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Natural fiber reinforced polymer composites (NFRPC) are conventionally processed in compression molding process to shell-shaped components, which are mostly used in automotive industry. Therefore, natural fibers (NF) and polypropylene (PP) as matrix system are processed to a thermoplastic organic sheet. Organic sheets are heated in a contact heating press to temperatures above melting temperature of the matrix and then transferred to a forming press. In this paper, Acrodur®Power 2750 X (AP) is used as an alternative to PP. This thermoplastic matrix system enables an increase of fiber content to 75 wt.-% in NFRPC. Furthermore, infrared radiation (IR) with adapted wavelength was used as an alternative to conventional contact heating. To improve the heating behavior of NF/AP infrared and heat transfer additives were used. By adding heat transfer additives and using IR heating with adjusted wavelength, both heating time can be reduced from 45 seconds (NF/PP) to 25 seconds (NF/AP) and a contact heating press can omitted.

The Digital Ilse Aichinger List of Literature (dial) lists as many as possible of the published texts of the author Ilse Aichinger (1921–2016) and makes them available via Wikidata.

Ecosystem services (ES), the benefits that humans obtain from nature, are of great importance for human well-being. The challenge of meeting the growing human demands for natural resources while sustaining essential ecosystem functions and resilience requires an in-depth understanding of the complex relationships between ES. These conflicting (‘trade-offs’) or synergistic (‘synergies’) relationships mean that changes in one ES can cause changes in other ES. By synthesizing the growing body of literature on ES relationships, we identified the following four main study objectives: (i) the identification and characterization of co-occurrences of ES, (ii) the identification of drivers that shape ES relationships, (iii) the exploration of biophysical constraints of landscapes and limitations to their multifunctionality, and (iv) the support of environmental planning, management and policy decisions. For each of these objectives we here describe the key concepts, including viewpoints of different disciplines, and highlight the major challenges that need to be addressed. We identified three cross-cutting themes being relevant to all four main types of studies. To help guiding researchers towards more systematic analyses of ES trade-offs and synergies, we conclude with an outlook on suggested future research priorities.

Understanding the relationship and spatial distribution of multiple ecosystem services (ES) in the context of underlying socio-environmental conditions is an essential element of national ecosystem assessments. Here, we use Germany as an example to present a reproducible blueprint approach for mapping and analysing ecosystem service bundles (ESB) and associated socio-environmental gradients. We synthesized spatial indicators of eleven provisioning, regulating and cultural ES in Germany and used the method of self-organizing maps (SOM) to define and map ESBs. Likewise, we collated data from 18 covariates to delineate socio-environmental clusters (SEC). Finally, we used an overlap analysis to characterise the relationship between the spatial configuration of ESBs and co-occurring SECs. We identified and mapped eight types of ESBs that were characterized to varying degrees by provisioning, cultural and regulating/maintenance services. While ESBs dominated by provisioning ES were linked to regions with distinct environmental characteristics, cultural ESBs were associated with areas where environmental and socio-economic gradients had similar importance. Furthermore, spatial stratification of ESBs indicated hot spots where more detailed analysis is needed within national assessments. Our approach can serve as a blueprint for ESB analysis that can be reproduced in other geographical and environmental settings.

Ecological Focus Areas (EFAs) are one of the three new greening measures of the European Common Agricultural Policy (CAP). We used an interdisciplinary and European-scale approach to evaluate ecological effectiveness and farmers‟ perception of the different EFA options. We assessed potential benefits of EFA options for biodiversity using a survey among 88 ecologists from 17 European countries. We further analyzed data on EFA uptake at the EU level and in eight EU Member States, and reviewed socio-economic factors influencing farmers‟ decisions. We then identified possible ways to improve EFAs. Ecologists scored field margins, buffer strips, fallow land, and landscape features as most beneficial whereas farmers mostly implemented „catch crops and green cover‟, nitrogen-fixing crops, and fallow land. Based on the expert inputs and a review of the factors influencing farmers‟ decisions, we suggest that EFA implementation could be improved by a) prioritizing EFA options that promote biodiversity (e.g. reducing the weight or even excluding ineffective options); b) reducing administrative constraints; c) setting stricter management requirements (e.g. limiting agrochemical use); and d) offering further incentives for expanding options like landscape features and buffer strips. We finally propose further improvements at the next CAP reform, to improve ecological effectiveness and cost-effectiveness.

