Single channel blind source separation based on ICA feature extraction

Institute of Scientific and Technical Information of China (English)

无

2007-01-01

A new technique is proposed to solve the blind source separation (BSS) given only a single channel observation. The basis functions and the density of the coefficients of source signals learned by ICA are used as the prior knowledge. Based on the learned prior information the learning rules of single channel BSS are presented by maximizing the joint log likelihood of the mixed sources to obtain source signals from single observation,in which the posterior density of the given measurements is maximized. The experimental results exhibit a successful separation performance for mixtures of speech and music signals.

Underdetermined Blind Audio Source Separation Using Modal Decomposition

Directory of Open Access Journals (Sweden)

Abdeldjalil Aïssa-El-Bey

2007-03-01

Full Text Available This paper introduces new algorithms for the blind separation of audio sources using modal decomposition. Indeed, audio signals and, in particular, musical signals can be well approximated by a sum of damped sinusoidal (modal components. Based on this representation, we propose a two-step approach consisting of a signal analysis (extraction of the modal components followed by a signal synthesis (grouping of the components belonging to the same source using vector clustering. For the signal analysis, two existing algorithms are considered and compared: namely the EMD (empirical mode decomposition algorithm and a parametric estimation algorithm using ESPRIT technique. A major advantage of the proposed method resides in its validity for both instantaneous and convolutive mixtures and its ability to separate more sources than sensors. Simulation results are given to compare and assess the performance of the proposed algorithms.

Underdetermined Blind Audio Source Separation Using Modal Decomposition

Directory of Open Access Journals (Sweden)

Aïssa-El-Bey Abdeldjalil

2007-01-01

Full Text Available This paper introduces new algorithms for the blind separation of audio sources using modal decomposition. Indeed, audio signals and, in particular, musical signals can be well approximated by a sum of damped sinusoidal (modal components. Based on this representation, we propose a two-step approach consisting of a signal analysis (extraction of the modal components followed by a signal synthesis (grouping of the components belonging to the same source using vector clustering. For the signal analysis, two existing algorithms are considered and compared: namely the EMD (empirical mode decomposition algorithm and a parametric estimation algorithm using ESPRIT technique. A major advantage of the proposed method resides in its validity for both instantaneous and convolutive mixtures and its ability to separate more sources than sensors. Simulation results are given to compare and assess the performance of the proposed algorithms.

Extended nonnegative tensor factorisation models for musical sound source separation.

Science.gov (United States)

FitzGerald, Derry; Cranitch, Matt; Coyle, Eugene

2008-01-01

Recently, shift-invariant tensor factorisation algorithms have been proposed for the purposes of sound source separation of pitched musical instruments. However, in practice, existing algorithms require the use of log-frequency spectrograms to allow shift invariance in frequency which causes problems when attempting to resynthesise the separated sources. Further, it is difficult to impose harmonicity constraints on the recovered basis functions. This paper proposes a new additive synthesis-based approach which allows the use of linear-frequency spectrograms as well as imposing strict harmonic constraints, resulting in an improved model. Further, these additional constraints allow the addition of a source filter model to the factorisation framework, and an extended model which is capable of separating mixtures of pitched and percussive instruments simultaneously.

Extended Nonnegative Tensor Factorisation Models for Musical Sound Source Separation

Directory of Open Access Journals (Sweden)

Derry FitzGerald

2008-01-01

Full Text Available Recently, shift-invariant tensor factorisation algorithms have been proposed for the purposes of sound source separation of pitched musical instruments. However, in practice, existing algorithms require the use of log-frequency spectrograms to allow shift invariance in frequency which causes problems when attempting to resynthesise the separated sources. Further, it is difficult to impose harmonicity constraints on the recovered basis functions. This paper proposes a new additive synthesis-based approach which allows the use of linear-frequency spectrograms as well as imposing strict harmonic constraints, resulting in an improved model. Further, these additional constraints allow the addition of a source filter model to the factorisation framework, and an extended model which is capable of separating mixtures of pitched and percussive instruments simultaneously.

Separation of non-stationary multi-source sound field based on the interpolated time-domain equivalent source method

Science.gov (United States)

Bi, Chuan-Xing; Geng, Lin; Zhang, Xiao-Zheng

2016-05-01

In the sound field with multiple non-stationary sources, the measured pressure is the sum of the pressures generated by all sources, and thus cannot be used directly for studying the vibration and sound radiation characteristics of every source alone. This paper proposes a separation model based on the interpolated time-domain equivalent source method (ITDESM) to separate the pressure field belonging to every source from the non-stationary multi-source sound field. In the proposed method, ITDESM is first extended to establish the relationship between the mixed time-dependent pressure and all the equivalent sources distributed on every source with known location and geometry information, and all the equivalent source strengths at each time step are solved by an iterative solving process; then, the corresponding equivalent source strengths of one interested source are used to calculate the pressure field generated by that source alone. Numerical simulation of two baffled circular pistons demonstrates that the proposed method can be effective in separating the non-stationary pressure generated by every source alone in both time and space domains. An experiment with two speakers in a semi-anechoic chamber further evidences the effectiveness of the proposed method.

Comparison of methods for separating vibration sources in rotating machinery

Science.gov (United States)

Klein, Renata

2017-12-01

Vibro-acoustic signatures are widely used for diagnostics of rotating machinery. Vibration based automatic diagnostics systems need to achieve a good separation between signals generated by different sources. The separation task may be challenging, since the effects of the different vibration sources often overlap. In particular, there is a need to separate between signals related to the natural frequencies of the structure and signals resulting from the rotating components (signal whitening), as well as a need to separate between signals generated by asynchronous components like bearings and signals generated by cyclo-stationary components like gears. Several methods were proposed to achieve the above separation tasks. The present study compares between some of these methods. The paper also presents a new method for whitening, Adaptive Clutter Separation, as well as a new efficient algorithm for dephase, which separates between asynchronous and cyclo-stationary signals. For whitening the study compares between liftering of the high quefrencies and adaptive clutter separation. For separating between the asynchronous and the cyclo-stationary signals the study compares between liftering in the quefrency domain and dephase. The methods are compared using both simulated signals and real data.

Carbon footprint of urban source separation for nutrient recovery.

Science.gov (United States)

Kjerstadius, H; Bernstad Saraiva, A; Spångberg, J; Davidsson, Å

2017-07-15

Source separation systems for the management of domestic wastewater and food waste has been suggested as more sustainable sanitation systems for urban areas. The present study used an attributional life cycle assessment to investigate the carbon footprint and potential for nutrient recovery of two sanitation systems for a hypothetical urban area in Southern Sweden. The systems represented a typical Swedish conventional system and a possible source separation system with increased nutrient recovery. The assessment included the management chain from household collection, transport, treatment and final return of nutrients to agriculture or disposal of the residuals. The results for carbon footprint and nutrient recovery (phosphorus and nitrogen) concluded that the source separation system could increase nutrient recovery (0.30-0.38 kg P capita -1 year -1 and 3.10-3.28 kg N capita -1 year -1 ), while decreasing the carbon footprint (-24 to -58 kg CO 2 -eq. capita -1 year -1 ), compared to the conventional system. The nutrient recovery was increased by the use of struvite precipitation and ammonium stripping at the wastewater treatment plant. The carbon footprint decreased, mainly due to the increased biogas production, increased replacement of mineral fertilizer in agriculture and less emissions of nitrous oxide from wastewater treatment. In conclusion, the study showed that source separation systems could potentially be used to increase nutrient recovery from urban areas, while decreasing the climate impact. Copyright © 2017 Elsevier Ltd. All rights reserved.

Blind Separation of Nonstationary Sources Based on Spatial Time-Frequency Distributions

Directory of Open Access Journals (Sweden)

Zhang Yimin

2006-01-01

Full Text Available Blind source separation (BSS based on spatial time-frequency distributions (STFDs provides improved performance over blind source separation methods based on second-order statistics, when dealing with signals that are localized in the time-frequency (t-f domain. In this paper, we propose the use of STFD matrices for both whitening and recovery of the mixing matrix, which are two stages commonly required in many BSS methods, to provide robust BSS performance to noise. In addition, a simple method is proposed to select the auto- and cross-term regions of time-frequency distribution (TFD. To further improve the BSS performance, t-f grouping techniques are introduced to reduce the number of signals under consideration, and to allow the receiver array to separate more sources than the number of array sensors, provided that the sources have disjoint t-f signatures. With the use of one or more techniques proposed in this paper, improved performance of blind separation of nonstationary signals can be achieved.

Bayesian mixture models for source separation in MEG

International Nuclear Information System (INIS)

Calvetti, Daniela; Homa, Laura; Somersalo, Erkki

2011-01-01

This paper discusses the problem of imaging electromagnetic brain activity from measurements of the induced magnetic field outside the head. This imaging modality, magnetoencephalography (MEG), is known to be severely ill posed, and in order to obtain useful estimates for the activity map, complementary information needs to be used to regularize the problem. In this paper, a particular emphasis is on finding non-superficial focal sources that induce a magnetic field that may be confused with noise due to external sources and with distributed brain noise. The data are assumed to come from a mixture of a focal source and a spatially distributed possibly virtual source; hence, to differentiate between those two components, the problem is solved within a Bayesian framework, with a mixture model prior encoding the information that different sources may be concurrently active. The mixture model prior combines one density that favors strongly focal sources and another that favors spatially distributed sources, interpreted as clutter in the source estimation. Furthermore, to address the challenge of localizing deep focal sources, a novel depth sounding algorithm is suggested, and it is shown with simulated data that the method is able to distinguish between a signal arising from a deep focal source and a clutter signal. (paper)

Source separation on hyperspectral cube applied to dermatology

Science.gov (United States)

Mitra, J.; Jolivot, R.; Vabres, P.; Marzani, F. S.

2010-03-01

This paper proposes a method of quantification of the components underlying the human skin that are supposed to be responsible for the effective reflectance spectrum of the skin over the visible wavelength. The method is based on independent component analysis assuming that the epidermal melanin and the dermal haemoglobin absorbance spectra are independent of each other. The method extracts the source spectra that correspond to the ideal absorbance spectra of melanin and haemoglobin. The noisy melanin spectrum is fixed using a polynomial fit and the quantifications associated with it are reestimated. The results produce feasible quantifications of each source component in the examined skin patch.

The Effects of Environmental Management Systems on Source Separation in the Work and Home Settings

Directory of Open Access Journals (Sweden)

Chris von Borgstede

2012-06-01

Full Text Available Measures that challenge the generation of waste are needed to address the global problem of the increasing volumes of waste that are generated in both private homes and workplaces. Source separation at the workplace is commonly implemented by environmental management systems (EMS. In the present study, the relationship between source separation at work and at home was investigated. A questionnaire that maps psychological and behavioural predictors of source separation was distributed to employees at different workplaces. The results show that respondents with awareness of EMS report higher levels of source separation at work, stronger environmental concern, personal and social norms, and perceive source separation to be less difficult. Furthermore, the results support the notion that after the adoption of EMS at the workplace, source separation at work spills over into source separation in the household. The potential implications for environmental management systems are discussed.

Municipal solid waste source-separated collection in China: A comparative analysis

International Nuclear Information System (INIS)

Tai Jun; Zhang Weiqian; Che Yue; Feng Di

2011-01-01

A pilot program focusing on municipal solid waste (MSW) source-separated collection was launched in eight major cities throughout China in 2000. Detailed investigations were carried out and a comprehensive system was constructed to evaluate the effects of the eight-year implementation in those cities. This paper provides an overview of different methods of collection, transportation, and treatment of MSW in the eight cities; as well as making a comparative analysis of MSW source-separated collection in China. Information about the quantity and composition of MSW shows that the characteristics of MSW are similar, which are low calorific value, high moisture content and high proportion of organisms. Differences which exist among the eight cities in municipal solid waste management (MSWM) are presented in this paper. Only Beijing and Shanghai demonstrated a relatively effective result in the implementation of MSW source-separated collection. While the six remaining cities result in poor performance. Considering the current status of MSWM, source-separated collection should be a key priority. Thus, a wider range of cities should participate in this program instead of merely the eight pilot cities. It is evident that an integrated MSWM system is urgently needed. Kitchen waste and recyclables are encouraged to be separated at the source. Stakeholders involved play an important role in MSWM, thus their responsibilities should be clearly identified. Improvement in legislation, coordination mechanisms and public education are problematic issues that need to be addressed.

Low Complexity Bayesian Single Channel Source Separation

DEFF Research Database (Denmark)

Beierholm, Thomas; Pedersen, Brian Dam; Winther, Ole

2004-01-01

can be estimated quite precisely using ML-II, but the estimation is quite sensitive to the accuracy of the priors as opposed to the source separation quality for known mixing coefficients, which is quite insensitive to the accuracy of the priors. Finally, we discuss how to improve our approach while...

Empirical Study on Factors Influencing Residents' Behavior of Separating Household Wastes at Source

Institute of Scientific and Technical Information of China (English)

Qu Ying; Zhu Qinghua; Murray Haight

2007-01-01

Source separation is the basic premise for making effective use of household wastes. In eight cities of China, however, several pilot projects of source separation finally failed because of the poor participation rate of residents. In order to solve this problem, identifying those factors that influence residents' behavior of source separation becomes crucial. By means of questionnaire survey, we conducted descriptive analysis and exploratory factor analysis. The results show that trouble-feeling, moral notion, environment protection, public education, environment value and knowledge deficiency are the main factors that play an important role for residents in deciding to separate their household wastes. Also, according to the contribution percentage of the six main factors to the total behavior of source separation, their influencing power is analyzed, which will provide suggestions on household waste management for policy makers and decision makers in China.

Overcomplete Blind Source Separation by Combining ICA and Binary Time-Frequency Masking

DEFF Research Database (Denmark)

Pedersen, Michael Syskind; Wang, DeLiang; Larsen, Jan

2005-01-01

a novel method for over-complete blind source separation. Two powerful source separation techniques have been combined, independent component analysis and binary time-frequency masking. Hereby, it is possible to iteratively extract each speech signal from the mixture. By using merely two microphones we...

A Separation Algorithm for Sources with Temporal Structure Only Using Second-order Statistics

Directory of Open Access Journals (Sweden)

J.G. Wang

2013-09-01

Full Text Available Unlike conventional blind source separation (BSS deals with independent identically distributed (i.i.d. sources, this paper addresses the separation from mixtures of sources with temporal structure, such as linear autocorrelations. Many sequential extraction algorithms have been reported, resulting in inevitable cumulated errors introduced by the deflation scheme. We propose a robust separation algorithm to recover original sources simultaneously, through a joint diagonalizer of several average delayed covariance matrices at positions of the optimal time delay and its integers. The proposed algorithm is computationally simple and efficient, since it is based on the second-order statistics only. Extensive simulation results confirm the validity and high performance of the algorithm. Compared with related extraction algorithms, its separation signal-to-noise rate for a desired source can reach 20dB higher, and it seems rather insensitive to the estimation error of the time delay.

Joint Matrices Decompositions and Blind Source Separation

Czech Academy of Sciences Publication Activity Database

Chabriel, G.; Kleinsteuber, M.; Moreau, E.; Shen, H.; Tichavský, Petr; Yeredor, A.

2014-01-01

Roč. 31, č. 3 (2014), s. 34-43 ISSN 1053-5888 R&D Projects: GA ČR GA102/09/1278 Institutional support: RVO:67985556 Keywords : joint matrices decomposition * tensor decomposition * blind source separation Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 5.852, year: 2014 http://library.utia.cas.cz/separaty/2014/SI/tichavsky-0427607.pdf

Blind source separation advances in theory, algorithms and applications

CERN Document Server

Wang, Wenwu

2014-01-01

Blind Source Separation intends to report the new results of the efforts on the study of Blind Source Separation (BSS). The book collects novel research ideas and some training in BSS, independent component analysis (ICA), artificial intelligence and signal processing applications. Furthermore, the research results previously scattered in many journals and conferences worldwide are methodically edited and presented in a unified form. The book is likely to be of interest to university researchers, R&D engineers and graduate students in computer science and electronics who wish to learn the core principles, methods, algorithms, and applications of BSS. Dr. Ganesh R. Naik works at University of Technology, Sydney, Australia; Dr. Wenwu Wang works at University of Surrey, UK.

Fate of pharmaceuticals in full-scale source separated sanitation system

NARCIS (Netherlands)

Butkovskyi, A.; Hernandez Leal, L.; Rijnaarts, H.H.M.; Zeeman, G.

2015-01-01

Removal of 14 pharmaceuticals and 3 of their transformation products was studied in a full-scale source separated sanitation system with separate collection and treatment of black water and grey water. Black water is treated in an up-flow anaerobic sludge blanket (UASB) reactor followed by

Blind source separation problem in GPS time series

Science.gov (United States)

Gualandi, A.; Serpelloni, E.; Belardinelli, M. E.

2016-04-01

A critical point in the analysis of ground displacement time series, as those recorded by space geodetic techniques, is the development of data-driven methods that allow the different sources of deformation to be discerned and characterized in the space and time domains. Multivariate statistic includes several approaches that can be considered as a part of data-driven methods. A widely used technique is the principal component analysis (PCA), which allows us to reduce the dimensionality of the data space while maintaining most of the variance of the dataset explained. However, PCA does not perform well in finding the solution to the so-called blind source separation (BSS) problem, i.e., in recovering and separating the original sources that generate the observed data. This is mainly due to the fact that PCA minimizes the misfit calculated using an L2 norm (χ 2), looking for a new Euclidean space where the projected data are uncorrelated. The independent component analysis (ICA) is a popular technique adopted to approach the BSS problem. However, the independence condition is not easy to impose, and it is often necessary to introduce some approximations. To work around this problem, we test the use of a modified variational Bayesian ICA (vbICA) method to recover the multiple sources of ground deformation even in the presence of missing data. The vbICA method models the probability density function (pdf) of each source signal using a mix of Gaussian distributions, allowing for more flexibility in the description of the pdf of the sources with respect to standard ICA, and giving a more reliable estimate of them. Here we present its application to synthetic global positioning system (GPS) position time series, generated by simulating deformation near an active fault, including inter-seismic, co-seismic, and post-seismic signals, plus seasonal signals and noise, and an additional time-dependent volcanic source. We evaluate the ability of the PCA and ICA decomposition

Audio Source Separation in Reverberant Environments Using β-Divergence-Based Nonnegative Factorization

DEFF Research Database (Denmark)

Fakhry, Mahmoud; Svaizer, Piergiorgio; Omologo, Maurizio

2017-01-01

-maximization algorithm and used to separate the signals by means of multichannel Wiener filtering. We propose to estimate these parameters by applying nonnegative factorization based on prior information on source variances. In the nonnegative factorization, spectral basis matrices can be defined as the prior...... information. The matrices can be either extracted or indirectly made available through a redundant library that is trained in advance. In a separate step, applying nonnegative tensor factorization, two algorithms are proposed in order to either extract or detect the basis matrices that best represent......In Gaussian model-based multichannel audio source separation, the likelihood of observed mixtures of source signals is parametrized by source spectral variances and by associated spatial covariance matrices. These parameters are estimated by maximizing the likelihood through an expectation...

Energy conversion of source separated packaging; Energiutvinning ur kaellsorterade foerpackningsfraktioner

Energy Technology Data Exchange (ETDEWEB)

Blidholm, O; Wiklund, S E [AaF-Energikonsult (Sweden); Bauer, A C [Energikonsult A. Bauer (Sweden)

1997-02-01

The basic idea of this project is to study the possibilities to use source separated combustible material for energy conversion in conventional solid fuel boilers (i.e. not municipal waste incineration plants). The project has been carried out in three phases. During phase 1 and 2 a number of fuel analyses of different fractions were carried out. During phase 3 two combustion tests were carried out; (1) a boiler with grate equipped with cyclone, electrostatic precipitator and flue gas condenser, and (2) a bubbling fluidized bed boiler with electrostatic precipitator and flue gas condenser. During the tests source separated paper and plastic packagings were co-fired with biomass fuels. The mixing rate of packagings was approximately 15%. This study reports the results of phase 3 and the conclusions of the whole project. The technical terms of using packaging as fuel are good. The technique is available for shredding both paper and plastic packaging. The material can be co-fired with biomass. The economical terms of using source separated packaging for energy conversion can be very advantageous, but can also form obstacles. The result is to a high degree guided by such facts as how the fuel is collected, transported, reduced in size and handled at the combustion plant. The results of the combustion tests show that the environmental terms of using source separated packaging for energy conversion are good. The emissions of heavy metals into the atmosphere are very low. The emissions are well below the emission standards for waste incineration plants. 35 figs, 13 tabs, 8 appendices

An incentive-based source separation model for sustainable municipal solid waste management in China.

Science.gov (United States)

Xu, Wanying; Zhou, Chuanbin; Lan, Yajun; Jin, Jiasheng; Cao, Aixin

2015-05-01

Municipal solid waste (MSW) management (MSWM) is most important and challenging in large urban communities. Sound community-based waste management systems normally include waste reduction and material recycling elements, often entailing the separation of recyclable materials by the residents. To increase the efficiency of source separation and recycling, an incentive-based source separation model was designed and this model was tested in 76 households in Guiyang, a city of almost three million people in southwest China. This model embraced the concepts of rewarding households for sorting organic waste, government funds for waste reduction, and introducing small recycling enterprises for promoting source separation. Results show that after one year of operation, the waste reduction rate was 87.3%, and the comprehensive net benefit under the incentive-based source separation model increased by 18.3 CNY tonne(-1) (2.4 Euros tonne(-1)), compared to that under the normal model. The stakeholder analysis (SA) shows that the centralized MSW disposal enterprises had minimum interest and may oppose the start-up of a new recycling system, while small recycling enterprises had a primary interest in promoting the incentive-based source separation model, but they had the least ability to make any change to the current recycling system. The strategies for promoting this incentive-based source separation model are also discussed in this study. © The Author(s) 2015.

Ion source development for the on-line isotope separator at GSI

International Nuclear Information System (INIS)

Kirchner, R.; Burkard, K.; Hueller, W.; Klepper, O.

1991-08-01

The progress in the understanding of ion sources for isotope separation on-line and the feasibility of bunched beams of relatively refractory elements is reported. The ultra-high temperature FEBIAD-H ion source, facilitating the mounting of catchers and window compared to the earlier F-version, enables bunched beams of the elements with adsorption enthalpies up to almost 6 eV, e.g. of Be, Al, Ca, Cr, Fe, Co, Ni, Sr, Pd, Ba, Yb, and Au. This way also chemical selectivity for these elements may be achieved, at least to some extent, for isotopes with halflives > or approx.1 minute, including especially the difficult separation of alkaline-earth isotopes from isobaric alkalines. These studies reveal, however, also a principal difficulty in the on-line separation of refractory elements, namely their tendency, increasing with ΔH a , to re-diffuse after release from the catcher into the bulk of the hot source enclosure. (orig.)

Constrained Null Space Component Analysis for Semiblind Source Separation Problem.

Science.gov (United States)

Hwang, Wen-Liang; Lu, Keng-Shih; Ho, Jinn

2018-02-01

The blind source separation (BSS) problem extracts unknown sources from observations of their unknown mixtures. A current trend in BSS is the semiblind approach, which incorporates prior information on sources or how the sources are mixed. The constrained independent component analysis (ICA) approach has been studied to impose constraints on the famous ICA framework. We introduced an alternative approach based on the null space component (NCA) framework and referred to the approach as the c-NCA approach. We also presented the c-NCA algorithm that uses signal-dependent semidefinite operators, which is a bilinear mapping, as signatures for operator design in the c-NCA approach. Theoretically, we showed that the source estimation of the c-NCA algorithm converges with a convergence rate dependent on the decay of the sequence, obtained by applying the estimated operators on corresponding sources. The c-NCA can be formulated as a deterministic constrained optimization method, and thus, it can take advantage of solvers developed in optimization society for solving the BSS problem. As examples, we demonstrated electroencephalogram interference rejection problems can be solved by the c-NCA with proximal splitting algorithms by incorporating a sparsity-enforcing separation model and considering the case when reference signals are available.

Gearbox Fault Diagnosis in a Wind Turbine Using Single Sensor Based Blind Source Separation

Directory of Open Access Journals (Sweden)

Yuning Qian

2016-01-01

Full Text Available This paper presents a single sensor based blind source separation approach, namely, the wavelet-assisted stationary subspace analysis (WSSA, for gearbox fault diagnosis in a wind turbine. Continuous wavelet transform (CWT is used as a preprocessing tool to decompose a single sensor measurement data into a set of wavelet coefficients to meet the multidimensional requirement of the stationary subspace analysis (SSA. The SSA is a blind source separation technique that can separate the multidimensional signals into stationary and nonstationary source components without the need for independency and prior information of the source signals. After that, the separated nonstationary source component with the maximum kurtosis value is analyzed by the enveloping spectral analysis to identify potential fault-related characteristic frequencies. Case studies performed on a wind turbine gearbox test system verify the effectiveness of the WSSA approach and indicate that it outperforms independent component analysis (ICA and empirical mode decomposition (EMD, as well as the spectral-kurtosis-based enveloping, for wind turbine gearbox fault diagnosis.

Using spatiotemporal source separation to identify prominent features in multichannel data without sinusoidal filters.

Science.gov (United States)

Cohen, Michael X

2017-09-27

The number of simultaneously recorded electrodes in neuroscience is steadily increasing, providing new opportunities for understanding brain function, but also new challenges for appropriately dealing with the increase in dimensionality. Multivariate source separation analysis methods have been particularly effective at improving signal-to-noise ratio while reducing the dimensionality of the data and are widely used for cleaning, classifying and source-localizing multichannel neural time series data. Most source separation methods produce a spatial component (that is, a weighted combination of channels to produce one time series); here, this is extended to apply source separation to a time series, with the idea of obtaining a weighted combination of successive time points, such that the weights are optimized to satisfy some criteria. This is achieved via a two-stage source separation procedure, in which an optimal spatial filter is first constructed and then its optimal temporal basis function is computed. This second stage is achieved with a time-delay-embedding matrix, in which additional rows of a matrix are created from time-delayed versions of existing rows. The optimal spatial and temporal weights can be obtained by solving a generalized eigendecomposition of covariance matrices. The method is demonstrated in simulated data and in an empirical electroencephalogram study on theta-band activity during response conflict. Spatiotemporal source separation has several advantages, including defining empirical filters without the need to apply sinusoidal narrowband filters. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Separation of radiation from two sources from their known radiated sum field

DEFF Research Database (Denmark)

Laitinen, Tommi; Pivnenko, Sergey

2011-01-01

This paper presents a technique for complete and exact separation of the radiated fields of two sources (at the same frequency) from the knowledge of their radiated sum field. The two sources can be arbitrary but it must be possible to enclose the sources inside their own non-intersecting minimum...

Surface-ionization ion source designed for in-beam operation with the BEMS-2 isotope separator

International Nuclear Information System (INIS)

Bogdanov, D.D.; Voboril, J.; Demyanov, A.V.; Karnaukhov, V.A.; Petrov, L.A.

1976-01-01

A surface-ionization ion source designed to operate in combination with the BEMS-2 isotope separator in a heavy ion beam is described. The ion source is adjusted for the separation of rare-earth elements. The separation efficiency for 150 Dy is determined to be equal to about 20% at the ionizer temperature of 2600 deg K. The hold-up times for praseodymium, promethium and dysprosium in the ion source range from 5 to 10 sec at the ionizer temperature of 2500-2700 deg K

On the sources of technological change: What do the models assume?

International Nuclear Information System (INIS)

Clarke, Leon; Weyant, John; Edmonds, Jae

2008-01-01

It is widely acknowledged that technological change can substantially reduce the costs of stabilizing atmospheric concentrations of greenhouse gases. This paper discusses the sources of technological change and the representations of these sources in formal models of energy and the environment. The paper distinguishes between three major sources of technological change-R and D, learning-by-doing and spillovers-and introduces a conceptual framework for linking modeling approaches to assumptions about these real-world sources. A selective review of modeling approaches, including those employing exogenous technological change, suggests that most formal models have meaningful real-world interpretations that focus on a subset of possible sources of technological change while downplaying the roles of others

Technologies for the treatment of source-separated urine in the ...

African Journals Online (AJOL)

Technologies for the treatment of source-separated urine in the eThekwini ... This practice can lead to environmental pollution, since urine contains high amounts of ... produces only distilled water and a small amount of sludge as by-products.

Rhythmic entrainment source separation: Optimizing analyses of neural responses to rhythmic sensory stimulation

OpenAIRE

Cohen, M.S.; Gulbinaite, R.

2017-01-01

Steady-state evoked potentials (SSEPs) are rhythmic brain responses to rhythmic sensory stimulation, and are often used to study perceptual and attentional processes. We present a data analysis method for maximizing the signal-to-noise ratio of the narrow-band steady-state response in the frequency and time-frequency domains. The method, termed rhythmic entrainment source separation (RESS), is based on denoising source separation approaches that take advantage of the simultaneous but differen...

Life cycle assessment of a household solid waste source separation programme: a Swedish case study.

Science.gov (United States)

Bernstad, Anna; la Cour Jansen, Jes; Aspegren, Henrik

2011-10-01

The environmental impact of an extended property close source-separation system for solid household waste (i.e., a systems for collection of recyclables from domestic properties) is investigated in a residential area in southern Sweden. Since 2001, households have been able to source-separate waste into six fractions of dry recyclables and food waste sorting. The current system was evaluated using the EASEWASTE life cycle assessment tool. Current status is compared with an ideal scenario in which households display perfect source-separation behaviour and a scenario without any material recycling. Results show that current recycling provides substantial environmental benefits compared to a non-recycling alternative. The environmental benefit varies greatly between recyclable fractions, and the recyclables currently most frequently source-separated by households are often not the most beneficial from an environmental perspective. With optimal source-separation of all recyclables, the current net contribution to global warming could be changed to a net-avoidance while current avoidance of nutrient enrichment, acidification and photochemical ozone formation could be doubled. Sensitivity analyses show that the type of energy substituted by incineration of non-recycled waste, as well as energy used in recycling processes and in the production of materials substituted by waste recycling, is of high relevance for the attained results.

Evaluating source separation of plastic waste using conjoint analysis.

Science.gov (United States)

Nakatani, Jun; Aramaki, Toshiya; Hanaki, Keisuke

2008-11-01

Using conjoint analysis, we estimated the willingness to pay (WTP) of households for source separation of plastic waste and the improvement of related environmental impacts, the residents' loss of life expectancy (LLE), the landfill capacity, and the CO2 emissions. Unreliable respondents were identified and removed from the sample based on their answers to follow-up questions. It was found that the utility associated with reducing LLE and with the landfill capacity were both well expressed by logarithmic functions, but that residents were indifferent to the level of CO2 emissions even though they approved of CO2 reduction. In addition, residents derived utility from the act of separating plastic waste, irrespective of its environmental impacts; that is, they were willing to practice the separation of plastic waste at home in anticipation of its "invisible effects", such as the improvement of citizens' attitudes toward solid waste issues.

Cultured Cortical Neurons Can Perform Blind Source Separation According to the Free-Energy Principle

Science.gov (United States)

Isomura, Takuya; Kotani, Kiyoshi; Jimbo, Yasuhiko

2015-01-01

Blind source separation is the computation underlying the cocktail party effect––a partygoer can distinguish a particular talker’s voice from the ambient noise. Early studies indicated that the brain might use blind source separation as a signal processing strategy for sensory perception and numerous mathematical models have been proposed; however, it remains unclear how the neural networks extract particular sources from a complex mixture of inputs. We discovered that neurons in cultures of dissociated rat cortical cells could learn to represent particular sources while filtering out other signals. Specifically, the distinct classes of neurons in the culture learned to respond to the distinct sources after repeating training stimulation. Moreover, the neural network structures changed to reduce free energy, as predicted by the free-energy principle, a candidate unified theory of learning and memory, and by Jaynes’ principle of maximum entropy. This implicit learning can only be explained by some form of Hebbian plasticity. These results are the first in vitro (as opposed to in silico) demonstration of neural networks performing blind source separation, and the first formal demonstration of neuronal self-organization under the free energy principle. PMID:26690814

Cultured Cortical Neurons Can Perform Blind Source Separation According to the Free-Energy Principle.

Directory of Open Access Journals (Sweden)

Takuya Isomura

2015-12-01

Full Text Available Blind source separation is the computation underlying the cocktail party effect--a partygoer can distinguish a particular talker's voice from the ambient noise. Early studies indicated that the brain might use blind source separation as a signal processing strategy for sensory perception and numerous mathematical models have been proposed; however, it remains unclear how the neural networks extract particular sources from a complex mixture of inputs. We discovered that neurons in cultures of dissociated rat cortical cells could learn to represent particular sources while filtering out other signals. Specifically, the distinct classes of neurons in the culture learned to respond to the distinct sources after repeating training stimulation. Moreover, the neural network structures changed to reduce free energy, as predicted by the free-energy principle, a candidate unified theory of learning and memory, and by Jaynes' principle of maximum entropy. This implicit learning can only be explained by some form of Hebbian plasticity. These results are the first in vitro (as opposed to in silico demonstration of neural networks performing blind source separation, and the first formal demonstration of neuronal self-organization under the free energy principle.

A particle velocity based method for separating all multi incoherent sound sources

NARCIS (Netherlands)

Winkel, J.C.; Yntema, Doekle Reinder; Druyvesteyn, W.F.; de Bree, H.E.

2006-01-01

In this paper we present a method to separate the contributions of different uncorrelated sound sources to the total sound field. When the contribution of each sound source to the total sound field is known, techniques with array-applications like direct sound field measurements or inverse acoustics

Separation of zeros for source signature identification under reverberant path conditions.

Science.gov (United States)

Hasegawa, Tomomi; Tohyama, Mikio

2011-10-01

This paper presents an approach to distinguishing the zeros representing a sound source from those representing the transfer function on the basis of Lyon's residue-sign model. In machinery noise diagnostics, the source signature must be separated from observation records under reverberant path conditions. In numerical examples and an experimental piano-string vibration analysis, the modal responses could be synthesized by using clustered line-spectrum modeling. The modeling error represented the source signature subject to the source characteristics being given by a finite impulse response. The modeling error can be interpreted as a remainder function necessary for the zeros representing the source signature. © 2011 Acoustical Society of America

Development of the high temperature ion-source for the Grenoble electromagnetic isotope separator

International Nuclear Information System (INIS)

Bouriant, M.

1968-01-01

The production of high purity stable or radioactive isotopes (≥ 99.99 per cent) using electromagnetic separation require for equipment having a high resolving power. Besides, and in order to collect rare or short half-life isotopes, the efficiency of the ion-source must be high (η > 5 to 10 per cent). With this in view, the source built operates at high temperatures (2500-3000 C) and makes use of ionisation by electronic bombardment or of thermo-ionisation. A summary is given in the first part of this work on the essential characteristics of the isotope separator ion Sources; a diagram of the principle of the source built is then given together with its characteristics. In the second part are given the values of the resolving power and of the efficiency of the Grenoble isotope separator fitted with such a source. The resolving power measured at 10 per cent of the peak height is of the order of 200. At the first magnetic stage the efficiency is between 1 and 26 per cent for a range of elements evaporating between 200 and 3000 C. Thus equipped, the separator has for example given, at the first stage, 10 mg of 180 Hf at (99.69 ± 0.1) per cent corresponding to an enrichment coefficient of 580; recently 2 mg of 150 Nd at (99.996 ± 0.002) per cent corresponding to an enrichment coefficient of 4.2 x 10 5 has been obtained at the second stage. (author) [fr

Full-Scale Turbofan Engine Noise-Source Separation Using a Four-Signal Method

Science.gov (United States)

Hultgren, Lennart S.; Arechiga, Rene O.

2016-01-01

Contributions from the combustor to the overall propulsion noise of civilian transport aircraft are starting to become important due to turbofan design trends and expected advances in mitigation of other noise sources. During on-ground, static-engine acoustic tests, combustor noise is generally sub-dominant to other engine noise sources because of the absence of in-flight effects. Consequently, noise-source separation techniques are needed to extract combustor-noise information from the total noise signature in order to further progress. A novel four-signal source-separation method is applied to data from a static, full-scale engine test and compared to previous methods. The new method is, in a sense, a combination of two- and three-signal techniques and represents an attempt to alleviate some of the weaknesses of each of those approaches. This work is supported by the NASA Advanced Air Vehicles Program, Advanced Air Transport Technology Project, Aircraft Noise Reduction Subproject and the NASA Glenn Faculty Fellowship Program.

Factors influencing source separation intention and willingness to pay for improving waste management in Bangkok, Thailand

Directory of Open Access Journals (Sweden)

Sujitra Vassanadumrongdee

2018-03-01

Full Text Available Source separation for recycling has been recognized as a way to achieve sustainable municipal solid waste (MSW management. However, most developing countries including Thailand have been facing with lack of recycling facilities and low level of source separation practice. By employing questionnaire surveys, this study investigated Bangkok residents' source separation intention and willingness to pay (WTP for improving MSW service and recycling facilities (n = 1076. This research extended the theory of planned behavior to explore the effects of both internal and external factors. The survey highlighted perceived inconvenience and mistrust on MSW collection being major barriers to carrying out source separation in Bangkok. Promoting source separation at workplace may possibly create spill-over effect to people's intention to recycle their waste at home. Both subjective norms and knowledge on MSW situation were found to be a positive correlation with Bangkok residents' source separation intention and WTP (p < 0.001. Besides, the average WTP values are higher than the existing rate of waste collection service, which shows that Bangkok residents have preference for recycling programs. However, the WTP figures are still much lower than the average MSW management cost. These findings suggest that Bangkok Metropolitan Administration targets improving people knowledge on waste problems that could have adverse impact on the economy and well-being of Bangkok residents and improve its MSW collection service as these factors have positive influence on residents' WTP.

Back-trajectory modeling of high time-resolution air measurement data to separate nearby sources

Science.gov (United States)

Strategies to isolate air pollution contributions from sources is of interest as voluntary or regulatory measures are undertaken to reduce air pollution. When different sources are located in close proximity to one another and have similar emissions, separating source emissions ...

Life cycle assessment and costing of urine source separation: Focus on nonsteroidal anti-inflammatory drug removal.

Science.gov (United States)

Landry, Kelly A; Boyer, Treavor H

2016-11-15

Urine source separation has the potential to reduce pharmaceutical loading to the environment, while enhancing nutrient recovery. The focus of this life cycle assessment (LCA) was to evaluate the environmental impacts and economic costs to manage nonsteroidal anti-inflammatory drugs (NSAIDs) (i.e., diclofenac, ibuprofen, ketoprofen and naproxen) and nutrients in human urine. Urine source separation was compared with centralized wastewater treatment (WWT) (biological or upgraded with ozonation). The current treatment method (i.e., centralized biological WWT) was compared with hypothetical treatment scenarios (i.e., centralized biological WWT upgraded with ozonation, and urine source separation). Alternative urine source separation scenarios included varying collection and handling methods (i.e., collection by vacuum truck, vacuum sewer, or decentralized treatment), pharmaceuticals removal by ion-exchange, and struvite precipitation. Urine source separation scenarios had 90% lower environmental impact (based on the TRACI impact assessment method) compared with the centralized wastewater scenarios due to reduced potable water production for flush water, reduced electricity use at the wastewater treatment plant, and nutrient offsets from struvite precipitation. Despite the greatest reduction of pharmaceutical toxicity, centralized treatment upgraded with ozone had the greatest ecotoxicity impacts due to ozonation operation and infrastructure. Among urine source separation scenarios, decentralized treatment of urine and centralized treatment of urine collected by vacuum truck had negligible cost differences compared with centralized wastewater treatment. Centralized treatment of urine collected by vacuum sewer and centralized treatment with ozone cost 30% more compared with conventional wastewater treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Residents’ Preferences for Household Kitchen Waste Source Separation Services in Beijing: A Choice Experiment Approach

Directory of Open Access Journals (Sweden)

Yalin Yuan

2014-12-01

Full Text Available A source separation program for household kitchen waste has been in place in Beijing since 2010. However, the participation rate of residents is far from satisfactory. This study was carried out to identify residents’ preferences based on an improved management strategy for household kitchen waste source separation. We determine the preferences of residents in an ad hoc sample, according to their age level, for source separation services and their marginal willingness to accept compensation for the service attributes. We used a multinomial logit model to analyze the data, collected from 394 residents in Haidian and Dongcheng districts of Beijing City through a choice experiment. The results show there are differences of preferences on the services attributes between young, middle, and old age residents. Low compensation is not a major factor to promote young and middle age residents accept the proposed separation services. However, on average, most of them prefer services with frequent, evening, plastic bag attributes and without instructor. This study indicates that there is a potential for local government to improve the current separation services accordingly.

Rhythmic entrainment source separation: Optimizing analyses of neural responses to rhythmic sensory stimulation.

Science.gov (United States)

Cohen, Michael X; Gulbinaite, Rasa

2017-02-15

Steady-state evoked potentials (SSEPs) are rhythmic brain responses to rhythmic sensory stimulation, and are often used to study perceptual and attentional processes. We present a data analysis method for maximizing the signal-to-noise ratio of the narrow-band steady-state response in the frequency and time-frequency domains. The method, termed rhythmic entrainment source separation (RESS), is based on denoising source separation approaches that take advantage of the simultaneous but differential projection of neural activity to multiple electrodes or sensors. Our approach is a combination and extension of existing multivariate source separation methods. We demonstrate that RESS performs well on both simulated and empirical data, and outperforms conventional SSEP analysis methods based on selecting electrodes with the strongest SSEP response, as well as several other linear spatial filters. We also discuss the potential confound of overfitting, whereby the filter captures noise in absence of a signal. Matlab scripts are available to replicate and extend our simulations and methods. We conclude with some practical advice for optimizing SSEP data analyses and interpreting the results. Copyright © 2016 Elsevier Inc. All rights reserved.

Life Cycle Assessment of pretreatment technologies for anaerobic digestion of source-separated organic household waste

DEFF Research Database (Denmark)

Naroznova, Irina; Møller, Jacob; Scheutz, Charlotte

2013-01-01

The environmental performance of two pretreatment technologies for source-separated organic waste was compared using life cycle assessment (LCA). An innovative pulping process where source-separated organic waste is pulped with cold water forming a volatile solid rich biopulp was compared to a more...... including a number of non-toxic and toxic impact categories were assessed. No big difference in the overall performance of the two technologies was observed. The difference for the separate life cycle steps was, however, more pronounced. More efficient material transfer in the scenario with waste pulping...

Materials recovery system for source-separated noncombustible rubbish and bulky waste in Nishinomiya

Energy Technology Data Exchange (ETDEWEB)

Adachi, Yoshihiro

1987-01-01

Since 1980, the city of Nishinomiya has been recovering materials from source-separated non-combustible and bulky waste to reduce the amount of final disposal. Materials amounting to 33-39% of the throughput are recovered in the Shredding and Separation Facility, which consists of a manual separation system, a mechanical separation system, a shredder, a pair of shears and incinerators. The facility system is shown in order of processing of the waste. The secondary pollution control, safety equipment, instrumentation, etc., are also described. The recovery percentage and use of revenues are explained in detail.

Survival of enteric bacteria in source-separated human urine used ...

African Journals Online (AJOL)

MAKAYA

Urine in Pumpkin (Cucurbita maxima) Cultivation. Agric. Food Sci. 18:57-68. Pronk W, Koné D (2010). Options for urine treatment in developing countries. Desalination 251:360-368. Schönning C, Leeming R, Stenström TA (2002). Faecal contamination of source-separated human urine based on the content of faecal sterols ...

Efficient image enhancement using sparse source separation in the Retinex theory

Science.gov (United States)

Yoon, Jongsu; Choi, Jangwon; Choe, Yoonsik

2017-11-01

Color constancy is the feature of the human vision system (HVS) that ensures the relative constancy of the perceived color of objects under varying illumination conditions. The Retinex theory of machine vision systems is based on the HVS. Among Retinex algorithms, the physics-based algorithms are efficient; however, they generally do not satisfy the local characteristics of the original Retinex theory because they eliminate global illumination from their optimization. We apply the sparse source separation technique to the Retinex theory to present a physics-based algorithm that satisfies the locality characteristic of the original Retinex theory. Previous Retinex algorithms have limited use in image enhancement because the total variation Retinex results in an overly enhanced image and the sparse source separation Retinex cannot completely restore the original image. In contrast, our proposed method preserves the image edge and can very nearly replicate the original image without any special operation.

Blind source separation of ex-vivo aorta tissue multispectral images.

Science.gov (United States)

Galeano, July; Perez, Sandra; Montoya, Yonatan; Botina, Deivid; Garzón, Johnson

2015-05-01

Blind Source Separation methods (BSS) aim for the decomposition of a given signal in its main components or source signals. Those techniques have been widely used in the literature for the analysis of biomedical images, in order to extract the main components of an organ or tissue under study. The analysis of skin images for the extraction of melanin and hemoglobin is an example of the use of BSS. This paper presents a proof of concept of the use of source separation of ex-vivo aorta tissue multispectral Images. The images are acquired with an interference filter-based imaging system. The images are processed by means of two algorithms: Independent Components analysis and Non-negative Matrix Factorization. In both cases, it is possible to obtain maps that quantify the concentration of the main chromophores present in aortic tissue. Also, the algorithms allow for spectral absorbance of the main tissue components. Those spectral signatures were compared against the theoretical ones by using correlation coefficients. Those coefficients report values close to 0.9, which is a good estimator of the method's performance. Also, correlation coefficients lead to the identification of the concentration maps according to the evaluated chromophore. The results suggest that Multi/hyper-spectral systems together with image processing techniques is a potential tool for the analysis of cardiovascular tissue.

Resonance ionization laser ion sources for on-line isotope separators (invited)

International Nuclear Information System (INIS)

Marsh, B. A.

2014-01-01

A Resonance Ionization Laser Ion Source (RILIS) is today considered an essential component of the majority of Isotope Separator On Line (ISOL) facilities; there are seven laser ion sources currently operational at ISOL facilities worldwide and several more are under development. The ionization mechanism is a highly element selective multi-step resonance photo-absorption process that requires a specifically tailored laser configuration for each chemical element. For some isotopes, isomer selective ionization may even be achieved by exploiting the differences in hyperfine structures of an atomic transition for different nuclear spin states. For many radioactive ion beam experiments, laser resonance ionization is the only means of achieving an acceptable level of beam purity without compromising isotope yield. Furthermore, by performing element selection at the location of the ion source, the propagation of unwanted radioactivity downstream of the target assembly is reduced. Whilst advances in laser technology have improved the performance and reliability of laser ion sources and broadened the range of suitable commercially available laser systems, many recent developments have focused rather on the laser/atom interaction region in the quest for increased selectivity and/or improved spectral resolution. Much of the progress in this area has been achieved by decoupling the laser ionization from competing ionization processes through the use of a laser/atom interaction region that is physically separated from the target chamber. A new application of gas catcher laser ion source technology promises to expand the capabilities of projectile fragmentation facilities through the conversion of otherwise discarded reaction fragments into high-purity low-energy ion beams. A summary of recent RILIS developments and the current status of laser ion sources worldwide is presented

Iterative algorithm for joint zero diagonalization with application in blind source separation.

Science.gov (United States)

Zhang, Wei-Tao; Lou, Shun-Tian

2011-07-01

A new iterative algorithm for the nonunitary joint zero diagonalization of a set of matrices is proposed for blind source separation applications. On one hand, since the zero diagonalizer of the proposed algorithm is constructed iteratively by successive multiplications of an invertible matrix, the singular solutions that occur in the existing nonunitary iterative algorithms are naturally avoided. On the other hand, compared to the algebraic method for joint zero diagonalization, the proposed algorithm requires fewer matrices to be zero diagonalized to yield even better performance. The extension of the algorithm to the complex and nonsquare mixing cases is also addressed. Numerical simulations on both synthetic data and blind source separation using time-frequency distributions illustrate the performance of the algorithm and provide a comparison to the leading joint zero diagonalization schemes.

The Crowding-Out Effects of Garbage Fees and Voluntary Source Separation Programs on Waste Reduction: Evidence from China

Directory of Open Access Journals (Sweden)

Hongyun Han

2016-07-01

Full Text Available This paper examines how and to what degree government policies of garbage fees and voluntary source separation programs, with free indoor containers and garbage bags, can affect the effectiveness of municipal solid waste (MSW management, in the sense of achieving a desirable reduction of per capita MSW generation. Based on city-level panel data for years 1998–2012 in China, our empirical analysis indicates that per capita MSW generated is increasing with per capita disposable income, average household size, education levels of households, and the lagged per capita MSW. While both garbage fees and source separation programs have separately led to reductions in per capita waste generation, the interaction of the two policies has resulted in an increase in per capita waste generation due to the following crowding-out effects: Firstly, the positive effect of income dominates the negative effect of the garbage fee. Secondly, there are crowding-out effects of mandatory charging system and the subsidized voluntary source separation on per capita MSW generation. Thirdly, small subsidies and tax punishments have reduced the intrinsic motivation for voluntary source separation of MSW. Thus, compatible fee charging system, higher levels of subsidies, and well-designed public information and education campaigns are required to promote household waste source separation and reduction.

Vermicomposting of source-separated human faeces for nutrient recycling.

Science.gov (United States)

Yadav, Kunwar D; Tare, Vinod; Ahammed, M Mansoor

2010-01-01

The present study examined the suitability of vermicomposting technology for processing source-separated human faeces. Since the earthworm species Eisenia fetida could not survive in fresh faeces, modification in the physical characteristics of faeces was necessary before earthworms could be introduced to faeces. A preliminary study with six different combinations of faeces, soil and bulking material (vermicompost) in different layers was conducted to find out the best condition for biomass growth and reproduction of earthworms. The results indicated that SVFV combination (soil, vermicompost, faeces and vermicompost - bottom to top layers) was the best for earthworm biomass growth indicating the positive role of soil layer in earthworm biomass growth. Further studies with SVFV and VFV combinations, however, showed that soil layer did not enhance vermicompost production rate. Year-long study conducted with VFV combination to assess the quality and quantity of vermicompost produced showed an average vermicompost production rate of 0.30kg-cast/kg-worm/day. The vermicompost produced was mature as indicated by low dissolved organic carbon (2.4+/-0.43mg/g) and low oxygen uptake rate (0.15+/-0.09mg O(2)/g VS/h). Complete inactivation of total coliforms was noted during the study, which is one of the important objectives of human faeces processing. Results of the study thus indicated the potential of vermicomposting for processing of source-separated human faeces.

Investigation of gas discharge ion sources for on-line mass separation

International Nuclear Information System (INIS)

Kirchner, R.

1976-03-01

The development of efficient gas discharge ion sources with axial beam extraction for on-line mass separation is described. The aim of the investigation was to increase the ion source temperature, the lifetime and the ionisation yield in comparison to present low-pressure are discharge ion sources and to reduce the ion current density from usually 1 to 100 mA/cm 3 . In all ion sources the pressure range below the minimal ignition pressure of the arc discharge was investigated. As a result an ion source was developed which works at small changes in geometry and in electric device of a Nielsen source with high ionization yield (up to 50% for xenon) stabil and without ignition difficulties up to 10 -5 Torr. At a typical pressure of 3 x 10 -5 Torr ion current and ion current density are about 1 μA and 0.1 mA/cm 3 respectively besides high yield and a great emission aperture (diameter 1.2 mm). (orig.) [de

Stationary plasma source of heavy ions for imitating research at the separator

International Nuclear Information System (INIS)

Yuferov, V.B.; Sharyj, S.V.; Seroshtanov, V.A.

2008-01-01

The imitation gas mix choice for experimenting on the demonstration imitation separator have been grounded. The construction of plasma source is changed. The research of operating conditions and contrastive analysis of received characteristics have been carry out

Basic studies of a gas-jet-coupled ion source for on-line isotope separation

International Nuclear Information System (INIS)

Anderl, R.A.; Novick, V.J.; Greenwood, R.C.

1980-01-01

A hollow-cathode ion source was used in a gas-jet-coupled configuration to produce ion beams of fission products transported to it from a 252 Cf fission source. Solid aerosols of NaCl and Ag were used effectively as activity carriers in the gas-jet system. Flat-plate skimmers provided an effective coupling of the ion source to the gas jet. Ge(Li) spectrometric measurements of the activity deposited on an ion-beam collector relative to that deposited on a pre-skimmer collector were used to obtain separation efficiencies ranging from 0.1% to > 1% for Sr, Y, Tc, Te, Cs, Ba, Ce, Pr, Nd and Sm. The use of CCl 4 as a support gas resulted in a significant enhancement of the alkaline-earth and rare-earth separation efficiencies

How Many Separable Sources? Model Selection In Independent Components Analysis

DEFF Research Database (Denmark)

Woods, Roger P.; Hansen, Lars Kai; Strother, Stephen

2015-01-01

among potential model categories with differing numbers of Gaussian components. Based on simulation studies, the assumptions and approximations underlying the Akaike Information Criterion do not hold in this setting, even with a very large number of observations. Cross-validation is a suitable, though....../Principal Components Analysis (mixed ICA/PCA) model described here accommodates one or more Gaussian components in the independent components analysis model and uses principal components analysis to characterize contributions from this inseparable Gaussian subspace. Information theory can then be used to select from...... might otherwise be questionable. Failure of the Akaike Information Criterion in model selection also has relevance in traditional independent components analysis where all sources are assumed non-Gaussian....

Blind separation of positive sources by globally convergent gradient search.

Science.gov (United States)

Oja, Erkki; Plumbley, Mark

2004-09-01

The instantaneous noise-free linear mixing model in independent component analysis is largely a solved problem under the usual assumption of independent nongaussian sources and full column rank mixing matrix. However, with some prior information on the sources, like positivity, new analysis and perhaps simplified solution methods may yet become possible. In this letter, we consider the task of independent component analysis when the independent sources are known to be nonnegative and well grounded, which means that they have a nonzero pdf in the region of zero. It can be shown that in this case, the solution method is basically very simple: an orthogonal rotation of the whitened observation vector into nonnegative outputs will give a positive permutation of the original sources. We propose a cost function whose minimum coincides with nonnegativity and derive the gradient algorithm under the whitening constraint, under which the separating matrix is orthogonal. We further prove that in the Stiefel manifold of orthogonal matrices, the cost function is a Lyapunov function for the matrix gradient flow, implying global convergence. Thus, this algorithm is guaranteed to find the nonnegative well-grounded independent sources. The analysis is complemented by a numerical simulation, which illustrates the algorithm.

