bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of mode coupling on three spatially multiplexed channels in multimode graded index plastic optical fibers
Authors: Savović S , Djordjevich A , Simović A , Drljača B 
Published: October 2020

Abstract
The influence of mode coupling on three-channel spatial division multiplexing capability in multimode graded index plastic optical fibers is investigated by solving the power flow equation. Our numerical results show that mode coupling significantly limits the fiber length at which the spatial division multiplexing can be realized with a minimal crosstalk between three neighbor spatial optical channels. Three spatial channels in the multimode graded index plastic optical fiber can be employed with a minimal crosstalk up to the fiber length of 3.5 m, which is about 12.5% of the coupling length (fiber length where equilibrium mode distribution is achieved). Such characterization of multimode graded index plastic optical fibers should be considered in designing an optical fiber transmission system for space division multiplexing, particularly for small office networking.
The difference logical operation for images in optical echo holography
Authors: Akhmedshina E N , Sakhbieva A R , Nefediev L A , Nefedyev Y A , Andreev A O 
Published: October 2020

Abstract
In this paper, we consider the implementation of logical operations on images using the accumulated long-lived echo hologram. It is shown that the accumulated echo hologram could be used for the implementation of the set difference logical operation.
Far off-shore wind energy-based hydrogen production: Technological assessment and market valuation designs
Authors: Woznicki M , Le Solliec G , Loisel R 
Published: October 2020

Abstract
This article provides a techno-economic study on coupled offshore wind farm and green hydrogen production via sea water electrolysis (OWF-H2). Offshore wind energy, wind farms (OWF) and water electrolysis (WE) technologies are described. MHyWind (the tool used to perform simulations and optimisations of such plants) is presented, as well as the models of the main components in the study. Three case studies focus on offshore wind farms, either standalone or connected to the grid via export cables, coupled with a battery and electrolysis systems either offshore or onshore. Exhaustive searches and optimisations performed allowed for rules of thumb to be derived on the sizing of coupled OWF-H2 plants, that minimize costs of hydrogen production (LCoH2, in €/kgH2): Non-connected OWF-H2, coupled to a battery, offers the lowest LCoH2, without the costs of H2 transportation, when compared to cases where the WE is installed onshore and connected to the OWF. Using a simple power distribution heuristic, increasing the number of installed WE allows the system to take advantage of more OWF energy but doesn’t improve plant efficiency, whereas a battery always does. Finally, within the scope of this study, it is observed that power ratios of optimized plant architectures (leading to the lowest LCoH2) are between 0.8-0.9 for PWE/POWF and 0.3-0.35 for PBattery/POWF.
Applications and platforms in digitalisation of wind farm O&M – community feedback and survey results
Authors: Berkhout V , Machill B , Reintanz L 
Published: October 2020

Abstract
Achieving performance optimisation and cost savings by advanced data analysis techniques and improved digital communication is a significant focus of wind farm operators and research organisations often framed under the terms IoT or Industry 4.0. Within the research project ‘ModernWindABS’, Fraunhofer IEE has conducted a twofold approach to identify new applications using modern methods that will innovate operation and maintenance processes. Based on a systematic structure of O&M processes and mathematic methods, innovative applications were identified and evaluated in expert workshops. Separately a survey among wind industry professionals with the focus on innovative applications through digital platforms has been conducted in partnership with German industry associations. From both approaches, applications, that enable failure risk monitoring, turn out as the highest priorities from the professionals consulted. Additionally, the survey results yield insights on participants’ expectations on benefits and financial contribution per organisational role and preferences regarding the platform setup and points out gaps between these expectations and current platform service designs. It further identifies the main barriers to the broader use of platforms, of which organisational and legal obstacles seem to outweigh technical problems.
On Stochastic Reduced-Order and LES-based Models of Offshore Wind Turbine Wakes
Authors: Paskyabi Mostafa Bakhoday , Krutova Maria , Nielsen Finn Gunnar , Reuder Joachim , Guernaoui Omar El 
Published: October 2020

Abstract
In this paper, the primary objective is to investigate flow structures in the wake of wind turbines based on applying a truncated Proper Orthogonal Decomposition (POD) approach. This scheme decomposes the three-dimensional velocity fields produced by the high-fidelity PArallelized LES Model (PALM) into a number of orthogonal spatial modes and time-dependent weighting coefficients. PALM has been combined with an actuator disk model with rotation to incorporate the effects of a turbine array. The time-dependent deterministic weights from applying the POD scheme are replaced by stochastic weights, estimated from two independent stochastic techniques that aim to account for unresolved small-scale features for a number of POD modes. We then reconstruct the flow field by a small number of stochastic modes to investigate how well the applied stochastic methodologies can reproduce the flow field compared to the original LES results.
A Numerical Study on the Effect of Wind Turbine Wake Meandering on the Power Production of Hywind Tampen
Authors: Tenggren Endre , Erik Olsen Lars , Andr`e Johansen Daniel , Bracchi Tania 
Published: October 2020

