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In this work, we describe a new reversible photoalignment effect for the director in nematic liquid crystals that provides an approach for the creation of lenses whose optical power can be recorded and erased. The possibility of creating a rewritable lens has very important practical implications, for example, in the ophthalmic lens industry. A rewritable ophthalmic lens could be a convenient solution for patients whose compensation needs change over time due to age-related physiological changes, such as the onset and progression of presbyopia. Using rewritable lenses, small lens power corrections could be implemented through a rewriting procedure on the mounted lens without resurfacing or manufacturing and mounting a new lens. More generally, this new effect multiple potential applications in the creation of rewritable optical systems, such as reconfigurable optical networks, index-tunable antireflective coatings and optically rewritable phase gratings. [ABSTRACT FROM AUTHOR]

Early estimation of the peak power consumption of a system under development is crucial in assessing the design’s thermal profile and reliability, and in benchmarking the chip-level power management features. In this paper, we present a high-level systematic methodology for generating the appropriate traffic patterns that trigger the peak power consumption in a network-on-chip (NoC), irrespective of the latter’s structural and functional properties. The generation of peak-power traffic is performed by solving a novel optimization problem based on integer linear programming, which models the traffic that can realistically flow in the network, thus avoiding any fake and pessimistic scenarios. This formulation can handle arbitrary network configurations and routing algorithms, including heterogeneous network topologies with multiple link widths and voltage/clock domains. The proposed technique maximizes both the network utilization and the data switching activity, thereby causing, on average, ${4 \times }$ higher power consumption than synthetic traffic patterns with random behavior. Most importantly, the proposed method reveals the realistic ceiling of the NoC’s peak power consumption, by reporting significantly lower peak power (${3\times }$ less), as compared to fake worst-case scenarios that can never, in fact, occur during the NoC’s normal operation. [ABSTRACT FROM AUTHOR]

We demonstrated a high brightness narrow-linewidth microsecond (μs) pulse green laser from second harmonic generation (SHG) of a master oscillator power amplifier (MOPA) laser system. The oscillator was a quasi-continuous wave pulsed diode-side-pumped 1064 nm Nd:YAG laser with an average output power of 45.2 W and a beam quality factor of M 2  = 1.21, operating at a pulse repetition frequency of 500 Hz with a ∼160 μs of pulse duration. After a two-stage amplifier, the fundamental output power of MOPA system was increased up to 198 W. Using a type-I lithium triborate nonlinear crystal, the maximum SHG output power of 78.4 W at 532 nm was obtained with a linewidth of 0.54 pm and a beam quality factor M 2 less than 1.61. The brightness of the green light was as high as 1.08 × 10 10  W/cm 2  sr. This is, to the best of our knowledge, the highest brightness solid state light source for the narrow-linewidth μs pulse green lasers at 532 nm. [ABSTRACT FROM AUTHOR]

This note aims to generalize the reverse weighted arithmetic-geometric mean inequality of n positive invertible operators due to Lawson and Lim. In addition, we make comparisons between the weighted Karcher mean and Lawson-Lim geometric mean for higher powers. [ABSTRACT FROM AUTHOR]

This study presents a new hybrid scheme that effectively reduces the peak-to-average power ratio (PAPR) of discrete cosine transform based single-carrier frequency division multiple access (DCT-SCFDMA) signal as well as improves the bit error rate (BER) performance of system. The method is to consolidate pulse shaping process with a novel hyperbolic tangent companding technique so that the PAPR of the SCFDMA signals can be further reduced by enabling the transformation of the amplitude of modulated signals into uniform distribution. Through extensive computer simulations, it has been shown that proposed scheme achieves significant improvements in BER and PAPR reduction over the existing standard pulse shaping methods when used alone in DCT-SCFDMA system as far as the lowest PAPR is concerned without degrading the error performance of the system. [ABSTRACT FROM AUTHOR]

A novel design of a miniature search coil magnetometer is proposed based on the integration of the electronics and batteries within the hollow core of the search coil. In contrast with conventional designs, where the search coil and its electronics have individual housings and electrostatic shields, this paper presents a design in which the core of the search coil serves both as the housing and the magnetic shield for the electronics and batteries. Moreover, the electrostatic shield of the search coil also shields the electronics and batteries. We found that a thin-wall tube core with sufficient permeability is able to replace a solid rod core without decreasing the average flux sensed by the coil winding. In addition, the outer diameter of the tube core can be increased beyond its optimum size to provide more space for the electronics and batteries without considerably affecting the search coil resolution. To validate the effectiveness of this new design, a miniature search coil magnetometer was built and tested for very low frequencies and ultra-low power consumption. [ABSTRACT FROM AUTHOR]

