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71.
A method of optimal beamforming for flat Rayleigh faded channels using the Fractional Fourier Transform (FRFT) is considered
in this paper. It has been demonstrated through simulations that optimal beamforming with FRFT allows smaller mean-square
errors in restoring signals degraded with linear time-or frequency variant distortions and Additive White Gaussian Noise.
This is made possible by the additional flexibility that comes with free parameter ‘a’ of the fractional Fourier transform as oppose to the classical Fourier transform (FT). The method is especially useful in
moving source problems, where Doppler Effect produces frequency shift when the source is moving, as in mobile and wireless
communication where user produces the frequency shift while moving. In this paper it is shown through simulations that beamforming
in fractional domain reduces BER as compared to time or frequency domain. 相似文献
72.
Yogi Priyanka Poonia Deepika Yadav Pooja Mishra Suryakant Saxena Shailendra K. Roy Swarup Sagdeo Pankaj R. Kumar Rajesh 《SILICON》2018,10(6):2801-2807
Silicon - Nano-metal/semiconductor junction dependent porosification of silicon has been studied here. The silicon nanostructures (SiNSs) have been textured on n- and p- type silicon wafers using... 相似文献
73.
A finite element creep analysis of a center crack specimen has been carried out under small scale to extensive creep conditions. The crack was assumed to be stationary. Several constitutive models were used; these consisted of elastic, power-law creep with and without rate-independent plasticity, as well as one which also included primary creep. The mechanics basis of the C
t parameter, which has been proposed for correlating creep crack growth behavior under conditions ranging from small scale to extensive creep, is explored.For the aforementioned specimen geometry, consideration of primary creep seems to explain the differences between the measured and previously calculated load line deflection rates based on power-law creep only. It is also concluded that in small scale creep, C
t does not characterize the instantaneous crack tip singular stress field, but it accurately characterizes the rate of expansion of the crack tip creep zone regardless of whether primary or secondary creep is occurring. This result provides a rationale for using C
t to correlate creep crack growth rates even in the presence of significant primary creep deformation.
Résumé On a procédé à une analyse par éléments finis du fluage d'une éprouvette comportant une fissure centrale, sous des conditions allant du fluage à petite échelle jusqu'à un fluage important. On suppose que la fissue est stationaire. Divers modèles ont été utilisés, à savoir la loi de fluage élastique ou parabolique, avec ou sans plasticité indépendante de la vitesse, ainsi qu'une loi incluant également le fluage primaire. On a étudié la base mécanistique du paramètre C t, proposé pour relier le comportement de la croissance de la fissure de fluage sous des conditions entraînant un fluage depuis une petite échelle jusqu'à une grande échelle.Pour la géométrie citée, les différences entre les vitesses de variation de la courbe de la charge, mesurées et précédemment calculées en se basant sur la seule loi parabolique de fluage, semblent applicables par la prise en considération du fluage primaire. On conclut également que lors de fluage à petite échelle, C t ne caractérise pas le champ singulier de contraintes instantanées à l'extrémité de la fissure, mais plutôt, et de maniére sûre, la vitesse d'extension de la zone de fluage à l'extrémité de la fissure, qu'il y ait fluage primaire ou fluage secondaire. Ce tésultat fournit une base d'utilisation de C t pour connaître les vitesses de croissance d'une fissure de fluage, même en présence d'une déformation de fluage primaire significative.相似文献
74.
Bhogal Sangeeta Sharma Gaurav Kumar Amit Sharma Shweta Naushad Mu. Alam Manawwer Stadler Florian J. 《Topics in Catalysis》2020,63(11-14):1272-1285
Topics in Catalysis - In the present study, Ag2O–Al2O3–ZrO2 based trimetallic oxide nanocatalyst was designed using simple microwave assisted reduction method. It was characterized... 相似文献
75.
