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The morphology and the electro-kinetic parameters of lead electrodeposits on polycrystalline lead have been studied in a fluoborate bath at several current densities in the presence of known concentrations of 2-mercaptoethanol. It was observed that there was a notable decrease in the grain-size at low concentrations of the addition agent and the critical concentration varied with the current density. The growth habit modification and the changes in the kinetic parameters with increasing concentrations of the addition agent and current density, were investigated. Suitable transport mechanisms were proposed with the help of IR and X-ray studies. 相似文献
174.
Bhupeshwaran Mani A. Jawahar S. Radha K. Chitra A. Sivasubramanian 《Photonic Network Communications》2016,32(1):73-88
Here, we discuss the influence of higher-order nonlinear effects like third-order dispersion, intra-pulse Raman scattering, and self-steepening effects on 1-ps soliton pulse shift or displacement from its initial position. The temporal shifts of soliton due to these higher-order nonlinear effects were studied numerically by “Method of Moments” to realize the contribution of these HOE on shifts. Further, we note the influence of positive and negative TOD on the shift produced by the combined HOE. The soliton shift is then analyzed in 160-Gbps telecommunication system implemented with conventional single-mode fiber (C-SMF) for the length 10 and 20 km. The disturbances between the adjacent soliton pulses in noted with different 16-bit data sequences, and the deterioration of system is characterized in terms of quality factor. It could be seen for an unchirped soliton of pulsewidth \(T_{\mathrm{o}}\sim 1\hbox {ps}\), the shift is highly influenced due to intra-pulse Raman scattering, while the shifting due to third-order dispersion can be treated negligibly small. Moreover, negative TOD was expected to inhibit the soliton temporal shift such that it would reduce collision with adjacent pulses; it results in more resonant radiation resulting in pulse decaying. Although negative TOD helps in good reception of pulses for 10 km, it fails to perform in system with 20 km C-SMF, where the dispersive components break more and more while traveling along the length of fiber. 相似文献
175.
Nakade Radha Mercer Eric Aldous Peter Storey Kyle Ogles Benjamin Hooker Joshua Powell Sheridan Jacob McCarthy Jay 《Innovations in Systems and Software Engineering》2019,15(3-4):289-306
Innovations in Systems and Software Engineering - Many of the correctness properties afforded by task-parallel programming models such as OpenMP, Cilk, X10, Chapel, Habanero, etc. rely on data-race... 相似文献
176.
ABSTRACTHealth Information Exchanges (HIEs) hold the promise to integrate patient data residing across disparate information systems in various hospitals to improve care coordination, patient engagement, and provisioning of real-time information to physicians. This research posits that collaboration is the key to HIE’s success. Drawing from the extant literature on collaboration, we discuss collaboration-related challenges that healthcare IT leaders are facing and provide normative guidelines that they can implement during the HIE initiation phase as well as the maintenance phase. 相似文献
177.
Wireless visual sensor network (WVSN) consists of a large number of nodes that are capable of acquiring, compressing and transmitting images. Surveillance becomes a vital application area of WVSN as they can be deployed in various environments to monitor and collect information. The lifetime of the nodes in the network depends on the energy consumption. Hence in this paper, block compressed sensing (BCS) based image transmission technique that utilizes Energy based Reweighted sampling (ERWS) in Modified Fast Haar Wavelet Transform (MFHWT) domain is proposed to reduce energy consumption considerably. Sparse binary random matrix is used to acquire CS measurements in MFHWT domain. In addition, the proposed technique also maintains the image quality. The developed algorithm is applied and tested for a car parking lot monitoring system. It is evident from the simulation results that the proposed method achieves better PSNR values even for fewer measurements. Experimental analysis is performed using Atmega 128 processor of Mica mote in WinAVR by Atmel. The proposed method has approximately 85.5% lesser energy consumption than other Compressed Sensing (CS) methods. Lossless Entropy Coding is applied to the ERWS measurements and considerable reduction in number of transmitted bits is also achieved. The algorithm has also been tested in WINGZ mote in real time. 相似文献
178.
Radha Thangaraj Millie Pant Kusum Deep 《Engineering Applications of Artificial Intelligence》2010,23(5):820-829
Optimization of directional over-current relay (DOCR) settings is an important problem in electrical engineering. The optimization model of the problem turns out to be non-linear and highly constrained in which two settings namely time dial setting (TDS) and plug setting (PS) of each relay are considered as decision variables; the sum of the operating times of all the primary relays, which are expected to operate in order to clear the faults of their corresponding zones, is considered as an objective function. In the present study, three models are considered namely IEEE 3-bus model, IEEE 4-bus model and IEEE 6-bus model. To solve the problem, we have applied five newly developed versions of differential evolution (DE) called modified DE versions (MDE1, MDE2, MDE3, MDE4, and MDE5). The results are compared with the classical DE algorithm and with five more algorithms available in the literature; the numerical results show that the modified DE algorithms outperforms or perform at par with the other algorithms. 相似文献
179.
Real-time streaming of audiovisual content over the Internet is emerging as an important technology area in multimedia communications. Due to the wide variation of available bandwidth over Internet sessions, there is a need for scalable video coding methods and (corresponding) flexible streaming approaches that are capable of adapting to changing network conditions in real time. In this paper, we describe a new scalable video-coding framework that has been adopted recently by the MPEG-4 video standard. This new MPEG-4 video approach, which is known as Fine-Granular-Scalability (FGS), consists of a rich set of video coding tools that support quality (i.e., SNR), temporal, and hybrid temporal-SNR scalabilities. Moreover, one of the desired features of the MPEG-J FGS method is its simplicity and flexibility in supporting unicast and multicast streaming applications over IF 相似文献
180.
Results on the temperature dependence of the electrical resistivity of single-phase silver-doped Y-Ba-Cu-O pellets and tapes, prepared by a coprecipitation technique, are presented. The excess electrical conductivity nearT>T
c
is analyzed using Aslamzov-Larkin (AL) formulations. Silver addition in Y-Ba-Cu-O influences strongly the temperature range of both the 3D and 2D regions. The lower limit of the breakdown temperature of the mean-field region (x=–0.5) shifts toward higher temperatures as the concentration of Ag increases in Y-Ba-Cu-O. For samples with higher Ag contents, a third region with critical exponent x=–0.28 is seen beyond the mean-field region. This possibly indicates the appearance of a fully critical 3D region, where dynamic scaling theory applies. 相似文献