Extending the result of Bor(2016) and subsequently Majhi et al, a new result concerning absolute indexed Riesz Summability factors, using quasi power increasing sequence, has been established. [ABSTRACT FROM AUTHOR]

A simplified model consisting of a laser diode, air gap, and optical fiber is used to calculate power and spectral characteristics and the band width of the radiation of laser with fiber Bragg grating. The results of the simplified model are in reasonable agreement with the experimental data on power and spectral characteristics. The radiation band width of the laser diode with fiber Bragg grating can be less than the band width for a single laser diode by four orders of magnitude. [ABSTRACT FROM AUTHOR]

We study the effect of dimension 7 and 8 operators on inclusive semileptonic B decays and the extraction of | V c b | . Using moments of semileptonic B decay spectra and information based on the Lowest-Lying State saturation Approximation (LLSA) we perform a global fit of the non-perturbative parameters of the heavy quark expansion including for the first time the O ( 1 / m b 4 , 5 ) contributions. Higher power corrections appear to have a very small effect on the extraction of | V c b | , independently of the weight we attribute to the LLSA. [ABSTRACT FROM AUTHOR]

Three interface joint models for calculating energy release rate are extended to include hygrothermal effect with consideration of uniform or nonuniform changes of temperature or moisture through layer thickness in a cracked bilayer beam system using both J-integral and correction methods. The method of J-integral leads to a general expression of total energy release rate in terms of the crack-tip moments and forces, while the correction method gives explicit formulas of total energy release rate with inclusion of a separate energy release rate term subjected to only mechanical loads. Several bilayer beam fracture specimens subjected to transverse load or equivalent bending moment and thermal load are considered to validate accuracy of two methods in connection with three interface joint models, and the results show that the flexible joint model produces the best predictions for all the specimens. A parameter study is conducted to evaluate influences of thickness ratio, modulus ratio of upper and lower layers, change of temperature, and temperature gradient on the energy release rate. All the factors show a pronounced influence on the energy release rate, and a special attention is paid to evaluate effect of temperature change and temperature gradient on the energy release rate of bilayer beams. The moisture change and its gradient have the same effect and formulations on the energy release rate of bilayer beams as those of temperature, and the moisture portion of derivations and its effect are thus not given in detail. [ABSTRACT FROM AUTHOR]

The article offers information on the back-of-the-envelope method, also called balancing. It mentions that balancing is applied to calculate the Earth's approximate orbital speed v, when mass is m. It states that balancing requires two legs: lumping, as twiddle approximations, and dimensional analysis. It further states that balancing often works because it is an abbreviated form of dimensional analysis and inherits part of dimensional analysis's power.

Quadrupole mass filters using non-sinusoidal driving potentials present exciting opportunities for new functionality. Predicting figures of merit like resolving power and transmission efficiency helps characterize these emerging devices. To this end, matrix methods of solving the Hill equation of ion motion are employed to calculate stability diagrams and pseudopotential well depth maps in the a,q plane for arbitrary waveforms. The theoretical resolving power and well depth of digital, trapezoidal and sinusoidal mass filters are compared. Simplified expressions for digital mass filter operation are presented. [ABSTRACT FROM AUTHOR]

Effective field theories are the most general tool for the description of low energy phenomena. They are universal and systematic: they can be formulated for any low energy systems we can think of and offer a clear guide on how to calculate predictions with reliable error estimates, a feature that is called power counting. These properties can be easily understood in Wilsonian renormalization, in which effective field theories are the low energy renormalization group evolution of a more fundamental - perhaps unknown or unsolvable - high energy theory. In nuclear physics they provide the possibility of a theoretically sound derivation of nuclear forces without having to solve quantum chromodynamics explicitly. However there is the problem of how to organize calculations within nuclear effective field theory: the traditional knowledge about power counting is perturbative but nuclear physics is not. Yet power counting can be derived in Wilsonian renormalization and there is already a fairly good understanding of how to apply these ideas to non-perturbative phenomena and in particular to nuclear physics. Here we review a few of these ideas, explain power counting in two-nucleon scattering and reactions with external probes and hint at how to extend the present analysis beyond the two-body problem. [ABSTRACT FROM AUTHOR]

