Gap-filling meteorological variables with Empirical Orthogonal Functions
Graf, Alexander
2017-04-01
Gap-filling or modelling surface-atmosphere fluxes critically depends on an, ideally continuous, availability of their meteorological driver variables, such as e.g. air temperature, humidity, radiation, wind speed and precipitation. Unlike for eddy-covariance-based fluxes, data gaps are not unavoidable for these measurements. Nevertheless, missing or erroneous data can occur in practice due to instrument or power failures, disturbance, and temporary sensor or station dismounting for e.g. agricultural management or maintenance. If stations with similar measurements are available nearby, using their data for imputation (i.e. estimating missing data) either directly, after an elevation correction or via linear regression, is usually preferred over linear interpolation or monthly mean diurnal cycles. The popular implementation of regional networks of (partly low-cost) stations increases both, the need and the potential, for such neighbour-based imputation methods. For repeated satellite imagery, Beckers and Rixen (2003) suggested an imputation method based on empirical orthogonal functions (EOFs). While exploiting the same linear relations between time series at different observation points as regression, it is able to use information from all observation points to simultaneously estimate missing data at all observation points, provided that never all observations are missing at the same time. Briefly, the method uses the ability of the first few EOFs of a data matrix to reconstruct a noise-reduced version of this matrix; iterating missing data points from an initial guess (the column-wise averages) to an optimal version determined by cross-validation. The poster presents and discusses lessons learned from adapting and applying this methodology to station data. Several years of 10-minute averages of air temperature, pressure and humidity, incoming shortwave, longwave and photosynthetically active radiation, wind speed and precipitation, measured by a regional (70 km by
Liu, X.; Wang, M.
2016-02-01
For coastal and inland waters, complete (in spatial) and frequent satellite measurements are important in order to monitor and understand coastal biological and ecological processes and phenomena, such as diurnal variations. High-frequency images of the water diffuse attenuation coefficient at the wavelength of 490 nm (Kd(490)) derived from the Korean Geostationary Ocean Color Imager (GOCI) provide a unique opportunity to study diurnal variation of the water turbidity in coastal regions of the Bohai Sea, Yellow Sea, and East China Sea. However, there are lots of missing pixels in the original GOCI-derived Kd(490) images due to clouds and various other reasons. Data Interpolating Empirical Orthogonal Function (DINEOF) is a method to reconstruct missing data in geophysical datasets based on Empirical Orthogonal Function (EOF). In this study, the DINEOF is applied to GOCI-derived Kd(490) data in the Yangtze River mouth and the Yellow River mouth regions, the DINEOF reconstructed Kd(490) data are used to fill in the missing pixels, and the spatial patterns and temporal functions of the first three EOF modes are also used to investigate the sub-diurnal variation due to the tidal forcing. In addition, DINEOF method is also applied to the Visible Infrared Imaging Radiometer Suite (VIIRS) on board the Suomi National Polar-orbiting Partnership (SNPP) satellite to reconstruct missing pixels in the daily Kd(490) and chlorophyll-a concentration images, and some application examples in the Chesapeake Bay and the Gulf of Mexico will be presented.
Levitan, Nathaniel; Gross, Barry
2016-10-01
New, high-resolution aerosol products are required in urban areas to improve the spatial coverage of the products, in terms of both resolution and retrieval frequency. These new products will improve our understanding of the spatial variability of aerosols in urban areas and will be useful in the detection of localized aerosol emissions. Urban aerosol retrieval is challenging for existing algorithms because of the high spatial variability of the surface reflectance, indicating the need for improved urban surface reflectance models. This problem can be stated in the language of novelty detection as the problem of selecting aerosol parameters whose effective surface reflectance spectrum is not an outlier in some space. In this paper, empirical orthogonal functions, a reconstruction-based novelty detection technique, is used to perform single-pixel aerosol retrieval using the single angular and temporal sample provided by the MODIS sensor. The empirical orthogonal basis functions are trained for different land classes using the MODIS BRDF MCD43 product. Existing land classification products are used in training and aerosol retrieval. The retrieval is compared against the existing operational MODIS 3 KM Dark Target (DT) aerosol product and co-located AERONET data. Based on the comparison, our method allows for a significant increase in retrieval frequency and a moderate decrease in the known biases of MODIS urban aerosol retrievals.
Farzaneh, Saeed; Forootan, Ehsan
2018-03-01
The computerized ionospheric tomography is a method for imaging the Earth's ionosphere using a sounding technique and computing the slant total electron content (STEC) values from data of the global positioning system (GPS). The most common approach for ionospheric tomography is the voxel-based model, in which (1) the ionosphere is divided into voxels, (2) the STEC is then measured along (many) satellite signal paths, and finally (3) an inversion procedure is applied to reconstruct the electron density distribution of the ionosphere. In this study, a computationally efficient approach is introduced, which improves the inversion procedure of step 3. Our proposed method combines the empirical orthogonal function and the spherical Slepian base functions to describe the vertical and horizontal distribution of electron density, respectively. Thus, it can be applied on regional and global case studies. Numerical application is demonstrated using the ground-based GPS data over South America. Our results are validated against ionospheric tomography obtained from the constellation observing system for meteorology, ionosphere, and climate (COSMIC) observations and the global ionosphere map estimated by international centers, as well as by comparison with STEC derived from independent GPS stations. Using the proposed approach, we find that while using 30 GPS measurements in South America, one can achieve comparable accuracy with those from COSMIC data within the reported accuracy (1 × 1011 el/cm3) of the product. Comparisons with real observations of two GPS stations indicate an absolute difference is less than 2 TECU (where 1 total electron content unit, TECU, is 1016 electrons/m2).
Gibson, Justin; Franz, Trenton E.
2018-06-01
The hydrological community often turns to widely available spatial datasets such as the NRCS Soil Survey Geographic database (SSURGO) to characterize the spatial variability of soil properties. When used to spatially characterize and parameterize watershed models, this has served as a reasonable first approximation when lacking localized or incomplete soil data. Within agriculture, soil data has been left relatively coarse when compared to numerous other data sources measured. This is because localized soil sampling is both expensive and time intense, thus a need exists in better connecting spatial datasets with ground observations. Given that hydrogeophysics is data-dense, rapid, non-invasive, and relatively easy to adopt, it is a promising technique to help dovetail localized soil sampling with spatially exhaustive datasets. In this work, we utilize two common near surface geophysical methods, cosmic-ray neutron probe and electromagnetic induction, to identify temporally stable spatial patterns of measured geophysical properties in three 65 ha agricultural fields in western Nebraska. This is achieved by repeat geophysical observations of the same study area across a range of wet to dry field conditions in order to evaluate with an empirical orthogonal function. Shallow cores were then extracted within each identified zone and water retention functions were generated in the laboratory. Using EOF patterns as a covariate, we quantify the predictive skill of estimating soil hydraulic properties in areas without measurement using a bootstrap validation analysis. Results indicate that sampling locations informed via repeat hydrogeophysical surveys, required only five cores to reduce the cross-validation root mean squared error by an average of 64% as compared to soil parameters predicted by a commonly used benchmark, SSURGO and ROSETTA. The reduction to five strategically located samples within the 65 ha fields reduces sampling efforts by up to ∼90% as compared to
An ACE-based Nonlinear Extension to Traditional Empirical Orthogonal Function Analysis
DEFF Research Database (Denmark)
Hilger, Klaus Baggesen; Nielsen, Allan Aasbjerg; Andersen, Ole
2001-01-01
This paper shows the application of the empirical orthogonal unctions/principal component transformation on global sea surface height and temperature data from 1996 and 1997. A nonlinear correlation analysis of the transformed data is proposed and performed by applying the alternating conditional...... expectations algorithm. New canonical variates are found that indicate that the highest correlation between ocean temperature and height is associated with the build-up of the El Niño during the last half of 1997....
Modeling ionospheric foF2 by using empirical orthogonal function analysis
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E. A
2011-08-01
Full Text Available A similar-parameters interpolation method and an empirical orthogonal function analysis are used to construct empirical models for the ionospheric foF2 by using the observational data from three ground-based ionosonde stations in Japan which are Wakkanai (Geographic 45.4° N, 141.7° E, Kokubunji (Geographic 35.7° N, 140.1° E and Yamagawa (Geographic 31.2° N, 130.6° E during the years of 1971–1987. The impact of different drivers towards ionospheric foF2 can be well indicated by choosing appropriate proxies. It is shown that the missing data of original foF2 can be optimal refilled using similar-parameters method. The characteristics of base functions and associated coefficients of EOF model are analyzed. The diurnal variation of base functions can reflect the essential nature of ionospheric foF2 while the coefficients represent the long-term alteration tendency. The 1st order EOF coefficient A1 can reflect the feature of the components with solar cycle variation. A1 also contains an evident semi-annual variation component as well as a relatively weak annual fluctuation component. Both of which are not so obvious as the solar cycle variation. The 2nd order coefficient A2 contains mainly annual variation components. The 3rd order coefficient A3 and 4th order coefficient A4 contain both annual and semi-annual variation components. The seasonal variation, solar rotation oscillation and the small-scale irregularities are also included in the 4th order coefficient A4. The amplitude range and developing tendency of all these coefficients depend on the level of solar activity and geomagnetic activity. The reliability and validity of EOF model are verified by comparison with observational data and with International Reference Ionosphere (IRI. The agreement between observations and EOF model is quite well, indicating that the EOF model can reflect the major changes and the temporal distribution characteristics of the mid-latitude ionosphere of the
A global weighted mean temperature model based on empirical orthogonal function analysis
Li, Qinzheng; Chen, Peng; Sun, Langlang; Ma, Xiaping
2018-03-01
A global empirical orthogonal function (EOF) model of the tropospheric weighted mean temperature called GEOFM_Tm was developed using high-precision Global Geodetic Observing System (GGOS) Atmosphere Tm data during the years 2008-2014. Due to the quick convergence of EOF decomposition, it is possible to use the first four EOF series, which consists base functions Uk and associated coefficients Pk, to represent 99.99% of the overall variance of the original data sets and its spatial-temporal variations. Results show that U1 displays a prominent latitude distribution profile with positive peaks located at low latitude region. U2 manifests an asymmetric pattern that positive values occurred over 30° in the Northern Hemisphere, and negative values were observed at other regions. U3 and U4 displayed significant anomalies in Tibet and North America, respectively. Annual variation is the major component of the first and second associated coefficients P1 and P2, whereas P3 and P4 mainly reflects both annual and semi-annual variation components. Furthermore, the performance of constructed GEOFM_Tm was validated by comparison with GTm_III and GTm_N with different kinds of data including GGOS Atmosphere Tm data in 2015 and radiosonde data from Integrated Global Radiosonde Archive (IGRA) in 2014. Generally speaking, GEOFM_Tm can achieve the same accuracy and reliability as GTm_III and GTm_N models in a global scale, even has improved in the Antarctic and Greenland regions. The MAE and RMS of GEOFM_Tm tend to be 2.49 K and 3.14 K with respect to GGOS Tm data, respectively; and 3.38 K and 4.23 K with respect to IGRA sounding data, respectively. In addition, those three models have higher precision at low latitude than middle and high latitude regions. The magnitude of Tm remains at the range of 220-300 K, presented a high correlation with geographic latitude. In the Northern Hemisphere, there was a significant enhancement at high latitude region reaching 270 K during summer
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W. Korres
2010-05-01
Full Text Available Soil moisture is one of the fundamental variables in hydrology, meteorology and agriculture. Nevertheless, its spatio-temporal patterns in agriculturally used landscapes that are affected by multiple natural (rainfall, soil, topography etc. and agronomic (fertilisation, soil management etc. factors are often not well known. The aim of this study is to determine the dominant factors governing the spatio-temporal patterns of surface soil moisture in a grassland and an arable test site that are located within the Rur catchment in Western Germany. Surface soil moisture (0–6 cm was measured in an approx. 50×50 m grid during 14 and 17 measurement campaigns (May 2007 to November 2008 in both test sites. To analyse the spatio-temporal patterns of surface soil moisture, an Empirical Orthogonal Function (EOF analysis was applied and the results were correlated with parameters derived from topography, soil, vegetation and land management to link the patterns to related factors and processes. For the grassland test site, the analysis resulted in one significant spatial structure (first EOF, which explained 57.5% of the spatial variability connected to soil properties and topography. The statistical weight of the first spatial EOF is stronger on wet days. The highest temporal variability can be found in locations with a high percentage of soil organic carbon (SOC. For the arable test site, the analysis resulted in two significant spatial structures, the first EOF, which explained 38.4% of the spatial variability, and showed a highly significant correlation to soil properties, namely soil texture and soil stone content. The second EOF, which explained 28.3% of the spatial variability, is linked to differences in land management. The soil moisture in the arable test site varied more strongly during dry and wet periods at locations with low porosity. The method applied is capable of identifying the dominant parameters controlling spatio-temporal patterns of
Haluska, J. D.
2017-12-01
Shoreline change along the Eastern Atlantic shore of Virginia has been studied for the individual barrier islands but not as an integrated system. This study combines the Atlantic shoreline locations for eleven barrier islands obtained from LANDSAT 5, 7, and 8 images. Approximately 250 shoreline locations over a 24-year period from Jan 1990 to Dec 2014 were extracted from the digitized shoreline data at 338 transects. The resulting 338 by 250 matrix was analyzed by the empirical orthogonal function (EOF) technique. The first four principal components (PC) explained 86 percent of the sample variance. Since the data was not detrended, the first PC was the overall trend of the data with a discontinuity in 2004-2005. The 2004-2005 interval included storm events and large shoreline changes. PCs 2 to 4 reflect the effects of El Nino events and tropical and non-tropical storms. Eigenvectors 1 to 4 all show the effects of the nine inlets in the island group. Eigenvector (EV) 1 explains 59 percent of the shoreline spatial variance and shows the largest changes at the northern and southern island ends. EVs 2 to 4 reflect the pattern of EV1 but at sequentially smaller percentages of the spatial variance. As a group, the eleven islands are losing ocean side shoreline. The lone exception is Hog Island. Sea level had the strongest correlation with the shoreline loss trend of PC1. The coefficient of determination was 0.41. The NAO and MEI also correlated with PC1 with correlations of determination of 0.05 and 0.12 respectively. These confidence level for the three factors was better than 99 percent. Sea level also correlated with PC3 and PC4. The PCs as a group show that the year intervals 2004-2005 and 2009-2010 had large effects on the shoreline change pattern for the island group. EVs 1 to 4 had the highest range of shoreline change at the island ends indicating the effect the changes of the inlets have on the adjacent islands. The smaller islands as a group had a higher level
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Man Sing Wong
2015-05-01
Full Text Available Water vapor, as one of the most important greenhouse gases, is crucial for both climate and atmospheric studies. Considering the high spatial and temporal variations of water vapor, a timely and accurate retrieval of precipitable water vapor (PWV is urgently needed, but has long been constrained by data availability. Our study derived the vertically integrated precipitable water vapor over eastern China using Multi-functional Transport Satellite (MTSAT data, which is in geostationary orbit with high temporal resolution. The missing pixels caused by cloud contamination were reconstructed using an Empirical Orthogonal Function (EOF decomposition method over both spatial and temporal dimensions. GPS meteorology data were used to validate the retrieval and the reconstructed results. The diurnal variation of PWV over eastern China was analyzed using harmonic analysis, which indicates that the reconstructed PWV data can depict the diurnal cycle of PWV caused by evapotranspiration and local thermal circulation.
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A. Devasthale
2012-02-01
Full Text Available The Advanced Very High Resolution Radiometer (AVHRR instruments onboard the series of National Oceanic and Atmospheric Administration (NOAA satellites offer the longest available meteorological data records from space. These satellites have drifted in orbit resulting in shifts in the local time sampling during the life span of the sensors onboard. Depending upon the amplitude of the diurnal cycle of the geophysical parameters derived, orbital drift may cause spurious trends in their time series. We investigate tropical deep convective clouds, which show pronounced diurnal cycle amplitude, to estimate an upper bound of the impact of orbital drift on their time series. We carry out a rotated empirical orthogonal function analysis (REOF and show that the REOFs are useful in delineating orbital drift signal and, more importantly, in subtracting this signal in the time series of convective cloud amount. These results will help facilitate the derivation of homogenized data series of cloud amount from NOAA satellite sensors and ultimately analyzing trends from them. However, we suggest detailed comparison of various methods and rigorous testing thereof applying final orbital drift corrections.
Feng, Fei; Li, Xianglan; Yao, Yunjun; Liang, Shunlin; Chen, Jiquan; Zhao, Xiang; Jia, Kun; Pintér, Krisztina; McCaughey, J Harry
2016-01-01
Accurate estimation of latent heat flux (LE) based on remote sensing data is critical in characterizing terrestrial ecosystems and modeling land surface processes. Many LE products were released during the past few decades, but their quality might not meet the requirements in terms of data consistency and estimation accuracy. Merging multiple algorithms could be an effective way to improve the quality of existing LE products. In this paper, we present a data integration method based on modified empirical orthogonal function (EOF) analysis to integrate the Moderate Resolution Imaging Spectroradiometer (MODIS) LE product (MOD16) and the Priestley-Taylor LE algorithm of Jet Propulsion Laboratory (PT-JPL) estimate. Twenty-two eddy covariance (EC) sites with LE observation were chosen to evaluate our algorithm, showing that the proposed EOF fusion method was capable of integrating the two satellite data sets with improved consistency and reduced uncertainties. Further efforts were needed to evaluate and improve the proposed algorithm at larger spatial scales and time periods, and over different land cover types.
Li, Lingqi; Gottschalk, Lars; Krasovskaia, Irina; Xiong, Lihua
2018-01-01
Reconstruction of missing runoff data is of important significance to solve contradictions between the common situation of gaps and the fundamental necessity of complete time series for reliable hydrological research. The conventional empirical orthogonal functions (EOF) approach has been documented to be useful for interpolating hydrological series based upon spatiotemporal decomposition of runoff variation patterns, without additional measurements (e.g., precipitation, land cover). This study develops a new EOF-based approach (abbreviated as CEOF) that conditions EOF expansion on the oscillations at outlet (or any other reference station) of a target basin and creates a set of residual series by removing the dependence on this reference series, in order to redefine the amplitude functions (components). This development allows a transparent hydrological interpretation of the dimensionless components and thereby strengthens their capacities to explain various runoff regimes in a basin. The two approaches are demonstrated on an application of discharge observations from the Ganjiang basin, China. Two alternatives for determining amplitude functions based on centred and standardised series, respectively, are tested. The convergence in the reconstruction of observations at different sites as a function of the number of components and its relation to the characteristics of the site are analysed. Results indicate that the CEOF approach offers an efficient way to restore runoff records with only one to four components; it shows more superiority in nested large basins than at headwater sites and often performs better than the EOF approach when using standardised series, especially in improving infilling accuracy for low flows. Comparisons against other interpolation methods (i.e., nearest neighbour, linear regression, inverse distance weighting) further confirm the advantage of the EOF-based approaches in avoiding spatial and temporal inconsistencies in estimated series.
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S. Sparnocchia
Full Text Available Multivariate vertical Empirical Orthogonal Functions (EOF are calculated for the entire Mediterranean Sea both from observations and model simulations, in order to find the optimal number of vertical modes to represent the upper thermocline vertical structure. For the first time, we show that the large-scale Mediterranean thermohaline vertical structure can be represented by a limited number of vertical multivariate EOFs, and that the "optimal set" can be selected on the basis of general principles. In particular, the EOFs are calculated for the combined temperature and salinity statistics, dividing the Mediterranean Sea into 9 regions and grouping the data seasonally. The criterion used to establish whether a reduced set of EOFs is optimal is based on the analysis of the root mean square residual error between the original data and the profiles reconstructed by the reduced set of EOFs. It was found that the number of EOFs needed to capture the variability contained in the original data changes with geographical region and seasons. In particular, winter data require a smaller number of modes (4–8, depending on the region than the other seasons (8–9 in summer. Moreover, western Mediterranean regions require more modes than the eastern Mediterranean ones, but this result may depend on the data scarcity in the latter regions. The EOFs computed from the in situ data set are compared to those calculated using data obtained from a model simulation. The main results of this exercise are that the two groups of modes are not strictly comparable but their ability to reproduce observations is the same. Thus, they may be thought of as equivalent sets of basis functions, upon which to project the thermohaline variability of the basin.
Key words. Oceanography: general (water masses – Oceanography: physical (hydrography; instruments and techniques
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S. Sparnocchia
2003-01-01
Full Text Available Multivariate vertical Empirical Orthogonal Functions (EOF are calculated for the entire Mediterranean Sea both from observations and model simulations, in order to find the optimal number of vertical modes to represent the upper thermocline vertical structure. For the first time, we show that the large-scale Mediterranean thermohaline vertical structure can be represented by a limited number of vertical multivariate EOFs, and that the "optimal set" can be selected on the basis of general principles. In particular, the EOFs are calculated for the combined temperature and salinity statistics, dividing the Mediterranean Sea into 9 regions and grouping the data seasonally. The criterion used to establish whether a reduced set of EOFs is optimal is based on the analysis of the root mean square residual error between the original data and the profiles reconstructed by the reduced set of EOFs. It was found that the number of EOFs needed to capture the variability contained in the original data changes with geographical region and seasons. In particular, winter data require a smaller number of modes (4–8, depending on the region than the other seasons (8–9 in summer. Moreover, western Mediterranean regions require more modes than the eastern Mediterranean ones, but this result may depend on the data scarcity in the latter regions. The EOFs computed from the in situ data set are compared to those calculated using data obtained from a model simulation. The main results of this exercise are that the two groups of modes are not strictly comparable but their ability to reproduce observations is the same. Thus, they may be thought of as equivalent sets of basis functions, upon which to project the thermohaline variability of the basin. Key words. Oceanography: general (water masses – Oceanography: physical (hydrography; instruments and techniques
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Marco Correa-Ramirez
2018-03-01
Full Text Available An approach that improves the spectral-based PHYSAT method for identifying phytoplankton functional types (PFT in satellite ocean-color imagery is developed and applied to one study case. This new approach, called PHYSTWO, relies on the assumption that the dominant effect of chlorophyll-a (Chl-a in the normalized water-leaving radiance (nLw spectrum can be effectively isolated from the signal of accessory pigment biomarkers of different PFT by using Empirical Orthogonal Function (EOF decomposition. PHYSTWO operates in the dimensionless plane composed by the first two EOF modes generated through the decomposition of a space–nLw matrix at seven wavelengths (412, 443, 469, 488, 531, 547, and 555 nm. PFT determination is performed using orthogonal models derived from the acceptable ranges of anomalies proposed by PHYSAT but adjusted with the available regional and global data. In applying PHYSTWO to study phytoplankton community structures in the coastal upwelling system off central Chile, we find that this method increases the accuracy of PFT identification, extends the application of this tool to waters with high Chl-a concentration, and significantly decreases (~60% the undetermined retrievals when compared with PHYSAT. The improved accuracy of PHYSTWO and its applicability for the identification of new PFT are discussed.
Orthogonal Polynomials and Special Functions
Assche, Walter
2003-01-01
The set of lectures from the Summer School held in Leuven in 2002 provide an up-to-date account of recent developments in orthogonal polynomials and special functions, in particular for algorithms for computer algebra packages, 3nj-symbols in representation theory of Lie groups, enumeration, multivariable special functions and Dunkl operators, asymptotics via the Riemann-Hilbert method, exponential asymptotics and the Stokes phenomenon. The volume aims at graduate students and post-docs working in the field of orthogonal polynomials and special functions, and in related fields interacting with orthogonal polynomials, such as combinatorics, computer algebra, asymptotics, representation theory, harmonic analysis, differential equations, physics. The lectures are self-contained requiring only a basic knowledge of analysis and algebra, and each includes many exercises.
El Serafy, Ghada; Gaytan Aguilar, Sandra; Ziemba, Alexander
2016-04-01
There is an increasing use of process-based models in the investigation of ecological systems and scenario predictions. The accuracy and quality of these models are improved when run with high spatial and temporal resolution data sets. However, ecological data can often be difficult to collect which manifests itself through irregularities in the spatial and temporal domain of these data sets. Through the use of Data INterpolating Empirical Orthogonal Functions(DINEOF) methodology, earth observation products can be improved to have full spatial coverage within the desired domain as well as increased temporal resolution to daily and weekly time step, those frequently required by process-based models[1]. The DINEOF methodology results in a degree of error being affixed to the refined data product. In order to determine the degree of error introduced through this process, the suspended particulate matter and chlorophyll-a data from MERIS is used with DINEOF to produce high resolution products for the Wadden Sea. These new data sets are then compared with in-situ and other data sources to determine the error. Also, artificial cloud cover scenarios are conducted in order to substantiate the findings from MERIS data experiments. Secondly, the accuracy of DINEOF is explored to evaluate the variance of the methodology. The degree of accuracy is combined with the overall error produced by the methodology and reported in an assessment of the quality of DINEOF when applied to resolution refinement of chlorophyll-a and suspended particulate matter in the Wadden Sea. References [1] Sirjacobs, D.; Alvera-Azcárate, A.; Barth, A.; Lacroix, G.; Park, Y.; Nechad, B.; Ruddick, K.G.; Beckers, J.-M. (2011). Cloud filling of ocean colour and sea surface temperature remote sensing products over the Southern North Sea by the Data Interpolating Empirical Orthogonal Functions methodology. J. Sea Res. 65(1): 114-130. Dx.doi.org/10.1016/j.seares.2010.08.002
Symmetric functions and orthogonal polynomials
Macdonald, I G
1997-01-01
One of the most classical areas of algebra, the theory of symmetric functions and orthogonal polynomials has long been known to be connected to combinatorics, representation theory, and other branches of mathematics. Written by perhaps the most famous author on the topic, this volume explains some of the current developments regarding these connections. It is based on lectures presented by the author at Rutgers University. Specifically, he gives recent results on orthogonal polynomials associated with affine Hecke algebras, surveying the proofs of certain famous combinatorial conjectures.
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R. Zhuravlev
2011-10-01
Full Text Available In this work we propose an approach to solving a source estimation problem based on representation of carbon dioxide surface emissions as a linear combination of a finite number of pre-computed empirical orthogonal functions (EOFs. We used National Institute for Environmental Studies (NIES transport model for computing response functions and Kalman filter for estimating carbon dioxide emissions. Our approach produces results similar to these of other models participating in the TransCom3 experiment.
Using the EOFs we can estimate surface fluxes at higher spatial resolution, while keeping the dimensionality of the problem comparable with that in the regions approach. This also allows us to avoid potentially artificial sharp gradients in the fluxes in between pre-defined regions. EOF results generally match observations more closely given the same error structure as the traditional method.
Additionally, the proposed approach does not require additional effort of defining independent self-contained emission regions.
Huang, C. L.; Hsu, N. S.; Yeh, W. W. G.; Hsieh, I. H.
2017-12-01
This study develops an innovative calibration method for regional groundwater modeling by using multi-class empirical orthogonal functions (EOFs). The developed method is an iterative approach. Prior to carrying out the iterative procedures, the groundwater storage hydrographs associated with the observation wells are calculated. The combined multi-class EOF amplitudes and EOF expansion coefficients of the storage hydrographs are then used to compute the initial gauss of the temporal and spatial pattern of multiple recharges. The initial guess of the hydrogeological parameters are also assigned according to in-situ pumping experiment. The recharges include net rainfall recharge and boundary recharge, and the hydrogeological parameters are riverbed leakage conductivity, horizontal hydraulic conductivity, vertical hydraulic conductivity, storage coefficient, and specific yield. The first step of the iterative algorithm is to conduct the numerical model (i.e. MODFLOW) by the initial guess / adjusted values of the recharges and parameters. Second, in order to determine the best EOF combination of the error storage hydrographs for determining the correction vectors, the objective function is devised as minimizing the root mean square error (RMSE) of the simulated storage hydrographs. The error storage hydrograph are the differences between the storage hydrographs computed from observed and simulated groundwater level fluctuations. Third, adjust the values of recharges and parameters and repeat the iterative procedures until the stopping criterion is reached. The established methodology was applied to the groundwater system of Ming-Chu Basin, Taiwan. The study period is from January 1st to December 2ed in 2012. Results showed that the optimal EOF combination for the multiple recharges and hydrogeological parameters can decrease the RMSE of the simulated storage hydrographs dramatically within three calibration iterations. It represents that the iterative approach that
Predicting coastal morphological changes with empirical orthogonal functionmethod
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Fernando Alvarez
2016-01-01
Full Text Available In order to improve the accuracy of prediction when using the empirical orthogonal function (EOF method, this paper describes a novel approach for two-dimensional (2D EOF analysis based on extrapolating both the spatial and temporal EOF components for long-term prediction of coastal morphological changes. The approach was investigated with data obtained from a process-based numerical model, COAST2D, which was applied to an idealized study site with a group of shore-parallel breakwaters. The progressive behavior of the spatial and temporal EOF components, related to bathymetric changes over a training period, was demonstrated, and EOF components were extrapolated with combined linear and exponential functions for long-term prediction. The extrapolated EOF components were then used to reconstruct bathymetric changes. The comparison of the reconstructed bathymetric changes with the modeled results from the COAST2D model illustrates that the presented approach can be effective for long-term prediction of coastal morphological changes, and extrapolating both the spatial and temporal EOF components yields better results than extrapolating only the temporal EOF component.
Hypergeometric series recurrence relations and some new orthogonal functions
International Nuclear Information System (INIS)
Wilson, J.A.
1978-01-01
A set of hypergeometric orthogonal polynomials, a set of biorthogonal rational functions generalizing them, and some new three-term relations for hypergeometric series containing properties of these functions are exhibited. The orthogonal polynomials depend on four free parameters, and their orthogonality relations include as special or limiting cases the orthogonalities for the classical polynomials, the Hahn and dual Hahn polynomials, Pollaczek's polynomials orthogonal on an infinite interval, and the 6-j symbols of angular momentum in quantum mechanics. Their properties include a second-order difference equation and a Rodrigues-type formula involving a divided difference operator
Transfer Function Identification Using Orthogonal Fourier Transform Modeling Functions
Morelli, Eugene A.
2013-01-01
A method for transfer function identification, including both model structure determination and parameter estimation, was developed and demonstrated. The approach uses orthogonal modeling functions generated from frequency domain data obtained by Fourier transformation of time series data. The method was applied to simulation data to identify continuous-time transfer function models and unsteady aerodynamic models. Model fit error, estimated model parameters, and the associated uncertainties were used to show the effectiveness of the method for identifying accurate transfer function models from noisy data.
Orthogonal bases of radial functions for charge density refinements
International Nuclear Information System (INIS)
Restori, R.
1990-01-01
Charge density determination from X-ray measurements necessitates the evaluation of the Fourier-Bessel transforms of the radial functions used to expand the charge density. Analytical expressions are given here for four sets of orthogonal functions which can substitute for the 'traditional exponential functions' set in least-squares refinements. (orig.)
Consequences of wave function orthogonality for medium energy nuclear reactions
International Nuclear Information System (INIS)
Noble, J.V.
1978-01-01
In the usual models of high-energy bound-state to continuum transitions no account is taken of the orthogonality of the bound and continuum wave functions. This orthogonality induces considerable cancellations in the overlap integrals expressing the transition amplitudes for reactions such as (e,e'p), (γ,p), and (π,N), which are simply not included in the distorted-wave Born-approximation calculations which to date remain the only computationally feasible heirarchy of approximations. The object of this paper is to present a new formulation of the bound-state to continuum transition problem, based upon flux conservation, in which the orthogonality of wave functions is taken into account ab initio. The new formulation, while exact if exact wave functions are used, offers the possibility of using approximate wave functions for the continuum states without doing violence to the cancellations induced by orthogonality. The method is applied to single-particle states obeying the Schroedinger and Dirac equations, as well as to a coupled-channel model in which absorptive processes can be described in a fully consistent manner. Several types of absorption vertex are considered, and in the (π,N) case the equivalence of pseudoscalar and pseudovector πNN coupling is seen to follow directly from wave function orthogonality
Empirical microeconomics action functionals
Baaquie, Belal E.; Du, Xin; Tanputraman, Winson
2015-06-01
A statistical generalization of microeconomics has been made in Baaquie (2013), where the market price of every traded commodity, at each instant of time, is considered to be an independent random variable. The dynamics of commodity market prices is modeled by an action functional-and the focus of this paper is to empirically determine the action functionals for different commodities. The correlation functions of the model are defined using a Feynman path integral. The model is calibrated using the unequal time correlation of the market commodity prices as well as their cubic and quartic moments using a perturbation expansion. The consistency of the perturbation expansion is verified by a numerical evaluation of the path integral. Nine commodities drawn from the energy, metal and grain sectors are studied and their market behavior is described by the model to an accuracy of over 90% using only six parameters. The paper empirically establishes the existence of the action functional for commodity prices that was postulated to exist in Baaquie (2013).
orthogonal and scaling transformations of quadratic functions
African Journals Online (AJOL)
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functions of sub-problems of various nonlinear programming problems that employ methods such as sequential quadratic programming and trust-region methods (Sorensen, 1982; Eldersveld,. 1991; Nocedal and Wright, 1999). Various problems in Algebra, Functional Analysis,. Analytic Geometry and Computational Mathe-.
Orthogonal functions, discrete variable representation, and generalized gauss quadratures
DEFF Research Database (Denmark)
Schneider, B. I.; Nygaard, Nicolai
2002-01-01
in the original representation. This has been exploited in bound-state, scattering, and time-dependent problems using the so-called, discrete variable representation (DVR). At the core of this approach is the mathematical three-term recursion relationship satisfied by the classical orthogonal functions...... functions, this is not the case. However, they may be computed in a stable numerical fashion, via the recursion. In essence, this is an application of the well-known Lanczos recursion approach. Once the recursion coefficients are known, it is possible to compute the points and weights of quadratures on...
Properties of the Magnitude Terms of Orthogonal Scaling Functions.
Tay, Peter C; Havlicek, Joseph P; Acton, Scott T; Hossack, John A
2010-09-01
The spectrum of the convolution of two continuous functions can be determined as the continuous Fourier transform of the cross-correlation function. The same can be said about the spectrum of the convolution of two infinite discrete sequences, which can be determined as the discrete time Fourier transform of the cross-correlation function of the two sequences. In current digital signal processing, the spectrum of the contiuous Fourier transform and the discrete time Fourier transform are approximately determined by numerical integration or by densely taking the discrete Fourier transform. It has been shown that all three transforms share many analogous properties. In this paper we will show another useful property of determining the spectrum terms of the convolution of two finite length sequences by determining the discrete Fourier transform of the modified cross-correlation function. In addition, two properties of the magnitude terms of orthogonal wavelet scaling functions are developed. These properties are used as constraints for an exhaustive search to determine an robust lower bound on conjoint localization of orthogonal scaling functions.
Orthogonal functions, discrete variable representation, and generalized gauss quadratures
DEFF Research Database (Denmark)
Schneider, B. I.; Nygaard, Nicolai
2002-01-01
in the original representation. This has been exploited in bound-state, scattering, and time-dependent problems using the so-called, discrete variable representation (DVR). At the core of this approach is the mathematical three-term recursion relationship satisfied by the classical orthogonal functions......, the distinction between spectral and grid approaches becomes blurred. In fact, the two approaches can be related by a similarity transformation. By the exploitation of this idea, calculations can be considerably simplified by removing the need to compute difficult matrix elements of the Hamiltonian...... functions, this is not the case. However, they may be computed in a stable numerical fashion, via the recursion. In essence, this is an application of the well-known Lanczos recursion approach. Once the recursion coefficients are known, it is possible to compute the points and weights of quadratures on...
Discriminants and functional equations for polynomials orthogonal on the unit circle
International Nuclear Information System (INIS)
Ismail, M.E.H.; Witte, N.S.
2000-01-01
We derive raising and lowering operators for orthogonal polynomials on the unit circle and find second order differential and q-difference equations for these polynomials. A general functional equation is found which allows one to relate the zeros of the orthogonal polynomials to the stationary values of an explicit quasi-energy and implies recurrences on the orthogonal polynomial coefficients. We also evaluate the discriminants and quantized discriminants of polynomials orthogonal on the unit circle
Empirical Specification of Utility Functions.
Mellenbergh, Gideon J.
Decision theory can be applied to four types of decision situations in education and psychology: (1) selection; (2) placement; (3) classification; and (4) mastery. For the application of the theory, a utility function must be specified. Usually the utility function is chosen on a priori grounds. In this paper methods for the empirical assessment…
International Nuclear Information System (INIS)
Li Shun; Zhang Sijiong
2014-01-01
A numerical model is presented to simulate the influence function of deformable mirror actuators. The numerical model is formed by Bessel Fourier orthogonal functions, which are constituted of Bessel orthogonal functions and a Fourier basis. A detailed comparison is presented between the new Bessel Fourier model, the Zernike model, the Gaussian influence function and the modified Gaussian influence function. Numerical experiments indicate that the new numerical model is easy to use and more accurate compared with other numerical models. The new numerical model can be used for describing deformable mirror performances and numerical simulations of adaptive optics systems. (research papers)
Orthogonal rational functions on the unit circle: from the scalar to the matrix case.
Bultheel, A.; Gonzalez-Vera, P.; Hendriksen, E.; Njastad, O.
2006-01-01
Special functions and orthogonal polynomials in particular have been around for centuries. Can you imagine mathematics without trigonometric functions, the exponential function or polynomials? In the twentieth century the emphasis was on special functions satisfying linear differential equations,
A Bivariate Extension to Traditional Empirical Orthogonal Function Analysis
DEFF Research Database (Denmark)
Nielsen, Allan Aasbjerg; Hilger, Klaus Baggesen; Andersen, Ole Baltazar
2002-01-01
This paper describes the application of canonical correlations analysis to the joint analysis of global monthly mean values of 1996-1997 sea surface temperature (SST) and height (SSH) data. The SST data are considered as one set and the SSH data as another set of multivariate observations, both w...... as for example an increase in the SST will lead to an increase in the SSH. The analysis clearly shows the build-up of one of the largest El Niño events on record. Also the analysis indicates a phase lag of approximately one month between the SST and SSH fields....
A Temporal Extension to Traditional Empirical Orthogonal Function Analysis
DEFF Research Database (Denmark)
Nielsen, Allan Aasbjerg; Hilger, Klaus Baggesen; Andersen, Ole Baltazar
2002-01-01
(EOF) analysis, which provides a non-temporal analysis of one variable over time. The temporal extension proves its strength in separating the signals at different periods in an analysis of relevant oceanographic properties related to one of the largest El Niño events ever recorded....
An Empirical Mass Function Distribution
Murray, S. G.; Robotham, A. S. G.; Power, C.
2018-03-01
The halo mass function, encoding the comoving number density of dark matter halos of a given mass, plays a key role in understanding the formation and evolution of galaxies. As such, it is a key goal of current and future deep optical surveys to constrain the mass function down to mass scales that typically host {L}\\star galaxies. Motivated by the proven accuracy of Press–Schechter-type mass functions, we introduce a related but purely empirical form consistent with standard formulae to better than 4% in the medium-mass regime, {10}10{--}{10}13 {h}-1 {M}ȯ . In particular, our form consists of four parameters, each of which has a simple interpretation, and can be directly related to parameters of the galaxy distribution, such as {L}\\star . Using this form within a hierarchical Bayesian likelihood model, we show how individual mass-measurement errors can be successfully included in a typical analysis, while accounting for Eddington bias. We apply our form to a question of survey design in the context of a semi-realistic data model, illustrating how it can be used to obtain optimal balance between survey depth and angular coverage for constraints on mass function parameters. Open-source Python and R codes to apply our new form are provided at http://mrpy.readthedocs.org and https://cran.r-project.org/web/packages/tggd/index.html respectively.
Directory of Open Access Journals (Sweden)
Monika GARG
2012-08-01
Full Text Available In this paper, an integrated approach is proposed for non-recursive formulation of connection coefficients of different orthogonal functions in terms of a generic orthogonal function. The application of these coefficients arises when the product of two orthogonal basis functions are to be expressed in terms of single basis functions. Two significant advantages are achieved; one, the non-recursive formulations avoid memory and stack overflows in computer implementations; two, the integrated approach provides for digital hardware once-designed can be used for different functions. Computational savings achieved with the proposed non-recursive formulation vis-à-vis recursive formulation, reported in the literature so far, have been demonstrated using MATLAB PROFILER.
Orthogonal and Scaling Transformations of Quadratic Functions with ...
African Journals Online (AJOL)
In this paper we present a non-singular transformation that can reduce a given quadratic function defined on Rn to another simpler quadratic function and study the impact of the transformation in relation to the problem of minimization of the function. In particular, we construct a non-singular transformation that can reduce a ...
Empirical distribution function under heteroscedasticity
Czech Academy of Sciences Publication Activity Database
Víšek, Jan Ámos
2011-01-01
Roč. 45, č. 5 (2011), s. 497-508 ISSN 0233-1888 Grant - others:GA UK(CZ) GA402/09/0557 Institutional research plan: CEZ:AV0Z10750506 Keywords : Robustness * Convergence * Empirical distribution * Heteroscedasticity Subject RIV: BB - Applied Statistics , Operational Research Impact factor: 0.724, year: 2011 http://library.utia.cas.cz/separaty/2011/SI/visek-0365534.pdf
Directory of Open Access Journals (Sweden)
Tim eAppelhans
2016-02-01
Full Text Available East Africa is characterized by a rather dry annual precipitation climatology with two distinct rainy seasons. In order to investigate sea surface temperature driven precipitation anomalies for the region we use the algorithm of empirical orthogonal teleconnection analysis as a data mining tool. We investigate the entire East African domain as well as 5 smaller sub-regions mainly located in areas of mountainous terrain. In searching for influential sea surface temperature patterns we do not focus any particular season or oceanic region. Furthermore, we investigate different time lags from zero to twelve months. The strongest influence is identified for the immediate (i.e. non-lagged influences of the Indian Ocean in close vicinity to the East African coast. None of the most important modes are located in the tropical Pacific Ocean, though the region is sometimes coupled with the Indian Ocean basin. Furthermore, we identify a region in the southern Indian Ocean around the Kerguelen Plateau which has not yet been reported in the literature with regard to precipitation modulation in East Africa. Finally, it is observed that not all regions in East Africa are equally influenced by the identified patterns.
Orthogonal functionalization of nanoporous substrates: control of 3D surface functionality.
Lazzara, Thomas D; Kliesch, Torben-Tobias; Janshoff, Andreas; Steinem, Claudia
2011-04-01
Anodic aluminum oxide (AAO) membranes with aligned, cylindrical, nonintersecting pores were selectively functionalized in order to create dual-functionality substrates with different pore-rim and pore-interior surface functionalities, using silane chemistry. We used a two-step process involving an evaporated thin gold film to protect the underlying surface functionality of the pore rims. Subsequent treatment with oxygen plasma of the modified AAO membrane removed the unprotected organic functional groups, i.e., the pore-interior surface. After gold removal, the substrate became optically transparent, and displayed two distinct surface functionalities, one at the pore-rim surface and another at the pore-interior surface. We achieved a selective hydrophobic functionalization with dodecyl-trichlorosilane of either the pore rims or the pore interiors. The deposition of planar lipid membranes on the functionalized areas by addition of small unilamellar vesicles occurred in a predetermined fashion. Small unilamellar vesicles only ruptured upon contact with the hydrophobic substrate regions forming solid supported hybrid bilayers. In addition, pore-rim functionalization with dodecyl-trichlorosilane allowed the formation of pore-spanning hybrid lipid membranes as a result of giant unilamellar vesicle rupture. Confocal laser scanning microscopy was employed to identify the selective spatial localization of the adsorbed fluorescently labeled lipids. The corresponding increase in the AAO refractive index due to lipid adsorption on the hydrophobic regions was monitored by optical waveguide spectroscopy. This simple orthogonal functionalization route is a promising method to control the three-dimensional surface functionality of nanoporous films. © 2011 American Chemical Society
Differential forms orthogonal to holomorphic functions or forms, and their properties
Aizenberg, L A
1983-01-01
The authors consider the problem of characterizing the exterior differential forms which are orthogonal to holomorphic functions (or forms) in a domain D\\subset {\\mathbf C}^n with respect to integration over the boundary, and some related questions. They give a detailed account of the derivation of the Bochner-Martinelli-Koppelman integral representation of exterior differential forms, which was obtained in 1967 and has already found many important applications. They study the properties of \\overline \\partial-closed forms of type (p, n - 1), 0\\leq p\\leq n - 1, which turn out to be the duals (with respect to the orthogonality mentioned above) to holomorphic functions (or forms) in several complex variables, and resemble holomorphic functions of one complex variable in their properties.
Generalizations of orthogonal polynomials
Bultheel, A.; Cuyt, A.; van Assche, W.; van Barel, M.; Verdonk, B.
2005-07-01
We give a survey of recent generalizations of orthogonal polynomials. That includes multidimensional (matrix and vector orthogonal polynomials) and multivariate versions, multipole (orthogonal rational functions) variants, and extensions of the orthogonality conditions (multiple orthogonality). Most of these generalizations are inspired by the applications in which they are applied. We also give a glimpse of these applications, which are usually generalizations of applications where classical orthogonal polynomials also play a fundamental role: moment problems, numerical quadrature, rational approximation, linear algebra, recurrence relations, and random matrices.
No need for external orthogonality in subsystem density-functional theory.
Unsleber, Jan P; Neugebauer, Johannes; Jacob, Christoph R
2016-08-03
Recent reports on the necessity of using externally orthogonal orbitals in subsystem density-functional theory (SDFT) [Annu. Rep. Comput. Chem., 8, 2012, 53; J. Phys. Chem. A, 118, 2014, 9182] are re-investigated. We show that in the basis-set limit, supermolecular Kohn-Sham-DFT (KS-DFT) densities can exactly be represented as a sum of subsystem densities, even if the subsystem orbitals are not externally orthogonal. This is illustrated using both an analytical example and in basis-set free numerical calculations for an atomic test case. We further show that even with finite basis sets, SDFT calculations using accurate reconstructed potentials can closely approach the supermolecular KS-DFT density, and that the deviations between SDFT and KS-DFT decrease as the basis-set limit is approached. Our results demonstrate that formally, there is no need to enforce external orthogonality in SDFT, even though this might be a useful strategy when developing projection-based DFT embedding schemes.
A Data Forward Stepwise Fitting Algorithm Based on Orthogonal Function System
Directory of Open Access Journals (Sweden)
Li Han-Ju
2017-01-01
Full Text Available Data fitting is the main method of functional data analysis, and it is widely used in the fields of economy, social science, engineering technology and so on. Least square method is the main method of data fitting, but the least square method is not convergent, no memory property, big fitting error and it is easy to over fitting. Based on the orthogonal trigonometric function system, this paper presents a data forward stepwise fitting algorithm. This algorithm takes forward stepwise fitting strategy, each time using the nearest base function to fit the residual error generated by the previous base function fitting, which makes the residual mean square error minimum. In this paper, we theoretically prove the convergence, the memory property and the fitting error diminishing character for the algorithm. Experimental results show that the proposed algorithm is effective, and the fitting performance is better than that of the least square method and the forward stepwise fitting algorithm based on the non-orthogonal function system.
Orthogonality, Lommel integrals and cross product zeros of linear combinations of Bessel functions.
Ziener, Christian H; Kurz, Felix T; Buschle, Lukas R; Kampf, Thomas
2015-01-01
The cylindrical Bessel differential equation and the spherical Bessel differential equation in the interval [Formula: see text] with Neumann boundary conditions are considered. The eigenfunctions are linear combinations of the Bessel function [Formula: see text] or linear combinations of the spherical Bessel functions [Formula: see text]. The orthogonality relations with analytical expressions for the normalization constant are given. Explicit expressions for the Lommel integrals in terms of Lommel functions are derived. The cross product zeros [Formula: see text] and [Formula: see text] are considered in the complex plane for real as well as complex values of the index [Formula: see text] and approximations for the exceptional zero [Formula: see text] are obtained. A numerical scheme based on the discretization of the two-dimensional and three-dimensional Laplace operator with Neumann boundary conditions is presented. Explicit representations of the radial part of the Laplace operator in form of a tridiagonal matrix allow the simple computation of the cross product zeros.
Revisiting the orthogonality of Bessel functions of the first kind on an infinite interval
International Nuclear Information System (INIS)
Leon, J Ponce de
2015-01-01
The rigorous proof of the orthogonality integral ∫ 0 ∞ ρ J ν (kρ)J ν (k ′ ρ) dρ=((δ(k−k ′ ))/k), for ν>=−1, is laborious and requires the use of mathematical techniques that, probably, are unfamiliar to most physics students, even at the graduate level. In physics, we are used to the argument that it may be proved by the use of Hankel transforms. However, the logic of the matter is the opposite, i.e., the existence of the inverse Hankel transform is a consequence of the orthogonality integral. The goal of this work is to prove this integral without circular reasoning. In this paper, using elementary properties of Bessel functions, we give a simple analytical derivation of this integral for the case where ν is an integer, zero, or half-integer not less than −1/2. Then, using the asymptotic behaviour of J ν (x), we extend the result to any ν>=−1. This work is of a pedagogical nature. Therefore, to add educational value to the discussion, we do not skip the details of the calculations. (paper)
Control of modular multilevel converters based on time-scale analysis and orthogonal functions
DEFF Research Database (Denmark)
Zarri, L.; Tani, A.; Mengoni, M.
2014-01-01
current is still a complex task and cannot be fully tackled with traditional linear control techniques. In this paper a multiple time-scale analysis is proposed to determine an approximated model of the MMC that can be used to solve the control problem of the capacitor voltages. In addition, it is shown...... that the reference signal of the circulating current can be built by combining orthogonal functions of the measured voltages and currents. Numerical simulations are used to test the feasibility of the developed approach.......Modular multilevel converter (MMC) is a promising multilevel topology for high-voltage applications that has been developed in recent years. The control of MMCs has been analyzed in detail in many papers, showing that the converter capacitors can be kept charged and balanced by controlling...
Directory of Open Access Journals (Sweden)
Unai Ganzedo
2013-10-01
Full Text Available The information provided by the International Commission for the Conservation of Atlantic Tunas (ICCAT on captures of skipjack tuna (Katsuwonus pelamis in the central-east Atlantic has a number of limitations, such as gaps in the statistics for certain fleets and the level of spatiotemporal detail at which catches are reported. As a result, the quality of these data and their effectiveness for providing management advice is limited. In order to reconstruct missing spatiotemporal data of catches, the present study uses Data INterpolating Empirical Orthogonal Functions (DINEOF, a technique for missing data reconstruction, applied here for the first time to fisheries data. DINEOF is based on an Empirical Orthogonal Functions decomposition performed with a Lanczos method. DINEOF was tested with different amounts of missing data, intentionally removing values from 3.4% to 95.2% of data loss, and then compared with the same data set with no missing data. These validation analyses show that DINEOF is a reliable methodological approach of data reconstruction for the purposes of fishery management advice, even when the amount of missing data is very high.
Orthogonal use of a human tRNA synthetase active site to achieve multi-functionality
Zhou, Quansheng; Kapoor, Mili; Guo, Min; Belani, Rajesh; Xu, Xiaoling; Kiosses, William B.; Hanan, Melanie; Park, Chulho; Armour, Eva; Do, Minh-Ha; Nangle, Leslie A.; Schimmel, Paul; Yang, Xiang-Lei
2011-01-01
Protein multi-functionality is an emerging explanation for the complexity of higher organisms. In this regard, while aminoacyl tRNA synthetases catalyze amino acid activation for protein synthesis, some also act in pathways for inflammation, angiogenesis, and apoptosis. How multiple functions evolved and their relationship to the active site is not clear. Here structural modeling analysis, mutagenesis, and cell-based functional studies show that the potent angiostatic, natural fragment of human TrpRS associates via Trp side chains that protrude from the cognate cellular receptor VE-cadherin. Modeling indicates that (I prefer the way it was because the conclusion was reached not only by modeling, but more so by experimental studies.)VE-cadherin Trp side chains fit into the Trp-specific active site of the synthetase. Thus, specific side chains of the receptor mimic (?) amino acid substrates and expand the functionality of the active site of the synthetase. We propose that orthogonal use of the same active site may be a general way to develop multi-functionality of human tRNA synthetases and other proteins. PMID:20010843
Dong, Shuo; Kettenbach, Joachim; Hinterleitner, Isabella; Bergmann, Helmar; Birkfellner, Wolfgang
2008-01-01
Current merit functions for 2D/3D registration usually rely on comparing pixels or small regions of images using some sort of statistical measure. Problems connected to this paradigm the sometimes problematic behaviour of the method if noise or artefacts (for instance a guide wire) are present on the projective image. We present a merit function for 2D/3D registration which utilizes the decomposition of the X-ray and the DRR under comparison into orthogonal Zernike moments; the quality of the match is assessed by an iterative comparison of expansion coefficients. Results in a imaging study on a physical phantom show that--compared to standard cross--correlation the Zernike moment based merit function shows better robustness if histogram content in images under comparison is different, and that time expenses are comparable if the merit function is constructed out of a few significant moments only.
Empirical validation of directed functional connectivity.
Mill, Ravi D; Bagic, Anto; Bostan, Andreea; Schneider, Walter; Cole, Michael W
2017-02-01
Mapping directions of influence in the human brain connectome represents the next phase in understanding its functional architecture. However, a host of methodological uncertainties have impeded the application of directed connectivity methods, which have primarily been validated via "ground truth" connectivity patterns embedded in simulated functional MRI (fMRI) and magneto-/electro-encephalography (MEG/EEG) datasets. Such simulations rely on many generative assumptions, and we hence utilized a different strategy involving empirical data in which a ground truth directed connectivity pattern could be anticipated with confidence. Specifically, we exploited the established "sensory reactivation" effect in episodic memory, in which retrieval of sensory information reactivates regions involved in perceiving that sensory modality. Subjects performed a paired associate task in separate fMRI and MEG sessions, in which a ground truth reversal in directed connectivity between auditory and visual sensory regions was instantiated across task conditions. This directed connectivity reversal was successfully recovered across different algorithms, including Granger causality and Bayes network (IMAGES) approaches, and across fMRI ("raw" and deconvolved) and source-modeled MEG. These results extend simulation studies of directed connectivity, and offer practical guidelines for the use of such methods in clarifying causal mechanisms of neural processing. Copyright © 2016 Elsevier Inc. All rights reserved.
Simulation of X-ray absorption spectra with orthogonality constrained density functional theory.
Derricotte, Wallace D; Evangelista, Francesco A
2015-06-14
Orthogonality constrained density functional theory (OCDFT) [F. A. Evangelista, P. Shushkov and J. C. Tully, J. Phys. Chem. A, 2013, 117, 7378] is a variational time-independent approach for the computation of electronic excited states. In this work we extend OCDFT to compute core-excited states and generalize the original formalism to determine multiple excited states. Benchmark computations on a set of 13 small molecules and 40 excited states show that unshifted OCDFT/B3LYP excitation energies have a mean absolute error of 1.0 eV. Contrary to time-dependent DFT, OCDFT excitation energies for first- and second-row elements are computed with near-uniform accuracy. OCDFT core excitation energies are insensitive to the choice of the functional and the amount of Hartree-Fock exchange. We show that OCDFT is a powerful tool for the assignment of X-ray absorption spectra of large molecules by simulating the gas-phase near-edge spectrum of adenine and thymine.
Freud, Géza
1971-01-01
Orthogonal Polynomials contains an up-to-date survey of the general theory of orthogonal polynomials. It deals with the problem of polynomials and reveals that the sequence of these polynomials forms an orthogonal system with respect to a non-negative m-distribution defined on the real numerical axis. Comprised of five chapters, the book begins with the fundamental properties of orthogonal polynomials. After discussing the momentum problem, it then explains the quadrature procedure, the convergence theory, and G. Szegő's theory. This book is useful for those who intend to use it as referenc
The effect of loss functions on empirical Bayes reliability analysis
Directory of Open Access Journals (Sweden)
Camara Vincent A. R.
1998-01-01
Full Text Available The aim of the present study is to investigate the sensitivity of empirical Bayes estimates of the reliability function with respect to changing of the loss function. In addition to applying some of the basic analytical results on empirical Bayes reliability obtained with the use of the “popular” squared error loss function, we shall derive some expressions corresponding to empirical Bayes reliability estimates obtained with the Higgins–Tsokos, the Harris and our proposed logarithmic loss functions. The concept of efficiency, along with the notion of integrated mean square error, will be used as a criterion to numerically compare our results. It is shown that empirical Bayes reliability functions are in general sensitive to the choice of the loss function, and that the squared error loss does not always yield the best empirical Bayes reliability estimate.
