827 research outputs found

    Toward a Theory of an IT Integration Infrastructure

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    Happiness Drives Performance

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    The article of record as published may be found at https://markets.businessinsider.com/news/stocks/happiness-drives-performance-103120049

    Far infrared giant dipole resonances in neutral quantum dots

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    A resonance behaviour of the far infrared absorption probability at a frequency \sim N^{1/4} is predicted for clusters of N electron-hole pairs (2\le N\le 110) confined in disk-shaped quantum dots. For radially symmetric dots, the absorption is dominated by a Giant Dipole Resonance, which accounts for more than 98 % of the energy-weighted photoabsorption sum rule.Comment: final versio

    Happy Soldiers are Highest Performers

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    17 USC 105 interim-entered record; under review.The article of record as published may be found at: https://doi.org/10.1007/s10902-021-00441-xWe examined the prediction of affective well-being to work performance in the United States Army. We found that high positive affect (PA), low negative affect (NA), and high optimism predicted awards for performance and heroism in a sample of 908,096 U.S. Army soldiers (mean age 29.60 years old, SD = 9.16 years; with over 1⁄4 of a million ethnic minor- ities and over 150,000 women). Baseline high PA, low NA, and high optimism predicted awards over a four-year follow up window, in which 114,443 soldiers (12.60%) received an award. Each well-being variable predicted future awards for both women and men, for enlisted soldiers as well as officers, for several ethnicities, for varying levels of education, and controlling for a number of other potential explanatory variables. The effects of high positive and low negative affect were additive, with each predicting significantly beyond the other. Comparing the soldiers highest vs. lowest in well-being predicted an almost four- fold greater award recognition in the high group. Awards were predicted by both high and low arousal positive emotions, as well as low sadness and low anger. The relations between PA, NA, and optimism with award attainment were curvilinear, with the greatest difference in award attainment occurring between low and moderate levels of affective well-being, with little effect between moderate and high well-being.Identified in text as U.S. Government work

    High capacity chipless RFID tags for biomass tracking application

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    The design of a low-cost, flexible, miniaturized and a high code density chipless RFID tag is presented as a solution for tracking the transportation of biomass fuel pellets. The performance of the tag is presented and demonstrates the applicability of the design for different material systems, whilst maintaining a compact size of 5.06cm 2. The tag consists of nested concentric hexagonal elements and a central spiral resonator suitable for ID encoding. The tag presented demonstrates code density of 3.6-bits/cm 2 , possesses angular stability up to 60º and high radar cross-section. The tag performance was also observed for tracking 5kg of fly ash biomass. Additionally, as the tag mass mostly consist of FR4, PET or Taconic TLX-0 with a minute mass of either copper, gold or silver, the tag can be easily combusted and disposed of during biomass combustion. The novel features of this tag are the combination of hexagonal and spiral shape slots for maximum space utilization thereby achieving high RCS signatures along with high code density. All these properties of the proposed chipless RFID tag provides a pioneering pathway for a real-time biomass tracking application. Keywords: Authors should not add keywords, as these will be chosen during the submission process (see http://journals.cambridge.org/data/relatedlink/MRF_topics.pdf for the full list

    Impact of dielectric substrates on chipless RFID tag performance

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    A five-slot hexagonal shape chipless RFID tag is designed, simulated, and manufactured on FR4 substrate. The designed tag's copper geometry was replicated on a wide range of dielectric substrate to quantify the impact on resonance quality factor (RQF) and resonating frequencies. The tag's performance was assessed in three configurations. First, a hexagonal shape tag's radar cross section (RCS) was studied over different dielectric substrates. The various dielectric substrate effects were investigated over the maximum read range, resonant frequencies and RQF. In the second evaluation, the physical geometry of the tag was adjusted to achieve the spectral signatures in 2–7 GHz frequency band with high RQF. In step three, the optimized tag geometry was manufactured on FR4, Roger Duroid 5880, and polyethylene naphthalate (PEN) substrates. Denford milling machine for PCB engraving and inkjet printing for silver nanoparticles deposition were used for tags manufacturing. During tag manufacturing, copper and silver were used as conducting materials for RCS backscattering. The tag RCS response was measured by vector network analyzer with bi-static antenna setup. The analysis of different dielectric substrate provides a pathway of designing a novel substrate by using various nanomaterials

    The Impossibility of a Perfectly Competitive Labor Market

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    Using the institutional theory of transaction cost, I demonstrate that the assumptions of the competitive labor market model are internally contradictory and lead to the conclusion that on purely theoretical grounds a perfectly competitive labor market is a logical impossibility. By extension, the familiar diagram of wage determination by supply and demand is also a logical impossibility and the neoclassical labor demand curve is not a well-defined construct. The reason is that the perfectly competitive market model presumes zero transaction cost and with zero transaction cost all labor is hired as independent contractors, implying multi-person firms, the employment relationship, and labor market disappear. With positive transaction cost, on the other hand, employment contracts are incomplete and the labor supply curve to the firm is upward sloping, again causing the labor demand curve to be ill-defined. As a result, theory suggests that wage rates are always and everywhere an amalgam of an administered and bargained price. Working Paper 06-0

    The kinetics studies and thermal characterisation of biomass

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    This work aims to investigate and develop a method to evaluate and predict the combustion behaviour and combustion efficiency of different biomass commonly used in power plants via simple characterisation methods. 11 types of agricultural and industrial wastes were characterised using thermogravimetric analyser to obtain the derivative thermogravimetric (DTG) data and kinetic parameters. For the samples tested, the initiation temperatures were found to be in the range between 224.39 0 C and 260.33 0 C, whilst the local minimum temperatures between 2 peaks were within the range of 360.36 to 382.74 0 C. It was established that there is a clear, direct relationship between the pre-exponential factor and the temperature interval for the first step of combustion. This trend was apparent and recorded for the 2 heating rates tested. © 2019 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Peer-review under responsibility of the scientific committee of ICAE2018 - The 10th International Conference on Applied Energy

    Critical change in the Fermi surface of iron arsenic superconductors at the onset of superconductivity

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    The phase diagram of a correlated material is the result of a complex interplay between several degrees of freedom, providing a map of the material's behavior. One can understand (and ultimately control) the material's ground state by associating features and regions of the phase diagram, with specific physical events or underlying quantum mechanical properties. The phase diagram of the newly discovered iron arsenic high temperature superconductors is particularly rich and interesting. In the AE(Fe1-xTx)2As2 class (AE being Ca, Sr, Ba, T being transition metals), the simultaneous structural/magnetic phase transition that occurs at elevated temperature in the undoped material, splits and is suppressed by carrier doping, the suppression being complete around optimal doping. A dome of superconductivity exists with apparent equal ease in the orthorhombic / antiferromagnetic (AFM) state as well as in the tetragonal state with no long range magnetic order. The question then is what determines the critical doping at which superconductivity emerges, if the AFM order is fully suppressed only at higher doping values. Here we report evidence from angle resolved photoemission spectroscopy (ARPES) that critical changes in the Fermi surface (FS) occur at the doping level that marks the onset of superconductivity. The presence of the AFM order leads to a reconstruction of the electronic structure, most significantly the appearance of the small hole pockets at the Fermi level. These hole pockets vanish, i. e. undergo a Lifshitz transition, at the onset of superconductivity. Superconductivity and magnetism are competing states in the iron arsenic superconductors. In the presence of the hole pockets superconductivity is fully suppressed, while in their absence the two states can coexist.Comment: Updated version accepted in Nature Physic
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