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The design and development of a computer-based system for breast cancer detection are largely reliant on feature selection techniques. These techniques are used to reduce the dimensionality of the feature space by removing irrelevant or redundant features from the original set. This article presents a hybrid feature selection method that is based on the Butterfly optimization algorithm (BOA) and the Ant Lion optimizer (ALO) to form a hybrid BOAALO method. The optimal subset of features chosen by BOAALO is utilized to predict the benign or malignant status of breast tissue using three classifiers: artificial neural network, adaptive neuro-fuzzy inference system, and support vector machine. The goodness of the proposed method is tested using 651 mammogram images. The results show that BOAALO outperforms the original BOA and ALO in terms of accuracy, sensitivity, specificity, kappa value, type-I, and type-II error as well as the receiver operating characteristics curve. Additionally, the suggested method's robustness is assessed and compared to five well-known methods using a benchmark dataset. The experimental findings demonstrate that BOAALO achieves a high degree of accuracy with a minimum number of features. These results support the suggested method's applicability for breast cancer diagnosis.

Recently, study of physical properties of the liquid mixtures, their nature and behavior with change in frequency, temperature or concentration has gained interest. In the present work, ultrasonic velocity and attenuation measurements have been carried out in the binary mixture of nitrobenzene and ethanol using pulse echo technique in the temperature range of 274.15K-308.15K maintaining the temperature of the sample with an accuracy of ±0.1°C. It is observed that the mixture of nitrobenzene and ethanol shows maximum absorption at 277.15K at 0.27 moles of Nitrobenzene in the binary mixture. Critical nature of the mixture revealed by ultrasonic absorption indicates the molecular interaction between two liquids and attributes due to the fluctuation in the concentration.

Urban areas are most dynamic in terms of land use changes. The temporal changes can be monitored through satellite data and reflects the development taking place. Pattern recognition techniques are used to monitor the dynamics. In the present paper, Nagpur city urban sprawl has been studied using band ratioing techniques and fuzzy classification. The result shows an increase in the impervious layer which is the bench mark of urbanization and a corresponding decrease in the vegetation cover and the open spaces. This type of output can be used for planning of industries, garden, rejuvenation of water bodies and monitor the development activities.

In the present work, positional Isomerism is studied in the binary mixtures of n-propyl alcohol and Iso-propyl alcohol in nitrobenzene as the common solvent. Ultrasonic velocity and attenuation measurements using pulse–echo technique operated at 10 MHz have been taken at various concentrations of both alcohols in nitrobenzene, from 283.15K - 293.15K. It is observed that both the systems exhibit critical nature and show non-linear variation both in ultrasonic velocity of propagation and attenuation. Ultrasonic attenuation at lower concentrations of n-propyl alcohol in nitrobenzene reveals the dominant structural relaxation as compared to that of Iso-propyl alcohol in nitrobenzene.

A cluster computer provides much faster processing speed, larger storage capacity, better data integrity, superior reliability and wider availability of resources. In the present work, we have developed a cluster computer using five Raspberry Pi’s (one master and four slave nodes) that acts as a single computer with enhanced processing speed. A Linux based operating system, Raspbian is used in the present work, to manage and access the Raspberry Pi in master node. Message Pass Interface (MPI) protocol is used to share the task among the nodes for parallel processing. The designed cluster computer has been tested using standard programs in C and python. The developed cluster computer is found to work successfully. The facilities of the present cluster computer would be extended to develop a virtual private network (VPN) server for clustering the computer present at the different geographical locations and data mining.

