Large Displacement Analysis of Rectangular Orthotropic Membranes Under Stochastic Impact Loading

2016 ◽  
Vol 16 (01) ◽  
pp. 1640007 ◽  
Author(s):  
Zhou-Lian Zheng ◽  
Fa-Ming Lu ◽  
Xiao-Ting He ◽  
Jun-Yi Sun ◽  
Chuan-Xi Xie ◽  
...  
Keyword(s):  
Impact Loading ◽  
Calculation Method ◽  
Structural Engineering ◽  
Membrane Surface ◽  
Fixed Time ◽  
Mean Value ◽  
Membrane Structures ◽  
Displacement Response ◽  
Governing Differential Equation ◽  
Set Up

This paper studies the calculation method about the displacement response mean function of rectangular orthotropic membranes with four edges fixed under stochastic impact loading. We set up the nonlinear stochastic governing differential equation, solve it according to the perturbation method and the random vibration theory and obtain the displacement response mean value function of the membrane surface. Furthermore, this paper makes a random simulation test for ZZF membrane material which is commonly applied in the membrane structural engineering and obtains abundant deflection response sample curves about the feature points of the membrane surface. For sample curves statistical analysis at some fixed time, sample means can be obtained, which verify the correctness of the theoretical calculation method. The calculation method provides a theoretical basis for vibration control of building membrane structures to control the occurrence of natural disasters.

NONLINEAR DAMPED VIBRATION OF PRE-STRESSED ORTHOTROPIC MEMBRANE STRUCTURE UNDER IMPACT LOADING

2013 ◽  
Vol 14 (01) ◽  
pp. 1350055 ◽  
Author(s):  
CHANG-JIANG LIU ◽  
ZHOU-LIAN ZHENG ◽  
XIAO-YAN YANG ◽  
HUA ZHAO
Keyword(s):  
Impact Loading ◽  
Forced Vibration ◽  
Membrane Structure ◽  
Lateral Displacement ◽  
Membrane Surface ◽  
Equations Of Motion ◽  
Membrane Structures ◽  
Nonlinear Forced Vibration ◽  
Deflection Theory ◽  
Large Deflection Theory

This paper is concerned with the nonlinear damped forced vibration problem of pre-stressed orthotropic membrane structure under impact loading. The governing equations of motion were derived based on the von Kármán large deflection theory and D'Alembert's principle, and solved by using the Bubnov–Galerkin method and the Krylov–Bogolubov–Mitropolsky (KBM) perturbation method. The asymptotic analytical solutions of the frequency and lateral displacement of rectangular orthotropic membrane with fixed edges were obtained. In the computational example, the frequency results were compared and analyzed. Meanwhile, the vibration mode of the membrane and the displacement and time curves of each feature point on the membrane surface were analyzed. The results obtained herein provide a simple and convenient approach to calculate the frequency and lateral displacement of the nonlinear forced vibration of rectangular orthotropic membranes with low viscous damping under impact loading. In addition, the results provide some computational basis for the vibration control and dynamic design of membrane structures.

Study the Relative Permeability of Ferrofluid with the Mean Value Analysis of Experimental Apparent Gravity

2011 ◽  
Vol 194-196 ◽  
pp. 533-536
Author(s):  
Je Ee Ho
Keyword(s):  
Relative Permeability ◽  
Magnetic Characteristic ◽  
Physical Property ◽  
Experimental System ◽  
Mean Value ◽  
Efficient Operation ◽  
Value Analysis ◽  
Implicit Model ◽  
Drastic Increase ◽  
Set Up

Relative permeability is an important magnetic characteristic for ferrofluid to exhibit its magnetized potential during the magnetization process. To understand above physical property varying with field intensity, a popular analytic model, based on Langevin theory, has been usually considered and widely used. Unfortunately, an implicit model, derived from above hypothesis, for solving the instantaneous magnetization of ferro-particle will be carried out unless the determination of saturated magnetization should be conducted in advance. Just for the study dealing with magnetic property of testing ferro-sample is concerned, the previous acquisition of magnetization curve is impossible and unpractical without the precise measurement of magnetization-degree. On the other hand, required experimental expense is still so costly that it seems to be unaffordable for general laboratory. Thus a self-designed electromagnetic mechanism with special facility of smaller size, economical cost and efficient operation to quantify the reduced gravity of ferro-sample attracts our interest and is set up in this study. Meantime, an auxiliary numerical method, Newton interpolatory divided-difference formulas in trapezoidal rule, involved in this study successfully avoids the essentiality of saturated magnetization determined previously, and which also provides a numerical approximation through the weight loss of ferrofluid experienced by the designed experimental system. As compared with the result measured by VSM (vibration sample magnetometer) method, the estimated profile shows an excellent agreement except the extraordinary outcome occurring at B=6 mT, where a drastic increase of relative permeability will be evaluated due to the faster magnetization starts.