The present note summarizes the discourse on power counting issues of chiral nuclear forces, with an emphasis on renormalization-group invariance. Given its introductory nature, I will lean toward narrating a coherent point of view on the concepts, rather than covering comprehensively the development of chiral nuclear forces in different approaches. [ABSTRACT FROM AUTHOR]

Alternative Binary Offset Carrier (AltBOC) modulation signal has the constraint of an equal power allocation scheme. Thus, it is not flexible enough to meet different requirements. To solve this problem, we propose a General AltBOC (GAltBOC) modulation. The proposed technique can achieve the same function as AltBOC. Meanwhile, its power allocation ratio can be adjusted when required. The detailed derivation of the GAltBOC modulation is presented, and three representative cases as well as the signal properties are discussed. To further improve the combination efficiency, we develop the Interlacing GAltBOC (IGAltBOC) modulation based on the GAltBOC modulation. The Power Spectrum Density (PSD) and correlation functions of the proposed signals are verified by simulation. The code tracking error and implementation complexities are analysed and compared with existing methods. Results show the proposed signals indeed enhance the flexibility of power allocation ratio with the same level code tracking accuracy. Compared with AltBOC modulation, the proposed signal can reach a higher combination efficiency at the expense of relatively higher implementation complexity. Compared with Asymmetric Constant Envelope Double-sideband (ACED) modulation, the proposed signals have significantly lower complexity of signal generation, which is helpful in simplifying the signal generation in the payload transmitter. [ABSTRACT FROM AUTHOR]

Although the Diels-Alder reaction has long been utilized for the preparation of numerous heterocycles, opportunities to extend its power remain. Herein, we detail a simple, modular, and robust approach that combines various amines regioselectively with 4,6-dichloropyrone to create substrates which, under appropriate conditions, can directly deliver varied indolines and hydroindolines through [4+2] cycloadditions with substitution patterns difficult to access otherwise. As an initial demonstration of the power of the strategy, several different natural products have been obtained either formally or by direct total synthesis, with efforts toward one of these-the complex amaryllidaceae alkaloid gracilamine-affording the shortest route to date in terms of linear step count. [ABSTRACT FROM AUTHOR]

We report a high peak power ytterbium-doped fiber laser that emitted linearly-polarized laser at 1064 nm. An intracavity polarization-maintaining (PM) acousto-optic modulator (AOM) was used as a Q-switch to generate pulsed laser output. The whole system was constructed with all-fiber structure. The power of the polarized laser reached 4.21 W and a polarization purity of greater than 97.6% under the repetition rate of 20 kHz. The pulse width was 37 ns, which implied a 5 kW peak power and 0.2 mJ pulse energy. It is the highest peak power output from a linearly-polarized, Q-switched fiber laser oscillator to the best of our knowledge. [ABSTRACT FROM AUTHOR]

Organolead iodide perovskite showing tubular morphology was fabricated on mesoporous TiO2 film via a one-step spin-coating procedure. These perovskite tubes with the external diameter of 1 μm were found to facilitate the charge separation at perovskite/hole-transport material (HTM) interfaces. This engenders a tubular perovskite device showing a higher fill factor over the device with planar perovskite, and improves power conversion efficiency accordingly. [ABSTRACT FROM AUTHOR]

Power Management Strategies (PMSs) to control stand-alone energy systems affect the reliability of meeting load demand as well as the cyclic operation of various subsystems. The hybridisation of sources through the integration of hydrogen fuel cells with energy storage means optimising the PMS should be “intelligently” done unless relying on rule-based PMSs which are simplistic to use but subject to lack of optimisation. This paper presents the methodology and validation of a lab-scale (desktop) energy system controlled by a predictive PMS. Validation of the intelligently based PMS can be done in the lab-scale before (costly) full deployment in the field, but experiments to support this have not been reported in relation to hydrogen systems. The experimentally tested hybrid energy system consists of an emulated renewable power source which can represent solar-PV and/or wind generators, battery bank and PEM fuel cell integrated with metal hydride storage. Experimental testing as well as the use of real-time predictions using Neural Networks is utilised. The effects of several control parameters which are either hardware dependant or affect the predictive algorithm are investigated with system performance, under the predictive PMS, benchmarked against a rule-based PMS. The results reveal that a predictive PMS is impacted by the prediction horizon used to forecast the availability of renewables or load, the decision time interval used for updating the PMS as well as time lags resulting from hardware sensors used to convey system status to the decision algorithm responsible for updating the PMS. The maximum thresholds of the above mentioned control parameters are 120, 15 and 3 s, respectively. Beyond these limits, the ability of the predictive PMS to effectively control the system degrades significantly. This study demonstrates the feasibility of using real-time predictions of renewable resources and load demand to optimise a PMS in a stand-alone energy system and experimentally validates this, which has not been previously reported. [ABSTRACT FROM AUTHOR]

