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Ball bearing is used to provide free rotation around a fixed axis. Various kinds of faults exist in the bearing such as inner race fault, outer race fault and ball race fault. One very effective method to diagnose the bearing fault is vibration signal analysis. Empirical mode decomposition (EMD) has been used for ball-bearing fault diagnosis in mechanical systems using vibration signal analysis. Classification of the ball-bearing fault has always been a challenging task. Various classification schemes such as Extreme learning machine (ELM), K-means Clustering, and Support vector machine (SVM), have been reported in the literature for ball-bearing fault classification. SVM is restricted by multiclass classification efficiency, and ELM is restricted by the longer training. In this paper, the entropy analysis of the wavelet coefficient obtained from the third level decomposition of the residue signal (obtained after subtracting the highest frequency component from the raw signal) has been done for ball-bearing fault classification. A comparative analysis of the wavelet coefficient based on entropy measurement has been presented here. High fault classification accuracy has been achieved using the proposed method for the detection of ball-bearing fault. Shannon entropy, Average Shannon entropy, and Renyi's entropy are parameters for the justification of the proposed approach. The result shows the best wavelet to be chosen among the available discrete wavelet based on various entropy measurements. [ABSTRACT FROM AUTHOR]

The potential of Indian propolis as a suitable therapeutic agent is still to be explored to the fullest. As variation in the chemical composition across different geographical regions has been a major concern, it is, therefore, worthwhile to systematically investigate, and assess the quality of Indian propolis and set nationalized standards. The propolis collected from three different regions were authenticated for the major plant source, followed by the evaluation of physicochemical properties. Different extraction methods were compared, with their influence on balsam content, polyphenol, and flavonoid content. The sample coded HAR using ultrasonication gave the highest extraction yield of 71.87%. Further, the process variables in the ultrasonication method (i.e. Amplitude, extraction time, the concentration of ethanol) at three levels were optimized using the Box-Behnken response design. The model was found significant with the concentration of ethanol having a maximum influence on the responses. The model was successfully verified by setting the amplitude at 48%, extraction time to 5.6 mins, and ethanol concentration to 87% v/v. The extraction efficiency of 83.86±1.17% was achieved with a substantial diminution of extraction time. The total phenolic, total flavonol, and total flavanone content of the optimized batch were 28.74±0.13 mgGAE/g, 4.66±0.78 mgQE/g, and 3.16±0.14 mgPE/g of propolis respectively. Further HPTLC fingerprint image of the optimized extract revealed the presence of quercetin, p-coumaric acid, kaempferol, chrysin, pinocembrin, and galangin. [ABSTRACT FROM AUTHOR]

Synthesis and crystal structure with extensive biological activity of the copper sulfadimethoxine complex in the presence of secondary ligand 3-methyl pyridine (title molecule) has been reported earlier. Crystal structure of the title molecule crystallizes in monoclinic space group P21/n. The extension of this work, stability, and reactivity of the title molecule are carried out in the DFT platform using Schrödinger software at B3LYP/LAV2P** level. The theoretically optimized structure of the title molecule in gaseous phase is well matched with the X-ray data. The chemical nature of molecule can be analyzed by employing quantum chemical calculations and HOMO-LUMO energies of the title molecule show the charge transfer occurs within the molecule. The individual atomic charge values are obtained from the Mulliken population analysis (MPA), which reveal the binding site of the title molecule. The stability of the title molecule arising from hyper-conjugative interactions and charge delocalization have been analyzed using natural bond orbital (NBO) analysis. The effect of nitrogen and oxygen atoms on weak intermolecular interactions has been systematically analyzed via energy framework analysis for title molecule. The molecular docking study has been confirmed the title molecule interacts with DNA in a groove binding site. [ABSTRACT FROM AUTHOR]

Quantum descriptors of cadmium complex of sulfamethazine and free ligand sulfamethazine are calculated, and the result of these studies has revealed that complex molecule is having high negative dock energy as compared to that of free ligand. Molecular docking studies have been performed against enzyme receptor to rationalize the inhibitory properties of cadmium complex and free ligand. Results demonstrated that metal complexes are stronger inhibitors of protein molecules as compared to free ligand, which warrant further development of organo-metallics as active inhibitors. The author has synthesized and worked out the 3D structure independently to carry out density functional theory studies and Hirshfeld surface analysis of the complex. Cadmium complex of sulfamethazine has been synthesized and characterized by IR and 1H NMR spectroscopy. Antimicrobial activity has been studied with gram-positive and gram-negative bacteria to understand the biological activity of the title molecule and compared with free ligand. [ABSTRACT FROM AUTHOR]

