Epsilon‐shaped circularly polarized strip and slot‐loaded ultra‐wideband antenna for Ku‐band and K‐band

A compact epsilon‐shaped (ε) ultra‐wideband (UWB) antenna for dual‐wideband circularly polarized (CP) applications has been investigated in this article. It consists of a stepped stub loaded modified annular ring‐shaped radiator and modified CPW ground plane. The ground plane is loaded with two semicircular notches and a spiral‐shaped slot. The impedance bandwidth (IBW) is 97.02% (10.4‐30 GHz) along with an overall footprint of 20 × 20 mm². The fractional axial ratio bandwidth (3‐dB ARBW) for two wide bands is 38.50% (13.30‐19.64 GHz) and 6.45% (26.25‐28.00 GHz), respectively. The proposed antenna is left‐hand circularly polarized with a peak gain of about 5.09 and 5.14 dB in both 3‐dB ARBW bands. The proposed antenna is dominating other reported CP antenna structures in terms of number of CP bands, 3‐dB ARBW, IBW, peak gain, and dimensions.     

A micro level study of an Indian electric utility for efficiency enhancement

In this paper DEA (Data envelopment analysis), a non-parametric approach to frontier analysis, is applied to evaluate the relative performance of 29 EDDs (Electricity Distribution Divisions) of an Indian hilly state, namely Uttarakhand. Input oriented DEA is applied to evaluate the relative overall efficiency, technical efficiency and scale efficiency of EDDs. The results indicate that numerous divisions have scope for improvement in overall efficiency. Most of the utilities are inefficient due to their scale inefficiency rather than technical inefficiency. Further Slack analysis is carried out to formulate improvement directions for relatively inefficient divisions. Particular areas are identified, which are to be improved for overall efficiency enhancement through sensitivity analysis. Different alternatives for reorganization of the EDDs are explored in order to obtain most favorable and balanced scale. The result is envisaged to be instrumental to policy makers and managers to increase the operational efficiency of the EDDs leading to higher profitability of the state electricity board.     

Discrete Wavelet Transform Based Measurement of Inner Race Defect Width in Taper Roller Bearing

Local bearing defect monitoring and measurement has been a challenging area of research for profitable use of motion. A technique based on decomposition using Symlet wavelet is implemented for measuring inner race defect width in a taper roller bearing. It is difficult to estimate the defect width in inner race because defect moves continuously with respect to accelerometer. The bursts are selected from the signal for measuring the defect width on the basis of their amplitude. The degree of ambiguity in detecting the entry point in the groove gets reduced by using Symlet5 wavelet based decomposition which is almost linear phase nature and hence, sharpness in the signal gets maintained even in case of sudden change induced in raw signal. The technique has been successfully implemented for measuring defect width ranging from 0.4714 to 1.8145 mm. The measurement of defect width has also been verified by image analysis. Maximum difference in measurements has been found to be 6.68 % for the defect width of 0.4714 mm at no load condition and this gets reduced to 1.21 % with increase in load. This method has also potential in dimension measurement of surfaces having dissimilar and uneven surface characteristics.     

Experimental observation of the effect of astigmatic aperture lens on the spectral switches of polychromatic Gaussian beam

Experimental results of a study, conducted to investigate the effect of an astigmatic aperture lens on the spectral switches observed with spatially coherent polychromatic light, are reported. It is found that the spectrum at the observation plane exhibits anomalous behavior after passing through the astigmatic aperture lens. It is shown that at a particular position of the aperture, the spectrum splits into two halves, while at other positions the spectrum either shifts towards lower frequencies (red shift) or shifts towards higher frequencies (blue shift). These spectral changes take place in the vicinity of the dark region of the diffraction pattern. Experimental observations show that the behavior of the spectral switch is affected by the astigmatism of the lens. It is found that the spectral minimum value and the transition height of the spectral switch change as the astigmatism of the lens changes. Moreover, the critical position of the aperture where spectral switch occurs also changes with the astigmatism of the lens. The results are consistent with the theoretical predictions [Pan, L.; Lü, B. Opt. Commun. 2004, 234, 13–22].     

Soft-computing-based approaches to the group technology problem: A state-of-the-art review

This paper presents a state-of-the-art review synthesizing the literature on the use of soft-computing-based approaches, e.g. neural networks and fuzzy models to the group technology problem. The objectives of this paper are to discuss the trend and to identify the gaps for performing future research in this area.     

Effect of Calcium Doping on Dielectric and Pyroelectric Properties of PLZT

Effect of calcium doping on structural, dielectric and pyroelectric properties of Pb_0.92-xLa_0.08Cax(Zr0.65Ti0.35)_0.98O₃ (PLCZT) composition derived by the solid state reaction method was studied. Rhombohedral perovskite phase was confirmed in all the PLCZT samples. Calcium doping did not show any structural change in PLCZT (8/65/35) up to 2.5 % doping, however grain size and crystallite size was found to increase up to 1%, but no systematic variation of transition temperature was found with Ca doping. P-E hysteresis loop parameters (E_c and P_r) and pyroelectric properties were found to decrease with Ca doping up to 1% and there after increased.     

