Analysis of Active Deception Jamming Model against SAR

2014 ◽  
Vol 926-930 ◽  
pp. 2982-2985
Author(s):  
Rui Hui Peng ◽  
Yong Sheng Lv ◽  
Xiang Wei Wang ◽  
Ying Qian Gao
Keyword(s):  
Necessary Conditions ◽  
Signal Transmission ◽  
Time Varying ◽  
Modified Model ◽  
Basic Model ◽  
False Target ◽  
False Signal ◽  
Transmission Schedule ◽  
Schedule Time

The limitations of basic active deception jamming model against SAR reconnaissance were analyzed detailed, and the necessary conditions of false target deployment for the model were derived. Some modifications and adjustment of the basic model were made, for which target-centric signal transmission schedule was proposed instead of jammer-centric schedule, time-varying repetition delay and time-varying Doppler parameters of false signal were made instead fixed parameters. The modified model extended false target’s displacement and improved the fidelity of false target. And some calculation examples and discussions were done in the end.

scholarly journals Enhancement of Exit Flow Uniformity by Modifying the Shape of a Gas Torch to Obtain a Uniform Temperature Distribution on a Steel Plate during Preheating

2018 ◽  
Vol 8 (11) ◽  
pp. 2197
Author(s):  
Thien Ngo ◽  
Junho Go ◽  
Tianjun Zhou ◽  
Hap Nguyen ◽  
Geun Lee
Keyword(s):  
Temperature Distribution ◽  
Temperature Difference ◽  
Steel Plate ◽  
Flow Distribution ◽  
Uniform Temperature ◽  
Flow Uniformity ◽  
Modified Model ◽  
Uniform Temperature Distribution ◽  
Basic Model ◽  
New Models

The objective of this study is to improve the exit flow uniformity of a gas torch with multiple exit holes for effective heating of a steel plate. The torch was simulated, and combustion experiments were performed for validation. Based on a basic model, three different revised models were designed and analyzed with the software ANSYS FLUENT 18.2. The flow uniformity (γ) of the velocity distribution at the multiple exit holes was investigated with the pressure drop ranging from 100 to 500 Pa. The basic model had flow uniformity ranging from 0.849 to 0.852, but the three new models had γ1 = 0.901–0.912, γ2 = 0.902–0.911, and γ3 = 0.901–0.914, respectively. The maximum percentage difference of the flow uniformity index between the three new models and the basic model was 7.3%. The basic model with nonuniform flow distribution made a temperature difference of the back side of the steel plate from the center to the edge of around 229 °C, while the modified model with uniform flow distribution had a smaller temperature difference of 90 °C. The simulation results showed good agreement with our experimental results for both the basic model and the modified model. The modified gas torch made a wider and more uniform temperature distribution on a preheated steel plate than the basic one. The results revealed that a trade-off between cost and flow uniformity, as well as the new gas torch, could be applied to a steel-plate preheating process before welding.

scholarly journals Necessary Conditions for Reliable Propagation of Slowly Time-Varying Firing Rate

2020 ◽  
Vol 14 ◽  
Author(s):  
Navid Hasanzadeh ◽  
Mohammadreza Rezaei ◽  
Sayan Faraz ◽  
Milos R. Popovic ◽  
Milad Lankarany
Keyword(s):  
Firing Rate ◽  
Necessary Conditions ◽  
Time Varying

Ultimate Boundedness of Stochastic Neural Networks with Delays

2011 ◽  
Vol 204-210 ◽  
pp. 1549-1552
Author(s):  
Li Wan ◽  
Qing Hua Zhou
Keyword(s):  
Neural Networks ◽  
Linear Matrix Inequality ◽  
Lyapunov Functional ◽  
Signal Transmission ◽  
Sufficient Conditions ◽  
Linear Matrix ◽  
Stochastic Neural Networks ◽  
Time Varying ◽  
Matrix Inequality ◽  
Ultimate Boundedness

Although ultimate boundedness of several classes of neural networks with constant delays was studied by some researchers, the inherent randomness associated with signal transmission was not taken account into these networks. At present, few authors study ultimate boundedness of stochastic neural networks and no related papers are reported. In this paper, by using Lyapunov functional and linear matrix inequality, some sufficient conditions ensuring the ultimate boundedness of stochastic neural networks with time-varying delays are established. Our criteria are easily tested by Matlab LMI Toolbox. One example is given to demonstrate our criteria.

scholarly journals Mathematical Modeling and Optimal Control Analysis of COVID-19 in Ethiopia

2020 ◽  
Author(s):  
Haileyesus Tessema Alemneh ◽  
Getachew Teshome Telahun
Keyword(s):  
Optimal Control ◽  
Necessary Conditions ◽  
Reproduction Number ◽  
Control Strategies ◽  
Equilibrium Points ◽  
Control Model ◽  
Control Analysis ◽  
Basic Model ◽  
Short Period ◽  
Disease Free

