a Maxwellian, at least to give a rough idea of the hardness of the spectrum. For the present tube the temperature of this Maxwellian was estimated as 90 to 100 deg C above the moderator temperature (33 deg C). In the joining region the rise of the spectrum towards the thermal part is slower than for the cell boundary spectrum, measured earlier. In the epithermal region the limited resolution of the chopper has affected the measurements at the energies of the uranium resonances. However, the shape of the spectrum on the flanks of the first resonance in 238 U (6.68 eV) has been obtained accurately. In the theoretical treatment the THERMOS code with a free gas scattering model has been used. The energy region was 3.06 - 0.00025 eV. The agreement with the measurements is good for the thermal part - possibly the theoretical spectrum is a little softer than the experimental one. In the joining region the results from THERMOS are comparatively high - probably due to the scattering model used

The Neutron Spectrum in a Uranium Tube

Energy Technology Data Exchange (ETDEWEB)

Johansson, E; Jonsson, E; Lindberg, M; Mednis, J

1963-10-15

A series of experimental and theoretical investigations on neutron spectra in lattice cells has been started at the reactor R1. This report gives the results from the first one of these cells - one with a tube of natural -uranium surrounded by heavy water. In the measurements the cell was placed in the central, vertical channel of the reactor. The neutron spectrum from a lead scatterer in the uranium tube - outer diameter 49.2 mm, inner diameter 28.3 mm - was measured with a fast chopper in the energy region 0.01 to 100 eV. Subsidiary measurements indicated that the spectrum in the beam from the lead piece corresponds to the spectrum of the angular flux integrated over all angles. This correspondence is important for the interpretation of the experimental data. The thermal part of the spectrum was found to deviate significantly from a Maxwellian. However, the deviation is not very large, and one could use a Maxwellian, at least to give a rough idea of the hardness of the spectrum. For the present tube the temperature of this Maxwellian was estimated as 90 to 100 deg C above the moderator temperature (33 deg C). In the joining region the rise of the spectrum towards the thermal part is slower than for the cell boundary spectrum, measured earlier. In the epithermal region the limited resolution of the chopper has affected the measurements at the energies of the uranium resonances. However, the shape of the spectrum on the flanks of the first resonance in {sup 238}U (6.68 eV) has been obtained accurately. In the theoretical treatment the THERMOS code with a free gas scattering model has been used. The energy region was 3.06 - 0.00025 eV. The agreement with the measurements is good for the thermal part - possibly the theoretical spectrum is a little softer than the experimental one. In the joining region the results from THERMOS are comparatively high - probably due to the scattering model used.

Enhancing conflict negotiation strategies of adolescents with autism spectrum disorder using video modeling.

Science.gov (United States)

Hochhauser, M; Weiss, P L; Gal, E

2018-01-01

Adolescents with autism spectrum disorder (ASD) have particular difficulty in negotiating conflict. A randomized control trial (RCT) was carried out to determine whether the negotiation strategies of adolescents with ASD would be enhanced via a 6-week intervention based on a video modeling application. Adolescents with ASD, aged 12-18 years, were randomly divided into an intervention group (n = 36) and a non-treatment control group (n = 25). Participants' negotiating strategies prior to and following the intervention were measured using the Five Factor Negotiation Scale (FFNS; Nakkula & Nikitopoulos, 1999) and the ConflicTalk questionnaire (Kimsey & Fuller, 2003). The results suggest that video modeling is an effective intervention for improving and maintaining conflict negotiation strategies of adolescents with ASD.

Template-Assisted Synthesis and Characterization of Passivated Nickel Nanoparticles

Directory of Open Access Journals (Sweden)

Al-Omari IA

2010-01-01

Full Text Available Abstract Potential applications of nickel nanoparticles demand the synthesis of self-protected nickel nanoparticles by different synthesis techniques. A novel and simple technique for the synthesis of self-protected nickel nanoparticles is realized by the inter-matrix synthesis of nickel nanoparticles by cation exchange reduction in two types of resins. Two different polymer templates namely strongly acidic cation exchange resins and weakly acidic cation exchange resins provided with cation exchange sites which can anchor metal cations by the ion exchange process are used. The nickel ions which are held at the cation exchange sites by ion fixation can be subsequently reduced to metal nanoparticles by using sodium borohydride as the reducing agent. The composites are cycled repeating the loading reduction cycle involved in the synthesis procedure. X-Ray Diffraction, Scanning Electron Microscopy, Transmission Electron microscopy, Energy Dispersive Spectrum, and Inductively Coupled Plasma Analysis are effectively utilized to investigate the different structural characteristics of the nanocomposites. The hysteresis loop parameters namely saturation magnetization and coercivity are measured using Vibrating Sample Magnetometer. The thermomagnetization study is also conducted to evaluate the Curie temperature values of the composites. The effect of cycling on the structural and magnetic characteristics of the two composites are dealt in detail. A comparison between the different characteristics of the two nanocomposites is also provided.

PROBING THE INFLATON: SMALL-SCALE POWER SPECTRUM CONSTRAINTS FROM MEASUREMENTS OF THE COSMIC MICROWAVE BACKGROUND ENERGY SPECTRUM

International Nuclear Information System (INIS)

Chluba, Jens; Erickcek, Adrienne L.; Ben-Dayan, Ido

2012-01-01

In the early universe, energy stored in small-scale density perturbations is quickly dissipated by Silk damping, a process that inevitably generates μ- and y-type spectral distortions of the cosmic microwave background (CMB). These spectral distortions depend on the shape and amplitude of the primordial power spectrum at wavenumbers k ∼ 4 Mpc –1 . Here, we study constraints on the primordial power spectrum derived from COBE/FIRAS and forecasted for PIXIE. We show that measurements of μ and y impose strong bounds on the integrated small-scale power, and we demonstrate how to compute these constraints using k-space window functions that account for the effects of thermalization and dissipation physics. We show that COBE/FIRAS places a robust upper limit on the amplitude of the small-scale power spectrum. This limit is about three orders of magnitude stronger than the one derived from primordial black holes in the same scale range. Furthermore, this limit could be improved by another three orders of magnitude with PIXIE, potentially opening up a new window to early universe physics. To illustrate the power of these constraints, we consider several generic models for the small-scale power spectrum predicted by different inflation scenarios, including running-mass inflation models and inflation scenarios with episodes of particle production. PIXIE could place very tight constraints on these scenarios, potentially even ruling out running-mass inflation models if no distortion is detected. We also show that inflation models with sub-Planckian field excursion that generate detectable tensor perturbations should simultaneously produce a large CMB spectral distortion, a link that could potentially be established with PIXIE.

Video Modeling for Teaching Daily Living Skills to Children with Autism Spectrum Disorder: A Pilot Study

Science.gov (United States)

Meister, Christine; Salls, Joyce

2015-01-01

This pilot study investigated the efficacy of point-of-view video modeling as an intervention strategy to improve self-help skills in children with autism spectrum disorder (ASD). A single-subject A-B design was implemented with eight school-aged children ages 7.5 years to 13.5 years. Six of the students participated in general education classes…

Two-zone model for the broadband Crab nebula spectrum: microscopic interpretation

Directory of Open Access Journals (Sweden)

Fraschetti F.

2017-01-01

Full Text Available We develop a simple two-zone interpretation of the broadband baseline Crab nebula spectrum between 10−5 eV and ~ 100 TeV by using two distinct log-parabola energetic electrons distributions. We determine analytically the very-high energy photon spectrum as originated by inverse-Compton scattering of the far-infrared soft ambient photons within the nebula off a first population of electrons energized at the nebula termination shock. The broad and flat 200 GeV peak jointly observed by Fermi/LAT and MAGIC is naturally reproduced. The synchrotron radiation from a second energetic electron population explains the spectrum from the radio range up to ~ 10 keV. We infer from observations the energy dependence of the microscopic probability of remaining in proximity of the shock of the accelerating electrons.

Band electron spectrum and thermodynamic properties of the pseudospin-electron model with tunneling splitting of levels

Directory of Open Access Journals (Sweden)

O.Ya.Farenyuk

2006-01-01

Full Text Available The pseudospin-electron model with tunneling splitting of levels is considered. Generalization of dynamic mean-field method for systems with correlated hopping was applied to the investigation of the model. Electron spectra, electron concentrations, average values of pseudospins and grand canonical potential were calculated within the alloy-analogy approximation. Electron spectrum and dependencies of the electron concentrations on chemical potential were obtained. It was shown that in the alloy-analogy approximation, the model possesses the first order phase transition to ferromagnetic state with the change of chemical potential and the second order phase transition with the change of temperature.

The Lived Experience of US Parents of Children with Autism Spectrum Disorders: A Systemic Review and Meta-Synthesis

Science.gov (United States)

Corcoran, Jacqueline; Berry, Amber; Hill, Stephanie

2015-01-01

Current US statistics indicate that 1 in 68 children is diagnosed with an autistic spectrum disorder (Centers for Disease Control (2014) Prevalence of autism spectrum disorder among children aged 8 years--autism and developmental disabilities monitoring network, 11 Sites, United States, 2010. "Morbidity and Mortality Weekly Report"…

Modeling methodology for supply chain synthesis and disruption analysis

Science.gov (United States)

Wu, Teresa; Blackhurst, Jennifer

2004-11-01

The concept of an integrated or synthesized supply chain is a strategy for managing today's globalized and customer driven supply chains in order to better meet customer demands. Synthesizing individual entities into an integrated supply chain can be a challenging task due to a variety of factors including conflicting objectives, mismatched incentives and constraints of the individual entities. Furthermore, understanding the effects of disruptions occurring at any point in the system is difficult when working toward synthesizing supply chain operations. Therefore, the goal of this research is to present a modeling methodology to manage the synthesis of a supply chain by linking hierarchical levels of the system and to model and analyze disruptions in the integrated supply chain. The contribution of this research is threefold: (1) supply chain systems can be modeled hierarchically (2) the performance of synthesized supply chain system can be evaluated quantitatively (3) reachability analysis is used to evaluate the system performance and verify whether a specific state is reachable, allowing the user to understand the extent of effects of a disruption.

DEVELOPMENT OF A COMPUTATIONAL MULTIPHASE FLOW MODEL FOR FISCHER TROPSCH SYNTHESIS IN A SLURRY BUBBLE COLUMN REACTOR

Energy Technology Data Exchange (ETDEWEB)

Donna Post Guillen; Tami Grimmett; Anastasia M. Gribik; Steven P. Antal

2010-09-01

The Hybrid Energy Systems Testing (HYTEST) Laboratory is being established at the Idaho National Laboratory to develop and test hybrid energy systems with the principal objective to safeguard U.S. Energy Security by reducing dependence on foreign petroleum. A central component of the HYTEST is the slurry bubble column reactor (SBCR) in which the gas-to-liquid reactions will be performed to synthesize transportation fuels using the Fischer Tropsch (FT) process. SBCRs are cylindrical vessels in which gaseous reactants (for example, synthesis gas or syngas) is sparged into a slurry of liquid reaction products and finely dispersed catalyst particles. The catalyst particles are suspended in the slurry by the rising gas bubbles and serve to promote the chemical reaction that converts syngas to a spectrum of longer chain hydrocarbon products, which can be upgraded to gasoline, diesel or jet fuel. These SBCRs operate in the churn-turbulent flow regime which is characterized by complex hydrodynamics, coupled with reacting flow chemistry and heat transfer, that effect reactor performance. The purpose of this work is to develop a computational multiphase fluid dynamic (CMFD) model to aid in understanding the physico-chemical processes occurring in the SBCR. Our team is developing a robust methodology to couple reaction kinetics and mass transfer into a four-field model (consisting of the bulk liquid, small bubbles, large bubbles and solid catalyst particles) that includes twelve species: (1) CO reactant, (2) H2 reactant, (3) hydrocarbon product, and (4) H2O product in small bubbles, large bubbles, and the bulk fluid. Properties of the hydrocarbon product were specified by vapor liquid equilibrium calculations. The absorption and kinetic models, specifically changes in species concentrations, have been incorporated into the mass continuity equation. The reaction rate is determined based on the macrokinetic model for a cobalt catalyst developed by Yates and Satterfield [1]. The

Synthesis of carbon nanomaterials from different pyrolysis techniques: a review

Science.gov (United States)

Umer Zahid, Muhammad; Pervaiz, Erum; Hussain, Arshad; Shahzad, Muhammad Imran; Niazi, Muhammad Bilal Khan

2018-05-01

In the current age, the significance of carbon-based nanomaterials for many applications has made the efforts for the facile synthesis methods from abundantly available wastes in a cost-effective way. Pyrolysis in a broad spectrum is commonly employed for the synthesis of carbon nanostructures by thermally treating the organic waste. The mechanism of growth of the nanoparticles determines the functional distribution of nanoparticles based on the growing size, medium, and physio-chemical properties. Carbon nanomaterial’s growth is a complicated process which is profoundly influenced by temperature, catalyst, and type of precursor. Nowadays, significant progress has been made in improving nanomaterial’s growth techniques, opening new paths for commercial production of carbon-based nanomaterials. The most promising are the methods involving hydrocarbon-rich organic waste as the feed source. In this review, synthesis of carbon-based nanomaterials, specifically carbon nanotubes (CNTs), Carbon nanofibers (CNFs) and Graphene (G) are discussed by different pyrolysis techniques. Furthermore, the review explores recent advancements made in the context of pyrolysis.

Nonlinear evolution of f(R) cosmologies. II. Power spectrum

International Nuclear Information System (INIS)

Oyaizu, Hiroaki; Hu, Wayne; Lima, Marcos

2008-01-01

We carry out a suite of cosmological simulations of modified action f(R) models where cosmic acceleration arises from an alteration of gravity instead of dark energy. These models introduce an extra scalar degree of freedom which enhances the force of gravity below the inverse mass or Compton scale of the scalar. The simulations exhibit the so-called chameleon mechanism, necessary for satisfying local constraints on gravity, where this scale depends on environment, in particular, the depth of the local gravitational potential. We find that the chameleon mechanism can substantially suppress the enhancement of power spectrum in the nonlinear regime if the background field value is comparable to or smaller than the depth of the gravitational potentials of typical structures. Nonetheless power spectrum enhancements at intermediate scales remain at a measurable level for models even when the expansion history is indistinguishable from a cosmological constant, cold dark matter model. Simple scaling relations that take the linear power spectrum into a nonlinear spectrum fail to capture the modifications of f(R) due to the change in collapsed structures, the chameleon mechanism, and the time evolution of the modifications.

Adult Autism Subthreshold Spectrum (AdAS Spectrum): Validation of a questionnaire investigating subthreshold autism spectrum.

Science.gov (United States)

Dell'Osso, L; Gesi, C; Massimetti, E; Cremone, I M; Barbuti, M; Maccariello, G; Moroni, I; Barlati, S; Castellini, G; Luciano, M; Bossini, L; Rocchetti, M; Signorelli, M; Aguglia, E; Fagiolini, A; Politi, P; Ricca, V; Vita, A; Carmassi, C; Maj, M

2017-02-01

Increasing literature has shown the usefulness of a dimensional approach to autism. The present study aimed to determine the psychometric properties of the Adult Autism Subthreshold Spectrum (AdAS Spectrum), a new questionnaire specifically tailored to assess subthreshold forms of autism spectrum disorder (ASD) in adulthood. 102 adults endorsing at least one DSM-5 symptom criterion for ASD (ASDc), 143 adults diagnosed with a feeding and eating disorder (FED), and 160 subjects with no mental disorders (CTL), were recruited from 7 Italian University Departments of Psychiatry and administered the following: SCID-5, Autism-Spectrum Quotient (AQ), Ritvo Autism and Asperger Diagnostic Scale 14-item version (RAADS-14), and AdAS Spectrum. The AdAS Spectrum demonstrated excellent internal consistency for the total score (Kuder-Richardson's coefficient=.964) as well as for five out of seven domains (all coefficients>.80) and sound test-retest reliability (ICC=.976). The total and domain AdAS Spectrum scores showed a moderate to strong (>.50) positive correlation with one another and with the AQ and RAADS-14 total scores. ASDc subjects reported significantly higher AdAS Spectrum total scores than both FED (pcriteria (FED 0 ) and those with one ASD symptom criterion (FED 1 ) , a gradient of severity in AdAS Spectrum scores from CTL subjects to ASD patients, across FED 0 , ASD 1 , FED 1 was shown. The AdAS Spectrum showed excellent internal consistency and test-retest reliability and strong convergent validity with alternative dimensional measures of ASD. The questionnaire performed differently among the three diagnostic groups and enlightened some significant effects of gender in the expression of autistic traits. Copyright © 2016 Elsevier Inc. All rights reserved.

Influence of synthesis energy on physical properties of the oxide nanoparticles

International Nuclear Information System (INIS)

Medeiros, A.A.S.; Mello, V.S. e; Trajano, M.F.; Alves, S.M.

2014-01-01

Nanoparticles are present in many research areas giving a range of applications, one of them is lubricant technology. Oxide nanoparticles have been used as extreme pressure additives in boundary lubrication with good results. The great challenge of this technology is in control of the nanoparticles dispersion to ensure their actions as anti-wear additive. This study goal was to evaluate the influence of the amount of energy synthesis in the dispersive properties, size and shape of nanoparticles synthesized by microwave, varying the amount of energy transferred during the synthesis process. The morphology of the nanoparticles was evaluated by SEM and XRD spectrum was used to identify the crystallite size and the formation of copper oxides. The results showed that the size and shape of the particle, and consequently the dispersion, are directly related to amount of energy used in the synthesis are directly related. (author)

Hγ Line Spectrum of Intermediate Polars

Directory of Open Access Journals (Sweden)

Yonggi Kim

1998-06-01

Full Text Available Kim & Beuermann (1995, 1996 have developed a model for the propagation of X-rays from the accreting white dwarf through the infalling material and the re-emission of the energy deposited by photo-absorption in the optical (and UV spectral range. By using this model, we calculate the profiles of the Hγ emission-line spectrum of intermediate polars. Photoabsorption of X-rays by the infalling material is the dominant process in forming the observed energy-dependent rotational modulation of the X-ray flux. X-ray and optical modulations are sensitive to model parameters in different ways. In principle, these dependencies allow us to obtain improved insight into the accretion geometry of the intermediate polars. We present results of our calculations and compare them with the Hβ line spectrum (Kim & Beuermann 1996.

Evaluation of substitution monopole models for tire noise sound synthesis

Science.gov (United States)

Berckmans, D.; Kindt, P.; Sas, P.; Desmet, W.

2010-01-01

Due to the considerable efforts in engine noise reduction, tire noise has become one of the major sources of passenger car noise nowadays and the demand for accurate prediction models is high. A rolling tire is therefore experimentally characterized by means of the substitution monopole technique, suiting a general sound synthesis approach with a focus on perceived sound quality. The running tire is substituted by a monopole distribution covering the static tire. All monopoles have mutual phase relationships and a well-defined volume velocity distribution which is derived by means of the airborne source quantification technique; i.e. by combining static transfer function measurements with operating indicator pressure measurements close to the rolling tire. Models with varying numbers/locations of monopoles are discussed and the application of different regularization techniques is evaluated.

Features in the primordial power spectrum of double D-term inflation

International Nuclear Information System (INIS)

Lesgourgues, Julien

2000-01-01

Recently, there has been some interest for building supersymmetric models of double inflation. These models, realistic from a particle physics point of view, predict a broken-scale-invariant power spectrum of primordial cosmological perturbations, that may explain eventual nontrivial features in the present matter power spectrum. In previous works, the primordial spectrum was calculated using analytic slow-roll approximations. However, these models involve a fast second-order phase transition during inflation, with a stage of spinodal instability, and an interruption of slow-roll. For our previous model of double D-term inflation, we simulate numerically the evolution of quantum fluctuations, taking into account the spinodal modes, and we show that the semiclassical approximation can be employed even during the transition, due to the presence of a second inflaton field. The primordial power spectrum possesses a rich structure, and possibly, a non-Gaussian spike on observable scales

Frequency-wavenumber spectrum for GATE phase I rainfields

Science.gov (United States)

Nakamoto, Shoichiro; Valdes, Juan B.; North, Gerald R.

1990-01-01

The oceanic rainfall frequency-wavenumber spectrum and its associated space-time correlation have been evaluated from subsets of GATE phase I data. The records, of a duration of four days, were sampled at 15 minutes intervals in 4 x 4 km grid boxes over a 400 km diameter hexagon. In the low frequencies-low wavenumber region the results coincide with those obtained by using the stochastic model proposed by North and Nakomoto (1989). From the derived spectrum the inherent time and space scales of the stochastic model were determined to be approximately 13 hours and 36 km. The formalism proposed by North and Nakamoto was taken together with the derived spectrum to compute the mean square sampling error due to intermittent visits of a spaceborne sensor.

The synthesis of a novel octapeptidolipid antibiotic

International Nuclear Information System (INIS)

Levitt, R.R.

1986-05-01

The bacillomycins comprise a group of antifungal polypeptide antibiotic compounds closely related in terms of their physico-chemical properties, amino acid and β-amino fatty acid compositions. Iturin A, which belongs to the bacillomycins, consists of seven amino acids. Attempts to produce a β-NC 15 fatty acid in acceptable yield proved unsuccessful and was later discarded in favour of the preparation of a β-NC 14 fatty acid. The different experimental procedures used and results obtained when preparing both fatty acids are detailed. The method developed in preparing the β-NC 14 fatty acid affords a new general synthetic route for the production of β-amino fatty acids in good yield. The strategy considered in selecting which amino acid to commence the peptide synthesis with, the use in the Merrifield procedure of N-protected amino acids, coupling reagents, deprotecting and cleaving agents, and the HPLC purification procedures used for the linear and cyclic octapeptides, are all described. The 1 H-NMR spectrum of the synthetic cyclic compound compared favourably with the spectrum of natural iturin A and these results are also presented. This dissertation presents the total synthesis of a novel octapeptidolipid antifungal antibiotic (iturin A analogue), utilising the Merrifield solid phase procedure. The biological activity of the synthesised and purified linear and cyclic iturin A analogues were compared with that of bacillomycin S. The test for biological activity and results obtained are described and illustrated with photographic plates

Spectrum of the extragalactic background light

Energy Technology Data Exchange (ETDEWEB)

Bruzual A, G [Centro de Investigacion de Astronomia, Merida (Venezuela)

1981-01-01

The observed spectrum of the extragalactic background light in the range from ultraviolet to optical wavelengths is compared with a model prediction. The model uses the locally observed luminosity function of galaxies as well as evolutionary models for galaxy spectral energy distributions. The predicition is too faint by a factor of about 10.

Unintended phosphorus doping of nickel nanoparticles during synthesis with TOP: a discovery through structural analysis.

Science.gov (United States)

Moreau, Liane M; Ha, Don-Hyung; Bealing, Clive R; Zhang, Haitao; Hennig, Richard G; Robinson, Richard D

2012-09-12

We report the discovery of unintentional phosphorus (P) doping when tri-n-octylphosphine (TOP) ligands are used in Ni nanoparticle synthesis, which is the most common method for monodisperse Ni nanoparticle synthesis. The nanoparticles appear pure face-centered cubic (fcc) Ni in X-ray diffraction despite the surprisingly high level (5 atomic %) of P. We find that the P doping follows a direct relationship with increased reaction time and temperature and that the P doping can be estimated with the degree of lattice expansion shown from a peak shift in the XRD spectrum. Through EXAFS modeling and density-functional (DFT) calculations of defect formation energies we find that the P atoms are preferentially located on the fcc lattice as substitutional dopants with oxidation state of zero. Magnetic and catalytic properties are shown to be greatly affected by this doping; DFT calculations show magnetization losses in the Ni system, as well as in Fe and Co systems. These findings are likely relevant for other metal syntheses that employ phosphine ligands.

Auralization of Accelerating Passenger Cars Using Spectral Modeling Synthesis

Directory of Open Access Journals (Sweden)

Reto Pieren

2015-12-01

Full Text Available While the technique of auralization has been in use for quite some time in architectural acoustics, the application to environmental noise has been discovered only recently. With road traffic noise being the dominant noise source in most countries, particular interest lies in the synthesis of realistic pass-by sounds. This article describes an auralizator for pass-bys of accelerating passenger cars. The key element is a synthesizer that simulates the acoustical emission of different vehicles, driving on different surfaces, under different operating conditions. Audio signals for the emitted tire noise, as well as the propulsion noise are generated using spectral modeling synthesis, which gives complete control of the signal characteristics. The sound of propulsion is synthesized as a function of instantaneous engine speed, engine load and emission angle, whereas the sound of tires is created in dependence of vehicle speed and emission angle. The sound propagation is simulated by applying a series of time-variant digital filters. To obtain the corresponding steering parameters of the synthesizer, controlled experiments were carried out. The tire noise parameters were determined from coast-by measurements of passenger cars with idling engines. To obtain the propulsion noise parameters, measurements at different engine speeds, engine loads and emission angles were performed using a chassis dynamometer. The article shows how, from the measured data, the synthesizer parameters are calculated using audio signal processing.