Research on Confidence Degree of Enterprise Alliance under the Environment of Network-Based Manufacturing

2012 ◽  
Vol 605-607 ◽  
pp. 516-520
Author(s):  
Xian Zhang
Keyword(s):  
Calculation Method ◽  
New Products ◽  
Partner Selection ◽  
Confidence Degree ◽  
Set Up ◽  
Simplified Calculation ◽  
Simplified Calculation Method

Under the environment of the network-based manufacturing, Ihe goal of the formation of enterprise alliance is to expeditiously complete the development of new products to gain the market. In order to meet the chance for enterprises alliance to complete the goal largest, this paper provided the concept of confidence degree and its corresponding calculation method. After studying the confidence degree of the total enterprise alliance, the simplified calculation method is set up for the big alliance. This calculation mathod can embody the essence of the partner selection better, and provide a rational strategy for establishing the enterprise alliance.

Evaluation of Cumulative Damage of RC Members under Repeated Impact Loading

2015 ◽  
Vol 784 ◽  
pp. 500-507 ◽  
Author(s):  
Hiroki Tamai ◽  
Yoshimi Sonoda
Keyword(s):  
Impact Loading ◽  
Structural Engineering ◽  
Damage Mechanics ◽  
Continuum Damage Mechanics ◽  
Numerical Approach ◽  
Cumulative Damage ◽  
Impact Behavior ◽  
Low Velocity ◽  
Repeated Impact ◽  
Applicability Limit

In the civil and structural engineering field, there are so many problems regarding act of impact loading against some structures due to natural disaster. So it is important to evaluate the damage condition of them after impact loading, and to estimate the residual performance of them. This study is focused on a reinforced concrete (herein after called RC) structure such as caisson breakwater and rock-shed. In order to quantitatively evaluate the dynamic behavior and cumulative damage of RC members under low-velocity single and repeated impact loading, we conducted numerical approach by using the theory of Continuum Damage Mechanics (herein after called CDM). At the result, we clarified not only impact behavior of the members but also the relationship between cumulative kinetic energy of repeated impact loading and cumulative damage of the members. In addition, applicability limit of our model based on scalar damage modeling was clarified.

Numerical Simulation of the Airliner Door under Explosion Impact Loading and Reinforcement Technique

2011 ◽  
Vol 704-705 ◽  
pp. 450-454
Author(s):  
Ying Liu ◽  
Dun Wen Zuo ◽  
Yao Hua Wang ◽  
Xin Hua Chen ◽  
Ji Xian He ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Finite Element ◽  
Impact Loading ◽  
Physical Parameters ◽  
Simplified Models ◽  
Finite Element Software ◽  
Combination Of Methods ◽  
Set Up ◽  
Reinforcement Measures ◽  
Passenger Cabin

This paper comprehensively uses a combination of methods of theoretical analysis, numerical simulation as well as the model test to do the structural analysis to some type of the passenger cabin doors, so as to set up the model for the descriptions of the part subjected to explosion impact loading; Through the tests, we gets the explosion impact loading and other important physical parameters. Aimed at the material of the door as well as the simplified models subjected to the explosion impact loading, the numerical simulation is put up by the finite element software ABAQUS. The necessity of the reinforcement is deeply analyzed as well as the difficulties during the process of the reinforcement, furthermore, the reinforcement measures are proposed to the airliner door. Keywords: Numerical simulation; Explosion impact loading; Explosion-combustion power equipments

scholarly journals L-P Perturbation Solution of Nonlinear Free Vibration of Prestressed Orthotropic Membrane in Large Amplitude

2010 ◽  
Vol 2010 ◽  
pp. 1-17 ◽  
Author(s):  
Liu Chang-jiang ◽  
Zheng Zhou-lian ◽  
He Xiao-ting ◽  
Sun Jun-yi ◽  
Song Wei-ju ◽  
...  
Keyword(s):  
Free Vibration ◽  
Large Amplitude ◽  
Lateral Displacement ◽  
Membrane Surface ◽  
Displacement Function ◽  
Governing Equations ◽  
Membrane Structures ◽  
Nonlinear Free Vibration ◽  
Time Curve ◽  
Computational Basis