Directory of Open Access Journals (Sweden)
Edinson Fuentes
2015-06-01
Full Text Available In this paper, we consider perturbations to a sequence of moments associated with an orthogonality linear functional that is represented by a positive measure supported in [−1, 1]. In particular, given a perturbation to such a measure on the real line, we analyze the perturbation obtained on the corresponding measure on the unit circle, when both measures are related through the Szeg´´o transformation. A similar perturbation is analyzed through the inverse Szeg´´o transformation. In both cases, we show that the applied perturbation can be expressed in terms of the singular part of the measures, and also in terms of the corresponding sequences of moments. Resumen. En el presente trabajo, analizamos las perturbaciones a una sucesión de momentos asociada a un funcional lineal de ortogonalidad que se representa por una medida positiva con soporte en [−1, 1]. En particular, dada una cierta perturbación a dicha medida en la recta real, analizamos la perturbación obtenida en la correspondiente medida en la circunferencia unidad, cuando dichas medidas están relacionadas por la transformación de Szeg´´o. También se analiza una perturbación similar a través de la transformación inversa de Szeg´´o. En ambos casos, se muestra que la perturbación aplicada puede ser expresada en términos de la parte singular de las medidas, y también a través de las correspondientes sucesiones de momentos.
International Nuclear Information System (INIS)
McLaughlin, K. T.-R.; Vartanian, A. H.; Zhou, X.
2008-01-01
Orthogonal rational functions are characterized in terms of a family of matrix Riemann-Hilbert problems on R, and a related family of energy minimisation problems is presented. Existence, uniqueness, and regularity properties of the equilibrium measures which solve the energy minimisation problems are established. These measures are used to derive a family of 'model' matrix Riemann-Hilbert problems which are amenable to asymptotic analysis via the Deift-Zhou non-linear steepest-descent method
International Nuclear Information System (INIS)
Carvajal Escobar, Yesid; Marco Segura, Juan B
2005-01-01
An EOF analysis or principal component analysis (PC) was made for monthly precipitation (1972-1998) using 50 stations, and for monthly rate of flow (1951-2000) at 8 stations in the Valle del Cauca state, Colombia. Previously, we had applied 5 measures in order to verify the convenience of the analysis. These measures were: i) evaluation of significance level of correlation between variables; II) the kaiser-Meyer-Oikin (KMO) test; III) the Bartlett sphericity test; (IV) the measurement of sample adequacy (MSA), and v) the percentage of non-redundant residues with absolute values>0.05. For the selection of the significant PCS in every set of variables we applied seven criteria: the graphical method, the explained variance percentage, the mean root, the tests of Velicer, Bartlett, Broken Stich and the cross validation test. We chose the latter as the best one. It is robust and quantitative. Precipitation stations were divided in three homogeneous groups, applying a hierarchical cluster analysis, which was verified through the geographic method and the discriminate analysis for the first four EOFs of precipitation. There are many advantages to the EOF method: reduction of the dimensionality of multivariate data, calculation of missing data, evaluation and reduction of multi-co linearity, building of homogeneous groups, and detection of outliers. With the first four principal components we can explain 60.34% of the total variance of monthly precipitation for the Valle del Cauca state, and 94% of the total variance for the selected records of rates of flow
Kernel empirical orthogonal function analysis of 1992-2008 global sea surface height anomaly data
DEFF Research Database (Denmark)
Nielsen, Allan Aasbjerg; Andersen, Ole Baltazar; Knudsen, Per
2009-01-01
to large scale ocean currents and particularly to the pulsing of the El Niño/Southern Oscillation. Large scale ocean events associated with the El Niño/Southern Oscillation related signals are conveniently concentrated in the first SSH EOF modes. A major difference between the classical linear EOF...
The effect of loss functions on empirical Bayes reliability analysis
Directory of Open Access Journals (Sweden)
Vincent A. R. Camara
1999-01-01
Full Text Available The aim of the present study is to investigate the sensitivity of empirical Bayes estimates of the reliability function with respect to changing of the loss function. In addition to applying some of the basic analytical results on empirical Bayes reliability obtained with the use of the “popular” squared error loss function, we shall derive some expressions corresponding to empirical Bayes reliability estimates obtained with the Higgins–Tsokos, the Harris and our proposed logarithmic loss functions. The concept of efficiency, along with the notion of integrated mean square error, will be used as a criterion to numerically compare our results.
Czech Academy of Sciences Publication Activity Database
Vejchodský, Tomáš; Šolín, Pavel
2008-01-01
Roč. 218, č. 1 (2008), s. 192-200 ISSN 0377-0427 R&D Projects: GA AV ČR IAA100760702; GA ČR GA102/05/0629; GA ČR(CZ) GA102/07/0496 Institutional research plan: CEZ:AV0Z10190503; CEZ:AV0Z20570509 Keywords : static condensation of internal degrees of freedom * orthogonalization * ILU preconditioning Subject RIV: BA - General Mathematics Impact factor: 1.048, year: 2008
Brecht, Hans P.; Ivanov, Vassili; Dumani, Diego S.; Emelianov, Stanislav Y.; Anastasio, Mark A.; Ermilov, Sergey A.
2018-03-01
We have developed a preclinical 3D imaging instrument integrating photoacoustic tomography and fluorescence (PAFT) addressing known deficiencies in sensitivity and spatial resolution of the individual imaging components. PAFT is designed for simultaneous acquisition of photoacoustic and fluorescence orthogonal projections at each rotational position of a biological object, enabling direct registration of the two imaging modalities. Orthogonal photoacoustic projections are utilized to reconstruct large (21 cm3 ) volumes showing vascularized anatomical structures and regions of induced optical contrast with spatial resolution exceeding 100 µm. The major advantage of orthogonal fluorescence projections is significant reduction of background noise associated with transmitted or backscattered photons. The fluorescence imaging component of PAFT is used to boost detection sensitivity by providing low-resolution spatial constraint for the fluorescent biomarkers. PAFT performance characteristics were assessed by imaging optical and fluorescent contrast agents in tissue mimicking phantoms and in vivo. The proposed PAFT technology will enable functional and molecular volumetric imaging using fluorescent biomarkers, nanoparticles, and other photosensitive constructs mapped with high fidelity over robust anatomical structures, such as skin, central and peripheral vasculature, and internal organs.
Ilić, Aleksandar D.; Pavlović, Vlastimir D.
2011-01-01
A new original formulation of all pole low-pass filter functions is proposed in this article. The starting point in solving the approximation problem is a direct application of the Christoffel-Darboux formula for the set of orthogonal polynomials, including Gegenbauer orthogonal polynomials in the finite interval [-1, +1] with the application of a weighting function with a single free parameter. A general solution for the filter functions is obtained in a compact explicit form, which is shown to enable generation of the Gegenbauer filter functions in a simple way by choosing the value of the free parameter. Moreover, the proposed solution with the same criterion of approximation could be used to generate Legendre and Chebyshev filter functions of the first and second kind as well. The examples of proposed filter functions of even (10th) and odd (11th) order are illustrated. The approximation is shown to yield a good compromise solution with respect to the filter frequency characteristics (magnitude as well as phase characteristics). The influence of tolerance of the filter critical component (inductor) on the proposed magnitude and group delay characteristics of a resistively terminated LC lossless ladder filter is analysed as well. The proposed filter functions are superior in terms of the excellent magnitude characteristic, which approximates an ideal filter almost perfectly over the entire pass-band range and exhibits the summed sensitivity function better than that of a Butterworth filter. In the article, we present the filter function solution that exhibits optimum amplitude as well as optimum group delay characteristics that are of crucial importance for implementation of digital processing as well as RF analogue parts of communication networks. Derivation of the other band range filter functions, which could be realised either by continuous or digital filters, is also generally possible with the procedure proposed in this article.
Using Loss Functions for DIF Detection: An Empirical Bayes Approach.
Zwick, Rebecca; Thayer, Dorothy; Lewis, Charles
2000-01-01
Studied a method for flagging differential item functioning (DIF) based on loss functions. Builds on earlier research that led to the development of an empirical Bayes enhancement to the Mantel-Haenszel DIF analysis. Tested the method through simulation and found its performance better than some commonly used DIF classification systems. (SLD)
Uniform convergence of the empirical spectral distribution function
Mikosch, T; Norvaisa, R
1997-01-01
Let X be a linear process having a finite fourth moment. Assume F is a class of square-integrable functions. We consider the empirical spectral distribution function J(n,X) based on X and indexed by F. If F is totally bounded then J(n,X) satisfies a uniform strong law of large numbers. If, in
Some connections for manuals of empirical logic to functional analysis
International Nuclear Information System (INIS)
Cook, T.A.
1981-01-01
In this informal presentation, the theory of manuals of operations is connected with some familiar concepts in functional analysis; namely, base normed and order unit normed spaces. The purpose of this discussion is to present several general open problems which display the interplay of empirical logic with functional analysis. These are mathematical problems with direct physical interpretation. (orig./HSI)
Identifying Similarities in Cognitive Subtest Functional Requirements: An Empirical Approach
Frisby, Craig L.; Parkin, Jason R.
2007-01-01
In the cognitive test interpretation literature, a Rational/Intuitive, Indirect Empirical, or Combined approach is typically used to construct conceptual taxonomies of the functional (behavioral) similarities between subtests. To address shortcomings of these approaches, the functional requirements for 49 subtests from six individually…
Seiwert, Jan; Herzberger, Jana; Leibig, Daniel; Frey, Holger
2017-01-01
The synthesis of thioether-bearing hyperbranched polyether polyols based on an AB/AB 2 type copolymerization (cyclic latent monomers) is introduced. The polymers are prepared by anionic ring-opening multibranching copolymerization of glycidol and 2-(methylthio)ethyl glycidyl ether (MTEGE), which is conveniently accessible in a single etherification step. Slow monomer addition provides control over molecular weights. Moderate dispersities (Đ = 1.48-1.85) are obtained, given the hyperbranched structure. In situ 1 H NMR copolymerization kinetics reveal reactivity ratios of r G = 3.7 and r MTEGE = 0.27. Using slow monomer addition, copolymer composition can be systematically varied, allowing for the adjustment of the hydroxyl/thioether ratio, the degree of branching (DB = 0.36-0.48), thermal properties, and cloud point temperatures in aqueous solution in the range of 29-75 °C. Thioether oxidation to sulfoxides enables to tailor the copolymers' solubility profile. Use of these copolymers as a versatile, multifunctional platform for orthogonal modification is highlighted. The methyl sulfide groups can be selectively alkoxylated, using propylene oxide, allyl glycidyl ether, or furfuryl glycidyl ether, resulting in functional hyperbranched polyelectrolytes. Reaction of the alcohol groups with benzyl isocyanate demonstrates successful orthogonal functionalization. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Functional Measurement in the Field of Empirical Bioethics
Mullet, Etienne; Sorum, Paul C.; Teysseire, Nathalie; Nann, Stephanie; Martinez, Guadalupe Elizabeth Morales; Ahmed, Ramadan; Kamble, Shanmukh; Olivari, Cecilia; Sastre, Maria Teresa Munoz
2012-01-01
We present, in a synthetic way, some of the main findings from five studies that were conducted in the field of empirical bioethics, using the Functional Measurement framework. These studies were about (a) the rationing of rare treatments, (b) adolescents' abortions, (c) end-of-life decision-making regarding damaged neonates, (d) end-of-life…
Piret, Cécile
2012-05-01
Much work has been done on reconstructing arbitrary surfaces using the radial basis function (RBF) method, but one can hardly find any work done on the use of RBFs to solve partial differential equations (PDEs) on arbitrary surfaces. In this paper, we investigate methods to solve PDEs on arbitrary stationary surfaces embedded in . R3 using the RBF method. We present three RBF-based methods that easily discretize surface differential operators. We take advantage of the meshfree character of RBFs, which give us a high accuracy and the flexibility to represent the most complex geometries in any dimension. Two out of the three methods, which we call the orthogonal gradients (OGr) methods are the result of our work and are hereby presented for the first time. © 2012 Elsevier Inc.
Orthogonalization of correlated states
International Nuclear Information System (INIS)
Fantoni, S.; Pandharipande, V.R.
1988-01-01
A scheme for orthogonalizing correlated states while preserving the diagonal matrix elements of the Hamiltonian is developed. Conventional perturbation theory can be used with the orthonormal correlated basis obtained from this scheme. Advantages of using orthonormal correlated states in calculations of the response function and correlation energy are discussed
Orthogonal serialisation for Haskell
DEFF Research Database (Denmark)
Berthold, Jost
2010-01-01
support for parallel Haskell on distributed memory platforms. This serialisation has highly desirable and so-far unrivalled properties: it is truly orthogonal to evaluation and also does not require any type class mechanisms. Especially, (almost) any kind of value can be serialised, including functions...
International Nuclear Information System (INIS)
Puchin, V.E.; Zapol, B.P.
1990-11-01
The authors try to solve the following problems: provided that variation freedom is not restricted and intragroup correlation is taken into account in a given approximation, is it possible to develop for group functions any analogue of the well known (in the case of orbitals) Adams-Gilbert-Kunz method that could give one a possibility to go from delocalized group functions to localized ones seeking for minimization of the intergroup correlation? 20 refs, 1 tab
Li, Ying; Liu, Yi; Gao, Tieren; Zhang, Boce; Song, Yingying; Terrell, Jessica L; Barber, Nathan; Bentley, William E; Takeuchi, Ichiro; Payne, Gregory F; Wang, Qin
2015-05-20
A magnetic nanocomposite film with the capability of reversibly collecting functionalized magnetic particles was fabricated by simultaneously imposing two orthogonal stimuli (electrical and magnetic). We demonstrate that cathodic codeposition of chitosan and Fe3O4 nanoparticles while simultaneously applying a magnetic field during codeposition can (i) organize structure, (ii) confer magnetic properties, and (iii) yield magnetic films that can perform reversible collection/assembly functions. The magnetic field triggered the self-assembly of Fe3O4 nanoparticles into hierarchical "chains" and "fibers" in the chitosan film. For controlled magnetic properties, the Fe3O4-chitosan film was electrodeposited in the presence of various strength magnetic fields and different deposition times. The magnetic properties of the resulting films should enable broad applications in complex devices. As a proof of concept, we demonstrate the reversible capture and release of green fluorescent protein (EGFP)-conjugated magnetic microparticles by the magnetic chitosan film. Moreover, antibody-functionalized magnetic microparticles were applied to capture cells from a sample, and these cells were collected, analyzed, and released by the magnetic chitosan film, paving the way for applications such as reusable biosensor interfaces (e.g., for pathogen detection). To our knowledge, this is the first report to apply a magnetic field during the electrodeposition of a hydrogel to generate magnetic soft matter. Importantly, the simple, rapid, and reagentless fabrication methodologies demonstrated here are valuable features for creating a magnetic device interface.
Mason, A M
2018-01-01
In this paper the authors apply to the zeros of families of L-functions with orthogonal or symplectic symmetry the method that Conrey and Snaith (Correlations of eigenvalues and Riemann zeros, 2008) used to calculate the n-correlation of the zeros of the Riemann zeta function. This method uses the Ratios Conjectures (Conrey, Farmer, and Zimbauer, 2008) for averages of ratios of zeta or L-functions. Katz and Sarnak (Zeroes of zeta functions and symmetry, 1999) conjecture that the zero statistics of families of L-functions have an underlying symmetry relating to one of the classical compact groups U(N), O(N) and USp(2N). Here the authors complete the work already done with U(N) (Conrey and Snaith, Correlations of eigenvalues and Riemann zeros, 2008) to show how new methods for calculating the n-level densities of eigenangles of random orthogonal or symplectic matrices can be used to create explicit conjectures for the n-level densities of zeros of L-functions with orthogonal or symplectic symmetry, including al...
Directory of Open Access Journals (Sweden)
Corrado Dimauro
2010-11-01
Full Text Available Test day records for milk yield of 57,390 first lactation Canadian Holsteins were analyzed with a linear model that included the fixed effects of herd-test date and days in milk (DIM interval nested within age and calving season. Residuals from this model were analyzed as a new variable and fitted with a five parameter model, fourth-order Legendre polynomials, with linear, quadratic and cubic spline models with three knots. The fit of the models was rather poor, with about 30-40% of the curves showing an adjusted R-square lower than 0.20 across all models. Results underline a great difficulty in modelling individual deviations around the mean curve for milk yield. However, the Ali and Schaeffer (5 parameter model and the fourth-order Legendre polynomials were able to detect two basic shapes of individual deviations among the mean curve. Quadratic and, especially, cubic spline functions had better fitting performances but a poor predictive ability due to their great flexibility that results in an abrupt change of the estimated curve when data are missing. Parametric and orthogonal polynomials seem to be robust and affordable under this standpoint.
Directory of Open Access Journals (Sweden)
Feng Jiang
2017-01-01
Full Text Available The complex frequency shifted (CFS perfectly matched layer (PML is proposed for the two-dimensional auxiliary differential equation (ADE finite-difference time-domain (FDTD method combined with Associated Hermite (AH orthogonal functions. According to the property of constitutive parameters of CFS-PML (CPML absorbing boundary conditions (ABCs, the auxiliary differential variables are introduced. And one relationship between field components and auxiliary differential variables is derived. Substituting auxiliary differential variables into CPML ABCs, the other relationship between field components and auxiliary differential variables is derived. Then the matrix equations are obtained, which can be unified with Berenger’s PML (BPML and free space. The electric field expansion coefficients can thus be obtained, respectively. In order to validate the efficiency of the proposed method, one example of wave propagation in two-dimensional free space is calculated using BPML, UPML, and CPML. Moreover, the absorbing effectiveness of the BPML, UPML, and CPML is discussed in a two-dimensional (2D case, and the numerical simulations verify the accuracy and efficiency of the proposed method.
An introduction to orthogonal polynomials
Chihara, Theodore S
1978-01-01
Assuming no further prerequisites than a first undergraduate course in real analysis, this concise introduction covers general elementary theory related to orthogonal polynomials. It includes necessary background material of the type not usually found in the standard mathematics curriculum. Suitable for advanced undergraduate and graduate courses, it is also appropriate for independent study. Topics include the representation theorem and distribution functions, continued fractions and chain sequences, the recurrence formula and properties of orthogonal polynomials, special functions, and some
A new empirical potential energy function for Ar2
Myatt, Philip T.; Dham, Ashok K.; Chandrasekhar, Pragna; McCourt, Frederick R. W.; Le Roy, Robert J.
2018-06-01
A critical re-analysis of all available spectroscopic and virial coefficient data for Ar2 has been used to determine an improved empirical analytic potential energy function that has been 'tuned' to optimise its agreement with viscosity, diffusion and thermal diffusion data, and whose short-range behaviour is in reasonably good agreement with the most recent ab initio calculations for this system. The recommended Morse/long-range potential function is smooth and differentiable at all distances, and incorporates both the correct theoretically predicted long-range behaviour and the correct limiting short-range functional behaviour. The resulting value of the well depth is ? cm-1 and the associated equilibrium distance is re = 3.766 (±0.002) Å, while the 40Ar s-wave scattering length is -714 Å.
Development of an empirical typology of African American family functioning.
Mandara, Jelani; Murray, Carolyn B
2002-09-01
This study empirically identified types of African American families. Adolescents (N = 111) were assessed on family functioning. With cluster analytic methods, 3 types of families were identified. The cohesive-authoritative type was above average on parental education and income, averaged about 2 children, exhibited a high quality of family functioning and high self-esteem in adolescents. The conflictive-authoritarian type had average parental education and income, an average of 2.7 children, exhibited controlling and rigid discipline, and placed a high emphasis on achievement. The defensive-neglectful type was predominately headed by single mothers with below average education and income and averaged about 3 children. Such families displayed chaotic family processes, and adolescents tended to suffer from low self-esteem. The typology exhibited good reliability. The implications of the typology are discussed.
Scattering theory and orthogonal polynomials
International Nuclear Information System (INIS)
Geronimo, J.S.
1977-01-01
The application of the techniques of scattering theory to the study of polynomials orthogonal on the unit circle and a finite segment of the real line is considered. The starting point is the recurrence relations satisfied by the polynomials instead of the orthogonality condition. A set of two two terms recurrence relations for polynomials orthogonal on the real line is presented and used. These recurrence relations play roles analogous to those satisfied by polynomials orthogonal on unit circle. With these recurrence formulas a Wronskian theorem is proved and the Christoffel-Darboux formula is derived. In scattering theory a fundamental role is played by the Jost function. An analogy is deferred of this function and its analytic properties and the locations of its zeros investigated. The role of the analog Jost function in various properties of these orthogonal polynomials is investigated. The techniques of inverse scattering theory are also used. The discrete analogues of the Gelfand-Levitan and Marchenko equations are derived and solved. These techniques are used to calculate asymptotic formulas for the orthogonal polynomials. Finally Szego's theorem on toeplitz and Hankel determinants is proved using the recurrence formulas and some properties of the Jost function. The techniques of inverse scattering theory are used to calculate the correction terms
Orthogonal Multiwavelet Frames in L2Rd
Directory of Open Access Journals (Sweden)
Liu Zhanwei
2012-01-01
Full Text Available We characterize the orthogonal frames and orthogonal multiwavelet frames in L2Rd with matrix dilations of the form (Df(x=detAf(Ax, where A is an arbitrary expanding d×d matrix with integer coefficients. Firstly, through two arbitrarily multiwavelet frames, we give a simple construction of a pair of orthogonal multiwavelet frames. Then, by using the unitary extension principle, we present an algorithm for the construction of arbitrarily many orthogonal multiwavelet tight frames. Finally, we give a general construction algorithm for orthogonal multiwavelet tight frames from a scaling function.
Non-empirical energy density functional for the nuclear structure
International Nuclear Information System (INIS)
Rot ival, V.
2008-09-01
The energy density functional (EDF) formalism is the tool of choice for large-scale low-energy nuclear structure calculations both for stable experimentally known nuclei whose properties are accurately reproduced and systems that are only theoretically predicted. We highlight in the present dissertation the capability of EDF methods to tackle exotic phenomena appearing at the very limits of stability, that is the formation of nuclear halos. We devise a new quantitative and model-independent method that characterizes the existence and properties of halos in medium- to heavy-mass nuclei, and quantifies the impact of pairing correlations and the choice of the energy functional on the formation of such systems. These results are found to be limited by the predictive power of currently-used EDFs that rely on fitting to known experimental data. In the second part of this dissertation, we initiate the construction of non-empirical EDFs that make use of the new paradigm for vacuum nucleon-nucleon interactions set by so-called low-momentum interactions generated through the application of renormalization group techniques. These soft-core vacuum potentials are used as a step-stone of a long-term strategy which connects modern many-body techniques and EDF methods. We provide guidelines for designing several non-empirical models that include in-medium many-body effects at various levels of approximation, and can be handled in state-of-the art nuclear structure codes. In the present work, the first step is initiated through the adjustment of an operator representation of low-momentum vacuum interactions using a custom-designed parallel evolutionary algorithm. The first results highlight the possibility to grasp most of the relevant physics for low-energy nuclear structure using this numerically convenient Gaussian vertex. (author)
Production functions for climate policy modeling. An empirical analysis
International Nuclear Information System (INIS)
Van der Werf, Edwin
2008-01-01
Quantitative models for climate policy modeling differ in the production structure used and in the sizes of the elasticities of substitution. The empirical foundation for both is generally lacking. This paper estimates the parameters of 2-level CES production functions with capital, labour and energy as inputs, and is the first to systematically compare all nesting structures. Using industry-level data from 12 OECD countries, we find that the nesting structure where capital and labour are combined first, fits the data best, but for most countries and industries we cannot reject that all three inputs can be put into one single nest. These two nesting structures are used by most climate models. However, while several climate policy models use a Cobb-Douglas function for (part of the) production function, we reject elasticities equal to one, in favour of considerably smaller values. Finally we find evidence for factor-specific technological change. With lower elasticities and with factor-specific technological change, some climate policy models may find a bigger effect of endogenous technological change on mitigating the costs of climate policy. (author)
2011-10-01
mail: gaelle.casagrande@dga.defense.gouv.fr). Y. Stephan is with the Service Hydrographique et Oceanographique de la Marine (SHOM), Brest 29200...the two first modes of the EOF analysis. In black, original data temperature profiles. The profiles are located on the expansion coefficient scatter...in 2000, the M.Sc. degree in oceanography, £ H meteorology, and environment from the University de Jussieu, Paris , France, in 2002, and the
Estimation of Cumulative Absolute Velocity using Empirical Green's Function Method
International Nuclear Information System (INIS)
Park, Dong Hee; Yun, Kwan Hee; Chang, Chun Joong; Park, Se Moon
2009-01-01
In recognition of the needs to develop a new criterion for determining when the OBE (Operating Basis Earthquake) has been exceeded at nuclear power plants, Cumulative Absolute Velocity (CAV) was introduced by EPRI. The concept of CAV is the area accumulation with the values more than 0.025g occurred during every one second. The equation of the CAV is as follows. CAV = ∫ 0 max |a(t)|dt (1) t max = duration of record, a(t) = acceleration (>0.025g) Currently, the OBE exceedance criteria in Korea is Peak Ground Acceleration (PGA, PGA>0.1g). When Odesan earthquake (M L =4.8, January 20th, 2007) and Gyeongju earthquake (M L =3.4, June 2nd, 1999) were occurred, we have had already experiences of PGA greater than 0.1g that did not even cause any damage to the poorly-designed structures nearby. This moderate earthquake has motivated Korea to begin the use of the CAV for OBE exceedance criteria for NPPs. Because the present OBE level has proved itself to be a poor indicator for small-to-moderate earthquakes, for which the low OBE level can cause an inappropriate shut down the plant. A more serious possibility is that this scenario will become a reality at a very high level. Empirical Green's Function method was a simulation technique which can estimate the CAV value and it is hereby introduced
Definite Integrals using Orthogonality and Integral Transforms
Directory of Open Access Journals (Sweden)
Howard S. Cohl
2012-10-01
Full Text Available We obtain definite integrals for products of associated Legendre functions with Bessel functions, associated Legendre functions, and Chebyshev polynomials of the first kind using orthogonality and integral transforms.
Empirical Green's function analysis: Taking the next step
Hough, S.E.
1997-01-01
An extension of the empirical Green's function (EGF) method is presented that involves determination of source parameters using standard EGF deconvolution, followed by inversion for a common attenuation parameter for a set of colocated events. Recordings of three or more colocated events can thus be used to constrain a single path attenuation estimate. I apply this method to recordings from the 1995-1996 Ridgecrest, California, earthquake sequence; I analyze four clusters consisting of 13 total events with magnitudes between 2.6 and 4.9. I first obtain corner frequencies, which are used to infer Brune stress drop estimates. I obtain stress drop values of 0.3-53 MPa (with all but one between 0.3 and 11 MPa), with no resolved increase of stress drop with moment. With the corner frequencies constrained, the inferred attenuation parameters are very consistent; they imply an average shear wave quality factor of approximately 20-25 for alluvial sediments within the Indian Wells Valley. Although the resultant spectral fitting (using corner frequency and ??) is good, the residuals are consistent among the clusters analyzed. Their spectral shape is similar to the the theoretical one-dimensional response of a layered low-velocity structure in the valley (an absolute site response cannot be determined by this method, because of an ambiguity between absolute response and source spectral amplitudes). I show that even this subtle site response can significantly bias estimates of corner frequency and ??, if it is ignored in an inversion for only source and path effects. The multiple-EGF method presented in this paper is analogous to a joint inversion for source, path, and site effects; the use of colocated sets of earthquakes appears to offer significant advantages in improving resolution of all three estimates, especially if data are from a single site or sites with similar site response.
Tarumi, Moto; Kobayashi, Masato; Nakai, Hiromi
2012-11-13
The antisymmetric product of strongly orthogonal geminals (APSG) method is a wave function theory that can effectively treat the static electron correlation. Recently, we proposed the open-shell APSG method using one-electron orbitals for open-shell parts. In this paper, we have extended the perturbation correction to the open-shell APSG calculations through Møller-Plesset-type multiconfiguration perturbation theory (MP-MCPT). Numerical applications demonstrate that the present open-shell MP-MCPT can reasonably reproduce the dissociation energies or equilibrium distances for open-shell systems.
Deb, Anish; Sarkar, Gautam
2016-01-01
This book introduces a new set of orthogonal hybrid functions (HF) which approximates time functions in a piecewise linear manner which is very suitable for practical applications. The book presents an analysis of different systems namely, time-invariant system, time-varying system, multi-delay systems---both homogeneous and non-homogeneous type- and the solutions are obtained in the form of discrete samples. The book also investigates system identification problems for many of the above systems. The book is spread over 15 chapters and contains 180 black and white figures, 18 colour figures, 85 tables and 56 illustrative examples. MATLAB codes for many such examples are included at the end of the book.
Julia Sets of Orthogonal Polynomials
DEFF Research Database (Denmark)
Christiansen, Jacob Stordal; Henriksen, Christian; Petersen, Henrik Laurberg
2018-01-01
For a probability measure with compact and non-polar support in the complex plane we relate dynamical properties of the associated sequence of orthogonal polynomials fPng to properties of the support. More precisely we relate the Julia set of Pn to the outer boundary of the support, the lled Julia...... set to the polynomial convex hull K of the support, and the Green's function associated with Pn to the Green's function for the complement of K....
Shepard, Ron; Gidofalvi, Gergely; Brozell, Scott R.
2014-08-01
Practical algorithms are presented for the parameterization of orthogonal matrices Q ∈ {R} m×n in terms of the minimal number of essential parameters {φ}. Both square n = m and rectangular n applications such as the representation of the arc factors in the multifacet graphically contracted function method and the representation of orbital coefficients in SCF and DFT methods. The parameterizations are represented formally using products of elementary Householder reflector matrices. Standard mathematical libraries, such as LAPACK, may be used to perform the basic low-level factorization, reduction, and other algebraic operations. Some care must be taken with the choice of phase factors in order to ensure stability and continuity. The transformation of gradient arrays between the Q and {φ} parameterizations is also considered. Operation counts for all factorizations and transformations are determined. Numerical results are presented which demonstrate the robustness, stability, and accuracy of these algorithms.
On the Reliability of Source Time Functions Estimated Using Empirical Green's Function Methods
Gallegos, A. C.; Xie, J.; Suarez Salas, L.
2017-12-01
The Empirical Green's Function (EGF) method (Hartzell, 1978) has been widely used to extract source time functions (STFs). In this method, seismograms generated by collocated events with different magnitudes are deconvolved. Under a fundamental assumption that the STF of the small event is a delta function, the deconvolved Relative Source Time Function (RSTF) yields the large event's STF. While this assumption can be empirically justified by examination of differences in event size and frequency content of the seismograms, there can be a lack of rigorous justification of the assumption. In practice, a small event might have a finite duration when the RSTF is retrieved and interpreted as the large event STF with a bias. In this study, we rigorously analyze this bias using synthetic waveforms generated by convolving a realistic Green's function waveform with pairs of finite-duration triangular or parabolic STFs. The RSTFs are found using a time-domain based matrix deconvolution. We find when the STFs of smaller events are finite, the RSTFs are a series of narrow non-physical spikes. Interpreting these RSTFs as a series of high-frequency source radiations would be very misleading. The only reliable and unambiguous information we can retrieve from these RSTFs is the difference in durations and the moment ratio of the two STFs. We can apply a Tikhonov smoothing to obtain a single-pulse RSTF, but its duration is dependent on the choice of weighting, which may be subjective. We then test the Multi-Channel Deconvolution (MCD) method (Plourde & Bostock, 2017) which assumes that both STFs have finite durations to be solved for. A concern about the MCD method is that the number of unknown parameters is larger, which would tend to make the problem rank-deficient. Because the kernel matrix is dependent on the STFs to be solved for under a positivity constraint, we can only estimate the rank-deficiency with a semi-empirical approach. Based on the results so far, we find that the
An Empirical Assessment of the Form of Utility Functions
Kirby, Kris N.
2011-01-01
Utility functions, which relate subjective value to physical attributes of experience, are fundamental to most decision theories. Seven experiments were conducted to test predictions of the most widely assumed mathematical forms of utility (power, log, and negative exponential), and a function proposed by Rachlin (1992). For pairs of gambles for…
Effective Results Analysis for the Similar Software Products’ Orthogonality
Directory of Open Access Journals (Sweden)
Ion Ivan
2009-10-01
Full Text Available It is defined the concept of similar software. There are established conditions of archiving the software components. It is carried out the orthogonality evaluation and the correlation between the orthogonality and the complexity of the homogenous software components is analyzed. Shall proceed to build groups of similar software products, belonging to the orthogonality intervals. There are presented in graphical form the results of the analysis. There are detailed aspects of the functioning of the software product allocated for the orthogonality.
Simultaneous orthogonal plane imaging.
Mickevicius, Nikolai J; Paulson, Eric S
2017-11-01
Intrafraction motion can result in a smearing of planned external beam radiation therapy dose distributions, resulting in an uncertainty in dose actually deposited in tissue. The purpose of this paper is to present a pulse sequence that is capable of imaging a moving target at a high frame rate in two orthogonal planes simultaneously for MR-guided radiotherapy. By balancing the zero gradient moment on all axes, slices in two orthogonal planes may be spatially encoded simultaneously. The orthogonal slice groups may be acquired with equal or nonequal echo times. A Cartesian spoiled gradient echo simultaneous orthogonal plane imaging (SOPI) sequence was tested in phantom and in vivo. Multiplexed SOPI acquisitions were performed in which two parallel slices were imaged along two orthogonal axes simultaneously. An autocalibrating phase-constrained 2D-SENSE-GRAPPA (generalized autocalibrating partially parallel acquisition) algorithm was implemented to reconstruct the multiplexed data. SOPI images without intraslice motion artifacts were reconstructed at a maximum frame rate of 8.16 Hz. The 2D-SENSE-GRAPPA reconstruction separated the parallel slices aliased along each orthogonal axis. The high spatiotemporal resolution provided by SOPI has the potential to be beneficial for intrafraction motion management during MR-guided radiation therapy or other MRI-guided interventions. Magn Reson Med 78:1700-1710, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.
Aggregate Production Function and Income Identity - Empirical Analysis
Czech Academy of Sciences Publication Activity Database
Čadil, J.; Vltavská, K.; Krejčí, I.; Hartman, David; Brabec, Marek
2017-01-01
Roč. 6, č. 1 (2017), s. 1-17 ISSN 1804-9796 Institutional support: RVO:67985807 Keywords : aggregate production function * income identity * capital services * labour services Subject RIV: BB - Applied Statistics, Operational Research OBOR OECD: Statistics and probability http://www.iises.net/international-journal-of- economic -sciences/publication-detail-1223
Fourier series and orthogonal polynomials
Jackson, Dunham
2004-01-01
This text for undergraduate and graduate students illustrates the fundamental simplicity of the properties of orthogonal functions and their developments in related series. Starting with a definition and explanation of the elements of Fourier series, the text follows with examinations of Legendre polynomials and Bessel functions. Boundary value problems consider Fourier series in conjunction with Laplace's equation in an infinite strip and in a rectangle, with a vibrating string, in three dimensions, in a sphere, and in other circumstances. An overview of Pearson frequency functions is followe
International Nuclear Information System (INIS)
Cresti, Alessandro; Grosso, Giuseppe; Parravicini, Giuseppe Pastori
2006-01-01
We have derived closed analytic expressions for the Green's function of an electron in a two-dimensional electron gas threaded by a uniform perpendicular magnetic field, also in the presence of a uniform electric field and of a parabolic spatial confinement. A workable and powerful numerical procedure for the calculation of the Green's functions for a large infinitely extended quantum wire is considered exploiting a lattice model for the wire, the tight-binding representation for the corresponding matrix Green's function, and the Peierls phase factor in the Hamiltonian hopping matrix element to account for the magnetic field. The numerical evaluation of the Green's function has been performed by means of the decimation-renormalization method, and quite satisfactorily compared with the analytic results worked out in this paper. As an example of the versatility of the numerical and analytic tools here presented, the peculiar semilocal character of the magnetic Green's function is studied in detail because of its basic importance in determining magneto-transport properties in mesoscopic systems
Developing empirical collapse fragility functions for global building types
Jaiswal, K.; Wald, D.; D'Ayala, D.
2011-01-01
Building collapse is the dominant cause of casualties during earthquakes. In order to better predict human fatalities, the U.S. Geological Survey’s Prompt Assessment of Global Earthquakes for Response (PAGER) program requires collapse fragility functions for global building types. The collapse fragility is expressed as the probability of collapse at discrete levels of the input hazard defined in terms of macroseismic intensity. This article provides a simple procedure for quantifying collapse fragility using vulnerability criteria based on the European Macroseismic Scale (1998) for selected European building types. In addition, the collapse fragility functions are developed for global building types by fitting the beta distribution to the multiple experts’ estimates for the same building type (obtained from EERI’s World Housing Encyclopedia (WHE)-PAGER survey). Finally, using the collapse probability distributions at each shaking intensity level as a prior and field-based collapse-rate observations as likelihood, it is possible to update the collapse fragility functions for global building types using the Bayesian procedure.
Piret, Cé cile
2012-01-01
Much work has been done on reconstructing arbitrary surfaces using the radial basis function (RBF) method, but one can hardly find any work done on the use of RBFs to solve partial differential equations (PDEs) on arbitrary surfaces. In this paper
Morphology and function in the empirical analysis of reading adjustment
Directory of Open Access Journals (Sweden)
Carpio, Claudio
2010-06-01
Full Text Available The present study evaluated the effects of varying the criterion and the morphology of the percentage of correct response upon reading adjustment tasks. Participants were 20 voluntary students, distributed in four groups, which were differentiated by the certainty - variability of the criterion and the certainty - variability of the morphology of response to satisfy the criterion. All participants were exposed to a first evaluation, training and finally a second evaluation similar to the first one was applied. Results question the role of morphology as a comprehension strategy independent of a functional criterion, domain and of the text itself
Beam brightness calculation for analytical and empirical distribution functions
International Nuclear Information System (INIS)
Myers, T.J.; Boulais, K.A.; O, Y.S.; Rhee, M.J.
1992-01-01
The beam brightness, a figure of merit for a beam quality useful for high-current low-emittance beams, was introduced by van Steenbergen as B = I/V 4 , where I is the beam current and V 4 is the hypervolume in the four-dimensional trace space occupied by the beam particles. Customarily, the brightness is expressed in terms of the product of emittances ε x ε y as B = ηI/(π 2 ε x ε y ), where η is a form factor of order unity which depends on the precise definition of emittance and hypervolume. Recently, a refined definition of the beam brightness based on the arithmetic mean value defined in statistics is proposed. The beam brightness is defined as B triple-bond 4 > = I -1 ∫ ρ 4 2 dxdydx'dy', where I is the beam current given by I ∫ ρ 4 dxdydx'dy'. Note that in this definition, neither the hypervolume V 4 nor the emittance, are explicitly used; the brightness is determined solely by the distribution function. Brightnesses are unambiguously calculated and expressed analytically in terms of the respective beam current and effective emittance for a few commonly used distribution functions, including Maxwellian and water-bag distributions. Other distributions of arbitrary shape frequently encountered in actual experiments are treated numerically. The resulting brightnesses are expressed in the form B = ηI/(π 2 ε x ε y ), and η is found to be weakly dependent on the form of velocity distribution as well as spatial distribution
Orthogonality and Dimensionality
Directory of Open Access Journals (Sweden)
Olivier Brunet
2013-12-01
Full Text Available In this article, we present what we believe to be a simple way to motivate the use of Hilbert spaces in quantum mechanics. To achieve this, we study the way the notion of dimension can, at a very primitive level, be defined as the cardinality of a maximal collection of mutually orthogonal elements (which, for instance, can be seen as spatial directions. Following this idea, we develop a formalism based on two basic ingredients, namely an orthogonality relation and matroids which are a very generic algebraic structure permitting to define a notion of dimension. Having obtained what we call orthomatroids, we then show that, in high enough dimension, the basic constituants of orthomatroids (more precisely the simple and irreducible ones are isomorphic to generalized Hilbert lattices, so that their presence is a direct consequence of an orthogonality-based characterization of dimension.
Xie, J.; Schaff, D. P.; Chen, Y.; Schult, F.
2013-12-01
Reliably estimated source time functions (STFs) from high-frequency regional waveforms, such as Lg, Pn and Pg, provide important input for seismic source studies, explosion detection and discrimination, and minimization of parameter trade-off in attenuation studies. We have searched for candidate pairs of larger and small earthquakes in and around China that share the same focal mechanism but significantly differ in magnitudes, so that the empirical Green's function (EGF) method can be applied to study the STFs of the larger events. We conducted about a million deconvolutions using waveforms from 925 earthquakes, and screened the deconvolved traces to exclude those that are from event pairs that involved different mechanisms. Only 2,700 traces passed this screening and could be further analyzed using the EGF method. We have developed a series of codes for speeding up the final EGF analysis by implementing automations and user-graphic interface procedures. The codes have been fully tested with a subset of screened data and we are currently applying them to all the screened data. We will present a large number of deconvolved STFs retrieved using various phases (Lg, Pn, Sn and Pg and coda) with information on any directivities, any possible dependence of pulse durations on the wave types, on scaling relations for the pulse durations and event sizes, and on the estimated source static stress drops.
Introduction to Real Orthogonal Polynomials
1992-06-01
uses Green’s functions. As motivation , consider the Dirichlet problem for the unit circle in the plane, which involves finding a harmonic function u(r...xv ; a, b ; q) - TO [q-N ab+’q ; q, xq b. Orthogoy RMotion O0 (bq :q)x p.(q* ; a, b ; q) pg(q’ ; a, b ; q) (q "q), (aq)x (q ; q), (I -abq) (bq ; q... motivation and justi- fication for continued study of the intrinsic structure of orthogonal polynomials. 99 LIST OF REFERENCES 1. Deyer, W. M., ed., CRC
Talebpour, Zahra; Tavallaie, Roya; Ahmadi, Seyyed Hamid; Abdollahpour, Assem
2010-09-01
In this study, a new method for the simultaneous determination of penicillin G salts in pharmaceutical mixture via FT-IR spectroscopy combined with chemometrics was investigated. The mixture of penicillin G salts is a complex system due to similar analytical characteristics of components. Partial least squares (PLS) and radial basis function-partial least squares (RBF-PLS) were used to develop the linear and nonlinear relation between spectra and components, respectively. The orthogonal signal correction (OSC) preprocessing method was used to correct unexpected information, such as spectral overlapping and scattering effects. In order to compare the influence of OSC on PLS and RBF-PLS models, the optimal linear (PLS) and nonlinear (RBF-PLS) models based on conventional and OSC preprocessed spectra were established and compared. The obtained results demonstrated that OSC clearly enhanced the performance of both RBF-PLS and PLS calibration models. Also in the case of some nonlinear relation between spectra and component, OSC-RBF-PLS gave satisfactory results than OSC-PLS model which indicated that the OSC was helpful to remove extrinsic deviations from linearity without elimination of nonlinear information related to component. The chemometric models were tested on an external dataset and finally applied to the analysis commercialized injection product of penicillin G salts.
Verma, Prakash; Derricotte, Wallace D; Evangelista, Francesco A
2016-01-12
Orthogonality constrained density functional theory (OCDFT) provides near-edge X-ray absorption (NEXAS) spectra of first-row elements within one electronvolt from experimental values. However, with increasing atomic number, scalar relativistic effects become the dominant source of error in a nonrelativistic OCDFT treatment of core-valence excitations. In this work we report a novel implementation of the spin-free exact-two-component (X2C) one-electron treatment of scalar relativistic effects and its combination with a recently developed OCDFT approach to compute a manifold of core-valence excited states. The inclusion of scalar relativistic effects in OCDFT reduces the mean absolute error of second-row elements core-valence excitations from 10.3 to 2.3 eV. For all the excitations considered, the results from X2C calculations are also found to be in excellent agreement with those from low-order spin-free Douglas-Kroll-Hess relativistic Hamiltonians. The X2C-OCDFT NEXAS spectra of three organotitanium complexes (TiCl4, TiCpCl3, TiCp2Cl2) are in very good agreement with unshifted experimental results and show a maximum absolute error of 5-6 eV. In addition, a decomposition of the total transition dipole moment into partial atomic contributions is proposed and applied to analyze the nature of the Ti pre-edge transitions in the three organotitanium complexes.
Towards orthogonal Haskell data serialisation
DEFF Research Database (Denmark)
Berthold, Jost
2010-01-01
This paper investigates a novel approach to serialisation of Haskell data structures with a high degree of flexibility, based on runtime support for parallel Haskell on distributed memory platforms. This serialisation has highly desirable and so-far unrivalled properties: it is truly orthogonal...... to evaluation and does not require any type class mechanisms. Especially, (almost) any kind of value can be serialised, including functions and IO actions. We outline the runtime support on which our serialisation is based, and present different versions of the wrapper code in Haskell which can ensure type...
Orthogonality catastrophe and fractional exclusion statistics
Ares, Filiberto; Gupta, Kumar S.; de Queiroz, Amilcar R.
2018-02-01
We show that the N -particle Sutherland model with inverse-square and harmonic interactions exhibits orthogonality catastrophe. For a fixed value of the harmonic coupling, the overlap of the N -body ground state wave functions with two different values of the inverse-square interaction term goes to zero in the thermodynamic limit. When the two values of the inverse-square coupling differ by an infinitesimal amount, the wave function overlap shows an exponential suppression. This is qualitatively different from the usual power law suppression observed in the Anderson's orthogonality catastrophe. We also obtain an analytic expression for the wave function overlaps for an arbitrary set of couplings, whose properties are analyzed numerically. The quasiparticles constituting the ground state wave functions of the Sutherland model are known to obey fractional exclusion statistics. Our analysis indicates that the orthogonality catastrophe may be valid in systems with more general kinds of statistics than just the fermionic type.
Daneva, Maia
2014-01-01
This paper is an empirical study on the application of Function Points (FP) and a FP-based reuse measurement model in Enterprise Resource Planning (ERP) projects in three organizations in the telecommunication sector. The findings of the study are used to compare the requirements reuse for one
Effective Results Analysis for the Similar Software Products’ Orthogonality
Ion Ivan; Daniel Milodin
2009-01-01
It is defined the concept of similar software. There are established conditions of archiving the software components. It is carried out the orthogonality evaluation and the correlation between the orthogonality and the complexity of the homogenous software components is analyzed. Shall proceed to build groups of similar software products, belonging to the orthogonality intervals. There are presented in graphical form the results of the analysis. There are detailed aspects of the functioning o...
The Empirical Definition of the Function of Advertising Costs in E-Commerce
Pursky Oleg I.; Moroz Iryna O.; Mazoha Dmytro P.
2017-01-01
In the publication, an empirical study of the advertising costs in the e-commerce market is carried out. In order to determine the type of functional dependency of advertising costs, dynamics of advertising costs in the e-commerce markets of the US, the world, and Ukraine were researched, followed by an approximation of the series of statistical data on the Internet advertising costs. There is a functional dependency on the Internet advertising costs in the form of a power function with two c...
International Nuclear Information System (INIS)
Matsuoka, Daisuke; Nakasako, Masayoshi
2013-01-01
Highlights: ► Empirical distribution functions of water molecules in protein hydration are made. ► The functions measure how hydrogen-bond geometry in hydration deviate from ideal. ► The functions assess experimentally identified hydration structures of protein. - Abstract: To quantitatively characterize hydrogen-bond geometry in local hydration structures of proteins, we constructed a set of empirical hydration distribution functions (EHDFs) around polar protein atoms in the main and side chains of 11 types of hydrophilic amino acids (D. Matsuoka, M. Nakasako, Journal of Physical Chemistry B 113 (2009) 11274). The functions are the ensemble average of possible hydration patterns around the polar atoms, and describe the anisotropic deviations from ideal hydrogen bond geometry. In addition, we defined probability distribution function of hydration water molecules (PDFH) over the hydrophilic surface of a protein as the sum of EHDFs of solvent accessible polar protein atoms. The functions envelop most of hydration sites identified in crystal structures of proteins (D. Matsuoka, M. Nakasako, Journal of Physical Chemistry B 114 (2010) 4652). Here we propose the application of EHDFs and PDFHs for assessing crystallographically identified hydration structures of proteins. First, hydration water molecules are classified with respect to the geometry in hydrogen bonds in referring EHDFs. Difference Fourier electron density map weighted by PDFH of protein is proposed to identify easily density peaks as candidates of hydration water molecules. A computer program implementing those ideas was developed and used for assessing hydration structures of proteins
Modeling the NPE with finite sources and empirical Green`s functions
Energy Technology Data Exchange (ETDEWEB)
Hutchings, L.; Kasameyer, P.; Goldstein, P. [Lawrence Livermore National Lab., CA (United States)] [and others
1994-12-31
In order to better understand the source characteristics of both nuclear and chemical explosions for purposes of discrimination, we have modeled the NPE chemical explosion as a finite source and with empirical Green`s functions. Seismograms are synthesized at four sties to test the validity of source models. We use a smaller chemical explosion detonated in the vicinity of the working point to obtain empirical Green`s functions. Empirical Green`s functions contain all the linear information of the geology along the propagation path and recording site, which are identical for chemical or nuclear explosions, and therefore reduce the variability in modeling the source of the larger event. We further constrain the solution to have the overall source duration obtained from point-source deconvolution results. In modeling the source, we consider both an elastic source on a spherical surface and an inelastic expanding spherical volume source. We found that the spherical volume solution provides better fits to observed seismograms. The potential to identify secondary sources was examined, but the resolution is too poor to be definitive.
VMF3/GPT3: refined discrete and empirical troposphere mapping functions
Landskron, Daniel; Böhm, Johannes
2018-04-01
Incorrect modeling of troposphere delays is one of the major error sources for space geodetic techniques such as Global Navigation Satellite Systems (GNSS) or Very Long Baseline Interferometry (VLBI). Over the years, many approaches have been devised which aim at mapping the delay of radio waves from zenith direction down to the observed elevation angle, so-called mapping functions. This paper contains a new approach intended to refine the currently most important discrete mapping function, the Vienna Mapping Functions 1 (VMF1), which is successively referred to as Vienna Mapping Functions 3 (VMF3). It is designed in such a way as to eliminate shortcomings in the empirical coefficients b and c and in the tuning for the specific elevation angle of 3°. Ray-traced delays of the ray-tracer RADIATE serve as the basis for the calculation of new mapping function coefficients. Comparisons of modeled slant delays demonstrate the ability of VMF3 to approximate the underlying ray-traced delays more accurately than VMF1 does, in particular at low elevation angles. In other words, when requiring highest precision, VMF3 is to be preferable to VMF1. Aside from revising the discrete form of mapping functions, we also present a new empirical model named Global Pressure and Temperature 3 (GPT3) on a 5°× 5° as well as a 1°× 1° global grid, which is generally based on the same data. Its main components are hydrostatic and wet empirical mapping function coefficients derived from special averaging techniques of the respective (discrete) VMF3 data. In addition, GPT3 also contains a set of meteorological quantities which are adopted as they stand from their predecessor, Global Pressure and Temperature 2 wet. Thus, GPT3 represents a very comprehensive troposphere model which can be used for a series of geodetic as well as meteorological and climatological purposes and is fully consistent with VMF3.
Theoretical Models for Orthogonal Cutting
DEFF Research Database (Denmark)
De Chiffre, Leonardo
This review of simple models for orthogonal cutting was extracted from: “L. De Chiffre: Metal Cutting Mechanics and Applications, D.Sc. Thesis, Technical University of Denmark, 1990.”......This review of simple models for orthogonal cutting was extracted from: “L. De Chiffre: Metal Cutting Mechanics and Applications, D.Sc. Thesis, Technical University of Denmark, 1990.”...
Orthogonal Algorithm of Logic Probability and Syndrome-Testable Analysis
Institute of Scientific and Technical Information of China (English)
无
1990-01-01
A new method,orthogonal algoritm,is presented to compute the logic probabilities(i.e.signal probabilities)accurately,The transfer properties of logic probabilities are studied first,which are useful for the calculation of logic probability of the circuit with random independent inputs.Then the orthogonal algoritm is described to compute the logic probability of Boolean function realized by a combinational circuit.This algorithm can make Boolean function “ORTHOGONAL”so that the logic probabilities can be easily calculated by summing up the logic probabilities of all orthogonal terms of the Booleam function.
International Nuclear Information System (INIS)
Li, Longqiu; Xu, Ming; Song, Wenping; Ovcharenko, Andrey; Zhang, Guangyu; Jia, Ding
2013-01-01
Empirical potentials have a strong effect on the hybridization and structure of amorphous carbon and are of great importance in molecular dynamics (MD) simulations. In this work, amorphous carbon at densities ranging from 2.0 to 3.2 g/cm 3 was modeled by a liquid quenching method using Tersoff, 2nd REBO, and ReaxFF empirical potentials. The hybridization, structure and radial distribution function G(r) of carbon atoms were analyzed as a function of the three potentials mentioned above. The ReaxFF potential is capable to model the change of the structure of amorphous carbon and MD results are in a good agreement with experimental results and density function theory (DFT) at low density of 2.6 g/cm 3 and below. The 2nd REBO potential can be used when amorphous carbon has a very low density of 2.4 g/cm 3 and below. Considering the computational efficiency, the Tersoff potential is recommended to model amorphous carbon at a high density of 2.6 g/cm 3 and above. In addition, the influence of the quenching time on the hybridization content obtained with the three potentials is discussed.
Chen, Ying-Ju; Ning, Wei; Gupta, Arjun K
2016-05-01
The mean residual life (MRL) function is one of the basic parameters of interest in survival analysis that describes the expected remaining time of an individual after a certain age. The study of changes in the MRL function is practical and interesting because it may help us to identify some factors such as age and gender that may influence the remaining lifetimes of patients after receiving a certain surgery. In this paper, we propose a detection procedure based on the empirical likelihood for the changes in MRL functions with right censored data. Two real examples are also given: Veterans' administration lung cancer study and Stanford heart transplant to illustrate the detecting procedure. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
Directory of Open Access Journals (Sweden)
Denise Garcia de Santana
2002-06-01
the statistical systems, mainly when a high unbalancing degree is present. Taking that into account, the objective of this work is focused on the study of the estimable functions and of the testable hypotheses in orthogonal and partially orthogonal designs with three factors. For the main effects, in which the generated subspace is individually orthogonal to the inherent subspaces to the other factors, are estimable and, therefore, the corresponding hypothesis is testable in models with no interactions. When interactions are present, the estimable functions present besides the parameters of the factor itself, parameters of the interactions in which the factor is present. In these cases, whether the model contains or not interactions, the hypotheses on weighted averages (type I are equivalent to the hypothesis on proportional averages (type II and, since the complete term is imperative for both full and partial orthogonalities, the equivalence between the hypotheses on non-proportional averages (types III and IV also occurs. The equity between the hypotheses of the types I and II occurs in all interactions, in the orthogonal designs and, in the partially orthogonal designs, it also occurs in the interactions formed by the factors that were not orthogonal between themselves. In these interactions the estimable functions present parameters of the interaction itself, including parameters of the interactions of degree three.
Many-body orthogonal polynomial systems
International Nuclear Information System (INIS)
Witte, N.S.
1997-03-01
The fundamental methods employed in the moment problem, involving orthogonal polynomial systems, the Lanczos algorithm, continued fraction analysis and Pade approximants has been combined with a cumulant approach and applied to the extensive many-body problem in physics. This has yielded many new exact results for many-body systems in the thermodynamic limit - for the ground state energy, for excited state gaps, for arbitrary ground state avenges - and are of a nonperturbative nature. These results flow from a confluence property of the three-term recurrence coefficients arising and define a general class of many-body orthogonal polynomials. These theorems constitute an analytical solution to the Lanczos algorithm in that they are expressed in terms of the three-term recurrence coefficients α and β. These results can also be applied approximately for non-solvable models in the form of an expansion, in a descending series of the system size. The zeroth order order this expansion is just the manifestation of the central limit theorem in which a Gaussian measure and hermite polynomials arise. The first order represents the first non-trivial order, in which classical distribution functions like the binomial distributions arise and the associated class of orthogonal polynomials are Meixner polynomials. Amongst examples of systems which have infinite order in the expansion are q-orthogonal polynomials where q depends on the system size in a particular way. (author)
A summation procedure for expansions in orthogonal polynomials
International Nuclear Information System (INIS)
Garibotti, C.R.; Grinstein, F.F.
