A post processing technique for improved harmonic/percussion separation in polyphonic speech

In this paper we propose a postprocessing technique for a spectrogram diffusion based harmonic/percussion decom- position algorithm. The proposed technique removes har- monic instrument leakages in the percussion enhanced out- puts of the baseline algorithm. The technique uses median filtering and an adaptive detection of percussive segments in subbands followed by piecewise signal reconstruction using envelope properties to ensure that percussion is enhanced while harmonic leakages are suppressed. A new binary mask is created for the percussion signal which upon applying on the original signal improves harmonic versus percussion separation. We compare our algorithm with two recent techniques and show that on a database of polyphonic Indian music, the postprocessing algorithm improves the harmonic versus percussion decomposition significantly.

Reconstruction from incomplete data in cone-beam tomography

A method for reconstruction of an object f(x) x=(x,y,z) from a limited set of cone-beam projection data has been developed. This method uses a modified form of convolution back-projection and projection onto convex sets (POCS) for handling the limited (or incomplete) data problem. In cone-beam tomography, one needs to have a complete geometry to completely reconstruct the original three-dimensional object. While complete geometries do exist, they are of little use in practical implementations. The most common trajectory used in practical scanners is circular, which is incomplete. It is, however, possible to recover some of the information of the original signal f(x) based on a priori knowledge of the nature of f(x). If this knowledge can be posed in a convex set framework, then POCS can be utilized. In this report, we utilize this a priori knowledge as convex set constraints to reconstruct f(x) using POCS. While we demonstrate the effectiveness of our algorithm for circular trajectories, it is essentially geometry independent and will be useful in any limited-view cone-beam reconstruction.

Cyclone-induced mixing does not cool SST in the post-monsoon north Bay of Bengal

High-resolution data from the TRMM satellite shows that sea surface temperature (SST) cools by 3 degrees C under the tracks of pre-monsoon tropical cyclones in the north Indian Ocean. However, even the strongest post-monsoon cyclones do not cool the open north Bay of Bengal. In this region, a shallow layer of freshwater from river runoff and monsoon rain caps a deep warm layer. Therefore, storm-induced mixing is not deep, and it entrains warm subsurface water. It is possible that the hydrography of the post-monsoon north Bay favours intense cyclones.

Consanguinity, fecundity and post-natal mortality in Karnataka, South India

The degree of consanguinity of the progeny, the number of live-borns and number of living children were determined in 3350 marriages in Bangalore, Karnataka. The coefficient of inbreeding (F) was 0•02308, higher than in comparable, urban populations in other South Indian states. No significant differences were found between the consanguineous and non-consanguineous groups in numbers of live-born or living children nor was there any consanguinity-related trend with respect to these parameters.

Image reconstruction with laterally truncated projections in helical cone-beam CT: Linear prediction based projection completion techniques

Lateral or transaxial truncation of cone-beam data can occur either due to the field of view limitation of the scanning apparatus or iregion-of-interest tomography. In this paper, we Suggest two new methods to handle lateral truncation in helical scan CT. It is seen that reconstruction with laterally truncated projection data, assuming it to be complete, gives severe artifacts which even penetrates into the field of view. A row-by-row data completion approach using linear prediction is introduced for helical scan truncated data. An extension of this technique known as windowed linear prediction approach is introduced. Efficacy of the two techniques are shown using simulation with standard phantoms. A quantitative image quality measure of the resulting reconstructed images are used to evaluate the performance of the proposed methods against an extension of a standard existing technique.

Estimation of cosmological parameters from neutral hydrogen observations of the post-reionization epoch

The emission from neutral hydrogen (HI) clouds in the post-reionization era (z <= 6), too faint to be individually detected, is present as a diffuse background in all low frequency radio observations below 1420MHz. The angular and frequency fluctuations of this radiation (similar to 1 mK) are an important future probe of the large-scale structures in the Universe. We show that such observations are a very effective probe of the background cosmological model and the perturbed Universe. In our study we focus on the possibility of determining the redshift-space distortion parameter beta, coordinate distance r(nu), and its derivative with redshift r(nu)('). Using reasonable estimates for the observational uncertainties and configurations representative of the ongoing and upcoming radio interferometers, we predict parameter estimation at a precision comparable with supernova Ia observations and galaxy redshift surveys, across a wide range in redshift that is only partially accessed by other probes. Future HI observations of the post-reionization era present a new technique, complementing several existing ones, to probe the expansion history and to elucidate the nature of the dark energy.

