The development of a health monitoring scheme for complex rotary machines using unlabeled and imbalanced multivariate data is a well-recognized challenging problem. The challenges and complexity ...further increase when the health of the machine degrades over time. In order to utilize unlabeled and imbalanced multivariate degradation data, this paper develops an intelligent health monitoring scheme for rotary machines based on the proposed adaptive fuzzy c -means clustering algorithm followed by ensemble learning, mean-variance-based samples generation method, and 1-D convolutional neural network. The adaptive fuzzy c -means clustering algorithm uses nondominated sorting genetic algorithm II to automatically determine the different health state labels from unlabeled degradation data. The principle of ensemble learning is used to increase the robustness of the obtained health state labels. Further, based on obtained health states, a new solution is presented to construct the true remaining useful life adaptively. The proposed framework presents a novel method for generating samples based on mean-variance to deal with imbalanced health states. Furthermore, an architecture of 1-D convolutional neural networks for multivariate data is designed to predict the health states and remaining useful life of rotary machines. The proposed approach has been validated through aero-engine and XJTU-SY bearing datasets. The health state prediction accuracy is as high as 99.97% and 100% for aero-engine and XJTU-SY datasets, respectively, using the proposed scheme. The results and comparative studies show the effectiveness of the proposed scheme.
The diverse morphologies of primary cilia are tightly regulated as a function of cell type and cellular state. CCRK- and MAK-related kinases have been implicated in ciliary length control in multiple ...species, although the underlying mechanisms are not fully understood. Here, we show that in C. elegans, DYF-18/CCRK and DYF-5/MAK act in a cascade to generate the highly arborized cilia morphologies of the AWA olfactory neurons. Loss of kinase function results in dramatically elongated AWA cilia that lack branches. Intraflagellar transport (IFT) motor protein localization, but not velocities, in AWA cilia is altered upon loss of dyf-18. We instead find that axonemal microtubules are decorated by the EBP-2 end-binding protein along their lengths and that the tubulin load is increased and tubulin turnover is reduced in AWA cilia of dyf-18 mutants. Moreover, we show that predicted microtubule-destabilizing mutations in two tubulin subunits, as well as mutations in IFT proteins predicted to disrupt tubulin transport, restore cilia branching and suppress AWA cilia elongation in dyf-18 mutants. Loss of dyf-18 is also sufficient to elongate the truncated rod-like unbranched cilia of the ASH nociceptive neurons in animals carrying a microtubule-destabilizing mutation in a tubulin subunit. We suggest that CCRK and MAK activity tunes cilia length and shape in part via modulation of axonemal microtubule stability, suggesting that similar mechanisms may underlie their roles in ciliary length control in other cell types.
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•DYF-18 CCRK and DYF-5 MAK kinases regulate cilia length and branching•Axonemal microtubules (MTs) are stabilized upon loss of kinase function•Destabilizing MTs can partly restore cilia length and branching in kinase mutants•These kinases modulate MT dynamics in multiple cilia types in C. elegans
Cilia are microtubule-based organelles that exhibit cell-specific morphologies. CCRK- and MAK-related kinases restrict cilia length in multiple organisms. Maurya et al. show that a CCRK and a MAK kinase act in a cascade to control cilia shape and structure by regulating axonemal microtubule dynamics in multiple sensory neuron types in C. elegans.
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•Dioxidomolybdenum(VI) and Dioxidouranium(VI) complexes are reported.•All complexes are well characterised.•X-ray single crystal structure of dioxidouranium(VI) complex is ...reported.•These complexes are good catalysts for the oxidative bromination of thymol.
The stable dibasic tetradentate ligand 1,4-bis-(2-hydroxy-3,5-dimethylbenzyl)piperazine (H2pip-2,4-dmp, I) prepared by reacting 2,4-dimethylphenol with piperazine in the presence of formaldehyde reacts with MoVIO2(acac)2 and UVIO2(CH3COO)2 in equimolar ratio to give neutral hexa-coordinated MoVIO2(pip-2,4-dmp) (1) and hepta-coordinated UVIO2(pip-2,4-dmp)(MeOH) (2), respectively. After characterizing these complexes by spectroscopic (IR, UV/Vis, 1H and 13C NMR) data, elemental and thermal analyses (and single crystal X-ray diffraction study of uranium complex), they are used as catalysts to study the oxidative bromination of thymol. Such catalytic reactions are observed by many model vanadium complexes and are considered as a functional mimic of haloperoxidases. The catalytic oxidation resulted in the formation of three products namely, 2-bromothymol, 4-bromothymol and 2,4-dibromothymol. The optimized reaction conditions are obtained considering concentration of KBr, HClO4, and oxidant for the maximum yield of brominated products. Under the optimized reaction conditions, the product selectivity for both the prepared complexes is investigated. They are found to be competent homogeneous catalysts to afford the products in good yield.
