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31.
Karl Sauer Diemair E. Dinslage Kanitz Schwaibold Willy Lindner Haevecker Lehnartz E. Becker W. Schreiber Werner Hofmann Eduard Hofmann Steinbeck H. Süllmann Griebel Rudolf Abderhalden Lars Erlandsen Heyns O. v. Soden C. Steinhoff J. Großfeld Frey-Wyssling W. Sutthoff Bäurle Willy Lindner Ed. Rentz Bandow Gerards K. N. v. Kaulla O. v. Soden Maria Cicconi Pawletta Baars R. Grau Lerche Beckel O. Windhausen Felicitas Rolleri Jesser Karl Boresch R. W. Seuffert K. Müller Schloemer K. Höll Johannes Wolf Brüning Patzsch W. Ludorff 《European Food Research and Technology》1941,81(3):223-288
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Robert Lemanis Kian Tadayon Elke Reich Gargi Joshi Richard Johannes Best Kevin Stevens Igor Zlotnikov 《Journal of the Royal Society Interface》2022,19(191)
The ability of evolution to shape organic form involves the interactions of multiple systems of constraints, including fabrication, phylogeny and function. The tendency to place function above everything else has characterized some of the historical biological literature as a series of ‘Just-So’ stories that provided untested explanations for individual features of an organism. A similar tendency occurs in biomaterials research, where features for which a mechanical function can be postulated are treated as an adaptation. Moreover, functional adaptation of an entire structure is often discussed based on the local characterization of specimens kept in conditions that are far from those in which they evolved. In this work, environmental- and frequency-dependent mechanical characterization of the shells of two cephalopods, Nautilus pompilius and Argonauta argo, is used to demonstrate the importance of multi-scale environmentally controlled characterization of biogenic materials. We uncover two mechanistically independent strategies to achieve deformable, stiff, strong and tough highly mineralized structures. These results are then used to critique interpretations of adaptation in the literature. By integrating the hierarchical nature of biological structures and the environment in which they exist, biomaterials testing can be a powerful tool for generating functional hypotheses that should be informed by how these structures are fabricated and their evolutionary history. 相似文献
33.
Daniel Schreckling Johannes Köstler Matthias Schaff 《Information Security Technical Report》2013,17(3):71-80
We introduce Kynoid, a real-time monitoring and enforcement framework for Android. Kynoid is based on user-defined security policies which are defined for data-items. This allows users to define temporal, spatial, and destination constraints which have to hold for single items. We introduce an innovative approach to allow for the real-time tracking and enforcement of such policies. In this way, Kynoid is the first extension for Android which enables the enforcement of security policies of data-items stored in shared resources. We outline Kynoid's architecture, present its operation and discuss it in terms of applicability, and performance. By providing a proof-of-concept implementation we further show the feasibility of our framework. 相似文献
34.
Carolin Kaiser Johannes Kröckel Freimut Bodendorf 《Information Systems and E-Business Management》2013,11(4):597-621
An increasing number of people are joining online social networks. By interacting with each other, network members influence one another’s opinion. These influencing effects can be utilized by marketing. A wave of influence can be triggered by addressing only a few opinion leaders in the network. Targeting the right opinion leaders is a big challenge. This paper presents a new approach which simulates the spread of opinions when influencing certain opinion leaders. In contrast to other approaches, the influencing effects are not assumed but revealed by real data. The principles of opinion formation are detected by ant mining algorithms before they are applied to simulate the spread of opinions. The approach is applied to an online gaming community and provides valuable insights for marketing. 相似文献
35.
The present paper deals with the computational simulation of a pile of thin sheets. The sheets are not laminated or glued, but they interact by frictional contact. In general, it is not possible to perform a full-scale finite element contact computation for piles containing thousands of sheets; the problem size becomes too large, and numerical solution methods suffer from severe convergence problems due to the large number of strongly coupled contact conditions. In this paper, a macroscopic material model is presented for the two-dimensional case. The pile of sheets is homogenized by introducing an effective anisotropic constitutive law, which is motivated by formulations of the theory of elasto-plasticity. This macroscopic material law models the behavior of a pile of sheets, allowing for no tensile stresses in the direction normal to the sheets and obeying Coulomb??s law of friction in the tangential contact plane. Applying this macroscopic material model, an equivalent homogeneous body can be treated using much coarser discretizations. Computational results for the problems are provided, and a comparison with simplified contact computations is done. 相似文献
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Composite materials with vibrations damping qualities can be made of two steel sheets enclosing a viscoelastic plasticcorelayer. These sandwich sheets often need to be formed. Material parameters are determined to describe the forming process. Based on these parameters, pilot studies are carried out in order to develop recommendations for forming this class of material. 相似文献
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