Over the past decades, the EU’s Common Agricultural Policy has been supporting farmers. At the same time, one could observe a sharp decline in farmland-biodiversity.

Which ecosystem services are addressed? Timber production, crop production, crops for bioenergy use, livestock production, water quality regulation, recreation, erosion control, pollination, nitrogen retention, flood regulation

Vorgestellt wird ein Projekt, das Methoden digital gestutzter Corpusanalyse in der Literaturwissenschaft paradigmatisch zu entwickeln sucht. Als Untersuchungsbeispiel wurde das Werk der osterreichischen Autorin Ilse Aichinger (1921-2016) gewahlt. Der primare Fokus der Untersuchung liegt auf der literarischen Reprasentation von Raum. Bisherige Untersuchungen ihres Werks haben erwiesen, dass Aichingers Bezugnahmen auf Orte und Ereignisse in Wien zentrale Bedeutung zukommt (Fassler, 2011). Ziel des Projekts ist es, grundlegende Strukturen in Aichingers Referenzierung auf Orte zu ermitteln und deren Zusammenhang zur historischen Erfahrung herauszuarbeiten, deren Darstellung im Zentrum ihres Werks steht.

Natural levees can be observed worldwide in nearly all river systems characterized by frequent flooding in combination with the transport of suspended bed material. Several parameters and processes have been suggested to explain the formation and the highly variable geometry of natural levees. However, the effect of bedforms migrating in the main-channel has not been amongst the studied parameters and processes. To fill this gap, this study investigates the relationship between bedforms and natural levee formation by flume experiments. Experiments were conducted in a 2 m wide and 30 m long sediment recirculating flume, monitoring the bed level elevation in the main channel by ultrasonic sensors as well as recording the levee development on the floodplain by a camera. The effect of different bed configurations on the developed levees is compared, and discussed, showing that bedforms could enhance levee formation.

In recent ecosystem service studies, historical data have gained importance as basis for analysing temporal trends and for adapted land management strategies; however, the total number of such studies remains small. Contributing to recent efforts, the primary objective of this study was to assess local ecosystem service products historically used in Germany and to link their distribution patterns to environmental gradients and traditional land-use systems. From maps and detailed regional descriptions of regionally distinct historic farmsteads, building materials used and village types we extracted information on ecosystem service products appropriated in 1950 and before. A spatial model was used to test the derived ecosystem service diversity against topo-climatic conditions. Regional service richness was further compared to the type of traditional land-use system (i.e. focus on crops, focus on livestock or mixed systems). We were able to identify hot spots of historical ecosystem service provisioning in Northern and Southern Germany, whereas significantly lower service numbers were recorded in Eastern Germany. The strong spatial differences in the diversity of historical service products could be explained best by (high) precipitation during the vegetation period. Furthermore, traditional livestock keeping, which relied on various fodder sources and fertilisation techniques to improve poor soil quality, and mixed systems mostly co-occurred with higher regional ecosystem service richness. The baseline of historical ecosystem service provisioning analysed here aids our understanding of current land-use patterns in Germany. Furthermore, a change of perception for specific landscape elements became apparent from our analyses. For example, hedges planted to separate livestock and to provide fuel in the past are today appreciated as important elements for biodiversity conservation. Furthermore, our study helps to preserve knowledge about locally sourced ecosystem services thereby increasing the understanding of cultural landscapes which may help to maintain their remnants.

