Scientometric engineering: Exploring citation dynamics via arXiv eprints

Scholarly communications have been rapidly integrated into digitised and networked open ecosystems, where preprint servers have played a pivotal role in accelerating the knowledge transfer processes. However, quantitative evidence is scarce regarding how this paradigm shift beyond the traditional journal publication system has affected the dynamics of collective attention on science. To address this issue, we investigate the citation data of more than 1.5 million eprints on arXiv (https://arxiv.org) and analyse the long-term citation trend for each discipline involved. We find that the typical growth and obsolescence patterns vary across disciplines, reflecting different publication and communication practices. The results provide unique evidence on the attention dynamics shaped by the research community today, including the dramatic growth and fast obsolescence of Computer Science eprints, which has not been captured in previous studies relying on the citation data of journal papers. Subsequently, we develop a quantitatively-and-temporally normalised citation index with an approximately normal distribution, which is useful for comparing citational attention across disciplines and time periods. Further, we derive a stochastic model consistent with the observed quantitative and temporal characteristics of citation growth and obsolescence. The findings and the developed framework open a new avenue for understanding the nature of citation dynamics. Peer Review https://publons.com/publon/10.1162/qss_a_00174

Importance of radiative transfer processes in urban climate models: a study based on the PALM 6.0 model system

Including radiative transfer processes within the urban canopy layer into microscale urban climate models (UCMs) is essential to obtain realistic model results. These processes include the interaction of buildings and vegetation with shortwave and longwave radiation, thermal emission, and radiation reflections. They contribute differently to the radiation budget of urban surfaces. Each process requires different computational resources and physical data for the urban elements. This study investigates how much detail modellers should include to parameterize radiative transfer in microscale building-resolving UCMs. To that end, we introduce a stepwise parameterization method to the Parallelized Large-eddy Simulation Model (PALM) system 6.0 to quantify individually the effects of the main radiative transfer processes on the radiation budget and on the flow field. We quantify numerical simulations of both simple and realistic urban configurations to identify the major and the minor effects of radiative transfer processes on the radiation budget. The study shows that processes such as surface and vegetation interaction with shortwave and longwave radiation will have major effects, while a process such as multiple reflections will have minor effects. The study also shows that radiative transfer processes within the canopy layer implicitly affect the incoming radiation since the radiative transfer model is coupled to the radiation model. The flow field changes considerably in response to the radiative transfer processes included in the model. The study identified those processes which are essentially needed to assure acceptable quality of the flow field. These processes are receiving radiation from atmosphere based on the sky-view factors, interaction of urban vegetation with radiation, radiative transfer among urban surfaces, and considering at least single reflection of radiation. Omitting any of these processes may lead to high uncertainties in the model results.

Sensitivity Study on the Parameters of a Hygrothermal Transfer Model of Air, Heat and Mass Transfer

The energy performance of buildings represents a major challenge in terms of sustainable development. The buildings and buildings construction sectors combined are responsible for over one-third of global final energy consumption and nearly 40% of total direct and indirect CO2 emissions. In order to reduce the energy consumption of buildings and their harmful impact on the environment, special attention has been paid in recent years to the use of bio-based materials. Several works have been carried out in the last decades in order to model the coupled heat, air and moisture transfers in the building envelope but the difficulties lies in the identification of numerous parameters that the HAM proposed models use. In the present paper, a sensitivity study regarding the HAM parameters is implemented in order to apprehend the most determining parameters during the transfer processes. A reduced model based on these parameters is then determined.

Engineering metal oxide semiconductor nanostructures for enhanced charge transfer: fundamentals and emerging SERS applications

Fundamentals of doping engineering strategies of metal oxide semiconductors and various charge transfer processes for emerging SERS applications are discussed.

Процессы передачи энергии в эвлитите Sr-=SUB=-3-=/SUB=-Y(PO-=SUB=-4-=/SUB=-)-=SUB=-3-=/SUB=-, по отдельности и одновременно легированном ионами Tb-=SUP=-3+-=/SUP=- и Tm-=SUP=-3+-=/SUP=-

In this work the optical spectroscopy and the energy transfer processes involving the Tb3+and Tm3+ ions, have been studied in eulytite double phosphate hosts of the type Sr3Y(PO4)3 doped with various amounts of the two Ln ions. It has been found that several energy transfer and cross-relaxation processes are active in this class of materials, upon excitation in the 5D4 level of Tb, and in the 1G4 one of Tm. In particular, a Tb→Tm transfer of excitation has been found to quench strongly the 5D4 level of Tb. This process occurs with a transfer efficiency increasing from 0.08 to 0.62, for a donor concentration of 2 mol%, and an acceptor concentration increasing from 2 to 15 mol%. The emission spectra are strongly affected by the presence of Tb⟷Tm energy transfer, and Tm→Tm cross relaxation processes.