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91.
Babu P.N. Govind G. Prasad S.M.S. Bhat K.N. 《Device and Materials Reliability, IEEE Transactions on》2007,7(3):420-428
In this paper, we report the electrical characteristics and reliability studies on tunnel oxides fabricated by "wet N2O" oxidation of silicon in an ambient of water vapor and N2O at a furnace temperature of 800 degC. Tunnel oxides that have an equivalent oxide thickness of 67 A are subjected to a constant-current stress (CCS) amount of -100 mA/cm2 using a MOS capacitor to obtain information on stress-induced leakage current (SILC), interface, and bulk trap generation. The obtained results clearly demonstrate the superior performance features of the present tunnel oxides with reduced SILC, lower trap generation, minimum change in gate voltage, and higher charge-to-breakdown during CCS studies. X-ray photoelectron spectroscopy depth profile studies of the tunnel oxide interfaces have shown that the improved performance characteristics and reliability can be attributed to the incorporation of about 8.5% nitrogen at the oxide-silicon interface of the samples formed by the "wet N2O" process that involves low-temperature oxidation and annealing at 800 degC. 相似文献
92.
Non‐Volatile ReRAM Devices Based on Self‐Assembled Multilayers of Modified Graphene Oxide 2D Nanosheets 下载免费PDF全文
Adila Rani Dhinesh Babu Velusamy Richard Hahnkee Kim Kyungwha Chung Filipe Marques Mota Cheolmin Park Dong Ha Kim 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(44):6167-6174
2D nanomaterials have been actively utilized in non‐volatile resistive switching random access memory (ReRAM) devices due to their high flexibility, 3D‐stacking capability, simple structure, transparency, easy fabrication, and low cost. Herein, it demonstrates re‐writable, bistable, transparent, and flexible solution‐processed crossbar ReRAM devices utilizing graphene oxide (GO) based multilayers as active dielectric layers. The devices employ single‐ or multi‐component‐based multilayers composed of positively charged GO (N‐GO(+) or NS‐GO(+)) with/without negatively charged GO(‐) using layer‐by‐layer assembly method, sandwiched between Al bottom and Au top electrodes. The device based on the multi‐component active layer Au/[N‐GO(+)/GO(‐)]n/Al/PES shows higher ON/OFF ratio of ≈105 with switching voltage of ?1.9 V and higher retention stability (≈104 s), whereas the device based on single component (Au/[N‐GO(+)]n/Al/PES) shows ≈103 ON/OFF ratio at ±3.5 V switching voltage. The superior ReRAM properties of the multi‐component‐based device are attributed to a higher coating surface roughness. The Au/[N‐GO(+)/GO(–)]n/Al/PES device prepared from lower GO concentration (0.01%) exhibits higher ON/OFF ratio (≈109) at switching voltage of ±2.0 V. However, better stability is achieved by increasing the concentration from 0.01% to 0.05% of all GO‐based solutions. It is found that the devices containing MnO2 in the dielectric layer do not improve the ReRAM performance. 相似文献
93.
B. Krishna Mohan B. Babu Madhavan U. M. Das Gupta 《International journal of remote sensing》2013,34(8):1709-1723
A methodology has been formulated to integrate images from IRS-1A LISS II of two dates for landuse/landcover classification. The methodology developed includes image classification by fuzzy k-means clustering and fusion of memberships by fuzzy set theoretic operators. The two date images have been geometrically coregistered and classified for the identification of land classes individually. The fuzzy memberships of the classified output images have been integrated by using fuzzy logic operators like algebraic sum and gamma (gamma) operator. The classification accuracy of the resultant land classes in the integrated images was verified with the ground data collected in situ. The resultant images have been evaluated by kappa (kappa) statistic and it was found that output from the image of fuzzy algebraic sum operator scored high in generating the land classes, with an overall accuracy of 95%. 相似文献
94.
This study attempted to quantify the variations of the surface marine atmospheric boundary layer (MABL) parameters associated with the tropical Cyclone Gonu formed over the Arabian Sea during 30 May–7 June 2007 (just after the monsoon onset). These characteristics were evaluated in terms of surface wind, drag coefficient, wind stress, horizontal divergence, and frictional velocity using 0.5° × 0.5° resolution Quick Scatterometer (QuikSCAT) wind products. The variation of these different surface boundary layer parameters was studied for three defined cyclone life stages: prior to the formation, during, and after the cyclone passage. Drastic variations of the MABL parameters during the passage of the cyclone were observed. The wind strength increased from 12 to 22 m s?1 in association with different stages of Gonu. Frictional velocity increased from a value of 0.1–0.6 m s?1 during the formative stage of the system to a high value of 0.3–1.4 m s?1 during the mature stage. Drag coefficient varied from 1.5 × 10?3 to 2.5 × 10?3 during the occurrence of Gonu. Wind stress values varied from 0.4 to 1.1 N m?2. Wind stress curl values varied from 10 × 10?7 to 45 × 10?7 N m?3. Generally, convergent winds prevailed with the numerical value of divergence varying from 0 to –4 × 10?5 s?1. Maximum variations of the wind parameters were found in the wall cloud region of the cyclone. The parameters returned to normally observed values in 1–3 days after the cyclone passage. 相似文献
95.