Data analysis of “krokodil” samples obtained by street-like synthesis

Directory of Open Access Journals (Sweden)

João Filipe Neves

2016-03-01

Full Text Available The data described in this work is related to be the subject of an article in the Forensic Science International, titled: “The harmful chemistry behind “krokodil”: street-like synthesis and product analysis” (http://dx.doi.org/10.1016/j.forsciint.2015.07.042 [1]. The data presented here provides additional description of the chemical profile of “krokodil”. Physicochemical and organoleptic characteristics, TLC profile, UV/Vis, 1H NMR and FTIR spectrum are presented. These data validate the proposed synthetic procedure and pathway and give further information about the contaminants present in “krokodil”. Keywords: “Krokodil”, Street like synthesis, TLC profile, UV/Vis, 1H NMR, FTIR

Synthesis, structure, theoretical studies and luminescent properties of a ternary erbium(III) complex with acetylacetone and bathophenanthroline ligands

Energy Technology Data Exchange (ETDEWEB)

Martín-Ramos, Pablo [CEMDRX, Department of Physics, Universidade de Coimbra, Rua Larga, P-3004-516 Coimbra (Portugal); Advanced Materials Laboratory, ETSIIAA, Universidad de Valladolid, Avenida de Madrid 44, 34004 Palencia (Spain); Silva, Pedro S. Pereira, E-mail: psidonio@pollux.fis.uc.pt [CEMDRX, Department of Physics, Universidade de Coimbra, Rua Larga, P-3004-516 Coimbra (Portugal); Chamorro-Posada, Pedro [Higher Technical School of Telecommunications Engineering, Universidad de Valladolid, Campus Miguel Delibes, Paseo Belén 15, 47011 Valladolid (Spain); Silva, Manuela Ramos [CEMDRX, Department of Physics, Universidade de Coimbra, Rua Larga, P-3004-516 Coimbra (Portugal); Milne, Bruce F. [Centre for Computational Physics, Department of Physics, Universidade de Coimbra, P-3004-516 Coimbra (Portugal); Donostia International Physics Centre, Paseo Manuel de Lardizabal 4, 20018 Donostia-San Sebastián (Spain); Nogueira, Fernando [Centre for Computational Physics, Department of Physics, Universidade de Coimbra, P-3004-516 Coimbra (Portugal); Martín-Gil, Jesús [Advanced Materials Laboratory, ETSIIAA, Universidad de Valladolid, Avenida de Madrid 44, 34004 Palencia (Spain)

2015-06-15

A novel erbium(III) complex with acetylacetone (Hacac) and bathophenanthroline (4,7-diphenyl-1,10-phenanthroline, bath) ligands, formulated as [Er(acac){sub 3}(bath)], has been characterized by elemental analysis, X-ray diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy, Raman spectroscopy, absorption and emission spectroscopies. In the theoretical part of this study, semi-empirical quantum chemistry methods using AM1, PM3, PM6 and PM7 models have been employed to predict the structure of the complex, calculate the geometric and crystallographic parameters, and make comparisons with spectroscopic data using INDO/S-CI calculations. Real-time time-dependent density-functional theory (TDDFT) has also been used to calculate the optical absorption spectrum of the complex in the gas phase. - Highlights: • Synthesis and structure of a new erbium(III) β-diketonate complex. • TDDFT used for the first time to calculate the optical absorption spectrum. • Complex show strong near-infrared luminescence at 1.53 µm due to antenna effect.

Synthesis, structure, theoretical studies and luminescent properties of a ternary erbium(III) complex with acetylacetone and bathophenanthroline ligands

International Nuclear Information System (INIS)

Martín-Ramos, Pablo; Silva, Pedro S. Pereira; Chamorro-Posada, Pedro; Silva, Manuela Ramos; Milne, Bruce F.; Nogueira, Fernando; Martín-Gil, Jesús

2015-01-01

A novel erbium(III) complex with acetylacetone (Hacac) and bathophenanthroline (4,7-diphenyl-1,10-phenanthroline, bath) ligands, formulated as [Er(acac) 3 (bath)], has been characterized by elemental analysis, X-ray diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy, Raman spectroscopy, absorption and emission spectroscopies. In the theoretical part of this study, semi-empirical quantum chemistry methods using AM1, PM3, PM6 and PM7 models have been employed to predict the structure of the complex, calculate the geometric and crystallographic parameters, and make comparisons with spectroscopic data using INDO/S-CI calculations. Real-time time-dependent density-functional theory (TDDFT) has also been used to calculate the optical absorption spectrum of the complex in the gas phase. - Highlights: • Synthesis and structure of a new erbium(III) β-diketonate complex. • TDDFT used for the first time to calculate the optical absorption spectrum. • Complex show strong near-infrared luminescence at 1.53 µm due to antenna effect

Clinical and Neurobiological Relevance of Current Animal Models of Autism Spectrum Disorders

Science.gov (United States)

Kim, Ki Chan; Gonzales, Edson Luck; Lázaro, María T.; Choi, Chang Soon; Bahn, Geon Ho; Yoo, Hee Jeong; Shin, Chan Young

2016-01-01

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by social and communication impairments, as well as repetitive and restrictive behaviors. The phenotypic heterogeneity of ASD has made it overwhelmingly difficult to determine the exact etiology and pathophysiology underlying the core symptoms, which are often accompanied by comorbidities such as hyperactivity, seizures, and sensorimotor abnormalities. To our benefit, the advent of animal models has allowed us to assess and test diverse risk factors of ASD, both genetic and environmental, and measure their contribution to the manifestation of autistic symptoms. At a broader scale, rodent models have helped consolidate molecular pathways and unify the neurophysiological mechanisms underlying each one of the various etiologies. This approach will potentially enable the stratification of ASD into clinical, molecular, and neurophenotypic subgroups, further proving their translational utility. It is henceforth paramount to establish a common ground of mechanistic theories from complementing results in preclinical research. In this review, we cluster the ASD animal models into lesion and genetic models and further classify them based on the corresponding environmental, epigenetic and genetic factors. Finally, we summarize the symptoms and neuropathological highlights for each model and make critical comparisons that elucidate their clinical and neurobiological relevance. PMID:27133257

Regulating the Emission Spectrum of CsPbBr3 from Green to Blue via Controlling the Temperature and Velocity of Microchannel Reactor

OpenAIRE

Yong Tang; Hanguang Lu; Longshi Rao; Zongtao Li; Xinrui Ding; Caiman Yan; Binhai Yu

2018-01-01

The ability to precisely obtain tunable spectrum of lead halide perovskite quantum dots (QDs) is very important for applications, such as in lighting and display. Herein, we report a microchannel reactor method for synthesis of CsPbBr3 QDs with tunable spectrum. By adjusting the temperature and velocity of the microchannel reactor, the emission peaks of CsPbBr3 QDs ranging from 520 nm to 430 nm were obtained, which is wider than that of QDs obtained in a traditional flask without changing hal...

Spectrum of perturbations arising in a nonsingular model of the Universe with the initial de Sitter stage and the anisotropy of the relic radiation

International Nuclear Information System (INIS)

Starobinskij, A.A.

1983-01-01

Spectrum of primary adiabatic perturbations and gravitational waves formed in the proposed earlier by the author nonsingular cosmological model with the initial quantum de Sitter stage generated by gravitational vacuum polarization is calculated. The spectrum of gravitational waves appears to be flat, the spectrum of adiabatic perturbations is close to the flat one. The large-scale anisotropy of the temperature T of the relic electromagnetic radiation due to these fluctuations is found. It is shown that the most promising way to detect the anisotropy in the case of a flat perturbation spectrum is the investigation of correlations of ΔT/T at the angles of 5 deg - 10 deg

Researches of fruit quality prediction model based on near infrared spectrum

Science.gov (United States)

Shen, Yulin; Li, Lian

2018-04-01

With the improvement in standards for food quality and safety, people pay more attention to the internal quality of fruits, therefore the measurement of fruit internal quality is increasingly imperative. In general, nondestructive soluble solid content (SSC) and total acid content (TAC) analysis of fruits is vital and effective for quality measurement in global fresh produce markets, so in this paper, we aim at establishing a novel fruit internal quality prediction model based on SSC and TAC for Near Infrared Spectrum. Firstly, the model of fruit quality prediction based on PCA + BP neural network, PCA + GRNN network, PCA + BP adaboost strong classifier, PCA + ELM and PCA + LS_SVM classifier are designed and implemented respectively; then, in the NSCT domain, the median filter and the SavitzkyGolay filter are used to preprocess the spectral signal, Kennard-Stone algorithm is used to automatically select the training samples and test samples; thirdly, we achieve the optimal models by comparing 15 kinds of prediction model based on the theory of multi-classifier competition mechanism, specifically, the non-parametric estimation is introduced to measure the effectiveness of proposed model, the reliability and variance of nonparametric estimation evaluation of each prediction model to evaluate the prediction result, while the estimated value and confidence interval regard as a reference, the experimental results demonstrate that this model can better achieve the optimal evaluation of the internal quality of fruit; finally, we employ cat swarm optimization to optimize two optimal models above obtained from nonparametric estimation, empirical testing indicates that the proposed method can provide more accurate and effective results than other forecasting methods.

Mental Health Interventions for Parent Carers of Children with Autistic Spectrum Disorder: Practice Guidelines from a Critical Interpretive Synthesis (CIS Systematic Review

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Denise Catalano

2018-02-01

Full Text Available Parent carers of children with Autism Spectrum Disorder (ASD often report increased levels of stress, depression, and anxiety. Unmet parent carer mental health needs pose a significant risk to the psychological, physical, and social well-being of the parents of the child affected by ASD and jeopardize the adaptive functioning of the family as well as the potential of the child affected by ASD. This systematic review identifies key qualities of interventions supporting the mental health of parent carers and proposes practitioner-parent carer support guidelines. A search of four databases (Medline, PubMed, PsycINFO, and Social Science Data was conducted to identify studies that met the following criteria: (1 an intervention was delivered to parent carers of a child with ASD under the age of 18 years; (2 the research design allowed for a comparison on outcomes across groups; and (3 outcome measures of the parent carers’ mental health were used. A total of 23 studies met the inclusion criteria. A critical interpretive synthesis approach was used to produce an integrated conceptualization of the evidence. Findings suggest practitioner guidelines to support the mental health and wellbeing of parent carers should include addressing the parent’s self-perspective taking and skill for real time problem-solving.

Mental Health Interventions for Parent Carers of Children with Autistic Spectrum Disorder: Practice Guidelines from a Critical Interpretive Synthesis (CIS) Systematic Review.

Science.gov (United States)

Catalano, Denise; Holloway, Linda; Mpofu, Elias

2018-02-14

Parent carers of children with Autism Spectrum Disorder (ASD) often report increased levels of stress, depression, and anxiety. Unmet parent carer mental health needs pose a significant risk to the psychological, physical, and social well-being of the parents of the child affected by ASD and jeopardize the adaptive functioning of the family as well as the potential of the child affected by ASD. This systematic review identifies key qualities of interventions supporting the mental health of parent carers and proposes practitioner-parent carer support guidelines. A search of four databases (Medline, PubMed, PsycINFO, and Social Science Data) was conducted to identify studies that met the following criteria: (1) an intervention was delivered to parent carers of a child with ASD under the age of 18 years; (2) the research design allowed for a comparison on outcomes across groups; and (3) outcome measures of the parent carers' mental health were used. A total of 23 studies met the inclusion criteria. A critical interpretive synthesis approach was used to produce an integrated conceptualization of the evidence. Findings suggest practitioner guidelines to support the mental health and wellbeing of parent carers should include addressing the parent's self-perspective taking and skill for real time problem-solving.

Interaction of a single mode field cavity with the 1D XY model: Energy spectrum

International Nuclear Information System (INIS)

Tonchev, H; Donkov, A A; Chamati, H

2016-01-01

In this work we use the fundamental in quantum optics Jaynes-Cummings model to study the response of spin 1/2chain to a single mode of a laser light falling on one of the spins, a focused interaction model between the light and the spin chain. For the spin-spin interaction along the chain we use the XY model. We report here the exact analytical results, obtained with the help of a computer algebra system, for the energy spectrum in this model for chains of up to 4 spins with nearest neighbors interactions, either for open or cyclic chain configurations. Varying the sign and magnitude of the spin exchange coupling relative to the light-spin interaction we have investigated both cases of ferromagnetic or antiferromagnetic spin chains. (paper)

Earth's transmission spectrum from lunar eclipse observations.

Science.gov (United States)

Pallé, Enric; Osorio, María Rosa Zapatero; Barrena, Rafael; Montañés-Rodríguez, Pilar; Martín, Eduardo L

2009-06-11

Of the 342 planets so far discovered orbiting other stars, 58 'transit' the stellar disk, meaning that they can be detected through a periodic decrease in the flux of starlight. The light from the star passes through the atmosphere of the planet, and in a few cases the basic atmospheric composition of the planet can be estimated. As we get closer to finding analogues of Earth, an important consideration for the characterization of extrasolar planetary atmospheres is what the transmission spectrum of our planet looks like. Here we report the optical and near-infrared transmission spectrum of the Earth, obtained during a lunar eclipse. Some biologically relevant atmospheric features that are weak in the reflection spectrum (such as ozone, molecular oxygen, water, carbon dioxide and methane) are much stronger in the transmission spectrum, and indeed stronger than predicted by modelling. We also find the 'fingerprints' of the Earth's ionosphere and of the major atmospheric constituent, molecular nitrogen (N(2)), which are missing in the reflection spectrum.

Nonlinear spectrum of the ablative Rayleigh-Taylor instability in laser-accelerated planar plasmas

International Nuclear Information System (INIS)

Keskinen, M. J.; Schmitt, A.

2007-01-01

A model for the nonlinear spectrum of the ablative Rayleigh-Taylor instability in laser-accelerated planar plasmas has been developed for a wide range of Froude numbers and scale sizes. It is found that the spectrum can be characterized by an inverse power law with spectral index of approximately 2 in the limit of small-wavenumber spectrum cutoffs and small-scale density gradient scale lengths. Comparison of the model spectrum with recent experimental observations is made with good agreement

Achievable capacity of a spectrum sharing system over hyper fading channels

KAUST Repository

Ekin, Sabit

2009-11-01

Cognitive radio with spectrum sharing feature is a promising technique to address the spectrum under-utilization problem in dynamically changing environments. In this paper, achievable capacity gain of spectrum sharing systems over dynamic fading environments is studied. For the analysis, a theoretical fading model called hyper fading model that is suitable to the dynamic nature of cognitive radio channel is proposed. Closed-form expression of probability density function (PDF) and cumulative density function (CDF) of the signal-to-noise ratio (SNR) for secondary users in spectrum sharing systems are derived. In addition, the capacity gains achievable with spectrum sharing systems in high and low power regions are obtained. Numerical simulations are performed to study the effects of different fading figures, average powers, interference temperature, and number of secondary users on the achievable capacity.

Quaternary Alkylammonium Conjugates of Steroids: Synthesis, Molecular Structure, and Biological Studies

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Bogumił Brycki

2015-11-01

Full Text Available The methods of synthesis as well as physical, spectroscopic (1H-NMR, 13C-NMR, and FT-IR, ESI-MS, and biological properties of quaternary and dimeric quaternary alkylammonium conjugates of steroids are presented. The results were contrasted with theoretical calculations (PM5 methods and potential pharmacological properties (PASS. Alkylammonium sterols exhibit a broad spectrum of antimicrobial activity comparable to squalamine.

Reduced Tract Integrity of the Model for Social Communication Is a Neural Substrate of Social Communication Deficits in Autism Spectrum Disorder

Science.gov (United States)

Lo, Yu-Chun; Chen, Yu-Jen; Hsu, Yung-Chin; Tseng, Wen-Yih Isaac; Gau, Susan Shur-Fen

2017-01-01

Background: Autism spectrum disorder (ASD) is a neurodevelopmental disorder with social communication deficits as one of the core symptoms. Recently, a five-level model for the social communication has been proposed in which white matter tracts corresponding to each level of the model are identified. Given that the model for social communication…

Effects of Video Modeling on the Instructional Efficiency of Simultaneous Prompting among Preschoolers with Autism Spectrum Disorder

Science.gov (United States)

Genc-Tosun, Derya; Kurt, Onur

2017-01-01

The purpose of the present study was to compare the effectiveness and efficiency of simultaneous prompting with and without video modeling in teaching food preparation skills to four participants with autism spectrum disorder, whose ages ranged from 5 to 6 years old. An adapted alternating treatment single-case experimental design was used to…

Particulate Matter Resuspension in Mississippi Bight Evaluated with CONCORDE's Synthesis Model

Science.gov (United States)

O'Brien, S. J.; Quas, L. M.; Miles, T. N.; Pan, C.; Cambazoglu, M. K.; Soto Ramos, I. M.; Greer, A. T.; Church, I.; Wiggert, J. D.

2017-12-01

The CONsortium for oil spill exposure pathways in COastal River-Dominated Ecosystems (CONCORDE) was established to investigate the complex fine-scale biological, chemical and physical interactions in a marine system controlled by pulsed-river plume dynamics. During CONCORDE's spring 2016 field campaign, the In Situ Ichthyoplankton Imaging System (ISIIS) on the R/V Point Sur and the Scanfish on the R/V Pelican comprehensively characterized the physical and biological structure in the region. Increased suspended particulate matter was observed by the ISIIS, with concentrations at depth sufficient to completely occlude the in situ images of planktonic organisms. Data was also collected on the continental shelf during the spring cruise by the RU31 glider in the proximity of the Mississippi River Delta, east of the ISIIS / Scanfish transects. Backscatter and salinity observed by the Scanfish and glider showed elevated suspended particulate matter and increased salinity, suggesting a linkage to shoreward advection from the continental shelf of oceanic waters that are sufficiently energetic to drive sediment resuspension. As part of the CONCORDE research effort, a four-dimensional biogeochemical/lower trophic level synthesis model for Mississippi Sound and Bight has been developed, based on the Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST) Modeling System. This study utilizes CONCORDE's synthesis model to investigate the physical forcing mechanisms affecting the increased suspended particulate matter concentration observed in the Mississippi Bight during spring 2016, and advection pathways between estuarine and shelf waters in the northern Gulf of Mexico. The results show that episodic, advection-driven resuspension is a critical aspect controlling suspended sediment distributions in Mississippi Bight, which has implications for observed spatio-temporal patterns of planktonic species.

Screening of broad spectrum natural pesticides against conserved target arginine kinase in cotton pests by molecular modeling.

Science.gov (United States)

Sakthivel, Seethalakshmi; Habeeb, S K M; Raman, Chandrasekar

2018-03-12

Cotton is an economically important crop and its production is challenged by the diversity of pests and related insecticide resistance. Identification of the conserved target across the cotton pest will help to design broad spectrum insecticide. In this study, we have identified conserved sequences by Expressed Sequence Tag profiling from three cotton pests namely Aphis gossypii, Helicoverpa armigera, and Spodoptera exigua. One target protein arginine kinase having a key role in insect physiology and energy metabolism was studied further using homology modeling, virtual screening, molecular docking, and molecular dynamics simulation to identify potential biopesticide compounds from the Zinc natural database. We have identified four compounds having excellent inhibitor potential against the identified broad spectrum target which are highly specific to invertebrates.

Spectrum-to-Spectrum Searching Using a Proteome-wide Spectral Library*

Science.gov (United States)

Yen, Chia-Yu; Houel, Stephane; Ahn, Natalie G.; Old, William M.

2011-01-01

The unambiguous assignment of tandem mass spectra (MS/MS) to peptide sequences remains a key unsolved problem in proteomics. Spectral library search strategies have emerged as a promising alternative for peptide identification, in which MS/MS spectra are directly compared against a reference library of confidently assigned spectra. Two problems relate to library size. First, reference spectral libraries are limited to rediscovery of previously identified peptides and are not applicable to new peptides, because of their incomplete coverage of the human proteome. Second, problems arise when searching a spectral library the size of the entire human proteome. We observed that traditional dot product scoring methods do not scale well with spectral library size, showing reduction in sensitivity when library size is increased. We show that this problem can be addressed by optimizing scoring metrics for spectrum-to-spectrum searches with large spectral libraries. MS/MS spectra for the 1.3 million predicted tryptic peptides in the human proteome are simulated using a kinetic fragmentation model (MassAnalyzer version2.1) to create a proteome-wide simulated spectral library. Searches of the simulated library increase MS/MS assignments by 24% compared with Mascot, when using probabilistic and rank based scoring methods. The proteome-wide coverage of the simulated library leads to 11% increase in unique peptide assignments, compared with parallel searches of a reference spectral library. Further improvement is attained when reference spectra and simulated spectra are combined into a hybrid spectral library, yielding 52% increased MS/MS assignments compared with Mascot searches. Our study demonstrates the advantages of using probabilistic and rank based scores to improve performance of spectrum-to-spectrum search strategies. PMID:21532008

Recent Progress in the Chemical Synthesis of Class II and S-Glycosylated Bacteriocins

Directory of Open Access Journals (Sweden)

François Bédard

2018-05-01

Full Text Available A wide variety of antimicrobial peptides produced by lactic acid bacteria (LAB have been identified and studied in the last decades. Known as bacteriocins, these ribosomally synthesized peptides inhibit the growth of a wide range of bacterial species through numerous mechanisms and show a great variety of spectrum of activity. With their great potential as antimicrobial additives and alternatives to traditional antibiotics in food preservation and handling, animal production and in veterinary and medical medicine, the demand for bacteriocins is rapidly increasing. Bacteriocins are most often produced by fermentation but, in several cases, the low isolated yields and difficulties associated with their purification seriously limit their use on a large scale. Chemical synthesis has been proposed for their production and recent advances in peptide synthesis methodologies have allowed the preparation of several bacteriocins. Moreover, the significant cost reduction for peptide synthesis reagents and building blocks has made chemical synthesis of bacteriocins more attractive and competitive. From a protein engineering point of view, the chemical approach offers many advantages such as the possibility to rapidly perform amino acid substitution, use unnatural or modified residues, and make backbone and side chain modifications to improve potency, modify the activity spectrum or increase the stability of the targeted bacteriocin. This review summarized synthetic approaches that have been developed and used in recent years to allow the preparation of class IIa bacteriocins and S-linked glycopeptides from LAB. Synthetic strategies such as the use of pseudoprolines, backbone protecting groups, microwave irradiations, selective disulfide bridge formation and chemical ligations to prepare class II and S-glycosylsated bacteriocins are discussed.

COSMIC EMULATION: FAST PREDICTIONS FOR THE GALAXY POWER SPECTRUM

Energy Technology Data Exchange (ETDEWEB)

Kwan, Juliana; Heitmann, Katrin; Habib, Salman; Frontiere, Nicholas; Pope, Adrian [High Energy Physics Division, Argonne National Laboratory, Lemont, IL 60439 (United States); Padmanabhan, Nikhil [Department of Physics, Yale University, 260 Whitney Ave., New Haven, CT 06520 (United States); Lawrence, Earl [Statistical Sciences, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Finkel, Hal [Argonne Leadership Computing Facility, Argonne National Laboratory, Lemont, IL 60439 (United States)

2015-09-01

The halo occupation distribution (HOD) approach has proven to be an effective method for modeling galaxy clustering and bias. In this approach, galaxies of a given type are probabilistically assigned to individual halos in N-body simulations. In this paper, we present a fast emulator for predicting the fully nonlinear galaxy–galaxy auto and galaxy–dark matter cross power spectrum and correlation function over a range of freely specifiable HOD modeling parameters. The emulator is constructed using results from 100 HOD models run on a large ΛCDM N-body simulation, with Gaussian Process interpolation applied to a PCA-based representation of the galaxy power spectrum. The total error is currently ∼1% in the auto correlations and ∼2% in the cross correlations from z = 1 to z = 0, over the considered parameter range. We use the emulator to investigate the accuracy of various analytic prescriptions for the galaxy power spectrum, parametric dependencies in the HOD model, and the behavior of galaxy bias as a function of HOD parameters. Additionally, we obtain fully nonlinear predictions for tangential shear correlations induced by galaxy–galaxy lensing from our galaxy–dark matter cross power spectrum emulator. All emulation products are publicly available at http://www.hep.anl.gov/cosmology/CosmicEmu/emu.html.

Spectrum recovery method based on sparse representation for segmented multi-Gaussian model

Science.gov (United States)

Teng, Yidan; Zhang, Ye; Ti, Chunli; Su, Nan

2016-09-01

Hyperspectral images can realize crackajack features discriminability for supplying diagnostic characteristics with high spectral resolution. However, various degradations may generate negative influence on the spectral information, including water absorption, bands-continuous noise. On the other hand, the huge data volume and strong redundancy among spectrums produced intense demand on compressing HSIs in spectral dimension, which also leads to the loss of spectral information. The reconstruction of spectral diagnostic characteristics has irreplaceable significance for the subsequent application of HSIs. This paper introduces a spectrum restoration method for HSIs making use of segmented multi-Gaussian model (SMGM) and sparse representation. A SMGM is established to indicating the unsymmetrical spectral absorption and reflection characteristics, meanwhile, its rationality and sparse property are discussed. With the application of compressed sensing (CS) theory, we implement sparse representation to the SMGM. Then, the degraded and compressed HSIs can be reconstructed utilizing the uninjured or key bands. Finally, we take low rank matrix recovery (LRMR) algorithm for post processing to restore the spatial details. The proposed method was tested on the spectral data captured on the ground with artificial water absorption condition and an AVIRIS-HSI data set. The experimental results in terms of qualitative and quantitative assessments demonstrate that the effectiveness on recovering the spectral information from both degradations and loss compression. The spectral diagnostic characteristics and the spatial geometry feature are well preserved.