It is proposed to obtain a full physical description of total solar cycle forcing from the weighted average absolute total solar irradiance (TSI) for the entire 11-year cycle. This approach enables quantitative determination of absolute cycle forcing and helps predict its impact on processes in the Sun-Earth system. A similar approach is used to determine relative solar activity cycle forcing. The relative radiative forcing of cycles 1-24 is calculated and studied together with their lengths to find an inverse relationship between the cycle length and radiative forcing: the smaller the forcing (TSI and solar activity), the larger the length, and vice versa. The inverse relationship between solar cycle length and radiative forcing is attributed to the influence of the quasi-bicentennial solar cycle. The results may explain why the length of 11-year solar cycles can serve as a possible indicator of climate change only during the growth or decline phase of the quasi-bicentennial solar cycle. [ABSTRACT FROM AUTHOR]

This paper proposes a neural network based power flow analysis method that applied on a grid connected and ring-shaped micro grid. As the use of micro grids increasing rapidly, it becomes necessary to analyze them for different operating and loading conditions as large power systems. At the outset, a MG is designed and simulated under MATLAB / Simulink platform. Normal operation data collected and stored. Then, different loading scenarios performed, operational data collected and stored to use for proposed method. Intelligent systems are used to process these data and also for training. After training a fully different scenario is created and the effectiveness of the proposed method is verified through simulation study. [ABSTRACT FROM AUTHOR]

The nonlinear polarization dependence (NPD) of a fiber polarization diversity system (PDS) is studied by means of the nonlinear power transfer functions (PTFs) of two orthogonally polarized beam paths (PBPs). In principle, a polarization-independent PDS can be developed when the PTF curves are centrally symmetric to each other in a certain range of input power. As an example, a data-pump four-wave-mixing-based PDS is investigated by simulation and experiment, and the probe and pump powers are optimized for the minimal NPD. Experimental results show that, by adding a power-saturated erbium-doped fiber amplifier to the PDS, the dynamic range of input power can be increased up to 26 dB, along with 4 dB extinction ratio (ER) improvement. [ABSTRACT FROM AUTHOR]

The article presents the discussion on Joint European Torus (JET) showing a campaign for generating substantial amounts of fusion power by using powerful magnets for constraining a hot plasma.

Pulsing is prevalent in nature. As resource pulse has been recognized as one of the major factors influencing ecosystem structures and processes, it is important to investigate why nature pulses and what benefits an ecosystem obtains from pulsed resources. The main question of this study was that if a system could be exposed to either constant external resources or pulsed external resources of the same temporal average intensity, which resources would maximize power acquisition of a system. To answer the question, this study tested how matching of pulsed resources affects total empower acquisition of a system using numerical simulation models and a refined dynamic emergy accounting method. A producer–consumer model system was built and simulated by varying phases and frequencies of pulsed energy sources. It was hypothesized that matching of frequency and phase among two or more pulsed energy sources increases the empower acquisition of a system, compared with a system under constant energy sources. The simulation results showed that in systems of two energy sources, matching phases and frequencies of the pulsed energy sources involved in primary production is critical to increase total empower acquisition and consumer energy storage. The primary mechanism was that the matching of pulsed resources in phase and frequency promotes energy acquisition of primary producers that is further efficiently transferred for the production of consumers. Energy acquisition of consumers was strongly correlated with total empower acquisition of the system presumably because the consumers are in the high energy hierarchical position controlling the producers thus contributing to the total empower acquisition through the system. [Copyright &y& Elsevier]

Some apparently confusing aspects of Newton’s laws as applied to an aircraft in normal horizontal flight are neatly resolved by a careful analysis of force, momentum, energy and power. A number of related phenomena are explained at the same time, including the lift and induced drag coefficients, used empirically in the aviation industry. [ABSTRACT FROM AUTHOR]