1977-01-01
Approximants to functions defined by formal series expansions in orthogonal polynomials are introduced. They are shown to be convergent even out of the elliptical domain where the original expansion converges
Skew-orthogonal polynomials and random matrix theory
Ghosh, Saugata
2009-01-01
Orthogonal polynomials satisfy a three-term recursion relation irrespective of the weight function with respect to which they are defined. This gives a simple formula for the kernel function, known in the literature as the Christoffel-Darboux sum. The availability of asymptotic results of orthogonal polynomials and the simple structure of the Christoffel-Darboux sum make the study of unitary ensembles of random matrices relatively straightforward. In this book, the author develops the theory of skew-orthogonal polynomials and obtains recursion relations which, unlike orthogonal polynomials, depend on weight functions. After deriving reduced expressions, called the generalized Christoffel-Darboux formulas (GCD), he obtains universal correlation functions and non-universal level densities for a wide class of random matrix ensembles using the GCD. The author also shows that once questions about higher order effects are considered (questions that are relevant in different branches of physics and mathematics) the ...
Benchmarking FeCr empirical potentials against density functional theory data
International Nuclear Information System (INIS)
Klaver, T P C; Bonny, G; Terentyev, D; Olsson, P
2010-01-01
Three semi-empirical force field FeCr potentials, two within the formalism of the two-band model and one within the formalism of the concentration dependent model, have been benchmarked against a wide variety of density functional theory (DFT) structures. The benchmarking allows an assessment of how reliable empirical potential results are in different areas relevant to radiation damage modelling. The DFT data consist of defect-free structures, structures with single interstitials and structures with small di- and tri-interstitial clusters. All three potentials reproduce the general trend of the heat of formation (h.o.f.) quite well. The most important shortcomings of the original two-band model potential are the low or even negative h.o.f. for Cr-rich structures and the lack of a strong repulsion when moving two solute Cr atoms from being second-nearest neighbours to nearest neighbours. The newer two-band model potential partly solves the first problem. The most important shortcoming in the concentration dependent model potential is the magnitude of the Cr–Cr repulsion, being too strong at short distances and mostly absent at longer distances. Both two-band model potentials do reproduce long-range Cr–Cr repulsion. For interstitials the two-band model potentials reproduce a number of Cr–interstitial binding energies surprisingly well, in contrast to the concentration dependent model potential. For Cr interacting with clusters, the result can sometimes be directly extrapolated from Cr interacting with single interstitials, both according to DFT and the three empirical potentials
Spencer, Amy V; Cox, Angela; Lin, Wei-Yu; Easton, Douglas F; Michailidou, Kyriaki; Walters, Kevin
2016-04-01
There is a large amount of functional genetic data available, which can be used to inform fine-mapping association studies (in diseases with well-characterised disease pathways). Single nucleotide polymorphism (SNP) prioritization via Bayes factors is attractive because prior information can inform the effect size or the prior probability of causal association. This approach requires the specification of the effect size. If the information needed to estimate a priori the probability density for the effect sizes for causal SNPs in a genomic region isn't consistent or isn't available, then specifying a prior variance for the effect sizes is challenging. We propose both an empirical method to estimate this prior variance, and a coherent approach to using SNP-level functional data, to inform the prior probability of causal association. Through simulation we show that when ranking SNPs by our empirical Bayes factor in a fine-mapping study, the causal SNP rank is generally as high or higher than the rank using Bayes factors with other plausible values of the prior variance. Importantly, we also show that assigning SNP-specific prior probabilities of association based on expert prior functional knowledge of the disease mechanism can lead to improved causal SNPs ranks compared to ranking with identical prior probabilities of association. We demonstrate the use of our methods by applying the methods to the fine mapping of the CASP8 region of chromosome 2 using genotype data from the Collaborative Oncological Gene-Environment Study (COGS) Consortium. The data we analysed included approximately 46,000 breast cancer case and 43,000 healthy control samples. © 2016 The Authors. *Genetic Epidemiology published by Wiley Periodicals, Inc.
Directory of Open Access Journals (Sweden)
Bogusław Michalec
2015-08-01
Full Text Available Understanding and defining the spatial distribution of sediment deposited in reservoirs is essential not only at the design stage but also during the operation. The majority of research concerns the distribution of sediment deposition in medium and large water reservoirs. Most empirical methods do not provide satisfactory results when applied to the determination of sediment deposition in small reservoirs. Small reservoir’s volumes do not exceed 5 × 106 m3 and their capacity-inflow ratio is less than 10%. Long-term silting measurements of three small reservoirs were used to evaluate the method described by Rahmanian and Banihashemi for predicting sediment distributions in small reservoirs. Rahmanian and Banihashemi stated that their model of distribution of sediment deposition in water reservoir works well for a long duration operation. In the presented study, the silting rate was used in order to determine the long duration operation. Silting rate is a quotient of volume of the sediment deposited in the reservoir and its original volume. It was stated that when the silting rate had reached 50%, the sediment deposition in the reservoir may be described by an empirical reservoir depth shape function (RDSF.
The Empirical Definition of the Function of Advertising Costs in E-Commerce
Directory of Open Access Journals (Sweden)
Pursky Oleg I.
2017-06-01
Full Text Available In the publication, an empirical study of the advertising costs in the e-commerce market is carried out. In order to determine the type of functional dependency of advertising costs, dynamics of advertising costs in the e-commerce markets of the US, the world, and Ukraine were researched, followed by an approximation of the series of statistical data on the Internet advertising costs. There is a functional dependency on the Internet advertising costs in the form of a power function with two coefficients that relate to the level of consumer awareness of goods and services in the e-commerce market and the level of saturation of the e-commerce market for advertising investments. The use of the power function of advertising costs has allowed to theoretical definition and statistical confirmation of existence of the effect of saturation of the developed e-commerce markets with advertising, where the growth of investment volumes in the Internet advertising begin with an increase, then peak and start to decline. The optimal level of advertising costs is determined by the condition of the full consumer awareness and the maximum saturation of the e-commerce market with advertising.
Orthogonal sparse linear discriminant analysis
Liu, Zhonghua; Liu, Gang; Pu, Jiexin; Wang, Xiaohong; Wang, Haijun
2018-03-01
Linear discriminant analysis (LDA) is a linear feature extraction approach, and it has received much attention. On the basis of LDA, researchers have done a lot of research work on it, and many variant versions of LDA were proposed. However, the inherent problem of LDA cannot be solved very well by the variant methods. The major disadvantages of the classical LDA are as follows. First, it is sensitive to outliers and noises. Second, only the global discriminant structure is preserved, while the local discriminant information is ignored. In this paper, we present a new orthogonal sparse linear discriminant analysis (OSLDA) algorithm. The k nearest neighbour graph is first constructed to preserve the locality discriminant information of sample points. Then, L2,1-norm constraint on the projection matrix is used to act as loss function, which can make the proposed method robust to outliers in data points. Extensive experiments have been performed on several standard public image databases, and the experiment results demonstrate the performance of the proposed OSLDA algorithm.
An Empirical Comparison of Seven Iterative and Evolutionary Function Optimization Heuristics
Baluja, Shumeet
1995-01-01
This report is a repository of the results obtained from a large scale empirical comparison of seven iterative and evolution-based optimization heuristics. Twenty-seven static optimization problems, spanning six sets of problem classes which are commonly explored in genetic algorithm literature, are examined. The problem sets include job-shop scheduling, traveling salesman, knapsack, binpacking, neural network weight optimization, and standard numerical optimization. The search spaces in these problems range from 2368 to 22040. The results indicate that using genetic algorithms for the optimization of static functions does not yield a benefit, in terms of the final answer obtained, over simpler optimization heuristics. Descriptions of the algorithms tested and the encodings of the problems are described in detail for reproducibility.
Skew-orthogonal polynomials, differential systems and random matrix theory
International Nuclear Information System (INIS)
Ghosh, S.
2007-01-01
We study skew-orthogonal polynomials with respect to the weight function exp[-2V (x)], with V (x) = Σ K=1 2d (u K /K)x K , u 2d > 0, d > 0. A finite subsequence of such skew-orthogonal polynomials arising in the study of Orthogonal and Symplectic ensembles of random matrices, satisfy a system of differential-difference-deformation equation. The vectors formed by such subsequence has the rank equal to the degree of the potential in the quaternion sense. These solutions satisfy certain compatibility condition and hence admit a simultaneous fundamental system of solutions. (author)
Iampietro, Mary; Giovannetti, Tania; Drabick, Deborah A. G.; Kessler, Rachel K.
2013-01-01
Executive function (EF) deficits in schizophrenia (SZ) are well documented, although much less is known about patterns of EF deficits and their association to differential impairments in everyday functioning. The present study empirically defined SZ groups based on measures of various EF abilities and then compared these EF groups on everyday action errors. Participants (n=45) completed various subtests from the Delis–Kaplan Executive Function System (D-KEFS) and the Naturalistic Action Test (NAT), a performance-based measure of everyday action that yields scores reflecting total errors and a range of different error types (e.g., omission, perseveration). Results of a latent class analysis revealed three distinct EF groups, characterized by (a) multiple EF deficits, (b) relatively spared EF, and (c) perseverative responding. Follow-up analyses revealed that the classes differed significantly on NAT total errors, total commission errors, and total perseveration errors; the two classes with EF impairment performed comparably on the NAT but performed worse than the class with relatively spared EF. In sum, people with SZ demonstrate variable patterns of EF deficits, and distinct aspects of these EF deficit patterns (i.e., poor mental control abilities) may be associated with everyday functioning capabilities. PMID:23035705
Empirical scoring functions for advanced protein-ligand docking with PLANTS.
Korb, Oliver; Stützle, Thomas; Exner, Thomas E
2009-01-01
In this paper we present two empirical scoring functions, PLANTS(CHEMPLP) and PLANTS(PLP), designed for our docking algorithm PLANTS (Protein-Ligand ANT System), which is based on ant colony optimization (ACO). They are related, regarding their functional form, to parts of already published scoring functions and force fields. The parametrization procedure described here was able to identify several parameter settings showing an excellent performance for the task of pose prediction on two test sets comprising 298 complexes in total. Up to 87% of the complexes of the Astex diverse set and 77% of the CCDC/Astex clean listnc (noncovalently bound complexes of the clean list) could be reproduced with root-mean-square deviations of less than 2 A with respect to the experimentally determined structures. A comparison with the state-of-the-art docking tool GOLD clearly shows that this is, especially for the druglike Astex diverse set, an improvement in pose prediction performance. Additionally, optimized parameter settings for the search algorithm were identified, which can be used to balance pose prediction reliability and search speed.
Source analysis using regional empirical Green's functions: The 2008 Wells, Nevada, earthquake
Mendoza, C.; Hartzell, S.
2009-01-01
We invert three-component, regional broadband waveforms recorded for the 21 February 2008 Wells, Nevada, earthquake using a finite-fault methodology that prescribes subfault responses using eight MW∼4 aftershocks as empirical Green's functions (EGFs) distributed within a 20-km by 21.6-km fault area. The inversion identifies a seismic moment of 6.2 x 1024 dyne-cm (5.8 MW) with slip concentrated in a compact 6.5-km by 4-km region updip from the hypocenter. The peak slip within this localized area is 88 cm and the stress drop is 72 bars, which is higher than expected for Basin and Range normal faults in the western United States. The EGF approach yields excellent fits to the complex regional waveforms, accounting for strong variations in wave propagation and site effects. This suggests that the procedure is useful for studying moderate-size earthquakes with limited teleseismic or strong-motion data and for examining uncertainties in slip models obtained using theoretical Green's functions.
Biogeography-Based Optimization with Orthogonal Crossover
Directory of Open Access Journals (Sweden)
Quanxi Feng
2013-01-01
Full Text Available Biogeography-based optimization (BBO is a new biogeography inspired, population-based algorithm, which mainly uses migration operator to share information among solutions. Similar to crossover operator in genetic algorithm, migration operator is a probabilistic operator and only generates the vertex of a hyperrectangle defined by the emigration and immigration vectors. Therefore, the exploration ability of BBO may be limited. Orthogonal crossover operator with quantization technique (QOX is based on orthogonal design and can generate representative solution in solution space. In this paper, a BBO variant is presented through embedding the QOX operator in BBO algorithm. Additionally, a modified migration equation is used to improve the population diversity. Several experiments are conducted on 23 benchmark functions. Experimental results show that the proposed algorithm is capable of locating the optimal or closed-to-optimal solution. Comparisons with other variants of BBO algorithms and state-of-the-art orthogonal-based evolutionary algorithms demonstrate that our proposed algorithm possesses faster global convergence rate, high-precision solution, and stronger robustness. Finally, the analysis result of the performance of QOX indicates that QOX plays a key role in the proposed algorithm.
Summers, Richard L; Pipke, Matt; Wegerich, Stephan; Conkright, Gary; Isom, Kristen C
2014-01-01
Background. Monitoring cardiovascular hemodynamics in the modern clinical setting is a major challenge. Increasing amounts of physiologic data must be analyzed and interpreted in the context of the individual patients pathology and inherent biologic variability. Certain data-driven analytical methods are currently being explored for smart monitoring of data streams from patients as a first tier automated detection system for clinical deterioration. As a prelude to human clinical trials, an empirical multivariate machine learning method called Similarity-Based Modeling (SBM), was tested in an In Silico experiment using data generated with the aid of a detailed computer simulator of human physiology (Quantitative Circulatory Physiology or QCP) which contains complex control systems with realistic integrated feedback loops. Methods. SBM is a kernel-based, multivariate machine learning method that that uses monitored clinical information to generate an empirical model of a patients physiologic state. This platform allows for the use of predictive analytic techniques to identify early changes in a patients condition that are indicative of a state of deterioration or instability. The integrity of the technique was tested through an In Silico experiment using QCP in which the output of computer simulations of a slowly evolving cardiac tamponade resulted in progressive state of cardiovascular decompensation. Simulator outputs for the variables under consideration were generated at a 2-min data rate (0.083Hz) with the tamponade introduced at a point 420 minutes into the simulation sequence. The functionality of the SBM predictive analytics methodology to identify clinical deterioration was compared to the thresholds used by conventional monitoring methods. Results. The SBM modeling method was found to closely track the normal physiologic variation as simulated by QCP. With the slow development of the tamponade, the SBM model are seen to disagree while the
Pernot, Pascal; Savin, Andreas
2018-06-01
Benchmarking studies in computational chemistry use reference datasets to assess the accuracy of a method through error statistics. The commonly used error statistics, such as the mean signed and mean unsigned errors, do not inform end-users on the expected amplitude of prediction errors attached to these methods. We show that, the distributions of model errors being neither normal nor zero-centered, these error statistics cannot be used to infer prediction error probabilities. To overcome this limitation, we advocate for the use of more informative statistics, based on the empirical cumulative distribution function of unsigned errors, namely, (1) the probability for a new calculation to have an absolute error below a chosen threshold and (2) the maximal amplitude of errors one can expect with a chosen high confidence level. Those statistics are also shown to be well suited for benchmarking and ranking studies. Moreover, the standard error on all benchmarking statistics depends on the size of the reference dataset. Systematic publication of these standard errors would be very helpful to assess the statistical reliability of benchmarking conclusions.
New discrete orthogonal moments for signal analysis
Czech Academy of Sciences Publication Activity Database
Honarvar Shakibaei Asli, Barmak; Flusser, Jan
2017-01-01
Roč. 141, č. 1 (2017), s. 57-73 ISSN 0165-1684 R&D Projects: GA ČR GA15-16928S Institutional support: RVO:67985556 Keywords : Orthogonal polynomials * Moment functions * Z-transform * Rodrigues formula * Hypergeometric form Subject RIV: JD - Computer Applications, Robotics OBOR OECD: Computer sciences, information science, bioinformathics (hardware development to be 2.2, social aspect to be 5.8) Impact factor: 3.110, year: 2016 http://library.utia.cas.cz/separaty/2017/ZOI/flusser-0475248.pdf
Chen, Dongyue; Lin, Jianhui; Li, Yanping
2018-06-01
Complementary ensemble empirical mode decomposition (CEEMD) has been developed for the mode-mixing problem in Empirical Mode Decomposition (EMD) method. Compared to the ensemble empirical mode decomposition (EEMD), the CEEMD method reduces residue noise in the signal reconstruction. Both CEEMD and EEMD need enough ensemble number to reduce the residue noise, and hence it would be too much computation cost. Moreover, the selection of intrinsic mode functions (IMFs) for further analysis usually depends on experience. A modified CEEMD method and IMFs evaluation index are proposed with the aim of reducing the computational cost and select IMFs automatically. A simulated signal and in-service high-speed train gearbox vibration signals are employed to validate the proposed method in this paper. The results demonstrate that the modified CEEMD can decompose the signal efficiently with less computation cost, and the IMFs evaluation index can select the meaningful IMFs automatically.
Energy Technology Data Exchange (ETDEWEB)
Elskens, Marc [Vrije Universiteit Brussel, Analytical, Pleinlaan 2, BE-1050 Brussels (Belgium); Gourgue, Olivier [Université catholique de Louvain, Institute of Mechanics, Materials and Civil Engineering (IMMC), 4 Avenue G. Lemaître, bte L4.05.02, BE-1348 Louvain-la-Neuve (Belgium); Université catholique de Louvain, Georges Lemaître Centre for Earth and Climate Research (TECLIM), Place Louis Pasteur 2, bte L4.03.08, BE-1348 Louvain-la-Neuve (Belgium); Baeyens, Willy [Vrije Universiteit Brussel, Analytical, Pleinlaan 2, BE-1050 Brussels (Belgium); Chou, Lei [Université Libre de Bruxelles, Biogéochimie et Modélisation du Système Terre (BGéoSys) —Océanographie Chimique et Géochimie des Eaux, Campus de la Plaine —CP 208, Boulevard du Triomphe, BE-1050 Brussels (Belgium); Deleersnijder, Eric [Université catholique de Louvain, Institute of Mechanics, Materials and Civil Engineering (IMMC), 4 Avenue G. Lemaître, bte L4.05.02, BE-1348 Louvain-la-Neuve (Belgium); Université catholique de Louvain, Earth and Life Institute (ELI), Georges Lemaître Centre for Earth and Climate Research (TECLIM), Place Louis Pasteur 2, bte L4.03.08, BE-1348 Louvain-la-Neuve (Belgium); Leermakers, Martine [Vrije Universiteit Brussel, Analytical, Pleinlaan 2, BE-1050 Brussels (Belgium); and others
2014-04-01
Predicting metal concentrations in surface waters is an important step in the understanding and ultimately the assessment of the ecological risk associated with metal contamination. In terms of risk an essential piece of information is the accurate knowledge of the partitioning of the metals between the dissolved and particulate phases, as the former species are generally regarded as the most bioavailable and thus harmful form. As a first step towards the understanding and prediction of metal speciation in the Scheldt Estuary (Belgium, the Netherlands), we carried out a detailed analysis of a historical dataset covering the period 1982–2011. This study reports on the results for two selected metals: Cu and Cd. Data analysis revealed that both the total metal concentration and the metal partitioning coefficient (K{sub d}) could be predicted using relatively simple empirical functions of environmental variables such as salinity and suspended particulate matter concentration (SPM). The validity of these functions has been assessed by their application to salinity and SPM fields simulated by the hydro-environmental model SLIM. The high-resolution total and dissolved metal concentrations reconstructed using this approach, compared surprisingly well with an independent set of validation measurements. These first results from the combined mechanistic-empirical model approach suggest that it may be an interesting tool for risk assessment studies, e.g. to help identify conditions associated with elevated (dissolved) metal concentrations. - Highlights: • Empirical functions were designed for assessing metal speciation in estuarine water. • The empirical functions were implemented in the hydro-environmental model SLIM. • Validation was carried out in the Scheldt Estuary using historical data 1982–2011. • This combined mechanistic-empirical approach is useful for risk assessment.
Orthogonality preserving infinite dimensional quadratic stochastic operators
International Nuclear Information System (INIS)
Akın, Hasan; Mukhamedov, Farrukh
2015-01-01
In the present paper, we consider a notion of orthogonal preserving nonlinear operators. We introduce π-Volterra quadratic operators finite and infinite dimensional settings. It is proved that any orthogonal preserving quadratic operator on finite dimensional simplex is π-Volterra quadratic operator. In infinite dimensional setting, we describe all π-Volterra operators in terms orthogonal preserving operators
Polar plate theory for orthogonal anisotropy
Bailey, Michelle D.
1998-11-01
The following paper discusses the derivation and evaluation of the plate equations for a circular composite disk with orthogonal anisotropy. The work will be on a macromechanical level and include buckling, static and dynamic load applications. Necessary to a complete examination of the circular disk is the conversion of the stiffness matrix to cylindrical coordinates. In the transformed state, these coefficients are no longer constant, adding to the complexity of the proposed differential equations. Laminated fiber-reinforced (or filamentary) composites are used today for their high strength-to weight and stiffness-to-weight ratios. However, because of the typical anisotropic behavior of composites, determining the material properties on a microscopic level and the mechanics on a macroscopic level is much more difficult. This difficulty manifests itself particularly well in the evaluation of material properties and governing differential equations of a circular disk with the fibers of the lamina oriented orthogonally. One could encounter such a situation in space structures that require a circular geometry. For example, determining fastener pull through in a circular composite plate would best be performed in a polar coordinate system. In order to calculate the strain (which is a function of the angle, θ) from the displacements, the stiffness matrix and boundary conditions would need to be expressed in cylindrical coordinates. Naturally the composite would be constructed with fibers in orthogonal directions, then the necessary geometry would be cut out, thus the required lengthy transformation of coordinate systems. To bypass this derivation, numerical methods have been used and finite element models have been attempted. FEM over predicts plate stiffness by 20% and underpredicts failure by 70%. Obviously there is a need to transform classical plate theory to a cylindrical coordinate system.
Kernel versions of some orthogonal transformations
DEFF Research Database (Denmark)
Nielsen, Allan Aasbjerg
Kernel versions of orthogonal transformations such as principal components are based on a dual formulation also termed Q-mode analysis in which the data enter into the analysis via inner products in the Gram matrix only. In the kernel version the inner products of the original data are replaced...... by inner products between nonlinear mappings into higher dimensional feature space. Via kernel substitution also known as the kernel trick these inner products between the mappings are in turn replaced by a kernel function and all quantities needed in the analysis are expressed in terms of this kernel...... function. This means that we need not know the nonlinear mappings explicitly. Kernel principal component analysis (PCA) and kernel minimum noise fraction (MNF) analyses handle nonlinearities by implicitly transforming data into high (even infinite) dimensional feature space via the kernel function...
Ogle, K.; Fell, M.; Barber, J. J.
2016-12-01
Empirical, field studies of plant functional traits have revealed important trade-offs among pairs or triplets of traits, such as the leaf (LES) and wood (WES) economics spectra. Trade-offs include correlations between leaf longevity (LL) vs specific leaf area (SLA), LL vs mass-specific leaf respiration rate (RmL), SLA vs RmL, and resistance to breakage vs wood density. Ordination analyses (e.g., PCA) show groupings of traits that tend to align with different life-history strategies or taxonomic groups. It is unclear, however, what underlies such trade-offs and emergent spectra. Do they arise from inherent physiological constraints on growth, or are they more reflective of environmental filtering? The relative importance of these mechanisms has implications for predicting biogeochemical cycling, which is influenced by trait distributions of the plant community. We address this question using an individual-based model of tree growth (ACGCA) to quantify the theoretical trait space of trees that emerges from physiological constraints. ACGCA's inputs include 32 physiological, anatomical, and allometric traits, many of which are related to the LES and WES. We fit ACGCA to 1.6 million USFS FIA observations of tree diameters and heights to obtain vectors of trait values that produce realistic growth, and we explored the structure of this trait space. No notable correlations emerged among the 496 trait pairs, but stepwise regressions revealed complicated multi-variate structure: e.g., relationships between pairs of traits (e.g., RmL and SLA) are governed by other traits (e.g., LL, radiation-use efficiency [RUE]). We also simulated growth under various canopy gap scenarios that impose varying degrees of environmental filtering to explore the multi-dimensional trait space (hypervolume) of trees that died vs survived. The centroid and volume of the hypervolumes differed among dead and live trees, especially under gap conditions leading to low mortality. Traits most predictive
Jos, Sujit; Kumar, Preetam; Chakrabarti, Saswat
Orthogonal and quasi-orthogonal codes are integral part of any DS-CDMA based cellular systems. Orthogonal codes are ideal for use in perfectly synchronous scenario like downlink cellular communication. Quasi-orthogonal codes are preferred over orthogonal codes in the uplink communication where perfect synchronization cannot be achieved. In this paper, we attempt to compare orthogonal and quasi-orthogonal codes in presence of timing synchronization error. This will give insight into the synchronization demands in DS-CDMA systems employing the two classes of sequences. The synchronization error considered is smaller than chip duration. Monte-Carlo simulations have been carried out to verify the analytical and numerical results.
Orthogonal Expansions for VIX Options Under Affine Jump Diffusions
DEFF Research Database (Denmark)
Barletta, Andrea; Nicolato, Elisa
2017-01-01
In this work we derive new closed–form pricing formulas for VIX options in the jump-diffusion SVJJ model proposed by Duffie et al. (2000). Our approach is based on the classic methodology of approximating a density function with an orthogonal expansion of polynomials weighted by a kernel. Orthogo......In this work we derive new closed–form pricing formulas for VIX options in the jump-diffusion SVJJ model proposed by Duffie et al. (2000). Our approach is based on the classic methodology of approximating a density function with an orthogonal expansion of polynomials weighted by a kernel...
A note on the zeros of Freud-Sobolev orthogonal polynomials
Moreno-Balcazar, Juan J.
2007-10-01
We prove that the zeros of a certain family of Sobolev orthogonal polynomials involving the Freud weight function e-x4 on are real, simple, and interlace with the zeros of the Freud polynomials, i.e., those polynomials orthogonal with respect to the weight function e-x4. Some numerical examples are shown.
Orthogonal polynomials derived from the tridiagonal representation approach
Alhaidari, A. D.
2018-01-01
The tridiagonal representation approach is an algebraic method for solving second order differential wave equations. Using this approach in the solution of quantum mechanical problems, we encounter two new classes of orthogonal polynomials whose properties give the structure and dynamics of the corresponding physical system. For a certain range of parameters, one of these polynomials has a mix of continuous and discrete spectra making it suitable for describing physical systems with both scattering and bound states. In this work, we define these polynomials by their recursion relations and highlight some of their properties using numerical means. Due to the prime significance of these polynomials in physics, we hope that our short expose will encourage experts in the field of orthogonal polynomials to study them and derive their properties (weight functions, generating functions, asymptotics, orthogonality relations, zeros, etc.) analytically.
International Nuclear Information System (INIS)
Tel, E.; Aydin, E. G.; Aydin, A.; Kaplan, A.
2007-01-01
The hybrid reactor is a combination of the fusion and fission processes. In the fusion-fission hybrid reactor, tritium self-sufficiency must be maintained for a commercial power plant. For self-sustaining (D-T) fusion driver tritium breeding ratio should be greater than 1.05. Working out the systematics of (n,t) reaction cross sections is of great importance for the definition of the excitation function character for the given reaction taking place on various nuclei at energies up to 20 MeV. In this study, we have investigated the asymmetry term effect for the (n,t) reaction cross sections at 14-15 neutron incident energy. It has been discussed the odd even effect and the pairing effect considering binding energy systematic of the nuclear shell model for the new experimental data and new cross section formulas (n,t) reactions developed by Tel et al. We have determined a different parameter groups by the classification of nuclei into even-even, even-odd and odd-even for (n,t) reactions cross sections. The obtained empirical formulas by fitting two parameter for (n,t) reactions were given. All calculated results have been compared with the experimental data. By using the new cross sections formulas (n,t) reactions the obtained results have been discussed and compared with the available experimental data
Orthogonal polynomials and random matrices
Deift, Percy
2000-01-01
This volume expands on a set of lectures held at the Courant Institute on Riemann-Hilbert problems, orthogonal polynomials, and random matrix theory. The goal of the course was to prove universality for a variety of statistical quantities arising in the theory of random matrix models. The central question was the following: Why do very general ensembles of random n {\\times} n matrices exhibit universal behavior as n {\\rightarrow} {\\infty}? The main ingredient in the proof is the steepest descent method for oscillatory Riemann-Hilbert problems.
Owen, Art B
2001-01-01
Empirical likelihood provides inferences whose validity does not depend on specifying a parametric model for the data. Because it uses a likelihood, the method has certain inherent advantages over resampling methods: it uses the data to determine the shape of the confidence regions, and it makes it easy to combined data from multiple sources. It also facilitates incorporating side information, and it simplifies accounting for censored, truncated, or biased sampling.One of the first books published on the subject, Empirical Likelihood offers an in-depth treatment of this method for constructing confidence regions and testing hypotheses. The author applies empirical likelihood to a range of problems, from those as simple as setting a confidence region for a univariate mean under IID sampling, to problems defined through smooth functions of means, regression models, generalized linear models, estimating equations, or kernel smooths, and to sampling with non-identically distributed data. Abundant figures offer vi...
Quantitative Boltzmann-Gibbs Principles via Orthogonal Polynomial Duality
Ayala, Mario; Carinci, Gioia; Redig, Frank
2018-06-01
We study fluctuation fields of orthogonal polynomials in the context of particle systems with duality. We thereby obtain a systematic orthogonal decomposition of the fluctuation fields of local functions, where the order of every term can be quantified. This implies a quantitative generalization of the Boltzmann-Gibbs principle. In the context of independent random walkers, we complete this program, including also fluctuation fields in non-stationary context (local equilibrium). For other interacting particle systems with duality such as the symmetric exclusion process, similar results can be obtained, under precise conditions on the n particle dynamics.
Problems of the orthogonalized plane wave method. 1
International Nuclear Information System (INIS)
Farberovich, O.V.; Kurganskii, S.I.; Domashevskaya, E.P.
1979-01-01
The main problems of the orthogonalized plane wave method are discussed including (a) consideration of core states; (b) effect of overlap of wave functions of external core states upon the band structure; (c) calculation of d-type states. The modified orthogonal plane wave method (MOPW method) of Deegan and Twose is applied in a general form to solve the problems of the usual OPW method. For the first time the influence on the spectrum of the main parameters of the MOPW method is studied systematically by calculating the electronic energy spectrum in the transition metals Nb and V. (author)
Multiscale empirical interpolation for solving nonlinear PDEs
Calo, Victor M.
2014-12-01
In this paper, we propose a multiscale empirical interpolation method for solving nonlinear multiscale partial differential equations. The proposed method combines empirical interpolation techniques and local multiscale methods, such as the Generalized Multiscale Finite Element Method (GMsFEM). To solve nonlinear equations, the GMsFEM is used to represent the solution on a coarse grid with multiscale basis functions computed offline. Computing the GMsFEM solution involves calculating the system residuals and Jacobians on the fine grid. We use empirical interpolation concepts to evaluate these residuals and Jacobians of the multiscale system with a computational cost which is proportional to the size of the coarse-scale problem rather than the fully-resolved fine scale one. The empirical interpolation method uses basis functions which are built by sampling the nonlinear function we want to approximate a limited number of times. The coefficients needed for this approximation are computed in the offline stage by inverting an inexpensive linear system. The proposed multiscale empirical interpolation techniques: (1) divide computing the nonlinear function into coarse regions; (2) evaluate contributions of nonlinear functions in each coarse region taking advantage of a reduced-order representation of the solution; and (3) introduce multiscale proper-orthogonal-decomposition techniques to find appropriate interpolation vectors. We demonstrate the effectiveness of the proposed methods on several nonlinear multiscale PDEs that are solved with Newton\\'s methods and fully-implicit time marching schemes. Our numerical results show that the proposed methods provide a robust framework for solving nonlinear multiscale PDEs on a coarse grid with bounded error and significant computational cost reduction.
Synthesis of an Orthogonal Topological Analogue of Helicene
DEFF Research Database (Denmark)
Wixe, Torbjörn; Wallentin, Carl‐Johan; Johnson, Magnus T.
2013-01-01
The synthesis of an orthogonal topological pentamer analogue of helicene is presented. This analogue forms a tubular structure with its aromatic systems directed parallel to the axis of propagation, which creates a cavity with the potential to function as a host molecule. The synthetic strategy r...
On the non-orthogonal sampling scheme for Gabor's signal expansion
Bastiaans, M.J.; Leest, van A.J.; Veen, J.P.
2000-01-01
Gabor's signal expansion and the Gabor transform are formulated on a non-orthogonal time-frequency lattice instead of on the traditional rectangular lattice [1,2]. The reason for doing so is that a non-orthogonal sampling geometry might be better adapted to the form of the window functions (in the
Using Empirical Data to Estimate Potential Functions in Commodity Markets: Some Initial Results
Shen, C.; Haven, E.
2017-12-01
This paper focuses on estimating real and quantum potentials from financial commodities. The log returns of six common commodities are considered. We find that some phenomena, such as the vertical potential walls and the time scale issue of the variation on returns, also exists in commodity markets. By comparing the quantum and classical potentials, we attempt to demonstrate that the information within these two types of potentials is different. We believe this empirical result is consistent with the theoretical assumption that quantum potentials (when embedded into social science contexts) may contain some social cognitive or market psychological information, while classical potentials mainly reflect `hard' market conditions. We also compare the two potential forces and explore their relationship by simply estimating the Pearson correlation between them. The Medium or weak interaction effect may indicate that the cognitive system among traders may be affected by those `hard' market conditions.
Energy Technology Data Exchange (ETDEWEB)
Oie, Tetsuro [Univ. of Rochester, NY (United States); Univ. of Kansas, Lawrence, KS (United States). Dept. of Chemistry
1980-07-28
A purpose of the present studies is twofold: (1) development of an empirical potential function (EPF) and (2) application of it to the studies of photoreaction center chlorophyll a dimer. The reliable estimate of geometric structures and energies of large molecules by quantum mechanical methods is not possible at the present time. An alternative method is, therefore, needed for the studies of large molecular systems, and Chapter I is dedicated to the development of this tool, i.e., an empirical potential function, which could suffice this purpose. Because of a large number of variable chemical compositions and functional groups characteristically present in a large molecule, it is important to include a large number of structurally diverse molecules in the development of the EPF. In Chapter II, the EPF is applied to study the geometrical structure of a chlorophyll a (Chl a) dimer, which is believed to exist at the photoreaction center of green plants and is known to play an essential role in photosynthetic energy conversion. Although various models have been proposed for this dimer structure, there is still a great need for information concerning the detailed geometric structure of this dimer. Therefore, in this chapter the structural stabilities of various dimer models are examined by the EPF, and detailed and quantitative information on the structure and stability of these models is provided.
Directory of Open Access Journals (Sweden)
Wałęga Andrzej
2017-12-01
Full Text Available The aim of the study was to assess the applicability of asymptotic functions for determining the value of CN parameter as a function of precipitation depth in mountain and upland catchments. The analyses were carried out in two catchments: the Rudawa, left tributary of the Vistula, and the Kamienica, right tributary of the Dunajec. The input material included data on precipitation and flows for a multi-year period 1980–2012, obtained from IMGW PIB in Warsaw. Two models were used to determine empirical values of CNobs parameter as a function of precipitation depth: standard Hawkins model and 2-CN model allowing for a heterogeneous nature of a catchment area.
Wong, Z C; Fan, W Y; Chwee, T S; Sullivan, Michael B
2017-08-09
Fluorescence lifetimes were evaluated using TD-DFT under different approximations for the emitting molecule and various exchange-correlation functionals, such as B3LYP, BMK, CAM-B3LYP, LC-BLYP, M06, M06-2X, M11, PBE0, ωB97, ωB97X, LC-BLYP*, and ωB97X* where the range-separation parameters in the last two functionals were tuned in a non-empirical fashion. Changes in the optimised molecular geometries between the ground and electronically excited states were found to affect the quality of the calculated lifetimes significantly, while the inclusion of vibronic features led to further improvements over the assumption of a vertical electronic transition. The LC-BLYP* functional was found to return the most accurate fluorescence lifetimes with unsigned errors that are mostly within 1.5 ns of experimental values.
Crossover ensembles of random matrices and skew-orthogonal polynomials
International Nuclear Information System (INIS)
Kumar, Santosh; Pandey, Akhilesh
2011-01-01
Highlights: → We study crossover ensembles of Jacobi family of random matrices. → We consider correlations for orthogonal-unitary and symplectic-unitary crossovers. → We use the method of skew-orthogonal polynomials and quaternion determinants. → We prove universality of spectral correlations in crossover ensembles. → We discuss applications to quantum conductance and communication theory problems. - Abstract: In a recent paper (S. Kumar, A. Pandey, Phys. Rev. E, 79, 2009, p. 026211) we considered Jacobi family (including Laguerre and Gaussian cases) of random matrix ensembles and reported exact solutions of crossover problems involving time-reversal symmetry breaking. In the present paper we give details of the work. We start with Dyson's Brownian motion description of random matrix ensembles and obtain universal hierarchic relations among the unfolded correlation functions. For arbitrary dimensions we derive the joint probability density (jpd) of eigenvalues for all transitions leading to unitary ensembles as equilibrium ensembles. We focus on the orthogonal-unitary and symplectic-unitary crossovers and give generic expressions for jpd of eigenvalues, two-point kernels and n-level correlation functions. This involves generalization of the theory of skew-orthogonal polynomials to crossover ensembles. We also consider crossovers in the circular ensembles to show the generality of our method. In the large dimensionality limit, correlations in spectra with arbitrary initial density are shown to be universal when expressed in terms of a rescaled symmetry breaking parameter. Applications of our crossover results to communication theory and quantum conductance problems are also briefly discussed.
On Orthogonal Decomposition of a Sobolev Space
Lakew, Dejenie A.
2016-01-01
The theme of this short article is to investigate an orthogonal decomposition of a Sobolev space and look at some properties of the inner product therein and the distance defined from the inner product. We also determine the dimension of the orthogonal difference space and show the expansion of spaces as their regularity increases.
Benefits of Applying Hierarchical Models to the Empirical Green's Function Approach
Denolle, M.; Van Houtte, C.
2017-12-01
Stress drops calculated from source spectral studies currently show larger variability than what is implied by empirical ground motion models. One of the potential origins of the inflated variability is the simplified model-fitting techniques used in most source spectral studies. This study improves upon these existing methods, and shows that the fitting method may explain some of the discrepancy. In particular, Bayesian hierarchical modelling is shown to be a method that can reduce bias, better quantify uncertainties and allow additional effects to be resolved. The method is applied to the Mw7.1 Kumamoto, Japan earthquake, and other global, moderate-magnitude, strike-slip earthquakes between Mw5 and Mw7.5. It is shown that the variation of the corner frequency, fc, and the falloff rate, n, across the focal sphere can be reliably retrieved without overfitting the data. Additionally, it is shown that methods commonly used to calculate corner frequencies can give substantial biases. In particular, if fc were calculated for the Kumamoto earthquake using a model with a falloff rate fixed at 2 instead of the best fit 1.6, the obtained fc would be as large as twice its realistic value. The reliable retrieval of the falloff rate allows deeper examination of this parameter for a suite of global, strike-slip earthquakes, and its scaling with magnitude. The earthquake sequences considered in this study are from Japan, New Zealand, Haiti and California.
Benzina, Amal; Dey, Arindam; Toennis, Marcus; Klinker, Gudrun
2012-01-01
interaction technique (separability). This paper examines, how many DOF are needed to perform the travel task as easy and comfortable as possible. It also investigates different mapping functions between the user's actions on the mobile phone and the viewpoint
Aydemir, Ömer; Çubukçuoğlu, Zeynep; Erdin, Soner; Taş, Cumhur; Onur, Ece; Berk, Michael
2014-01-01
This study aimed to evaluate the relationship between oxidative stress markers and cognitive functions and domains of psychosocial functioning in bipolar disorder. Oxidative stress markers, cognitive functions, and domains of psychosocial functioning were evaluated in 51 patients with bipolar disorder who were in remission. Correlation analyses between these parameters were calculated with data controlled for duration of illness and number of episodes. There was no statistically significant correlation between oxidative stress markers and cognitive functions. In terms of psychosocial functioning, significant correlations were found between malondialdehyde and sense of stigmatization (r = -0.502); household activities and superoxide dismutase (r = 0.501); participation in social activities and nitric oxide (r = 0.414); hobbies and leisure time activities and total glutathione (r = -0.567), superoxide dismutase (r = 0.667), and neurotrophin 4 (r = 0.450); and taking initiative and self-sufficiency and superoxide dismutase (r = 0.597). There was no correlation between other domains of psychosocial functioning and oxidative stress markers. These results imply that oxidative stress markers do not appear to correlate clearly with cognitive impairment and reduced psychosocial functioning. However, there were some associations between selected oxidative markers and activity-oriented functional markers. This may represent a true negative association, or may be an artifact of oxidative stress being a state rather than a trait marker.
Directory of Open Access Journals (Sweden)
Ömer Aydemir
2014-12-01
Full Text Available Objective: This study aimed to evaluate the relationship between oxidative stress markers and cognitive functions and domains of psychosocial functioning in bipolar disorder. Methods: Oxidative stress markers, cognitive functions, and domains of psychosocial functioning were evaluated in 51 patients with bipolar disorder who were in remission. Correlation analyses between these parameters were calculated with data controlled for duration of illness and number of episodes. Results: There was no statistically significant correlation between oxidative stress markers and cognitive functions. In terms of psychosocial functioning, significant correlations were found between malondialdehyde and sense of stigmatization (r = -0.502; household activities and superoxide dismutase (r = 0.501; participation in social activities and nitric oxide (r = 0.414; hobbies and leisure time activities and total glutathione (r = -0.567, superoxide dismutase (r = 0.667, and neurotrophin 4 (r = 0.450; and taking initiative and self-sufficiency and superoxide dismutase (r = 0.597. There was no correlation between other domains of psychosocial functioning and oxidative stress markers. Conclusion: These results imply that oxidative stress markers do not appear to correlate clearly with cognitive impairment and reduced psychosocial functioning. However, there were some associations between selected oxidative markers and activity-oriented functional markers. This may represent a true negative association, or may be an artifact of oxidative stress being a state rather than a trait marker.
An Empirical Analysis of the Price Discovery Function of Shanghai Fuel Oil Futures Market
Institute of Scientific and Technical Information of China (English)
Wang Zhen; Liu Zhenhai; Chen Chao
2007-01-01
This paper analyzes the role of price discovery of Shanghai fuel oil futures market by using methods, such as unit root test, co-integration test, error correction model, Granger causality test, impulse-response function and variance decomposition. The results showed that there exists a strong relationship between the spot price of Huangpu fuel oil spot market and the futures price of Shanghai fuel oil futures market. In addition, the Shanghai fuel oil futures market exhibits a highly effective price discovery function.
International Nuclear Information System (INIS)
Varma, M.N.; Bond, V.P.
1982-01-01
Microdosimetric spectra for 0.43, 1.8, and 14.7 MeV neutrons, and for 215 kVp x rays and 1250 keV gammas were used in conjunction with relative biological effectiveness (RBE) values for pink mutations in Tradescantia to obtain an effectiveness function (i.e., a cell critical volume dose vs. cell response function). This effectiveness function (or hit size weighting function) provides the probability of inducing a biological effect of interest (in the present study, pink mutations in Tradescantia) as a function of lineal energy density y. In a preliminary analysis the critical value of y above which pink mutations are seen was 4.5 keV/μm, and the value of y at which the probability reaches unity was 115 keV/μm. Idealized but approximate event size distributions for mono-LET particles ranging from 10 to 5000 keV/μm were generated, and these distributions were weighted by the effectiveness function to determine the pink mutation frequencies. Results are compared with measured pink mutation frequencies for 11 keV/μm ( 12 C) and 31 keV/μm ( 20 Ne) ions
Tadesse Woeldesenbet, T.
2012-01-01
Rural areas in many developing countries often lack infrastructure and institutions. However, rural towns and towns possess some of the major services that rural and town households can use to advance their economic activities. The study of the contribution that towns and their functions make to
Implied adjusted volatility functions: Empirical evidence from Australian index option market
Harun, Hanani Farhah; Hafizah, Mimi
2015-02-01
This study aims to investigate the implied adjusted volatility functions using the different Leland option pricing models and to assess whether the use of the specified implied adjusted volatility function can lead to an improvement in option valuation accuracy. The implied adjusted volatility is investigated in the context of Standard and Poor/Australian Stock Exchange (S&P/ASX) 200 index options over the course of 2001-2010, which covers the global financial crisis in the mid-2007 until the end of 2008. Both in- and out-of-sample resulted in approximately similar pricing error along the different Leland models. Results indicate that symmetric and asymmetric models of both moneyness ratio and logarithmic transformation of moneyness provide the overall best result in both during and post-crisis periods. We find that in the different period of interval (pre-, during and post-crisis) is subject to a different implied adjusted volatility function which best explains the index options. Hence, it is tremendously important to identify the intervals beforehand in investigating the implied adjusted volatility function.
The Functional Independence of Mands and Tacts: Has It Been Demonstrated Empirically?
Gamba, Jonas; Goyos, Celso; Petursdottir, Anna Ingeborg
2015-01-01
Recently, there has been a proliferation of research on the functional independence of two of Skinner's (1957) verbal operants, the mand, and the tact. This research has produced highly variable results. In this article, we provide a critical review of the literature on mand-tact independence, a literature that has implications for both theory and…
[Orthogonal Vector Projection Algorithm for Spectral Unmixing].
Song, Mei-ping; Xu, Xing-wei; Chang, Chein-I; An, Ju-bai; Yao, Li
2015-12-01
Spectrum unmixing is an important part of hyperspectral technologies, which is essential for material quantity analysis in hyperspectral imagery. Most linear unmixing algorithms require computations of matrix multiplication and matrix inversion or matrix determination. These are difficult for programming, especially hard for realization on hardware. At the same time, the computation costs of the algorithms increase significantly as the number of endmembers grows. Here, based on the traditional algorithm Orthogonal Subspace Projection, a new method called. Orthogonal Vector Projection is prompted using orthogonal principle. It simplifies this process by avoiding matrix multiplication and inversion. It firstly computes the final orthogonal vector via Gram-Schmidt process for each endmember spectrum. And then, these orthogonal vectors are used as projection vector for the pixel signature. The unconstrained abundance can be obtained directly by projecting the signature to the projection vectors, and computing the ratio of projected vector length and orthogonal vector length. Compared to the Orthogonal Subspace Projection and Least Squares Error algorithms, this method does not need matrix inversion, which is much computation costing and hard to implement on hardware. It just completes the orthogonalization process by repeated vector operations, easy for application on both parallel computation and hardware. The reasonability of the algorithm is proved by its relationship with Orthogonal Sub-space Projection and Least Squares Error algorithms. And its computational complexity is also compared with the other two algorithms', which is the lowest one. At last, the experimental results on synthetic image and real image are also provided, giving another evidence for effectiveness of the method.
On orthogonality preserving quadratic stochastic operators
Energy Technology Data Exchange (ETDEWEB)
Mukhamedov, Farrukh; Taha, Muhammad Hafizuddin Mohd [Department of Computational and Theoretical Sciences, Faculty of Science International Islamic University Malaysia, P.O. Box 141, 25710 Kuantan, Pahang Malaysia (Malaysia)
2015-05-15
A quadratic stochastic operator (in short QSO) is usually used to present the time evolution of differing species in biology. Some quadratic stochastic operators have been studied by Lotka and Volterra. In the present paper, we first give a simple characterization of Volterra QSO in terms of absolutely continuity of discrete measures. Further, we introduce a notion of orthogonal preserving QSO, and describe such kind of operators defined on two dimensional simplex. It turns out that orthogonal preserving QSOs are permutations of Volterra QSO. The associativity of genetic algebras generated by orthogonal preserving QSO is studied too.
On orthogonality preserving quadratic stochastic operators
International Nuclear Information System (INIS)
Mukhamedov, Farrukh; Taha, Muhammad Hafizuddin Mohd
2015-01-01
A quadratic stochastic operator (in short QSO) is usually used to present the time evolution of differing species in biology. Some quadratic stochastic operators have been studied by Lotka and Volterra. In the present paper, we first give a simple characterization of Volterra QSO in terms of absolutely continuity of discrete measures. Further, we introduce a notion of orthogonal preserving QSO, and describe such kind of operators defined on two dimensional simplex. It turns out that orthogonal preserving QSOs are permutations of Volterra QSO. The associativity of genetic algebras generated by orthogonal preserving QSO is studied too
Structural evolution of amino acid crystals under stress from a non-empirical density functional
International Nuclear Information System (INIS)
Sabatini, Riccardo; Küçükbenli, Emine; De Gironcoli, Stefano; Kolb, Brian; Thonhauser, T
2012-01-01
Use of the non-local correlation functional vdW-DF (from ‘van der Waals density functional’; Dion M et al 2004 Phys. Rev. Lett. 92 246401) has become a popular approach for including van der Waals interactions within density functional theory. In this work, we extend the vdW-DF theory and derive the corresponding stress tensor in a fashion similar to the LDA and GGA approach, which allows for a straightforward implementation in any electronic structure code. We then apply our methodology to investigate the structural evolution of amino acid crystals of glycine and l-alanine under pressure up to 10 GPa - with and without van der Waals interactions - and find that for an accurate description of intermolecular interactions and phase transitions in these systems, the inclusion of van der Waals interactions is crucial. For glycine, calculations including the vdW-DF (vdW-DF-c09x) functional are found to systematically overestimate (underestimate) the crystal lattice parameters, yet the stability ordering of the different polymorphs is determined accurately, at variance with the GGA case. In the case of l-alanine, our vdW-DF results agree with recent experiments that question the phase transition reported for this crystal at 2.3 GPa, as the a and c cell parameters happen to become equal but no phase transition is observed.
Intrinsic Regularization in a Lorentz invariant non-orthogonal Euclidean Space
Tornow, Carmen
2006-01-01
It is shown that the Lorentz transformations can be derived for a non-orthogonal Euclidean space. In this geometry one finds the same relations of special relativity as the ones known from the orthogonal Minkowski space. In order to illustrate the advantage of a non-orthogonal Euclidean metric the two-point Green’s function at x = 0 for a self-interacting scalar field is calculated. In contrast to the Minkowski space the one loop mass correction derived from this function gives a convergent r...
Bouy, H.; Bertin, E.; Sarro, L. M.; Barrado, D.; Moraux, E.; Bouvier, J.; Cuillandre, J.-C.; Berihuete, A.; Olivares, J.; Beletsky, Y.
2015-05-01
Context. The DANCe survey provides photometric and astrometric (position and proper motion) measurements for approximately 2 million unique sources in a region encompassing ~80 deg2 centered on the Pleiades cluster. Aims: We aim at deriving a complete census of the Pleiades and measure the mass and luminosity functions of the cluster. Methods: Using the probabilistic selection method previously described, we identified high probability members in the DANCe (i ≥ 14 mag) and Tycho-2 (V ≲ 12 mag) catalogues and studied the properties of the cluster over the corresponding luminosity range. Results: We find a total of 2109 high-probability members, of which 812 are new, making it the most extensive and complete census of the cluster to date. The luminosity and mass functions of the cluster are computed from the most massive members down to ~0.025 M⊙. The size, sensitivity, and quality of the sample result in the most precise luminosity and mass functions observed to date for a cluster. Conclusions: Our census supersedes previous studies of the Pleiades cluster populations, in terms of both sensitivity and accuracy. Based on service observations made with the William Herschel Telescope operated on the island of La Palma by the Isaac Newton Group in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias.Table 1 and Appendices are available in electronic form at http://www.aanda.orgDANCe catalogs (Tables 6 and 7) and full Tables 2-5 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/577/A148
DEFF Research Database (Denmark)
Bergami, Leonardo; Gaunaa, Mac; Heinz, Joachim Christian
2013-01-01
The aeroelastic response of wind turbines is often simulated in the time domain by using indicial response techniques. Unsteady aerodynamics in attached flow are usually based on Jones's approximation of the flat plate indicial response, although the response for finite‐thickness airfoils differs...... from the flat plate one. The indicial lift response of finite‐thickness airfoils is simulated with a panel code, and an empirical relation is outlined connecting the airfoil indicial response to its geometric characteristics. The effects of different indicial approximations are evaluated on a 2D...... of equivalent fatigue loads, ultimate loads, and stability limits. The agreement with CFD computations of a 2D profile in harmonic motion is improved by the indicial function accounting for the finite‐thickness of the airfoil. Concerning the full wind turbine aeroelastic behavior, the differences between...
Kurtz, Patricia F; Boelter, Eric W; Jarmolowicz, David P; Chin, Michelle D; Hagopian, Louis P
2011-01-01
This paper examines the literature on the use of functional communication training (FCT) as a treatment for problem behavior displayed by individuals with intellectual disabilities (ID). Criteria for empirically supported treatments developed by Divisions 12 and 16 of the American Psychological Association (Kratochwill & Stoiber, 2002; Task Force, 1995) and adapted by Jennett and Hagopian (2008) for evaluation of single-case research studies were used to examine the support for FCT. Results indicated that FCT far exceeds criteria to be designated as a well-established treatment for problem behavior exhibited by children with ID and children with autism spectrum disorder, and can be characterized as probably efficacious with adults. Copyright © 2011 Elsevier Ltd. All rights reserved.
A new empirical potential function and its application to hydrogen bonding
International Nuclear Information System (INIS)
Kang, Y.K.; Jhon, M.S.
1981-01-01
A new potential function based on spectroscopic results for diatomic molecules is presented and applied to the hydrogen bonding systems. The potential energy of interaction is supposed to have electrostatic, polarization, dispersion, repulsion and effective charge-transfer contributions. Estimates of the effective charge-transfer quantity have been made based on the average charge of the proton donor and the acceptor atoms. For dimers such as water, methanol, acetic acid and formic acid, the vibrational stretching frequencies and dimerization energies are calculated and discussed in connection with Badger-Bauer rule. (author)
Benzina, Amal
2012-01-01
Mobile phones provide an interesting all-in-one alternative for 3D input devices in virtual environments. Mobile phones are becoming touch sensitive and spatially aware, and they are now part of our daily activities. We present Phone-Based Motion Control, a novel one-handed travel technique for a virtual environment. The technique benefits from the touch capability offered by growing number of mobile phones to change viewpoint translation in virtual environments, while the orientation of the viewpoint is controlled by built-in sensors in the mobile phone. The travel interaction separates translation (touch based translation control) and rotation (steer based rotation control), putting each set of degrees of freedom (DOF) to a separate interaction technique (separability). This paper examines, how many DOF are needed to perform the travel task as easy and comfortable as possible. It also investigates different mapping functions between the user\\'s actions on the mobile phone and the viewpoint change in the virtual environment. Therefore, four techniques are implemented: rotate by heading, rotate by roll, rotate by roll with fixed horizon and a merged rotation. Each technique has either 4 or 5 DOF and different mappings between phone and viewpoint coordinates in the virtual environment. We perform an extensive user study to explore different aspects related to the travel techniques in terms of DOF and mapping functions. Results of the user evaluation show that 4 DOF techniques seem to perform better the travel task. Even though, the results were not statistically decisive in favor of the usage of the mobile roll to control the viewpoint heading in the virtual environment despite the good results, there is a clear tendency from the users to prefer the mobile roll as the desired mapping. Copyright 2012 ACM.
On Linear Combinations of Two Orthogonal Polynomial Sequences on the Unit Circle
Directory of Open Access Journals (Sweden)
Suárez C
2010-01-01
Full Text Available Let be a monic orthogonal polynomial sequence on the unit circle. We define recursively a new sequence of polynomials by the following linear combination: , , . In this paper, we give necessary and sufficient conditions in order to make be an orthogonal polynomial sequence too. Moreover, we obtain an explicit representation for the Verblunsky coefficients and in terms of and . Finally, we show the relation between their corresponding Carathéodory functions and their associated linear functionals.