Electronic and thermoelectric properties of cubic cuprous oxide are investigated from the LAPW method. The calculations are performed taking the generalized gradient approximation together with ...Hubbard U scheme at the level of density functional theory. After settling the crystal structure, partial and total density of states are calculated. The Kohn-Sham eigenvalues spectra from the first-principles calculations are interfaced with the Boltzmann transport equations to find transport coefficients. This is achieved by coupling the E-k spectrum from LAPW method with the BoltzTraP. A number of transport coefficients namely, the Seebeck coefficient, power factor, electrical conductivity are reported utilizing GGA and the GGA+U approaches. The effect of temperature and doping on these transport coefficients is discussed. Our results are in better agreement with experimental results than the other theoretical calculations. The results eloquently demonstrate that the LAPW method embodied in the ElK can be deployed in conjunction with the BoltzTraP to investigate thermoelectric properties of other transition metal compounds.
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•E-k spectra from ElK are interfaced with BoltzTraP to find transport coefficients.•The ElK-BoltzTraP link can be used to study transport properties of other materials.•Effect of U is clearly visible on the DOS and thermoelectric properties.•The scissor correction in GGA improves values of the thermoelectric coefficients.•Calculations agree with the available measurements better than earlier studies.
The CMOS compatible bulk micromachined piezoresistive accelerometer presented in this paper consists of four flexures supporting a proof mass. Four pairs of boron-diffused piezoresistors are located ...at maximum stress points on the flexures near the proof mass and frame ends. Because of the opposite nature of stress at the two ends, these piezoresistors can be connected to form a Wheatstone bridge such that the off-axis responses are practically cancelled while the on-axis (along perpendicular to proof mass) response is maximized. The device is simulated using CoventorWare. In the fabrication process, dual-doped TMAH solution is used for wet anisotropic etching. The novelty of this etching process is that the bulk micromachining can be performed after aluminum metallization. The etched surface is also smooth. The fabrication is thus CMOS compatible. The accelerometer exhibits good linearity over 0–10g.
•ANN model corrected flow stress of WAAM Ti-6Al-4V alloy used to construct processing map.•The self deformation activation energy were significantly different in the α+β and β phase region.•The high ...fraction and nearly equiaxed DRX α obtained at the high efficiency region of the processing map.•The hot forged sample at optimum condition show weak texture, high strength and elongation.
Recently, the hybrid method has been developed in which wire and arc additive manufacturing (WAAM) use to produce the near net shape preform for the single-step hot forging process. The hybrid method overcomes the defects and anisotropic properties of WAAM processed preform and produce the net shape of the component with better mechanical properties. This study investigates the hot deformation behavior and mechanical properties of WAAM Ti-6Al-4V alloy containing widmantatten microstructure (0.34 – 0.48 µm) produced by the hybrid method. Hot deformation tests were conducted in the temperature range 700–1000 °C and strain rate range 0.01 s−1 – 10 s−1 up to the height reduction of 60%, using the thermal-mechanical simulator gleeble-3800. The artificial neural network model (ANN) has been developed to correct the non-isothermal flow curve at finer intervals of experimental conditions. The microstructural studies were carried out at various regions using a developed processing map. The microstructures show an instability region at a high strain rate and lower temperature, associated with flow localization and lamellae kinking. At the same time, the high efficiency and stable regions are related to dynamic recrystallization in the temperature range 900–950 °C at a strain rate below 1 s−1. The self-deformation activation energy in the α + β and β phase regions was 308.7 kJ/mol and 493.2 kJ/mol, respectively. The forged sample at 920 °C and strain 0.6, 0.8, and 0.9 show high strength, elongation, and weak texture compared to the received and stress relieved sample.
We report on high-responsivity metal-semiconductor-metal (MSM) structure based ultraviolet (UV) GaN photodetectors fabricated on various GaN nanostructures such as porous nanocolumn network (PNCN), ...nanowall networks (NWNs), and granular and compact thin films. Different GaN nanostructures were hetero-epitaxially grown on c-sapphire using laser molecular beam epitaxy by tuning the AlN buffer layer growth parameters. High resolution x-ray rocking curve measurements indicate that the crystalline quality of GaN critically depends on the selection of AlN buffer layer growth conditions such as type of ablation target and growth temperature. The porous GaN nanostructures revealed a nearly stress-free wurtzite structure as deduced by Raman spectroscopy measurements. Room temperature photoluminescence spectroscopy showed that the GaN films possess a near band emission (NBE) peak at ∼ 3.39 eV along with a broad yellow luminescence (YL) with maxima at 2.25 eV. For GaN PNCN and NWN structures, the NBE-to-YL emission ratio is more than an order higher compared to the GaN films. The fabricated MSM based UV-detector on GaN PNCN and NWN exhibited a high photo-responsivity of ∼27.72 and 24.8 A/W, respectively, under 2 V applied bias at room temperature. The GaN PNCN and NWN nanostructures with excellent photo-responsivity and optical quality prove to be promising candidates for the fabrication of efficient UV photodetectors due to their continuity in lateral direction, high surface area-to-volume ratio and tailored surfaces.
