Transmission characteristics of cylindrical frequency selective fabrics with Jerusalem-shaped units

Two kinds of complementary cylindrical frequency selective fabrics (CFSFs) with Jerusalem-shaped units were designed, constructed and analyzed in this paper. The models were built and simplified based on the thickness and equivalent electromagnetic parameters of the base fabrics. Considering the unit number difference of the models and bending directionality, the simulation processes were separately carried out using the waveguide method in HFSS software. Based on the preparation of preliminary planar prototypes and corresponding bending molds, different CFSF samples with the same planar units and varying bending curvature were fabricated, and the transmission characteristics were measured using the transmission method to study the influences of bending effects. The measured transmission characteristics with and without the curved mold were similar, proving the use of the curved mold exerted a negligible effect on the actual measured results of samples. For the two kinds of complementary structures, the measured and simulated S21 (transmission coefficient) curves had indistinguishable differences, which justified the validity of the modeling and simulation process. Although the bending direction and curvature affected the S21 curves of aperture and patch CFSFs at varying degrees, the transmission characteristics did not show drastic fluctuation and shifting, which could be attributed to the ideal symmetry of Jerusalem-shaped units and good array characteristics.

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Narrow-band frequency selective fabrics: simulation and experiment results

Textile Research Journal ◽

10.1177/0040517519832844 ◽

2019 ◽

Vol 89 (19-20) ◽

pp. 4272-4281

Author(s):

Fuwang Guan ◽

Zhaole Li ◽

Zhuli Yang ◽

Chuyang Zhang ◽

Yiping Qiu

Keyword(s):

Narrow Band ◽

Design Method ◽

Simulation Software ◽

Transmission Characteristics ◽

Transmission Method ◽

Band Frequency ◽

Simulation And Optimization ◽

Simulation And Experiment ◽

Frequency Selective ◽

High Consistency

In this paper, frequency selective fabrics (FSFs) with narrow-band transmission characteristics were proposed. The square-ring FSF was taken as an instance to illustrate the design principle. Based on the existing theoretical basis and by means of software simulation and optimization, the optimum structures with ideal narrow-band band-stop or band-pass characteristics were obtained. Then, the practical specimens were manufactured through a computer-based carving process and measured using the transmission method in an anechoic chamber. Two structural models were respectively simulated using two different algorithms and the results showed very small differences, primarily verifying the effectiveness of the design methods and reasonability of the model simplification. The measured and simulated transmission characteristics of square-ring FSFs were compared and showed a high consistency, which further verified the validation of the design method. The other two kinds of FSFs, namely Jerusalem-shaped and circle/ring hybrid FSFs, were designed and measured, which showed the narrow-band frequency selective characteristics were quite ideal. This indicates that the proposed design method using simulation software may be applied to many different structures and has directive sense in the related product design and development process.

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Modeling and Simulation of Engine Power Based on MATLAB/SIMULINK

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.875-877.929 ◽

2014 ◽

Vol 875-877 ◽

pp. 929-933 ◽

Cited By ~ 2

Author(s):

Hui Meng ◽

Li Qiang Wang ◽

Zong Qi Han ◽

Shu Bin Lei

Keyword(s):

Modeling And Simulation ◽

Bench Test ◽

Matlab Simulink ◽

Engine Modeling ◽

Simulation Process ◽

Fuel Dynamics ◽

Model Engine ◽

Output Characteristics ◽

Actual Control ◽

Engine Power

The intake system sub-model, the fuel dynamics sub-model and the power output sub-model are studied in this paper based on Elbert Hendricks engine mean model. Engine output characteristics using computational model is established in MATLAB/Simulink. Parameter of the modeling and simulation process is obtained through experiments, and finally, the engine bench test is done, and compared it with the simulation curve in same conditions. The results show that the model calculation has smaller error, higher precision, and which can meet the basic requirements of the engine modeling in actual control.

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Wave Steepness and Relative Width: Influence on Transmission Coefficient of Horizontal Interlaced, Multilayered, Moored Floating Pipe Breakwater With Five Layers

Marine Technology Society Journal ◽

10.4031/mtsj.45.5.1 ◽

2011 ◽

Vol 45 (5) ◽

pp. 20-27

Author(s):

Sacchi Rajappa ◽

Arkal Vittal Hegde ◽

Subba Rao ◽

Veena Channegowda

Keyword(s):

Physical Model ◽

Transmission Coefficient ◽

Wave Height ◽

Incident Wave ◽

Wave Attenuation ◽

Transmitted Wave ◽

Relative Width ◽

Wave Steepness ◽

Transmission Characteristics ◽

Time Period

AbstractThis paper presents the results of a series of physical model scale experiments conducted to determine the transmission characteristics of a horizontal interlaced, multilayered, moored floating pipe breakwater. The studies are conducted on physical breakwater models having five layers of PVC pipes. The wave steepness (Hi/gT2, where Hi is incident wave height, g is acceleration due to gravity, and T is time period) was varied between 0.063 and 0.849, relative width (W/L, where W is width of breakwater and L is the wavelength) was varied between 0.4 and 2.65, and relative spacing (S/D, where S is horizontal centre to centre spacing of pipes and D is the diameter of pipes) was set equal to 2. The transmitted wave height is measured, and the gathered data are analyzed by plotting nondimensional graphs depicting the variation of Kt (transmission coefficient) with Hi/gT2 for values of d/W (d is depth of water) and of Kt with W/L for values of Hi/d. It is observed that Kt decreases as Hi/gT2 increases for the range of d/W between 0.082 and 0.139. It is also observed that Kt decreases with an increase in W/L values for the range of Hi/d from 0.06 to 0.40. The maximum wave attenuation achieved with the present breakwater configuration is 78%.

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Reflection and transmission characteristics of frequency selective surface embedded within a thick plasma layer

Optik ◽

10.1016/j.ijleo.2019.163453 ◽

2020 ◽

Vol 200 ◽

pp. 163453

Author(s):

Jinzu Ji ◽

Yunpeng Ma ◽

Cong Sun

Keyword(s):

Plasma Layer ◽

Frequency Selective Surface ◽

Transmission Characteristics ◽

Reflection And Transmission ◽

Frequency Selective

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Increasing yoghurt daily production with modeling and simulation process

Ciência Rural ◽

10.1590/0103-8478cr20180187 ◽

2019 ◽

Vol 49 (1) ◽

Author(s):

Adolfo Vicente Araújo ◽

Daniel Marçal de Queiroz ◽

Gemima Santos Arcanjo ◽

Santos Henrique Brant Dias ◽

Renato Martins Alves ◽

...

Keyword(s):

Computer Simulation ◽

Modeling And Simulation ◽

Production Capacity ◽

Simulation Software ◽

Decision Makers ◽

Productive Capacity ◽

Daily Production ◽

Production Sector ◽

Simulation Process ◽

Current Production

ABSTRACT: The objective of this research was to use the modeling and computer simulation to support decision makers, aiming to increase the productive capacity of the agro-industry of LaticínioFunarbe. Specifically, it has modeled the current yoghurt production sector for simulation that enables it to meet the new demand. The Arena 14.7 simulation software was used to conduct the modeling. To validate the model, the output of yoghurt production collected at the factory for three months was compared with the output from the simulated computational model. Two indicators were established to perform analyzes of four different scenarios. The implemented model resulted in an increase in the production capacity of 5,000L.d-1 of yoghurt, corresponding to a production of yoghurts processed daily three times higher than the current production.

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