Satyendra K. Tripathi Khushboo Kesharwani Grace Kaul Abdul Akhir Deepanshi Saxena Dr. Ramesh Singh Dr. Narendra K. Mishra Prof. Archna Pandey Dr. Sidharth Chopra Dr. Khashti B. Joshi 《ChemMedChem》2022,17(15):e202200251
An amyloid-β inspired biocompatible short peptide amphiphile (sPA) molecule was used for controlled and targeted delivery of bioactive silver nanoparticles via transforming sPA nanostructures. Such sPA-AgNPs hybrid structures can be further used to develop antibacterial materials to combat emerging bacterial resistance. Due to the excellent antibacterial activity of silver, the growth of clinically relevant bacteria was inhibited in the presence of AgNPs-sPA hybrids. Bacterial tests demonstrated that the high biocompatibility and low cytotoxicity of the designed sPA allow it to work as a model drug delivery agent. It therefore shows great potential in locally addressing bacterial infections. The results of our study suggest that these nanodevices have the potential to trap and then engage in the facile delivery of their chemical payload at the target site, thereby working as potential delivery materials. This system has potential therapeutic value for the treatment of microbiota triggered progression of neurodegenerative diseases. 相似文献
76.
Roy Partha Pratim Kumar Pradeep Patidar Shweta Saini Rajkumar 《Multimedia Tools and Applications》2021,80(8):11671-11689
Multimedia Tools and Applications - Leap motion sensor provides a new way of interaction with computers or mobile devices. With this sensor, users can write in air by moving palm or finger, thus,... 相似文献
77.
Kumari Asha Neeraj Kumar Biswas Sakshi Saxena Vibha Rani Satsangi Rohit Shrivastav Rama Kant Sahab Dass 《International Journal of Hydrogen Energy》2021,46(40):20858-20870
The present study attempts quantitative determination of changes in the morphological surface features viz. fractal dimension, lower and upper cut off length scale through Power Spectral Density analysis prior to and after irradiation of 100 KeV Ar+ ion beam at incidence angles of 0°, 40° and 60° on ZnO thin films. All the unirradiated and irradiated samples are subjected to photoelectrochemical characterization and a correlation between photoelectrochemical performance and morphological parameters is established. Sample irradiated at 40° angle at the fluence of 5 × 1016 ions/cm2 is found to possess maximum fractal dimension of 2.72, lower and upper cut off length scale of 3.16 nm and 63.00 nm respectively. This sample exhibits maximum photocurrent density of 3.19 mA/cm2 and applied bias photon-to-current efficiency of 1.12% at 1.23 V/RHE. Hydrogen gas collected for duration of 1 h for the same sample was ~4.83 mLcm?2. 相似文献
78.
Thakur Surendra Singh Pradhan Sharad K. Sehgal Shankar Saxena Kuldeep K. 《SILICON》2023,15(1):583-601
Silicon - In this study, silicon carbide mixed electrical discharge machining (SCMEDM) process has been developed and later on modelled also using an artificial neural network (ANN) based technique... 相似文献
79.
Title of program: REDUCED TENSOR MATRIX ELEMENTS 2 Catalogue number: AAKP Program obtainable from: CPC Program Library, Queen's University of Belfast N. Ireland (see application form in this issue) Computer: Installation: IBM 360/75 University of Waterloo, Waterloo, Ont. Canada Operating system: OS/360 HASP II Programming languages used: FORTRAN IV High speed store required: 102 K bytes No. of bits per byte: 8 Overlay structure: None Other peripherals used: Card reader, line printer No. of cards in combined program and test deck: 1524 Card punching code: EBCDIC 029CPC Library subprograms used:
Cat. numbers | Titles | Refs. in C.P.C. |
ACQB | P SHELL CFP | 1 (1969) 15 |
ACRN | A NEW D SHELL CFP | 6 (1973) 88 |
AAGD | NJSYM | 1 (1970) 241, 2 (1971) 173 |
AAGD0001 | ADAPT NJSYM FOR WEIGHTS | 2 (1971) 180 |
AAGD0002 | ADAPT TO INTEGER ARITHMETIC | 5 (1973) 161 |