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1.
Navneet Rao 《电子设计应用》2007,(12):16-16,18,20,22,24,37
SRIO IP解决方案提供真实双向数据流,大大增强连接功能。目前,对高速通信与超快计算的需求正与日俱增。有线和无线通信标准的应用随处可见,数据处理架构每天都在扩展。较为普遍的有线通信方式是以太网(LAN、WAN和MAN网络)。手机通信是最为常见的无线通信方式,由应用了DSP的  相似文献   
2.
The aim of this paper is to design a current source obtained as a representation of p information symbols \(\{I_k\}\) so that the electromagnetic (EM) field generated interacts with a quantum atomic system producing after a fixed duration T a unitary gate U(T) that is as close as possible to a given unitary gate \(U_g\). The design procedure involves calculating the EM field produced by \(\{I_k\}\) and hence the perturbing Hamiltonian produced by \(\{I_k\}\) finally resulting in the evolution operator produced by \(\{I_k\}\) up to cubic order based on the Dyson series expansion. The gate error energy is thus obtained as a cubic polynomial in \(\{I_k\}\) which is minimized using gravitational search algorithm. The signal to noise ratio (SNR) in the designed gate is higher as compared to that using quadratic Dyson series expansion. The SNR is calculated as the ratio of the Frobenius norm square of the desired gate to that of the desired gate error.  相似文献   
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The present study reports the preparation and application of a novel biopolymer-based composite hydrogel (BCH) for removal of synthetic dye rhodamine 6G (Rh6G). BCH was prepared from biopolymer chitosan and acrylic acid monomer, in the presence of initiator (K2S2O8) and cross-linker thiourea using microwave irradiation. Synthesized chitosan-based composite hydrogel was characterized by using analytical techniques including Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), derivative thermogravimetric analysis (DTA) and differential thermal analysis (DTG). The stability of the adsorbent was demonstrated from its water uptake capacity. The dynamics of water sorption study showed the Fickian behavior. The investigations were continued to assess the adsorption potential of BCH for removal of Rh6G from aqueous solution. The effect of process parameters affecting the adsorption of rhodamine 6G (Rh6G), such as adsorbent dose, initial concentration of pollutant, contact time and pH of the solution was evaluated. Removal efficiency of chitosan-based composite hydrogel (BCH) was found to be 87.31% at pH 7 for BCH dose of 1 g/L after 8 h. The obtained data were fitted to adsorption isotherms and kinetics models. The adsorption equilibrium isotherm and kinetics studies indicated that the pseudo-second-order model and the Freundlich model well described the adsorption equilibrium of Rh6G on BCH.  相似文献   
5.
This paper discusses stochastic analysis of the ash handling system in a thermal power plant. The system consists of four subsystems Ai, Bj, C and Dk in series, with three possible states: good, reduced and failed. Failure and repair rates for each subsystem are taken to be constants. Using a probabilistic approach, the differential equations are generated and the expression for steady state availability is computed. Taking data from the thermal power plant, situated in North India, the behaviour of each working unit is analysed. Problems and remedies with appropriate maintenance schedules have been discussed. The results are discussed with the plant personnel and are helpful to the management in predicting the behaviour of each operating unit, so that timely decisions can be taken for maintaining the system in upstate for a long duration.  相似文献   
6.
The present paper deals with a shop floor applicable mathematical model for deposition rate during twin-wire submerged arc welding. The salient features of this model are (1) instead of melting rate, as modeled during past investigations, it quantifies the deposition rate, which is the actual outcome of the process and always remains smaller than the melting rate because of evaporation or spatters losses and (2) it estimates electrode extension in order to predict the deposition rate which makes the proposed model more practical than the models constituted with the help of experimental measurement of electrode extension. The model is more scientific than the simplified models where contact tube to work-piece distance has been considered as the electrode extension. A critical review of the relevant past investigation is given and a mathematical model is developed for deposition rate during the twin-wire welding with both the polarities, i.e., direct current electrode positive and direct current electrode negative. The model is calibrated using the results of 200 experimental runs and it is found to be very accurate with very high coefficient of regression and admissible standard error. The developed model is further validated with extra experimental runs. The practicality of the considered approach for prediction of deposition rate can further be used in future research for other consumable arc welding processes.  相似文献   
7.
Due to variety of materials available to any designer for a particular application, there is a need for a proper technique to select. This paper focuses on the optimum selection of materials for electrostatic microactuators using Ashby approach. In this work, performance indices and material indices have been developed for electrostatic actuators and thereafter material selection chart is plotted. The selection chart shows that for high actuation voltage and high actuation force, diamond is the best possible candidate followed by silicon carbide and silicon nitride. On the other hand, if high speed electrostatic actuator is desired, then aluminum is the best possible candidate followed by nickel and copper.  相似文献   
8.
n-3 Polyunsaturated fatty acids (PUFA) have a chemopreventive effect while n-6 PUFA promote carcinogenesis. The effect of these essential fatty acids may be related to oxidative stress. Therefore, the study was designed to evaluate the effect of different ratios of fish oil (FO) and corn oil (CO) in the prevention of colon cancer. Male Wistar rats were divided into control, dimethylhydrazine dihydrochloride (DMH) treated, FO + CO (1:1) and FO + CO (2.5:1). All the groups, except the control received a weekly injection of DMH for 4 weeks. The animals were sacrificed either 48 h later (initiation phase) or kept for 16 weeks (post initiation phase). DMH treatment in the initiation phase animals showed mild to moderate inflammation, decreased ROS and TrxR activity, increased antioxidants, apoptosis and ACF multiplicity. The post initiation study showed severe inflammation with hyperplasia, increased ACF multiplicity and ROS levels, a decrease in antioxidants and apoptosis. The FO + CO (1:1) treated animals showed severe inflammation, a decrease in ROS, an increase in antioxidants and apoptosis in the initiation phase. FO + CO (1:1) in the post initiation phase and FO + CO (2.5:1) in the initiation showed mild inflammation, increased ROS, apoptosis and decreased antioxidants. There was a decrease in ACF multiplicity and ROS levels, increased antioxidants and apoptosis in the post initiation phase study. The present study suggests that FO has a dose- and time-dependent chemopreventive effect in colon cancer mediated through oxidative stress and apoptosis.  相似文献   
9.
The paper discusses the availability analysis of a steam generation system consisting of three subsystems A, B and D and a power generation system consisting of four subsystems E, F, G and H arranged in series, with three states viz., good, reduced and failed. Taking constant failure and repair rates for each working unit, the mathematical formulation is done using the Birth-Death process. Expressions for steady state availability and the MTBF (mean time between failure) are derived. The graphs are given, depicting the effect of failure and repair rates on the system availability. The results are supplied to the plant personnel, to plan the policies for failure free running of the systems for a long duration.  相似文献   
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