In this paper we developed a deterministic mathematical model of the pandemic COVID-19 transmission in Ethiopia, which allows transmission by exposed humans. We proposed an SEIR model using system of ordinary differential equations. First the major qualitative analysis, like the disease free equilibruim point, endemic equilibruim point, basic reproduction number, stability analysis of equilibrium points and sensitivity analysis was rigorously analysed. Second, we introduced time dependent controls to the basic model and extended to an optimal control model of the disease. We then analysed using Pontryagins Maximum Principle to derive necessary conditions for the optimal control of the pandemic. The numerical simulation indicated that, an integrated strategy effective in controling the epidemic and the gvernment must apply all control strategies in combating COVID-19 at short period of time.

scholarly journals Robust Protocol-Based ℋ∞ Consensus Control of Time-Varying Uncertain Multiagent Systems Subject to Missing Measurements

Complexity ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-13
Author(s):  
Mengmeng Sun ◽  
Dongyan Chen
Keyword(s):  
Multiagent Systems ◽  
Controller Design ◽  
Signal Transmission ◽  
Sufficient Conditions ◽  
Random Variables ◽  
Time Varying ◽  
Missing Measurements ◽  
Consensus Control ◽  
Consensus Criterion ◽  
Analysis Methodology

In this paper, we consider the design problem of a robust ℋ∞ consensus controller for discrete time-varying uncertain multiagent systems (DTVUMASs) with stochastic communication protocol (SCP) and missing measurements. The SCP is described by a set of random variables with a known probability to arrange signal transmission of addressed multiagent systems. Moreover, we depict the missing measurement phenomenon by a sequence of Bernoulli-distributed random variables having known probabilities. The controller parameters are designed to ensure that the closed-loop DTVUMASs satisfy the ℋ∞ performance with the satisfactory consensus criterion. Together with the completing squares approach and the stochastic analysis methodology, some sufficient conditions are proposed by solving coupled backward recursive Riccati difference equations (BRRDEs) to guarantee the ℋ∞ consensus performance. Finally, we present a numerical simulation example to illustrate the effectiveness of the designed controller design scheme.

Adaptive Signal Detection for Statistical Signal Transmission in Fast Time-Varying Channels

2017 ◽  
Vol 66 (12) ◽  
pp. 11070-11085 ◽  
Author(s):  
Tianheng Xu ◽  
Mengying Zhang ◽  
Sha Yao ◽  
Honglin Hu ◽  
Hsiao-Hwa Chen
Keyword(s):  
Signal Detection ◽  
Signal Transmission ◽  
Fast Time ◽  
Time Varying ◽  
Adaptive Signal Detection ◽  
Adaptive Signal ◽  
Time Varying Channels

Normal Mode Uncoupling of Systems with Time Varying Stiffness

1980 ◽  
Vol 102 (2) ◽  
pp. 379-383 ◽  
Author(s):  
M. Benton ◽  
A. Seireg
Keyword(s):  
Approximate Method ◽  
Normal Mode ◽  
High Speed ◽  
Degrees Of Freedom ◽  
Necessary Conditions ◽  
Coupled Systems ◽  
Time Varying ◽  
Parametric Vibrations ◽  
Gear Trains ◽  
The Stability

This paper investigates the conditions for transforming coupled systems with time-varying stiffness to normal mode coordinates. The stability regions are determined from the normal mode equations and the effect of model damping on the width of these regions is investigated. An approximate method for uncoupling is also presented which can be used to give good practical solutions in situations where the theoretical necessary conditions are not met. The proposed method can provide a simple and effective tool for the analysis of parametric vibrations for systems with any number of degrees of freedom as in the case of high speed gear trains.

scholarly journals International Real Estate Review

2015 ◽  
Vol 18 (3) ◽  
pp. 303-316
Author(s):  
Gaetano Lisi ◽  
Keyword(s):  
Real Estate ◽  
Theoretical Result ◽  
Empirical Evidence ◽  
Direct Relationship ◽  
Hedonic Prices ◽  
Modified Model ◽  
Basic Model ◽  
Income Data ◽  
Capitalization Rate

In this paper, a model of income capitalization is developed where hedonic prices play a key role in estimating the going-in capitalization rate. Precisely, the hedonic functions for rental and selling prices are introduced into a basic model of income capitalization. From the modified model, it is possible to derive a direct relationship between hedonic prices and capitalization rate. An advantage of the proposed approach is that estimation of the capitalization rate can be made without considering rental income data. Empirical evidence is provided for the theoretical result.

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