Concepts and Criteria for Blind Quantum Source Separation and Blind Quantum Process Tomography

Directory of Open Access Journals (Sweden)

Alain Deville

2017-07-01

Full Text Available Blind Source Separation (BSS is an active domain of Classical Information Processing, with well-identified methods and applications. The development of Quantum Information Processing has made possible the appearance of Blind Quantum Source Separation (BQSS, with a recent extension towards Blind Quantum Process Tomography (BQPT. This article investigates the use of several fundamental quantum concepts in the BQSS context and establishes properties already used without justification in that context. It mainly considers a pair of electron spins initially separately prepared in a pure state and then submitted to an undesired exchange coupling between these spins. Some consequences of the existence of the entanglement phenomenon, and of the probabilistic aspect of quantum measurements, upon BQSS solutions, are discussed. An unentanglement criterion is established for the state of an arbitrary qubit pair, expressed first with probability amplitudes and secondly with probabilities. The interest of using the concept of a random quantum state in the BQSS context is presented. It is stressed that the concept of statistical independence of the sources, widely used in classical BSS, should be used with care in BQSS, and possibly replaced by some disentanglement principle. It is shown that the coefficients of the development of any qubit pair pure state over the states of an orthonormal basis can be expressed with the probabilities of results in the measurements of well-chosen spin components.

A chemically selective laser ion source for the on-line isotope separation

International Nuclear Information System (INIS)

Scheerer, F.

1993-03-01

In this thesis a laser ion source is presented. In a hot chamber the atoms of the elements to be studied are resonantly by light of pulsed dye lasers, which are pumped by pulsed copper-vapor lasers with extremely high pulse repetition rate (ν rep ∼ 10 kHz), stepwise excited and ionized. By the storage of the atoms in a hot chamber and the high pulse repetition rate of the copper-vapor lasers beyond the required high efficiency (ε ∼ 10%) can be reached. First preparing measurements were performed at the off-line separator at CERN with the rare earth elements ytterbium and thulium. Starting from the results of these measurements further tests of the laser ion source were performed at the on-line separator with in a thick tantalum target produced neutron-deficient ytterbium isotopes. Under application of a time-of-flight mass spectrometer in Mainz an efficient excitation scheme on the resonance ionization of tin was found. This excitation scheme is condition for an experiment at the GSI for the production of the extremely neutron-deficient, short-lived nucleus 102 Sn. In the summer 1993 is as first application of the newly developed laser ion source at the PSB-ISOLDE at CERN an astrophysically relevant experiment for the nuclear spectroscopy of the neutron-rich silver isotopes 124-129 Ag is planned. This experiment can because of the lacking selectivity of conventional ion sources only be performed by means of the here presented laser ion source. The laser ion source shall at the PSB-ISOLDE 1993 also be applied for the selective ionization of manganese. (orig./HSI) [de

Property-close source separation of hazardous waste and waste electrical and electronic equipment - A Swedish case study

International Nuclear Information System (INIS)

Bernstad, Anna; Cour Jansen, Jes la; Aspegren, Henrik

2011-01-01

Through an agreement with EEE producers, Swedish municipalities are responsible for collection of hazardous waste and waste electrical and electronic equipment (WEEE). In most Swedish municipalities, collection of these waste fractions is concentrated to waste recycling centres where households can source-separate and deposit hazardous waste and WEEE free of charge. However, the centres are often located on the outskirts of city centres and cars are needed in order to use the facilities in most cases. A full-scale experiment was performed in a residential area in southern Sweden to evaluate effects of a system for property-close source separation of hazardous waste and WEEE. After the system was introduced, results show a clear reduction in the amount of hazardous waste and WEEE disposed of incorrectly amongst residual waste or dry recyclables. The systems resulted in a source separation ratio of 70 wt% for hazardous waste and 76 wt% in the case of WEEE. Results show that households in the study area were willing to increase source separation of hazardous waste and WEEE when accessibility was improved and that this and similar collection systems can play an important role in building up increasingly sustainable solid waste management systems.

Carbon dioxide capture and separation techniques for advanced power generation point sources

Energy Technology Data Exchange (ETDEWEB)

Pennline, H.W.; Luebke, D.R.; Morsi, B.I.; Heintz, Y.J.; Jones, K.L.; Ilconich, J.B.

2006-09-01

The capture/separation step for carbon dioxide (CO2) from large-point sources is a critical one with respect to the technical feasibility and cost of the overall carbon sequestration scenario. For large-point sources, such as those found in power generation, the carbon dioxide capture techniques being investigated by the in-house research area of the National Energy Technology Laboratory possess the potential for improved efficiency and costs as compared to more conventional technologies. The investigated techniques can have wide applications, but the research has focused on capture/separation of carbon dioxide from flue gas (postcombustion from fossil fuel-fired combustors) and from fuel gas (precombustion, such as integrated gasification combined cycle – IGCC). With respect to fuel gas applications, novel concepts are being developed in wet scrubbing with physical absorption; chemical absorption with solid sorbents; and separation by membranes. In one concept, a wet scrubbing technique is being investigated that uses a physical solvent process to remove CO2 from fuel gas of an IGCC system at elevated temperature and pressure. The need to define an ideal solvent has led to the study of the solubility and mass transfer properties of various solvents. Fabrication techniques and mechanistic studies for hybrid membranes separating CO2 from the fuel gas produced by coal gasification are also being performed. Membranes that consist of CO2-philic silanes incorporated into an alumina support or ionic liquids encapsulated into a polymeric substrate have been investigated for permeability and selectivity. An overview of two novel techniques is presented along with a research progress status of each technology.

Fate of pharmaceuticals in full-scale source separated sanitation system.

Science.gov (United States)

Butkovskyi, A; Hernandez Leal, L; Rijnaarts, H H M; Zeeman, G

2015-11-15

Removal of 14 pharmaceuticals and 3 of their transformation products was studied in a full-scale source separated sanitation system with separate collection and treatment of black water and grey water. Black water is treated in an up-flow anaerobic sludge blanket (UASB) reactor followed by oxygen-limited autotrophic nitrification-denitrification in a rotating biological contactor and struvite precipitation. Grey water is treated in an aerobic activated sludge process. Concentration of 10 pharmaceuticals and 2 transformation products in black water ranged between low μg/l to low mg/l. Additionally, 5 pharmaceuticals were also present in grey water in low μg/l range. Pharmaceutical influent loads were distributed over two streams, i.e. diclofenac was present for 70% in grey water, while the other compounds were predominantly associated to black water. Removal in the UASB reactor fed with black water exceeded 70% for 9 pharmaceuticals out of the 12 detected, with only two pharmaceuticals removed by sorption to sludge. Ibuprofen and the transformation product of naproxen, desmethylnaproxen, were removed in the rotating biological contactor. In contrast, only paracetamol removal exceeded 90% in the grey water treatment system while removal of other 7 pharmaceuticals was below 40% or even negative. The efficiency of pharmaceutical removal in the source separated sanitation system was compared with removal in the conventional sewage treatment plants. Furthermore, effluent concentrations of black water and grey water treatment systems were compared with predicted no-effect concentrations to assess toxicity of the effluent. Concentrations of diclofenac, ibuprofen and oxazepam in both effluents were higher than predicted no-effect concentrations, indicating the necessity of post-treatment. Ciprofloxacin, metoprolol and propranolol were found in UASB sludge in μg/g range, while pharmaceutical concentrations in struvite did not exceed the detection limits. Copyright © 2015

An approach for evaluating the effects of source separation on municipal solid waste management

Energy Technology Data Exchange (ETDEWEB)

Tanskanen, J.H. [Finnish Environment Institute, Helsinki (Finland)

2000-07-01

An approach was developed for integrated analysis of recovery rates, waste streams, costs and emissions of municipal solid waste management (MSWM). The approach differs from most earlier models used in the strategic planning of MSWM because of a comprehensive analysis of on-site collection systems of waste materials separated at source for recovery. As a result, the recovery rates and sizes of waste streams can be calculated on the basis of the characteristics of separation strategies instead of giving them as input data. The modelling concept developed can also be applied in other regions, municipalities and districts. This thesis consists of four case studies. Three of these were performed to test the approach developed and to evaluate the effects of separation on MSWM in Finland. In these case studies the approach was applied for modelling: (1) Finland's national separation strategy for municipal solid waste, (2) the effects of separation on MSWM systems in the Helsinki region and (3) the efficiency of various waste collection methods in the Helsinki region. The models developed for these three case studies are static and linear simulation models which were constructed in the format of an Excel spreadsheet. In addition, a new version of the original Swedish MIMES/Waste model was constructed and applied in one of the case studies. The case studies proved that the approach is an applicable tool for various research settings and circumstances in the strategic planning of MSWM. The following main results were obtained from the case studies: A high recovery rate level (around 70 %wt) can be achieved in MSWM without incineration; Central sorting of mixed waste must be included in Finland's national separation strategy in order to reach the recovery rate targets of 50 %wt (year 2000) and 70 %wt (year 2005) adopted for municipal solid waste in the National Waste Plan. The feasible source separation strategies result in recovery rates around 35-40 %wt with the

Blind Source Separation For Ion Mobility Spectra

International Nuclear Information System (INIS)

Marco, S.; Pomareda, V.; Pardo, A.; Kessler, M.; Goebel, J.; Mueller, G.

2009-01-01

Miniaturization is a powerful trend for smart chemical instrumentation in a diversity of applications. It is know that miniaturization in IMS leads to a degradation of the system characteristics. For the present work, we are interested in signal processing solutions to mitigate limitations introduced by limited drift tube length that basically involve a loss of chemical selectivity. While blind source separation techniques (BSS) are popular in other domains, their application for smart chemical instrumentation is limited. However, in some conditions, basically linearity, BSS may fully recover the concentration time evolution and the pure spectra with few underlying hypothesis. This is extremely helpful in conditions where non-expected chemical interferents may appear, or unwanted perturbations may pollute the spectra. SIMPLISMA has been advocated by Harrington et al. in several papers. However, more modern methods of BSS for bilinear decomposition with the restriction of positiveness have appeared in the last decade. In order to explore and compare the performances of those methods a series of experiments were performed.

Carbon Dioxide Capture and Separation Techniques for Gasification-based Power Generation Point Sources

Energy Technology Data Exchange (ETDEWEB)

Pennline, H.W.; Luebke, D.R.; Jones, K.L.; Morsi, B.I. (Univ. of Pittsburgh, PA); Heintz, Y.J. (Univ. of Pittsburgh, PA); Ilconich, J.B. (Parsons)

2007-06-01

The capture/separation step for carbon dioxide (CO2) from large-point sources is a critical one with respect to the technical feasibility and cost of the overall carbon sequestration scenario. For large-point sources, such as those found in power generation, the carbon dioxide capture techniques being investigated by the in-house research area of the National Energy Technology Laboratory possess the potential for improved efficiency and reduced costs as compared to more conventional technologies. The investigated techniques can have wide applications, but the research has focused on capture/separation of carbon dioxide from flue gas (post-combustion from fossil fuel-fired combustors) and from fuel gas (precombustion, such as integrated gasification combined cycle or IGCC). With respect to fuel gas applications, novel concepts are being developed in wet scrubbing with physical absorption; chemical absorption with solid sorbents; and separation by membranes. In one concept, a wet scrubbing technique is being investigated that uses a physical solvent process to remove CO2 from fuel gas of an IGCC system at elevated temperature and pressure. The need to define an ideal solvent has led to the study of the solubility and mass transfer properties of various solvents. Pertaining to another separation technology, fabrication techniques and mechanistic studies for membranes separating CO2 from the fuel gas produced by coal gasification are also being performed. Membranes that consist of CO2-philic ionic liquids encapsulated into a polymeric substrate have been investigated for permeability and selectivity. Finally, dry, regenerable processes based on sorbents are additional techniques for CO2 capture from fuel gas. An overview of these novel techniques is presented along with a research progress status of technologies related to membranes and physical solvents.

The management challenge for household waste in emerging economies like Brazil: realistic source separation and activation of reverse logistics.

Science.gov (United States)

Fehr, M

2014-09-01

Business opportunities in the household waste sector in emerging economies still evolve around the activities of bulk collection and tipping with an open material balance. This research, conducted in Brazil, pursued the objective of shifting opportunities from tipping to reverse logistics in order to close the balance. To do this, it illustrated how specific knowledge of sorted waste composition and reverse logistics operations can be used to determine realistic temporal and quantitative landfill diversion targets in an emerging economy context. Experimentation constructed and confirmed the recycling trilogy that consists of source separation, collection infrastructure and reverse logistics. The study on source separation demonstrated the vital difference between raw and sorted waste compositions. Raw waste contained 70% biodegradable and 30% inert matter. Source separation produced 47% biodegradable, 20% inert and 33% mixed material. The study on collection infrastructure developed the necessary receiving facilities. The study on reverse logistics identified private operators capable of collecting and processing all separated inert items. Recycling activities for biodegradable material were scarce and erratic. Only farmers would take the material as animal feed. No composting initiatives existed. The management challenge was identified as stimulating these activities in order to complete the trilogy and divert the 47% source-separated biodegradable discards from the landfills. © The Author(s) 2014.

A multilevel reuse system with source separation process for printing and dyeing wastewater treatment: A case study.

Science.gov (United States)

Wang, Rui; Jin, Xin; Wang, Ziyuan; Gu, Wantao; Wei, Zhechao; Huang, Yuanjie; Qiu, Zhuang; Jin, Pengkang

2018-01-01

This paper proposes a new system of multilevel reuse with source separation in printing and dyeing wastewater (PDWW) treatment in order to dramatically improve the water reuse rate to 35%. By analysing the characteristics of the sources and concentrations of pollutants produced in different printing and dyeing processes, special, highly, and less contaminated wastewaters (SCW, HCW, and LCW, respectively) were collected and treated separately. Specially, a large quantity of LCW was sequentially reused at multiple levels to meet the water quality requirements for different production processes. Based on this concept, a multilevel reuse system with a source separation process was established in a typical printing and dyeing enterprise. The water reuse rate increased dramatically to 62%, and the reclaimed water was reused in different printing and dyeing processes based on the water quality. This study provides promising leads in water management for wastewater reclamation. Copyright © 2017 Elsevier Ltd. All rights reserved.

A system dynamics model to evaluate effects of source separation of municipal solid waste management: A case of Bangkok, Thailand.

Science.gov (United States)

Sukholthaman, Pitchayanin; Sharp, Alice

2016-06-01

Municipal solid waste has been considered as one of the most immediate and serious problems confronting urban government in most developing and transitional economies. Providing solid waste performance highly depends on the effectiveness of waste collection and transportation process. Generally, this process involves a large amount of expenditures and has very complex and dynamic operational problems. Source separation has a major impact on effectiveness of waste management system as it causes significant changes in quantity and quality of waste reaching final disposal. To evaluate the impact of effective source separation on waste collection and transportation, this study adopts a decision support tool to comprehend cause-and-effect interactions of different variables in waste management system. A system dynamics model that envisages the relationships of source separation and effectiveness of waste management in Bangkok, Thailand is presented. Influential factors that affect waste separation attitudes are addressed; and the result of change in perception on waste separation is explained. The impacts of different separation rates on effectiveness of provided collection service are compared in six scenarios. 'Scenario 5' gives the most promising opportunities as 40% of residents are willing to conduct organic and recyclable waste separation. The results show that better service of waste collection and transportation, less monthly expense, extended landfill life, and satisfactory efficiency of the provided service at 60.48% will be achieved at the end of the simulation period. Implications of how to get public involved and conducted source separation are proposed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Blind Source Separation of Event-Related EEG/MEG.

Science.gov (United States)

Metsomaa, Johanna; Sarvas, Jukka; Ilmoniemi, Risto Juhani

2017-09-01

Blind source separation (BSS) can be used to decompose complex electroencephalography (EEG) or magnetoencephalography data into simpler components based on statistical assumptions without using a physical model. Applications include brain-computer interfaces, artifact removal, and identifying parallel neural processes. We wish to address the issue of applying BSS to event-related responses, which is challenging because of nonstationary data. We introduce a new BSS approach called momentary-uncorrelated component analysis (MUCA), which is tailored for event-related multitrial data. The method is based on approximate joint diagonalization of multiple covariance matrices estimated from the data at separate latencies. We further show how to extend the methodology for autocovariance matrices and how to apply BSS methods suitable for piecewise stationary data to event-related responses. We compared several BSS approaches by using simulated EEG as well as measured somatosensory and transcranial magnetic stimulation (TMS) evoked EEG. Among the compared methods, MUCA was the most tolerant one to noise, TMS artifacts, and other challenges in the data. With measured somatosensory data, over half of the estimated components were found to be similar by MUCA and independent component analysis. MUCA was also stable when tested with several input datasets. MUCA is based on simple assumptions, and the results suggest that MUCA is robust with nonideal data. Event-related responses and BSS are valuable and popular tools in neuroscience. Correctly designed BSS is an efficient way of identifying artifactual and neural processes from nonstationary event-related data.

Source Separation and Treament of Anthropogenic Urine (WERF Report INFR4SG09b)

Science.gov (United States)

Abstract: Anthropogenic urine, although only 1% of domestic wastewater flow, is responsible for 50-80% of the nutrients and a substantial portion of the pharmaceuticals and hormones present in the influent to wastewater treatment plants. Source separation and treatment of urine...

Instantaneous and Frequency-Warped Signal Processing Techniques for Auditory Source Separation.

Science.gov (United States)

Wang, Avery Li-Chun

This thesis summarizes several contributions to the areas of signal processing and auditory source separation. The philosophy of Frequency-Warped Signal Processing is introduced as a means for separating the AM and FM contributions to the bandwidth of a complex-valued, frequency-varying sinusoid p (n), transforming it into a signal with slowly-varying parameters. This transformation facilitates the removal of p (n) from an additive mixture while minimizing the amount of damage done to other signal components. The average winding rate of a complex-valued phasor is explored as an estimate of the instantaneous frequency. Theorems are provided showing the robustness of this measure. To implement frequency tracking, a Frequency-Locked Loop algorithm is introduced which uses the complex winding error to update its frequency estimate. The input signal is dynamically demodulated and filtered to extract the envelope. This envelope may then be remodulated to reconstruct the target partial, which may be subtracted from the original signal mixture to yield a new, quickly-adapting form of notch filtering. Enhancements to the basic tracker are made which, under certain conditions, attain the Cramer -Rao bound for the instantaneous frequency estimate. To improve tracking, the novel idea of Harmonic -Locked Loop tracking, using N harmonically constrained trackers, is introduced for tracking signals, such as voices and certain musical instruments. The estimated fundamental frequency is computed from a maximum-likelihood weighting of the N tracking estimates, making it highly robust. The result is that harmonic signals, such as voices, can be isolated from complex mixtures in the presence of other spectrally overlapping signals. Additionally, since phase information is preserved, the resynthesized harmonic signals may be removed from the original mixtures with relatively little damage to the residual signal. Finally, a new methodology is given for designing linear-phase FIR filters

Sources and speciation of heavy metals in municipal solid waste (MSW) and its effect on the separation technique

Energy Technology Data Exchange (ETDEWEB)

Biollaz, S; Ludwig, Ch; Stucki, S [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

1999-08-01

A literature search was carried out to determine sources and speciation of heavy metals in MSW. A combination of thermal and mechanical separation techniques is necessary to achieve the required high degrees of metal separation. Metallic goods should be separated mechanically, chemically bound heavy metals by a thermal process. (author) 1 fig., 1 tab., 6 refs.

Assume-Guarantee Abstraction Refinement Meets Hybrid Systems

Science.gov (United States)

Bogomolov, Sergiy; Frehse, Goran; Greitschus, Marius; Grosu, Radu; Pasareanu, Corina S.; Podelski, Andreas; Strump, Thomas

2014-01-01

Compositional verification techniques in the assume- guarantee style have been successfully applied to transition systems to efficiently reduce the search space by leveraging the compositional nature of the systems under consideration. We adapt these techniques to the domain of hybrid systems with affine dynamics. To build assumptions we introduce an abstraction based on location merging. We integrate the assume-guarantee style analysis with automatic abstraction refinement. We have implemented our approach in the symbolic hybrid model checker SpaceEx. The evaluation shows its practical potential. To the best of our knowledge, this is the first work combining assume-guarantee reasoning with automatic abstraction-refinement in the context of hybrid automata.

Separating oil from water

Energy Technology Data Exchange (ETDEWEB)

Webb, C

1991-04-11

The technology available to deal with oil spills has assumed many new faces in recent years. Methods of dealing with small-scale pollution in the process industries and vast oil slicks such as that in the Gulf have developed in parallel. The progress being made in finding new means of separating oil from water is reported and the relative merits of bioremediation, hydrocylones, horizontal separators and gas flotation are discussed. (author).

Source-based neurofeedback methods using EEG recordings: training altered brain activity in a functional brain source derived from blind source separation

Science.gov (United States)

White, David J.; Congedo, Marco; Ciorciari, Joseph

2014-01-01

A developing literature explores the use of neurofeedback in the treatment of a range of clinical conditions, particularly ADHD and epilepsy, whilst neurofeedback also provides an experimental tool for studying the functional significance of endogenous brain activity. A critical component of any neurofeedback method is the underlying physiological signal which forms the basis for the feedback. While the past decade has seen the emergence of fMRI-based protocols training spatially confined BOLD activity, traditional neurofeedback has utilized a small number of electrode sites on the scalp. As scalp EEG at a given electrode site reflects a linear mixture of activity from multiple brain sources and artifacts, efforts to successfully acquire some level of control over the signal may be confounded by these extraneous sources. Further, in the event of successful training, these traditional neurofeedback methods are likely influencing multiple brain regions and processes. The present work describes the use of source-based signal processing methods in EEG neurofeedback. The feasibility and potential utility of such methods were explored in an experiment training increased theta oscillatory activity in a source derived from Blind Source Separation (BSS) of EEG data obtained during completion of a complex cognitive task (spatial navigation). Learned increases in theta activity were observed in two of the four participants to complete 20 sessions of neurofeedback targeting this individually defined functional brain source. Source-based EEG neurofeedback methods using BSS may offer important advantages over traditional neurofeedback, by targeting the desired physiological signal in a more functionally and spatially specific manner. Having provided preliminary evidence of the feasibility of these methods, future work may study a range of clinically and experimentally relevant brain processes where individual brain sources may be targeted by source-based EEG neurofeedback. PMID

Treatment of Source-Separated Blackwater: A Decentralized Strategy for Nutrient Recovery towards a Circular Economy

OpenAIRE

Melesse Eshetu Moges; Daniel Todt; Arve Heistad

2018-01-01

Using a filter medium for organic matter removal and nutrient recovery from blackwater treatment is a novel concept and has not been investigated sufficiently to date. This paper demonstrates a combined blackwater treatment and nutrient-recovery strategy and establishes mechanisms for a more dependable source of plant nutrients aiming at a circular economy. Source-separated blackwater from a student dormitory was used as feedstock for a sludge blanket anaerobic-baffled reactor. The effluent f...

PWC-ICA: A Method for Stationary Ordered Blind Source Separation with Application to EEG

Science.gov (United States)

Bigdely-Shamlo, Nima; Mullen, Tim; Robbins, Kay

2016-01-01

Independent component analysis (ICA) is a class of algorithms widely applied to separate sources in EEG data. Most ICA approaches use optimization criteria derived from temporal statistical independence and are invariant with respect to the actual ordering of individual observations. We propose a method of mapping real signals into a complex vector space that takes into account the temporal order of signals and enforces certain mixing stationarity constraints. The resulting procedure, which we call Pairwise Complex Independent Component Analysis (PWC-ICA), performs the ICA in a complex setting and then reinterprets the results in the original observation space. We examine the performance of our candidate approach relative to several existing ICA algorithms for the blind source separation (BSS) problem on both real and simulated EEG data. On simulated data, PWC-ICA is often capable of achieving a better solution to the BSS problem than AMICA, Extended Infomax, or FastICA. On real data, the dipole interpretations of the BSS solutions discovered by PWC-ICA are physically plausible, are competitive with existing ICA approaches, and may represent sources undiscovered by other ICA methods. In conjunction with this paper, the authors have released a MATLAB toolbox that performs PWC-ICA on real, vector-valued signals. PMID:27340397

PWC-ICA: A Method for Stationary Ordered Blind Source Separation with Application to EEG.

Science.gov (United States)

Ball, Kenneth; Bigdely-Shamlo, Nima; Mullen, Tim; Robbins, Kay

2016-01-01

Independent component analysis (ICA) is a class of algorithms widely applied to separate sources in EEG data. Most ICA approaches use optimization criteria derived from temporal statistical independence and are invariant with respect to the actual ordering of individual observations. We propose a method of mapping real signals into a complex vector space that takes into account the temporal order of signals and enforces certain mixing stationarity constraints. The resulting procedure, which we call Pairwise Complex Independent Component Analysis (PWC-ICA), performs the ICA in a complex setting and then reinterprets the results in the original observation space. We examine the performance of our candidate approach relative to several existing ICA algorithms for the blind source separation (BSS) problem on both real and simulated EEG data. On simulated data, PWC-ICA is often capable of achieving a better solution to the BSS problem than AMICA, Extended Infomax, or FastICA. On real data, the dipole interpretations of the BSS solutions discovered by PWC-ICA are physically plausible, are competitive with existing ICA approaches, and may represent sources undiscovered by other ICA methods. In conjunction with this paper, the authors have released a MATLAB toolbox that performs PWC-ICA on real, vector-valued signals.

Blind Source Separation and Dynamic Fuzzy Neural Network for Fault Diagnosis in Machines

International Nuclear Information System (INIS)

Huang, Haifeng; Ouyang, Huajiang; Gao, Hongli

2015-01-01

Many assessment and detection methods are used to diagnose faults in machines. High accuracy in fault detection and diagnosis can be achieved by using numerical methods with noise-resistant properties. However, to some extent, noise always exists in measured data on real machines, which affects the identification results, especially in the diagnosis of early- stage faults. In view of this situation, a damage assessment method based on blind source separation and dynamic fuzzy neural network (DFNN) is presented to diagnose the early-stage machinery faults in this paper. In the processing of measurement signals, blind source separation is adopted to reduce noise. Then sensitive features of these faults are obtained by extracting low dimensional manifold characteristics from the signals. The model for fault diagnosis is established based on DFNN. Furthermore, on-line computation is accelerated by means of compressed sensing. Numerical vibration signals of ball screw fault modes are processed on the model for mechanical fault diagnosis and the results are in good agreement with the actual condition even at the early stage of fault development. This detection method is very useful in practice and feasible for early-stage fault diagnosis. (paper)

Life cycle and economic assessment of source-separated MSW collection with regard to greenhouse gas emissions: a case study in China.

Science.gov (United States)

Dong, Jun; Ni, Mingjiang; Chi, Yong; Zou, Daoan; Fu, Chao

2013-08-01

In China, the continuously increasing amount of municipal solid waste (MSW) has resulted in an urgent need for changing the current municipal solid waste management (MSWM) system based on mixed collection. A pilot program focusing on source-separated MSW collection was thus launched (2010) in Hangzhou, China, to lessen the related environmental loads. And greenhouse gas (GHG) emissions (Kyoto Protocol) are singled out in particular. This paper uses life cycle assessment modeling to evaluate the potential environmental improvement with regard to GHG emissions. The pre-existing MSWM system is assessed as baseline, while the source separation scenario is compared internally. Results show that 23 % GHG emissions can be decreased by source-separated collection compared with the base scenario. In addition, the use of composting and anaerobic digestion (AD) is suggested for further optimizing the management of food waste. 260.79, 82.21, and -86.21 thousand tonnes of GHG emissions are emitted from food waste landfill, composting, and AD, respectively, proving the emission reduction potential brought by advanced food waste treatment technologies. Realizing the fact, a modified MSWM system is proposed by taking AD as food waste substitution option, with additional 44 % GHG emissions saved than current source separation scenario. Moreover, a preliminary economic assessment is implemented. It is demonstrated that both source separation scenarios have a good cost reduction potential than mixed collection, with the proposed new system the most cost-effective one.

Electromagnetic separator of plasma

International Nuclear Information System (INIS)

Gasilin, V.V.; Nezovibatko, Yu.N.; Poklepach, G.S.; Shvets, O.M.; Taran, V.S.; Tereshin, V.I.

2005-01-01

The progress in the widespread utilization of the PVD methods is determined in many respects by the plasma quality and, therefore, the necessity of an application of plasma separators, in particular magnetic separators. One needs to note that traditional magnetic separators have a number of problems their using, namely their unwieldiness, the presence of the isolated cameras and so on. We have proposed, manufactured and investigated the simple separator of plasma that doesn't require using additional cameras. As a source of metallic plasma the standard cathode vaporizer in the installation 'BULAT 6' was in use. Plasma stream from the cathode flowed through the not protected by isolation spiral solenoid. The solenoid input (from the cathode side) was under floating potential. The solenoid output was connected to the autonomous power supply system. The solenoid was prepared with stride winding and 90 degree turn. The solenoid current was 20-90 A and the solenoid voltage with respect to the vessel (earth) was +15 V. In this case drifting charged particles could freely fly out from the interior solenoid region to its boundary. The glow of the turned flow of plasma was observed during the supplying of the cathode and the solenoid. Plasma flow was separated from the coils and extended along the axis of solenoid. One can assume that this device ensures radial electric with respect to the bulk of plasma (the diameter of the bulk of plasma is comparable with the cathode diameter), the toroidal magnetic field, produced by solenoid, was of an order of 20 Oe. Magnetic field strength was sufficient for the magnetization of electrons, but it was rather small for magnetizing the ions and charged micro-droplets. The experiments carried out with aluminum cathode on the deposition of coatings at the stainless steel substrate have shown the high effectiveness of this separator operation. Coatings without droplets were obtained also on the glass substrate with HF- displacement

An application of the theory of planned behaviour to study the influencing factors of participation in source separation of food waste

International Nuclear Information System (INIS)

Karim Ghani, Wan Azlina Wan Ab.; Rusli, Iffah Farizan; Biak, Dayang Radiah Awang; Idris, Azni

2013-01-01

Highlights: ► Theory of planned behaviour (TPB) has been conducted to identify the influencing factors for participation in source separation of food waste using self administered questionnaires. ► The findings suggested several implications for the development and implementation of waste separation at home programme. ► The analysis indicates that the attitude towards waste separation is determined as the main predictors where this in turn could be a significant predictor of the repondent’s actual food waste separation behaviour. ► To date, none of similar have been reported elsewhere and this finding will be beneficial to local Authorities as indicator in designing campaigns to promote the use of waste separation programmes to reinforce the positive attitudes. - Abstract: Tremendous increases in biodegradable (food waste) generation significantly impact the local authorities, who are responsible to manage, treat and dispose of this waste. The process of separation of food waste at its generation source is identified as effective means in reducing the amount food waste sent to landfill and can be reused as feedstock to downstream treatment processes namely composting or anaerobic digestion. However, these efforts will only succeed with positive attitudes and highly participations rate by the public towards the scheme. Thus, the social survey (using questionnaires) to analyse public’s view and influencing factors towards participation in source separation of food waste in households based on the theory of planned behaviour technique (TPB) was performed in June and July 2011 among selected staff in Universiti Putra Malaysia, Serdang, Selangor. The survey demonstrates that the public has positive intention in participating provided the opportunities, facilities and knowledge on waste separation at source are adequately prepared by the respective local authorities. Furthermore, good moral values and situational factors such as storage convenience and

An application of the theory of planned behaviour to study the influencing factors of participation in source separation of food waste

Energy Technology Data Exchange (ETDEWEB)

Karim Ghani, Wan Azlina Wan Ab., E-mail: wanaz@eng.upm.edu.my [Department of Chemical and Environmental Engineering, Faculty of Engineering, University Putra Malaysia, 43400 Serdang, Selangor Darul Ehsan (Malaysia); Rusli, Iffah Farizan, E-mail: iffahrusli@yahoo.com [Department of Chemical and Environmental Engineering, Faculty of Engineering, University Putra Malaysia, 43400 Serdang, Selangor Darul Ehsan (Malaysia); Biak, Dayang Radiah Awang, E-mail: dayang@eng.upm.edu.my [Department of Chemical and Environmental Engineering, Faculty of Engineering, University Putra Malaysia, 43400 Serdang, Selangor Darul Ehsan (Malaysia); Idris, Azni, E-mail: azni@eng.upm.edu.my [Department of Chemical and Environmental Engineering, Faculty of Engineering, University Putra Malaysia, 43400 Serdang, Selangor Darul Ehsan (Malaysia)

2013-05-15

Highlights: ► Theory of planned behaviour (TPB) has been conducted to identify the influencing factors for participation in source separation of food waste using self administered questionnaires. ► The findings suggested several implications for the development and implementation of waste separation at home programme. ► The analysis indicates that the attitude towards waste separation is determined as the main predictors where this in turn could be a significant predictor of the repondent’s actual food waste separation behaviour. ► To date, none of similar have been reported elsewhere and this finding will be beneficial to local Authorities as indicator in designing campaigns to promote the use of waste separation programmes to reinforce the positive attitudes. - Abstract: Tremendous increases in biodegradable (food waste) generation significantly impact the local authorities, who are responsible to manage, treat and dispose of this waste. The process of separation of food waste at its generation source is identified as effective means in reducing the amount food waste sent to landfill and can be reused as feedstock to downstream treatment processes namely composting or anaerobic digestion. However, these efforts will only succeed with positive attitudes and highly participations rate by the public towards the scheme. Thus, the social survey (using questionnaires) to analyse public’s view and influencing factors towards participation in source separation of food waste in households based on the theory of planned behaviour technique (TPB) was performed in June and July 2011 among selected staff in Universiti Putra Malaysia, Serdang, Selangor. The survey demonstrates that the public has positive intention in participating provided the opportunities, facilities and knowledge on waste separation at source are adequately prepared by the respective local authorities. Furthermore, good moral values and situational factors such as storage convenience and

Weight adjusted tensor method for blind separation of underdetermined mixtures of nonstationary sources

Czech Academy of Sciences Publication Activity Database

Tichavský, Petr; Koldovský, Zbyněk

2011-01-01

Roč. 59, č. 3 (2011), s. 1037-1047 ISSN 1053-587X R&D Projects: GA MŠk 1M0572; GA ČR GA102/09/1278 Institutional research plan: CEZ:AV0Z10750506 Keywords : blind source separation * tensor decomposition * Cramer-Rao lower bound Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 2.628, year: 2011 http://library.utia.cas.cz/separaty/2011/SI/tichavsky-0356666. pdf

Waste disposal and households' heterogeneity. Identifying factors shaping attitudes towards source-separated recycling in Bogotá, Colombia.

Science.gov (United States)

J Padilla, Alcides; Trujillo, Juan C

2018-04-01

Solid waste management in many cities of developing countries is not environmentally sustainable. People traditionally dispose of their solid waste in unsuitable urban areas like sidewalks and satellite dumpsites. This situation nowadays has become a serious public health problem in big Latin American conurbations. Among these densely-populated urban spaces, the Colombia's capital and main city stands out as a special case. In this study, we aim to identify the factors that shape the attitudes towards source-separated recycling among households in Bogotá. Using data from the Colombian Department of Statistics and Bogotá's multi-purpose survey, we estimated a multivariate Probit model. In general, our results show that the higher the household's socioeconomic class, the greater its effort for separating solid wastes. Likewise, our findings also allowed us to characterize household profiles regarding solid waste separation and considering each socioeconomic class. Among these profiles, we found that at lower socioeconomic classes, the attitudes towards solid waste separation are influenced by the use of Internet, the membership to an environmentalist organization, the level of education of the head of household and the homeownership. Hence, increasing the education levels within the poorest segment of the population, promoting affordable housing policies and facilitating Internet access for the vulnerable population could reinforce households' attitudes towards a greater source-separated recycling effort. Copyright © 2017 Elsevier Ltd. All rights reserved.

Separating Underdetermined Convolutive Speech Mixtures

DEFF Research Database (Denmark)

Pedersen, Michael Syskind; Wang, DeLiang; Larsen, Jan

2006-01-01

a method for underdetermined blind source separation of convolutive mixtures. The proposed framework is applicable for separation of instantaneous as well as convolutive speech mixtures. It is possible to iteratively extract each speech signal from the mixture by combining blind source separation...

Blind source separation analysis of PET dynamic data: a simple method with exciting MR-PET applications

Energy Technology Data Exchange (ETDEWEB)

Oros-Peusquens, Ana-Maria; Silva, Nuno da [Institute of Neuroscience and Medicine, Forschungszentrum Jülich GmbH, 52425 Jülich (Germany); Weiss, Carolin [Department of Neurosurgery, University Hospital Cologne, 50924 Cologne (Germany); Stoffels, Gabrielle; Herzog, Hans; Langen, Karl J [Institute of Neuroscience and Medicine, Forschungszentrum Jülich GmbH, 52425 Jülich (Germany); Shah, N Jon [Institute of Neuroscience and Medicine, Forschungszentrum Jülich GmbH, 52425 Jülich (Germany); Jülich-Aachen Research Alliance (JARA) - Section JARA-Brain RWTH Aachen University, 52074 Aachen (Germany)

2014-07-29

Denoising of dynamic PET data improves parameter imaging by PET and is gaining momentum. This contribution describes an analysis of dynamic PET data by blind source separation methods and comparison of the results with MR-based brain properties.

Generation of dynamo waves by spatially separated sources in the Earth and other celestial bodies

Science.gov (United States)

Popova, E.

2017-12-01

The amplitude and the spatial configuration of the planetary and stellar magnetic field can changing over the years. Celestial bodies can have cyclic, chaotic or unchanging in time magnetic activity which is connected with a dynamo mechanism. This mechanism is based on the consideration of the joint influence of the alpha-effect and differential rotation. Dynamo sources can be located at different depths (active layers) of the celestial body and can have different intensities. Application of this concept allows us to get different forms of solutions and some of which can include wave propagating inside the celestial body. We analytically showed that in the case of spatially separated sources of magnetic field each source generates a wave whose frequency depends on the physical parameters of its source. We estimated parameters of sources required for the generation nondecaying waves. We discus structure of such sources and matter motion (including meridional circulation) in the liquid outer core of the Earth and active layers of other celestial bodies.

Estimation of Input Function from Dynamic PET Brain Data Using Bayesian Blind Source Separation

Czech Academy of Sciences Publication Activity Database

Tichý, Ondřej; Šmídl, Václav

2015-01-01

Roč. 12, č. 4 (2015), s. 1273-1287 ISSN 1820-0214 R&D Projects: GA ČR GA13-29225S Institutional support: RVO:67985556 Keywords : blind source separation * Variational Bayes method * dynamic PET * input function * deconvolution Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 0.623, year: 2015 http://library.utia.cas.cz/separaty/2015/AS/tichy-0450509.pdf

Separation of uranium isotopes

International Nuclear Information System (INIS)

Porter, J.T.

1980-01-01

Methods and apparatus are disclosed for separation of uranium isotopes by selective isotopic excitation of photochemically reactive uranyl salt source material at cryogenic temperatures, followed by chemical separation of selectively photochemically reduced U+4 thereby produced from remaining uranyl source material

A robust physiology-based source separation method for QRS detection in low amplitude fetal ECG recordings

International Nuclear Information System (INIS)

Vullings, R; Bergmans, J W M; Peters, C H L; Hermans, M J M; Wijn, P F F; Oei, S G

2010-01-01

The use of the non-invasively obtained fetal electrocardiogram (ECG) in fetal monitoring is complicated by the low signal-to-noise ratio (SNR) of ECG signals. Even after removal of the predominant interference (i.e. the maternal ECG), the SNR is generally too low for medical diagnostics, and hence additional signal processing is still required. To this end, several methods for exploiting the spatial correlation of multi-channel fetal ECG recordings from the maternal abdomen have been proposed in the literature, of which principal component analysis (PCA) and independent component analysis (ICA) are the most prominent. Both PCA and ICA, however, suffer from the drawback that they are blind source separation (BSS) techniques and as such suboptimum in that they do not consider a priori knowledge on the abdominal electrode configuration and fetal heart activity. In this paper we propose a source separation technique that is based on the physiology of the fetal heart and on the knowledge of the electrode configuration. This technique operates by calculating the spatial fetal vectorcardiogram (VCG) and approximating the VCG for several overlayed heartbeats by an ellipse. By subsequently projecting the VCG onto the long axis of this ellipse, a source signal of the fetal ECG can be obtained. To evaluate the developed technique, its performance is compared to that of both PCA and ICA and to that of augmented versions of these techniques (aPCA and aICA; PCA and ICA applied on preprocessed signals) in generating a fetal ECG source signal with enhanced SNR that can be used to detect fetal QRS complexes. The evaluation shows that the developed source separation technique performs slightly better than aPCA and aICA and outperforms PCA and ICA and has the main advantage that, with respect to aPCA/PCA and aICA/ICA, it performs more robustly. This advantage renders it favorable for employment in automated, real-time fetal monitoring applications

Separation of simultaneous sources using a structural-oriented median filter in the flattened dimension

Science.gov (United States)

Gan, Shuwei; Wang, Shoudong; Chen, Yangkang; Chen, Xiaohong; Xiang, Kui

2016-01-01

Simultaneous-source shooting can help tremendously shorten the acquisition period and improve the quality of seismic data for better subsalt seismic imaging, but at the expense of introducing strong interference (blending noise) to the acquired seismic data. We propose to use a structural-oriented median filter to attenuate the blending noise along the structural direction of seismic profiles. The principle of the proposed approach is to first flatten the seismic record in local spatial windows and then to apply a traditional median filter (MF) to the third flattened dimension. The key component of the proposed approach is the estimation of the local slope, which can be calculated by first scanning the NMO velocity and then transferring the velocity to the local slope. Both synthetic and field data examples show that the proposed approach can successfully separate the simultaneous-source data into individual sources. We provide an open-source toy example to better demonstratethe proposed methodology.

Use of oleaginous plants in phytotreatment of grey water and yellow water from source separation of sewage.

Science.gov (United States)

Lavagnolo, Maria Cristina; Malagoli, Mario; Alibardi, Luca; Garbo, Francesco; Pivato, Alberto; Cossu, Raffaello

2017-05-01

Efficient and economic reuse of waste is one of the pillars of modern environmental engineering. In the field of domestic sewage management, source separation of yellow (urine), brown (faecal matter) and grey waters aims to recover the organic substances concentrated in brown water, the nutrients (nitrogen and phosphorous) in the urine and to ensure an easier treatment and recycling of grey waters. With the objective of emphasizing the potential of recovery of resources from sewage management, a lab-scale research study was carried out at the University of Padova in order to evaluate the performances of oleaginous plants (suitable for biodiesel production) in the phytotreatment of source separated yellow and grey waters. The plant species used were Brassica napus (rapeseed), Glycine max (soybean) and Helianthus annuus (sunflower). Phytotreatment tests were carried out using 20L pots. Different testing runs were performed at an increasing nitrogen concentration in the feedstock. The results proved that oleaginous species can conveniently be used for the phytotreatment of grey and yellow waters from source separation of domestic sewage, displaying high removal efficiencies of nutrients and organic substances (nitrogen>80%; phosphorous >90%; COD nearly 90%). No inhibition was registered in the growth of plants irrigated with different mixtures of yellow and grey waters, where the characteristics of the two streams were reciprocally and beneficially integrated. Copyright © 2016. Published by Elsevier B.V.

Chemical characteristics and methane potentials of source-separated and pre-treated organic municipal solid waste

DEFF Research Database (Denmark)

Hansen, Trine Lund; Svärd, Å; Angelidaki, Irini

2003-01-01

A research project has investigated the biogas potential of pre-screened source-separated organic waste. Wastes from five Danish cities have been pre-treated by three methods: screw press; disc screen; and shredder and magnet. This paper outlines the sampling procedure used, the chemical...... composition of the wastes and the estimated methane potentials....

Blind source separation based on time-frequency morphological characteristics for rigid acoustic scattering by underwater objects

Science.gov (United States)

Yang, Yang; Li, Xiukun

2016-06-01

Separation of the components of rigid acoustic scattering by underwater objects is essential in obtaining the structural characteristics of such objects. To overcome the problem of rigid structures appearing to have the same spectral structure in the time domain, time-frequency Blind Source Separation (BSS) can be used in combination with image morphology to separate the rigid scattering components of different objects. Based on a highlight model, the separation of the rigid scattering structure of objects with time-frequency distribution is deduced. Using a morphological filter, different characteristics in a Wigner-Ville Distribution (WVD) observed for single auto term and cross terms can be simplified to remove any cross-term interference. By selecting time and frequency points of the auto terms signal, the accuracy of BSS can be improved. An experimental simulation has been used, with changes in the pulse width of the transmitted signal, the relative amplitude and the time delay parameter, in order to analyzing the feasibility of this new method. Simulation results show that the new method is not only able to separate rigid scattering components, but can also separate the components when elastic scattering and rigid scattering exist at the same time. Experimental results confirm that the new method can be used in separating the rigid scattering structure of underwater objects.

System identification through nonstationary data using Time-Frequency Blind Source Separation

Science.gov (United States)

Guo, Yanlin; Kareem, Ahsan

2016-06-01

Classical output-only system identification (SI) methods are based on the assumption of stationarity of the system response. However, measured response of buildings and bridges is usually non-stationary due to strong winds (e.g. typhoon, and thunder storm etc.), earthquakes and time-varying vehicle motions. Accordingly, the response data may have time-varying frequency contents and/or overlapping of modal frequencies due to non-stationary colored excitation. This renders traditional methods problematic for modal separation and identification. To address these challenges, a new SI technique based on Time-Frequency Blind Source Separation (TFBSS) is proposed. By selectively utilizing "effective" information in local regions of the time-frequency plane, where only one mode contributes to energy, the proposed technique can successfully identify mode shapes and recover modal responses from the non-stationary response where the traditional SI methods often encounter difficulties. This technique can also handle response with closely spaced modes which is a well-known challenge for the identification of large-scale structures. Based on the separated modal responses, frequency and damping can be easily identified using SI methods based on a single degree of freedom (SDOF) system. In addition to the exclusive advantage of handling non-stationary data and closely spaced modes, the proposed technique also benefits from the absence of the end effects and low sensitivity to noise in modal separation. The efficacy of the proposed technique is demonstrated using several simulation based studies, and compared to the popular Second-Order Blind Identification (SOBI) scheme. It is also noted that even some non-stationary response data can be analyzed by the stationary method SOBI. This paper also delineates non-stationary cases where SOBI and the proposed scheme perform comparably and highlights cases where the proposed approach is more advantageous. Finally, the performance of the

Electron drag in ferromagnetic structures separated by an insulating interface

Science.gov (United States)

Kozub, V. I.; Muradov, M. I.; Galperin, Y. M.

2018-06-01

We consider electron drag in a system of two ferromagnetic layers separated by an insulating interface. The source of it is expected to be magnon-electron interactions. Namely, we assume that the external voltage is applied to the "active" layer stimulating electric current through this layer. In its turn, the scattering of the current-carrying electrons by magnons leads to a magnon drag current within this layer. The 3-magnons interactions between magnons in the two layers (being of non-local nature) lead to magnon drag within the "passive" layer which, correspondingly, produce electron drag current via processes of magnon-electron scattering. We estimate the drag current and compare it to the phonon-induced one.

MAP-Based Underdetermined Blind Source Separation of Convolutive Mixtures by Hierarchical Clustering and -Norm Minimization

Directory of Open Access Journals (Sweden)

Kellermann Walter

2007-01-01

Full Text Available We address the problem of underdetermined BSS. While most previous approaches are designed for instantaneous mixtures, we propose a time-frequency-domain algorithm for convolutive mixtures. We adopt a two-step method based on a general maximum a posteriori (MAP approach. In the first step, we estimate the mixing matrix based on hierarchical clustering, assuming that the source signals are sufficiently sparse. The algorithm works directly on the complex-valued data in the time-frequency domain and shows better convergence than algorithms based on self-organizing maps. The assumption of Laplacian priors for the source signals in the second step leads to an algorithm for estimating the source signals. It involves the -norm minimization of complex numbers because of the use of the time-frequency-domain approach. We compare a combinatorial approach initially designed for real numbers with a second-order cone programming (SOCP approach designed for complex numbers. We found that although the former approach is not theoretically justified for complex numbers, its results are comparable to, or even better than, the SOCP solution. The advantage is a lower computational cost for problems with low input/output dimensions.

In vivo time-gated diffuse correlation spectroscopy at quasi-null source-detector separation.

Science.gov (United States)

Pagliazzi, M; Sekar, S Konugolu Venkata; Di Sieno, L; Colombo, L; Durduran, T; Contini, D; Torricelli, A; Pifferi, A; Mora, A Dalla

2018-06-01

We demonstrate time domain diffuse correlation spectroscopy at quasi-null source-detector separation by using a fast time-gated single-photon avalanche diode without the need of time-tagging electronics. This approach allows for increased photon collection, simplified real-time instrumentation, and reduced probe dimensions. Depth discriminating, quasi-null distance measurement of blood flow in a human subject is presented. We envision the miniaturization and integration of matrices of optical sensors of increased spatial resolution and the enhancement of the contrast of local blood flow changes.

S values for selected radionuclides and organs with the heart wall and heart contents as source organs

International Nuclear Information System (INIS)

Coffey, J.L.; Watson, E.E.

1981-01-01

The generalized heart model of MIRD Pamphlet No. 5, Revised has no separation of heart wall from heart contents, and no phi values were listed for heart as either a source or target organ. Because of this, the heart model of the heterogeneous phantom for dosimetry calculations was revised and a description of this model and specific absorbed fractions will be published in MIRD Pamphlet No. 13. The purpose of this study is to use the specific absorbed fractions from MIRD-13 and decay scheme data to produce tables of S values (absorbed dose per unit cumulated activity) for selected radionuclides with the heart wall and heart contents as the source organs. As in the MIRD reports the activity is assumed to be uniformly distributed in the source organs. The phi values for the photon energies of a given radionuclide were found by lineraly interpolating between the energies listed in MIRD-13. When the source and target are the same, all nonpenetrating radiations are assumed to be absorbed in the organ in which they originate. For organs with walls and with the contents as the source, the dose to the wall from nonpenetrating radiations is assumed to be half of the dose to the contents

Perturbed invariant subspaces and approximate generalized functional variable separation solution for nonlinear diffusion-convection equations with weak source

Science.gov (United States)

Xia, Ya-Rong; Zhang, Shun-Li; Xin, Xiang-Peng

2018-03-01

In this paper, we propose the concept of the perturbed invariant subspaces (PISs), and study the approximate generalized functional variable separation solution for the nonlinear diffusion-convection equation with weak source by the approximate generalized conditional symmetries (AGCSs) related to the PISs. Complete classification of the perturbed equations which admit the approximate generalized functional separable solutions (AGFSSs) is obtained. As a consequence, some AGFSSs to the resulting equations are explicitly constructed by way of examples.

UWIS isotope separator

Energy Technology Data Exchange (ETDEWEB)

Wojtasiewicz, A. [Warsaw Univ., Inst. of Experimental Physics, Nuclear Physics Div., Warsaw (Poland)

1997-12-31

Since 1995 the University of Warsaw Isotope Separator group has participated in the ISOL/IGISOL project at the Heavy Ion Cyclotron. This project consists in installation of an isotope separator (on line with cyclotron heavy ion beam) with a hot plasma ion source (ISOL system) and/or with an ion guide source (IGISOL system). In the report the short description of the present status of the project is presented. 2 figs, 10 refs.

Sources of variability among replicate samples separated by two-dimensional gel electrophoresis.

Science.gov (United States)

Bland, Alison M; Janech, Michael G; Almeida, Jonas S; Arthur, John M

2010-04-01

Two-dimensional gel electrophoresis (2DE) offers high-resolution separation for intact proteins. However, variability in the appearance of spots can limit the ability to identify true differences between conditions. Variability can occur at a number of levels. Individual samples can differ because of biological variability. Technical variability can occur during protein extraction, processing, or storage. Another potential source of variability occurs during analysis of the gels and is not a result of any of the causes of variability named above. We performed a study designed to focus only on the variability caused by analysis. We separated three aliquots of rat left ventricle and analyzed differences in protein abundance on the replicate 2D gels. As the samples loaded on each gel were identical, differences in protein abundance are caused by variability in separation or interpretation of the gels. Protein spots were compared across gels by quantile values to determine differences. Fourteen percent of spots had a maximum difference in intensity of 0.4 quantile values or more between replicates. We then looked individually at the spots to determine the cause of differences between the measured intensities. Reasons for differences were: failure to identify a spot (59%), differences in spot boundaries (13%), difference in the peak height (6%), and a combination of these factors (21). This study demonstrates that spot identification and characterization make major contributions to variability seen with 2DE. Methods to highlight why measured protein spot abundance is different could reduce these errors.

An application of the theory of planned behaviour to study the influencing factors of participation in source separation of food waste.

Science.gov (United States)

Karim Ghani, Wan Azlina Wan Ab; Rusli, Iffah Farizan; Biak, Dayang Radiah Awang; Idris, Azni

2013-05-01

Tremendous increases in biodegradable (food waste) generation significantly impact the local authorities, who are responsible to manage, treat and dispose of this waste. The process of separation of food waste at its generation source is identified as effective means in reducing the amount food waste sent to landfill and can be reused as feedstock to downstream treatment processes namely composting or anaerobic digestion. However, these efforts will only succeed with positive attitudes and highly participations rate by the public towards the scheme. Thus, the social survey (using questionnaires) to analyse public's view and influencing factors towards participation in source separation of food waste in households based on the theory of planned behaviour technique (TPB) was performed in June and July 2011 among selected staff in Universiti Putra Malaysia, Serdang, Selangor. The survey demonstrates that the public has positive intention in participating provided the opportunities, facilities and knowledge on waste separation at source are adequately prepared by the respective local authorities. Furthermore, good moral values and situational factors such as storage convenience and collection times are also encouraged public's involvement and consequently, the participations rate. The findings from this study may provide useful indicator to the waste management authorities in Malaysia in identifying mechanisms for future development and implementation of food waste source separation activities in household programmes and communication campaign which advocate the use of these programmes. Copyright © 2012 Elsevier Ltd. All rights reserved.

