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The stress placed on global power supply systems by the growing demand for electricity has been steadily increasing in recent years. Thus, accurate forecasting of energy demand and consumption is essential to maintain the lifestyle and economic standards of nations sustainably. However, multiple factors, including climate change, affect the energy demands of local, national, and global power grids. Therefore, effective analysis of multivariable data is required for the accurate estimation of energy demand and consumption. In this context, some studies have suggested that LSTM and CNN models can be used to model electricity demand accurately. However, existing works have utilized training based on either electricity loads and weather observations or national metrics e.g., gross domestic product, imports, and exports. This binary segregation has degraded forecasting performance. To resolve this shortcoming, we propose a CNN-LSTM model based on a multivariable augmentation approach. Based on previous studies, we adopt 1D convolution and pooling to extract undiscovered features from temporal sequences. LSTM outperforms RNN on vanishing gradient problems while retaining its benefits regarding time-series variables. The proposed model exhibits near-perfect forecasting of electricity consumption, outperforming existing models. Further, state-level analysis and training are performed, demonstrating the utility of the proposed methodology in forecasting regional energy consumption. The proposed model outperforms other models in most areas. [ABSTRACT FROM AUTHOR]

Abstract: The low temperature fabrication of passive (conductor, capacitor) and active (field effect transistor) electrical components on flexible polymer substrate is presented in this paper. A drop-on-demand (DOD) ink-jetting system was used to print gold nano-particles suspended in Alpha-Terpineol solvent, PVP (poly-4-vinylphenol) in PGMEA (propylene glycol monomethyl ether acetate) solvent, semiconductor polymer (modified polythiophene) in chloroform solution to fabricate passive and active electrical components on flexible polymer substrates. Short pulsed laser ablation enabled finer electrical components to overcome the resolution limitation of inkjet deposition. Continuous argon ion laser was irradiated locally to evaporate the carrier solvent as well as sinter gold nano-particles. In addition, selective ablation of multilayered gold nanoparticle film was demonstrated using the novel SPLA-DAT (selective pulsed laser ablation by different ablation threshold) scheme for sintered and non-sintered gold nanoparticles. Finally, selective ablation of multilayered film was used to define narrow FET (field effect transistor) channel. Semiconductor polymer solution was deposited on top of channel to complete OFET (organic field effect transistor) fabrication. [Copyright &y& Elsevier]

Measurement of velocity is essential for verification of the performance of many microelectromechanical system (MEMS) based fluidic devices. MEMS devices are usually made of silicon which is transparent at infrared wavelengths. Infrared thermal velocimetry has been developed to measure the velocity in silicon microchannels utilizing the infrared transparency of silicon. Applications are broad and include MEMS fluidic devices and bio-fluidic elements. Briefly, an infrared laser heats the flowing fluid in a silicon microchannel and the recording of the thermal image of the moving heated liquid permits determination of the average flow velocity. It has been demonstrated that this method can be used to measure a wide range of velocities (1 cm/s–1 m/s or higher) with an accuracy of ±10%. The velocity of the maximum radiative intensity point (V[sub MRIP]) along the center of the channel is chosen to characterize the velocity in the channel. Numerical results show good agreement with the experimental results. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

• ICEMA is oxidized on positive AC electrode to form stable electropolymerized layer. • PICEMAs formed by EP and RP methods mitigate diffusion-controlled self-discharge. • Isocyanate of PICEMA stabilizes ionic charged state to suppress self-discharge. • PICEMA formed by EP method shows minimized deterioration of capacitance and impedance. • EP method is suitable for highly capacitive and self-discharge-suppressed cell. To mitigate the self-discharge of supercapacitors (SCs), numerous researches have reported about the effective use of cell resistance, although this might provoke a deterioration of charge/discharge performances. In this work, isocyanate-based electrolytic additive, 2-isocyanatoethylmethacrylate (ICEMA), is polymerized by two methods, in-situ electropolymerization (EP) and radical-polymerization (RP), on activated carbon (AC) electrode to mitigate the diffusion-controlled self-discharge, which is a major contribution to the self-discharge herein. Although the radical-polymerized PICEMA reveals favorable suppression of self-discharge, only confined in bulk electrolyte and meso-region, this exhibits severe increases in all impedance parameters and deteriorated charge/discharge capabilities. The electropolymerized PICEMA, however, meets the bifunctional perspective, revealing aptly retained capacitance and suppressed self-discharge behavior throughout micro- and meso-regions. ICEMA is effectively electropolymerized on positive AC electrode at + 0.9 ~ 1.2 V (vs. AC), which is confirmed by the electrochemical impedance spectroscopy, electrochemical quartz microbalance, and X-ray photoelectron spectroscopy. The functionality of isocyanate group to suppress self-discharge is also confirmed by comparing methoxy group of ethylene glycol methyl ether methacrylate (EGMEMA). Image, graphical abstract [ABSTRACT FROM AUTHOR]