Influence of hadronic interaction models and the cosmic ray spectrum on the high-energy atmospheric muon and neutrino flux

Directory of Open Access Journals (Sweden)

Desiati Paolo

2013-06-01

Full Text Available The recent observations of muon charge ratio up to about 10 TeV and of atmospheric neutrinos up to energies of about 400 TeV has triggered a renewed interest into the high-energy interaction models and cosmic ray primary composition. A reviewed calculation of lepton spectra produced in cosmic ray induced extensive air showers is carried out with a primary cosmic ray spectrum that fits the latest direct measurements below the knee. In order to achieve this, we used a full Monte Carlo method to derive the inclusive differential spectra (yields of muons, muon neutrinos and electron neutrinos at the surface for energies between 80 GeV and hundreds of PeV. Using these results the differential flux and the flavor ratios of leptons were calculated. The air shower simulator CORSIKA 6.990 was used for showering and propagation of the secondary particles through the atmosphere, employing the established high energy hadronic interaction models SIBYLL 2.1, QGSJet-01 and QGSJet-II-03. We show that the performance of the interaction models allows makes it possible to predict the spectra within experimental uncertainties, while SIBYLL generally yields a higher flux at the surface than the QGSJet models. The calculation of the flavor and charge ratios has lead to inconsistent results, mainly influenced by the different representations of the K/π ratio within the models. The influence of the knee of cosmic rays is reflected in the secondary spectra at energies between 100 and 200 TeV. Furthermore, we could quantify systematic uncertainties of atmospheric muon- and neutrino fluxes, associated to the models of the primary cosmic ray spectrum and the interaction models. For most recent parametrizations of the cosmic ray primary spectrum, atmospheric muons can be determined with an uncertainty smaller than +15/-13% of the average flux. Uncertainties of the muon and electron neutrino fluxes can be calculated within an average error of +32/-22% and +25

Modeling of composite synthesis in conditions of controlled thermal explosion

Science.gov (United States)

Kukta, Yaroslav; Knyazeva, Anna

2017-12-01

The paper proposes the model for the titanium-based composite synthesis from powders of titanium and carbon of non-stoichiometric composition. The model takes into account the mixture heating from chamber walls, the dependence of liquidus and solidus temperatures on the composition of reacting mixture and the formation of possible irreversible phases. The reaction retardation by the reaction product is taken into consideration in kinetic laws. As an example, the results of temperature and conversion level calculation are presented for the system Ti-C with the summary reaction for different temperatures of chamber walls heating. It was revealed that the reaction retardation being the reaction product can be the cause of incomplete conversion in the thermal explosion conditions. Non-stoichiometric composition leads to the conditions of degenerated mode when some additional heating is necessary to complete the reaction.

Missing baryonic resonances in the Hagedorn spectrum

Energy Technology Data Exchange (ETDEWEB)

Man Lo, Pok [University of Wroclaw, Institute of Theoretical Physics, Wroclaw (Poland); GSI, Extreme Matter Institute EMMI, Darmstadt (Germany); Marczenko, Michal; Sasaki, Chihiro [University of Wroclaw, Institute of Theoretical Physics, Wroclaw (Poland); Redlich, Krzysztof [University of Wroclaw, Institute of Theoretical Physics, Wroclaw (Poland); GSI, Extreme Matter Institute EMMI, Darmstadt (Germany); Duke University, Department of Physics, Durham, NC (United States)

2016-08-15

The hadronic medium of QCD is modeled as a gas of point-like hadrons, with its composition determined by the Hagedorn mass spectrum. The spectrum consists of a discrete and a continuous part. The former is determined by the experimentally confirmed resonances tabulated by the Particle Data Group (PDG), while the latter can be extracted from the existing lattice data. This formulation of the hadron resonance gas (HRG) provides a transparent framework to relate the fluctuation of conserved charges as calculated in the lattice QCD approach to the particle content of the medium. A comparison of the two approaches shows that the equation of state is well described by the standard HRG model, which includes only a discrete spectrum of known hadrons. The corresponding description in the strange sector, however, shows clear discrepancies, thus a continuous spectrum is added to incorporate the effect of missing resonances. We propose a method to extract the strange-baryon spectrum from the lattice data. The result is consistent with the trend set by the unconfirmed strange baryons resonances listed by the PDG, suggesting that most of the missing interaction strength for the strange baryons reside in the S = 1 sector. This scenario is also supported by recent lattice calculations, and might be important in the energy region covered by the NICA accelerator in Dubna, where in the heavy-ion collisions, baryons are the dominating degrees of freedom in the final state. (orig.)

Genetic Aspects of Autism Spectrum Disorders: Insights from Animal Models

Directory of Open Access Journals (Sweden)

Swati eBanerjee

2014-02-01

Full Text Available Autism spectrum disorders (ASD are a complex neurodevelopmental disorder that display a triad of core behavioral deficits including restricted interests, often accompanied by repetitive behavior, deficits in language and communication, and an inability to engage in reciprocal social interactions. ASD is among the most heritable disorders but is not a simple disorder with a singular pathology and has a rather complex etiology. It is interesting to note that perturbations in synaptic growth, development and stability underlie a variety of neuropsychiatric disorders, including ASD, schizophrenia, epilepsy and intellectual disability. Biological characterization of an increasing repertoire of synaptic mutants in various model organisms indicates synaptic dysfunction as causal in the pathophysiology of ASD. Our understanding of the genes and genetic pathways that contribute towards the formation, stabilization and maintenance of functional synapses coupled with an in-depth phenotypic analysis of the cellular and behavioral characteristics is therefore essential to unraveling the pathogenesis of these disorders. In this review, we discuss the genetic aspects of ASD emphasizing on the well conserved set of genes and genetic pathways implicated in this disorder, many of which contribute to synapse assembly and maintenance across species. We also review how fundamental research using animal models is providing key insights into the various facets of human ASD.

A smooth bouncing cosmology with scale invariant spectrum

International Nuclear Information System (INIS)

Creminelli, P.; Senatore, L.

2007-01-01

We present a bouncing cosmology which evolves from the contracting to the expanding phase in a smooth way, without developing instabilities or pathologies and remaining in the regime of validity of 4d effective field theory. A nearly scale invariant spectrum of perturbations is generated during the contracting phase by an isocurvature scalar with a negative exponential potential and then converted to adiabatic. The model predicts a slightly blue spectrum, n S > or approx. 1, no observable gravitational waves and a high (but model dependent) level of non-Gaussianities with local shape. The model represents an explicit and predictive alternative to inflation, although, at present, it is clearly less compelling. (author)

Modelling and synthesis of pharmaceutical processes: moving from batch to continuous

DEFF Research Database (Denmark)

Papadakis, Emmanouil

and to investigate/evaluate opportunities for continuous operation. To achieve the mentioned objectives the use of an integrated framework based on systematic model-based methods and tools is proposed. Computer-aided methods and tools are used to generate process knowledge and to evaluate different operational...... optimization studies are performed by defining optimization target based on the process analysis. The application of the developed integrated framework is highlighted through four case studies. In the first case study, the overall use of the framework is highlighted using the synthesis of ibuprofen...

Fast radio burst search: cross spectrum vs. auto spectrum method

Science.gov (United States)

Liu, Lei; Zheng, Weimin; Yan, Zhen; Zhang, Juan

2018-06-01

The search for fast radio bursts (FRBs) is a hot topic in current radio astronomy studies. In this work, we carry out a single pulse search with a very long baseline interferometry (VLBI) pulsar observation data set using both auto spectrum and cross spectrum search methods. The cross spectrum method, first proposed in Liu et al., maximizes the signal power by fully utilizing the fringe phase information of the baseline cross spectrum. The auto spectrum search method is based on the popular pulsar software package PRESTO, which extracts single pulses from the auto spectrum of each station. According to our comparison, the cross spectrum method is able to enhance the signal power and therefore extract single pulses from data contaminated by high levels of radio frequency interference (RFI), which makes it possible to carry out a search for FRBs in regular VLBI observations when RFI is present.

The Spectrum Sharing in Cognitive Radio Networks Based on Competitive Price Game

Directory of Open Access Journals (Sweden)

Y. B. Li

2012-09-01

Full Text Available The competitive price game model is used to analyze the spectrum sharing problem in the cognitive radio networks, and the spectrum sharing problem with the constraints of available spectrum resource from primary users is further discussed in this paper. The Rockafeller multiplier method is applied to deal with the constraints of available licensed spectrum resource, and the improved profits function is achieved, which can be used to measure the impact of shared spectrum price strategies on the system profit. However, in the competitive spectrum sharing problem of practical cognitive radio network, primary users have to determine price of the shared spectrum without the acknowledgement of the other primary user’s price strategies. Thus a fast gradient iterative calculation method of equilibrium price is proposed, only with acknowledgement of the price strategies of shared spectrum during last cycle. Through the adaptive iteration at the direction with largest gradient of improved profit function, the equilibrium price strategies can be achieved rapidly. It can also avoid the predefinition of adjustment factor according to the parameters of communication system in conventional linear iteration method. Simulation results show that the proposed competitive price spectrum sharing model can be applied in the cognitive radio networks with constraints of available licensed spectrum, and it has better convergence performance.

Low temperature synthesis of nanosized Mn1–xZnxFe2O4 ferrites ...

Indian Academy of Sciences (India)

Administrator

spectrum analysis were carried out to confirm the spinel phase formation as well as to ascertain the cation distri- bution in the ferrite ... structured materials technology opening up in the last few ... recent years, the design and synthesis of nano-magnetic particles ..... complex system like the ferrites where many cations are.

Robustness analysis of a green chemistry-based model for the classification of silver nanoparticles synthesis processes

Science.gov (United States)

This paper proposes a robustness analysis based on Multiple Criteria Decision Aiding (MCDA). The ensuing model was used to assess the implementation of green chemistry principles in the synthesis of silver nanoparticles. Its recommendations were also compared to an earlier develo...

Metabolic modeling of synthesis gas fermentation in bubble column reactors.

Science.gov (United States)

Chen, Jin; Gomez, Jose A; Höffner, Kai; Barton, Paul I; Henson, Michael A

2015-01-01

A promising route to renewable liquid fuels and chemicals is the fermentation of synthesis gas (syngas) streams to synthesize desired products such as ethanol and 2,3-butanediol. While commercial development of syngas fermentation technology is underway, an unmet need is the development of integrated metabolic and transport models for industrially relevant syngas bubble column reactors. We developed and evaluated a spatiotemporal metabolic model for bubble column reactors with the syngas fermenting bacterium Clostridium ljungdahlii as the microbial catalyst. Our modeling approach involved combining a genome-scale reconstruction of C. ljungdahlii metabolism with multiphase transport equations that govern convective and dispersive processes within the spatially varying column. The reactor model was spatially discretized to yield a large set of ordinary differential equations (ODEs) in time with embedded linear programs (LPs) and solved using the MATLAB based code DFBAlab. Simulations were performed to analyze the effects of important process and cellular parameters on key measures of reactor performance including ethanol titer, ethanol-to-acetate ratio, and CO and H2 conversions. Our computational study demonstrated that mathematical modeling provides a complementary tool to experimentation for understanding, predicting, and optimizing syngas fermentation reactors. These model predictions could guide future cellular and process engineering efforts aimed at alleviating bottlenecks to biochemical production in syngas bubble column reactors.

Microstrip natural wave spectrum mathematical model using partial inversion method

International Nuclear Information System (INIS)

Pogarsky, S.A.; Litvinenko, L.N.; Prosvirnin, S.L.

1995-01-01

It is generally agreed that both microstrip lines itself and different discontinuities based on microstrips are the most difficult problem for accurate electrodynamic analysis. Over the last years much has been published about principles and accurate (or full wave) methods of microstrip lines investigations. The growing interest for this problem may be explained by the microstrip application in the millimeter-wave range for purpose of realizing interconnects and a variety of passive components. At these higher operating rating frequencies accurate component modeling becomes more critical. A creation, examination and experimental verification of the accurate method for planar electrodynamical structures natural wave spectrum investigations are the objects of this manuscript. The moment method with partial inversion operator method using may be considered as a basical way for solving this problem. This method is outlook for accurate analysis of different planar discontinuities in microstrip: such as step discontinuities, microstrip turns, Y- and X-junctions and etc., substrate space steps dielectric constants and other anisotropy types

Vibrational interference effects in x-ray emission of a model water dimer: implications for the interpretation of the liquid spectrum.

Science.gov (United States)

Ljungberg, M P; Pettersson, L G M; Nilsson, A

2011-01-28

We apply the Kramers-Heisenberg formula to a model water dimer to discuss vibrational interference in the x-ray emission spectrum of the donor molecule for which the core-ionized potential energy surface is dissociative but bounded by the accepting molecule. A long core-hole lifetime leads to decay from Zundel-like, fully delocalized vibrational states in the intermediate potential without involvement of a specific dissociated component. Comparison is made to a model with an unbound intermediate state allowing dissociation to infinity which gives a sharp, fully dissociated feature, and a broad molecular peak at long core-hole life time. The implications of the vibrational interference effect on the liquid water spectrum are discussed and it is proposed that this mainly gives rise to an isotope-dependent asymmetrical broadening of the lone pair peak.

Mycogenic synthesis of silver nanoparticles by the Japanese environmental isolate Aspergillus tamarii

Energy Technology Data Exchange (ETDEWEB)

Rajesh Kumar, Ramasamy; Poornima Priyadharsani, Krishnamurthy; Thamaraiselvi, Kaliannan, E-mail: kthamaraiselvi@hotmail.com [Bharathidasan University, Laboratory of Molecular Microbial Bioremediation and Nanobiotechnology, Department of Environmental Biotechnology (India)

2012-05-15

In this study, an environmental friendly process for the synthesis of silver nanoparticles (AgNPs) using a fungus Aspergillus tamarii has been investigated. The process of silver ion reduction by the fungal extracellular filtrate was spontaneous which lead to the development of an easy process for synthesis of silver nanoparticles. The AgNPs formed were characterized using UV-Visible spectrum, FTIR, and SEM. The results revealed that silver ions reduction by the fungal extracellular filtrate started at 420 nm after 0.5 h of incubation time. The FTIR peaks were observed at 1393, 1820, 2727, and 3545 cm{sup -1}. The SEM result showed the distribution of spherical AgNPs ranging from 25 to 50 nm.

Security giving in surrogacy motherhood process as a caring model for commissioning mothers: A theory synthesis.

Science.gov (United States)

Zandi, Mitra; Vanaki, Zohreh; Shiva, Marziyeh; Mohammadi, Eesa; Bagheri-Lankarani, Narges

2016-07-01

Despite the increasing use of surrogacy, there are no caring theories/models that serve as the basis for nursing care to surrogacy commissioning mothers. This study has designed a model for caring of surrogacy commissioning mothers in 2013. The theory synthesis of Walker and Avant's strategies of theory construction (2011) was used to design a caring model/theory. The theory synthesis includes three stages: (i) selection of focal concept (the concept of "security giving in motherhood" was selected); (ii) review of studies in order to identify factors related to focal concept relevant studies (42 articles and 13 books) were reviewed, statements and concepts related to focal concept were then extracted and classified, and their relations were specified; and (iii) organization of concepts and statements within a relevant general and effective manifestation of the phenomenon under study which led to developing of a model. In this caring model/theory, entitled "security giving in surrogacy motherhood", nurses roles were conceptualized within the conceptual framework that includes three main roles: (i) coordination; (ii) participation; and (iii) security giving (physical, emotional, and legal support; empowerment; presence; relationship management between both parties and advocacy). Training surrogacy specialist nurses and establishment of surrogacy care centers are important factors for implementation of the model. This model could help to provided better caring for surrogacy clients, especially for commissioning mothers. © 2016 Japan Academy of Nursing Science.

A robust power spectrum split cancellation-based spectrum sensing method for cognitive radio systems

International Nuclear Information System (INIS)

Qi Pei-Han; Li Zan; Si Jiang-Bo; Gao Rui

2014-01-01

Spectrum sensing is an essential component to realize the cognitive radio, and the requirement for real-time spectrum sensing in the case of lacking prior information, fading channel, and noise uncertainty, indeed poses a major challenge to the classical spectrum sensing algorithms. Based on the stochastic properties of scalar transformation of power spectral density (PSD), a novel spectrum sensing algorithm, referred to as the power spectral density split cancellation method (PSC), is proposed in this paper. The PSC makes use of a scalar value as a test statistic, which is the ratio of each subband power to the full band power. Besides, by exploiting the asymptotic normality and independence of Fourier transform, the distribution of the ratio and the mathematical expressions for the probabilities of false alarm and detection in different channel models are derived. Further, the exact closed-form expression of decision threshold is calculated in accordance with Neyman—Pearson criterion. Analytical and simulation results show that the PSC is invulnerable to noise uncertainty, and can achive excellent detection performance without prior knowledge in additive white Gaussian noise and flat slow fading channels. In addition, the PSC benefits from a low computational cost, which can be completed in microseconds. (interdisciplinary physics and related areas of science and technology)

A robust power spectrum split cancellation-based spectrum sensing method for cognitive radio systems

Science.gov (United States)

Qi, Pei-Han; Li, Zan; Si, Jiang-Bo; Gao, Rui

2014-12-01

Spectrum sensing is an essential component to realize the cognitive radio, and the requirement for real-time spectrum sensing in the case of lacking prior information, fading channel, and noise uncertainty, indeed poses a major challenge to the classical spectrum sensing algorithms. Based on the stochastic properties of scalar transformation of power spectral density (PSD), a novel spectrum sensing algorithm, referred to as the power spectral density split cancellation method (PSC), is proposed in this paper. The PSC makes use of a scalar value as a test statistic, which is the ratio of each subband power to the full band power. Besides, by exploiting the asymptotic normality and independence of Fourier transform, the distribution of the ratio and the mathematical expressions for the probabilities of false alarm and detection in different channel models are derived. Further, the exact closed-form expression of decision threshold is calculated in accordance with Neyman—Pearson criterion. Analytical and simulation results show that the PSC is invulnerable to noise uncertainty, and can achive excellent detection performance without prior knowledge in additive white Gaussian noise and flat slow fading channels. In addition, the PSC benefits from a low computational cost, which can be completed in microseconds.

Medium usage model for the design of dynamic spectrum management in ISM bands

NARCIS (Netherlands)

Witvliet, B.A.; Bentum, M.J.; Schiphorst, R.; Slump, C.H.

2012-01-01

This paper presents a new approach for dynamic spectrum management for heterogeneous wireless devices. Local congestion degrades the reliability of wireless applications in the License Exempt bands. This leads to the research questions: (1) how to realize equal spectrum sharing between dissimilar

HMM Adaptation for child speech synthesis

CSIR Research Space (South Africa)

Govender, Avashna

2015-09-01

Full Text Available Hidden Markov Model (HMM)-based synthesis in combination with speaker adaptation has proven to be an approach that is well-suited for child speech synthesis. This paper describes the development and evaluation of different HMM-based child speech...

Was The Electromagnetic Spectrum A Blackbody Spectrum In The Early Universe?

OpenAIRE

Opher, Merav; Opher, Reuven

1997-01-01

It is assumed, in general, that the electromagnetic spectrum in the Primordial Universe was a blackbody spectrum in vacuum. We derive the electromagnetic spectrum, based on the Fluctuation-Dissipation Theorem that describes the electromagnetic fluctuations in a plasma. Our description includes thermal and collisional effects in a plasma. The electromagnetic spectrum obtained differs from the blackbody spectrum in vacuum at low frequencies. In particular, concentrating on the primordial nucleo...

Was The Electromagnetic Spectrum A Blackbody Spectrum In The Early Universe?

International Nuclear Information System (INIS)

Opher, M.; Opher, R.

1997-01-01

It is generally assumed that the electromagnetic spectrum in the primordial universe was a blackbody spectrum in vacuum. We derive the electromagnetic spectrum based on the fluctuation-dissipation theorem that describes the electromagnetic fluctuations in a plasma. Our description includes thermal and collisional effects in a plasma. The electromagnetic spectrum obtained differs from a blackbody spectrum in vacuum at low frequencies. In particular, concentrating on the primordial nucleosynthesis era, it has more energy than the blackbody spectrum for frequencies less than 3ω pe to 6ω pe , where ω pe is the electron plasma frequency. copyright 1997 The American Physical Society

Organic titanates: a model for activating rapid room-temperature synthesis of shape-controlled CsPbBr3 nanocrystals and their derivatives.

Science.gov (United States)

Fang, Shaofan; Li, Guangshe; Li, Huixia; Lu, Yantong; Li, Liping

2018-04-12

The application of lead halide perovskite nanocrystals is challenged by the lack of strategies in rapid room-temperature synthesis with controlled morphologies. Here, we report on an initial study of adopting organic titanates as a model activator that promotes rapid room-temperature synthesis of shape-controlled, highly luminescent CsPbBr3 nanocrystals and their derivatives.

Impact of malaria interventions on child mortality in endemic African settings: comparison and alignment between LiST and Spectrum-Malaria model.

Science.gov (United States)

Korenromp, Eline; Hamilton, Matthew; Sanders, Rachel; Mahiané, Guy; Briët, Olivier J T; Smith, Thomas; Winfrey, William; Walker, Neff; Stover, John

2017-11-07

In malaria-endemic countries, malaria prevention and treatment are critical for child health. In the context of intervention scale-up and rapid changes in endemicity, projections of intervention impact and optimized program scale-up strategies need to take into account the consequent dynamics of transmission and immunity. The new Spectrum-Malaria program planning tool was used to project health impacts of Insecticide-Treated mosquito Nets (ITNs) and effective management of uncomplicated malaria cases (CMU), among other interventions, on malaria infection prevalence, case incidence and mortality in children 0-4 years, 5-14 years of age and adults. Spectrum-Malaria uses statistical models fitted to simulations of the dynamic effects of increasing intervention coverage on these burdens as a function of baseline malaria endemicity, seasonality in transmission and malaria intervention coverage levels (estimated for years 2000 to 2015 by the World Health Organization and Malaria Atlas Project). Spectrum-Malaria projections of proportional reductions in under-five malaria mortality were compared with those of the Lives Saved Tool (LiST) for the Democratic Republic of the Congo and Zambia, for given (standardized) scenarios of ITN and/or CMU scale-up over 2016-2030. Proportional mortality reductions over the first two years following scale-up of ITNs from near-zero baselines to moderately higher coverages align well between LiST and Spectrum-Malaria -as expected since both models were fitted to cluster-randomized ITN trials in moderate-to-high-endemic settings with 2-year durations. For further scale-up from moderately high ITN coverage to near-universal coverage (as currently relevant for strategic planning for many countries), Spectrum-Malaria predicts smaller additional ITN impacts than LiST, reflecting progressive saturation. For CMU, especially in the longer term (over 2022-2030) and for lower-endemic settings (like Zambia), Spectrum-Malaria projects larger

Synthesis and electrochemical properties of {alpha}-MnO{sub 2} microspheres

Energy Technology Data Exchange (ETDEWEB)

Wang Hongen [College of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China); Zhengzhou Research Institute of CHALCO, Zhengzhou Research Institute of Light Metals, Zhengzhou 450041 (China); Qian Dong [College of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China)], E-mail: qiandong6@yahoo.com.cn

2008-06-15

We report the synthesis of {alpha}-MnO{sub 2} microspheres by a low-temperature hydrothermal method involving no templates or catalysts. The products were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy-dispersive X-ray spectrum (EDX), transmission electron microscopy (TEM), Fourier transform infrared spectrum (FT-IR), and Brunauer-Emmett-Teller (BET). The results show that the as-synthesized products are mainly composed of large quantities of {alpha}-MnO{sub 2} microspheres having a sea-urchin shape and a few microspheres constructed of small nanorods. Electrochemical characterization indicates that the resulting {alpha}-MnO{sub 2} microspheres display promising discharge properties than the commercial electrolytic manganese dioxides (EMD) when used as cathodes in alkaline Zn-MnO{sub 2} batteries.

Multiple Beta Spectrum Analysis Method Based on Spectrum Fitting

Energy Technology Data Exchange (ETDEWEB)

Lee, Uk Jae; Jung, Yun Song; Kim, Hee Reyoung [UNIST, Ulsan (Korea, Republic of)

2016-05-15

When the sample of several mixed radioactive nuclides is measured, it is difficult to divide each nuclide due to the overlapping of spectrums. For this reason, simple mathematical analysis method for spectrum analysis of the mixed beta ray source has been studied. However, existing research was in need of more accurate spectral analysis method as it has a problem of accuracy. The study will describe the contents of the separation methods of the mixed beta ray source through the analysis of the beta spectrum slope based on the curve fitting to resolve the existing problem. The fitting methods including It was understood that sum of sine fitting method was the best one of such proposed methods as Fourier, polynomial, Gaussian and sum of sine to obtain equation for distribution of mixed beta spectrum. It was shown to be the most appropriate for the analysis of the spectrum with various ratios of mixed nuclides. It was thought that this method could be applied to rapid spectrum analysis of the mixed beta ray source.

Noninvasive hemoglobin measurement using dynamic spectrum

Science.gov (United States)

Yi, Xiaoqing; Li, Gang; Lin, Ling

2017-08-01

Spectroscopy methods for noninvasive hemoglobin (Hgb) measurement are interfered by individual difference and particular weak signal. In order to address these problems, we have put forward a series of improvement methods based on dynamic spectrum (DS), including instrument design, spectrum extraction algorithm, and modeling approach. The instrument adopts light sources composed of eight laser diodes with the wavelength range from 600 nm to 1100 nm and records photoplethysmography signals at eight wavelengths synchronously. In order to simplify the optical design, we modulate the light sources with orthogonal square waves and design the corresponding demodulation algorithm, instead of adopting a beam-splitting system. A newly designed algorithm named difference accumulation has been proved to be effective in improving the accuracy of dynamic spectrum extraction. 220 subjects are involved in the clinical experiment. An extreme learning machine calibration model between the DS data and the Hgb levels is established. Correlation coefficient and root-mean-square error of prediction sets are 0.8645 and 8.48 g/l, respectively. The results indicate that the Hgb level can be derived by this approach noninvasively with acceptable precision and accuracy. It is expected to achieve a clinic application in the future.

