71 research outputs found

    HARMLESS: Cost-Effective Transitioning to SDN

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    Recently, Software-Defined Networking has grown out of being an "intriguing approach" and turned into a "must-have" for communication networks to overcome many long-standing problems of traditional networking. However, there are still some obstacles on the way to the widespread adoption. Current commodity-off-the-shelf (COTS) SDN offerings are still in their infancy and are notorious for lacking standards compliance, scalability, and unpredictable performance indicators compared to their legacy counterparts. On the other hand, recent software-based solutions might mitigate these shortcomings, but in terms of cost-efficiency and port density they are in a lower league. Here, we present HARMLESS, a novel SDN switch design that combines the rapid innovation and upgrade cycles of software switches with the port density of hardware-based appliances into a fully data plane-transparent, vendor-neutral and cost-effective solution for smaller enterprises to gain a foothold in this era. The demo showcases the SDN migration of a dumb legacy Ethernet switch to a powerful, fully reconfigurable, OpenFlow-enabled network device without incurring any major performance and latency penalty, nor any substantial price tag enabling to realize many use cases that would have otherwise needed standalone hardware appliances

    Az on-line vásárlás vevői elfogadottsága Magyarországon (Adoption of on-line commerce in Hungary)

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    A hazai internethasználat terjedésével egyre népszerűbbek az on-line kereskedelmi modellek, egyre több cég kísérli meg, hogy terméket vagy szolgáltatást értékesítsen az interneten. Például az on-line könyvértékesítések és a diszkont légitársaságok jegyeladásai az e-kereskedelem kiugró ágazatai közé tartoznak – ez a hasonlóság adja a tanulmány alapját. Dinamikusan növekvő keresleti igények honorálják az internetes megjelenést, és fordítva: a fogyasztói e-felkészültséget gyakran a kínálati oldal indukálja. A szerzők kutatásukban a hazai internethasználat bemutatásával és fókuszcsoportos beszélgetések révén próbálják meg feltárni, hogy mi minden szükséges ahhoz, hogy valódi alternatívát jelentsen az on-line kereskedelem a vevők számára. Kísérletet tesznek a keresleti oldal átfogó bemutatására, hasonlóságokra és különbségekre fókuszálva, valamint szintén összevetik a kínálati oldal jellemző karaktereit, ezek egyezőségeit és eltéréseit vizsgálva. ______________ With the spreading of Hungarian internet usage online e-commerce models have become more and more popular, more and more companies start to sell products and services via the internet. For instance the on-line book sales and purchase of discount airline tickets belong to the leading branches of e-business and demonstrate that dynamically increasing demand generates supply. In this research first the authors introduces the basic data about internet usage in Hungary. Then, based on a series of focused group discussions they examine what the key customer requirements are to really consider e-commerce as a serious alternative for traditional shopping. They attempt to describe the demand side and juxtapose it with the characteristics of the supply side of Hungarian e-commerce

    The correlation theory of the chemical bond

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    The quantum mechanical description of the chemical bond is generally given in terms of delocalized bonding orbitals, or, alternatively, in terms of correlations of occupations of localised orbitals. However, in the latter case, multiorbital correlations were treated only in terms of two-orbital correlations, although the structure of multiorbital correlations is far richer; and, in the case of bonds established by more than two electrons, multiorbital correlations represent a more natural point of view. Here, for the first time, we introduce the true multiorbital correlation theory, consisting of a framework for handling the structure of multiorbital correlations, a toolbox of true multiorbital correlation measures, and the formulation of the multiorbital correlation clustering, together with an algorithm for obtaining that. These make it possible to characterise quantitatively, how well a bonding picture describes the chemical system. As proof of concept, we apply the theory for the investigation of the bond structures of several molecules. We show that the non-existence of well-defined multiorbital correlation clustering provides a reason for debated bonding picture

    T-Cell Subsets in Rheumatoid Arthritis Patients on Long-Term Anti-TNF or IL-6 Receptor Blocker Therapy

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    Data on the impact of biological therapies on the T-cell phenotype in rheumatoid arthritis are limited. Here, we prospectively measured the percentages of 15 circulating T-cell subtypes using flow cytometry. We obtained transversal and longitudinal data in 30 anti-TNF responders, 19 secondary anti-TNF nonresponders, and 43 IL-6R antagonist responders, before, 8 weeks and at least 6 months after biological therapy. Untreated RA patients and healthy controls were also included. The important findings are the following: ( 1) the proportion of regulatory T-cells (Tregs) which are decreased in untreated RA patients becomes normal in all long-term-treated groups; ( 2) in anti-TNF responders as well as in nonresponders, the frequencies of naive CD4+ and CD8+ cells are lower, whereas those of proinflammatory Th1, Th2, and Th17 cells and HLA-DR+-activated cells are higher than those in untreated RA or healthy controls; ( 3) in IL-6R responders, Th1 proportion is decreased, while that of Th2 and Th17 is increased as compared to that in anti-TNF-treated patients and controls; ( 4) pending confirmation, a CD4CD69 ratio <2.43 at baseline, could be useful to predict a good therapeutic response to anti-TNF therapy. This study provides comprehensive information regarding the long-term impacts of those biological therapies on the ecotaxis of T-cells in RA

    Quantum information-based analysis of electron-deficient bonds

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    Recently, the correlation theory of the chemical bond was developed, which applies concepts of quantum information theory for the characterization of chemical bonds, based on the multiorbital correlations within the molecule. Here for the first time, we extend the use of this mathematical toolbox for the description of electron-deficient bonds. We start by verifying the theory on the textbook example of a molecule with three-center two-electron bonds, namely the diborane(6). We then show that the correlation theory of the chemical bond is able to properly describe bonding situation in more exotic molecules which have been synthetized and characterized only recently, in particular the diborane molecule with four hydrogen atoms [diborane(4)] and neutral zerovalent s-block beryllium complex, whose surprising stability was attributed to a strong three-center two-electron π\pi bond stretching across the C-Be-C core. Our approach is of a high importance especially in the light of a constant chase after novel compounds with extraordinary properties where the bonding is expected to be unusual
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