bluuebunny/crossref_metadata_2025_split huggingface dataset:
Strict Positivity for the Principal Eigenfunction of Elliptic Operators with Various Boundary Conditions
Authors: Arendt Wolfgang , ter Elst A. F. M. , Glück Jochen 
Published: August 2020

Abstract
We consider elliptic operators with measurable coefficients and Robin boundary conditions on a bounded domain

Ω
⊂

ℝ
d

{\Omega\subset\mathbb{R}^{d}}

and show that the first eigenfunction v satisfies

v
⁢

(
x
)

≥
δ
>
0

{v(x)\geq\delta>0}

for all

x
∈

Ω
¯

{x\in\overline{\Omega}}

, even if the boundary

∂
⁡
Ω

{\partial\Omega}

is only Lipschitz continuous. Under such weak regularity assumptions the Hopf–Oleĭnik boundary lemma is not available; instead we use a new approach based on an abstract positivity improving condition for semigroups that map

L
p

⁢

(
Ω
)

{L_{p}(\Omega)}

into

C
⁢

(

Ω
¯

)

{C(\overline{\Omega})}

. The same tool also yields corresponding results for Dirichlet or mixed boundary conditions. Finally, we show that our results can be used to derive strong minimum and maximum principles for parabolic and elliptic equations.
Aktuelle Entwicklungen an den österreichischen Bibliotheken 2019
Authors: Bauer Bruno 
Published: August 2020

Zusammenfassung
Im vorliegenden Beitrag wird über aktuelle Projekte und Trends im österreichischen Bibliothekswesen im Jahr 2019 berichtet. Vorgestellt werden Verbundprojekte und Kooperationsprojekte österreichischer Bibliotheken, aktuelle Projekte der Österreichischen Nationalbibliothek und des Forums Universitätsbibliotheken Österreichs. Angesprochen werden auch Themen wie Forschungsdaten, Open Access, NS-Provenienzforschung, Bibliotheksausbildung, Tagungen und Publikationen der Vereinigung Österreichischer Bibliothekarinnen und Bibliothekare sowie Bibliotheks- und Informationspolitik in Österreich.
Der Kosmos eines dritten Ortes
Authors: Degkwitz Andreas 
Published: August 2020

Zusammenfassung
Im Zuge des digitalen Wandels sind Bibliotheken in der Situation, tiefgreifende Innovationsherausforderungen aufzugreifen und in ihren Serviceportfolios zu realisieren. Dabei reichen die Konzepte weit über die wechselseitigen Einflüsse analoger und digitaler Medien hinaus. Vielmehr geht es um neue Bibliotheksmodelle, wie die des „dritten Ortes“ oder der „Lernräume“. Dabei stellt sich die Frage, inwieweit sich Bibliotheken mit solchen Weiterentwicklungen tatsächlich neu erfinden oder ob sie Modelle aufgreifen, die in der Vergangenheit bereits praktiziert wurden. Aktuell spielt das Thema „Openness“ eine große Rolle für Bibliotheken, das mit „Open Access“ seinen Anfang nahm, inzwischen aber deutlich darüber hinausgeht. Mit Buchbeständen, die oft weit in die Vergangenheit zurückreichen, hat der „dritte Ort“ der Bibliothek aber auch etwas, das als gegenläufig zu unserer fortschrittsorientierten Zeit zu begreifen wie auch zu begrüßen ist.
Infrastrukturentwicklung für digitale Editionen am Beispiel der Universität Zürich: Herausforderungen, Erfahrungen und Perspektiven
Authors: Malits Andrea 
Published: August 2020

