22,643 research outputs found

    CE Challenges: Work to Do

    No full text
    CE has been used for more than two decades now. Despite many successes and advantages, there are still many challenges to be addressed. These challenges are both technical and organisational. In the paper we will address the current challenges of CE. Many challenges are related to the exchange of data and knowledge and to the systems that make data and knowledge exchange possible. Although much progress has been made in enabling extensive data and knowledge exchange and use, much remains to be wished. For example, there are still barriers to data exchange. Technically, these barriers may consist of different formats, differences in infrastructures and systems, and different semantics. There are also organisational and political barriers. For example, investment in information system may heavily impact upstream suppliers, while revenues of better information exchange may predominantly be gained by downstream actors. Without sharing costs and revenues, chain-wide information exchange will not be easily realised. Another barrier is the possible lack of willingness to share information, because of potential misuse of knowledge and loss of power. The paper is organised as follows. First we will describe the current manifestation of CE as described in a recent book. Second, we will list current trends in CE. Third, we will present some Critical Success Factors (CSFs) that are considered relevant for implementing and adapting CE practices. Last, we indicate some research and practical questions to be addressed, especially for areas that have a high potential and actual impact. </p

    Response to Erickson-Gini’s "Problems and solutions in dating Nabataean pottery in the post-annexation period"

    No full text
    In the late 1990s, Stephan G. Schmid published a chronological typology of Nabataean Painted Fineware (NPFW) that was widely accepted by scholars of Nabataea and Roman Arabia. Tali Erickson-Gini has since raised concerns about parts of his NPFW typology, specifically related to two decoration types dating to the end of the 1st century and the beginning of the 2nd century CE (Dekorphases 3b and 3c). This article is a response to Erickson-Gini’s critique, published in this volume. We find that there is sufficient evidence to broadly validate Schmid’s proposed dating for the beginning of production of Dekorphases 3b and 3c to the late 1st century and early 2nd century CE, respectively

    Research programmes and the student science learning literature

    No full text
    Le but de cet article est de présenter une vision personnelle de l'évolution des cadres conceptuels qui se sont produits dans le champ des recherches sur la compréhension des élèves en sciences durant ces vingt dernières années et de spéculer sur leur évolution future. Le but de clarifier ces évolutions est d'autant plus important que ce champ montre une « diversité considérable des approches qui ont conduit à une prolifération des termes, des méthodes de recherche et des approches théoriques pour décrire les «engagements cognitifs » des élèves (Driver & Erickson, 1983, p. 39). De fait, cette diversité a encore augmenté

    Synthesis optimization and charge carrier transfer mechanism in LiLuSiO<sub>4</sub>:Ce, Tm storage phosphor

    No full text
    LiLuSiO4:Ce and LiLuSiO4:Ce, Tm show very efficient charge carrier storage properties upon beta irradiation after samples have received treatment in vacuum. They outperform the commercial storage phosphor BaFBr(I):Eu2+ in many aspects. The influence of the synthesis conditions, Ce and Tm concentration, nonstoichiometry and codoping with Ca, Hf, Al and Ge are reported. Based on the results of the synthesis optimization, thermoluminescence (TL) emission and TL excitation spectra a mechanism of charge carrier transfer, storage, and recombination during irradiation and thermal or optical readout is proposed.Accepted Author ManuscriptRST/Fundamental Aspects of Materials and EnergyRST/Luminescence Material

    The impact of P(NDI2OD-T2) crystalline domains on the open-circuit voltage of bilayer all-polymer solar cells with an inverted configuration

    No full text
    We fabricated P(NDI2OD-T2)/PTB7 bilayer all-polymer solar cells with an inverted configuration, where the annealing temperature was systematically varied. The current density-voltage behavior was investigated and the structural properties of the P(NDI2OD-T2) layers were characterized. Absorption spectroscopy, surface morphology, and crystallite analysis showed that increasing phase segregation of P(NDI2OD-T2) films occurred as the annealing temperature increased. We found that, as the P(NDI2OD-T2) stacking improved, with larger domains, the open-circuit voltage decreased and the saturation dark current density increased. This work provides a guide for the processing of P(NDI2OD-T2) layers to maximize the power conversion efficiency of all-polymer solar cells. (C) 2015 Author(s).open1186sciescopu

    Data and code for: Variational Graph Author Topic Modeling

    No full text
    This is the tensorflow implementation of KDD-2022 paper "Variational Graph Author Topic Modeling" by Delvin Ce Zhang and Hady W. Lauw. VGATM is a Graph Neural Network model that extracts interpretable topics for documents with authors and venues. Topics of documents then fulfill document classification, citation prediction, etc. </p

    Updated analytical solutions of continuity equation for electron beams precipitation – I. Pure collisional and pure ohmic energy losses

    No full text
    We present updated analytical solutions of continuity equations for power-law beam electrons precipitating in (a) purely collisional losses and (b) purely ohmic losses. The solutions of continuity equation (CE) normalized on electron density presented in Dobranskis & Zharkova are found by method of characteristics eliminating a mistake in the density characteristic pointed out by Emslie et al. The corrected electron beam differential densities (DD) for collisions are shown to have energy spectra with the index of −(γ + 1)/2, coinciding with the one derived from the inverse problem solution by Brown, while being lower by 1/2 than the index of −γ/2 obtained from CE for electron flux. This leads to a decrease of the index of mean electron spectra from −(γ − 2.5) (CE for flux) to −(γ − 2.0) (CE for electron density). The similar method is applied to CE for electrons precipitating in electric field induced by the beam itself. For the first time, the electron energy spectra are calculated for both constant and variable electric fields by using CE for electron density. We derive electron DD for precipitating electrons (moving towards the photosphere, μ = +1) and ‘returning’ electrons (moving towards the corona, μ = −1). The indices of DD energy spectra are reduced from −γ − 1 (CE for flux) to −γ (CE for electron density). While the index of mean electron spectra is increased by 0.5, from −γ + 0.5 (CE for flux) to −γ + 1(CE for electron density). Hard X-ray intensities are also calculated for relativistic cross-section for the updated differential spectra revealing closer resemblance to numerical Fokker–Planck (FP) solutions

    Introduction and Author Biographical Notes

    No full text
    The Introductory Notes include The Cutting EDge\u27s mission statement, editorial board, founder\u27s note, and author\u27s biographies
    corecore