In this paper, we demonstrate a hardware implementation of Kalman filter to enhance accuracy in the measurements of time-of-flight in an ultrasonic pulse echo technique (operated at 10 MHz). Pulser-receivers and other respective circuit units are designed using off-the-shelf electronic components. The advanced reduced instruction-set computing machine processor based Raspberry Pi single board computer is used to implement the Kalman filter and control various processes. Additionally, a graphical user interface is designed using Qt software, under the Debian open source operating system. The software has capability to measure and display the time-of-flight and ultrasonic propagation velocity in a liquid under test. The designed system with the Kalman filter exhibited an extremely small error of about 0.01% in the time-of-flight measurements compared with other systems. The functionality of the developed approach to measure time of flight and thereby ultrasonic velocity with significant improvement has been discussed in this article. It was experimentally verified that by improving other parameters such as the separation between the transducer and the reflector and cell structure, significant improvement in the accuracy of ultrasonic velocity in the liquid under test is achieved.

Using zinc nitrate as a precursor and NaOH starch as a stabilizing agent, hexagonal zinc oxide (ZnO) nanoparticles has been synthesized by precipitation method. The transmission electron microscopy (TEM) images show particles of nearly uniform spherical size of around 40 nm. The infrared spectroscopy (FT-IR) measurement reveals the peak at 500 cm −1 , corresponding to the Zn–O bond. Dielectric studies of ZnO nanoparticles show frequency dependence dielectric anomaly at low temperature (85–300 K). Results reveal that the capacitance and loss tangent decrease with the frequency while these parameters improve with the increasing of temperature. The increase of a.c. conductivity with the temperature indicates that the mobility of charge carriers is responsible for hopping and electronic polarization in ZnO nanoparticles.

Well defined, dense, hollow spheres of anatase titania (TiO 2 ) nanoparticles were produced from TiCl 4 (as precursor) by diffusion flame technique. Flow rates of gases (LPG/air/N 2 compositions) were found to affect particle size. Titania nanoparticles were observed to decrease from 19 to 8 nm when the air flow rates were increased from 20 to 25 lpm. However, the particle size was found to increase from 15 to 21 nm when the nitrogen flow rate was increased from 0.8 to 2.0 lpm. LPG has been used as fuel. The increase in particle size of anatase TiO 2 was due to higher flame height and temperature. The anatase (TiO 2 ) phase was predominant compare to rutile phase in the ratio of 74:26 using air as an oxidant. In the gas phase reaction, the nanoparticles formation occurs due to spontaneous increase of number density of nuclei. The coagulation or aggregation of particles leads to the formation of larger particles due to higher chances of collisions among the particles and sintering at high flame temperature.

NiFe2O4 nanoparticles have been synthesized by co-precipitation method at 145°C in N2 atmosphere using ethylene glycol as solvent and capping agent. This gives the promising synthesis route for nanoparticles at low temperature. The as-synthesized NiFe2O4 is subsequently heated at 400°C, 500°C, 700°C and 800°C. Crystallite size increases with the heat treatment temperature. The heat treatment temperature has direct effect on the electron paramagnetic resonance and intrinsic magnetic properties. The room temperature Mossbauer spectrum of the 800°C heated sample shows the two sextets pattern indicating that the sample is ferrimagnetic and Fe3 + ions occupy both tetrahedral and octahedral sites of spinel structure.

Ultrafine particles of Co1 − x Li x Fe2O4 (x = 0, 0.2) samples are prepared by glycine–nitrate combustion route. X-ray diffraction and transmission electron microscopy studies show that the samples have cubic spinel structure and average crystallite sizes of x = 0 and 0.2 are 36 and 44 nm respectively. Vibrating sample magnetometer studies revealed the ferromagnetic nature of the samples. Li-doped CoFe2O4 sample showed higher values of coercive field, remanent magnetization and saturation magnetization compared to pure CoF2O4 indicating the enhancement of magnetic interactions. Mossbauer spectra at 77 K exhibited two broad sextets indicating that Fe3 + ions occupy both tetrahedral and octahedral sites. From these studies, it is concluded that Co1 − x Li x Fe2O4 (x = 0, 0.2) samples exhibit an inverse spinel structure. At room temperature, two sextets are superimposed on a very broad non-Lorentzian background indicating the presence of superparamgnetic fraction in agreement with the microscopic observations.