ZusammenfassungFür die nachhaltige Verfügbarkeit von Forschungsdaten im Allgemeinen und von digitalen Editionen im Besonderen fehlt es in der Schweiz nach wie vor an Infrastrukturen. Neben technischen Lösungen gelten Koordination und ein verlässliches Netzwerk von Dienstleistungen als Gelingensvoraussetzung für die nachhaltige Verfügbarkeit von Daten. Im Jahr 2014 publizierte der Schweizerische Nationalfonds (SNF) neue Fördermöglichkeiten für digitale Editionsprojekte im Rahmen der Infrastrukturförderung und initiierte damit Strukturbildungsprozesse auf lokaler und auch nationaler Ebene. Zu den wichtigsten Voraussetzungen einer möglichen Förderung zählte entsprechend die Vorlage eines Konzepts zur Gewährleistung der langfristigen Verfügbarkeit der digitalen Edition. Die Frage der Sicherstellung der digitalen Langzeitverfügbarkeit im Rahmen eines Konzepts adressierte auch Hochschulen und Gedächtnisinstitutionen bzw. deren Rolle und Verantwortlichkeit. Vor diesem Hintergrund schlossen sich vier Editionsprojekte der Universität Zürich (UZH), die Zentralbibliothek Zürich (ZB) sowie die auf Forschungs-IT spezialisierte Abteilung S3IT der UZH zusammen und erarbeiteten ein Kooperationskonzept. Der Artikel beleuchtet diese neuen Kooperationsstrukturen, schildert den Status quo und skizziert mögliche nächste Schritte auf dem Weg zu einer lokal und national koordinierten Infrastrukturlösung für digitale Editionen.
“To begin, at the beginning [...]“
Authors: Strauch Annette 
Published: August 2020

Zusammenfassung
Der Artikel1 beschreibt, wie das Forschungsdatenmanagement innovativ in der Universitätsbibliothek Hildesheim umgesetzt worden ist, auch welcher langfristige Nutzen daraus entstanden ist. Ständige Kollaborationen mit den relevanten Akteuren im Forschungsdatenmanagement in der Welt sind dabei präsent. Seit über einem Jahr (Stand: Mai 2020) gibt es Beratungen, Coffee Lectures, Workshops und andere Veranstaltungen, die bei der Umsetzung der neuen digitalen Aufgaben ganz forschungsnah helfen.
Open Access im Blick! Mehr Sichtbarkeit von Open-Access-Publikationen in der Bibliothek – Projekt visOA
Authors: Geith Uwe , Kraß Thomas 
Published: August 2020

Zusammenfassung
Um Open-Access-Publikationen stärker in den Wahrnehmungsbereich der Bibliotheksbenutzer zu bringen, ist es notwendig, sie besser sichtbar zu machen. Im visOA-Projekt, das von der NTNM-Bibliothek des INM durchgeführt wurde, wurden Open-Access-Publikationen sowohl im OPAC als auch im Discovery-System und in den Publikationslisten des INM deutlich hervorgehoben. Eine selbstprogrammierte virtuelle Zeitschriftenanzeige (VIDIJO)1 bietet eine fachspezifische Auswahl von Open-Access-Zeitschriften. Die Wirksamkeit der im Projekt ergriffenen Maßnahmen wurde durch Begleitforschung überprüft.
(Digitale) Medienkompetenz in der Stadtbibliothek Kreuztal – Ein Blick in das Projekt „Wissen, Können, Machen“
Authors: Escher-Schenkschuck Annamarie , Flecke Sabine 
Published: August 2020

Zusammenfassung
Digitale Medienkompetenz ist weiterhin ein wichtiger Faktor in der Arbeit einer Öffentlichen Bibliothek. Die Stadtbibliothek Kreuztal hat ein Angebot entwickelt, das alle Altersgruppen erreichen soll und dessen Fokus es ist, digitale Medien nicht nur zu konsumieren, sondern sie zu verstehen, selbst zu gestalten und einen Bezug zu ihnen herzustellen. Die Voraussetzungen, Motivationen, Angebote und Umsetzungsstrategien werden im Folgenden beschrieben.
The impact of a peer-facilitated discussion initiative on international students’ learning experience in the context of internationalisation at home
Authors: Jeanneau Catherine , O’Riordan Stéphanie 
Published: August 2020

Abstract
Fostering skills development is one of the tenets of education. For a long time, the traditional binary teacher-student interaction was used as the sole approach to teaching and learning but it is now overwhelmingly regarded as insufficient. The present paper reports on an initiative based on the principles of peer learning. The discussion groups and one-to-one sessions in languages, facilitated by native speakers (NS) who are international students in the institution, were set-up to enable language learners to develop their oral skills. While the advantages of the activity for language learners are clear, it is not as easy to determine the benefits for the NS peer-facilitators. The study presents findings from questionnaires and interviews conducted with some of these NS peer-facilitators and discuss the reported impact of the initiative on these students. While personal growth and development of intercultural awareness feature strongly in the data analysis, an enhanced language learning experience and an influential factor in some participants’ educational and career paths are also revealed. These findings are explained with reference to relevant developments in the study abroad, volunteering and peer learning literature. We will conclude that the initiative is a positive tool for international students’ integration into the host institution and offers a novel way for them to socialise and engage in their new learning environment.
Research on Innovation Signals and Feedbacks between SMEs and the Government
Authors: Feng Xiao , Meng Weidong , Huang Bo 
Published: August 2020

