scholarly journals Local Measurement and Diffusion Reconstruction for Signals on a Weighted Graph

2018 ◽  
Vol 2018 ◽  
pp. 1-8
Author(s):  
Yingchun Jiang ◽  
Ting Li
Keyword(s):  
Real Life ◽  
Weighted Graph ◽  
Local Measurement ◽  
Original Signal ◽  
Bandlimited Signals ◽  
Simulation Results ◽  
And Diffusion ◽  
Unweighted Graph ◽  
Improved Algorithm

Bandlimited graph signals on an unweighted graph can be reconstructed by its local measurement, which is a generalization of decimation. Since most signals are weighted in real life, we extend and improve the iterative local measurement reconstruction (ILMR) by introducing the diffusion operators to reconstruct bandlimited signals on a weighted graph. We prove that the proposed reconstruction converges to the original signal. Moreover, the simulation results demonstrate that the improved algorithm has better convergence and has robustness against noise.

Fem Simulation of Micro-Rotating-Structures and Their Applications in Measurement of Residual Stresses in Thin Films

1997 ◽  
Vol 505 ◽  
Author(s):  
Xin Zhang ◽  
Tong-Yi Zhang ◽  
Yitshak Zohar
Keyword(s):  
Thin Films ◽  
Residual Stresses ◽  
Fem Simulation ◽  
Sensitivity Factor ◽  
Local Measurement ◽  
Micro Structure ◽  
Micro Raman Spectroscopy ◽  
Before And After ◽  
Polysilicon Films ◽  
Simulation Results

ABSTRACTFEM simulation of micro-rotating-structures was performed for local measurement of residual stresses in thin films. A sensitivity factor is introduced, studied and tabulated from the simulation results. The residual stress can be evaluated from the rotating deflection, the lengths of rotating and fixed beams, and the sensitivity factor. The micro-structure technique was applied to measure residual stresses in both silicon nitride and polysilicon thin films, before and after rapid thermal annealing (RTA), and further confirmed by wafer curvature method. Residual stresses in polysilicon films at different RTA stages were also characterized by micro-Raman spectroscopy (MRS). The experimental results indicate that micro-rotating-structures indeed have the ability to measure spatially and locally residual stresses in MEMS thin films with appropriate sensitivities.

scholarly journals Security Analysis and Improvement of an Image Encryption Cryptosystem Based on Bit Plane Extraction and Multi Chaos

Entropy ◽  
2021 ◽  
Vol 23 (5) ◽  
pp. 505
Author(s):  
Shuqin Zhu ◽  
Congxu Zhu
Keyword(s):  
Image Encryption ◽  
Random Sequence ◽  
Security Analysis ◽  
Encryption Algorithm ◽  
Original Algorithm ◽  
Plane Extraction ◽  
Bit Plane ◽  
Bit Planes ◽  
And Diffusion ◽  
Improved Algorithm

This paper analyzes the security of image encryption systems based on bit plane extraction and multi chaos. It includes a bit-level permutation for high, 4-bit planes and bit-wise XOR diffusion, and finds that the key streams in the permutation and diffusion phases are independent of the plaintext image. Therefore, the equivalent diffusion key and the equivalent permutation key can be recovered by the chosen-plaintext attack method, in which only two special plaintext images and their corresponding cipher images are used. The effectiveness and feasibility of the proposed attack algorithm is verified by a MATLAB 2015b simulation. In the experiment, all the key streams in the original algorithm are cracked through two special plaintext images and their corresponding ciphertext images. In addition, an improved algorithm is proposed. In the improved algorithm, the generation of a random sequence is related to ciphertext, which makes the encryption algorithm have the encryption effect of a “one time pad”. The encryption effect of the improved algorithm is better than that of the original encryption algorithm in the aspects of information entropy, ciphertext correlation analysis and ciphertext sensitivity analysis.

scholarly journals Short Transient Parameter-Varying IIR Filter Based on Analog Oscillatory System

2019 ◽  
Vol 9 (10) ◽  
pp. 2013 ◽  
Author(s):  
Piotr Okoniewski ◽  
Jacek Piskorowski
Keyword(s):  
Transient Response ◽  
Real Life ◽  
Digital Filtering ◽  
Oscillatory System ◽  
Optimization Method ◽  
Infinite Impulse Response ◽  
Iir Filter ◽  
Dynamical Properties ◽  
Simulation Results ◽  
Discretization Process

This paper presents a concept for digital infinite impulse response (IIR) lowpass filter with reduced transient response. The proposed digital filtering structure is based on an analog oscillatory system. In order to design the considered digital filter, the analog prototype is subjected to a discretization process and, then, the parameters describing the dynamical properties of the oscillatory system are temporarily varied in time, so as to suppress the transient response of the designed filter. An optimization method, aimed at reducing the settling time by proper parameter manipulation, is presented. Simulation results, along with a real-life application proving the usefulness of the proposed concept, are also shown and discussed.