Sub-Saharan Africa has experienced substantial urbanisation and land degradation processes over the past three decades. Using multi-source satellite imagery combined with geographical and demographic data, this study's aims were to analyse the extent of land cover changes (LCC) and identifying major landscape transformation processes (LTP) and their drivers for four West African cities in Mali, Burkina-Faso, Nigeria and Niger. A common classification scheme was used for a visual interpretation of Corona images from the 1960s and an automated classification of Landsat scenes from 1986, 2000/2001 and 2009. Based on a postclassification comparison LCC were summarized and related to the demographic trends of the past 50 years. Map changes were calculated from 1986 to 2009 to depict LTP (urbanisation, crop expansion, deforestation, and land abandonment) for the cities and their respective hinterlands. To investigate the effect of accessibility and infrastructural factors, LTP were related to the distance to roads, surface water and urban areas. From 1960 to 2009 a large-scale urban agglomeration was detected and the proportion of cultivated land in former natural woody savannas surrounding all four cities increased by 35%. The expansion of cropland during the past 30 years seemed to depend greatly on the availability of irrigation water in the semi-arid Sahelian cities (Kano and Niamey), whilst this was not a major driving factor for the cities of the Sudanian zone (Sikasso and Bobo-Dioulasso). Given the likely increase in water scarcity and land suitable for agriculture, ex ante land use planning and monitoring strategies will become increasingly important.

Flow in rivers and on floodplains is complex as it is affected by several interconnected factors such as topography, sediment transport and vegetation characteristics. The resulting processes are explained by the measure “Hartheim” planned for retention purposes at the Upper Rhine river. On the basis of existing formulas and instruments it is demonstrated that a good estimation of the development of the measure is possible. The proposed procedure is a useful tool for estimating morphological developments of restored river sections.

It is clearly recognizable that the 3-phase drive system engineering has reached a relatively mature stage of development (cf. Chaps. 1– 8). The principle of the field orientated control also has largely asserted itself as the most used method in commercial systems. Control applications for AC drives usually feature linear algorithms in spite of the machine itself being characterized by a non-linear process model and of non-linear operating states (limitation of state variables) to master. Control approaches which take into account system nonlinearities from the outset may fare better in a number of circumstances.

From the principles of electrical engineering it is known that the 3-phase quantities of the 3-phase AC machines can be summarized to complex vectors. These vectors can be represented in Cartesian coordinate systems, which are particularly chosen to suitable render the physical relations of the machines. These are the field-orientated coordinate system for the 3-phase AC drive technology or the grid voltage orientated coordinate system for generator systems. The orientation on a certain vector for modelling and design of the feedback control loops is generally called vector orientation.

At the design of drives an energetically optimal operation represents an essential point of view. Losses increase the energy requirement and produce heat which must be dissipated by additional measures and constructive efforts.

Several models for the vertical distribution of the double-averaged (in time and in the plane parallel to the mean bed) longitudinal velocity in the flow region between roughness troughs and roughness tops are suggested. We found that the same model for velocity distribution may be applicable to a range of flow conditions and roughness types, which share some common features. The suggested models for velocity distribution in the near-bed region are: (1) Constant velocity; (2) exponential velocity distribution; and (3) linear velocity distribution. The measured velocity distributions may be approximated by a single model or by a combination of models depending on roughness geometry and flow conditions. The validity of these models for velocity distribution is supported by laboratory data.

A 1D steady-state flow simulation model was developed. A module evaluating the roughness parameters due to the surface roughness of the main channel and floodplains, riparian forests on the floodplains, and the momentum exchange between the main channel and floodplains was introduced into the model. In the module, the roughness parameters were evaluated by the formulas proposed by the DVWK [Hydraulische Methoden zur Erfassung von Rauheiten (1990); Hydraulische Berechnung von Fliesgewassern (1991)] for steady and uniform flow conditions. The model was calibrated with data obtained from three flood events. Roughness parameters of the main channel and floodplains of both sides were identified in the situation before May 1999. The morphological situation changed slightly. Several sensitivity analyses were carried out for the following cases: (a) the morphological situation before May 1999 with the original parameters, (b) the situation of (a) with various parameters to the realistic extent, (c) the situation being so that the floodplain on the German side were imaginarily enlarged up to utmost 90 m with the original vegetation, and (d) the situation of (c) with various parameters to the realistic extent. Many combinations of the roughness parameters due to the bed roughness and density of the vegetation were examined. The results showed that the most significant parameter is the bed roughness of the floodplains, and the next is that of the main channel. A modification of parameters of the riparian vegetation is of minor importance. The model was extended to a 1D unsteady state flow simulation model and applied to two flood data obtained in the reach between Rheinweiler (186.156 km from Lake Constance) and Hartheim (214.244 km) in Germany in 1998 and 1999. Both measured and calculated hydrographs at Hartheim had their peak discharge at the same time, and the discrepancy of the discharge between the measured and calculated hydrographs was less than 10%.