Atmosphere-entry behavior of a modular, disk-shaped, isotope heat source.

Science.gov (United States)

Vorreiter, J. W.; Pitts, W. C.; Stine, H. A.; Burns, J. J.

1973-01-01

The authors have studied the entry and impact behavior of an isotope heat source for space nuclear power that disassembles into a number of modules which would enter the earth's atmosphere separately if a flight aborted. These modules are disk-shaped units, each with its own reentry heat shield and protective impact container. In normal operation, the disk modules are stacked inside the generator, but during a reentry abort they separate and fly as individual units of low ballistic coefficient. Flight tests at hypersonic speeds have confirmed that a stack of disks will separate and assume a flat-forward mode of flight. Free-fall tests of single disks have demonstrated a nominal impact velocity of 30 m/sec at sea level for a practical range of ballistic coefficients.

Online Artifact Removal for Brain-Computer Interfaces Using Support Vector Machines and Blind Source Separation

OpenAIRE

Halder, Sebastian; Bensch, Michael; Mellinger, Jürgen; Bogdan, Martin; Kübler, Andrea; Birbaumer, Niels; Rosenstiel, Wolfgang

2007-01-01

We propose a combination of blind source separation (BSS) and independent component analysis (ICA) (signal decomposition into artifacts and nonartifacts) with support vector machines (SVMs) (automatic classification) that are designed for online usage. In order to select a suitable BSS/ICA method, three ICA algorithms (JADE, Infomax, and FastICA) and one BSS algorithm (AMUSE) are evaluated to determine their ability to isolate electromyographic (EMG) and electrooculographic...

Depth sensitivity and source-detector separations for near infrared spectroscopy based on the Colin27 brain template.

Directory of Open Access Journals (Sweden)

Gary E Strangman

Full Text Available Understanding the spatial and depth sensitivity of non-invasive near-infrared spectroscopy (NIRS measurements to brain tissue-i.e., near-infrared neuromonitoring (NIN - is essential for designing experiments as well as interpreting research findings. However, a thorough characterization of such sensitivity in realistic head models has remained unavailable. In this study, we conducted 3,555 Monte Carlo (MC simulations to densely cover the scalp of a well-characterized, adult male template brain (Colin27. We sought to evaluate: (i the spatial sensitivity profile of NIRS to brain tissue as a function of source-detector separation, (ii the NIRS sensitivity to brain tissue as a function of depth in this realistic and complex head model, and (iii the effect of NIRS instrument sensitivity on detecting brain activation. We found that increasing the source-detector (SD separation from 20 to 65 mm provides monotonic increases in sensitivity to brain tissue. For every 10 mm increase in SD separation (up to ~45 mm, sensitivity to gray matter increased an additional 4%. Our analyses also demonstrate that sensitivity in depth (S decreases exponentially, with a "rule-of-thumb" formula S=0.75*0.85(depth. Thus, while the depth sensitivity of NIRS is not strictly limited, NIN signals in adult humans are strongly biased towards the outermost 10-15 mm of intracranial space. These general results, along with the detailed quantitation of sensitivity estimates around the head, can provide detailed guidance for interpreting the likely sources of NIRS signals, as well as help NIRS investigators design and plan better NIRS experiments, head probes and instruments.

Isotope separations using chromatographic methods

International Nuclear Information System (INIS)

Leseticky, L.

1985-01-01

A survey is given of chromatographic separations of compounds only differing in isotope composition. Isotope effects on physical properties which allow chromatographic separation (vapour tension, adsorption heat, partition coefficient) are very small, with the exception of the simplest molecules. Therefore, separation factors only assume the value of several per cent. From this ensues the necessity of using columns which are specially and very carefully prepared and have a separation efficiency of the order of 10 4 theoretical plates. Briefly discussed is liquid chromatography on ion exchangers which with a varied degree of success was used for separating simple inorganic compounds or ions. Ion exchange chromatography of amino acids labelled with tritium, and chromatography of tritium labelled steroids also provided only a certain degree of separation. A detailed analysis is presented of gas chromatography separation of various deuterium and tritium labelled low-molecular compounds, to which a number of studies has been devoted in the literature. Very promising is the method of complexation gas chromatography based on the reversible formation of a complex of the ligand (the compound being separated) and the compound of the (transition) metal as the steady-state phase. (author)

Separating contributions from natural and anthropogenic sources in atmospheric methane from the Black Sea region, Romania

International Nuclear Information System (INIS)

Cuna, Stela; Pendall, Elise; Miller, John B.; Tans, Pieter P.; Dlugokencky, Ed; White, James W.C.

2008-01-01

The Danube Delta-Black Sea region of Romania is an important wetland, and this preliminary study evaluates the significance of this region as a source of atmospheric CH 4 . Measurements of the mixing ratio and δ 13 C in CH 4 are reported from air and water samples collected at eight sites in the Danube Delta. High mixing ratios of CH 4 were found in air (2500-14,000 ppb) and dissolved in water samples (∼1-10 μmol L -1 ), demonstrating that the Danube Delta is an important natural source of CH 4 . The intercepts on Keeling plots of about -62 per mille show that the main source of CH 4 in this region is microbial, probably resulting primarily from acetate fermentation. Atmospheric CH 4 and CO data from the NOAA/ESRL (National Oceanic and Atmospheric Administration/Earth System Research Laboratory) were used to make a preliminary estimate of biogenic CH 4 at the Black Sea sampling site at Constanta (BSC). These data were used to calculate ratios of CH 4 /CO in air samples, and using an assumed CH 4 /CO anthropogenic emissions ratio of 0.6, fossil fuel emissions at BSC were estimated. Biogenic CH 4 emissions were then estimated by a simple mass balance approach. Keeling plots of well-mixed air from the BSC site suggested a stronger wetland source in summer and a stronger fossil fuel source in winter

Ion-source dependence of the distributions of internuclear separations in 2-MeV HeH+ beams

International Nuclear Information System (INIS)

Kanter, E.P.; Gemmell, D.S.; Plesser, I.; Vager, Z.

1981-01-01

Experiments involving the use of MeV molecular-ion beams have yielded new information on atomic collisions in solids. A central part of the analyses of such experiments is a knowledge of the distribution of internuclear separations contained in the incident beam. In an attempt to determine how these distributions depend on ion-source gas conditions, we have studied foil-induced dissociations of H 2+ , H 3+ , HeH + , and OH 2+ ions. Although changes of ion-source gas compositions and pressure were found to have no measurable influence on the vibrational state populations of the beams reaching our target, for HeH + we found that beams produced in our rf source were vibrationally hotter than beams produced in a duoplasmatron. This was also seen in studies of neutral fragments and transmitted molecules

Anaerobic treatment as a core technology for energy, nutrients and water from source-separated domestic waste(water)

NARCIS (Netherlands)

Zeeman, G.; Kujawa, K.; Mes, de T.Z.D.; Graaff, de M.S.; Abu-Ghunmi, L.N.A.H.; Mels, A.R.; Meulman, B.; Temmink, B.G.; Buisman, C.J.N.; Lier, van J.B.; Lettinga, G.

2008-01-01

Based on results of pilot scale research with source-separated black water (BW) and grey water (GW), a new sanitation concept is proposed. BW and GW are both treated in a UASB (-septic tank) for recovery of CH4 gas. Kitchen waste is added to the anaerobic BW treatment for doubling the biogas

Separation of mycotoxin-containing sources in grain dust and determination of their mycotoxin potential.

Science.gov (United States)

Palmgren, M S; Lee, L S

1986-01-01

Two distinct reservoirs of mycotoxins exist in fungal-infected cereal grains--the fungal spores and the spore-free mycelium-substrate matrix. Many fungal spores are of respirable size and the mycelium-substrate matrix can be pulverized to form particles of respirable size during routine handling of grain. In order to determine the contribution of each source to the level of mycotoxin contamination of dust, we developed techniques to harvest and separate mycelium-substrate matrices from spores of fungi. Conventional quantitative chromatographic analyses of separated materials indicated that aflatoxin from Aspergillus parasiticus, norsolorinic acid from a mutant of A. parasiticus, and secalonic acid D from Penicillium oxalicum were concentrated in the mycelium-substrate matrices and not in the spores. In contrast, spores of Aspergillus niger and Aspergillus fumigatus contained significant concentrations of aurasperone C and fumigaclavine C, respectively; only negligible amounts of the toxins were detected in the mycelium-substrate matrices of these two fungi. PMID:3709472

Laser separation of uranium isotopes

International Nuclear Information System (INIS)

Porter, J.T.

1981-01-01

Method and apparatus for separating uranium isotopes are claimed. The method comprises the steps of irradiating a uranyl source material at a wavelength selective to a desired isotope and at an effective temperature for isotope spectral line splitting below about 77 deg.K., further irradiating the source material within the fluorescent lifetime of the source material to selectively photochemically reduce the excited isotopic species, and chemically separating the reduced isotope species from the remaining uranyl salt compound

Separation of mouse testis cells on a Celsep (TM) apparatus and their usefulness as a source of high molecular weight DNA or RNA

Science.gov (United States)

Wolgemuth, D. J.; Gizang-Ginsberg, E.; Engelmyer, E.; Gavin, B. J.; Ponzetto, C.

1985-01-01

The use of a self-contained unit-gravity cell separation apparatus for separation of populations of mouse testicular cells is described. The apparatus, a Celsep (TM), maximizes the unit area over which sedimentation occurs, reduces the amount of separation medium employed, and is quite reproducible. Cells thus isolated have been good sources for isolation of DNA, and notably, high molecular weight RNA.

Sound field separation with cross measurement surfaces.

Directory of Open Access Journals (Sweden)

Jin Mao

Full Text Available With conventional near-field acoustical holography, it is impossible to identify sound pressure when the coherent sound sources are located on the same side of the array. This paper proposes a solution, using cross measurement surfaces to separate the sources based on the equivalent source method. Each equivalent source surface is built in the center of the corresponding original source with a spherical surface. According to the different transfer matrices between equivalent sources and points on holographic surfaces, the weighting of each equivalent source from coherent sources can be obtained. Numerical and experimental studies have been performed to test the method. For the sound pressure including noise after separation in the experiment, the calculation accuracy can be improved by reconstructing the pressure with Tikhonov regularization and the L-curve method. On the whole, a single source can be effectively separated from coherent sources using cross measurement.

A radiochemical separation of spallogenic 88Zr in the carrier-free state for radioisotopic photoneutron sources

International Nuclear Information System (INIS)

Whipple, R.E.; Grant, P.M.; Daniels, R.J.; Daniels, W.R.; O'Brien, H.A.Jr.

1976-01-01

As the precursor of its 88 Y daughter, 88 Zr could be advantageously included in the active component of the 88 Y-Be photoneutron source for several reasons. The spallation of Mo targets with medium-energy protons at LAMPF procedure has been developed to separate radiozirconium from the target material and various spallogenic impurities. 88 Zr can consequently be obtained carrier-free and in quantitative yield. (author)

Examination of some assumed severe reactor accidents at the Olkiluoto nuclear power plant

International Nuclear Information System (INIS)

Pekkarinen, E.; Rossi, J.

1989-02-01

Knowledge and analysis methods of severe accidents at nuclear power plants and of subsequent response of primary system and containment have been developed in last few years to the extent that realistic source tems of the specified accident sequences can be calculated for the Finnish nuclear power plants. The objective of this investigation was to calculate the source terms of off-site consequences brought about by some selected severe accident sequences initiated by the total loss of on-site and off-site AC power at the Olkiluoto nuclear power plant. The results describing the estimated off-site health risks are expressed as conditional assuming that the accident has taken place, because the probabilities of the occurence of the accident sequences considered have not been analysed in this study. The range and probabilities of occurence of health detriments are considered by calculating consequences in different weeather conditions and taking into account the annual frequency of each weather condition and statistical population distribution. The calculational results indicate that the reactor building provides and additional holdup and deposition of radioactive substance (except coble gases) released from the containment. Furthermore, the release fractions of the core inventory to the environment of volatile fission products such as iodine, cesium and tellurium remain under 0.03. No early health effects are predicted for the surrounding population in case the assumed short-tem countermeasures are performed effectively. Acute health effects are extremely improbable even without any active countermeasure. By reducing the long-term exposure from contaminated agricultural products, the collective dose from natural long-term background radiation, for instance in the sector of 30 degrees towards the southern Finland up to the distance of 300 kilometers, would be expected to increase with 2-20 percent depending on the release considered

Development of the high temperature ion-source for the Grenoble electromagnetic isotope separator; Etude et realisation de la source d'ions a haute temperature du separateur electromagnetique d'isotopes de Grenoble

Energy Technology Data Exchange (ETDEWEB)

Bouriant, M [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1967-12-01

The production of high purity stable or radioactive isotopes ({>=} 99.99 per cent) using electromagnetic separation require for equipment having a high resolving power. Besides, and in order to collect rare or short half-life isotopes, the efficiency of the ion-source must be high ({eta} > 5 to 10 per cent). With this in view, the source built operates at high temperatures (2500-3000 C) and makes use of ionisation by electronic bombardment or of thermo-ionisation. A summary is given in the first part of this work on the essential characteristics of the isotope separator ion Sources; a diagram of the principle of the source built is then given together with its characteristics. In the second part are given the values of the resolving power and of the efficiency of the Grenoble isotope separator fitted with such a source. The resolving power measured at 10 per cent of the peak height is of the order of 200. At the first magnetic stage the efficiency is between 1 and 26 per cent for a range of elements evaporating between 200 and 3000 C. Thus equipped, the separator has for example given, at the first stage, 10 mg of {sup 180}Hf at (99.69 {+-} 0.1) per cent corresponding to an enrichment coefficient of 580; recently 2 mg of {sup 150}Nd at (99.996 {+-} 0.002) per cent corresponding to an enrichment coefficient of 4.2 x 10{sup 5} has been obtained at the second stage. (author) [French] La production d'isotopes stables ou radioactifs de haute purete isotopique ({>=} 99.99 pour cent), par separation electromagnetique, exige des appareils de haut pouvoir de resolution. En outre, et en vue de collecter des isotopes de tres faible abondance ou de periode tres courte, le rendement des sources d'ions doit etre eleve ({eta} > 5 a 10 pour cent). Dans ce but, la source realisee fonctionne a haute temperature (2500-3000 C) et utilise l'ionisation par bombardement electronique, ou la thermoionisation. Dans la premiere partie de ce travail, on resume d'abord les caracteristiques

Noise-Source Separation Using Internal and Far-Field Sensors for a Full-Scale Turbofan Engine

Science.gov (United States)

Hultgren, Lennart S.; Miles, Jeffrey H.

2009-01-01

Noise-source separation techniques for the extraction of the sub-dominant combustion noise from the total noise signatures obtained in static-engine tests are described. Three methods are applied to data from a static, full-scale engine test. Both 1/3-octave and narrow-band results are discussed. The results are used to assess the combustion-noise prediction capability of the Aircraft Noise Prediction Program (ANOPP). A new additional phase-angle-based discriminator for the three-signal method is also introduced.

Hydrograph separation techniques in snowmelt-dominated watersheds

Science.gov (United States)

Miller, S.; Miller, S. N.

2017-12-01

This study integrates hydrological, geochemical, and isotopic data for a better understanding of different streamflow generation pathways and residence times in a snowmelt-dominated region. A nested watershed design with ten stream gauging sites recording sub-hourly stream stage has been deployed in a snowmelt-dominated region in southeastern Wyoming, heavily impacted by the recent bark beetle epidemic. LiDAR-derived digital elevation models help elucidate effects from topography and watershed metrics. At each stream gauging site, sub-hourly stream water conductivity and temperature data are also recorded. Hydrograph separation is a useful technique for determining different sources of runoff and how volumes from each source vary over time. Following previous methods, diurnal cycles from sub-hourly recorded streamflow and specific conductance data are analyzed and used to separate hydrographs into overland flow and baseflow components, respectively. A final component, vadose-zone flow, is assumed to be the remaining water from the total hydrograph. With access to snowmelt and precipitation data from nearby instruments, runoff coefficients are calculated for the different mechanisms, providing information on watershed response. Catchments are compared to understand how different watershed characteristics translate snowmelt or precipitation events into runoff. Portable autosamplers were deployed at two of the gauging sites for high-frequency analysis of stream water isotopic composition during peak flow to compare methods of hydrograph separation. Sampling rates of one or two hours can detect the diurnal streamflow cycle common during peak snowmelt. Prior research suggests the bark beetle epidemic has had little effect on annual streamflow patterns; however, several results show an earlier shift in the day of year in which peak annual streamflow is observed. The diurnal cycle is likely to comprise a larger percentage of daily streamflow during snowmelt in post

Saline sewage treatment and source separation of urine for more sustainable urban water management.

Science.gov (United States)

Ekama, G A; Wilsenach, J A; Chen, G H

2011-01-01

While energy consumption and its associated carbon emission should be minimized in wastewater treatment, it has a much lower priority than human and environmental health, which are both closely related to efficient water quality management. So conservation of surface water quality and quantity are more important for sustainable development than green house gas (GHG) emissions per se. In this paper, two urban water management strategies to conserve fresh water quality and quantity are considered: (1) source separation of urine for improved water quality and (2) saline (e.g. sea) water toilet flushing for reduced fresh water consumption in coastal and mining cities. The former holds promise for simpler and shorter sludge age activated sludge wastewater treatment plants (no nitrification and denitrification), nutrient (Mg, K, P) recovery and improved effluent quality (reduced endocrine disruptor and environmental oestrogen concentrations) and the latter for significantly reduced fresh water consumption, sludge production and oxygen demand (through using anaerobic bioprocesses) and hence energy consumption. Combining source separation of urine and saline water toilet flushing can reduce sewer crown corrosion and reduce effluent P concentrations. To realize the advantages of these two approaches will require significant urban water management changes in that both need dual (fresh and saline) water distribution and (yellow and grey/brown) wastewater collection systems. While considerable work is still required to evaluate these new approaches and quantify their advantages and disadvantages, it would appear that the investment for dual water distribution and wastewater collection systems may be worth making to unlock their benefits for more sustainable urban development.

A short study to assess the potential of independent component analysis for motion artifact separation in wearable pulse oximeter signals.

Science.gov (United States)

Yao, Jianchu; Warren, Steve

2005-01-01

Motion artifact reduction and separation become critical when medical sensors are used in wearable monitoring scenarios. Previous research has demonstrated that independent component analysis (ICA) can be applied to pulse oximeter signals to separate photoplethysmographic (PPG) data from motion artifacts, ambient light, and other interference in low-motion environments. However, ICA assumes that all source signal component pairs are mutually independent. It is important to assess the statistical independence of the source components in PPG data, especially if ICA is to be applied in ambulatory monitoring environments, where motion artifacts can have a substantial effect on the quality of data received from light-based sensors. This paper addresses the statistical relationship between motion artifacts and PPG data by calculating the correlation coefficients between arterial volume variations and motion over a range of stationary to high-motion conditions. Analyses indicate that motion significantly affects arterial flow, so care must be taken when applying ICA to light-based sensor data acquired from wearable platforms.

Modeling turbulent/chemistry interactions using assumed pdf methods

Science.gov (United States)

Gaffney, R. L, Jr.; White, J. A.; Girimaji, S. S.; Drummond, J. P.

1992-01-01

Two assumed probability density functions (pdfs) are employed for computing the effect of temperature fluctuations on chemical reaction. The pdfs assumed for this purpose are the Gaussian and the beta densities of the first kind. The pdfs are first used in a parametric study to determine the influence of temperature fluctuations on the mean reaction-rate coefficients. Results indicate that temperature fluctuations significantly affect the magnitude of the mean reaction-rate coefficients of some reactions depending on the mean temperature and the intensity of the fluctuations. The pdfs are then tested on a high-speed turbulent reacting mixing layer. Results clearly show a decrease in the ignition delay time due to increases in the magnitude of most of the mean reaction rate coefficients.

CO2 emission factors for waste incineration: Influence from source separation of recyclable materials

DEFF Research Database (Denmark)

Larsen, Anna Warberg; Astrup, Thomas

2011-01-01

variations between emission factors for different incinerators, but the background for these variations has not been thoroughly examined. One important reason may be variations in collection of recyclable materials as source separation alters the composition of the residual waste incinerated. The objective...... routed to incineration. Emission factors ranged from 27 to 40kg CO2/GJ. The results appeared most sensitive towards variations in waste composition and water content. Recycling rates and lower heating values could not be used as simple indicators of the resulting emission factors for residual household...... different studies and when using the values for environmental assessment purposes....

Light mesons and separated J(PC) sources in N-antiN annihilations at rest

International Nuclear Information System (INIS)

Lucaci-Timoce, Angela; Lazanu, I.

2002-01-01

N-antiN annihilations at rest and in flight are the most productive physics tools to investigate the spectroscopy of light mesons. The annihilations proceed from more sources of initial states, with different J (PC) quantum numbers. This makes the interpretation of the experimental data much more difficult than in the case of other annihilation process, as for example the e + e - annihilations, and introduces ambiguities in the results. In this talk, the possibilities to separate the N-antiN contributions of initial quantum states in different annihilation channels, are analyzed. The interference phenomena that appear are also discussed. (authors)

A Hybrid Technique for Blind Separation of Non-Gaussian and Time-Correlated Sources Using a Multicomponent Approach

Czech Academy of Sciences Publication Activity Database

Tichavský, Petr; Koldovský, Zbyněk; Yeredor, A.; Gómez-Herrero, G.; Doron, E.

2008-01-01

Roč. 19, č. 3 (2008), s. 421-430 ISSN 1045-9227 R&D Projects: GA MŠk 1M0572 Grant - others:GA ČR(CZ) GP102/07/P384 Program:GP Institutional research plan: CEZ:AV0Z10750506 Keywords : blind source separation * independent component analysis Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 3.726, year: 2008

Fate of personal care and household products in source separated sanitation.

Science.gov (United States)

Butkovskyi, A; Rijnaarts, H H M; Zeeman, G; Hernandez Leal, L

2016-12-15

Removal of twelve micropollutants, namely biocides, fragrances, ultraviolet (UV)-filters and preservatives in source separated grey and black water treatment systems was studied. All compounds were present in influent grey water in μg/l range. Seven compounds were found in influent black water. Their removal in an aerobic activated sludge system treating grey water ranged from 59% for avobenzone to >99% for hexylcinnamaldehyde. High concentrations of hydrophobic micropollutants in sludge of aerobic activated sludge system indicated the importance of sorption for their removal. Six micropollutants were found in sludge of an Up-flow anaerobic sludge blanket (UASB) reactor treating black water, with four of them being present at significantly higher concentrations after addition of grey water sludge to the reactor. Hence, addition of grey water sludge to the UASB reactor is likely to increase micropollutant content in UASB sludge. This approach should not be followed when excess UASB sludge is designed to be reused as soil amendment. Copyright © 2016 Elsevier B.V. All rights reserved.

Decentralized modal identification using sparse blind source separation

International Nuclear Information System (INIS)

Sadhu, A; Hazra, B; Narasimhan, S; Pandey, M D

2011-01-01

Popular ambient vibration-based system identification methods process information collected from a dense array of sensors centrally to yield the modal properties. In such methods, the need for a centralized processing unit capable of satisfying large memory and processing demands is unavoidable. With the advent of wireless smart sensor networks, it is now possible to process information locally at the sensor level, instead. The information at the individual sensor level can then be concatenated to obtain the global structure characteristics. A novel decentralized algorithm based on wavelet transforms to infer global structure mode information using measurements obtained using a small group of sensors at a time is proposed in this paper. The focus of the paper is on algorithmic development, while the actual hardware and software implementation is not pursued here. The problem of identification is cast within the framework of under-determined blind source separation invoking transformations of measurements to the time–frequency domain resulting in a sparse representation. The partial mode shape coefficients so identified are then combined to yield complete modal information. The transformations are undertaken using stationary wavelet packet transform (SWPT), yielding a sparse representation in the wavelet domain. Principal component analysis (PCA) is then performed on the resulting wavelet coefficients, yielding the partial mixing matrix coefficients from a few measurement channels at a time. This process is repeated using measurements obtained from multiple sensor groups, and the results so obtained from each group are concatenated to obtain the global modal characteristics of the structure

Decentralized modal identification using sparse blind source separation

Science.gov (United States)

Sadhu, A.; Hazra, B.; Narasimhan, S.; Pandey, M. D.

2011-12-01

Popular ambient vibration-based system identification methods process information collected from a dense array of sensors centrally to yield the modal properties. In such methods, the need for a centralized processing unit capable of satisfying large memory and processing demands is unavoidable. With the advent of wireless smart sensor networks, it is now possible to process information locally at the sensor level, instead. The information at the individual sensor level can then be concatenated to obtain the global structure characteristics. A novel decentralized algorithm based on wavelet transforms to infer global structure mode information using measurements obtained using a small group of sensors at a time is proposed in this paper. The focus of the paper is on algorithmic development, while the actual hardware and software implementation is not pursued here. The problem of identification is cast within the framework of under-determined blind source separation invoking transformations of measurements to the time-frequency domain resulting in a sparse representation. The partial mode shape coefficients so identified are then combined to yield complete modal information. The transformations are undertaken using stationary wavelet packet transform (SWPT), yielding a sparse representation in the wavelet domain. Principal component analysis (PCA) is then performed on the resulting wavelet coefficients, yielding the partial mixing matrix coefficients from a few measurement channels at a time. This process is repeated using measurements obtained from multiple sensor groups, and the results so obtained from each group are concatenated to obtain the global modal characteristics of the structure.

A new method for quantifying the performance of EEG blind source separation algorithms by referencing a simultaneously recorded ECoG signal.

Science.gov (United States)

Oosugi, Naoya; Kitajo, Keiichi; Hasegawa, Naomi; Nagasaka, Yasuo; Okanoya, Kazuo; Fujii, Naotaka

2017-09-01

Blind source separation (BSS) algorithms extract neural signals from electroencephalography (EEG) data. However, it is difficult to quantify source separation performance because there is no criterion to dissociate neural signals and noise in EEG signals. This study develops a method for evaluating BSS performance. The idea is neural signals in EEG can be estimated by comparison with simultaneously measured electrocorticography (ECoG). Because the ECoG electrodes cover the majority of the lateral cortical surface and should capture most of the original neural sources in the EEG signals. We measured real EEG and ECoG data and developed an algorithm for evaluating BSS performance. First, EEG signals are separated into EEG components using the BSS algorithm. Second, the EEG components are ranked using the correlation coefficients of the ECoG regression and the components are grouped into subsets based on their ranks. Third, canonical correlation analysis estimates how much information is shared between the subsets of the EEG components and the ECoG signals. We used our algorithm to compare the performance of BSS algorithms (PCA, AMUSE, SOBI, JADE, fastICA) via the EEG and ECoG data of anesthetized nonhuman primates. The results (Best case >JADE = fastICA >AMUSE = SOBI ≥ PCA >random separation) were common to the two subjects. To encourage the further development of better BSS algorithms, our EEG and ECoG data are available on our Web site (http://neurotycho.org/) as a common testing platform. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Gradient Flow Convolutive Blind Source Separation

DEFF Research Database (Denmark)

Pedersen, Michael Syskind; Nielsen, Chinton Møller

2004-01-01

Experiments have shown that the performance of instantaneous gradient flow beamforming by Cauwenberghs et al. is reduced significantly in reverberant conditions. By expanding the gradient flow principle to convolutive mixtures, separation in a reverberant environment is possible. By use...... of a circular four microphone array with a radius of 5 mm, and applying convolutive gradient flow instead of just applying instantaneous gradient flow, experimental results show an improvement of up to around 14 dB can be achieved for simulated impulse responses and up to around 10 dB for a hearing aid...

PSFGAN: a generative adversarial network system for separating quasar point sources and host galaxy light

Science.gov (United States)

Stark, Dominic; Launet, Barthelemy; Schawinski, Kevin; Zhang, Ce; Koss, Michael; Turp, M. Dennis; Sartori, Lia F.; Zhang, Hantian; Chen, Yiru; Weigel, Anna K.

2018-06-01

The study of unobscured active galactic nuclei (AGN) and quasars depends on the reliable decomposition of the light from the AGN point source and the extended host galaxy light. The problem is typically approached using parametric fitting routines using separate models for the host galaxy and the point spread function (PSF). We present a new approach using a Generative Adversarial Network (GAN) trained on galaxy images. We test the method using Sloan Digital Sky Survey r-band images with artificial AGN point sources added that are then removed using the GAN and with parametric methods using GALFIT. When the AGN point source is more than twice as bright as the host galaxy, we find that our method, PSFGAN, can recover point source and host galaxy magnitudes with smaller systematic error and a lower average scatter (49 per cent). PSFGAN is more tolerant to poor knowledge of the PSF than parametric methods. Our tests show that PSFGAN is robust against a broadening in the PSF width of ± 50 per cent if it is trained on multiple PSFs. We demonstrate that while a matched training set does improve performance, we can still subtract point sources using a PSFGAN trained on non-astronomical images. While initial training is computationally expensive, evaluating PSFGAN on data is more than 40 times faster than GALFIT fitting two components. Finally, PSFGAN is more robust and easy to use than parametric methods as it requires no input parameters.

39 CFR 3060.40 - Calculation of the assumed Federal income tax.

Science.gov (United States)

2010-07-01

... Federal income tax. (a) The assumed Federal income tax on competitive products income shall be based on the Postal Service theoretical competitive products enterprise income statement for the relevant year... 39 Postal Service 1 2010-07-01 2010-07-01 false Calculation of the assumed Federal income tax...

A simple alkali-metal and noble gas ion source for SIMS equipments with mass separation of the primary ions

International Nuclear Information System (INIS)

Duesterhoeft, H.; Pippig, R.

1986-01-01

An alkali-metal ion source working without a store of alkali-metals is described. The alkali-metal ions are produced by evaporation of alkali salts and ionization in a low-voltage arc discharge stabilized with a noble gas plasma or in the case of small alkali-metal ion currents on the base of the well known thermic ionization at a hot tungsten wire. The source is very simple in construction and produces a stable ion current of 0.3 μA for more than 100 h. It is possible to change the ion species in a short time. This source is applicable to all SIMS equipments using mass separation for primary ions. (author)

Development of an Ionization Scheme for Gold using the Selective Laser Ion Source at the On-Line Isotope Separator ISOLDE

CERN Document Server

Fedosseev, V; Marsh, B A; CERN. Geneva. AB Department

2006-01-01

At the ISOLDE on-line isotope separation facility, the resonance ionization laser ion source (RILIS) can be used to ionize reaction products as they effuse from the target. The RILIS process of laser step-wise resonance ionization of atoms in a hot metal cavity provides a highly element selective stage in the preparation of the radioactive ion beam. As a result, the ISOLDE mass separators can provide beams of a chosen isotope with greatly reduced isobaric contamination. The number of elements available at RILIS has been extended to 26, with the addition of a new three-step ionization scheme for gold. The optimal ionization scheme was determined during an extensive study of the atomic energy levels and auto-ionizing states of gold, carried out by means of in-source resonance ionization spectroscopy. Details of the ionization scheme and a summary of the spectroscopy study are presented.

Synthesis of blind source separation algorithms on reconfigurable FPGA platforms

Science.gov (United States)

Du, Hongtao; Qi, Hairong; Szu, Harold H.

2005-03-01

Recent advances in intelligence technology have boosted the development of micro- Unmanned Air Vehicles (UAVs) including Sliver Fox, Shadow, and Scan Eagle for various surveillance and reconnaissance applications. These affordable and reusable devices have to fit a series of size, weight, and power constraints. Cameras used on such micro-UAVs are therefore mounted directly at a fixed angle without any motion-compensated gimbals. This mounting scheme has resulted in the so-called jitter effect in which jitter is defined as sub-pixel or small amplitude vibrations. The jitter blur caused by the jitter effect needs to be corrected before any other processing algorithms can be practically applied. Jitter restoration has been solved by various optimization techniques, including Wiener approximation, maximum a-posteriori probability (MAP), etc. However, these algorithms normally assume a spatial-invariant blur model that is not the case with jitter blur. Szu et al. developed a smart real-time algorithm based on auto-regression (AR) with its natural generalization of unsupervised artificial neural network (ANN) learning to achieve restoration accuracy at the sub-pixel level. This algorithm resembles the capability of the human visual system, in which an agreement between the pair of eyes indicates "signal", otherwise, the jitter noise. Using this non-statistical method, for each single pixel, a deterministic blind sources separation (BSS) process can then be carried out independently based on a deterministic minimum of the Helmholtz free energy with a generalization of Shannon's information theory applied to open dynamic systems. From a hardware implementation point of view, the process of jitter restoration of an image using Szu's algorithm can be optimized by pixel-based parallelization. In our previous work, a parallelly structured independent component analysis (ICA) algorithm has been implemented on both Field Programmable Gate Array (FPGA) and Application

A Novel Partial Discharge Ultra-High Frequency Signal De-Noising Method Based on a Single-Channel Blind Source Separation Algorithm

Directory of Open Access Journals (Sweden)

Liangliang Wei

2018-02-01

Full Text Available To effectively de-noise the Gaussian white noise and periodic narrow-band interference in the background noise of partial discharge ultra-high frequency (PD UHF signals in field tests, a novel de-noising method, based on a single-channel blind source separation algorithm, is proposed. Compared with traditional methods, the proposed method can effectively de-noise the noise interference, and the distortion of the de-noising PD signal is smaller. Firstly, the PD UHF signal is time-frequency analyzed by S-transform to obtain the number of source signals. Then, the single-channel detected PD signal is converted into multi-channel signals by singular value decomposition (SVD, and background noise is separated from multi-channel PD UHF signals by the joint approximate diagonalization of eigen-matrix method. At last, the source PD signal is estimated and recovered by the l1-norm minimization method. The proposed de-noising method was applied on the simulation test and field test detected signals, and the de-noising performance of the different methods was compared. The simulation and field test results demonstrate the effectiveness and correctness of the proposed method.

Modal parameter identification based on combining transmissibility functions and blind source separation techniques

Science.gov (United States)

Araújo, Iván Gómez; Sánchez, Jesús Antonio García; Andersen, Palle

2018-05-01

Transmissibility-based operational modal analysis is a recent and alternative approach used to identify the modal parameters of structures under operational conditions. This approach is advantageous compared with traditional operational modal analysis because it does not make any assumptions about the excitation spectrum (i.e., white noise with a flat spectrum). However, common methodologies do not include a procedure to extract closely spaced modes with low signal-to-noise ratios. This issue is relevant when considering that engineering structures generally have closely spaced modes and that their measured responses present high levels of noise. Therefore, to overcome these problems, a new combined method for modal parameter identification is proposed in this work. The proposed method combines blind source separation (BSS) techniques and transmissibility-based methods. Here, BSS techniques were used to recover source signals, and transmissibility-based methods were applied to estimate modal information from the recovered source signals. To achieve this combination, a new method to define a transmissibility function was proposed. The suggested transmissibility function is based on the relationship between the power spectral density (PSD) of mixed signals and the PSD of signals from a single source. The numerical responses of a truss structure with high levels of added noise and very closely spaced modes were processed using the proposed combined method to evaluate its ability to identify modal parameters in these conditions. Colored and white noise excitations were used for the numerical example. The proposed combined method was also used to evaluate the modal parameters of an experimental test on a structure containing closely spaced modes. The results showed that the proposed combined method is capable of identifying very closely spaced modes in the presence of noise and, thus, may be potentially applied to improve the identification of damping ratios.

Streaming effect of wall oscillation to boundary layer separation

Science.gov (United States)

Wu, X. H.; Wu, J. Z.; Wu, J. M.

1991-01-01

This paper presents a preliminary theoretical result on the time averaged streaming effect of local forcing excitation to the boundary layer separation from smooth surface. The problem is formulated as a periodic disturbance to a basic steady breakaway separating flow, for which the data are taken from a numerical triple-deck solution. The ratio of Strouhal number St and Reynolds number Re plays an important role, both being assumed sufficiently high. The analytical and numerical results show that this streaming effect is quite strong at proper values of St/Re exp 1/4, which may delay or even suppress the separation.

A review of output-only structural mode identification literature employing blind source separation methods

Science.gov (United States)

Sadhu, A.; Narasimhan, S.; Antoni, J.

2017-09-01

Output-only modal identification has seen significant activity in recent years, especially in large-scale structures where controlled input force generation is often difficult to achieve. This has led to the development of new system identification methods which do not require controlled input. They often work satisfactorily if they satisfy some general assumptions - not overly restrictive - regarding the stochasticity of the input. Hundreds of papers covering a wide range of applications appear every year related to the extraction of modal properties from output measurement data in more than two dozen mechanical, aerospace and civil engineering journals. In little more than a decade, concepts of blind source separation (BSS) from the field of acoustic signal processing have been adopted by several researchers and shown that they can be attractive tools to undertake output-only modal identification. Originally intended to separate distinct audio sources from a mixture of recordings, mathematical equivalence to problems in linear structural dynamics have since been firmly established. This has enabled many of the developments in the field of BSS to be modified and applied to output-only modal identification problems. This paper reviews over hundred articles related to the application of BSS and their variants to output-only modal identification. The main contribution of the paper is to present a literature review of the papers which have appeared on the subject. While a brief treatment of the basic ideas are presented where relevant, a comprehensive and critical explanation of their contents is not attempted. Specific issues related to output-only modal identification and the relative advantages and limitations of BSS methods both from theoretical and application standpoints are discussed. Gap areas requiring additional work are also summarized and the paper concludes with possible future trends in this area.

Bowing-reactivity trends in EBR-II assuming zero-swelling ducts

International Nuclear Information System (INIS)

Meneghetti, D.

1994-01-01

Predicted trends of duct-bowing reactivities for the Experimental Breeder Reactor II (EBR-II) are correlated with predicted row-wise duct deflections assuming use of idealized zero-void-swelling subassembly ducts. These assume no irradiation induced swellings of ducts but include estimates of the effects of irradiation-creep relaxation of thermally induced bowing stresses. The results illustrate the manners in which at-power creeps may affect subsequent duct deflections at zero power and thereby the trends of the bowing component of a subsequent power reactivity decrement

Assuming a Pharmacy Organization Leadership Position: A Guide for Pharmacy Leaders.

Science.gov (United States)

Shay, Blake; Weber, Robert J

2015-11-01

Important and influential pharmacy organization leadership positions, such as president, board member, or committee chair, are volunteer positions and require a commitment of personal and professional time. These positions provide excellent opportunities for leadership development, personal promotion, and advancement of the profession. In deciding to assume a leadership position, interested individuals must consider the impact on their personal and professional commitments and relationships, career planning, employer support, current and future department projects, employee support, and personal readiness. This article reviews these factors and also provides an assessment tool that leaders can use to determine their readiness to assume leadership positions. By using an assessment tool, pharmacy leaders can better understand their ability to assume an important and influential leadership position while achieving job and personal goals.

Fast Monaural Separation of Speech

DEFF Research Database (Denmark)

Pontoppidan, Niels Henrik; Dyrholm, Mads

2003-01-01

a Factorial Hidden Markov Model, with non-stationary assumptions on the source autocorrelations modelled through the Factorial Hidden Markov Model, leads to separation in the monaural case. By extending Hansens work we find that Roweis' assumptions are necessary for monaural speech separation. Furthermore we...

PSFGAN: a generative adversarial network system for separating quasar point sources and host galaxy light

Science.gov (United States)

Stark, Dominic; Launet, Barthelemy; Schawinski, Kevin; Zhang, Ce; Koss, Michael; Turp, M. Dennis; Sartori, Lia F.; Zhang, Hantian; Chen, Yiru; Weigel, Anna K.

2018-03-01

The study of unobscured active galactic nuclei (AGN) and quasars depends on the reliable decomposition of the light from the AGN point source and the extended host galaxy light. The problem is typically approached using parametric fitting routines using separate models for the host galaxy and the point spread function (PSF). We present a new approach using a Generative Adversarial Network (GAN) trained on galaxy images. We test the method using Sloan Digital Sky Survey (SDSS) r-band images with artificial AGN point sources added which are then removed using the GAN and with parametric methods using GALFIT. When the AGN point source PS is more than twice as bright as the host galaxy, we find that our method, PSFGAN, can recover PS and host galaxy magnitudes with smaller systematic error and a lower average scatter (49%). PSFGAN is more tolerant to poor knowledge of the PSF than parametric methods. Our tests show that PSFGAN is robust against a broadening in the PSF width of ±50% if it is trained on multiple PSF's. We demonstrate that while a matched training set does improve performance, we can still subtract point sources using a PSFGAN trained on non-astronomical images. While initial training is computationally expensive, evaluating PSFGAN on data is more than 40 times faster than GALFIT fitting two components. Finally, PSFGAN it is more robust and easy to use than parametric methods as it requires no input parameters.

Localization and separation of acoustic sources by using a 2.5-dimensional circular microphone array.

Science.gov (United States)

Bai, Mingsian R; Lai, Chang-Sheng; Wu, Po-Chen

2017-07-01

Circular microphone arrays (CMAs) are sufficient in many immersive audio applications because azimuthal angles of sources are considered more important than the elevation angles in those occasions. However, the fact that CMAs do not resolve the elevation angle well can be a limitation for some applications which involves three-dimensional sound images. This paper proposes a 2.5-dimensional (2.5-D) CMA comprised of a CMA and a vertical logarithmic-spacing linear array (LLA) on the top. In the localization stage, two delay-and-sum beamformers are applied to the CMA and the LLA, respectively. The direction of arrival (DOA) is estimated from the product of two array output signals. In the separation stage, Tikhonov regularization and convex optimization are employed to extract the source amplitudes on the basis of the estimated DOA. The extracted signals from two arrays are further processed by the normalized least-mean-square algorithm with the internal iteration to yield the source signal with improved quality. To validate the 2.5-D CMA experimentally, a three-dimensionally printed circular array comprised of a 24-element CMA and an eight-element LLA is constructed. Objective perceptual evaluation of speech quality test and a subjective listening test are also undertaken.

Household food waste separation behavior and the importance of convenience.

Science.gov (United States)

Bernstad, Anna

2014-07-01

Two different strategies aiming at increasing household source-separation of food waste were assessed through a case-study in a Swedish residential area (a) use of written information, distributed as leaflets amongst households and (b) installation of equipment for source-segregation of waste with the aim of increasing convenience food waste sorting in kitchens. Weightings of separately collected food waste before and after distribution of written information suggest that this resulted in neither a significant increased amount of separately collected food waste, nor an increased source-separation ratio. After installation of sorting equipment in households, both the amount of separately collected food waste as well as the source-separation ratio increased vastly. Long-term monitoring shows that results where longstanding. Results emphasize the importance of convenience and existence of infrastructure necessary for source-segregation of waste as important factors for household waste recycling, but also highlight the need of addressing these aspects where waste is generated, i.e. already inside the household. Copyright © 2014 Elsevier Ltd. All rights reserved.

Improved Tensor-Based Singular Spectrum Analysis Based on Single Channel Blind Source Separation Algorithm and Its Application to Fault Diagnosis

Directory of Open Access Journals (Sweden)

Dan Yang

2017-04-01

Full Text Available To solve the problem of multi-fault blind source separation (BSS in the case that the observed signals are under-determined, a novel approach for single channel blind source separation (SCBSS based on the improved tensor-based singular spectrum analysis (TSSA is proposed. As the most natural representation of high-dimensional data, tensor can preserve the intrinsic structure of the data to the maximum extent. Thus, TSSA method can be employed to extract the multi-fault features from the measured single-channel vibration signal. However, SCBSS based on TSSA still has some limitations, mainly including unsatisfactory convergence of TSSA in many cases and the number of source signals is hard to accurately estimate. Therefore, the improved TSSA algorithm based on canonical decomposition and parallel factors (CANDECOMP/PARAFAC weighted optimization, namely CP-WOPT, is proposed in this paper. CP-WOPT algorithm is applied to process the factor matrix using a first-order optimization approach instead of the original least square method in TSSA, so as to improve the convergence of this algorithm. In order to accurately estimate the number of the source signals in BSS, EMD-SVD-BIC (empirical mode decomposition—singular value decomposition—Bayesian information criterion method, instead of the SVD in the conventional TSSA, is introduced. To validate the proposed method, we applied it to the analysis of the numerical simulation signal and the multi-fault rolling bearing signals.

How Afghanistan Can Assume Ownership for the Ongoing Conflict

National Research Council Canada - National Science Library

Horn, Sr, John M

2008-01-01

In view of United States global commitments and larger Global War on Terror (GWOT) strategy, the ultimate security goal in Afghanistan must be for the Afghans to assume ownership of the counterinsurgency struggle...

Radiochemical determination and separation or total radium, 226Ra and 224Ra

International Nuclear Information System (INIS)

Suarez, J. A.; Gonzalez, J. A.; Pablo, M. A. de

1987-01-01

Radiochemical purification and separation of radium has been carried out and the determination of total radium solubilized in aqueous samples has been studied assuming that all the alpha emitters of the sample have their origin in the 226Ra and elements of its desintegration chain. Also, the activities of 22Ra and 226 Ra have been evaluated separately doing a measurement after the chemical separation of the radium and another one 10 days after. (Author) 9 refs

Multipoint investigation of the source region of storm-time chorus

Directory of Open Access Journals (Sweden)

O. Santolík

2004-07-01

Full Text Available In this case study we investigate the source region of whistler-mode chorus located close to the geomagnetic equator at a radial distance of 4.4 Earth radii. We use measurements from the four Cluster spacecraft at separations of less than a few hundreds of km, recorded during the geomagnetic storm of 18 April 2002. The waveforms of the electric field fluctuations were obtained by the WBD instruments in the frequency range 50Hz-9.5kHz. Using these data, we calculate linear and rank correlation coefficients of the frequency averaged power-spectral density measured by the different spacecraft. Those coefficients have been recently shown to decrease with spacecraft separation distance perpendicular to the static magnetic field cchor03 with a characteristic scale length of 100km. We find this characteristic scale varying between 60 and 200km for different data intervals inside the source region. We examine possible explanations for the observed large scatter of the correlation coefficients, and we suggest a simultaneously acting effect of random positions of locations at which the individual chorus wave packets are generated. The statistical properties of the observations are approximately reproduced by a simple 2-D model of the source region, assuming a perpendicular half-width of 35km (approximately one wavelength of the whistler-mode waves for the distribution of power radiated from individual active areas.

Modeling of the charge-state separation at ITEP experimental facility for material science based on a Bernas ion source.

Science.gov (United States)

Barminova, H Y; Saratovskyh, M S

2016-02-01

The experiment automation system is supposed to be developed for experimental facility for material science at ITEP, based on a Bernas ion source. The program CAMFT is assumed to be involved into the program of the experiment automation. CAMFT is developed to simulate the intense charged particle bunch motion in the external magnetic fields with arbitrary geometry by means of the accurate solution of the particle motion equation. Program allows the consideration of the bunch intensity up to 10(10) ppb. Preliminary calculations are performed at ITEP supercomputer. The results of the simulation of the beam pre-acceleration and following turn in magnetic field are presented for different initial conditions.

Separation of source and propagation effects at regional distances

Energy Technology Data Exchange (ETDEWEB)

Goldstein, P.; Jarpe, S.; Mayeda, K. [Lawrence Livermore National Lab., CA (United States)] [and others

1994-12-31

Improved estimates of the contributions of source and propagation effects to regional seismic signals are needed to explain the performance of existing discriminants and to help develop more robust methods for identifying underground explosions. In this paper, we use close-in, local, and regional estimates of explosion source time functions to remove source effects from regional recordings of the Non-Proliferation Experiment (NPE), a one kiloton chemical explosion in N-tunnel at Rainier Mesa on the Nevada Test Site, and nearby nuclear explosions and earthquakes. Using source corrected regional waveforms, we find that regional Pg and Lg spectra of shallow explosions have significant low frequency ({approximately}1Hz) enhancements when compared to normal depth earthquakes. Data and simulations suggest that such enhancements are most sensitive to source depth, but may also be a function of mechanism, source receiver distance, and regional structure.

Heavy Water - Industrial Separation Processes

International Nuclear Information System (INIS)

Peculea, M.

1984-01-01

This monograph devoted to the heavy water production mainly presents the Romanian experience in the field which started in early sixties from the laboratory scale production and reached now the level of large scale industrial production at ROMAG-Drobeta, Romania. The book is structured in eleven chapters entitled: Overview, The main physical properties, Sources, Uses, Separation factor and equilibrium constant, Mathematical modelling of the separation process, Thermodynamical considerations on the isotope separation, Selection criteria for heavy water separation processes, Industrial installations for heavy water production, Prospects, Acknowledgements. 200 Figs., 90 Tabs., 135 Refs

Separation by electrostatic equipments; Separacion por medios electrostaticos

Energy Technology Data Exchange (ETDEWEB)

Miguel, R.; Larrauri, E.; Arnaiz, S.; Cacho, S.; Robertson, C.; Smallwood, J.; Coilt, J.; Ufer, R.; Kohnlecher, R.

2000-07-01

Development of automated separation technologies is essential in increasing recovery rates, particularly from highly mixed sources such municipal solid wastes and wastes from electric and electronic equipment, and in reducing recycling costs. This frame moved GAIKER Technological Centre to look for new technologies that allow to recover materials such metals, plastics, papers from those waste sources. Electrostatic separation technology has been successfully applied to separate these materials collaborating to get the targets specified by legislation. (Author)

Source Separation of Heartbeat Sounds for Effective E-Auscultation

Science.gov (United States)

Geethu, R. S.; Krishnakumar, M.; Pramod, K. V.; George, Sudhish N.

2016-03-01

This paper proposes a cost effective solution for improving the effectiveness of e-auscultation. Auscultation is the most difficult skill for a doctor, since it can be acquired only through experience. The heart sound mixtures are captured by placing the four numbers of sensors at appropriate auscultation area in the body. These sound mixtures are separated to its relevant components by a statistical method independent component analysis. The separated heartbeat sounds can be further processed or can be stored for future reference. This idea can be used for making a low cost, easy to use portable instrument which will be beneficial to people living in remote areas and are unable to take the advantage of advanced diagnosis methods.

49 CFR 568.7 - Requirements for manufacturers who assume legal responsibility for a vehicle.

Science.gov (United States)

2010-10-01

... MANUFACTURED IN TWO OR MORE STAGES § 568.7 Requirements for manufacturers who assume legal responsibility for a vehicle. (a) If an incomplete vehicle manufacturer assumes legal responsibility for all duties and... 49 CFR 567.5(f). (b) If an intermediate manufacturer of a vehicle assumes legal responsibility for...

Separation of Electric Fields Into Potential and Inductive Parts, and Implications for Radial Diffusion

Science.gov (United States)

Chan, A. A.; Ilie, R.; Elkington, S. R.; Albert, J.; Huie, W.

2017-12-01

It has been traditional to separate radiation belt radial-diffusion coefficients into two contributions: an "electrostatic" diffusion coefficient, which is assumed to be due to a potential (non-inductive) electric field, and an "electromagnetic" diffusion coefficient , which is assumed to be due to the combined effect of an inductive electric field and the corresponding time-dependent magnetic field. One difficulty in implementing this separation when using magnetospheric fields obtained from measurements, or from MHD simulations, is that only the total electric field is given; the separation of the electric field into potential and inductive parts is not readily available. In this work we separate the electric field using a numerical method based on the Helmholtz decomposition of the total motional electric field calculated by the BATS-R-US MHD code. The inner boundary for the electric potential is based on the Ridley Ionospheric Model solution and we assume floating boundary conditions in the solar wind. Using different idealized solar wind drivers, including a solar wind density that is oscillating at a single frequency or with a broad spectrum of frequencies, we calculate potential and inductive electric fields, electric and magnetic power spectral densities, and corresponding radial diffusion coefficients. Simulations driven by idealized solar wind conditions show a clear separation of the potential and inductive contributions to the power spectral densities and diffusion coefficients. Simulations with more realistic solar wind drivers are underway to better assess the use of electrostatic and electromagnetic diffusion coefficients in understanding ULF wave-particle interactions in Earth's radiation belts.

Design of Smart Ion-Selective Electrode Arrays Based on Source Separation through Nonlinear Independent Component Analysis

Directory of Open Access Journals (Sweden)

Duarte L.T.

2014-03-01

Full Text Available The development of chemical sensor arrays based on Blind Source Separation (BSS provides a promising solution to overcome the interference problem associated with Ion-Selective Electrodes (ISE. The main motivation behind this new approach is to ease the time-demanding calibration stage. While the first works on this problem only considered the case in which the ions under analysis have equal valences, the present work aims at developing a BSS technique that works when the ions have different charges. In this situation, the resulting mixing model belongs to a particular class of nonlinear systems that have never been studied in the BSS literature. In order to tackle this sort of mixing process, we adopted a recurrent network as separating system. Moreover, concerning the BSS learning strategy, we develop a mutual information minimization approach based on the notion of the differential of the mutual information. The method works requires a batch operation, and, thus, can be used to perform off-line analysis. The validity of our approach is supported by experiments where the mixing model parameters were extracted from actual data.

A mathematical model for source separation of MMG signals recorded with a coupled microphone-accelerometer sensor pair.

Science.gov (United States)

Silva, Jorge; Chau, Tom

2005-09-01

Recent advances in sensor technology for muscle activity monitoring have resulted in the development of a coupled microphone-accelerometer sensor pair for physiological acousti signal recording. This sensor can be used to eliminate interfering sources in practical settings where the contamination of an acoustic signal by ambient noise confounds detection but cannot be easily removed [e.g., mechanomyography (MMG), swallowing sounds, respiration, and heart sounds]. This paper presents a mathematical model for the coupled microphone-accelerometer vibration sensor pair, specifically applied to muscle activity monitoring (i.e., MMG) and noise discrimination in externally powered prostheses for below-elbow amputees. While the model provides a simple and reliable source separation technique for MMG signals, it can also be easily adapted to other aplications where the recording of low-frequency (< 1 kHz) physiological vibration signals is required.

