Semi-blind sparse channel estimation with constant modulus symbols

We propose two methods for the estimation of sparse communication channels. In the first method, we consider the problem of channel estimation based on training symbols, and formulate it as an optimization problem. In this formulation, we combine the objective of fidelity to the received data with a non-quadratic constraint reflecting the prior information about the sparsity of the channel. This approach leads to accurate channel estimates with much shorter training sequences than conventional methods. The second method we propose is aimed at taking advantage of any available training-based data, as well as any "blind" data based on unknown, constant modulus symbols. We propose a semi-blind optimization framework making use of these two types of data, and enforcing the sparsity of the channel, as well as the constant modulus property of the symbols. This approach improves upon the channel estimates based only on training sequences, and also produces accurate estimates for the unknown symbols

The Macroeconomic Determinants of Volatility in Precious Metals Markets

We investigate key macroeconomic factors that impact the price returns of precious metals markets. The markets investigated were gold, silver, platinum and palladium; whereas the macroeconomic factors accommodated business cycle, monetary environment and financial market sentiment factors. The key findings present limited evidence that the same macroeconomic factors jointly influence the volatility processes of the precious metal price series, although there is some evidence of volatility feedback between the precious metals. This finding lends weight to views that individual commodities are too distinct to be considered a single asset class or represented by a single index; a finding of considerable importance for portfolio managers and investors.

With four Standard Model families, the LHC could discover the Higgs boson with a few fb^-1

The existence of a 4th SM family would produce a large enhancement of the gluon fusion channel of Higgs boson production at hadron colliders. In this case, the SM Higgs boson could be seen at the CERN Large Hadron Collider (LHC) via the golden mode (H->4l) with an integral luminosity of only a few fb^-1.Comment: 7 pages, 2 figures, 2 tables, references updated in v

Cancer Cell Cytotoxicities of 1-(4-Substitutedbenzoyl)-4-(4-chlorobenzhydryl) piperazine Derivatives

Cataloged from PDF version of article.A series of novel 1-(4-substitutedbenzoyl)-4-(4-chlorobenzhydryl)piperazine derivatives 5a-g was designed by a nucleophilic substitution reaction of 1-(4-chlorobenzhydryl) piperazine with various benzoyl chlorides and characterized by elemental analyses, IR and H-1 nuclear magnetic resonance spectra. Cytotoxicity of the compounds was demonstrated on cancer cell lines from liver (HUH7, FOCUS, MAHLAVU, HEPG2, HEP3B), breast (MCF7, BT20, T47D, CAMA-1), colon (HCT-116), gastric (KATO-3) and endometrial (MFE-296) cancer cell lines. Time-dependent cytotoxicity analysis of compound 5a indicated the long-term in situ stability of this compound. All compounds showed significant cell growth inhibitory activity on the selected cancer cell lines

A longitudinal study of the relationship between mathematics and science: The case of Texas

Cataloged from PDF version of article.This study aims to investigate the relationship between mathematics and science scores acquired from the Texas Assessment of Knowledge and Skills (TAKS) examination, and how this relationship changed over the years. The participants were from an independent school district in a northern Texas town. Criterion sampling was used in this study to assure that students who were selected had four TAKS mathematics scores from 2006 through 2010 and two TAKS science scores for 2006 and 2010: 116 students met the criteria. The relationship between two subjects was investigated by analyzing the correlation between students’ mathematics and science scores of 2006 and 2010. Growth curve models were used to reveal whether there was growth on students’ mathematics and science scores over the years. A strong correlation was found between mean mathematics and mean science scores in the whole sample, and a greater growth was found in mathematics than it did for science

Warpage characterization of microchannels fabricated by injection molding

Cataloged from PDF version of article.Mass-production of microfluidic devices is important for biomedical applications in which disposable devices are widely used. Injection molding is a well-known process for the production of devices on a mass scale at low-cost. In this study, the injection molding process is adapted for the fabrication of a microfluidic device with a single microchannel. To increase the product quality, high-precision mechanical machining is utilized for the manufacturing of the mold of the microfluidic device. A conventional injection molding machine is implemented in the process. Injection molding was performed at different mold temperatures. The warpage of the injected pieces was characterized by measuring the part deformation. The effect of the mold temperature on the quality of the final device was assessed in terms of the part deformation and bonding quality. From the experimental results, oneto-one correspondence between the warpage and the bonding quality of the molded pieces was observed. It was found that as the warpage of the pieces decreases, the bonding quality increases. A maximum point for the breaking pressure of the bonding and the minimum point for the warpage were found at the same mold temperature. This mold temperature was named as the optimum temperature for the designed microfluidic device. It was observed that the produced microfluidic devices at the mold temperature of 45 !C were able to withstand pressures up to 74 ba