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- ItemTrend detection in river flow indices in Poland(Heidelberg : Springer, 2018) Piniewski, Mikołaj; Marcinkowski, Paweł; Kundzewicz, Zbigniew W.The issue of trend detection in long time series of river flow records is of vast theoretical interest and considerable practical relevance. Water management is based on the assumption of stationarity; hence, it is crucial to check whether taking this assumption is justified. The objective of this study is to analyse long-term trends in selected river flow indices in small- and medium-sized catchments with relatively unmodified flow regime (semi-natural catchments) in Poland. The examined indices describe annual and seasonal average conditions as well as annual extreme conditions—low and high flows. The special focus is on the spatial analysis of trends, carried out on a comprehensive, representative data set of flow gauges. The present paper is timely, as no spatially comprehensive studies (i.e. covering the entire Poland or its large parts) on trend detection in time series of river flow have been done in the recent 15 years or so. The results suggest that there is a strong random component in the river flow process, the changes are weak and the spatial pattern is complex. Yet, the results of trend detection in different indices of river flow in Poland show that there exists a spatial divide that seems to hold quite generally for various indices (annual, seasonal, as well as low and high flow). Decreases of river flow dominate in the northern part of the country and increases usually in the southern part. Stations in the central part show mostly ‘no trend’ results. However, the spatial gradient is apparent only for the data for the period 1981–2016 rather than for 1956–2016. It seems also that the magnitude of increases of river flow is generally lower than that of decreases.
- ItemChanges of snow cover in Poland(Heidelberg : Springer, 2017) Szwed, Małgorzata; Pin´skwar, Iwona; Kundzewicz, Zbigniew W.; Graczyk, Dariusz; Mezghani, AbdelkaderThe present paper examines variability of characteristics of snow cover (snow cover depth, number of days with snow cover and dates of beginning and end of snow cover) in Poland. The study makes use of a set of 43 long time series of observation records from the stations in Poland, from 1952 to 2013. To describe temporal changes in snow cover characteristics, the intervals of 1952–1990 and of 1991–2013 are compared and trends in analysed data are sought (e.g., using the Mann–Kendall test). Observed behaviour of time series of snow-related variables is complex and not easy to interpret, for instance because of the location of the research area in the zone of transitional moderate climate, where strong variability of climate events is one of the main attributes. A statistical link between the North Atlantic Oscillation (NAO) index and the snow cover depth, as well as the number of snow cover days is found.
- ItemWhat can we learn from the projections of changes of flow patterns? Results from Polish case studies(Heidelberg : Springer, 2017) Piniewski, Mikołaj; Meresa, Hadush Kidane; Romanowicz, Renata; Osuch, Marzena; Szczes´niak, Mateusz; Kardel, Ignacy; Okruszko, Tomasz; Mezghani, Abdelkader; Kundzewicz, Zbigniew W.River flow projections for two future time horizons and RCP 8.5 scenario, generated by two projects (CHASE-PL and CHIHE) in the Polish-Norwegian Research Programme, were compared. The projects employed different hydrological models over different spatial domains. The semi-distributed, process-based, SWAT model was used in the CHASE-PL project for the entire Vistula and Odra basins area, whilst the lumped, conceptual, HBV model was used in the CHIHE project for eight Polish catchments, for which the comparison study was made. Climate projections in both studies originated from the common EURO-CORDEX dataset, but they were different, e.g. due to different bias correction approaches. Increases in mean annual and seasonal flows were projected in both studies, yet the magnitudes of changes were largely different, in particular for the lowland catchments in the far future. The HBV-based increases were significantly higher in the latter case than the SWAT-based increases in all seasons except winter. Uncertainty in projections is high and creates a problem for practitioners.
- ItemFormation mechanism for stable hybrid clusters of proteins and nanoparticles(Washington D.C. : American Chemical Society, 2015) Moerz, Sebastian T.; Kraegeloh, Annette; Chanana, Munish; Kraus, TobiasCitrate-stabilized gold nanoparticles (AuNP) agglomerate in the presence of hemoglobin (Hb) at acidic pH. The extent of agglomeration strongly depends on the concentration ratio [Hb]/[AuNP]. Negligible agglomeration occurs at very low and very high [Hb]/[AuNP]. Full agglomeration and precipitation occur at [Hb]/[AuNP] corresponding to an Hb monolayer on the AuNP. Ratios above and below this value lead to the formation of an unexpected phase: stable, microscopic AuNP–Hb agglomerates. We investigated the kinetics of agglomeration with dynamic light scattering and the adsorption kinetics of Hb on planar gold with surface-acoustic wave-phase measurements. Comparing agglomeration and adsorption kinetics leads to an explanation of the complex behavior of this nanoparticle–protein mixture. Agglomeration is initiated either when Hb bridges AuNP or when the electrostatic repulsion between AuNP is neutralized by Hb. It is terminated when Hb has been depleted or when Hb forms multilayers on the agglomerates that stabilize microscopic clusters indefinitely.
