Damage detection technique for irregular continuum structures using wavelet transform and fuzzy inference system optimized by particle swarm optimization

Hamidian, Davood,Salajegheh, Eysa,Salajegheh, Javad Techno-Press 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.67 No.5

This paper presents a method for detecting damage in irregular 2D and 3D continuum structures based on combination of wavelet transform (WT) with fuzzy inference system (FIS) and particle swarm optimization (PSO). Many damage detection methods study regular structures. This method studies irregular structures and doesn't need response of healthy structures. First the damaged structure is analyzed with finite element methods, and damage response is obtained at the finite element points that have irregular distance, secondly the FIS, which is optimized by PSO is used to obtain responses at points, having equal distance by response at those points that previously obtained by the finite element methods. Then a 2D (for 2D continuum structures) or a 3D (for 3D continuum structures) matrix is performed by equal distance point response. Thirdly, by applying 2D or 3D wavelet transform on 2D or 3D matrix that previously obtained by FIS detail matrix coefficient of WT is obtained. It is shown that detail matrix coefficient can determine the damage zone of the structure by perturbation in the damaged area. In order to illustrate the capability of proposed method some examples are considered.

The effect of vitamin C on the gene expression profile of sperm protamines in the male partners of couples with recurrent pregnancy loss: A randomized clinical trial

Hamidian, Saeideh,Talebi, Ali Reza,Fesahat, Farzaneh,Bayat, Mohammad,Mirjalili, Ali Mohammad,Ashrafzadeh, Hamid Reza,Rajabi, Mahya,Montazeri, Fateme,Babaei, Saeid The Korean Society for Reproductive Medicine 2020 Clinical and Experimental Reproductive Medicine Vol.47 No.1

Objective: Since sperm abnormalities are known to be a major reason for recurrent pregnancy loss (RPL), any defects in DNA structure and chromatin condensation can place embryos at risk in the early stage of development and implantation. As antioxidants such as vitamin C may play a protective role against the destruction of protamine genes in sperm chromatin, this study was conducted to evaluate the effects of vitamin C on chromatin and the expression of protamine genes in the male partners of couples with RPL. Methods: Twenty male partners of couples with RPL were selected as the intervention group and received vitamin C supplementation (250 mg daily for 3 months). Healthy fertile men (n = 20) were included as controls. Sperm chromatin, DNA integrity, and the expression levels of protamine genes were evaluated before and after treatment. Results: Significant differences were found in sperm morphology, protamine deficiency, and apoptosis between the two groups and before and after vitamin C administration. A significant change was found in mRNA levels of PRM1, PRM2, and the PRM1/PRM2 ratio after treatment. Conclusion: Daily oral administration of vitamin C may improve human sperm parameters and DNA integrity by increasing protamine gene expression levels in the male partners of couples with RPL. The beneficial effects of vitamin C supplementation as an antioxidant for the male partners of couples with RPL could lead to improved pregnancy outcomes in these cases.

Detection of a Cooper-pair density wave in Bi₂Sr₂CaCu₂O_8+x

Hamidian, M. H.,Edkins, S. D.,Joo, Sang Hyun,Kostin, A.,Eisaki, H.,Uchida, S.,Lawler, M. J.,Kim, E.-A.,Mackenzie, A. P.,Fujita, K.,Lee, Jinho,Davis, J. C. Sé,amus Nature Publishing Group, a division of Macmillan P 2016 Nature Vol.532 No.7599

<P>The quantum condensate of Cooper pairs forming a superconductor was originally conceived as being translationally invariant. In theory, however, pairs can exist with finite momentum Q, thus generating a state with a spatially modulated Cooper-pair density(1,2). Such a state has been created in ultracold Li-6 gas(3) but never observed directly in any superconductor. It is now widely hypothesized that the pseudogap phase(4) of the copper oxide superconductors contains such a 'pair density wave' state(5-21). Here we report the use of nanometre-resolution scanned Josephson tunnelling microscopy(22-24) to image Cooper pair tunnelling from a d-wave superconducting microscope tip to the condensate of the superconductor Bi2Sr2CaCu2O8+x. We demonstrate condensate visualization capabilities directly by using the Cooper-pair density variations surrounding zinc impurity atoms(25) and at the Bi2Sr2CaCu2O8+x crystal supermodulation(26). Then, by using Fourier analysis of scanned Josephson tunnelling images, we discover the direct signature of a Cooper-pair density modulation at wavevectors Q(P) approximate to (0.25, 0)2 pi/a(0) and (0, 0.25)2 pi/a(0) in Bi2Sr2CaCu2O8+x. The amplitude of these modulations is about five per cent of the background condensate density and their form factor exhibits primarily s or s' symmetry. This phenomenology is consistent with Ginzburg-Landau theory(5,13,14) when a charge density wave(5,27) with d-symmetry form factor(28-30) and wavevector Q(C) = Q(P) coexists with a d-symmetry superconductor; it is also predicted by several contemporary microscopic theories for the pseudogap phase(18-21).</P>