Sign patterns of J-orthogonal matrices
Czech Academy of Sciences Publication Activity Database
Hall, F.J.; Li, Z.; Parnass, C.; Rozložník, Miroslav
2017-01-01
Roč. 5, č. 1 (2017), s. 225-241 ISSN 2300-7451 Institutional support: RVO:67985840 Keywords : G-matrix * J-orthogonal matrix * sign pattern matrix * sign patterns that allow J-orthogonality Subject RIV: BA - General Mathematics OBOR OECD: Applied mathematics https://www.degruyter.com/view/j/spma.2017.5.issue-1/spma-2017-0016/spma-2017-0016.xml?format=INT
Sign patterns of J-orthogonal matrices
Czech Academy of Sciences Publication Activity Database
Hall, F.J.; Li, Z.; Parnass, C.; Rozložník, Miroslav
2017-01-01
Roč. 5, č. 1 (2017), s. 225-241 ISSN 2300-7451 Institutional support: RVO:67985840 Keywords : G-matrix * J-orthogonal matrix * sign pattern matrix * sign patterns that allow J-orthogonality Subject RIV: BA - General Mathematics OBOR OECD: Applied mathematics https://www.degruyter.com/view/j/spma.2017.5.issue-1/spma-2017-0016/spma-2017-0016. xml ?format=INT
Directory of Open Access Journals (Sweden)
H. Rezghian Moghadam
2018-06-01
Full Text Available The tremor injury is one of the common symptoms of Parkinson's disease. The patients suffering from Parkinson's disease have difficulty in controlling their movements owing to tremor. The intensity of the disease can be determined through specifying the range of intensity values of involuntary tremor in Parkinson patients. The level of disease in patients is determined through an empirical range of 0-5. In the early stages of Parkinson, resting tremor can be very mild and intermittent. So, diagnosing the levels of disease is difficult but important since it has only medication therapy. The aim of this study is to quantify the intensity of tremor by the analysis of electromyogram signal. The solution proposed in this paper is to employ a polynomial function model to estimate the Unified Parkinson's Disease Rating Scale (UPDRS value. The algorithm of Fast Orthogonal Search (FOS, which is based on identification of orthogonal basic functions, was utilized for model identification. In fact, some linear and nonlinear features extracted from wrist surface electromyogram signal were considered as the input of the model identified by FOS, and the model output was the UPDRS value. In this research, the proposed model was designed based on two different structures which have been called the single structure and parallel structure. The efficiency of designed models with different structures was evaluated. The evaluation results using K-fold cross validation approach showed that the proposed model with a parallel structure could determine the tremor severity of the Parkinson's disease with accuracy of 99.25% ±0.41, sensitivity of 97.17% ±1.9 and specificity of 99.72% ±0.18.
Mejia, Amanda F; Nebel, Mary Beth; Barber, Anita D; Choe, Ann S; Pekar, James J; Caffo, Brian S; Lindquist, Martin A
2018-05-15
Reliability of subject-level resting-state functional connectivity (FC) is determined in part by the statistical techniques employed in its estimation. Methods that pool information across subjects to inform estimation of subject-level effects (e.g., Bayesian approaches) have been shown to enhance reliability of subject-level FC. However, fully Bayesian approaches are computationally demanding, while empirical Bayesian approaches typically rely on using repeated measures to estimate the variance components in the model. Here, we avoid the need for repeated measures by proposing a novel measurement error model for FC describing the different sources of variance and error, which we use to perform empirical Bayes shrinkage of subject-level FC towards the group average. In addition, since the traditional intra-class correlation coefficient (ICC) is inappropriate for biased estimates, we propose a new reliability measure denoted the mean squared error intra-class correlation coefficient (ICC MSE ) to properly assess the reliability of the resulting (biased) estimates. We apply the proposed techniques to test-retest resting-state fMRI data on 461 subjects from the Human Connectome Project to estimate connectivity between 100 regions identified through independent components analysis (ICA). We consider both correlation and partial correlation as the measure of FC and assess the benefit of shrinkage for each measure, as well as the effects of scan duration. We find that shrinkage estimates of subject-level FC exhibit substantially greater reliability than traditional estimates across various scan durations, even for the most reliable connections and regardless of connectivity measure. Additionally, we find partial correlation reliability to be highly sensitive to the choice of penalty term, and to be generally worse than that of full correlations except for certain connections and a narrow range of penalty values. This suggests that the penalty needs to be chosen carefully
International Nuclear Information System (INIS)
Li, M.; Li, X.
2005-01-01
The probabilistic distribution of wind speed is one of the important wind characteristics for the assessment of wind energy potential and for the performance of wind energy conversion systems, as well as for the structural and environmental design and analysis. In this study, an exponential family of distribution functions has been developed for the description of the probabilistic distribution of wind speed, and comparison with the wind speed data taken from different sources and measured at different geographical locations in the world has been made. This family of distributions is developed by introducing a pre-exponential term to the theoretical distribution derived from the Maximum Entropy Principle (MEP). The statistical analysis parameter based on the wind power density is used as the suitability judgement for the distribution functions. It is shown that the MEP-type distributions not only agree better with a variety of the measured wind speed data than the conventionally used empirical Weibull distribution, but also can represent the wind power density much more accurately. Therefore, the MEP-type distributions are more suitable for the assessment of the wind energy potential and the performance of wind energy conversion systems. (author)
Wałęga, Andrzej; Młyński, Dariusz; Wachulec, Katarzyna
2017-12-01
The aim of the study was to assess the applicability of asymptotic functions for determining the value of CN parameter as a function of precipitation depth in mountain and upland catchments. The analyses were carried out in two catchments: the Rudawa, left tributary of the Vistula, and the Kamienica, right tributary of the Dunajec. The input material included data on precipitation and flows for a multi-year period 1980-2012, obtained from IMGW PIB in Warsaw. Two models were used to determine empirical values of CNobs parameter as a function of precipitation depth: standard Hawkins model and 2-CN model allowing for a heterogeneous nature of a catchment area. The study analyses confirmed that asymptotic functions properly described P-CNobs relationship for the entire range of precipitation variability. In the case of high rainfalls, CNobs remained above or below the commonly accepted average antecedent moisture conditions AMCII. The study calculations indicated that the runoff amount calculated according to the original SCS-CN method might be underestimated, and this could adversely affect the values of design flows required for the design of hydraulic engineering projects. In catchments with heterogeneous land cover, the results of CNobs were more accurate when 2-CN model was used instead of the standard Hawkins model. 2-CN model is more precise in accounting for differences in runoff formation depending on retention capacity of the substrate. It was also demonstrated that the commonly accepted initial abstraction coefficient λ = 0.20 yielded too big initial loss of precipitation in the analyzed catchments and, therefore, the computed direct runoff was underestimated. The best results were obtained for λ = 0.05.
Kendler, K S
2012-04-01
Our tendency to see the world of psychiatric illness in dichotomous and opposing terms has three major sources: the philosophy of Descartes, the state of neuropathology in late nineteenth century Europe (when disorders were divided into those with and without demonstrable pathology and labeled, respectively, organic and functional), and the influential concept of computer functionalism wherein the computer is viewed as a model for the human mind-brain system (brain=hardware, mind=software). These mutually re-enforcing dichotomies, which have had a pernicious influence on our field, make a clear prediction about how 'difference-makers' (aka causal risk factors) for psychiatric disorders should be distributed in nature. In particular, are psychiatric disorders like our laptops, which when they dysfunction, can be cleanly divided into those with software versus hardware problems? I propose 11 categories of difference-makers for psychiatric illness from molecular genetics through culture and review their distribution in schizophrenia, major depression and alcohol dependence. In no case do these distributions resemble that predicted by the organic-functional/hardware-software dichotomy. Instead, the causes of psychiatric illness are dappled, distributed widely across multiple categories. We should abandon Cartesian and computer-functionalism-based dichotomies as scientifically inadequate and an impediment to our ability to integrate the diverse information about psychiatric illness our research has produced. Empirically based pluralism provides a rigorous but dappled view of the etiology of psychiatric illness. Critically, it is based not on how we wish the world to be but how the difference-makers for psychiatric illness are in fact distributed.
An Orthogonal Multi-Swarm Cooperative PSO Algorithm with a Particle Trajectory Knowledge Base
Directory of Open Access Journals (Sweden)
Jun Yang
2017-01-01
Full Text Available A novel orthogonal multi-swarm cooperative particle swarm optimization (PSO algorithm with a particle trajectory knowledge base is presented in this paper. Different from the traditional PSO algorithms and other variants of PSO, the proposed orthogonal multi-swarm cooperative PSO algorithm not only introduces an orthogonal initialization mechanism and a particle trajectory knowledge base for multi-dimensional optimization problems, but also conceives a new adaptive cooperation mechanism to accomplish the information interaction among swarms and particles. Experiments are conducted on a set of benchmark functions, and the results show its better performance compared with traditional PSO algorithm in aspects of convergence, computational efficiency and avoiding premature convergence.
Least squares orthogonal polynomial approximation in several independent variables
International Nuclear Information System (INIS)
Caprari, R.S.
1992-06-01
This paper begins with an exposition of a systematic technique for generating orthonormal polynomials in two independent variables by application of the Gram-Schmidt orthogonalization procedure of linear algebra. It is then demonstrated how a linear least squares approximation for experimental data or an arbitrary function can be generated from these polynomials. The least squares coefficients are computed without recourse to matrix arithmetic, which ensures both numerical stability and simplicity of implementation as a self contained numerical algorithm. The Gram-Schmidt procedure is then utilised to generate a complete set of orthogonal polynomials of fourth degree. A theory for the transformation of the polynomial representation from an arbitrary basis into the familiar sum of products form is presented, together with a specific implementation for fourth degree polynomials. Finally, the computational integrity of this algorithm is verified by reconstructing arbitrary fourth degree polynomials from their values at randomly chosen points in their domain. 13 refs., 1 tab
Interlacing of zeros of quasi-orthogonal meixner polynomials | Driver ...
African Journals Online (AJOL)
... interlacing of zeros of quasi-orthogonal Meixner polynomials Mn(x;β; c) with the zeros of their nearest orthogonal counterparts Mt(x;β + k; c), l; n ∈ ℕ, k ∈ {1; 2}; is also discussed. Mathematics Subject Classication (2010): 33C45, 42C05. Key words: Discrete orthogonal polynomials, quasi-orthogonal polynomials, Meixner
Lee, Jonathan A.
2010-01-01
High pressure Hydrogen (H) gas has been known to have a deleterious effect on the mechanical properties of certain metals, particularly, the notched tensile strength, fracture toughness and ductility. The ratio of these properties in Hydrogen as compared to Helium or Air is called the Hydrogen Environment Embrittlement (HEE) Index, which is a useful method to classify the severity of H embrittlement and to aid in the material screening and selection for safety usage H gas environment. A comprehensive world-wide database compilation, in the past 50 years, has shown that the HEE index is mostly collected at two conveniently high H pressure points of 5 ksi and 10 ksi near room temperature. Since H embrittlement is directly related to pressure, the lack of HEE index at other pressure points has posed a technical problem for the designers to select appropriate materials at a specific H pressure for various applications in aerospace, alternate and renewable energy sectors for an emerging hydrogen economy. Based on the Power-Law mathematical relationship, an empirical method to accurately predict the HEE index, as a function of H pressure at constant temperature, is presented with a brief review on Sievert's law for gas-metal absorption.
Orthogonal Coupling in Cavity BPM with Slots
Lipka, D; Siemens, M; Vilcins, S; Caspers, Friedhelm; Stadler, M; Treyer, DM; Maesaka, H; Shintake, T
2009-01-01
XFELs require high precision orbit control in their long undulator sections. Due to the pulsed operation of drive linacs the high precision has to be reached by single bunch measurements. So far only cavity BPMs achieve the required performance and will be used at the European XFEL, one between each of the up to 116 undulators. Coupling between the orthogonal planes limits the performance of beam position measurements. A first prototype build at DESY shows a coupling between orthogonal planes of about -20 dB, but the requirement is lower than -40 dB (1%). The next generation cavity BPM was build with tighter tolerances and mechanical changes, the orthogonal coupling is measured to be lower than -43 dB. This report discusses the various observations, measurements and improvements which were done.
Riemannian geometry in an orthogonal frame
Cartan, Elie Joseph
2001-01-01
Foreword by S S Chern. In 1926-27, Cartan gave a series of lectures in which he introduced exterior forms at the very beginning and used extensively orthogonal frames throughout to investigate the geometry of Riemannian manifolds. In this course he solved a series of problems in Euclidean and non-Euclidean spaces, as well as a series of variational problems on geodesics. In 1960, Sergei P Finikov translated from French into Russian his notes of these Cartan's lectures and published them as a book entitled Riemannian Geometry in an Orthogonal Frame. This book has many innovations, such as the n
Differential recurrence formulae for orthogonal polynomials
Directory of Open Access Journals (Sweden)
Anton L. W. von Bachhaus
1995-11-01
Full Text Available Part I - By combining a general 2nd-order linear homogeneous ordinary differential equation with the three-term recurrence relation possessed by all orthogonal polynomials, it is shown that sequences of orthogonal polynomials which satisfy a differential equation of the above mentioned type necessarily have a differentiation formula of the type: gn(xY'n(x=fn(xYn(x+Yn-1(x. Part II - A recurrence formula of the form: rn(xY'n(x+sn(xY'n+1(x+tn(xY'n-1(x=0, is derived using the result of Part I.
Matos, Catarina; Silveira, Graça; Custódio, Susana; Domingues, Ana; Dias, Nuno; Fonseca, João F. B.; Matias, Luís; Krueger, Frank; Carrilho, Fernando
2014-05-01
Noise cross-correlations are now widely used to extract Green functions between station pairs. But, do all the cross-correlations routinely computed produce successful Green Functions? What is the relationship between noise recorded in a couple of stations and the cross-correlation between them? During the last decade, we have been involved in the deployment of several temporary dense broadband (BB) networks within the scope of both national projects and international collaborations. From 2000 to 2002, a pool of 8 BB stations continuously operated in the Azores in the scope of the Memorandum of Understanding COSEA (COordinated Seismic Experiment in the Azores). Thanks to the Project WILAS (West Iberia Lithosphere and Astenosphere Structure, PTDC/CTE-GIX/097946/2008) we temporarily increased the number of BB deployed in mainland Portugal to more than 50 (permanent + temporary) during the period 2010 - 2012. In 2011/12 a temporary pool of 12 seismometers continuously recorded BB data in the Madeira archipelago, as part of the DOCTAR (Deep Ocean Test Array Experiment) project. Project CV-PLUME (Investigation on the geometry and deep signature of the Cape Verde mantle plume, PTDC/CTE-GIN/64330/2006) covered the archipelago of Cape Verde, North Atlantic, with 40 temporary BB stations in 2007/08. Project MOZART (Mozambique African Rift Tomography, PTDC/CTE-GIX/103249/2008), covered Mozambique, East Africa, with 30 temporary BB stations in the period 2011 - 2013. These networks, located in very distinct geographical and tectonic environments, offer an interesting opportunity to study seasonal and spatial variations of noise sources and their impact on Empirical Green functions computed from noise cross-correlation. Seismic noise recorded at different seismic stations is evaluated by computation of the probability density functions of power spectral density (PSD) of continuous data. To assess seasonal variations of ambient noise sources in frequency content, time-series of
Orthogonal polynomials in transport theories
International Nuclear Information System (INIS)
Dehesa, J.S.
1981-01-01
The asymptotical (k→infinity) behaviour of zeros of the polynomials gsub(k)sup((m)(ν)) encountered in the treatment of direct and inverse problems of scattering in neutron transport as well as radiative transfer theories is investigated in terms of the amplitude antiwsub(k) of the kth Legendre polynomial needed in the expansion of the scattering function. The parameters antiwsub(k) describe the anisotropy of scattering of the medium considered. In particular, it is shown that the asymptotical density of zeros of the polynomials gsub(k)sup(m)(ν) is an inverted semicircle for the anisotropic non-multiplying scattering medium
Nonclassical Orthogonal Polynomials and Corresponding Quadratures
Fukuda, H; Alt, E O; Matveenko, A V
2004-01-01
We construct nonclassical orthogonal polynomials and calculate abscissas and weights of Gaussian quadrature for arbitrary weight and interval. The program is written by Mathematica and it works if moment integrals are given analytically. The result is a FORTRAN subroutine ready to utilize the quadrature.
A new description of orthogonal bases
Coecke, Bob; Pavlovic, Dusko; Vicary, Jamie
2012-01-01
We show that an orthogonal basis for a finite-dimensional Hilbert space can be equivalently characterised as a commutative †-Frobenius monoid in the category FdHilb, which has finite-dimensional Hilbert spaces as objects and continuous linear maps as morphisms, and tensor product for the monoidal
A class of orthogonal nonrecursive binomial filters.
Haddad, R. A.
1971-01-01
The time- and frequency-domain properties of the orthogonal binomial sequences are presented. It is shown that these sequences, or digital filters based on them, can be generated using adders and delay elements only. The frequency-domain behavior of these nonrecursive binomial filters suggests a number of applications as low-pass Gaussian filters or as inexpensive bandpass filters.
Local copying of orthogonal entangled quantum states
International Nuclear Information System (INIS)
Anselmi, Fabio; Chefles, Anthony; Plenio, Martin B
2004-01-01
In classical information theory one can, in principle, produce a perfect copy of any input state. In quantum information theory, the no cloning theorem prohibits exact copying of non-orthogonal states. Moreover, if we wish to copy multiparticle entangled states and can perform only local operations and classical communication (LOCC), then further restrictions apply. We investigate the problem of copying orthogonal, entangled quantum states with an entangled blank state under the restriction to LOCC. Throughout, the subsystems have finite dimension D. We show that if all of the states to be copied are non-maximally entangled, then novel LOCC copying procedures based on entanglement catalysis are possible. We then study in detail the LOCC copying problem where both the blank state and at least one of the states to be copied are maximally entangled. For this to be possible, we find that all the states to be copied must be maximally entangled. We obtain a necessary and sufficient condition for LOCC copying under these conditions. For two orthogonal, maximally entangled states, we provide the general solution to this condition. We use it to show that for D = 2, 3, any pair of orthogonal, maximally entangled states can be locally copied using a maximally entangled blank state. However, we also show that for any D which is not prime, one can construct pairs of such states for which this is impossible
Zhang, W.; Zhang, Y.; Yao, X.
2010-12-01
On May 12, 2008, a huge earthquake with magnitude Ms8.0 occurred in the Wenhuan, Sichuan Province of China. This event was the most devastating earthquake in the mainland of China since the 1976 M7.8 Tangshan earthquake. It resulted in tremendous losses of life and property. There were about 90,000 persons killed. Due to occur in the mountainous area, this great earthquake and the following thousands aftershocks also caused many other geological disasters, such as landslide, mud-rock flow and “quake lakes” which formed by landslide-induced reservoirs. This earthquake occurred along the Longmenshan fault, as the result of motion on a northeast striking reverse fault or thrust fault on the northwestern margin of the Sichuan Basin. The earthquake's epicenter and focal-mechanism are consistent with it having occurred as the result of movement on the Longmenshan fault or a tectonically related fault. The earthquake reflects tectonic stresses resulting from the convergence of crustal material slowly moving from the high Tibetan Plateau, to the west, against strong crust underlying the Sichuan Basin and southeastern China. In this study, we simulate the near-field strong ground motions of this great event based on the empirical Green’s function method (EGF). Referring to the published inversion source models, at first, we assume that there are three asperities on the rupture area and choose three different small events as the EGFs. Then, we identify the parameters of the source model using a genetic algorithm (GA). We calculate the synthetic waveforms based on the obtained source model and compare with the observed records. Our result shows that for most of the synthetic waveforms agree very well with the observed ones. The result proves the validity and the stability of the method. Finally, we forward the near-field strong ground motions near the source region and try to explain the damage distribution caused by the great earthquake.
DEFF Research Database (Denmark)
Khair, Tabish
2017-01-01
Review of 'Inglorious Empire: What the British did to India' by Shashi Tharoor, London, Hurst Publishers, 2017, 296 pp., £20.00......Review of 'Inglorious Empire: What the British did to India' by Shashi Tharoor, London, Hurst Publishers, 2017, 296 pp., £20.00...
The Fractional Orthogonal Difference with Applications
Directory of Open Access Journals (Sweden)
Enno Diekema
2015-06-01
Full Text Available This paper is a follow-up of a previous paper of the author published in Mathematics journal in 2015, which treats the so-called continuous fractional orthogonal derivative. In this paper, we treat the discrete case using the fractional orthogonal difference. The theory is illustrated with an application of a fractional differentiating filter. In particular, graphs are presented of the absolutel value of the modulus of the frequency response. These make clear that for a good insight into the behavior of a fractional differentiating filter, one has to look for the modulus of its frequency response in a log-log plot, rather than for plots in the time domain.
HOLA: Human-like Orthogonal Network Layout.
Kieffer, Steve; Dwyer, Tim; Marriott, Kim; Wybrow, Michael
2016-01-01
Over the last 50 years a wide variety of automatic network layout algorithms have been developed. Some are fast heuristic techniques suitable for networks with hundreds of thousands of nodes while others are multi-stage frameworks for higher-quality layout of smaller networks. However, despite decades of research currently no algorithm produces layout of comparable quality to that of a human. We give a new "human-centred" methodology for automatic network layout algorithm design that is intended to overcome this deficiency. User studies are first used to identify the aesthetic criteria algorithms should encode, then an algorithm is developed that is informed by these criteria and finally, a follow-up study evaluates the algorithm output. We have used this new methodology to develop an automatic orthogonal network layout method, HOLA, that achieves measurably better (by user study) layout than the best available orthogonal layout algorithm and which produces layouts of comparable quality to those produced by hand.
Characterizing locally distinguishable orthogonal product states
Feng, Yuan; Shi, Yaoyun
2007-01-01
Bennett et al. \\cite{BDF+99} identified a set of orthogonal {\\em product} states in the $3\\otimes 3$ Hilbert space such that reliably distinguishing those states requires non-local quantum operations. While more examples have been found for this counter-intuitive ``nonlocality without entanglement'' phenomenon, a complete and computationally verifiable characterization for all such sets of states remains unknown. In this Letter, we give such a characterization for the $3\\otimes 3$ space.
Rotation of 2D orthogonal polynomials
Czech Academy of Sciences Publication Activity Database
Yang, B.; Flusser, Jan; Kautský, J.
2018-01-01
Roč. 102, č. 1 (2018), s. 44-49 ISSN 0167-8655 R&D Projects: GA ČR GA15-16928S Institutional support: RVO:67985556 Keywords : Rotation invariants * Orthogonal polynomials * Recurrent relation * Hermite-like polynomials * Hermite moments Subject RIV: JD - Computer Applications, Robotics Impact factor: 1.995, year: 2016 http://library.utia.cas.cz/separaty/2017/ZOI/flusser-0483250.pdf
Non-Orthogonal Opportunistic Beamforming: Performance Analysis and Implementation
Xia, Minghua; Wu, Yik-Chung; Aissa, Sonia
2012-01-01
be successfully served within a single transmission, non-orthogonal OBF can be applied to obtain lower worst-case delay among the users. On the other hand, if user traffic is heavy, non-orthogonal OBF is inferior to orthogonal OBF in terms of sum-rate and packet
The construction of a class of trivariate nonseparable compactly supported orthogonal wavelets
International Nuclear Information System (INIS)
Huang Yongdong; Lei Chongmin; Yang Miao
2009-01-01
In this paper, under a mild condition, the construction of compactly supported orthogonal wavelets is obtained. Wavelets inherit the symmetry of the corresponding scaling function and satisfy the vanishing moment condition originating in the symbols of the scaling function. An example is also given to demonstrate the general theory.
Energy Technology Data Exchange (ETDEWEB)
Manokhin, Vassily N. [Russian Nuclear Data Center, Institute of Physics and Power Engineering, Obninsk (Russian Federation); Odano, Naoteru; Hasegawa, Akira [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment
2001-03-01
An approach for consistent evaluation of (n,2n) and (n,np) reaction excitation functions for some even-even isotopes with the (n,np) reaction thresholds lower than (n,2n) reaction ones is described. For determination of cross sections in the maximum of the (n,2n) and (n,np) reaction excitation functions some empirical systematics developed by Manokhin were used together with trends in dependence of gaps between the (n,2n) and (n,np) thresholds on atomic mass number A. The shapes of the (n,2n) and (n,np) reaction excitation functions were calculated using the normalized functions from the Manokhin's systematics. Excitation functions of (n,2n) and (n,np) reactions were evaluated for several nuclei by using the systematics and it was found that the approach used for the present study gives reasonable results. (author)
Integrated, Dual Orthogonal Antennas for Polarimetric Ground Penetrating Radar
Pauli, Mario; Wiesbeck, Werner
2015-04-01
developed [4]. If OFDM signals are used for the radiation, the carriers can be split in even and odd carriers and fed to the two orthogonally polarized transmit antennas. By using OFDM, the de-correlation of the two subcarrier groups becomes inherently high. Due to the orthogonality of OFDM subcarriers the de-correlation only depends on the quality of the hardware and the signal processing. They can be simultaneously radiated and received by the two antennas. This could result in a significant improvement of the GPR sensor system. The antenna has been realized and first measurements have been conducted. During the forthcoming EGU 2015 General Assembly the detailed electromagnetic background and the function of the dual linear, orthogonal polarized antenna will be presented as well as results in GPR relevant frequencies. Also, an approach of a planar feeding network will be presented. This abstract is a contribution to Session GI3.1 "Civil Engineering Applications of Ground Penetrating Radar," organized by the COST Action TU1208. References [1] Carin, L.; Kapoor, R.; Baum, C.E., "Polarimetric SAR imaging of buried landmines," IEEE Transactions on Geoscience and Remote Sensing, vol. 36 iss. 6, pp.1985-1988, 1998. [2] T. Schultze, M. Porebska, W. Wiesbeck, and I. Willms, "Onsets for the recognition of objects and image refinement using UWB Radar," in Proceedings of the German Microwave Conference GeMiC 2008, CD-ROM, Hamburg-Harburg, Germany, Mar. 2008. [3] G. Adamiuk, S. Beer, W. Wiesbeck, and T. Zwick, "Dual-Orthogonal Polarized Antenna for UWB-IR Technology," IEEE Antennas and Wireless Propagation Letters, vol. 8, pp. 981-984, Jul. 2009. [4] Adamiuk, W. Wiesbeck, and T. Zwick, "Differential Feeding as a Concept for the Realization of Broadband Dual-Polarized Antennas with Very High Polarization Purity," in 2009 IEEE International Symposium on Antennas & Propagation, Charleston, South Carolina, USA, Jun. 2009.
Method of orthogonally splitting imaging pose measurement
Zhao, Na; Sun, Changku; Wang, Peng; Yang, Qian; Liu, Xintong
2018-01-01
In order to meet the aviation's and machinery manufacturing's pose measurement need of high precision, fast speed and wide measurement range, and to resolve the contradiction between measurement range and resolution of vision sensor, this paper proposes an orthogonally splitting imaging pose measurement method. This paper designs and realizes an orthogonally splitting imaging vision sensor and establishes a pose measurement system. The vision sensor consists of one imaging lens, a beam splitter prism, cylindrical lenses and dual linear CCD. Dual linear CCD respectively acquire one dimensional image coordinate data of the target point, and two data can restore the two dimensional image coordinates of the target point. According to the characteristics of imaging system, this paper establishes the nonlinear distortion model to correct distortion. Based on cross ratio invariability, polynomial equation is established and solved by the least square fitting method. After completing distortion correction, this paper establishes the measurement mathematical model of vision sensor, and determines intrinsic parameters to calibrate. An array of feature points for calibration is built by placing a planar target in any different positions for a few times. An terative optimization method is presented to solve the parameters of model. The experimental results show that the field angle is 52 °, the focus distance is 27.40 mm, image resolution is 5185×5117 pixels, displacement measurement error is less than 0.1mm, and rotation angle measurement error is less than 0.15°. The method of orthogonally splitting imaging pose measurement can satisfy the pose measurement requirement of high precision, fast speed and wide measurement range.
q-analogue of the Krawtchouk and Meixner orthogonal polynomials
International Nuclear Information System (INIS)
Campigotto, C.; Smirnov, Yu.F.; Enikeev, S.G.
1993-06-01
The comparative analysis of Krawtchouk polynomials on a uniform grid with Wigner D-functions for the SU(2) group is presented. As a result the partnership between corresponding properties of the polynomials and D-functions is established giving the group-theoretical interpretation of the Krawtchouk polynomials properties. In order to extend such an analysis on the quantum groups SU q (2) and SU q (1,1), q-analogues of Krawtchouk and Meixner polynomials of a discrete variable are studied. The total set of characteristics of these polynomials is calculated, including the orthogonality condition, normalization factor, recurrent relation, the explicit analytic expression, the Rodrigues formula, the difference derivative formula and various particular cases and values. (R.P.) 22 refs.; 2 tabs
Farrance, Ian; Frenkel, Robert
2014-01-01
The Guide to the Expression of Uncertainty in Measurement (usually referred to as the GUM) provides the basic framework for evaluating uncertainty in measurement. The GUM however does not always provide clearly identifiable procedures suitable for medical laboratory applications, particularly when internal quality control (IQC) is used to derive most of the uncertainty estimates. The GUM modelling approach requires advanced mathematical skills for many of its procedures, but Monte Carlo simulation (MCS) can be used as an alternative for many medical laboratory applications. In particular, calculations for determining how uncertainties in the input quantities to a functional relationship propagate through to the output can be accomplished using a readily available spreadsheet such as Microsoft Excel. The MCS procedure uses algorithmically generated pseudo-random numbers which are then forced to follow a prescribed probability distribution. When IQC data provide the uncertainty estimates the normal (Gaussian) distribution is generally considered appropriate, but MCS is by no means restricted to this particular case. With input variations simulated by random numbers, the functional relationship then provides the corresponding variations in the output in a manner which also provides its probability distribution. The MCS procedure thus provides output uncertainty estimates without the need for the differential equations associated with GUM modelling. The aim of this article is to demonstrate the ease with which Microsoft Excel (or a similar spreadsheet) can be used to provide an uncertainty estimate for measurands derived through a functional relationship. In addition, we also consider the relatively common situation where an empirically derived formula includes one or more ‘constants’, each of which has an empirically derived numerical value. Such empirically derived ‘constants’ must also have associated uncertainties which propagate through the functional
Farrance, Ian; Frenkel, Robert
2014-02-01
The Guide to the Expression of Uncertainty in Measurement (usually referred to as the GUM) provides the basic framework for evaluating uncertainty in measurement. The GUM however does not always provide clearly identifiable procedures suitable for medical laboratory applications, particularly when internal quality control (IQC) is used to derive most of the uncertainty estimates. The GUM modelling approach requires advanced mathematical skills for many of its procedures, but Monte Carlo simulation (MCS) can be used as an alternative for many medical laboratory applications. In particular, calculations for determining how uncertainties in the input quantities to a functional relationship propagate through to the output can be accomplished using a readily available spreadsheet such as Microsoft Excel. The MCS procedure uses algorithmically generated pseudo-random numbers which are then forced to follow a prescribed probability distribution. When IQC data provide the uncertainty estimates the normal (Gaussian) distribution is generally considered appropriate, but MCS is by no means restricted to this particular case. With input variations simulated by random numbers, the functional relationship then provides the corresponding variations in the output in a manner which also provides its probability distribution. The MCS procedure thus provides output uncertainty estimates without the need for the differential equations associated with GUM modelling. The aim of this article is to demonstrate the ease with which Microsoft Excel (or a similar spreadsheet) can be used to provide an uncertainty estimate for measurands derived through a functional relationship. In addition, we also consider the relatively common situation where an empirically derived formula includes one or more 'constants', each of which has an empirically derived numerical value. Such empirically derived 'constants' must also have associated uncertainties which propagate through the functional relationship
Energy Technology Data Exchange (ETDEWEB)
Fain, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires
1963-05-15
A completely ionised medium is considered in which the variations of the distribution functions for each species of particles is governed by the Fokker-Planck equation. The interaction operator is of a form given by Rosenbluth - Macdonald - Judd. The distribution functions are expanded into orthogonal polynomial series in the velocity space. In a first stage these functions are first split up into spherical harmonic series (or, in an equivalent form, into series of scalar products of irreducible cartesian tensors), with coefficients which are a function of the velocity modulus as well as space and time coordinates. In the second stage these coefficients are expanded into series of orthogonal functions of the velocity modulus; the 1 order harmonic is represented by the product of a Maxwell distribution and of a SONINE polynomial series, having an index of 1 + 1 / 2, which have as variable the reduced energy of the particles (in terms of a basic temperature), with coefficients which then only depend on the space and time coordinates. In the first part the relationship is established between the expansion coefficients and the moments of the distribution function, as well as the hydrodynamic values. In the second part the expansion using spherical harmonics is applied to the Fokker-Planck equation. The general expression for the second member is given as well as the particular expressions corresponding to the cases where the operator is linearized. In the third part the complete expansion in orthogonal polynomial series is applied to the Fokker-Planck equation. The expression of the generating functions is given for all the harmonics in the case of the linearized operator, as well as the transport equations for the first four harmonics. (author) [French] On considere un milieu completement ionise ou l'evolution des fonctions de distribution pour chaque espece de particules est regie par l'equation de FOKKER-PLANCK. L'operateur d'interaction se met sous la forme
Gerrard, Simon R.
2012-10-23
Thermodynamic instability is a problem when assembling and purifying complex DNA nanostructures formed by hybridization alone. To address this issue, we have used photochemical fixation and orthogonal copper-free, ring-strain-promoted, click chemistry for the synthesis of dimeric, trimeric, and oligomeric modular DNA scaffolds from cyclic, double-stranded, 80-mer DNA nanoconstructs. This particular combination of orthogonal click reactions was more effective for nanoassembly than others explored. The complex nanostructures are stable to heat and denaturation agents and can therefore be purified and characterized. They are addressable in a sequence-specific manner by triplex formation, and they can be reversibly and selectively deconstructed. Nanostructures utilizing this orthogonal, chemical fixation methodology can be used as building blocks for nanomachines and functional DNA nanoarchitectures. © 2012 American Chemical Society.
International Nuclear Information System (INIS)
Pilati, T.; Dermartin, F.; Gramaccioli, C.M.
1993-01-01
A wide-purpose computer program has been written (Fortran) for lattice dynamical evaluation of crystallographic and thermodynamic properties of solids, especially minerals or inorganic substances.The program essentially consists of a routine affording first and second derivatives of energy with respect to mass weighted coordinates, properly modulated by a wave vector algorithm, so that diagonalization can immediately follow and arrive at frequencies, density of states, and eventually to thermodynamic functions and Debye-Waller parameters thorough an automatic Brillouin-zone sampling procedure. The input consists of crystallographic data (unit-cell parameters, space group symmetry operations, atomic coordinates), plus atomic charge and empirical parameters, such as force constants or non-bonded atom-atom interaction energy functions in almost any form. It is also possible to obtain the structure corresponding to the energy minimum, or even to work with partial rigid bodies, in order to reduce the order of the dynamical matrices. The program provides for automatic symmetry labelling of the vibrational modes, in order to compare them with the experimental data; there is possibility of improving the empirical functions through a minimization routine. Examples of application and transferability of force fields to a series of minerals are provided. (author)
Gabor's signal expansion based on a non-orthogonal sampling geometry
Bastiaans, M.J.; Caulfield, H. J.
2002-01-01
Gabor’s signal expansion and the Gabor transform are formulated on a nonorthogonal time-frequency lattice instead of on the traditional rectangular lattice. The reason for doing so is that a non-orthogonal sampling geometry might be better adapted to the form of the window functions (in the
Deformation of the three-term recursion relation and generation of new orthogonal polynomials
International Nuclear Information System (INIS)
Alhaidari, A D
2002-01-01
We find solutions for a linear deformation of the three-term recursion relation. The orthogonal polynomials of the first and second kind associated with the deformed relation are obtained. The new density (weight) function is written in terms of the original one and the deformation parameters
A novel orthogonally linearly polarized Nd:YVO4 laser
International Nuclear Information System (INIS)
Xing-Peng, Yan; Qiang, Liu; Hai-Long, Chen; Xing, Fu; Ma-Li, Gong; Dong-Sheng, Wang
2010-01-01
We presented a novel orthogonally linearly polarized Nd:YVO 4 laser. Two pieces of α-cut grown-together composite YVO 4 /Nd:YVO 4 crystals were placed in the resonant cavity with the c-axis of the two crystals orthogonally. The polarization and power performance of the orthogonally polarized laser were investigated. A 26.2-W orthogonally linearly polarized laser was obtained. The power ratio between the two orthogonally polarized lasers was varied with the pump power caused by the polarized mode coupling. The longitudinal modes competition and the corresponding variable optical beats were also observed from the orthogonally polarized laser. We also adjusted the crystals with their c-axis parallele to each other, and a 40.7-W linearly polarized TEM 00 laser was obtained, and the beam quality factors were M x 2 = 1.37 and M y 2 = 1.25. (classical areas of phenomenology)
Relativistic resonances as non-orthogonal states in Hilbert space
Blum, W
2003-01-01
We analyze the energy-momentum properties of relativistic short-lived particles with the result that they are characterized by two 4-vectors: in addition to the familiar energy-momentum vector (timelike) there is an energy-momentum 'spread vector' (spacelike). The wave functions in space and time for unstable particles are constructed. For the relativistic properties of unstable states we refer to Wigner's method of Poincare group representations that are induced by representations of the space-time translation and rotation groups. If stable particles, unstable particles and resonances are treated as elementary objects that are not fundamentally different one has to take into account that they will not generally be orthogonal to each other in their state space. The scalar product between a stable and an unstable state with otherwise identical properties is calculated in a particular Lorentz frame. The spin of an unstable particle is not infinitely sharp but has a 'spin spread' giving rise to 'spin neighbors'....
International Nuclear Information System (INIS)
Peggs, S.; Talman, R.
1987-01-01
As proton accelerators get larger, and include more magnets, the conventional tracking programs which simulate them run slower. The purpose of this paper is to describe a method, still under development, in which element-by-element tracking around one turn is replaced by a single man, which can be processed far faster. It is assumed for this method that a conventional program exists which can perform faithful tracking in the lattice under study for some hundreds of turns, with all lattice parameters held constant. An empirical map is then generated by comparison with the tracking program. A procedure has been outlined for determining an empirical Hamiltonian, which can represent motion through many nonlinear kicks, by taking data from a conventional tracking program. Though derived by an approximate method this Hamiltonian is analytic in form and can be subjected to further analysis of varying degrees of mathematical rigor. Even though the empirical procedure has only been described in one transverse dimension, there is good reason to hope that it can be extended to include two transverse dimensions, so that it can become a more practical tool in realistic cases
Higher spin currents in orthogonal Wolf space
International Nuclear Information System (INIS)
Ahn, Changhyun; Paeng, Jinsub
2015-01-01
For the N=4 superconformal coset theory by ((SO(N+4))/(SO(N)×SU(2)))×U(1) (that contains an orthogonal Wolf space) with N = 4, the N=2 WZW affine current algebra is obtained. The 16 generators (or 11 generators) of the large N=4 linear (or nonlinear) superconformal algebra are described by these WZW affine currents explicitly. Along the line of large N=4 holography, the extra 16 currents with spins (2,(5/2),(5/2),3), ((5/2),3,3,(7/2)), ((5/2),3,3,(7/2)), and (3,(7/2),(7/2),4) are obtained in terms of the WZW affine currents. The lowest spin of this N=4 multiplet is two rather than one, which is for a unitary Wolf space. The operator product expansions between the above 11 currents and these extra 16 higher spin currents are found explicitly. (paper)
Orthogonal cutting of laser beam melted parts
Götze, Elisa; Zanger, Frederik; Schulze, Volker
2018-05-01
The finishing process of parts manufactured by laser beam melting is of high concern due to the lack of surface accuracy. Therefore, the focus of this work lies on the influence of the build-up direction of the parts and their effect on the finishing process. The orthogonal cutting reveals findings in the fields of chip formation, involved forces and temperatures appearing during machining. In the investigations, the cutting depth was varied between 0.05 and 0.15 mm representing a finishing process and the cutting velocity ranges from 30 to 200 m/min depending on the material. The experiments contain the materials stainless steel (AISI 316L), titanium (Ti6Al4V) and nickel-base alloy (IN718). The two materials named latter are of high interest in the aerospace sector and at the same time titanium is used in the medical field due to its biocompatibility. For the materials IN718 and Ti6Al4V a negative rake angle of -7.5° and for stainless steel a rake angle of 12.5° are chosen for the cutting experiments. The results provide the base for processing strategies. Therefore, the specimens were solely laser beam melted without post-processing like heat treatment. The evaluation of the experiments shows that an increase in cutting speed has different effects depending on the material. For stainless steel the measured forces regarding the machining direction to the layers approach the same values. In contrast, the influence of the layers regarding the forces appearing during orthogonal cutting of the materials IN718 and Ti6Al4V differ for lower cutting speeds.
Nitsch, Renate; Fredebohm, Anneke; Bruder, Regina; Kelava, Augustin; Naccarella, Dominik; Leuders, Timo; Wirtz, Markus
2015-01-01
In the subject matter of functional relationships, a student's ability to translate from one form of representation to another is seen as a central competence. In the course of the HEUREKO project (heuristic work with representations of functional relationships and the diagnosis of mathematical competencies of students), a theoretical competence…
Wilbraham, Liam; Adamo, Carlo; Ciofini, Ilaria
2018-01-01
The computationally assisted, accelerated design of inorganic functional materials often relies on the ability of a given electronic structure method to return the correct electronic ground state of the material in question. Outlining difficulties with current density functionals and wave function-based approaches, we highlight why double hybrid density functionals represent promising candidates for this purpose. In turn, we show that PBE0-DH (and PBE-QIDH) offers a significant improvement over its hybrid parent functional PBE0 [as well as B3LYP* and coupled cluster singles and doubles with perturbative triples (CCSD(T))] when computing spin-state splitting energies, using high-level diffusion Monte Carlo calculations as a reference. We refer to the opposing influence of Hartree-Fock (HF) exchange and MP2, which permits higher levels of HF exchange and a concomitant reduction in electronic density error, as the reason for the improved performance of double-hybrid functionals relative to hybrid functionals. Additionally, using 16 transition metal (Fe and Co) complexes, we show that low-spin states are stabilised by increasing contributions from MP2 within the double hybrid formulation. Furthermore, this stabilisation effect is more prominent for high field strength ligands than low field strength ligands.
Some Bounds for the Logarithmic Function
DEFF Research Database (Denmark)
Topsøe, Flemming
2007-01-01
Development in continued fraction, rational approximations and orthogonal polynomials in relation to the logarithmic function are discussed.......Development in continued fraction, rational approximations and orthogonal polynomials in relation to the logarithmic function are discussed....
Blount, Benjamin A; Weenink, Tim; Vasylechko, Serge; Ellis, Tom
2012-01-01
Yeast is an ideal organism for the development and application of synthetic biology, yet there remain relatively few well-characterised biological parts suitable for precise engineering of this chassis. In order to address this current need, we present here a strategy that takes a single biological part, a promoter, and re-engineers it to produce a fine-graded output range promoter library and new regulated promoters desirable for orthogonal synthetic biology applications. A highly constitutive Saccharomyces cerevisiae promoter, PFY1p, was identified by bioinformatic approaches, characterised in vivo and diversified at its core sequence to create a 36-member promoter library. TetR regulation was introduced into PFY1p to create a synthetic inducible promoter (iPFY1p) that functions in an inverter device. Orthogonal and scalable regulation of synthetic promoters was then demonstrated for the first time using customisable Transcription Activator-Like Effectors (TALEs) modified and designed to act as orthogonal repressors for specific PFY1-based promoters. The ability to diversify a promoter at its core sequences and then independently target Transcription Activator-Like Orthogonal Repressors (TALORs) to virtually any of these sequences shows great promise toward the design and construction of future synthetic gene networks that encode complex "multi-wire" logic functions.
Blount, Benjamin A.; Weenink, Tim; Vasylechko, Serge; Ellis, Tom
2012-01-01
Yeast is an ideal organism for the development and application of synthetic biology, yet there remain relatively few well-characterised biological parts suitable for precise engineering of this chassis. In order to address this current need, we present here a strategy that takes a single biological part, a promoter, and re-engineers it to produce a fine-graded output range promoter library and new regulated promoters desirable for orthogonal synthetic biology applications. A highly constitutive Saccharomyces cerevisiae promoter, PFY1p, was identified by bioinformatic approaches, characterised in vivo and diversified at its core sequence to create a 36-member promoter library. TetR regulation was introduced into PFY1p to create a synthetic inducible promoter (iPFY1p) that functions in an inverter device. Orthogonal and scalable regulation of synthetic promoters was then demonstrated for the first time using customisable Transcription Activator-Like Effectors (TALEs) modified and designed to act as orthogonal repressors for specific PFY1-based promoters. The ability to diversify a promoter at its core sequences and then independently target Transcription Activator-Like Orthogonal Repressors (TALORs) to virtually any of these sequences shows great promise toward the design and construction of future synthetic gene networks that encode complex “multi-wire” logic functions. PMID:22442681
Representations for the extreme zeros of orthogonal polynomials
van Doorn, Erik A.; van Foreest, Nicky D.; Zeifman, Alexander I.
2009-01-01
We establish some representations for the smallest and largest zeros of orthogonal polynomials in terms of the parameters in the three-terms recurrence relation. As a corollary we obtain representations for the endpoints of the true interval of orthogonality. Implications of these results for the
Construction of MDS self-dual codes from orthogonal matrices
Shi, Minjia; Sok, Lin; Solé, Patrick
2016-01-01
In this paper, we give algorithms and methods of construction of self-dual codes over finite fields using orthogonal matrices. Randomization in the orthogonal group, and code extension are the main tools. Some optimal, almost MDS, and MDS self-dual codes over both small and large prime fields are constructed.
Processing of dual-orthogonal cw polarimetric radar signals
Babur, G.
2009-01-01
The thesis consists of two parts. The first part is devoted to the theory of dual-orthogonal polarimetric radar signals with continuous waveforms. The thesis presents a comparison of the signal compression techniques, namely correlation and de-ramping methods, for the dual-orthogonal sophisticated
Lechler, Suzanne; Hare, Dougal Julian
2015-01-01
A naturalistic observational single case study was carried out to investigate the form and function of private speech (PS) in a young man with Dandy-Walker variant syndrome and trisomy 22. Video recordings were observed, transcribed and coded to identify all combinations of type and form of PS. Through comparison between theories of PS and the…
Mandara, Jelani
2006-01-01
This article reviews and clarifies many inconsistencies and misconceptions in the research literature on the effects of family functioning on African American male academic achievement. It was concluded that when parents use an African American version of authoritative parenting, teach children about their cultural heritage and personal power to…
Stewart, F A
2011-10-01
All great apes build nightly a structure ("nest" or "bed") that is assumed to function primarily as a sleeping-platform. However, several other nest function hypotheses have been proposed: antipredation, antipathogen, and thermoregulation. I tested these simple shelter functions of chimpanzee nests in an experiment for which I was the subject in Fongoli, Senegal. I slept 11 nights in chimpanzee nests and on the bare ground to test for differences in sleep quality, potential exposure to disease through bites from possible vectors, and insulation. No difference was found in the total amount of sleep nor in sleep quality; however, sleep was more disturbed on the ground. Differences in sleep disturbance between arboreal and ground conditions seemed primarily due to causes of anxiety and alertness, e.g., vocalizations of terrestrial mammals. Arboreal nest-sleeping seems to reduce risk of bites from possible disease vectors and provide insulation in cold conditions. This preliminary, but direct, test of chimpanzee nest function has implications for the evolutionary transition from limb-roosting to nest-reclining sleep in the hominoids, and from tree-to-ground sleep in the genus Homo. Copyright © 2011 Wiley-Liss, Inc.
Strict optical orthogonal codes for purely asynchronous code-division multiple-access applications
Zhang, Jian-Guo
1996-12-01
Strict optical orthogonal codes are presented for purely asynchronous optical code-division multiple-access (CDMA) applications. The proposed code can strictly guarantee the peaks of its cross-correlation functions and the sidelobes of any of its autocorrelation functions to have a value of 1 in purely asynchronous data communications. The basic theory of the proposed codes is given. An experiment on optical CDMA systems is also demonstrated to verify the characteristics of the proposed code.
Nonambipolarity, orthogonal conductivity, poloidal flow, and torque
International Nuclear Information System (INIS)
Hulbert, G.W.; Perkins, F.W.
1989-02-01
Nonambipolar processes, such as neutral injection onto trapped orbits or ripple-diffusion loss of α-particles, act to charge a plasma. A current j/sub r/ across magnetic surfaces must arise in the bulk plasma to maintain charge neutrality. An axisymmetric, neoclassical model of the bulk plasma shows that these currents are carried by the ions and exert a j/sub r/B/sub θ/R/c torque in the toroidal direction. A driven poloidal flow V/sub θ/ = E/sub r/'c/B must also develop. The average current density is related to the radial electric field E/sub r/' = E/sub r/ + v/sub /phi//B/sub θ//c in a frame moving with the plasma via the orthogonal conductivity = σ/sub /perpendicular//E/sub r/', which has the value σ/sub /perpendicular// = (1.65ε/sup 1/2/)(ne 2 ν/sub ii//MΩ/sub θ/ 2 ) in the banana regime. If an ignited plasma loses an appreciable fraction Δ of its thermonuclear α-particles by banana ripple diffusion, then the torque will spin the plasma to sonic rotation in a time /tau//sub s/ ∼ 2/tau//sub E//Δ, /tau//sub E/ being the energy confinement time. 10 refs., 1 fig
Directory of Open Access Journals (Sweden)
Marek RUTKOWSKI
2014-12-01
Full Text Available This article deals with the issues of borde bridges connecting till the mid of 19th century Kingdom of Poland and tzarist Russian Empire in three main points: Aleksota, Terespol and Źółtki towns. The different aspects of functioning of these bridges were analyzed, including a chronological view of the phenomenon; as well one drew attention to visible and clear tendency in their management. A repeated idea tended to occcur as - especially since the period of “Spring of Nations” - one could observe among Russian authorities kind of steady desire to take full controll over Polish- Russian border bridges from Polish hands and make them subject to the imperial rule of military or civilian origin only.
P A M Dirac meets M G Krein: matrix orthogonal polynomials and Dirac's equation
International Nuclear Information System (INIS)
Duran, Antonio J; Gruenbaum, F Alberto
2006-01-01
The solution of several instances of the Schroedinger equation (1926) is made possible by using the well-known orthogonal polynomials associated with the names of Hermite, Legendre and Laguerre. A relativistic alternative to this equation was proposed by Dirac (1928) involving differential operators with matrix coefficients. In 1949 Krein developed a theory of matrix-valued orthogonal polynomials without any reference to differential equations. In Duran A J (1997 Matrix inner product having a matrix symmetric second order differential operator Rocky Mt. J. Math. 27 585-600), one of us raised the question of determining instances of these matrix-valued polynomials going along with second order differential operators with matrix coefficients. In Duran A J and Gruenbaum F A (2004 Orthogonal matrix polynomials satisfying second order differential equations Int. Math. Res. Not. 10 461-84), we developed a method to produce such examples and observed that in certain cases there is a connection with the instance of Dirac's equation with a central potential. We observe that the case of the central Coulomb potential discussed in the physics literature in Darwin C G (1928 Proc. R. Soc. A 118 654), Nikiforov A F and Uvarov V B (1988 Special Functions of Mathematical Physics (Basle: Birkhauser) and Rose M E 1961 Relativistic Electron Theory (New York: Wiley)), and its solution, gives rise to a matrix weight function whose orthogonal polynomials solve a second order differential equation. To the best of our knowledge this is the first instance of a connection between the solution of the first order matrix equation of Dirac and the theory of matrix-valued orthogonal polynomials initiated by M G Krein
An Empirical Study on Rural Economic Growth in Hubei Province Based on New C-D Production Function
Institute of Scientific and Technical Information of China (English)
Yi; WEN; Minghong; CAO
2016-01-01
Human capital is becoming a major driving force of promoting economic growth and social development. Hubei Province as a large agricultural province is significantly affected by the human capital. The paper selects the correlation data about rural economic growth in Hubei Province as samples to analyze the contribution of physical capital and human capital to rural economic growth by the new C-D function and SPSS22. 0. The results show that the effect of the elasticity of human capital is greater than that of physical capital in rural economic development; the high quality rural human capital storage and the average years of schooling of rural labor force will increase the net income of rural household. Therefore,we should not only increase input of physical capital but also increase the input of human capital to raise the level of human capital in rural areas and promote sustainable development of rural economy.
Perenboom, Rom J M; Wijlhuizen, Gert Jan; Garre, Francisca Galindo; Heerkens, Yvonne F; van Meeteren, Nico L U
2012-01-01
The aim of this study was to investigate the relations between the ICF components from a subjective perspective. Data on health condition and perceived functioning were collected among 2941 individuals with at least one chronic disease or disorder. Path analysis was used with perceived level of participation as the final denominator. Three models were tested: one with the number of chronic diseases and disorders as an indicator of health condition, one with perceived health as indicator of health condition, and one with perceived health as part of the personal factors. Although all models showed a good fit, the model with the best fit was that with perceived health as an indicator of health condition. From a patient's perspective, components of the ICF scheme appear to be associated with each other, with perceived health being the best indicator of the health condition.
van Dokkum, Pieter G.; Conroy, Charlie
2012-11-01
The strength of gravity-sensitive absorption lines in the integrated light of old stellar populations is one of the few direct probes of the stellar initial mass function (IMF) outside of the Milky Way. Owing to the advent of fully depleted CCDs with little or no fringing it has recently become possible to obtain accurate measurements of these features. Here, we present spectra covering the wavelength ranges 0.35-0.55 μm and 0.72-1.03 μm for the bulge of M31 and 34 early-type galaxies from the SAURON sample, obtained with the Low Resolution Imaging Spectrometer on Keck. The signal-to-noise ratio is >~ 200 Å-1 out to 1 μm, which is sufficient to measure gravity-sensitive features for individual galaxies and to determine how they depend on other properties of the galaxies. Combining the new data with previously obtained spectra for globular clusters in M31 and the most massive elliptical galaxies in the Virgo cluster, we find that the dwarf-sensitive Na I λ8183, 8195 doublet and the FeH λ9916 Wing-Ford band increase systematically with velocity dispersion, while the giant-sensitive Ca II λ8498, 8542, 8662 triplet decreases with dispersion. These trends are consistent with a varying IMF, such that galaxies with deeper potential wells have more dwarf-enriched mass functions. In a companion paper, we use a comprehensive stellar population synthesis model to demonstrate that IMF effects can be separated from age and abundance variations and quantify the IMF variation among early-type galaxies.
International Nuclear Information System (INIS)
Van Dokkum, Pieter G.; Conroy, Charlie
2012-01-01
The strength of gravity-sensitive absorption lines in the integrated light of old stellar populations is one of the few direct probes of the stellar initial mass function (IMF) outside of the Milky Way. Owing to the advent of fully depleted CCDs with little or no fringing it has recently become possible to obtain accurate measurements of these features. Here, we present spectra covering the wavelength ranges 0.35-0.55 μm and 0.72-1.03 μm for the bulge of M31 and 34 early-type galaxies from the SAURON sample, obtained with the Low Resolution Imaging Spectrometer on Keck. The signal-to-noise ratio is ∼> 200 Å –1 out to 1 μm, which is sufficient to measure gravity-sensitive features for individual galaxies and to determine how they depend on other properties of the galaxies. Combining the new data with previously obtained spectra for globular clusters in M31 and the most massive elliptical galaxies in the Virgo cluster, we find that the dwarf-sensitive Na I λ8183, 8195 doublet and the FeH λ9916 Wing-Ford band increase systematically with velocity dispersion, while the giant-sensitive Ca II λ8498, 8542, 8662 triplet decreases with dispersion. These trends are consistent with a varying IMF, such that galaxies with deeper potential wells have more dwarf-enriched mass functions. In a companion paper, we use a comprehensive stellar population synthesis model to demonstrate that IMF effects can be separated from age and abundance variations and quantify the IMF variation among early-type galaxies.
Ocean Models and Proper Orthogonal Decomposition
Salas-de-Leon, D. A.
2007-05-01
The increasing computational developments and the better understanding of mathematical and physical systems resulted in an increasing number of ocean models. Long time ago, modelers were like a secret organization and recognize each other by using secret codes and languages that only a select group of people was able to recognize and understand. The access to computational systems was reduced, on one hand equipment and the using time of computers were expensive and restricted, and on the other hand, they required an advance computational languages that not everybody wanted to learn. Now a days most college freshman own a personal computer (PC or laptop), and/or have access to more sophisticated computational systems than those available for research in the early 80's. The resource availability resulted in a mayor access to all kind models. Today computer speed and time and the algorithms does not seem to be a problem, even though some models take days to run in small computational systems. Almost every oceanographic institution has their own model, what is more, in the same institution from one office to the next there are different models for the same phenomena, developed by different research member, the results does not differ substantially since the equations are the same, and the solving algorithms are similar. The algorithms and the grids, constructed with algorithms, can be found in text books and/or over the internet. Every year more sophisticated models are constructed. The Proper Orthogonal Decomposition is a technique that allows the reduction of the number of variables to solve keeping the model properties, for which it can be a very useful tool in diminishing the processes that have to be solved using "small" computational systems, making sophisticated models available for a greater community.