•Laser molecular beam epitaxy of Porous GaN nanostructures on c-sapphire.•Tuning of shape and size of GaN nanostructures with AlN growth parameters.•Formation of GaN porous nanocolumn network (PNCN) and nanowall network (NWN) structures.•Fabrication of metal-semiconductor-metal based GaN UV photodetectors.•Achievement of a high UV responsivity of 27.72 A/W for GaN PNCN photodetectors.
We have presented a new anisotropic solution of Einstein's field equations for compact star models. The Einstein's field equations are solved by using the class one condition \cite{1}. After that we ...constructed the physically valid expression of anisotropy factor by the help of metric potentials and there after we obtained the physical parameters like energy density, radial and transverse pressure. These models parameters are well behaved inside the compact star and satisfy all the required physical conditions. Also we observed a very interesting result that all the physical parameters are depend on the anisotropy factor. The present compact star models are quite compatible with the observational astrophysical compact stellar objects like Her X-1, RXJ 1856-37, SAX J1808.4-3658(SS1), SAX J1808.4-3658(SS2)
A solution-processable small-molecule nonfullerene electron acceptor BAF-2HDT (7,7′-(9,9-didecyl-9H-fluorene-2,7-diyl)bis(4-((4,5-bis(hexylthio)-1,3-dithiol-2 ...ylidene)methyl)benzoc1,2,5thiadiazole) bearing hexadiathiafulvalene (HDT) wings as end groups has been synthesized for bulk heterojunction organic photovoltaics. The molecule shows broad absorption in the 300–600 nm range with a molar extinction coefficient (ε) of 9.32 × 104 M–1·cm–1 exceeding to that of 6,6-phenyl-C71-butyric acid methyl ester of 2.8 × 104 M–1·cm–1 at 461 nm. The HOMO and LUMO energy levels of the molecule are found to be −5.69 and −3.58 eV, respectively which is compatible with low band gap high-performance polymers such as poly(5,6-difluoro-2,1,3-benzothiadiazol-4,7-diyl)-alt-(3,3‴-di(2-octyldodecyl)-2,2′;5′,2″;5″,2‴-quaterthiophen-5,5‴-diyl) (PffBT4T-2OD). Photoluminescence-quenching measurements confirm that the molecule BAF-2HDT has excellent electron-accepting capability. The organic solar cells made from BAF-2HDT blending with conjugated polymer donor PffBT4T-2OD exhibit a power conversion efficiency of 7.13% with high V oc of 0.77 V, J sc of 14.64 mA·cm–2, and FF of 0.64. The design and development of such nonfullerene acceptors with high ε may be key to further development of high-performance and cost-effective solution-processed organic solar cells.
Functional assessments of cardiovascular fitness (CVF) are needed to establish animal models of dysfunction, test the effects of novel therapeutics, and establish the cardio-metabolic phenotype of ...mice. In humans, the graded maximal exercise test (GXT) is a standardized diagnostic for assessing CVF and mortality risk. These tests, which consist of concurrent staged increases in running speed and inclination, provide diagnostic cardio-metabolic parameters, such as, VO2max, anaerobic threshold, and metabolic crossover. Unlike the human-GXT, published mouse treadmill tests have set, not staged, increases in inclination as speed progress until exhaustion (PXT). Additionally, they often lack multiple cardio-metabolic parameters. Here, we developed a mouse-GXT with the intent of improving mouse-exercise testing sensitivity and developing translatable parameters to assess CVF in healthy and dysfunctional mice. The mouse-GXT, like the human-GXT, incorporated staged increases in inclination, speed, and intensity; and, was designed by considering imitations of the PXT and differences between human and mouse physiology. The mouse-GXT and PXTs were both tested in healthy mice (C57BL/6J, FVBN/J) to determine their ability to identify cardio-metabolic parameters (anaerobic threshold, VO2max, metabolic crossover) observed in human-GXTs. Next, theses assays were tested on established diet-induced (obese-C57BL/6J) and genetic (cardiac isoform Casq2-/-) models of cardiovascular dysfunction. Results showed that both tests reported VO2max and provided reproducible data about performance. Only the mouse-GXT reproducibly identified anaerobic threshold, metabolic crossover, and detected impaired CVF in dysfunctional models. Our findings demonstrated that the mouse-GXT is a sensitive, non-invasive, and cost-effective method for assessing CVF in mice. This new test can be used as a functional assessment to determine the cardio-metabolic phenotype of various animal models or the effects of novel therapeutics.
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