Blind speech separation system for humanoid robot with FastICA for audio filtering and separation

Science.gov (United States)

Budiharto, Widodo; Santoso Gunawan, Alexander Agung

2016-07-01

Nowadays, there are many developments in building intelligent humanoid robot, mainly in order to handle voice and image. In this research, we propose blind speech separation system using FastICA for audio filtering and separation that can be used in education or entertainment. Our main problem is to separate the multi speech sources and also to filter irrelevant noises. After speech separation step, the results will be integrated with our previous speech and face recognition system which is based on Bioloid GP robot and Raspberry Pi 2 as controller. The experimental results show the accuracy of our blind speech separation system is about 88% in command and query recognition cases.

Stable isotopic indicators of nitrous oxide and methane sources in Los Angeles, California

Science.gov (United States)

Townsend-Small, A.; Pataki, D.; Tyler, S.; Trumbore, S.

2008-12-01

As urbanization increasingly encroaches upon agricultural landscapes, there are greater potential sources of greenhouse gases and other atmospheric contaminants. Measurements of the isotopic composition of trace gases have the potential to distinguish between pollutant sources and quantify the proportional contribution of agricultural activities to the total atmospheric pool. In this study, we are measuring the isotopic composition of greenhouse gases N2O and CH4 emitted from cropland, animal feeding operations, and urban activities in the South Coast Air Basin in southern California. The ultimate goal of our project is to utilize atmospheric measurements of the isotopic composition of N2O and CH4 combined with studies of source signatures to determine the proportional contributions of cropland, animal operations, and urban sources of greenhouse gases to the atmosphere. Measurements of the δ13C of methane show excellent separation between urban sources, such as vehicle emissions, power plants, oil refineries, landfills, and sewage treatment plants and agricultural sources like cows, biogas, and cattle feedlots. For nitrous oxide, soil N2O sources showed good separation from wastewater treatment facilities using δ15N and δ18O. Within soil N2O sources, the isotopic composition of N2O from cropland soils was similar to N2O emissions from urban turfgrass. These data indicate that nitrification may be as important a source of N2O as denitrification in urban soils. We are also measuring N2O fluxes from soils and from sewage treatment processes, and preliminary data indicate that urban N2O fluxes are higher than initially assumed by managers and regulatory agencies.

Cascadia Subduction Zone Earthquake Source Spectra from an Array of Arrays

Science.gov (United States)

Gomberg, J. S.; Vidale, J. E.

2011-12-01

It is generally accepted that spectral characteristics distinguish 'slow' seismic sources from those of 'ordinary' or 'fast' earthquakes. To explore this difference, we measure ordinary earthquake spectra of about 30 seismic events located near the Cascadia plate interface where ETS regularly occurs. We separate the affects of local site response, regional propagation (attenuation and spreading), and processes near or at the source for a dense dataset recorded on an array of eight seismic micro-arrays. The arrays have apertures of 1-2 km with 21-31 seismographs in each, and are separated by 10-20 km. We assume that the spectrum of each recorded signal may be described by the product of 1) frequency-dependent site response, 2) propagation effects that include geometric spreading and an exponential decay that varies with distance, frequency, and 3) a frequency-dependent source spectrum. Using more than1000 seismograms from all events recorded at all sites simultaneously, we solve for frequency-dependent site response and source spectra, as well as a single regional Q value. We interpret only the slope of the source terms because most earthquakes have magnitudes less than 0, so we expect that their corner frequencies are higher frequency than the recorded passband. The amplitude variation in the site response within the same array sometimes exceeds a factor of 3, which is consistent with the variation seen visually. We see variability in the slopes of the source spectra comparable to the difference between 'slow' and 'fast' events observed in other studies, and which show a strong correlation with source location. Spectral slopes of spatially clustered sources are nearly identical but usually differ from those of clusters at a distance of a few tens of km, and spectral content varies systematically with location within the distribution of events. While these differences may reflect varying source processes (e.g., rupture velocity, stress drop), the strong correlation

Electromagnetic Separator of a Plasma

International Nuclear Information System (INIS)

Gasilin, Vladimir V.; Nezovibat'ko, Yuriy N.; Poklipach, Grigoriy S.; Shvets, Oleg M.; Taran, Valeriy S.; Tereshin, Vladimir I.

2006-01-01

Simple freestanding 90 deg. filter is used for obtaining the metallic vacuum coatings. As the source of metallic plasma adapted standard cathode vaporizer on the installation ''Bulat 6''. Plasma flow from the cathode flowed through the not protected by isolation spiral (solenoid). The solenoid outlet from the side of cathode find under the floating potential. The second solenoid outlet was connected to the autonomous power supply. Solenoid was prepared with the wide interval of the coil winding and with the turning to 90 degrees. Therefore, drifting charged of particle can freely depart from the interior of solenoid outside. The glow of the turned flow of plasma is observed during the supplying to the cathode and the solenoid. Flow is separation from the coils and is extended along the axis of solenoid. In this case over the solenoid flow the current 20-90 A, the voltage of solenoid relative to vessel (earth) + 15 V. We assume, that this device ensures radial electric field relative to the basic nucleus of the plasma (diameter of the nucleus of plasma column it is commensurate with the diameter of cathode) and the current of solenoid creates the longitudinal magnetic field (estimated order 20 oersted). Magnetic field strength is sufficient for the magnetization of electrons, but it is very small for the ions and the charged microdroplets. The carried out experiments on the application of coatings on the dielectric substrate with the use of aluminum and titanium cathodes showed the effectiveness of the work of this separator. Coatings without the drops are obtained also on the glass substrate with HF- displacement. The reflective properties of the metallic films (Ti,Al) on the glass samples were measured

Emissions of Volatile Organic Compounds (VOCs) from Animal Husbandry: Chemical Compositions, Separation of Sources and Animal Types

Science.gov (United States)

Yuan, B.; Coggon, M.; Koss, A.; Warneke, C.; Eilerman, S. J.; Neuman, J. A.; Peischl, J.; Aikin, K. C.; Ryerson, T. B.; De Gouw, J. A.

2016-12-01

Concentrated animal feeding operations (CAFOs) are important sources of volatile organic compounds (VOCs) in the atmosphere. We used a hydronium ion time-of-flight chemical ionization mass spectrometer (H3O+ ToF-CIMS) to measure VOC emissions from CAFOs in the Northern Front Range of Colorado during an aircraft campaign (SONGNEX) for regional contributions and from a mobile laboratory sampling for chemical characterizations of individual animal feedlots. The main VOCs emitted from CAFOs include carboxylic acids, alcohols, carbonyls, phenolic species, sulfur- and nitrogen-containing species. Alcohols and carboxylic acids dominate VOC concentrations. Sulfur-containing and phenolic species become more important in terms of odor activity values and NO3 reactivity, respectively. The high time-resolution mobile measurements allow the separation of the sources of VOCs from different parts of the operations occurring within the facilities. We show that the increase of ethanol concentrations were primarily associated with feed storage and handling. We apply a multivariate regression analysis using NH3 and ethanol as tracers to attribute the relative importance of animal-related emissions (animal exhalation and waste) and feed-related emissions (feed storage and handling) for different VOC species. Feed storage and handling contribute significantly to emissions of alcohols, carbonyls and carboxylic acids. Phenolic species and nitrogen-containing species are predominantly associated with animals and their waste. VOC ratios can be potentially used as indicators for the separation of emissions from dairy and beef cattle from the regional aircraft measurements.

Reverse osmosis brine for phosphorus recovery from source separated urine.

Science.gov (United States)

Tian, Xiujun; Wang, Guotian; Guan, Detian; Li, Jiuyi; Wang, Aimin; Li, Jin; Yu, Zhe; Chen, Yong; Zhang, Zhongguo

2016-12-01

Phosphorus (P) recovery from waste streams has recently been recognized as a key step in the sustainable supply of this indispensable and non-renewable resource. The feasibility of using brine from a reverse osmosis (RO) membrane unit treating cooling water as a precipitant for P recovery from source separated urine was evaluated in the present study. P removal efficiency, process parameters and precipitate properties were investigated in batch and continuous flow experiments. More than 90% of P removal was obtained from both undiluted fresh and hydrolyzed urines by mixing with RO brine (1:1, v/v) at a pH over 9.0. Around 2.58 and 1.24 Kg of precipitates could be recovered from 1 m 3 hydrolyzed and fresh urine, respectively, and the precipitated solids contain 8.1-19.0% of P, 10.3-15.2% of Ca, 3.7-5.0% of Mg and 0.1-3.5% of ammonium nitrogen. Satisfactory P removal performance was also achieved in a continuous flow precipitation reactor with a hydraulic retention time of 3-6 h. RO brine could be considered as urinal and toilet flush water despite of a marginally higher precipitation tendency than tap water. This study provides a widely available, low - cost and efficient precipitant for P recovery in urban areas, which will make P recovery from urine more economically attractive. Copyright © 2016 Elsevier Ltd. All rights reserved.

Stable isotopes - separation and application

International Nuclear Information System (INIS)

Lockhart, I.M.

1980-01-01

In this review, methods used for the separation of stable isotopes ( 12 C, 13 C, 14 N, 15 N, 16 O, 17 O, 18 O, 34 S) will be described. The synthesis of labelled compounds, techniques for detection and assay, and areas of application will also be discussed. Particular attention will be paid to the isotopes of carbon, nitrogen, and oxygen; to date, sulphur isotopes have only assumed a minor role. The field of deuterium chemistry is too extensive for adequate treatment; it will therefore be essentially excluded. (author)

Global warming potential of material fractions occurring in source-separated organic household waste treated by anaerobic digestion or incineration under different framework conditions

DEFF Research Database (Denmark)

Naroznova, Irina; Møller, Jacob; Scheutz, Charlotte

2016-01-01

This study compared the environmental profiles of anaerobic digestion (AD) and incineration, in relation to global warming potential (GWP), for treating individual material fractions that may occur in source-separated organic household waste (SSOHW). Different framework conditions representative...

Effects of Sleep on Word Pair Memory in Children – Separating Item and Source Memory Aspects

Directory of Open Access Journals (Sweden)

Jing-Yi Wang

2017-09-01

Full Text Available Word paired-associate learning is a well-established task to demonstrate sleep-dependent memory consolidation in adults as well as children. Sleep has also been proposed to benefit episodic features of memory, i.e., a memory for an event (item bound into the spatiotemporal context it has been experienced in (source. We aimed to explore if sleep enhances word pair memory in children by strengthening the episodic features of the memory, in particular. Sixty-one children (8–12 years studied two lists of word pairs with 1 h in between. Retrieval testing comprised cued recall of the target word of each word pair (item memory and recalling in which list the word pair had appeared in (source memory. Retrieval was tested either after 1 h (short retention interval or after 11 h, with this long retention interval covering either nocturnal sleep or daytime wakefulness. Compared with the wake interval, sleep enhanced separate recall of both word pairs and the lists per se, while recall of the combination of the word pair and the list it had appeared in remained unaffected by sleep. An additional comparison with adult controls (n = 37 suggested that item-source bound memory (combined recall of word pair and list is generally diminished in children. Our results argue against the view that the sleep-induced enhancement in paired-associate learning in children is a consequence of sleep specifically enhancing the episodic features of the memory representation. On the contrary, sleep in children might strengthen item and source representations in isolation, while leaving the episodic memory representations (item-source binding unaffected.

Online artifact removal for brain-computer interfaces using support vector machines and blind source separation.

Science.gov (United States)

Halder, Sebastian; Bensch, Michael; Mellinger, Jürgen; Bogdan, Martin; Kübler, Andrea; Birbaumer, Niels; Rosenstiel, Wolfgang

2007-01-01

We propose a combination of blind source separation (BSS) and independent component analysis (ICA) (signal decomposition into artifacts and nonartifacts) with support vector machines (SVMs) (automatic classification) that are designed for online usage. In order to select a suitable BSS/ICA method, three ICA algorithms (JADE, Infomax, and FastICA) and one BSS algorithm (AMUSE) are evaluated to determine their ability to isolate electromyographic (EMG) and electrooculographic (EOG) artifacts into individual components. An implementation of the selected BSS/ICA method with SVMs trained to classify EMG and EOG artifacts, which enables the usage of the method as a filter in measurements with online feedback, is described. This filter is evaluated on three BCI datasets as a proof-of-concept of the method.

Irradiated fuel by-product separation research in Canada

International Nuclear Information System (INIS)

Burston, M.

1984-01-01

Although no decision has been made to reprocess irradiated CANDU fuel, by-product separation research has recently been initiated in Canada because of its potential importance to Canadian research programs in advanced fuel cycles (especially U/Pu cycle development in the near term) and nuclear waste management. In addition, separated by-products could have a significant commercial potential. Demonstrated applications include: heat sources, gamma radiation sources, light sources, new materials for productions of other useful isotopes, etc. For illustrative purposes the calculated market value of by-products currently stored in irradiated CANDU fuel is approximately $210/kgU. Ontario Hydro has initiated a program to study the application of new separation technolgies, such as laser-based techniques and the plasma ion cyclotron resonance separation technique, to either augment and/or supplant the chemical extraction methods. The main goal is to develop new, more economical extraction methods in order to increase the magnitude of the advantages resulting from this approach to reprocessing. (author)

Ammonia producing engine utilizing oxygen separation

Science.gov (United States)

Easley, Jr., William Lanier; Coleman, Gerald Nelson [Petersborough, GB; Robel, Wade James [Peoria, IL

2008-12-16

A power system is provided having a power source, a first power source section with a first intake passage and a first exhaust passage, a second power source section with a second intake passage and a second exhaust passage, and an oxygen separator. The second intake passage may be fluidly isolated from the first intake passage.

Isotope separation by photoselective dissociative electron

International Nuclear Information System (INIS)

Stevens, C.G.

1978-01-01

A method of separating isotopes based on photoselective electron capture dissociation of molecules having an electron capture cross section dependence on the vibrational state of the molecule is described. A molecular isotope source material is irradiated to selectively excite those molecules containing a desired isotope to a predetermined vibrational state having associated therewith an electron capture energy region substantially non-overlapping with the electron capture energy ranges associated with the lowest vibration states of the molecules. The isotope source is also subjected to electrons having an energy corresponding to the non-overlapping electron capture region whereby the selectively excited molecules preferentially capture electrons and dissociate into negative ions and neutrals. The desired isotope may be in the negative ion product or in the neutral product depending upon the mechanism of dissociation of the particular isotope source used. The dissociation product enriched in the desired isotope is then separated from the reaction system by conventional means. Specifically, 235 UF 6 is separated from a UF 6 mixture by selective excitation followed by dissociative electron capture into 235 UF 5 - and F

Multiple-isotope separation in gas centrifuge

International Nuclear Information System (INIS)

Wood, Houston G.; Mason, T.C.; Soubbaramayer

1996-01-01

In previous works, the Onsager's pancake equation was used to provide solution to the internal counter-current flow field, which is necessary to calculate solutions to the isotope transport equation. The diffusion coefficient was assumed to be constant which is a good approximation for gases with large molecular weights, and small differences in the molecular weights of the various isotopes. A new optimization strategy was presented for determining the operating parameters of a gas centrifuge to be used for multiple-component isotope separation. Scoop drag, linear wall temperature gradient, the feed rate ant the cut have been chosen as operating parameters for the optimization. The investigation was restricted to a single centrifuge, and the problem of cascading for multiple-isotope separation was not addressed. The model describing the flow and separation phenomena in centrifuge includes a set of equations describing the fluid dynamics of the counter-current flow and the diffusion equations written for each isotope of the mixture. In this paper, an optimization algorithm is described and applied to an example for the re enrichment of spent reactor uranium

Preparing for creative responses to “beyond assumed level” disasters: lessons from the ICT management in the 2011 Great East Japan earthquake crisis

Directory of Open Access Journals (Sweden)

Mihoko Sakurai

2012-12-01

Full Text Available A survey of the municipal government ICT divisions during and after the 2011 Great East Japan Earthquake and Tsunami crisis reveals the need for creative responses for “beyond assumed level” disasters. Complexity and diversity of the damage were simply too great for any plans to assume. Resident needs toward the municipal governments were also diverse and changed quickly as the time went by. The research also indicates that there would be ways to strengthen the capabilities to execute such spontaneous responses. Creative solutions executed during the 3.11 crisis were supported by the existence of open source software available on the net and skilled engineers that were capable of exploiting them. Frugal information system will be useful to improve preparedness for creative responses

Treatment of Source-Separated Blackwater: A Decentralized Strategy for Nutrient Recovery towards a Circular Economy

Directory of Open Access Journals (Sweden)

Melesse Eshetu Moges

2018-04-01

Full Text Available Using a filter medium for organic matter removal and nutrient recovery from blackwater treatment is a novel concept and has not been investigated sufficiently to date. This paper demonstrates a combined blackwater treatment and nutrient-recovery strategy and establishes mechanisms for a more dependable source of plant nutrients aiming at a circular economy. Source-separated blackwater from a student dormitory was used as feedstock for a sludge blanket anaerobic-baffled reactor. The effluent from the reactor, with 710 mg L−1 NH4–N and 63 mg L−1 PO4–P, was treated in a sequence of upflow and downflow filtration columns using granular activated carbon, Cocos char and polonite as filter media at a flow rate of 600 L m−2 day−1 and organic loading rate of 430 g chemical oxygen demand (COD m−2 day−1. Filtration treatment of the anaerobic effluent with carbon adsorbents removed 80% of the residual organic matter, more than 90% of suspended solids, and turbidity while releasing more than 76% NH4–N and 85% of PO4–P in the liquid phase. The treatment train also removed total coliform bacteria and E. coli in the effluent, achieving concentrations below detection limit after the integration of ultraviolet (UV light. These integrated technological pathways ensure simultaneous nutrient recovery as a nutrient solution, pathogen inactivation, and reduction of active organic substances. The treated nutrient-rich water can be applied as a source of value creation for various end-use options.

A New Concept for Counter-Checking of Assumed CPM Pairs

Science.gov (United States)

Knapp, Wilfried; Nanson, John

2017-01-01

The inflation of “newly discovered” CPM pairs makes it necessary to develop an approach for a solid concept for counter-checking assumed CPM pairs with the target to identify false positives. Such a concept is presented in this report.

Review of Membranes for Helium Separation and Purification

Directory of Open Access Journals (Sweden)

Colin A. Scholes

2017-02-01

Full Text Available Membrane gas separation has potential for the recovery and purification of helium, because the majority of membranes have selectivity for helium. This review reports on the current state of the research and patent literature for membranes undertaking helium separation. This includes direct recovery from natural gas, as an ancillary stage in natural gas processing, as well as niche applications where helium recycling has potential. A review of the available polymeric and inorganic membranes for helium separation is provided. Commercial gas separation membranes in comparable gas industries are discussed in terms of their potential in helium separation. Also presented are the various membrane process designs patented for the recovery and purification of helium from various sources, as these demonstrate that it is viable to separate helium through currently available polymeric membranes. This review places a particular focus on those processes where membranes are combined in series with another separation technology, commonly pressure swing adsorption. These combined processes have the most potential for membranes to produce a high purity helium product. The review demonstrates that membrane gas separation is technically feasible for helium recovery and purification, though membranes are currently only applied in niche applications focused on reusing helium rather than separation from natural sources.

Accessibility versus accuracy in retrieving spatial memory: evidence for suboptimal assumed headings.

Science.gov (United States)

Yerramsetti, Ashok; Marchette, Steven A; Shelton, Amy L

2013-07-01

Orientation dependence in spatial memory has often been interpreted in terms of accessibility: Object locations are encoded relative to a reference orientation that affords the most accurate access to spatial memory. An open question, however, is whether people naturally use this "preferred" orientation whenever recalling the space. We tested this question by asking participants to locate buildings on a familiar campus from various imagined locations, without specifying the heading to be assumed. We then used these pointing judgments to infer the approximate heading participants assumed at each location. Surprisingly, each location showed a unique assumed heading that was consistent across participants and seemed to reflect episodic or visual properties of the space. This result suggests that although locations are encoded relative to a reference orientation, other factors may influence how people choose to access the stored information and whether they appeal to long-term spatial memory or other more sensory-based stores. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Method and apparatus for separating isotopes

International Nuclear Information System (INIS)

Harris, S.E.

1976-01-01

Isotope separation is achieved between species A and B having an absorption resonance separated by an isotopic shift by selectively exciting a portion of species A using a tunable photon source of narrow emission line with and subsequently causing collisions with an optically excited third species to selectively ionize the excited portion of species A. When ionized, species A is easily separated by any technique, using its ionized condition to distinguish it from species B. 18 claims, 3 drawing figures

Subjective and Objective Quality Assessment of Single-Channel Speech Separation Algorithms

DEFF Research Database (Denmark)

Mowlaee, Pejman; Saeidi, Rahim; Christensen, Mads Græsbøll

2012-01-01

Previous studies on performance evaluation of single-channel speech separation (SCSS) algorithms mostly focused on automatic speech recognition (ASR) accuracy as their performance measure. Assessing the separated signals by different metrics other than this has the benefit that the results...... are expected to carry on to other applications beyond ASR. In this paper, in addition to conventional speech quality metrics (PESQ and SNRloss), we also evaluate the separation systems output using different source separation metrics: blind source separation evaluation (BSS EVAL) and perceptual evaluation...... that PESQ and PEASS quality metrics predict well the subjective quality of separated signals obtained by the separation systems. From the results it is observed that the short-time objective intelligibility (STOI) measure predict the speech intelligibility results....

Some considerations on displacement assumed finite elements with the reduced numerical integration technique

International Nuclear Information System (INIS)

Takeda, H.; Isha, H.

1981-01-01

The paper is concerned with the displacement-assumed-finite elements by applying the reduced numerical integration technique in structural problems. The first part is a general consideration on the technique. Its purpose is to examine a variational interpretation of the finite element displacement formulation with the reduced integration technique in structural problems. The formulation is critically studied from a standpoint of the natural stiffness approach. It is shown that these types of elements are equivalent to a certain type of displacement and stress assumed mixed elements. The rank deficiency of the stiffness matrix of these elements is interpreted as a problem in the transformation from the natural system to a Cartesian system. It will be shown that a variational basis of the equivalent mixed formulation is closely related to the Hellinger-Reissner's functional. It is presented that for simple elements, e.g. bilinear quadrilateral plane stress and plate bending there are corresponding mixed elements from the functional. For relatively complex types of these elements, it is shown that they are equivalent to localized mixed elements from the Hellinger-Reissner's functional. In the second part, typical finite elements with the reduced integration technique are studied to demonstrate this equivalence. A bilinear displacement and rotation assumed shear beam element, a bilinear displacement assumed quadrilateral plane stress element and a bilinear deflection and rotation assumed quadrilateral plate bending element are examined to present equivalent mixed elements. Not only the theoretical consideration is presented but numerical studies are shown to demonstrate the effectiveness of these elements in practical analysis. (orig.)

13 CFR 120.1718 - SBA's right to assume Seller's responsibilities.

Science.gov (United States)

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false SBA's right to assume Seller's responsibilities. 120.1718 Section 120.1718 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Establishment of SBA Secondary Market Guarantee Program for First Lien Position 504 Loan Pools...

Assumed Probability Density Functions for Shallow and Deep Convection

OpenAIRE

Steven K Krueger; Peter A Bogenschutz; Marat Khairoutdinov

2010-01-01

The assumed joint probability density function (PDF) between vertical velocity and conserved temperature and total water scalars has been suggested to be a relatively computationally inexpensive and unified subgrid-scale (SGS) parameterization for boundary layer clouds and turbulent moments. This paper analyzes the performance of five families of PDFs using large-eddy simulations of deep convection, shallow convection, and a transition from stratocumulus to trade wind cumulus. Three of the PD...

Jobs, sex, love and lifestyle: when nonstutterers assume the roles of stutterers.

Science.gov (United States)

Zhang, Jianliang; Saltuklaroglu, Tim; Hough, Monica; Kalinowski, Joseph

2009-01-01

This study assessed the impact of stuttering via a questionnaire in which fluent individuals were asked to assume the mindset of persons who stutter (PWS) in various life aspects, including vocation, romance, daily activities, friends/social life, family and general lifestyle. The perceived impact of stuttering through the mind's eyes of nonstutterers is supposed to reflect respondents' abilities to impart 'theory of mind' in addressing social penalties related to stuttering. Ninety-one university students answered a questionnaire containing 56 statements on a 7-point Likert scale. Forty-four participants (mean age = 20.4, SD = 4.4) were randomly selected to assume a stuttering identity and 47 respondents (mean age = 20.5, SD = 3.1) to assume their normally fluent identity. Significant differences between groups were found in more than two thirds of items regarding employment, romance, and daily activities, and in fewer than half of items regarding family, friend/social life, and general life style (p role of PWS, are capable of at least temporarily feeling the negative impact of stuttering. Copyright 2008 S. Karger AG, Basel.

Technical clarification to Silbert and Thomas (2013): "decisional separability, model identification, and statistical inference in the general recognition theory framework".

Science.gov (United States)

Thomas, Robin D; Silbert, Noah H

2014-04-01

We offer a minor technical correction to the published proof of part (ii) of the main theorem in Silbert and Thomas (Psychonomic Bulletin & Review, 20, 1-20, 2013) that somewhat limits the scope of the equivalence observed in that work. Specifically, in order for a mean shift integrality with decisional separability to be mimicked by a perceptually separable but nondecisionally separable configuration, one needs to assume stimulus invariance. This holds when all of the covariance matrices in the stimulus configuration are equal to each other. We note that part (i) of the theorem is unaffected by this modification; an empirical finding of perceptual separability and the failure of decisional separability can be mimicked by a perceptually nonseparable, decisionally separable configuration without restricting the covariance matrices to be equal. We also note that stimulus invariance is often assumed in simple designs (e.g., Macmillan & Ornstein in Journal of the Acoustical Society of America, 97, 1261-1285, 1998), due to the implausibility of different perceptual correlations being present within stimuli perched very closely in perceptual space.

Developing methodologies for source attribution. Glass phase separation in Trinitite using NF{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Koeman, Elizabeth C.; Simonetti, Antonio [Notre Dame Univ., IN (United States). Dept. of Civil and Environmental Engineering and Earth Sciences; McNamara, Bruce K.; Smith, Frances N. [Pacific Northwest National Laboratory, Richland, WA (United States). Nuclear Chemistry and Engineering; Burns, Peter C. [Notre Dame Univ., IN (United States). Dept. of Civil and Environmental Engineering and Earth Sciences; Notre Dame Univ., IN (United States). Dept. of Chemistry and Biochemistry

2017-08-01

separation of silica from minerals (i.e. naturally occurring crystalline materials) and glasses (i.e. amorphous materials), leaving behind non-volatile fluorinated species and refractory phases. The results from our investigation clearly indicate that the NF{sub 3} treatment of nuclear materials is a technique that provides effective separation of bomb components from complex matrices (e.g. post-detonation samples), which will aid with rapid and accurate source attribution.

Monitoring Assumptions in Assume-Guarantee Contracts

Directory of Open Access Journals (Sweden)

Oleg Sokolsky

2016-05-01

Full Text Available Pre-deployment verification of software components with respect to behavioral specifications in the assume-guarantee form does not, in general, guarantee absence of errors at run time. This is because assumptions about the environment cannot be discharged until the environment is fixed. An intuitive approach is to complement pre-deployment verification of guarantees, up to the assumptions, with post-deployment monitoring of environment behavior to check that the assumptions are satisfied at run time. Such a monitor is typically implemented by instrumenting the application code of the component. An additional challenge for the monitoring step is that environment behaviors are typically obtained through an I/O library, which may alter the component's view of the input format. This transformation requires us to introduce a second pre-deployment verification step to ensure that alarms raised by the monitor would indeed correspond to violations of the environment assumptions. In this paper, we describe an approach for constructing monitors and verifying them against the component assumption. We also discuss limitations of instrumentation-based monitoring and potential ways to overcome it.

'Americium(III)/trivalent lanthanides' separation using organothiophosphinic acids

International Nuclear Information System (INIS)

Hill, C.; Madic, C.; Baron, P.; Ozawa, Masaki; Tanaka, Yasumasa.

1997-01-01

The present paper describes the extraction of neodymium and other lanthanides by saponified Cyanex 301 acid. The saponification of commercial Cyanex 301 acid favoured the extraction of macro concentrations of neodymium from sodium nitrate aqueous solutions (pH eq ∼ 4). The amount of lanthanide extracted in the organic phase always reached the third of the initial concentration of saponified Cyanex 301 acid, which assumed a cation exchange mechanism to occur during the extraction. No nitrate anion took part in the complex formation. This paper also compares the abilities of purified Cyanex 301, Cyanex 302 and Cyanex 272 acids to extract and separate 241 Am(III) from 152 Eu(III). Very high separation factors S.F. Am/Eu were observed in the case of purified Cyanex 301 acid. Finally some studies are presented herein using tri-n-butylphosphate (TBP) as a synergistic extractant with Cyanex 301 acid to separate actinides from trivalent lanthanide. (author)

24 CFR 1000.20 - Is an Indian tribe required to assume environmental review responsibilities?

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Is an Indian tribe required to assume environmental review responsibilities? 1000.20 Section 1000.20 Housing and Urban Development... § 1000.20 Is an Indian tribe required to assume environmental review responsibilities? (a) No. It is an...

Direct electrochemical oxidation of ammonia on graphite as a treatment option for stored source-separated urine.

Science.gov (United States)

Zöllig, Hanspeter; Fritzsche, Cristina; Morgenroth, Eberhard; Udert, Kai M

2015-02-01

Electrolysis can be a viable technology for ammonia removal from source-separated urine. Compared to biological nitrogen removal, electrolysis is more robust and is highly amenable to automation, which makes it especially attractive for on-site reactors. In electrolytic wastewater treatment, ammonia is usually removed by indirect oxidation through active chlorine which is produced in-situ at elevated anode potentials. However, the evolution of chlorine can lead to the formation of chlorate, perchlorate, chlorinated organic by-products and chloramines that are toxic. This study focuses on using direct ammonia oxidation on graphite at low anode potentials in order to overcome the formation of toxic by-products. With the aid of cyclic voltammetry, we demonstrated that graphite is active for direct ammonia oxidation without concomitant chlorine formation if the anode potential is between 1.1 and 1.6 V vs. SHE (standard hydrogen electrode). A comparison of potentiostatic bulk electrolysis experiments in synthetic stored urine with and without chloride confirmed that ammonia was removed exclusively by continuous direct oxidation. Direct oxidation required high pH values (pH > 9) because free ammonia was the actual reactant. In real stored urine (pH = 9.0), an ammonia removal rate of 2.9 ± 0.3 gN·m(-2)·d(-1) was achieved and the specific energy demand was 42 Wh·gN(-1) at an anode potential of 1.31 V vs. SHE. The measurements of chlorate and perchlorate as well as selected chlorinated organic by-products confirmed that no chlorinated by-products were formed in real urine. Electrode corrosion through graphite exfoliation was prevented and the surface was not poisoned by intermediate oxidation products. We conclude that direct ammonia oxidation on graphite electrodes is a treatment option for source-separated urine with three major advantages: The formation of chlorinated by-products is prevented, less energy is consumed than in indirect ammonia oxidation and

Mass transfer apparatus and method for separation of gases

Energy Technology Data Exchange (ETDEWEB)

Blount, Gerald C.; Gorensek, Maximilian Boris; Hamm, Luther L.

2018-01-16

A process and apparatus for separating components of a source gas is provided in which more soluble components of the source gas are dissolved in an aqueous solvent at high pressure. The system can utilize hydrostatic pressure to increase solubility of the components of the source gas. The apparatus includes gas recycle throughout multiple mass transfer stages to improve mass transfer of the targeted components from the liquid to gas phase. Separated components can be recovered for use in a value added application or can be processed for long-term storage, for instance in an underwater reservoir.

An investigation of the usability of sound recognition for source separation of packaging wastes in reverse vending machines.

Science.gov (United States)

Korucu, M Kemal; Kaplan, Özgür; Büyük, Osman; Güllü, M Kemal

2016-10-01

In this study, we investigate the usability of sound recognition for source separation of packaging wastes in reverse vending machines (RVMs). For this purpose, an experimental setup equipped with a sound recording mechanism was prepared. Packaging waste sounds generated by three physical impacts such as free falling, pneumatic hitting and hydraulic crushing were separately recorded using two different microphones. To classify the waste types and sizes based on sound features of the wastes, a support vector machine (SVM) and a hidden Markov model (HMM) based sound classification systems were developed. In the basic experimental setup in which only free falling impact type was considered, SVM and HMM systems provided 100% classification accuracy for both microphones. In the expanded experimental setup which includes all three impact types, material type classification accuracies were 96.5% for dynamic microphone and 97.7% for condenser microphone. When both the material type and the size of the wastes were classified, the accuracy was 88.6% for the microphones. The modeling studies indicated that hydraulic crushing impact type recordings were very noisy for an effective sound recognition application. In the detailed analysis of the recognition errors, it was observed that most of the errors occurred in the hitting impact type. According to the experimental results, it can be said that the proposed novel approach for the separation of packaging wastes could provide a high classification performance for RVMs. Copyright © 2016 Elsevier Ltd. All rights reserved.

Measurement of the distributions of internuclear separations in 3.0-MeV H2+ and 3.63-MeV HeH+ beams

International Nuclear Information System (INIS)

Kanter, E.P.; Cooney, P.J.; Gemmell, D.S.; Vager, Z.; Pietsch, W.J.; Zabransky, B.J.

1979-01-01

Angular distributions of charged dissociation fragments are measured for 3.0-MeV H 2 + and 3.63-MeV HeH + ions incident on approx. 160 A carbon targets. By using the reflection method for a pure Coulomb potential, there are unfolded from these data the distributions of internuclear separations for each molecular-ion species prior to dissociation. These results are insensitive to ion-source conditions. For H 2 + this distribution, while approx. 2 times wider than a pure ground vibrational state population, is markedly different from the Franck-Condon distribution that has been previously assumed by other authors with similar rf and duo-plasmatron ion sources. For HeH + the distribution is slightly broader (approx. 1.5 times) than that expected for a pure ground state population. From the data, the initial vibrational state population in the incident beam can be extracted. 11 references

Asynchronous variational integration using continuous assumed gradient elements.

Science.gov (United States)

Wolff, Sebastian; Bucher, Christian

2013-03-01

Asynchronous variational integration (AVI) is a tool which improves the numerical efficiency of explicit time stepping schemes when applied to finite element meshes with local spatial refinement. This is achieved by associating an individual time step length to each spatial domain. Furthermore, long-term stability is ensured by its variational structure. This article presents AVI in the context of finite elements based on a weakened weak form (W2) Liu (2009) [1], exemplified by continuous assumed gradient elements Wolff and Bucher (2011) [2]. The article presents the main ideas of the modified AVI, gives implementation notes and a recipe for estimating the critical time step.

Anaerobic treatment as a core technology for energy, nutrients and water recovery from source-separated domestic waste(water).

Science.gov (United States)

Zeeman, Grietje; Kujawa, Katarzyna; de Mes, Titia; Hernandez, Lucia; de Graaff, Marthe; Abu-Ghunmi, Lina; Mels, Adriaan; Meulman, Brendo; Temmink, Hardy; Buisman, Cees; van Lier, Jules; Lettinga, Gatze

2008-01-01

Based on results of pilot scale research with source-separated black water (BW) and grey water (GW), a new sanitation concept is proposed. BW and GW are both treated in a UASB (-septic tank) for recovery of CH4 gas. Kitchen waste is added to the anaerobic BW treatment for doubling the biogas production. Post-treatment of the effluent is providing recovery of phosphorus and removal of remaining COD and nitrogen. The total energy saving of the new sanitation concept amounts to 200 MJ/year in comparison with conventional sanitation, moreover 0.14 kg P/p/year and 90 litres of potential reusable water are produced. (c) IWA Publishing 2008.

Spark-safe power source

Energy Technology Data Exchange (ETDEWEB)

Mester, I M; Konushkin, N A; Nevozinskiy, A K; Rubinshteyn, B Sh; Serov, V I; Vasnev, M A

1981-01-01

A shortcoming of the known power sources is their low reliability. The purpose of the invention is to improve the reliability of the device. This is achieved because the spark-safe power source is equipped with a by-passing transistor and potentiometer, and also a generator of control interruptions in the circuit, an I-element, first separating transformer, control block, second separating transformer whose secondary winding has a relay winding whose contacts are connected to the load circuit are connected in series. The generator of control separations of the circuit is connected to the base of the by-passing transistor and to the power source outlet, the potentiometer is connected in series to the main thyristor. The middle point of the potentiometer is connected to the second inlet of the I-element.

Air separation by pressure swing adsorption on a carbon molecular sieve

Energy Technology Data Exchange (ETDEWEB)

Hassan, M M; Ruthven, D M; Raghaven, N S

1986-01-01

A simplified dynamic model for a PSA air separation process is developed based on linearized mass transfer rate expressions and binary Langmuir equilibrium. Constant pressure is assumed during adsorption and desorption steps but the variation in flow rate through the column due to adsorption is accounted for. The model predictions, using independently measured kinetic and equilibrium data are compared with experimental results obtained in a simple two-bed air separation PSA system packed with a carbon molecular sieve adsorbent. The model is shown to provide a good representation of the experimentally observed behavior over a wide range of conditions.

Novel PEFC Application for Deuterium Isotope Separation

Directory of Open Access Journals (Sweden)

Hisayoshi Matsushima

2017-03-01

Full Text Available The use of a polymer electrolyte fuel cell (PEFC with a Nafion membrane for isotopic separation of deuterium (D was investigated. Mass analysis at the cathode side indicated that D diffused through the membrane and participated in an isotope exchange reaction. The exchange of D with protium (H in H2O was facilitated by a Pt catalyst. The anodic data showed that the separation efficiency was dependent on the D concentration in the source gas, whereby the water produced during the operation of the PEFC was more enriched in D as the D concentration of the source gas was increased.

Formulas for Rational-Valued Separability Probabilities of Random Induced Generalized Two-Qubit States

Directory of Open Access Journals (Sweden)

Paul B. Slater

2015-01-01

Full Text Available Previously, a formula, incorporating a 5F4 hypergeometric function, for the Hilbert-Schmidt-averaged determinantal moments ρPTnρk/ρk of 4×4 density-matrices (ρ and their partial transposes (|ρPT|, was applied with k=0 to the generalized two-qubit separability probability question. The formula can, furthermore, be viewed, as we note here, as an averaging over “induced measures in the space of mixed quantum states.” The associated induced-measure separability probabilities (k=1,2,… are found—via a high-precision density approximation procedure—to assume interesting, relatively simple rational values in the two-re[al]bit (α=1/2, (standard two-qubit (α=1, and two-quater[nionic]bit (α=2 cases. We deduce rather simple companion (rebit, qubit, quaterbit, … formulas that successfully reproduce the rational values assumed for general  k. These formulas are observed to share certain features, possibly allowing them to be incorporated into a single master formula.

The Effect on Treatment Adherence of Administering Drugs as Fixed-Dose Combinations versus as Separate Pills: Systematic Review and Meta-Analysis

NARCIS (Netherlands)

van Galen, Katy A.; Nellen, Jeannine F.; Nieuwkerk, Pythia T.

2014-01-01

Administering drugs as fixed-dose combinations (FDCs) versus the same active drugs administered as separate pills is assumed to enhance treatment adherence. We synthesized evidence from randomized controlled trials (RCTs) about the effect of FDCs versus separate pills on adherence. We searched

Paired organs--Should they be treated jointly or separately in internal dosimetry?

Energy Technology Data Exchange (ETDEWEB)

Parach, Ali-Asghar; Rajabi, Hossein; Askari, Mohammad-Ali [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran-Iran (Iran, Islamic Republic of)

2011-10-15

Purpose: Size, shape, and the position of paired organs are different in abdomen. However, the counterpart organs are conventionally treated jointly together in internal dosimetry. This study was performed to quantify the difference of specific absorbed fraction of organs in considering paired organs jointly like single organs or as two separate organs. Methods: Zubal phantom and GATE Monte Carlo package were used to calculate the SAF for the self-absorption and cross-irradiation of the lungs, kidneys, adrenal glands (paired organs), liver, spleen, stomach, and pancreas (single organs). The activity was assumed uniformly distributed in the organs, and simulation was performed for monoenergetic photons of 10, 50, 100, 500, 1000 keV and mono-energetic electrons of 350, 500, 690, 935, 1200 keV. Results: The results demonstrated that self-absorption of left and right counterpart organs may be different depending upon the differences in their masses. The cross-irradiations between left-to-right and right-to-left counterpart organs are always equal irrespective of difference in their masses. Cross-irradiation from the left and right counterpart organs to other organs are different (4-24 times in Zubal phantom) depending on the photon energy and organs. The irradiation from a single source organ to the left and right counterpart paired organs is always different irrespective of activity concentration. Conclusions: Left and right counterpart organs always receive different absorbed doses from target organs and deliver different absorbed doses to target organs. Therefore, in application of radiopharmaceuticals in which the dose to the organs plays a role, counterpart organs should be treated separately as two separate organs.

Paired organs--Should they be treated jointly or separately in internal dosimetry?

International Nuclear Information System (INIS)

Parach, Ali-Asghar; Rajabi, Hossein; Askari, Mohammad-Ali

2011-01-01

Purpose: Size, shape, and the position of paired organs are different in abdomen. However, the counterpart organs are conventionally treated jointly together in internal dosimetry. This study was performed to quantify the difference of specific absorbed fraction of organs in considering paired organs jointly like single organs or as two separate organs. Methods: Zubal phantom and GATE Monte Carlo package were used to calculate the SAF for the self-absorption and cross-irradiation of the lungs, kidneys, adrenal glands (paired organs), liver, spleen, stomach, and pancreas (single organs). The activity was assumed uniformly distributed in the organs, and simulation was performed for monoenergetic photons of 10, 50, 100, 500, 1000 keV and mono-energetic electrons of 350, 500, 690, 935, 1200 keV. Results: The results demonstrated that self-absorption of left and right counterpart organs may be different depending upon the differences in their masses. The cross-irradiations between left-to-right and right-to-left counterpart organs are always equal irrespective of difference in their masses. Cross-irradiation from the left and right counterpart organs to other organs are different (4-24 times in Zubal phantom) depending on the photon energy and organs. The irradiation from a single source organ to the left and right counterpart paired organs is always different irrespective of activity concentration. Conclusions: Left and right counterpart organs always receive different absorbed doses from target organs and deliver different absorbed doses to target organs. Therefore, in application of radiopharmaceuticals in which the dose to the organs plays a role, counterpart organs should be treated separately as two separate organs.

Retrieval of source parameters of an event of the 2000 West Bohemia earthquake swarm assuming an anisotropic crust

Czech Academy of Sciences Publication Activity Database

Rössler, D.; Krüger, F.; Pšenčík, Ivan; Rümpker, G.

2007-01-01

Roč. 51, č. 2 (2007), s. 231-254 ISSN 0039-3169 R&D Projects: GA AV ČR IAA300120502 Grant - others:DFG(DE) KR1935/1-1; DFG(DE) KR1935/1-3 Institutional research plan: CEZ:AV0Z30120515 Keywords : seismic source * tensile faulting * seismic anisotropy * West Bohemia Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 0.733, year: 2007

Complete nutrient recovery from source-separated urine by nitrification and distillation.

Science.gov (United States)

Udert, K M; Wächter, M

2012-02-01

In this study we present a method to recover all nutrients from source-separated urine in a dry solid by combining biological nitrification with distillation. In a first process step, a membrane-aerated biofilm reactor was operated stably for more than 12 months, producing a nutrient solution with a pH between 6.2 and 7.0 (depending on the pH set-point), and an ammonium to nitrate ratio between 0.87 and 1.15 gN gN(-1). The maximum nitrification rate was 1.8 ± 0.3 gN m(-2) d(-1). Process stability was achieved by controlling the pH via the influent. In the second process step, real nitrified urine and synthetic solutions were concentrated in lab-scale distillation reactors. All nutrients were recovered in a dry powder except for some ammonia (less than 3% of total nitrogen). We estimate that the primary energy demand for a simple nitrification/distillation process is four to five times higher than removing nitrogen and phosphorus in a conventional wastewater treatment plant and producing the equivalent amount of phosphorus and nitrogen fertilizers. However, the primary energy demand can be reduced to values very close to conventional treatment, if 80% of the water is removed with reverse osmosis and distillation is operated with vapor compression. The ammonium nitrate content of the solid residue is below the limit at which stringent EU safety regulations for fertilizers come into effect; nevertheless, we propose some additional process steps that will increase the thermal stability of the solid product. Copyright © 2011 Elsevier Ltd. All rights reserved.

Estimation of nitrite in source-separated nitrified urine with UV spectrophotometry.

Science.gov (United States)

Mašić, Alma; Santos, Ana T L; Etter, Bastian; Udert, Kai M; Villez, Kris

2015-11-15

Monitoring of nitrite is essential for an immediate response and prevention of irreversible failure of decentralized biological urine nitrification reactors. Although a few sensors are available for nitrite measurement, none of them are suitable for applications in which both nitrite and nitrate are present in very high concentrations. Such is the case in collected source-separated urine, stabilized by nitrification for long-term storage. Ultraviolet (UV) spectrophotometry in combination with chemometrics is a promising option for monitoring of nitrite. In this study, an immersible in situ UV sensor is investigated for the first time so to establish a relationship between UV absorbance spectra and nitrite concentrations in nitrified urine. The study focuses on the effects of suspended particles and saturation on the absorbance spectra and the chemometric model performance. Detailed analysis indicates that suspended particles in nitrified urine have a negligible effect on nitrite estimation, concluding that sample filtration is not necessary as pretreatment. In contrast, saturation due to very high concentrations affects the model performance severely, suggesting dilution as an essential sample preparation step. However, this can also be mitigated by simple removal of the saturated, lower end of the UV absorbance spectra, and extraction of information from the secondary, weaker nitrite absorbance peak. This approach allows for estimation of nitrite with a simple chemometric model and without sample dilution. These results are promising for a practical application of the UV sensor as an in situ nitrite measurement in a urine nitrification reactor given the exceptional quality of the nitrite estimates in comparison to previous studies. Copyright © 2015 Elsevier Ltd. All rights reserved.

Separable potential approach in the folding model. Pt. 2

International Nuclear Information System (INIS)

Lee, C.L.; Robson, D.

1982-01-01

A microscopic folding formalism using a separable potential approach is applied to the elastic scattering of the n-α system. Starting with a separable nucleon-nucleon (NN) potential model, a sum of separable nucleon-nucleus potentials is obtained. A simple structure of the α-particle is assumed and the Tabakin, the Doleschall and the Strobel NN potentials are considered. These phenomenological interactions are of Yukawa or gaussian form with variable parameters for each partial wave. Spin-orbit and tensor forces are included. The resulting potentials developed from our folding calculations give approximately the same ssub(1/2) phase shifts for the n-α elastic scattering. However, in the psub(1/2) and psub(3/2) phase-shift analysis, an effective interaction derived from the NN potential is necessary to reproduce the resonances. One free energy independent parameter is introduced in our approximate G-matrix concept to give a good fit for the phase shifts. Single-nucleon knockout exchange (SNKE) is considered throughout. (orig.)

Industrial treatment of solutions of fission products. Separation of caesium-137; Traitement industriel de solutions de produits de fission. Separation du cesium-137

Energy Technology Data Exchange (ETDEWEB)

Fisher, C; Raggenbass, A [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1959-07-01

Two types of chemical treatment can be considered for the manufacture of solid sources for industrial uses from fission product solutions remaining after plutonium extraction: a) concentration of the solution and preparation of solid sources from the bulk material, without separation, b) separation of one or several fission products from which the sources are made. Examination of the radio-chemical composition of the mixture of fission products that will be available from the Marcoule reactors (G1, G2 and G3) shows that caesium-137 accounts for 30 per cent of the {gamma} energy available immediately after the plutonium separation, 70 per cent two years after and 100 per cent after five years. There is practically no advantage in making sources from bulk fission products, since the separation of caesium-137 is no more complicated and yet it results in a material with more potential uses. The separation of caesium-137 by a method based on the standard phospho-tungstate precipitation method has been considered. Previously, the precipitated caesium phospho-tungstate was dissolved and caesium was recovered from the solution by cation-exchange or by removal of phosphate and tungstate ions by anion-exchange. A study has now been made, of the metathesis of caesium phospho-tungstate to barium phosphate and tungstate by the action of barium hydroxide, the caesium being obtained in solution as the hydroxide. The advantages of this new procedure are: - greater decontamination of caesium-137 without further purification, - possibility of direct transformation to caesium sulphate, - general simplification of the procedure and, consequently, of the equipment. (author) [French] Deux types de traitement chimique peuvent etre envisages pour amener a l'etat de sources solides utilisables industriellement les produits de fission contenus dans les solutions residuaires de l'extraction du plutonium. Ces traitements sont les suivants: a) concentration des solutions et confection de

Industrial treatment of solutions of fission products. Separation of caesium-137; Traitement industriel de solutions de produits de fission. Separation du cesium-137

Energy Technology Data Exchange (ETDEWEB)

Fisher, C.; Raggenbass, A. [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1959-07-01

Two types of chemical treatment can be considered for the manufacture of solid sources for industrial uses from fission product solutions remaining after plutonium extraction: a) concentration of the solution and preparation of solid sources from the bulk material, without separation, b) separation of one or several fission products from which the sources are made. Examination of the radio-chemical composition of the mixture of fission products that will be available from the Marcoule reactors (G1, G2 and G3) shows that caesium-137 accounts for 30 per cent of the {gamma} energy available immediately after the plutonium separation, 70 per cent two years after and 100 per cent after five years. There is practically no advantage in making sources from bulk fission products, since the separation of caesium-137 is no more complicated and yet it results in a material with more potential uses. The separation of caesium-137 by a method based on the standard phospho-tungstate precipitation method has been considered. Previously, the precipitated caesium phospho-tungstate was dissolved and caesium was recovered from the solution by cation-exchange or by removal of phosphate and tungstate ions by anion-exchange. A study has now been made, of the metathesis of caesium phospho-tungstate to barium phosphate and tungstate by the action of barium hydroxide, the caesium being obtained in solution as the hydroxide. The advantages of this new procedure are: - greater decontamination of caesium-137 without further purification, - possibility of direct transformation to caesium sulphate, - general simplification of the procedure and, consequently, of the equipment. (author) [French] Deux types de traitement chimique peuvent etre envisages pour amener a l'etat de sources solides utilisables industriellement les produits de fission contenus dans les solutions residuaires de l'extraction du plutonium. Ces traitements sont les suivants: a) concentration des solutions et

Rapid ion-exchange separations of actinides

International Nuclear Information System (INIS)

Usuda, Shigekazu

1988-01-01

For the purpose of studying short-lived actinide nuclides, three methods for rapid ion exchange separation of actinide elements with mineral acid-alcohol mixed media were developed: anion exchange with nitric acid-methyl alcohol mixed media to separate the transplutonium and rare earth elements from target material, U or Pu and Al catcher foils; anion exchange with hydrochloric acid-methyl alcohol media to separate Am+Cm, Bk and Cf+Fm from the target, catcher foils and major fission products; and cation exchange with hydrochloric acid-methyl alcohol media and with concentrated hydrochloric acid to separate the transplutonium elements as a group from the rare earths after eliminating the large amounts of U, Al, Cu, Fe etc. The methods enable one to perform rapid and effective separation at elevated temperature (90 deg C) and immediate source preparation for alpha-ray spectrometry. (author) 47 refs.; 10 figs

An Analytical Threshold Voltage Model of Fully Depleted (FD) Recessed-Source/Drain (Re-S/D) SOI MOSFETs with Back-Gate Control

Science.gov (United States)

Saramekala, Gopi Krishna; Tiwari, Pramod Kumar

2016-10-01

This paper presents an analytical threshold voltage model for back-gated fully depleted (FD), recessed-source drain silicon-on-insulator metal-oxide-semiconductor field-effect transistors (MOSFETs). Analytical surface potential models have been developed at front and back surfaces of the channel by solving the two-dimensional (2-D) Poisson's equation in the channel region with appropriate boundary conditions assuming a parabolic potential profile in the transverse direction of the channel. The strong inversion criterion is applied to the front surface potential as well as on the back one in order to find two separate threshold voltages for front and back channels of the device, respectively. The device threshold voltage has been assumed to be associated with the surface that offers a lower threshold voltage. The developed model was analyzed extensively for a variety of device geometry parameters like the oxide and silicon channel thicknesses, the thickness of the source/drain extension in the buried oxide, and the applied bias voltages with back-gate control. The proposed model has been validated by comparing the analytical results with numerical simulation data obtained from ATLAS™, a 2-D device simulator from SILVACO.

Mass separation of rare-earth elements by a high-temperature thermal ion source coupled with a He-jet system

International Nuclear Information System (INIS)

Kawase, Y.; Okano, K.; Aoki, K.

1987-01-01

By using a high-temperature thermal ion source coupled to a He-jet system, neutron-rich isotopes of rare-earth elements such as cerium, praseodymium, neodymium and promethium produced by the thermal-neutron fission of /sup 235/U were ionized and successfully separated. The temperature dependence of the ionization efficiency has been measured and found to be explained qualitatively by the vapour pressure of the relevant elements. The characteristic temperature dependence of the ionization efficiency has been utilized for Z-identification of several isobars of rare-earth elements. The heaviest isotopes of neodymium and promethium, /sup 155/Nd and /sup 156/Pm, have recently been identified

Operation manual for the INEL on-line mass-separator facility

International Nuclear Information System (INIS)

Anderl, R.A.

1984-06-01

This report is an operation manual for an on-line mass-separator facility which is located in Building 661 at the Test Reactor Area of the Idaho National Engineering Laboratory. The facility provides mass-separated sources of short-lived fission-product radionuclides whose decay properties can be studied using a variety of nuclear spectroscopic techniques. This facility is unique in that it utilizes the gas-jet technique to transport fission products from a 252 Cf source located in a hot cell to the ion source of the mass separator. This document includes the following: (a) a detailed description of the facility, (b) identification of equipment hazards and safety controls, (c) detailed operating procedures for startup, continuous operation and shutdown, (d) operating procedures for the californium hot cell, and (e) an operator's manual for the automated moving tape collector/data acquisition system. 7 references, 16 figures, 8 tables

Rule of thumb for binary isotope separations in a gas centrifuge

International Nuclear Information System (INIS)

Berger, M.H.