International Nuclear Information System (INIS)
Peggs, S.; Talman, R.
1986-08-01
As proton accelerators get larger, and include more magnets, the conventional tracking programs which simulate them run slower. At the same time, in order to more carefully optimize the higher cost of the accelerators, they must return more accurate results, even in the presence of a longer list of realistic effects, such as magnet errors and misalignments. For these reasons conventional tracking programs continue to be computationally bound, despite the continually increasing computing power available. This limitation is especially severe for a class of problems in which some lattice parameter is slowly varying, when a faithful description is only obtained by tracking for an exceedingly large number of turns. Examples are synchrotron oscillations in which the energy varies slowly with a period of, say, hundreds of turns, or magnet ripple or noise on a comparably slow time scale. In these cases one may with to track for hundreds of periods of the slowly varying parameter. The purpose of this paper is to describe a method, still under development, in which element-by-element tracking around one turn is replaced by a single map, which can be processed far faster. Similar programs have already been written in which successive elements are ''concatenated'' with truncation to linear, sextupole, or octupole order, et cetera, using Lie algebraic techniques to preserve symplecticity. The method described here is rather more empirical than this but, in principle, contains information to all orders and is able to handle resonances in a more straightforward fashion
Orthogonal polynomials on the unit circle part 2 spectral theory
Simon, Barry
2013-01-01
This two-part book is a comprehensive overview of the theory of probability measures on the unit circle, viewed especially in terms of the orthogonal polynomials defined by those measures. A major theme involves the connections between the Verblunsky coefficients (the coefficients of the recurrence equation for the orthogonal polynomials) and the measures, an analog of the spectral theory of one-dimensional Schrödinger operators. Among the topics discussed along the way are the asymptotics of Toeplitz determinants (Szegő's theorems), limit theorems for the density of the zeros of orthogonal po
Orthogonal polynomials on the unit circle part 1 classical theory
2009-01-01
This two-part book is a comprehensive overview of the theory of probability measures on the unit circle, viewed especially in terms of the orthogonal polynomials defined by those measures. A major theme involves the connections between the Verblunsky coefficients (the coefficients of the recurrence equation for the orthogonal polynomials) and the measures, an analog of the spectral theory of one-dimensional Schrodinger operators. Among the topics discussed along the way are the asymptotics of Toeplitz determinants (SzegÅ‘'s theorems), limit theorems for the density of the zeros of orthogonal po
Orthogonally Based Digital Content Management Applicable to Projects-bases
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Daniel MILODIN
2009-01-01
Full Text Available There is defined the concept of digital content. The requirements of an efficient management of the digital content are established. There are listed the quality characteristics of digital content. Orthogonality indicators of digital content are built up. They are meant to measure the image, the sound as well as the text orthogonality as well. Projects-base concept is introduced. There is presented the model of structuring the content in order to maximize orthogonality via a convergent iterative process. The model is instantiated for the digital content of a projects-base. It is introduced the application used to test the model. The paper ends with conclusions.
Directory of Open Access Journals (Sweden)
Zahra Sharafi
2017-01-01
Full Text Available Background. The purpose of this study was to evaluate the effectiveness of two methods of detecting differential item functioning (DIF in the presence of multilevel data and polytomously scored items. The assessment of DIF with multilevel data (e.g., patients nested within hospitals, hospitals nested within districts from large-scale assessment programs has received considerable attention but very few studies evaluated the effect of hierarchical structure of data on DIF detection for polytomously scored items. Methods. The ordinal logistic regression (OLR and hierarchical ordinal logistic regression (HOLR were utilized to assess DIF in simulated and real multilevel polytomous data. Six factors (DIF magnitude, grouping variable, intraclass correlation coefficient, number of clusters, number of participants per cluster, and item discrimination parameter with a fully crossed design were considered in the simulation study. Furthermore, data of Pediatric Quality of Life Inventory™ (PedsQL™ 4.0 collected from 576 healthy school children were analyzed. Results. Overall, results indicate that both methods performed equivalently in terms of controlling Type I error and detection power rates. Conclusions. The current study showed negligible difference between OLR and HOLR in detecting DIF with polytomously scored items in a hierarchical structure. Implications and considerations while analyzing real data were also discussed.
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M. V. Tchernycheva
2017-01-01
Full Text Available Subject of Research. The paper deals with development outcomes for creation method of one-electron wave functions of complex atoms, relatively simple, symmetrical for all atom electrons and free from hard computations. The accuracy and resource intensity of the approach are focused on systematic calculations of cross sections and rate constants of elementary processes of inelastic collisions of atoms or molecules with electrons (ionization, excitation, excitation transfer, and others. Method. The method is based on a set of two iterative processes. At the first iteration step the Schrödinger equation was solved numerically for the radial parts of the electron wave functions in the potential of the atomic core self-consistent field. At the second iteration step the new approximationfor the atomic core field is created that uses found solutions for all one-electron wave functions. The solution optimization for described multiparameter problem is achieved by the use of genetic algorithm. The suitability of the developed method was verified by comparing the calculation results with numerous data on the energies of atoms in the ground and excited states. Main Results. We have created the run-time version of the program for creation of sets of one-electron wave functions and calculation of the cross sections and constants of collisional transition rates in the first Born approximation. The priori available information about binding energies of the electrons for any many-particle system for creation of semi-empirical refined solutions for the one-electron wave functions can be considered at any step of this procedure. Practical Relevance. The proposed solution enables a simple and rapid preparation of input data for the numerical simulation of nonlocal gas discharge plasma. The approach is focused on the calculation of discharges in complex gas mixtures requiring inclusion in the model of a large number of elementary collisional and radiation
Systems of Differential Equations with Skew-Symmetric, Orthogonal Matrices
Glaister, P.
2008-01-01
The solution of a system of linear, inhomogeneous differential equations is discussed. The particular class considered is where the coefficient matrix is skew-symmetric and orthogonal, and where the forcing terms are sinusoidal. More general matrices are also considered.
Using orthogonal design to determine optimal conditions for ...
African Journals Online (AJOL)
African Journal of Biotechnology ... Because of the narrow genetic diversity of common wheat and elite agronomic traits of many wild relatives, it is very ... Key words: Protoplast, fusion, orthogonal design method, Mingxian 169, Y2155a.
Orthogonal Projector Kit (OPK) as a new teaching aids with ...
African Journals Online (AJOL)
... as a new teaching aids with innovation ICT in teaching and learning 21 st century. ... Mathematics education filled with abstract concepts, the use of teaching aids is ... This article aims to introduce and express the importance of Orthogonal ...
Rouquette, Alexandra; Badley, Elizabeth M; Falissard, Bruno; Dub, Timothée; Leplege, Alain; Coste, Joël
2015-06-01
The International Classification of Functioning, Disability and Health (ICF) published in 2001 describes the consequences of health conditions with three components of impairments in body structures or functions, activity limitations and participation restrictions. Two of the new features of the conceptual model were the possibility of feedback effects between each ICF component and the introduction of contextual factors conceptualized as moderators of the relationship between the components. The aim of this longitudinal study is to provide empirical evidence of these two kinds of effect. Structural equation modeling was used to analyze data from a French population-based cohort of 548 patients with knee osteoarthritis recruited between April 2007 and March 2009 and followed for three years. Indicators of the body structure and function, activity and participation components of the ICF were derived from self-administered standardized instruments. The measurement model revealed four separate factors for body structures impairments, body functions impairments, activity limitations and participation restrictions. The classic sequence from body impairments to participation restrictions through activity limitations was found at each assessment time. Longitudinal study of the ICF component relationships showed a feedback pathway indicating that the level of participation restrictions at baseline was predictive of activity limitations three years later. Finally, the moderating role of personal (age, sex, mental health, etc.) and environmental factors (family relationships, mobility device use, etc.) was investigated. Three contextual factors (sex, family relationships and walking stick use) were found to be moderators for the relationship between the body impairments and the activity limitations components. Mental health was found to be a mediating factor of the effect of activity limitations on participation restrictions. Copyright © 2015 Elsevier Ltd. All rights
Non-Orthogonal Opportunistic Beamforming: Performance Analysis and Implementation
Xia, Minghua
2012-04-01
Aiming to achieve the sum-rate capacity in multi-user multi-antenna systems where $N_t$ antennas are implemented at the transmitter, opportunistic beamforming (OBF) generates~$N_t$ orthonormal beams and serves $N_t$ users during each channel use, which results in high scheduling delay over the users, especially in densely populated networks. Non-orthogonal OBF with more than~$N_t$ transmit beams can be exploited to serve more users simultaneously and further decrease scheduling delay. However, the inter-beam interference will inevitably deteriorate the sum-rate. Therefore, there is a tradeoff between sum-rate and scheduling delay for non-orthogonal OBF. In this context, system performance and implementation of non-orthogonal OBF with $N>N_t$ beams are investigated in this paper. Specifically, it is analytically shown that non-orthogonal OBF is an interference-limited system as the number of users $K \\\\to \\\\infty$. When the inter-beam interference reaches its minimum for fixed $N_t$ and~$N$, the sum-rate scales as $N\\\\ln\\\\left(\\\\frac{N}{N-N_t}\\ ight)$ and it degrades monotonically with the number of beams $N$ for fixed $N_t$. On the contrary, the average scheduling delay is shown to scale as $\\\\frac{1}{N}K\\\\ln{K}$ channel uses and it improves monotonically with $N$. Furthermore, two practical non-orthogonal beamforming schemes are explicitly constructed and they are demonstrated to yield the minimum inter-beam interference for fixed $N_t$ and $N$. This study reveals that, if user traffic is light and one user can be successfully served within a single transmission, non-orthogonal OBF can be applied to obtain lower worst-case delay among the users. On the other hand, if user traffic is heavy, non-orthogonal OBF is inferior to orthogonal OBF in terms of sum-rate and packet delay.
Bounds and asymptotics for orthogonal polynomials for varying weights
Levin, Eli
2018-01-01
This book establishes bounds and asymptotics under almost minimal conditions on the varying weights, and applies them to universality limits and entropy integrals. Orthogonal polynomials associated with varying weights play a key role in analyzing random matrices and other topics. This book will be of use to a wide community of mathematicians, physicists, and statisticians dealing with techniques of potential theory, orthogonal polynomials, approximation theory, as well as random matrices. .
COMPUTER GRAPHICAL REPRESENTATION, IN TREBLE ORTHOGONAL PROJECTION, OF A POINT
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SLONOVSCHI Andrei
2017-05-01
Full Text Available In the stages of understanding and study, by students, of descriptive geometry, the treble orthogonal projection of a point, creates problems in the situations in that one or more descriptive coordinates are zero. Starting from these considerations the authors have created an original computer program which offers to the students the possibility to easily understanding of the way in which a point is represented, in draught, in the treble orthogonal projection whatever which are its values of the descriptive coordinates.
Genetic interaction studies are a powerful approach to identify functional interactions between genes. This approach can reveal networks of regulatory hubs and connect uncharacterized genes to well-studied pathways. However, this approach has previously been limited to simple gene inactivation studies. Here, we present an orthogonal CRISPR/Cas-mediated genetic interaction approach that allows the systematic activation of one gene while simultaneously knocking out a second gene in the same cell.
International Nuclear Information System (INIS)
Ginejtite, V.L.; Balyavichyus, L.Z.
1979-01-01
Some shortcomings of the semiempirical method CNDO/1 (complete naglect of differential overlap) taking into account wave function orthogonalities of outer valence electrons to inner shells are being explained. To avoid these shortcomings the introduction of pseudopotential is recommended. Addition of the potential excludes overestimation of attraction among chemically unbounded atoms, corrects underestimation of the single, double and triple S-S coupling, gives reasons for some suppositions of the semiempirical methods, gives a truthful distribution of the electronic levels
Non-Archimedean analogues of orthogonal and symmetric operators
International Nuclear Information System (INIS)
Albeverio, S; Bayod, J M; Perez-Garsia, C; Khrennikov, A Yu; Cianci, R
1999-01-01
We study orthogonal and symmetric operators on non-Archimedean Hilbert spaces in connection with the p-adic quantization. This quantization describes measurements with finite precision. Symmetric (bounded) operators on p-adic Hilbert spaces represent physical observables. We study the spectral properties of one of the most important quantum operators, namely, the position operator (which is represented on p-adic Hilbert L 2 -space with respect to the p-adic Gaussian measure). Orthogonal isometric isomorphisms of p-adic Hilbert spaces preserve the precision of measurements. We study properties of orthogonal operators. It is proved that every orthogonal operator on non-Archimedean Hilbert space is continuous. However, there are discontinuous operators with dense domain of definition that preserve the inner product. There exist non-isometric orthogonal operators. We describe some classes of orthogonal isometric operators on finite-dimensional spaces. We study some general questions in the theory of non-Archimedean Hilbert spaces (in particular, general connections between the topology, norm and inner product)
Jitter-Robust Orthogonal Hermite Pulses for Ultra-Wideband Impulse Radio Communications
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Ryuji Kohno
2005-03-01
Full Text Available The design of a class of jitter-robust, Hermite polynomial-based, orthogonal pulses for ultra-wideband impulse radio (UWB-IR communications systems is presented. A unified and exact closed-form expression of the auto- and cross-correlation functions of Hermite pulses is provided. Under the assumption that jitter values are sufficiently smaller than pulse widths, this formula is used to decompose jitter-shifted pulses over an orthonormal basis of the Hermite space. For any given jitter probability density function (pdf, the decomposition yields an equivalent distribution of N-by-N matrices which simplifies the convolutional jitter channel model onto a multiplicative matrix model. The design of jitter-robust orthogonal pulses is then transformed into a generalized eigendecomposition problem whose solution is obtained with a Jacobi-like simultaneous diagonalization algorithm applied over a subset of samples of the channel matrix distribution. Examples of the waveforms obtained with the proposed design and their improved auto- and cross-correlation functions are given. Simulation results are presented, which demonstrate the superior performance of a pulse-shape modulated (PSM- UWB-IR system using the proposed pulses, over the same system using conventional orthogonal Hermite pulses, in jitter channels with additive white Gaussian noise (AWGN.
PCT Uncertainty Analysis Using Unscented Transform with Random Orthogonal Matrix
Energy Technology Data Exchange (ETDEWEB)
Fynana, Douglas A.; Ahn, Kwang-Il [KAERI, Daejeon (Korea, Republic of); Lee, John C. [Univ. of Michigan, Michigan (United States)
2015-05-15
Most Best Estimate Plus Uncertainty (BEPU) methods employ nonparametric order statistics through Wilks' formula to quantify uncertainties of best estimate simulations of nuclear power plant (NPP) transients. 95%/95% limits, the 95''t{sup h} percentile at a 95% confidence level, are obtained by randomly sampling all uncertainty contributors through conventional Monte Carlo (MC). Advantages are simple implementation of MC sampling of input probability density functions (pdfs) and limited computational expense of 1''s{sup t}, 2''n{sup d}, and 3''r{sup d} order Wilks' formula requiring only 59, 93, or 124 simulations, respectively. A disadvantage of small sample size is large sample to sample variation of statistical estimators. This paper presents a new efficient sampling based algorithm for accurate estimation of mean and variance of the output parameter pdf. The algorithm combines a deterministic sampling method, the unscented transform (UT), with random sampling through the generation of a random orthogonal matrix (ROM). The UT guarantees the mean, covariance, and 3''r{sup d} order moments of the multivariate input parameter distributions are exactly preserved by the sampled input points and the orthogonal transformation of the points by a ROM guarantees the sample error of all 4''t{sup h} order and higher moments are unbiased. The UT with ROM algorithm is applied to the uncertainty quantification of the peak clad temperature (PCT) during a large break loss-of-coolant accident (LBLOCA) in an OPR1000 NPP to demonstrate the applicability of the new algorithm to BEPU. This paper presented a new algorithm combining the UT with ROM for efficient multivariate parameter sampling that ensures sample input covariance and 3''r{sup d} order moments are exactly preserved and 4''th moment errors are small and unbiased. The advantageous sample properties guarantee higher order accuracy and
Stochastic Ocean Predictions with Dynamically-Orthogonal Primitive Equations
Subramani, D. N.; Haley, P., Jr.; Lermusiaux, P. F. J.
2017-12-01
The coastal ocean is a prime example of multiscale nonlinear fluid dynamics. Ocean fields in such regions are complex and intermittent with unstationary heterogeneous statistics. Due to the limited measurements, there are multiple sources of uncertainties, including the initial conditions, boundary conditions, forcing, parameters, and even the model parameterizations and equations themselves. For efficient and rigorous quantification and prediction of these uncertainities, the stochastic Dynamically Orthogonal (DO) PDEs for a primitive equation ocean modeling system with a nonlinear free-surface are derived and numerical schemes for their space-time integration are obtained. Detailed numerical studies with idealized-to-realistic regional ocean dynamics are completed. These include consistency checks for the numerical schemes and comparisons with ensemble realizations. As an illustrative example, we simulate the 4-d multiscale uncertainty in the Middle Atlantic/New York Bight region during the months of Jan to Mar 2017. To provide intitial conditions for the uncertainty subspace, uncertainties in the region were objectively analyzed using historical data. The DO primitive equations were subsequently integrated in space and time. The probability distribution function (pdf) of the ocean fields is compared to in-situ, remote sensing, and opportunity data collected during the coincident POSYDON experiment. Results show that our probabilistic predictions had skill and are 3- to 4- orders of magnitude faster than classic ensemble schemes.
Aeroelastic System Development Using Proper Orthogonal Decomposition and Volterra Theory
Lucia, David J.; Beran, Philip S.; Silva, Walter A.
2003-01-01
This research combines Volterra theory and proper orthogonal decomposition (POD) into a hybrid methodology for reduced-order modeling of aeroelastic systems. The out-come of the method is a set of linear ordinary differential equations (ODEs) describing the modal amplitudes associated with both the structural modes and the POD basis functions for the uid. For this research, the structural modes are sine waves of varying frequency, and the Volterra-POD approach is applied to the fluid dynamics equations. The structural modes are treated as forcing terms which are impulsed as part of the uid model realization. Using this approach, structural and uid operators are coupled into a single aeroelastic operator. This coupling converts a free boundary uid problem into an initial value problem, while preserving the parameter (or parameters) of interest for sensitivity analysis. The approach is applied to an elastic panel in supersonic cross ow. The hybrid Volterra-POD approach provides a low-order uid model in state-space form. The linear uid model is tightly coupled with a nonlinear panel model using an implicit integration scheme. The resulting aeroelastic model provides correct limit-cycle oscillation prediction over a wide range of panel dynamic pressure values. Time integration of the reduced-order aeroelastic model is four orders of magnitude faster than the high-order solution procedure developed for this research using traditional uid and structural solvers.
Systematic Identification of MCU Modulators by Orthogonal Interspecies Chemical Screening.
Arduino, Daniela M; Wettmarshausen, Jennifer; Vais, Horia; Navas-Navarro, Paloma; Cheng, Yiming; Leimpek, Anja; Ma, Zhongming; Delrio-Lorenzo, Alba; Giordano, Andrea; Garcia-Perez, Cecilia; Médard, Guillaume; Kuster, Bernhard; García-Sancho, Javier; Mokranjac, Dejana; Foskett, J Kevin; Alonso, M Teresa; Perocchi, Fabiana
2017-08-17
The mitochondrial calcium uniporter complex is essential for calcium (Ca 2+ ) uptake into mitochondria of all mammalian tissues, where it regulates bioenergetics, cell death, and Ca 2+ signal transduction. Despite its involvement in several human diseases, we currently lack pharmacological agents for targeting uniporter activity. Here we introduce a high-throughput assay that selects for human MCU-specific small-molecule modulators in primary drug screens. Using isolated yeast mitochondria, reconstituted with human MCU, its essential regulator EMRE, and aequorin, and exploiting a D-lactate- and mannitol/sucrose-based bioenergetic shunt that greatly minimizes false-positive hits, we identify mitoxantrone out of more than 600 clinically approved drugs as a direct selective inhibitor of human MCU. We validate mitoxantrone in orthogonal mammalian cell-based assays, demonstrating that our screening approach is an effective and robust tool for MCU-specific drug discovery and, more generally, for the identification of compounds that target mitochondrial functions. Copyright © 2017 Elsevier Inc. All rights reserved.
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Kappeler Peter M
2011-04-01
Full Text Available Abstract Background Susceptibility to parasite infection affects fitness-related processes, such as mate choice and survival, yet its genetic regulation remains poorly understood. Interleukin-4 (IL4 plays a central role in the humoral immune defence against nematode parasite infections, inducing IgE switch and regulation of worm expulsion from the intestines. The evolutionary and functional significance of single nucleotide polymorphisms (SNPs in IL4-genes is known, yet empirical information on the effect of IL4 SNPs on gastro-intestinal infections is lacking. Using samples from a population of wild red-fronted lemurs (Eulemur fulvus rufus, Primates: Lemuridae, from western Madagascar, we explored the association of IL4-gene promoter polymorphisms with nematode infections and investigated a possible functional role of the IL4 polymorphism on male reproductive success. Results Using sequence analyses of lemur DNA we detected a new SNP in the IL4 gene promoter area. Carriers of the genotype T/T showed higher nematode infection intensities than individuals of genotypes C/T and C/C. Genetic population analyses using data from more than 10 years, suggested higher reproductive success of T/T males than expected. Conclusions Our results suggest a regulatory effect of an IL4 gene promoter polymorphism on the intensity of parasite infections in a natural population of red-fronted lemurs, with a seemingly disadvantageous genotype represented in low frequencies. Long-term population analyses, however, point in the direction of a negative frequency-dependent association, giving a fitness advantage to the rare genotype. Due to low frequencies of the genotype in question conclusive evidence of a functional role of IL4 polymorphism cannot be drawn here; still, we suggest the use of IL4 polymorphism as a new molecular tool for quick assessment of individual genetic constitution with regard to nematode infection intensities, contributing to a better
Functional Turnover: An Empirical Assessment.
1981-08-01
ci40L 0 4-J -)i c LA 4J 9- 0- to >- o 4 ’ L to0 00 0 w L L 4-) U0I l I . C 0) 0 -1, -4 co ) CD Ln ’ -. :3 LL0 0 L 41 4- 41 L I~ W- ire 0r_ M. 4C ...52-883 30 May 1981 LIST 7 HRM Officer in Charge Human Resource Management Detachment Naval Air Station Alameda, CA 94591 Officer in Charge Human
Li, Guoliang; Niu, Fenglin; Yang, Yingjie; Xie, Jun
2018-02-01
The time-frequency domain phase-weighted stacking (tf-PWS) technique based on the S transform has been employed in stacking empirical Green's functions (EGFs) derived from ambient noise data, mainly due to its superior power in enhancing weak signals. Questions such as the induced waveform distortion and the feasibility of phase-velocity extraction are yet to be thoroughly explored. In this study, we investigate these issues by conducting extensive numerical tests with both synthetic data and USArray transportable array (TA) ambient noise data. We find that the errors in the measured phase velocities associated with waveform distortion caused by the tf-PWS depend largely on the way of how the inverse S transform (IST) is implemented. If frequency IST is employed in tf-PWS, the corresponding errors are generally less than 0.1 per cent, sufficiently small that the measured phase velocities can be safely used in regular surface wave tomography. On the other hand, if a time IST is used in tf-PWS, then the extracted phase velocities are systematically larger than those measured from linearly stacked ones, and the discrepancy can reach as much as ˜0.4 per cent at some periods. Therefore, if tf-PWS is used in stacking EGFs, then frequency IST is preferred to transform the stacked S spectra back to the time domain for the stacked EGFs.
Energy Technology Data Exchange (ETDEWEB)
Fang, L. [LMP, Ecole Centrale de Pékin, Beihang University, Beijing 100191 (China); Co-Innovation Center for Advanced Aero-Engine, Beihang University, Beijing 100191 (China); Sun, X.Y. [LMP, Ecole Centrale de Pékin, Beihang University, Beijing 100191 (China); Liu, Y.W., E-mail: liuyangwei@126.com [National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics, School of Energy and Power Engineering, Beihang University, Beijing 100191 (China); Co-Innovation Center for Advanced Aero-Engine, Beihang University, Beijing 100191 (China)
2016-12-09
In order to shed light on understanding the subgrid-scale (SGS) modelling methodology, we analyze and define the concepts of assumption and restriction in the modelling procedure, then show by a generalized derivation that if there are multiple stationary restrictions in a modelling, the corresponding assumption function must satisfy a criterion of orthogonality. Numerical tests using one-dimensional nonlinear advection equation are performed to validate this criterion. This study is expected to inspire future research on generally guiding the SGS modelling methodology. - Highlights: • The concepts of assumption and restriction in the SGS modelling procedure are defined. • A criterion of orthogonality on the assumption and restrictions is derived. • Numerical tests using one-dimensional nonlinear advection equation are performed to validate this criterion.
Díaz Mendoza, C.; Orive, R.; Pijeira Cabrera, H.
2008-10-01
We study the asymptotic behavior of the zeros of a sequence of polynomials whose weighted norms, with respect to a sequence of weight functions, have the same nth root asymptotic behavior as the weighted norms of certain extremal polynomials. This result is applied to obtain the (contracted) weak zero distribution for orthogonal polynomials with respect to a Sobolev inner product with exponential weights of the form e-[phi](x), giving a unified treatment for the so-called Freud (i.e., when [phi] has polynomial growth at infinity) and Erdös (when [phi] grows faster than any polynomial at infinity) cases. In addition, we provide a new proof for the bound of the distance of the zeros to the convex hull of the support for these Sobolev orthogonal polynomials.
An orthogonality condition model treatment of elastic and inelastic (α, 12C) scattering
International Nuclear Information System (INIS)
Suzuki, Y.; Imanishi, B.
1981-02-01
Elastic and inelastic scattering of α-particles on the deformed nucleus 12 C are investigated in the range of incident α-particle energies of 9 to 11 MeV by using the coupled-channel method with orthogonality condition. A doubly folded potential generated by the shell model wave functions of the α-particle and the deformed nucleus 12 C is employed for the relative motion between the α-particle and 12 C. Good agreement between theory and experiment is obtained for the elastic and inelastic angular distributions and the resonance structures. It is found, from the Born series expansion of the T-matrix, that the orthogonality constraint stresses the effects of the channel-coupling between the elastic and inelastic processes, and it indicates that the DWBA does not work well in this system. (author)
Lu, Zhao; Sun, Jing; Butts, Kenneth
2014-05-01
Support vector regression for approximating nonlinear dynamic systems is more delicate than the approximation of indicator functions in support vector classification, particularly for systems that involve multitudes of time scales in their sampled data. The kernel used for support vector learning determines the class of functions from which a support vector machine can draw its solution, and the choice of kernel significantly influences the performance of a support vector machine. In this paper, to bridge the gap between wavelet multiresolution analysis and kernel learning, the closed-form orthogonal wavelet is exploited to construct new multiscale asymmetric orthogonal wavelet kernels for linear programming support vector learning. The closed-form multiscale orthogonal wavelet kernel provides a systematic framework to implement multiscale kernel learning via dyadic dilations and also enables us to represent complex nonlinear dynamics effectively. To demonstrate the superiority of the proposed multiscale wavelet kernel in identifying complex nonlinear dynamic systems, two case studies are presented that aim at building parallel models on benchmark datasets. The development of parallel models that address the long-term/mid-term prediction issue is more intricate and challenging than the identification of series-parallel models where only one-step ahead prediction is required. Simulation results illustrate the effectiveness of the proposed multiscale kernel learning.
International Nuclear Information System (INIS)
Paulinelli, H G; De Souza, S M; Rojas, Onofre
2013-01-01
In this paper we explore the entanglement in an orthogonal dimer-plaquette Ising–Heisenberg chain, assembled between plaquette edges, also known as orthogonal dimer plaquettes. The quantum entanglement properties involving an infinite chain structure are quite important, not only because the mathematical calculation is cumbersome but also because real materials are well represented by infinite chains. Using the local gauge symmetry of this model, we are able to map onto a simple spin-1 like Ising and spin-1/2 Heisenberg dimer model with single effective ion anisotropy. Thereafter this model can be solved using the decoration transformation and transfer matrix approach. First, we discuss the phase diagram at zero temperature of this model, where we find five ground states, one ferromagnetic, one antiferromagnetic, one triplet–triplet disordered and one triplet–singlet disordered phase, beside a dimer ferromagnetic–antiferromagnetic phase. In addition, we discuss the thermodynamic properties such as entropy, where we display the residual entropy. Furthermore, using the nearest site correlation function it is possible also to analyze the pairwise thermal entanglement for both orthogonal dimers. Additionally, we discuss the threshold temperature of the entangled region as a function of Hamiltonian parameters. We find a quite interesting thin reentrance threshold temperature for one of the dimers, and we also discuss the differences and similarities for both dimers. (paper)
Electrocardiogram ST-Segment Morphology Delineation Method Using Orthogonal Transformations.
Directory of Open Access Journals (Sweden)
Miha Amon
Full Text Available Differentiation between ischaemic and non-ischaemic transient ST segment events of long term ambulatory electrocardiograms is a persisting weakness in present ischaemia detection systems. Traditional ST segment level measuring is not a sufficiently precise technique due to the single point of measurement and severe noise which is often present. We developed a robust noise resistant orthogonal-transformation based delineation method, which allows tracing the shape of transient ST segment morphology changes from the entire ST segment in terms of diagnostic and morphologic feature-vector time series, and also allows further analysis. For these purposes, we developed a new Legendre Polynomials based Transformation (LPT of ST segment. Its basis functions have similar shapes to typical transient changes of ST segment morphology categories during myocardial ischaemia (level, slope and scooping, thus providing direct insight into the types of time domain morphology changes through the LPT feature-vector space. We also generated new Karhunen and Lo ève Transformation (KLT ST segment basis functions using a robust covariance matrix constructed from the ST segment pattern vectors derived from the Long Term ST Database (LTST DB. As for the delineation of significant transient ischaemic and non-ischaemic ST segment episodes, we present a study on the representation of transient ST segment morphology categories, and an evaluation study on the classification power of the KLT- and LPT-based feature vectors to classify between ischaemic and non-ischaemic ST segment episodes of the LTST DB. Classification accuracy using the KLT and LPT feature vectors was 90% and 82%, respectively, when using the k-Nearest Neighbors (k = 3 classifier and 10-fold cross-validation. New sets of feature-vector time series for both transformations were derived for the records of the LTST DB which is freely available on the PhysioNet website and were contributed to the LTST DB. The
Transferring strong boundedness among Laguerre orthogonal ...
Indian Academy of Sciences (India)
the multiplier operator associated with the sequence mk = k. √( k + α+1. 2. )( ... Theorem 2.9 (Multiplier theorem). Let −1 < α, 1 < p < ∞ and .... −αLα k (y2), where Lα k. (y) are the functions defined in (1.2). The functions ψα k are eigenfunctions for the operator Lα = −1. 4. { d2 dy2 +. (2α+1 y. ) d dy − y2}. , in effect. Lα(ψα k ) =.
Orthogonal expansions related to compact Gelfand pairs
DEFF Research Database (Denmark)
Berg, Christian; Peron, Ana P.; Porcu, Emilio
2017-01-01
. The functions of this class are the functions having a uniformly convergent expansion ∑ϕεZB(ϕ)(u)ϕ(x) for xεG,uεL, where the sum is over the space Z of positive definite spherical functions ϕ:G→C for the Gelfand pair, and (B(ϕ))ϕεZ is a family of continuous positive definite functions on L such that ∑ϕε......For a locally compact group G, let P(G) denote the set of continuous positive definite functions f:G→C. Given a compact Gelfand pair (G,K) and a locally compact group L, we characterize the class PK#(G,L) of functions fεP(G×L) which are bi-invariant in the G-variable with respect to K......(d)) and (U(q),U(q-1)) as well as for the product of these Gelfand pairs.The result generalizes recent theorems of Berg-Porcu (2016) and Guella-Menegatto (2016)....
Generalized Pseudospectral Method and Zeros of Orthogonal Polynomials
Directory of Open Access Journals (Sweden)
Oksana Bihun
2018-01-01
Full Text Available Via a generalization of the pseudospectral method for numerical solution of differential equations, a family of nonlinear algebraic identities satisfied by the zeros of a wide class of orthogonal polynomials is derived. The generalization is based on a modification of pseudospectral matrix representations of linear differential operators proposed in the paper, which allows these representations to depend on two, rather than one, sets of interpolation nodes. The identities hold for every polynomial family pνxν=0∞ orthogonal with respect to a measure supported on the real line that satisfies some standard assumptions, as long as the polynomials in the family satisfy differential equations Apν(x=qν(xpν(x, where A is a linear differential operator and each qν(x is a polynomial of degree at most n0∈N; n0 does not depend on ν. The proposed identities generalize known identities for classical and Krall orthogonal polynomials, to the case of the nonclassical orthogonal polynomials that belong to the class described above. The generalized pseudospectral representations of the differential operator A for the case of the Sonin-Markov orthogonal polynomials, also known as generalized Hermite polynomials, are presented. The general result is illustrated by new algebraic relations satisfied by the zeros of the Sonin-Markov polynomials.
Flow-orthogonal bead oscillation in a microfluidic chip with a magnetic anisotropic flux-guide array
DEFF Research Database (Denmark)
Van Pelt, Stijn; Derks, Roy; Matteucci, Marco
2011-01-01
A new concept for the manipulation of superparamagnetic beads inside a microfluidic chip is presented in this paper. The concept allows for bead actuation orthogonal to the flow direction inside a microchannel. Basic manipulation functionalities were studied by means of finite element simulations...
Theories for Elastic Plates via Orthogonal Polynomials
DEFF Research Database (Denmark)
Krenk, Steen
1981-01-01
A complementary energy functional is used to derive an infinite system of two-dimensional differential equations and appropriate boundary conditions for stresses and displacements in homogeneous anisotropic elastic plates. Stress boundary conditions are imposed on the faces a priori......, and this introduces a weight function in the variations of the transverse normal and shear stresses. As a result the coupling between the two-dimensional differential equations is described in terms of a single difference operator. Special attention is given to a truncated system of equations for bending...... of transversely isotropic plates. This theory has three boundary conditions, like Reissner's, but includes the effect of transverse normal strain, essentially through a reinterpretation of the transverse displacement function. Full agreement with general integrals to the homogeneous three-dimensional equations...
On some orthogonality properties of Maxwell's multipole vectors
International Nuclear Information System (INIS)
Gramada, Apostol
2007-01-01
We determine the location of the expansion points with respect to which the two Maxwell's multipole vectors of the quadrupole moment and the dipole vector of a distribution of charge form an orthogonal trihedron. We find that with respect to these 'orthogonality centres' both the dipole and the quadrupole moments are each characterized by a single real parameter. We further show that the orthogonality centres coincide with the stationary points of the magnitude of the quadrupole moment and, therefore, they can be seen as an extension of the concept of centre of the dipole moment of a neutral system introduced previously in the literature. The nature of the stationary points then provides the means for the classification of a distribution of charge in two different categories
Dral, Pavlo O; Wu, Xin; Spörkel, Lasse; Koslowski, Axel; Thiel, Walter
2016-03-08
The semiempirical orthogonalization-corrected OMx methods (OM1, OM2, and OM3) go beyond the standard MNDO model by including additional interactions in the electronic structure calculation. When augmented with empirical dispersion corrections, the resulting OMx-Dn approaches offer a fast and robust treatment of noncovalent interactions. Here we evaluate the performance of the OMx and OMx-Dn methods for a variety of ground-state properties using a large and diverse collection of benchmark sets from the literature, with a total of 13035 original and derived reference data. Extensive comparisons are made with the results from established semiempirical methods (MNDO, AM1, PM3, PM6, and PM7) that also use the NDDO (neglect of diatomic differential overlap) integral approximation. Statistical evaluations show that the OMx and OMx-Dn methods outperform the other methods for most of the benchmark sets.
Eising, Selma; Xin, Bo-Tao; Kleinpenning, Fleur; Heming, Juriaan; Florea, Bogdan; Overkleeft, Herman; Bonger, Kimberly Michelle
2018-05-28
Bioorthogonal chemistry can be used for the selective modification of biomolecules without interfering with any other functionality present. Recent developments in the field provided orthogonal bioorthogonal reactions for modification of multiple biomolecules simultaneously. During our research, we have observed exceptional high reaction rates in the bioorthogonal inverse electron-demand Diels-Alder (iEDDA) reaction between non-strained vinylboronic acids (VBAs) and dipyridyl-s-tetrazines relative to that of tetrazines bearing a methyl or phenyl substituent. As VBAs are mild Lewis acids, we hypothesize that coordination of the pyridyl nitrogen to the boronic acid promotes the tetrazine ligation. Here, we explore the molecular basis and scope of the VBA-tetrazine ligation in more detail and benefit from its unique reactivity in the simultaneous orthogonal tetrazine labelling of two proteins modified with VBA and norbornene, a widely used strained alkene. We further show that the two orthogonal iEDDA reactions can be carried out in living cells by labelling of the proteasome using a non-selective probe equipped with a VBA and a subunit-selective one bearing a norbornene. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Automorphisms of Algebras and Bochner's Property for Vector Orthogonal Polynomials
Horozov, Emil
2016-05-01
We construct new families of vector orthogonal polynomials that have the property to be eigenfunctions of some differential operator. They are extensions of the Hermite and Laguerre polynomial systems. A third family, whose first member has been found by Y. Ben Cheikh and K. Douak is also constructed. The ideas behind our approach lie in the studies of bispectral operators. We exploit automorphisms of associative algebras which transform elementary vector orthogonal polynomial systems which are eigenfunctions of a differential operator into other systems of this type.
Prediction of early summer rainfall over South China by a physical-empirical model
Yim, So-Young; Wang, Bin; Xing, Wen
2014-10-01
In early summer (May-June, MJ) the strongest rainfall belt of the northern hemisphere occurs over the East Asian (EA) subtropical front. During this period the South China (SC) rainfall reaches its annual peak and represents the maximum rainfall variability over EA. Hence we establish an SC rainfall index, which is the MJ mean precipitation averaged over 72 stations over SC (south of 28°N and east of 110°E) and represents superbly the leading empirical orthogonal function mode of MJ precipitation variability over EA. In order to predict SC rainfall, we established a physical-empirical model. Analysis of 34-year observations (1979-2012) reveals three physically consequential predictors. A plentiful SC rainfall is preceded in the previous winter by (a) a dipole sea surface temperature (SST) tendency in the Indo-Pacific warm pool, (b) a tripolar SST tendency in North Atlantic Ocean, and (c) a warming tendency in northern Asia. These precursors foreshadow enhanced Philippine Sea subtropical High and Okhotsk High in early summer, which are controlling factors for enhanced subtropical frontal rainfall. The physical empirical model built on these predictors achieves a cross-validated forecast correlation skill of 0.75 for 1979-2012. Surprisingly, this skill is substantially higher than four-dynamical models' ensemble prediction for 1979-2010 period (0.15). The results here suggest that the low prediction skill of current dynamical models is largely due to models' deficiency and the dynamical prediction has large room to improve.
Hung, Yu-Han; Tseng, Chin-Hao; Hwang, Sheng-Kwang
2018-06-01
This Letter investigates an optically injected semiconductor laser for conversion from non-orthogonally to orthogonally polarized optical single-sideband modulation. The underlying mechanism relies solely on nonlinear laser characteristics and, thus, only a typical semiconductor laser is required as the key conversion unit. This conversion can be achieved for a broadly tunable frequency range up to at least 65 GHz. After conversion, the microwave phase quality, including linewidth and phase noise, is mostly preserved, and simultaneous microwave amplification up to 23 dB is feasible.
Park, Joonam; Appiah, Williams Agyei; Byun, Seoungwoo; Jin, Dahee; Ryou, Myung-Hyun; Lee, Yong Min
2017-10-01
To overcome the limitation of simple empirical cycle life models based on only equivalent circuits, we attempt to couple a conventional empirical capacity loss model with Newman's porous composite electrode model, which contains both electrochemical reaction kinetics and material/charge balances. In addition, an electrolyte depletion function is newly introduced to simulate a sudden capacity drop at the end of cycling, which is frequently observed in real lithium-ion batteries (LIBs). When simulated electrochemical properties are compared with experimental data obtained with 20 Ah-level graphite/LiFePO4 LIB cells, our semi-empirical model is sufficiently accurate to predict a voltage profile having a low standard deviation of 0.0035 V, even at 5C. Additionally, our model can provide broad cycle life color maps under different c-rate and depth-of-discharge operating conditions. Thus, this semi-empirical model with an electrolyte depletion function will be a promising platform to predict long-term cycle lives of large-format LIB cells under various operating conditions.
Adaptive integrand decomposition in parallel and orthogonal space
International Nuclear Information System (INIS)
Mastrolia, Pierpaolo; Peraro, Tiziano; Primo, Amedeo
2016-01-01
We present the integrand decomposition of multiloop scattering amplitudes in parallel and orthogonal space-time dimensions, d=d ∥ +d ⊥ , being d ∥ the dimension of the parallel space spanned by the legs of the diagrams. When the number n of external legs is n≤4, the corresponding representation of multiloop integrals exposes a subset of integration variables which can be easily integrated away by means of Gegenbauer polynomials orthogonality condition. By decomposing the integration momenta along parallel and orthogonal directions, the polynomial division algorithm is drastically simplified. Moreover, the orthogonality conditions of Gegenbauer polynomials can be suitably applied to integrate the decomposed integrand, yielding the systematic annihilation of spurious terms. Consequently, multiloop amplitudes are expressed in terms of integrals corresponding to irreducible scalar products of loop momenta and external ones. We revisit the one-loop decomposition, which turns out to be controlled by the maximum-cut theorem in different dimensions, and we discuss the integrand reduction of two-loop planar and non-planar integrals up to n=8 legs, for arbitrary external and internal kinematics. The proposed algorithm extends to all orders in perturbation theory.
Orthogonal experimental study on high frequency cascade thermoacoustic engine
International Nuclear Information System (INIS)
Hu Zhongjun; Li Qing; Li Zhengyu; Li Qiang
2008-01-01
Orthogonal experiment design and variance analysis were adopted to investigate a miniature cascade thermoacoustic engine, which consisted of one standing wave stage and one traveling wave stage in series, operating at about 470 Hz, using helium as the working gas. Optimum matching of the heater powers between stages was very important for the performance of a cascade thermoacoustic engine, which was obtained from the orthogonal experiments. The orthogonal experiment design considered three experimental factors, i.e. the charging pressure and the heater powers in the two stages, which varied on five different levels, respectively. According to the range analysis and variance analysis from the orthogonal experiments, the charging pressure was the most sensitive factor influencing the dynamic pressure amplitude and onset temperature. The total efficiency and the dynamic pressure amplitude increased when the traveling wave stage heater power increased. The optimum ratio of the heater powers between the traveling wave stage and the standing wave stage was about 1.25, compromising the total efficiency with the dynamic pressure amplitude
Secrecy Capacity of a Class of Orthogonal Relay Eavesdropper Channels
Directory of Open Access Journals (Sweden)
Aggarwal Vaneet
2009-01-01
Full Text Available The secrecy capacity of relay channels with orthogonal components is studied in the presence of an additional passive eavesdropper node. The relay and destination receive signals from the source on two orthogonal channels such that the destination also receives transmissions from the relay on its channel. The eavesdropper can overhear either one or both of the orthogonal channels. Inner and outer bounds on the secrecy capacity are developed for both the discrete memoryless and the Gaussian channel models. For the discrete memoryless case, the secrecy capacity is shown to be achieved by a partial decode-and-forward (PDF scheme when the eavesdropper can overhear only one of the two orthogonal channels. Two new outer bounds are presented for the Gaussian model using recent capacity results for a Gaussian multiantenna point-to-point channel with a multiantenna eavesdropper. The outer bounds are shown to be tight for two subclasses of channels. The first subclass is one in which the source and relay are clustered, and the eavesdropper receives signals only on the channel from the source and the relay to the destination, for which the PDF strategy is optimal. The second is a subclass in which the source does not transmit to the relay, for which a noise-forwarding strategy is optimal.
Interactive 3D segmentation using connected orthogonal contours
de Bruin, P. W.; Dercksen, V. J.; Post, F. H.; Vossepoel, A. M.; Streekstra, G. J.; Vos, F. M.
2005-01-01
This paper describes a new method for interactive segmentation that is based on cross-sectional design and 3D modelling. The method represents a 3D model by a set of connected contours that are planar and orthogonal. Planar contours overlayed on image data are easily manipulated and linked contours
Adaptive integrand decomposition in parallel and orthogonal space
Energy Technology Data Exchange (ETDEWEB)
Mastrolia, Pierpaolo [Dipartimento di Fisica ed Astronomia, Università di Padova,Via Marzolo 8, 35131 Padova (Italy); INFN, Sezione di Padova,Via Marzolo 8, 35131 Padova (Italy); Peraro, Tiziano [Higgs Centre for Theoretical Physics, School of Physics and Astronomy,The University of Edinburgh,James Clerk Maxwell Building,Peter Guthrie Tait Road, Edinburgh EH9 3FD, Scotland (United Kingdom); Primo, Amedeo [Dipartimento di Fisica ed Astronomia, Università di Padova,Via Marzolo 8, 35131 Padova (Italy); INFN, Sezione di Padova,Via Marzolo 8, 35131 Padova (Italy)
2016-08-29
We present the integrand decomposition of multiloop scattering amplitudes in parallel and orthogonal space-time dimensions, d=d{sub ∥}+d{sub ⊥}, being d{sub ∥} the dimension of the parallel space spanned by the legs of the diagrams. When the number n of external legs is n≤4, the corresponding representation of multiloop integrals exposes a subset of integration variables which can be easily integrated away by means of Gegenbauer polynomials orthogonality condition. By decomposing the integration momenta along parallel and orthogonal directions, the polynomial division algorithm is drastically simplified. Moreover, the orthogonality conditions of Gegenbauer polynomials can be suitably applied to integrate the decomposed integrand, yielding the systematic annihilation of spurious terms. Consequently, multiloop amplitudes are expressed in terms of integrals corresponding to irreducible scalar products of loop momenta and external ones. We revisit the one-loop decomposition, which turns out to be controlled by the maximum-cut theorem in different dimensions, and we discuss the integrand reduction of two-loop planar and non-planar integrals up to n=8 legs, for arbitrary external and internal kinematics. The proposed algorithm extends to all orders in perturbation theory.
Dynamic imaging of skeletal muscle contraction in three orthogonal directions
Lopata, R.G.; van Dijk, J.P; Pillen, S.; Nillisen, M.M.; Maas, H.; Thijssen, J.M.; Stegeman, D.F.; Korte, C.L.
2010-01-01
In this study, a multidimensional strain estimation method using biplane ultrasound is presented to assess local relative deformation (i.e., local strain) in three orthogonal directions in skeletal muscles during induced and voluntary contractions. The method was tested in the musculus biceps
Dynamic imaging of skeletal muscle contraction in three orthogonal directions.
Lopata, R.G.P.; Dijk, J.P. van; Pillen, S.; Nillesen, M.M.; Maas, H.; Thijssen, J.M.; Stegeman, D.F.; Korte, C.L. de
2010-01-01
In this study, a multidimensional strain estimation method using biplane ultrasound is presented to assess local relative deformation (i.e., local strain) in three orthogonal directions in skeletal muscles during induced and voluntary contractions. The method was tested in the musculus biceps
Some p-ranks related to orthogonal spaces
Blokhuis, A.; Moorhouse, G.E.
1995-01-01
We determine the p-rank of the incidence matrix of hyperplanes of PG(n, p e) and points of a nondegenerate quadric. This yields new bounds for ovoids and the size of caps in finite orthogonal spaces. In particular, we show the nonexistence of ovoids in O10+ (2e ),O10+ (3e ),O9 (5e ),O12+ (5e
Short-Term Memory in Orthogonal Neural Networks
White, Olivia L.; Lee, Daniel D.; Sompolinsky, Haim
2004-04-01
We study the ability of linear recurrent networks obeying discrete time dynamics to store long temporal sequences that are retrievable from the instantaneous state of the network. We calculate this temporal memory capacity for both distributed shift register and random orthogonal connectivity matrices. We show that the memory capacity of these networks scales with system size.
Cospectral Graphs and Regular Orthogonal Matrices of Level 2
Abiad Monge, A.; Haemers, W.H.
2012-01-01
Abstract: For a graph Γ with adjacency matrix A, we consider a switching operation that takes Γ into a graph Γ' with adjacency matrix A', defined by A' = QtAQ, where Q is a regular orthogonal matrix of level 2 (that is, QtQ = I, Q1 = 1, 2Q is integral, and Q is not a permutation matrix). If such an
Application of Orthogonal Design to Optimize Extraction of ...
African Journals Online (AJOL)
Purpose: To optimize the extraction technology of polysaccharides from Cynomorium songaricum Rupr by ultrasonic-assisted extraction (UAE). Methods: Four parameters including ultrasonic power, ratio of raw material to water, extraction temperature, and extraction time were optimized by orthogonal design. The effects of ...
Non-orthogonally transitive G2 spike solution
International Nuclear Information System (INIS)
Lim, Woei Chet
2015-01-01
We generalize the orthogonally transitive (OT) G 2 spike solution to the non-OT G 2 case. This is achieved by applying Geroch’s transformation on a Kasner seed. The new solution contains two more parameters than the OT G 2 spike solution. Unlike the OT G 2 spike solution, the new solution always resolves its spike. (fast track communication)
Constructing General Orthogonal Fractional Factorial Split-Plot Designs
Sartono, B.; Goos, P.; Schoen, E.
2015-01-01
While the orthogonal design of split-plot fractional factorial experiments has received much attention already, there are still major voids in the literature. First, designs with one or more factors acting at more than two levels have not yet been considered. Second, published work on nonregular
Orthogonal designs Hadamard matrices, quadratic forms and algebras
Seberry, Jennifer
2017-01-01
Orthogonal designs have proved fundamental to constructing code division multiple antenna systems for more efficient mobile communications. Starting with basic theory, this book develops the algebra and combinatorics to create new communications modes. Intended primarily for researchers, it is also useful for graduate students wanting to understand some of the current communications coding theories.
Orthogonal feature selection method. [For preprocessing of man spectral data
Energy Technology Data Exchange (ETDEWEB)
Kowalski, B R [Univ. of Washington, Seattle; Bender, C F
1976-01-01
A new method of preprocessing spectral data for extraction of molecular structural information is desired. This SELECT method generates orthogonal features that are important for classification purposes and that also retain their identity to the original measurements. A brief introduction to chemical pattern recognition is presented. A brief description of the method and an application to mass spectral data analysis follow. (BLM)
A turbulent jet in crossflow analysed with proper orthogonal decomposition
DEFF Research Database (Denmark)
Meyer, Knud Erik; Pedersen, Jakob Martin; Özcan, Oktay
2007-01-01
and pipe diameter was 2400 and the jet to crossflow velocity ratios were R = 3.3 and R = 1.3. The experimental data have been analysed by proper orthogonal decomposition (POD). For R = 3.3, the results in several different planes indicate that the wake vortices are the dominant dynamic flow structures...
Differentiation by integration using orthogonal polynomials, a survey
Diekema, E.; Koornwinder, T.H.
2012-01-01
This survey paper discusses the history of approximation formulas for n-th order derivatives by integrals involving orthogonal polynomials. There is a large but rather disconnected corpus of literature on such formulas. We give some results in greater generality than in the literature. Notably we
Sparsely-Packetized Predictive Control by Orthogonal Matching Pursuit
DEFF Research Database (Denmark)
Nagahara, Masaaki; Quevedo, Daniel; Østergaard, Jan
2012-01-01
We study packetized predictive control, known to be robust against packet dropouts in networked systems. To obtain sparse packets for rate-limited networks, we design control packets via an ℓ0 optimization, which can be eectively solved by orthogonal matching pursuit. Our formulation ensures...
Short-term memory in orthogonal neural networks
International Nuclear Information System (INIS)
White, Olivia L.; Lee, Daniel D.; Sompolinsky, Haim
2004-01-01
We study the ability of linear recurrent networks obeying discrete time dynamics to store long temporal sequences that are retrievable from the instantaneous state of the network. We calculate this temporal memory capacity for both distributed shift register and random orthogonal connectivity matrices. We show that the memory capacity of these networks scales with system size
Velocity field calculation for non-orthogonal numerical grids
Energy Technology Data Exchange (ETDEWEB)
Flach, G. P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)
2015-03-01
Computational grids containing cell faces that do not align with an orthogonal (e.g. Cartesian, cylindrical) coordinate system are routinely encountered in porous-medium numerical simulations. Such grids are referred to in this study as non-orthogonal grids because some cell faces are not orthogonal to a coordinate system plane (e.g. xy, yz or xz plane in Cartesian coordinates). Non-orthogonal grids are routinely encountered at the Savannah River Site in porous-medium flow simulations for Performance Assessments and groundwater flow modeling. Examples include grid lines that conform to the sloping roof of a waste tank or disposal unit in a 2D Performance Assessment simulation, and grid surfaces that conform to undulating stratigraphic surfaces in a 3D groundwater flow model. Particle tracking is routinely performed after a porous-medium numerical flow simulation to better understand the dynamics of the flow field and/or as an approximate indication of the trajectory and timing of advective solute transport. Particle tracks are computed by integrating the velocity field from cell to cell starting from designated seed (starting) positions. An accurate velocity field is required to attain accurate particle tracks. However, many numerical simulation codes report only the volumetric flowrate (e.g. PORFLOW) and/or flux (flowrate divided by area) crossing cell faces. For an orthogonal grid, the normal flux at a cell face is a component of the Darcy velocity vector in the coordinate system, and the pore velocity for particle tracking is attained by dividing by water content. For a non-orthogonal grid, the flux normal to a cell face that lies outside a coordinate plane is not a true component of velocity with respect to the coordinate system. Nonetheless, normal fluxes are often taken as Darcy velocity components, either naively or with accepted approximation. To enable accurate particle tracking or otherwise present an accurate depiction of the velocity field for a non-orthogonal
Dujardin, Alain; Causse, Mathieu; Courboulex, Françoise; Traversa, Paola
2016-06-01
The two main earthquakes that occurred in 2012 (May 20 and 29) in the Reggio-Emiliano region (Northern Italy) were relatively small (Mw 6.1 and Mw 5.9) but they generated unexpected damages in a large area around the epicenter. On some stations, the observed seismic levels exceeded design levels recommended by the EC8 seismic code for buildings and civil engineering works. The ground motions generated by the two mainshocks have specific characteristics: the waveforms are mainly controlled by surface waves generated by the deep sedimentary Po plain, by local site effects and also, on some stations, by non-linear behaviors. In this particular context, we test the ability of an empirical Green's function (EGF) simulation approach to reproduce the recorded seismograms in a large frequency band without any knowledge of the underground medium. We focus on the possibility to reproduce the strong surface waves generated by the basin at distances between 25 and 90 km. We choose to work on the second mainshock of the sequence (Mw 5.9), which occurred on May 29, 2012, because it is better recorded by the seismological networks than the May 20th first mainshock. We use a k-2 kinematic source model to generate a set of 100 slip distributions on the fault plane and choose the recordings of a close-by Mw 3.9 event as EGF. We then generate a set of broad-band seismograms (from 0.2 to 35 Hz) and compare them to the mainshock signals at 15 stations (Seismograms, Fourier spectra, PGA, PGV, duration, Stockwell Transforms) at epicentral distances from 5 to 160 km. We find that the main specific features of the signals are very well reproduced for all the stations within and beyond the basin. Nevertheless, at nearby stations, the PGA values are over-evaluated, which could be explained by the fact that non- linear effects are not taken into account in the simulation process. A better fit was found for a position of the nucleation point to the bottom west of the fault, that suggest a
Del Gaudio, Sergio; Hok, Sebastien; Festa, Gaetano; Causse, Mathieu; Lancieri, Maria
2017-09-01
Seismic hazard estimation relies classically on data-based ground motion prediction equations (GMPEs) giving the expected motion level as a function of several parameters characterizing the source and the sites of interest. However, records of moderate to large earthquakes at short distances from the faults are still rare. For this reason, it is difficult to obtain a reliable ground motion prediction for such a class of events and distances where also the largest amount of damage is usually observed. A possible strategy to fill this lack of information is to generate synthetic accelerograms based on an accurate modeling of both extended fault rupture and wave propagation process. The development of such modeling strategies is essential for estimating seismic hazard close to faults in moderate seismic activity zones, where data are even scarcer. For that reason, we selected a target site in Upper Rhine Graben (URG), at the French-German border. URG is a region where faults producing micro-seismic activity are very close to the sites of interest (e.g., critical infrastructures like supply lines, nuclear power plants, etc.) needing a careful investigation of seismic hazard. In this work, we demonstrate the feasibility of performing near-fault broadband ground motion numerical simulations in a moderate seismic activity region such as URG and discuss some of the challenges related to such an application. The modeling strategy is to couple the multi-empirical Green's function technique (multi-EGFt) with a k -2 kinematic source model. One of the advantages of the multi-EGFt is that it does not require a detailed knowledge of the propagation medium since the records of small events are used as the medium transfer function, if, at the target site, records of small earthquakes located on the target fault are available. The selection of suitable events to be used as multi-EGF is detailed and discussed in our specific situation where less number of events are available. We
Sparrow, P.; Farndale, E.; Scullion, H.