Abstract
Due to the financing constraint that faced by small and medium-sized enterprises (SMEs), SMEs are more cautious in innovation investments, and thus more eager to gain external financial support. This paper discusses the impact of SMEs’ R&D investment on government subsidy under the constraint of hidden information. It adopts a modified endogenous switching regression model to solve the endogenous problems. The results show that SME’s initiative to signal its underlying innovative capacity has an important impact on Chinese government’s subsidy feedback. SMEs that send high-type signals have gained more subsidies. And when SMEs are with different types of innovation signals, they would have different influence mechanisms on subsidy feedback. This study concludes that the policymakers should make more use of its belief and give effective feedbacks to the entrepreneurs.
Functionality and reliability of horizontal control net (Poland)
Authors: Wolski Bogdan , Granek Grzegorz 
Published: August 2020

Abstract
Horizontal control networks established with monuments are functional if the conditions related to the number of control points, their density, condition and stability of coordinates are met. For functionality defined in those terms, deterministic accuracy characteristics are of little use. The subject matter discussed herein includes the two key features of geodetic control points, i.e., usability and stability. Due to the varying properties of those variables and the impact of the operating time of the system, there is no alternative to reliability-based approach in developing the functionality model. The measures of functionality and the procedures of data acquisition for developing the model of the control network destruction process have been defined. The solution presented herein is relevant for geodetic practice, providing a standard procedure for defining the time frame and the scope of the control network upgrading. The identified destruction process model optimizes this task assuming critical states expressed by the functionality probability. The applied approach is an example of the reliability theory-based approach typical for engineering. The issue of simulating the destruction process is illustrated with the results of the tests of class 3 control networks conducted in Kielce and Lodz regions in Poland. As a result of the tests, the characteristic properties of the control network destruction process have been identified. It was also shown how the patterns of usability and accuracy of the geodetic control points are relevant on the stage of implementing investment project tasks.
Pore-scale gas–water flow in rock: Visualization experiment and simulation
Authors: Wu Feng , Yao Cong , Cong Linlin , Xi Yanping 
Published: August 2020

Abstract
The characteristics of pore-scale two-phase flow are of significance to the effective development of oil and gas resources, and visualization has gradually become one of the hot spots in the research of pore-scale two-phase flow. Based on the pore structure of rock, this research proposed a microscopic glass etching displacement experiment and a Navier–Stokes equation based finite element simulation to study the pore-scale gas–water two-phase flow. Then, this research conducted the proposed methods on the type I, type II and type III tight sandstone reservoirs in the Penglaizhen Formation of western Sichuan Basin, China. Results show that the outcomes of both the microscopic glass etching displacement experiment and the finite element simulation are by and large consistent. The water distributed in the large pores is displaced, and the trapped water mainly exists in the area induced by flow around high-permeability pores, perpendicular pores and disconnected ends of pores. The microscopic glass etching displacement experiment is conducive to better observing the phenomenon of a viscous finger-like breakthrough and air jumps in migration flows in narrow throats, while the finite element simulation has the advantages of cost effectiveness, easy operation and strong experimental reproducibility.
Microscopic mechanism of sandstone hydration in Yungang Grottoes, China
Authors: Chen Jiawei , Xu Jinming , Huang Jizhong 
Published: August 2020