This paper reviewed the research on the nonlinear free vibration of pre-stressed orthotropic membrane, which is commonly applied in building membrane structures. We applied the L-P perturbation method to solve the governing equations of large amplitude nonlinear free vibration of rectangular orthotropic membranes and obtained a simple approximate analytical solution of the frequency and displacement function of large amplitude nonlinear free vibration of rectangular membrane with four edges simply supported. By giving computational examples, we compared and analyzed the frequency results. In addition, vibration mode of the membrane and displacement and time curve of each feature point on the membrane surface were analyzed in the computational example. Results obtained from this paper provide a simple and convenient method to calculate the frequency and lateral displacement of nonlinear free vibration of rectangular orthotropic membranes in large amplitude. Meanwhile, the results provide some theoretical basis for solving the response of membrane structures under dynamic loads and provide some computational basis for the vibration control and dynamic design of building membrane structures.

scholarly journals Membrane Structures of the Hemifusion-Inducing Fusion Peptide Mutant G1S and theFusion-Blocking Mutant G1V of Influenza Virus HemagglutininSuggest a Mechanism for Pore Opening in MembraneFusion

2005 ◽  
Vol 79 (18) ◽  
pp. 12065-12076 ◽  
Author(s):  
Yinling Li ◽  
Xing Han ◽  
Alex L. Lai ◽  
John H. Bushweller ◽  
David S. Cafiso ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Membrane Fusion ◽  
Lipid Bilayer ◽  
Membrane Surface ◽  
Helical Structure ◽  
Fusion Peptide ◽  
Membrane Structures ◽  
Influenza Virus Hemagglutinin ◽  
Target Membrane ◽  
Pore Opening

ABSTRACT Influenza virus hemagglutinin (HA)-mediated membrane fusion is initiated by a conformational change that releases a V-shaped hydrophobic fusion domain, the fusion peptide, into the lipid bilayer of the target membrane. The most N-terminal residue of this domain, a glycine, is highly conserved and is particularly critical for HA function; G1S and G1V mutant HAs cause hemifusion and abolish fusion, respectively. We have determined the atomic resolution structures of the G1S and G1V mutant fusion domains in membrane environments. G1S forms a V with a disrupted “glycine edge” on its N-terminal arm and G1V adopts a slightly tilted linear helical structure in membranes. Abolishment of the kink in G1V results in reduced hydrophobic penetration of the lipid bilayer and an increased propensity to formβ -structures at the membrane surface. These results underline the functional importance of the kink in the fusion peptide and suggest a structural role for the N-terminal glycine ridge in viral membrane fusion.

scholarly journals Result interpretation of experimental calibration for milk citric acid determination via infra-red spectroscopy (MIR-FT)

2009 ◽  
Vol 57 (5) ◽  
pp. 87-102 ◽  
Author(s):  
Oto Hanuš ◽  
Irena Hulová ◽  
Václava Genčurová ◽  
Ladislav Štolc ◽  
Josef Kučera ◽  
...  
Keyword(s):  
Citric Acid ◽  
Reference Sample ◽  
Mean Value ◽  
Photometric Method ◽  
Stress Effect ◽  
Experimental Calibration ◽  
Milk Samples ◽  
Infra Red ◽  
Mean Differences ◽  
Set Up

