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101.
Energy efficient reliable communication over an unpredictable wireless medium is a major challenge for resource constrained wireless sensor nodes in process/environment control application. In this paper, we propose a Soft Decision Decoding (SDD) based advanced Forward Error Correction (FEC) scheme for low power distributed sensor nodes. The proposed BCH (Bose-Chaudhuri-Hocquenghem) based adaptive Chase-2 decoding scheme offers attractive energy benefits as compared to Hard Decision Decoding (HDD). The reduced decoding complexity is obtained by limiting the codeword search space and fewer algebraic operations compared to standard Chase-2. A realistic environmental scenario incorporating path loss, Rayleigh fading and Additive White Gaussian Noise has been considered to investigate the performance of the proposed scheme. A detailed comparison is carried out with HDD of BCH codes using the widely known Crossbow MicaZ node parameters. The simulation results indicate that for low power WSN, the proposed SDD based adaptive scheme offers better tradeoff between energy and reliability than HDD schemes. 相似文献
102.
In this paper we analyze the effect of European and national funding on innovation input and output at the firm level. In terms of innovation input, we do not find evidence that one policy crowds out the effect of the other. Instead, the policies are complements. In terms of output, we find that subsidy recipients are more active with respect to patenting. A citation analysis of patents reveals that the subsidy recipients file patents that are more valuable (in terms of forward citations) than those filed in the counterfactual situation of receiving no public support. These results suggest that public funding triggers socially beneficial research projects and that the co-existence of national and European policies does not lead to crowding-out effects when compared to a hypothetical world of a closed economy with no supplemental European policies. 相似文献
103.
Prof. Dr. Andreas Fink Prof. Dr. Natalia Kliewer Prof. Dr. Dirk Mattfeld Prof. Dr. Lars Mönch Prof. Dr. Franz Rothlauf Prof. Dr. Guido Schryen Prof. Dr. Leena Suhl Prof. Dr. Stefan Voß 《WIRTSCHAFTSINFORMATIK》2014,56(1):21-29
In this paper, we sketch some of the challenges that should be addressed in future research efforts for model-based decision support in manufacturing and service networks. This includes integration issues, taking into account the autonomy of the decision-making entities in face of information asymmetry, the modeling of preferences of the decision-makers, efficiently determining robust solutions, i.e. solutions that are insensitive with respect to changes in the problem data, and a reduction of the time needed for model building and usage. The problem solution cycle includes problem analysis, the design of appropriate algorithms and their performance assessment. We are interested in a prototypical integration of the proposed methods within application systems, which can be followed up with field tests of the extended application systems. We argue that the described research agenda requires the interdisciplinary collaboration of business and information systems engineering researchers with colleagues from management science, computer science, and operations research. In addition, we present some exemplifying, illustrative examples of relevant research results. 相似文献
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105.
Take care of your belongings today – securing accessibility to complex electronic business processes
Klaus Rechert Dirk von Suchodoletz Isgandar Valizada Johann Latocha Tatiana Jimenez Cardenas Alibek Kulzhabayev 《Electronic Markets》2014,24(2):125-134
Most of today’s business processes are based solely on digital data. Input, output, and intermediate results are pure digital objects. Keeping such data accessible and meaningful but even more importantly keeping the business processes functional is challenging. With regards to complex electronic business processes traditional archiving does not provide satisfactory results. Due to the fast technical life-cycle the time gap between archiving and re-enactment or reuse of a process poses risks and increases the uncertainty on achievable results. We propose a novel strategy bridging this specific time gap. For this we present a scalable and cost-effective infrastructure with associated workflows focusing on a process’ execution context. Most importantly the process’ developers are able to assess the preserved results in a timely manner, and thus, reduce the uncertainty on future re-enactment results. 相似文献
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AESOP’s 2009 Congress was hosted by the University of Liverpool as part of the centenary celebration of its Department of Civic Design, the world’s oldest university planning school. ‘Why Can’t the Future be More Like the Past?’ was the conference title on all the banners and conference bags – an oddly querulous question, nevertheless it did the trick in getting participants to think historically throughout AESOP 2009. Michael Hebbert and Dirk Schubert ran a planning history track for six of the conference’s seven parallel session slots. Their call for papers elicited 30 abstracts which reduced to 17 papers, a comfortable quantity allowing good time for presentation and discussion. The track had the fortune to be allocated a wood‐panelled Architecture lecture theatre with superb projection facilities – more than one speaker gasped at the glory of their own PowerPoint images. 相似文献
109.
In project teams that are distributed across the international subsidiaries of a firm, collaboration can be a challenge. The organizational context of projects is not always conducive to international collaboration. Priorities and interests of sub-teams are likely to differ from those of the central team. In a grounded theory study of international client projects in a project-based organization, the impact of organizational context on collaboration is explored. It was found that the organizational context can provide important resources such as authority, policies, procedures and systems that can be appropriated to enable collaboration. However, this applies only when there are drivers for collaboration, consisting of interdependency and interest in the project's success. Even in a context not conducive to collaboration, the drivers encourage teams to constitute informal mechanisms, enabling some level of collaboration. A framework for the impact of organizational context on collaboration in international projects is presented. 相似文献
110.
The role of conductive pathways in the conductivity and rheological behavior of poly(methyl methacrylate)–graphite composites
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Up to now, research on the dynamic process of conductive network formation has tended to focus on composite particles with one‐dimensional geometry, such as carbon black and carbon nanotubes. However, studies on this subject based on fillers with two‐dimensional structure, such as graphite, are rare in the literature. In this work, the dynamic percolation and rheological properties of poly(methyl methacrylate) (PMMA)–graphite composites under an electric field were investigated. The activation energies of conductive network formation and polymer matrix mobility were calculated from the temperature dependence of the percolation time and the zero‐shear viscosity. It was found that the activation energy calculated from the zero‐shear viscosity was not influenced by the electric field in the concentration range investigated, but the electric field had an effect on the activation energy calculated from the percolation time. This finding emphasizes that the electrical and rheological properties have different physical origins. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43810. 相似文献