- ItemRenegotiating Open-Access-Licences for Scientific Films(Amsterdam : IOS Press, 2016) Brehm, ElkeScientific publishing is not limited to text any more, but more and more extends also to digital audio-visual media. Thus services for publishing these media in portals designed for scientific content, oriented towards the demands of scientists and which comply with the requirements of Open Access Licenses must be provided. Among others, it is the goal of the Competence Centre for Non-textual-materials of TIB to collect, archive and provide access to scientific audio-visual media in the TIB AV-Portal under the best possible (open) conditions. This applies to older films, as for example the film collection of the former IWF Knowledge and Media gGmbH i. L. (IWF) and to new films. However, even if the acquisition of the necessary rights for audio-visual media is complex, the renegotiation of Open-Access- Licenses for older films is very successful. This paper focuses on the role of Open Access in the licensing strategy of TIB regarding scientific films, the respective experience of TIB and the presentation in the AV-Portal, but also touches upon prerequisites and procedures for the use of Orphan Works.
- ItemThe ties that bind - On the impact of losing a consortium member in a cooperatively operated digital preservation system(2016) Lindlar, MichelleCooperatively operated digital preservation systems offer institutions of varying size the chance to actively participate in digital preservation. In current times of budget cuts they are also a valuable asset to larger memory institutions. While the benefits of cooperatively operated systems have been discussed before, the risks associated with a consortial solution have not been analyzed in detail. TIB hosts the Goportis Digital Archive which is used by two large national subject libraries as well as by TIB itself. As the host of this comparatively small preservation network, TIB has started to analyze the particular risk which losing a consortium member poses to the overall system operation. This paper presents the current status of this work-in-progress and highlights two areas: risk factors associated with cost and risk factors associated with the content. While the paper is strictly written from the viewpoint of the consortial leader/ host of this specific network, the underlying processes shall be beneficial to other cooperatively operated digital preservation systems.
- ItemOverview of Chinese specialist literature in the field of Science and Technology in Germany(2015) Koch, SarahThe main target audience of the libraries special collections of East Asian literature is the scholars of humanities and social sciences, just like the sinological libraries are normally considered for the scholars of Chinese Studies. But in recent years one can notice a growing interest in East Asia, especially in China, in the field of science and technology. The increasing international economic relations between China and Germany are raising the demand for engineers who have a broad knowledge of China and the technical developments of both countries. In order to achieve an overview of the rapid technical and scientific developments in China, it is assumed that specialized language skills are required to be able to access important information. As the National Library for all areas of engineering and natural sciences, the German National Library of Science and Technology (TIB) takes the responsibility to provide research and industry with specialist literature and information – nationally and internationally. Therefore the TIB also built up the most comprehensive collection of modern Chinese literature in science and technology in Germany. As to understand how the library can provide a good support for the much more heterogeneous user group of Chinese literature in this field as well, it is necessary to learn more about their requirements. The purpose of this paper is to get an overview of the Chinese research output in science and technology by analyzing international databases, and to examine the target audience of this kind of literature. It is expected that it will not only show the growing awareness and use of Chinese technical and scientific publications by engineers in Germany, but also demonstrate the importance of access to these publications in terms of scholarly exchange for both German and Chinese scholars in Germany.
- ItemEstimating the information gap between textual and visual representations(New York City : Association for Computing Machinery, 2017) Henning, Christian; Ewerth, RalphPhotos, drawings, figures, etc. supplement textual information in various kinds of media, for example, in web news or scientific pub- lications. In this respect, the intended effect of an image can be quite different, e.g., providing additional information, focusing on certain details of surrounding text, or simply being a general il- lustration of a topic. As a consequence, the semantic correlation between information of different modalities can vary noticeably, too. Moreover, cross-modal interrelations are often hard to describe in a precise way. The variety of possible interrelations of textual and graphical information and the question, how they can be de- scribed and automatically estimated have not been addressed yet by previous work. In this paper, we present several contributions to close this gap. First, we introduce two measures to describe cross- modal interrelations: cross-modal mutual information (CMI) and semantic correlation (SC). Second, a novel approach relying on deep learning is suggested to estimate CMI and SC of textual and visual information. Third, three diverse datasets are leveraged to learn an appropriate deep neural network model for the demanding task. The system has been evaluated on a challenging test set and the experimental results demonstrate the feasibility of the approach.
- ItemSCOAP3/SCOAP3-DH – Gold Open Access in High Energy Physics(Amsterdam : IOS Press, 2016) Kutz, AngelikaSCOAP3 is a global partnership which converts high-quality subscription journals in the field of High-Energy Physics to Open Access through redirection of existing subscription funds. Since January 1, 2014 the SCOAP3 Gold Open Access Repository is providing free access to scientific articles in high quality journals in the field of High Energy Physics. This article describes this international pilot which flips the current subscription-based financing of scientific publication to an output-based financing model (fair share). This includes a description of the unique mechanisms of SCOAP3 as well as its governance structure and short view on the national German contributing partners, especially the German universities (SCOAP3-DH).
- ItemBeitragsmodell (arXiv)(Berlin : de Gruyter, 2017) Tobschall, EstherAuch nach 25 Jahren ist der E-Print-Server arXiv noch immer eine bedeutende Plattform für die schnelle Veröffentlichung von Forschungsergebnissen und we-sentliche Informationsquelle für seine Fachgebiete. arXiv ist zentrales Fachrepo-sitorium und gilt als Prototyp des Open-Access-Publizierens. Dennoch hat Erfolg auch immer seinen Preis: Dieser Beitrag stellt die Informationsplattform arXiv vor und beschreibt die Erfahrungen mit einem Geschäftsmodell, das über Mit-gliedsbeiträge eine nachhaltige Finanzierung erreichen will.