Fast Fluid Simulations with Sparse Volumes on the GPU

We introduce efficient, large scale fluid simulation on GPU hardware using the fluid‐implicit particle (FLIP) method over a sparse hierarchy of grids represented in NVIDIA^® GVDB Voxels. Our approach handles tens of millions of particles within a virtually unbounded simulation domain. We describe novel techniques for parallel sparse grid hierarchy construction and fast incremental updates on the GPU for moving particles. In addition, our FLIP technique introduces sparse, work efficient parallel data gathering from particle to voxel, and a matrix‐free GPU‐based conjugate gradient solver optimized for sparse grids. Our results show that our method can achieve up to an order of magnitude faster simulations on the GPU as compared to FLIP simulations running on the CPU.     

Dynamics of serial chain systems using dual algebra

Multibody System Dynamics - Dynamic modelling of a multibody system is critical to analyse its behaviour under different circumstances. This paper proposes the dynamic modelling of a rigid...     

The effect of heat setting on the dyeability of differentially dyeable polyester fibres

Apparent diffusion coefficients of two disperse dyes for so-called easily dyeable/cationic-dyeable polyester (ED-CDPET) and cationic-dyeable polyester (CDPET) fibres of identical linear density and sulphonic acid group content have been calculated. It was found that the diffusion coefficients of dyes for ED-CDPET were far greater than those of dyes for CDPET. The dyeability at the boil without carrier, using disperse and cationic dyes on various ED-CDPET and CDPET fibres, has been studied. ED-CDPET was found to have higher dyeability at all levels of heat setting (irrespective of the dye used). The finest ED-CDPET fibres showed maximum dye uptake as a result of increased surface area. Heat setting in the taut condition reduced dye uptake.     

Lumped heat and mass transfer coefficient for simulation of a pressure swing adsorption process

The practical implications of replacing various individual transport resistances such as gas-solid mass and heat transfer, and gas phase axial dispersions of mass and heat in a numerical model of a pressure swing adsorption (PSA) process by a single, empirical, lumped, effective mass transport coefficient were evaluated. A non-isothermal, adiabatic, four-step Skarstrom-like PSA process for production of pure helium from a binary helium-nitrogen mixture using 5A zeolite adsorbent was considered. It was found that the above-described model simplification was adequate to describe key process performances such as the bed size factor and the product recovery vis-a-vis a detailed model where the effects of all individual resistances were explicitly included.     

Analysis of Full-Duplex Downlink Using Diversity Gain

Wireless Personal Communications - In this paper, we carry out performance analysis of a multiuser full-duplex (FD) communication system. Multiple FD user equipments (UEs) share the same spectrum...     

Robust optimum design of tuned liquid column damper in seismic vibration control of structures under uncertain bounded system parameters

The optimum design of a tuned liquid column damper (TLCD) considering system parameter uncertainty is usually performed by minimising the performance measure obtained by the total probability theory without any consideration to the variation of its performance due to parameter uncertainty. However, such a design method does not necessarily correspond to an optimum design in terms of maximum response reduction as well as its minimum dispersion. Furthermore, such approach cannot be applied in many real situations when the required detailed information about the uncertain parameters is limited. The robust design optimisation (RDO) of a TLCD system to mitigate seismic vibration effect in which the bounds on the magnitude of the uncertain properties of the structural and ground motion model parameters are only required is attempted in this study. The RDO is formulated as a two-criterion optimisation problem where the weighted sum of the maximum root mean square displacement of the structure and its dispersion is minimised. The conventional interval analysis-based bounded optimum solution is also obtained to demonstrate the effectiveness of the proposed RDO approach. A numerical study elucidates the effect of parameter uncertainty on the RDO of TLCD parameters by comparing the RDO results with the bounded optimum results.     

Adsorption and desorption characteristics of lindane, carbofuran and methyl parathion on various Indian soils

Adsorption and desorption characteristics of three insecticides on four Indian soils were studied. Insecticides used were representative of organochlorine, organophosphate, and carbomate groups. The order of adsorption of pesticides on soils was: lindane > methyl parathion > carbofuran. Compost soil had shown the maximum adsorption capacity. The order of adsorption capacity of various soils were: compost soil > clayey soil > red soil > sandy soil. Adsorption isotherms were better fitted to Freundlich model and K_f values increased with increase in organic matter content of the soils. Thermodynamic parameters indicated favorable adsorption of all the three pesticides in four different soils. Adsorption was exothermic in nature. Distilled water desorbed 30–60% of adsorbed pesticides whereas; organic solvents were able to affect 50–80% of sorbed pesticides. Clay content and organic matter played a significant role in pesticide adsorption and desorption processes. Hysteresis effect was observed in red, clayey and compost soils. Hysteresis effect increased with increase in organic matter and clay content of the soils.     

Safety, pharmacokinetics and biodistribution studies of a beta-galactoside prodrug of doxorubicin for improvement of tumor selective chemotherapy

Anthracycline antibiotics, particularly doxorubicin (DOX) and daunorubicin, have been used extensively in the treatment of human malignancies. However, cardiotoxicity and multidrug resistance are significant problems that limit the clinical efficacy of such agents. Rational design to avoid these side effects includes strategies such as drug targeting and prodrug synthesis. The DOX prodrug N-(beta-D-glucopyranosylbenzyloxycarbonyl)-doxorubicin (prodrug 1) was synthesized for specific activation by beta-galactosidase, which is expected to release in necrotic areas of tumor lesions. Described here is the safety, pharmacokinetics, and biodistribution studies of a beta-galactoside prodrug of DOX. In vivo safety evaluation was done in the Ehrlich Ascites Carcinoma (EAC) tumor model. The dose of DOX was 8 mg/kg and the dose of prodrug was 8 mg/kg and 24 mg/kg of DOX equivalents. Our results on cytotoxicity, which demonstrated compression in the number of EAC cells and their viability, substantiate these data. Prodrug 1 was safe up to a dose of 24 mg/kg of DOX equivalents in EAC mice. The pharmacokinetics and biodistribution of prodrug (300 mg/kg) in normal mice were determined and compared with DOX (20 mg/kg). Administration of DOX in normal mice resulted in a peak plasma concentration of 19.45 microM (t = 30 minutes). Prodrug injection resulted in 3- to 16-fold lower concentrations in the tissues of normal mice. As it is more polar, lower levels were observed in tissues and plasma in contrast to the parent compound DOX. In vivo safety studies have shown that prodrug 1 had a maximum tolerated dose compared with DOX and led to improved pharmacokinetics in normal mice.     

Epoch Extraction by Phase Modelling of Speech Signals

Epochs are instants of significant excitation of vocal-tract system in speech production process. In this paper, we attempt to extract information about epochs from phase spectra of speech signals. The phase spectrum of speech is modelled as the response of an allpass (AP) filter, and the resulting error signal is used for epoch extraction. The parameters of AP model are estimated by imposing sparsity constraints on the error signal. The error signal, thus obtained, exhibits prominent peaks at epoch locations. The epochal candidates obtained from the error signal are refined using a dynamic programming algorithm. The performance of the proposed method is consistent across genders and is comparable with the state-of-the-art methods.