2013-01-01
This study presents an empirical exploration of a theory-driven framework of corporate human resource (CHR) roles in global talent management (GTM). Specifically, it expands our knowledge of the process of GTM in two sectors: financial and professional services. Based on in-depth interview data from
Cluster transfer form factor and intercluster relative motion in the orthogonality-condition model
International Nuclear Information System (INIS)
Lovas, R.G.; Pal, K.F.
1984-01-01
The orthogonality-condition model (OCM), as an approximation method for calculating the overlap and potential overlap functions involved in the form factor of transfer reactions, is tested against microscopic cluster calculations for the 7 Li=α+t system. The OCM overlap and potential overlap turned out to depend strongly on the OCM potential although the potentials are chosen so as to produce the same asymptotic phase. Excellent approximations to microscopic overlaps and potential overlaps are, however, obtained by optimizing the OCM potential so that the OCM may reproduce the microscopic energy surface. This way the dependence on the OCM potential is traced back to the underlying nucleon-nucleon force. (author)
On the method of orthogonal projections in the theory of elasticity
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Valerii V. Struzhanov
2017-07-01
Full Text Available The method of orthogonal projections applied to the task of determining the stresses in the elastic deformable bodies, which allowed us to relax the requirements to the smoothness of the functions defining external forces and to the components of the tensor of the initial strains, which cause the appearance of balanced self-stresses. Examples of the calculation of quench stresses in a circular cylinder and residual stresses after shrinkage of the binder in composite cylinders made by winding are given.
P A M Dirac meets M G Krein: matrix orthogonal polynomials and Dirac's equation
Energy Technology Data Exchange (ETDEWEB)
Duran, Antonio J [Departamento de Analisis Matematico, Universidad de Sevilla, Apdo (PO BOX) 1160, 41080 Sevilla (Spain); Gruenbaum, F Alberto [Department of Mathematics, University of California, Berkeley, CA 94720 (United States)
2006-04-07
The solution of several instances of the Schroedinger equation (1926) is made possible by using the well-known orthogonal polynomials associated with the names of Hermite, Legendre and Laguerre. A relativistic alternative to this equation was proposed by Dirac (1928) involving differential operators with matrix coefficients. In 1949 Krein developed a theory of matrix-valued orthogonal polynomials without any reference to differential equations. In Duran A J (1997 Matrix inner product having a matrix symmetric second order differential operator Rocky Mt. J. Math. 27 585-600), one of us raised the question of determining instances of these matrix-valued polynomials going along with second order differential operators with matrix coefficients. In Duran A J and Gruenbaum F A (2004 Orthogonal matrix polynomials satisfying second order differential equations Int. Math. Res. Not. 10 461-84), we developed a method to produce such examples and observed that in certain cases there is a connection with the instance of Dirac's equation with a central potential. We observe that the case of the central Coulomb potential discussed in the physics literature in Darwin C G (1928 Proc. R. Soc. A 118 654), Nikiforov A F and Uvarov V B (1988 Special Functions of Mathematical Physics (Basle: Birkhauser) and Rose M E 1961 Relativistic Electron Theory (New York: Wiley)), and its solution, gives rise to a matrix weight function whose orthogonal polynomials solve a second order differential equation. To the best of our knowledge this is the first instance of a connection between the solution of the first order matrix equation of Dirac and the theory of matrix-valued orthogonal polynomials initiated by M G Krein.
Orthogonal Analysis Based Performance Optimization for Vertical Axis Wind Turbine
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Lei Song
2016-01-01
Full Text Available Geometrical shape of a vertical axis wind turbine (VAWT is composed of multiple structural parameters. Since there are interactions among the structural parameters, traditional research approaches, which usually focus on one parameter at a time, cannot obtain performance of the wind turbine accurately. In order to exploit overall effect of a novel VAWT, we firstly use a single parameter optimization method to obtain optimal values of the structural parameters, respectively, by Computational Fluid Dynamics (CFD method; based on the results, we then use an orthogonal analysis method to investigate the influence of interactions of the structural parameters on performance of the wind turbine and to obtain optimization combination of the structural parameters considering the interactions. Results of analysis of variance indicate that interactions among the structural parameters have influence on performance of the wind turbine, and optimization results based on orthogonal analysis have higher wind energy utilization than that of traditional research approaches.
Tomographic Approach in Three-Orthogonal-Basis Quantum Key Distribution
International Nuclear Information System (INIS)
Liang Wen-Ye; Yin Zhen-Qiang; Chen Hua; Li Hong-Wei; Chen Wei; Han Zheng-Fu; Wen Hao
2015-01-01
At present, there is an increasing awareness of some three-orthogonal-basis quantum key distribution protocols, such as, the reference-frame-independent (RFI) protocol and the six-state protocol. For secure key rate estimations of these protocols, there are two methods: one is the conventional approach, and another is the tomographic approach. However, a comparison between these two methods has not been given yet. In this work, with the general model of rotation channel, we estimate the key rate using conventional and tomographic methods respectively. Results show that conventional estimation approach in RFI protocol is equivalent to tomographic approach only in the case of that one of three orthogonal bases is always aligned. In other cases, tomographic approach performs much better than the respective conventional approaches of the RFI protocol and the six-state protocol. Furthermore, based on the experimental data, we illustrate the deep connections between tomography and conventional RFI approach representations. (paper)
Quantum secret sharing using orthogonal multiqudit entangled states
Bai, Chen-Ming; Li, Zhi-Hui; Liu, Cheng-Ji; Li, Yong-Ming
2017-12-01
In this work, we investigate the distinguishability of orthogonal multiqudit entangled states under restricted local operations and classical communication. According to these properties, we propose a quantum secret sharing scheme to realize three types of access structures, i.e., the ( n, n)-threshold, the restricted (3, n)-threshold and restricted (4, n)-threshold schemes (called LOCC-QSS scheme). All cooperating players in the restricted threshold schemes are from two disjoint groups. In the proposed protocol, the participants use the computational basis measurement and classical communication to distinguish between those orthogonal states and reconstruct the original secret. Furthermore, we also analyze the security of our scheme in four primary quantum attacks and give a simple encoding method in order to better prevent the participant conspiracy attack.
Force Modelling in Orthogonal Cutting Considering Flank Wear Effect
Rathod, Kanti Bhikhubhai; Lalwani, Devdas I.
2017-05-01
In the present work, an attempt has been made to provide a predictive cutting force model during orthogonal cutting by combining two different force models, that is, a force model for a perfectly sharp tool plus considering the effect of edge radius and a force model for a worn tool. The first force model is for a perfectly sharp tool that is based on Oxley's predictive machining theory for orthogonal cutting as the Oxley's model is for perfectly sharp tool, the effect of cutting edge radius (hone radius) is added and improve model is presented. The second force model is based on worn tool (flank wear) that was proposed by Waldorf. Further, the developed combined force model is also used to predict flank wear width using inverse approach. The performance of the developed combined total force model is compared with the previously published results for AISI 1045 and AISI 4142 materials and found reasonably good agreement.
A General Approach for Orthogonal 4-Tap Integer Multiwavelet Transforms
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Mingli Jing
2010-01-01
Full Text Available An algorithm for orthogonal 4-tap integer multiwavelet transforms is proposed. We compute the singular value decomposition (SVD of block recursive matrices of transform matrix, and then transform matrix can be rewritten in a product of two block diagonal matrices and a permutation matrix. Furthermore, we factorize the block matrix of block diagonal matrices into triangular elementary reversible matrices (TERMs, which map integers to integers by rounding arithmetic. The cost of factorizing block matrix into TERMs does not increase with the increase of the dimension of transform matrix, and the proposed algorithm is in-place calculation and without allocating auxiliary memory. Examples of integer multiwavelet transform using DGHM and CL are given, which verify that the proposed algorithm is an executable algorithm and outperforms the existing algorithm for orthogonal 4-tap integer multiwavelet transform.
Radar Measurements of Ocean Surface Waves using Proper Orthogonal Decomposition
2017-03-30
Golinval, 2002, Physical interpretation of the proper orthogonal modes using the singular value decomposition, Journal of Sound and Vibration, 249...complex and contain contributions from the environment (e.g., wind, waves, currents) as well as artifacts associated with electromagnetic (EM) (wave...Although there is no physical basis/ interpretation inherent to the method because it is purely a mathematical tool, there has been an increasing
TEACHING BASIC ELEMENTS IN TECHNICAL DRAWING – ORTHOGONAL PROJECTIONS
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CLINCIU Ramona
2017-05-01
Full Text Available The paper presents applications developed using AutoCAD and 3D Studio MAX programs. These applications are constructed such as to enable, gradually, the development of the spatial abilities of the students and, at the same time, to enable the understanding of the principles for the representation of the orthogonal projections of the parts, as well as for the construction of their axonometric projections.
Orthogonal frequency division multiple access fundamentals and applications
Jiang, Tao; Zhang, Yan
2010-01-01
Supported by the expert-level advice of pioneering researchers, Orthogonal Frequency Division Multiple Access Fundamentals and Applications provides a comprehensive and accessible introduction to the foundations and applications of one of the most promising access technologies for current and future wireless networks. It includes authoritative coverage of the history, fundamental principles, key techniques, and critical design issues of OFDM systems. Covering various techniques of effective resource management for OFDM/OFDMA-based wireless communication systems, this cutting-edge reference:Add
Cospectral graphs and regular orthogonal matrices of level 2
Abiad Monge, A.; Haemers, W.H.
2012-01-01
For a graph Γ with adjacency matrix A , we consider a switching operation that takes Γ into a graph Γ′ with adjacency matrix A′ , defined by A′ = Q⊤AQ , where Q is a regular orthogonal matrix of level 2 (that is, Q⊤Q=I , Q1 = 1, 2Q is integral, and Q is not a permutation matrix). If such an
Discrete Orthogonal Transforms and Neural Networks for Image Interpolation
Directory of Open Access Journals (Sweden)
J. Polec
1999-09-01
Full Text Available In this contribution we present transform and neural network approaches to the interpolation of images. From transform point of view, the principles from [1] are modified for 1st and 2nd order interpolation. We present several new interpolation discrete orthogonal transforms. From neural network point of view, we present interpolation possibilities of multilayer perceptrons. We use various configurations of neural networks for 1st and 2nd order interpolation. The results are compared by means of tables.
A general boundary capability embedded in an orthogonal mesh
International Nuclear Information System (INIS)
Hewett, D.W.; Yu-Jiuan Chen
1995-01-01
The authors describe how they hold onto orthogonal mesh discretization when dealing with curved boundaries. Special difference operators were constructed to approximate numerical zones split by the domain boundary; the operators are particularly simple for this rectangular mesh. The authors demonstrated that this simple numerical approach, termed Dynamic Alternating Direction Implicit, turned out to be considerably more efficient than more complex grid-adaptive algorithms that were tried previously
Minimal parameter solution of the orthogonal matrix differential equation
Bar-Itzhack, Itzhack Y.; Markley, F. Landis
1990-01-01
As demonstrated in this work, all orthogonal matrices solve a first order differential equation. The straightforward solution of this equation requires n sup 2 integrations to obtain the element of the nth order matrix. There are, however, only n(n-1)/2 independent parameters which determine an orthogonal matrix. The questions of choosing them, finding their differential equation and expressing the orthogonal matrix in terms of these parameters are considered. Several possibilities which are based on attitude determination in three dimensions are examined. It is shown that not all 3-D methods have useful extensions to higher dimensions. It is also shown why the rate of change of the matrix elements, which are the elements of the angular rate vector in 3-D, are the elements of a tensor of the second rank (dyadic) in spaces other than three dimensional. It is proven that the 3-D Gibbs vector (or Cayley Parameters) are extendable to other dimensions. An algorithm is developed emplying the resulting parameters, which are termed Extended Rodrigues Parameters, and numerical results are presented of the application of the algorithm to a fourth order matrix.
Efficiency Improvements of Antenna Optimization Using Orthogonal Fractional Experiments
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Yen-Sheng Chen
2015-01-01
Full Text Available This paper presents an extremely efficient method for antenna design and optimization. Traditionally, antenna optimization relies on nature-inspired heuristic algorithms, which are time-consuming due to their blind-search nature. In contrast, design of experiments (DOE uses a completely different framework from heuristic algorithms, reducing the design cycle by formulating the surrogates of a design problem. However, the number of required simulations grows exponentially if a full factorial design is used. In this paper, a much more efficient technique is presented to achieve substantial time savings. By using orthogonal fractional experiments, only a small subset of the full factorial design is required, yet the resultant response surface models are still effective. The capability of orthogonal fractional experiments is demonstrated through three examples, including two tag antennas for radio-frequency identification (RFID applications and one internal antenna for long-term-evolution (LTE handheld devices. In these examples, orthogonal fractional experiments greatly improve the efficiency of DOE, thereby facilitating the antenna design with less simulation runs.
Limited-memory adaptive snapshot selection for proper orthogonal decomposition
Energy Technology Data Exchange (ETDEWEB)
Oxberry, Geoffrey M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kostova-Vassilevska, Tanya [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Arrighi, Bill [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Chand, Kyle [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
2015-04-02
Reduced order models are useful for accelerating simulations in many-query contexts, such as optimization, uncertainty quantification, and sensitivity analysis. However, offline training of reduced order models can have prohibitively expensive memory and floating-point operation costs in high-performance computing applications, where memory per core is limited. To overcome this limitation for proper orthogonal decomposition, we propose a novel adaptive selection method for snapshots in time that limits offline training costs by selecting snapshots according an error control mechanism similar to that found in adaptive time-stepping ordinary differential equation solvers. The error estimator used in this work is related to theory bounding the approximation error in time of proper orthogonal decomposition-based reduced order models, and memory usage is minimized by computing the singular value decomposition using a single-pass incremental algorithm. Results for a viscous Burgers’ test problem demonstrate convergence in the limit as the algorithm error tolerances go to zero; in this limit, the full order model is recovered to within discretization error. The resulting method can be used on supercomputers to generate proper orthogonal decomposition-based reduced order models, or as a subroutine within hyperreduction algorithms that require taking snapshots in time, or within greedy algorithms for sampling parameter space.
MRI isotropic resolution reconstruction from two orthogonal scans
Tamez-Pena, Jose G.; Totterman, Saara; Parker, Kevin J.
2001-07-01
An algorithm for the reconstructions of ISO-resolution volumetric MR data sets from two standard orthogonal MR scans having anisotropic resolution has been developed. The reconstruction algorithm starts by registering a pair of orthogonal volumetric MR data sets. The registration is done by maximizing the correlation between the gradient magnitude using a simple translation-rotation model in a multi-resolution approach. Then algorithm assumes that the individual voxels on the MR data are an average of the magnetic resonance properties of an elongated imaging volume. Then, the process is modeled as the projection of MR properties into a single sensor. This model allows the derivation of a set of linear equations that can be used to recover the MR properties of every single voxel in the SO-resolution volume given only two orthogonal MR scans. Projections on convex sets (POCS) was used to solve the set of linear equations. Experimental results show the advantage of having a ISO-resolution reconstructions for the visualization and analysis of small and thin muscular structures.
Parallel and orthogonal stimulus in ultradiluted neural networks
International Nuclear Information System (INIS)
Sobral, G. A. Jr.; Vieira, V. M.; Lyra, M. L.; Silva, C. R. da
2006-01-01
Extending a model due to Derrida, Gardner, and Zippelius, we have studied the recognition ability of an extreme and asymmetrically diluted version of the Hopfield model for associative memory by including the effect of a stimulus in the dynamics of the system. We obtain exact results for the dynamic evolution of the average network superposition. The stimulus field was considered as proportional to the overlapping of the state of the system with a particular stimulated pattern. Two situations were analyzed, namely, the external stimulus acting on the initialization pattern (parallel stimulus) and the external stimulus acting on a pattern orthogonal to the initialization one (orthogonal stimulus). In both cases, we obtained the complete phase diagram in the parameter space composed of the stimulus field, thermal noise, and network capacity. Our results show that the system improves its recognition ability for parallel stimulus. For orthogonal stimulus two recognition phases emerge with the system locking at the initialization or stimulated pattern. We confront our analytical results with numerical simulations for the noiseless case T=0
Cosine and sine operators related to orthogonal polynomial sets on the interval [-1, 1
International Nuclear Information System (INIS)
Appl, Thomas; Schiller, Diethard H
2005-01-01
The quantization of phase is still an open problem. In the approach of Susskind and Glogower, the so-called cosine and sine operators play a fundamental role. Their eigenstates in the Fock representation are related to the Chebyshev polynomials of the second kind. Here we introduce more general cosine and sine operators whose eigenfunctions in the Fock basis are related in a similar way to arbitrary orthogonal polynomial sets on the interval [-1, 1]. To each polynomial set defined in terms of a weight function there corresponds a pair of cosine and sine operators. Depending on the symmetry of the weight function, we distinguish generalized or extended operators. Their eigenstates are used to define cosine and sine representations and probability distributions. We also consider the arccosine and arcsine operators and use their eigenstates to define cosine-phase and sine-phase distributions, respectively. Specific, numerical and graphical results are given for the classical orthogonal polynomials and for particular Fock and coherent states
Fsheikh, Ahmed H.
2013-01-01
A nonlinear orthogonal matching pursuit (NOMP) for sparse calibration of reservoir models is presented. Sparse calibration is a challenging problem as the unknowns are both the non-zero components of the solution and their associated weights. NOMP is a greedy algorithm that discovers at each iteration the most correlated components of the basis functions with the residual. The discovered basis (aka support) is augmented across the nonlinear iterations. Once the basis functions are selected from the dictionary, the solution is obtained by applying Tikhonov regularization. The proposed algorithm relies on approximate gradient estimation using an iterative stochastic ensemble method (ISEM). ISEM utilizes an ensemble of directional derivatives to efficiently approximate gradients. In the current study, the search space is parameterized using an overcomplete dictionary of basis functions built using the K-SVD algorithm.
Orthogonal Clickable Iron Oxide Nanoparticle Platform for Targeting, Imaging, and On-Demand Release.
Guldris, Noelia; Gallo, Juan; García-Hevia, Lorena; Rivas, José; Bañobre-López, Manuel; Salonen, Laura M
2018-04-12
A versatile iron oxide nanoparticle platform is reported that can be orthogonally functionalized to obtain highly derivatized nanomaterials required for a wide variety of applications, such as drug delivery, targeted therapy, or imaging. Facile functionalization of the nanoparticles with two ligands containing isocyanate moieties allows for high coverage of the surface with maleimide and alkyne groups. As a proof-of-principle, the nanoparticles were subsequently functionalized with a fluorophore as a drug model and with biotin as a targeting ligand towards tumor cells through Diels-Alder and azide-alkyne cycloaddition reactions, respectively. The thermoreversibility of the Diels-Alder product was exploited to induce the on-demand release of the loaded molecules by magnetic hyperthermia. Additionally, the nanoparticles were shown to target cancer cells through in vitro experiments, as analyzed by magnetic resonance imaging. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Gao, Ning; Tian, Tian; Cui, Jiecheng; Zhang, Wanlin; Yin, Xianpeng; Wang, Shiqiang; Ji, Jingwei; Li, Guangtao
2017-03-27
A microfluidic assembly approach was developed for efficiently producing hydrogel spheres with reactive multidomains that can be employed as an advantageous platform to create spherical porous networks in a facile manner with well-defined multicompartments and spatiotemporally controlled functions. This strategy allows for not only large scale fabrication of various robust hydrogel microspheres with controlled size and porosity, but also the domains embedded in hydrogel network could be introduced in a modular manner. Additionally, the number of different domains and their ratio could be widely variable on demand. More importantly, the reactive groups distributed in individual domains could be used as anchor sites to further incorporate functional units in an orthogonal fashion, leading to well-defined multicompartment systems. The strategy provides a new and efficient route to construct well-defined functional multicompartment systems with great flexibility and extendibility. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Perlin, Pesach; Gharakhanian, Eric G; Deming, Timothy J
2018-06-12
Homoallylglycine N-carboxyanhydride, Hag NCA, monomers were synthesized and used to prepare polypeptides containing Hag segments with controllable lengths of up to 245 repeats. Poly(l-homoallylglycine), GHA, was found to adopt an α-helical conformation, which provided good solubility in organic solvents and allowed high yield functionalization of its alkene side-chains via radical promoted addition of thiols. The conformations of these derivatives were shown to be switchable between α-helical and disordered states in aqueous media using thioether alkylation or oxidation reactions. Incorporation of GHA segments into block copolymers with poly(l-methionine), M, segments provided a means to orthogonally modify thioether side-chains different ways in separate copolypeptide domains. This approach allows preparation of functional polypeptides containing discrete domains of oxidized and alkylated thioether containing residues, where chain conformation and functionality of each domain can be independently modified.
Empirical Test Case Specification
DEFF Research Database (Denmark)
Kalyanova, Olena; Heiselberg, Per
This document includes the empirical specification on the IEA task of evaluation building energy simulation computer programs for the Double Skin Facades (DSF) constructions. There are two approaches involved into this procedure, one is the comparative approach and another is the empirical one. I....... In the comparative approach the outcomes of different software tools are compared, while in the empirical approach the modelling results are compared with the results of experimental test cases....
Bio-Orthogonal Mediated Nucleic Acid Transfection of Cells via Cell Surface Engineering.
O'Brien, Paul J; Elahipanah, Sina; Rogozhnikov, Dmitry; Yousaf, Muhammad N
2017-05-24
The efficient delivery of foreign nucleic acids (transfection) into cells is a critical tool for fundamental biomedical research and a pillar of several biotechnology industries. There are currently three main strategies for transfection including reagent, instrument, and viral based methods. Each technology has significantly advanced cell transfection; however, reagent based methods have captured the majority of the transfection market due to their relatively low cost and ease of use. This general method relies on the efficient packaging of a reagent with nucleic acids to form a stable complex that is subsequently associated and delivered to cells via nonspecific electrostatic targeting. Reagent transfection methods generally use various polyamine cationic type molecules to condense with negatively charged nucleic acids into a highly positively charged complex, which is subsequently delivered to negatively charged cells in culture for association, internalization, release, and expression. Although this appears to be a straightforward procedure, there are several major issues including toxicity, low efficiency, sorting of viable transfected from nontransfected cells, and limited scope of transfectable cell types. Herein, we report a new strategy (SnapFect) for nucleic acid transfection to cells that does not rely on electrostatic interactions but instead uses an integrated approach combining bio-orthogonal liposome fusion, click chemistry, and cell surface engineering. We show that a target cell population is rapidly and efficiently engineered to present a bio-orthogonal functional group on its cell surface through nanoparticle liposome delivery and fusion. A complementary bio-orthogonal nucleic acid complex is then formed and delivered to which chemoselective click chemistry induced transfection occurs to the primed cell. This new strategy requires minimal time, steps, and reagents and leads to superior transfection results for a broad range of cell types
Adaptive PID control based on orthogonal endocrine neural networks.
Milovanović, Miroslav B; Antić, Dragan S; Milojković, Marko T; Nikolić, Saša S; Perić, Staniša Lj; Spasić, Miodrag D
2016-12-01
A new intelligent hybrid structure used for online tuning of a PID controller is proposed in this paper. The structure is based on two adaptive neural networks, both with built-in Chebyshev orthogonal polynomials. First substructure network is a regular orthogonal neural network with implemented artificial endocrine factor (OENN), in the form of environmental stimuli, to its weights. It is used for approximation of control signals and for processing system deviation/disturbance signals which are introduced in the form of environmental stimuli. The output values of OENN are used to calculate artificial environmental stimuli (AES), which represent required adaptation measure of a second network-orthogonal endocrine adaptive neuro-fuzzy inference system (OEANFIS). OEANFIS is used to process control, output and error signals of a system and to generate adjustable values of proportional, derivative, and integral parameters, used for online tuning of a PID controller. The developed structure is experimentally tested on a laboratory model of the 3D crane system in terms of analysing tracking performances and deviation signals (error signals) of a payload. OENN-OEANFIS performances are compared with traditional PID and 6 intelligent PID type controllers. Tracking performance comparisons (in transient and steady-state period) showed that the proposed adaptive controller possesses performances within the range of other tested controllers. The main contribution of OENN-OEANFIS structure is significant minimization of deviation signals (17%-79%) compared to other controllers. It is recommended to exploit it when dealing with a highly nonlinear system which operates in the presence of undesirable disturbances. Copyright © 2016 Elsevier Ltd. All rights reserved.
The endoscopic classification of representations orthogonal and symplectic groups
Arthur, James
2013-01-01
Within the Langlands program, endoscopy is a fundamental process for relating automorphic representations of one group with those of another. In this book, Arthur establishes an endoscopic classification of automorphic representations of orthogonal and symplectic groups G. The representations are shown to occur in families (known as global L-packets and A-packets), which are parametrized by certain self-dual automorphic representations of an associated general linear group GL(N). The central result is a simple and explicit formula for the multiplicity in the automorphic discrete spectrum of G
Cavity enhanced interference of orthogonal modes in a birefringent medium
Kolluru, Kiran; Saha, Sudipta; Gupta, S. Dutta
2018-03-01
Interference of orthogonal modes in a birefringent crystal mediated by a rotator is known to lead to interesting physical effects (Solli et al., 2003). In this paper we show that additional feedback offered by a Fabry-Perot cavity (containing the birefringent crystal and the rotator) can lead to a novel strong interaction regime. Usual signatures of the strong interaction regime like the normal mode splitting and avoided crossings, sensitive to the rotator orientation, are reported. A high finesse cavity is shown to offer an optical setup for measuring small angles. The results are based on direct calculations of the cavity transmissions along with an analysis of its dispersion relation.
ORIENTATION FIELD RECONSTRUCTION OF ALTERED FINGERPRINT USING ORTHOGONAL WAVELETS
Directory of Open Access Journals (Sweden)
Mini M.G.
2016-11-01
Full Text Available Ridge orientation field is an important feature for fingerprint matching and fingerprint reconstruction. Matching of the altered fingerprint against its unaltered mates can be done by extracting the available features in the altered fingerprint and using it along with approximated ridge orientation. This paper presents a method for approximating ridge orientation field of altered fingerprints. In the proposed method, sine and cosine of doubled orientation of the fingerprint is decomposed using orthogonal wavelets and reconstructed back using only the approximation coefficients. No prior information about the singular points is needed for orientation approximation. The method is found suitable for orientation estimation of low quality fingerprint images also.
Introduction to orthogonal, symplectic and unitary representations of finite groups
Riehm, Carl R
2011-01-01
Orthogonal, symplectic and unitary representations of finite groups lie at the crossroads of two more traditional subjects of mathematics-linear representations of finite groups, and the theory of quadratic, skew symmetric and Hermitian forms-and thus inherit some of the characteristics of both. This book is written as an introduction to the subject and not as an encyclopaedic reference text. The principal goal is an exposition of the known results on the equivalence theory, and related matters such as the Witt and Witt-Grothendieck groups, over the "classical" fields-algebraically closed, rea
Orthogonal polarization in lasers physical phenomena and engineering applications
Zhang, Shulian
2013-01-01
This practical book summarizes the latest research results of orthogonally polarized lasers, birefringence laser cavities, and their applications. Coverage ranges from basic principles and technologies to the characteristics of different cavities and lasers to various measurement techniques. A number of figures, experimental designs, and measurement curves are included, helping readers gain a thorough understanding of the many applications in modern engineering and start their own projects. Many types of relevant lasers (Helium/Neon lasers, Nd:YAG lasers, laser diodes, etc.) are also discussed
Neural Based Orthogonal Data Fitting The EXIN Neural Networks
Cirrincione, Giansalvo
2008-01-01
Written by three leaders in the field of neural based algorithms, Neural Based Orthogonal Data Fitting proposes several neural networks, all endowed with a complete theory which not only explains their behavior, but also compares them with the existing neural and traditional algorithms. The algorithms are studied from different points of view, including: as a differential geometry problem, as a dynamic problem, as a stochastic problem, and as a numerical problem. All algorithms have also been analyzed on real time problems (large dimensional data matrices) and have shown accurate solutions. Wh
Directed Formation of DNA Nanoarrays through Orthogonal Self-Assembly
Directory of Open Access Journals (Sweden)
Eugen Stulz
2011-06-01
Full Text Available We describe the synthesis of terpyridine modified DNA strands which selectively form DNA nanotubes through orthogonal hydrogen bonding and metal complexation interactions. The short DNA strands are designed to self-assemble into long duplexes through a sticky-end approach. Addition of weakly binding metals such as Zn(II and Ni(II induces the formation of tubular arrays consisting of DNA bundles which are 50-200 nm wide and 2-50 nm high. TEM shows additional long distance ordering of the terpy-DNA complexes into fibers.
Magnitude conversion to unified moment magnitude using orthogonal regression relation
Das, Ranjit; Wason, H. R.; Sharma, M. L.
2012-05-01
Homogenization of earthquake catalog being a pre-requisite for seismic hazard assessment requires region based magnitude conversion relationships. Linear Standard Regression (SR) relations fail when both the magnitudes have measurement errors. To accomplish homogenization, techniques like Orthogonal Standard Regression (OSR) are thus used. In this paper a technique is proposed for using such OSR for preparation of homogenized earthquake catalog in moment magnitude Mw. For derivation of orthogonal regression relation between mb and Mw, a data set consisting of 171 events with observed body wave magnitudes (mb,obs) and moment magnitude (Mw,obs) values has been taken from ISC and GCMT databases for Northeast India and adjoining region for the period 1978-2006. Firstly, an OSR relation given below has been developed using mb,obs and Mw,obs values corresponding to 150 events from this data set. M=1.3(±0.004)m-1.4(±0.130), where mb,proxy are body wave magnitude values of the points on the OSR line given by the orthogonality criterion, for observed (mb,obs, Mw,obs) points. A linear relation is then developed between these 150 mb,obs values and corresponding mb,proxy values given by the OSR line using orthogonality criterion. The relation obtained is m=0.878(±0.03)m+0.653(±0.15). The accuracy of the above procedure has been checked with the rest of the data i.e., 21 events values. The improvement in the correlation coefficient value between mb,obs and Mw estimated using the proposed procedure compared to the correlation coefficient value between mb,obs and Mw,obs shows the advantage of OSR relationship for homogenization. The OSR procedure developed in this study can be used to homogenize any catalog containing various magnitudes (e.g., ML, mb, MS) with measurement errors, by their conversion to unified moment magnitude Mw. The proposed procedure also remains valid in case the magnitudes have measurement errors of different orders, i.e. the error variance ratio is
Orthogonal Bases used for Feed Forward Control of Wind Turbines
DEFF Research Database (Denmark)
Odgaard, Peter Fogh; Stoustrup, Jakob
2011-01-01
In optimizing wind turbines it can be of a large help to use information of wind speeds at upwind turbine for the control of downwind turbines, it is, however, problematic to use these measurements directly since they are highly inﬂuenced by turbulence behind the wind turbine rotor plane. In this....... In this paper an orthogonal basis is use to extract the general trends in the wind signal, which are forward to the down wind turbines. This concept controller is designed and simulated on a generic 4.8 MW wind turbine model, which shows the potential of this proposed scheme....
Magnetic particle detection in unshielded environment using orthogonal fluxgate gradiometer
Energy Technology Data Exchange (ETDEWEB)
Elrefai, Ahmed L., E-mail: a.lotfyelrefai@gmail.com; Sasada, Ichiro [Applied Science for Electronics and Materials, Kyushu University, Kasuga (Japan)
2015-05-07
A new detection system for magnetic particles, which can operate in an unshielded environment, is developed using a fundamental mode orthogonal fluxgate gradiometer. The proposed detection system offers the advantages of cost, size, and weight reduction as compared to contamination detection systems using superconducting quantum interference device sensor. The detection system can be used to detect metallic contamination in foods or lithium ion battery production lines. The system has been investigated numerically to optimize various design parameters of the system. Experimental setup has been developed to evaluate some of the numerically predicted results. Steel balls were successfully detected down to the diameter of 50 μm.
Nucleic acid constructs containing orthogonal site selective recombinases (OSSRs)
Energy Technology Data Exchange (ETDEWEB)
Gilmore, Joshua M.; Anderson, J. Christopher; Dueber, John E.
2017-08-29
The present invention provides for a recombinant nucleic acid comprising a nucleotide sequence comprising a plurality of constructs, wherein each construct independently comprises a nucleotide sequence of interest flanked by a pair of recombinase recognition sequences. Each pair of recombinase recognition sequences is recognized by a distinct recombinase. Optionally, each construct can, independently, further comprise one or more genes encoding a recombinase capable of recognizing the pair of recombinase recognition sequences of the construct. The recombinase can be an orthogonal (non-cross reacting), site-selective recombinase (OSSR).
Computation of the Likelihood in Biallelic Diffusion Models Using Orthogonal Polynomials
Directory of Open Access Journals (Sweden)
Claus Vogl
2014-11-01
Full Text Available In population genetics, parameters describing forces such as mutation, migration and drift are generally inferred from molecular data. Lately, approximate methods based on simulations and summary statistics have been widely applied for such inference, even though these methods waste information. In contrast, probabilistic methods of inference can be shown to be optimal, if their assumptions are met. In genomic regions where recombination rates are high relative to mutation rates, polymorphic nucleotide sites can be assumed to evolve independently from each other. The distribution of allele frequencies at a large number of such sites has been called “allele-frequency spectrum” or “site-frequency spectrum” (SFS. Conditional on the allelic proportions, the likelihoods of such data can be modeled as binomial. A simple model representing the evolution of allelic proportions is the biallelic mutation-drift or mutation-directional selection-drift diffusion model. With series of orthogonal polynomials, specifically Jacobi and Gegenbauer polynomials, or the related spheroidal wave function, the diffusion equations can be solved efficiently. In the neutral case, the product of the binomial likelihoods with the sum of such polynomials leads to finite series of polynomials, i.e., relatively simple equations, from which the exact likelihoods can be calculated. In this article, the use of orthogonal polynomials for inferring population genetic parameters is investigated.
Canonical Structure and Orthogonality of Forces and Currents in Irreversible Markov Chains
Kaiser, Marcus; Jack, Robert L.; Zimmer, Johannes
2018-03-01
We discuss a canonical structure that provides a unifying description of dynamical large deviations for irreversible finite state Markov chains (continuous time), Onsager theory, and Macroscopic Fluctuation Theory (MFT). For Markov chains, this theory involves a non-linear relation between probability currents and their conjugate forces. Within this framework, we show how the forces can be split into two components, which are orthogonal to each other, in a generalised sense. This splitting allows a decomposition of the pathwise rate function into three terms, which have physical interpretations in terms of dissipation and convergence to equilibrium. Similar decompositions hold for rate functions at level 2 and level 2.5. These results clarify how bounds on entropy production and fluctuation theorems emerge from the underlying dynamical rules. We discuss how these results for Markov chains are related to similar structures within MFT, which describes hydrodynamic limits of such microscopic models.
Empirical Philosophy of Science
DEFF Research Database (Denmark)
Mansnerus, Erika; Wagenknecht, Susann
2015-01-01
knowledge takes place through the integration of the empirical or historical research into the philosophical studies, as Chang, Nersessian, Thagard and Schickore argue in their work. Building upon their contributions we will develop a blueprint for an Empirical Philosophy of Science that draws upon...... qualitative methods from the social sciences in order to advance our philosophical understanding of science in practice. We will regard the relationship between philosophical conceptualization and empirical data as an iterative dialogue between theory and data, which is guided by a particular ‘feeling with......Empirical insights are proven fruitful for the advancement of Philosophy of Science, but the integration of philosophical concepts and empirical data poses considerable methodological challenges. Debates in Integrated History and Philosophy of Science suggest that the advancement of philosophical...
Huang, Shijie; Zhu, Xuechen; Melançon, Charles E
2016-01-15
The ribosome is the quintessential antibacterial drug target, with many structurally and mechanistically distinct classes of antibacterial agents acting by inhibiting ribosome function. Detecting and quantifying ribosome inhibition by small molecules and investigating their binding modes and mechanisms of action are critical to antibacterial drug discovery and development efforts. To develop a ribosome inhibition assay that is operationally simple, yet provides direct information on the drug target and the mechanism of action, we have developed engineered E. coli strains harboring an orthogonal ribosome-controlled green fluorescent protein (GFP) reporter that produce fluorescent signal when the orthogonal ribosome is inhibited. As a proof of concept, we demonstrate that these strains, when coexpressing homogeneous populations of aminoglycoside resistant ribosomes, act as sensitive and quantitative detectors of ribosome inhibition by a set of 12 structurally diverse aminoglycoside antibiotics. We suggest that this strategy can be extended to quantifying ribosome inhibition by other drug classes.
Bifurcations in two-image photometric stereo for orthogonal illuminations
Kozera, R.; Prokopenya, A.; Noakes, L.; Śluzek, A.
2017-07-01
This paper discusses the ambiguous shape recovery in two-image photometric stereo for a Lambertian surface. The current uniqueness analysis refers to linearly independent light-source directions p = (0, 0, -1) and q arbitrary. For this case necessary and sufficient condition determining ambiguous reconstruction is governed by a second-order linear partial differential equation with constant coefficients. In contrast, a general position of both non-colinear illumination directions p and q leads to a highly non-linear PDE which raises a number of technical difficulties. As recently shown, the latter can also be handled for another family of orthogonal illuminations parallel to the OXZ-plane. For the special case of p = (0, 0, -1) a potential ambiguity stems also from the possible bifurcations of sub-local solutions glued together along a curve defined by an algebraic equation in terms of the data. This paper discusses the occurrence of similar bifurcations for such configurations of orthogonal light-source directions. The discussion to follow is supplemented with examples based on continuous reflectance map model and generated synthetic images.
Statistical benchmarking for orthogonal electrostatic quantum dot qubit devices
Gamble, John; Frees, Adam; Friesen, Mark; Coppersmith, S. N.
2014-03-01
Quantum dots in semiconductor systems have emerged as attractive candidates for the implementation of quantum information processors because of the promise of scalability, manipulability, and integration with existing classical electronics. A limitation in current devices is that the electrostatic gates used for qubit manipulation exhibit strong cross-capacitance, presenting a barrier for practical scale-up. Here, we introduce a statistical framework for making precise the notion of orthogonality. We apply our method to analyze recently implemented designs at the University of Wisconsin-Madison that exhibit much increased orthogonal control than was previously possible. We then use our statistical modeling to future device designs, providing practical guidelines for devices to have robust control properties. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy Nuclear Security Administration under contract DE-AC04-94AL85000. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either expressly or implied, of the US Government. This work was supported in part by the Laboratory Directed Research and Development program at Sandia National Laboratories, by ARO (W911NF-12-0607), and by the United States Department of Defense.
Downlink Non-Orthogonal Multiple Access (NOMA) in Poisson Networks
Ali, Konpal S.
2018-03-21
A network model is considered where Poisson distributed base stations transmit to $N$ power-domain non-orthogonal multiple access (NOMA) users (UEs) each that employ successive interference cancellation (SIC) for decoding. We propose three models for the clustering of NOMA UEs and consider two different ordering techniques for the NOMA UEs: mean signal power-based and instantaneous signal-to-intercell-interference-and-noise-ratio-based. For each technique, we present a signal-to-interference-and-noise ratio analysis for the coverage of the typical UE. We plot the rate region for the two-user case and show that neither ordering technique is consistently superior to the other. We propose two efficient algorithms for finding a feasible resource allocation that maximize the cell sum rate $\\\\mathcal{R}_{\\ m tot}$, for general $N$, constrained to: 1) a minimum rate $\\\\mathcal{T}$ for each UE, 2) identical rates for all UEs. We show the existence of: 1) an optimum $N$ that maximizes the constrained $\\\\mathcal{R}_{\\ m tot}$ given a set of network parameters, 2) a critical SIC level necessary for NOMA to outperform orthogonal multiple access. The results highlight the importance in choosing the network parameters $N$, the constraints, and the ordering technique to balance the $\\\\mathcal{R}_{\\ m tot}$ and fairness requirements. We also show that interference-aware UE clustering can significantly improve performance.
Power system frequency estimation based on an orthogonal decomposition method
Lee, Chih-Hung; Tsai, Men-Shen
2018-06-01
In recent years, several frequency estimation techniques have been proposed by which to estimate the frequency variations in power systems. In order to properly identify power quality issues under asynchronously-sampled signals that are contaminated with noise, flicker, and harmonic and inter-harmonic components, a good frequency estimator that is able to estimate the frequency as well as the rate of frequency changes precisely is needed. However, accurately estimating the fundamental frequency becomes a very difficult task without a priori information about the sampling frequency. In this paper, a better frequency evaluation scheme for power systems is proposed. This method employs a reconstruction technique in combination with orthogonal filters, which may maintain the required frequency characteristics of the orthogonal filters and improve the overall efficiency of power system monitoring through two-stage sliding discrete Fourier transforms. The results showed that this method can accurately estimate the power system frequency under different conditions, including asynchronously sampled signals contaminated by noise, flicker, and harmonic and inter-harmonic components. The proposed approach also provides high computational efficiency.
Cerenkov luminescence tomography based on preconditioning orthogonal matching pursuit
Liu, Haixiao; Hu, Zhenhua; Wang, Kun; Tian, Jie; Yang, Xin
2015-03-01
Cerenkov luminescence imaging (CLI) is a novel optical imaging method and has been proved to be a potential substitute of the traditional radionuclide imaging such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT). This imaging method inherits the high sensitivity of nuclear medicine and low cost of optical molecular imaging. To obtain the depth information of the radioactive isotope, Cerenkov luminescence tomography (CLT) is established and the 3D distribution of the isotope is reconstructed. However, because of the strong absorption and scatter, the reconstruction of the CLT sources is always converted to an ill-posed linear system which is hard to be solved. In this work, the sparse nature of the light source was taken into account and the preconditioning orthogonal matching pursuit (POMP) method was established to effectively reduce the ill-posedness and obtain better reconstruction accuracy. To prove the accuracy and speed of this algorithm, a heterogeneous numerical phantom experiment and an in vivo mouse experiment were conducted. Both the simulation result and the mouse experiment showed that our reconstruction method can provide more accurate reconstruction result compared with the traditional Tikhonov regularization method and the ordinary orthogonal matching pursuit (OMP) method. Our reconstruction method will provide technical support for the biological application for Cerenkov luminescence.
Non-Orthogonal Multiple Access for Ubiquitous Wireless Sensor Networks.
Anwar, Asim; Seet, Boon-Chong; Ding, Zhiguo
2018-02-08
Ubiquitous wireless sensor networks (UWSNs) have become a critical technology for enabling smart cities and other ubiquitous monitoring applications. Their deployment, however, can be seriously hampered by the spectrum available to the sheer number of sensors for communication. To support the communication needs of UWSNs without requiring more spectrum resources, the power-domain non-orthogonal multiple access (NOMA) technique originally proposed for 5th Generation (5G) cellular networks is investigated for UWSNs for the first time in this paper. However, unlike 5G networks that operate in the licensed spectrum, UWSNs mostly operate in unlicensed spectrum where sensors also experience cross-technology interferences from other devices sharing the same spectrum. In this paper, we model the interferences from various sources at the sensors using stochastic geometry framework. To evaluate the performance, we derive a theorem and present new closed form expression for the outage probability of the sensors in a downlink scenario under interference limited environment. In addition, diversity analysis for the ordered NOMA users is performed. Based on the derived outage probability, we evaluate the average link throughput and energy consumption efficiency of NOMA against conventional orthogonal multiple access (OMA) technique in UWSNs. Further, the required computational complexity for the NOMA users is presented.
Downlink Non-Orthogonal Multiple Access (NOMA) in Poisson Networks
Ali, Konpal S.; Haenggi, Martin; Elsawy, Hesham; Chaaban, Anas; Alouini, Mohamed-Slim
2018-01-01
A network model is considered where Poisson distributed base stations transmit to $N$ power-domain non-orthogonal multiple access (NOMA) users (UEs) each that employ successive interference cancellation (SIC) for decoding. We propose three models for the clustering of NOMA UEs and consider two different ordering techniques for the NOMA UEs: mean signal power-based and instantaneous signal-to-intercell-interference-and-noise-ratio-based. For each technique, we present a signal-to-interference-and-noise ratio analysis for the coverage of the typical UE. We plot the rate region for the two-user case and show that neither ordering technique is consistently superior to the other. We propose two efficient algorithms for finding a feasible resource allocation that maximize the cell sum rate $\\mathcal{R}_{\\rm tot}$, for general $N$, constrained to: 1) a minimum rate $\\mathcal{T}$ for each UE, 2) identical rates for all UEs. We show the existence of: 1) an optimum $N$ that maximizes the constrained $\\mathcal{R}_{\\rm tot}$ given a set of network parameters, 2) a critical SIC level necessary for NOMA to outperform orthogonal multiple access. The results highlight the importance in choosing the network parameters $N$, the constraints, and the ordering technique to balance the $\\mathcal{R}_{\\rm tot}$ and fairness requirements. We also show that interference-aware UE clustering can significantly improve performance.
Modeling of Particle Emission During Dry Orthogonal Cutting
Khettabi, Riad; Songmene, Victor; Zaghbani, Imed; Masounave, Jacques
2010-08-01
Because of the risks associated with exposure to metallic particles, efforts are being put into controlling and reducing them during the metal working process. Recent studies by the authors involved in this project have presented the effects of cutting speeds, workpiece material, and tool geometry on particle emission during dry machining; the authors have also proposed a new parameter, named the dust unit ( D u), for use in evaluating the quantity of particle emissions relative to the quantity of chips produced during a machining operation. In this study, a model for predicting the particle emission (dust unit) during orthogonal turning is proposed. This model, which is based on the energy approach combined with the microfriction and the plastic deformation of the material, takes into account the tool geometry, the properties of the worked material, the cutting conditions, and the chip segmentation. The model is validated using experimental results obtained during the orthogonal turning of 6061-T6 aluminum alloy, AISI 1018, AISI 4140 steels, and grey cast iron. A good agreement was found with experimental results. This model can help in designing strategies for reducing particle emission during machining processes, at the source.
State orthogonality, boson bunching parameter and bosonic enhancement factor
Marchewka, Avi; Granot, Er'el
2016-04-01
It is emphasized that the bunching parameter β ≡ p B / p D , i.e. the ratio between the probability to measure two bosons and two distinguishable particles at the same state, is a constant of motion and depends only on the overlap between the initial wavefunctions. This ratio is equal to β = 2 / (1 + I 2), where I is the overlap integral between the initial wavefunctions. That is, only when the initial wavefunctions are orthogonal this ratio is equal to 2, however, this bunching ratio can be reduced to 1, when the two wavefunctions are identical. This simple equation explains the experimental evidences of a beam splitter. A straightforward conclusion is that by measuring the local bunching parameter β (at any point in space and time) it is possible to evaluate a global parameter I (the overlap between the initial wavefunctions). The bunching parameter is then generalized to arbitrary number of particles, and in an analogy to the two-particles scenario, the well-known bosonic enhancement appears only when all states are orthogonal.
State orthogonality, boson bunching parameter and bosonic enhancement factor
International Nuclear Information System (INIS)
Marchewka, A.; Granot, E.
2016-01-01
Bosons bunching is the tendency of bosons to bunch together with respect to distinguishable particles. It is emphasized that the bunching parameter β = p_B/p_D, i.e. the ratio between the probability to measure 2 bosons and 2 distinguishable particles at the same state, is a constant of motion and depends only on the overlap between the initial wavefunctions. This ratio is equal to β = 2/(1 + l"2), where l is the overlap integral between the initial wavefunctions. That is, only when the initial wavefunctions are orthogonal this ratio is equal to 2, however, this bunching ratio can be reduced to 1, when the two wavefunctions are identical. This simple equation explains the experimental evidences of a beam splitter. A straightforward conclusion is that by measuring the local bunching parameter β (at any point in space and time) it is possible to evaluate a global parameter l (the overlap between the initial wavefunctions). The bunching parameter is then generalized to arbitrary number of particles, and in an analogy to the two-particles scenario, the well-known bosonic enhancement appears only when all states are orthogonal
Supervised orthogonal discriminant subspace projects learning for face recognition.
Chen, Yu; Xu, Xiao-Hong
2014-02-01
In this paper, a new linear dimension reduction method called supervised orthogonal discriminant subspace projection (SODSP) is proposed, which addresses high-dimensionality of data and the small sample size problem. More specifically, given a set of data points in the ambient space, a novel weight matrix that describes the relationship between the data points is first built. And in order to model the manifold structure, the class information is incorporated into the weight matrix. Based on the novel weight matrix, the local scatter matrix as well as non-local scatter matrix is defined such that the neighborhood structure can be preserved. In order to enhance the recognition ability, we impose an orthogonal constraint into a graph-based maximum margin analysis, seeking to find a projection that maximizes the difference, rather than the ratio between the non-local scatter and the local scatter. In this way, SODSP naturally avoids the singularity problem. Further, we develop an efficient and stable algorithm for implementing SODSP, especially, on high-dimensional data set. Moreover, the theoretical analysis shows that LPP is a special instance of SODSP by imposing some constraints. Experiments on the ORL, Yale, Extended Yale face database B and FERET face database are performed to test and evaluate the proposed algorithm. The results demonstrate the effectiveness of SODSP. Copyright © 2013 Elsevier Ltd. All rights reserved.
Cache-Oblivious Planar Orthogonal Range Searching and Counting
DEFF Research Database (Denmark)
Arge, Lars; Brodal, Gerth Stølting; Fagerberg, Rolf
2005-01-01
present the first cache-oblivious data structure for planar orthogonal range counting, and improve on previous results for cache-oblivious planar orthogonal range searching. Our range counting structure uses O(Nlog2 N) space and answers queries using O(logB N) memory transfers, where B is the block...... size of any memory level in a multilevel memory hierarchy. Using bit manipulation techniques, the space can be further reduced to O(N). The structure can also be modified to support more general semigroup range sum queries in O(logB N) memory transfers, using O(Nlog2 N) space for three-sided queries...... and O(Nlog22 N/log2log2 N) space for four-sided queries. Based on the O(Nlog N) space range counting structure, we develop a data structure that uses O(Nlog2 N) space and answers three-sided range queries in O(logB N+T/B) memory transfers, where T is the number of reported points. Based...
USC orthogonal multiprocessor for image processing with neural networks
Hwang, Kai; Panda, Dhabaleswar K.; Haddadi, Navid
1990-07-01
This paper presents the architectural features and imaging applications of the Orthogonal MultiProcessor (OMP) system, which is under construction at the University of Southern California with research funding from NSF and assistance from several industrial partners. The prototype OMP is being built with 16 Intel i860 RISC microprocessors and 256 parallel memory modules using custom-designed spanning buses, which are 2-D interleaved and orthogonally accessed without conflicts. The 16-processor OMP prototype is targeted to achieve 430 MIPS and 600 Mflops, which have been verified by simulation experiments based on the design parameters used. The prototype OMP machine will be initially applied for image processing, computer vision, and neural network simulation applications. We summarize important vision and imaging algorithms that can be restructured with neural network models. These algorithms can efficiently run on the OMP hardware with linear speedup. The ultimate goal is to develop a high-performance Visual Computer (Viscom) for integrated low- and high-level image processing and vision tasks.
DEFF Research Database (Denmark)
A watershed moment of the twentieth century, the end of empire saw upheavals to global power structures and national identities. However, decolonisation profoundly affected individual subjectivities too. Life Writing After Empire examines how people around the globe have made sense of the post...... in order to understand how individual life writing reflects broader societal changes. From far-flung corners of the former British Empire, people have turned to life writing to manage painful or nostalgic memories, as well as to think about the past and future of the nation anew through the personal...
Theological reflections on empire
Directory of Open Access Journals (Sweden)
Allan A. Boesak
2009-11-01
Full Text Available Since the meeting of the World Alliance of Reformed Churches in Accra, Ghana (2004, and the adoption of the Accra Declaration, a debate has been raging in the churches about globalisation, socio-economic justice, ecological responsibility, political and cultural domination and globalised war. Central to this debate is the concept of empire and the way the United States is increasingly becoming its embodiment. Is the United States a global empire? This article argues that the United States has indeed become the expression of a modern empire and that this reality has considerable consequences, not just for global economics and politics but for theological refl ection as well.
An empirical framework for tropical cyclone climatology
Energy Technology Data Exchange (ETDEWEB)
Kang, Nam-Young [Korea Meteorological Administration, Seoul (Korea, Republic of); Florida State University, Tallahassee, FL (United States); Elsner, James B. [Florida State University, Tallahassee, FL (United States)
2012-08-15
An empirical approach for analyzing tropical cyclone climate is presented. The approach uses lifetime-maximum wind speed and cyclone frequency to induce two orthogonal variables labeled ''activity'' and ''efficiency of intensity''. The paired variations of activity and efficiency of intensity along with the opponent variations of frequency and intensity configure a framework for evaluating tropical cyclone climate. Although cyclone activity as defined in this framework is highly correlated with the commonly used exponent indices like accumulated cyclone energy, it does not contain cyclone duration. Empirical quantiles are used to determine threshold intensity levels, and variant year ranges are used to find consistent trends in tropical cyclone climatology. In the western North Pacific, cyclone activity is decreasing despite increases in lifetime-maximum intensity. This is due to overwhelming decreases in cyclone frequency. These changes are also explained by an increasing efficiency of intensity. The North Atlantic shows different behavior. Cyclone activity is increasing due to increasing frequency and, to a lesser extent, increasing intensity. These changes are also explained by a decreasing efficiency of intensity. Tropical cyclone trends over the North Atlantic basin are more consistent over different year ranges than tropical cyclone trends over the western North Pacific. (orig.)
Decomposition of orthogonal polygons in a set of rectanglеs
Shestakov, E.; Voronov, A.
2009-01-01
Algorithm for covering orthogonal integrated circuit layout objects is considered. Objects of the research are special single-connected orthogonal polygons which are generated during decomposition of any multiply connected polygon in a set of single-connected orthogonal polygons. Developed algorithm for covering polygons based on the mathematical techinque of logic matrix transformation. Results described in this paper, can be applied in computer geometry and image analysis.
A high-order q-difference equation for q-Hahn multiple orthogonal polynomials
DEFF Research Database (Denmark)
Arvesú, J.; Esposito, Chiara
2012-01-01
A high-order linear q-difference equation with polynomial coefficients having q-Hahn multiple orthogonal polynomials as eigenfunctions is given. The order of the equation coincides with the number of orthogonality conditions that these polynomials satisfy. Some limiting situations when are studie....... Indeed, the difference equation for Hahn multiple orthogonal polynomials given in Lee [J. Approx. Theory (2007), ), doi: 10.1016/j.jat.2007.06.002] is obtained as a limiting case....
African Journals Online (AJOL)
FIRST LADY
2011-01-18
Jan 18, 2011 ... Empirical results reveal that consumption of sugar in. Kenya varies ... experiences in trade in different regions of the world. Some studies ... To assess the relationship between domestic sugar retail prices and sugar sales in ...