Capacity limits of spectrum-sharing systems over hyper-fading channels

KAUST Repository

Ekin, Sabit

2011-01-20

Cognitive radio (CR) with spectrum-sharing feature is a promising technique to address the spectrum under-utilization problem in dynamically changing environments. In this paper, the achievable capacity gain of spectrum-sharing systems over dynamic fading environments is studied. To perform a general analysis, a theoretical fading model called hyper-fading model that is suitable to the dynamic nature of CR channel is proposed. Closed-form expressions of probability density function (PDF) and cumulative density function (CDF) of the signal-to-noise ratio (SNR) for secondary users (SUs) in spectrum-sharing systems are derived. In addition, the capacity gains achievable with spectrum-sharing systems in high and low power regions are obtained. The effects of different fading figures, average fading powers, interference temperatures, peak powers of secondary transmitters, and numbers of SUs on the achievable capacity are investigated. The analytical and simulation results show that the fading figure of the channel between SUs and primary base-station (PBS), which describes the diversity of the channel, does not contribute significantly to the system performance gain. © 2011 John Wiley & Sons, Ltd.

Capacity limits of spectrum-sharing systems over hyper-fading channels

KAUST Repository

Ekin, Sabit; Yilmaz, Ferkan; Ç elebi, Hasari Burak; Qaraqe, Khalid A.; Alouini, Mohamed-Slim; Serpedin, Erchin

2011-01-01

Cognitive radio (CR) with spectrum-sharing feature is a promising technique to address the spectrum under-utilization problem in dynamically changing environments. In this paper, the achievable capacity gain of spectrum-sharing systems over dynamic fading environments is studied. To perform a general analysis, a theoretical fading model called hyper-fading model that is suitable to the dynamic nature of CR channel is proposed. Closed-form expressions of probability density function (PDF) and cumulative density function (CDF) of the signal-to-noise ratio (SNR) for secondary users (SUs) in spectrum-sharing systems are derived. In addition, the capacity gains achievable with spectrum-sharing systems in high and low power regions are obtained. The effects of different fading figures, average fading powers, interference temperatures, peak powers of secondary transmitters, and numbers of SUs on the achievable capacity are investigated. The analytical and simulation results show that the fading figure of the channel between SUs and primary base-station (PBS), which describes the diversity of the channel, does not contribute significantly to the system performance gain. © 2011 John Wiley & Sons, Ltd.

Finding the K best synthesis plans.

Science.gov (United States)

Fagerberg, Rolf; Flamm, Christoph; Kianian, Rojin; Merkle, Daniel; Stadler, Peter F

2018-04-05

In synthesis planning, the goal is to synthesize a target molecule from available starting materials, possibly optimizing costs such as price or environmental impact of the process. Current algorithmic approaches to synthesis planning are usually based on selecting a bond set and finding a single good plan among those induced by it. We demonstrate that synthesis planning can be phrased as a combinatorial optimization problem on hypergraphs by modeling individual synthesis plans as directed hyperpaths embedded in a hypergraph of reactions (HoR) representing the chemistry of interest. As a consequence, a polynomial time algorithm to find the K shortest hyperpaths can be used to compute the K best synthesis plans for a given target molecule. Having K good plans to choose from has many benefits: it makes the synthesis planning process much more robust when in later stages adding further chemical detail, it allows one to combine several notions of cost, and it provides a way to deal with imprecise yield estimates. A bond set gives rise to a HoR in a natural way. However, our modeling is not restricted to bond set based approaches-any set of known reactions and starting materials can be used to define a HoR. We also discuss classical quality measures for synthesis plans, such as overall yield and convergency, and demonstrate that convergency has a built-in inconsistency which could render its use in synthesis planning questionable. Decalin is used as an illustrative example of the use and implications of our results.

Multiobjective Synthesis of Steerable UWB Circular Antenna Array considering Energy Patterns

Directory of Open Access Journals (Sweden)

Leopoldo A. Garza

2015-01-01

Full Text Available True-time delay antenna arrays have gained a prominent attention in ultrawideband (UWB applications such as directional communications and radar. This paper presents the design of steerable UWB circular array by using a multiobjective time-domain synthesis of energy pattern for circular antenna arrays. By this way we avoid individual beamforming for each frequency in UWB spectrum if the problem was addressed from the frequency domain. In order to obtain an energy pattern with low side lobe level and a desired main beam, the synthesis presented is performed by optimizing the true-time delays and amplitude coefficients for the antenna elements in a circular geometry. The method of Differential Evolution for Multiobjective Optimization (DEMO is used as the optimization algorithm in this work. This design of steerable UWB circular arrays considers the optimization of the true-time exciting delays and the amplitude coefficients across the antenna elements to operate with optimal performance in the whole azimuth plane (360°. A comparative analysis of the performance of the optimized design with the case of conventional progressive delay excitations is achieved. The provided results show a good performance for energy patterns and for their respective power patterns in the UWB spectrum.

Development of an Algorithm for Automatic Analysis of the Impedance Spectrum Based on a Measurement Model

Science.gov (United States)

Kobayashi, Kiyoshi; Suzuki, Tohru S.

2018-03-01

A new algorithm for the automatic estimation of an equivalent circuit and the subsequent parameter optimization is developed by combining the data-mining concept and complex least-squares method. In this algorithm, the program generates an initial equivalent-circuit model based on the sampling data and then attempts to optimize the parameters. The basic hypothesis is that the measured impedance spectrum can be reproduced by the sum of the partial-impedance spectra presented by the resistor, inductor, resistor connected in parallel to a capacitor, and resistor connected in parallel to an inductor. The adequacy of the model is determined by using a simple artificial-intelligence function, which is applied to the output function of the Levenberg-Marquardt module. From the iteration of model modifications, the program finds an adequate equivalent-circuit model without any user input to the equivalent-circuit model.

Effect of different BNCT protocols on DNA synthesis in precancerous and normal tissues in an experimental model of oral cancer

International Nuclear Information System (INIS)

Heber, Elisa M.; Aromando, Romina; Trivillin, Veronica A.; Itoiz, Maria E.; Kreimann, Erica L.; Schwint, Amanda E.; Nigg, David W.

2006-01-01

We previously reported the therapeutic success of different BNCT protocols in the treatment of oral cancer, employing the hamster cheek pouch model. The aim of the present study was to evaluate the effect of these BNCT protocols on DNA synthesis in precancerous and normal tissue in this model and assess the potential lag in the development of second primary tumors in precancerous tissue. The data are relevant to potential control of field cancerized tissue and tolerance of normal tissue. We evaluated DNA synthesis in precancerous and normal pouch tissue 1-30 days post-BNCT mediated by BPA, GB-10 or BPA + GB-10 employing incorporation of bromo-deoxyuridine as an end-point. The BNCT-induced potential lag in the development of second primary tumors in precancerous tissue was monitored. A drastic, statistically significant reduction in DNA synthesis occurred in pacancerous tissue as early as 1 day post-BNCT and was sustained at virtually all time points until 30 days post-BNCT for all protocols. The histological categories evaluated individually within precancerous tissue (dysplasia, hyperplasia and NUMF [no unusual microscopic features]) responded similarly. DNA synthesis in normal tissue treated with BNCT oscillated around the very low pre-treatment values. A BNCT-induced lag in the development of second primary tumors was observed. BNCT induced a drastic fall in DNA synthesis in precancerous tissue that would be associated to the observed lag in the development of second primary tumors. The minimum variations in DNA synthesis in BNCT-treated normal tissue would correlate with the absence of normal tissue radiotoxicity. The present data would contribute to optimize therapeutic efficacy in the treatment of field-cancerized areas. (author)

Partial Discharge Detection Using Low Cost RTL-SDR Model for Wideband Spectrum Sensing

DEFF Research Database (Denmark)

Mohamed, H.; Lazaridis, Pavlos; Upton, D.

2016-01-01

an optimal approach for PD signal analysis, and are very costly. In this paper an RTLSDR (Software Defined Radio) based spectrum analyser has been proposed in order to provide a potentially low cost solution for PD detection and monitoring. Initially, a portable spectrum analyser has been used for PD...

The importance of becoming double-stranded: Innate immunity and the kinetic model of HIV-1 central plus strand synthesis

International Nuclear Information System (INIS)

Poeschla, Eric

2013-01-01

Central initiation of plus strand synthesis is a conserved feature of lentiviruses and certain other retroelements. This complication of the standard reverse transcription mechanism produces a transient “central DNA flap” in the viral cDNA, which has been proposed to mediate its subsequent nuclear import. This model has assumed that the important feature is the flapped DNA structure itself rather than the process that produces it. Recently, an alternative kinetic model was proposed. It posits that central plus strand synthesis functions to accelerate conversion to the double-stranded state, thereby helping HIV-1 to evade single-strand DNA-targeting antiviral restrictions such as APOBEC3 proteins, and perhaps to avoid innate immune sensor mechanisms. The model is consistent with evidence that lentiviruses must often synthesize their cDNAs when dNTP concentrations are limiting and with data linking reverse transcription and uncoating. There may be additional kinetic advantages for the artificial genomes of lentiviral gene therapy vectors. - Highlights: • Two main functional models for HIV central plus strand synthesis have been proposed. • In one, a transient central DNA flap in the viral cDNA mediates HIV-1 nuclear import. • In the other, multiple kinetic consequences are emphasized. • One is defense against APOBEC3G, which deaminates single-stranded DNA. • Future questions pertain to antiviral restriction, uncoating and nuclear import

Adaptive spectrum decision framework for heterogeneous dynamic spectrum access networks

CSIR Research Space (South Africa)

Masonta, M

2015-09-01

Full Text Available Spectrum decision is the ability of a cognitive radio (CR) system to select the best available spectrum band to satisfy dynamic spectrum access network (DSAN) users¿ quality of service (QoS) requirements without causing harmful interference...

A global model of stress in parents of individuals with autism spectrum disorders (ASD

Directory of Open Access Journals (Sweden)

Pilar Pozo

2014-01-01

Full Text Available This research sought to analyse stress among mothers and fathers of individuals with autism spectrum disorders (ASD to determine the relevant variables for its explanation and the possible gender differences. To examine parents' stress, we propose a multidimensional model based on the Double ABCX theoretical model. We argue that the result of stress depends on the following four interrelated factors: the characteristics of the individual with ASD (the severity of the disorder and behaviour problems, the social supports, the parents' perception of the situation (evaluated by sense of coherence and the coping strategies. Fiftynine sets of parents (59 mothers and 59 fathers of individuals diagnosed with ASD participated in the study. The data were analysed using a path analysis through the LISREL 8.80 program. We obtained two empirical models of stress: one model for mothers and one for fathers. In both models, the severity of the disorder and the behaviour problems had a direct and positive effect on stress. The sense of coherence (SOC and active avoidance coping strategies had a mediating role in models. Social support was relevant only for mothers. Finally, the results offer some guidelines for professionals working with families.

Rate in template-directed polymer synthesis.

Science.gov (United States)

Saito, Takuya

2014-06-01

We discuss the temporal efficiency of template-directed polymer synthesis, such as DNA replication and transcription, under a given template string. To weigh the synthesis speed and accuracy on the same scale, we propose a template-directed synthesis (TDS) rate, which contains an expression analogous to that for the Shannon entropy. Increasing the synthesis speed accelerates the TDS rate, but the TDS rate is lowered if the produced sequences are diversified. We apply the TDS rate to some production system models and investigate how the balance between the speed and the accuracy is affected by changes in the system conditions.

Regulating the Emission Spectrum of CsPbBr₃ from Green to Blue via Controlling the Temperature and Velocity of Microchannel Reactor.

Science.gov (United States)

Tang, Yong; Lu, Hanguang; Rao, Longshi; Li, Zongtao; Ding, Xinrui; Yan, Caiman; Yu, Binhai

2018-03-02

The ability to precisely obtain tunable spectrum of lead halide perovskite quantum dots (QDs) is very important for applications, such as in lighting and display. Herein, we report a microchannel reactor method for synthesis of CsPbBr₃ QDs with tunable spectrum. By adjusting the temperature and velocity of the microchannel reactor, the emission peaks of CsPbBr₃ QDs ranging from 520 nm to 430 nm were obtained, which is wider than that of QDs obtained in a traditional flask without changing halide component. The mechanism of photoluminescence (PL) spectral shift of CsPbBr₃ QDs was investigated, the result shows that the supersaturation control enabled by the superior mass and heat transfer performance in the microchannel is the key to achieve the wide range of PL spectrum, with only a change in the setting of the temperature controller required. The wide spectrum of CsPbBr₃ QDs can be applied to light-emitting diodes (LEDs), photoelectric sensors, lasers, etc.

A fast quadrature-based numerical method for the continuous spectrum biphasic poroviscoelastic model of articular cartilage.

Science.gov (United States)

Stuebner, Michael; Haider, Mansoor A

2010-06-18

A new and efficient method for numerical solution of the continuous spectrum biphasic poroviscoelastic (BPVE) model of articular cartilage is presented. Development of the method is based on a composite Gauss-Legendre quadrature approximation of the continuous spectrum relaxation function that leads to an exponential series representation. The separability property of the exponential terms in the series is exploited to develop a numerical scheme that can be reduced to an update rule requiring retention of the strain history at only the previous time step. The cost of the resulting temporal discretization scheme is O(N) for N time steps. Application and calibration of the method is illustrated in the context of a finite difference solution of the one-dimensional confined compression BPVE stress-relaxation problem. Accuracy of the numerical method is demonstrated by comparison to a theoretical Laplace transform solution for a range of viscoelastic relaxation times that are representative of articular cartilage. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Diffuse Reflectance Spectroscopy of Hidden Objects. Part II: Recovery of a Target Spectrum.

Science.gov (United States)

Pomerantsev, Alexey L; Rodionova, Oxana Ye; Skvortsov, Alexej N

2017-08-01

In this study, we consider the reconstruction of a diffuse reflectance near-infrared spectrum of an object (target spectrum) in case the object is covered by an interfering absorbing and scattering layer. Recovery is performed using a new empirical method, which was developed in our previous study. We focus on a system, which consists of several layers of polyethylene (PE) film and underlayer objects with different spectral features. The spectral contribution of the interfering layer is modeled by a three-component two-parameter multivariate curve resolution (MCR) model, which was built and calibrated using spectrally flat objects. We show that this model is applicable to real objects with non-uniform spectra. Ultimately, the target spectrum can be reconstructed from a single spectrum of the covered target. With calculation methods, we are able to recover quite accurately the spectrum of a target even when the object is covered by 0.7 mm of PE.

A description of the location and structure of the essential spectrum of a model operator in a subspace of a Fock space

Energy Technology Data Exchange (ETDEWEB)

Yodgorov, G R [Navoi State Pedagogical Institute, Navoi (Uzbekistan); Ismail, F [Universiti Putra Malaysia, Selangor (Malaysia); Muminov, Z I [Malaysia – Japan International Institute of Technology, Kuala Lumpur (Malaysia)

2014-12-31

We consider a certain model operator acting in a subspace of a fermionic Fock space. We obtain an analogue of Faddeev's equation. We describe the location of the essential spectrum of the operator under consideration and show that the essential spectrum consists of the union of at most four segments. Bibliography: 19 titles.

Analysis of a gamma-ray spectrum by using a standard spectrum

International Nuclear Information System (INIS)

Tasaka, Kanji

1975-06-01

The standard spectrum method has been extended to take into account the energy dependence of a standard spectrum. The method analyses the observed gamma-ray spectrum by the least-square method, using an interpolated standard spectrum for expressing the line shape and a linear function for the background continuum. The interpolated standard spectrum is defined for each fitting interval by interpolating several standard spectra, which are derived directly from the observed spectra of single photopeaks each corresponding to the incident monochromatic gamma-rays by subtracting the background and smoothing the data. (author)

Quantum gravitational contributions to the cosmic microwave background anisotropy spectrum.

Science.gov (United States)

Kiefer, Claus; Krämer, Manuel

2012-01-13

We derive the primordial power spectrum of density fluctuations in the framework of quantum cosmology. For this purpose we perform a Born-Oppenheimer approximation to the Wheeler-DeWitt equation for an inflationary universe with a scalar field. In this way, we first recover the scale-invariant power spectrum that is found as an approximation in the simplest inflationary models. We then obtain quantum gravitational corrections to this spectrum and discuss whether they lead to measurable signatures in the cosmic microwave background anisotropy spectrum. The nonobservation so far of such corrections translates into an upper bound on the energy scale of inflation.

Modeling the relationship between photosynthetically active radiation and global horizontal irradiance using singular spectrum analysis

International Nuclear Information System (INIS)

Zempila, Melina-Maria; Taylor, Michael; Bais, Alkiviadis; Kazadzis, Stelios

2016-01-01

We report on the construction of generic models to calculate photosynthetically active radiation (PAR) from global horizontal irradiance (GHI), and vice versa. Our study took place at stations of the Greek UV network (UVNET) and the Hellenic solar energy network (HNSE) with measurements from NILU-UV multi-filter radiometers and CM pyranometers, chosen due to their long (≈1 M record/site) high temporal resolution (≈1 min) record that captures a broad range of atmospheric environments and cloudiness conditions. The uncertainty of the PAR measurements is quantified to be ±6.5% while the uncertainty involved in GHI measurements is up to ≈±7% according to the manufacturer. We show how multi-linear regression and nonlinear neural network (NN) models, trained at a calibration site (Thessaloniki) can be made generic provided that the input–output time series are processed with multi-channel singular spectrum analysis (M-SSA). Without M-SSA, both linear and nonlinear models perform well only locally. M-SSA with 50 time-lags is found to be sufficient for identification of trend, periodic and noise components in aerosol, cloud parameters and irradiance, and to construct regularized noise models of PAR from GHI irradiances. Reconstructed PAR and GHI time series capture ≈95% of the variance of the cross-validated target measurements and have median absolute percentage errors <2%. The intra-site median absolute error of M-SSA processed models were ≈8.2±1.7 W/m"2 for PAR and ≈9.2±4.2 W/m"2 for GHI. When applying the models trained at Thessaloniki to other stations, the average absolute mean bias between the model estimates and measured values was found to be ≈1.2 W/m"2 for PAR and ≈0.8 W/m"2 for GHI. For the models, percentage errors are well within the uncertainty of the measurements at all sites. Generic NN models were found to perform marginally better than their linear counterparts. - Highlights: • Generic linear regression and nonlinear neural network

Adolescent Siblings of Individuals with an Autism Spectrum Disorder: Testing a Diathesis-Stress Model of Sibling Well-Being

Science.gov (United States)

Orsmond, Gael I.; Seltzer, Marsha Mailick

2009-01-01

The purpose of this study was to test a diathesis-stress model of well-being for siblings who have a brother or sister with an autism spectrum disorder (ASD). Data were collected from 57 adolescents and their mothers. Sisters reported higher levels of depressive and anxiety symptoms than brothers. Having a family history of ASDs was associated…

Facile method for the synthesis of gold nanoparticles using an ion coater

Science.gov (United States)

Lee, Seung Han; Jung, Hyun Kyu; Kim, Tae Cheol; Kim, Chang Hee; Shin, Chang Hwan; Yoon, Tae-Sik; Hong, A.-Ra; Jang, Ho Seong; Kim, Dong Hun

2018-03-01

Herein we report a metal nanoparticle synthesis method based on a physical vapor deposition process instead of the conventional wet process of chemical reactions in liquids. A narrow size distribution of synthesized gold nanoparticles was obtained using an ion coater on glycerin at low vapor pressure. The nanoparticle size could be modulated by controlling the sputtering conditions especially the discharge current. Due to the formation of gold nanoparticles, a surface plasmon resonance peak appeared at ∼530 nm in the absorption spectrum. The surface plasmon resonance peak exhibited red-shift with increasing size of the gold nanoparticles. Our results provide a simple, environmental friendly method for the synthesis of metal nanoparticles by combine low-cost deposition apparatus and a liquid medium, which is free from toxic reagents.

Analytical energy spectrum for hybrid mechanical systems

International Nuclear Information System (INIS)

Zhong, Honghua; Xie, Qiongtao; Lee, Chaohong; Guan, Xiwen; Gao, Kelin; Batchelor, Murray T

2014-01-01

We investigate the energy spectrum for hybrid mechanical systems described by non-parity-symmetric quantum Rabi models. A set of analytical solutions in terms of the confluent Heun functions and their analytical energy spectrum is obtained. The analytical energy spectrum includes regular and exceptional parts, which are both confirmed by direct numerical simulation. The regular part is determined by the zeros of the Wronskian for a pair of analytical solutions. The exceptional part is relevant to the isolated exact solutions and its energy eigenvalues are obtained by analyzing the truncation conditions for the confluent Heun functions. By analyzing the energy eigenvalues for exceptional points, we obtain the analytical conditions for the energy-level crossings, which correspond to two-fold energy degeneracy. (paper)

Continuous Emission Spectrum Measurement for Electron Temperature Determination in Low-Temperature Collisional Plasmas

International Nuclear Information System (INIS)

Liu Qiuyan; Li Hong; Chen Zhipeng; Xie Jinlin; Liu Wandong

2011-01-01

Continuous emission spectrum measurement is applied for the inconvenient diagnostics of low-temperature collisional plasmas. According to the physical mechanism of continuous emission, a simplified model is presented to analyze the spectrum in low temperature plasma. The validity of this model is discussed in a wide range of discharge parameters, including electron temperature and ionization degree. Through the simplified model, the continuous emission spectrum in a collisional argon internal inductively coupled plasma is experimentally measured to determine the electron temperature distribution for different gas pressures and radio-frequency powers. The inverse Abel transform is also applied for a better spatially resoluted results. Meanwhile, the result of the continuous emission spectrum measurement is compared to that of the electrostatic double probes, which indicates the effectiveness of this method. (low temperature plasma)

Microwave-Promoted Synthesis of Sulfonated Metallophthalocyanines and Aggregation in Different Solvents

Directory of Open Access Journals (Sweden)

Zhenhua Cheng

2015-01-01

Full Text Available Five metallosulfophthalocyanines (Fe, Ni, Zn, Co, and Cu compounds were synthesized by microwave irradiation. Compared to the conventional method of synthesis in terms of reaction time and yields, the microwave-promoted synthesis is preferred with high product yield and short reaction time. All synthesized products were characterized with MALDI-TOF mass spectrum, Fourier transform infrared spectroscopy (FT-IR, ultraviolet-visible spectroscopy (UV-Vis, and X-ray diffraction (XRD. Aggregation behavior of the five metallosulfophthalocyanines (MSPc in different solvents was studied by UV-Vis spectroscopy separately in N,N-dimethyl formamide (DMF and NaOH aqueous solution (5%wt. A redshift of maximum absorption wavelength and deviations from Lambert-Beer law with increasing the concentration were observed. The dimerization equilibrium constants (K of the five MSPc were determined, respectively.

A Comparison of Least-to-Most Prompting and Video Modeling for Teaching Pretend Play Skills to Children with Autism Spectrum Disorder

Science.gov (United States)

Ulke-Kurkcuoglu, Burcu

2015-01-01

The aim of this study is to compare effectiveness and efficiency of least-to-most prompting and video modeling for teaching pretend play skills to children with autism spectrum disorder. The adapted alternating treatment model, a single-subject design, was used in the study. Three students, one girl and two boys, between the ages of 5-6…

Systematic literature review of methodologies and data sources of existing economic models across the full spectrum of Alzheimer's disease and dementia from apparently healthy through disease progression to end of life care: a systematic review protocol.

Science.gov (United States)

Karagiannidou, Maria; Wittenberg, Raphael; Landeiro, Filipa Isabel Trigo; Park, A-La; Fry, Andra; Knapp, Martin; Gray, Alastair M; Tockhorn-Heidenreich, Antje; Castro Sanchez, Amparo Yovanna; Ghinai, Isaac; Handels, Ron; Lecomte, Pascal; Wolstenholme, Jane

2018-06-08

Dementia is one of the greatest health challenges the world will face in the coming decades, as it is one of the principal causes of disability and dependency among older people. Economic modelling is used widely across many health conditions to inform decisions on health and social care policy and practice. The aim of this literature review is to systematically identify, review and critically evaluate existing health economics models in dementia. We included the full spectrum of dementia, including Alzheimer's disease (AD), from preclinical stages through to severe dementia and end of life. This review forms part of the Real world Outcomes across the Alzheimer's Disease spectrum for better care: multimodal data Access Platform (ROADMAP) project. Electronic searches were conducted in Medical Literature Analysis and Retrieval System Online, Excerpta Medica dataBASE, Economic Literature Database, NHS Economic Evaluation Database, Cochrane Central Register of Controlled Trials, Cost-Effectiveness Analysis Registry, Research Papers in Economics, Database of Abstracts of Reviews of Effectiveness, Science Citation Index, Turning Research Into Practice and Open Grey for studies published between January 2000 and the end of June 2017. Two reviewers will independently assess each study against predefined eligibility criteria. A third reviewer will resolve any disagreement. Data will be extracted using a predefined data extraction form following best practice. Study quality will be assessed using the Phillips checklist for decision analytic modelling. A narrative synthesis will be used. The results will be made available in a scientific peer-reviewed journal paper, will be presented at relevant conferences and will also be made available through the ROADMAP project. CRD42017073874. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Synthesis and characterization of zeolite material from coal ashes modified by surfactant

International Nuclear Information System (INIS)

Fungaro, D.A.; Borrely, S.I.