Research on a Dynamic Binary Stack Anti-Collision Algorithm

2012 ◽  
Vol 268-270 ◽  
pp. 1426-1431
Author(s):  
Jian Jun Yi ◽  
Fei Luo ◽  
Shao Li Chen ◽  
Bai Yang Ji ◽  
Hai Xu Yan
Keyword(s):  
The Other ◽  
Application System ◽  
Key Technology ◽  
Rfid Systems ◽  
Simulation Results ◽  
Better Than ◽  
Improved Algorithm

RFID anti-collision technology is one of a key technology in RFID application system. Anti-collision algorithms for RFID systems include tag anti-collision algorithms and reader anti-collision algorithms. This paper focused on the impoved binary algorithm and dynamic binary algorithm. An improved algorithm has been proposed, in which the collision bits was put into the stack and they were used as the reader’s request. Based on this mechanism, a novel binary stack algorithm has been proposed. Its simulation was given to analyze the performance of this algorithm. The simulation results showed that the amount of transmitted data in proposed algorithm was obviously less than those in the other two traditional algorithms with the number of tags and their bytes increasing. Consequently, the performance of the proposed algorithm is much better than that of the traditional anti-collision binary algorithm.

scholarly journals Modified One-Parameter Liu Estimator for the Linear Regression Model

2020 ◽  
Vol 2020 ◽  
pp. 1-17
Author(s):  
Adewale F. Lukman ◽  
B. M. Golam Kibria ◽  
Kayode Ayinde ◽  
Segun L. Jegede
Keyword(s):  
Linear Regression ◽  
Regression Model ◽  
Linear Regression Model ◽  
Ridge Regression ◽  
Real Life ◽  
Liu Estimator ◽  
Real Life Data ◽  
Squared Prediction Error ◽  
Simulation Results ◽  
Better Than

Motivated by the ridge regression (Hoerl and Kennard, 1970) and Liu (1993) estimators, this paper proposes a modified Liu estimator to solve the multicollinearity problem for the linear regression model. This modification places this estimator in the class of the ridge and Liu estimators with a single biasing parameter. Theoretical comparisons, real-life application, and simulation results show that it consistently dominates the usual Liu estimator. Under some conditions, it performs better than the ridge regression estimators in the smaller MSE sense. Two real-life data are analyzed to illustrate the findings of the paper and the performances of the estimators assessed by MSE and the mean squared prediction error. The application result agrees with the theoretical and simulation results.

The Ten Commandments for Translating Simulation Results Into Real-life Performance

2008 ◽  
Vol 40 (1) ◽  
pp. 98-109 ◽  
Author(s):  
Ivo Wenzler
Keyword(s):  
Performance Improvement ◽  
Real Life ◽  
Expected Value ◽  
Actual Performance ◽  
Ten Commandments ◽  
Simulation Results

Simulation designers are continuously facing the challenge of determining how much of the expected value the simulation has delivered to the client. Addressing this challenge is not easy, and it requires simulation designers to stretch their comfort zones. This article presents a ten-step approach for meeting simulation objectives and translating simulation results into actual performance improvement. Each of these ten commandments is explained and illustrated by using real-life simulation projects.

Intelligent Control Emotion Mechanism Based on Artificial Life

2014 ◽  
Vol 494-495 ◽  
pp. 1220-1224
Author(s):  
Guo Feng Zhang
Keyword(s):  
Intelligent Control ◽  
Artificial Life ◽  
Control Algorithm ◽  
Inverted Pendulum ◽  
Design Parameters ◽  
Simulation Platform ◽  
Original Algorithm ◽  
Simulation Results ◽  
Improved Algorithm

The emotion mechanism being introduced to Human-Simulated Intelligent Control algorithm, a fresh Intelligent Control algorithm is proposed, to solve the parameters design and tuning difficulty of the original algorithm. The verification of proposed control algorithm is completed on the car-inverted pendulum simulation platform. After the simulation results of the original and its improved algorithm is compared with, the new control algorithm can be found to obtain better control results with less design parameters. Thus, the suggested idea confirms its feasibility and effectiveness preliminarily.