1985-12-01

A very simple hypothetical model of the binary isotope separation process in a countercurrent Gas Centrifuge is proposed. Like the usual Cohen-Onsager separation theory it involves the internal fluid dynamics, but unlike the usual isotopic separation theory it completely obviates the usual flow integrals for Cohen's E. Thereby allowing an immediate estimate of the flow efficiency of a given design, which can and sometimes should be checked later by the usual analyses. To shed some light on our idea, two simple derivations for assumed idealized hydrodynamics are given, but a rigorous proof remains an open question. Then our hypothesis is tested against a battery of about 10 new ''exact'' formulas for E based upon analytical solutions to several variants of Onsager's pancake equation and found to be ''reasonably'' accurate and surprisingly robust. Finally, some limitations of our rule are explored

Sensitivity of the Speech Intelligibility Index to the Assumed Dynamic Range

Science.gov (United States)

Jin, In-Ki; Kates, James M.; Arehart, Kathryn H.

2017-01-01

Purpose: This study aims to evaluate the sensitivity of the speech intelligibility index (SII) to the assumed speech dynamic range (DR) in different languages and with different types of stimuli. Method: Intelligibility prediction uses the absolute transfer function (ATF) to map the SII value to the predicted intelligibility for a given stimuli.…

The impact of assumed knowledge entry standards on undergraduate mathematics teaching in Australia

Science.gov (United States)

King, Deborah; Cattlin, Joann

2015-10-01

Over the last two decades, many Australian universities have relaxed their selection requirements for mathematics-dependent degrees, shifting from hard prerequisites to assumed knowledge standards which provide students with an indication of the prior learning that is expected. This has been regarded by some as a positive move, since students who may be returning to study, or who are changing career paths but do not have particular prerequisite study, now have more flexible pathways. However, there is mounting evidence to indicate that there are also significant negative impacts associated with assumed knowledge approaches, with large numbers of students enrolling in degrees without the stated assumed knowledge. For students, there are negative impacts on pass rates and retention rates and limitations to pathways within particular degrees. For institutions, the necessity to offer additional mathematics subjects at a lower level than normal and more support services for under-prepared students impacts on workloads and resources. In this paper, we discuss early research from the First Year in Maths project, which begins to shed light on the realities of a system that may in fact be too flexible.

Compositional Synthesis of Controllers from Scenario-Based Assume-Guarantee Specifications

DEFF Research Database (Denmark)

Greenyer, Joel; Kindler, Ekkart

2013-01-01

Modern software-intensive systems often consist of multiple components that interact to fulfill complex functions in sometimes safety-critical situations. During the design, it is crucial to specify the system's requirements formally and to detect inconsistencies as early as possible in order to ...... present, in this paper, a novel assume-guarantee-style compositional synthesis technique for MSD specifications. We provide evaluation results underlining the benefit of our approach and formally justify its correctness....

Assumed genetic effects of low level irradiation on man

International Nuclear Information System (INIS)

Dutrillaux, B.

1976-01-01

The significance of human genetic pathology is stated and a study is made of the assumed effect of low level ionizing radiations. The theoretical notions thus derived are compared to experimental data which are poor. A quick survey of the literature shows that is has not yet been possible to establish a direct relationship between an increase of exposure and any genetic effect on man. However, this must not lead to conclude on the innoxiousness of radiation but rather shows how such analyses are difficult in as much as the effect investigated is necessarily low [fr

Isotope separation system

International Nuclear Information System (INIS)

Lehmann, J.-C.

1975-01-01

A description is given of an isotope separation device comprising a system for converting into gaseous form a first and second isotope to be separated, a monochromatic excitation light source to excite the gaseous molecules of these two isotopes in a distinct manner, a first and second receiver to collect selectively the molecules of the first and second distinctly excited isotopes. The frequency FL of the excitation light is selected between a lower limit and a higher limit F2 + 1/2 LD, depending on the frequences F1 and F2 of two absorption lines near this first and second isotope. The difference DF between these two frequencies F1 and F2 is less than the Doppler width LD of each one of these lines and greater than the natural width LN of each of these two lines and also the width of line LR of the excitation light source. The probability that the molecules will be excited by this light depends on the direction of their displacement to a major and different extent for both isotopes. An ionising light source LI is set up to irradiate the seat of interaction between the excitation light and the gaseous molecules with an ionisation light able to ionise the excited molecules without ionising the molecules that are not excited. The receivers are able to collect selectively the ionised molecules. A sufficiently low gas pressure is selected for the distance between the place of interaction and the first receiver to be less than double the free mean travel of the molecules in the gas [fr

Separation of the Magnetic Field into External and Internal Parts

DEFF Research Database (Denmark)

Olsen, Nils; Glassmeier, K.-H.; Jia, X.

2010-01-01

The magnetic field of a planet or a planetary moon contains contributions from a variety of sources in the environment of the body (external sources) and its interior (internal sources). This chapter describes different methods that have been developed for the separation of external and internal...

Feature Selection and Blind Source Separation in an EEG-Based Brain-Computer Interface

Directory of Open Access Journals (Sweden)

Michael H. Thaut

2005-11-01

Full Text Available Most EEG-based BCI systems make use of well-studied patterns of brain activity. However, those systems involve tasks that indirectly map to simple binary commands such as “yes” or “no” or require many weeks of biofeedback training. We hypothesized that signal processing and machine learning methods can be used to discriminate EEG in a direct “yes”/“no” BCI from a single session. Blind source separation (BSS and spectral transformations of the EEG produced a 180-dimensional feature space. We used a modified genetic algorithm (GA wrapped around a support vector machine (SVM classifier to search the space of feature subsets. The GA-based search found feature subsets that outperform full feature sets and random feature subsets. Also, BSS transformations of the EEG outperformed the original time series, particularly in conjunction with a subset search of both spaces. The results suggest that BSS and feature selection can be used to improve the performance of even a “direct,” single-session BCI.

Characterisation of the biochemical methane potential (BMP) of individual material fractions in Danish source-separated organic household waste

DEFF Research Database (Denmark)

Naroznova, Irina; Møller, Jacob; Scheutz, Charlotte

2016-01-01

This study is dedicated to characterising the chemical composition and biochemical methane potential (BMP) of individual material fractions in untreated Danish source-separated organic household waste (SSOHW). First, data on SSOHW in different countries, available in the literature, were evaluated...... and then, secondly, laboratory analyses for eight organic material fractions comprising Danish SSOHW were conducted. No data were found in the literature that fully covered the objectives of the present study. Based on laboratory analyses, all fractions were assigned according to their specific properties......) and material degradability (BMP from laboratory incubation tests divided by TBMP) were expressed. Moreover, the degradability of lignocellulose biofibres (the share of volatile lignocellulose biofibre solids degraded in laboratory incubation tests) was calculated. Finally, BMP for average SSOHW composition...

Second law comparison of oxy-fuel combustion and post-combustion carbon dioxide separation

International Nuclear Information System (INIS)

Simpson, Adam P.; Simon, A.J.

2007-01-01

To define 2nd law efficiency targets for novel separation technologies, a simplified model of a power plant with two forms of CO 2 capture was developed. In this investigation, oxy-fuel combustion and post-combustion CO 2 separation were compared on an exergetic basis. Using exergy balances and black-box models of power plant components, multiple scenarios were run to determine the impact of plant configuration and separation unit efficiency on overall plant performance. Second law efficiency values from the literature were used to set the baseline performance of various CO 2 separation configurations. Assumed advances in 2nd law efficiency were used to determine the potential for overall system performance improvement. It was found that the 2nd law efficiency of air separation must reach a critical value before the thermodynamics of oxy-fuel combustion become favorable. Changes in operating equivalence ratio significantly move the tipping-point between post-combustion and oxy-fuel strategies

Errors resulting from assuming opaque Lambertian clouds in TOMS ozone retrieval

International Nuclear Information System (INIS)

Liu, X.; Newchurch, M.J.; Loughman, R.; Bhartia, P.K.

2004-01-01

Accurate remote sensing retrieval of atmospheric constituents over cloudy areas is very challenging because of insufficient knowledge of cloud parameters. Cloud treatments are highly idealized in most retrieval algorithms. Using a radiative transfer model treating clouds as scattering media, we investigate the effects of assuming opaque Lambertian clouds and employing a Partial Cloud Model (PCM) on Total Ozone Mapping Spectrometer (TOMS) ozone retrievals, especially for tropical high-reflectivity clouds. Assuming angularly independent cloud reflection is good because the Ozone Retrieval Errors (OREs) are within 1.5% of the total ozone (i.e., within TOMS retrieval precision) when Cloud Optical Depth (COD)≥20. Because of Intra-Cloud Ozone Absorption ENhancement (ICOAEN), assuming opaque clouds can introduce large OREs even for optically thick clouds. For a water cloud of COD 40 spanning 2-12 km with 20.8 Dobson Unit (DU) ozone homogeneously distributed in the cloud, the ORE is 17.8 DU in the nadir view. The ICOAEN effect depends greatly on solar zenith angle, view zenith angle, and intra-cloud ozone amount and distribution. The TOMS PCM is good because negative errors from the cloud fraction being underestimated partly cancel other positive errors. At COD≤5, the TOMS algorithm retrieves approximately the correct total ozone because of compensating errors. With increasing COD up to 20-40, the overall positive ORE increases and is finally dominated by the ICOAEN effect. The ICOAEN effect is typically 5-13 DU on average over the Atlantic and Africa and 1-7 DU over the Pacific for tropical high-altitude (cloud top pressure ≤300 hPa) and high-reflectivity (reflectivity ≥ 80%) clouds. Knowledge of TOMS ozone retrieval errors has important implications for remote sensing of ozone/trace gases from other satellite instruments

X-ray radiometric separation of low-grade tin ores

Energy Technology Data Exchange (ETDEWEB)

Kotler, N.I.; Neverov, A.D.; Konovalov, V.M.; Mironov, I.I.; Zakharov, S.N.

1984-10-01

The investigations on evaluation of X-ray radiometric separation of off-grade tin ores of one of the deposits are carried out. The experiments have been performed at loboratory and pilot-commerical plants. /sup 241/Am has been used as a radiation source. In the course of facility commercial the ore has been separated by means of a device comprising a separator and gate separatin device. The results of X-ray radiometric separation have shown its high productive efficiency. Concentrates with higher tin content at high extraction from ores are obtained.

X-ray radiometric separation of low-grade tin ores

International Nuclear Information System (INIS)

Kotler, N.I.; Neverov, A.D.; Konovalov, V.M.; Mironov, I.I.; Zakharov, S.N.

1984-01-01

The investigations on evaluation of X-ray radiometric separation of off-grade tin ores of one of the deposits are carried out. The experiments have been performed at loboratory and pilot-commerical plants. 241 Am has been used as a radiation source. In the course of facility commercial the ore has been separated by means of a device comprising a separator and gate separatin device. The results of X-ray radiometric separation have shown its high productive efficiency. Concentrates with higher tin content at high extraction from ores are obtained

X-ray source array

International Nuclear Information System (INIS)

Cooperstein, G.; Lanza, R.C.; Sohval, A.R.

1983-01-01

A circular array of cold cathode diode X-ray sources, for radiation imaging applications, such as computed tomography includes electrically conductive cathode plates each of which cooperates with at least two anodes to form at least two diode sources. In one arrangement, two annular cathodes are separated by radially extending, rod-like anodes. Field enhancement blades may be provided on the cathodes. In an alternative arrangement, the cathode plates extend radially and each pair is separated by an anode plate also extending radially. (author)

Land Streamer Surveying Using Multiple Sources

KAUST Repository

Mahmoud, Sherif

2014-12-11

Various examples are provided for land streamer seismic surveying using multiple sources. In one example, among others, a method includes disposing a land streamer in-line with first and second shot sources. The first shot source is at a first source location adjacent to a proximal end of the land streamer and the second shot source is at a second source location separated by a fixed length corresponding to a length of the land streamer. Shot gathers can be obtained when the shot sources are fired. In another example, a system includes a land streamer including a plurality of receivers, a first shot source located adjacent to the proximal end of the land streamer, and a second shot source located in-line with the land streamer and the first shot source. The second shot source is separated from the first shot source by a fixed overall length corresponding to the land streamer.

Cesium and Strontium Separation Technologies Literature Review

Energy Technology Data Exchange (ETDEWEB)

T. A. Todd; T. A. Todd; J. D. Law; R. S. Herbst

2004-03-01

Integral to the Advanced Fuel Cycle Initiative (AFCI) Program’s proposed closed nuclear fuel cycle, the fission products cesium and strontium in the dissolved spent nuclear fuel stream are to be separated and managed separately. A comprehensive literature survey is presented to identify cesium and strontium separation technologies that have the highest potential and to focus research and development efforts on these technologies. Removal of these high-heat-emitting fission products reduces the radiation fields in subsequent fuel cycle reprocessing streams and provides a significant short-term (100 yr) heat source reduction in the repository. This, along with separation of actinides, may provide a substantial future improvement in the amount of fuel that could be stored in a geologic repository. The survey and review of the candidate cesium and strontium separation technologies are presented herein. Because the AFCI program intends to manage cesium and strontium together, technologies that simultaneously separate both elements are of the greatest interest, relative to technologies that separate only one of the two elements.

Retrieving global aerosol sources from satellites using inverse modeling

Directory of Open Access Journals (Sweden)

O. Dubovik

2008-01-01

Full Text Available Understanding aerosol effects on global climate requires knowing the global distribution of tropospheric aerosols. By accounting for aerosol sources, transports, and removal processes, chemical transport models simulate the global aerosol distribution using archived meteorological fields. We develop an algorithm for retrieving global aerosol sources from satellite observations of aerosol distribution by inverting the GOCART aerosol transport model.

The inversion is based on a generalized, multi-term least-squares-type fitting, allowing flexible selection and refinement of a priori algorithm constraints. For example, limitations can be placed on retrieved quantity partial derivatives, to constrain global aerosol emission space and time variability in the results. Similarities and differences between commonly used inverse modeling and remote sensing techniques are analyzed. To retain the high space and time resolution of long-period, global observational records, the algorithm is expressed using adjoint operators.

Successful global aerosol emission retrievals at 2°×2.5 resolution were obtained by inverting GOCART aerosol transport model output, assuming constant emissions over the diurnal cycle, and neglecting aerosol compositional differences. In addition, fine and coarse mode aerosol emission sources were inverted separately from MODIS fine and coarse mode aerosol optical thickness data, respectively. These assumptions are justified, based on observational coverage and accuracy limitations, producing valuable aerosol source locations and emission strengths. From two weeks of daily MODIS observations during August 2000, the global placement of fine mode aerosol sources agreed with available independent knowledge, even though the inverse method did not use any a priori information about aerosol sources, and was initialized with a "zero aerosol emission" assumption. Retrieving coarse mode aerosol emissions was less successful

Advances in audio source seperation and multisource audio content retrieval

Science.gov (United States)

Vincent, Emmanuel

2012-06-01

Audio source separation aims to extract the signals of individual sound sources from a given recording. In this paper, we review three recent advances which improve the robustness of source separation in real-world challenging scenarios and enable its use for multisource content retrieval tasks, such as automatic speech recognition (ASR) or acoustic event detection (AED) in noisy environments. We present a Flexible Audio Source Separation Toolkit (FASST) and discuss its advantages compared to earlier approaches such as independent component analysis (ICA) and sparse component analysis (SCA). We explain how cues as diverse as harmonicity, spectral envelope, temporal fine structure or spatial location can be jointly exploited by this toolkit. We subsequently present the uncertainty decoding (UD) framework for the integration of audio source separation and audio content retrieval. We show how the uncertainty about the separated source signals can be accurately estimated and propagated to the features. Finally, we explain how this uncertainty can be efficiently exploited by a classifier, both at the training and the decoding stage. We illustrate the resulting performance improvements in terms of speech separation quality and speaker recognition accuracy.

Gradient method for blind chaotic signal separation based on proliferation exponent

International Nuclear Information System (INIS)

Lü Shan-Xiang; Wang Zhao-Shan; Hu Zhi-Hui; Feng Jiu-Chao

2014-01-01

A new method to perform blind separation of chaotic signals is articulated in this paper, which takes advantage of the underlying features in the phase space for identifying various chaotic sources. Without incorporating any prior information about the source equations, the proposed algorithm can not only separate the mixed signals in just a few iterations, but also outperforms the fast independent component analysis (FastICA) method when noise contamination is considerable. (general)

The Role of Separation Bubbles on the Aerodynamic Characteristics of Airfoils, Including Stall and Post-Stall, at Low Reynolds Numbers

Science.gov (United States)

Chen, Hsun H.; Cebeci, Tuncer

2007-01-01

Airfoils at high Reynolds numbers, in general, have small separation bubbles that are usually confined to the leading edge. Since the Reynolds number is large, the turbulence model for the transition region between the laminar and turbulent flow is not important. Furthermore, the onset of transition occurs either at separation or prior to separation and can be predicted satisfactorily by empirical correlations when the incident angle is small and can be assumed to correspond to laminar separation when the correlations do not apply, i.e., at high incidence angles.

Trace Pair Filtering for Separation of Upgoing and Downgoing Waves in Vsp (Vertical Seismic Profile) Filtrage à deux canaux pour la séparation des ondes montantes et descendantes en PSV (Profil Sismique Vertical)

OpenAIRE

Glangeaud F.; Durand P.; Mari J. L.; Coppens F.

2006-01-01

Most multichannel algorithms used for separation of upgoing and downgoing waves in VSPs assume depth-stationarity of the signal on all the traces used in the separation filter. However, if the depth-window of the filters becomes too large (100-200 m) signal stationarity cannot be assumed. On the other hand, stationarity is a physically reasonable assumption for two neighbouring probe locations (5-20 m). A comparison is made of three algorithms used for the separation of upgoing and downgoing ...

Prospects of Source-Separation-Based Sanitation Concepts: A Model-Based Study

NARCIS (Netherlands)

Tervahauta, T.H.; Trang Hoang,; Hernández, L.; Zeeman, G.; Buisman, C.J.N.

2013-01-01

Separation of different domestic wastewater streams and targeted on-site treatment for resource recovery has been recognized as one of the most promising sanitation concepts to re-establish the balance in carbon, nutrient and water cycles. In this study a model was developed based on literature data

Blind identification and separation of complex-valued signals

CERN Document Server

Moreau, Eric

2013-01-01

Blind identification consists of estimating a multi-dimensional system only through the use of its output, and source separation, the blind estimation of the inverse of the system. Estimation is generally carried out using different statistics of the output. The authors of this book consider the blind identification and source separation problem in the complex-domain, where the available statistical properties are richer and include non-circularity of the sources - underlying components. They define identifiability conditions and present state-of-the-art algorithms that are based on algebraic methods as well as iterative algorithms based on maximum likelihood theory. Contents 1. Mathematical Preliminaries. 2. Estimation by Joint Diagonalization. 3. Maximum Likelihood ICA. About the Authors Eric Moreau is Professor of Electrical Engineering at the University of Toulon, France. His research interests concern statistical signal processing, high order statistics and matrix/tensor decompositions with applic...

Method of deuterium isotope separation and enrichment

International Nuclear Information System (INIS)

Benson, S.W.

1979-01-01

A method is described for separating and enriching deuterium containing molecules comprising the steps of: providing a source of organic molecules containing a normal abundance of deuterium atoms, the organic molecules having a structural formula RX, in which R is an organic radical selected from ethyl, isopropyl, t-butyl and 3-cyclopentenyl, and in which X is selected from F, Cl, Br and OH, and wherein R represents 3-cyclopentenyl, X may additionally represent H; exposing the molecules to the radiation of at least one pulsed infrared laser source which has been specifically tuned and focussed to selectively decompose RX molecules containing deuterium to form an enriched olefin specie containing deuterium, and HX; and separating the deuterium enriched olefin specie from the undecomposed deuterium depleted RX molecules and HX. (author)

On line isotopic separator test benches at GANIL

International Nuclear Information System (INIS)

Anne, R.; Bru, B.; Joubert, A.; Leroy, R.; Obert, J.; Putaux, J.C.; Liang, C.F.; Paris, P.; Orr, N.; Steckmeyer, J.C.

1993-01-01

A first version of isotopic separator on line test bench has been built in order to test the feasibility of the production of radioactive species from 96 MeV/u of 20 Ne impinging a thick target of MgO. This test bench was equipped with a very compact ECR ion source (Nanogan) entirely made from permanent magnets and operating at 10 Ghz. 18 Ne 2,4+ ; 19N e 1,2,3,4+ and 23,24 Ne 1+ has been produced and ionized. A new more performing separator (SIRa) allowing the use of different types of ion sources will be completed by the end of 1993. (author) 4 refs., 4 figs., 1 tab

Source Segregation and Collection of Source-Segregated Waste

DEFF Research Database (Denmark)

Christensen, Thomas Højlund; Matsufuji, Y.

2011-01-01

of optimal handling of the waste. But in a few cases, the waste must also be separated at source, for example removing the protective plastic cover from a commercial advertisement received by mail, prior to putting the advertisement into the waste collection bin for recyclable paper. These issues are often...... in wastes segregation addressing: - Purpose of source segregation. - Segregation criteria and guidance. - Segregation potentials and efficiencies. - Systems for collecting segregated fraction....

Blind Source Separation Algorithms Using Hyperbolic and Givens Rotations for High-Order QAM Constellations

KAUST Repository

Shah, Syed Awais Wahab

2017-11-24

This paper addresses the problem of blind demixing of instantaneous mixtures in a multiple-input multiple-output communication system. The main objective is to present efficient blind source separation (BSS) algorithms dedicated to moderate or high-order QAM constellations. Four new iterative batch BSS algorithms are presented dealing with the multimodulus (MM) and alphabet matched (AM) criteria. For the optimization of these cost functions, iterative methods of Givens and hyperbolic rotations are used. A pre-whitening operation is also utilized to reduce the complexity of design problem. It is noticed that the designed algorithms using Givens rotations gives satisfactory performance only for large number of samples. However, for small number of samples, the algorithms designed by combining both Givens and hyperbolic rotations compensate for the ill-whitening that occurs in this case and thus improves the performance. Two algorithms dealing with the MM criterion are presented for moderate order QAM signals such as 16-QAM. The other two dealing with the AM criterion are presented for high-order QAM signals. These methods are finally compared with the state of art batch BSS algorithms in terms of signal-to-interference and noise ratio, symbol error rate and convergence rate. Simulation results show that the proposed methods outperform the contemporary batch BSS algorithms.

Insects associated with the composting process of solid urban waste separated at the source

Directory of Open Access Journals (Sweden)

Gladis Estela Morales

2010-01-01

Full Text Available Sarcosaprophagous macroinvertebrates (earthworms, termites and a number of Diptera larvae enhance changes in the physical and chemical properties of organic matter during degradation and stabilization processes in composting, causing a decrease in the molecular weights of compounds. This activity makes these organisms excellent recyclers of organic matter. This article evaluates the succession of insects associated with the decomposition of solid urban waste separated at the source. The study was carried out in the city of Medellin, Colombia. A total of 11,732 individuals were determined, belonging to the classes Insecta and Arachnida. Species of three orders of Insecta were identified, Diptera, Coleoptera and Hymenoptera. Diptera corresponding to 98.5% of the total, was the most abundant and diverse group, with 16 families (Calliphoridae, Drosophilidae, Psychodidae, Fanniidae, Muscidae, Milichiidae, Ulidiidae, Scatopsidae, Sepsidae, Sphaeroceridae, Heleomyzidae, Stratiomyidae, Syrphidae, Phoridae, Tephritidae and Curtonotidae followed by Coleoptera with five families (Carabidae, Staphylinidae, Ptiliidae, Hydrophilidae and Phalacaridae. Three stages were observed during the composting process, allowing species associated with each stage to be identified. Other species were also present throughout the whole process. In terms of number of species, Diptera was the most important group observed, particularly Ornidia obesa, considered a highly invasive species, and Hermetia illuscens, both reported as beneficial for decomposition of organic matter.

Blind Source Separation Algorithms Using Hyperbolic and Givens Rotations for High-Order QAM Constellations

KAUST Repository

Shah, Syed Awais Wahab; Abed-Meraim, Karim; Al-Naffouri, Tareq Y.

2017-01-01

This paper addresses the problem of blind demixing of instantaneous mixtures in a multiple-input multiple-output communication system. The main objective is to present efficient blind source separation (BSS) algorithms dedicated to moderate or high-order QAM constellations. Four new iterative batch BSS algorithms are presented dealing with the multimodulus (MM) and alphabet matched (AM) criteria. For the optimization of these cost functions, iterative methods of Givens and hyperbolic rotations are used. A pre-whitening operation is also utilized to reduce the complexity of design problem. It is noticed that the designed algorithms using Givens rotations gives satisfactory performance only for large number of samples. However, for small number of samples, the algorithms designed by combining both Givens and hyperbolic rotations compensate for the ill-whitening that occurs in this case and thus improves the performance. Two algorithms dealing with the MM criterion are presented for moderate order QAM signals such as 16-QAM. The other two dealing with the AM criterion are presented for high-order QAM signals. These methods are finally compared with the state of art batch BSS algorithms in terms of signal-to-interference and noise ratio, symbol error rate and convergence rate. Simulation results show that the proposed methods outperform the contemporary batch BSS algorithms.

2D accelerator design for SITEX negative ion source

International Nuclear Information System (INIS)

Whealton, J.H.; Raridon, R.J.; McGaffey, R.W.; McCollough, D.H.; Stirling, W.L.; Dagenhart, W.K.

1983-01-01

Solving the Poisson-Vlasov equations where the magnetic field, B, is assumed constant, we optimize the optical system of a SITEX negative ion source in infinite slot geometry. Algorithms designed to solve the above equations were modified to include the curved emitter boundary data appropriate to a negative ion source. Other configurations relevant to negative ion sources are examined

Separation of gas mixtures

International Nuclear Information System (INIS)

1981-01-01

Apparatus is described for the separation of a gaseous plasma mixture into components in some of which the original concentration of a specific ion has been greatly increased or decreased, comprising: a source for converting the gaseous mixture into a train of plasma packets; an open-ended vessel with a main section and at least one branch section, adapted to enclose along predetermined tracks the original plasma packets in the main section, and the separated plasma components in the branch sections; drive means for generating travelling magnetic waves along the predetermined tracks with the magnetic flux vector of the waves transverse to each of the tracks; and means for maintaining phase coherence between the plasma packets and the magnetic waves at a value needed for accelerating the components of the packets to different velocities and in such different directions that the plasma of each packet is divided into distinctly separate packets in some of which the original concentration of a specific ion has been greatly increased or decreased, and which plasma packets are collected from the branch sections of the vessels. (author)

Ultracentrifuge separative power modeling with multivariate regression using covariance matrix

International Nuclear Information System (INIS)

Migliavacca, Elder

2004-01-01

In this work, the least-squares methodology with covariance matrix is applied to determine a data curve fitting to obtain a performance function for the separative power δU of a ultracentrifuge as a function of variables that are experimentally controlled. The experimental data refer to 460 experiments on the ultracentrifugation process for uranium isotope separation. The experimental uncertainties related with these independent variables are considered in the calculation of the experimental separative power values, determining an experimental data input covariance matrix. The process variables, which significantly influence the δU values are chosen in order to give information on the ultracentrifuge behaviour when submitted to several levels of feed flow rate F, cut θ and product line pressure P p . After the model goodness-of-fit validation, a residual analysis is carried out to verify the assumed basis concerning its randomness and independence and mainly the existence of residual heteroscedasticity with any explained regression model variable. The surface curves are made relating the separative power with the control variables F, θ and P p to compare the fitted model with the experimental data and finally to calculate their optimized values. (author)

Cesium glass irradiation sources

International Nuclear Information System (INIS)

Plodinec, M.J.

1982-01-01

The precipitation process for the decontamination of soluble SRP wastes produces a material whose radioactivity is dominated by 137 Cs. Potentially, this material could be vitrified to produce irradiation sources similar to the Hanford CsCl sources. In this report, process steps necessary for the production of cesium glass irradiation sources (CGS), and the nature of the sources produced, are examined. Three options are considered in detail: direct vitrification of precipitation process waste; direct vitrification of this waste after organic destruction; and vitrification of cesium separated from the precipitation process waste. Direct vitrification is compatible with DWPF equipment, but process rates may be limited by high levels of combustible materials in the off-gas. Organic destruction would allow more rapid processing. In both cases, the source produced has a dose rate of 2 x 10 4 rads/hr at the surface. Cesium separation produces a source with a dose rate of 4 x 10 5 at the surface, which is nearer that of the Hanford sources (2 x 10 6 rads/hr). Additional processing steps would be required, as well as R and D to demonstrate that DWPF equipment is compatible with this intensely radioactive material

Fast temperature optimization of multi-source hyperthermia applicators with reduced-order modeling of 'virtual sources'

International Nuclear Information System (INIS)

Cheng, K-S; Stakhursky, Vadim; Craciunescu, Oana I; Stauffer, Paul; Dewhirst, Mark; Das, Shiva K

2008-01-01

The goal of this work is to build the foundation for facilitating real-time magnetic resonance image guided patient treatment for heating systems with a large number of physical sources (e.g. antennas). Achieving this goal requires knowledge of how the temperature distribution will be affected by changing each source individually, which requires time expenditure on the order of the square of the number of sources. To reduce computation time, we propose a model reduction approach that combines a smaller number of predefined source configurations (fewer than the number of actual sources) that are most likely to heat tumor. The source configurations consist of magnitude and phase source excitation values for each actual source and may be computed from a CT scan based plan or a simplified generic model of the corresponding patient anatomy. Each pre-calculated source configuration is considered a 'virtual source'. We assume that the actual best source settings can be represented effectively as weighted combinations of the virtual sources. In the context of optimization, each source configuration is treated equivalently to one physical source. This model reduction approach is tested on a patient upper-leg tumor model (with and without temperature-dependent perfusion), heated using a 140 MHz ten-antenna cylindrical mini-annular phased array. Numerical simulations demonstrate that using only a few pre-defined source configurations can achieve temperature distributions that are comparable to those from full optimizations using all physical sources. The method yields close to optimal temperature distributions when using source configurations determined from a simplified model of the tumor, even when tumor position is erroneously assumed to be ∼2.0 cm away from the actual position as often happens in practical clinical application of pre-treatment planning. The method also appears to be robust under conditions of changing, nonlinear, temperature-dependent perfusion. The

A Cabin Air Separator for EVA Oxygen

Science.gov (United States)

Graf, John C.

2011-01-01

Presently, the Extra-Vehicular Activities (EVAs) conducted from the Quest Joint Airlock on the International Space Station use high pressure, high purity oxygen that is delivered to the Space Station by the Space Shuttle. When the Space Shuttle retires, a new method of delivering high pressure, high purity oxygen to the High Pressure Gas Tanks (HPGTs) is needed. One method is to use a cabin air separator to sweep oxygen from the cabin air, generate a low pressure/high purity oxygen stream, and compress the oxygen with a multistage mechanical compressor. A main advantage to this type of system is that the existing low pressure oxygen supply infrastructure can be used as the source of cabin oxygen. ISS has two water electrolysis systems that deliver low pressure oxygen to the cabin, as well as chlorate candles and compressed gas tanks on cargo vehicles. Each of these systems can feed low pressure oxygen into the cabin, and any low pressure oxygen source can be used as an on-board source of oxygen. Three different oxygen separator systems were evaluated, and a two stage Pressure Swing Adsorption system was selected for reasons of technical maturity. Two different compressor designs were subjected to long term testing, and the compressor with better life performance and more favorable oxygen safety characteristics was selected. These technologies have been used as the basis of a design for a flight system located in Equipment Lock, and taken to Preliminary Design Review level of maturity. This paper describes the Cabin Air Separator for EVA Oxygen (CASEO) concept, describes the separator and compressor technology trades, highlights key technology risks, and describes the flight hardware concept as presented at Preliminary Design Review (PDR)

Investigation of natural phosphatidylcholine sources: separation and identification by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS2) of molecular species.

Science.gov (United States)

Le Grandois, Julie; Marchioni, Eric; Zhao, Minjie; Giuffrida, Francesca; Ennahar, Saïd; Bindler, Françoise

2009-07-22

This study is a contribution to the exploration of natural phospholipid (PL) sources rich in long-chain polyunsaturated fatty acids (LC-PUFAs) with nutritional interest. Phosphatidylcholines (PCs) were purified from total lipid extracts of different food matrices, and their molecular species were separated and identified by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS(2)). Fragmentation of lithiated adducts allowed for the identification of fatty acids linked to the glycerol backbone. Soy PC was particularly rich in species containing essential fatty acids, such as (18:2-18:2)PC (34.0%), (16:0-18:2)PC (20.8%), and (18:1-18:2)PC (16.3%). PC from animal sources (ox liver and egg yolk) contained major molecular species, such as (16:0-18:2)PC, (16:0-18:1)PC, (18:0-18:2)PC, or (18:0-18:1)PC. Finally, marine source (krill oil), which was particularly rich in (16:0-20:5)PC and (16:0-22:6)PC, appeared to be an interesting potential source for food supplementation with LC-PUFA-PLs, particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

A Model for Teacher Effects from Longitudinal Data without Assuming Vertical Scaling

Science.gov (United States)

Mariano, Louis T.; McCaffrey, Daniel F.; Lockwood, J. R.

2010-01-01

There is an increasing interest in using longitudinal measures of student achievement to estimate individual teacher effects. Current multivariate models assume each teacher has a single effect on student outcomes that persists undiminished to all future test administrations (complete persistence [CP]) or can diminish with time but remains…

Search for chemical separations of the element 106 homologues in HF and HF-HCl media

International Nuclear Information System (INIS)

Trubert, D.; Monroy-Guzman, F.; Hussonnois, M.; Brillard, L.; Le Naour, C.; Constantinescu, O.

1996-01-01

In order to study the chemical properties of element 263 106 in aqueous media, fast, efficient and reproducible chromatographic separations were tested on its assumed homologous: Mo, W and U. Corroborative static and dynamic off-line experiments have shown that after fixation of these three elements on anion-exchange resin in HF medium, selective elution could be achieved by using suitable concentration of HCl - HF and HCl solutions. Separations of short-lived W isotopes, produced through heavy ion irradiation were also performed on-line. (author). 27 refs., 14 figs

Impedance cardiography: What is the source of the signal?

Science.gov (United States)

Patterson, R. P.

2010-04-01

Impedance cardiography continues to be investigated for various applications. Instruments for its use are available commercially. Almost all of the recent presentations and articles along with commercial advertisements have assumed that aortic volume pulsation is the source of the signal. A review of the literature will reveal that there is no clear evidence for this assumption. Starting with the first paper on impedance cardiography in 1964, which assumed the lung was the source of the signal, the presentation will review many studies in the 60's, 70's and 80's, which suggest the aorta and other vessels as well as atria and again the lung as possible sources. Current studies based on high resolution thoracic models will be presented that show the aorta as contributing only approximately 1% of the total impedance measurement, making it an unlikely candidate for the major contributor to the signal. Combining the results of past studies along with recent work based on models, suggest other vessels and regions as possible sources.

Revision of the design model for a cryogenic falling liquid film helium separator

International Nuclear Information System (INIS)

Kinoshita, Masahiro; Bartlit, J.R.; Sherman, R.H.

1983-05-01

The present paper reports revision of the design model previously developed by the authors for the cryogenic falling liquid film helium separator. The revised design procedure is composed of three steps : 1) calculation of distributions of phase flow rates, temperature and phase compositions within the refrigerated section and the packed section ; 2) calculation of more detailed distributions of these variables within the refrigerated section ; and 3) estimation of column dimensions and determination of operating conditions. It is assumed that the vacant refrigerated section has two theoretical stages for hydrogen isotope separation. The mixture within the refrigerated section is considered in step 2) as two component system of He-HD. (author)

How Public High School Students Assume Cooperative Roles to Develop Their EFL Speaking Skills

Directory of Open Access Journals (Sweden)

Julie Natalie Parra Espinel

2010-12-01

Full Text Available This study describes an investigation we carried out in order to identify how the specific roles that 7th grade public school students assumed when they worked cooperatively were related to their development of speaking skills in English. Data were gathered through interviews, field notes, students’ reflections and audio recordings. The findings revealed that students who were involved in cooperative activities chose and assumed roles taking into account preferences, skills and personality traits. In the same manner, when learners worked together, their roles were affected by each other and they put into practice some social strategies with the purpose of supporting their embryonic speaking development.

Evaluation of a new pulping technology for pre-treating source-separated organic household waste prior to anaerobic digestion

DEFF Research Database (Denmark)

Naroznova, Irina; Møller, Jacob; Larsen, Bjarne

2016-01-01

A new technology for pre-treating source-separated organic household waste prior to anaerobic digestion was assessed, and its performance was compared to existing alternative pre-treatment technologies. This pre-treatment technology is based on waste pulping with water, using a specially developed...... screw mechanism. The pre-treatment technology rejects more than 95% (wet weight) of non-biodegradable impurities in waste collected from households and generates biopulp ready for anaerobic digestion. Overall, 84-99% of biodegradable material (on a dry weight basis) in the waste was recovered...... in the biopulp. The biochemical methane potential for the biopulp was 469±7mL CH4/g ash-free mass. Moreover, all Danish and European Union requirements regarding the content of hazardous substances in biomass intended for land application were fulfilled. Compared to other pre-treatment alternatives, the screw...

Blind Separation of Acoustic Signals Combining SIMO-Model-Based Independent Component Analysis and Binary Masking

Directory of Open Access Journals (Sweden)

Hiekata Takashi

2006-01-01

Full Text Available A new two-stage blind source separation (BSS method for convolutive mixtures of speech is proposed, in which a single-input multiple-output (SIMO-model-based independent component analysis (ICA and a new SIMO-model-based binary masking are combined. SIMO-model-based ICA enables us to separate the mixed signals, not into monaural source signals but into SIMO-model-based signals from independent sources in their original form at the microphones. Thus, the separated signals of SIMO-model-based ICA can maintain the spatial qualities of each sound source. Owing to this attractive property, our novel SIMO-model-based binary masking can be applied to efficiently remove the residual interference components after SIMO-model-based ICA. The experimental results reveal that the separation performance can be considerably improved by the proposed method compared with that achieved by conventional BSS methods. In addition, the real-time implementation of the proposed BSS is illustrated.

Microparticle Separation by Cyclonic Separation

Science.gov (United States)

Karback, Keegan; Leith, Alexander

2017-11-01

The ability to separate particles based on their size has wide ranging applications from the industrial to the medical. Currently, cyclonic separators are primarily used in agriculture and manufacturing to syphon out contaminates or products from an air supply. This has led us to believe that cyclonic separation has more applications than the agricultural and industrial. Using the OpenFoam computational package, we were able to determine the flow parameters of a vortex in a cyclonic separator in order to segregate dust particles to a cutoff size of tens of nanometers. To test the model, we constructed an experiment to separate a test dust of various sized particles. We filled a chamber with Arizona test dust and utilized an acoustic suspension technique to segregate particles finer than a coarse cutoff size and introduce them into the cyclonic separation apparatus where they were further separated via a vortex following our computational model. The size of the particles separated from this experiment will be used to further refine our model. Metropolitan State University of Denver, Colorado University of Denver, Dr. Randall Tagg, Dr. Richard Krantz.

Guide for the recovery of high grade waste paper from federal office buildings through at-source separation

Energy Technology Data Exchange (ETDEWEB)

1978-01-01

This guide is intended to serve as a manual for organizing and managing office waste paper recovery programs in Canadian federal buildings. Waste paper generated in such buildings is of particular interest for recycling as it is produced in sufficiently large amounts, and contains large amounts of high-grade waste paper which obtain good prices from paper mills. The key to successful recovery of such paper is separation, at the source of waste generation, from other less-valuable papers and non-paper materials. In recommending ways to do this, the manual covers assessment of the viability of a collection program in a particular building, estimating the quantities of waste generated, calculating storage space necessary, marketing the paper collected, using proper collection and storage containers, promoting employee awareness, and administering and monitoring the program. A sample cost-benefit analysis is given for a general office building with 1,000 employees. Includes glossary. 14 refs., 10 figs., 5 tabs.

Life cycle assessment for optimising the level of separated collection in integrated MSW management systems.

Science.gov (United States)

Rigamonti, L; Grosso, M; Giugliano, M

2009-02-01

This life cycle assessment study analyses material and energy recovery within integrated municipal solid waste (MSW) management systems, and, in particular, the recovery of the source-separated materials (packaging and organic waste) and the energy recovery from the residual waste. The recovery of materials and energy are analysed together, with the final aim to evaluate possible optimum levels of source-separated collection that lead to the most favourable energetic and environmental results; this method allows identification of an optimum configuration of the MSW management system. The results show that the optimum level of source-separated collection is about 60%, when all the materials are recovered with high efficiency; it decreases to about 50%, when the 60% level is reached as a result of a very high recovery efficiency for organic fractions at the expense of the packaging materials, or when this implies an appreciable reduction of the quality of collected materials. The optimum MSW management system is thus characterized by source-separated collection levels as included in the above indicated range, with subsequent recycling of the separated materials and energy recovery of the residual waste in a large-scale incinerator operating in combined heat and power mode.

Properties of neutron sources

International Nuclear Information System (INIS)

1987-03-01

The Conference presentations were divided into sessions devoted to the following topics: white neutron sources, primarily pulsed (6 papers); fast neutron fields (5 papers); Californium-252 prompt fission neutron spectra (14 papers); monoenergetic sources and filtered beams (11 papers); 14 MeV neutron sources (10 papers); selected special application (one paper); and a general interest session (4 papers). Individual abstracts were prepared separately for the papers

Examination of Conservatism in Ground-level Source Release Assumption when Performing Consequence Analysis

Energy Technology Data Exchange (ETDEWEB)

Kim, Sung-yeop; Lim, Ho-Gon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2015-10-15

One of these assumptions frequently assumed is the assumption of ground-level source release. The user manual of a consequence analysis software HotSpot is mentioning like below: 'If you cannot estimate or calculate the effective release height, the actual physical release height (height of the stack) or zero for ground-level release should be used. This will usually yield a conservative estimate, (i.e., larger radiation doses for all downwind receptors, etc).' This recommendation could be agreed in aspect of conservatism but quantitative examination of the effect of this assumption to the result of consequence analysis is necessary. The source terms of Fukushima Dai-ichi NPP accident have been estimated by several studies using inverse modeling and one of the biggest sources of the difference between the results of these studies was different effective source release height assumed by each studies. It supports the importance of the quantitative examination of the influence by release height. Sensitivity analysis of the effective release height of radioactive sources was performed and the influence to the total effective dose was quantitatively examined in this study. Above 20% difference is maintained even at longer distances, when we compare the dose between the result assuming ground-level release and the results assuming other effective plume height. It means that we cannot ignore the influence of ground-level source assumption to the latent cancer fatality estimations. In addition, the assumption of ground-level release fundamentally prevents detailed analysis including diffusion of plume from effective plume height to the ground even though the influence of it is relatively lower in longer distance. When we additionally consider the influence of surface roughness, situations could be more serious. The ground level dose could be highly over-estimated in short downwind distance at the NPP sites which have low surface roughness such as Barakah site in

Radiochemical determination and separation or total radium, 226Ra and 224Ra; Analisis Radioquimico de Radio total, Radio-226 y Radio-224

Energy Technology Data Exchange (ETDEWEB)

Suarez, J A; Gonzalez, J A; Pablo, M A. de

1987-07-01

Radiochemical purification and separation of radium has been carried out and the determination of total radium solubilized in aqueous samples has been studied assuming that all the alpha emitters of the sample have their origin in the 226Ra and elements of its desintegration chain. Also, the activities of 22Ra and 226 Ra have been evaluated separately doing a measurement after the chemical separation of the radium and another one 10 days after. (Author) 9 refs.

Process for separating nitrogen from methane using microchannel process technology

Science.gov (United States)

Tonkovich, Anna Lee [Marysville, OH; Qiu, Dongming [Dublin, OH; Dritz, Terence Andrew [Worthington, OH; Neagle, Paul [Westerville, OH; Litt, Robert Dwayne [Westerville, OH; Arora, Ravi [Dublin, OH; Lamont, Michael Jay [Hilliard, OH; Pagnotto, Kristina M [Cincinnati, OH

2007-07-31

The disclosed invention relates to a process for separating methane or nitrogen from a fluid mixture comprising methane and nitrogen, the process comprising: (A) flowing the fluid mixture into a microchannel separator, the microchannel separator comprising a plurality of process microchannels containing a sorption medium, the fluid mixture being maintained in the microchannel separator until at least part of the methane or nitrogen is sorbed by the sorption medium, and removing non-sorbed parts of the fluid mixture from the microchannel separator; and (B) desorbing the methane or nitrogen from the sorption medium and removing the desorbed methane or nitrogen from the microchannel separator. The process is suitable for upgrading methane from coal mines, landfills, and other sub-quality sources.

Enantiomeric Mixtures in Natural Product Chemistry: Separation and Absolute Configuration Assignment.

Science.gov (United States)

N L Batista, Andrea; M Dos Santos, Fernando; Batista, João M; Cass, Quezia B

2018-02-23

Chiral natural product molecules are generally assumed to be biosynthesized in an enantiomerically pure or enriched fashion. Nevertheless, a significant amount of racemates or enantiomerically enriched mixtures has been reported from natural sources. This number is estimated to be even larger since the enantiomeric purity of secondary metabolites is rarely checked in the natural product isolation pipeline. This latter fact may have drastic effects on the evaluation of the biological activity of chiral natural products. A second bottleneck is the determination of their absolute configurations. Despite the widespread use of optical rotation and electronic circular dichroism, most of the stereochemical assignments are based on empirical correlations with similar compounds reported in the literature. As an alternative, the combination of vibrational circular dichroism and quantum chemical calculations has emerged as a powerful and reliable tool for both conformational and configurational analysis of natural products, even for those lacking UV-Vis chromophores. In this review, we aim to provide the reader with a critical overview of the occurrence of enantiomeric mixtures of secondary metabolites in nature as well the best practices for their detection, enantioselective separation using liquid chromatography, and determination of absolute configuration by means of vibrational circular dichroism and density functional theory calculations.

HDR 192Ir source speed measurements using a high speed video camera

International Nuclear Information System (INIS)

Fonseca, Gabriel P.; Viana, Rodrigo S. S.; Yoriyaz, Hélio; Podesta, Mark; Rubo, Rodrigo A.; Sales, Camila P. de; Reniers, Brigitte; Verhaegen, Frank

2015-01-01

Purpose: The dose delivered with a HDR 192 Ir afterloader can be separated into a dwell component, and a transit component resulting from the source movement. The transit component is directly dependent on the source speed profile and it is the goal of this study to measure accurate source speed profiles. Methods: A high speed video camera was used to record the movement of a 192 Ir source (Nucletron, an Elekta company, Stockholm, Sweden) for interdwell distances of 0.25–5 cm with dwell times of 0.1, 1, and 2 s. Transit dose distributions were calculated using a Monte Carlo code simulating the source movement. Results: The source stops at each dwell position oscillating around the desired position for a duration up to (0.026 ± 0.005) s. The source speed profile shows variations between 0 and 81 cm/s with average speed of ∼33 cm/s for most of the interdwell distances. The source stops for up to (0.005 ± 0.001) s at nonprogrammed positions in between two programmed dwell positions. The dwell time correction applied by the manufacturer compensates the transit dose between the dwell positions leading to a maximum overdose of 41 mGy for the considered cases and assuming an air-kerma strength of 48 000 U. The transit dose component is not uniformly distributed leading to over and underdoses, which is within 1.4% for commonly prescribed doses (3–10 Gy). Conclusions: The source maintains its speed even for the short interdwell distances. Dose variations due to the transit dose component are much lower than the prescribed treatment doses for brachytherapy, although transit dose component should be evaluated individually for clinical cases

The Ability to Assume the Upright Position in Blind and Sighted Children.

Science.gov (United States)

Gipsman, Sandra Curtis

To investigate the ability of 48 blind and partially sighted children (8 to 10 and 12 to 14 years old) to assume the upright position, Ss were given six trials in which they were requested to move themselves from a tilted starting position in a specially constructed chair to an upright position. No significant differences were found between three…

Modeling the gas-particle partitioning of secondary organic aerosol: the importance of liquid-liquid phase separation

Directory of Open Access Journals (Sweden)

A. Zuend

2012-05-01

Full Text Available The partitioning of semivolatile organic compounds between the gas phase and aerosol particles is an important source of secondary organic aerosol (SOA. Gas-particle partitioning of organic and inorganic species is influenced by the physical state and water content of aerosols, and therefore ambient relative humidity (RH, as well as temperature and organic loading levels. We introduce a novel combination of the thermodynamic models AIOMFAC (for liquid mixture non-ideality and EVAPORATION (for pure compound vapor pressures with oxidation product information from the Master Chemical Mechanism (MCM for the computation of gas-particle partitioning of organic compounds and water. The presence and impact of a liquid-liquid phase separation in the condensed phase is calculated as a function of variations in relative humidity, organic loading levels, and associated changes in aerosol composition. We show that a complex system of water, ammonium sulfate, and SOA from the ozonolysis of α-pinene exhibits liquid-liquid phase separation over a wide range of relative humidities (simulated from 30% to 99% RH. Since fully coupled phase separation and gas-particle partitioning calculations are computationally expensive, several simplified model approaches are tested with regard to computational costs and accuracy of predictions compared to the benchmark calculation. It is shown that forcing a liquid one-phase aerosol with or without consideration of non-ideal mixing bears the potential for vastly incorrect partitioning predictions. Assuming an ideal mixture leads to substantial overestimation of the particulate organic mass, by more than 100% at RH values of 80% and by more than 200% at RH values of 95%. Moreover, the simplified one-phase cases stress two key points for accurate gas-particle partitioning calculations: (1 non-ideality in the condensed phase needs to be considered and (2 liquid-liquid phase separation is a consequence of considerable deviations

Method of deuterium isotope separation and enrichment

International Nuclear Information System (INIS)

Benson, S.W.

1978-01-01

A method of separating deuterium, i.e., heavy hydrogen, from certain naturally occurring sources using tuned infrared lasers to selectively decompose specified classes of organic molecules (i.e., RX) into enriched molecular products containing deuterium atoms is described. The deuterium containing molecules are easily separated from the starting material by absorption, distillation or other simple chemical separation techniques and methods. After evaporation such deuterium containing molecules can be burned to form water with an enriched deuterium content or pyrolyzed to form hydrogen gas with an enriched deuterium content. The undecomposed molecules and the other reaction products which are depleted of their deuterium containing species can be catalytically treated, preferably using normal water, to restore the natural abundance of deuterium and such restored molecules can then be recycled

Innovative lasers for uranium isotope separation

International Nuclear Information System (INIS)

Brake, M.L.; Gilgenbach, R.M.

1993-07-01

Copper vapor laser have important applications to uranium atomic vapor laser isotope separation (AVLIS). We have investigated two innovative methods of exciting/pumping copper vapor lasers which have the potential to improve the efficiency and scaling of large laser systems used in uranium isotope separation. Experimental research has focused on the laser discharge kinetics of (1) microwave, and (2) electron beam excitation/pumping of large-volume copper vapor lasers. Microwave resonant cavity produced copper vapor plasmas at 2.45 GHz, have been investigated in three separate experimental configurations. The first examined the application of CW (0-500W) power and was found to be an excellent method for producing an atomic copper vapor from copper chloride. The second used a pulsed (5kW, 0.5--5 kHz) signal superimposed on the CW signal to attempt to produce vaporization, dissociation and excitation to the laser states. Enhanced emission of the optical radiation was observed but power densities were found to be too low to achieve lasing. In a third experiment we attempted to increase the applied power by using a high power magnetron to produce 100 kW of pulsed power. Unfortunately, difficulties with the magnetron power supply were encountered leaving inconclusive results. Detailed modeling of the electromagnetics of the system were found to match the diagnostics results well. An electron beam pumped copper vapor system (350 kV, 1.0 kA, 300 ns) was investigated in three separate copper chloride heating systems, external chamber, externally heated chamber and an internally heated chamber. Since atomic copper spectral lines were not observed, it is assumed that a single pulse accelerator is not capable of both dissociating the copper chloride and exciting atomic copper and a repetitively pulsed electron beam generator is needed

Assumed Probability Density Functions for Shallow and Deep Convection

Directory of Open Access Journals (Sweden)

Steven K Krueger

2010-10-01

Full Text Available The assumed joint probability density function (PDF between vertical velocity and conserved temperature and total water scalars has been suggested to be a relatively computationally inexpensive and unified subgrid-scale (SGS parameterization for boundary layer clouds and turbulent moments. This paper analyzes the performance of five families of PDFs using large-eddy simulations of deep convection, shallow convection, and a transition from stratocumulus to trade wind cumulus. Three of the PDF families are based on the double Gaussian form and the remaining two are the single Gaussian and a Double Delta Function (analogous to a mass flux model. The assumed PDF method is tested for grid sizes as small as 0.4 km to as large as 204.8 km. In addition, studies are performed for PDF sensitivity to errors in the input moments and for how well the PDFs diagnose some higher-order moments. In general, the double Gaussian PDFs more accurately represent SGS cloud structure and turbulence moments in the boundary layer compared to the single Gaussian and Double Delta Function PDFs for the range of grid sizes tested. This is especially true for small SGS cloud fractions. While the most complex PDF, Lewellen-Yoh, better represents shallow convective cloud properties (cloud fraction and liquid water mixing ratio compared to the less complex Analytic Double Gaussian 1 PDF, there appears to be no advantage in implementing Lewellen-Yoh for deep convection. However, the Analytic Double Gaussian 1 PDF better represents the liquid water flux, is less sensitive to errors in the input moments, and diagnoses higher order moments more accurately. Between the Lewellen-Yoh and Analytic Double Gaussian 1 PDFs, it appears that neither family is distinctly better at representing cloudy layers. However, due to the reduced computational cost and fairly robust results, it appears that the Analytic Double Gaussian 1 PDF could be an ideal family for SGS cloud and turbulence

S.E.T., CSNI Separate Effects Test Facility Validation Matrix

International Nuclear Information System (INIS)

1997-01-01

1 - Description of test facility: The SET matrix of experiments is suitable for the developmental assessment of thermal-hydraulics transient system computer codes by selecting individual tests from selected facilities, relevant to each phenomena. Test facilities differ from one another in geometrical dimensions, geometrical configuration and operating capabilities or conditions. Correlation between SET facility and phenomena were calculated on the basis of suitability for model validation (which means that a facility is designed in such a way as to stimulate the phenomena assumed to occur in a plant and is sufficiently instrumented); limited suitability for model variation (which means that a facility is designed in such a way as to stimulate the phenomena assumed to occur in a plant but has problems associated with imperfect scaling, different test fluids or insufficient instrumentation); and unsuitability for model validation. 2 - Description of test: Whereas integral experiments are usually designed to follow the behaviour of a reactor system in various off-normal or accident transients, separate effects tests focus on the behaviour of a single component, or on the characteristics of one thermal-hydraulic phenomenon. The construction of a separate effects test matrix is an attempt to collect together the best sets of openly available test data for code validation, assessment and improvement, from the wide range of experiments that have been carried out world-wide in the field of thermal hydraulics. In all, 2094 tests are included in the SET matrix

Population studies of the unidentified EGRET sources

Energy Technology Data Exchange (ETDEWEB)

Siegal-Gaskins, J M [University of Chicago, Chicago, IL 60637 (United States); Pavlidou, V [University of Chicago, Chicago, IL 60637 (United States); Olinto, A V [University of Chicago, Chicago, IL 60637 (United States); Brown, C [University of Chicago, Chicago, IL 60637 (United States); Fields, B D [University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States)

2007-03-15

The third EGRET catalog contains a large number of unidentified sources. Current data allows the intriguing possibility that some of these objects may represent a new class of yet undiscovered gamma-ray sources. By assuming that galaxies similar to the Milky Way host comparable populations of objects, we constrain the allowed Galactic abundance and distribution of various classes of gamma-ray sources using the EGRET data set. Furthermore, regardless of the nature of the unidentified sources, faint unresolved objects of the same class contribute to the observed diffuse gamma-ray background. We investigate the potential contribution of these unresolved sources to the extragalactic gamma-ray background.