2010-01-01

Coal ash was used as starting material for zeolite synthesis by means of hydrothermal treatment. The surfactant-modified zeolite (SMZ) was prepared by adsorbing the cationic surfactant hexadecyltrimethylammonium bromide (HDTMA-Br) on the external surface of the zeolite from coal ash. The zeolite structure stability was monitored during the characterization of the materials by FTIR, XDR and SEM. The structural parameters of surfactant-modified zeolite are very close to that of corresponding non-modified zeolite which indicates that the crystalline nature of the zeolite remained intact after required chemical treatment with HDTMA-Br molecules and heating treatment for drying. The most intense peaks in the FTIR spectrum of HDTMA-Br were observed in SMZ spectrum confirming adsorption of surfactant on zeolites. (author)

Synthesis of puric bases labelled with carbon 14 and nitrogen 15

International Nuclear Information System (INIS)

Lamorre, Yves

1975-01-01

In this report for graduation in organic chemistry engineering, the author reports the synthesis of adenine 14 C-2 et 14 C-6 by two different chemical ways from two derivatives of imidazole. He has used adenine 14 C-6 to obtain hypoxanthine 14 C-6, and then, by enzymatic processing, uric acid 14 C-6. He reports the study of the production of guanine 14 C-2 by cyclization of silylated derivative of imidazole with the carbon 14 C sulphur. However, a method of complete synthesis of this same compound revealed to be more practical. This complete synthesis way allowed the labelling of guanine in positions 1, 2 and 3 by the 96 per cent isotopic nitrogen. Nitrogen in positions 7 and 9 could have been labelled by the same way from the ethyl cyanoacetate 15 N and from the sodium nitrite 15 N. The study of the mass spectrum of these compounds labelled with nitrogen 15 N allowed most of fragments obtained during this analysis to be identified [fr

Regulating the Emission Spectrum of CsPbBr3 from Green to Blue via Controlling the Temperature and Velocity of Microchannel Reactor

Science.gov (United States)

Tang, Yong; Lu, Hanguang; Rao, Longshi; Ding, Xinrui; Yan, Caiman; Yu, Binhai

2018-01-01

The ability to precisely obtain tunable spectrum of lead halide perovskite quantum dots (QDs) is very important for applications, such as in lighting and display. Herein, we report a microchannel reactor method for synthesis of CsPbBr3 QDs with tunable spectrum. By adjusting the temperature and velocity of the microchannel reactor, the emission peaks of CsPbBr3 QDs ranging from 520 nm to 430 nm were obtained, which is wider than that of QDs obtained in a traditional flask without changing halide component. The mechanism of photoluminescence (PL) spectral shift of CsPbBr3 QDs was investigated, the result shows that the supersaturation control enabled by the superior mass and heat transfer performance in the microchannel is the key to achieve the wide range of PL spectrum, with only a change in the setting of the temperature controller required. The wide spectrum of CsPbBr3 QDs can be applied to light-emitting diodes (LEDs), photoelectric sensors, lasers, etc. PMID:29498710

End of multifield inflation and the perturbation spectrum

International Nuclear Information System (INIS)

Gong, Jinn-Ouk

2007-01-01

We investigate the dynamics of inflation models driven by multiple, decoupled scalar fields and calculate the Hubble parameter and the amplitude of the lightest field at the end of inflation which may be responsible for interesting, or possibly dangerous cosmological consequences after inflation. The results are very simple and similar to those of the single field inflation, mainly depending on the underlying spectrum of the masses. The mass distribution is heavily constrained by the power spectrum of density perturbations P and the spectral index n s . The overall mass scale gives the amplitude of P, and n s is affected by the number of fields and the spacing between masses in the distribution. The dropout effect of the massive fields makes the perturbation spectrum typically redder than the single field inflation spectrum. We illustrate this using two different mass distributions

A CR Spectrum Allocation Algorithm in Smart Grid Wireless Sensor Network

Directory of Open Access Journals (Sweden)

Wei He

2014-10-01

Full Text Available Cognitive radio (CR method was introduced in smart grid communication systems to resolve potential maladies such as the coexistence of heterogeneous networks, overloaded data flow, diversity in data structures, and unstable quality of service (QOS. In this paper, a cognitive spectrum allocation algorithm based on non-cooperative game theory is proposed. The CR spectrum allocation model was developed by modifying the traditional game model via the insertion of a time variable and a critical function. The computing simulation result shows that the improved spectrum allocation algorithm can achieve stable spectrum allocation strategies and avoid the appearance of multi-Nash equilibrium at the expense of certain sacrifices in the system utility. It is suitable for application in distributed cognitive networks in power grids, thus contributing to the improvement of the isomerism and data capacity of power communication systems.

Synthesis of vitamin D and erythemal irradiance obtained with a multiband filter radiometer and annual variation analysis in Rio Gallegos, Argentina

Energy Technology Data Exchange (ETDEWEB)

Orte, P F [ANPCyT (Argentina); Wolfram, E A; Salvador, J; D' Elia, R; Quel, E J [CEILAP (CITEFA-CONICET) Villa Martelli, Buenos Aires (Argentina); Paes Leme, N, E-mail: porte@citefa.gov.ar [Instituto Nacional de Pesquisas Espaciais (Brazil)

2011-01-01

In this paper we examined the annual variability of the erythemal solar radiation (a health risk) and the solar irradiance for synthesis of vitamin D (a health benefit) in Rio Gallegos, Argentina. We use ultraviolet radiation measurements made by a multiband filter radiometer GUV-541 and a Brewer spectrophotometer located at CEILAP-RG Station (CITEFA-CONICET) (51 deg. 33' S, 69 deg. 19' W). These measurements are weighted with action spectra published by the CIE (International Commission on Illumination). An action spectrum describes the relative effectiveness of different wavelengths in the generation of a particular biological response. The analyzed data correspond to September 2008-December 2009 period. The methodology used to obtain the erythemal irradiance and synthesis of vitamin D values combines irradiance measurements of a multiband filter radiometer with modeled values (output of radiative transfer model) and measurements of a Brewer spectrophotometer. This procedure increases the instrumental capabilities of this instrument. The synthesis of vitamin D and erythema are affected by UVB solar radiation. Therefore, its effect is strongly dependent of the stratospheric ozone amount, which undergoes large variations in the Rio Gallegos city due to ozone hole passage and its influence on these sub-polar latitudes. We observed that could exist cases of sunburn for reasonable exposure in abnormal situations of low total ozone column, resulting in high levels of ultraviolet radiation. Furthermore, the synthesis of vitamin D through exposure to ultraviolet radiation would be lower than the appropriate values to the majority of the year for these latitudes. Therefore it is important to evaluate the annual variation of these quantities realizing seasonal balance between this health risk and this health benefit.

Synthesis of vitamin D and erythemal irradiance obtained with a multiband filter radiometer and annual variation analysis in Rio Gallegos, Argentina

International Nuclear Information System (INIS)

Orte, P F; Wolfram, E A; Salvador, J; D'Elia, R; Quel, E J; Paes Leme, N

2011-01-01

In this paper we examined the annual variability of the erythemal solar radiation (a health risk) and the solar irradiance for synthesis of vitamin D (a health benefit) in Rio Gallegos, Argentina. We use ultraviolet radiation measurements made by a multiband filter radiometer GUV-541 and a Brewer spectrophotometer located at CEILAP-RG Station (CITEFA-CONICET) (51 deg. 33' S, 69 deg. 19' W). These measurements are weighted with action spectra published by the CIE (International Commission on Illumination). An action spectrum describes the relative effectiveness of different wavelengths in the generation of a particular biological response. The analyzed data correspond to September 2008-December 2009 period. The methodology used to obtain the erythemal irradiance and synthesis of vitamin D values combines irradiance measurements of a multiband filter radiometer with modeled values (output of radiative transfer model) and measurements of a Brewer spectrophotometer. This procedure increases the instrumental capabilities of this instrument. The synthesis of vitamin D and erythema are affected by UVB solar radiation. Therefore, its effect is strongly dependent of the stratospheric ozone amount, which undergoes large variations in the Rio Gallegos city due to ozone hole passage and its influence on these sub-polar latitudes. We observed that could exist cases of sunburn for reasonable exposure in abnormal situations of low total ozone column, resulting in high levels of ultraviolet radiation. Furthermore, the synthesis of vitamin D through exposure to ultraviolet radiation would be lower than the appropriate values to the majority of the year for these latitudes. Therefore it is important to evaluate the annual variation of these quantities realizing seasonal balance between this health risk and this health benefit.

Constraining models of f(R) gravity with Planck and WiggleZ power spectrum data

Science.gov (United States)

Dossett, Jason; Hu, Bin; Parkinson, David

2014-03-01

In order to explain cosmic acceleration without invoking ``dark'' physics, we consider f(R) modified gravity models, which replace the standard Einstein-Hilbert action in General Relativity with a higher derivative theory. We use data from the WiggleZ Dark Energy survey to probe the formation of structure on large scales which can place tight constraints on these models. We combine the large-scale structure data with measurements of the cosmic microwave background from the Planck surveyor. After parameterizing the modification of the action using the Compton wavelength parameter B0, we constrain this parameter using ISiTGR, assuming an initial non-informative log prior probability distribution of this cross-over scale. We find that the addition of the WiggleZ power spectrum provides the tightest constraints to date on B0 by an order of magnitude, giving log10(B0) explanation.

Photovoltaic yield: correction method for the mismatch between the solar spectrum and the reference ASTMG AM1.5G spectrum

Directory of Open Access Journals (Sweden)

Mambrini Thomas

2015-01-01

Full Text Available We propose a method for a spectral correction of the predicted PV yield and we show the importance of the spectral mismatch on the solar cell. Indeed, currently predicted PV yield are made considering solar irradiation, ambient temperature, incidence angle and partially (or not the solar spectrum. However, the solar spectrum is not always the same. It varies depending on the site location, atmospheric conditions, time of the day...This may impact the photovoltaic solar cells differently according to their technology (crystalline Silicon, thin film, multi-junctions... This paper presents a method for calculating the correction of the short-circuit current of a photovoltaic cell due to the mismatch of the solar spectrum with the reference ASTM AM1.5G spectrum, for a specific site, throughout the year, using monthly data of AERONET (AErosol RObotic NETwork established by NASA and CNRS and the model SMARTS (simple model for atmospheric transmission of sunshine developed by the NREL. We applied this correction method on the site of Palaiseau (France, 48.7°N, 2.2°E, 156 m, close to our laboratory, just for comparison and the example of Blida (Algeria, 36°N, 2°E, 230 m is given for one year. This example illustrates the importance of this spectral correction to better estimate the photovoltaic yield. To be more precise, instead of modeling the solar spectral distribution, one can measure it with a spectro-radiometer, and then, derive the spectral mismatch correction. Some of our typical measurements are presented in this paper.

Modeling amorphous Si3B3N7: Structure and elastic properties

International Nuclear Information System (INIS)

Hannemann, A.; Schoen, J.C.; Jansen, M.; Putz, H.; Lengauer, T.

2004-01-01

We investigate the structure and elastic properties of the amorphous high-temperature ceramic a-Si 3 B 3 N 7 . Several different structural models are generated and their properties such as the radial and angular distribution functions, the degree of local order, the density, the bulk modulus and the phonon spectrum, are calculated and compared with the experiment. The best structural agreement between model and experimental observations is found for models exhibiting a certain degree of local ( 3 B 3 N 7 has not been synthesized by cooling from the melt but via the polymerization and subsequent pyrolysis of molecular precursors. Furthermore, we suggest that, due to the synthesis process, stable nanoscale cavities (diameter 3 )

Global assessment of ocean carbon export by combining satellite observations and food-web models

Science.gov (United States)

Siegel, D. A.; Buesseler, K. O.; Doney, S. C.; Sailley, S. F.; Behrenfeld, M. J.; Boyd, P. W.

2014-03-01

The export of organic carbon from the surface ocean by sinking particles is an important, yet highly uncertain, component of the global carbon cycle. Here we introduce a mechanistic assessment of the global ocean carbon export using satellite observations, including determinations of net primary production and the slope of the particle size spectrum, to drive a food-web model that estimates the production of sinking zooplankton feces and algal aggregates comprising the sinking particle flux at the base of the euphotic zone. The synthesis of observations and models reveals fundamentally different and ecologically consistent regional-scale patterns in export and export efficiency not found in previous global carbon export assessments. The model reproduces regional-scale particle export field observations and predicts a climatological mean global carbon export from the euphotic zone of 6 Pg C yr-1. Global export estimates show small variation (typically model parameter values. The model is also robust to the choices of the satellite data products used and enables interannual changes to be quantified. The present synthesis of observations and models provides a path for quantifying the ocean's biological pump.

AN ULTRA-DEEP NEAR-INFRARED SPECTRUM OF A COMPACT QUIESCENT GALAXY AT z = 2.2

International Nuclear Information System (INIS)

Kriek, Mariska; Van Dokkum, Pieter G.; Marchesini, Danilo; Labbe, Ivo; Franx, Marijn; Quadri, Ryan F.; Illingworth, Garth D.

2009-01-01

Several recent studies have shown that about half of the massive galaxies at z ∼ 2 are in a quiescent phase. Moreover, these galaxies are commonly found to be ultra-compact with half-light radii of ∼1 kpc. We have obtained a ∼29 hr spectrum of a typical quiescent, ultra-dense galaxy at z = 2.1865 with the Gemini Near-Infrared Spectrograph. The spectrum exhibits a strong optical break and several absorption features, which have not previously been detected in z > 2 quiescent galaxies. Comparison of the spectral energy distribution with stellar population synthesis models implies a low star formation rate (SFR) of 1-3 M sun yr -1 , an age of 1.3-2.2 Gyr, and a stellar mass of ∼2 x 10 11 M sun . We detect several faint emission lines, with emission-line ratios of [N II]/Hα, [S II]/Hα, and [O II]/[O III] typical of low-ionization nuclear emission-line regions. Thus, neither the stellar continuum nor the nebular emission implies active star formation. The current SFR is <1% of the past average SFR. If this galaxy is representative of compact quiescent galaxies beyond z = 2, it implies that quenching of star formation is extremely efficient and also indicates that low luminosity active galactic nuclei (AGNs) could be common in these objects. Nuclear emission is a potential concern for the size measurement. However, we show that the AGN contributes ∼<8% to the rest-frame optical emission. A possible post-starburst population may affect size measurements more strongly; although a 0.5 Gyr old stellar population can make up ∼<10% of the total stellar mass, it could account for up to ∼40% of the optical light. Nevertheless, this spectrum shows that this compact galaxy is dominated by an evolved stellar population.

Iron zircon pigment synthesis: Proposal of a mixing index for the raw materials mixtures

International Nuclear Information System (INIS)

Zumaquero, E.; Ortsb, M.J.; Sanz, V.; Mestre, S.

2017-01-01

Iron zircon coral pigments are very interesting from an industrial point of view because of their high colouring power and their stability at high temperatures. However, the pigment's synthesis is particularly troublesome due to its specific reaction mechanism. As an encapsulated pigment it becomes very important how the raw materials are distributed in the reaction mixture. To evaluate the effectiveness of the mixing process, it would be convenient to define a parameter, that is the mixing index, to estimate the degree of homogeneity of the system. In the current investigation, a mixing index is proposed derived from the power spectrum of Fourier transform of scanning electron microscope (SEM) images of the raw material mixture. Concretely, the number of pixels in a certain range of values in the image of the power spectrum, seems to behave relatively well as mixing index. This index allows us to distinguish between samples with different zirconia and iron oxide used as precursors. The proposed mixing index seems to be related to the colouring power of the final pigment when the synthesis generates enough zircon to encapsulate hematite particles. [es

Multislot Simultaneous Spectrum Sensing and Energy Harvesting in Cognitive Radio

Directory of Open Access Journals (Sweden)

Xin Liu

2016-07-01

Full Text Available In cognitive radio (CR, the spectrum sensing of the primary user (PU may consume some electrical power from the battery capacity of the secondary user (SU, resulting in a decrease in the transmission power of the SU. In this paper, a multislot simultaneous spectrum sensing and energy harvesting model is proposed, which uses the harvested radio frequency (RF energy of the PU signal to supply the spectrum sensing. In the proposed model, the sensing duration is divided into multiple sensing slots consisting of one local-sensing subslot and one energy-harvesting subslot. If the PU is detected to be present in the local-sensing subslot, the SU will harvest RF energy of the PU signal in the energy-harvesting slot, otherwise, the SU will continue spectrum sensing. The global decision on the presence of the PU is obtained through combining local sensing results from all the sensing slots by adopting “Or-logic Rule”. A joint optimization problem of sensing time and time splitter factor is proposed to maximize the throughput of the SU under the constraints of probabilities of false alarm and detection and energy harvesting. The simulation results have shown that the proposed model can clearly improve the maximal throughput of the SU compared to the traditional sensing-throughput tradeoff model.

Synthesis of nano-sized amorphous boron powders through active dilution self-propagating high-temperature synthesis method

Energy Technology Data Exchange (ETDEWEB)

Wang, Jilin [The State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Gu, Yunle [School of Material Science and Engineering, Wuhan Institute of Technology, Wuhan 430073 (China); Li, Zili [The State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Wang, Weimin, E-mail: wangwm@hotmail.com [The State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Fu, Zhengyi [The State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China)

2013-06-01

Graphical abstract: Nano-sized amorphous boron powders were synthesized by active dilution self-propagating high-temperature synthesis (SHS) method. The effects of endothermic reaction rate, the possible chemical reaction mechanism and active dilution model for synthesis of the product were also discussed. Highlights: ► Nano-sized amorphous boron powders were synthesized by active dilution self-propagating high-temperature synthesis method. ► The morphology, particle size and purity of the samples could be effectively controlled via changing the endothermic rate. ► The diluter KBH{sub 4} played an important role in active dilution synthesis of amorphous nano-sized boron powders. ► The active dilution method could be further popularized and become a common approach to prepare various inorganic materials. - Abstract: Nano-sized amorphous boron powders were synthesized by active dilution self-propagating high-temperature synthesis (SHS) method at temperatures ranging from 700 °C to 850 °C in a SHS furnace using Mg, B{sub 2}O{sub 3} and KBH{sub 4} as raw materials. Samples were characterized by X-ray powder diffraction (XRD), Laser particle size analyzer, Fourier transform infrared spectra (FTIR), X-ray energy dispersive spectroscopy (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution transmission TEM (HRTEM). The boron powders demonstrated an average particle size of 50 nm with a purity of 95.64 wt.%. The diluter KBH{sub 4} played an important role in the active dilution synthesis of amorphous nano-sized boron powders. The effects of endothermic reaction rate, the possible chemical reaction mechanism and active dilution model for synthesis of the product were also discussed.

Synthesis of nano-sized amorphous boron powders through active dilution self-propagating high-temperature synthesis method

International Nuclear Information System (INIS)

Wang, Jilin; Gu, Yunle; Li, Zili; Wang, Weimin; Fu, Zhengyi

2013-01-01

Graphical abstract: Nano-sized amorphous boron powders were synthesized by active dilution self-propagating high-temperature synthesis (SHS) method. The effects of endothermic reaction rate, the possible chemical reaction mechanism and active dilution model for synthesis of the product were also discussed. Highlights: ► Nano-sized amorphous boron powders were synthesized by active dilution self-propagating high-temperature synthesis method. ► The morphology, particle size and purity of the samples could be effectively controlled via changing the endothermic rate. ► The diluter KBH 4 played an important role in active dilution synthesis of amorphous nano-sized boron powders. ► The active dilution method could be further popularized and become a common approach to prepare various inorganic materials. - Abstract: Nano-sized amorphous boron powders were synthesized by active dilution self-propagating high-temperature synthesis (SHS) method at temperatures ranging from 700 °C to 850 °C in a SHS furnace using Mg, B 2 O 3 and KBH 4 as raw materials. Samples were characterized by X-ray powder diffraction (XRD), Laser particle size analyzer, Fourier transform infrared spectra (FTIR), X-ray energy dispersive spectroscopy (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution transmission TEM (HRTEM). The boron powders demonstrated an average particle size of 50 nm with a purity of 95.64 wt.%. The diluter KBH 4 played an important role in the active dilution synthesis of amorphous nano-sized boron powders. The effects of endothermic reaction rate, the possible chemical reaction mechanism and active dilution model for synthesis of the product were also discussed

Effects of Mother-Delivered Social Stories and Video Modeling in Teaching Social Skills to Children with Autism Spectrum Disorders

Science.gov (United States)

Acar, Cimen; Tekin-Iftar, Elif; Yikmis, Ahmet

2017-01-01

An adapted alternating treatments design was used to compare mother-developed and delivered social stories and video modeling in teaching social skills to children with autism spectrum disorder (ASD). Mothers' opinions about the social validity of the study were also examined. Three mother-child dyads participated in the study. Results showed that…

Uncertainty and Sensitivity Analysis for an Ibuprofen Synthesis Model Based on Hoechst Path

DEFF Research Database (Denmark)

da Conceicao Do Carmo Montes, Frederico; Gernaey, Krist V.; Sin, Gürkan

2017-01-01

into consideration the effects of temperature, acidity, and the choice of the catalyst. Parameter estimation and uncertainty analysis were conducted on the kinetic model parameters using experimental data available in the literature. Finally, one factor at a time sensitivity analysis in the form of deviations......The pharmaceutical industry faces several challenges and barriers when implementing new or improving current pharmaceutical processes, such as competition from generic drug manufacturers and stricter regulations from the U.S. Food and Drug Administration and the European Medicine agency. The demand...... for efficient and reliable models to simulate and design/improve pharmaceutical processes is therefore increasing. For the case of ibuprofen, a well-known anti-inflammatory drug, the existing models do not include its complete synthesis path, usually referring only to one out of aset of different reactions...

Efficient response spectrum analysis of a reactor using Model Order Reduction

International Nuclear Information System (INIS)

Oh, Jin Ho; Choi, Jin Bok; Ryu, Jeong Soo

2012-01-01

A response spectrum analysis (RSA) has been widely used to evaluate the structural integrity of various structural components in the nuclear industry. However, solving the large and complex structural systems numerically using the RSA requires a considerable amount of computational resources and time. To overcome this problem, this paper proposes the RSA based on the model order reduction (MOR) technique achieved by applying a projection from a higher order to a lower order space using Krylov subspaces generated by the Arnoldi algorithm. The dynamic characteristics of the final reduced system are almost identical with those of the full system by matching the moments of the reduced system with those of the full system up to the required nth order. It is remarkably efficient in terms of computation time and does not require a global system. Numerical examples demonstrate that the proposed method saves computational costs effectively, and provides a reduced system framework that predicts the accurate responses of a global system

[Neuropsychological models of autism spectrum disorders - behavioral evidence and functional imaging].

Science.gov (United States)

Dziobek, Isabel; Bölte, Sven

2011-03-01

To review neuropsychological models of theory of mind (ToM), executive functions (EF), and central coherence (CC) as framework for cognitive abnormalities in autism spectrum disorders (ASD). Behavioral and functional imaging studies are described that assess social-cognitive, emotional, and executive functions as well as locally oriented perception in ASD. Impairments in ToM and EF as well as alterations in CC are frequently replicated phenomena in ASD. Especially problems concerning social perception and ToM have high explanatory value for clinical symptomatology. Brain activation patterns differ between individuals with and without ASD for ToM, EF, und CC functions. An approach focussing on reduced cortical connectivity seems to be increasingly favored over explanations focussing on single affected brain sites. A better understanding of the complexities of ASD in future research demands the integration of clinical, neuropsychological, functional imaging, and molecular genetics evidence. Weaknesses in ToM and EF as well as strengths in detail-focussed perception should be used for individual intervention planning.

Synthesis of tungsten oxide, silver, and gold nanoparticles by radio frequency plasma in water

International Nuclear Information System (INIS)

Hattori, Yoshiaki; Nomura, Shinfuku; Mukasa, Shinobu; Toyota, Hiromichi; Inoue, Toru; Usui, Tomoya

2013-01-01

Highlights: •RF plasma in water was used for nanoparticle synthesis. •Nanoparticles were produced from erosion of metallic electrode. •Rectangular and spherical tungsten oxide nanoparticles were produced. •No oxidations of the silver and gold spherical nanoparticles were produced. -- Abstract: A process for synthesis of nanoparticles using plasma in water generated by a radio frequency of 27.12 MHz is proposed. Tungsten oxide, silver, and gold nanoparticles were produced at 20 kPa through erosion of a metallic electrode exposed to plasma. Characterization of the produced nanoparticles was carried out by XRD, absorption spectrum, and TEM. The nanoparticle sizes were compared with those produced by a similar technique using plasma in liquid

Yunnan-III models for evolutionary population synthesis

Science.gov (United States)

Zhang, F.; Li, L.; Han, Z.; Zhuang, Y.; Kang, X.