Wu, Zhaohua; Feng, Jiaxin; Qiao, Fangli; Tan, Zhe-Min
2016-04-13
In this big data era, it is more urgent than ever to solve two major issues: (i) fast data transmission methods that can facilitate access to data from non-local sources and (ii) fast and efficient data analysis methods that can reveal the key information from the available data for particular purposes. Although approaches in different fields to address these two questions may differ significantly, the common part must involve data compression techniques and a fast algorithm. This paper introduces the recently developed adaptive and spatio-temporally local analysis method, namely the fast multidimensional ensemble empirical mode decomposition (MEEMD), for the analysis of a large spatio-temporal dataset. The original MEEMD uses ensemble empirical mode decomposition to decompose time series at each spatial grid and then pieces together the temporal-spatial evolution of climate variability and change on naturally separated timescales, which is computationally expensive. By taking advantage of the high efficiency of the expression using principal component analysis/empirical orthogonal function analysis for spatio-temporally coherent data, we design a lossy compression method for climate data to facilitate its non-local transmission. We also explain the basic principles behind the fast MEEMD through decomposing principal components instead of original grid-wise time series to speed up computation of MEEMD. Using a typical climate dataset as an example, we demonstrate that our newly designed methods can (i) compress data with a compression rate of one to two orders; and (ii) speed-up the MEEMD algorithm by one to two orders. © 2016 The Authors.
Moore, R. K.; Fung, A. K.; Dome, G. J.; Birrer, I. J.
1978-01-01
The wind direction properties of radar backscatter from the sea were empirically modelled using a cosine Fourier series through the 4th harmonic in wind direction (referenced to upwind). A comparison with 1975 JONSWAP (Joint North Sea Wave Project) scatterometer data, at incidence angles of 40 and 65, indicates that effects to third and fourth harmonics are negligible. Another important result is that the Fourier coefficients through the second harmonic are related to wind speed by a power law expression. A technique is also proposed to estimate the wind speed and direction over the ocean from two orthogonal scattering measurements. A comparison between two different types of sea scatter theories, one type presented by the work of Wright and the other by that of Chan and Fung, was made with recent scatterometer measurements. It demonstrates that a complete scattering model must include some provisions for the anisotropic characteristics of the sea scatter, and use a sea spectrum which depends upon wind speed.
Directory of Open Access Journals (Sweden)
Brad W. Watson
2016-11-01
Full Text Available Nanostructuring organic polymers and organic/inorganic hybrid materials and controlling blend morphologies at the molecular level are the prerequisites for modern electronic devices including biological sensors, light emitting diodes, memory devices and solar cells. To achieve all-around high performance, multiple organic and inorganic entities, each designed for specific functions, are commonly incorporated into a single device. Accurate arrangement of these components is a crucial goal in order to achieve the overall synergistic effects. We describe here a facile methodology of nanostructuring conjugated polymers and inorganic quantum dots into well-ordered core/shell composite nanofibers through cooperation of several orthogonal non-covalent interactions including conjugated polymer crystallization, block copolymer self-assembly and coordination interactions. Our methods provide precise control on the spatial arrangements among the various building blocks that are otherwise incompatible with one another, and should find applications in modern organic electronic devices such as solar cells.
Yan, Jie-Yun
2017-08-01
The theory of excitonic high-order sideband generation (HSG) in a semiconductor quantum well irradiated by two orthogonal terahertz (THz) fields (one frequency is an integral multiple of the other) is presented. The exact analytical solution to the sideband spectrum is given with the help of the generalized Bessel functions. As a special case, the HSG when the frequencies of these two THz fields are the same is derived and its dependence on the ellipticity of the THz field is discussed. The theory could explain the experiments, especially concerning the sensitive dependence of HSG signals on the ellipticity of the THz field: the signals are strong when the THz field has a linear polarization and totally vanish in case of a circular polarization. More interestingly, it was found that the strongest signal is not produced in the case of linear polarization for some sidebands. The theory is supported by numerical calculations.
Orthogonal dual-modification of proteins for the engineering of multivalent protein scaffolds
Directory of Open Access Journals (Sweden)
Michaela Mühlberg
2015-05-01
Full Text Available To add new tools to the repertoire of protein-based multivalent scaffold design, we have developed a novel dual-labeling strategy for proteins that combines residue-specific incorporation of unnatural amino acids with chemical oxidative aldehyde formation at the N-terminus of a protein. Our approach relies on the selective introduction of two different functional moieties in a protein by mutually orthogonal copper-catalyzed azide–alkyne cycloaddition (CuAAC and oxime ligation. This method was applied to the conjugation of biotin and β-linked galactose residues to yield an enzymatically active thermophilic lipase, which revealed specific binding to Erythrina cristagalli lectin by SPR binding studies.
Study on energy saving of subway station based on orthogonal experimental method
Guo, Lei
2017-05-01
With the characteristics of quick, efficient and large amount transport, the subway has become an important way to solve urban traffic congestion. As the subway environment will follow the change of external environment factors such as temperature and load of personnel changes, three-dimensional numerical simulations study is conducted by using CFD software for air distribution of subway platform. The influence of different loads (the supply air temperature and velocity of air condition, personnel load, heat flux of the wall) on the subway platform flow field are also analysed. The orthogonal experiment method is applied to the numerical simulation analysis for human comfort under different parameters. Based on those results, the functional relationship between human comfort and the boundary conditions of the platform is produced by multiple linear regression fitting method, the order of major boundary conditions which affect human comfort is obtained. The above study provides a theoretical basis for the final energy-saving strategies.
Design of Extended Depth-of-Focus Laser Beams Using Orthogonal Beam Expansions
Directory of Open Access Journals (Sweden)
Leonard Bergstein
2005-06-01
Full Text Available Laser beams with extended depth of focus have many practical applications, such as scanning printed bar codes. Previous work has concentrated on synthesizing such beams by approximating the nondiffracting Bessel beam solution to the wave equation. In this paper, we introduce an alternate novel synthesis method that is based on maintaining a minimum MTF value (contrast over the largest possible distance. To achieve this, the coefficients of an orthogonal beam expansion are sequentially optimized to this criterion. One of the main advantages of this method is that it can be easily generalized to noncircularly symmetrical beams by the appropriate choice of the beam expansion basis functions. This approach is found to be very useful for applications that involve scanning of the laser beam.
International Nuclear Information System (INIS)
Fortini, Maria A.; Stamoulis, Michel N.; Ferreira, Angela F.M.; Pereira, Claubia; Costa, Antonella L.; Silva, Clarysson A.M.
2008-01-01
In this work, an analytical model for the determination of the temperature distribution in cylindrical heater components with characteristics of nuclear fuel rods, is presented. The heat conductor is characterized by an arbitrary number of solid walls and different types of materials, whose thermal properties are taken as function of temperature. The heat conduction fundamental equation is solved numerically with the method of weighted residuals (MWR) using a technique of orthogonal collocation. The results obtained with the proposed method are compared with the experimental data from tests performed in the TRIGA IPR-R1 research reactor localized at the CDTN/CNEN (Centro de Desenvolvimento da Tecnologia Nuclear/Comissao Nacional de Energia Nuclear) at Belo Horizonte in Brazil
Zhang, Xue-Jian; Wang, Xiao-Wei; Sun, Jiaxing; Su, Chao; Yang, Shuguang; Zhang, Wen-Bin
2018-05-16
Protein immobilization is critical to utilize their unique functions in diverse applications. Herein, we report that orthogonal peptide-protein chemistry enabled multilayer construction can facilitate the incorporation of various folded structural domains, including calmodulin in different states, affibody and dihydrofolate reductase (DHFR). An extended conformation is found to be the most advantageous for steady film growth. The resulting protein thin films exhibit sensitive and selective responsive behaviors to bio-signals (Ca2+, TFP, NADPH, etc.) and fully maintain the catalytic activity of DHFR. The approach is applicable to different substrates such as hydrophobic gold and hydrophilic silica microparticles. The DHFR enzyme can be immobilized onto silica microparticles with tunable amounts. The multi-layer set-up exhibits a synergistic enhancement of DHFR activity with increasing number of bilayers and also makes the embedded DHFR more resilient to lyophilization. Therefore, this is a convenient and versatile method for protein immobilization with potential benefits of synergistic enhancement in enzyme performance and resilience.
International Nuclear Information System (INIS)
Eliassen, Lene; Andersen, Søren
2016-01-01
The wind turbine design standards recommend two different methods to generate turbulent wind for design load analysis, the Kaimal spectra combined with an exponential coherence function and the Mann turbulence model. The two turbulence models can give very different estimates of fatigue life, especially for offshore floating wind turbines. In this study the spatial distributions of the two turbulence models are investigated using Proper Orthogonal Decomposition, which is used to characterize large coherent structures. The main focus has been on the structures that contain the most energy, which are the lowest POD modes. The Mann turbulence model generates coherent structures that stretches in the horizontal direction for the longitudinal component, while the structures found in the Kaimal model are more random in their shape. These differences in the coherent structures at lower frequencies for the two turbulence models can be the reason for differences in fatigue life estimates for wind turbines. (paper)
Reinhardt, Jan D; Zhang, Xia; Prodinger, Birgit; Ehrmann-Bostan, Cristina; Selb, Melissa; Stucki, Gerold; Li, Jianan
2016-06-13
The aims of this study were to evaluate the feasibility of using the International Classification of Functioning, Disability and Health (ICF) Generic Set in routine clinical practice, and of creating a functioning score based on it, and, subsequently, to examine its sensitivity to change. In this prospective cohort study, data from 761 adult inpatients from 21 Chinese hospitals were analysed. Each patient was assessed at admission and discharge. Feasibility was evaluated by analysing mean assessment time. The Rasch model was used to create a metric of functioning. Sensitivity to change was analysed with mixed-effects regression and by calculating standardized effect size based on Cohen's f2. Mean duration of assessment was 5.3 min, with a significant decrease between admission and discharge. After removal of the item remunerative employment, the remaining ICF Generic Set categories fitted the Rasch model well. With a mean improvement in functioning of 12.1 (95% confidence interval (95% CI): 11.5-12.6), this metric proved sensitive to change, both in terms of statistical significance (p ICF Generic Set is feasible for use in routine clinical practice and is promising to serve as the basis for the development of a functioning score that is sensitive to change.
Directory of Open Access Journals (Sweden)
Asger Nyman Christiansen
2012-11-01
Full Text Available Currently, no objective method exists for estimating the rate of change in the colour of meat. Consequently, the purpose of this work is to develop a procedure capable of monitoring the change in colour of meat over time, environment and ingredients. This provides a useful tool to determine which storage environments and ingredients a manufacturer should add to meat to reduce the rate of change in colour. The procedure consists of taking multi-spectral images of a piece of meat as a function of time, clustering the pixels of these images into categories, including several types of meat, and extracting colour information from each category. The focus has primarily been on achieving an accurate categorisation since this is crucial to develop a useful method. The categorisation is done by applying an orthogonal transformation followed by k-means clustering. The purpose of the orthogonal transformation is to reduce the noise and amount of data while enhancing the difference between the categories. The orthogonal transformations principal components analysis, minimum noise fraction analysis and kernel-based versions of these have been applied to test which produce the most accurate categorisation.
Self-assembly of orthogonal three-axis sensors
International Nuclear Information System (INIS)
Cho, J. H.; Hu, S.; Gracias, D. H.
2008-01-01
Conventional planar microfabrication is widely utilized to construct sensors for the measurement of physical or chemical properties. However, in these devices, the information component measured is typically restricted to only one vectorial axis. Here, we describe a self-assembling strategy that can be utilized to construct three dimensional (3D) cubic devices that facilitate measurement along three axes. This 3D measurement is achieved by arranging sensing elements orthogonally; any sensing element that can be lithographically patterned can be utilized. The 3D arrangement of sensors allows for the measurement of angular and orientation parameters. As an example, we describe a three-axis cantilever based sensor and demonstrate measurement of an evaporated analyte using resonant frequency shifts of cantilevers in each of the x, y, and z axes
Study of α-16O scattering by orthogonality condition models
International Nuclear Information System (INIS)
Breitschaft, A.M.; Canto, L.F.; Schechter, H.
1983-01-01
The use of approximate microscopic theories in α- 16 O scattering is investigated. The Orthogonality Condition Model (OCM) with both the direct potential of the Resonating Group Method (RMG) and with an effective local potential, V sub(eff), derived from Kernels of Generator Coordinate Method (GCM) is employed to study collisions at CM energies up to 30 MeV, for all relevant partial waves. Although the predictions of the OCM are consistent with 'exact' RGM results in both cases, the nuclear phase-shifts obtained with the effective potential are better. The presence of ambiguities in the derivation of V sub(eff) is noticed. The nature of such ambiguities is discussed. (Author) [pt
Study of α-16O scattering by orthogonality condition models
International Nuclear Information System (INIS)
Breitschaft, A.M.; Canto, L.F.; Schechter, H.
1982-01-01
The use of approximate microscopic theories in α- 16 O scattering is investigated. The Orthogonality Condition Model (OCM) with the direct potential of the Resonating Group Method (RGM) and with an effective local potential V sub(eff') derived from Kernels of the Generator Coordinate Method (GCM) is employed to study collisions at CM energies up to 30 MeV, for all relevant partial waves. Although the predictions of the OCM are consistent with 'exact' RGM results in both cases, the nuclear phase-shifts obtained with the effective potential are better. It is noticed the presence of ambiguities in the derivation of V sub(eff'). The nature of such ambiguities is discussed. (Author) [pt
Landmine detection using two-tapped joint orthogonal matching pursuits
Goldberg, Sean; Glenn, Taylor; Wilson, Joseph N.; Gader, Paul D.
2012-06-01
Joint Orthogonal Matching Pursuits (JOMP) is used here in the context of landmine detection using data obtained from an electromagnetic induction (EMI) sensor. The response from an object containing metal can be decomposed into a discrete spectrum of relaxation frequencies (DSRF) from which we construct a dictionary. A greedy iterative algorithm is proposed for computing successive residuals of a signal by subtracting away the highest matching dictionary element at each step. The nal condence of a particular signal is a combination of the reciprocal of this residual and the mean of the complex component. A two-tap approach comparing signals on opposite sides of the geometric location of the sensor is examined and found to produce better classication. It is found that using only a single pursuit does a comparable job, reducing complexity and allowing for real-time implementation in automated target recognition systems. JOMP is particularly highlighted in comparison with a previous EMI detection algorithm known as String Match.
Downlink scheduling using non-orthogonal uplink beams
Eltayeb, Mohammed E.
2014-04-01
Opportunistic schedulers rely on the feedback of the channel state information of users in order to perform user selection and downlink scheduling. This feedback increases with the number of users, and can lead to inefficient use of network resources and scheduling delays. We tackle the problem of feedback design, and propose a novel class of nonorthogonal codes to feed back channel state information. Users with favorable channel conditions simultaneously transmit their channel state information via non-orthogonal beams to the base station. The proposed formulation allows the base station to identify the strong users via a simple correlation process. After deriving the minimum required code length and closed-form expressions for the feedback load and downlink capacity, we show that i) the proposed algorithm reduces the feedback load while matching the achievable rate of full feedback algorithms operating over a noiseless feedback channel, and ii) the proposed codes are superior to the Gaussian codes.
Orthogonally Evolved AI to Improve Difficulty Adjustment in Video Games
DEFF Research Database (Denmark)
Hintze, Arend; Olson, Randal; Lehman, Joel Anthony
2016-01-01
Computer games are most engaging when their difficulty is well matched to the player's ability, thereby providing an experience in which the player is neither overwhelmed nor bored. In games where the player interacts with computer-controlled opponents, the difficulty of the game can be adjusted...... not only by changing the distribution of opponents or game resources, but also through modifying the skill of the opponents. Applying evolutionary algorithms to evolve the artificial intelligence that controls opponent agents is one established method for adjusting opponent difficulty. Less-evolved agents...... (i.e. agents subject to fewer generations of evolution) make for easier opponents, while highly-evolved agents are more challenging to overcome. In this publication we test a new approach for difficulty adjustment in games: orthogonally evolved AI, where the player receives support from collaborating...
Downlink scheduling using non-orthogonal uplink beams
Eltayeb, Mohammed E.; Al-Naffouri, Tareq Y.; Bahrami, Hamid Reza Talesh
2014-01-01
Opportunistic schedulers rely on the feedback of the channel state information of users in order to perform user selection and downlink scheduling. This feedback increases with the number of users, and can lead to inefficient use of network resources and scheduling delays. We tackle the problem of feedback design, and propose a novel class of nonorthogonal codes to feed back channel state information. Users with favorable channel conditions simultaneously transmit their channel state information via non-orthogonal beams to the base station. The proposed formulation allows the base station to identify the strong users via a simple correlation process. After deriving the minimum required code length and closed-form expressions for the feedback load and downlink capacity, we show that i) the proposed algorithm reduces the feedback load while matching the achievable rate of full feedback algorithms operating over a noiseless feedback channel, and ii) the proposed codes are superior to the Gaussian codes.
Orthogonal views improves localisation in bone scans of wrist
International Nuclear Information System (INIS)
Roth, A.L.
1997-01-01
Full text: Of all nuclear medicine studies, bone scans are the most fundamental. However, straightforward these may seem, there are always mechanisms that can be implemented which assist in a more precise diagnosis, particularly in areas with an intricate bone structure. An 18-year-old right-handed student presented to her doctor with a one month history of pain over the right distal radio-ulna joint area. Clinically, she had prominence of the right ulna, which suggested that there may have been a previous injury to the wrist. Also, pronation/supination were painful where there was swelling of the extensor carpi ulnaris tendon, as well as some discomfort with clicking in ulna deviation/rotation. The X-rays demonstrated some premature radial epiphysial closure. A bone scan was requested to attempt to localise the main inflammatory focus. The dynamic study was performed in the planar projection with an immediate blood pool for 300k being taken. These demonstrated a vascular blush medially. A medial blood pool image was acquired and it localised the abnormal vascularity as being dorsal. A separate focal area of less intense blood pooling was also noted in the line of the distal ulna. Delayed images showed increased uptake localised to the ulna styloid. Anatomically, the superficial vascular blush correlated with tenosynovitis. Hence, the orthogonal initial and delayed images were definitive in the diagnoses of tenosynovitis of the extensor carpi ulnaris tendon. This clearly complements the information provided by the palmar view. However, it is important to remember that an increased radiation dose to the technologist is incurred as a result of the extra orthogonal view, hence attention to technique is imperative
Orthogonal views improves localisation in bone scans of wrist
Energy Technology Data Exchange (ETDEWEB)
Roth, A.L.
1997-09-01
Full text: Of all nuclear medicine studies, bone scans are the most fundamental. However, straightforward these may seem, there are always mechanisms that can be implemented which assist in a more precise diagnosis, particularly in areas with an intricate bone structure. An 18-year-old right-handed student presented to her doctor with a one month history of pain over the right distal radio-ulna joint area. Clinically, she had prominence of the right ulna, which suggested that there may have been a previous injury to the wrist. Also, pronation/supination were painful where there was swelling of the extensor carpi ulnaris tendon, as well as some discomfort with clicking in ulna deviation/rotation. The X-rays demonstrated some premature radial epiphysial closure. A bone scan was requested to attempt to localise the main inflammatory focus. The dynamic study was performed in the planar projection with an immediate blood pool for 300k being taken. These demonstrated a vascular blush medially. A medial blood pool image was acquired and it localised the abnormal vascularity as being dorsal. A separate focal area of less intense blood pooling was also noted in the line of the distal ulna. Delayed images showed increased uptake localised to the ulna styloid. Anatomically, the superficial vascular blush correlated with tenosynovitis. Hence, the orthogonal initial and delayed images were definitive in the diagnoses of tenosynovitis of the extensor carpi ulnaris tendon. This clearly complements the information provided by the palmar view. However, it is important to remember that an increased radiation dose to the technologist is incurred as a result of the extra orthogonal view, hence attention to technique is imperative.
Directory of Open Access Journals (Sweden)
Yu Guo
2014-06-01
Full Text Available This study examines the relationship between Internet use and social capital in an intercultural context and investigates how different Internet use functions are related to social capital. Data were collected from the survey among 155 Chinese international students studying in Japan’s universities. The results showed that Internet use intensity negatively influenced individuals’ bonding social capital. It was also found that the use of the Internet for staying informed would have positive effects on bridging social capital. However, no significant relationship was found between using the Internet for interacting with others and the two types of social capital. These findings fill the gaps in existing studies on Internet effectiveness and help to provide knowledge about the influences of various Internet use functions on establishing and maintaining social ties.
Nik Mustaffa, Nik Azah Karimah
2009-01-01
This paper is prepared to understand an organization moves towards establishing financial shared service as a strategic finance function. The research is conducted by selected few multinational organizations from oil and gas industry to analyze the purpose of the move, how organizations are restructure and values generated from the financial shared services. The research also will extend towards identifying various challenges faced by the organizations during the restructuring process. The is...
Hadjmohammadi, Mohammad Reza; S J Nazari, S Saman
2013-08-01
The separation optimization of aniline and seven 4-substituted derivatives in high-submicellar LC was performed using an interpretive optimization strategy and Derringer's desirability function. Description of the retention of solutes was carried out through several hyperbolic and logarithmic retention models using the retention data of five mobile phases of SDS (0.06-0.12 M) and methanol (50-70% v/v) at pH 3. Among the investigated models, a logarithmic retention model logk=c0+c1φ+c2[S]+c12φ[S]+d12(φ[S])0.5 showed the best prediction capability and was used to predict the solute retention factors. A grid search program was used to calculate the retention times of each solute, based on the best retention model, for all combinations of SDS and methanol concentrations in the factor space. Two different chromatographic goals, analysis time and retention differences between adjacent peaks, were evaluated simultaneously using Derringer's desirability function for each mobile phase conditions in the grid search. Optimal mobile phase composition for separation of eight anilines was found to be 0.119 M SDS and 53% v/v methanol. Under these conditions, full resolutions with a reasonable analysis time (22 min) were obtained. At the optimal condition, a good agreement was observed between predicted and experimental values of the retention times. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Empirical philosophy of science
DEFF Research Database (Denmark)
Wagenknecht, Susann; Nersessian, Nancy J.; Andersen, Hanne
2015-01-01
A growing number of philosophers of science make use of qualitative empirical data, a development that may reconfigure the relations between philosophy and sociology of science and that is reminiscent of efforts to integrate history and philosophy of science. Therefore, the first part...... of this introduction to the volume Empirical Philosophy of Science outlines the history of relations between philosophy and sociology of science on the one hand, and philosophy and history of science on the other. The second part of this introduction offers an overview of the papers in the volume, each of which...... is giving its own answer to questions such as: Why does the use of qualitative empirical methods benefit philosophical accounts of science? And how should these methods be used by the philosopher?...
Directory of Open Access Journals (Sweden)
Chih-Cheng Lu
2015-06-01
Full Text Available A new class of tri-axial miniature magnetometer consisting of a planar fluxgate structure with an orthogonal ferromagnetic fluxguide centrally situated over the magnetic cores is presented. The magnetic sensor possesses a cruciform ferromagnetic core placed diagonally upon the square excitation coil under which two pairs of pick-up coils for in-plane field detection are allocated. Effective principles and analysis of the magnetometer for 3-D field vectors are described and verified by numerically electromagnetic simulation for the excitation and magnetization of the ferromagnetic cores. The sensor is operated by applying the second-harmonic detection technique that can verify V-B relationship and device responsivity. Experimental characterization of the miniature fluxgate device demonstrates satisfactory spatial magnetic field detection results in terms of responsivity and noise spectrum. As a result, at an excitation frequency of 50 kHz, a maximum in-plane responsivity of 122.4 V/T appears and a maximum out-of-plane responsivity of 11.6 V/T is obtained as well. The minimum field noise spectra are found to be 0.11 nT/√Hz and 6.29 nT/√Hz, respectively, in X- and Z-axis at 1 Hz under the same excitation frequency. Compared with the previous tri-axis fluxgate devices, this planar magnetic sensor with an orthogonal fluxguide provides beneficial enhancement in both sensory functionality and manufacturing simplicity. More importantly, this novel device concept is considered highly suitable for the extension to a silicon sensor made by the current CMOS-MEMS technologies, thus emphasizing its emerging applications of field detection in portable industrial electronics.
Lu, Chih-Cheng; Huang, Jeff
2015-06-19
A new class of tri-axial miniature magnetometer consisting of a planar fluxgate structure with an orthogonal ferromagnetic fluxguide centrally situated over the magnetic cores is presented. The magnetic sensor possesses a cruciform ferromagnetic core placed diagonally upon the square excitation coil under which two pairs of pick-up coils for in-plane field detection are allocated. Effective principles and analysis of the magnetometer for 3-D field vectors are described and verified by numerically electromagnetic simulation for the excitation and magnetization of the ferromagnetic cores. The sensor is operated by applying the second-harmonic detection technique that can verify V-B relationship and device responsivity. Experimental characterization of the miniature fluxgate device demonstrates satisfactory spatial magnetic field detection results in terms of responsivity and noise spectrum. As a result, at an excitation frequency of 50 kHz, a maximum in-plane responsivity of 122.4 V/T appears and a maximum out-of-plane responsivity of 11.6 V/T is obtained as well. The minimum field noise spectra are found to be 0.11 nT/√Hz and 6.29 nT/√Hz, respectively, in X- and Z-axis at 1 Hz under the same excitation frequency. Compared with the previous tri-axis fluxgate devices, this planar magnetic sensor with an orthogonal fluxguide provides beneficial enhancement in both sensory functionality and manufacturing simplicity. More importantly, this novel device concept is considered highly suitable for the extension to a silicon sensor made by the current CMOS-MEMS technologies, thus emphasizing its emerging applications of field detection in portable industrial electronics.
Beccati, Daniela; Lech, Miroslaw; Ozug, Jennifer; Gunay, Nur Sibel; Wang, Jing; Sun, Elaine Y; Pradines, Joël R; Farutin, Victor; Shriver, Zachary; Kaundinya, Ganesh V; Capila, Ishan
2017-02-01
Heparan sulfate (HS), a glycosaminoglycan present on the surface of cells, has been postulated to have important roles in driving both normal and pathological physiologies. The chemical structure and sulfation pattern (domain structure) of HS is believed to determine its biological function, to vary across tissue types, and to be modified in the context of disease. Characterization of HS requires isolation and purification of cell surface HS as a complex mixture. This process may introduce additional chemical modification of the native residues. In this study, we describe an approach towards thorough characterization of bovine kidney heparan sulfate (BKHS) that utilizes a variety of orthogonal analytical techniques (e.g. NMR, IP-RPHPLC, LC-MS). These techniques are applied to characterize this mixture at various levels including composition, fragment level, and overall chain properties. The combination of these techniques in many instances provides orthogonal views into the fine structure of HS, and in other instances provides overlapping / confirmatory information from different perspectives. Specifically, this approach enables quantitative determination of natural and modified saccharide residues in the HS chains, and identifies unusual structures. Analysis of partially digested HS chains allows for a better understanding of the domain structures within this mixture, and yields specific insights into the non-reducing end and reducing end structures of the chains. This approach outlines a useful framework that can be applied to elucidate HS structure and thereby provides means to advance understanding of its biological role and potential involvement in disease progression. In addition, the techniques described here can be applied to characterization of heparin from different sources.
Representations for the extreme zeros of orthogonal polynomials (vol 233, pg 847, 2009)
van Doorn, Erik A.; van Foreest, Nicky D.; Zeifman, Alexander I.
2013-01-01
We correct representations for the endpoints of the true interval of orthogonality of a sequence of orthogonal polynomials that were stated by us in the Journal of Computational and Applied Mathematics 233 (2009) 847-851. (c) 2013 Elsevier B.V. All rights reserved.
Bio-inspired supramolecular materials by orthogonal self-assembly of hydrogelators and phospholipids
Boekhoven, J.; Brizard, AMA; Stuart, M. C A; Florusse, L.J.; Raffy, G.; Del Guerzo, A.; van Esch, J.H.
2016-01-01
The orthogonal self-assembly of multiple components is a powerful strategy towards the formation of complex biomimetic architectures, but so far the rules for designing such systems are unclear. Here we show how to identify orthogonal self-assembly at the supramolecular level and describe
Aspects of Orthogonality in the Development of the National Digital Wealth (NDW
Directory of Open Access Journals (Sweden)
Ion IVAN
2014-01-01
Full Text Available There are presented aspects of orthogonality in the development of the national digital wealth. There is presented the concept of NDW. Are identified quality characteristics. Are built orthogonality metrics for software development applications which are parts of NDW.
2017-10-01
AWARD NUMBER: W81XWH-16-1-0595 TITLE: Prostate-Specific Membrane Antigen (PSMA) Targeted Bio -orthogonal Therapy for Metastatic Prostate Cancer...Sep 2016 - 14 Sep 2017 4. TITLE AND SUBTITLE Prostate-Specific Membrane Antigen (PSMA) Targeted Bio -orthogonal Therapy for Metastatic Prostate
DEFF Research Database (Denmark)
Gravier, Magali
2011-01-01
The article discusses the concepts of federation and empire in the context of the European Union (EU). Even if these two concepts are not usually contrasted to one another, the article shows that they refer to related type of polities. Furthermore, they can be used at a time because they shed light...... on different and complementary aspects of the European integration process. The article concludes that the EU is at the crossroads between federation and empire and may remain an ‘imperial federation’ for several decades. This could mean that the EU is on the verge of transforming itself to another type...
Empirical comparison of theories
International Nuclear Information System (INIS)
Opp, K.D.; Wippler, R.
1990-01-01
The book represents the first, comprehensive attempt to take an empirical approach for comparative assessment of theories in sociology. The aims, problems, and advantages of the empirical approach are discussed in detail, and the three theories selected for the purpose of this work are explained. Their comparative assessment is performed within the framework of several research projects, which among other subjects also investigate the social aspects of the protest against nuclear power plants. The theories analysed in this context are the theory of mental incongruities and that of the benefit, and their efficiency in explaining protest behaviour is compared. (orig./HSCH) [de
DEFF Research Database (Denmark)
Grund, Cynthia M.
The toolbox for empirically exploring the ways that artistic endeavors convey and activate meaning on the part of performers and audiences continues to expand. Current work employing methods at the intersection of performance studies, philosophy, motion capture and neuroscience to better understand...... musical performance and reception is inspired by traditional approaches within aesthetics, but it also challenges some of the presuppositions inherent in them. As an example of such work I present a research project in empirical music aesthetics begun last year and of which I am a team member....
Orthogonal optimization of a water hydraulic pilot-operated pressure-reducing valve
Mao, Xuyao; Wu, Chao; Li, Bin; Wu, Di
2017-12-01
In order to optimize the comprehensive characteristics of a water hydraulic pilot-operated pressure-reducing valve, numerical orthogonal experimental design was adopted. Six parameters of the valve, containing diameters of damping plugs, volume of spring chamber, half cone angle of main spool, half cone angle of pilot spool, mass of main spool and diameter of main spool, were selected as the orthogonal factors, and each factor has five different levels. An index of flowrate stability, pressure stability and pressure overstrike stability (iFPOS) was used to judge the merit of each orthogonal attempt. Embedded orthogonal process turned up and a final optimal combination of these parameters was obtained after totally 50 numerical orthogonal experiments. iFPOS could be low to a fairly low value which meant that the valve could have much better stabilities. During the optimization, it was also found the diameters of damping plugs and main spool played important roles in stability characteristics of the valve.
International Nuclear Information System (INIS)
Ludwig, Catherine; Ribaupierre, Anik de; Chicherio, Christian; Terraneo, Luc; Magistretti, Pierre; Slosman, Daniel
2008-01-01
Functional activation protocols are widely applied for the study of brain-cognition relations. Only few take advantage of the intrinsic characteristics of SPECT, particularly those allowing cognitive assessment outside of the camera, in settings close to the standard clinical or laboratory ones. The purpose of the study was to assess the feasibility of a split-dose activation protocol with 99m Tc-HMPAO using low irradiation dose. A two-scans protocol was applied to 12 healthy young volunteers using 270 MBq of 99m Tc-HMPAO per scan, with each image associated to a particular experimental condition of the verbal n-back working memory task (0-back, 2-back). Subtraction method was used to identify regional brain activity related to the task. Voxel-wise statistical analysis showed left lateralized activity associated with the 2-back task, compared to the 0-back task. Activated regions, mainly prefrontal and parietal, were similar to those observed in previous fMRI and 15 O-PET studies. The results support the use of 99m Tc-HMPAO SPECT for the investigation of brain-cognition relations and demonstrate the feasibility of optimal quality images despite low radiopharmaceutical doses. The findings also acknowledge the use of HMPAO as a radioligand to capture neuro-energetic modulations linked to cognitive activity. They encourage extending the application of the described activation protocol to clinical populations. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Ludwig, Catherine; Ribaupierre, Anik de [University of Geneva, Center for Interdisciplinary Gerontology, Geneva (Switzerland); Chicherio, Christian [Max Planck Institute for Human Development, Center for Lifespan Psychology, Berlin (Germany); Terraneo, Luc [Geneva University Hospitals, Service of Nuclear Medicine, Geneva (Switzerland); Magistretti, Pierre [EPFL, Brain Mind Institute, Lausanne (Switzerland); Slosman, Daniel [Clinique Generale-Beaulieu, Nuclear Medicine Institute, Geneva (Switzerland)
2008-04-15
Functional activation protocols are widely applied for the study of brain-cognition relations. Only few take advantage of the intrinsic characteristics of SPECT, particularly those allowing cognitive assessment outside of the camera, in settings close to the standard clinical or laboratory ones. The purpose of the study was to assess the feasibility of a split-dose activation protocol with {sup 99m}Tc-HMPAO using low irradiation dose. A two-scans protocol was applied to 12 healthy young volunteers using 270 MBq of {sup 99m}Tc-HMPAO per scan, with each image associated to a particular experimental condition of the verbal n-back working memory task (0-back, 2-back). Subtraction method was used to identify regional brain activity related to the task. Voxel-wise statistical analysis showed left lateralized activity associated with the 2-back task, compared to the 0-back task. Activated regions, mainly prefrontal and parietal, were similar to those observed in previous fMRI and {sup 15}O-PET studies. The results support the use of {sup 99m}Tc-HMPAO SPECT for the investigation of brain-cognition relations and demonstrate the feasibility of optimal quality images despite low radiopharmaceutical doses. The findings also acknowledge the use of HMPAO as a radioligand to capture neuro-energetic modulations linked to cognitive activity. They encourage extending the application of the described activation protocol to clinical populations. (orig.)
Empirical research through design
Keyson, D.V.; Bruns, M.
2009-01-01
This paper describes the empirical research through design method (ERDM), which differs from current approaches to research through design by enforcing the need for the designer, after a series of pilot prototype based studies, to a-priori develop a number of testable interaction design hypothesis
Essays in empirical microeconomics
Péter, A.N.
2016-01-01
The empirical studies in this thesis investigate various factors that could affect individuals' labor market, family formation and educational outcomes. Chapter 2 focuses on scheduling as a potential determinant of individuals' productivity. Chapter 3 looks at the role of a family factor on
Worship, Reflection, Empirical Research
Ding Dong,
2012-01-01
In my youth, I was a worshipper of Mao Zedong. From the latter stage of the Mao Era to the early years of Reform and Opening, I began to reflect on Mao and the Communist Revolution he launched. In recent years I’ve devoted myself to empirical historical research on Mao, seeking the truth about Mao and China’s modern history.
DEFF Research Database (Denmark)
Bang, Peter Fibiger
2007-01-01
This articles seeks to establish a new set of organizing concepts for the analysis of the Roman imperial economy from Republic to late antiquity: tributary empire, port-folio capitalism and protection costs. Together these concepts explain better economic developments in the Roman world than the...
Empirically sampling Universal Dependencies
DEFF Research Database (Denmark)
Schluter, Natalie; Agic, Zeljko
2017-01-01
Universal Dependencies incur a high cost in computation for unbiased system development. We propose a 100% empirically chosen small subset of UD languages for efficient parsing system development. The technique used is based on measurements of model capacity globally. We show that the diversity o...
Large Covariance Estimation by Thresholding Principal Orthogonal Complements
Fan, Jianqing; Liao, Yuan; Mincheva, Martina
2012-01-01
This paper deals with the estimation of a high-dimensional covariance with a conditional sparsity structure and fast-diverging eigenvalues. By assuming sparse error covariance matrix in an approximate factor model, we allow for the presence of some cross-sectional correlation even after taking out common but unobservable factors. We introduce the Principal Orthogonal complEment Thresholding (POET) method to explore such an approximate factor structure with sparsity. The POET estimator includes the sample covariance matrix, the factor-based covariance matrix (Fan, Fan, and Lv, 2008), the thresholding estimator (Bickel and Levina, 2008) and the adaptive thresholding estimator (Cai and Liu, 2011) as specific examples. We provide mathematical insights when the factor analysis is approximately the same as the principal component analysis for high-dimensional data. The rates of convergence of the sparse residual covariance matrix and the conditional sparse covariance matrix are studied under various norms. It is shown that the impact of estimating the unknown factors vanishes as the dimensionality increases. The uniform rates of convergence for the unobserved factors and their factor loadings are derived. The asymptotic results are also verified by extensive simulation studies. Finally, a real data application on portfolio allocation is presented. PMID:24348088
Combining orthogonal polarization for elongated target detection with GPR
International Nuclear Information System (INIS)
Lualdi, Maurizio; Lombardi, Federico
2014-01-01
For an accurate imaging of ground penetrating radar data the polarization characteristics of the propagating electromagnetic (EM) wavefield and wave amplitude variations with antenna pattern orientation must be taken into account. For objects that show some directionality feature and cylindrical shape any misalignment between transmitter and target can strongly modify the polarization state of the backscattered wavefield, thus conditioning the detection capability of the system. Hints on the depolarization can be used to design the optimal GPR antenna survey to avoid omissions and pitfalls during data processing. This research addresses the issue of elongated target detection through a multi azimuth (or multi polarization) approach based on the combination of mutually orthogonal GPR data. Results from the analysis of the formal scattering problem demonstrate how this strategy can reach a scalar formulation of the scattering matrix and achieve a rotational invariant quantity. The effectiveness of the algorithm is then evaluated with a detailed field example showing results closely proximal to those obtained under the optimal alignment condition: detection is significantly improved and the risk of target missing is reduced. (paper)
Statistical mechanics of learning orthogonal signals for general covariance models
International Nuclear Information System (INIS)
Hoyle, David C
2010-01-01
Statistical mechanics techniques have proved to be useful tools in quantifying the accuracy with which signal vectors are extracted from experimental data. However, analysis has previously been limited to specific model forms for the population covariance C, which may be inappropriate for real world data sets. In this paper we obtain new statistical mechanical results for a general population covariance matrix C. For data sets consisting of p sample points in R N we use the replica method to study the accuracy of orthogonal signal vectors estimated from the sample data. In the asymptotic limit of N,p→∞ at fixed α = p/N, we derive analytical results for the signal direction learning curves. In the asymptotic limit the learning curves follow a single universal form, each displaying a retarded learning transition. An explicit formula for the location of the retarded learning transition is obtained and we find marked variation in the location of the retarded learning transition dependent on the distribution of population covariance eigenvalues. The results of the replica analysis are confirmed against simulation
Large Covariance Estimation by Thresholding Principal Orthogonal Complements.
Fan, Jianqing; Liao, Yuan; Mincheva, Martina
2013-09-01
This paper deals with the estimation of a high-dimensional covariance with a conditional sparsity structure and fast-diverging eigenvalues. By assuming sparse error covariance matrix in an approximate factor model, we allow for the presence of some cross-sectional correlation even after taking out common but unobservable factors. We introduce the Principal Orthogonal complEment Thresholding (POET) method to explore such an approximate factor structure with sparsity. The POET estimator includes the sample covariance matrix, the factor-based covariance matrix (Fan, Fan, and Lv, 2008), the thresholding estimator (Bickel and Levina, 2008) and the adaptive thresholding estimator (Cai and Liu, 2011) as specific examples. We provide mathematical insights when the factor analysis is approximately the same as the principal component analysis for high-dimensional data. The rates of convergence of the sparse residual covariance matrix and the conditional sparse covariance matrix are studied under various norms. It is shown that the impact of estimating the unknown factors vanishes as the dimensionality increases. The uniform rates of convergence for the unobserved factors and their factor loadings are derived. The asymptotic results are also verified by extensive simulation studies. Finally, a real data application on portfolio allocation is presented.
Theory of direct sunlight transmission through orthogonal screen cells
International Nuclear Information System (INIS)
Aljofi, E.K.
2006-01-01
The Purpose of this paper is to investigate the feasibility of using the Rawshan screens to control high light intensity and to avoid excessive solar radiation penetrating inside the building interior. The exploration of the environmental characteristics of this device indicates an ideal solution to utilize available daylight in the arid atmosphere, reduces energy consumption due to the us of artificial light and ensures the continuity of the traditional architecture and the country heritage. A systematic analysis of direct sunlight transmission has been explored using a mathematical approach. The study intends to construct a predictive tool for the architects through which different specifications of the Rawshan screens were identified as far as direct beam of light concerned. The predictive tool was set-up to investigate various parameters of the screen such as the screen configurations, the aperture configurations, the change in orientation and the effect of the sky condition. The analysis of light transmission through the screen were set-up for orthogonal shapes
Babaee, Hessam; Choi, Minseok; Sapsis, Themistoklis P.; Karniadakis, George Em
2017-09-01
We develop a new robust methodology for the stochastic Navier-Stokes equations based on the dynamically-orthogonal (DO) and bi-orthogonal (BO) methods [1-3]. Both approaches are variants of a generalized Karhunen-Loève (KL) expansion in which both the stochastic coefficients and the spatial basis evolve according to system dynamics, hence, capturing the low-dimensional structure of the solution. The DO and BO formulations are mathematically equivalent [3], but they exhibit computationally complimentary properties. Specifically, the BO formulation may fail due to crossing of the eigenvalues of the covariance matrix, while both BO and DO become unstable when there is a high condition number of the covariance matrix or zero eigenvalues. To this end, we combine the two methods into a robust hybrid framework and in addition we employ a pseudo-inverse technique to invert the covariance matrix. The robustness of the proposed method stems from addressing the following issues in the DO/BO formulation: (i) eigenvalue crossing: we resolve the issue of eigenvalue crossing in the BO formulation by switching to the DO near eigenvalue crossing using the equivalence theorem and switching back to BO when the distance between eigenvalues is larger than a threshold value; (ii) ill-conditioned covariance matrix: we utilize a pseudo-inverse strategy to invert the covariance matrix; (iii) adaptivity: we utilize an adaptive strategy to add/remove modes to resolve the covariance matrix up to a threshold value. In particular, we introduce a soft-threshold criterion to allow the system to adapt to the newly added/removed mode and therefore avoid repetitive and unnecessary mode addition/removal. When the total variance approaches zero, we show that the DO/BO formulation becomes equivalent to the evolution equation of the Optimally Time-Dependent modes [4]. We demonstrate the capability of the proposed methodology with several numerical examples, namely (i) stochastic Burgers equation: we
Madl, Christopher M; Katz, Lily M; Heilshorn, Sarah C
2016-06-07
Covalently-crosslinked hydrogels are commonly used as 3D matrices for cell culture and transplantation. However, the crosslinking chemistries used to prepare these gels generally cross-react with functional groups present on the cell surface, potentially leading to cytotoxicity and other undesired effects. Bio-orthogonal chemistries have been developed that do not react with biologically relevant functional groups, thereby preventing these undesirable side reactions. However, previously developed biomaterials using these chemistries still possess less than ideal properties for cell encapsulation, such as slow gelation kinetics and limited tuning of matrix mechanics and biochemistry. Here, engineered elastin-like proteins (ELPs) are developed that cross-link via strain-promoted azide-alkyne cycloaddition (SPAAC) or Staudinger ligation. The SPAAC-crosslinked materials form gels within seconds and complete gelation within minutes. These hydrogels support the encapsulation and phenotypic maintenance of human mesenchymal stem cells, human umbilical vein endothelial cells, and murine neural progenitor cells. SPAAC-ELP gels exhibit independent tuning of stiffness and cell adhesion, with significantly improved cell viability and spreading observed in materials containing a fibronectin-derived arginine-glycine-aspartic acid (RGD) domain. The crosslinking chemistry used permits further material functionalization, even in the presence of cells and serum. These hydrogels are anticipated to be useful in a wide range of applications, including therapeutic cell delivery and bioprinting.
Scaffold Free Bio-orthogonal Assembly of 3-Dimensional Cardiac Tissue via Cell Surface Engineering
Rogozhnikov, Dmitry; O'Brien, Paul J.; Elahipanah, Sina; Yousaf, Muhammad N.
2016-12-01
There has been tremendous interest in constructing in vitro cardiac tissue for a range of fundamental studies of cardiac development and disease and as a commercial system to evaluate therapeutic drug discovery prioritization and toxicity. Although there has been progress towards studying 2-dimensional cardiac function in vitro, there remain challenging obstacles to generate rapid and efficient scaffold-free 3-dimensional multiple cell type co-culture cardiac tissue models. Herein, we develop a programmed rapid self-assembly strategy to induce specific and stable cell-cell contacts among multiple cell types found in heart tissue to generate 3D tissues through cell-surface engineering based on liposome delivery and fusion to display bio-orthogonal functional groups from cell membranes. We generate, for the first time, a scaffold free and stable self assembled 3 cell line co-culture 3D cardiac tissue model by assembling cardiomyocytes, endothelial cells and cardiac fibroblast cells via a rapid inter-cell click ligation process. We compare and analyze the function of the 3D cardiac tissue chips with 2D co-culture monolayers by assessing cardiac specific markers, electromechanical cell coupling, beating rates and evaluating drug toxicity.
Orthogonal use of a human tRNA synthetase active site to achieve multifunctionality.
Zhou, Quansheng; Kapoor, Mili; Guo, Min; Belani, Rajesh; Xu, Xiaoling; Kiosses, William B; Hanan, Melanie; Park, Chulho; Armour, Eva; Do, Minh-Ha; Nangle, Leslie A; Schimmel, Paul; Yang, Xiang-Lei
2010-01-01
Protein multifunctionality is an emerging explanation for the complexity of higher organisms. In this regard, aminoacyl tRNA synthetases catalyze amino acid activation for protein synthesis, but some also act in pathways for inflammation, angiogenesis and apoptosis. It is unclear how these multiple functions evolved and how they relate to the active site. Here structural modeling analysis, mutagenesis and cell-based functional studies show that the potent angiostatic, natural fragment of human tryptophanyl-tRNA synthetase (TrpRS) associates via tryptophan side chains that protrude from its cognate cellular receptor vascular endothelial cadherin (VE-cadherin). VE-cadherin's tryptophan side chains fit into the tryptophan-specific active site of the synthetase. Thus, specific side chains of the receptor mimic amino acid substrates and expand the functionality of the active site of the synthetase. We propose that orthogonal use of the same active site may be a general way to develop multifunctionality of human tRNA synthetases and other proteins.
Wang, Sai; Xu, Zuqiang; Wang, Tingting; Xiao, Tangxin; Hu, Xiao-Yu; Shen, Ying-Zhong; Wang, Leyong
2018-04-30
Functional materials play a vital role in the fabrication of smart windows, which can provide a more comfortable indoor environment for humans to enjoy a better lifestyle. Traditional materials for smart windows tend to possess only a single functionality with the purpose of regulating the input of solar energy. However, different color tones also have great influences on human emotions. Herein, a strategy for orthogonal integration of different properties is proposed, namely the thermo-responsiveness of ethylene glycol-modified pillar[6]arene (EGP6) and the redox-induced reversible color switching of ferrocene/ferrocenium groups are orthogonally integrated into one system. This gives rise to a material with cooperative and non-interfering dual functions, featuring both thermochromism and warm/cool tone-switchability. Consequently, the obtained bifunctional material for fabricating smart windows can not only regulate the input of solar energy but also can provide a more comfortable color tone to improve the feelings and emotions of people in indoor environments.
Elsheikh, Ahmed H.
2013-06-01
We introduce a nonlinear orthogonal matching pursuit (NOMP) for sparse calibration of subsurface flow models. Sparse calibration is a challenging problem as the unknowns are both the non-zero components of the solution and their associated weights. NOMP is a greedy algorithm that discovers at each iteration the most correlated basis function with the residual from a large pool of basis functions. The discovered basis (aka support) is augmented across the nonlinear iterations. Once a set of basis functions are selected, the solution is obtained by applying Tikhonov regularization. The proposed algorithm relies on stochastically approximated gradient using an iterative stochastic ensemble method (ISEM). In the current study, the search space is parameterized using an overcomplete dictionary of basis functions built using the K-SVD algorithm. The proposed algorithm is the first ensemble based algorithm that tackels the sparse nonlinear parameter estimation problem. © 2013 Elsevier Ltd.
Solution of the ratchet-shakedown Bree problem with an extra orthogonal primary load
International Nuclear Information System (INIS)
Bradford, R.A.W.
2015-01-01
The complete shakedown and ratcheting solution is derived analytically for a flat plate subject to unequal biaxial primary membrane stresses and a cyclic secondary bending stress in one in-plane direction (x). The Tresca yield condition and elastic-perfectly plastic behaviour are assumed. It is shown that the results can be expressed in the form of a “universal” ratchet diagram applicable for all magnitudes of orthogonal load. For sufficiently large cyclic bending stresses, tensile ratcheting can occur in the x direction if the x direction primary membrane stress exceeds half that in the orthogonal direction. Conversely, for sufficiently large cyclic bending stresses ratcheting in the x direction will be compressive if the x direction primary membrane stress is less than half that in the orthogonal direction. When the x direction primary membrane stress is exactly half that in the orthogonal direction ratcheting cannot occur however large the cyclic secondary bending stress. - Highlights: • A complete shakedown and ratcheting solution is derived analytically. • The problem is Bree-like but with an extra orthogonal primary load. • The ratchet diagram can be expressed in a form applicable to any orthogonal load. • Tensile ratcheting can occur if the primary load exceeds half the orthogonal load. • Compressive ratcheting can occur for smaller primary loads
Influence of mesh non-orthogonality on numerical simulation of buoyant jet flows
International Nuclear Information System (INIS)
Ishigaki, Masahiro; Abe, Satoshi; Sibamoto, Yasuteru; Yonomoto, Taisuke
2017-01-01
Highlights: • Influence of mesh non-orthogonality on numerical solution of buoyant jet flows. • Buoyant jet flows are simulated with hexahedral and prismatic meshes. • Jet instability with prismatic meshes may be overestimated compared to that with hexahedral meshes. • Modified solvers that can reduce the influence of mesh non-orthogonality and reduce computation time are proposed. - Abstract: In the present research, we discuss the influence of mesh non-orthogonality on numerical solution of a type of buoyant flow. Buoyant jet flows are simulated numerically with hexahedral and prismatic mesh elements in an open source Computational Fluid Dynamics (CFD) code called “OpenFOAM”. Buoyant jet instability obtained with the prismatic meshes may be overestimated compared to that obtained with the hexahedral meshes when non-orthogonal correction is not applied in the code. Although the non-orthogonal correction method can improve the instability generated by mesh non-orthogonality, it may increase computation time required to reach a convergent solution. Thus, we propose modified solvers that can reduce the influence of mesh non-orthogonality and reduce the computation time compared to the existing solvers in OpenFOAM. It is demonstrated that calculations for a buoyant jet with a large temperature difference are performed faster by the modified solver.
Influence of mesh non-orthogonality on numerical simulation of buoyant jet flows
Energy Technology Data Exchange (ETDEWEB)
Ishigaki, Masahiro, E-mail: ishigaki.masahiro@jaea.go.jp; Abe, Satoshi; Sibamoto, Yasuteru; Yonomoto, Taisuke
2017-04-01
Highlights: • Influence of mesh non-orthogonality on numerical solution of buoyant jet flows. • Buoyant jet flows are simulated with hexahedral and prismatic meshes. • Jet instability with prismatic meshes may be overestimated compared to that with hexahedral meshes. • Modified solvers that can reduce the influence of mesh non-orthogonality and reduce computation time are proposed. - Abstract: In the present research, we discuss the influence of mesh non-orthogonality on numerical solution of a type of buoyant flow. Buoyant jet flows are simulated numerically with hexahedral and prismatic mesh elements in an open source Computational Fluid Dynamics (CFD) code called “OpenFOAM”. Buoyant jet instability obtained with the prismatic meshes may be overestimated compared to that obtained with the hexahedral meshes when non-orthogonal correction is not applied in the code. Although the non-orthogonal correction method can improve the instability generated by mesh non-orthogonality, it may increase computation time required to reach a convergent solution. Thus, we propose modified solvers that can reduce the influence of mesh non-orthogonality and reduce the computation time compared to the existing solvers in OpenFOAM. It is demonstrated that calculations for a buoyant jet with a large temperature difference are performed faster by the modified solver.
Brachytherapy reconstruction using orthogonal scout views from the CT
International Nuclear Information System (INIS)
Perez, J.; Lliso, F.; Carmona, V.; Bea, J.; Tormo, A.; Petschen, I.
1996-01-01
Introduction: CT assisted brachytherapy planning is demonstrating to have great advantages as external RT planning does. One of the problems we have found in this approach with the conventional gynecological Fletcher applicators is the high amount of artefacts (ovoids with rectal and vessical protections) in the CT slice. We have introduced a reconstruction method based on scout views in order to avoid this problem, allowing us to perform brachytherapy reconstruction completely CT assisted. We use a virtual simulation chain by General Electric Medical Systems. Method and discussion: Two orthogonal scout views (0 and 90 tube positions) are performed. The reconstruction method takes into account the virtual position of the focus and the fact that there is only divergence in the transverse plane. Algorithms developed for sources as well as for reference points localisation (A, B, lymphatic Fletcher trapezoid, pelvic wall, etc.) are presented. This method has the following practical advantages: the porte-cassette is not necessary, the image quality can be improved (it is very helpful in pelvic lateral views that are critical in conventional radiographs), the total time to get the data is smaller than for conventional radiographs (reduction of patient motion effects) and problems that appear in CT-slice based reconstruction in the case of strongly curved intrauterine applicators are avoided. Even though the resolution is smaller than in conventional radiographs it is good enough for brachytherapy. Regarding the CT planning this method presents the interesting feature that the co-ordinate system is the same for the reconstruction process that for the CT-slices set. As the application can be reconstructed from scout views and the doses can be evaluated on CT slices it is easier to correlate the dose values obtained for the traditional points with those provided by the CT information
DEFF Research Database (Denmark)
Rasch, Astrid
of the collective, but insufficient attention has been paid to how individuals respond to such narrative changes. This dissertation examines the relationship between individual and collective memory at the end of empire through analysis of 13 end of empire autobiographies by public intellectuals from Australia......Decolonisation was a major event of the twentieth century, redrawing maps and impacting on identity narratives around the globe. As new nations defined their place in the world, the national and imperial past was retold in new cultural memories. These developments have been studied at the level......, the Anglophone Caribbean and Zimbabwe. I conceive of memory as reconstructive and social, with individual memory striving to make sense of the past in the present in dialogue with surrounding narratives. By examining recurring tropes in the autobiographies, like colonial education, journeys to the imperial...
International Nuclear Information System (INIS)
Guillemoles, A.; Lazareva, A.
2008-01-01
Gazprom is conquering the world. The Russian industrial giant owns the hugest gas reserves and enjoys the privilege of a considerable power. Gazprom edits journals, owns hospitals, airplanes and has even built cities where most of the habitants work for him. With 400000 workers, Gazprom represents 8% of Russia's GDP. This inquiry describes the history and operation of this empire and show how its has become a masterpiece of the government's strategy of russian influence reconquest at the world scale. Is it going to be a winning game? Are the corruption affairs and the expected depletion of resources going to weaken the empire? The authors shade light on the political and diplomatic strategies that are played around the crucial dossier of the energy supply. (J.S.)
Perera, Harsha N
2016-01-01
Considerable debate still exists among scholars over the role of trait emotional intelligence (TEI) in academic performance. The dominant theoretical position is that TEI should be orthogonal or only weakly related to achievement; yet, there are strong theoretical reasons to believe that TEI plays a key role in performance. The purpose of the current article is to provide (a) an overview of the possible theoretical mechanisms linking TEI with achievement and (b) an update on empirical research examining this relationship. To elucidate these theoretical mechanisms, the overview draws on multiple theories of emotion and regulation, including TEI theory, social-functional accounts of emotion, and expectancy-value and psychobiological model of emotion and regulation. Although these theoretical accounts variously emphasize different variables as focal constructs, when taken together, they provide a comprehensive picture of the possible mechanisms linking TEI with achievement. In this regard, the article redresses the problem of vaguely specified theoretical links currently hampering progress in the field. The article closes with a consideration of directions for future research.