AbstractThe macroscopic engineering properties of sandstone are dominated primarily by mineral features in a microscopic scale. This study will investigate the microscopic physical and mechanical properties of the main minerals (quartz, K-feldspar, Na-feldspar and kaolinite) in Yungang Grottoes sandstone, using the molecular mechanics and the molecular dynamics simulations. The microscopic physical properties were represented by density and volume. The microscopic mechanical properties were represented by Young’s modulus and Poisson’s ratio. The microscopic mechanical properties of the minerals in various directions were then explored. The influences of water molecules and the surrounding temperature on the microscopic physical and mechanical properties of the minerals were furthermore investigated. It is found that the differences in the microscopic densities between the simulated results and those from the open data set are, respectively, 0.37%, 1.15% and 9.16%, for the quartz, Na-feldspar and kaolinite cells; the microscopic mechanical properties of various minerals have a significant anisotropy; the Young’s modulus of halloysite decreases by 75.86% compared with that of kaolinite; as the water molecule number increased from 0 to 5, the Young’s moduli of K-feldspar, Na-feldspar and kaolinite cells decreases by 31.31%, 55.05% and 42.60%, respectively; for each mineral, as the temperature increases from 243.15 to 303.15 K under one atmospheric pressure, the volume increases and the density decreases. Those results may have a theoretical significance for the analysis of microscopic mechanism of hydration in the Yungang Grottoes sandstone.
An ABC-optimized fuzzy ELECTRE approach for assessing petroleum potential at the petroleum system level
Authors: Hamzeh Mohamad , Karimipour Farid 
Published: August 2020

AbstractAn inevitable aspect of modern petroleum exploration is the simultaneous consideration of large, complex, and disparate spatial data sets. In this context, the present article proposes the optimized fuzzy ELECTRE (OFE) approach based on combining the artificial bee colony (ABC) optimization algorithm, fuzzy logic, and an outranking method to assess petroleum potential at the petroleum system level in a spatial framework using experts’ knowledge and the information available in the discovered petroleum accumulations simultaneously. It uses the characteristics of the essential elements of a petroleum system as key criteria. To demonstrate the approach, a case study was conducted on the Red River petroleum system of the Williston Basin. Having completed the assorted preprocessing steps, eight spatial data sets associated with the criteria were integrated using the OFE to produce a map that makes it possible to delineate the areas with the highest petroleum potential and the lowest risk for further exploratory investigations. The success and prediction rate curves were used to measure the performance of the model. Both success and prediction accuracies lie in the range of 80–90%, indicating an excellent model performance. Considering the five-class petroleum potential, the proposed approach outperforms the spatial models used in the previous studies. In addition, comparing the results of the FE and OFE indicated that the optimization of the weights by the ABC algorithm has improved accuracy by approximately 15%, namely, a relatively higher success rate and lower risk in petroleum exploration.
The Cretaceous igneous rocks in southeastern Guangxi and their implication for tectonic environment in southwestern South China Block
Authors: Liu Yang , Fang Nianqiao , Qiang Menglin , Jia Lei , Song Chaojie 
Published: August 2020

Abstract
Southeastern Guangxi is located in the southwestern South China Block and to the northwest of the South China Sea (SCS), with abundant records of the Cretaceous magmatism. A detailed study of igneous rocks will contribute to a better understanding of the late Mesozoic tectonic environment. Zircon U–Pb dating yields ages of 93.37 ± 0.43 Ma for Yulin andesites and 107.6 ± 1.2 Ma for Luchuan granites. Yulin andesites are hornblende andesites, of which w(MgO) is between 7.72% and 8.42%, and Mg# is between 66.7 and 68.0, belonging to high magnesian andesites (HMAs) from peridotite sources. Luchuan granites are medium- to fine-grained monzogranites. Monzogranites and clastoporphyritic lava are high-K calc-alkaline series and metaluminum to weakly peraluminous series, which belong to the I-type granites. Those are enriched in Rb, Th, K and LREEs and depleted in Nb, Ta, P and Eu, showing the geochemical characteristics related to subduction. Unlike the contemporary “bimodal igneous rock assemblages” in Zhejiang and Fujian, the intermediate-acid magmatites in the southeastern Guangxi imply the compressive tectonic environment. The assemblage of HMAs and adakitic rocks indicates that the southwestern South China Block was under the Neo-Tethyan subduction during Cretaceous, and slab melting contributed to the magma in this area.
Intergeneric hybidization of sunflower (Helianthus annuus L.) with spiny plumeless thistle (Carduus acanthoides L.)
Authors: Hristova-Cherbadzhi Miroslava 
Published: August 2020