2013-02-01

We build the Yunnan-III evolutionary population synthesis (EPS) models by using the mesa stellar evolution code, BaSeL stellar spectra library and the initial mass functions (IMFs) of Kroupa and Salpeter, and present colours and integrated spectral energy distributions (ISEDs) of solar-metallicity stellar populations (SPs) in the range of 1 Myr to 15 Gyr. The main characteristic of the Yunnan-III EPS models is the usage of a set of self-consistent solar-metallicity stellar evolutionary tracks (the masses of stars are from 0.1 to 100 M⊙). This set of tracks is obtained by using the state-of-the-art mesa code. mesa code can evolve stellar models through thermally pulsing asymptotic giant branch (TP-AGB) phase for low- and intermediate-mass stars. By comparisons, we confirm that the inclusion of TP-AGB stars makes the V - K, V - J and V - R colours of SPs redder and the infrared flux larger at ages log(t/yr) ≳ 7.6 [the differences reach the maximum at log(t/yr) ˜ 8.6, ˜0.5-0.2 mag for colours, approximately two times for K-band flux]. We also find that the colour-evolution trends of Model with-TPAGB at intermediate and large ages are similar to those from the starburst99 code, which employs the Padova-AGB stellar library, BaSeL spectral library and the Kroupa IMF. At last, we compare the colours with the other EPS models comprising TP-AGB stars (such as CB07, M05, V10 and POPSTAR), and find that the B - V colour agrees with each other but the V-K colour shows a larger discrepancy among these EPS models [˜1 mag when 8 ≲ log(t/yr) ≲ 9]. The stellar evolutionary tracks, isochrones, colours and ISEDs can be obtained on request from the first author or from our website (http://www1.ynao.ac.cn/~zhangfh/). Using the isochrones, you can build your EPS models. Now the format of stellar evolutionary tracks is the same as that in the starburst99 code; you can put them into the starburst99 code and get the SP's results. Moreover, the colours involving other passbands

Solving fault diagnosis problems linear synthesis techniques

CERN Document Server

Varga, Andreas

2017-01-01

This book addresses fault detection and isolation topics from a computational perspective. Unlike most existing literature, it bridges the gap between the existing well-developed theoretical results and the realm of reliable computational synthesis procedures. The model-based approach to fault detection and diagnosis has been the subject of ongoing research for the past few decades. While the theoretical aspects of fault diagnosis on the basis of linear models are well understood, most of the computational methods proposed for the synthesis of fault detection and isolation filters are not satisfactory from a numerical standpoint. Several features make this book unique in the fault detection literature: Solution of standard synthesis problems in the most general setting, for both continuous- and discrete-time systems, regardless of whether they are proper or not; consequently, the proposed synthesis procedures can solve a specific problem whenever a solution exists Emphasis on the best numerical algorithms to ...

A distributed supervisor synthesis approach based on weak bisimulation

NARCIS (Netherlands)

Su, Rong; Thistle, J.G.; Lafortune, S.; Lin, F.; Tilbury, D.

2006-01-01

It is well known that space and time complexity is one of the main bottlenecks of supervisor synthesis. The model of a large system is usually too big to be explicitly expressed, owing to composition of local components’ models, making supervisor synthesis difficult, if still possible. In this paper

Synthesis and Molecular Modeling of Thermally Stable DNA G-Quadruplexes with Anthraquinone Insertions

DEFF Research Database (Denmark)

Gouda, Alaa S.; Amine, Mahasen S.; Pedersen, Erik Bjerregaard

2017-01-01

Two new phosphoramidite building blocks for DNA synthesis were synthesized from 1,5- and 2,6-dihydroxyanthraquinones through alkylation with 3-bromo-1-propanol followed by DMT-protection. The novel synthesized 1,5- and 2,6-disubstituted anthraquinone monomers H15 and H26 are incorporated into a G...... anthraquinone-modified quadruplexes revealed no change of the antiparallel structure when compared with the wild type under potassium buffer conditions. The significantly increased thermostabilities were interpreted by molecular modeling of anthraquinone-modified G-quadruplexes....

The psychological synthesis evaluated by the interactive model A síntese psicológica avaliada pelo modelo interativo

Directory of Open Access Journals (Sweden)

Álvaro Tamayo

2010-01-01

Full Text Available The purpose of this article was to elaborate a model to evaluate the synthesis process resulting from the interaction which is established between opposing constructs, like gender schemas. In social psychology, the existence of opposites is possible to be detecting in contemporary theories, such as individualism versus collectivism and masculinity versus femininity. In all these themes, opposites assume both an oppositional and complementary attitude, but little relevance has been given to the process of synthesis. The Interactive Model was elaborated in an attempt to mathematically express the synthesis process and open up the possibility of studying human personality from a new perspective - the Psychological Synthesis.O propósito deste estudo foi elaborar um modelo para avaliar o processo de síntese resultante da interação que se estabelece entre constructos com naturezas opostas, como os esquemas de gênero. Em psicologia social, a existência dos opostos pode ser detectada em teorias contemporâneas, tais como: individualismo versus coletivismo e masculinidade versus feminilidade. Em todos estes temas, os opostos assumem tanto uma postura de oposição quanto uma postura complementar, mas pouca relevância tem sido dada ao processo de síntese. O Modelo Interativo foi elaborado na tentativa de expressar matematicamente este processo de síntese, e abre a possibilidade de se estudar a personalidade a partir de uma nova perspectiva - a Síntese Psicológica.

Galactic densities, substructure and the initial power spectrum

International Nuclear Information System (INIS)

Bullock, J.S.; Zentner, A.R.

2003-01-01

Although the currently favored cold dark matter plus cosmological constant model for structure formation assumes an n = 1 scale-invariant initial power spectrum, most inflation models produce at least mild deviations from n = 1. Because the lever arm from the CMB normalization to galaxy scales is long, even a small 'tilt' can have important implications for galactic observations. Here we calculate the COBS-normalized power spectra for several well-motivated models of inflation and compute implications for the substructure content and central densities of galaxy halos. Using an analytic model, normalized against N-body simulations, we show that while halos in the standard (n = 1) model are overdense by a factor of ∼ 6 compared to observations, several of our example inflation+LCDM models predict halo densities well within the range of observations, which prefer models with n ∼ 0.85. We go on to use a semi-analytic model (also normalized against N-body simulations) to follow the merger histories of galaxy-sized halos and track the orbital decay, disruption, and evolution of the merging substructure. Models with n ∼ 0.85 predict a factor of ∼ 3 fewer subhalos at a fixed circular velocity than the standard n 1 case. Although this level of reduction does not resolve the 'dwarf satellite problem', it does imply that the level of feedback required to match the observed number of dwarfs is sensitive to the initial power spectrum. Finally, the fraction of galaxy-halo mass that is bound up in substructure is consistent with limits imposed by multiply imaged quasars for all models considered: f sat > 0.01 even for an effective tilt of n ∼ 0.8. We conclude that, at their current level, lensing constraints of this kind do not provide an interesting probe of the primordial power spectrum

Particle precipitation: How the spectrum fit impacts atmospheric chemistry

Science.gov (United States)

Wissing, J. M.; Nieder, H.; Yakovchouk, O. S.; Sinnhuber, M.

2016-11-01

Particle precipitation causes atmospheric ionization. Modeled ionization rates are widely used in atmospheric chemistry/climate simulations of the upper atmosphere. As ionization rates are based on particle measurements some assumptions concerning the energy spectrum are required. While detectors measure particles binned into certain energy ranges only, the calculation of a ionization profile needs a fit for the whole energy spectrum. Therefore the following assumptions are needed: (a) fit function (e.g. power-law or Maxwellian), (b) energy range, (c) amount of segments in the spectral fit, (d) fixed or variable positions of intersections between these segments. The aim of this paper is to quantify the impact of different assumptions on ionization rates as well as their consequences for atmospheric chemistry modeling. As the assumptions about the particle spectrum are independent from the ionization model itself the results of this paper are not restricted to a single ionization model, even though the Atmospheric Ionization Module OSnabrück (AIMOS, Wissing and Kallenrode, 2009) is used here. We include protons only as this allows us to trace changes in the chemistry model directly back to the different assumptions without the need to interpret superposed ionization profiles. However, since every particle species requires a particle spectrum fit with the mentioned assumptions the results are generally applicable to all precipitating particles. The reader may argue that the selection of assumptions of the particle fit is of minor interest, but we would like to emphasize on this topic as it is a major, if not the main, source of discrepancies between different ionization models (and reality). Depending on the assumptions single ionization profiles may vary by a factor of 5, long-term calculations may show systematic over- or underestimation in specific altitudes and even for ideal setups the definition of the energy-range involves an intrinsic 25% uncertainty for the

Fuel from the synthesis gas - the role of process engineering

Energy Technology Data Exchange (ETDEWEB)

Stelmachowski, Marek; Nowicki, Lech [Technical Univ. of Lodz, Dept. of Environmental Engineering Systems, Lodz (Poland)

2003-02-01

The paper presents the conclusions obtained in the investigations of methanol synthesis, Fischer-Tropsch synthesis, and higher alcohols synthesis from syngas as a raw material in slurry reactors. The overview of the role of process engineering was made on the basis of the experience in optimizing process conditions, modeling reactors and working out new technologies. Experimental data, obtained with a laboratory-stirred autoclave and theoretical considerations were used to develop the kinetic models that can describe the product formation and the model of the simultaneous phase and chemical equilibrium for the methanol and Fischer-Tropsch syntheses in the slurry reactors. These models were employed in modeling of the bubble-column slurry reactor (BCSR). Based on these considerations, a computer simulation of the low-pressure methanol synthesis for the pilot-scale, BCSR, was devised. The results of the calculations and the conclusions could be employed in the process for designing an industrial plant. (Author)

Insight into the influence of liquid paraffin for methanol synthesis on Cu(110) surface using continuum and atomistic models

Energy Technology Data Exchange (ETDEWEB)

Jiao, Wei-Hong [Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province, Taiyuan University of Technology, Taiyuan 030024, Shanxi (China); Liu, Shi-Zhong [Department of Chemistry, Stony Brook University, Stony Brook, NY 11794 (United States); Zuo, Zhi-Jun, E-mail: zuozhijun@tyut.edu.cn [Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province, Taiyuan University of Technology, Taiyuan 030024, Shanxi (China); Ren, Rui-Peng; Gao, Zhi-Hua [Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province, Taiyuan University of Technology, Taiyuan 030024, Shanxi (China); Huang, Wei, E-mail: huangwei@tyut.edu.cn [Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province, Taiyuan University of Technology, Taiyuan 030024, Shanxi (China)

2016-11-30

Highlights: • The influence of liquid paraffin is studied using continuum and atomistic models. • Liquid paraffin does not alter the reaction pathways of CO hydrogenation and WGS. • Liquid paraffin alters the reaction pathways of CO{sub 2} hydrogenation. - Abstract: Methanol synthesis from CO/CO{sub 2} hydrogenation and water-gas shift (WGS) reaction on Cu(110) in liquid paraffin and vacuum have been systematically researched with density functional theory calculation (DFT). For methanol synthesis from CO hydrogenation, the reaction pathways in liquid paraffin and vacuum are CO + H → HCO → H{sub 2}CO → H{sub 3}CO → H{sub 3}COH; in the case of WGS, the reaction pathways in liquid paraffin and vacuum are CO + 2H{sub 2}O → CO + 2OH + 2H → CO + H{sub 2}O + O + H{sub 2} → CO{sub 2} + H{sub 2}O + H{sub 2}; the reaction pathways of methanol synthesis from CO{sub 2} hydrogenation in liquid paraffin and vacuum are CO{sub 2} + H → HCOO → H{sub 2}COO → H{sub 2}CO → H{sub 3}CO → H{sub 3}COH and CO{sub 2} + H → HCOO → HCOOH → H{sub 2}COOH → H{sub 3}CO → H{sub 3}COH, respectively. The result shows that liquid paraffin does not affect the reaction mechanisms of methanol synthesis from CO and WGS, but it changes the reaction mechanisms of methanol synthesis from CO{sub 2} hydrogenation. Hirshfeld charge and the d-band centers indicate that the catalytic activity of Cu(110) in liquid paraffin is smaller than that in vacuum. Our results also show that it is necessary to consider both continuum and atomistic models in the slurry bed.

Synthesis of vitamin D and erythemal irradiance obtained with a multiband filter radiometer and annual variation analysis in Río Gallegos, Argentina

Science.gov (United States)

Orte, P. F.; Wolfram, E. A.; Salvador, J.; D'Elia, R.; Paes Leme, N.; Quel, E. J.

2011-01-01

In this paper we examined the annual variability of the erythemal solar radiation (a health risk) and the solar irradiance for synthesis of vitamin D (a health benefit) in Río Gallegos, Argentina. We use ultraviolet radiation measurements made by a multiband filter radiometer GUV-541 and a Brewer spectrophotometer located at CEILAP-RG Station (CITEFA-CONICET) (51° 33' S, 69° 19' W). These measurements are weighted with action spectra published by the CIE (International Commission on Illumination). An action spectrum describes the relative effectiveness of different wavelengths in the generation of a particular biological response. The analyzed data correspond to September 2008-December 2009 period. The methodology used to obtain the erythemal irradiance and synthesis of vitamin D values combines irradiance measurements of a multiband filter radiometer with modeled values (output of radiative transfer model) and measurements of a Brewer spectrophotometer. This procedure increases the instrumental capabilities of this instrument. The synthesis of vitamin D and erythema are affected by UVB solar radiation. Therefore, its effect is strongly dependent of the stratospheric ozone amount, which undergoes large variations in the Río Gallegos city due to ozone hole passage and its influence on these sub-polar latitudes. We observed that could exist cases of sunburn for reasonable exposure in abnormal situations of low total ozone column, resulting in high levels of ultraviolet radiation. Furthermore, the synthesis of vitamin D through exposure to ultraviolet radiation would be lower than the appropriate values to the majority of the year for these latitudes. Therefore it is important to evaluate the annual variation of these quantities realizing seasonal balance between this health risk and this health benefit.

Synthesis of nanosilver on polyamide fabric using silver/ammonia complex

Energy Technology Data Exchange (ETDEWEB)

Montazer, Majid, E-mail: tex5mm@aut.ac.ir [Textile Department, Functional Fibrous Structures and Environmental Enhancement (FFSEE), Amirkabir University of Technology, Hafez Avenue, Tehran (Iran, Islamic Republic of); Shamei, Ali; Alimohammadi, Farbod [Young Researchers Club, Tehran South Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of)

2014-05-01

In this paper, a novel synthesis method for nanosilver has been introduced on or within the polymeric chains of polyamide 6 fabric by using silver/ammonia complex [Ag(NH{sub 3}){sub 2}]{sup +}. The silver complex was reduced directly by functional groups of polyamide chains without using any additional chemical reducing agents. The polyamide fabric was also stabilized with formation of new linkages between the polymeric chains of the nylon fabric through silver nanoparticle synthesis. The presence of nanosilver on the fabric was confirmed by UV–vis spectra, EDX patterns and XRD patterns. In addition, X-ray photoelectron spectroscopy (XPS) was utilized to identify the chemical state of silver in a range of silver oxide and silver metal. The SEM images confirmed the presence of nanosilver on the polyamide within the size of 20 and 150 nm. Excellent antibacterial properties were achieved with the treated fabrics against Staphylococcus aureus and Escherichia coli. Further, the antibacterial properties of the polyamide fabric treated with 35 mg/L silver/ammonia were durable against washing as they only decreased to 98.6% after 20 washes. In addition, some other properties of the treated fabrics including color changes, dimensional stability, water droplet adsorption, and reflectance spectrum are reported and thoroughly discussed. - Highlights: • Novel in situ synthesis of nanosilver on polyamide 6 • Synthesis of nanosilver without using external stabilizing and reducing agent • Synthesis of nanosilver particles within molecular chains of polyamide 6 • Producing antibacterial polyamide 6 using 35 mg/L Ag/ammonia complex • Obtaining durable antibacterial properties on polyamide 6 by this method.

Synthesis of nanosilver on polyamide fabric using silver/ammonia complex

International Nuclear Information System (INIS)

Montazer, Majid; Shamei, Ali; Alimohammadi, Farbod

2014-01-01

In this paper, a novel synthesis method for nanosilver has been introduced on or within the polymeric chains of polyamide 6 fabric by using silver/ammonia complex [Ag(NH 3 ) 2 ] + . The silver complex was reduced directly by functional groups of polyamide chains without using any additional chemical reducing agents. The polyamide fabric was also stabilized with formation of new linkages between the polymeric chains of the nylon fabric through silver nanoparticle synthesis. The presence of nanosilver on the fabric was confirmed by UV–vis spectra, EDX patterns and XRD patterns. In addition, X-ray photoelectron spectroscopy (XPS) was utilized to identify the chemical state of silver in a range of silver oxide and silver metal. The SEM images confirmed the presence of nanosilver on the polyamide within the size of 20 and 150 nm. Excellent antibacterial properties were achieved with the treated fabrics against Staphylococcus aureus and Escherichia coli. Further, the antibacterial properties of the polyamide fabric treated with 35 mg/L silver/ammonia were durable against washing as they only decreased to 98.6% after 20 washes. In addition, some other properties of the treated fabrics including color changes, dimensional stability, water droplet adsorption, and reflectance spectrum are reported and thoroughly discussed. - Highlights: • Novel in situ synthesis of nanosilver on polyamide 6 • Synthesis of nanosilver without using external stabilizing and reducing agent • Synthesis of nanosilver particles within molecular chains of polyamide 6 • Producing antibacterial polyamide 6 using 35 mg/L Ag/ammonia complex • Obtaining durable antibacterial properties on polyamide 6 by this method

Incident spectrum determination for time-of-flight neutron powder diffraction data analysis

International Nuclear Information System (INIS)

Hodges, J. P.

1998-01-01

Accurate characterization of the incident neutron spectrum is an important requirement for precise Rietveld analysis of time-of-flight powder neutron diffraction data. Without an accurate incident spectrum the calculated model for the measured relative intensities of individual Bragg reflections will possess systematic errors. We describe a method for obtaining an accurate numerical incident spectrum using data from a transmitted beam monitor

Introducing an Information-Seeking Skill in a School Library to Students with Autism Spectrum Disorder: Using Video Modeling and Least-to-Most Prompts

Science.gov (United States)

Markey, Patricia T.

2015-01-01

This study investigated the effectiveness of a video peer modeling and least-to-most prompting intervention in the school library setting, targeting the instructional delivery of an information-literacy skill to students with Autism Spectrum Disorder (ASD). Research studies have evaluated the effectiveness of video-modeling procedures in the…

An assessment of finite element synthesis model using 3D FEM

International Nuclear Information System (INIS)

Jagannathan, V.; Rastogi, B.P

1983-01-01

For the solution of multigroup diffusion theory equations a code system called FEMSYN has been developed. The code FEMSYN incorporates a finite difference (FD) module, a finite element (FE) module and one module based on single channel flux synthesis (SCFS) method, which uses trial functions generated by either FD or FE method. The 3D problems can be tackled by all the three modules. The 3D FE solutions are cheaper in comparison with fine mesh FD computations and are quite accurate. The accuracy is improved by proper choice of rectangular and triangular right prismatic elements and polynomial order in case of 3D FE analyses. Synthesis method using FE trial functions provides the fastest means of solution for 3D problems. In this paper, the FE synthesis method has been compared with 3D FE technique for the case of IAEA PWR benchmark problem. It is concluded from the above comparison that FE synthesis method can give at negligible computational efforts, accurate eigenvalue estimates and satisfactory prediction of reactor core power profiles

Parametric Hidden Markov Models for Recognition and Synthesis of Movements

DEFF Research Database (Denmark)

Herzog, Dennis; Krüger, Volker; Grest, Daniel

2008-01-01

In humanoid robotics, the recognition and synthesis of parametric movements plays an extraordinary role for robot human interaction. Such a parametric movement is a movement of a particular type (semantic), for example, similar pointing movements performed at different table-top positions....... For understanding the whole meaning of a movement of a human, the recognition of its type, likewise its parameterization are important. Only both together convey the whole meaning. Vice versa, for mimicry, the synthesis of movements for the motor control of a robot needs to be parameterized, e.g., by the relative...... the applicability for online recognition based on very noisy 3D tracking data. The use of a parametric representation of movements is shown in a robot demo, where a robot removes objects from a table as demonstrated by an advisor. The synthesis for motor control is performed for arbitrary table-top positions....

Warped Linear Prediction of Physical Model Excitations with Applications in Audio Compression and Instrument Synthesis

Science.gov (United States)

Glass, Alexis; Fukudome, Kimitoshi

2004-12-01

A sound recording of a plucked string instrument is encoded and resynthesized using two stages of prediction. In the first stage of prediction, a simple physical model of a plucked string is estimated and the instrument excitation is obtained. The second stage of prediction compensates for the simplicity of the model in the first stage by encoding either the instrument excitation or the model error using warped linear prediction. These two methods of compensation are compared with each other, and to the case of single-stage warped linear prediction, adjustments are introduced, and their applications to instrument synthesis and MPEG4's audio compression within the structured audio format are discussed.

PHAST- a spectrum stabilising PC-MCA

International Nuclear Information System (INIS)

Mukhopadhyay, P.K.; Satish, P.; Shrivastava, V.D.

2001-01-01

Model PHAST, a PC-card with programmable features, incorporates a 100 MHz Wilkinson ADC with conversion gain of 8K. It also provides SCA mode MCS operation. The card caters to the needs of precision nuclear spectroscopy at low to moderate count rates. Spectrum drift may be eliminated by spectrum stabilisation. Proper dead time correction is achieved by Gedcke-Hale or pulse generator based schemes. Multiple cards may be operated together in a single PC in independent operating modes. These cards have onboard histogram memory and updating mechanism. Hence they will usually continue to acquire data in the event of a system crash. (author)

Reducing Maladaptive Behaviors in Preschool-Aged Children with Autism Spectrum Disorder Using the Early Start Denver Model

OpenAIRE

Fulton, Elizabeth; Eapen, Valsamma; Črnčec, Rudi; Walter, Amelia; Rogers, Sally

2014-01-01

The presence of maladaptive behaviors in young people with autism spectrum disorder (ASD) can significantly limit engagement in treatment programs, as well as compromise future educational and vocational opportunities. This study aimed to explore whether the Early Start Denver Model (ESDM) treatment approach reduced maladaptive behaviors in preschool-aged children with ASD in a community-based long day care setting. The level of maladaptive behavior of 38 children with ASD was rated using an ...

Reducing maladaptive behaviors in preschool-aged children with Autism Spectrum Disorder using the Early Start Denver Model

OpenAIRE

Elizabeth eFulton; Elizabeth eFulton; Valsamma eEapen; Valsamma eEapen; Rudi eČrnčec; Amelia eWalter; Amelia eWalter; Sally eRogers

2014-01-01

The presence of maladaptive behaviors in young people with Autism Spectrum Disorder (ASD) can significantly limit engagement in treatment programs, as well as compromise future educational and vocational opportunities. This study aimed to explore whether the Early Start Denver Model (ESDM) treatment approach reduced maladaptive behaviors in preschool-aged children with ASD in a community-based long day care setting. The level of maladaptive behavior of 38 children with ASD was rated using an ...

Spectrum Recombination.

Science.gov (United States)

Greenslade, Thomas B., Jr.

1984-01-01

Describes several methods of executing lecture demonstrations involving the recombination of the spectrum. Groups the techniques into two general classes: bringing selected portions of the spectrum together using lenses or mirrors and blurring the colors by rapid movement or foreshortening. (JM)

Synthesis of superheavy elements: Uncertainty analysis to improve the predictive power of reaction models

OpenAIRE

Lu , H.; Boilley , D.; Abe , Y.; Shen , C.

2016-01-01

13 pages, 13 figures, submitted for publication in PRC; International audience; Background: Synthesis of super-heavy elements is performed by heavy-ion fusion-evaporation reactions. However , fusion is known to be hindered with respect to what can be observed with lighter ions. Thus some delicate ambiguities remain on the fusion mechanism that eventually lead to severe discrepancies in the calculated formation probabilities coming from different fusion models. Purpose: In the present work, we...

Bottomonia: open bottom strong decays and spectrum

Directory of Open Access Journals (Sweden)

Santopinto E.

2014-05-01

Full Text Available We present our results for the bottomonium spectrum with self energy corrections. The bare masses used in the calculation are computed within Godfrey and Isgur’s relativized quark model. We also discuss our results for the open bottom strong decay widths of higher bottomonia in the 3P0 pair-creation model.

Synaptic Synthesis, Dephosphorylation, and Degradation

Science.gov (United States)

La Montanara, Paolo; Rusconi, Laura; Locarno, Albina; Forti, Lia; Barbiero, Isabella; Tramarin, Marco; Chandola, Chetan; Kilstrup-Nielsen, Charlotte; Landsberger, Nicoletta

2015-01-01

Mutations in the X-linked CDKL5 (cyclin-dependent kinase-like 5) gene have been associated with several forms of neurodevelopmental disorders, including atypical Rett syndrome, autism spectrum disorders, and early infantile epileptic encephalopathy. Accordingly, loss of CDKL5 in mice results in autistic-like features and impaired neuronal communication. Although the biological functions of CDKL5 remain largely unknown, recent pieces of evidence suggest that CDKL5 is involved in neuronal plasticity. Herein, we show that, at all stages of development, neuronal depolarization induces a rapid increase in CDKL5 levels, mostly mediated by extrasomatic synthesis. In young neurons, this induction is prolonged, whereas in more mature neurons, NMDA receptor stimulation induces a protein phosphatase 1-dependent dephosphorylation of CDKL5 that is mandatory for its proteasome-dependent degradation. As a corollary, neuronal activity leads to a prolonged induction of CDKL5 levels in immature neurons but to a short lasting increase of the kinase in mature neurons. Recent results demonstrate that many genes associated with autism spectrum disorders are crucial components of the activity-dependent signaling networks regulating the composition, shape, and strength of the synapse. Thus, we speculate that CDKL5 deficiency disrupts activity-dependent signaling and the consequent synapse development, maturation, and refinement. PMID:25555910

Evidence for the Implementation of the Early Start Denver Model for Young Children With Autism Spectrum Disorder.

Science.gov (United States)

Ryberg, Kayce H

2015-01-01

The Early Start Denver Model (ESDM) is a manualized comprehensive therapy for toddlers with autism spectrum disorder. It emphasizes interpersonal engagement through synchrony, rhythms, and reciprocity to decrease symptom severity and accelerate cognitive, social-emotional, and language development. To systematically review evidence regarding the use of the ESDM as an intervention for young children with autism spectrum disorder. PubMed, Scopus, Web of Science, Embase, and CINAHL were searched from 2010-2015 using predetermined inclusion criteria. Study methodology, participant characteristics, and outcomes were evaluated and quality of evidence was assigned. Eight articles met inclusion criteria and consisted of two randomized controlled trials, four controlled trials, and two observational cohort studies. Evidence quality ranged from low to high. The ESDM is an effective intervention that improves cognition, language, and adaptive behavior. ESDM strategies delivered in community group settings and in the home by parents have potential to be efficacious and feasible. © The Author(s) 2015.