On a Two-Dimensional Problem in the End-Block Design of Post-Tensioned Prestressed Concrete Beams

Abstract is not available.

Stress Concentration in Post-Tensioned Prestressed Concrete Beams

The use of the multiple Fourier method to analyses the stress distribution in the and regions of as a post-tensioned prestressed concrete beam had shown. The multiple Fourier method demonstrated have is a relatively new method for solving those problems for which the “Saint Vansant principle” is not applicable, The actual three-dimensional problem and a two-dimensional simplified representation of it are treated. The two-dimensional case is treated first and rather completely to gain further experience with multiple Fourier procedure, the appropriate Galerkin Vector for the three-dimensional case is found and the required relations between the arbitrary functions are stated.

Tree-ring based hydroclimate reconstruction over northern Vietnam from Fokienia hodginsii: eighteenth century mega-drought and tropical Pacific influence

We present here the first statistically calibrated and verified tree-ring reconstruction of climate from continental Southeast Asia.The reconstructed variable is March-May (MAM) Palmer Drought Severity Index (PDSI) based on ring widths from 22 trees (42 radial cores) of rare and long-lived conifer, Fokienia hodginsii (Po Mu as locally called) from northern Vietnam. This is the first published tree ring chronology from Vietnam as well as the first for this species. Spanning 535 years, this is the longest cross-dated tree-ring series yet produced from continental Southeast Asia. Response analysis revealed that the annual growth of Fokienia at this site was mostly governed by soil moisture in the pre-monsoon season. The reconstruction passed the calibration-verification tests commonly used in dendroclimatology, and revealed two prominent periods of drought in the mid-eighteenth and late-nineteenth enturies. The former lasted nearly 30 years and was concurrent with a similar drought over northwestern Thailand inferred from teak rings, suggesting a ``mega-drought'' extending across Indochina in the eighteenth century. Both of our reconstructed droughts are consistent with the periods of warm sea surface temperature (SST)anomalies in the tropical Pacific. Spatial correlation analyses with global SST indicated that ENSO-like anomalies might play a role in modulating droughts over the region, with El Nio (warm) phases resulting in reduced rainfall. However, significant correlation was also seen with SST over the Indian Ocean and the north Pacific,suggesting that ENSO is not the only factor affecting the climate of the area. Spectral analyses revealed significant peaks in the range of 53.9-78.8 years as well as in the ENSO-variability range of 2.0 to 3.2 years.

K-Ar ages of biotite and muscovite from Pangong metamorphic complex, Shyok suture zone, India: Implications for the youngest post-collision metamorphic event in Ladakh Himalaya

The garnet-kyanite-staurolite and garnet-biotite-staurolite gneisses were collected from a locality within Lukung area that belongs to the Pangong metamorphic complex in Shyok valley, Ladakh Himalaya. The kyanite-free samples have garnet and staurolite in equilibrium, where garnets show euhedral texture and have flat compositional profile. On the other hand, the kyanite-bearing sample shows equilibrium assemblage of garnet-kyanite-staurolite along with muscovite and biotite. In this case, garnet has an inclusion rich core with a distinct grain boundary, which was later overgrown by inclusion free euhedral garnet. Garnet cores are rich in Mn and Ca, while the rims are poor in Mn and rich in Fe and Mg, suggesting two distinct generations of growth. However, the compositional profiles and textural signature of garnets suggests the same stage of P -T evolution for the formation of the inclusion free euhedral garnets in the kyanite-free gneisses and the inclusion free euhedral garnet rims in the kyanite-bearing gneiss. Muscovites from the four samples have consistent K-Ar ages, suggesting the cooling age (∼ 10 Ma) of the gneisses. These ages make a constraint on the timing of the youngest post-collision metamorphic event that may be closely related to an activation of the Karakoram fault in Pangong metamorphic complex.

Iterative solution of a class of linear equations with application to reconstruction of three-dimensional object arrays

An iterative algorithm baaed on probabilistic estimation is described for obtaining the minimum-norm solution of a very large, consistent, linear system of equations AX = g where A is an (m times n) matrix with non-negative elements, x and g are respectively (n times 1) and (m times 1) vectors with positive components.