Citric acid (KC) in milk is indicator of cow energy metabolism. Milk laboratories set up KC determination. A method can be infra-red analyse (MIR-FT). The goal was to develop a relevant method for reference sample preparation for MIR-FT (indirect method, Lactoscope FTIR and MilkoScan FT 6000) calibration. As reference was used a photometric method (c; 428 nm). KC was added (n = 3) into some re­fe­ren­ce milk samples (n = 10, bulk milk). Mean value was 9.220 ± 3.094 mmol . l−1with variation range from 6.206 to 15.975 mmol . l−1. Recovery c was from 100.8 to 120.2 %. Correlation between c and ­MIR-FT were from 0.979 to 0.992 (P < 0.001). These were lower in the set of native milk samples (n = 7), from 0.751 (Lactoscope FTIR; P < 0.05) to 0.947 (MilkoScan FT 6000; P < 0.001) in comparison to original va­lues from 0.981 to 0.992 (n = 10; P < 0.001). Correlations between calibrated MIR-FT instruments were from 0.958 to 1.0 (P < 0.001). Average recovery for instruments (n = 12) was 101.6 ± 18.1 %. The mean differences between c method and MIR-FT after calibration (n = 4) moved from −0.001 across zero to 0.037 %. Standard deviation of differences was from 0.0074 to 0.0187 % at MilkoScan FT 6000 and from 0.0105 to 0.0117 % for Lactoscope FTIR. Relative variability of differences (MIR-F (filter technology) and FT) for major components fat (T), proteins (B) and lactose (L) in total and minor components KC and free fatty acids (VMK) was estimated to 1.0 and 7.2 and 34.4 %. The KC result is inferior than T, B and L superior than VMK. Autocorrelation (0.042; P > 0.05) of results demonstrated the in­de­pen­den­ce of consecutive measurements. Milk preservation effect amounted 0.2323 (P < 0.001) with bronopol and 0.0339 (P > 0.05) mmol . l−1with dichromate. It was (3.0 and 0.44 %) practically negligible, redeemable via relevant calibration. The results of proficiency testing in post-calibration period and evaluation of double transport stress effect samples (difference was −0.006 ± 0.071 mmol . l−1(P > 0.05)) demonstrated the useability for central calibration system. Milk KC results of MIR-FT calibration were good and can be suitable for practical screening.

scholarly journals Preparation and Characterization of Various Membrane Morphologies for Lateral Flow Immunoassay Development

2017 ◽  
Vol 5 (1) ◽  
Author(s):  
A. L. Ahmad ◽  
S. C. Low ◽  
S. R. Abd Shukor ◽  
A. Ismail
Keyword(s):  
Protein Binding ◽  
Membrane Surface ◽  
Lateral Flow ◽  
Protein Quantification ◽  
Membrane Structures ◽  
Binding Ability ◽  
Membrane Pore ◽  
Pore Structures ◽  
Quantitative Understanding ◽  
Ponceau S

Lateral flow in nitrocellulose membrane is widely used as the transport medium in immunological test strips. The immunoassay performance depends greatly on the binding mechanism on membrane surface. If the membrane structures could be controlled precisely, various kinds of immunological analysis could be performed effectively and accurately. This study is aimed at a quantitative understanding on (1) the sensitivity of protein quantification on membrane surface by using densitometer and (2) comparison of the protein binding ability on different membrane surface pore structures. Concentration of immobilised protein on membrane surface was measured as a function of colour intensity, which is initially stained with Ponceau S. The findings showed that membrane morphologies significantly affect the sensitivity of membrane protein binding ability. Depending on the membrane pore structures, different red spot sharpness and intensities were observed from the stained protein dot. Membrane with smaller pore creates higher protein immobilization density and thus, increases the sensitivity level of the assay. However, larger membrane pore structure is necessary to induce rapid migration rate for faster assay.

scholarly journals Adaptive Fixed-Time Tracking Consensus Control for Multiagent Nonlinear Pure-Feedback Systems with Performance Constraints

2021 ◽  
Vol 2021 ◽  
pp. 1-23
Author(s):  
Pinwei Li ◽  
Jiyang Dai ◽  
Jin Ying
Keyword(s):  
Fixed Time ◽  
Mean Value ◽  
High Order ◽  
Mean Value Theorem ◽  
Feedback Systems ◽  
Feedback Form ◽  
Consensus Control ◽  
Performance Constraints ◽  
Whole Process ◽  
Constraint Variable

This paper investigates adaptive fixed-time tracking consensus control problems for multiagent nonlinear pure-feedback systems with performance constraints. Compared with existing results of first/second/high-order multiple agent systems, the studied systems have more complex nonlinear dynamics with each agent being modeled as a high-order pure-feedback form. The mean value theorem is introduced to address the problem of nonaffine structure in nonlinear pure-feedback systems. Meanwhile, radial basis function neural networks (RBFNNs) are employed to approximate unknown functions. Furthermore, a constraint variable is used to guarantee that all local tracking errors are within the prescribed boundaries. It is shown that, by utilizing the proposed consensus control protocol, each tracking consensus error can converge into a neighborhood around zero within designed fixed time, the tracking consensus performance can be ensured during the whole process, and all signals in the investigated systems are bounded. Finally, two simulations are performed and the results demonstrate the effectiveness of the proposed control strategy.

Sign in / Sign up

Export Citation Format

Share Document