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101.
LAN emulation on an ATM network 总被引:1,自引:0,他引:1
Hong Linh Truong Ellington W.W. Jr. Le Boudec J.Y. Meier A.X. Pace J.W. 《Communications Magazine, IEEE》1995,33(5):70-85
The authors evaluate architecture alternatives relating to the provision of a LAN emulation service over a connection-oriented ATM network, and present the LAN emulation architecture as actually adopted by the ATM Forum LANE SWG. The role of servers is discussed as is the provision of broadcast/multicast services 相似文献
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104.
Felix Bob Wijaya Abhishek Ray Mohapatra Shahrokh Sepehrirahnama Kian-Meng Lim 《Microfluidics and nanofluidics》2016,20(5):69
Under the influence of acoustic radiation force, particles can be trapped and deformed at the pressure node in a microfluidic channel. Based on this principle, the elastic modulus of biological cells can be estimated. In this study, a numerical framework, consisting of a boundary element model for acoustic field and an axisymmetric shell model, is developed to simulate the cell deformation under acoustic radiation force. The boundary element model is used to calculate the radiation traction exerted on the cell surface. The cell membrane deformation due to this traction is simulated by using the axisymmetric shell model. The Young’s moduli of algae and red blood cell membranes are then estimated by comparing the experimental observation with the simulated membrane deformation. It is found that the value of Young’s modulus of the red blood cell membrane is lower than that of algae cell membrane. Furthermore, for both cells, the estimated Young’s moduli are negligible compared to the bulk moduli of the cells reported in the previous studies. 相似文献
105.
Patrick Afflerbach Gregor Kastner Dr. Felix Krause Prof. Dr. Maximilian Röglinger 《WIRTSCHAFTSINFORMATIK》2014,56(4):223-236
Promising to cope with increasing demand variety and uncertainty, flexibility in general and process flexibility in particular are becoming ever more desired corporate capabilities. During the last years, the business process management and the production/operations management communities have proposed numerous approaches that investigate how to valuate and determine an appropriate level of process flexibility. Most of these approaches are very restrictive regarding their application domain, neglect characteristics of the involved processes and outputs other than demand and capacity, and do not conduct a thorough economic analysis of process flexibility. Against this backdrop, the authors propose an optimization model that determines an appropriate level of process flexibility in line with the principles of value-based business process management. The model includes demand uncertainty, variability, criticality, and similarity as process characteristics. The paper also reports on the insights gained from applying the optimization model to the coverage switching processes of an insurance broker pool company. 相似文献
106.
Łukasz Ciupiński Grzegorz Krzesiński Krzysztof Kurzydłowski Piotr Marek Tomasz Zagrajek Victor Bykov Paweł Czarkowski Wolfgang Daenner Andrzej Dudek Felix Schauer 《Fusion Engineering and Design》2009,84(2-6):613-617
The stellarator Wendelstein 7-X is under construction at the Max-Planck-Institut für Plasmaphysik in Greifswald. Its superconducting coil system is fixed by a massive structure. During machine operation the coils exert high forces and moments against each other and the central support structure (CSS). Therefore, the detailed analysis of the coil to CSS connections, the so-called central support elements (CSE), is a critical item. The major details of the design have been frozen; nevertheless, there is still need for detailed analysis of the CSEs due to assembly issues, and later on for exploring operational limits of the machine. These analyses have to be performed quickly, reliably, and shall provide results in a standardized form to enable timely responses to the assembly team. Special numerical tools – finite element (FE) parametric models of CSEs – have been developed for the purpose of such analyses. In the models, the geometry, material properties, contact conditions, loads as well as results presentation are defined in a parametric way. The use of the developed models for the definition of the final weld parameters, bolt preloads, assessment of acceptable tolerances, and optimal positions of the CSE-wedges before welding is also discussed. 相似文献
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A new concept for the enrichment of lithium minerals is offering higher purity and higher yield by applying new processing technologies addressing the specific properties of the pegmatitic host rock. Additional value is created from high quality by-products which will improve the sustainability of mining activity and the overall cost base. Within the new concept, flotation may even be avoided where wet separation techniques are not applicable.Two innovative processing technologies have been integrated in the new concept: electrodynamic fragmentation and optical sorting. Detailed results of lab-technical tests show that the new process design can achieve highly selective liberation and separation processes. Optical and mineralogical analyses of the test products indicate a high benefit for commercial applications. 相似文献
109.
Recently it was proposed, that the hampered formation of external protective chromia scales on FeCr‐alloys in water vapour containing, low‐pO2 gases is correlated with enhanced internal oxidation of chromium. In the present study the internal oxidation kinetics of Fe? 10Cr (in mass%) during isothermal oxidation in Ar? H2? H2O mixtures at temperatures in the range 800–1050 °C has been investigated. It was found that the tendency for Cr to become internally oxidized decreased with decreasing temperature. At the higher test temperatures the internal oxide precipitates consisted of Fe/Cr‐spinel. With decreasing temperature the precipitates near the oxidation front gradually exhibited increasing amounts of chromia. At 900 °C the oxidation morphology in the Ar? H2 base gas mixture changed from exclusive internal oxidation of Cr at a water vapour content of 2% towards a combined internal Cr oxidation and external Fe‐oxide formation at higher water vapour partial pressures. 相似文献
110.
Dr. Saskia Wolf Dr. Svenja Warnecke Jörg Ehrit Dr. Friedrich Freiberger Prof. Dr. Rita Gerardy‐Schahn Prof. Dr. Chris Meier 《Chembiochem : a European journal of chemical biology》2012,13(17):2605-2615
The cycloSal approach has been used in the past for the synthesis of a range of phosphorylated bioconjugates. In those reports, cycloSal nucleotides were allowed to react with different phosphate nucleophiles. With glycopyranosyl phosphates as nucleophiles, diphosphate‐linked sugar nucleotides were formed. Here, cycloSal‐nucleotides were used to prepare monophosphate‐linked sugar nucleotides successfully in high anomeric purity and high chemical yield. The method was successfully used for the synthesis of three nucleotide glycopyranoses as model compounds. The method was then applied to the syntheses of CMP‐N‐acetyl‐neuraminic acids (CMP‐Neu5NAc) and of four derivatives with different modifications at their amino functions (N‐propanoyl, N‐butanoyl, N‐pentanoyl and N‐cyclopropylcarbonyl). The compounds were used for initial enzymatic studies with a bacterial polysialyltransferase (polyST). Surprisingly, the enzyme showed marked differences in terms of utilisation of the four derivatives. The N‐propanoyl, N‐butanoyl, and N‐pentanoyl derivatives were efficiently used in a first transfer with a fluorescently labelled trisialo‐acceptor. However, elongation of the resulting tetrasialo‐acceptors worsened progressively with the size of the N‐acyl chain. The N‐pentanoyl derivative allowed a single transfer, leading to a capped tetramer. The N‐cyclopropylcarbonyl derivative was not transferred. 相似文献