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61.
The main concern of the present publication is the computation of dynamic loads of wind turbine power trains, with particular emphasis on planetary gearbox loads. The applied mathematical approach relies on a non‐linear finite element method, which is extended by multi‐body system functionalities, and aerodynamics based on the blade element momentum theory. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
62.
Group-orthogonal multi-carrier code division multiple access (GO-MC-CDMA) has recently been proposed as a promising technique for the uplink segment of wireless systems. In this paper we propose and analyze a related scheme, group-orthogonal multi-carrier code division multiplexing (GO-MC-CDM), suitable for the downlink segment of the future generation of wireless systems. The proposed system is shown to offer a similar bit error rate (BER) performance as the downlink version of GO-MC-CDMA at a fraction of its computational complexity. An analytical expression for the BER when using maximum likelihood (ML) detection is derived providing valuable insight into the parameters affecting the system performance and providing a basis for its optimization. Simulation results using parameters and (correlated) channel models aiming at the next generation of wireless systems are provided confirming the analytically derived results. 相似文献
63.
64.
A new scheme to alleviate contention in optical burst switching networks is proposed. It consists of preventively reserving resources in a node, to be used if resources are busy on the next hop node. The burst is sent back to the preceding node and then resent forward. Simulations are carried out to assess the feasibility of the proposed scheme. Its performance is compared with that of contention resolution based on deflection routing. 相似文献
65.
Quartz Films: Water‐Induced Phase Separation Forming Macrostructured Epitaxial Quartz Films on Silicon (Adv. Funct. Mater. 35/2014)
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66.
New ways of achieving small, multiband, multifunctional, and standard solutions for mobile handset antennas are demanded in the current wireless market. A non‐resonant element of , a matching network, and a slotted ground plane are proposed to satisfy mobile market demands that require multiband operation and small antenna solutions. The main advantage of the proposed design is that with only one non‐resonant element of considerably small size (0.015λ, 900 MHz), the handset is capable of providing operation at mobile bands. 相似文献
67.
68.
Wool bleaching with sodium bisulphite in the presence of sodium lauryl sulphate has been shown to improve wool whiteness by four Berger units. A 25% decrease in cysteine content is also obtained as a consequence of the protective action of the surfactant on the keratin's disulphide linkage. 相似文献
69.
Mónica A. Pérez Carlos J. Caro Rodrigo A. Cancino Franco M. Rabagliati 《Polymer Bulletin》2003,51(3):199-208
Summary
The homo- and copolymerization of styrene (S) with
p-methylstyrene (p-MeS) and p-tert-butylstyrene
(p-ButS) has been tested using
initiator systems of the
Ph2Zn-metallocene-MAO type. The
metallocenes used were CpTiCl3,
IndTiCI3,
(n-BuCp)2TiCl2,
Ind2ZrCl2 and
Et(Ind)2ZrCl2. The
Ph2Zn-metallocene-MAO systems
homopolymerize styrene, p-methylstyrene and p-tert-butylstyrene,
producing syndiotactic polymers in the case of the titanocenes
and amorphous polymers in the case of the zirconocenes. The
S/p-MeS and S/p-ButS copolymers
obtained with the Ph2Zn-titanocene-MAO
systems are enriched in the comonomer with respect to the
initial feed. 相似文献
70.
Some new derivatives of valproic acid (1) have been synthesized by condensation reaction of L-phenylalanine ethyl ester (2), L-tryptophan methyl ester (3), L-leucine methyl ester (4), L-methionine methyl ester (5) or L-histidine methyl ester (6) with 1 in the presence of dicyclohexylcarbodiimide (DCC). The reaction afforded in good yield prodrugs containing an amino acidic moiety. The structure of the new compounds was determined with the aid of spectroscopic and analytical data. To evaluate the stability following p.o., administration, the synthesized molecules were tested for gastro-intestinal hydrolysis. No significant general acid-base hydrolysis for the peptide bond was observed. The molecules offer a potentially useful mean to obtain highly selective drug release to the brain. 相似文献