Re-dispersible CdS, 5 at.% Eu3+-doped CdS, 2 at.% Li+ and 5 at.% Eu3+ co-doped CdS nanoparticles in organic solvent are prepared by urea hydrolysis in ethylene glycol medium at a low temperature of 170°C. CdS nanoparticles have spherical shape with a diameter of ∼80 nm. The asymmetric ratio (A 21) of the integrated intensities of the electrical dipole transition to the magnetic dipole transition for 5 at.% Eu3+-doped CdS is found to be 3.8 and this ratio is significantly decreased for 2 at.% Li+ and 5 at.% Eu3+ co-doped CdS (A 21 = 2.6). It establishes that the symmetry environment of Eu3+ ion is more favored by Li-doping. Extra peak at 550 nm (green emission) could be seen for 2 and 5 at.% Eu3+ co-doped CdS. Also, the significant energy transfer from host CdS to Eu3+ is found for 5 at.% Eu3+-doped CdS compared to that for 2 at.% Li+ and 5 at.% Eu3+ co-doped CdS.

Several researchers have reported numerous measurements on ultrasonic velocity as a function of temperature and pressure using various experimental techniques. A large amount of experimental data is required in order to obtain accurate results for the chemical substances used. The present article explores the evaluation of ultrasonic velocity as a function of molecular weight, temperature and pressure using an artificial neural network (ANN) in six refrigerants. The network so developed predicts the ultrasonic velocity successfully. Statistical analysis of the results was performed using standard deviation (%) and relative average deviation. The correlation coefficient in our analysis was found to be 0.9999. The trained weights, obtained from ANN, are further employed to form equations to predict ultrasonic velocity at other temperatures and pressures.

This study at the Church of Nossa Senhora do Pilar, built in 1613 by the Spanish Capuchos Franciscan, investigates the acoustic effect of music on the subjective comfort of a listener in a wor-ship space. The results presented describe the effect of variations in the type of music rendered (in the form of live music from the cello, clarinet and the ensemble) from two music sources sites (the nave and the choir loft, of the church) on the subjective acoustic comfort of listeners in the church of Nossa Senhora do Pilar (a significant Catholic church of Goa, India). The subjective acoustic comfort of the listeners for different music types at the two music sources was measured through the Acoustic Comfort Impression Index (ACII). This index for subjective acoustic comfort was de-rived as a difference between desirable Subjective Acoustic Impressions such as of Intimacy, En-velopment, Reverberance, Loudness, Clarity, Directionality, Balance and undesirable Subjective Acoustic Impressions such as of Echoes and of Background Noise. The derived acoustic comfort impression index also took into account the requisite of reverential awe; intelligibility for sacred speech, music, singing and the sacred silence that characterizes a worship space. Although the sa-cred music rendered by the ensemble seems to have elicited better scores of Acoustical Comfort Impression Index (ACII) among the listeners, yet there is no significant difference between the means of the listeners acoustical comfort impressions by the ensemble, cello or clarinet (p = 0.43). Amongst the two music source locations, although the Acoustical Comfort Impression Index (ACII) seems to favor the choir loft location, the music rendered therein is only 80% significantly more effective than the music rendered from the nave floor location (p = 0.20).

Acoustic Silence, Acoustic Intelligibility and Acoustic Sacred Factor are the acoustically constituted determinants of tranquillity in a Catholic church. The results presented here are part of a study that investigates the behaviour of derived acoustic parameters in worship spaces. Acoustically, Silence Factor (SiF) is found to decay quadratically with LAeq (R2=0.95, p