Abstract
The purpose of the study is to show the importance of wake meandering effect with regard to power production, in terms of annual energy production (AEP), and velocity deficit for wind turbines affected by wake meandering. A simplified economical and environmental analysis is also presented. A replica of Equinor’s layout for Hywind Tampen wind farm, referred to as the original layout, is made and used as a basis for comparison. An alternative configuration is produced through a pragmatical optimization process, applying the SIMA-DIWA software, which reduces the effect of wake meandering on the downstream wind turbines, when the wind approaches from the most frequent direction. To show the aerodynamic effects of applying greater spacing between turbines, an enhanced version of Hywind Tampen is also presented. The main findings of the project correlate greater wake effect meandering for wind turbine configurations spread over a smaller area. The estimated annual energy production for the three configurations is 488.5 GWh for the original, 497.6 GWh for the up-scaled and 486.2 GWh for the alternative configuration, respectively. Furthermore, the optimization process revealed that a reduction in turbine distance can contribute to reduced wake effect in particular cases.
Observations from hydrodynamic testing of a flexible, large-diameter monopile in irregular waves
Authors: Bachynski E E , Thys M , Dadmarzi F H 
Published: October 2020

Abstract
As the offshore wind industry moves toward larger wind turbines and deeper water, wave-induced loads on large-diameter monopiles are of increasing importance for ultimate limit state design checks. The combination of a relatively large diameter with steep waves in intermediate water depth presents challenges for numerical methods, and small-scale hydrodynamic testing of monopiles is therefore a necessary step in reducing the uncertainties in numerical analyses. Here, we aim to summarize the experimental observations in a new set of tests carried out with a flexible monopile wind turbine, and to understand the similarities and differences between these results and previous studies. Compared to previous studies, the present tests consider a larger monopile diameter and hub height, and include a larger number of realizations and repetitions. The distribution of extreme values and the contributions from different structural modes are studied. These experimental results provide insight into the physical effects which must be accurately captured by numerical tools that are used in design.
Our Moment of Truth: The Social Contract Realized?
Authors: Lubchenco Jane , Rapley Chris 
Published: October 2020

Abstract
Much has changed in the two decades since I (JL) proposed that scientists should re-examine their obligations to society in order to serve society better. Today, more environmental scientists are actively sharing their science broadly, conducting use-inspired science (sensu Stokes) in addition to basic science, engaging with society, and crafting solutions to problems not just diagnosing them—all very welcome and exciting developments. For the most part, however, environmental scientists have taken on these extra duties because they believed it was the right thing to do and despite the considerable impediments that exist within academia. But make no mistake, the culture of academia continues to impede progress. As a result, although the above actions have had demonstrable effect, their collective impact falls far short of what is needed if society is to tackle effectively the disruption underway due to climate change, ocean acidification, biodiversity loss, pandemics, and more. Actions by individuals can take us only so far. To truly help society meet its grand challenges, environmental scientists must now make a quantum leap in engagement with society. It is time for strategic, collective action to change the culture of academia and create the enabling conditions for science to serve society better.
Vascular plant species response to warming and elevated carbon dioxide in a boreal peatland
Authors: McPartland Mara Y , Montgomery Rebecca A , Hanson Paul J , Phillips Jana R , Kolka Randy , Palik Brian 
Published: October 2020

Abstract
Peatlands store a significant amount of terrestrial organic carbon in plant biomass and soils. The Spruce and Peatland Responses Under Changing Environments (SPRUCE) project is a warming and elevated carbon dioxide (eCO2) experiment designed to test how the carbon sequestration and storage capacity of peatland ecosystems will respond to climate change. Here, we report changes in the vascular plant community that have occurred during the first five years of SPRUCE. We tracked species composition, diversity, and aboveground net primary production (ANPP) in chambers warmed at a wide range of temperatures (+0, +2.25, +4.5, +6.75, +9 °C), and two CO2 levels (~400 [ambient] and 900 parts per million). We observed an increase in aboveground vascular plant biomass accumulation, due primarily to an increase in shrub abundance. Overall species diversity decreased substantially, likely due in part to shading by increases in shrub density. The main driver of change in the vascular plant community was temperature, with minimal effects of CO2 evident. These results indicate an overall increase in ANPP with warming, but highlight the importance of interactions between direct (warming) and indirect (competition) effects in determining how boreal peatlands will respond to climate change.
What explains the variation in dam impacts on riverine macroinvertebrates? A global quantitative synthesis
Authors: Wang Jun , Ding Chengzhi , Heino Jani , Jiang Xiaoming , Tao Juan , Ding Liuyong , Su Wan , Huang Minrui , He Daming 
Published: October 2020

