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11.
Mahesh S. Raisinghani 《Information Systems Management》2001,18(3):8-16
Wireless application protocol (WAP) is the most popular Internet-enabling technology being adopted en masse by handset manufacturers and service providers alike. This article discusses the fast-growing trend for WAP tools to access the Internet versus the current predominant use of personal computers. the article also describes the importance of WAP in the fields of E-commerce and M-commerce. 相似文献
12.
M. Mahesh Y. S. Wong J. Y. H. Fuh H. T. Loh 《The International Journal of Advanced Manufacturing Technology》2006,31(3-4):374-387
This paper presents a methodology of using six-sigma quality tools for benchmarking of rapid prototyping & manufacturing (RP&M) processes. It involves the fabrication of a geometric benchmark part and a methodology to control and identify the best performance of the process to reduce the variablity in the fabricated parts. The approach is demonstrated with a case study based on the direct laser sintering (DLS) process for prototyping using plastic powder. In the case study an identified set of six-sigma/ statistical process control tools is employed to determine and best tune factors affecting the desired outcomes of the built parts. 相似文献
13.
Mahesh Kumar Basanta Roul Thirumaleshwara N. BhatMohana K. Rajpalke A.T. KalghatgiS.B. Krupanidhi 《Thin solid films》2012,520(15):4911-4915
Ultra thin films of pure β-Si3N4 (0001) were grown on Si (111) surface by exposing the surface to radio- frequency nitrogen plasma with a high content of nitrogen atoms. Using β-Si3N4 layer as a buffer layer, GaN epilayers were grown on Si (111) substrate by plasma-assisted molecular beam epitaxy. The valence band offset (VBO) of GaN/β-Si3N4/Si heterojunctions is determined by X-ray photoemission spectroscopy. The VBO at the β-Si3N4 / Si interface was determined by valence-band photoelectron spectra to be 1.84 eV. The valence band of GaN is found to be 0.41 ± 0.05 eV below that of β-Si3N4 and a type-II heterojunction. The conduction band offset was deduced to be ~ 2.36 eV, and a change of the interface dipole of 1.29 eV was observed for GaN/β-Si3N4 interface formation. 相似文献
14.
R. Mahesh A. P. Vinod Edmund M-K. Lai Amos Omondi 《Journal of Signal Processing Systems》2011,62(2):157-171
The ability to support multiple channels of different communication standards, in the available bandwidth, is of importance
in modern software defined radio (SDR) receivers. An SDR receiver typically employs a channelizer to extract multiple narrowband
channels from the received wideband signal using digital filter banks. Since the filter bank channelizer is placed immediately
after the analog-to-digital converter (ADC), it must operate at the highest sampling rate in the digital front-end of the
receiver. Therefore, computationally efficient low complexity architectures are required for the implementation of the channelizer.
The compatibility of the filter bank with different communication standards requires dynamic reconfigurability. The design
and realization of dynamically reconfigurable, low complexity filter banks for SDR receivers is a challenging task. This paper
reviews some of the existing digital filter bank designs and investigates the potential of these filter banks for channelization
in multi-standard SDR receivers. We also review two low complexity, reconfigurable filter bank architectures for SDR channelizers
based respectively on the frequency response masking technique and a novel coefficient decimation technique, proposed by us
recently. These filter bank architectures outperform existing ones in terms of both dynamic reconfigurability and complexity. 相似文献
15.
S. Basavaraja D. S. Balaji Mahesh D. Bedre D. Raghunandan P. M. Prithviraj Swamy A. Venkataraman 《Bulletin of Materials Science》2011,34(7):1313-1317
Nanometer-sized α-Fe2O3 particles have been prepared by a simple solvothermal method using ferric acetylacetonate as a precursor. The products were characterized by X-ray diffraction (XRD), energy dispersive X-ray microanalysis (EDAX), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transition electron microscopy (TEM), infrared spectroscopy (IR) and thermal analysis (TG-DTA). XRD indicates that the product is single-phase α-Fe2O3 with rhombohedral structure. Bundles of acicular shaped nanoparticles are seen in TEM images with an aspect ratio ~ 12; typically 8–12 nm wide and over 150 nm long. The α-Fe2O3 nanoparticles posses a high thermal stability, as observed on thermal analysis traces. 相似文献
16.
The fracture behaviour of concrete is complex due to highly heterogeneous nature of the material. The heterogeneity of concrete manifests itself at various scales. At mesoscale, the presence of aggregates influences the strength of concrete by developing a zone of weakness in the form of aggregate–matrix interface. These lead to an increased distributed micro-cracking and enhances the energy absorption capacity of the material. The energy absorption capacity of structure is dependent not only on material properties but also on structural geometry and loading conditions. The present work attempts to identify the material and structural parameters that influence the overall behaviour, by using discrete numerical modelling of the material at mesoscale. Lattice modelling, a technique to model the heterogeneity using lattice elements is used to study the fracture behaviour of the material. Effect of aggregate volume fraction, specimen thickness and depth on the global behaviour is studied. 相似文献
17.
Paul V. Shanahan Lianbin Xu Chengdu Liang Mahesh Waje Sheng Dai Y.S. Yan 《Journal of power sources》2008
Highly stable graphitic mesoporous carbons (GMPCs) are synthesized by heat-treating polymer-templated mesoporous carbon (MPC) at 2600 °C. The electrochemical durability of GMPC as Pt catalyst support (Pt/GMPC) is compared with that of carbon black (Pt/XC-72). Comparisons are made using potentiostatic and cyclic voltammetric techniques on the respective specimens under conditions simulating the cathode environment of PEMFC (proton exchange membrane fuel cell). The results indicate that the Pt/GMPC is much more stable than Pt/XC-72, with 96% lower corrosion current. The Pt/GMPC also exhibits a greatly reduced loss of catalytic surface area: 14% for Pt/GMPC vs. 39% for Pt/XC-72. 相似文献
18.
19.
Computational fluid dynamics (CFD) simulations have been carried out to simulate a turbulent, bubble plume in a liquid pool. A two-fluid enhanced k-? model has been used, with the extra source terms introduced to account for the interaction between the bubbles and the liquid and transient calculations have been performed to study the plume growth, the acceleration of the liquid due to viscous drag, and the approach to steady-state conditions. In order to obtain correct spreading of the plume observed experimentally, it was observed that interfacial forces like lift and turbulent dispersion plays important role. The sensitivity analysis for drag coefficient and two different turbulent dispersion forces is presented. The development of the flow variables has been compared with the experimental data. From the CFD predictions obtained in the present work, it can be concluded that a two-dimensional (2D) axisymmetric assumption in this case is justified, with 2D model predictions in good agreement with the experimental data and those of a three-dimensional (3D) model, except for the shear stresses and turbulent kinetic energy. In general, quantitative comparison with the experimental data has revealed that, by applying proper models of inter-phase momentum transfer, and performing simulations based on the two-fluid model, satisfactory predictions of mean flow quantities can be obtained for this application away from the injector. 相似文献
20.
Microsystem Technologies - Watermarking is defined as about hiding any valuable information set in the particular digital media by itself through modifying the particular graphic contents. In our... 相似文献