The New Madrid Seismic Zone, located in the central United States, produced five earthquakes in 1811–1812, 1843, and 1895, ranging from strong to major. A recurrence of its activity would cause substantial damage to the central U.S., but the magnitude of the most likely event is debatable. Accounting for 0.2 s spectral accelerations (SA) and peak ground velocities (PGV) with the local geologic conditions, this study offered methods for estimating the moment magnitudes (M) of these earthquakes. We analyzed 0.2 s SA and PGV and compared these data with the reported Modified Mercalli Intensities. Our estimates are M 7.6, 7.5, and 7.7 for the three 1811–1812 mainshocks in order of quake occurrence; M 6.2 for the 1843 Marked Tree, Arkansas; and M 6.7 for the 1895 Charleston, Missouri, earthquakes. These estimates are comparable to or exceed most previous approximations. Accordingly, potential liquefaction and resultant ground failure may affect most unconsolidated sediments throughout the central United States. • New Madrid Seismic Zone produced large earthquakes in 1811–1812, 1843, and 1895. • Site effects were evaluated to estimate the magnitudes. • Spectral accelerations and peak ground velocities were analyzed. • These values were then compared values with the MMIs. • Three earthquakes in 1811–1812 were likely > M 7.5. [ABSTRACT FROM AUTHOR]

For electrohydrodynamic jetting-on-demand, the conventional positive voltage pulse superposed by a dc bias voltage have been widely used. Once this voltage pulse was induced, the meniscus at the nozzle tip oscillated and its volume changed owing to the fluid supplied through the nozzle as well. To increase the maximum frequency for consistent jetting, it is desirable to minimize these phenomena. When the oscillation amplitude was sufficiently small to assume the occurrence of linear behavior and no jetting, the above phenomena could be well explained by using a harmonic oscillator model and a one-dimensional flow model. Based on this physical understanding, the root-polar voltage waveform was proposed and could significantly decrease the change in meniscus height; thus it was possible to increase the maximum frequency for consistent jetting. In addition, the residual oscillation could be also suppressed using an extra voltage pulse waveform. Furthermore, the root-polar voltage waveforms with a minus voltage pulse as well as a positive one could be demonstrated; thus it was shown that the root-polar voltage waveform could be implemented into ac-pulse modulated EHD jetting as well. [ABSTRACT FROM AUTHOR]

[Display omitted] • Efficient mixing required to maximize yield in supercritical water hydrolysis. • Numerically analyzed mixing in Y-junction mixer using LES with DPM. • Vertical orientation with upward supercritical inlet optimizes mixing. • Aligning natural and forced convection enhances mixing intensity. • Over 80% particles reach near mixing temperature in optimal configuration. In the continuous-type supercritical water hydrolysis process, rapid mixing of supercritical and subcritical streams is important to maximize yield and minimize degradation from over-reaction. This work investigated the particle behavior in a Y-junction mixer using large eddy simulation coupled with a discrete phase model, aiming to optimize the supercritical hydrolysis process for biomass conversion. A series of numerical simulations analyzed the influence of the mixer's orientation, flow directions, and flow rates on effective mixing and backflow prevention. The results demonstrated that the most effective mixing occurred in a vertically oriented Y-junction mixer with an upward-directed supercritical water inlet, aligning the momentum direction of natural and forced convection effectively. Consequently, over 80% of particles reached the temperatures close to the mixing temperature of supercritical and subcritical water within the Y-junction mixing zone, indicating enhanced mixing effectiveness and potential for efficient hydrolysis. This configuration also minimized backflow. [ABSTRACT FROM AUTHOR]

Abstract: In this work, the spreading and evaporation of 2–70pL droplet (17–50μm diameter) of water and ethylene glycol jetted by drop-on-demand piezo-driven jetting head on the heated substrate are studied. According to the experimental results, the interfacial oscillation phenomena of water droplet whose Ohnesorge number (Oh) is about 10−2 is similar to that in inviscid impact driven region, while that of ethylene glycol droplet (Oh ≈10−1) is similar to that in highly viscous impact driven region followed by capillary driven extra spreading. In addition, various time scales used for nano/micro-liter droplets agree well with the times for interfacial oscillation, viscous damping, extra wetting, and evaporation in pico-liter droplets. In the case of water droplet, the spreading processes end before the evaporation becomes significant. However, in the case of highly viscous ethylene glycol droplet, the extra wetting overlaps the evaporation at high temperature. [Copyright &y& Elsevier]