Population studies of the unidentified EGRET sources

International Nuclear Information System (INIS)

Siegal-Gaskins, J M; Pavlidou, V; Olinto, A V; Brown, C; Fields, B D

2007-01-01

The third EGRET catalog contains a large number of unidentified sources. Current data allows the intriguing possibility that some of these objects may represent a new class of yet undiscovered gamma-ray sources. By assuming that galaxies similar to the Milky Way host comparable populations of objects, we constrain the allowed Galactic abundance and distribution of various classes of gamma-ray sources using the EGRET data set. Furthermore, regardless of the nature of the unidentified sources, faint unresolved objects of the same class contribute to the observed diffuse gamma-ray background. We investigate the potential contribution of these unresolved sources to the extragalactic gamma-ray background

Separations Science Data Base: an abstractor's manual

International Nuclear Information System (INIS)

Roddy, J.W.; McDowell, W.J.; Michelson, D.C.

1981-07-01

The Separations Science Data Base, designed specifically for the retrieval of information needed in chemical separations problems (i.e., how to perform a given separation under given conditions), is described. The procedure for entering records into the data base is given. The initial entries are concerned primarily with liquid-liquid extraction and liquid-solid ion exchange methods for metal ions and salts; however, the data base is constructed so that almost any separations process can be accommodated. Each record is indexed with information provided under the following fields: author; title; publication source; date of publication; organization performing and/or sponsoring the work; brief abstract of the work; abstract number if the work has been so referenced, and/or abstractor's initials; type of separation system used (e.g., flotation); specific or generic name of the separation agent used (e.g., acetylacetone); list of substances separated (e.g., gold, copper); qualitative description of the supporting medium or matrix containing the substances before separation (e.g., nitrate); type of literature where the article was printed (e.g., book); and type of information that the article contains. Each of these fields may be searched independently of the others (or in combination), and the last six fields contain specific key words that are listed on the input form. Definitions are provided for the 39 information terms

Nonnegative Matrix Factor 2-D Deconvolution for Blind Single Channel Source Separation

DEFF Research Database (Denmark)

Schmidt, Mikkel N.; Mørup, Morten

2006-01-01

We present a novel method for blind separation of instruments in polyphonic music based on a non-negative matrix factor 2-D deconvolution algorithm. Using a model which is convolutive in both time and frequency we factorize a spectrogram representation of music into components corresponding...

Relativistic Inverse Scattering Problem for a Superposition of a Nonlocal Separable and a Local Quasipotential

International Nuclear Information System (INIS)

Chernichenko, Yu.D.

2005-01-01

Within the relativistic quasipotential approach to quantum field theory, the relativistic inverse scattering problem is solved for the case where the total quasipotential describing the interaction of two relativistic spinless particles having different masses is a superposition of a nonlocal separable and a local quasipotential. It is assumed that the local component of the total quasipotential is known and that there exist bound states in this local component. It is shown that the nonlocal separable component of the total interaction can be reconstructed provided that the local component, an increment of the phase shift, and the energies of bound states are known

Effects of the near field on source-independent q estimation

NARCIS (Netherlands)

Shigapov, R.; Kashtan, B.; Droujinine, A.; Mulder, W.A.

2013-01-01

We consider the problem of Q estimation from microseismic and from perforation shot data. Assuming that the source wavelet is not well known, we focused on the spectral ratio method and on source-independent viscoelastic full waveform inversion. We derived 3-D near-field approximations of monopole

Separation of hepatic iron and fat by dual-source dual-energy computed tomography based on material decomposition: an animal study.

Science.gov (United States)

Ma, Jing; Song, Zhi-Qiang; Yan, Fu-Hua

2014-01-01

To explore the feasibility of dual-source dual-energy computed tomography (DSDECT) for hepatic iron and fat separation in vivo. All of the procedures in this study were approved by the Research Animal Resource Center of Shanghai Ruijin Hospital. Sixty rats that underwent DECT scanning were divided into the normal group, fatty liver group, liver iron group, and coexisting liver iron and fat group, according to Prussian blue and HE staining. The data for each group were reconstructed and post-processed by an iron-specific, three-material decomposition algorithm. The iron enhancement value and the virtual non-iron contrast value, which indicated overloaded liver iron and residual liver tissue, respectively, were measured. Spearman's correlation and one-way analysis of variance (ANOVA) were performed, respectively, to analyze statistically the correlations with the histopathological results and differences among groups. The iron enhancement values were positively correlated with the iron pathology grading (r = 0.729, pVNC) values were negatively correlated with the fat pathology grading (r = -0.642,pVNC values (F = 25.308,pVNC values were only observed between the fat-present and fat-absent groups. Separation of hepatic iron and fat by dual energy material decomposition in vivo was feasible, even when they coexisted.

Jammer Suppression in DS-CDMA Communications using Parafac-based Blind Separation

Directory of Open Access Journals (Sweden)

Xu Lingyun

2016-01-01

Full Text Available In this paper we propose to apply parafac-based source separation techniques for jammer suppression in direct spread spectrum communication systems. The jammer excision is formulated as an optimization problem and a new algorithm is presented which is based on the parafac tri-iterative least square algorithm. By jointly diagonalizing the time delay correlation matrix of the observed signals and using the new proposed method, a better solution is achieved. The proposed algorithm can successfully separate communication signals and jamming signals. Simulation results reveal that our proposed algorithm has the better blind signal separation performance than joint diagonalization method. Our proposed algorithm doesn’t require whitening processing. Moreover our proposed algorithm works well in the underdetermined condition, where the number of sources exceeds than the number of antennas.

ON THE NEAR-INFRARED IDENTIFICATION OF THE INTEGRAL SOURCE IGR J16328–4726

Energy Technology Data Exchange (ETDEWEB)

Persi, P.; Fiocchi, M.; Bazzano, A.; Ubertini, P.; Parisi, P. [INAF/IAPS-Roma, Via fosso del cavaliere, 100, I-00133 Roma (Italy); Tapia, M. [Instituto de Astronomía, Universidad Nacional Autónoma de México, Ensenada, B.C. (Mexico); Roth, M., E-mail: paolo.persi@iaps.inaf.it [Las Campanas Observatory, Carnegie Institution of Washington, La Serena (Chile)

2015-07-15

The aim of this work is to identify the infrared (IR) counterpart of the Galactic high-mass X-ray binary IGR J16328–4726 discovered by the INTEGRAL satellite, and to derive the extinction and distance to the system. We present new deep sub-arcsecond JHK{sub s} imaging and low-resolution near-IR spectroscopy in the 1.5 and 2.4 μm range of IGR J16328–4726. We report the presence of two near-IR stellar sources separated by about 1.″8 at the location of the unresolved 2MASS source J16323791–4723409, previously considered to be the near-IR counterpart of the X-ray source. From the analysis of their near-IR colors and spectra as well as accurate positions, we uniquely identify the true IR counterpart of IGR J16328–4726. Our 1.5–2.4 μm spectrum of this star is consistent with the published classification O8Iafpe. Assuming this, and in combination with new JHK{sub s} photometry, a reddening A{sub V} = 23.6 ± 0.7 and a distance of 7.2 ± 0.3 kpc from the Sun are derived.

Method for separating gaseous mixtures of matter

International Nuclear Information System (INIS)

Schuster, E.; Kersting, A.

1979-01-01

Molecules to be separated from a mixture of matter of a chemical component are excited in a manner known per se by narrow-band light sources, and a chemical reaction partner for reacting with these molecules is admixed while supplied with energy by electromagnetic radiation or heating, and as additionally required for making chemical reactions possible. A method is described for separating gaseous mixtures of matter by exciting the molecules to be separated with laser radiation and causing the excited species to react chemically with a reaction partner. It may be necessary to supply additional energy to the reaction partner to make the chemical reaction possible. The method is applicable to the separation of hydrogen isotopes by the bromination of normal methanol in a mixture normal methanol and deuterated methanol; of uranium isotope by the reactions of UF 6 with SF 4 , SiCl 4 , HCl, or SO 2 ; and of boron isotopes by the reaction of BH 3 with NH 3

Asymmetric Joint Source-Channel Coding for Correlated Sources with Blind HMM Estimation at the Receiver

Directory of Open Access Journals (Sweden)

Ser Javier Del

2005-01-01

Full Text Available We consider the case of two correlated sources, and . The correlation between them has memory, and it is modelled by a hidden Markov chain. The paper studies the problem of reliable communication of the information sent by the source over an additive white Gaussian noise (AWGN channel when the output of the other source is available as side information at the receiver. We assume that the receiver has no a priori knowledge of the correlation statistics between the sources. In particular, we propose the use of a turbo code for joint source-channel coding of the source . The joint decoder uses an iterative scheme where the unknown parameters of the correlation model are estimated jointly within the decoding process. It is shown that reliable communication is possible at signal-to-noise ratios close to the theoretical limits set by the combination of Shannon and Slepian-Wolf theorems.

ALMA observations of lensed Herschel sources: testing the dark matter halo paradigm

Science.gov (United States)

Amvrosiadis, A.; Eales, S. A.; Negrello, M.; Marchetti, L.; Smith, M. W. L.; Bourne, N.; Clements, D. L.; De Zotti, G.; Dunne, L.; Dye, S.; Furlanetto, C.; Ivison, R. J.; Maddox, S. J.; Valiante, E.; Baes, M.; Baker, A. J.; Cooray, A.; Crawford, S. M.; Frayer, D.; Harris, A.; Michałowski, M. J.; Nayyeri, H.; Oliver, S.; Riechers, D. A.; Serjeant, S.; Vaccari, M.

2018-04-01

With the advent of wide-area submillimetre surveys, a large number of high-redshift gravitationally lensed dusty star-forming galaxies have been revealed. Because of the simplicity of the selection criteria for candidate lensed sources in such surveys, identified as those with S500 μm > 100 mJy, uncertainties associated with the modelling of the selection function are expunged. The combination of these attributes makes submillimetre surveys ideal for the study of strong lens statistics. We carried out a pilot study of the lensing statistics of submillimetre-selected sources by making observations with the Atacama Large Millimeter Array (ALMA) of a sample of strongly lensed sources selected from surveys carried out with the Herschel Space Observatory. We attempted to reproduce the distribution of image separations for the lensed sources using a halo mass function taken from a numerical simulation that contains both dark matter and baryons. We used three different density distributions, one based on analytical fits to the haloes formed in the EAGLE simulation and two density distributions [Singular Isothermal Sphere (SIS) and SISSA] that have been used before in lensing studies. We found that we could reproduce the observed distribution with all three density distributions, as long as we imposed an upper mass transition of ˜1013 M⊙ for the SIS and SISSA models, above which we assumed that the density distribution could be represented by a Navarro-Frenk-White profile. We show that we would need a sample of ˜500 lensed sources to distinguish between the density distributions, which is practical given the predicted number of lensed sources in the Herschel surveys.

THE DYNAMIC EVOLUTION OF YOUNG EXTRAGALACTIC RADIO SOURCES

International Nuclear Information System (INIS)

An Tao; Baan, Willem A.

2012-01-01

The evolution of symmetric extragalactic radio sources can be characterized by four distinct growth stages of the radio luminosity versus size of the source. The interaction of the jet with the ambient medium results in the formation and evolution of sources with non-standard (flaring) morphology. In addition, cessation or restarting of the jet power and obstruction of the jet will also result in distinct morphological structures. The radio source population may thus be classified in morphological types that indicate the prevailing physical processes. Compact symmetric objects (CSOs) occupy the earliest evolutionary phase of symmetric radio sources and their dynamical behavior is fundamental for any further evolution. Analysis of CSO dynamics is presented for a sample of 24 CSOs with known redshift and hotspot separation velocity and with a large range of radio power. Observables such as radio power, separation between two hotspots, hotspot separation velocity, and kinematic age of the source are found to be generally consistent with the self-similar predictions for individual sources that reflect the varying density structure of the ambient interstellar medium. Individual sources behave different from the group as a whole. The age and size statistics confirm that a large fraction of CSOs does not evolve into extended doubles.

THE DYNAMIC EVOLUTION OF YOUNG EXTRAGALACTIC RADIO SOURCES

Energy Technology Data Exchange (ETDEWEB)

An Tao [Shanghai Astronomical Observatory, Chinese Academy of Sciences, 200030 Shanghai (China); Baan, Willem A., E-mail: antao@shao.ac.cn, E-mail: baan@astron.nl [ASTRON, P.O. Box 2, 7990-AA Dwingeloo (Netherlands)

2012-11-20

The evolution of symmetric extragalactic radio sources can be characterized by four distinct growth stages of the radio luminosity versus size of the source. The interaction of the jet with the ambient medium results in the formation and evolution of sources with non-standard (flaring) morphology. In addition, cessation or restarting of the jet power and obstruction of the jet will also result in distinct morphological structures. The radio source population may thus be classified in morphological types that indicate the prevailing physical processes. Compact symmetric objects (CSOs) occupy the earliest evolutionary phase of symmetric radio sources and their dynamical behavior is fundamental for any further evolution. Analysis of CSO dynamics is presented for a sample of 24 CSOs with known redshift and hotspot separation velocity and with a large range of radio power. Observables such as radio power, separation between two hotspots, hotspot separation velocity, and kinematic age of the source are found to be generally consistent with the self-similar predictions for individual sources that reflect the varying density structure of the ambient interstellar medium. Individual sources behave different from the group as a whole. The age and size statistics confirm that a large fraction of CSOs does not evolve into extended doubles.

Application of fluidization to separate packaging waste plastics.

Science.gov (United States)

Carvalho, M Teresa; Ferreira, Célia; Portela, Antía; Santos, João Tiago

2009-03-01

The objective of the experimental work described in this paper is the study of the separation of PS (polystyrene) from PET (polyethylene terephthalate) and PVC (polyvinyl chloride) from drop-off points using a fluidized bed separator. This is a low-cost process commonly used in the hydro-classification of mineral ores. Firstly, experimental tests were carried out with artificial granulated samples with different grain sizes, types and sources of plastic ("separability tests"). The particle settling velocities were determined under different operating conditions. Then, based on the results, the laboratory tests continued with real mixtures of waste plastics ("separation tests") and the efficiency of the process was evaluated. From a PET-rich mixture, a concentrate of PS with a 75% grade in PS was produced while the underflow was quite clear from PS (grade less than 0.5% in PS).

Principles behind a He-jet system and its application for isotope separation

International Nuclear Information System (INIS)

Wollnik, H.

1976-01-01

The functioning of a He-jet transport system in explained paying special attention to the use of aerosols. Three applications of such a He-jet for an isotope separation are discussed: the use behind a recoil fission product separator, the transportation of activity into the ion source of a conventional mass separator, and the transportation into an α- or β-recoil time-of-flight spectrometer. (Auth.)

Separation of palladium from high-level waste using metal ferro cyanide loaded resins

International Nuclear Information System (INIS)

Valsala, T.P.; Joseph, Annie; Yeotikar, R.G.

2005-01-01

High-level waste (HLW) is generated during reprocessing of spent fuel. HLW contains corrosion products, unextracted actinides, process chemicals and fission products. A recent trend is there to consider waste as a source of wealth. Among the fission products separation and recovery of platinum group metals have gained great attention. HLW is a good source of palladium of the platinum group metal. The present study shows the feasibility of ion exchange separation of Pd from HLW. (author)

Dual-Source Swept-Source Optical Coherence Tomography Reconstructed on Integrated Spectrum

Directory of Open Access Journals (Sweden)

Shoude Chang

2012-01-01

Full Text Available Dual-source swept-source optical coherence tomography (DS-SSOCT has two individual sources with different central wavelengths, linewidth, and bandwidths. Because of the difference between the two sources, the individually reconstructed tomograms from each source have different aspect ratio, which makes the comparison and integration difficult. We report a method to merge two sets of DS-SSOCT raw data in a common spectrum, on which both data have the same spectrum density and a correct separation. The reconstructed tomographic image can seamlessly integrate the two bands of OCT data together. The final image has higher axial resolution and richer spectroscopic information than any of the individually reconstructed tomography image.

Surface ionization ion source with high current

International Nuclear Information System (INIS)

Fang Jinqing; Lin Zhizhou; Yu Lihua; Zhan Rongan; Huang Guojun; Wu Jianhua

1986-04-01

The working principle and structure of a surface ionization ion source with high current is described systematically. Some technological keypoints of the ion source are given in more detail, mainly including: choosing and shaping of the material of the surface ionizer, heating of the ionizer, distributing of working vapour on the ionizer surface, the flow control, the cooling problem at the non-ionization surface and the ion optics, etc. This ion source has been used since 1972 in the electromagnetic isotope separator with 180 deg angle. It is suitable for separating isotopes of alkali metals and rare earth metals. For instance, in the case of separating Rubidium, the maximum ion current of Rbsup(+) extracted from the ion source is about 120 mA, the maximum ion current accepted by the receiver is about 66 mA, the average ion current is more than 25 mA. The results show that our ion source have advantages of high ion current, good characteristics of focusing ion beam, working stability and structure reliability etc. It may be extended to other fields. Finally, some interesting phenomena in the experiment are disccused briefly. Some problems which should be investigated are further pointed out

Isotope separation by ionic cyclotron resonance

International Nuclear Information System (INIS)

Compant La Fontaine, A.; Gil, C.; Louvet, P.

1986-10-01

The principle of the process of isotopic separation by ionic cyclotron resonance is explained succinctly. The theoretical calculation of the isotopic effect is given as functions of the electric and magnetic fields in the frame of single particle approximation and of plasma collective theory. Then, the main parts of the demonstration device which is in operation at the CEA, are described here: the supraconducting magnetic field, the used diagnostics, the principle of the source and the collecting apparatus. Some experimental results are given for chromium. The application of the process to ponderal separation of metal isotopes, as chromium, nickel and molybdenum is discussed in view of production of medical, structural and irradiation isotopes

Elastic-plastic and creep analyses by assumed stress finite elements

International Nuclear Information System (INIS)

Pian, T.H.H.; Spilker, R.L.; Lee, S.W.

1975-01-01

A formulation is presented of incremental finite element solutions for both initial stress and initial strain problems based on modified complementary energy principle with relaxed inter-element continuity requirement. The corresponding finite element model is the assumed stress hybrid model which has stress parameters in the interior of each element and displacements at the individual nodes as unknowns. The formulation includes an important consideration that the states of stress and strain and the beginning of each increment may not satisfy the equilibrium and compatibility equations. These imbalance and mismatch conditions all lead to correction terms for the equivalent nodal forces of the matrix equations. The initial stress method is applied to elastic-plastic analysis of structures. In this case the stress parameters for the individual elements can be eliminated resulting to a system of equations with only nodal displacements as unknowns. Two different complementary energy principles can be formulated, in one of which the equilibrium of the final state of stress is maintained while in the other the equilibrium of the stress increments is maintained. Each of these two different formulations can be combined with different iterative schemes to be used at each incremental steps of the elastic-plastic analysis. It is also indicated clearly that for the initial stress method the state of stress at the beginning of each increments is in general, not in equilibrium and an imbalance correction is needed. Results of a comprehensive evaluation of various solution procedures by the initial stress method using the assumed stress hybrid elements are presented. The example used is the static response of a thick wall cylinder of elastic-perfectly plastic material under internal pressure. Solid of revolution elements with rectangular cross sections are used

Sound field separation with sound pressure and particle velocity measurements

DEFF Research Database (Denmark)

Fernandez Grande, Efren; Jacobsen, Finn; Leclère, Quentin

2012-01-01

separation techniques make it possible to distinguish between outgoing and incoming waves from the two sides, and thus NAH can be applied. In this paper, a separation method based on the measurement of the particle velocity in two layers and another method based on the measurement of the pressure...... and the velocity in a single layer are proposed. The two methods use an equivalent source formulation with separate transfer matrices for the outgoing and incoming waves, so that the sound from the two sides of the array can be modeled independently. A weighting scheme is proposed to account for the distance......In conventional near-field acoustic holography (NAH) it is not possible to distinguish between sound from the two sides of the array, thus, it is a requirement that all the sources are confined to only one side and radiate into a free field. When this requirement cannot be fulfilled, sound field...

Acoustic Holography With Incoherent Sources

NARCIS (Netherlands)

Druyvesteyn, W.F.; Raangs, R.

2005-01-01

In near field acoustic holography the sound field is scanned near the surface of the vibrating object; from these measurements the vibration of the structure can be calculated. In the case of correlated sources one reference signal is sufficient. When incoherent sources are present the separation of

Uranium age determination - Separation and analysis of 230Th and 231Pa

International Nuclear Information System (INIS)

Morgenstern, A.; Apostolidis, C.; Mayer, K.; Wallenius, M.

2002-01-01

Full text: In recent years several incidents involving illicit trafficking and smuggling of nuclear material, radioactive sources and radioactively contaminated materials have raised growing public concern about criminal acts involving nuclear materials. Consequently, research efforts in nuclear forensic science have been intensified in order to develop and improve methods for the identification of the nature and origin of seized materials. Information obtained from the analysis of unknown nuclear materials is of key importance in order to aide authorities that are in charge of developing fast and appropriate response action. For the identification of nuclear materials various sample characteristics are of relevance, including isotopic composition, the content of chemical impurities, material properties and the date of production. Information on the production date, respectively the 'age' of nuclear materials, will also be of key importance in other fields of nuclear science, i.e. for the verification of a Fissile Materials Cut-Off Treaty (FMCT) in order to distinguish freshly produced materials from 'old' excess weapons materials. The age of nuclear materials may also be of relevance under a strengthened safeguards regime to reveal clandestine production of weapons usable materials, i.e. the separation of plutonium or production of highly enriched uranium (HEU). The age dating of plutonium samples has been described in detail for bulk samples as well as for particles. In this work we focused on the age determination of uranium materials of different uranium enrichment. The radioactive decay of the uranium isotopes provides a chronometer that is inherent to the material, in particular the mother/daughter pairs 234 U/ 230 Th and 235 U/ 231 Pa can be advantageously used. Due to the relatively long half-lives of 234 U (2.46·10 5 years) and 235 U (7.04·10 8 years) only minute amounts of daughter nuclides are growing in, therefore both separation of Th and Pa from

Lupine protein enrichment by milling and electrostatic separation

NARCIS (Netherlands)

Wang, Jue; Zhao, Jun; Wit, De Martin; Boom, Remko M.; Schutyser, Maarten A.I.

2016-01-01

Lupine seeds are excellent source of plant protein. We here report on dry fractionation by combining milling and electrostatic separation providing an alternative to wet extraction of protein from lupine seeds. Relatively coarse milling was preferred as this provides sufficient detached protein

Testing earthquake source inversion methodologies

KAUST Repository

Page, Morgan T.

2011-01-01

Source Inversion Validation Workshop; Palm Springs, California, 11-12 September 2010; Nowadays earthquake source inversions are routinely performed after large earthquakes and represent a key connection between recorded seismic and geodetic data and the complex rupture process at depth. The resulting earthquake source models quantify the spatiotemporal evolution of ruptures. They are also used to provide a rapid assessment of the severity of an earthquake and to estimate losses. However, because of uncertainties in the data, assumed fault geometry and velocity structure, and chosen rupture parameterization, it is not clear which features of these source models are robust. Improved understanding of the uncertainty and reliability of earthquake source inversions will allow the scientific community to use the robust features of kinematic inversions to more thoroughly investigate the complexity of the rupture process and to better constrain other earthquakerelated computations, such as ground motion simulations and static stress change calculations.

Quasistatic modelling of the coaxial slow source

International Nuclear Information System (INIS)

Hahn, K.D.; Pietrzyk, Z.A.; Vlases, G.C.

1986-01-01

A new 1-D Lagrangian MHD numerical code in flux coordinates has been developed for the Coaxial Slow Source (CSS) geometry. It utilizes the quasistatic approximation so that the plasma evolves as a succession of equilibria. The P=P (psi) equilibrium constraint, along with the assumption of infinitely fast axial temperature relaxation on closed field lines, is incorporated. An axially elongated, rectangular plasma is assumed. The axial length is adjusted by the global average condition, or assumed to be fixed. In this paper predictions obtained with the code, and a limited amount of comparison with experimental data are presented

Electromagnetic separator for light and middle isotope elements

International Nuclear Information System (INIS)

Bernas, R.

1952-01-01

We describe a separator of isotope with a 60 deg magnetic sector that permits, thanks to a process of neutralization of the space charge, to use efficiently intense ion beams. The ion source for solid is essentially constituted by a discharge of hot cathode in a magnetic field and provides an ion beam focused of more than 10 mA. The result of the first separations (Zn, Sb, Hg) indicates that the isotopes of various elements can be obtained in quantities varying from 10 to 100 mg/24 hours. (author) [fr

Magnetogasdynamics of double radio sources

International Nuclear Information System (INIS)

Nepveu, M.

1979-01-01

The magnetogasdynamical behaviour of plasmoids moving through an ambient gas is investigated numerically with a two-dimensional code, based on the SHASTA scheme. The astrophysical importance of this study lies in the observed extended extragalactic radio sources. It is assumed that plasma clouds with cylinder symmetry are ejected from the nucleus of a galaxy. Their large-scale evolution in the intergalactic medium (IGM) is followed. The gas dynamics of an ejected cloud, the magnetogasdynamics of ejected clouds, the Christiansen-Pacholczyk-Scott picture for radio galaxies and the shear layers in double radio sources are studied. (Auth.)

Solution to the inversely stated transient source-receptor problem

International Nuclear Information System (INIS)

Sajo, E.; Sheff, J.R.

1995-01-01

Transient source-receptor problems are traditionally handled via the Boltzmann equation or through one of its variants. In the atmospheric transport of pollutants, meteorological uncertainties in the planetary boundary layer render only a few approximations to the Boltzmann equation useful. Often, due to the high number of unknowns, the atmospheric source-receptor problem is ill-posed. Moreover, models to estimate downwind concentration invariably assume that the source term is known. In this paper, an inverse methodology is developed, based on downwind measurement of concentration and that of meterological parameters to estimate the source term

Data analysis and source modelling for LISA

International Nuclear Information System (INIS)

Shang, Yu

2014-01-01

The gravitational waves are one of the most important predictions in general relativity. Besides of the directly proof of the existence of GWs, there are already several ground based detectors (such as LIGO, GEO, etc) and the planed future space mission (such as: LISA) which are aim to detect the GWs directly. GW contain a large amount of information of its source, extracting these information can help us dig out the physical property of the source, even open a new window for understanding the Universe. Hence, GW data analysis will be a challenging task in seeking the GWs. In this thesis, I present two works about the data analysis for LISA. In the first work, we introduce an extended multimodal genetic algorithm which utilizes the properties of the signal and the detector response function to analyze the data from the third round of mock LISA data challenge. We have found all five sources present in the data and recovered the coalescence time, chirp mass, mass ratio and sky location with reasonable accuracy. As for the orbital angular momentum and two spins of the Black Holes, we have found a large number of widely separated modes in the parameter space with similar maximum likelihood values. The performance of this method is comparable, if not better, to already existing algorithms. In the second work, we introduce an new phenomenological waveform model for the extreme mass ratio inspiral system. This waveform consists of a set of harmonics with constant amplitude and slowly evolving phase which we decompose in a Taylor series. We use these phenomenological templates to detect the signal in the simulated data, and then, assuming a particular EMRI model, estimate the physical parameters of the binary with high precision. The results show that our phenomenological waveform is very feasible in the data analysis of EMRI signal.

Effect of heterogeneity and assumed mode of inheritance on lod scores.

Science.gov (United States)

Durner, M; Greenberg, D A

1992-02-01

Heterogeneity is a major factor in many common, complex diseases and can confound linkage analysis. Using computer-simulated heterogeneous data we tested what effect unlinked families have on a linkage analysis when heterogeneity is not taken into account. We created 60 data sets of 40 nuclear families each with different proportions of linked and unlinked families and with different modes of inheritance. The ascertainment probability was 0.05, the disease had a penetrance of 0.6, and the recombination fraction for the linked families was zero. For the analysis we used a variety of assumed modes of inheritance and penetrances. Under these conditions we looked at the effect of the unlinked families on the lod score, the evaluation of the mode of inheritance, and the estimate of penetrance and of the recombination fraction in the linked families. 1. When the analysis was done under the correct mode of inheritance for the linked families, we found that the mode of inheritance of the unlinked families had minimal influence on the highest maximum lod score (MMLS) (i.e., we maximized the maximum lod score with respect to penetrance). Adding sporadic families decreased the MMLS less than adding recessive or dominant unlinked families. 2. The mixtures of dominant linked families with unlinked families always led to a higher MMLS when analyzed under the correct (dominant) mode of inheritance than when analyzed under the incorrect mode of inheritance. In the mixtures with recessive linked families, assuming the correct mode of inheritance generally led to a higher MMLS, but we observed broad variation.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of CO2 Separation from Flue Gas, Pipeline Transportation, and Sequestration in Coal

Energy Technology Data Exchange (ETDEWEB)

Eric P. Robertson

2007-09-01

This report was written to satisfy a milestone of the Enhanced Coal Bed Methane Recovery and CO2 Sequestration task of the Big Sky Carbon Sequestration project. The report begins to assess the costs associated with separating the CO2 from flue gas and then injecting it into an unminable coal seam. The technical challenges and costs associated with CO2 separation from flue gas and transportation of the separated CO2 from the point source to an appropriate sequestration target was analyzed. The report includes the selection of a specific coal-fired power plant for the application of CO2 separation technology. An appropriate CO2 separation technology was identified from existing commercial technologies. The report also includes a process design for the chosen technology tailored to the selected power plant that used to obtain accurate costs of separating the CO2 from the flue gas. In addition, an analysis of the costs for compression and transportation of the CO2 from the point-source to an appropriate coal bed sequestration site was included in the report.

New separation technique. Catalytically functionated separation membrane

Energy Technology Data Exchange (ETDEWEB)

Urgami, Tadashi [Kansai Univ., Osaka (Japan)

1989-02-01

This report introduces research examples, showing the fundamental principle of the membrane by separating the catalytically functionated separation membrane into enzyme fixing separation membrane, polymerized metal complex separation membrane and polymer catalyst separation membrane. This membrane can achieve both functions of separation and catalytic reaction simultaneously and has sufficient possibility to combine powerful functions. Enzyme fixing separation membrane is prepared by carrier combination method, bridging method or covering method and the enzyme fixing method with polymerized complex in which enzyme is controlled to prevent the activity lowering as much as possible and enzyme is fixed from an aqueous solution into polymer membrane. This membrane is applied to the continuous manufacturing of invert sugar from cane sugar and adsorption and removing of harmful substances from blood by utilizing both micro-capsuled urease and active carbon. Alginic acid-copper (II) complex membrane is used for the polymerized metal complex membrane and polystyrene sulfonate membrane is used for the polymer catalyst separation membrane. 28 refs., 4 figs., 1 tabs.

Lunar neutron source function

International Nuclear Information System (INIS)

Kornblum, J.J.

1974-01-01

The search for a quantitative neutron source function for the lunar surface region is justified because it contributes to our understanding of the history of the lunar surface and of nuclear process occurring on the moon since its formation. A knowledge of the neutron source function and neutron flux distribution is important for the interpretation of many experimental measurements. This dissertation uses the available pertinent experimental measurements together with theoretical calculations to obtain an estimate of the lunar neutron source function below 15 MeV. Based upon reasonable assumptions a lunar neutron source function having adjustable parameters is assumed for neutrons below 15 MeV. The lunar neutron source function is composed of several components resulting from the action of cosmic rays with lunar material. A comparison with previous neutron calculations is made and significant differences are discussed. Application of the results to the problem of lunar soil histories is examined using the statistical model for soil development proposed by Fireman. The conclusion is drawn that the moon is losing mass

Swirling Combustor Energy Converter: H2/Air Simulations of Separated Chambers

Directory of Open Access Journals (Sweden)

Angelo Minotti

2015-09-01

Full Text Available This work reports results related to the “EU-FP7-HRC-Power” project aiming at developing micro-meso hybrid sources of power. One of the goals of the project is to achieve surface temperatures up to more than 1000 K, with a ∆T ≤ 100 K, in order to be compatible with a thermal/electrical conversion by thermo-photovoltaic cells. The authors investigate how to reach that goal adopting swirling chambers integrated in a thermally-conductive and emitting element. The converter consists of a small parallelepiped brick inside two separated swirling meso-combustion chambers, which heat up the parallelepiped, emitting material by the combustion of H2 and air at ambient pressure. The overall dimension is of the order of cm. Nine combustion simulations have been carried out assuming detailed chemistry, several length/diameter ratios (Z/D = 3, 5 and 11 and equivalence ratios (0.4, 0.7 and 1; all are at 400 W of injected chemical power. Among the most important results are the converter surfaces temperatures, the heat loads, provided to the environment, and the chemical efficiency. The high chemical efficiency, h > 99.9%, is due to the relatively long average gas residence time coupled with the fairly good mixing due to the swirl motion and the impinging air/fuel jets that provide heat and radicals to the flame.

Preparation and characterization of alpha sources as standards in the actinides separation; Preparacion y caracterizacion de fuentes alfa como estandares en la separacion de actinidos

Energy Technology Data Exchange (ETDEWEB)

Monroy G, F.; Escobar A, L.; Zepeda R, C. P.; Balcazar, M., E-mail: fabiola.monroy@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

2017-09-15

The radioisotopes Am-243, Cm-244, Pu-242 and U-232 are used as radioactive tracers in the processes of separation and quantification of the radioisotopes of Am, Cm, Pu and U contained in radioactive and nuclear wastes, with the purpose of determining the efficiency of said processes. For this, in this work, alpha sources of Am-243, Cm-244, Pu-242 and U-232 standards were prepared by two methods: evaporation and electro-deposition, and they were analyzed by means of alpha spectrometry to verify the properties of these radioactive standards. The alpha sources prepared by electro-deposition were analyzed by Raman spectrometry to determine the chemical form in which the actinide was deposited; the good homogeneity in the distribution of the deposit was determined with solid nuclear trace detectors. The resolution of the alpha spectra obtained with surface barrier detectors of the standards is greater when deposited by electro-deposition. The FWHM of the alpha sources prepared by electro-deposition is always lower than that prepared by evaporation. Actinides are electrodeposited in the form of hydroxides and oxo compounds. (Author)

Life Cycle Inventory & Assessment Report: Separation of Digested Fattening Pig Slurry for Optimal P Concentration, Denmark

DEFF Research Database (Denmark)

Wesnæs, Marianne; Hamelin, Lorie; Wenzel, Henrik

management chain” for a combination of techniques: Source-segregation of manure from fattening pigs, using the solid part from the source-segregation for biogas production, utilising the biogas for heat and electricity production, separating the digested pig manure after the biogas plant in order to optimize......The purpose of this Life Cycle Assessment report is to investigate the potential for separating the digested pig manure after the biogas plant in order to optimise the utilisation of the phosphorous content of the manure. By separating, the phosphorous rich solid fraction can be brought to fields...

Separation and preparation of "6"2Ni isotope

International Nuclear Information System (INIS)

Ren Xiuyan; Mi Yajing; Zeng Ziqiang; Li Gongliang; Tu Rui

2014-01-01

Micro nuclear battery is the perfect power of space craft equipment. "6"3Ni is the core operation material of the "6"3Ni battery. It can produce radioisotope "6"3Ni while high abundance "6"2Ni is irradiated in the reactor. In order to meet the requirements of the abundance and the purity, research of the separation for "6"2Ni isotope was developed. The magnetic field and beam transmission status were simulated. The improvement designs of the ion source and the collector pocket were carried out. The process flow of high abundance "6"2Ni using electromagnetic separation method was established. The experiment of "6"2Ni isotope was developed by using electromagnetism isotope separator. The results show that the enrichment of "6"2Ni isotope is more than 90%. (authors)

Comparison of gas membrane separation cascades using conventional separation cell and two-unit separation cells

International Nuclear Information System (INIS)

Ohno, Masayoshi; Morisue, Tetsuo; Ozaki, Osamu; Miyauchi, Terukatsu.

1978-01-01

The adoption of two-unit separation cells in radioactive rare gas membrane separation equipment enhances the separation factor, but increases the required membrane area and compressive power. An analytical economic evaluation was undertaken to compare the conventional separation cell with the two-unit separation cells, adopting as parameters the number of cascade stages, the membrane area and the operating power requirements. This paper describes the models used for evaluating the separation performance and the economics of cascade embodying these different concepts of separation cell taken up for study, and the results obtained for the individual concepts are mutually compared. It proved that, in respect of the number required of cascade stages, of operating power requirements and of the annual expenditure, better performance could always be expected of the two-unit separation cells as compared with the conventional separation cell, at least in the range of parameters adopted in this study. As regards the minimum membrane area, the conventional separation cell and the series-type separation cell yielded almost the same values, with the parallel-type separation cell falling somewhat behind. (auth.)

Isomer separation of $^{70g}Cu$ and $^{70m}Cu$ with a resonance ionization laser ion source

CERN Document Server

Köster, U; Mishin, V I; Weissman, L; Huyse, M; Kruglov, K; Müller, W F; Van Duppen, P; Van Roosbroeck, J; Thirolf, P G; Thomas, H C; Weisshaar, D W; Schulze, W; Borcea, R; La Commara, M; Schatz, H; Schmidt, K; Röttger, S; Huber, G; Sebastian, V; Kratz, K L; Catherall, R; Georg, U; Lettry, Jacques; Oinonen, M; Ravn, H L; Simon, H

2000-01-01

Radioactive copper isotopes were ionized with the resonance ionization laser ion source at the on-line isotope separator ISOLDE (CERN). Using the different hyperfine structure in the 3d/sup 10/ 4s /sup 2/S/sub 1/2/-3d/sup 10/ 4p /sup 2/P/sub 1/2//sup 0/ transition the low- and high-spin isomers of /sup 70/Cu were selectively enhanced by tuning the laser wavelength. The light was provided by a narrow-bandwidth dye laser pumped by copper vapor lasers and frequency doubled in a BBO crystal. The ground state to isomeric state intensity ratio could be varied by a factor of 30, allowing to assign gamma transitions unambiguously to the decay of the individual isomers. It is shown that the method can also be used to determine magnetic moments. In a first experiment for the 1/sup +/ ground state of /sup 70/Cu a magnetic moment of (+)1.8(3) mu /sub N/ and for the high-spin isomer of /sup 70/Cu a magnetic moment of (+or-)1.2(3) mu /sub N/ could be deduced. (20 refs).

Method for isotope separation by photodeflection

International Nuclear Information System (INIS)

Bernhardt, A.F.

1977-01-01

In the method of separating isotopes wherein a desired isotope species is selectively deflected out of a beam of mixed isotopes by irradiating the beam with a directed beam of light of narrowly defined frequency which is selectively absorbed by the desired species, the improvement comprising irradiating the deflected beam with light from other light sources whose frequencies are selected to cause the depopulation of any metastable excited states

Progress in ISOL target-ion source systems

Energy Technology Data Exchange (ETDEWEB)

Koester, U. [Institut Laue Langevin, 6 Rue Jules Horowitz, F-38042 Grenoble Cedex 9 (France); ISOLDE, CERN, CH-1211 Geneve 23 (Switzerland)], E-mail: koester@ill.fr; Arndt, O. [HGF VISTARS and Institut fuer Kernchemie, Johannes-Gutenberg Universitaet Mainz, D-55128 Mainz (Germany); Bouquerel, E.; Fedoseyev, V.N. [ISOLDE, CERN, CH-1211 Geneve 23 (Switzerland); Franberg, H. [ISOLDE, CERN, CH-1211 Geneve 23 (Switzerland); Laboratory for Radio- and Environmental Chemistry, Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Joinet, A. [ISOLDE, CERN, CH-1211 Geneve 23 (Switzerland); Centre d' Etude Spatiale des Rayonnements, 9 Av. du Colonel Roche, F-31028 Toulouse Cedex 4 (France); Jost, C. [HGF VISTARS and Institut fuer Kernchemie, Johannes-Gutenberg Universitaet Mainz, D-55128 Mainz (Germany); Kerkines, I.S.K. [Laboratory of Physical Chemistry, National and Kapodistrian University of Athens, Department of Chemistry, Zografou 157 71, GR (Greece); Cherry L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, Atlanta, GA 30322 (United States); Kirchner, R. [Gesellschaft fuer Schwerionenforschung, Planckstr. 1, D-64291 Darmstadt (Germany)

2008-10-15

The heart of every ISOL (isotope separation on-line) facility is its target and ion source system. Its efficiency, selectivity and rapidity is decisive for the production of intense and pure ion beams of short-lived isotopes. Recent progress in ISOL target and ion source technology is discussed at the examples of radioactive ion beams of exotic zinc and tin isotopes that were purified by isothermal chromatography and molecular sideband separation respectively. An outlook is given to which other elements these purification methods are applicable.

Progress in ISOL target-ion source systems

International Nuclear Information System (INIS)

Koester, U.; Arndt, O.; Bouquerel, E.; Fedoseyev, V.N.; Franberg, H.; Joinet, A.; Jost, C.; Kerkines, I.S.K.; Kirchner, R.

2008-01-01

The heart of every ISOL (isotope separation on-line) facility is its target and ion source system. Its efficiency, selectivity and rapidity is decisive for the production of intense and pure ion beams of short-lived isotopes. Recent progress in ISOL target and ion source technology is discussed at the examples of radioactive ion beams of exotic zinc and tin isotopes that were purified by isothermal chromatography and molecular sideband separation respectively. An outlook is given to which other elements these purification methods are applicable.

Pilot and Controller Evaluations of Separation Function Allocation in Air Traffic Management

Science.gov (United States)

Wing, David; Prevot, Thomas; Morey, Susan; Lewis, Timothy; Martin, Lynne; Johnson, Sally; Cabrall, Christopher; Como, Sean; Homola, Jeffrey; Sheth-Chandra, Manasi; style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20130014930'); toggleEditAbsImage('author_20130014930_show'); toggleEditAbsImage('author_20130014930_hide'); "> style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20130014930_show"> style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20130014930_hide">

2013-01-01

Two human-in-the-loop simulation experiments were conducted in coordinated fashion to investigate the allocation of separation assurance functions between ground and air and between humans and automation. The experiments modeled a mixed-operations concept in which aircraft receiving ground-based separation services shared the airspace with aircraft providing their own separation service (i.e., self-separation). Ground-based separation was provided by air traffic controllers without automation tools, with tools, or by ground-based automation with controllers in a managing role. Airborne self-separation was provided by airline pilots using self-separation automation enabled by airborne surveillance technology. The two experiments, one pilot-focused and the other controller-focused, addressed selected key issues of mixed operations, assuming the starting point of current-day operations and modeling an emergence of NextGen technologies and procedures. In the controller-focused experiment, the impact of mixed operations on controller performance was assessed at four stages of NextGen implementation. In the pilot-focused experiment, the limits to which pilots with automation tools could take full responsibility for separation from ground-controlled aircraft were tested. Results indicate that the presence of self-separating aircraft had little impact on the controllers' ability to provide separation services for ground-controlled aircraft. Overall performance was best in the most automated environment in which all aircraft were data communications equipped, ground-based separation was highly automated, and self-separating aircraft had access to trajectory intent information for all aircraft. In this environment, safe, efficient, and highly acceptable operations could be achieved for twice today's peak airspace throughput. In less automated environments, reduced trajectory intent exchange and manual air traffic control limited the safely achievable airspace throughput and

Classical-processing and quantum-processing signal separation methods for qubit uncoupling

Science.gov (United States)

Deville, Yannick; Deville, Alain

2012-12-01

The Blind Source Separation problem consists in estimating a set of unknown source signals from their measured combinations. It was only investigated in a non-quantum framework up to now. We propose its first quantum extensions. We thus introduce the Quantum Source Separation field, investigating both its blind and non-blind configurations. More precisely, we show how to retrieve individual quantum bits (qubits) only from the global state resulting from their undesired coupling. We consider cylindrical-symmetry Heisenberg coupling, which e.g. occurs when two electron spins interact through exchange. We first propose several qubit uncoupling methods which typically measure repeatedly the coupled quantum states resulting from individual qubits preparations, and which then statistically process the classical data provided by these measurements. Numerical tests prove the effectiveness of these methods. We then derive a combination of quantum gates for performing qubit uncoupling, thus avoiding repeated qubit preparations and irreversible measurements.

The Dirac equation in external fields: Variable separation in Cartesian coordinates

International Nuclear Information System (INIS)

Shishkin, G.V.; Cabos, W.D.

1991-01-01

The method of separation of variables in the Dirac equation proposed in an earlier work by one of the present authors [J. Math. Phys. 30, 2132 (1989)] is developed for the complete set of interactions of the Dirac particle. The essence of the method consists of the separation of the first-order matrix differential operators that define the dependence of the Dirac bispinor on the related variables, but commutation of such operators with or between the operator of the equation is not assumed. This approach, which is perfectly justified in the presence of gravitational [Theor. Math. Phys. 70, 204 (1987)] or vector fields [J. Math. Phys. 30, 2132 (1989)], permits one to find all the possibilities of separation of variables in the Dirac equation in the case of the most general set of external fields. The complete set of interactions of the Dirac particle is determined by the symmetry group of equations, namely, viz. the SU(4) group. The interactions are scalar, vector, tensor, pseudovector and pseudoscalar. The analysis in this article is limited to Cartesian coordinates. The corresponding results for the general curvilinear coordinates will be presented in a future paper

Installation of an isotope separator in Debrecen

International Nuclear Information System (INIS)

Gacsi, Z.; Gulyas, J.; Vitez, A.; Csige, L.; Krasznahorkay, A.

2005-01-01

Complete text of publication follows. An isotope separator named OSIRIS was decommissioned in Studsvik, Sweden last July. Researchers there offered this equipment to us for dismantling and moving it over to ATOMKI in Debrecen for installation at the cyclotron lab and save and use it in nuclear physics and other sciences where stable and radioactive isotopes are used extensively for fundamental and applied research. Since the separator was used to separate radioactive isotopes, the ion source with its beam extracting, shaping, and transporting accessories, as well as the lining inside the bending magnet, furthermore the beam diagnostic and shaping elements in the 'switchyard' part of the separator had to stay in Studsvik because of the high radioactive contamination. In order to operate this equipment, first we have to design and manufacture these parts together with a new endstation for the collection and handling of the separated isotopes. Parallel with the installation, we also concentrate on different applications of an isotope separator, including separation of stable isotopes for labelling special compounds used in many branches of sciences, medical care, and industry, and on studying single ion implantation possibilities, as well as on the production of special targets for nuclear physics research. First we want to separate stable isotopes, and then, when we overcome all technical pitfalls, we will consider using this equipment to separate radioactive isotopes as well. Our intention is to have this equipment available to anyone at ATOMKI and elsewhere interested in using its capabilities in their own research fields. Consequently, all comments, suggestion, and ideas are welcome now and continuously, since the design and manufacture of parts can then be oriented by taking into account all the suggestions as much as possible. (author)

Removal of power line interference of space bearing vibration signal based on the morphological filter and blind source separation

Science.gov (United States)

Dong, Shaojiang; Sun, Dihua; Xu, Xiangyang; Tang, Baoping

2017-06-01

Aiming at the problem that it is difficult to extract the feature information from the space bearing vibration signal because of different noise, for example the running trend information, high-frequency noise and especially the existence of lot of power line interference (50Hz) and its octave ingredients of the running space simulated equipment in the ground. This article proposed a combination method to eliminate them. Firstly, the EMD is used to remove the running trend item information of the signal, the running trend that affect the signal processing accuracy is eliminated. Then the morphological filter is used to eliminate high-frequency noise. Finally, the components and characteristics of the power line interference are researched, based on the characteristics of the interference, the revised blind source separation model is used to remove the power line interferences. Through analysis of simulation and practical application, results suggest that the proposed method can effectively eliminate those noise.

Aging changes 3D perception: Evidence for hemispheric rebalancing of lateralized processes.

Science.gov (United States)

Andrews, Bridget; d'Avossa, Giovanni; Sapir, Ayelet

2017-05-01

When judging the 3D shape of a shaded image, young observers assume that the light source is placed above and to the left. This leftward bias has been attributed to hemispheric lateralization or experiential factors. Since aging is associated with loss of hemispheric lateralization, in the current study we measured the effect of aging on the assumed light source direction. Older participants exhibited, on average, a decreased left bias compared to young participants, as well as greater within-group variability in the distribution of assumed light source directions. In a separate sample of young and old participants, we replicated the age related effect in the assumed light source direction. Furthermore, in both young and old participants the assumed light source direction and the lateralized bias in a line bisection task were correlated. These findings suggest that diminished hemispheric lateralization, which accompanies aging, may affect the perception of the 3D structure of shaded surfaces. Shape from shading may thus provide a simple behavioral tool to track age related changes in hemispheric organization. Copyright © 2017 Elsevier Ltd. All rights reserved.

Method and apparatus for suppressing electron generation in a vapor source for isotope separation

International Nuclear Information System (INIS)

Janes, G.S.

1979-01-01

A system for applying accelerating forces to ionized particles of a vapor in a manner to suppress the flow of electron current from the vapor source. The accelerating forces are applied as an electric field in a configuration orthogonal to a magnetic field. The electric field is applied between one or more anodes in the plasma and one or more cathodes operated as electron emitting surfaces. The circuit for applying the electric field floats the cathodes with respect to the vapor source, thereby removing the vapor source from the circuit of electron flow through the plasma and suppressing the flow of electrons from the vapor source. The potential of other conducting structures contacting the plasma is controlled at or permitted to seek a level which further suppresses the flow of electron currents from the vapor source. Reducing the flow of electrons from the vapor source is particularly useful where the vapor is ionized with isotopic selectivity because it avoids superenergization of the vapor by the electron current

Apparatus for diffusion separation

International Nuclear Information System (INIS)

Nierenberg, W.A.

1976-01-01

A diffuser separator apparatus is described which comprises a plurality of flow channels in a single stage. Each of said channels has an inlet port and an outlet port and a constant cross sectional area between said ports. At least a portion of the defining surface of each of said channels is a diffusion separation membrane, and each of said channels is a different cross sectional area. Means are provided for connecting said channels in series so that each successive channel of said series has a smaller cross sectional area than the previous channel of said series. Also provided are a source of gaseous mixture, individual means for flowing said gaseous mixture to the inlet port of each of said channels, gas receiving and analyzing means, individual means for flowing gas passing from each of said outlet ports and means for flowing gas passing through said membranes to said receiving and analyzing means, and individual means for connecting the outlet port of each channel with the inlet port of the channel having the next smaller cross sectional area

Calcium phosphate nuclear materials: apatitic ceramics for separated wastes

International Nuclear Information System (INIS)

Carpena, J.; Lacout, J.L.

2005-01-01

Is it feasible to elaborate conditioning materials for separated high activity nuclear wastes, as actinides or fission products? Specific materials have been elaborated so that the waste is incorporated within the crystalline structure of the most stable calcium phosphate, i.e. apatite. This mineral is able to sustain high irradiation doses assuming a well chosen chemical composition. Mainly two different ways of synthesis have been developed to produce hard apatite ceramics that can be used to condition nuclear wastes. Here we present a data synthesis regarding the elaboration of these apatite nuclear materials that includes experiments on crystallo-chemistry, chemical analysis, leaching and irradiation tests performed for the past fifteen years. (authors)

Plasma Separation Process: Betacell (BCELL) code: User's manual. [Bipolar barrier junction

Energy Technology Data Exchange (ETDEWEB)

Taherzadeh, M.

1987-11-13

The emergence of clearly defined applications for (small or large) amounts of long-life and reliable power sources has given the design and production of betavoltaic systems a new life. Moreover, because of the availability of the plasma separation program, (PSP) at TRW, it is now possible to separate the most desirable radioisotopes for betacell power generating devices. A computer code, named BCELL, has been developed to model the betavoltaic concept by utilizing the available up-to-date source/cell parameters. In this program, attempts have been made to determine the betacell energy device maximum efficiency, degradation due to the emitting source radiation and source/cell lifetime power reduction processes. Additionally, comparison is made between the Schottky and PN junction devices for betacell battery design purposes. Certain computer code runs have been made to determine the JV distribution function and the upper limit of the betacell generated power for specified energy sources. A Ni beta emitting radioisotope was used for the energy source and certain semiconductors were used for the converter subsystem of the betacell system. Some results for a Promethium source are also given here for comparison. 16 refs.

