摘要:
A source node estimates not only the schedule time offset of the destination node but also the clock drift of the destination node. In this way, the source node may choose very accurately the transmission start time of an information packet to this destination node so that typically only one very short preamble needs to be transmitted. The estimation of time offset and clock drift between two nodes is achieved through tone or more previous transmissions between these two nodes, in particular, information relating to these parameters is transmitted from the destination node to the source node in reply to a preamble transmitted by the source node to the destination node.
摘要:
A solid oxide fuel cell is provided. The solid oxide fuel cell includes a cathode, at least an electrolyte membrane, and an anode having a ceramic material and an alloy of nickel and at least a second metal, selected from aluminum, titanium, molybdenum, cobalt, iron, chromium, copper, silicon, tungsten and niobium, the alloy having an average particle size not higher than 20 nm. The provided solid oxide fuel cells shows enduring efficiency when fuelled with different fuels, including hydrogen and hydrocarbons, in a wide range of operating temperatures.
摘要:
The radiation characteristics of an antenna are made configurable including in the antenna a plurality of radiating elements and associating to each of said radiating elements a respective chain for processing the signal in transmission and/or reception with a module for weighting digital signals capable of applying to a digital signal at least a respective weighting coefficient and an antenna conversion set interposed between the module for weighting digital signals and one of the radiating elements of the antenna. The antenna conversion set operates on a digital signal on the side of the signal weighting module and on an analogue signal distributed on the processing chains associated to each radiating element of the antenna propagates (in transmission and/or reception), while respective weight coefficients are applied to said digital signal weighting modules. The weighting coefficients determine the radiation diagram of the antenna.
摘要:
A fuel cell having a membrane-electrode assembly including an anode, a cathode, and a polymer electrolyte membrane interposed between the anode and the cathode, wherein the polymer electrolyte membrane is a sulfonated polysulfone polymer.
摘要:
A wireless transceiver station including an antenna device and a casing, the antenna device including at least one resonator element cooperating with the casing of the wireless transceiver station and having a shape with a low aspect ratio so as to be conformal with the casing, the at least one resonator element including a composite material and being adapted to be excited by a feed system which is positioned inside the resonator element so as to allow the antenna device to irradiate with a substantially omnidirectional radiation pattern.
摘要:
A method for making a sound-insulating load-bearing floor, includes the following steps: providing a load-bearing floor; applying a sound-insulating material onto the load-bearing floor so as to form a substantially continuous coating layer; allowing the substantially continuous coating layer to dry; wherein the sound-insulating material includes: 40% by weight to 95% by weight, preferably 60% by weight to 90% by weight, with respect to the total weight of the sound-insulating material, of at least one rubber in a subdivided form; 5% by weight to 60% by weight, preferably 10% by weight to 40% by weight, with respect to the total weight of the sound-insulating material, of at least one binding agent including at least one water-dispersible polymer having a glass transition temperature (Tg) of −50° C. to +50° C., preferably of −40° C. to +10° C.
摘要:
A connector for optical fiber is described. The connector has a main body having a first fiber supporting element for supporting, within a fiber supporting seat, a first portion of at least one optical fiber and leaving an end portion of the at least one optical fiber project from the main body. The connector further has a second fiber supporting element for supporting the end potion of the at least one optical fiber. The second fiber supporting element is slidably associated with the main body and mobile between a first operational position wherein the end portion of the at least one optical fiber is supported by the second fiber supporting element and a second operational position wherein at least an end part of said end portion projects from said connector. The main body comprises a seat for hosting the second fiber supporting element when the second fiber supporting element is moved from the first operational position to the second operational position. The seat is located below the fiber supporting seat of the first fiber supporting element.
摘要:
An optical device includes an optical splitter having an input port, a first output port, a second output port and a resonant structure including at least a resonator, the optical splitter being adapted to receive at the input port a WDM optical signal and to output at the first and second output ports, respectively, a first and a second portion of the optical signal, the second portion including the channels lying on a sub-grid of optical frequencies spaced by an integer multiple of the WDM frequency spacing; an optical combiner having a first input port, a second input port, an output port and adapted to receive at the first and second input ports, respectively, the first and the second portions and adapted to output them at said output port; a first optical path optically connecting the first output port of the optical splitter to the first input port of the optical combiner so as to propagate the first portion; a second optical path optically connecting the second output port of the optical splitter to the second input port of the optical combiner so as to propagate the second portion; and an optical filter optically coupled to the second optical path, wherein the optical combiner includes at least one resonant structure including at least a resonator.