As acquiring bigger data becomes easier in experimental brain science, computational and statistical brain science must achieve similar advances to fully capitalize on these data. Tackling these problems will benefit from a more explicit and concerted effort to work together. Specifically, brain science can be further democratized by harnessing the power of community-driven tools, which both are built by and benefit from many different people with different backgrounds and expertise. This perspective can be applied across modalities and scales and enables collaborations across previously siloed communities. [ABSTRACT FROM AUTHOR]

Ablation of gold nanoparticle films on polymer was explored using a nanosecond pulsed laser, with the goal to achieve feature size reduction and functionality not amenable with inkjet printing. The ablation threshold fluence for the unsintered nanoparticle deposit was at least ten times lower than the reported threshold for the bulk film. This could be explained by the combined effects of melting temperature depression, lower conductive heat transfer loss, strong absorption of the incident laser beam, and the relatively weak bonding between nanoparticles. The ablation physics were verified by the nanoparticle sintering characterization, ablation threshold measurement, time resolved ablation plume shadowgraphs, analysis of ablation ejecta, and the measurement and calculation of optical properties. High resolution and clean feature fabrication with small energy and selective multilayer processing are demonstrated. [ABSTRACT FROM AUTHOR]

Currently, studies of flux switching machines are actively underway owing to several advantages of these machines, including their sturdy rotor structure and high output capability. This paper deals with an outer-rotor hybrid-excited flux-switching machine (FSM). The proposed machine embraces a homopolar structure and utilizes permanent magnets (PMs) for field excitation and a high-temperature superconducting (HTS) coil for flux regulation. The stator houses the HTS field coil, PMs, and armature windings. The outer rotor consists solely of an iron core. Thus, the machines are cost effective and can serve as a solution to the design and fabrication complexities of field current supplying and cooling systems. In this paper, the machine performance outcomes are analyzed using the 3D finite element method (FEM), and the validity of the proposed machine is verified. [ABSTRACT FROM AUTHOR]

Cognitive phenotypes characterize our memories, beliefs, skills, and preferences, and arise from our ancestral, developmental, and experiential histories. These histories are written into our brain structure through the building and modification of various brain circuits. Connectal coding, by way of analogy with neural coding, is the art, study, and practice of identifying the network structures that link cognitive phenomena to individual histories. We propose a formal statistical framework for connectal coding and demonstrate its utility in several applications spanning experimental modalities and phylogeny. [ABSTRACT FROM AUTHOR]

In this study, we present a theoretical model for an oscillating meniscus along with changing the volume of the sessile droplet on the electrohydrodynamic nozzle under various voltage waveforms, supported by experimental data. The transient volume change of the sessile droplet upon step electric pressure was modeled by a one-dimensional flow. The meniscus oscillation upon cyclic electric pressure was analyzed by a harmonic oscillator model. By combining these two models, the behavior of the sessile droplet, under a bi-directional square voltage pulse train with a different bias voltage, was analyzed. It is expected that this theoretical model can provide effective information in optimizing the voltage waveform for drop-on-demand electrohydrodynamic jetting. [ABSTRACT FROM AUTHOR]

Abstract: A 250-kW fuel cell reformer was numerically simulated with a user-defined function that was designed to simultaneously model reforming and combustion reactions. The calculation domain was a simplified 3-D configuration. To investigate the effects of geometry and operating conditions on the hydrogen productivity, the combustor outlet position, fuel ratio, equivalence ratio, and steam to carbon ratio were variable parameters. The numerical results show that the flow distributions in the furnace vary with respect to the combustor outlet position. The varied flow results in temperature distributions, which predicts the nonuniform hydrogen productivity in each reactor. Measuring the temperatures at reactor centers is an effective method for predicting the hydrogen productivity because the overall reforming reaction is affected by the average reactor temperature, which can be estimated by the temperature at the reactor center. The overall results for varying the operating conditions were summarized as a table by some nondimensional variables. By referring to the table, the proper operating conditions in similar reformer systems can be determined faster and more simply than by performing a conventional experiment. [Copyright &y& Elsevier]

Abstract: Electrohydrodynamic (EHD) printing is receiving much attention due to its high resolution printing capability, as well as its many advantages such as reduced manufacturing steps and non-toxic, flexible processes. However, many issues need be resolved before it can be widely used. In this work, to demonstrate EHD printing on demand, square pulse voltage signals are applied between a hole-type electrode and the nozzle supplied with working fluid from a reservoir at constant pressure. Continuous fine jet, pulsating fine jet, and pulsating droplet modes are observed depending on the voltage signal. To obtain the optimum voltage pulse duration, the change in the jetting start time is measured by varying the voltage configurations and hydrostatic pressure applied to the nozzle. Among the modes, the pulsating droplet mode is studied in detail for various voltage signals. Futhermore, the printing is demonstrated using the optimized voltage signal. [Copyright &y& Elsevier]