How to separate ionic liquids: Use of Hydrophilic Interaction Liquid Chromatography and mixed mode phases

International Nuclear Information System (INIS)

Lamouroux, C.

2011-01-01

This chromatographic study deals with the development of a convenient and versatile method to separate Room Temperature Ionic Liquids. Different modes of chromatography were studied. The study attempts to answer the following question: 'what were the most important interactions for the separation of ionic liquids?'. The results show that the essential interactions to assure a good retention of RTILs are the ionic ones and that hydrophobic interactions play a role in the selectivity of the separation. The separation of five imidazolium salt with a traditional dial columns in Hydrophilic Interaction Chromatography (HILIC) was demonstrated. It shows that neutral diol grafted column allows an important retention that we assume is due to the capability of diol to develop a thick layer of water. Furthermore, stationary phase based on mixed interaction associating ion exchange and hydrophobic properties were studied. Firstly, it will be argued that it is possible to separate RTILs with a convenient retention and resolution according to a reverse phase elution with the Primesep columns made of a brush type long alkyl chain with an embedded negatively charged functional group. Secondly, a successful separation of RTILs in HILIC mode with a mixed phase column containing a cationic exchanger and a hydrophobic octyl chain length will be demonstrated. (author)

Scale separation closure and Alfven wave turbulence

International Nuclear Information System (INIS)

Chen, C.Y.; Mahajan, S.M.

1985-04-01

Based on the concept of scale separation between coherent response function and incoherent source for renormalized turbulence theories, a closure scheme is proposed. A model problem dealing with shear-Alfven wave turbulence is numerically solved; the solution explicitly shows expected turbulence features such as frequency shift from linear modes, band-broadening, and a power law dependence for the turbulence spectrum

Experimental Research of Machineless Energy Separation Effect Influenced by Shock Waves

Directory of Open Access Journals (Sweden)

S. S. Popovich

2016-01-01

Full Text Available The paper presents experimental research results of machineless energy separation effect with transversal ribs in supersonic channel. The energy separation effect assumes a physical division of the inlet flow into two or more flows, each having different stagnation temperature. Among well-known energy separation effects noted there are Ranque-Hilsch vortex tubes, Hartmann-Sprenger resonance tubes, pulsating tubes and some others.A working principle of device under study is based on thermal interaction between subsonic and supersonic gas flows through a heat-conducting division wall. This energy separation method was proposed by academician Leontiev and was patented in 1998. A number of references for PhD theses, articles, and conference proceedings devoted to the research of “Leontiev tube” have been mentioned in the paper. Efficiency factors for energy separation device performability have been analyzed in detail. The main attention was focused on the phenomenon of shock waves generation in supersonic channel of Leontiev tube.Experiment was carried out in the air prototype of energy separation device with supersonic flow Mach numbers 1.9 and 2.5, stagnation temperatures 40°С and 70°С, and for uni-flow and counter-flow air moving direction in subsonic and supersonic channels. Shock waves have been generated by means of circular ribs in supersonic channel of energy separation device. The research was carried out by means of infrared thermal imaging, thermocouples, total and static pressure probes, and modern National Insturments automation equipment. The work shows that shock waves have no negative influence on energy separation effect. A conclusion is made that unexpected shock wave generation in supersonic channel will not cause operability loss. It was gained that counter-flow regime is more efficient than uni-flow. Energy separation effect also appears to be higher with the rise of Mach number and flow initial stagnation temperature

Separation efficiency of the MASHA facility for short-lived mercury isotopes

Science.gov (United States)

Rodin, A. M.; Belozerov, A. V.; Chernysheva, E. V.; Dmitriev, S. N.; Gulyaev, A. V.; Gulyaeva, A. V.; Itkis, M. G.; Kliman, J.; Kondratiev, N. A.; Krupa, L.; Novoselov, A. S.; Oganessian, Yu. Ts.; Podshibyakin, A. V.; Salamatin, V. S.; Siváček, I.; Stepantsov, S. V.; Vanin, D. V.; Vedeneev, V. Yu.; Yukhimchuk, S. A.; Granja, C.; Pospisil, S.

2014-06-01

The mass-separator MASHA built to identify Super Heavy Elements by their mass-to-charge ratios is described. The results of the off- and on-line measurements of its separation efficiency are presented. In the former case four calibrated leaks of noble gases were used. In the latter the efficiency was measured via 284 MeV Ar beam and with using the hot catcher. The ECR ion source was used in both cases. The -radioactive isotopes of mercury produced in the complete fusion reaction Ar+SmHg+xn were detected at the mass-separator focal plane. The half-lives and the separation efficiency for the short-lived mercury isotopes were measured. Potentialities of the MEDIPIX detector system have been demonstrated for future use at the mass-separator MASHA.

Niche separation of pollen beetle parasitoids

Directory of Open Access Journals (Sweden)

Josef eBerger

2015-05-01

Full Text Available Species with similar resource requirements are commonly assumed to competitively exclude each other, unless they differentiate their ecological niches. Hence, parasitoid wasps that use the same host species need to find some way to avoid competition. The aim of this study was to identify the role of volatile cues from oilseed rape plants and the larval host in niche separation between three coexisting parasitoid species. We examined how Phradis interstitialis, Phradis morionellus and Tersilochus heterocerus, sympatric parasitoids of Brassicogethes aeneus, differ in their abundances, distribution on buds and flowers, and oviposition behavior in the field. Furthermore, we tested their preferences for odours from uninfested and infested oilseed rape plants in the bud and flowering stage, and their preferences for odours from three developmental stages of pollen beetle larvae in a two-choice olfactometer bioassay.P. interstitialis was active in the field early in the season, preferred odours of infested buds versus uninfested, and oviposited into buds which contained only pollen beetle eggs, while P. morionellus was active late in the season, preferred odours of infested buds as well as odours of infested flowers over uninfested, and oviposited into buds which contained only larvae. T. heterocerus was active throughout the season, and preferred odours of infested flowers over uninfested. Neither Phradis species were attracted to larval odours, whereas T. heterocerus was attracted to odours from first-instar pollen beetle larvae both in the absence of plant odours, and when presented simultaneously with uninfested plant odour.This suggests that the two Phradis species are separated on a temporal scale and that they parasitize different host stages, while the larval parasitoids P. morionellus and T. heterocerus are separated by choice of microhabitat. The former oviposits into larvae in buds, and the latter in flowers.

On-line mass separator of superheavy atoms

International Nuclear Information System (INIS)

Oganesyan, Yu.Ts.

2002-01-01

The concept is presented of an on-line Mass Analyzer of SuperHeavy Atoms (MASHA) dedicated to the separation and determination of the mass and decay properties of new elements and isotopes produced in heavy-ion induced reactions. The new nuclides with half-lives T 1/2 ≥ 1 s are transported to an ECR-source working at a frequency of 2.45 GHz and are separated by mass with a mass resolution of M/ΔM ∼ 1500. In the focal plane of the magnetic analyzer a front strip detector surrounded by side detectors will be placed to determine the mass according to the signals from the detected α-particles or fission fragments with efficiency of about 90 %. In comparison to other existing in-flight recoil separators, the present setup will be characterized by higher efficiency and high selectivity relative to background reaction products. The setup MASHA may be used also in the investigation of nuclear reactions of different type induced by stable and radioactive beams

On-Line Mass Separator of Superheavy Atoms

CERN Document Server

Oganessian, Yu T

2002-01-01

The concept is presented of an on-line Mass Analyzer of SuperHeavy Atoms (MASHA) dedicated to the separation and determination of the mass and decay properties of new elements and isotopes produced in heavy-ion induced reactions. The new nuclides with half-lives T_{1/2}\\ge 1 s are transported to an ECR-source working at a frequency of 2.45 GHz and are separated by mass with a mass resolution of M/\\Delta M\\sim 1500. In the focal plane of the magnetic analyzer a front strip detector surrounded by side detectors will be placed to determine the mass according to the signals from the detected alpha-particles or fission fragments with efficiency of about 90 %. In comparison to other existing in-flight recoil separators, the present setup will be characterized by higher efficiency and high selectivity relative to background reaction products. The setup MASHA may be used also in the investigation of nuclear reactions of different type induced by stable and radioactive beams.

Pathogens and pharmaceuticals in source-separated urine in eThekwini, South Africa.

Science.gov (United States)

Bischel, Heather N; Özel Duygan, Birge D; Strande, Linda; McArdell, Christa S; Udert, Kai M; Kohn, Tamar

2015-11-15

In eThekwini, South Africa, the production of agricultural fertilizers from human urine collected from urine-diverting dry toilets is being evaluated at a municipality scale as a way to help finance a decentralized, dry sanitation system. The present study aimed to assess a range of human and environmental health hazards in source-separated urine, which was presumed to be contaminated with feces, by evaluating the presence of human pathogens, pharmaceuticals, and an antibiotic resistance gene. Composite urine samples from households enrolled in a urine collection trial were obtained from urine storage tanks installed in three regions of eThekwini. Polymerase chain reaction (PCR) assays targeted 9 viral and 10 bacterial human pathogens transmitted by the fecal-oral route. The most frequently detected viral pathogens were JC polyomavirus, rotavirus, and human adenovirus in 100%, 34% and 31% of samples, respectively. Aeromonas spp. and Shigella spp. were frequently detected gram negative bacteria, in 94% and 61% of samples, respectively. The gram positive bacterium, Clostridium perfringens, which is known to survive for extended times in urine, was found in 72% of samples. A screening of 41 trace organic compounds in the urine facilitated selection of 12 priority pharmaceuticals for further evaluation. The antibiotics sulfamethoxazole and trimethoprim, which are frequently prescribed as prophylaxis for HIV-positive patients, were detected in 95% and 85% of samples, reaching maximum concentrations of 6800 μg/L and 1280 μg/L, respectively. The antiretroviral drug emtricitabine was also detected in 40% of urine samples. A sulfonamide antibiotic resistance gene (sul1) was detected in 100% of urine samples. By coupling analysis of pathogens and pharmaceuticals in geographically dispersed samples in eThekwini, this study reveals a range of human and environmental health hazards in urine intended for fertilizer production. Collection of urine offers the benefit of

Influence of owners' attachment style and personality on their dogs' (Canis familiaris separation-related disorder.

Directory of Open Access Journals (Sweden)

Veronika Konok

Full Text Available Previous research has suggested that owners' attitude to their family dogs may contribute to a variety of behaviour problems in the dog, and authors assume that dogs with separation-related disorder (SRD attach differently to the owner than typical dogs do. Our previous research suggested that these dogs may have an insecure attachment style. In the present study we have investigated whether owners' attachment style, personality traits and the personality of the dog influence the occurrence of SRD in the dog. In an internet-based survey 1508 (1185 German and 323 Hungarian dog-owners filled in five questionnaires: Demographic questions, Separation Behaviour Questionnaire (to determine SRD, Human and Dog Big Five Inventory and Adult Attachment Scale. We found that with owners' higher score on attachment avoidance the occurrence of SRD in the dog increases. Dogs scoring higher on the neuroticism scale were more prone to develop SRD. Our results suggest that owners' attachment avoidance may facilitate the development of SRD in dogs. We assume that avoidant owners are less responsive to the dog's needs and do not provide a secure base for the dog when needed. As a result dogs form an insecure attachment and may develop SRD. However, there may be alternative explanations of our findings that we also discuss.

Influence of Owners’ Attachment Style and Personality on Their Dogs’ (Canis familiaris) Separation-Related Disorder

Science.gov (United States)

Konok, Veronika; Kosztolányi, András; Rainer, Wohlfarth; Mutschler, Bettina; Halsband, Ulrike; Miklósi, Ádám

2015-01-01

Previous research has suggested that owners’ attitude to their family dogs may contribute to a variety of behaviour problems in the dog, and authors assume that dogs with separation-related disorder (SRD) attach differently to the owner than typical dogs do. Our previous research suggested that these dogs may have an insecure attachment style. In the present study we have investigated whether owners’ attachment style, personality traits and the personality of the dog influence the occurrence of SRD in the dog. In an internet-based survey 1508 (1185 German and 323 Hungarian) dog-owners filled in five questionnaires: Demographic questions, Separation Behaviour Questionnaire (to determine SRD), Human and Dog Big Five Inventory and Adult Attachment Scale. We found that with owners’ higher score on attachment avoidance the occurrence of SRD in the dog increases. Dogs scoring higher on the neuroticism scale were more prone to develop SRD. Our results suggest that owners’ attachment avoidance may facilitate the development of SRD in dogs. We assume that avoidant owners are less responsive to the dog’s needs and do not provide a secure base for the dog when needed. As a result dogs form an insecure attachment and may develop SRD. However, there may be alternative explanations of our findings that we also discuss. PMID:25706147

Gaussian process based independent analysis for temporal source separation in fMRI

DEFF Research Database (Denmark)

Hald, Ditte Høvenhoff; Henao, Ricardo; Winther, Ole

2017-01-01

Functional Magnetic Resonance Imaging (fMRI) gives us a unique insight into the processes of the brain, and opens up for analyzing the functional activation patterns of the underlying sources. Task-inferred supervised learning with restrictive assumptions in the regression set-up, restricts...... the exploratory nature of the analysis. Fully unsupervised independent component analysis (ICA) algorithms, on the other hand, can struggle to detect clear classifiable components on single-subject data. We attribute this shortcoming to inadequate modeling of the fMRI source signals by failing to incorporate its...

Quantum separability and entanglement detection via entanglement-witness search and global optimization

International Nuclear Information System (INIS)

Ioannou, Lawrence M.; Travaglione, Benjamin C.

2006-01-01

We focus on determining the separability of an unknown bipartite quantum state ρ by invoking a sufficiently large subset of all possible entanglement witnesses given the expected value of each element of a set of mutually orthogonal observables. We review the concept of an entanglement witness from the geometrical point of view and use this geometry to show that the set of separable states is not a polytope and to characterize the class of entanglement witnesses (observables) that detect entangled states on opposite sides of the set of separable states. All this serves to motivate a classical algorithm which, given the expected values of a subset of an orthogonal basis of observables of an otherwise unknown quantum state, searches for an entanglement witness in the span of the subset of observables. The idea of such an algorithm, which is an efficient reduction of the quantum separability problem to a global optimization problem, was introduced by [Ioannou et al., Phys. Rev. A 70, 060303(R)], where it was shown to be an improvement on the naive approach for the quantum separability problem (exhaustive search for a decomposition of the given state into a convex combination of separable states). The last section of the paper discusses in more generality such algorithms, which, in our case, assume a subroutine that computes the global maximum of a real function of several variables. Despite this, we anticipate that such algorithms will perform sufficiently well on small instances that they will render a feasible test for separability in some cases of interest (e.g., in 3x3 dimensional systems)

Comparative table of various energy sources

Energy Technology Data Exchange (ETDEWEB)

1976-08-01

This table provides wide informations on the technological facets of various sources of primary energy. One of the outstanding features of this table is that it exposes and compares various technological problems involved in the energy conversion processes. The primary energy sources treated here are the solar energy (heat and light are treated separately), the geothermal energy, coal (gasification and liquefaction are treated separately), oil, natural gas, oceano-energy (tidal energy, temperature difference, and wave energy are treated separately), organic wastes, oil shale, tar sand, hydraulic power, wind power, biomass, uranium, thorium, and deuterium and lithium. On the other hand, the comparisons are made in three major items, i.e. charactersitics as natural resources, conversion or refinement to secondary energy sources, and economical characteristics. The first item includes the estimated and recognized amount of deposits, easiness of mining, storage, and transportation, and cleanliness and safety. As for conversion characteristics, the easiness, controlability, efficiency, cleanliness, and safety of various conversion processes are compared. Finally, as for economical problems, cost comparisons are made for gathering or mining those resources, including required energy input, man power, required facilities, and site conditions.

Separation of blended impulsive sources using an iterative estimation-subtraction algorithm

NARCIS (Netherlands)

Doulgeris, P.; Mahdad, A.; Blacquière, G.

2010-01-01

Traditional data acquisition practice dictates the existence of sufficient time intervals between the firing of sequential impulsive sources in the field. However, much attention has been drawn recently to the possibility of shooting in an overlapping fashion. Numerous publications have addressed

Project planning workshop 6-GeV synchrotron light source: Volume 1

International Nuclear Information System (INIS)

1986-01-01

A model 6 GeV synchrotron light source is described, and the costs, schedule, and manpower associated with producing such a synthrotron light source are summarized. A program consisting of a two-year pre-construction phase, a five-year construction phase, and a three-year post-construction phase and costing a total of $379.6 million is assumed

Rapid anion exchange separation of fermium with mineral acid-methyl alcohol mixed media

International Nuclear Information System (INIS)

Usuda, S.; Shinohara, N.; Ichikawa, S.; Suzuki, T.

1987-01-01

Anion exchange separation of 250 Fm (30 m) synthesized by the 12 C+ 242 Pu and 16 O+ 238 U reactions was investigated with mineral acid-methyl alcohol mixed media at elevated temperature. Fermium was chromatographically separated from the other transplutonium elements, the target materials and an Al catcher foil by anion exchange with mixtures of nitric acid and methyl alcohol. By use of the mixed media of hydrochloric acid and methyl alcohol, Fm together with Cf was separated from Al, Am, Cm, Pu, U and from major fission products. The separation systems are suitable for rapid separation and immediate alpha-counting source preparation of Fm. (author) 22 refs.; 4 figs

Revised accident source terms for light-water reactors

Energy Technology Data Exchange (ETDEWEB)

Soffer, L. [Nuclear Regulatory Commission, Washington, DC (United States)

1995-02-01

This paper presents revised accident source terms for light-water reactors incorporating the severe accident research insights gained in this area over the last 15 years. Current LWR reactor accident source terms used for licensing date from 1962 and are contained in Regulatory Guides 1.3 and 1.4. These specify that 100% of the core inventory of noble gases and 25% of the iodine fission products are assumed to be instantaneously available for release from the containment. The chemical form of the iodine fission products is also assumed to be predominantly elemental iodine. These assumptions have strongly affected present nuclear air cleaning requirements by emphasizing rapid actuation of spray systems and filtration systems optimized to retain elemental iodine. A proposed revision of reactor accident source terms and some im implications for nuclear air cleaning requirements was presented at the 22nd DOE/NRC Nuclear Air Cleaning Conference. A draft report was issued by the NRC for comment in July 1992. Extensive comments were received, with the most significant comments involving (a) release fractions for both volatile and non-volatile species in the early in-vessel release phase, (b) gap release fractions of the noble gases, iodine and cesium, and (c) the timing and duration for the release phases. The final source term report is expected to be issued in late 1994. Although the revised source terms are intended primarily for future plants, current nuclear power plants may request use of revised accident source term insights as well in licensing. This paper emphasizes additional information obtained since the 22nd Conference, including studies on fission product removal mechanisms, results obtained from improved severe accident code calculations and resolution of major comments, and their impact upon the revised accident source terms. Revised accident source terms for both BWRS and PWRS are presented.

Mixing Matrix Estimation of Underdetermined Blind Source Separation Based on Data Field and Improved FCM Clustering

Directory of Open Access Journals (Sweden)

Qiang Guo

2018-01-01

Full Text Available In modern electronic warfare, multiple input multiple output (MIMO radar has become an important tool for electronic reconnaissance and intelligence transmission because of its anti-stealth, high resolution, low intercept and anti-destruction characteristics. As a common MIMO radar signal, discrete frequency coding waveform (DFCW has a serious overlap of both time and frequency, so it cannot be directly used in the current radar signal separation problems. The existing fuzzy clustering algorithms have problems in initial value selection, low convergence rate and local extreme values which will lead to the low accuracy of the mixing matrix estimation. Consequently, a novel mixing matrix estimation algorithm based on data field and improved fuzzy C-means (FCM clustering is proposed. First of all, the sparsity and linear clustering characteristics of the time–frequency domain MIMO radar signals are enhanced by using the single-source principal value of complex angular detection. Secondly, the data field uses the potential energy information to analyze the particle distribution, thus design a new clustering number selection scheme. Then the particle swarm optimization algorithm is introduced to improve the iterative clustering process of FCM, and finally get the estimated value of the mixing matrix. The simulation results show that the proposed algorithm improves both the estimation accuracy and the robustness of the mixing matrix.

Neutron sources and applications

Energy Technology Data Exchange (ETDEWEB)

Price, D.L. [ed.] [Argonne National Lab., IL (United States); Rush, J.J. [ed.] [National Inst. of Standards and Technology, Gaithersburg, MD (United States)

1994-01-01

Review of Neutron Sources and Applications was held at Oak Brook, Illinois, during September 8--10, 1992. This review involved some 70 national and international experts in different areas of neutron research, sources, and applications. Separate working groups were asked to (1) review the current status of advanced research reactors and spallation sources; and (2) provide an update on scientific, technological, and medical applications, including neutron scattering research in a number of disciplines, isotope production, materials irradiation, and other important uses of neutron sources such as materials analysis and fundamental neutron physics. This report summarizes the findings and conclusions of the different working groups involved in the review, and contains some of the best current expertise on neutron sources and applications.

Neutron sources and applications

International Nuclear Information System (INIS)

Price, D.L.; Rush, J.J.

1994-01-01

Review of Neutron Sources and Applications was held at Oak Brook, Illinois, during September 8--10, 1992. This review involved some 70 national and international experts in different areas of neutron research, sources, and applications. Separate working groups were asked to (1) review the current status of advanced research reactors and spallation sources; and (2) provide an update on scientific, technological, and medical applications, including neutron scattering research in a number of disciplines, isotope production, materials irradiation, and other important uses of neutron sources such as materials analysis and fundamental neutron physics. This report summarizes the findings and conclusions of the different working groups involved in the review, and contains some of the best current expertise on neutron sources and applications

Canine separation anxiety: strategies for treatment and management

Directory of Open Access Journals (Sweden)

Sargisson RJ

2014-10-01

Full Text Available Rebecca J Sargisson School of Psychology, University of Waikato, Tauranga, New ZealandAbstract: Dogs with separation-related behavior problems engage in unwanted behavior such as destruction of property and excessive vocalization when left alone, causing distress for both the dog and the owner, and often leading to the dog being relinquished or euthanized. I review research on factors likely to predispose dogs to developing separation anxiety and on the treatments available. Although research is equivocal, dogs seem to develop separation-related behavior problems if they are male, sourced from shelters or found, and separated from the litter before they are 60 days old. Protective factors include ensuring a wide range of experiences outside the home and with other people between the ages of 5–10 months, stable household routines and absences from the dog, and the avoidance of punishment. The most successful treatment for canine separation-related problems may be behavior modification that focuses on systematic desensitization and counterconditioning, which can be supplemented with medication in the initial stages. Where individual therapy from an animal behavior expert is not possible, advice to dog owners should be clear, simple, and contain five or fewer instructions to improve adherence. Advice is given for people seeking to adopt a dog, for new dog owners, and for existing dog owners who wish to treat their dog’s separation anxiety.Keywords: systematic desensitization, counterconditioning, medication, separation anxiety

Using Pitch, Amplitude Modulation, and Spatial Cues for Separation of Harmonic Instruments from Stereo Music Recordings

Directory of Open Access Journals (Sweden)

Bryan Pardo

2007-01-01

Full Text Available Recent work in blind source separation applied to anechoic mixtures of speech allows for improved reconstruction of sources that rarely overlap in a time-frequency representation. While the assumption that speech mixtures do not overlap significantly in time-frequency is reasonable, music mixtures rarely meet this constraint, requiring new approaches. We introduce a method that uses spatial cues from anechoic, stereo music recordings and assumptions regarding the structure of musical source signals to effectively separate mixtures of tonal music. We discuss existing techniques to create partial source signal estimates from regions of the mixture where source signals do not overlap significantly. We use these partial signals within a new demixing framework, in which we estimate harmonic masks for each source, allowing the determination of the number of active sources in important time-frequency frames of the mixture. We then propose a method for distributing energy from time-frequency frames of the mixture to multiple source signals. This allows dealing with mixtures that contain time-frequency frames in which multiple harmonic sources are active without requiring knowledge of source characteristics.

Lean premixed reacting flows with swirl and wall-separation zones in a contracting chamber

Science.gov (United States)

Zhang, Yuxin; Rusak, Zvi; Wang, Shixiao

2017-11-01

Low Mach number lean premixed reacting swirling flows with wall-separation zones in a contracting circular finite-length open chamber are studied. Assuming a complete reaction with high activation energy and chemical equilibrium behind the reaction zone, a nonlinear partial differential equation is derived for the solution of the flow stream function behind the reaction zone in terms of the inlet total enthalpy for a reacting flow, specific entropy and the circulation functions. Bifurcation diagrams of steady flows are described as the inlet swirl level is increased at fixed chamber contraction and reaction heat release. The approach is applied to an inlet solid-body rotation flow with constant profiles of the axial velocity, temperature and mixture reactant mass fraction. The computed results provide predictions of the critical inlet swirl levels for the first appearance of wall-separation states and for the size of the separation zone as a function of the inlet swirl ratio, Mach number, chamber contraction and heat release of the reaction. The methodology developed in this paper provides a theoretical feasibility for the development of the technology of swirl-assisted combustion where the reaction zone is supported and stabilized by a wall-separation zone.

Economic analysis of the need for advanced power sources

International Nuclear Information System (INIS)

Hardie, R.W.; Omberg, R.P.

1975-01-01

The purpose of this paper is to determine the economic need for an advanced power source, be it fusion, solar, or some other concept. However, calculations were also performed assuming abandonment of the LMFBR program, so breeder benefits are a by-product of this study. The model used was the ALPS linear programming system for forecasting optimum power growth patterns. Total power costs were calculated over a planning horizon from 1975 to 2041 and discounted at 7 1 / 2 percent. The benefit of a particular advanced power source is simply the reduction in total power cost resulting from its introduction. Since data concerning advanced power sources (APS) are speculative, parametric calculations varying introduction dates and capital costs about a hypothetical APS plant were performed. Calculations were also performed without the LMFBR to determine the effect of the breeder on the benefits of an advanced power source. Other data used in the study, such as the energy demand curve and uranium resource estimates, are given in the Appendix, and a list of the 11 power plants used in this study is given. Calculations were performed for APS introduction dates of 2001 and 2011. Estimates of APS capital costs included cases where it was assumed the costs were $50/kW and $25/kW higher than the LMFBR. In addition, cases where APS and LMFBR capital costs are identical were also considered. It is noted that the APS capital costs used in this study are not estimates of potential advanced power system plant costs, but were chosen to compute potential dollar benefits of advanced power systems under extremely optimistic assumptions. As a further example, all APS fuel cycle costs were assumed to be zero

Determining the Source of Water Vapor in a Cerium Oxide Electrochemical Oxygen Separator to Achieve Aviator Grade Oxygen

Science.gov (United States)

Graf, John; Taylor, Dale; Martinez, James

2014-01-01

]. Combined with a mechanical compressor, a Solid Electrolyte Oxygen Separator (SEOS) should be capable of producing ABO grade oxygen at pressures >2400 psia, on the space station. Feasibility tests using a SEOS integrated with a mechanical compressor identified an unexpected contaminant in the oxygen: water vapour was found in the oxygen product, sometimes at concentrations higher than 40 ppm (the ABO limit for water vapour is 7 ppm). If solid electrolyte membranes are really "infinitely selective" to oxygen as they are reported to be, where did the water come from? If water is getting into the oxygen, what other contaminants might get into the oxygen? Microscopic analyses of wafers, welds, and oxygen delivery tubes were performed in an attempt to find the source of the water vapour contamination. Hot and cold pressure decay tests were performed. Measurements of water vapour as a function of O2 delivery rate, O2 delivery pressure, and process air humidity levels were the most instructive in finding the source of water contamination (Fig 3). Water contamination was directly affected by oxygen delivery rate (doubling the oxygen production rate cut the water level in half). Water was affected by process air humidity levels and delivery pressure in a way that indicates the water was diffusing into the oxygen delivery system.

Characterising the vertical separation of shale-gas source rocks and aquifers across England and Wales (UK)

Science.gov (United States)

Loveless, Sian E.; Bloomfield, John P.; Ward, Robert S.; Hart, Alwyn J.; Davey, Ian R.; Lewis, Melinda A.

2018-03-01

Shale gas is considered by many to have the potential to provide the UK with greater energy security, economic growth and jobs. However, development of a shale gas industry is highly contentious due to environmental concerns including the risk of groundwater pollution. Evidence suggests that the vertical separation between exploited shale units and aquifers is an important factor in the risk to groundwater from shale gas exploitation. A methodology is presented to assess the vertical separation between different pairs of aquifers and shales that are present across England and Wales. The application of the method is then demonstrated for two of these pairs—the Cretaceous Chalk Group aquifer and the Upper Jurassic Kimmeridge Clay Formation, and the Triassic sandstone aquifer and the Carboniferous Bowland Shale Formation. Challenges in defining what might be considered criteria for `safe separation' between a shale gas formation and an overlying aquifer are discussed, in particular with respect to uncertainties in geological properties, aquifer extents and determination of socially acceptable risk levels. Modelled vertical separations suggest that the risk of aquifer contamination from shale exploration will vary greatly between shale-aquifer pairs and between regions and this will need to be considered carefully as part of the risk assessment and management for any shale gas development.

Instrumentation at pulsed neutron sources

International Nuclear Information System (INIS)

Carpenter, J.M.; Lander, G.H.; Windsor, C.G.

1984-01-01

Scientific investigations involving the use of neutron beams have been centered at reactor sources for the last 35 years. Recently, there has been considerable interest in using the neutrons produced by accelerator driven (pulsed) sources. Such installations are in operation in England, Japan, and the United States. In this article a brief survey is given of how the neutron beams are produced and how they can be optimized for neutron scattering experiments. A detailed description is then given of the various types of instruments that have been, or are planned, at pulsed sources. Numerous examples of the scientific results that are emerging are given. An attempt is made throughout the article to compare the scientific opportunities at pulsed sources with the proven performance of reactor installations, and some familiarity with the latter and the general field of neutron scattering is assumed. New areas are being opened up by pulsed sources, particularly with the intense epithermal neutron beams, which promise to be several orders of magnitude more intense than can be obtained from a thermal reactor

Operational analysis and comparative evaluation of embedded Z-Source inverters

DEFF Research Database (Denmark)

Blaabjerg, Frede; Gao, F.; Loh, P.C.

2008-01-01

) circuitry connected instead of the generic voltage source inverter (VSI) circuitry. Further proceeding on to the topological variation, parallel embedded Z-source inverters are presented with the detailed analysis of topological configuration and operational principles showing that they are the superior......This paper presents various embedded Z-source (EZ-source) inverters broadly classified as shunt or parallel embedded Z-source inverter. Being different from the traditional Z-source inverter, EZ-source inverters are constructed by inserting dc sources into the X-shaped impedance network so...... that the dc input current flows smoothly during the whole switching period unlike the traditional Z-source inverter. This feature is interesting when PV panels or fuel cells are assumed to power load since the continuous input current flow reduces control complexity of dc source and system design burden...

Distillation Calculation for the Separation of {sup 13}CH{sub 4} from LNG

Energy Technology Data Exchange (ETDEWEB)

Song, K.M.; Son, S.H.; Kim, K.S.; Lee, S.K. [Korea Electric Power Research Institute, Taejon (Korea)

2002-07-01

For the purpose of {sup 13}CH{sub 4} production from LNG, the theoretical number of stages and the number of distillation column required for the separation of {sup 13}CH{sub 4} from {sup 12}CH{sub 4}/{sup 13}CH{sub 4} mixture of containing 1%-{sup 13}CH{sub 4} are calculated. Assuming the ideal liquid mixture of containing 1%-{sup 13}CH{sub 4} are calculated. Assuming the ideal liquid mixture of {sup 12}CH{sub 4} and {sup 13}CH{sub 4}, the theoretical number of stages are calculated by smoker equation and FUG method. Using the correlation between the minimum theoretical number of stages and the optimum theoretical number of stages, the number of distillation groups is calculated. From this calculation, we know that 6 groups of distillation tower with 600 stages per one column are needed for the production of 90%-{sup 13}CH{sub 4}. (author). 5 refs., 5 figs., 4 tabs.

Development of a plutonium ceramic target for the MASHA separator

Energy Technology Data Exchange (ETDEWEB)

Shaughnessy, D.A.; Moody, K.J.; Kenneally, J.M.; Wild, J.F.; Stoyer, M.A.; Lougheed, R.W.; Yeremin, A.V.; Oganessian, Yu.Ts

2004-04-05

We are participating in the development of the target for the MASHA (Mass Analyzer of Super Heavy Atoms) on-line mass separator in Dubna. Along with recent upgrades of the U400 cyclotron, MASHA will provide for at least a ten-fold increase in the production- and-detection rate for element 114 atoms, and will allow us to measure their atomic masses precisely. The MASHA separator will employ a thick Pu ceramic target capable of tolerating temperatures in the vicinity of 2000 C without vaporizing the actinide compound. Reaction products will diffuse out of the target and will drift to an ECR ion source after which they will be transported through the separator and will impinge on a position-sensitive focal-plane detector array. Furthermore, operation of the MASHA hot target/ion source combination will provide chemical volatility information that will support our assignment of an atomic number of 114 to these nuclei. Taken together, these experiments on MASHA will allow us to make measurements that will cement our identification of element 114 and provide for future experiments in which the chemical properties of the heaviest elements are studied.

Development of a Plutonium Ceramic Target for the MASHA Separator

Science.gov (United States)

Shaughnessy, D. A.; Moody, K. J.; Kenneally, J. M.; Wild, J. F.; Stoyer, M. A.; Lougheed, R. W.; Yeremin, A. V.; Oganessian, Yu. Ts.

2004-04-01

We are participating in the development of the target for the MASHA (Mass Analyzer of Super Heavy Atoms) on-line mass separator in Dubna. Along with recent upgrades of the U400 cyclotron, MASHA will provide for at least a ten-fold increase in the production- and-detection rate for element 114 atoms, and will allow us to measure their atomic masses precisely. The MASHA separator will employ a thick Pu ceramic target capa- ble of tolerating temperatures in the vicinity of 2000 C without vaporizing the actinide compound. Reaction products will diffuse out of the target and will drift to an ECR ion source after which they will be transported through the separator and will impinge on a position-sensitive focal-plane detector array. Furthermore, operation of the MASHA hot target/ion source combination will provide chemical volatility information that will support our assignment of an atomic number of 114 to these nuclei. Taken together, these experiments on MASHA will allow us to make measurements that will cement our identification of element 114 and provide for future experiments in which the chemical properties of the heaviest elements are studied.

Development of a plutonium ceramic target for the MASHA separator

International Nuclear Information System (INIS)

Shaughnessy, D.A.; Moody, K.J.; Kenneally, J.M.; Wild, J.F.; Stoyer, M.A.; Lougheed, R.W.; Yeremin, A.V.; Oganessian, Yu.Ts.

2004-01-01

We are participating in the development of the target for the MASHA (Mass Analyzer of Super Heavy Atoms) on-line mass separator in Dubna. Along with recent upgrades of the U400 cyclotron, MASHA will provide for at least a ten-fold increase in the production- and-detection rate for element 114 atoms, and will allow us to measure their atomic masses precisely. The MASHA separator will employ a thick Pu ceramic target capable of tolerating temperatures in the vicinity of 2000 C without vaporizing the actinide compound. Reaction products will diffuse out of the target and will drift to an ECR ion source after which they will be transported through the separator and will impinge on a position-sensitive focal-plane detector array. Furthermore, operation of the MASHA hot target/ion source combination will provide chemical volatility information that will support our assignment of an atomic number of 114 to these nuclei. Taken together, these experiments on MASHA will allow us to make measurements that will cement our identification of element 114 and provide for future experiments in which the chemical properties of the heaviest elements are studied

Selected Hanford reactor and separations operating data for 1960--1964

Energy Technology Data Exchange (ETDEWEB)

Gydesen, S.P.

1992-09-01

The purpose of this letter report is to reconstruct from available information that data which can be used to develop daily reactor operating history for 1960--1964. The information needed for source team calculations (as determined by the Source Terms Task Leader) were extracted and included in this report. The data on the amount of uranium dissolved by the separations plants (expressed both as tons and as MW) is also included in this compilation.

Selected Hanford reactor and separations operating data for 1960--1964

International Nuclear Information System (INIS)

Gydesen, S.P.

1992-09-01

The purpose of this letter report is to reconstruct from available information that data which can be used to develop daily reactor operating history for 1960--1964. The information needed for source team calculations (as determined by the Source Terms Task Leader) were extracted and included in this report. The data on the amount of uranium dissolved by the separations plants (expressed both as tons and as MW) is also included in this compilation

Numerical investigation on flow behavior and energy separation in a micro-scale vortex tube

Directory of Open Access Journals (Sweden)

Rahbar Nader

2015-01-01

Full Text Available There are a few experimental and numerical studies on the behaviour of micro-scale vortex tubes. The intention of this work is to investigate the energy separation phenomenon in a micro-scale vortex tube by using the computational fluid dynamic. The flow is assumed as steady, turbulent, compressible ideal gas, and the shear-stress transport sst k-w is used for modeling of turbulence phenomenon. The results show that 3-D CFD simulation is more accurate than 2-D axisymmetric one. Moreover, optimum cold-mass ratios to maximize the refrigeration-power and isentropicefficiency are evaluated. The results of static temperature, velocity magnitude and pressure distributions show that the temperature-separation in the micro-scale vortex tube is a function of kinetic-energy variation and air-expansion in the radial direction.

Blind instantaneous noisy mixture separation with best interference-plus-noise rejection

Czech Academy of Sciences Publication Activity Database

Koldovský, Zbyněk; Tichavský, Petr

2007-01-01

Roč. 2007, Č. 4666 (2007), s. 730-737 ISSN 0302-9743. [Independent Component Analysis and Signal Separation. Londyn, 09.09.2007-12.09.2007] R&D Projects: GA MŠk 1M0572 Grant - others:GA ČR(CZ) GP102/07/P384 Program:GP Institutional research plan: CEZ:AV0Z10750506 Keywords : blind source separation * independent component analysis Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 0.402, year: 2005

Chromatographic Separation of Vitamin E Enantiomers

Directory of Open Access Journals (Sweden)

Ju-Yen Fu

2017-02-01

Full Text Available Vitamin E is recognized as an essential vitamin since its discovery in 1922. Most vegetable oils contain a mixture of tocopherols and tocotrienols in the vitamin E composition. Structurally, tocopherols and tocotrienols share a similar chromanol ring and a side chain at the C-2 position. Owing to the three chiral centers in tocopherols, they can appear as eight different stereoisomers. Plant sources of tocopherol are naturally occurring in the form of RRR while synthetic tocopherols are usually in the form of all-racemic mixture. Similarly, with only one chiral center, natural tocotrienols occur as the R-isoform. In this review, we aim to discuss a few chromatographic methods that had been used to separate the stereoisomers of tocopherols and tocotrienols. These methods include high performance liquid chromatography, gas chromatography and combination of both. The review will focus on method development including selection of chiral columns, detection method and choice of elution solvent in the context of separation efficiency, resolution and chiral purity. The applications for separation of enantiomers in vitamin E will also be discussed especially in terms of the distinctive biological potency among the stereoisoforms.

Factors Moderating Children's Adjustment to Parental Separation: Findings from a Community Study in England

Science.gov (United States)

Cheng, Helen; Dunn, Judy; O'Connor, Thomas G.; Golding, Jean

2006-01-01

Research findings show that there is marked variability in children's response to parental separation, but few studies identify the sources of this variation. This prospective longitudinal study examines the factors modifying children's adjustment to parental separation in a community sample of 5,635 families in England. Children's…

Is BTZ a separate superselection sector of CTMG?

Energy Technology Data Exchange (ETDEWEB)

Deser, S., E-mail: deser@brandeis.ed [Physics Department, Brandeis University, Waltham, MA 02454 (United States); Lauritsen Laboratory, California Institute of Technology, Pasadena, CA 91125 (United States); Franklin, J., E-mail: jfrankli@reed.ed [Reed College, Portland, OR 97202 (United States)

2010-10-18

We exhibit exact solutions of (positive) matter coupled to original 'wrong G-sign' cosmological TMG. They all evolve to conical singularity, rather than to black hole - here negative mass - BTZ. This provides evidence that the latter constitute a separate 'superselection' sector, one that unlike in GR, is not reachable by physical sources.

Free-form analysis of the cosmological evolution of radio sources

International Nuclear Information System (INIS)

Robertson, J.G.

1980-01-01

This paper extends an iterative scheme for calculation of free-form evolution functions able to reconcile observed radio source counts with the standard General Relativistic cosmological models. It is assumed that the luminosity dependence of the evolution consists of a gradual turn-on of evolution above a certain luminosity. No particular functional form is assumed for the redshift dependence of the evolution (i.e. it is free-form). The extension concerns the use of the luminosity distribution to supply an effective luminosity function, thus overcoming a problem of consistency at the high-luminosity end of the luminosity function, where the evolution function has to be known. This method also guarantees that the correct average redshifts will be predicted where they are known observationally at high flux densities. The new iterative scheme has been applied to the source counts at 408 MHz from the Molonglo Cross telescope, using the Einstein-de Sitter cosmology and a recent determination of the luminosity distribution for sources of S 408 > 10 Jy. (author)

On Distributions of Emission Sources and Speed-of-Sound in Proton-Proton (Proton-Antiproton Collisions

Directory of Open Access Journals (Sweden)

Li-Na Gao

2015-01-01

Full Text Available The revised (three-source Landau hydrodynamic model is used in this paper to study the (pseudorapidity distributions of charged particles produced in proton-proton and proton-antiproton collisions at high energies. The central source is assumed to contribute with a Gaussian function which covers the rapidity distribution region as wide as possible. The target and projectile sources are assumed to emit isotropically particles in their respective rest frames. The model calculations obtained with a Monte Carlo method are fitted to the experimental data over an energy range from 0.2 to 13 TeV. The values of the squared speed-of-sound parameter in different collisions are then extracted from the width of the rapidity distributions.

Sparse Bayesian Learning for Nonstationary Data Sources

Science.gov (United States)

Fujimaki, Ryohei; Yairi, Takehisa; Machida, Kazuo

This paper proposes an online Sparse Bayesian Learning (SBL) algorithm for modeling nonstationary data sources. Although most learning algorithms implicitly assume that a data source does not change over time (stationary), one in the real world usually does due to such various factors as dynamically changing environments, device degradation, sudden failures, etc (nonstationary). The proposed algorithm can be made useable for stationary online SBL by setting time decay parameters to zero, and as such it can be interpreted as a single unified framework for online SBL for use with stationary and nonstationary data sources. Tests both on four types of benchmark problems and on actual stock price data have shown it to perform well.

Scaling of rotation and isotope separation in a vacuum-arc centrifuge

International Nuclear Information System (INIS)

Prasad, R.R.; Krishnan, M.

1987-01-01

Scaling is described of rotation, plasma column size and separation in a vacuum-arc centrifuge. The vacuum-arc centrifuge is a magnetized, fulled ionized, quasineutral column of plasma. The source of plasma is a vacuum-arc discharge between a negatively biased cathode and a grounded mesh anode. Rigid-body rotation, induced by the J x B force, causes radial, centrifugal separation of isotopes in the plasma column. Salient features of a fluid model that provides an understanding of rotation and the concomitant isotope separation in the vacuum-arc centrifuge are described. Scaling of rotation and plasma column size is found be consistent with the model. Measurements of isotope separation, also found to agree with the predictions of the model, are presented. Results of a parametric analysis of isotope separation in such a vacuum-arc centrifuge, using the fluid model and the observed scaling laws, are described. An analysis of the energy cost of separation of the vacuum-arc centrifuge shows that it typically requires only 70 keV/separated atom. (orig.)

Separations technology development to support accelerator-driven transmutation concepts

International Nuclear Information System (INIS)

Venneri, F.; Arthur, E.; Bowman, C.

1996-01-01

This is the final report of a one-year Laboratory-Directed Research and Development (LDRD) Project at the Los Alamos National Laboratory (LANL). This project investigated separations technology development needed for accelerator-driven transmutation technology (ADTT) concepts, particularly those associated with plutonium disposition (accelerator-based conversion, ABC) and high-level radioactive waste transmutation (accelerator transmutation of waste, ATW). Specific focus areas included separations needed for preparation of feeds to ABC and ATW systems, for example from spent reactor fuel sources, those required within an ABC/ATW system for material recycle and recovery of key long-lived radionuclides for further transmutation, and those required for reuse and cleanup of molten fluoride salts. The project also featured beginning experimental development in areas associated with a small molten-salt test loop and exploratory centrifugal separations systems

Can components in distortion-product otoacoustic emissions be separated?

DEFF Research Database (Denmark)

Christensen, Anders Tornvig; W. Purcell, David; Christensen, Flemming

2012-01-01

Otoacoustic emissions are signals emitted from the cochlea, either spontaneously or evoked by stimuli. Measured with an acoustic probe sealed in the ear-canal, they reveal information about a part of the mechanism of hearing that is otherwise inaccessible. Outer hair cells in the cochlea work...... to improve hearing sensitivity by means of nonlinear amplification, which produces distortion. In the measurement of otoacoustic emissions, two tones can be delivered to the cochlea to invoke this nonlinearity and elicit the distortion-product otoacoustic emission (DPOAE). DPOAEs arise mainly from two...... spatially separated generation mechanisms, thus making interpretation of DPOAE measurements complicated. In this study, we test whether or not source separation by group delays is equivalent to separation by time delays – either result is equally interesting to understand given the complexity of the cochlea...

Linear and Differential Ion Mobility Separations of Middle-Down Proteoforms

DEFF Research Database (Denmark)

Garabedian, Alyssa; Baird, Matthew A; Porter, Jacob

2018-01-01

. Separations using traveling-wave (TWIMS) and/or involving various time scales and electrospray ionization source conditions are similar (with lower resolution for TWIMS), showing the transferability of results across linear IMS instruments. The linear IMS and FAIMS dimensions are substantially orthogonal...

Separation of Hydrogen Isotopes by Palladium Alloy Membranes Separator

International Nuclear Information System (INIS)

Jiangfeng, S.; Deli, L.; Yifu, X.; Congxian, L.; Zhiyong, H.

2007-01-01

Full text of publication follows: Separation of hydrogen isotope with palladium alloy membranes is one of the promising methods for hydrogen isotope separation. It has several advantages, such as high separation efficiency, smaller tritium inventory, simple separation device, ect. Limited by the manufacture of membrane and cost of gas transportation pump, this method is still at the stage of conceptual study. The relationship between separation factors and temperatures, feed gas components, split ratios have not been researched in detail, and the calculated results of cascade separation have not been validated with experimental data. In this thesis, a palladium alloy membrane separator was designed to further study its separation performance between H 2 and D 2 . The separation factor of the single stage was affected by the temperature, the feed gas component, the split ratio and the gas flow rate, etc. The experimental results showed that the H 2 -D 2 separation factor decreased with the increasing of temperature. On the temperature from 573 K to 773 K, when the feed rate was 5 L/min, the separation factor of 66.2%H 2 - 33.8%D 2 decreased from 2.09 to 1.85 when the split ratio was 0.1 and from 1.74 to 1.52 when the split ratio was 0.2.The separation factor also decreased with the increasing of split ratio. At 573 K and the feed rate of 5 L/min, the separation factor of 15.0%H 2 and 85.0%D 2 decreased from 2.43 to 1.35 with the increasing of split ratio from 0.050 to 0.534,and for 66.2%H 2 -33.8%D 2 , the separation factor decreased from 2.87 to 1.30 with the increasing of split ratio from 0.050 to 0.688. When the separation factor was the biggest, the flow rate of feed gas was in a perfect value. To gain a best separation performance, perfect flow rate, lower temperature and reflux ratio should be chosen. (authors)

5 CFR 5201.102 - Designation of separate agency components.

Science.gov (United States)

2010-01-01

... ETHICAL CONDUCT FOR EMPLOYEES OF THE DEPARTMENT OF LABOR § 5201.102 Designation of separate agency...) Office of Labor-Management Standards. (c) Definitions—(1) Remainder of the Department means employees in... prohibited source of gifts for MSHA employees. The contractor is not regulated by and has no business...

Study of the feasibility of distributed cathodic arc as a plasma source for development of the technology for plasma separation of SNF and radioactive wastes

Energy Technology Data Exchange (ETDEWEB)

Amirov, R. Kh.; Vorona, N. A.; Gavrikov, A. V.; Liziakin, G. D.; Polistchook, V. P.; Samoylov, I. S.; Smirnov, V. P.; Usmanov, R. A., E-mail: ravus46@yandex.ru; Yartsev, I. M. [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation)

2015-12-15

One of the key problems in the development of plasma separation technology is designing a plasma source which uses condensed spent nuclear fuel (SNF) or nuclear wastes as a raw material. This paper covers the experimental study of the evaporation and ionization of model materials (gadolinium, niobium oxide, and titanium oxide). For these purposes, a vacuum arc with a heated cathode on the studied material was initiated and its parameters in different regimes were studied. During the experiment, the cathode temperature, arc current, arc voltage, and plasma radiation spectra were measured, and also probe measurements were carried out. It was found that the increase in the cathode heating power leads to the decrease in the arc voltage (to 3 V). This fact makes it possible to reduce the electron energy and achieve singly ionized plasma with a high degree of ionization to fulfill one of the requirements for plasma separation of SNF. This finding is supported by the analysis of the plasma radiation spectrum and the results of the probe diagnostics.

The Chandra Source Catalog 2.0: Estimating Source Fluxes

Science.gov (United States)

Primini, Francis Anthony; Allen, Christopher E.; Miller, Joseph; Anderson, Craig S.; Budynkiewicz, Jamie A.; Burke, Douglas; Chen, Judy C.; Civano, Francesca Maria; D'Abrusco, Raffaele; Doe, Stephen M.; Evans, Ian N.; Evans, Janet D.; Fabbiano, Giuseppina; Gibbs, Danny G., II; Glotfelty, Kenny J.; Graessle, Dale E.; Grier, John D.; Hain, Roger; Hall, Diane M.; Harbo, Peter N.; Houck, John C.; Lauer, Jennifer L.; Laurino, Omar; Lee, Nicholas P.; Martínez-Galarza, Juan Rafael; McCollough, Michael L.; McDowell, Jonathan C.; McLaughlin, Warren; Morgan, Douglas L.; Mossman, Amy E.; Nguyen, Dan T.; Nichols, Joy S.; Nowak, Michael A.; Paxson, Charles; Plummer, David A.; Rots, Arnold H.; Siemiginowska, Aneta; Sundheim, Beth A.; Tibbetts, Michael; Van Stone, David W.; Zografou, Panagoula

2018-01-01

The Second Chandra Source Catalog (CSC2.0) will provide information on approximately 316,000 point or compact extended x-ray sources, derived from over 10,000 ACIS and HRC-I imaging observations available in the public archive at the end of 2014. As in the previous catalog release (CSC1.1), fluxes for these sources will be determined separately from source detection, using a Bayesian formalism that accounts for background, spatial resolution effects, and contamination from nearby sources. However, the CSC2.0 procedure differs from that used in CSC1.1 in three important aspects. First, for sources in crowded regions in which photometric apertures overlap, fluxes are determined jointly, using an extension of the CSC1.1 algorithm, as discussed in Primini & Kashyap (2014ApJ...796…24P). Second, an MCMC procedure is used to estimate marginalized posterior probability distributions for source fluxes. Finally, for sources observed in multiple observations, a Bayesian Blocks algorithm (Scargle, et al. 2013ApJ...764..167S) is used to group observations into blocks of constant source flux.In this poster we present details of the CSC2.0 photometry algorithms and illustrate their performance in actual CSC2.0 datasets.This work has been supported by NASA under contract NAS 8-03060 to the Smithsonian Astrophysical Observatory for operation of the Chandra X-ray Center.

Séparation Aveugle de Mélanges Convolutifs de Sources

OpenAIRE

Boumaraf , Hakim

2005-01-01

In this thesis, Blind Source Separation (BSS) of Convolutive Mixtures of Sources is addressed. For separating audio mixtures, we have developed new methods for cases without noise and with noise in propagation environment. The method for case without noise is based on joint diagonalization of spectral matrices and exploit the non stationarity of signals. We have proposed two techniques in order to solve permutation problem. The second method where an additive noise is present, is based on max...

Collisional tearing in a field-reversed sheet pinch assuming nonparallel propagation

International Nuclear Information System (INIS)

Quest, K.B.; Coroniti, F.V.

1985-01-01

We examine the linear stability properties of the collisional tearing mode in a reversed-field sheet pinch assuming that the wave vector is not parallel to B, where B is the equilibrium magnetic field. We show that pressure balance in the direction of the equilibrium current requires a nonzero perturbed current component deltaJ/sub z/ that is driven toward tyhe center of the pinch. At the center of the pinch, deltaJ/sub z/ goes to zero, and momentum is balanced by coupling to the ion-acoustic mode. In order to achieve current closure, a large perturbed field-aligned current is generated that is strongly localized about the dissipative tearing layer. The relation of this work to the collisionless case is discussed

Project of computer program for designing the steel with the assumed CCT diagram

OpenAIRE

S. Malara; J. Trzaska; L.A. Dobrzański

2007-01-01

Purpose: The aim of this paper was developing a project of computer aided method for designing the chemicalcomposition of steel with the assumed CCT diagram.Design/methodology/approach: The purpose has been achieved in four stages. At the first stage characteristicpoints of CCT diagram have been determined. At the second stage neural networks have been developed, andnext CCT diagram terms of similarity have been worked out- at the third one. In the last one steel chemicalcomposition optimizat...

Impaired neurogenesis of the dentate gyrus is associated with pattern separation deficits: A computational study.

