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991.
Wireless Personal Communications - Radio frequency identification (RFID) is a promising and widespread wireless communication technology for entity identification or authentication. By the emerging...  相似文献   
992.
Neurorobotics     
The field of neurorobotics encompasses the intersection of computational neuroscience and robotics. The TUM-led neurorobotics subproject of the Human Brain Project is actively researching concepts within the field and developing the tools to allow researchers to fully explore simulated robotics driven by computational neuroscience models. Further, the development of biologically inspired, tendon-driven robotics systems provides a unique research platform. These efforts allow researchers to explore the interesting space from computational neuroscience to intelligent robots and back.  相似文献   
993.
In wireless sensor networks, the sensor nodes find the route towards the sink to transmit data. Data transmission happens either directly to the sink node or through the intermediate nodes. As the sensor node has limited energy, it is very important to develop efficient routing technique to prolong network life time. In this paper we proposed rendezvous-based routing protocol, which creates a rendezvous region in the middle of the network and constructs a tree within that region. There are two different modes of data transmission in the proposed protocol. In Method 1, the tree is directed towards the sink and the source node transmits the data to the sink via this tree, whereas in Method 2, the sink transmits its location to the tree, and the source node gets the sink’s location from the tree and transmits the data directly to the sink. The proposed protocol is validated through experiment and compared with the existing protocols using some metrics such as packet delivery ratio, energy consumption, end-to-end latency, network life time.  相似文献   
994.
The kinetics of reaction between HCl gas and terpenes (α-pinene, myrcene, camphene, Δ3-carene) and isoamylene (2-methyl-2-butene) were studied,The reactions of HCl with α-pinene and Δ3-carene were found to be zero order with respect to HCl and second order with respect to the olefin. TThe reactions between HCl and myrcene (in the presence of CuCl as a catalyst) and camphene were found to be first order with respect to HCl as well asThe absorption of HCl in 2-methyl-2-butene was found to be second order with respect to HCl and first order with respect to 2-methyl-2-butene. The valu  相似文献   
995.
The concept of tailored interfaces has been applied to the synthesis of nanoscale α-Al2O3. Tween-80 (poly-oxyethylene(20) sorbitan monooleate, T-80) was used as a surface modifier in the sol–gel process for this purpose. High-resolution transmission electron microscopy study of the powder obtained with T-80 confirmed the particle size of α-Al2O3 (∼55 nm) and morphology (spherical). The exothermic peak temperature in the differential thermal analysis was shifted to a lower temperature (∼917°C) when the powder was derived from a T-80 modifier content of 10 wt%. X-ray diffraction showed that the α-Al2O3 phase was the major phase that existed in modifier-derived powder that was sintered at 1000°C. The experiments, based on linear shrinkage, indicated that the powder with T-80 (10 wt%) could be densified at a low temperature.  相似文献   
996.
Long hair-like fibres were injected at the boundary and centreline of a turbulent pipe flow of water and polymeric solution. Pressure drop and mean velocity profiles were measured at various Reynolds numbers and injection rates in order to study some mechanistic aspects of drag reduction in these additive systems. Drag reduction in a fibre-water system is attributed to a decrease in the momentum transfer in the turbulent-core region, whereas synergism has been found to be a wall phenomenon.  相似文献   
997.
The analysis presented is for laminar film boiling on a vertical surface treating the test section as a fin with the heat leakage from its ends. The formulation of the problem is accomplished as a conjugate between the thermal conduction in the test section and the phenomenon of film boiling on its lateral face. This approach revealed that the film boiling heat transfer coefficients, both local and average values, are profoundly influenced by the fin parameter. An explicit form of the equation is provided from the computer results to evaluate the film boiling heat transfer coefficient.  相似文献   
998.
The catalytic oxidation of volatile organic compounds (VOCs) into mainly CO2 and H2O appears promising in the context of the abatement of atmospheric gaseous pollutants and is the subject of this paper. The catalytic oxidation of toluene and m-xylene was carried out in a tubular reactor on a phenolic resin based activated carbon fiber (ACF) impregnated with nitrates of Co, Cr, Ni, and Cu at the reaction temperatures below 300 °C. The extent of the removal (i.e. conversion) of toluene and m-xylene was examined through the breakthrough curves and was found to strongly depend on the types and loading of the metal precursors. The experimental results showed that the reaction rate was significantly affected by O2 concentration below 3% (v/v). The performance of the ACFs impregnated with 5% (w/w) of Ni oxide was found to be superior to that of other metal oxides at reaction temperature between 170 and 290 °C. A surface kinetic mechanism for the catalytic oxidation of volatile organic compound was proposed and incorporated in a transport model developed to explain the experimental breakthrough data.  相似文献   
999.
1000.
Conductivity of molten Mg(NO3)2. 6H2O + NH4NO3 system containing up to 80 mole percent of the latter was measured in the temperature range 320–400 K. Temperature dependence of conductivity exhibited Arrhenian behaviour. Conductivity—composition isotherms were non-linear indicating weak ordering tendencies. Equivalent conductivity data did not obey Markov equation; deviations have been interpreted in terms of the Tobolsky parameter (θ). Constancy of θ indicate that the water of hydration in the system remains with Mg2+ ions and is unaffected by the addition of NH+4 ions.  相似文献   
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