A ground-based optical transmission spectrum of WASP-6b

International Nuclear Information System (INIS)

Jordán, Andrés; Espinoza, Néstor; Rabus, Markus; Eyheramendy, Susana; Sing, David K.; Désert, Jean-Michel; Bakos, Gáspár Á.; Fortney, Jonathan J.; López-Morales, Mercedes; Szentgyorgyi, Andrew; Maxted, Pierre F. L.; Triaud, Amaury H. M. J.

2013-01-01

We present a ground-based optical transmission spectrum of the inflated sub-Jupiter-mass planet WASP-6b. The spectrum was measured in 20 spectral channels from 480 nm to 860 nm using a series of 91 spectra over a complete transit event. The observations were carried out using multi-object differential spectrophotometry with the Inamori-Magellan Areal Camera and Spectrograph on the Baade Telescope at Las Campanas Observatory. We model systematic effects on the observed light curves using principal component analysis on the comparison stars and allow for the presence of short and long memory correlation structure in our Monte Carlo Markov Chain analysis of the transit light curves for WASP-6. The measured transmission spectrum presents a general trend of decreasing apparent planetary size with wavelength and lacks evidence for broad spectral features of Na and K predicted by clear atmosphere models. The spectrum is consistent with that expected for scattering that is more efficient in the blue, as could be caused by hazes or condensates in the atmosphere of WASP-6b. WASP-6b therefore appears to be yet another massive exoplanet with evidence for a mostly featureless transmission spectrum, underscoring the importance that hazes and condensates can have in determining the transmission spectra of exoplanets.

REMOTE SYNTHESIS AND CONTROL INFORMATION TECHNOLOGY OF SYSTEM-DYNAMIC MODELS

Directory of Open Access Journals (Sweden)

A. V. Masloboev

2015-07-01

Full Text Available The general line of research is concerned with development of information technologies and computer simulation tools for management information and analytical support of complex semistructured systems. Regional socio-economic systems are consideredas a representative of this system type. Investigation is carried out within the bounds of development strategy implementation of the Arctic zone of the Russian Federation and national safety until 2020 in the Murmansk region, specifically under engineering of high end information infrastructure for innovation and security control problem-solving of regional development. Research methodology consists of system dynamics modeling method, distributed information system engineering technologies, pattern-based modeling and design techniques. The work deals with development of toolkit for decision-making information support problem-solving in the field of innovation security management of regional economics. For that purpose a system-dynamic models suite of innovation process standard components and information technology for remote formation and control of innovation business simulation models under research have been developed. Designed toolkit provides innovation security index dynamics forecasting and innovation business effectiveness of regional economics. Information technology is implemented within the bounds of thin client architecture and is intended for simulation models design process automation of complex systems. Technology implementation software tools provide pattern-based system-dynamic models distributed formation and simulation control of innovation processes. The technology provides availability and reusability index enhancement of information support facilities in application to innovation process simulation at the expense of distributed access to innovation business simulation modeling tools and model synthesis by the reusable components, simulating standard elements of innovation

Nonlinear evolution of the matter power spectrum in modified theories of gravity

International Nuclear Information System (INIS)

Koyama, Kazuya; Taruya, Atsushi; Hiramatsu, Takashi

2009-01-01

We present a formalism to calculate the nonlinear matter power spectrum in modified gravity models that explain the late-time acceleration of the Universe without dark energy. Any successful modified gravity models should contain a mechanism to recover general relativity (GR) on small scales in order to avoid the stringent constrains on deviations from GR at solar system scales. Based on our formalism, the quasi-nonlinear power spectrum in the Dvali-Gabadadze-Porratti braneworld models and f(R) gravity models are derived by taking into account the mechanism to recover GR properly. We also extrapolate our predictions to fully nonlinear scales using the parametrized post-Friedmann framework. In the Dvali-Gabadadze-Porratti and f(R) gravity models, the predicted nonlinear power spectrum is shown to reproduce N-body results. We find that the mechanism to recover GR suppresses the difference between the modified gravity models and dark energy models with the same expansion history, but the difference remains large at the weakly nonlinear regime in these models. Our formalism is applicable to a wide variety of modified gravity models and it is ready to use once consistent models for modified gravity are developed.

Tropical Hydroclimate Change during Heinrich Stadial 1: An Integrative Proxy-Model Synthesis

Science.gov (United States)

Lawman, A. E.; Sun, T.; Shanahan, T. M.; Di Nezio, P. N.; Gomez, K.; Piatrunia, N.; Sun, C.; Wu, X.; Kageyama, M.; Merkel, U.; Otto-Bliesner, B. L.; Abe-Ouchi, A.; Lohmann, G.; Singarayer, J. S.

2017-12-01

We explore the response of tropical climate to abrupt cooling of the North Atlantic (NA) during Heinrich Stadial 1 (HS1) combining paleoclimate proxies with model simulations. A total of 146 published paleoclimate records from tropical locations are used to categorize whether HS1 was wetter, drier, or unchanged relative to a deglacial baseline state. Only records with sufficient resolution to resolve HS1 and sufficient length to characterize the deglacial trend are considered. This synthesis reveals large-scale patterns of hydroclimate change relative to glacial conditions, confirming previously reported weaker Indian summer monsoon, a wetter southern Africa, and drying over the Caribbean. Our synthesis also reveals large-scale drying over the Maritime continent as well as wetter conditions in northern Australia and southern tropical South America. Our reinterpretation of the available proxy data reveals far more complexity and uncertainties for equatorial East Africa, a region that appears to straddle a pattern of dryer conditions to the north and wetter conditions to the south. Overall, these patterns of hydroclimate change depart from a southward shift of the Inter Tropical Convergence Zone (ITCZ), particularly outside the tropical Atlantic. We explore mechanisms driving these changes using a multi-model ensemble of "hosing" simulations performed relative to glacial conditions. The models show robust weakening of the Afro-Asian Monsoon, which we attribute to ventilation of colder mid-latitude air. Not all models simulate the remaining patterns inferred from the proxy data. The best-agreeing models indicate that cooling over the tropical NA and the Caribbean may be essential to communicate the response to the global tropics. This response can induce warming over the tropical South Atlantic via the wind-evaporation-SST feedback, driving wetter conditions in South Africa and tropical South America. Cooling over the Caribbean is communicated to the Pacific over the

The synthesis and physiological activity of 2,3,4,5-tetrahydro-1H-pyrido[4,3-b]indoles

International Nuclear Information System (INIS)

Ivashchenko, A V; Mitkin, O D; Kadieva, M G; Tkachenko, S E

2010-01-01

Data on the methods of 2,3,4,5-tetrahydro-1H-pyrido[4,3-b]indoles synthesis has been surveyed. The synthetic accessibility of various derivatives of these heterocycles has been demonstrated. It has been shown that such compounds exhibit a broad spectrum of pharmacological activity and hold interest for medicinal chemistry.

Video Self-Modeling Interventions for Students with Autism Spectrum Disorder

Science.gov (United States)

Schaeffer, Kathleen M.; Hamilton, Kendra A.; Bauman Johnson, Wendi L.

2016-01-01

Implementing evidenced-based interventions for students with autism spectrum disorder (ASD) in the educational setting is of utmost importance for their long-term success. Unfortunately, interventions often are not implemented with efficacy due to the overwhelming demands on educators attempting to meet the individualized needs of each student.…

A mechano-chemiosmotic model for the coupling of electron and proton transfer to ATP synthesis in energy-transforming membranes: a personal perspective.

Science.gov (United States)

Kasumov, Eldar A; Kasumov, Ruslan E; Kasumova, Irina V

2015-01-01

ATP is synthesized using ATP synthase by utilizing energy either from the oxidation of organic compounds, or from light, via redox reactions (oxidative- or photo phosphorylation), in energy-transforming membranes of mitochondria, chloroplasts, and bacteria. ATP synthase undergoes several changes during its functioning. The generally accepted model for ATP synthesis is the well-known rotatory model (see e.g., Junge et al., Nature 459:364-370, 2009; Junge and Müller, Science 333:704-705, 2011). Here, we present an alternative modified model for the coupling of electron and proton transfer to ATP synthesis, which was initially developed by Albert Lester Lehninger (1917-1986). Details of the molecular mechanism of ATP synthesis are described here that involves cyclic low-amplitude shrinkage and swelling of mitochondria. A comparison of the well-known current model and the mechano-chemiosmotic model is also presented. Based on structural, and other data, we suggest that ATP synthase is a Ca(2+)/H(+)-K(+) Cl(-)-pump-pore-enzyme complex, in which γ-subunit rotates 360° in steps of 30°, and 90° due to the binding of phosphate ions to positively charged amino acid residues in the N-terminal γ-subunit, while in the electric field. The coiled coil b 2-subunits are suggested to act as ropes that are shortened by binding of phosphate ions to positively charged lysines or arginines; this process is suggested to pull the α 3 β 3-hexamer to the membrane during the energization process. ATP is then synthesized during the reverse rotation of the γ-subunit by destabilizing the phosphated N-terminal γ-subunit and b 2-subunits under the influence of Ca(2+) ions, which are pumped over from storage-intermembrane space into the matrix, during swelling of intermembrane space. In the process of ATP synthesis, energy is first, predominantly, used in the delivery of phosphate ions and protons to the α 3 β 3-hexamer against the energy barrier with the help of C-terminal alpha

GalMod: the last frontier of Galaxy population synthesis models

Science.gov (United States)

Pasetto, Stefano; Kollmeier, Juna; Grebel, Eva K.; chiosi, cesare

2018-01-01

We present a novel Galaxy population synthesis model: GalMod (Pasetto et al. 2016, 2017a,b) is the only star-count model featuring an asymmetric bar/bulge as well as spiral arms as directly obtained by applying linear perturbative theory to self-consistent distribution function of the Galaxy stellar populations. Compared to previous literature models (e.g., Besancon, Trilegal), GalMod allows to generate full-sky mock catalogue, M31 surveys and provides a better match to observed Milky Way (MW) stellar fields.The model can generate synthetic mock catalogs of visible portions of the MW, external galaxies like M31, or N-body simulation initial conditions. At any given time, e.g., a chosen age of the Galaxy, the model contains a sum of discrete stellar populations, namely bulge/bar, disk, halo. The disk population is itself the sum of subpopulations: spiral arms, thin disk, thick disk, and gas component, while the halo is modeled as the sum of a stellar component, a hot coronal gas, and a dark matter component. The Galactic potential is computed from these subpopulations' density profiles and used to generate detailed kinematics by considering the first few moments of the Boltzmann collisionless equation for all the stellar subpopulations. The same density profiles are then used to define the observed color-magnitude diagrams within an input field of view from an arbitrary solar location. Several photometric systems have been included and made available on-line, e.g., SDSS, Gaia, 2MASS, HST WFC3, and others. Finally, we model the extinction with advanced ray tracing solutions.The model's web page (and tutorial) can be accessed at www.GalMod.org.

Using near infrared spectrum analysis to predict water and chlorophyll content in tomato leaves

Science.gov (United States)

Jiang, Huanyu; Ying, Yibin; Liu, Yande

2004-11-01

In this study, we developed a nondestructive way to analyze water and chlorophyll content in tomato leaves. A total of 200 leaves were collected as experimental materials, 120 of them were used to form a calibration data set. Drying chest, SPAD meter and NIR spectrometer were used to get water content, chlorophyll content and spectrums of tomato leaves respectively. The Fourier Transform Infrared (FTNIR) method with a smart Near-IR Updrift was used to test spectrums, and partial least squares (PLS) technique was used to analyze the data we get by normal experimentation and near infrared spectrometer, set up a calibration model to predict the leaf water and chlorophyll content based on the characteristics of diffuse reflectance spectrums of tomato leaves. Three different mathematical treatments were used in spectrums processing: different wavelength range, different smoothing points, first and second derivative. We can get best prediction model when we select full range (800-2500nm), 3 points for spectrums smoothing and spectrums by baseline correction, the best model of chlorophyll content has a root mean square error of prediction (RMSEP) of 8.16 and a calibration correlation coefficient (R2) value of 0.89452 and the best model of water content has a root mean square error of prediction (RMSEP) of 0.0214 and a calibration correlation coefficient (R2) value of 0.91043.

A Clinical Translation of the Article Titled "Evidence for the Implementation of the Early Start Denver Model for Young Children With Autism Spectrum Disorder".

Science.gov (United States)

Shannon, Robin Adair

2015-01-01

The purpose of this article is to offer a clinical translation of a literature review titled "Evidence for the Implementation of the Early Start Denver Model for Young Children With Autism Spectrum Disorder" by Ryberg (2015). The literature review was conducted to determine the strength of the research evidence regarding the effectiveness of the Early Start Denver Model in improving cognitive, language, and behavioral functioning of children with autism spectrum disorder. In an effort to narrow the gap between evidence and practice, this clinical translation will discuss the components of the literature review in terms of its rationale for and objectives, methods, results, and implications for evidence-based nursing practice. © The Author(s) 2015.

The Role of Nice and Nasty Theory of Mind in Teacher-Selected Peer Models for Adolescents with Autism Spectrum Disorders

Science.gov (United States)

Laghi, Fiorenzo; Lonigro, Antonia; Levanto, Simona; Ferraro, Maurizio; Baumgartner, Emma; Baiocco, Roberto

2016-01-01

The study aimed at verifying if nice and nasty theory of mind behaviors, in association with teachers' peer buddy nomination, could be used to correctly select peer models for adolescents with autism spectrum disorder. Mentalizing abilities and emotional and behavioral characteristics of 601 adolescents were assessed. Results suggest that teachers…

Comparison of spectrum normalization techniques for univariate ...

Indian Academy of Sciences (India)

Laser-induced breakdown spectroscopy; univariate study; normalization models; stainless steel; standard error of prediction. Abstract. Analytical performance of six different spectrum normalization techniques, namelyinternal normalization, normalization with total light, normalization with background along with their ...

Homeostatic mechanisms in dopamine synthesis and release: a mathematical model

Directory of Open Access Journals (Sweden)

Nijhout H Frederik

2009-09-01

Full Text Available Abstract Background Dopamine is a catecholamine that is used as a neurotransmitter both in the periphery and in the central nervous system. Dysfunction in various dopaminergic systems is known to be associated with various disorders, including schizophrenia, Parkinson's disease, and Tourette's syndrome. Furthermore, microdialysis studies have shown that addictive drugs increase extracellular dopamine and brain imaging has shown a correlation between euphoria and psycho-stimulant-induced increases in extracellular dopamine 1. These consequences of dopamine dysfunction indicate the importance of maintaining dopamine functionality through homeostatic mechanisms that have been attributed to the delicate balance between synthesis, storage, release, metabolism, and reuptake. Methods We construct a mathematical model of dopamine synthesis, release, and reuptake and use it to study homeostasis in single dopaminergic neuron terminals. We investigate the substrate inhibition of tyrosine hydroxylase by tyrosine, the consequences of the rapid uptake of extracellular dopamine by the dopamine transporters, and the effects of the autoreceoptors on dopaminergic function. The main focus is to understand the regulation and control of synthesis and release and to explicate and interpret experimental findings. Results We show that the substrate inhibition of tyrosine hydroxylase by tyrosine stabilizes cytosolic and vesicular dopamine against changes in tyrosine availability due to meals. We find that the autoreceptors dampen the fluctuations in extracellular dopamine caused by changes in tyrosine hydroxylase expression and changes in the rate of firing. We show that short bursts of action potentials create significant dopamine signals against the background of tonic firing. We explain the observed time courses of extracellular dopamine responses to stimulation in wild type mice and mice that have genetically altered dopamine transporter densities and the observed

Critical excitation spectrum of a quantum chain with a local three-spin coupling.

Science.gov (United States)

McCabe, John F; Wydro, Tomasz

2011-09-01

Using the phenomenological renormalization group (PRG), we evaluate the low-energy excitation spectrum along the critical line of a quantum spin chain having a local interaction between three Ising spins and longitudinal and transverse magnetic fields, i.e., a Turban model. The low-energy excitation spectrum found with the PRG agrees with the spectrum predicted for the (D(4),A(4)) conformal minimal model under a nontrivial correspondence between translations at the critical line and discrete lattice translations. Under this correspondence, the measurements confirm a prediction that the critical line of this quantum spin chain and the critical point of the two-dimensional three-state Potts model are in the same universality class.

Critical excitation spectrum of a quantum chain with a local three-spin coupling

International Nuclear Information System (INIS)

McCabe, John F.; Wydro, Tomasz

2011-01-01

Using the phenomenological renormalization group (PRG), we evaluate the low-energy excitation spectrum along the critical line of a quantum spin chain having a local interaction between three Ising spins and longitudinal and transverse magnetic fields, i.e., a Turban model. The low-energy excitation spectrum found with the PRG agrees with the spectrum predicted for the (D 4 ,A 4 ) conformal minimal model under a nontrivial correspondence between translations at the critical line and discrete lattice translations. Under this correspondence, the measurements confirm a prediction that the critical line of this quantum spin chain and the critical point of the two-dimensional three-state Potts model are in the same universality class.

Two-component scattering model and the electron density spectrum

Science.gov (United States)

Zhou, A. Z.; Tan, J. Y.; Esamdin, A.; Wu, X. J.

2010-02-01

In this paper, we discuss a rigorous treatment of the refractive scintillation caused by a two-component interstellar scattering medium and a Kolmogorov form of density spectrum. It is assumed that the interstellar scattering medium is composed of a thin-screen interstellar medium (ISM) and an extended interstellar medium. We consider the case that the scattering of the thin screen concentrates in a thin layer represented by a δ function distribution and that the scattering density of the extended irregular medium satisfies the Gaussian distribution. We investigate and develop equations for the flux density structure function corresponding to this two-component ISM geometry in the scattering density distribution and compare our result with the observations. We conclude that the refractive scintillation caused by this two-component ISM scattering gives a more satisfactory explanation for the observed flux density variation than does the single extended medium model. The level of refractive scintillation is strongly sensitive to the distribution of scattering material along the line of sight (LOS). The theoretical modulation indices are comparatively less sensitive to the scattering strength of the thin-screen medium, but they critically depend on the distance from the observer to the thin screen. The logarithmic slope of the structure function is sensitive to the scattering strength of the thin-screen medium, but is relatively insensitive to the thin-screen location. Therefore, the proposed model can be applied to interpret the structure functions of flux density observed in pulsar PSR B2111 + 46 and PSR B0136 + 57. The result suggests that the medium consists of a discontinuous distribution of plasma turbulence embedded in the interstellar medium. Thus our work provides some insight into the distribution of the scattering along the LOS to the pulsar PSR B2111 + 46 and PSR B0136 + 57.

Relating the bipolar spectrum to dysregulation of behavioural activation: a perspective from dynamical modelling.

Science.gov (United States)

Steinacher, Arno; Wright, Kim A

2013-01-01

Bipolar Disorders affect a substantial minority of the population and result in significant personal, social and economic costs. Understanding of the causes of, and consequently the most effective interventions for, this condition is an area requiring development. Drawing upon theories of Bipolar Disorder that propose the condition to be underpinned by dysregulation of systems governing behavioural activation or approach motivation, we present a mathematical model of the regulation of behavioural activation. The model is informed by non-linear, dynamical principles and as such proposes that the transition from "non-bipolar" to "bipolar" diagnostic status corresponds to a switch from mono- to multistability of behavioural activation level, rather than an increase in oscillation of mood. Consistent with descriptions of the behavioural activation or approach system in the literature, auto-activation and auto-inhibitory feedback is inherent within our model. Comparison between our model and empirical, observational data reveals that by increasing the non-linearity dimension in our model, important features of Bipolar Spectrum disorders are reproduced. Analysis from stochastic simulation of the system reveals the role of noise in behavioural activation regulation and indicates that an increase of nonlinearity promotes noise to jump scales from small fluctuations of activation levels to longer lasting, but less variable episodes. We conclude that further research is required to relate parameters of our model to key behavioural and biological variables observed in Bipolar Disorder.

Cry, Baby, Cry: Expression of Distress As a Biomarker and Modulator in Autism Spectrum Disorder

OpenAIRE

Esposito, Gianluca; Hiroi, Noboru; Scattoni, Maria Luisa

2017-01-01

Abstract Background: Early diagnosis of autism spectrum disorder is critical, because early intensive treatment greatly improves its prognosis. Methods: We review studies that examined vocalizations of infants with autism spectrum disorder and mouse models of autism spectrum disorder as a potential means to identify autism spectrum disorder before the symptomatic elements of autism spectrum disorder emerge. We further discuss clinical implications and future research priorities in the field. ...

Analysis of neutron spectrum effects on primary damage in tritium breeding blankets

Energy Technology Data Exchange (ETDEWEB)

Choi, Yong Hee, E-mail: cyh871@snu.ac.kr [School of Energy Systems Engineering, Seoul National University, 599 Gwanak-ro, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Joo, Han Gyu [School of Energy Systems Engineering, Seoul National University, 599 Gwanak-ro, Gwanak-gu, Seoul 151-744 (Korea, Republic of)

2012-07-15

The effect of neutron spectrum on primary damages in a structural material of a tritium breeding blanket is investigated with a newly established recoil spectrum estimation system. First, a recoil spectrum generation code is developed to obtain the energy spectrum of primary knock-on atoms (PKAs) for a given neutron spectrum utilizing the latest ENDF/B data. Secondly, a method for approximating the high energy tail of the recoil spectrum is introduced to avoid expensive molecular dynamics calculations for high energy PKAs using the concept of recoil energy of the secondary knock-on atoms originated by the INtegration of CAScades (INCAS) model. Thirdly, the modified spectrum is combined with a set of molecular dynamics calculation results to estimate the primary damage parameters such as the number of surviving point defects. Finally, the neutron spectrum is varied by changing the material of the spectral shifter and the result in primary damage parameters is examined.

Analysis of neutron spectrum effects on primary damage in tritium breeding blankets

Science.gov (United States)

Choi, Yong Hee; Joo, Han Gyu

2012-07-01

The effect of neutron spectrum on primary damages in a structural material of a tritium breeding blanket is investigated with a newly established recoil spectrum estimation system. First, a recoil spectrum generation code is developed to obtain the energy spectrum of primary knock-on atoms (PKAs) for a given neutron spectrum utilizing the latest ENDF/B data. Secondly, a method for approximating the high energy tail of the recoil spectrum is introduced to avoid expensive molecular dynamics calculations for high energy PKAs using the concept of recoil energy of the secondary knock-on atoms originated by the INtegration of CAScades (INCAS) model. Thirdly, the modified spectrum is combined with a set of molecular dynamics calculation results to estimate the primary damage parameters such as the number of surviving point defects. Finally, the neutron spectrum is varied by changing the material of the spectral shifter and the result in primary damage parameters is examined.

Holding-time-aware asymmetric spectrum allocation in virtual optical networks

Science.gov (United States)

Lyu, Chunjian; Li, Hui; Liu, Yuze; Ji, Yuefeng

2017-10-01

Virtual optical networks (VONs) have been considered as a promising solution to support current high-capacity dynamic traffic and achieve rapid applications deployment. Since most of the network services (e.g., high-definition video service, cloud computing, distributed storage) in VONs are provisioned by dedicated data centers, needing different amount of bandwidth resources in both directions, the network traffic is mostly asymmetric. The common strategy, symmetric provisioning of traffic in optical networks, leads to a waste of spectrum resources in such traffic patterns. In this paper, we design a holding-time-aware asymmetric spectrum allocation module based on SDON architecture and an asymmetric spectrum allocation algorithm based on the module is proposed. For the purpose of reducing spectrum resources' waste, the algorithm attempts to reallocate the idle unidirectional spectrum slots in VONs, which are generated due to the asymmetry of services' bidirectional bandwidth. This part of resources can be exploited by other requests, such as short-time non-VON requests. We also introduce a two-dimensional asymmetric resource model for maintaining idle spectrum resources information of VON in spectrum and time domains. Moreover, a simulation is designed to evaluate the performance of the proposed algorithm, and results show that our proposed asymmetric spectrum allocation algorithm can improve the resource waste and reduce blocking probability.

Synthesis Reasoning and Its Application in Chinese Calligraphy Generation

Institute of Scientific and Technical Information of China (English)

XUSong-Hua; PANYun-He; ZHUANGYue-Ting; FRANCISC.M.Lau

2005-01-01

In this paper, we address the demanding task of developing intelligent systems equipped with machine creativity that can perform design tasks automatically. The main challenge is how to model human beings' creativity mathematically and mimic such creativity computationally. We propose a “synthesis reasoning model” as the underlying mechanism to simulate human beings’ creative thinking when they are handling design tasks. We present the theory of the synthesis reasoning model, and the detailed procedure of designing an intelligent system based on the model.We offer a case study of an intelligent Chinese calligraphy generation system which we have developed.Based on implementation experiences of the calligraphy generation system as well as a few other systems for solving real-world problems, we suggest a generic methodology for constructing intelligent systems using the synthesis reasoning model.

Study of U235 neutron fission spectrum by the knowledge of cross sections average over that spectrum

International Nuclear Information System (INIS)

Suarez, P.M.