Rahaman, Obaidur; Estrada, Trilce P; Doren, Douglas J; Taufer, Michela; Brooks, Charles L; Armen, Roger S
2011-09-26
The performances of several two-step scoring approaches for molecular docking were assessed for their ability to predict binding geometries and free energies. Two new scoring functions designed for "step 2 discrimination" were proposed and compared to our CHARMM implementation of the linear interaction energy (LIE) approach using the Generalized-Born with Molecular Volume (GBMV) implicit solvation model. A scoring function S1 was proposed by considering only "interacting" ligand atoms as the "effective size" of the ligand and extended to an empirical regression-based pair potential S2. The S1 and S2 scoring schemes were trained and 5-fold cross-validated on a diverse set of 259 protein-ligand complexes from the Ligand Protein Database (LPDB). The regression-based parameters for S1 and S2 also demonstrated reasonable transferability in the CSARdock 2010 benchmark using a new data set (NRC HiQ) of diverse protein-ligand complexes. The ability of the scoring functions to accurately predict ligand geometry was evaluated by calculating the discriminative power (DP) of the scoring functions to identify native poses. The parameters for the LIE scoring function with the optimal discriminative power (DP) for geometry (step 1 discrimination) were found to be very similar to the best-fit parameters for binding free energy over a large number of protein-ligand complexes (step 2 discrimination). Reasonable performance of the scoring functions in enrichment of active compounds in four different protein target classes established that the parameters for S1 and S2 provided reasonable accuracy and transferability. Additional analysis was performed to definitively separate scoring function performance from molecular weight effects. This analysis included the prediction of ligand binding efficiencies for a subset of the CSARdock NRC HiQ data set where the number of ligand heavy atoms ranged from 17 to 35. This range of ligand heavy atoms is where improved accuracy of predicted ligand
Energy Technology Data Exchange (ETDEWEB)
Barbaro, M. [ENEA, Centro Ricerche `Ezio Clementel`, Bologna (Italy). Dipt. Innovazione
1997-11-01
A numerical method is described which generates an orthogonal curvilinear mesh, subject to the constraint that mesh lines are matched to all boundaries of a closed, simply connected two-dimensional region of arbitrary shape. The method is based on the solution, by an iterative finite-difference technique, of an elliptic differential system of equations for the Cartesian coordinates of the orthogonal grid nodes. The interior grid distribution is controlled by a technique which ensures that coordinate lines can be concentrated as desired. Examples of orthogonal meshes inscribed in various geometrical figures are included.
Shamsudin, F.; Midden, C.J.H.
2007-01-01
In this study, we explore whether people’s worldviews are orthogonal. An orthogonal structure of worldviews was found from two independent studies in multi-cultural communities to be affected by a coal power plant technology. The two-dimensional worldview orientations were in rectangular(orthogonal)
Schweiner, Frank; Laturner, Jeanine; Main, Jörg; Wunner, Günter
2017-11-01
Until now only for specific crossovers between Poissonian statistics (P), the statistics of a Gaussian orthogonal ensemble (GOE), or the statistics of a Gaussian unitary ensemble (GUE) have analytical formulas for the level spacing distribution function been derived within random matrix theory. We investigate arbitrary crossovers in the triangle between all three statistics. To this aim we propose an according formula for the level spacing distribution function depending on two parameters. Comparing the behavior of our formula for the special cases of P→GUE, P→GOE, and GOE→GUE with the results from random matrix theory, we prove that these crossovers are described reasonably. Recent investigations by F. Schweiner et al. [Phys. Rev. E 95, 062205 (2017)2470-004510.1103/PhysRevE.95.062205] have shown that the Hamiltonian of magnetoexcitons in cubic semiconductors can exhibit all three statistics in dependence on the system parameters. Evaluating the numerical results for magnetoexcitons in dependence on the excitation energy and on a parameter connected with the cubic valence band structure and comparing the results with the formula proposed allows us to distinguish between regular and chaotic behavior as well as between existent or broken antiunitary symmetries. Increasing one of the two parameters, transitions between different crossovers, e.g., from the P→GOE to the P→GUE crossover, are observed and discussed.
Trade costs in empirical New Economic Geography
Bosker, E.M.; Garretsen, J.H.
Trade costs are a crucial element of New Economic Geography (NEG) models. Without trade costs there is no role for geography. In empirical NEG studies the unavailability of direct trade cost data calls for the need to approximate these trade costs by introducing a trade cost function. In doing so,
Alternative Approaches to Evaluation in Empirical Microeconomics
Blundell, Richard; Dias, Monica Costa
2009-01-01
This paper reviews some of the most popular policy evaluation methods in empirical microeconomics: social experiments, natural experiments, matching, instrumental variables, discontinuity design, and control functions. It discusses identification of traditionally used average parameters and more complex distributional parameters. The adequacy,…
Empirical scaling for present ohmic heated tokamaks
International Nuclear Information System (INIS)
Daughney, C.
1975-06-01
Empirical scaling laws are given for the average electron temperature and electron energy confinement time as functions of plasma current, average electron density, effective ion charge, toroidal magnetic field, and major and minor plasma radius. The ohmic heating is classical, and the electron energy transport is anomalous. The present scaling indicates that ohmic-heating becomes ineffective with larger experiments. (U.S.)
Empirical Differential Balancing for Nonlinear Systems
Kawano, Yu; Scherpen, Jacquelien M.A.; Dochain, Denis; Henrion, Didier; Peaucelle, Dimitri
In this paper, we consider empirical balancing of nonlinear systems by using its prolonged system, which consists of the original nonlinear system and its variational system. For the prolonged system, we define differential reachability and observability Gramians, which are matrix valued functions
Orthogonal Cas9 proteins for RNA-guided gene regulation and editing
Church, George M.; Esvelt, Kevin; Mali, Prashant
2017-03-07
Methods of modulating expression of a target nucleic acid in a cell are provided including use of multiple orthogonal Cas9 proteins to simultaneously and independently regulate corresponding genes or simultaneously and independently edit corresponding genes.
Gerrard, Simon R.; Hardiman, Claire; Shelbourne, Montserrat; Nandhakumar, Iris; Nordé n, Bengt; Brown, Tom
2012-01-01
chemistry for the synthesis of dimeric, trimeric, and oligomeric modular DNA scaffolds from cyclic, double-stranded, 80-mer DNA nanoconstructs. This particular combination of orthogonal click reactions was more effective for nanoassembly than others explored
Spin nematic and orthogonal nematic states in S=1 non-Heisenberg magnet
International Nuclear Information System (INIS)
Fridman, Yu.A.; Kosmachev, O.A.; Klevets, Ph.N.
2013-01-01
Phases of S=1 non-Heisenberg magnet at various relationships between the exchange integrals are studied in the mean-field limit at zero temperature. It is shown that four phases can be realized in the system under consideration: the ferromagnetic, antiferromagnetic, nematic, and the orthogonal nematic states. The phase diagram is constructed. It is shown that the phase transitions between the ferromagnetic phase and the orthogonal nematic phase and between the antiferromagnetic phase and the orthogonal nematic phase are the degenerated first-order transitions. For the first time the spectra of elementary excitations in all phases are obtained within the mean-field limit. - Highlights: ► We investigated phases of S=1 non-Heisenberg magnet. ► Found four phases: ferromagnetic, antiferromagnetic, nematic, and orthogonal nematic. ► The phase diagram is determined. ► The spectra of elementary excitations are obtained in all phases for the first time.
Lindeboom, Jerome A.; Mathura, Keshen R.; Ince, Can
2006-01-01
Tumor microcirculatory characteristics until now have only been assessed by histological examination of biopsies or invasive imaging technique. The recent introduction of orthogonal polarization spectral (OPS) imaging as a new tool for in vivo visualization of human microcirculation makes it
On the 2-orthogonal polynomials and the generalized birth and death processes
Directory of Open Access Journals (Sweden)
Zerouki Ebtissem
2006-01-01
Full Text Available We discuss the connections between the 2-orthogonal polynomials and the generalized birth and death processes. Afterwards, we find the sufficient conditions to give an integral representation of the transition probabilities from these processes.
A Comparative Study for Orthogonal Subspace Projection and Constrained Energy Minimization
National Research Council Canada - National Science Library
Du, Qian; Ren, Hsuan; Chang, Chein-I
2003-01-01
...: orthogonal subspace projection (OSP) and constrained energy minimization (CEM). It is shown that they are closely related and essentially equivalent provided that the noise is white with large SNR...
Volume-of-fluid algorithm on a non-orthogonal grid
International Nuclear Information System (INIS)
Jang, W.; Lien, F.S.; Ji, H.
2005-01-01
In the present study, a novel VOF method on a non-orthogonal grid is proposed and tested for several benchmark problems, including a simple translation test, a reversed single vortex flow and a shearing flow, with the objective to demonstrate the feasibility and accuracy of the present approach. Excellent agreement between the solutions obtained on both orthogonal and non-orthogonal meshes is achieved. The sensitivity of various methods to the L 1 error in evaluating the interface normal and volume flux at each face of a non-orthogonal cell is examined. Time integration methods based on the operator-splitting approach in curvilinear coordinates, including the explicit-implicit (EX-IM) and explicit-explicit (EX-EX) combinations, are tested. (author)
van den Oever, Huub L. A.; Dzoljic, Misa; Ince, Can; Hollmann, Markus W.; Mokken, Fleur C.
2006-01-01
We used Orthogonal Polarization Spectral Imaging to examine the microcirculation of the vaginal mucosa in nine anesthetized patients during two consecutive anesthetic interventions: hypervolemic hemodilution using hydroxyethyl starch followed by thoracic epidural lidocaine. Images taken before and
Hofer, Marlis; MöLg, Thomas; Marzeion, Ben; Kaser, Georg
2010-06-01
Recently initiated observation networks in the Cordillera Blanca (Peru) provide temporally high-resolution, yet short-term, atmospheric data. The aim of this study is to extend the existing time series into the past. We present an empirical-statistical downscaling (ESD) model that links 6-hourly National Centers for Environmental Prediction (NCEP)/National Center for Atmospheric Research (NCAR) reanalysis data to air temperature and specific humidity, measured at the tropical glacier Artesonraju (northern Cordillera Blanca). The ESD modeling procedure includes combined empirical orthogonal function and multiple regression analyses and a double cross-validation scheme for model evaluation. Apart from the selection of predictor fields, the modeling procedure is automated and does not include subjective choices. We assess the ESD model sensitivity to the predictor choice using both single-field and mixed-field predictors. Statistical transfer functions are derived individually for different months and times of day. The forecast skill largely depends on month and time of day, ranging from 0 to 0.8. The mixed-field predictors perform better than the single-field predictors. The ESD model shows added value, at all time scales, against simpler reference models (e.g., the direct use of reanalysis grid point values). The ESD model forecast 1960-2008 clearly reflects interannual variability related to the El Niño/Southern Oscillation but is sensitive to the chosen predictor type.
Orthogonal translation components for the in vivo incorporation of unnatural amino acids
Schultz, Peter G.; Xie, Jianming; Zeng, Huaqiang
2012-07-10
The invention relates to orthogonal pairs of tRNAs and aminoacyl-tRNA synthetases that can incorporate unnatural amino acids into proteins produced in eubacterial host cells such as E. coli, or in a eukaryotic host such as a yeast cell. The invention provides, for example but not limited to, novel orthogonal synthetases, methods for identifying and making the novel synthetases, methods for producing proteins containing unnatural amino acids, and translation systems.
Performance of an Orthogonal Multicarrier CDMA System in a Multicell/Multipath Environment
Energy Technology Data Exchange (ETDEWEB)
Yoon, W.S. [Ajou University, Suwon (Korea)
1999-08-01
We have considered an improved orthogonal multicarrier (MC) CDMA system. This system combines the advantages of both DS-CDMA with a concatenated spreading scheme and an MC modulation technique to combat the effects of a multipath fading channel and intersymbol interference (IS). The performance of the system is analyzed under a multicell, multiuser, and multipath Rician fading channel. The system is shown to outperform the orthogonal MC-CDMA system with a conventional PN sequence. (author). 4 refs., 3 figs.
Image compression based on orthogonal balanced multiwavelets with symmetry/antisymmetry
Zhang, Liping; Zhao, Yi
2018-03-01
Multiwavelets have orthogonality, compacted support and symmetry simultaneously, these properties are very important for signal processing. However, most of Multiwavelets require related prefilters. An approach to construction of symmetry/antisymmetry orthogonal filter is proposed and its corresponding balanced filter is constructed, no any prefilter is necessary. Experimental results prove its performance is superior to DGHM and CL multiwavelets, higher than Bi9/7.
Amplitude Noise Suppression and Orthogonal Multiplexing Using Injection-Locked Single-Mode VCSEL
DEFF Research Database (Denmark)
Lyubopytov, Vladimir; von Lerber, Tuomo; Lassas, Matti
2017-01-01
We experimentally demonstrate BER reduction and orthogonal modulation using an injection locked single-mode VCSEL. It allows us suppressing an amplitude noise of optical signal and/or double the capacity of an information channel.......We experimentally demonstrate BER reduction and orthogonal modulation using an injection locked single-mode VCSEL. It allows us suppressing an amplitude noise of optical signal and/or double the capacity of an information channel....
International Nuclear Information System (INIS)
Yahiaoui, S.-A.; Bentaiba, M.
2011-01-01
We present a method for obtaining the quasi-exact solutions of the Rabi Hamiltonian in the framework of the asymptotic iteration method (AIM). The energy eigenvalues, the eigenfunctions and the associated Bender-Dunne orthogonal polynomials are deduced. We show (i) that orthogonal polynomials are generated from the upper limit (i.e., truncation limit) of polynomial solutions deduced from AIM, and (ii) prove to have nonpositive norm. (authors)
Epistemology and Empirical Investigation
DEFF Research Database (Denmark)
Ahlström, Kristoffer
2008-01-01
Recently, Hilary Kornblith has argued that epistemological investigation is substantially empirical. In the present paper, I will ¿rst show that his claim is not contingent upon the further and, admittedly, controversial assumption that all objects of epistemological investigation are natural kinds....... Then, I will argue that, contrary to what Kornblith seems to assume, this methodological contention does not imply that there is no need for attending to our epistemic concepts in epistemology. Understanding the make-up of our concepts and, in particular, the purposes they ¿ll, is necessary...
Orthogonal Multi-Carrier DS-CDMA with Frequency-Domain Equalization
Tanaka, Ken; Tomeba, Hiromichi; Adachi, Fumiyuki
Orthogonal multi-carrier direct sequence code division multiple access (orthogonal MC DS-CDMA) is a combination of orthogonal frequency division multiplexing (OFDM) and time-domain spreading, while multi-carrier code division multiple access (MC-CDMA) is a combination of OFDM and frequency-domain spreading. In MC-CDMA, a good bit error rate (BER) performance can be achieved by using frequency-domain equalization (FDE), since the frequency diversity gain is obtained. On the other hand, the conventional orthogonal MC DS-CDMA fails to achieve any frequency diversity gain. In this paper, we propose a new orthogonal MC DS-CDMA that can obtain the frequency diversity gain by applying FDE. The conditional BER analysis is presented. The theoretical average BER performance in a frequency-selective Rayleigh fading channel is evaluated by the Monte-Carlo numerical computation method using the derived conditional BER and is confirmed by computer simulation of the orthogonal MC DS-CDMA signal transmission.
Directory of Open Access Journals (Sweden)
Moret Nicola
2010-01-01
Full Text Available Abstract We address the efficient realization of a filtered multitone (FMT modulation system and its orthogonal design. FMT modulation can be viewed as a Discrete Fourier Transform (DFT modulated filter bank (FB. It generalizes the popular orthogonal frequency division multiplexing (OFDM scheme by deploying frequency confined subchannel pulses. We compare three realizations that have been described by Cvetković and Vetterli (1998, and Weiss and Stewart (2000, and Tonello (2006. A detailed derivation of them is performed in the time-domain via the exploitation of different FB polyphase decompositions. We then consider the design of an orthogonal FMT system and we exploit the third realization which allows simplifying the orthogonal FB design and obtaining a block diagonal system matrix with independent subblocks. A numerical method is then presented to obtain an orthogonal FB with well frequency confined subchannel pulses for arbitrarily large number of subchannels. Several examples of pulses with minimal length are reported and their performance is evaluated in typical multipath fading channels. Finally, we compare the orthogonal FMT system with a cyclically prefixed OFDM system in the IEEE 802.11 wireless LAN channel. In this scenario, FMT with minimal length pulses and single tap subchannel equalization outperforms the OFDM system in achievable rate.
Directory of Open Access Journals (Sweden)
Andrea M. Tonello
2010-01-01
Full Text Available We address the efficient realization of a filtered multitone (FMT modulation system and its orthogonal design. FMT modulation can be viewed as a Discrete Fourier Transform (DFT modulated filter bank (FB. It generalizes the popular orthogonal frequency division multiplexing (OFDM scheme by deploying frequency confined subchannel pulses. We compare three realizations that have been described by Cvetković and Vetterli (1998, and Weiss and Stewart (2000, and Tonello (2006. A detailed derivation of them is performed in the time-domain via the exploitation of different FB polyphase decompositions. We then consider the design of an orthogonal FMT system and we exploit the third realization which allows simplifying the orthogonal FB design and obtaining a block diagonal system matrix with independent subblocks. A numerical method is then presented to obtain an orthogonal FB with well frequency confined subchannel pulses for arbitrarily large number of subchannels. Several examples of pulses with minimal length are reported and their performance is evaluated in typical multipath fading channels. Finally, we compare the orthogonal FMT system with a cyclically prefixed OFDM system in the IEEE 802.11 wireless LAN channel. In this scenario, FMT with minimal length pulses and single tap subchannel equalization outperforms the OFDM system in achievable rate.
Moret, Nicola; Tonello, Andrea M.
2010-12-01
We address the efficient realization of a filtered multitone (FMT) modulation system and its orthogonal design. FMT modulation can be viewed as a Discrete Fourier Transform (DFT) modulated filter bank (FB). It generalizes the popular orthogonal frequency division multiplexing (OFDM) scheme by deploying frequency confined subchannel pulses. We compare three realizations that have been described by Cvetković and Vetterli (1998), and Weiss and Stewart (2000), and Tonello (2006). A detailed derivation of them is performed in the time-domain via the exploitation of different FB polyphase decompositions. We then consider the design of an orthogonal FMT system and we exploit the third realization which allows simplifying the orthogonal FB design and obtaining a block diagonal system matrix with independent subblocks. A numerical method is then presented to obtain an orthogonal FB with well frequency confined subchannel pulses for arbitrarily large number of subchannels. Several examples of pulses with minimal length are reported and their performance is evaluated in typical multipath fading channels. Finally, we compare the orthogonal FMT system with a cyclically prefixed OFDM system in the IEEE 802.11 wireless LAN channel. In this scenario, FMT with minimal length pulses and single tap subchannel equalization outperforms the OFDM system in achievable rate.
International Nuclear Information System (INIS)
Bianchini, Alessandro; Balduzzi, Francesco; Ferrara, Giovanni; Ferrari, Lorenzo
2016-01-01
Highlights: • New method to calculate the incidence angle from a computed CFD flow field. • Applicable to each airfoil rotating around an axis orthogonal to flow direction. • Composed by four, easily automatable steps explained in details. • Robustness of the model assessed on two Darrieus turbine study cases. - Abstract: Numerical simulations provided in the last few years a significant contribution for a better understanding of many phenomena connected to the flow past rotating blades. In case of airfoils rotating around an axis orthogonal to flow direction, one of the most critical issues is represented by the definition of the incidence angle on the airfoil from the computed flow field. Incidence indeed changes continuously as a function of the azimuthal position of the blade and a distribution of peripheral speed is experienced along the airfoil’s thickness due to radius variation. The possibility of reducing the flow to lumped parameters (relative speed modulus and direction), however, would be of capital relevance to transpose accurate CFD numerical results into effective inputs to low-order models that are often exploited for preliminary design analyses. If several techniques are available for this scope in the case of blades rotating around an axis parallel to flow direction (e.g., horizontal-axis wind turbines), the definition of a robust procedure in case the revolution axis is orthogonal to the flow is still missing. In the study, a novel technique has been developed using data from Darrieus-like rotating airfoils. The method makes use of the virtual camber theory to define a virtual airfoil whose pressure coefficient distributions in straight flow are used to match those of the real airfoil in curved flow. Even if developed originally for vertical-axis wind turbines, the method is of general validity and is thought to represent in the near future a valuable tool for researchers to get a new insight on many complex phenomena connected to flow
Numerical modelling of orthogonal cutting: application to woodworking with a bench plane.
Nairn, John A
2016-06-06
A numerical model for orthogonal cutting using the material point method was applied to woodcutting using a bench plane. The cutting process was modelled by accounting for surface energy associated with wood fracture toughness for crack growth parallel to the grain. By using damping to deal with dynamic crack propagation and modelling all contact between wood and the plane, simulations could initiate chip formation and proceed into steady-state chip propagation including chip curling. Once steady-state conditions were achieved, the cutting forces became constant and could be determined as a function of various simulation variables. The modelling details included a cutting tool, the tool's rake and grinding angles, a chip breaker, a base plate and a mouth opening between the base plate and the tool. The wood was modelled as an anisotropic elastic-plastic material. The simulations were verified by comparison to an analytical model and then used to conduct virtual experiments on wood planing. The virtual experiments showed interactions between depth of cut, chip breaker location and mouth opening. Additional simulations investigated the role of tool grinding angle, tool sharpness and friction.
Application of the Proper Orthogonal Decomposition to Turbulent Czochralski Convective Flows
International Nuclear Information System (INIS)
Rahal, S; Cerisier, P; Azuma, H
2007-01-01
The aim of this work is to study the general aspects of the convective flow instabilities in a simulated Czochralski system. We considered the influence of the buoyancy and crystal rotation. Velocity fields, obtained by an ultrasonic technique, the corresponding 2D Fourier spectra and a correlation function, have been used. Steady, quasi-periodic and turbulent flows, are successively recognized, as the Reynolds number was increased, for a fixed Rayleigh number. The orthogonal decomposition method was applied and the numbers of modes, involved in the dynamics of turbulent flows, calculated. As far as we know, this method has been used for the first time to study the Czochralski convective flows. This method provides also information on the most important modes and allows simple theoretical models to be established. The large rotation rates of the crystal were found to stabilize the flow, and conversely the temperature gradients destabilize the flow. Indeed, the increase of the rotation effects reduces the number of involved modes and oscillations, and conversely, as expected, the increase of the buoyancy effects induces more modes to be involved in the dynamics. Thus, the flow oscillations can be reduced either by increasing the crystal rotation rate to the adequate value, as shown in this study or by imposing a magnetic field
Bonnice, W. F.; Motyka, P.; Wagner, E.; Hall, S. R.
1986-01-01
The performance of the orthogonal series generalized likelihood ratio (OSGLR) test in detecting and isolating commercial aircraft control surface and actuator failures is evaluated. A modification to incorporate age-weighting which significantly reduces the sensitivity of the algorithm to modeling errors is presented. The steady-state implementation of the algorithm based on a single linear model valid for a cruise flight condition is tested using a nonlinear aircraft simulation. A number of off-nominal no-failure flight conditions including maneuvers, nonzero flap deflections, different turbulence levels and steady winds were tested. Based on the no-failure decision functions produced by off-nominal flight conditions, the failure detection and isolation performance at the nominal flight condition was determined. The extension of the algorithm to a wider flight envelope by scheduling on dynamic pressure and flap deflection is examined. Based on this testing, the OSGLR algorithm should be capable of detecting control surface failures that would affect the safe operation of a commercial aircraft. Isolation may be difficult if there are several surfaces which produce similar effects on the aircraft. Extending the algorithm over the entire operating envelope of a commercial aircraft appears feasible.
Radiotherapy of ovarian epithelial cancer by total orthogonal field irradiation of the abdomen
International Nuclear Information System (INIS)
Delouche, G.; Valinta, D.; Bachelot, F.
1981-01-01
Isotopic intraperitoneal curietherapy by 32 P is the simplest method for irradiating the peritoneum, but it has only limited indications. This irradiation has usually to be given by the percutaneous route, but because of the size of the region to be irradiated it raises delicate problems poorly resolved by the traditional methods applied. For this reason, a particular method is suggested including, among other characteristics: 4 orthogonal fields; 2 sessions daily, irradiating one part of the abdomen in the morning and the other part in the afternoon; spreading of the doses in confirmity with current specifications; and modulation of the total dose as a function of the maximum size of the tumoral remnants. Abdominal radiotherapy is currently the method of choice in cases where lesions are in their early stages, in so far as chemotherapy, much more restrictive for the patient, has not yet demonstrated its long-term efficacy. A controlled clinical study is necessary in order to determine the most effective method [fr
Directory of Open Access Journals (Sweden)
Goran N. Jovanovic
2007-01-01
Full Text Available Lack of specificity for different classes of chemical and biological agents, and false positives and negatives, can limit the range of applications for cell-based biosensors. This study suggests that the integration of results from algal cells (Mesotaenium caldariorum and fish chromatophores (Betta splendens improves classification efficiency and detection reliability. Cells were challenged with paraquat, mercuric chloride, sodium arsenite and clonidine. The two detection systems were independently investigated for classification of the toxin set by performing discriminant analysis. The algal system correctly classified 72% of the bioactive compounds, whereas the fish chromatophore system correctly classified 68%. The combined classification efficiency was 95%. The algal sensor readout is based on fluorescence measurements of changes in the energy producing pathways of photosynthetic cells, whereas the response from fish chromatophores was quantified using optical density. Change in optical density reflects interference with the functioning of cellular signal transduction networks. Thus, algal cells and fish chromatophores respond to the challenge agents through sufficiently different mechanisms of action to be considered orthogonal.
Synthetic strategies for plant signalling studies: molecular toolbox and orthogonal platforms
Braguy, Justine
2016-05-26
Plants deploy a wide array of signalling networks integrating environmental cues with growth, defence and developmental responses. The high level of complexity, redundancy and connection between several pathways hampers a comprehensive understanding of involved functional and regulatory mechanisms. The implementation of synthetic biology approaches is revolutionizing experimental biology in prokaryotes, yeasts and animal systems and can likewise contribute to a new era in plant biology. This review gives an overview on synthetic biology approaches for the development and implementation of synthetic molecular tools and techniques to interrogate, understand and control signalling events in plants, ranging from strategies for the targeted manipulation of plant genomes up to the spatiotemporally resolved control of gene expression using optogenetic approaches. We also describe strategies based on the partial reconstruction of signalling pathways in orthogonal platforms, like yeast, animal and in vitro systems. This allows a targeted analysis of individual signalling hubs devoid of inter-connectivity with endogenous interacting components. Implementation of the interdisciplinary synthetic biology tools and strategies is not exempt of challenges and hardships but simultaneously most rewarding in terms of the advances in basic and applied research. As witnessed in other areas, these original theoretical-experimental avenues will lead to a breakthrough in the ability to study and comprehend plant signalling networks. This article is protected by copyright. All rights reserved.
What 'empirical turn in bioethics'?
Hurst, Samia
2010-10-01
Uncertainty as to how we should articulate empirical data and normative reasoning seems to underlie most difficulties regarding the 'empirical turn' in bioethics. This article examines three different ways in which we could understand 'empirical turn'. Using real facts in normative reasoning is trivial and would not represent a 'turn'. Becoming an empirical discipline through a shift to the social and neurosciences would be a turn away from normative thinking, which we should not take. Conducting empirical research to inform normative reasoning is the usual meaning given to the term 'empirical turn'. In this sense, however, the turn is incomplete. Bioethics has imported methodological tools from empirical disciplines, but too often it has not imported the standards to which researchers in these disciplines are held. Integrating empirical and normative approaches also represents true added difficulties. Addressing these issues from the standpoint of debates on the fact-value distinction can cloud very real methodological concerns by displacing the debate to a level of abstraction where they need not be apparent. Ideally, empirical research in bioethics should meet standards for empirical and normative validity similar to those used in the source disciplines for these methods, and articulate these aspects clearly and appropriately. More modestly, criteria to ensure that none of these standards are completely left aside would improve the quality of empirical bioethics research and partly clear the air of critiques addressing its theoretical justification, when its rigour in the particularly difficult context of interdisciplinarity is what should be at stake.
Directory of Open Access Journals (Sweden)
Maria Gabriela Campolina Diniz Peixoto
2014-05-01
Full Text Available The objective of this work was to compare random regression models for the estimation of genetic parameters for Guzerat milk production, using orthogonal Legendre polynomials. Records (20,524 of test-day milk yield (TDMY from 2,816 first-lactation Guzerat cows were used. TDMY grouped into 10-monthly classes were analyzed for additive genetic effect and for environmental and residual permanent effects (random effects, whereas the contemporary group, calving age (linear and quadratic effects and mean lactation curve were analized as fixed effects. Trajectories for the additive genetic and permanent environmental effects were modeled by means of a covariance function employing orthogonal Legendre polynomials ranging from the second to the fifth order. Residual variances were considered in one, four, six, or ten variance classes. The best model had six residual variance classes. The heritability estimates for the TDMY records varied from 0.19 to 0.32. The random regression model that used a second-order Legendre polynomial for the additive genetic effect, and a fifth-order polynomial for the permanent environmental effect is adequate for comparison by the main employed criteria. The model with a second-order Legendre polynomial for the additive genetic effect, and that with a fourth-order for the permanent environmental effect could also be employed in these analyses.
EGG: Empirical Galaxy Generator
Schreiber, C.; Elbaz, D.; Pannella, M.; Merlin, E.; Castellano, M.; Fontana, A.; Bourne, N.; Boutsia, K.; Cullen, F.; Dunlop, J.; Ferguson, H. C.; MichaÅowski, M. J.; Okumura, K.; Santini, P.; Shu, X. W.; Wang, T.; White, C.
2018-04-01
The Empirical Galaxy Generator (EGG) generates fake galaxy catalogs and images with realistic positions, morphologies and fluxes from the far-ultraviolet to the far-infrared. The catalogs are generated by egg-gencat and stored in binary FITS tables (column oriented). Another program, egg-2skymaker, is used to convert the generated catalog into ASCII tables suitable for ingestion by SkyMaker (ascl:1010.066) to produce realistic high resolution images (e.g., Hubble-like), while egg-gennoise and egg-genmap can be used to generate the low resolution images (e.g., Herschel-like). These tools can be used to test source extraction codes, or to evaluate the reliability of any map-based science (stacking, dropout identification, etc.).
Daul, Claude
2014-09-01
Despite the important growth of ab initio and computational techniques, ligand field theory in molecular science or crystal field theory in condensed matter offers the most intuitive way to calculate multiplet energy levels arising from systems with open shells d and/or f electrons. Over the past decade we have developed a ligand field treatment of inorganic molecular modelling taking advantage of the dominant localization of the frontier orbitals within the metal-sphere. This feature, which is observed in any inorganic coordination compound, especially if treated by Density Functional Theory calculation, allows the determination of the electronic structure and properties with a surprising good accuracy. In ligand field theory, the theoretical concepts consider only a single atom center; and treat its interaction with the chemical environment essentially as a perturbation. Therefore success in the simple ligand field theory is no longer questionable, while the more accurate molecular orbital theory does in general over-estimate the metal-ligand covalence, thus yields wave functions that are too delocalized. Although LF theory has always been popular as a semi-empirical method when dealing with molecules of high symmetry e.g. cubic symmetry where the number of parameters needed is reasonably small (3 or 5), this is no more the case for molecules without symmetry and involving both an open d- and f-shell (# parameters ∼90). However, the combination of LF theory and Density Functional (DF) theory that we introduced twenty years ago can easily deal with complex molecules of any symmetry with two and more open shells. The accuracy of these predictions from 1(st) principles achieves quite a high accuracy (<5%) in terms of states energies. Hence, this approach is well suited to predict the magnetic and photo-physical properties arbitrary molecules and materials prior to their synthesis, which is the ultimate goal of each computational chemist. We will illustrate the
International Nuclear Information System (INIS)
Oakdale, James S.; Kwisnek, Luke; Fokin, Valery V.
2016-01-01
Functional polystyrenes and polyacrylamides, containing combinations of fluorosulfate, aromatic silyl ether, and azide side chains, were used as scaffolds to demonstrate the postpolymerization modification capabilities of sulfur(VI) fluoride exchange (SuFEx) and CuAAC chemistries. Fluorescent dyes bearing appropriate functional groups were sequentially attached to the backbone of the copolymers, quantitatively and selectively addressing their reactive partners. Furthermore, this combined SuFEx and CuAAC approach proved to be robust and versatile, allowing for a rare accomplishment: triple orthogonal functionalization of a copolymer under essentially ambient conditions without protecting groups.
Volkov, R. S.; Zabelin, M. V.; Kuznetsov, G. V.; Strizhak, P. A.
2016-07-01
An experimental study has been made of the influence of an orthogonal (side) air flow propagating with a velocity to 5 m/s on the phases of transformation of a water slug with an initial volume of 0.05-0.5 liter in free fall from a height of 3 m. Use was made of Phantom V411 and Phantom Miro M310 high-speed video cameras and a Tema Automotive software system with the function of continuous tracking. The laws of retardation of the phases of transformation of the water slug from the instant of formation to that of formation of a droplet cloud under the action of the air flow orthogonal to the direction of the slug motion, and also of the deceleration, removal, and destruction of the droplets and fragments of water separating from the slug surface, have been established.
Numerical schemes for dynamically orthogonal equations of stochastic fluid and ocean flows
International Nuclear Information System (INIS)
Ueckermann, M.P.; Lermusiaux, P.F.J.; Sapsis, T.P.
2013-01-01
The quantification of uncertainties is critical when systems are nonlinear and have uncertain terms in their governing equations or are constrained by limited knowledge of initial and boundary conditions. Such situations are common in multiscale, intermittent and non-homogeneous fluid and ocean flows. The dynamically orthogonal (DO) field equations provide an adaptive methodology to predict the probability density functions of such flows. The present work derives efficient computational schemes for the DO methodology applied to unsteady stochastic Navier–Stokes and Boussinesq equations, and illustrates and studies the numerical aspects of these schemes. Semi-implicit projection methods are developed for the mean and for the DO modes, and time-marching schemes of first to fourth order are used for the stochastic coefficients. Conservative second-order finite-volumes are employed in physical space with new advection schemes based on total variation diminishing methods. Other results include: (i) the definition of pseudo-stochastic pressures to obtain a number of pressure equations that is linear in the subspace size instead of quadratic; (ii) symmetric advection schemes for the stochastic velocities; (iii) the use of generalized inversion to deal with singular subspace covariances or deterministic modes; and (iv) schemes to maintain orthonormal modes at the numerical level. To verify our implementation and study the properties of our schemes and their variations, a set of stochastic flow benchmarks are defined including asymmetric Dirac and symmetric lock-exchange flows, lid-driven cavity flows, and flows past objects in a confined channel. Different Reynolds number and Grashof number regimes are employed to illustrate robustness. Optimal convergence under both time and space refinements is shown as well as the convergence of the probability density functions with the number of stochastic realizations.
Zhang, Guoqing; Sun, Huaijiang; Xia, Guiyu; Sun, Quansen
2016-07-07
Sparse representation based classification (SRC) has been developed and shown great potential for real-world application. Based on SRC, Yang et al. [10] devised a SRC steered discriminative projection (SRC-DP) method. However, as a linear algorithm, SRC-DP cannot handle the data with highly nonlinear distribution. Kernel sparse representation-based classifier (KSRC) is a non-linear extension of SRC and can remedy the drawback of SRC. KSRC requires the use of a predetermined kernel function and selection of the kernel function and its parameters is difficult. Recently, multiple kernel learning for SRC (MKL-SRC) [22] has been proposed to learn a kernel from a set of base kernels. However, MKL-SRC only considers the within-class reconstruction residual while ignoring the between-class relationship, when learning the kernel weights. In this paper, we propose a novel multiple kernel sparse representation-based classifier (MKSRC), and then we use it as a criterion to design a multiple kernel sparse representation based orthogonal discriminative projection method (MK-SR-ODP). The proposed algorithm aims at learning a projection matrix and a corresponding kernel from the given base kernels such that in the low dimension subspace the between-class reconstruction residual is maximized and the within-class reconstruction residual is minimized. Furthermore, to achieve a minimum overall loss by performing recognition in the learned low-dimensional subspace, we introduce cost information into the dimensionality reduction method. The solutions for the proposed method can be efficiently found based on trace ratio optimization method [33]. Extensive experimental results demonstrate the superiority of the proposed algorithm when compared with the state-of-the-art methods.
Eugene N. Anderson
2016-01-01
The Mongol Empire, the largest contiguous empire the world has ever known, had, among other things, a goodly number of falconers, poultry raisers, birdcatchers, cooks, and other experts on various aspects of birding. We have records of this, largely in the Yinshan Zhengyao, the court nutrition manual of the Mongol empire in China (the Yuan Dynasty). It discusses in some detail 22 bird taxa, from swans to chickens. The Huihui Yaofang, a medical encyclopedia, lists ten taxa used medicinally. Ma...
Directory of Open Access Journals (Sweden)
Masjed-Jamei Mohammad
2005-01-01
Full Text Available From the main equation ( a x 2 +bx+c y ″ n ( x +( dx+e y ′ n ( x −n( ( n−1 a+d y n ( x =0 , n∈ ℤ + , six finite and infinite classes of orthogonal polynomials can be extracted. In this work, first we have a survey on these classes, particularly on finite classes, and their corresponding rational orthogonal polynomials, which are generated by Mobius transform x=p z −1 +q , p≠0 , q∈ℝ . Some new integral relations are also given in this section for the Jacobi, Laguerre, and Bessel orthogonal polynomials. Then we show that the rational orthogonal polynomials can be a very suitable tool to compute the inverse Laplace transform directly, with no additional calculation for finding their roots. In this way, by applying infinite and finite rational classical orthogonal polynomials, we give three basic expansions of six ones as a sample for computation of inverse Laplace transform.
New Empirical Earthquake Source‐Scaling Laws
Thingbaijam, Kiran Kumar S.
2017-12-13
We develop new empirical scaling laws for rupture width W, rupture length L, rupture area A, and average slip D, based on a large database of rupture models. The database incorporates recent earthquake source models in a wide magnitude range (M 5.4–9.2) and events of various faulting styles. We apply general orthogonal regression, instead of ordinary least-squares regression, to account for measurement errors of all variables and to obtain mutually self-consistent relationships. We observe that L grows more rapidly with M compared to W. The fault-aspect ratio (L/W) tends to increase with fault dip, which generally increases from reverse-faulting, to normal-faulting, to strike-slip events. At the same time, subduction-inter-face earthquakes have significantly higher W (hence a larger rupture area A) compared to other faulting regimes. For strike-slip events, the growth of W with M is strongly inhibited, whereas the scaling of L agrees with the L-model behavior (D correlated with L). However, at a regional scale for which seismogenic depth is essentially fixed, the scaling behavior corresponds to the W model (D not correlated with L). Self-similar scaling behavior with M − log A is observed to be consistent for all the cases, except for normal-faulting events. Interestingly, the ratio D/W (a proxy for average stress drop) tends to increase with M, except for shallow crustal reverse-faulting events, suggesting the possibility of scale-dependent stress drop. The observed variations in source-scaling properties for different faulting regimes can be interpreted in terms of geological and seismological factors. We find substantial differences between our new scaling relationships and those of previous studies. Therefore, our study provides critical updates on source-scaling relations needed in seismic–tsunami-hazard analysis and engineering applications.
Empirical techniques in finance
Bhar, Ramaprasad
2005-01-01
This book offers the opportunity to study and experience advanced empi- cal techniques in finance and in general financial economics. It is not only suitable for students with an interest in the field, it is also highly rec- mended for academic researchers as well as the researchers in the industry. The book focuses on the contemporary empirical techniques used in the analysis of financial markets and how these are implemented using actual market data. With an emphasis on Implementation, this book helps foc- ing on strategies for rigorously combing finance theory and modeling technology to extend extant considerations in the literature. The main aim of this book is to equip the readers with an array of tools and techniques that will allow them to explore financial market problems with a fresh perspective. In this sense it is not another volume in eco- metrics. Of course, the traditional econometric methods are still valid and important; the contents of this book will bring in other related modeling topics tha...
Kernel based orthogonalization for change detection in hyperspectral images
DEFF Research Database (Denmark)
Nielsen, Allan Aasbjerg
function and all quantities needed in the analysis are expressed in terms of this kernel function. This means that we need not know the nonlinear mappings explicitly. Kernel PCA and MNF analyses handle nonlinearities by implicitly transforming data into high (even infinite) dimensional feature space via...... analysis all 126 spectral bands of the HyMap are included. Changes on the ground are most likely due to harvest having taken place between the two acquisitions and solar effects (both solar elevation and azimuth have changed). Both types of kernel analysis emphasize change and unlike kernel PCA, kernel MNF...
Circular parameters of polynomials orthogonal on several arcs of the unit circle
International Nuclear Information System (INIS)
Lukashov, A L
2004-01-01
The asymptotic behaviour of the circular parameters (a n ) of the polynomials orthogonal on the unit circle with respect to Geronimus measures is analysed. It is shown that only when the harmonic measures of the arcs making up the support of the orthogonality measure are rational do the corresponding parameters form a pseudoperiodic sequence starting from some index (that is, after a suitable rotation of the circle and the corresponding modification of the orthogonality measures they form a periodic sequence). In addition it is demonstrated that if the harmonic measures of these arcs are linearly independent over the field of rational numbers, then the sets of limit points of the sequences of absolute values of the circular parameters |a n | and of their ratios (a n+k /a n ) n=1 ∞ are a closed interval on the real line and a continuum in the complex plane, respectively.
Kozma, Eszter; Demeter, Orsolya; Kele, Péter
2017-03-16
Bio-orthogonal labelling schemes based on inverse-electron-demand Diels-Alder (IEDDA) cycloaddition have attracted much attention in chemical biology recently. The appealing features of this reaction, such as the fast reaction kinetics, fully bio-orthogonal nature and high selectivity, have helped chemical biologists gain deeper understanding of biochemical processes at the molecular level. Listing the components and discussing the possibilities and limitations of these reagents, we provide a recent snapshot of the field of IEDDA-based biomolecular manipulation with special focus on fluorescent modulation approaches through the use of bio-orthogonalized building blocks. At the end, we discuss challenges that need to be addressed for further developments in order to overcome recent limitations and to enable researchers to answer biomolecular questions in more detail. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.
Bi-orthogonality conditions for power flow analysis in fluid-loaded elastic cylindrical shells
DEFF Research Database (Denmark)
Ledet, Lasse; Sorokin, Sergey V.; Larsen, Jan Balle
2015-01-01
The paper addresses the classical problem of time-harmonic forced vibrations of a fluid-loaded cylindrical shell considered as a multi-modal waveguide carrying infinitely many waves. Firstly, a modal method for formulation of Green’s matrix is derived by means of modal decomposition. The method...... builds on the recent advances on bi-orthogonality conditions for multi-modal waveguides, which are derived here for an elastic fluid-filled cylindrical shell. Subsequently, modal decomposition is applied to the bi-orthogonality conditions to formulate explicit algebraic equations to express the modal...... vibro-acoustic waveguide is subjected to separate pressure and velocity acoustical excitations. Further, it has been found and justified that the bi-orthogonality conditions can be used as a ’root finder’ to solve the dispersion equation. Finally, it is discussed how to predict the response of a fluid...
Designing Uniquely Addressable Bio-orthogonal Synthetic Scaffolds for DNA and RNA Origami.
Kozyra, Jerzy; Ceccarelli, Alessandro; Torelli, Emanuela; Lopiccolo, Annunziata; Gu, Jing-Ying; Fellermann, Harold; Stimming, Ulrich; Krasnogor, Natalio
2017-07-21
Nanotechnology and synthetic biology are rapidly converging, with DNA origami being one of the leading bridging technologies. DNA origami was shown to work well in a wide array of biotic environments. However, the large majority of extant DNA origami scaffolds utilize bacteriophages or plasmid sequences thus severely limiting its future applicability as a bio-orthogonal nanotechnology platform. In this paper we present the design of biologically inert (i.e., "bio-orthogonal") origami scaffolds. The synthetic scaffolds have the additional advantage of being uniquely addressable (unlike biologically derived ones) and hence are better optimized for high-yield folding. We demonstrate our fully synthetic scaffold design with both DNA and RNA origamis and describe a protocol to produce these bio-orthogonal and uniquely addressable origami scaffolds.
Dual comb generation from a mode-locked fiber laser with orthogonally polarized interlaced pulses.
Akosman, Ahmet E; Sander, Michelle Y
2017-08-07
Ultra-high precision dual-comb spectroscopy traditionally requires two mode-locked, fully stabilized lasers with complex feedback electronics. We present a novel mode-locked operation regime in a thulium-holmium co-doped fiber laser, a frequency-halved state with orthogonally polarized interlaced pulses, for dual comb generation from a single source. In a linear fiber laser cavity, an ultrafast pulse train composed of co-generated, equal intensity and orthogonally polarized consecutive pulses at half of the fundamental repetition rate is demonstrated based on vector solitons. Upon optical interference of the orthogonally polarized pulse trains, two stable microwave RF beat combs are formed, effectively down-converting the optical properties into the microwave regime. These co-generated, dual polarization interlaced pulse trains, from one all-fiber laser configuration with common mode suppression, thus provide an attractive compact source for dual-comb spectroscopy, optical metrology and polarization entanglement measurements.
A square-plate ultrasonic linear motor operating in two orthogonal first bending modes.
Chen, Zhijiang; Li, Xiaotian; Chen, Jianguo; Dong, Shuxiang
2013-01-01
A novel square-plate piezoelectric ultrasonic linear motor operated in two orthogonal first bending vibration modes (B₁) is proposed. The piezoelectric vibrator of the linear motor is simply made of a single PZT ceramic plate (sizes: 15 x 15 x 2 mm) and poled in its thickness direction. The top surface electrode of the square ceramic plate was divided into four active areas along its two diagonal lines for exciting two orthogonal B₁ modes. The achieved driving force and speed from the linear motor are 1.8 N and 230 mm/s, respectively, under one pair orthogonal voltage drive of 150 V(p-p) at the resonance frequency of 92 kHz. The proposed linear motor has advantages over conventional ultrasonic linear motors, such as relatively larger driving force, very simple working mode and structure, and low fabrication cost.
The advantages of orthogonal acceleration in ICP time-of-flight mass spectrometry
International Nuclear Information System (INIS)
Gaal, Andrew
2004-01-01
The OptiMass 8000 incorporates an orthogonal acceleration time-of-flight mass spectrometer. A general schematic of the instrument is given. The continuous ion beam is chopped by an orthogonal accelerator. A push out pulse supply is coupled to the accelerator for providing repetitive push-out voltages at a frequency of 30 kHz. The ion packets that are sliced out of the beam then travel within the field free space towards the SMARTGATE ion blanker. Orthogonal accelerator parameters are set to enable temporal-spatial focusing at the SMARTGATE ion blanker, so that iso-mass ion packets are resolved in time. Any ion packets of unwanted specie are ejected from the direction of travel by supplying pulsed voltages onto the deflection plates of the SMARTGATE. The ions to be measured are let through SMARTGATE and travel further down the field free space, to enter the ion reflectron. The ion reflectron increases the resolution of the mass spectrometer by means of temporal-energy focussing. After reflection, the ions travel within the field free space towards the discrete-dynode detector. In comparison to other acceleration geometries used in elemental time-of-flight mass spectrometry the OptiMass 8000 orthogonal acceleration geometry ultimately leads to superior resolution. As the energy spread is about 3 orders of magnitude lower in the time-of-flight direction for an oaTOFMS in comparison to an on-axis system, aberration acquired in the initial stages of acceleration are much lower. As a result the orthogonal acceleration scheme provides superior resolution at the first spatial focus point and the detector. The orthogonal acceleration time-of-flight analyzer of the OptiMass 8000 is able to provide resolution of at least 1800 at mass 238. (author)
Energy Technology Data Exchange (ETDEWEB)
Starke, G. [Universitaet Karlsruhe (Germany)
1994-12-31
For nonselfadjoint elliptic boundary value problems which are preconditioned by a substructuring method, i.e., nonoverlapping domain decomposition, the author introduces and studies the concept of subspace orthogonalization. In subspace orthogonalization variants of Krylov methods the computation of inner products and vector updates, and the storage of basis elements is restricted to a (presumably small) subspace, in this case the edge and vertex unknowns with respect to the partitioning into subdomains. The author investigates subspace orthogonalization for two specific iterative algorithms, GMRES and the full orthogonalization method (FOM). This is intended to eliminate certain drawbacks of the Arnoldi-based Krylov subspace methods mentioned above. Above all, the length of the Arnoldi recurrences grows linearly with the iteration index which is therefore restricted to the number of basis elements that can be held in memory. Restarts become necessary and this often results in much slower convergence. The subspace orthogonalization methods, in contrast, require the storage of only the edge and vertex unknowns of each basis element which means that one can iterate much longer before restarts become necessary. Moreover, the computation of inner products is also restricted to the edge and vertex points which avoids the disturbance of the computational flow associated with the solution of subdomain problems. The author views subspace orthogonalization as an alternative to restarting or truncating Krylov subspace methods for nonsymmetric linear systems of equations. Instead of shortening the recurrences, one restricts them to a subset of the unknowns which has to be carefully chosen in order to be able to extend this partial solution to the entire space. The author discusses the convergence properties of these iteration schemes and its advantages compared to restarted or truncated versions of Krylov methods applied to the full preconditioned system.
Compassion: An Evolutionary Analysis and Empirical Review
Goetz, Jennifer L.; Keltner, Dacher; Simon-Thomas, Emiliana
2010-01-01
What is compassion? And how did it evolve? In this review, we integrate three evolutionary arguments that converge on the hypothesis that compassion evolved as a distinct affective experience whose primary function is to facilitate cooperation and protection of the weak and those who suffer. Our empirical review reveals compassion to have distinct appraisal processes attuned to undeserved suffering, distinct signaling behavior related to caregiving patterns of touch, posture, and vocalization...
Kähler, Sven; Olsen, Jeppe
2017-11-01
A computational method is presented for systems that require high-level treatments of static and dynamic electron correlation but cannot be treated using conventional complete active space self-consistent field-based methods due to the required size of the active space. Our method introduces an efficient algorithm for perturbative dynamic correlation corrections for compact non-orthogonal MCSCF calculations. In the algorithm, biorthonormal expansions of orbitals and CI-wave functions are used to reduce the scaling of the performance determining step from quadratic to linear in the number of configurations. We describe a hierarchy of configuration spaces that can be chosen for the active space. Potential curves for the nitrogen molecule and the chromium dimer are compared for different configuration spaces. Already the most compact spaces yield qualitatively correct potentials that with increasing size of configuration spaces systematically approach complete active space results.
Atomic and electronic structure of the CdTe(111)B–(2√3 × 4) orthogonal surface
Energy Technology Data Exchange (ETDEWEB)
Bekenev, V. L., E-mail: bekenev@ipms.kiev.ua; Zubkova, S. M. [National Academy of Sciences of Ukraine, Frantsevych Institute for Problems of Materials Science (Ukraine)
2017-01-15
The atomic and electronic structure of four variants of Te-terminated CdTe(111)B–(2√3 × 4) orthogonal polar surface (ideal, relaxed, reconstructed, and reconstructed with subsequent relaxation) are calculated ab initio for the first time. The surface is modeled by a film composed of 12 atomic layers with a vacuum gap of ~16 Å in the layered superlattice approximation. To close Cd dangling bonds on the opposite side of the film, 24 fictitious hydrogen atoms with a charge of 1.5 electrons each are added. Ab initio calculations are performed using the Quantum Espresso program based on density functional theory. It is demonstrated that relaxation leads to splitting of the four upper layers. The band energy structures and total and layer-by-layer densities of electronic states for the four surface variants are calculated and analyzed.
International Nuclear Information System (INIS)
Cao Tianjie; Zhou Zegong
1993-01-01
This paper presents some methods to assess the fracture failure probability of a spherical tank. These methods convert the assessment of the fracture failure probability into the calculation of the moment of cracks and a one-dimensional integral. In the paper, we first derive series' formulae to calculation the moments of cracks on the occasion of the crack fatigue growth and the moments of crack opening displacements according to JWES-2805 code. We then use the first n moments of crack opening displacements and a few orthogonal polynomials to compose the probability density function of the crack opening displacement. Lastly, the fracture failure probability is obtained according to the interference theory. An example proves that these methods are simpler, quicker, and more accurate. At the same time, these methods avoid the disadvantage of Edgeworth's series method. (author)
Energy Technology Data Exchange (ETDEWEB)
Park, Ju Yeop; In, Wang Kee; Chun, Tae Hyun; Oh, Dong Seok [Korea Atomic Energy Research Institute, Taejeon (Korea)
2000-02-01
The development of orthogonal 2-dimensional numerical code is made. The present code contains 9 kinds of turbulence models that are widely used. They include a standard k-{epsilon} model and 8 kinds of low Reynolds number ones. They also include 6 kinds of numerical schemes including 5 kinds of low order schemes and 1 kind of high order scheme such as QUICK. To verify the present numerical code, pipe flow, channel flow and expansion pipe flow are solved by this code with various options of turbulence models and numerical schemes and the calculated outputs are compared to experimental data. Furthermore, the discretization error that originates from the use of standard k-{epsilon} turbulence model with wall function is much more diminished by introducing a new grid system than a conventional one in the present code. 23 refs., 58 figs., 6 tabs. (Author)
Final Empirical Test Case Specification
DEFF Research Database (Denmark)
Kalyanova, Olena; Heiselberg, Per
This document includes the empirical specification on the IEA task of evaluation building energy simulation computer programs for the Double Skin Facades (DSF) constructions. There are two approaches involved into this procedure, one is the comparative approach and another is the empirical one....
Directory of Open Access Journals (Sweden)
Robert Aldrich
2010-03-01
Full Text Available This paper argues that the colonial legacy is ever present in contemporary Europe. For a generation, most Europeans largely tried, publicly, to forget the colonial past, or remembered it only through the rose-coloured lenses of nostalgia; now the pendulum has swung to memory of that past – even perhaps, in the views of some, to a surfeit of memory, where each group agitates for its own version of history, its own recognition in laws and ceremonies, its own commemoration in museums and monuments, the valorization or repatriation of its own art and artefacts. Word such as ‘invasion,’ ‘racism’ and ‘genocide’ are emotional terms that provoke emotional reactions. Whether leaders should apologize for wrongs of the past – and which wrongs – remains a highly sensitive issue. The ‘return of the colonial’ thus has to do with ethics and politics as well as with history, and can link to statements of apology or recognition, legislation about certain views of history, monetary compensation, repatriation of objects, and—perhaps most importantly—redefinition of national identity and policy. The colonial flags may have been lowered, but many barricades seem to have been raised. Private memories—of loss of land, of unacknowledged service, of political, economic, social and cultural disenfranchisement, but also on the other side of defeat, national castigation and self-flagellation—have been increasingly public. Monuments and museums act not only as sites of history but as venues for political agitation and forums for academic debate – differences of opinion that have spread to the streets. Empire has a long after-life.
Islam, Muhammad F.; Islam, Mohammed N.
2012-04-01
The objective of this paper is to develop a novel approach for encryption and compression of biometric information utilizing orthogonal coding and steganography techniques. Multiple biometric signatures are encrypted individually using orthogonal codes and then multiplexed together to form a single image, which is then embedded in a cover image using the proposed steganography technique. The proposed technique employs three least significant bits for this purpose and a secret key is developed to choose one from among these bits to be replaced by the corresponding bit of the biometric image. The proposed technique offers secure transmission of multiple biometric signatures in an identification document which will be protected from unauthorized steganalysis attempt.
Directory of Open Access Journals (Sweden)
Iman Yousefi
2015-01-01
Full Text Available This paper presents parameter estimation of Permanent Magnet Synchronous Motor (PMSM using a combinatorial algorithm. Nonlinear fourth-order space state model of PMSM is selected. This model is rewritten to the linear regression form without linearization. Noise is imposed to the system in order to provide a real condition, and then combinatorial Orthogonal Projection Algorithm and Recursive Least Squares (OPA&RLS method is applied in the linear regression form to the system. Results of this method are compared to the Orthogonal Projection Algorithm (OPA and Recursive Least Squares (RLS methods to validate the feasibility of the proposed method. Simulation results validate the efficacy of the proposed algorithm.