1,305 research outputs found
Pixel Arrangement and Mapping Algorithm for Improving Saturation and Brightness
With the increasing demand for display effects and resolution in the display market, the traditional RGBW permutation has defects such as reduced display saturation and poor image restoration. A new sub-pixel arrangement is designed for these defects, reducing the number of white pixels W and adding yellow pixels Y, which reduces the influence of white pixels on surrounding pixels compared to the conventional RGBW structure. According to the new arrangement method, two new mapping algorithms are designed, and the saturation concept is introduced. The yellow component and the white component are adjusted by the saturation change to effectively improve the image saturation. The simulation shows that the new mapping algorithm (1) has a higher degree of restoration on the image and increases the saturation by 10%. The new mapping algorithm (2) can improve the brightness based on maintaining the high saturation of the original image
Secrecy outage analysis for Alamouti space-time block coded non-orthogonal multiple access
This letter proposed a novel transmission technique for physical layer security by applying the Alamouti Space-Time Block Coded Non-orthogonal Multiple Access (STBC-NOMA) scheme. The secure outage performance under both perfect successive interference cancellation (pSIC) and imperfect successive interference cancellation (ipSIC) are investigated. In particular, novel exact and asymptotic expressions of secrecy outage probability are derived. Numerical and theoretical results are presented to corroborate the derived expressions and to demonstrate the superiority of STBC-NOMA and its ability to enhance the secrecy outage performance compared to conventional NOMA
System-level modelling and validation of a strain energy harvesting system by directly coupling finite element and electrical circuits
This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.— There is a lack of system-level finite element (FE)
model which can directly predict the performance of a
piezoelectric energy harvester connected with interface circuits
and electric load. This work developed a system-level model of
piezoelectric strain energy harvesting system by directly coupling
the finite element and electrical circuits. The strain energy
harvester (SEH) is a macro fibber composite adhesively bonded
to a composite beam. Simulations were performed with the SEH
connected with three circuits individually (i) a load resistor, (ii) a
rectifier terminated with a load resistor and (iii) a rectifier
terminated with a smoothing capacitor and a load resistor.
Experimental tests were carried out to validate the simulation
results. Good agreements were observed between the simulated
and measured results. The developed model is able to predict the
performance of the energy harvesting system when different
circuit was connected. The validated system-level model can be
used for the design and optimization of piezoelectric energy
harvesting system by investigating the interactions between
energy harvester and electrical circuits
A Filter Algorithm with Inexact Line Search
A filter algorithm with inexact line search is proposed
for solving nonlinear programming problems. The filter is constructed by employing
the norm of the gradient of the Lagrangian function to the infeasibility
measure. Transition to superlinear local convergence is showed for the proposed
filter algorithm without second-order correction. Under mild conditions, the
global convergence can also be derived. Numerical experiments show the efficiency
of the algorithm
Guaranteed Lower Eigenvalue Bound of Steklov Operator with Conforming Finite Element Methods
For the eigenvalue problem of the Steklov differential operator, by following
Liu's approach, an algorithm utilizing the conforming finite element method
(FEM) is proposed to provide guaranteed lower bounds for the eigenvalues. The
proposed method requires the a priori error estimation for FEM solution to
nonhomogeneous Neumann problems, which is solved by constructing the
hypercircle for the corresponding FEM spaces and boundary conditions. Numerical
examples are also shown to confirm the efficiency of our proposed method.Comment: 21 pages, 4 figures, 4 table
- …