Acoustic Comfort and Acoustic Silence are determinants of tranquility in a worship space. The results presented here are part of a study that investigates the behaviour of acoustically constituted worship parameters in six Catholic churches (Goa, India). Acoustic comfort is quantified through an Acoustic Comfort Impression Index which measures the net comfort induced through the optimization of the desired subjective acoustic impressions for different types of music and different music sources. Silence Factor is constituted through the normalization of equivalent noise level (LAeq) and the subjective acoustic impressions of background noise and echoes. Regression analyses of the derived acoustic parameters generate significant results. Acoustically, the Silence Factor quadratically decays with LAeq and the Acoustic Comfort Impression Index is predicted as a multiregression on the subjective acoustic impressions of balance and clarity. Architecturally, the Silence Factor linearly grows with the width of the nave (of the church) whereas, the Acoustic Comfort Impression Index does not significantly relate with any of the tested architectural parameters. Silence Factor was found to linearly grow with Acoustic Comfort Impression Index in a church. The predictability of acoustic comfort and acoustic silence from acoustic and architectural measures can be developed into a design tool for the prediction of a tranquility factor in worship spaces.

The results presented here are based on field measurements carried out in six Catholic churches (Goa, India). Rapid Speech Transmission Index ( RASTI) and Subjective Speech Intelligibility ( SSI) measurements were made in four different seating zones of a church for three speech source locations (altar, pulpit, high altar), two languages (English, Konkani) and two postures (standing, sitting). The effects of language and postures were not significant. The altar location and the sanctuary of the church were preferable for speech intelligibility. Although the altar location showed better averages than the other speech source locations, the best predictive relationship between RASTI and SSI was the exponential growth of RASTI for the high altar source location with SSI for the English language.

Co1 − x Ag x Fe2O4 nanoparticles have been prepared by the combustion route. The average crystallite sizes for compositions with x = 0 and 0.2 are found to be 36 and 33 nm respectively from the XRD line broadening. Compared to the pure CoFe2O4, Ag-doping reduces the intrinsic magnetization values (M, M r), but enhances coercivity (H c). Mossbauer spectra show two sextets, indicating occupancies of tetrahedral and octahedral sites by Fe3 + . Hyperfine fields of 505 and 477 kOe in pure CoFe2O4 have been found for octahedral and tetrahedral sites respectively at liquid nitrogen temperature. The hyperfine field decreases with Ag-doping which also corroborates the magnetization studies. EPR study confirms the room temperature ferromagnetic behavior for Co1 − x Ag x Fe2O4 (x = 0.2). The room temperature Mossbauer studies on x = 0.0 and 0.2 show the ferromagnetic sextets (95%) along with superparamagnetic doublet (5%). However, x = 0.6 sample shows the ferromagnetic sextets only at room temperature. Highly Ag doped samples could be useful for the fabrication of the high-density magnetic materials as well as magnetic drug delivery.

Nanoparticles of Sn1−xFexO2 (x = 0, 0.02, 0.05, 0.1) have been prepared by co-precipitation method using SnCl2 and FeSO4 precursors and subsequent heat-treatment at 600°C. X-ray Diffraction (XRD) study shows that these nanoparticles crystallise in tetragonal system. The unit cell volume increases slightly with Fe2+ doping indicating substitution of Sn4+ sites by Fe2+ ions. The unit cell volume increases from 72.24 A3 to 72.90 A3 as x varies from 0 to 0.1. With increasing Fe2+ concentration, the peaks in X-ray diffraction pattern become broad because of strain effect produced from substitution of smaller ionic radius Sn4+ (0.69 A) by large one Fe2+ (0.77 A). The average crystallite size was found to decrease from 21 nm to 11 nm as x changed from 0 to 0.1. In Transmission Electron Microscopy (TEM) study of pure SnO2, the particles are spherical in shape and particle size is found to be 25 nm, which is close to 21 nm from XRD study. Its Selected Area Electron Diffraction (SAED) confirms the tetragonal system. In infrared study, a broad peak centred around 650 cm1− was observed due to Sn-O/Fe-O vibration. From steady state luminescence study, it is found that pure SnO2 and Fe2+ doped SnO2 show the band-edge emission around 400 nm and the emission intensity decreases with increasing Fe2+ concentration. The band-edge absorption occurs in 300-350 nm.