• Liquid jet from a plain orifice nozzle impinges on a vertical wall and splash occurs. • Depending on the gas Weber number of a jet, different breakup regimes can be seen. • Splash mainly depends on liquid Weber number of the drop resulting from jet breakup. • Splash increases with jet velocity until secondary breakup becomes dominant before impingement. • Splash increases as the impact distance increases. In this study, the splash phenomena of a plain orifice jet impinging on a vertical wall were examined. Experiments were carried out by changing the jet speed (i.e., inlet pressure) and the distance of a vertical wall with rounded and sharp-edged nozzles of different diameters, and the splashed fraction was measured by weighing the mass drained on the vertical wall. In addition, the breakup of the liquid jet and the flow patterns resulting from the jet impinging on the vertical wall were visualized. By increasing the velocity of a liquid jet emerging from a rounded nozzle, the Rayleigh, first wind-induced, and second wind-induced regimes could be observed in order. For the cavitating jet, the jet velocity became significantly larger than the volume flow rate divided by the nozzle area. Nevertheless, the trends of jet breakup as well as the splashed fraction results between the rounded and sharp-edged nozzles were similar for the same jet velocity. The splashed fraction reached its maximum value when small droplets resulted from the secondary breakup of large fragments started impinging on the vertical wall. In addition, the jet velocity at which the maximum splashed fraction attained decreased with increasing distance of the vertical wall from the nozzle exit. These experimental results were explained qualitatively in terms of the conditions of the liquid jet, breakup regime, drop impact, and splashing phenomena. [ABSTRACT FROM AUTHOR]

The authors have demonstrated organic thin film transistors (OTFTs) based on the ink-jet printed electrodes in which a reduced channel length is accomplished by laser ablation. Laser ablation on the dried silver nanoparticle electrode formed by ink-jet printing effectively shortened the channel length down to 5 μm, which is difficult to achieve by ink-jet printing alone. Reducing the channel length using this hybrid technique also allows them to observe the contact resistance effect in the OTFTs, which involves the printed silver nanoparticle electrode of a lower work function with respect to the ionization energy of the organic semiconductor. [ABSTRACT FROM AUTHOR]

Recently, the use of oxide-based nanomaterials for bio-imaging has received great attention owing to their remarkable stabilities as compared to those of conventional organic dyes. Therefore, the development of scalable methods for highly luminescent oxide materials with fine control of size has become crucial. In this study, we suggested modified flame spray pyrolysis (FSP) as a scalable method to produce a green-light emitting phosphor—Tb–doped Y2O3—in the nanometer size range. In our FSP method, an alkali salt (NaNO3) was found to be highly effective as a size-controlling agent when it is simply mixed with other metal nitrate precursors. The FSP of the mixture solution resulted in oxide composites of Y2O3:Tb3+ and NaxO. However, the sodium by-product was easily removed by washing with water. This salt-assisted FSP produced nano-sized and well-dispersed Y2O3:Tb3+ nanoparticles; their crystallinity and luminescence were higher than those of the bulk product made without the addition of the alkali salt. The nanoparticle surface was further coated with silica for biocompatibility and functionalized with amino groups for the attachment of biological molecules. [ABSTRACT FROM AUTHOR]

Herein, we report the effect of sonoluminescence and an initial dye concentration on the sonophotocatalysis of TiO2 for the degradation of eosin B, a textile dye. We first investigated the light illuminated during ultrasound irradiation (sonoluminescence) by photographic images, a radical indicator (luminol), and photoluminescence spectra of the detection range of 300–1050 nm. Next, we examined the synergistic effect of sonolysis on photocatalysis by comparing the dye degradation of sonophotocatalysis to that of individual contributions of sonolysis and photocatalysis. Since it was found that the synergist effect is highly engaged with a dye concentration and sonication power, we conducted the comparison test in different concentrations of eosin B (5 and 20 mg/L) and ultrasound powers (35.4, 106.1, and 176.8 W/cm2). When the concentration of dyes was low, negative synergistic effects were found at all ultrasound powers, whereas at the high concentration, positive synergistic effects were observed at high ultrasound power. This difference in synergistic effects was explained by the influence of ultrasound on dynamics of dye adsorption on the TiO2 surface. [ABSTRACT FROM AUTHOR]

This article presents a retraction of an earlier article that reported on the channel length by laser ablation.