Air permeability of polyester nonwoven fabrics

Abstract Air permeability is one of the most important properties of non-woven fabrics in many applications. This paper aims to investigate the effects of thickness, porosity and density on the air permeability of needle-punched non-woven fabrics and compare the experimental values with two models which are based on hydraulic radius theory and drag theory, respectively. The air permeability of the samples was measured by an air permeability tester FX3300. The results showed that the air permeability of non-woven fabrics decreased with the increase in thickness and density of samples, increased with the increase of porosity, and the air permeability was not directly proportional to the pressure gradient. Meanwhile, the prediction model based on hydraulic radius theory had a better agreement with experimental values than the model based on drag theory, but the values were much higher than the experimental results, especially for higher porosity and higher pressure gradient.

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G(1,1,λ,ρ) Optimization Model and Application Based on the FS

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.644-650.1494 ◽

2014 ◽

Vol 644-650 ◽

pp. 1494-1497

Author(s):

Han Lin Wang ◽

Zi Hui Ren ◽

Li Xia Xue ◽

Yan Li Luo

Keyword(s):

Prediction Model ◽

Optimization Model ◽

Experimental Results ◽

Grey Prediction ◽

Grey Prediction Model ◽

Model Based

A grey prediction model based on Free Searching (FS) () is proposed in this paper. Firstly, FS is applied to optimize the parameters of the model. The convergence of the FS algorithm is proved in order to show the reasonable of optimization with FS. Then, we give the factors which affect the precision of the prediction by analyzing the model. Based on this, the initial array is transformed. Finally, we predict several times used model and obtain the average of the prediction results’ combination. The experimental results show that the model is feasible, reasonable and effective.

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The Effect of Singeing Calendering Processing on Properties of Filter Needled Nonwoven Fabrics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.864-867.605 ◽

2013 ◽

Vol 864-867 ◽

pp. 605-612

Author(s):

Xin Cui ◽

Wei Min Xiao ◽

Qin Fei Ke

Keyword(s):

Nonwoven Fabric ◽

Air Permeability ◽

Woven Fabrics ◽

Nonwoven Fabrics

To improve the quality of needled nonwoven for filtration, many companies will finish the nonwoven fabric in order to improve its performance. The process of singeing with calendering finishing is very important to improve its performance, after finishing the internal filter to a certain extent been blocked, reducing the pressure when cleaning, thereby extending the life of fabrics. We used different methods to deal with needle non-woven fabrics for filtration, which including singeing and singeing with calendering. Then we tested the strength, air permeability, weight and other properties of untreated samples, only singeing samples and singeing with calendering samples. The paper analyzed how treatments affect the properties of needle non-woven fabrics for filtration.

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Spreading Predictability in Complex Networks

10.21203/rs.3.rs-132928/v1 ◽

2021 ◽

Author(s):

Na Zhao ◽

Jian Wang ◽

Yong Yu ◽

Junyan Zhao ◽

Duanbing Chen

Keyword(s):

Infectious Diseases ◽

Prediction Model ◽

Complex Networks ◽

State Of The Art ◽

Experimental Results ◽

Vaccination Strategies ◽

Model Based ◽

The Future ◽

Rumor Control

Abstract Many state-of-the-art researches focus on predicting infection scale or threshold in infectious diseases or rumor and give the vaccination strategies correspondingly. In these works, most of them assume that the infected probability and initially infected individuals are known at the very beginning. Generally, infectious diseases or rumor has been spreading for some time when it is noticed. How to predict which individuals will be infected in the future only by knowing the current snapshot becomes a key issue in infectious diseases or rumor control. In this paper, a prediction model based on snapshot is presented to predict the potentially infected individuals in the future. Experimental results on synthetic and real networks demonstrate that the predicted infected individuals have rather consistency with the actual infected ones.

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The determination of air-permeability of soils.

Netherlands Journal of Agricultural Science ◽

10.18174/njas.v8i2.17653 ◽

1960 ◽

Vol 8 (2) ◽

pp. 124-131 ◽

Cited By ~ 2

Author(s):

A.R.P. Janse ◽

G.H. Bolt

Keyword(s):

Pressure Gradient ◽

Sandy Soil ◽

Constant Pressure ◽

Air Permeability ◽

Experimental Results

An improved apparatus for determining air-permeability of soils at constant pressure gradient is described; its merits are discussed in the light of existing literature. Some experimental results obtained with a sandy soil under different tillage conditions are given and discussed. (Abstract retrieved from CAB Abstracts by CABI’s permission)

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Evaluation of missile electromagnetic launch system based on effectiveness

Journal of Intelligent & Fuzzy Systems ◽

10.3233/jifs-210353 ◽

2021 ◽

pp. 1-10

Author(s):

Qiaoyang Li ◽

Guiming Chen ◽

Ziqi Li ◽

Yi Zhang ◽

Lingliang Xu

Keyword(s):

Prediction Model ◽

Environmental Pollution ◽

Infrared Radiation ◽

Experimental Results ◽

Investment Efficiency ◽

Model Based ◽

Electromagnetic Launch ◽

Effectiveness Prediction

To solve the problems of strong infrared radiation, poor continuous combat capability of the system, serious ablation of the launching device, and environmental pollution of the existing missile launching system, electromagnetic launch system (EMLS) has been studied for missile launch system. Combining the situation that the current research on missile electromagnetic launch system (MEMLS) mainly focuses on the key technical points and the deficiencies in the previous research on MEMLS, this paper establishes an effectiveness prediction model based on GRA-PCA-LSSVM, and discusses the investment efficiency of the system based on DEA. The experimental results prove that the established model is reasonable, effective and superior, and provides a reference for the further improvement and development of MEMLS.

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