In this study, magnetic and power absorption properties of a series of iron oxide nanoparticles with average sizes 〈 d〉 ranging from 3 to 23 nm were reported. The nanoparticles were prepared by thermal decomposition of Iron(III) acetylacetonate in organic media. From the careful characterization of the magnetic and physicochemical properties of these samples, the specific power absorption (SPA) values experimentally found were numerically reproduced, as well as their dependence with particle size, using a simple model of Brownian and Néel relaxation at room temperature. SPA experiments in ac magnetic fields ( H = 13 kA/m and f = 250 kHz) indicated that the magnetic and rheological properties played a crucial role determining the heating efficiency at different conditions. A maximum SPA value of 344 W/g was obtained for a sample containing nanoparticles with 〈 d〉 = 12 nm and dispersion σ = 0.25. The observed SPA dependence with particle diameter and their magnetic parameters indicated that, for the size range and experimental conditions of f and H studied in this study, both Néel and Brown relaxation mechanisms are important to the heat generation observed. [ABSTRACT FROM AUTHOR]

Relationships determining the dependence of sum-frequency CW generation (SFG) power in a SRS-laser on the pumping, active media, and resonators at the fundamental, Stokes, and SFG frequencies were obtained and analyzed for a wide range of their values. It was shown that even weak reflection of the generated radiation by the output mirror could significantly influence the generation power. [ABSTRACT FROM AUTHOR]

To calculate the power of conventional or chemical explosives, several methods and formulae available in both the regulations in place and specialized bibliography were analyzed. Given the limitations of the available procedures that do not provide uniform evaluation criteria and that are markedly based on empiricism to deal with the topic appropriately, new formulae were deduced for the calculation of this key parameter taking as a key element the expression for calculating the power generated by elongated cylindrical charges; which are the most widely used in explosions and the methods to express them are then proposed. The formulae are deduced as a theoretical application to calculate the explosive strength and the detonation pressure of this type of charges. [ABSTRACT FROM AUTHOR]

The article presents a study which discusses the strength and power characteristics of elite English rugby league players. The study measures the agility, vertical jump, isometric squat and knee flexion of English Superleague club players. The study revealed that Forward players demonstrated greater body mass, height, and power in the 40-kilogram (kg) jump squat.

The article presents a lesson plan for primary education which teaches concepts about energy and power by using STEM activities.

The article offers the author's comment on the article "Testing bioequivalence for multiple formulations with power and sample size calculations" by C. Zheng, J. Wang and L. Zhao. He states that the authors proposed error-rate control in the multiplicity-adjusted TOST (MATOST) two one-sided tests procedure is incorrect. He also discusses a simple Holm-based procedure with correct error-rate control.

Changes in solvent-solute induced polarities caused by variations in solvent density affect excess enthalpies of a solution. When the solution serves as the working fluid for a transcritical power cycle, changes in solvent-solute bonding energies between the solvent in its dense liquid and less dense supercritical fluid state can favorably impact the cycle's energy conversion potential. Energy transfers internal to the cycle caused by changes in induced polarities challenge Carnot's and Clausius's original assumptions that heat energy is the lowest form of energy to which all other forms degrade. [ABSTRACT FROM AUTHOR]

The self-stimulated Raman laser operation of a Nd:Lu0.99La0.01 VO4 new crystal is presented. A 0.3at.% Nd doped Lu0.99La0.01 VO4 crystal in dimensions 3 × 3 × 20 mm3 is adopted as the self-stimulated Raman crystal. At a pulse repetition frequency of 14 kHz, average output powers of 240 mW for the first Stokes light at 1181 nm and 660 mW for the fundamental light at 1068 nm are obtained under an incident pump power of 5.5 W. The pulse widths of the first Stokes light and fundamental light are about 15 and 25 ns. The slope efficiencies are about 12.7% and 18.8% with respect to the incident pump power. [ABSTRACT FROM AUTHOR]

The power formula for turbulent velocity profiles in a circular tube offered by G I Barenblatt, A J Chorin, and V M Prostokishin in their paper “Turbulent flows at very large Reynolds numbers: new lessons learned” (Phys. Usp.57 250 (2014); Usp. Fiz. Nauk184 265 (2014)) is discussed. [ABSTRACT FROM AUTHOR]