Abstract
Dams have fragmented rivers and threatened aquatic biodiversity globally. However, the findings regarding dam impacts on riverine macroinvertebrates vary across regions and taxa. We conducted a global meta-analysis to quantify the effects of dams on macroinvertebrate assemblages (i.e. species richness and abundance) based on 3849 data points extracted from 54 publications. Responses of macroinvertebrates to dams varied among climatic zones, dam altitudes, dam sizes (i.e. height), downstream distances from the dams, and taxonomic groups. The overall effect size of dams on macroinvertebrate richness was negative, while that of dams on abundance was positive but varied among different dam types. Richness reductions were most pronounced in cold regions and high-altitude regions and were least pronounced in tropical regions and low-altitude regions, while abundance increases were more obvious in tropical regions and low-altitude regions. Macroinvertebrate richness reduction and abundance increase were coupled (i.e. when the richness slightly decreased, the increase in abundance was more significant, and vice versa) under the influence of dams across different climatic zones, altitudes, dam heights, and downstream distances from the dams. Furthermore, different taxonomic groups responded variably to dams, with stoneflies (Plecoptera), caddisflies (Trichoptera) and true bugs (Hemiptera) being the most sensitive groups (i.e. significant reduction in richness) among the taxa examined. Macroinvertebrate richness reductions were primarily attributed to changes in downstream substrate composition (i.e. from coarse to fine substrates), while abundance increases were potentially caused by replacements among taxa at downstream sites. Collectively, our results contribute to improving the prediction of the effects of dams on riverine macroinvertebrate assemblages and are valuable for guiding assessment and monitoring of river ecosystems, as well as sustainable dam development, planning and restoration.
Holocene peat humification and carbon dynamics in the Westerlies-influenced Northwest China
Authors: Li Yinbo , Chen Liang , Ran Min 
Published: October 2020

Abstract
Understanding peat carbon dynamics in the past is of significance, given the uncertainties as to whether there will be an increase or a reduction in carbon as a result of future climate change. Studies of peat carbon dynamics have primarily been conducted in monsoon-influenced China. However, data relating to carbon dynamics in peat deposits has not yet been investigated in Westerlies-influenced Northwest China (NWC). In this study, the Holocene carbon accumulation rate (CAR) is explored at the Tuolehaite peat core, with a mean rate of growth of 2.4 yr mm−1, 0.4 mm yr−1, in the high-elevation Altai Mountains within NWC. Its CAR shows a decreasing trend, ranging from 4.8 to 68.8 g C m−2 yr−1, with a mean of 28.0 g C m−2 yr−1 since the Holocene epoch. Comparisons of the CAR in the Westerlies-influenced NWC with that in the monsoon-influenced Qinghai-Tibetan Plateau, Northeast China, and South China, reveal that the Holocene CAR trend in relatively high-elevation peat deposits (e.g. Tuolehaite Peat and Hongyuan Peat) is opposite to that found in relatively low-elevation peat deposits (e.g. Hani Peat and Dahu Peat). Different driving factors (temperature and precipitation) of CAR could be responsible for these opposing trends. To be specific, temperature is the main driving factor influencing the CAR in relatively high-elevation peat deposits, whereas precipitation is the key driving factor controlling the CAR in relatively low-elevation peat deposits. Our work indicates that comprehensive investigations into peat CARs in both Westerlies-influenced and monsoon-influenced regions contribute to an understanding of the peat CAR pattern in China as a whole.
Effects of cooling method and elements segregation on the martensite-pearlite banded structure of high carbon bearing steel
Authors: Wang Yun-long , Yu Wei , Chen Yin-li 
Published: October 2020

