Time-domain analysis of cross correlation for time delay estimationwith an autocorrelated signal

The estimation accuracy of the time difference of arrival (TDOA) of an exponentially autocorrelated signal at two sensors in white noise is analyzed. The estimate is obtained by cross correlating samples taken as short-term integrals of the noisy signals from the two sensors. This technique avoids ambiguities in the cross correlation, and it is shown that the best sampling rate is double the Nyquist rate, for which the Cramer-Rao lower bound (CRLB) is met in practice     

Design and development of a machine vision system using artificial neural network-based algorithm for automated coal characterization

Coal is heterogeneous in nature,and thus the characterization of coal is essential before its use for a specific purpose.Thus,the current study aims to develop ...     

Development of Nd (III)-Based Terahertz Absorbers Revealing Temperature Dependent Near-Infrared Luminescence

Molecular vibrations in the solid-state, detectable in the terahertz (THz) region, are the subject of research to further develop THz technologies. To observe such vibrations in terahertz time-domain spectroscopy (THz-TDS) and low-frequency (LF) Raman spectroscopy, two supramolecular assemblies with the formula [Nd^III (phen)₃ (NCX)₃] 0.3EtOH (X = S, 1-S; Se, 1-Se) were designed and prepared. Both compounds show several THz-TDS and LF-Raman peaks in the sub-THz range, with the lowest frequencies of 0.65 and 0.59 THz for 1-S and 1-Se, and 0.75 and 0.61 THz for 1-S and 1-Se, respectively. The peak redshift was observed due to the substitution of SCN⁻ by SeCN⁻. Additionally, temperature-dependent TDS-THz studies showed a thermal blueshift phenomenon, as the peak position shifted to 0.68 THz for 1-S and 0.62 THz for 1-Se at 10 K. Based on ab initio calculations, sub-THz vibrations were ascribed to the swaying of the three thiocyanate/selenocyanate. Moreover, both samples exhibited near-infrared (NIR) emission from Nd (III), and very good thermometric properties in the 300–150 K range, comparable to neodymium (III) oxide-based thermometers and higher than previously reported complexes. Moreover, the temperature dependence of fluorescence and THz spectroscopy analysis showed that the reduction in anharmonic thermal vibrations leads to a significant increase in the intensity and a reduction in the width of the emission and LF absorption peaks. These studies provide the basis for developing new routes to adjust the LF vibrational absorption.     

Polarographic Study of Thio-acetic Acid

The polarographic behaviour of thio-acetic acid (RSH) at dropping mercury electrode (d.m.e.) has been investigated in presence of KNO₃ in the pH range 2–10.5 at 30.0 ± 0.2°C in 50% alcoholic medium at 0.2 M ionic strength. Well defined anodic waves were obtained at all pH values in the concentration range studied. At pH < 2.2 and > 10.5 ill defined anodic waves were obtained. The effect of pH, concentration of RSH, temperature, drop time and alcohol on the wave characteristic and the mechanism of the reaction occurring at the surface of the mercury drop have been studied in detail. A small prewave was also observed at pH 9.1 and 10.5, which has been assigned adsorption characteristics. The reversibility of the reaction mechanism was confirmed by a number of methods. The wave is diffusion controlled and reversible involving one electron transfer process: Mathematical and experimental evidence shows that the anodic wave of RSH at. d.m.e. does not correspond to formation of (RSSR) but to a mercury compound RSHg according to the above equation. The diffusion coefficient and temperature coefficient for (30–45°C) of i_d at pH 4.0 and 9.1 have been found to be 1.698; 1.965 × 10⁻⁶ cm²/sec and 1.08%; 1.20% per degree respectively. The dissociation constant pKa was found to be 4.25 by the plot of E_1/2 vs. pH. The linearity of i_d with RSH concentrations provides a rapid and precise method for the determination of RSH down to 0.2 mM.     

Advances in the Therapeutic Effects of Apoptotic Bodies on Systemic Diseases

Apoptosis plays an important role in development and in the maintenance of homeostasis. Apoptotic bodies (ApoBDs) are specifically generated from apoptotic cells and can contain a large variety of biological molecules, which are of great significance in intercellular communications and the regulation of phagocytes. Emerging evidence in recent years has shown that ApoBDs are essential for maintaining homeostasis, including systemic bone density and immune regulation as well as tissue regeneration. Moreover, studies have revealed the therapeutic effects of ApoBDs on systemic diseases, including cancer, atherosclerosis, diabetes, hepatic fibrosis, and wound healing, which can be used to treat potential targets. This review summarizes current research on the generation, application, and reconstruction of ApoBDs regarding their functions in cellular regulation and on systemic diseases, providing strong evidence and therapeutic strategies for further insights into related diseases.     

Wave-induced flow of pore fluid in a cracked porous solid containing penny-shaped inclusions

An aim of current study is to analyze the contribution of reflected longitudinal waves to wave-induced fluid flow(WIFF)in the cracked porous solid.Initially,we ...     

A near-optimum detector with reduced out-of band response fornarrowband signals

Reduced spectral response in adjacent spectral bins is very desirable for detectors since it gives capability to detect narrowband signals in the presence of unknown interference and colored noise. Conventionally, this is achieved by applying a smoothing window on the signal at the cost of detection performance. In this correspondence, a new method of detecting narrowband signals that uses a close approximation to the matched filter and the extrapolated input signal is proposed. The filter used has a frequency response that is very closely equal to that of the matched filter within a Doppler bin and nearly zero response outside it