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91.
We reported the influence of interface trap density(Nt) on the electrical properties of amorphous InSnZnO based thin-film transistors,which were fabricated at different direct-current(DC) magnetron sputtering powers.The device with the smallest Nt of 5.68×1011 cm-2 and low resistivity of 1.21×10-3Ω·cm exhibited a turn-on voltage(VON) of-3.60 V,a sub-threshold swing(S.S) of 0.16 V/dec and an on-off ratio(ION/IOFF) of8 x 108.With increasing Nt,the VON,S.S and ION/IOFF were suppressed to-9.40 V,0.24 V/dec and 2.59×108,respectively.The VTH shift under negative gate bias stress has also been estimated to investigate the electrical stability of the devices.The result showed that the reduction in Nt contributes to an improvement in the electrical properties and stability. 相似文献
92.
Hoc Phan Hans‐Jürgen Zepernick Trung Q. Duong Hung Tran Thi My Chinh Chu 《Wireless Communications and Mobile Computing》2015,15(1):56-70
In this paper, we analyze the performance of cognitive amplify‐and‐forward (AF) relay networks with beamforming under the peak interference power constraint of the primary user (PU). We focus on the scenario that beamforming is applied at the multi‐antenna secondary transmitter and receiver. Also, the secondary relay network operates in channel state information‐assisted AF mode, and the signals undergo independent Nakagami‐m fading. In particular, closed‐form expressions for the outage probability and symbol error rate (SER) of the considered network over Nakagami‐m fading are presented. More importantly, asymptotic closed‐form expressions for the outage probability and SER are derived. These tractable closed‐form expressions for the network performance readily enable us to evaluate and examine the impact of network parameters on the system performance. Specifically, the impact of the number of antennas, the fading severity parameters, the channel mean powers, and the peak interference power is addressed. The asymptotic analysis manifests that the peak interference power constraint imposed on the secondary relay network has no effect on the diversity gain. However, the coding gain is affected by the fading parameters of the links from the primary receiver to the secondary relay network. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
93.
Ha Vu Thi Thu Nguyen Manh B. Tam Tran Nhu Thu Vu Thi Yen Pham Thi Hai Phong Pham Hong Nhiem Dao Ngoc Hung Le Quoc Hai Tran Quang 《Journal of Applied Electrochemistry》2022,52(3):607-616
Journal of Applied Electrochemistry - In this study, a sensitive and selective electrochemical sensor based on a zirconia oxide-decorated gold nanoflake nanocomposite-modified glassy carbon... 相似文献
94.
95.
Dao Thi Nhung 《Computer Physics Communications》2009,180(11):2258-2267
We present a new Fortran code to calculate the scalar one-loop four-point integral with complex internal masses, based on the method of 't Hooft and Veltman. The code is applicable when the external momenta fulfill a certain physical condition. In particular it holds if one of the external momenta or a sum of them is timelike or lightlike and therefore covers all physical processes at colliders. All the special cases related to massless external particles are treated separately. Some technical issues related to numerical evaluation and Landau singularities are discussed. 相似文献
96.
97.
Nguyen Thi Huong Lien Hajime Nobuhara Fangyan Dong Kaoru Hirota 《Signal, Image and Video Processing》2009,3(2):115-126
To robustly and imperceptibly embed copyright information as a watermark into music clips, a two channel digital watermarking
system based on the least significant bit (LSB) method and echo hiding (EH) with a new exponential time-spread echo kernel
(ETEK) is proposed. By spreading the echo so that it seems like natural room reverberation, as well as the use of two channels
to separately watermark by the LSB method and the EH method which have complementary characteristics, the system provides
satisfactory sound quality and exhibits both efficient retrieval capacity and robustness against attacks. Experiments show
that the proposed system retrieves watermarks with 100% accuracy for all clips and is almost imperceptible. With a set of
42 attacks supplied by the StirMark Benchmark for Audio (SMBA), the proposed system has an average robustness of 0.98 where
the ideal value is 1.00, and higher than any conventional methods. With these results, the proposed system is shown to be
possible for the application to music distribution over the Internet. 相似文献
98.
Historical land-cover changes in three delta regions in Southeast Asia are assessed by using selected Landsat images from 1990 to 2005. Potential inundation areas of the delta regions for different return periods are estimated by using digital elevation model data and extreme-value distribution of annual maximum river discharges. The results indicate significant changes of natural land cover within the potential inundation areas due to agricultural exploitation and industrialization. Implications for flood-mitigation policies are discussed. There is a clear need for sustainable land-use management strategies in all three areas. 相似文献
99.
Understanding the uncertainty of climate models in space and time is necessary to help water resources managers and hydrologists in the selection of appropriate model for a specific application. In this paper, we use three separate methods to evaluate and compare the utility of 14 climate models for seven basins with area range of 2,656–26,355 km2 on the South Korean Peninsula. On the one hand, the method of probabilistic uncertainty analysis is used to evaluate the capability of the studied General Circulation Models (GCMs) in recognizing the extreme events. On the other hand, we use two statistical tests (correlation coefficient and root mean square error) to examine the capability of the GCMs in simulating quantitatively each event. The results show that, for the first method, the performance of climate model varies depending on the number of climate model nodes used for a specific application of given basin, especially for monthly time scale. In addition, we find that, there are several GCMs showing good results for the probabilistic uncertainty test but poor results for the statistical test and conversely. Therefore, climate models should be evaluated for specific applications and specific regions. The results indicated quite clearly that, it is not easy to select an optimal climate model which can satisfy both applications using precipitation and temperature projections. However, the results of this study suggest that, there are several GCMs which are more useful than the others for general hydrological application in South Korean peninsula. 相似文献
100.