Abstract
In this study, the effects of the cooling method and alloying element segregation on the abnormal zonal structure of high-carbon bearing steel were investigated by reheating, controlled rolling, and controlled cooling of the sample. The microstructure and alloy segregation characteristics of the abnormal strip structure in the hot-rolled plate of the steel were revealed by optical microscopy, scanning electron microscopy, transmission electron microscopy, and electron probe x-ray microanalysis. The JMatPro thermodynamic software was used to examine the relationship between the alloy elements and banded structure defects of the hot-rolled sheet and analyse the causes of the defects and their elimination methods. The results show distinct positive segregation of Cr/Mn and negative segregation of C in martensite–pearlite banded structure defects in hot-rolled plates. The martensite–pearlite banded structure is formed by the interaction between the cooling rate and the segregation of alloying elements after hot rolling. Studies have found that segmented cooling (slow cooling–air cooling) can eliminate the martensite–pearlite banded structure.
Bi2Se3, Bi2Te3 quantum dots-sensitized rutile TiO2 nanorod arrays for enhanced solar photoelectrocatalysis in azo dye degradation
Authors: Zhou Guanda , Zhao Ting , Wang Oumin , Xia Xin , Pan Jia Hong 
Published: October 2020

Abstract
Rutile TiO2 nanorod arrays vertically aligned on conductive fluorine-doped tin oxide glass are optimized for photocatalysis in terms of the density and diameter of nanorods by tuning the concentration of Ti precursor and reaction time during the hydrothermal process. Quantum dots (QDs) of V2VI3( V = Bi; VI = Se, Te) topographic insulators are then employed as sensitizers to enhance the visible-light response of TiO2. Electrochemical measurements show that the decoration of Bi2Se3 or Bi2Te3 significantly increases the photocurrent due to the enhanced light harvesting properties and the charge carrier separation capability mediated by the topographic isolation effect of V2VI3 QDs. Photoelectrocatalytic (PEC) activity evaluation is conducted towards the decoloration of azo dyes, including methyl orange and methylene blue under the sunlight irradiation. The elaborated Bi2Se3/TiO2 nanorod array exhibits the superior PEC performances, presenting shows great potentials in environmental remediation.
How do we share data in COVID-19 research? A systematic review of COVID-19 datasets in PubMed Central Articles
Authors: Zuo Xu , Chen Yong , Ohno-Machado Lucila , Xu Hua 
Published: October 2020

Abstract

Objective
This study aims at reviewing novel coronavirus disease (COVID-19) datasets extracted from PubMed Central articles, thus providing quantitative analysis to answer questions related to dataset contents, accessibility and citations.

Methods
We downloaded COVID-19-related full-text articles published until 31 May 2020 from PubMed Central. Dataset URL links mentioned in full-text articles were extracted, and each dataset was manually reviewed to provide information on 10 variables: (1) type of the dataset, (2) geographic region where the data were collected, (3) whether the dataset was immediately downloadable, (4) format of the dataset files, (5) where the dataset was hosted, (6) whether the dataset was updated regularly, (7) the type of license used, (8) whether the metadata were explicitly provided, (9) whether there was a PubMed Central paper describing the dataset and (10) the number of times the dataset was cited by PubMed Central articles. Descriptive statistics about these seven variables were reported for all extracted datasets.

Results
We found that 28.5% of 12 324 COVID-19 full-text articles in PubMed Central provided at least one dataset link. In total, 128 unique dataset links were mentioned in 12 324 COVID-19 full text articles in PubMed Central. Further analysis showed that epidemiological datasets accounted for the largest portion (53.9%) in the dataset collection, and most datasets (84.4%) were available for immediate download. GitHub was the most popular repository for hosting COVID-19 datasets. CSV, XLSX and JSON were the most popular data formats. Additionally, citation patterns of COVID-19 datasets varied depending on specific datasets.

Conclusion
PubMed Central articles are an important source of COVID-19 datasets, but there is significant heterogeneity in the way these datasets are mentioned, shared, updated and cited.
Inferring TF activities and activity regulators from gene expression data with constraints from TF perturbation data
Authors: Ma Cynthia Z , Brent Michael R 
Published: October 2020

Abstract

Motivation
The activity of a transcription factor (TF) in a sample of cells is the extent to which it is exerting its regulatory potential. Many methods of inferring TF activity from gene expression data have been described, but due to the lack of appropriate large-scale datasets, systematic and objective validation has not been possible until now.

Results
We systematically evaluate and optimize the approach to TF activity inference in which a gene expression matrix is factored into a condition-independent matrix of control strengths and a condition-dependent matrix of TF activity levels. We find that expression data in which the activities of individual TFs have been perturbed are both necessary and sufficient for obtaining good performance. To a considerable extent, control strengths inferred using expression data from one growth condition carry over to other conditions, so the control strength matrices derived here can be used by others. Finally, we apply these methods to gain insight into the upstream factors that regulate the activities of yeast TFs Gcr2, Gln3, Gcn4 and Msn2.

Availability and implementation
Evaluation code and data are available at https://doi.org/10.5281/zenodo.4050573.

Supplementary information
Supplementary data are available at Bioinformatics online.