Synthesis of the Ni(II) complex of sulfathiazole was carried out and the crystal structure was determined independently. The various vibration patterns of ligand and its Ni(II) complex are studied by IR spectroscopy. Also, the optimized geometry of the complex is derived from DFT/B3LYP calculations and the results are compared with the experimental one. Bond strengths and first hyperpolarizability of the complex are studied by NBO and NLO analysis, respectively. Also, the molecular properties such as charge transfer are clarified using MPA and FMO analysis. The visualized and correlated in a novel way through qualitative analysis using the Hirshfeld surface and 3 D energy frameworks are performed for the complex. The Ni-STZ complex is studied for the binding properties with CT-DNA employing UV-Vis and viscosity measurement techniques. The molecular docking analyses corroborate well the experimental results of DNA binding. Also, the toxicity of the complex is performed on brine shrimp bioassay. [ABSTRACT FROM AUTHOR]

The synthesis of the compound and its crystal structure having a monoclinic crystal system has been reported earlier. Optimized bond lengths and angles are showing good agreements with experimental data using DFT/B3LYP method. Energy of highest occupied molecular orbital and lowest unoccupied molecular orbital has been predicted to analyze the stabilities of compound. Crystal explorer 17.5 helps to visualize intermolecular interactions and its contributions to each interaction within molecule. The preeminence of dispersion energy component over the other components was established by interaction energy calculations and lattice energy framework analysis using same software. The molecular docking study was performed for molecule using AutoDock software. [ABSTRACT FROM AUTHOR]

Silver complex of 4-Amino-N-(2,6-dimethoxypyrimidin-4-yl)benzenesulfonamide (sulfadimethoxine) have been synthesized and characterized by IR, NMR, PL and UV spectroscopy. Silver complex of sulfadimethoxine crystallizes in monoclinic space group P21/c with lattice parameters: a = 5.9684(4)Å, b = 11.1694(4)Å, c = 22.4716(4)Å, β = 93.48(1)8. The bond lengths and bond angles of crystalline data (X-ray data) are compared with theoretical data in gaseous phase (B3LYP data). Hirshfeld surfaces and consequently the fingerprint analysis have been performed to study nature of interactions and their quantitative contributions towards crystal packing. The stability of a molecule arising from hyper conjugative interactions and charge delocalization has been analyzed using natural bond (NBO) analysis. The calculated HOMO and LUMO energie shows that charge transfer occurs within a molecule. The atomic charge values from the Mulliken population analysis (MPA) and natural population analysis (NPA) have been measured using the B3LYP method. Furthermore, antimicrobial activity of Silver complex of sulfadimethoxine has been studied by dilution method. NLO properties like the dipole moment, polarizability, first static hyperpolarizability have been calculated to get a better cognizance of the properties of the proposed molecule. [ABSTRACT FROM AUTHOR]

Silver complex of sulfapyridine has been synthesized and characterized by IR, NMR and PL. The crystal structure has been determined by X-ray diffraction technique. Silver complex of sulfapyridine with secondary ligand pyridine crystallizes in monoclinic space group P21/n with lattice parameter: a = 17.8075(4)Å, b = 10.7885(3)Å, c = 17.8075(4)Å, β = 94.12(1)Å and Z = 4. To study the nature of intermolecular interactions and their quantitative contributions towards the crystal packing, Hirshfeld surfaces and accordingly the fingerprint plot analysis have been performed. Molecular properties such as NBO analysis, Homo-Lumo energy calculation have been carried out by DFT method. Furthermore, the antimicrobial activity of silver complex of sulfapyridine and free ligand is studied by the dilution method. [ABSTRACT FROM PUBLISHER]

This article presents optimization of large-scale solar photovoltaic plants with economic analysis. The optimization includes the design of the plants, distribution of power conditioning units, and several other factors which affect the performance of the plants throughout their working life. Component arrangements are done to maximize power output and minimize the cost of production under-distributed and the central inverter mode of operation. Several optimization techniques have been analyzed, and a detailed comparison is presented for levelized cost of production and the economics of the plants. Economic analysis of the plants has been investigated to determine the net present value and internal rate of return using the Monte Carlo method. [ABSTRACT FROM AUTHOR]

This article presents an extreme learning machine based fast and accurate adaptive distance relaying scheme for transmission lines in the presence of a static synchronous series compensator. The ideal trip characteristics of the distance relay is greatly affected by pre-fault system conditions, ground fault resistance, and zero-sequence voltage. The proposed research develops an extreme learning machine based adaptive distance relaying scheme for two-terminal transmission networks with static synchronous series compensators when a single-line-to-ground fault situation is most likely to occur. The study includes an analytical approach, including a steady-state model of static synchronous series compensator with detailed simulation on MATLAB/Simulink (The MathWorks, Natick, Massachusetts, USA) and open real-time simulation software with MATLAB (OPAL-RT) platform (OPAL-RT Technologies, Montreal, Quebec, Canada). The proposed extreme learning machine based adaptive distance relaying scheme is extensively validated on the two terminal transmission lines with static synchronous series compensators, and the performance is compared with the existing radial basis feed-forward neural network based adaptive distance relaying scheme. The results on simulation and real-time platform show significant improvements in the performance indices, such as speed, selectivity, and reliability of the digital relay. [ABSTRACT FROM PUBLISHER]