Science.gov (United States)

Faghihi, Faramarz; Moustafa, Ahmed A

2016-09-01

The separation of input patterns received from the entorhinal cortex (EC) by the dentate gyrus (DG) is a well-known critical step of information processing in the hippocampus. Although the role of interneurons in separation pattern efficiency of the DG has been theoretically known, the balance of neurogenesis of excitatory neurons and interneurons as well as its potential role in information processing in the DG is not fully understood. In this work, we study separation efficiency of the DG for different rates of neurogenesis of interneurons and excitatory neurons using a novel computational model in which we assume an increase in the synaptic efficacy between excitatory neurons and interneurons and then its decay over time. Information processing in the EC and DG was simulated as information flow in a two layer feed-forward neural network. The neurogenesis rate was modeled as the percentage of new born neurons added to the neuronal population in each time bin. The results show an important role of an optimal neurogenesis rate of interneurons and excitatory neurons in the DG in efficient separation of inputs from the EC in pattern separation tasks. The model predicts that any deviation of the optimal values of neurogenesis rates leads to different decreased levels of the separation deficits of the DG which influences its function to encode memory.

Radioactive source recovery program responses to neutron source emergencies

International Nuclear Information System (INIS)

Dinehart, S.M.; Hatler, V.A.; Gray, D.W.; Guillen, A.D.

1997-01-01

Recovery of neutron sources containing Pu 239 and Be is currently taking place at Los Alamos National Laboratory. The program was initiated in 1979 by the Department of Energy (DOE) to dismantle and recover sources owned primarily by universities and the Department of Defense. Since the inception of this program, Los Alamos has dismantled and recovered more than 1000 sources. The dismantlement and recovery process involves the removal of source cladding and the chemical separation of the source materials to eliminate neutron emissions. While this program continues for the disposal of 239 Pu/Be sources, there is currently no avenue for the disposition of any sources other than those containing Pu 239 . Increasingly, there have been demands from agencies both inside and outside the Federal Government and from the public to dispose of unwanted sources containing 238 Pu/Be and 241 Am/Be. DOE is attempting to establish a formal program to recover these sources and is working closely with the Nuclear Regulatory Commission (NRC) on a proposed Memorandum of Understanding to formalize an Acceptance Program. In the absence of a formal program to handle 238 Pu/Be and 241 Am/Be neutron sources, Los Alamos has responded to several emergency requests to receive and recover sources that have been determined to be a threat to public health and safety. This presentation will: (1) review the established 239 Pu neutron source recovery program at Los Alamos, (2) detail plans for a more extensive neutron source disposal program, and (3) focus on recent emergency responses

Spectroscopic measurements of an H- ion source discharge

International Nuclear Information System (INIS)

Keller, R.; Smith, H.V. Jr.

1985-01-01

Spectral emission lines from an H - Penning surface-plasma source (SPS), the 4X source, are examined in the visible and near ultraviolet. Electron distribution temperatures are deduced from integral line-strength measurements. These temperatures are surprisingly low, about 0.5 eV. Electron density values of about 1.5 x 10 14 cm -3 and H-atom energies between 2 and 2.6 eV are determined from the measured Balmer-line profiles. Assuming the H - energy is identical to the H-atom energy, an emittance limit of 0.006 π x cm x mrad is deduced for this source with a 5.4-mm aperture

Configuration of separability and tests for multipartite entanglement in bell-type experiments.

Science.gov (United States)

Nagata, Koji; Koashi, Masato; Imoto, Nobuyuki

2002-12-23

We derive tight quadratic inequalities for all kinds of hybrid separable-inseparable n-particle density operators on an arbitrary dimensional space. This methodology enables us to derive a tight quadratic inequality as tests for full n-partite entanglement in various Bell-type correlation experiments on the systems that may not be identified as a collection of qubits, e.g., those involving photons measured by incomplete detectors. It is also proved that when the two measured observables are assumed to precisely anticommute, a stronger quadratic inequality can be used as a witness of full n-partite entanglement.

Automated Assume-Guarantee Reasoning for Omega-Regular Systems and Specifications

Science.gov (United States)

Chaki, Sagar; Gurfinkel, Arie

2010-01-01

We develop a learning-based automated Assume-Guarantee (AG) reasoning framework for verifying omega-regular properties of concurrent systems. We study the applicability of non-circular (AGNC) and circular (AG-C) AG proof rules in the context of systems with infinite behaviors. In particular, we show that AG-NC is incomplete when assumptions are restricted to strictly infinite behaviors, while AG-C remains complete. We present a general formalization, called LAG, of the learning based automated AG paradigm. We show how existing approaches for automated AG reasoning are special instances of LAG.We develop two learning algorithms for a class of systems, called infinite regular systems, that combine finite and infinite behaviors. We show that for infinity-regular systems, both AG-NC and AG-C are sound and complete. Finally, we show how to instantiate LAG to do automated AG reasoning for infinite regular, and omega-regular, systems using both AG-NC and AG-C as proof rules

Novel, Ceramic Membrane System For Hydrogen Separation

Energy Technology Data Exchange (ETDEWEB)

Elangovan, S.

2012-12-31

Separation of hydrogen from coal gas represents one of the most promising ways to produce alternative sources of fuel. Ceramatec, teamed with CoorsTek and Sandia National Laboratories has developed materials technology for a pressure driven, high temperature proton-electron mixed conducting membrane system to remove hydrogen from the syngas. This system separates high purity hydrogen and isolates high pressure CO{sub 2} as the retentate, which is amenable to low cost capture and transport to storage sites. The team demonstrated a highly efficient, pressure-driven hydrogen separation membrane to generate high purity hydrogen from syngas using a novel ceramic-ceramic composite membrane. Recognizing the benefits and limitations of present membrane systems, the all-ceramic system has been developed to address the key technical challenges related to materials performance under actual operating conditions, while retaining the advantages of thermal and process compatibility offered by the ceramic membranes. The feasibility of the concept has already been demonstrated at Ceramatec. This project developed advanced materials composition for potential integration with water gas shift rectors to maximize the hydrogenproduction.

Separations Technology for Clean Water and Energy

Energy Technology Data Exchange (ETDEWEB)

Jarvinen, Gordon D [Los Alamos National Laboratory

2012-06-22

Providing clean water and energy for about nine billion people on the earth by midcentury is a daunting challenge. Major investments in efficiency of energy and water use and deployment of all economical energy sources will be needed. Separations technology has an important role to play in producing both clean energy and water. Some examples are carbon dioxide capture and sequestration from fossil energy power plants and advanced nuclear fuel cycle scemes. Membrane separations systems are under development to improve the economics of carbon capture that would be required at a huge scale. For nuclear fuel cycles, only the PUREX liquid-liquid extraction process has been deployed on a large scale to recover uranium and plutonium from used fuel. Most current R and D on separations technology for used nuclear fuel focuses on ehhancements to a PUREX-type plant to recover the minor actinides (neptunium, americiu, and curium) and more efficiently disposition the fission products. Are there more efficient routes to recycle the actinides on the horizon? Some new approaches and barriers to development will be briefly reviewed.

238Pu sources for cardiac pacemakers. II. Control

International Nuclear Information System (INIS)

Pottier, R.; Merigot, S.

1976-01-01

The method and the apparatus used for thermal (power) and radioactive control of radioisotopic sources for pacemakers are briefly described. The cybernetic system is also presented, which assumes almost automatically the monitoring of control, mechanical and electronic works, data processing, the measurements and computations, and the works related to quality control [fr

Estimating the number of sources in a noisy convolutive mixture using BIC

DEFF Research Database (Denmark)

Olsson, Rasmus Kongsgaard; Hansen, Lars Kai

2004-01-01

The number of source signals in a noisy convolutive mixture is determined based on the exact log-likelihoods of the candidate models. In (Olsson and Hansen, 2004), a novel probabilistic blind source separator was introduced that is based solely on the time-varying second-order statistics of the s......The number of source signals in a noisy convolutive mixture is determined based on the exact log-likelihoods of the candidate models. In (Olsson and Hansen, 2004), a novel probabilistic blind source separator was introduced that is based solely on the time-varying second-order statistics...

Separation of CO{sub 2}/N{sub 2} by means of a carbon membrane

Energy Technology Data Exchange (ETDEWEB)

Wall, Y.; Braun, G. [Cologne University of Applied Sciences, Cologne (Germany); Kaltenborn, N.; Voigt, I. [Fraunhofer Institute for Ceramic Technologies and Systems, IKTS, Hermsdorf (Germany); Brunner, G. [Hamburg University of Technology (TUHH), Hamburg (Germany)

2012-03-15

The permeation and separation performance of an ultramicroporous carbon membrane for separation of CO{sub 2}/N{sub 2} mixtures were investigated. The experiments were conducted using the steady-state measurement method with pure gases (dead-end mode) and a CO{sub 2}/N{sub 2} gas mixture (20/80 mol.-%) (cross-flow mode) in the temperature range from 293 K to 363 K and at feed pressures of up to 1.4 MPa and atmospheric pressure on the permeate side. The membrane exhibited a selectivity of about 25 and permeability of about 500 Barrer for CO{sub 2} in the mixture with N{sub 2}. The single-gas measurements do not reflect the membrane performance correctly. An adsorption-selective effect is assumed to be the main separation mechanism. Moreover, membrane-aging effects causing blocking due to pore constrictions through adsorption were observed. These pore constrictions lower the permeability, but they raise the selectivity. Operation at high temperatures leads to a reduction of aging effects. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

A comparative table of various energy sources

International Nuclear Information System (INIS)

Anon.

1976-01-01

This table provides wide informations on the technological facets of various sources of primary energy. One of the outstanding features of this table is that it exposes and compares various technological problems involved in the energy conversion processes. The primary energy sources treated here are the solar energy (heat and light are treated separately), the geothermal energy, coal (gasification and liquefaction are treated separately), oil, natural gas, oceano-energy (tidal energy, temperature difference, and wave energy are treated separately), organic wastes, oil shale, tar sand, hydraulic power, wind power, biomass, uranium, thorium, and deuterium and lithium. On the other hand, the comparisons are made in three major items, i.e. charactersitics as natural resources, conversion or refinement to secondary energy sources, and economical characteristics. The first item includes the estimated and recognized amount of deposits, easiness of mining, storage, and transportation, and cleanliness and safety. As for conversion characteristics, the easiness, controlability, efficiency, cleanliness, and safety of various conversion processes are compared. Finally, as for economical problems, cost comparisons are made for gathering or mining those resources, including required energy input, man power, required facilities, and site conditions. (Aoki, K.)

Very low-energy conversion electron detection (VLECED) system at the isocele on-line isotope separator, Orsay

International Nuclear Information System (INIS)

Kilcher, P.; Sauvage, J.; Munsch, J.; Obert, J.; Caruette, A.; Ferro, A.; Boissier, G.; Fournet-Fayas, J.; Ducourtieux, M.; Landois, G.

1988-01-01

A system designed and installed at the on-line isotope separator ISOCELE II allows the high resolution detection of low-energy conversion electrons (down to 1 keV) emitted by mass separated radioactive sources: the use of a special tape transport permits both the slowing down of the incoming beam of radioactive ions up to a collection point and the acceleration of the electrons emitted by the collected sources brought to a flat magnetic spectrograph. Typical spectra so obtained are presented

High-efficiency thermal ionization sources for mass spectrometry

International Nuclear Information System (INIS)

Olivares, Jose A.

1996-01-01

A version of the thermal ionization cavity (TIC) source developed specifically for use in mass spectrometry is presented. The performance of this ion source has been characterized extensively both with the use of an isotope separator and a quadrupole mass spectrometer. A detailed description of the TIC source for mass spectrometry is given along with the performance characteristics observed

ESOL facility for the generation and radiochemical separation of short half-life fission products

International Nuclear Information System (INIS)

Gehrke, R.J.; Meikrantz, D.H.; Baker, J.D.; Anderl, R.A.; Novick, V.J.; Greenwood, R.C.

1988-01-01

A facility has been developed at the Idaho National Engineering Laboratory (INEL) for the generation and rapid radiochemical separation of short half-life mixed fission products. This facility, referred to as the Idaho Elemental Separation On Line (ESOL), consists of electro-plated sources of spontaneously fissioning 252 Cf with a helium jet transport arrangement to continuously deliver short half-life, mixed fission products to the radiochemistry laboratory for rapid, computer controlled, radiochemical separations. 18 refs., 13 figs

CHANDRA OBSERVATIONS OF A 1.9 kpc SEPARATION DOUBLE X-RAY SOURCE IN A CANDIDATE DUAL ACTIVE GALACTIC NUCLEUS GALAXY AT z = 0.16

International Nuclear Information System (INIS)

Comerford, Julia M.; Pooley, David; Gerke, Brian F.; Madejski, Greg M.

2011-01-01

We report Chandra observations of a double X-ray source in the z = 0.1569 galaxy SDSS J171544.05+600835.7. The galaxy was initially identified as a dual active galactic nucleus (AGN) candidate based on the double-peaked [O III] λ5007 emission lines, with a line-of-sight velocity separation of 350 km s -1 , in its Sloan Digital Sky Survey spectrum. We used the Kast Spectrograph at Lick Observatory to obtain two long-slit spectra of the galaxy at two different position angles, which reveal that the two Type 2 AGN emission components have not only a velocity offset, but also a projected spatial offset of 1.9 h -1 70 kpc on the sky. Chandra/ACIS observations of two X-ray sources with the same spatial offset and orientation as the optical emission suggest that the galaxy most likely contains Compton-thick dual AGNs, although the observations could also be explained by AGN jets. Deeper X-ray observations that reveal Fe K lines, if present, would distinguish between the two scenarios. The observations of a double X-ray source in SDSS J171544.05+600835.7 are a proof of concept for a new, systematic detection method that selects promising dual AGN candidates from ground-based spectroscopy that exhibits both velocity and spatial offsets in the AGN emission features.

The isotope separator on-line at the INS-SF cyclotron

International Nuclear Information System (INIS)

Yonehara, H.; Kawakami, H.; Tanaka, J.; Omata, K.; Shida, Y.

1981-02-01

The Isotope Separator On-Line at the SF Cyclotron has been improved. Some details of improvements are described on the target-ion source, rapid extraction with aluminized tape, tape transport system and data aquisition. The performance of the improved SF-ISOL is discussed. (author)

Isotope and machine sources for food irradiation

International Nuclear Information System (INIS)

Balcazar G, M.

1992-05-01

Artificial radioactive sources as Co-60 and Cs- 137 are produced by bombarding Co-59 with neutrons in a nuclear reactor and by chemical separation of spent nuclear fuel respectively. Both radioactive sources emit very high frequency electromagnetic radiation called y-rays. This highly penetrating radiation is employed for preservation of food. Each y-ray emitted from a radioactive source transports energy from the source to the irradiated food. Penetration of y-rays and their intensity depend on y-energy. Inside this study the advantages and disadvantages of both sources are compared. (Author)

Isotope and machine sources for food irradiation

Energy Technology Data Exchange (ETDEWEB)

Balcazar G, M

1992-05-15

Artificial radioactive sources as Co-60 and Cs- 137 are produced by bombarding Co-59 with neutrons in a nuclear reactor and by chemical separation of spent nuclear fuel respectively. Both radioactive sources emit very high frequency electromagnetic radiation called y-rays. This highly penetrating radiation is employed for preservation of food. Each y-ray emitted from a radioactive source transports energy from the source to the irradiated food. Penetration of y-rays and their intensity depend on y-energy. Inside this study the advantages and disadvantages of both sources are compared. (Author)

A two-dimensional transient analytical solution for a ponded ditch drainage system under the influence of source/sink

Science.gov (United States)

Sarmah, Ratan; Tiwari, Shubham

2018-03-01

An analytical solution is developed for predicting two-dimensional transient seepage into ditch drainage network receiving water from a non-uniform steady ponding field from the surface of the soil under the influence of source/sink in the flow domain. The flow domain is assumed to be saturated, homogeneous and anisotropic in nature and have finite extends in horizontal and vertical directions. The drains are assumed to be standing vertical and penetrating up to impervious layer. The water levels in the drains are unequal and invariant with time. The flow field is also assumed to be under the continuous influence of time-space dependent arbitrary source/sink term. The correctness of the proposed model is checked by developing a numerical code and also with the existing analytical solution for the simplified case. The study highlights the significance of source/sink influence in the subsurface flow. With the imposition of the source and sink term in the flow domain, the pathline and travel time of water particles started deviating from their original position and above that the side and top discharge to the drains were also observed to have a strong influence of the source/sink terms. The travel time and pathline of water particles are also observed to have a dependency on the height of water in the ditches and on the location of source/sink activation area.

Liquid-phase separation with the rotational particle separator

NARCIS (Netherlands)

Kemenade, van H.P.; Mondt, E.; Hendriks, A.J.A.M.; Verbeek, P.H.J.

2003-01-01

Recently, the rotational particle separator (RPS) was introduced as a new technique for separating solid and/or liquid particles of 0.1 m and larger from gases. In this patented technique the principles of centrifugation are exploited to enhance separation of small-sized phases and particulate

Optimization of light source parameters in the photodynamic therapy of heterogeneous prostate

International Nuclear Information System (INIS)

Li Jun; Altschuler, Martin D; Hahn, Stephen M; Zhu, Timothy C

2008-01-01

The three-dimensional (3D) heterogeneous distributions of optical properties in a patient prostate can now be measured in vivo. Such data can be used to obtain a more accurate light-fluence kernel. (For specified sources and points, the kernel gives the fluence delivered to a point by a source of unit strength.) In turn, the kernel can be used to solve the inverse problem that determines the source strengths needed to deliver a prescribed photodynamic therapy (PDT) dose (or light-fluence) distribution within the prostate (assuming uniform drug concentration). We have developed and tested computational procedures to use the new heterogeneous data to optimize delivered light-fluence. New problems arise, however, in quickly obtaining an accurate kernel following the insertion of interstitial light sources and data acquisition. (1) The light-fluence kernel must be calculated in 3D and separately for each light source, which increases kernel size. (2) An accurate kernel for light scattering in a heterogeneous medium requires ray tracing and volume partitioning, thus significant calculation time. To address these problems, two different kernels were examined and compared for speed of creation and accuracy of dose. Kernels derived more quickly involve simpler algorithms. Our goal is to achieve optimal dose planning with patient-specific heterogeneous optical data applied through accurate kernels, all within clinical times. The optimization process is restricted to accepting the given (interstitially inserted) sources, and determining the best source strengths with which to obtain a prescribed dose. The Cimmino feasibility algorithm is used for this purpose. The dose distribution and source weights obtained for each kernel are analyzed. In clinical use, optimization will also be performed prior to source insertion to obtain initial source positions, source lengths and source weights, but with the assumption of homogeneous optical properties. For this reason, we compare the

Exotic pets are new allergenic sources: allergy to iguana.

Science.gov (United States)

San Miguel-Moncín, M M; Pineda, F; Río, C; Alonso, R; Tella, R; Cisteró-Bahima, A

2006-01-01

Although furry animals are known sources of respiratory allergy, scaly animals are assumed not to be allergenic. Exotic animals such as iguanas are becoming increasingly common pets. Nevertheless, these animals are not suspected to be allergenic. We present the case of a 42-year-old woman suffering from allergic rhinoconjunctivitis and asthma caused by a pet iguana. Clear IgE-sensitization and respiratory allergy to iguana scales is demonstrated, suggesting that scaly pets should be taken into account as possible allergenic sources.

Separation of hepatic iron and fat by dual-source dual-energy computed tomography based on material decomposition: an animal study.

Directory of Open Access Journals (Sweden)

Jing Ma

Full Text Available OBJECTIVE: To explore the feasibility of dual-source dual-energy computed tomography (DSDECT for hepatic iron and fat separation in vivo. MATERIALS AND METHODS: All of the procedures in this study were approved by the Research Animal Resource Center of Shanghai Ruijin Hospital. Sixty rats that underwent DECT scanning were divided into the normal group, fatty liver group, liver iron group, and coexisting liver iron and fat group, according to Prussian blue and HE staining. The data for each group were reconstructed and post-processed by an iron-specific, three-material decomposition algorithm. The iron enhancement value and the virtual non-iron contrast value, which indicated overloaded liver iron and residual liver tissue, respectively, were measured. Spearman's correlation and one-way analysis of variance (ANOVA were performed, respectively, to analyze statistically the correlations with the histopathological results and differences among groups. RESULTS: The iron enhancement values were positively correlated with the iron pathology grading (r = 0.729, p<0.001. Virtual non-iron contrast (VNC values were negatively correlated with the fat pathology grading (r = -0.642,p<0.0001. Different groups showed significantly different iron enhancement values and VNC values (F = 25.308,p<0.001; F = 10.911, p<0.001, respectively. Among the groups, significant differences in iron enhancement values were only observed between the iron-present and iron-absent groups, and differences in VNC values were only observed between the fat-present and fat-absent groups. CONCLUSION: Separation of hepatic iron and fat by dual energy material decomposition in vivo was feasible, even when they coexisted.

Real-time adaptive concepts in acoustics blind signal separation and multichannel echo cancellation

CERN Document Server

Schobben, Daniel W E

2001-01-01

Blind Signal Separation (BSS) deals with recovering (filtered versions of) source signals from an observed mixture thereof. The term `blind' relates to the fact that there are no reference signals for the source signals and also that the mixing system is unknown. This book presents a new method for blind signal separation, which is developed to work on microphone signals. Acoustic Echo Cancellation (AEC) is a well-known technique to suppress the echo that a microphone picks up from a loudspeaker in the same room. Such acoustic feedback occurs for example in hands-free telephony and can lead to a perceived loud tone. For an application such as a voice-controlled television, a stereo AEC is required to suppress the contribution of the stereo loudspeaker setup. A generalized AEC is presented that is suited for multi-channel operation. New algorithms for Blind Signal Separation and multi-channel Acoustic Echo Cancellation are presented. A background is given in array signal processing methods, adaptive filter the...

Earthquake spectra and near-source attenuation in the Cascadia subduction zone

Science.gov (United States)

Gomberg, J.; Creager, K.; Sweet, J.; Vidale, J.; Ghosh, A.; Hotovec, A.

2012-05-01

Models of seismic source displacement spectra are flat from zero to some corner frequency, fc, regardless of source type. At higher frequencies spectral models decay as f-1 for slow events and as f-2 for fast earthquakes. We show that at least in Cascadia, wave propagation effects likely control spectral decay rates above ˜2 Hz. We use seismograms from multiple small-aperture arrays to estimate the spectral decay rates of near-source spectra of 37 small `events' and find strong correlation between source location and decay rate. The decay rates (1) vary overall by an amount in excess of that inferred to distinguish slow sources from fast earthquakes, (2) are indistinguishable for sources separated by a few tens of km or less, and (3) separate into two populations that correlate with propagation through and outside a low-velocity zone imaged tomographically. We find that some events repeat, as is characteristic of low-frequency earthquakes (LFEs), but have spectra similar to those of non-repeating earthquakes. We also find no correlation between spectral decay rates and rates of ambient tremor activity. These results suggest that earthquakes near the plate boundary, at least in Cascadia, do not distinctly separate into `slow' and `fast' classes, and correctly accounting for propagation effects is necessary to characterize sources.

Modulation Schemes of Multi-phase Three-Level Z-Source Inverters

DEFF Research Database (Denmark)

Gao, F.; Loh, P.C.; Blaabjerg, Frede

2007-01-01

different modulation requirement and output performance. For clearly illustrating the detailed modulation process, time domain analysis instead of the traditional multi-dimensional space vector demonstration is assumed which reveals the right way to insert shoot-through durations in the switching sequence...... with minimal commutation count. Lastly, the theoretical findings are verified in Matlab/PLECS simulation and experimentally using constructed laboratory prototypes.......This paper investigates the modulation schemes of three-level multiphase Z-source inverters with either two Z-source networks or single Z-source network connected between the dc sources and inverter circuitry. With the proper offset added for achieving both desired four-leg operation and optimized...

Combining inter-source seismic interferometry and source-receiver interferometry for deep local imaging

NARCIS (Netherlands)

Liu, Y.; Arntsen, B.; Wapenaar, C.P.A.; Van der Neut, J.R.

2014-01-01

The virtual source method has been applied successfully to retrieve the impulse response between pairs of receivers in the subsurface. This method is further improved by an updown separation prior to the crosscorrelation to suppress the reflections from the overburden and the free surface. In a

Separations systems data base: a users' manual. Revision I

International Nuclear Information System (INIS)

Roddy, J.W.; McDowell, W.J.

1981-01-01

A separations systems data base (SEPSYS), designed specifically for the retrieval of information needed in chemical separations problems (i.e., how to perform a given separation under given conditions), is described. Included are descriptions of the basic methods of searching and retrieving information from the data base, the procedure for entering records into the data base, a listing of additional references concerning the computer information process, and an example of a typical record. The initial entries are concerned primarily with liquid-liquid extraction and liquid-solid ion exchange methods for metal ions and salts; however, the data base is constructed so that almost any separation process can be accommodated. Each record is indexed with information provided under the following fields: author; title; publication source; data of publication; organization sponsoring the work; brief abstract of the work; abstract number if the work has been so referenced, and/or abstractors initials; type of separation system used (e.g., flotation); specific or generic name of the separation agent used (e.g., acetylacetone); list of substances separated (e.g., gold, copper); qualitative description of the supporting medium or matrix containing the substances before separation (e.g., nitrate); type of literature where the record was printed (e.g., book); and type of information that the article contains. Each of these fields may be searched independently of the others (or in combination), and the last six fields contain specific key words that are listed in the report. Definitions are provided for the 36 information terms

Combination of Complex-Based and Magnitude-Based Multiecho Water-Fat Separation for Accurate Quantification of Fat-Fraction

Science.gov (United States)

Yu, Huanzhou; Shimakawa, Ann; Hines, Catherine D. G.; McKenzie, Charles A.; Hamilton, Gavin; Sirlin, Claude B.; Brittain, Jean H.; Reeder, Scott B.

2011-01-01

Multipoint water–fat separation techniques rely on different water–fat phase shifts generated at multiple echo times to decompose water and fat. Therefore, these methods require complex source images and allow unambiguous separation of water and fat signals. However, complex-based water–fat separation methods are sensitive to phase errors in the source images, which may lead to clinically important errors. An alternative approach to quantify fat is through “magnitude-based” methods that acquire multiecho magnitude images. Magnitude-based methods are insensitive to phase errors, but cannot estimate fat-fraction greater than 50%. In this work, we introduce a water–fat separation approach that combines the strengths of both complex and magnitude reconstruction algorithms. A magnitude-based reconstruction is applied after complex-based water–fat separation to removes the effect of phase errors. The results from the two reconstructions are then combined. We demonstrate that using this hybrid method, 0–100% fat-fraction can be estimated with improved accuracy at low fat-fractions. PMID:21695724

Steam-water separator

International Nuclear Information System (INIS)

Modrak, T.M.; Curtis, R.W.

1978-01-01

The steam-water separator connected downstream of a steam generator consists of a vertical centrifugal separator with swirl blades between two concentric pipes and a cyclone separator located above. The water separated in the cyclone separator is collected in the inner tube of the centrifugal separator which is closed at the bottom. This design allows the overall height of the separator to be reduced. (DG) [de

Advanced system for separation of rare-earth fission products

International Nuclear Information System (INIS)

Baker, J.D.; Gehrke, R.J.; Greenwood, R.C.; Meikrantz, D.H.

1982-01-01

A microprocessor-controlled radiochemical separation system has been further advanced to separate individual rare-earth elements from mixed fission products in times of a few minutes. The system was composed of an automated chemistry system fed by two approximately 300 μg 252 Cf sources coupled directly by a He-jet to transport the fission products. Chemical separations were performed using two high performance liquid chromatography columns coupled in series. The first column separated the rare-earth group by extraction chromatography using dihexyldiethylcarbamoylmethylphosphonate (DHDECMP) adsorbed on Vydac C 8 resin. The second column isolated the individual rare-earth elements by cation exchange chromatography using Aminex A-9 resin with α-hydroxyisobutyric acid (α-HIBA) as the eluent. Significant results, which have been obtained to date with this advanced system, are the identification of several new neutron-rich rare-earth isotopes including 155 Pm (T=48+-4 s) and 163 Gd (T=68+-3 s). In addition, a half-life of 41+-4 s is reported for 160 Eu. (author)

Development of Separation Materials Containing Palladium for Hydrogen Isotopes Separation

International Nuclear Information System (INIS)

Deng Xiaojun; Luo Deli; Qian Xiaojing

2010-01-01

Displacement chromatography (DC) is a ascendant technique for hydrogen isotopes separation. The performance of separation materials is a key factor to determine the separation effect of DC. At present,kinds of materials are researched, including palladium materials and non-palladium materials. It is hardly replaceable because of its excellent separation performance, although palladium is expensive. The theory of hydrogen isotopes separation using DC was introduced at a brief manner, while several palladium separation materials were expatiated in detail(Pd/K, Pd-Al 2 O 3 , Pd-Pt alloy). Development direction of separation materials for DC was forecasted elementarily. (authors)

Inductive Sensor Performance in Partial Discharges and Noise Separation by Means of Spectral Power Ratios

Directory of Open Access Journals (Sweden)

Jorge Alfredo Ardila-Rey

2014-02-01

Full Text Available Partial discharge (PD detection is a standardized technique to qualify electrical insulation in machines and power cables. Several techniques that analyze the waveform of the pulses have been proposed to discriminate noise from PD activity. Among them, spectral power ratio representation shows great flexibility in the separation of the sources of PD. Mapping spectral power ratios in two-dimensional plots leads to clusters of points which group pulses with similar characteristics. The position in the map depends on the nature of the partial discharge, the setup and the frequency response of the sensors. If these clusters are clearly separated, the subsequent task of identifying the source of the discharge is straightforward so the distance between clusters can be a figure of merit to suggest the best option for PD recognition. In this paper, two inductive sensors with different frequency responses to pulsed signals, a high frequency current transformer and an inductive loop sensor, are analyzed to test their performance in detecting and separating the sources of partial discharges.

Efficiency of an on-line isotope separator system employing cooled and NaCl-loaded He-jet methods

International Nuclear Information System (INIS)

Aeystoe, J.; Rantala, V.; Valli, K.; Hillebrand, S.; Kortelahti, M.; Eskola, K.; Raunemaa, T.

1976-01-01

A pure helium-jet at liquid nitrogen temperature coupled to a Nielsen type ion source, and a NaCl-loaded helium-jet coupled to a hollow-cathode ion source have been investigated as means to connect a cyclotron target chamber on-line to a mass separator. Technical details and performances of some critical parts of the system are described. Total separation efficiencies measured under various experimental conditions for several nuclides vary between 0.01 and 1.0%. (Auth.)

Recent developments in optical detection methods for microchip separations.

Science.gov (United States)

Götz, Sebastian; Karst, Uwe

2007-01-01

This paper summarizes the features and performances of optical detection systems currently applied in order to monitor separations on microchip devices. Fluorescence detection, which delivers very high sensitivity and selectivity, is still the most widely applied method of detection. Instruments utilizing laser-induced fluorescence (LIF) and lamp-based fluorescence along with recent applications of light-emitting diodes (LED) as excitation sources are also covered in this paper. Since chemiluminescence detection can be achieved using extremely simple devices which no longer require light sources and optical components for focusing and collimation, interesting approaches based on this technique are presented, too. Although UV/vis absorbance is a detection method that is commonly used in standard desktop electrophoresis and liquid chromatography instruments, it has not yet reached the same level of popularity for microchip applications. Current applications of UV/vis absorbance detection to microchip separations and innovative approaches that increase sensitivity are described. This article, which contains 85 references, focuses on developments and applications published within the last three years, points out exciting new approaches, and provides future perspectives on this field.

Beam Dynamics Simulations of the REX-ISOLDE A/q-separator

CERN Document Server

Fraser, M A; Wenander, F

2014-01-01

The REX-ISOLDE A=q-separator selects the radioactive species of interest from the background of residual gas ions coming from the EBIS ion source. In the context of the HIE-ISOLDE upgrade, including the implementation of a multi-harmonic buncher and an upgraded EBIS, the separator and the beam line between the EBIS and RFQ, which we will call the Low Energy Beam Transfer (LEBT) line, has been simulated by tracking particles through the field maps of each active element using the TRACK [4] code. The simulations were benchmarked with a COSY-1 model that was improved to take into account the fringe fields of the electrostatic quadrupoles, electrostatic deflector and magnetic bender; the model can be used to tune and optimise the separator with higher-order effects taken into account. In this note the beam dynamics simulations are documented and the transverse and longitudinal acceptance of the separator line studied to provide design constraints for the EBIS upgrade.

Detection, Source Location, and Analysis of Volcano Infrasound

Science.gov (United States)

McKee, Kathleen F.

in volcanic environments. The fumarolic jet noise was found to have a sustained, low amplitude signal with a spectral peak between 7-10 Hz. From thermal imagery we measure the jet temperature ( 260 °C) and estimate the jet diameter ( 2.5 m). From the estimated jet diameter, an assumed Strouhal number of 0.19, and the jet noise peak frequency, we estimated the jet velocity to be 79 - 132 m/s. We used published gas data to then estimate the volatile flux at 160 - 270 kg/s (14,000 - 23,000 t/d). These estimates are typically difficult to obtain in volcanic environments, but provide valuable information on the eruption. At regional and global length scales we use infrasound arrays to detect signals and determine their source back-azimuths. A ground coupled airwave (GCA) occurs when an incident acoustic pressure wave encounters the Earth's surface and part of the energy of the wave is transferred to the ground. GCAs are commonly observed from sources such as volcanic eruptions, bolides, meteors, and explosions. They have been observed to have retrograde particle motion. When recorded on collocated seismo-acoustic sensors, the phase between the infrasound and seismic signals is 90°. If the sensors are separated wind noise is usually incoherent and an additional phase is added due to the sensor separation. We utilized the additional phase and the characteristic particle motion to determine a unique back-azimuth solution to an acoustic source. The additional phase will be different depending on the direction from which a wave arrives. Our technique was tested using synthetic seismo-acoustic data from a coupled Earth-atmosphere 3D finite difference code and then applied to two well-constrained datasets: Mount St. Helens, USA, and Mount Pagan, Commonwealth of the Northern Mariana Islands Volcanoes. The results from our method are within <1° - 5° of the actual and traditional infrasound array processing determined back-azimuths. Ours is a new method to detect and determine

Bayesian source term determination with unknown covariance of measurements

Science.gov (United States)

Belal, Alkomiet; Tichý, Ondřej; Šmídl, Václav

2017-04-01

Determination of a source term of release of a hazardous material into the atmosphere is a very important task for emergency response. We are concerned with the problem of estimation of the source term in the conventional linear inverse problem, y = Mx, where the relationship between the vector of observations y is described using the source-receptor-sensitivity (SRS) matrix M and the unknown source term x. Since the system is typically ill-conditioned, the problem is recast as an optimization problem minR,B(y - Mx)TR-1(y - Mx) + xTB-1x. The first term minimizes the error of the measurements with covariance matrix R, and the second term is a regularization of the source term. There are different types of regularization arising for different choices of matrices R and B, for example, Tikhonov regularization assumes covariance matrix B as the identity matrix multiplied by scalar parameter. In this contribution, we adopt a Bayesian approach to make inference on the unknown source term x as well as unknown R and B. We assume prior on x to be a Gaussian with zero mean and unknown diagonal covariance matrix B. The covariance matrix of the likelihood R is also unknown. We consider two potential choices of the structure of the matrix R. First is the diagonal matrix and the second is a locally correlated structure using information on topology of the measuring network. Since the inference of the model is intractable, iterative variational Bayes algorithm is used for simultaneous estimation of all model parameters. The practical usefulness of our contribution is demonstrated on an application of the resulting algorithm to real data from the European Tracer Experiment (ETEX). This research is supported by EEA/Norwegian Financial Mechanism under project MSMT-28477/2014 Source-Term Determination of Radionuclide Releases by Inverse Atmospheric Dispersion Modelling (STRADI).

Distinctive Correspondence Between Separable Visual Attention Functions and Intrinsic Brain Networks.

Science.gov (United States)

Ruiz-Rizzo, Adriana L; Neitzel, Julia; Müller, Hermann J; Sorg, Christian; Finke, Kathrin

2018-01-01

Separable visual attention functions are assumed to rely on distinct but interacting neural mechanisms. Bundesen's "theory of visual attention" (TVA) allows the mathematical estimation of independent parameters that characterize individuals' visual attentional capacity (i.e., visual processing speed and visual short-term memory storage capacity) and selectivity functions (i.e., top-down control and spatial laterality). However, it is unclear whether these parameters distinctively map onto different brain networks obtained from intrinsic functional connectivity, which organizes slowly fluctuating ongoing brain activity. In our study, 31 demographically homogeneous healthy young participants performed whole- and partial-report tasks and underwent resting-state functional magnetic resonance imaging (rs-fMRI). Report accuracy was modeled using TVA to estimate, individually, the four TVA parameters. Networks encompassing cortical areas relevant for visual attention were derived from independent component analysis of rs-fMRI data: visual, executive control, right and left frontoparietal, and ventral and dorsal attention networks. Two TVA parameters were mapped on particular functional networks. First, participants with higher (vs. lower) visual processing speed showed lower functional connectivity within the ventral attention network. Second, participants with more (vs. less) efficient top-down control showed higher functional connectivity within the dorsal attention network and lower functional connectivity within the visual network. Additionally, higher performance was associated with higher functional connectivity between networks: specifically, between the ventral attention and right frontoparietal networks for visual processing speed, and between the visual and executive control networks for top-down control. The higher inter-network functional connectivity was related to lower intra-network connectivity. These results demonstrate that separable visual attention

Distinctive Correspondence Between Separable Visual Attention Functions and Intrinsic Brain Networks

Science.gov (United States)

Ruiz-Rizzo, Adriana L.; Neitzel, Julia; Müller, Hermann J.; Sorg, Christian; Finke, Kathrin

2018-01-01

Separable visual attention functions are assumed to rely on distinct but interacting neural mechanisms. Bundesen's “theory of visual attention” (TVA) allows the mathematical estimation of independent parameters that characterize individuals' visual attentional capacity (i.e., visual processing speed and visual short-term memory storage capacity) and selectivity functions (i.e., top-down control and spatial laterality). However, it is unclear whether these parameters distinctively map onto different brain networks obtained from intrinsic functional connectivity, which organizes slowly fluctuating ongoing brain activity. In our study, 31 demographically homogeneous healthy young participants performed whole- and partial-report tasks and underwent resting-state functional magnetic resonance imaging (rs-fMRI). Report accuracy was modeled using TVA to estimate, individually, the four TVA parameters. Networks encompassing cortical areas relevant for visual attention were derived from independent component analysis of rs-fMRI data: visual, executive control, right and left frontoparietal, and ventral and dorsal attention networks. Two TVA parameters were mapped on particular functional networks. First, participants with higher (vs. lower) visual processing speed showed lower functional connectivity within the ventral attention network. Second, participants with more (vs. less) efficient top-down control showed higher functional connectivity within the dorsal attention network and lower functional connectivity within the visual network. Additionally, higher performance was associated with higher functional connectivity between networks: specifically, between the ventral attention and right frontoparietal networks for visual processing speed, and between the visual and executive control networks for top-down control. The higher inter-network functional connectivity was related to lower intra-network connectivity. These results demonstrate that separable visual attention

Distinctive Correspondence Between Separable Visual Attention Functions and Intrinsic Brain Networks

Directory of Open Access Journals (Sweden)

Adriana L. Ruiz-Rizzo

2018-03-01

Full Text Available Separable visual attention functions are assumed to rely on distinct but interacting neural mechanisms. Bundesen's “theory of visual attention” (TVA allows the mathematical estimation of independent parameters that characterize individuals' visual attentional capacity (i.e., visual processing speed and visual short-term memory storage capacity and selectivity functions (i.e., top-down control and spatial laterality. However, it is unclear whether these parameters distinctively map onto different brain networks obtained from intrinsic functional connectivity, which organizes slowly fluctuating ongoing brain activity. In our study, 31 demographically homogeneous healthy young participants performed whole- and partial-report tasks and underwent resting-state functional magnetic resonance imaging (rs-fMRI. Report accuracy was modeled using TVA to estimate, individually, the four TVA parameters. Networks encompassing cortical areas relevant for visual attention were derived from independent component analysis of rs-fMRI data: visual, executive control, right and left frontoparietal, and ventral and dorsal attention networks. Two TVA parameters were mapped on particular functional networks. First, participants with higher (vs. lower visual processing speed showed lower functional connectivity within the ventral attention network. Second, participants with more (vs. less efficient top-down control showed higher functional connectivity within the dorsal attention network and lower functional connectivity within the visual network. Additionally, higher performance was associated with higher functional connectivity between networks: specifically, between the ventral attention and right frontoparietal networks for visual processing speed, and between the visual and executive control networks for top-down control. The higher inter-network functional connectivity was related to lower intra-network connectivity. These results demonstrate that separable

Numerical Simulation of Dispersion from Urban Greenhouse Gas Sources

Science.gov (United States)

Nottrott, Anders; Tan, Sze; He, Yonggang; Winkler, Renato

2017-04-01

Cities are characterized by complex topography, inhomogeneous turbulence, and variable pollutant source distributions. These features create a scale separation between local sources and urban scale emissions estimates known as the Grey-Zone. Modern computational fluid dynamics (CFD) techniques provide a quasi-deterministic, physically based toolset to bridge the scale separation gap between source level dynamics, local measurements, and urban scale emissions inventories. CFD has the capability to represent complex building topography and capture detailed 3D turbulence fields in the urban boundary layer. This presentation discusses the application of OpenFOAM to urban CFD simulations of natural gas leaks in cities. OpenFOAM is an open source software for advanced numerical simulation of engineering and environmental fluid flows. When combined with free or low cost computer aided drawing and GIS, OpenFOAM generates a detailed, 3D representation of urban wind fields. OpenFOAM was applied to model scalar emissions from various components of the natural gas distribution system, to study the impact of urban meteorology on mobile greenhouse gas measurements. The numerical experiments demonstrate that CH4 concentration profiles are highly sensitive to the relative location of emission sources and buildings. Sources separated by distances of 5-10 meters showed significant differences in vertical dispersion of plumes, due to building wake effects. The OpenFOAM flow fields were combined with an inverse, stochastic dispersion model to quantify and visualize the sensitivity of point sensors to upwind sources in various built environments. The Boussinesq approximation was applied to investigate the effects of canopy layer temperature gradients and convection on sensor footprints.

Research on preventive technologies for bed-separation water hazard in China coal mines

Science.gov (United States)

Gui, Herong; Tong, Shijie; Qiu, Weizhong; Lin, Manli

2018-03-01

Bed-separation water is one of the major water hazards in coal mines. Targeted researches on the preventive technologies are of paramount importance to safe mining. This article studied the restrictive effect of geological and mining factors, such as lithological properties of roof strata, coal seam inclination, water source to bed separations, roof management method, dimensions of mining working face, and mining progress, on the formation of bed-separation water hazard. The key techniques to prevent bed-separation water-related accidents include interception, diversion, destructing the buffer layer, grouting and backfilling, etc. The operation and efficiency of each technique are corroborated in field engineering cases. The results of this study will offer reference to countries with similar mining conditions in the researches on bed-separation water burst and hazard control in coal mines.

A Two-Stage MMSE Beamformer for Underdetermined Signal Separation

Czech Academy of Sciences Publication Activity Database

Koldovský, Zbyněk; Tichavský, Petr; Phan, A. H.; Cichocki, A.

2013-01-01

Roč. 20, č. 12 (2013), s. 1227-1230 ISSN 1070-9908 Grant - others:GA ČR(CZ) GAP103/11/1947 Program:GA Institutional support: RVO:67985556 Keywords : beamforming * underdetermined mixtures * blind source separation Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 1.639, year: 2013 http://library.utia.cas.cz/separaty/2014/SI/koldovsky-0424112.pdf

Dipping-interface mapping using mode-separated Rayleigh waves

Science.gov (United States)

Luo, Y.; Xia, J.; Xu, Y.; Zeng, C.; Miller, R.D.; Liu, Q.

2009-01-01

Multichannel analysis of surface waves (MASW) method is a non-invasive geophysical technique that uses the dispersive characteristic of Rayleigh waves to estimate a vertical shear (S)-wave velocity profile. A pseudo-2D S-wave velocity section is constructed by aligning 1D S-wave velocity profiles at the midpoint of each receiver spread that are contoured using a spatial interpolation scheme. The horizontal resolution of the section is therefore most influenced by the receiver spread length and the source interval. Based on the assumption that a dipping-layer model can be regarded as stepped flat layers, high-resolution linear Radon transform (LRT) has been proposed to image Rayleigh-wave dispersive energy and separate modes of Rayleigh waves from a multichannel record. With the mode-separation technique, therefore, a dispersion curve that possesses satisfactory accuracy can be calculated using a pair of consecutive traces within a mode-separated shot gather. In this study, using synthetic models containing a dipping layer with a slope of 5, 10, 15, 20, or 30 degrees and a real-world example, we assess the ability of using high-resolution LRT to image and separate fundamental-mode Rayleigh waves from raw surface-wave data and accuracy of dispersion curves generated by a pair of consecutive traces within a mode-separated shot gather. Results of synthetic and real-world examples demonstrate that a dipping interface with a slope smaller than 15 degrees can be successfully mapped by separated fundamental waves using high-resolution LRT. ?? Birkh??user Verlag, Basel 2009.

Method for separating mono- and di-octylphenyl phosphoric acid esters

International Nuclear Information System (INIS)

Arnold, W.D. Jr.

1977-01-01

A method for separating mono-octylphenyl phosphoric acid ester and di-octylphenyl phosphoric acid ester from a mixture thereof comprises reacting the ester mixture with a source of lithium or sodium ions to form a mixture of the phosphate salts; contacting the salt mixture with an organic solvent which causes the dioctylphenyl phosphate salt to be dissolved in the organic solvent phase and the mono-octylphenyl phosphate salt to exist in a solid phase; separating the phases; recovering the phosphate salts from their respective phases; and acidifying the recovered salts to form the original phosphoric acid esters

Blind Component Separation in Wavelet Space: Application to CMB Analysis

Directory of Open Access Journals (Sweden)

J. Delabrouille

2005-09-01

Full Text Available It is a recurrent issue in astronomical data analysis that observations are incomplete maps with missing patches or intentionally masked parts. In addition, many astrophysical emissions are nonstationary processes over the sky. All these effects impair data processing techniques which work in the Fourier domain. Spectral matching ICA (SMICA is a source separation method based on spectral matching in Fourier space designed for the separation of diffuse astrophysical emissions in cosmic microwave background observations. This paper proposes an extension of SMICA to the wavelet domain and demonstrates the effectiveness of wavelet-based statistics for dealing with gaps in the data.

Integrating Carbon Nanotubes into Microfluidic Chip for Separating Biochemical Compounds

DEFF Research Database (Denmark)

Chen, Miaoxiang Max; Mogensen, Klaus Bo; Bøggild, Peter

2012-01-01

We present a new type of device to separate biochemical compounds wherein carbon nanotubes (CNTs) are integrated as chromatographic stationary phase. The CNTs were directly grown on the bottom of microfluidic channels on Si/SiO2 substrates by chemical vapor deposition (CVD). Acetylene was used...... as carbon source and Ni was employed as catalyst. For electrokinetic separations, higher electrical field strength is usually required; therefore, the CNTs were constructed in pillar-array-form by patterning the catalyst layer. Electrical field strength of 2.0 kV/cm has been realized, which is more than one...

Solid-phase extraction and separation procedure for trace aluminum in water samples and its determination by high-resolution continuum source flame atomic absorption spectrometry (HR-CS FAAS).

Science.gov (United States)

Ciftci, Harun; Er, Cigdem

2013-03-01

In the present study, a separation/preconcentration procedure for determination of aluminum in water samples has been developed by using a new atomic absorption spectrometer concept with a high-intensity xenon short-arc lamp as continuum radiation source, a high-resolution double-echelle monochromator, and a charge-coupled device array detector. Sample solution pH, sample volume, flow rate of sample solution, volume, and concentration of eluent for solid-phase extraction of Al chelates with 4-[(dicyanomethyl)diazenyl] benzoic acid on polymeric resin (Duolite XAD-761) have been investigated. The adsorbed aluminum on resin was eluted with 5 mL of 2 mol L(-1) HNO(3) and its concentration was determined by high-resolution continuum source flame atomic absorption spectrometry (HR-CS FAAS). Under the optimal conditions, limit of detection obtained with HR-CS FAAS and Line Source FAAS (LS-FAAS) were 0.49 μg L(-1) and 3.91 μg L(-1), respectively. The accuracy of the procedure was confirmed by analyzing certified materials (NIST SRM 1643e, Trace elements in water) and spiked real samples. The developed procedure was successfully applied to water samples.

Production of radioactive ion beams and resonance ionization spectroscopy with the laser ion source at on-line isotope separator ISOLDE

International Nuclear Information System (INIS)

Fedosseev, V.N.; )

2005-01-01

Full text: The resonance ionisation laser ion source (RILIS) of the ISOLDE on-line isotope separation facility at CERN is based on the method of laser step-wise resonance ionisation of atoms in a hot metal cavity. Using the system of dye lasers pumped by copper vapour lasers the ion beams of many different metallic elements have been produced at ISOLDE with an ionization efficiency of up to 27%. The high selectivity of the resonance ionization is an important asset for the study of short-lived nuclides produced in targets bombarded by the proton beam of the CERN Booster accelerator. Radioactive ion beams of Be, Mg, Al, Mn, Ni, Cu, Zn, Ga, Ag, Cd, In, Sn, Sb, Tb, Yb, Tl, Pb and Bi have been generated with the RILIS. Setting the RILIS laser in the narrow line-width mode provides conditions for a high-resolution study of hyperfine structure and isotopic shifts of atomic lines for short-lived isotopes. The isomer selective ionization of Cu, Ag and Pb isotopes has been achieved by appropriate tuning of laser wavelengths

Fission-nuclide concentrations of ambient aerosol separated by size

International Nuclear Information System (INIS)

Csepregi, T.; Kovacs, L.; Maschek, I.; Szterjopulos, K.

1984-01-01

Examinations were carried on the radionuclides in aerosol deposited on filters of an air-conditioning plant with high air flow rate. For nuclide concentration of ambient air qualitative and quantitative analyses were made by gamma spectrometry. Methods have been developed for sample preparation, size fractionation by sedimentation technique and measurement of air flow. The collected aerosol particles was separated into five size fractions from 1 to 5 μm and the aerosol fractions were analysed. The mass/size distribution of the particles processed by sedimentation has been compared with that of the ambient aerosol separated by a slot impactor Hungarian type. Because the aggregation caused by the resuspensationtechnique would be assumed, electronmicrophotos were made on processed and unprocessed aerosols. On the basis of them the particle aggregation may be negligible. Otherwise, the derivation of concentration needs to know the exact air volume. For this aim the technical parameters of the aerodynamic system have also been measured in two different ways. The paper reports on the size dependence of fission products originating from the present global late fallout for a two years monitoring period. The results are compared with the daily beta activity concentration of aerosol samples taken by an other sampling unit. (Author)

Localized Ambient Solidity Separation Algorithm Based Computer User Segmentation

Science.gov (United States)

Sun, Xiao; Zhang, Tongda; Chai, Yueting; Liu, Yi

2015-01-01

Most of popular clustering methods typically have some strong assumptions of the dataset. For example, the k-means implicitly assumes that all clusters come from spherical Gaussian distributions which have different means but the same covariance. However, when dealing with datasets that have diverse distribution shapes or high dimensionality, these assumptions might not be valid anymore. In order to overcome this weakness, we proposed a new clustering algorithm named localized ambient solidity separation (LASS) algorithm, using a new isolation criterion called centroid distance. Compared with other density based isolation criteria, our proposed centroid distance isolation criterion addresses the problem caused by high dimensionality and varying density. The experiment on a designed two-dimensional benchmark dataset shows that our proposed LASS algorithm not only inherits the advantage of the original dissimilarity increments clustering method to separate naturally isolated clusters but also can identify the clusters which are adjacent, overlapping, and under background noise. Finally, we compared our LASS algorithm with the dissimilarity increments clustering method on a massive computer user dataset with over two million records that contains demographic and behaviors information. The results show that LASS algorithm works extremely well on this computer user dataset and can gain more knowledge from it. PMID:26221133

SEPARATION OF THE INTER- AND INTRA-PARTICLE POROSITY IN IMAGES OF POWDER COMPACTS

Directory of Open Access Journals (Sweden)

Jacques Lacaze

2011-05-01

Full Text Available Powder metallurgy is a highly developed and cheap method of manufacturing reliable materials, either metallic, ceramic or composite. This process was used to make green compacts of iron powders with a high porosity level. This study is part of a project aimed at describing the relationships between mechanical properties and morphological features of such compacts, with particular attention paid to the shape of the grains and the compaction pressure. In this report, a method is proposed to separate the intra grain porosity from the cavities located between particles. The approach is based on the covariogram of images obtained from the surface of the compacts by means of a laser roughometer. To achieve this separation, a model of the structure is proposed which assumes that the distributions of the grains and of the intra-particle cavities are random and independent. Each distribution is characterized by two parameters. A satisfactory agreement is obtained between experimental and calculated covariograms after identification of these parameters.

OpenMC In Situ Source Convergence Detection

Energy Technology Data Exchange (ETDEWEB)

Aldrich, Garrett Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Univ. of California, Davis, CA (United States); Dutta, Soumya [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); The Ohio State Univ., Columbus, OH (United States); Woodring, Jonathan Lee [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-05-07

We designed and implemented an in situ version of particle source convergence for the OpenMC particle transport simulator. OpenMC is a Monte Carlo based-particle simulator for neutron criticality calculations. For the transport simulation to be accurate, source particles must converge on a spatial distribution. Typically, convergence is obtained by iterating the simulation by a user-settable, fixed number of steps, and it is assumed that convergence is achieved. We instead implement a method to detect convergence, using the stochastic oscillator for identifying convergence of source particles based on their accumulated Shannon Entropy. Using our in situ convergence detection, we are able to detect and begin tallying results for the full simulation once the proper source distribution has been confirmed. Our method ensures that the simulation is not started too early, by a user setting too optimistic parameters, or too late, by setting too conservative a parameter.

Fictional Separation Logic

DEFF Research Database (Denmark)

Jensen, Jonas Buhrkal; Birkedal, Lars

2012-01-01

, separation means physical separation. In this paper, we introduce \\emph{fictional separation logic}, which includes more general forms of fictional separating conjunctions P * Q, where "*" does not require physical separation, but may also be used in situations where the memory resources described by P and Q...