Post-liquefaction undrained monotonic behaviour of sands: experiments and DEM simulations

This paper presents the results of a series of servo-controlled cyclic triaxial tests and numerical simulations using the three- dimensional discrete element method (DEM) on post-liquefaction undrained monotonic strength of granular materials. In a first test series,undrained monotonic tests were carried out after dissipating the excess pore water pressure developed during liquefaction. The influence of different parameters such as amplitude of axial strain,relative density and confining pressure prior to liquefaction on the post-liquefaction undrained response have been investigated.The results obtained highlight an insignificant influence of amplitude of axial strain, confining pressure and a significant influence of relative density on the post-liquefaction undrained monotonic stress-strain response.In the second series, undrained monotonic tests were carried out on similar triaxial samples without dissipating the excess pore water pressure developed during liquefaction. The results highlight that the amplitude of axial strain prior to liquefaction has a significant influence on the post-liquefaction undrained monotonic response.In addition,DEM simulations have been carried out on an assembly of spheres to simulate post-liquefaction behaviour.The simulations were very similar to the experiments with an objective to understand the behaviour of monotonic strength of liquefied samples from the grain scale. The numerical simulations using DEM have captured qualitatively all the features of the post-liquefaction undrained monotonic response in a manner similar to that of the experiments.In addition,a detailed study on the evolution of micromechanical parameters such as the average coordination number and induced anisotropic coefficients has been reported during the post-liquefaction undrained monotonic loading.

Third post-Newtonian angular momentum flux and the secular evolution of orbital elements for inspiralling compact binaries in quasi-elliptical orbits

The angular-momentum flux from an inspiralling binary system of compact objects moving in quasi-elliptical orbits is computed at the third post-Newtonian (3PN) order using the multipolar post-Minkowskian wave generation formalism. The 3PN angular-momentum flux involves the instantaneous, tail, and tail-of-tails contributions as for the 3PN energy flux, and in addition a contribution due to nonlinear memory. We average the angular-momentum flux over the binary's orbit using the 3PN quasi-Keplerian representation of elliptical orbits. The averaged angular-momentum flux provides the final input needed for gravitational-wave phasing of binaries moving in quasi-elliptical orbits. We obtain the evolution of orbital elements under 3PN gravitational radiation reaction in the quasi-elliptic case. For small eccentricities, we give simpler limiting expressions relevant for phasing up to order e(2). This work is important for the construction of templates for quasi-eccentric binaries, and for the comparison of post-Newtonian results with the numerical relativity simulations of the plunge and merger of eccentric binaries.

Performance Analysis of Reconstruction Techniques for Frequency-Domain Optical-Coherence Tomography

We address the issue of noise robustness of reconstruction techniques for frequency-domain optical-coherence tomography (FDOCT). We consider three reconstruction techniques: Fourier, iterative phase recovery, and cepstral techniques. We characterize the reconstructions in terms of their statistical bias and variance and obtain approximate analytical expressions under the assumption of small noise. We also perform Monte Carlo analyses and show that the experimental results are in agreement with the theoretical predictions. It turns out that the iterative and cepstral techniques yield reconstructions with a smaller bias than the Fourier method. The three techniques, however, have identical variance profiles, and their consistency increases linearly as a function of the signal-to-noise ratio.

Seismic Microzonation: A Tool for Disaster Mitigation Planning

Seismic microzonation has generally been recognized as the most accepted tool in seismic hazard assessment and risk evaluation. In general, risk reduction can be done by reducing the hazard, the vulnerability or the value at risk. Since the earthquake hazard can not be reduced, one has to concentrate on vulnerability and value at risk. The vulnerability of an urban area / municipalities depends on the vulnerability of infrastructure and redundancies within the infrastructure. The earthquake risk is the damage to buildings along with number of people that are killed / hurt and the economic losses during the event due to an earthquake with a return period corresponding to this time period. The principal approaches one can follow to reduce these losses are to avoid, if possible, high hazard areas for the siting of buildings and infrastructure, and further ensure that the buildings and infrastructure are designed and constructed to resist expected earthquake loads. This can be done if one can assess the hazard at local scales. Seismic microzonation maps provide the basis for scientifically based decision-making to reduce earthquake risk for Govt./public agencies, private owners and the general public. Further, seismic microzonation carried out on an appropriate scale provides a valuable tool for disaster mitigation planning and emergency response planning for urban centers / municipalities. It provides the basis for the identification of the areas of the city / municipality which are most likely to experience serious damage in the event of an earthquake.