ABSTRACTInjection timing (IT) is a vital factor among different injection parameters which governs the emissions and performance factors of the engine. This work portrays the effect of IT on cerium oxide nanoparticle doped Waste Cooking Palm Oil biodiesel and diesel blends. The doping is made at 30, 60 and 90?ppm. The modified fuels are introduced in reducing IT of 19°, 21° and 23°bTDC. 1500?rpm engine is made use in this study. Results revealed a significant reduction in emissions (CO, NOX, HC and Smoke) at IT?=?23°bTDC. Furthermore, performance (BSFC, BTE) is improved for fuel blends at IT?=?23°bTDC. 相似文献
96.
K. Kamal Babu K. Panneerselvam P. Sathiya A. Noorul Haq S. Sundarrajan P. Mastanaiah C. V. Srinivasa Murthy 《The International Journal of Advanced Manufacturing Technology》2018,94(9-12):3117-3129
In this paper, parameter optimization of FSW of cryorolled AA2219 alloy was carried out to obtain defect free weld joint with maximum weld strength. To achieve this, artificial neural network (ANN) was used to model the relationship between the input parameters and the mechanical and corrosion properties (output) of the weld joints. The optimal FSW parameters were determined by genetic algorithm (GA). The feasible solution of the GA was tool rotational speed of 1005 rpm, tool travel speed of 20 mm/min and tool tilt angle of 3°. The feasible parameter was used to weld and check the ability of the parameter to produce better weld joint than the L9 orthogonal array parameters. The weld, subjected to the confirmation test, was investigated by means of metallurgical, mechanical, and corrosion testing. This process reduces the costs associated with trial runs to obtain optimal parameters and also the production cost of the cryorolled (CR) plate which is high. 相似文献
97.
This paper considers cooperative non‐orthogonal multiple access (NOMA) scheme in an underlay cognitive radio (CR) network. A single‐cell downlink cooperative NOMA system has been considered for the secondary network, consisting of a base station (BS) and two secondary users, ie, a far user and a near user. The BS employs NOMA signaling to send messages for the two secondary users where the near user is enabled to act as a half‐duplex decode‐and‐forward (DF) relay for the far user. We derive exact expressions for the outage probability experienced by both the users and the outage probability of the secondary system assuming the links to experience independent, nonidentically distributed Rayleigh fading. Further, we analyze the ergodic rates of both the users and the ergodic sum rate of the secondary network. The maximum transmit power constraint of the secondary nodes and the tolerable interference power constraint at the primary receiver are considered for the analysis. Further, the interference caused by the primary transmitter (PT) on the secondary network is also considered for the analysis. The performance of the proposed CR NOMA network has been observed to be significantly better than a CR network that uses conventional orthogonal multiple access (OMA) scheme. The analytical results are validated by extensive simulation studies. 相似文献
98.
Anbarasi A. Ravi S. Vaishnavi J. Matla S. V. Suresh Babu 《Multimedia Tools and Applications》2021,80(14):21409-21424
Multimedia Tools and Applications - The significance of mitral valve (MV) treatment is increasing recently because of an aging population. The computer vision-based acquisition and quantification... 相似文献
99.
Benjamin Shassere Yukinori Yamamoto Jonathan Poplawsky Wei Guo Sudarsanam Suresh Babu 《Metallurgical and Materials Transactions A》2017,48(10):4598-4614
A new Fe-Cr-Al (FCA) alloy system has been developed with good oxidation resistance and creep strength at high temperature. The alloy system is a candidate for use in future fossil-fueled power plants. The creep strength of these alloys at 973 K (700 °C) was found to be comparable with traditional 9 pct Cr ferritic–martensitic steels. A few FCA alloys with general composition of Fe-30Cr-3Al-.2Si-xNb (x = 0, 1, or 2) with a ferrite matrix and Fe2Nb-type Laves precipitates were prepared. The detailed microstructural characterization of samples, before and after creep rupture testing, indicated precipitation of the Laves phase within the matrix, Laves phase at the grain boundaries, and a 0.5 to 1.5 μm wide precipitate-free zone (PFZ) parallel to all the grain boundaries. In these alloys, the areal fraction of grain boundary Laves phase and the width of the PFZ controlled the cavitation nucleation and eventual grain boundary ductile failure. A phenomenological model was used to compare the creep strain rates controlled by the effects of the particles on the dislocations within the grain and at grain boundaries. (The research sponsored by US-DOE, Office of Fossil Energy, the Crosscutting Research Program). 相似文献
100.
The development of the semi-theoretical correlation in Hadzisdmajlovic et al. (1983) for predicting the maximum spoutable height in a spout-fluid bed, is observed to involve certain discrepancies. Based on their experimental data, a new correlation is proposed. 相似文献