Fatigue life enhancement of automobile wheel disc considering multi-axial stresses based on critical plane approach

Homayoon Hamidian,Abdollah Tavakoli Lahijani,Shahram Shahriari 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.6

We report an optimization procedure of automobile steel wheel fatigue life enhancement considering multi axial stresses based oncritical plane approach via Design of experiments (DOE), Response surface methodology (RSM) and reflective Newton methodology. The wheel disc stiffener shape was optimized by defining seven parameters of the stiffener shape (design factors). Central compositedesign of experiments theory was used to select a minimum but sufficient combination of the design factors, FEM analysis was used tocompute the stresses in the disc wheel under cornering load for each design factor combination. To verify the FEM modeling, we conductedan experimental fatigue test. The stress components variation for any arbitrary direction of loading were estimated and the multiaxial fatigue and critical plane approach were used to evaluate the margin to fatigue damage. We found that stress components for onlythree radial loading directions of the rotating force are required to obtain sufficiently accurate stress histories at critical point and criticaldirection. A clear method was introduced regarding the correct shear stress range selection on critical plane. The RSM, a quadratic surface,was fitted to analytical results regarding the mentioned models. To verify the accuracy of the fitted surface, the responses at thedesign factors combinations were calculated via the identified quadratic model and compared to the FEM analysis results. Optimumvalue of design factors was obtained through reflective Newton method which led to generation of the refined wheel stiffener shape. Theproposed method for determining the stress components could be used in any similar rotating parts such as wheel hub, brake disc, brakedrum, etc.

Irregular Continuum Structures Damage Detection based on Wavelet Transform and Neural Network

Davood Hamidian,Eysa Salajegheh,Javad Salajegheh 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.11

This paper presents a method for detecting damage in irregular 2D and 3D continuum structures based on combination of wavelet with neural network. The method proposed here only requires the responses (displacements, stresses) of the damaged structures, while most damage detection methods need the structural responses before and after damage. First, the structural responses related to the damaged state are determined at the finite element points having irregular distances. Secondly, the Multiple-Layer Perceptron Neural Network (MLPNN) is used to estimate the responses at points having equal distances by those previously obtained by the finite element. Then, the extended responses are analyzed with the 2D and 3D wavelet transform in order to locate damaged zones. It is shown that detailed matrix coefficients of 2D and 3D wavelet transform can identify the damaged zone of the structure by perturbation in the damaged area. In order to assess the performance of the proposed method, some numerical examples are considered. The results show the high efficiency of the method for damage localization of the structure.

Damage detection technique for irregular continuum structures using wavelet transform and fuzzy inference systemoptimized by particle swarm optimization

Davood Hamidian,Eysa Salajegheh,Javad Salajegheh 국제구조공학회 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.67 No.5

This paper presents a method for detecting damage in irregular 2D and 3D continuum structures based on combination of wavelet transform (WT) with fuzzy inference system (FIS) and particle swarm optimization (PSO). Many damage detection methods study regular structures. This method studies irregular structures and doesn’t need response of healthy structures. First the damaged structure is analyzed with finite element methods, and damage response is obtained at the finite element points that have irregular distance, secondly the FIS, which is optimized by PSO is used to obtain responses at points, having equal distance by response at those points that previously obtained by the finite element methods. Then a 2D (for 2D continuum structures) or a 3D (for 3D continuum structures) matrix is performed by equal distance point response. Thirdly, by applying 2D or 3D wavelet transform on 2D or 3D matrix that previously obtained by FIS detail matrix coefficient of WT is obtained. It is shown that detail matrix coefficient can determine the damage zone of the structure by perturbation in the damaged area. In order to illustrate the capability of proposed method some examples are considered.