With explosive growth in the number of mobile devices mobile malware is rapidly spreading, making security one of the key issues. Existing solutions, which are mainly based on binary signatures, are not very effective. The main contribution of this paper is a novel methodology to design and implement secure mobile devices by offering a resource-optimized method that combines efficient, light-weight malware detection on the mobile device with high precision detection methods on cloud servers. We focus on the early detection of behavioral patterns of malware families rather than the detection of malware binary signatures. Upon detection of an attack, an alarm is raised and the damage that can be caused by the detected malware type is estimated. Furthermore, the database with behavioral patterns is continuously updated, thus keeping a device resistant to new malware families.

The paper reports on the methodology applied to assess the morphodynamical development of a river reach which is planned to be re-dynamised, according to the “INTERREG IVa - Redynamisation of the Old Rhine” project (2009-2012). The river reach is located at the Upper Rhine parallel to the Grand Canal d’Alsace. Most of the discharge is directed through the canal and only a minimum discharge is flowing through the River Rhine. In the ca. 40 km long section morphological features are nowadays absent due to limited sediment supply and transport. A dynamic river bed shall be supported by means of floodplain lowering, sediment deposition and removement of bank protection. The applied methodology combines 3D-numerical modelling of the flow field and stability approaches to assess morphological changes with particular reference to the sediment dynamics and stability of the main channel and the floodplain areas.

In Wireless Mesh Networks (WMNs), Network-Wide Broadcasts (NWBs) are a fundamental operation, required by routing and other mechanisms that distribute information to all nodes in the network. However, due to the characteristics of wireless communication, NWBs are generally problematic. Optimizing them thus is a prime target when improving the overall performance and dependability of WMNs. Most existing optimizations neglect the real nature of WMNs and are based on simple graph models, which provide optimistic assumptions of NWB dissemination. On the other hand, models that fully consider the complex propagation characteristics of NWBs quickly become unsolvable due to their complexity. In this paper, we present the Monte Carlo method Probabilistic Breadth-First Search (PBFS) to approximate the reachability of NWB protocols. PBFS simulates individual NWBs on graphs with probabilistic edge weights, which reflect link qualities of individual wireless links in the WMN, and estimates reachability over a configurable number of simulated runs. This approach is not only more efficient than existing ones, but further provides additional information, such as the distribution of path lengths. Furthermore, it is easily extensible to NWB schemes other than flooding. The applicability of PBFS is validated both theoretically and empirically, in the latter by comparing reachability as calculated by PBFS and measured in a real-world WMN. Validation shows that PBFS quickly converges to the theoretically correct value and approximates the behavior of real-life testbeds very well. The feasibility of PBFS to support research on NWB optimizations or higher level protocols that employ NWBs is demonstrated in two use cases.

In service networks, discovery plays a crucial role as a layer where providers can be published and enumerated. This work focuses on the responsiveness of the discovery layer, the probability to operate successfully within a deadline, even in the presence of faults. It proposes a hierarchy of stochastic models for decentralized discovery and uses it to describe the discovery of a single service using three popular protocols. A methodology to use the model hierarchy in wireless mesh networks is introduced. Given a pair requester and provider, a discovery protocol and a deadline, it generates specific model instances and calculates responsiveness. Furthermore, this paper introduces a new metric, the expected responsiveness distance d er , to estimate the maximum distance from a provider where requesters can still discover it with a required responsiveness. Using monitoring data from the DES testbed at Freie Universitat Berlin, it is shown how responsiveness and d er of the protocols change depending on the position of nodes and the link qualities in the network.