Least squares best fit line method for the evaluation of measurement uncertainty with electromechanical transducers (EMT) with Electrical Outputs (EO)

In the electromechanical type indirect pressure indicating devices (IPIDs), the applied pressure is indirectly computed by some relationship between applied pressure and an analog / digital electrical signal in terms of voltage, current or frequency measured by a sensing element of such devices. If the output of an EMT in terms of any electrical quantity i.e. voltage, current or frequency, is related / dependent upon input quantity i.e. pressure then this relationship can be defined by a curve that has been fitted to experimental data by method of least square. The calculation of the calibration results and the associated uncertainties is a complex matter involving many influencing quantities. The present paper describes a method for calibration and evaluating uncertainty in pressure measurement using such EMTs with EOs through statistical analysis of errors.     

Evolution of atomic and electronic structure of magnetic Gd-doped gold clusters

The evolution of atomic and electronic structure of small Au _n (n = 1–16, and 55) clusters doped with a Gd atom has been investigated using density functional theory within generalized gradient approximation for the exchange–correlation energy. Pure gold neutral clusters with n up to 15 are planar. However, with the doping of a Gd atom, the atomic structure of gold clusters changes, and there is a transition from planar-like structures to three dimensional structures at n = 10. The electronic structure of Gd-doped gold clusters shows a sharp increase in the highest occupied–lowest unoccupied molecular orbital (HOMO–LUMO) gap for certain sizes giving rise to their magic behavior. All clusters are magnetic with large magnetic moments ranging from 6 to 8 μ_B primarily due to the localized 4f electrons on Gd. This makes such clusters with large HOMO–LUMO gaps magnetic superatoms. The main interaction between gold and gadolinium atoms in the clusters is due to hybridization between Au-6s and Gd-5d6s orbitals. Our results indicate the emergence of a wheel structure for Gd@Au₇, a symmetric cage structure at n = 15 for Gd@Au₁₅ and n = 16 for Gd@Au₁₆ ⁺ and Eu@Au₁₆ corresponding to an electronic shell closing at 18 valence electrons leaving aside the f electrons on Gd while for Gd-doped Au₅₅ corresponding to 58 valence electrons, a Au₉Gd@Au₄₆ core–shell structure is obtained in which the Gd atom connects the core of Au₉ with the Au₄₆ shell. The binding energy shows odd–even oscillations with enhancement due to Gd doping compared with pure gold clusters. Such magnetic clusters of gold could have multifunctional biological applications in drug delivery, sensor, imaging, and cancer treatment.     

In-Silico Evaluation of Genetic Alterations in Ovarian Carcinoma and Therapeutic Efficacy of NSC777201, as a Novel Multi-Target Agent for TTK,NEK2, and CDK1

Ovarian cancer is often detected at the advanced stages at the time of initial diagnosis. Early-stage diagnosis is difficult due to its asymptomatic nature, where less than 30% of 5-year survival has been noticed. The underlying molecular events associated with the disease’s pathogenesis have yet to be fully elucidated. Thus, the identification of prognostic biomarkers as well as developing novel therapeutic agents for targeting these markers become relevant. Herein, we identified 264 differentially expressed genes (DEGs) common in four ovarian cancer datasets ({"type":"entrez-geo","attrs":{"text":"GSE14407","term_id":"14407"}}GSE14407, {"type":"entrez-geo","attrs":{"text":"GSE18520","term_id":"18520"}}GSE18520, {"type":"entrez-geo","attrs":{"text":"GSE26712","term_id":"26712"}}GSE26712, {"type":"entrez-geo","attrs":{"text":"GSE54388","term_id":"54388"}}GSE54388), respectively. We constructed a protein-protein interaction (PPI) interaction network with the overexpressed genes (72 genes) and performed gene enrichment analysis. In the PPI networks, three proteins; TTK Protein Kinase (TTK), NIMA Related Kinase 2 (NEK2), and cyclin-dependent kinase (CDK1) with higher node degrees were further evaluated as therapeutic targets for our novel multi-target small molecule NSC777201. We found that the upregulated DEGs were enriched in KEGG and gene ontologies associated with ovarian cancer progression, female gamete association, otic vesicle development, regulation of chromosome segregation, and therapeutic failure. In addition to the PPI network, ingenuity pathway analysis also implicate TTK, NEK2, and CDK1 in the elevated salvage pyrimidine and pyridoxal pathways in ovarian cancer. The TTK, NEK2, and CDK1 are over-expressed, demonstrating a high frequency of genetic alterations, and are associated with poor prognosis of ovarian cancer cohorts. Interestingly, NSC777201 demonstrated anti-proliferative and cytotoxic activities (GI₅₀ = 1.6 µM~1.82 µM and TGI₅₀ = 3.5 µM~3.63 µM) against the NCI panels of ovarian cancer cell lines and exhibited a robust interaction with stronger affinities for TTK, NEK2, and CDK1, than do the standard drug, paclitaxel. NSC777201 displayed desirable properties of a drug-like candidate and thus could be considered as a novel small molecule for treating ovarian carcinoma.