Detection of a pair density wave state in Bi₂Sr₂CaCu₂O<SUB>8+x</SUB> using scanned josephson tunneling

M. H. HAMIDIAN,S. D. EDKINS,Sang Hyun JOO,A. KOSTIN,S. UCHIDA,M. J. LAWLER,E. -A. KIM,A. P. MACKENZIE,K. FUJITA,Jinho LEE,J. C. DAVIS 한국진공학회 2016 한국진공학회 학술발표회초록집 Vol.2016 No.8

Post-peak Behaviour of Composite Column Using a Ductile Lightweight Aggregate Concrete

Mohammad Reza Hamidian,Payam Shafigh 한국콘크리트학회 2021 International Journal of Concrete Structures and M Vol.15 No.3

Oil palm shell (OPS) concrete filled steel tube (CFT) columns are acknowledged to be a new type of sustainable composite column. In this type of column, the conventional coarse aggregate was partially replaced with OPS lightweight aggregate to provide a green composite column. This type of CFT column showed higher energy absorption and flexibility compared to CFT columns with normal weight concrete. This research studied the effect of the strength of OPS concrete on the axial compressive behaviour of CFT columns for two grades of OPS concretes. The behaviour was comparable to that of CFT columns with two grades of normal concrete. The results showed that the CFT columns with OPS concrete achieved a new post-peak behaviour. The experimental results of the axial compressive load were compared with the estimation of two international standards. EC4-1994 and ACI318-14 showed a reliable and conservative estimation of the axial load capacity of CFT columns, respectively.

Metal Concentrations in the Coastal Fauna of the Caspian Sea

Mirzajani Alireza,Hamidian Amir Hossein,Hassan Jalal 한국해양과학기술원 2021 Ocean science journal Vol.56 No.3

Metal concentrations were measured in predominant coastal fauna of the Caspian Sea including six macro-invertebrates (Mnemiposis leidyi, Balanus improvisus, Pontogammarus maeoticus, Palaemon adspersus, Cerastoderma glucaum and Adacna vitrea) and three species of small fish (Atherina caspia, Neogobius caspius and N. pallasi) to determine potential bio-indicators (for the first time to our knowledge). It is to be noted that metal concentrations have also never been reported in M. leidyi and A. vitrea. The lowest levels of metal were observed in muscles of fishes. Most of metals were detectable in the macro-plankton M. leidyi suggesting that this species could be used for water pollution monitoring, worldwide. Our results suggest the use of C. glucaum and A. vitrea as indicators of Ni and Cd contamination, respectively. B. improvisus has a high potential as an indicator for Zn and Cu pollution, while P. adspersus and P. maeoticus showed this capacity for Cu. This study provides a baseline for biomonitoring programs elsewhere in the Caspian Sea. Furthermore, the species C. glucaum and B. improvisus could be used for comparisons of metal contamination worldwide.

A novel and reusable sensing platform for electrochemical detection of norepinephrine based on nitrogen‑doped porous carbon anchored CoFe2O4@ NiO nanocomposite

Reza Mostafazadeh,Yasamin Hamidian,Nevin Erk,Elena Niculina Dragoi 한국탄소학회 2023 Carbon Letters Vol.33 No.6

In this work, norepinephrine (NE) was determined by an electrochemical sensor represented by a carbon paste electrode boosted using nitrogen-doped porous carbon (NDPC) derived from Spirulina Platensis microalga anchored CoFe2O4@ NiO and 1-Ethyl-3-methylimidazolium acetate (EMIM Ac) ionic liquid. The morphological characteristics of the catalyst were recorded by field emission scanning electron microscope (FE-SEM) images. Moreover, the electrochemical behavior of norepinephrine on the fabricated electrode was checked using various voltammetric methods. All tests were done at pH 7.0 as the optimized condition in phosphate buffer solution. The results from linear sweep voltammetry revealed that the electro-oxidation of norepinephrine was diffusion, and the diffusion coefficient value was obtained by chronoamperometry (D⁓6.195 × 10– 4). The linear concentration of the modified electrode was obtained from 10 to 500 μM with a limit of detection of 2.26 μM using the square wave voltammetry (SWV) method. The sensor selectivity was investigated using various species, and the results from stability and reproducibility tests showed acceptable values. The sensor's efficiency was tested in urine and pharmaceutical as real samples with recovery percentages between 97.1% and 102.82%.