Abstract

Carduus acanthoides L (spiny plumeless thistle) a biannual wild species with 2n = 22 chromosomes was crossed with Helianthus annuus L. When crossing, pollen from C. acanthoides germinated and pollinated the stigmas of sunflower lines HA 89A after 48 h. The crossability rate was low, but seeds and hybrid plants were obtained. The F1 plants strongly resembled the cultivated sunflower with the most important bio-morphological characters, even though they had an intermediate type of heritability. The hybrid nature was confirmed by RAPD markers. The polymorphism between H. annuus, C. acanthoides, and their F1 hybrids was studied using RAPD. The result showed introgression of C. acanthoides in the hybrid progeny. It was established that the wild species carried Rf genes for the CMS PET-1. After self-pollination and sib-pollination of the F1 plants and back-crossing with cultivated sunflower, F2, BC1 and next generation hybrid progenies were obtained. The investigation encompassed the period 2000–2007 and 2014–2018. Some of the new lines have been included in a heterosis breeding program for developing hybrids for the sunflower market.
Periodontal status and bone metabolism in women in reproductive and postmenopausal periods
Authors: Mazur Iryna , Dilbarkhanov Bassymbek , Kuracha Xeniya , Novoshytskyy Volodymyr , Suprunovych Iryna , Zhakipbekov Kairat 
Published: August 2020

Abstract

Objectives
Chronic periodontitis is one of the most common diseases in the world. Periodontitis occurs more frequently in postmenopausal women due to hormonal changes and in patients with osteoporosis. Thus, the aim of our study was to compare levels of alveolar bone loss of mandible and maxilla and bone tissue remodeling markers in women of reproductive and postmenopausal periods.

Methods
Fifty-nine women aged 25–68 years were enrolled in a cross-sectional study and divided into two groups. Group I consisted of 42 women of reproductive age and Group II included 17 women in their postmenopausal period. The level of alveolar bone loss of mandible and maxilla was assessed using dental panoramic radiography, and the level of bone remodeling markers (Beta C-terminal telopeptide of type I collagen [β-CTx] and osteocalcin) was obtained in both groups.

Results
Women in the postmenopausal period have higher level of alveolar bone loss in mandible and maxilla than women of reproductive age. The level of ß-CTx and osteocalcin was significantly higher in Group II, compared to Group I (p=0.002 and p=0.005, respectively).

Conclusions
In postmenopausal women, on the background of significantly higher bone remodeling, an increase of alveolar bone loss of mandible and maxilla was observed.
Detection of coherent groups using measured signals, in an inter-area mode, for creating controlled islands to protect the power system from blackout
Authors: Mandadi Kalyani , Boddeti Kalyan Kumar 
Published: August 2020

Abstract
Controlled islanding is an effective way of preventing the system from catastrophic blackouts. This is generally solved either as a constrained combinatorial optimization problem or a slow coherency based linearized approach. The combinatorial explosion of the solution space of an extensive power network increases the complexity of solving, while the linearized slow coherency approach cannot track the varying coherent generator groups with a change in system operating conditions. Offline coherent studies are utilized in wide area measurement system (WAMS) data-based approaches to determine islanding boundaries. So, the present study proposes a novel coherency based controlled islanding technique that clusters generators and load buses simultaneously from the measured signals, ensuring generator coherency. Therefore, identification of inter-area modes from bus voltage angle signals is necessary to determine coherent bus groups. So, Zolotarev polynomial based filter bank (ZPBFB) is adopted in the present work to determine inter-area modes. The dimensional reduction techniques are used to cluster the coherent buses. The bus clusters thus obtained with the proposed method are compared with bus clusters determined from small signal stability analysis. The proposed method is demonstrated on IEEE 39-bus, 68-bus and 118-bus test systems and compared with graph spectra based controlled islanding.
Experimental control of photovoltaic system using neuro – Kalman filter maximum power point tracking (MPPT) technique
Authors: Boutabba Tarek , Drid Said , Chrifi-Alaoui Larbi 
Published: August 2020

Abstract
This paper proposes a new maximum power point tracking (MPPT) technique of photovoltaic system based on Kalman filter (KF) and associate to Artificial Neural Networks (ANN). The design process of photovoltaic (PV) modules can be greatly enhanced by using advanced and accurate models. Furthermore, the use of a neural model especially for accuracy improvement of the electrical equivalent circuit parameters, where the analytic equation of the model cannot be easily expressed, because the relationship between parameters is nonlinear. The proposed neural network is trained once by using some measured I-V and P-V curves and to keep in account the change of all the parameters at different operating conditions. For that reason, to get the fast tracking performance on this noisy conditions, and to maximize the power of photovoltaic system a KF method have been used. The performance analysis of perturb and observe (P&O) and KF MPPT techniques has been simulated in MATLAB/Simulink software and their model and control schemes has been analyzed and validated.