Structural Integrity of Hydrogen Storage Tanks at Pre-Stressing and Operating Pressures

2005 ◽  
Author(s):  
J. L. Parham ◽  
Y. B. Guo ◽  
W. H. Sutton
Keyword(s):  
Hydrogen Storage ◽  
Stress Level ◽  
Structural Integrity ◽  
Real Life ◽  
Peak Stress ◽  
Operating Pressure ◽  
Middle Section ◽  
Element Analysis ◽  
Residual Strains ◽  
Simulation Results

With the fuel prices reaching record highs and ever-increasing tighter environmental policies, hydrogen-powered vehicles have great potential to substantially increase overall fuel economy, reduce vehicle emissions, and decrease dependence on foreign oil imports. While hydrogen fuel is exciting for automotive industries due to its potentials of significant technical and economic advantages, design and manufacture safe and reliable hydrogen tanks is recognized as the number one priority in hydrogen technology development and deployment. Real life testing of tank performance is extremely useful, but very time consuming, expensive, and lacks a rigorous scientific basis, which prohibits the development of a more reliable hydrogen tank. However, very few testing and simulation results can be found in public literature. This paper focused on the development of an efficient finite element analysis (FEA) tool to provide a more economical alternative for hydrogen tank analysis, though it may not be an all-out replacement for physical testing. A FEA model has been developed for the hydrogen tank with 6061-T6 aluminum liner and carbon-fiber/epoxy shell to investigate the tank integrity at pre-stresses of 45.5 MPa, 70 MPa, and 105 MPa and operating pressures of 35 MPa, 70 MPa, and 105 MPa. The residual stresses induced by different pre-stresses are at the equivalent level in the middle section but vary significantly in other tank sections. Residual stress magnitudes may saturate at a certain pre-stress level. In contrast, the residual strains in the middle section increases with pre-stress. The simulation results indicate that the optimal pre-stress level depends on the specific operating pressure to enhance tank integrity. A certain area of the neck and the top and bottom domes also experiences peak stress and strain at pre-stressing and regular operating pressures. The research findings may help manufacturing industries to build safety into manufacturing practices of hydrogen storage infrastructures.

Suppression of Sea Clutter of Skywave Radar Based on AR Model

2012 ◽  
Vol 239-240 ◽  
pp. 382-386
Author(s):  
X H Zhang ◽  
W Sheng ◽  
S H Liu
Keyword(s):  
Time Sequence ◽  
Ar Model ◽  
Original Signal ◽  
Clutter Suppression ◽  
Sea Clutter ◽  
Signal Characteristic ◽  
Forming Mechanism ◽  
First Order ◽  
Simulation Results ◽  
Suppression System

The prediction of chaotic time sequence based on AR model is studied. The forming mechanism of the first-order Bragg lines of sea clutter is analyzed. According to the signal characteristic of sea clutter, a sea clutter time sequence predictor and a skywave radar sea clutter suppression system based on AR model are presented. The cancelling of sea clutter is achieved by subtracting the predicted signal from the original signal. The simulation results show that the first-order Bragg lines in the signal were suppressed effectively after processed by this sea clutter suppression system, the detecting performance of skywave radar was increased dominatively.

Cellular Differential Evolution for Optimization

2011 ◽  
Vol 474-476 ◽  
pp. 1770-1775
Author(s):  
Gui Wu Hu ◽  
Xiao Yong Du
Keyword(s):  
Cellular Automata ◽  
Differential Evolution ◽  
Information Exchange ◽  
Cellular Structure ◽  
Mutation Operator ◽  
Solution Quality ◽  
Base Vector ◽  
Quality Stability ◽  
Simulation Results ◽  
And Diffusion

This paper is to illustrate the Cellular Differential Evolution with the cellular structure originated from Cellular automata. Cellular neighbor local search has been designed; base vector or global best in mutation operator is substituted by neighborhood-best, which overcomes the weakness of single selection relating to global best, and balances the contradiction of local and global search, and improves the diversity of population. In addition, cellular structure ensures information exchange, inheritance and diffusion. Finally, a specific algorithm has been implemented: compared with similar variants of DE, the simulation results on 9 benchmark functions demonstrate that cellular differential evolutions are provided with obvious advantages in the solution-quality, stability and speed. <b></b>

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