1997-01-01

A literature search of cross sections averaged over the fission neutron spectrum confirms inconsistencies between calculated and experimental values for high threshold reactions. Since, in this case, calculated averaged cross sections are systematically lower than measured values, it is concluded that the representations used to carry out these calculations underestimate the number of neutrons in the high energy region of the spectrum. A careful measurement of the averaged cross section for the 45 Sc(n,2n) 44g Sc and 45 Sc(n,2n) 44m Sc high threshold reactions had been performed in the RA-6 Neutron Activation Analysis Laboratory after carefully checking that the neutron flux at the core position where the samples were being irradiated was indeed an undisturbed fission spectrum. The experimental values are greater than those calculated with either, Watt type representations or the one based on the Madland and Nix model for the prompt fission spectrum. In many areas of nuclear engineering, like validation of nuclear data, reactor calculations, applied nuclear physics, shielding design, etc., it is of great practical importance to have a representation for the neutron flux that can be expressed in a closed analytical form and that agrees with experimental results, specially for the most widely fissile nuclide, 235 U. The results of the calculations mentioned above lead us to propose an analytical form for the 235 U fission neutron spectrum that better agrees with experimental results in the whole energy spectrum. We propose two different forms; both are a modification of the Watt-type form that has been adopted within the ENDF/B-V files. One of the new analytical representations is defined in two regions: below 9.5 MeV it is exactly the same formula as that used within the ENDF/B-V files, above this energy the parameters of this formula are changed. The other proposed analytical representation is expressed by a single formula in the whole energy range. These two new

A Novel Spectrum Scheduling Scheme with Ant Colony Optimization Algorithm

Directory of Open Access Journals (Sweden)

Liping Liu

2018-01-01

Full Text Available Cognitive radio is a promising technology for improving spectrum utilization, which allows cognitive users access to the licensed spectrum while primary users are absent. In this paper, we design a resource allocation framework based on graph theory for spectrum assignment in cognitive radio networks. The framework takes into account the constraints that interference for primary users and possible collision among cognitive users. Based on the proposed model, we formulate a system utility function to maximize the system benefit. Based on the proposed model and objective problem, we design an improved ant colony optimization algorithm (IACO from two aspects: first, we introduce differential evolution (DE process to accelerate convergence speed by monitoring mechanism; then we design a variable neighborhood search (VNS process to avoid the algorithm falling into the local optimal. Simulation results demonstrate that the improved algorithm achieves better performance.

Procedures and Compliance of a Video Modeling Applied Behavior Analysis Intervention for Brazilian Parents of Children with Autism Spectrum Disorders

Science.gov (United States)

Bagaiolo, Leila F.; Mari, Jair de J.; Bordini, Daniela; Ribeiro, Tatiane C.; Martone, Maria Carolina C.; Caetano, Sheila C.; Brunoni, Decio; Brentani, Helena; Paula, Cristiane S.

2017-01-01

Video modeling using applied behavior analysis techniques is one of the most promising and cost-effective ways to improve social skills for parents with autism spectrum disorder children. The main objectives were: (1) To elaborate/describe videos to improve eye contact and joint attention, and to decrease disruptive behaviors of autism spectrum…

Spectrums Transform Operators in Bases of Fourier and Walsh Functions

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V. V. Syuzev

2017-01-01

Full Text Available The problems of synthesis of the efficient algorithms for digital processing of discrete signals require transforming the signal spectra from one basis system into other. The rational solution to this problem is to construct the Fourier kernel, which is a spectrum of some basis functions, according to the system of functions of the other basis. However, Fourier kernel properties are not equally studied and described for all basis systems of practical importance. The article sets a task and presents an original way to solve the problem of mutual transformation of trigonometric Fourier spectrum into Walsh spectrum of different basis systems.The relevance of this theoretical and applied problem is stipulated, on the one hand, by the prevalence of trigonometric Fourier basis for harmonic representation of digital signals, and, on the other hand, by the fact that Walsh basis systems allow us to have efficient algorithms to simulate signals. The problem solution is achieved through building the Fourier kernel of a special structure that allows us to establish independent groups of Fourier and Walsh spectrum coefficients for further reducing the computational complexity of the transform algorithms.The article analyzes the properties of the system of trigonometric Fourier functions and shows its completeness. Considers the Walsh function basis systems in three versions, namely those of Hadamard, Paley, and Hartmut giving different ordering and analytical descriptions of the functions that make up the basis. Proves a completeness of these systems.Sequentially, for each of the three Walsh systems the analytical curves for the Fourier kernel components are obtained, and Fourier kernel themselves are built with binary rational number of samples of basis functions. The kernels are presented in matrix form and, as an example, recorded for a particular value of the discrete interval of N, equal to 8. The analysis spectral coefficients of the Fourier kernel

Angular power spectrum of galaxies in the 2MASS Redshift Survey

Science.gov (United States)

Ando, Shin'ichiro; Benoit-Lévy, Aurélien; Komatsu, Eiichiro

2018-02-01

We present the measurement and interpretation of the angular power spectrum of nearby galaxies in the 2MASS Redshift Survey catalogue with spectroscopic redshifts up to z ≈ 0.1. We detect the angular power spectrum up to a multipole of ℓ ≈ 1000. We find that the measured power spectrum is dominated by galaxies living inside nearby galaxy clusters and groups. We use the halo occupation distribution (HOD) formalism to model the power spectrum, obtaining a fit with reasonable parameters. These HOD parameters are in agreement with the 2MASS galaxy distribution we measure towards the known nearby galaxy clusters, confirming validity of our analysis.

[Application of wavelet transform and neural network in the near-infrared spectrum analysis of oil shale].

Science.gov (United States)

Li, Su-Yi; Ji, Yan-Ju; Liu, Wei-Yu; Wang, Zhi-Hong

2013-04-01

In the present study, an innovative method is proposed, employing both wavelet transform and neural network, to analyze the near-infrared spectrum data in oil shale survey. The method entails using db8 wavelet at 3 levels decomposition to process raw data, using the transformed data as the input matrix, and creating the model through neural network. To verify the validity of the method, this study analyzes 30 synthesized oil shale samples, in which 20 samples are randomly selected for network training, the other 10 for model prediction, and uses the full spectrum and the wavelet transformed spectrum to carry out 10 network models, respectively. Results show that the mean speed of the full spectrum neural network modeling is 570.33 seconds, and the predicted residual sum of squares (PRESS) and correlation coefficient of prediction are 0.006 012 and 0.843 75, respectively. In contrast, the mean speed of the wavelet network modeling method is 3.15 seconds, and the mean PRESS and correlation coefficient of prediction are 0.002 048 and 0.953 19, respectively. These results demonstrate that the wavelet neural network modeling method is significantly superior to the full spectrum neural network modeling method. This study not only provides a new method for more efficient and accurate detection of the oil content of oil shale, but also indicates the potential for applying wavelet transform and neutral network in broad near-infrared spectrum analysis.

Psychosocial interventions for internalised stigma in people with a schizophrenia-spectrum diagnosis: A systematic narrative synthesis and meta-analysis.

Science.gov (United States)

Wood, Lisa; Byrne, Rory; Varese, Filippo; Morrison, Anthony P

2016-10-01

It is acknowledged that people with a schizophrenia-spectrum diagnosis experience higher levels of stigma compared to any other mental health diagnosis. As a consequence, their experience of internalised stigma is likely to be the most detrimental and pervasive. Internalised stigma interventions have shown some benefits in those who experience serious mental illness including those with a schizophrenia-spectrum diagnosis. A systematic narrative review and meta-analysis were conducted examining the efficacy of internalised stigma interventions for people with a schizophrenia-spectrum diagnosis. Randomised Controlled Trials, controlled trials, and cohort studies were included and assessed against quality criteria. The search identified 12 studies; 7 randomised controlled trials, 3 cohort studies and 2 controlled trials. A variety of psychosocial interventions were utilised with the majority employing Cognitive Behaviour Therapy (CBT), psychoeducation and social skills training. The core outcomes used to examine the efficacy of the intervention were internalised stigma, self-esteem, empowerment, and functioning. The meta-analysis revealed an improvement in internalised stigma favouring the internalised stigma intervention but was not significant (5 RCTs, n=200). Self-efficacy and insight were significantly improved favouring the internalised stigma intervention. Internalised stigma interventions show promise in those with schizophrenia-spectrum diagnoses. Existing interventions have demonstrated small effects and employed small samples. Large scale RCTs are required to further develop the evidence base of more targeted interventions. Copyright © 2016 Elsevier B.V. All rights reserved.

Noise analysis of genome-scale protein synthesis using a discrete computational model of translation

Energy Technology Data Exchange (ETDEWEB)

Racle, Julien; Hatzimanikatis, Vassily, E-mail: vassily.hatzimanikatis@epfl.ch [Laboratory of Computational Systems Biotechnology, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland); Swiss Institute of Bioinformatics (SIB), CH-1015 Lausanne (Switzerland); Stefaniuk, Adam Jan [Laboratory of Computational Systems Biotechnology, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland)

2015-07-28

Noise in genetic networks has been the subject of extensive experimental and computational studies. However, very few of these studies have considered noise properties using mechanistic models that account for the discrete movement of ribosomes and RNA polymerases along their corresponding templates (messenger RNA (mRNA) and DNA). The large size of these systems, which scales with the number of genes, mRNA copies, codons per mRNA, and ribosomes, is responsible for some of the challenges. Additionally, one should be able to describe the dynamics of ribosome exchange between the free ribosome pool and those bound to mRNAs, as well as how mRNA species compete for ribosomes. We developed an efficient algorithm for stochastic simulations that addresses these issues and used it to study the contribution and trade-offs of noise to translation properties (rates, time delays, and rate-limiting steps). The algorithm scales linearly with the number of mRNA copies, which allowed us to study the importance of genome-scale competition between mRNAs for the same ribosomes. We determined that noise is minimized under conditions maximizing the specific synthesis rate. Moreover, sensitivity analysis of the stochastic system revealed the importance of the elongation rate in the resultant noise, whereas the translation initiation rate constant was more closely related to the average protein synthesis rate. We observed significant differences between our results and the noise properties of the most commonly used translation models. Overall, our studies demonstrate that the use of full mechanistic models is essential for the study of noise in translation and transcription.

Wind tunnel study of the power output spectrum in a micro wind farm

International Nuclear Information System (INIS)

Bossuyt, Juliaan; Meyers, Johan; Howland, Michael F.; Meneveau, Charles

2016-01-01

Instrumented small-scale porous disk models are used to study the spectrum of a surrogate for the power output in a micro wind farm with 100 models of wind turbines. The power spectra of individual porous disk models in the first row of the wind farm show the expected -5/3 power law at higher frequencies. Downstream models measure an increased variance due to wake effects. Conversely, the power spectrum of the sum of the power over the entire wind farm shows a peak at the turbine-to-turbine travel frequency between the model turbines, and a near -5/3 power law region at a much wider range of lower frequencies, confirming previous LES results. Comparison with the spectrum that would result when assuming that the signals are uncorrelated, highlights the strong effects of correlations and anti-correlations in the fluctuations at various frequencies. (paper)

Singular Spectrum Near a Singular Point of Friedrichs Model Operators of Absolute Type

International Nuclear Information System (INIS)

Iakovlev, Serguei I.

2006-01-01

In L 2 (R) we consider a family of self adjoint operators of the Friedrichs model: A m =|t| m +V. Here |t| m is the operator of multiplication by the corresponding function of the independent variable t element of R, and (perturbation) is a trace-class integral operator with a continuous Hermitian kernel ν(t,x) satisfying some smoothness condition. These absolute type operators have one singular point of order m>0. Conditions on the kernel ν(t,x) are found guaranteeing the absence of the point spectrum and the singular continuous one of such operators near the origin. These conditions are actually necessary and sufficient. They depend on the finiteness of the rank of a perturbation operator and on the order of singularity. The sharpness of these conditions is confirmed by counterexamples

First Observation of the Submillimeter Polarization Spectrum in a Translucent Molecular Cloud

Science.gov (United States)

Ashton, Peter C.; Ade, Peter A. R.; Angilè, Francesco E.; Benton, Steven J.; Devlin, Mark J.; Dober, Bradley; Fissel, Laura M.; Fukui, Yasuo; Galitzki, Nicholas; Gandilo, Natalie N.; Klein, Jeffrey; Korotkov, Andrei L.; Li, Zhi-Yun; Martin, Peter G.; Matthews, Tristan G.; Moncelsi, Lorenzo; Nakamura, Fumitaka; Netterfield, Calvin B.; Novak, Giles; Pascale, Enzo; Poidevin, Frédérick; Santos, Fabio P.; Savini, Giorgio; Scott, Douglas; Shariff, Jamil A.; Soler, Juan D.; Thomas, Nicholas E.; Tucker, Carole E.; Tucker, Gregory S.; Ward-Thompson, Derek

2018-04-01

Polarized emission from aligned dust is a crucial tool for studies of magnetism in the ISM, but a troublesome contaminant for studies of cosmic microwave background polarization. In each case, an understanding of the significance of the polarization signal requires well-calibrated physical models of dust grains. Despite decades of progress in theory and observation, polarized dust models remain largely underconstrained. During its 2012 flight, the balloon-borne telescope BLASTPol obtained simultaneous broadband polarimetric maps of a translucent molecular cloud at 250, 350, and 500 μm. Combining these data with polarimetry from the Planck 850 μm band, we have produced a submillimeter polarization spectrum, the first for a cloud of this type. We find the polarization degree to be largely constant across the four bands. This result introduces a new observable with the potential to place strong empirical constraints on ISM dust polarization models in a previously inaccessible density regime. Compared to models by Draine & Fraisse, our result disfavors two of their models for which all polarization arises due only to aligned silicate grains. By creating simple models for polarized emission in a translucent cloud, we verify that extinction within the cloud should have only a small effect on the polarization spectrum shape, compared to the diffuse ISM. Thus, we expect the measured polarization spectrum to be a valid check on diffuse ISM dust models. The general flatness of the observed polarization spectrum suggests a challenge to models where temperature and alignment degree are strongly correlated across major dust components.

Regulating the Emission Spectrum of CsPbBr3 from Green to Blue via Controlling the Temperature and Velocity of Microchannel Reactor

Directory of Open Access Journals (Sweden)

Yong Tang

2018-03-01

Full Text Available The ability to precisely obtain tunable spectrum of lead halide perovskite quantum dots (QDs is very important for applications, such as in lighting and display. Herein, we report a microchannel reactor method for synthesis of CsPbBr3 QDs with tunable spectrum. By adjusting the temperature and velocity of the microchannel reactor, the emission peaks of CsPbBr3 QDs ranging from 520 nm to 430 nm were obtained, which is wider than that of QDs obtained in a traditional flask without changing halide component. The mechanism of photoluminescence (PL spectral shift of CsPbBr3 QDs was investigated, the result shows that the supersaturation control enabled by the superior mass and heat transfer performance in the microchannel is the key to achieve the wide range of PL spectrum, with only a change in the setting of the temperature controller required. The wide spectrum of CsPbBr3 QDs can be applied to light-emitting diodes (LEDs, photoelectric sensors, lasers, etc.

A two-dimensional nodal model with turbulent effects for the synthesis of Si nano-particles by inductively coupled thermal plasmas

International Nuclear Information System (INIS)

Colombo, V; Ghedini, E; Gherardi, M; Sanibondi, P; Shigeta, M

2012-01-01

Nano-particle synthesis by means of inductively coupled plasma torches is a material process of large technological interest. Numerous parameters are involved in the optimization of this process; hence the development of numerical models for the prediction of thermal and magneto-fluid dynamics fields, precursor powder trajectories and thermal history, as well as nano-particle formation and growth, is necessary for the up-scaling of these devices from laboratory batch production to an industrial continuous process. In this work, a two-dimensional (2D) discrete-type model (nodal model) for the analysis of nano-powder nucleation and growth is presented, taking into account convection, diffusion and turbulent effects on particle formation. Discrete-type models feature high precision and reveal a great deal of information useful for clarifying the nano-particle formation process. Using Si as the precursor material, 2D simulations of a nano-particle synthesis RF plasma apparatus with a reaction chamber are carried out. Good agreement is found when comparing results obtained with this model with those coming from a well-established nucleation-coupled moment method. Moreover, the extended amount of obtainable information that characterizes the nodal model is underlined. (paper)

Toleration, Synthesis or Replacement?

DEFF Research Database (Denmark)

Holtermann, Jakob v. H.; Madsen, Mikael Rask

2016-01-01

, in order to answer is not yet another partisan suggestion, but rather an attempt at making intelligible both the oppositions and the possibilities of synthesis between normative and empirical approaches to law. Based on our assessment and rational reconstruction of current arguments and positions, we...... therefore outline a taxonomy consisting of the following three basic, ideal-types in terms of the epistemological understanding of the interface of law and empirical studies: toleration, synthesis and replacement. This tripartite model proves useful with a view to teasing out and better articulating...

ADAPTIVE FULL-SPECTRUM SOLOR ENERGY SYSTEMS

Energy Technology Data Exchange (ETDEWEB)

Byard D. Wood

2004-04-01

This RD&D project is a three year team effort to develop a hybrid solar lighting (HSL) system that transports solar light from a paraboloidal dish concentrator to a luminaire via a large core polymer fiber optic. The luminaire can be a device to distribute sunlight into a space for the production of algae or it can be a device that is a combination of solar lighting and electric lighting. A benchmark prototype system has been developed to evaluate the HSL system. Sunlight is collected using a one-meter paraboloidal concentrator dish with two-axis tracking. A secondary mirror consisting of eight planar-segmented mirrors directs the visible part of the spectrum to eight fibers (receiver) and subsequently to eight luminaires. This results in about 8,200 lumens incident at each fiber tip. Each fiber can illuminate about 16.7 m{sup 2} (180 ft{sup 2}) of office space. The IR spectrum is directed to a thermophotovoltaic (TPV) array to produce electricity. During this reporting period, the project team made advancements in the design of the second generation (Alpha) system. For the Alpha system, the eight individual 12 mm fibers have been replaced with a centralized bundle of 3 mm fibers. The TRNSYS Full-Spectrum Solar Energy System model has been updated and new components have been added. The TPV array and nonimaging device have been tested and progress has been made in the fiber transmission models. A test plan was developed for both the high-lumen tests and the study to determine the non-energy benefits of daylighting. The photobioreactor team also made major advancements in the testing of model scale and bench top lab-scale systems.

Two-directional synthesis as a tool for diversity-oriented synthesis: Synthesis of alkaloid scaffolds

Directory of Open Access Journals (Sweden)

Kieron M. G. O’Connell

2012-06-01

Full Text Available Two-directional synthesis represents an ideal strategy for the rapid elaboration of simple starting materials and their subsequent transformation into complex molecular architectures. As such, it is becoming recognised as an enabling technology for diversity-oriented synthesis. Herein, we provide a thorough account of our work combining two-directional synthesis with diversity-oriented synthesis, with particular reference to the synthesis of polycyclic alkaloid scaffolds.

Investigating the cross-cultural validity of DSM-5 autism spectrum disorder: evidence from Finnish and UK samples.

Science.gov (United States)

Mandy, William; Charman, Tony; Puura, Kaija; Skuse, David

2014-01-01

The recent Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition (DSM-5) reformulation of autism spectrum disorder has received empirical support from North American and UK samples. Autism spectrum disorder is an increasingly global diagnosis, and research is needed to discover how well it generalises beyond North America and the United Kingdom. We tested the applicability of the DSM-5 model to a sample of Finnish young people with autism spectrum disorder (n = 130) or the broader autism phenotype (n = 110). Confirmatory factor analysis tested the DSM-5 model in Finland and compared the fit of this model between Finnish and UK participants (autism spectrum disorder, n = 488; broader autism phenotype, n = 220). In both countries, autistic symptoms were measured using the Developmental, Diagnostic and Dimensional Interview. Replicating findings from English-speaking samples, the DSM-5 model fitted well in Finnish autism spectrum disorder participants, outperforming a Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition (DSM-IV) model. The DSM-5 model fitted equally well in Finnish and UK autism spectrum disorder samples. Among broader autism phenotype participants, this model fitted well in the United Kingdom but poorly in Finland, suggesting that cross-cultural variability may be greatest for milder autistic characteristics. We encourage researchers with data from other cultures to emulate our methodological approach, to map any cultural variability in the manifestation of autism spectrum disorder and the broader autism phenotype. This would be especially valuable given the ongoing revision of the International Classification of Diseases-11th Edition, the most global of the diagnostic manuals.

DOES THE CONSTRUCT OF INTERNET ADDICTION REFLECT A SINGLE ENTITY OR A SPECTRUM OF DISORDERS?

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Joël Billieux

2017-02-01

Full Text Available Objective: This article aimed to examine the issue of whether the construct of Internet addiction represents a single entity or a spectrum of disorders. Method: A literature review was performed and a conceptual synthesis was proposed. Results: Most research supports the notion that Internet addiction is a spectrum of Internet-related disorders, which pertain to addictive online behaviours, such as gaming and sexual activities. Although there are certain similarities between these behaviours, they are often associated with different socio-demographic and psychological variables (e.g., motivations and psychopathological symptoms, suggesting entities that are related, but still distinct. As constructs, addictive online activities are generally less heterogeneous than addictive use of the Internet, i.e., Internet addiction. Conclusions: The umbrella term “Internet addiction” is inadequate because it overlooks important differences between various addictive online activities. However, it may be unrealistic to expect a demise of the term before determining more clearly the acceptable level of internal heterogeneity of the psychopathological constructs.

Finite element design for the HPHT synthesis of diamond

Science.gov (United States)

Li, Rui; Ding, Mingming; Shi, Tongfei

2018-06-01

The finite element method is used to simulate the steady-state temperature field in diamond synthesis cell. The 2D and 3D models of the China-type cubic press with large deformation of the synthesis cell was established successfully, which has been verified by situ measurements of synthesis cell. The assembly design, component design and process design for the HPHT synthesis of diamond based on the finite element simulation were presented one by one. The temperature field in a high-pressure synthetic cavity for diamond production is optimized by adjusting the cavity assembly. A series of analysis about the influence of the pressure media parameters on the temperature field are examined through adjusting the model parameters. Furthermore, the formation mechanism of wasteland was studied in detail. It indicates that the wasteland is inevitably exists in the synthesis sample, the distribution of growth region of the diamond with hex-octahedral is move to the center of the synthesis sample from near the heater as the power increasing, and the growth conditions of high quality diamond is locating at the center of the synthesis sample. These works can offer suggestion and advice to the development and optimization of a diamond production process.

Two new prediction rules for spontaneous pregnancy leading to live birth among subfertile couples, based on the synthesis of three previous models.

NARCIS (Netherlands)

C.C. Hunault; J.D.F. Habbema (Dik); M.J.C. Eijkemans (René); J.A. Collins (John); J.L.H. Evers (Johannes); E.R. te Velde (Egbert)

2004-01-01

textabstractBACKGROUND: Several models have been published for the prediction of spontaneous pregnancy among subfertile patients. The aim of this study was to broaden the empirical basis for these predictions by making a synthesis of three previously published models. METHODS:

Mirror Neurons Modeled Through Spike-Timing-Dependent Plasticity are Affected by Channelopathies Associated with Autism Spectrum Disorder.

Science.gov (United States)

Antunes, Gabriela; Faria da Silva, Samuel F; Simoes de Souza, Fabio M

2018-06-01

Mirror neurons fire action potentials both when the agent performs a certain behavior and watches someone performing a similar action. Here, we present an original mirror neuron model based on the spike-timing-dependent plasticity (STDP) between two morpho-electrical models of neocortical pyramidal neurons. Both neurons fired spontaneously with basal firing rate that follows a Poisson distribution, and the STDP between them was modeled by the triplet algorithm. Our simulation results demonstrated that STDP is sufficient for the rise of mirror neuron function between the pairs of neocortical neurons. This is a proof of concept that pairs of neocortical neurons associating sensory inputs to motor outputs could operate like mirror neurons. In addition, we used the mirror neuron model to investigate whether channelopathies associated with autism spectrum disorder could impair the modeled mirror function. Our simulation results showed that impaired hyperpolarization-activated cationic currents (Ih) affected the mirror function between the pairs of neocortical neurons coupled by STDP.

A Synthesis Keynes-Monetarist and Real Business Cycle Model to Inflation and Unemployment in Indonesia 2000.1-2014.4

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Aris Soelistyo

2017-06-01

Full Text Available This research is addressed for the construction of Synthesis between Keynesian, Monetarist and Real Business Cycle Model to the inflation and unemployment Data is used quarterly data 2000.1 - 2014.4, The result of this research with the Keynesian model is the aggregate demand gap has no significance effect to inflation rate and the unemployment rate. But when model of variable input mount the unemployment, exchange rate, wage and the aggregate demand gap of hence yielding elastic inflation elasticity finding of positive of equal to 2,48 to the unemployment rate, and the inflation elasticity to foreign exchange is inelastic positive significance of equal to 0,88. As for the influence of wages to inflation is significantly negative elastic of equal to – 1,89. Besides, in model is also shown by condition of significance of influence of variable of aggregate demand gap to inflation of equal to 0.31. Meanwhile, Inflation in perspective monetarist viewed as by a monetary phenomenon, where the inflation influenced by money supply of equal to 1.858. Besides, Monetarist also express of relation significance of between GDP summed ugly is money supply is inelastic positive significance of equal to 0.1247. The RBC Model shows that the investment elasticity to output is significance inelastic positive equal to 0.405467, that way also with the influence of the population to GDP is significance negative equal to - 1.259925 . The other side, is founded by of Unemployment elasticity to wage rate is significance positive of equal to 0.413. Meanwhile, with the model of synthesis Keynes-Monetarist and RBC lay open that output (GDP is influenced by the positive significance of equal to 0.206026 . The synthesis model is also expressed by that governmental fiscal governmental expenditure as a means of shows influence which significant to unemployment equal to 0.149. While component amount of money supply, affecting negativity significance to unemployment of equal to

High-Frequency Axial Fatigue Test Procedures for Spectrum Loading

Science.gov (United States)