This article presents an adaptive distance relay setting for a power transmission network connecting more than one wind farm. The ideal trip characteristics of the distance relay is greatly affected in the presence of complex mutual coupling of transmission lines, as the apparent impedance is significantly affected. Similarly, the reach setting of the relay for the lines connecting wind farms is significantly affected, as the relaying voltage fluctuates continuously. Thus, the proposed study focuses on developing an adaptive relay setting for a transmission network including more than one wind farm and considering variations in operating conditions of wind farms and mutual coupling of transmission lines together. The proposed relay algorithm is extensively tested on two-terminal as well as multi-terminal power networks with wide variations in operating parameters. The performance testing of the proposed adaptive relay characteristics for faults and faults during power swing indicates the potential ability of the approach in handling distance relaying in a transmission system. [ABSTRACT FROM AUTHOR]

The aim of the report is to document two cases of biopsy-proven temporal arteritis, resulting in major visual loss that recovered almost completely after treatment with intravenous methylprednisolone and intravenous heparin infusion. An 80-year-old Caucasian lady presented with vision of perception of light (PL) due to a central retinal artery occlusion. Following systematic treatment with anterior chamber paracentesis, intravenous heparin, and intravenous steroids, vision improved to 6/5. A definitive diagnosis was made following temporal artery biopsy. A 77-year-old Caucasian lady presented with treated polymyalgia rheumatica, which on further history and examination was confirmed to be temporal arteritis. Prompt treatment of her arteritic anterior ischaemic optic neuropathy with intravenous methylprednisolone and intravenous heparin infusion resulted in improvement of visual acuity from 6/12 to 6/5 with a sustained improvement in visual fields and in the funduscopically visible optic nerve ischaemic changes. The authors conclude that near-complete resolution of major visual loss in these two patients with biopsy-proven temporal arteritis suggests that the appropriate use of a therapeutic intravenous methylprednisolone and heparin protocol could represent a way forward in the management of this potentially blinding disease. This would need to be confirmed in large prospective, randomised controlled studies. [ABSTRACT FROM AUTHOR]

We describe an 82-year-old man who was diagnosed with temporal arteritis (TA) on the basis of a 12-month history of jaw pain and intermittent deafness. The erythrocyte sedimentation rate (ESR) was 80 mm/hr, but there was no thrombocytosis and the patient''s jaw pain did not resolve with steroids. No temporal artery biopsy (TAB) was performed, and the patient went on to develop significant complications of long-term therapy with corticosteroids in the form of mandibular necrosis and fracture, cataracts, and postoperative endophthalmitis. The diagnosis was incorrect. This case stresses that much of the morbidity in TA is from the steroids, especially in the older age group. The diagnostic pathway in TA mandates a comprehensive and accurate history of the disorder, an assessment of its signs, and the performance of an adequate TAB. [ABSTRACT FROM AUTHOR]

Abstract Copper(II) complex of 1-(3-bromo-5-chloro-2-hydroxyphenyl)ethan-1-one has been synthesized and crystallized in solvent pyridine as secondary ligand with monoclinic space group P21/n with set of lattice parameters as a = 14.060(3) Å, b = 12.187(2) Å, c = 15.153(3) Å and β = 91.162(4)° having Z = 4. Molecular geometry around metal is distorted octahedral, and all four oxygen of bidentate ligand co-ordinate to metal forming a square planer configuration along with one nitrogen of each solvent molecule pyridine to complete the octahedral sphere. Crystal packing is governed by various intra–inter molecular, π⋅⋅⋅π, and C-H⋅⋅⋅π interactions. Molecules are linked via C-H⋅⋅⋅X (X = Br) intermolecular hydrogen bond with R 2 2 ( 18 ) motif forming 3D architecture, whereas intramolecular forming S(5) graph set motif such as non-covalent interactions provide fundamental role to design supramolecular architectures, either in organic or metal organic complexes. Computational techniques such as Hirshfeld surface analysis, 3D visualization of intermolecular interactions, and molecular docking studies are incorporated to find best binding affinity with receptors, to explore pharmacological activities of complex. [ABSTRACT FROM AUTHOR]

Abstract The synthesis, optical characterization and crystal structure with biological activity of novel (Z)-2-((3-(4-chlorophenyl)-1-phenyl-1H-pyrazol-4-yl)methylene)-3,4-dihydronaphthalen 1-(2H)-one (Z2H) has been reported. Crystal structure reports with monoclinic system and space group is P21/c. The extension of this work, stability and reactivity are explored using DFT platform with B3LYP[6-11G(d,p)] basic set. Mulliken charge and HOMO–LUMO energy result indicate that the charge transfer within the molecule. The strong and weak intermolecular interactions of Z2H have been systematically analyzed using Hirshfeld surface analysis. Interaction energy are carried out and indicate that the dispersion energy framework is dominated over the electrostatic energy-frameworks. Lipophilicity index (log P value) represents significant biological activity of the molecules. The molecular docking study confirmed good binding affinity of Z2H with DNA (1BNA), 1h3b and 2p4b. [ABSTRACT FROM AUTHOR]