Optimal placement of piezoelectric actuator/senor patches pair in sandwich plate by improved genetic algorithm

Amir Amini,Mehdi Mohammadimehr,Alireza Faraji 국제구조공학회 2020 Smart Structures and Systems, An International Jou Vol.26 No.6

The present study investigates the employing of piezoelectric patches in active control of a sandwich plate. Indeed, the active control and optimal patch distribution on this structure are presented together. A sandwich plate with honeycomb core and composite reinforced by carbon nanotubes in facesheet layers is considered so that the optimum position of actuator/sensor patches pair is guaranteed to suppress the vibration of sandwich structures. The sandwich panel consists of a search space which is a square of 200 × 200 mm with a numerous number of candidates for the optimum position. Also, different dimension of square and rectangular plates to obtain the optimal placement of piezoelectric actuator/senor patches pair is considered. Based on genetic algorithm and LQR, the optimum position of patches and fitness function is determined, respectively. The present study reveals that the efficiency and performance of LQR control is affected by the optimal placement of the actuator/sensor patches pair to a large extent. It is also shown that an intelligent selection of the parent, repeated genes filtering, and 80% crossover and 20% mutation would increase the convergence of the algorithm. It is noted that a fitness function is achieved by collection actuator/sensor patches pair cost functions in the same position (controllability). It is worth mentioning that the study of the optimal location of actuator/sensor patches pair is carried out for different boundary conditions of a sandwich plate such as simply supported and clamped boundary conditions.

Active control to reduce the vibration amplitude of the solar honeycomb sandwich panels with CNTRC facesheets using piezoelectric patch sensor and actuator

Amir Amini,M. Mohammadimehr,A.R. Faraji 국제구조공학회 2019 Steel and Composite Structures, An International J Vol.32 No.5

Active control of solar panels with honeycomb core and carbon nanotube reinforced composite (CNTRC) facesheets for smart structures using piezoelectric patch sensor and actuator to reduce the amplitude of vibration is a lack of the previous study and it is the novelty of this research. Of active control elements are piezoelectric patches which act as sensors and actuators in many systems. Their low power consumption is worth mentioning. Thus, deriving a simple and efficient model of piezoelectric patch’s elastic, electrical, and elastoelectric properties would be of much significance. In the present study, first, to reduce vibrations in composite plates reinforced by carbon nanotubes, motion equations were obtained by the extended rule of mixture. Second, to simulate the equations of the system, up to 36 mode shape vectors were considered so that the stress strain behavior of the panel and extent of displacement are thoroughly evaluated. Then, to have a more acceptable analysis, the effects of external disturbances (Aerodynamic forces) and lumped mass are investigated on the stability of the system. Finally, elastoelectric effects are examined in piezoelectric patches. The results of the present research can be used for micro-vibration suppression in satellites such as solar panels, space telescopes, and interferometers and also to optimize active control panel for various applications.

An investigation on the improvement of neutron radiography system of the Tehran research reactor by using MCNPX simulations

Amini, Moharram,Zamzamian, Seyed Mehrdad,Fadaei, Amir Hossein,Gharib, Morteza,Feghhi, Seyed Amir Hosein Korean Nuclear Society 2021 Nuclear Engineering and Technology Vol.53 No.10

Applying the available neutron flux for medical and industrial purposes is the most important application of research reactors. The neutron radiography system is used for non-destructive testing (NDT) of materials so that it is one of the main applications of nuclear research reactors. One of these research reactors is the 5 MW pool-type light water research reactor of Tehran (TRR). This work aims to investigate on materials and location of the beam tube (BT) of the TRR radiography system to improve the index parameters of BT. Our results showed that a through-type BT with 20 cm thick carbon neutron filter, 1.2 cm and 9.4 cm of the diameter of inlet (D₁) and output (D₂) BT, respectively gives thermal neutron flux almost 25.7, 5.6 and 1.1 times greater than the former design of the TRR (with D₁ = 1.8 cm and D₁ = 9.4 cm), previous design of the TRR with D₁ = 3 cm and D₁ = 9.4 cm, and another design with D₁ = 5 cm and D₁ = 9.4 cm, respectively. Therefore, the design proposed in this paper could be a better alternative to the current BT of the TRR.

Assessment of Iranian wheat germplasm for salinity tolerance using analysis of the membership function value of salinity tolerance (MFVS)

Gholizadeh Amir,Dehghani Hamid,Akbarpour Omidali,Amini Ashkboos,Sadeghi Kaveh,Hanifei Mehrdad,Sharifi-Zagheh Aram 한국작물학회 2022 Journal of crop science and biotechnology Vol.25 No.5

In this study, 17 morphological and agronomic traits as indicators for identifying salinity tolerance genotypes in wheat were evaluated among a set of 110 different genotypes including advanced lines in breeding programs, wheat landraces collected from landraces throughout Iran, some well-known tolerant and sensitive cultivars and many commercial wheat cultivars. Plant materials were grown under non-saline (NS) and saline stress (SS) conditions (Electrical conductivity [EC] of 2 and 10 ds m -1 , respectively). The membership function value of salinity tolerance (MFVS) was used as a comprehensive index for evaluation and selection of wheat salinity tolerance. A comprehensive evaluation method, the membership function value of salinity tolerance (MFVS), which combined the salinity-tolerant coefficient (SC) of morphological and agronomic traits that could be easily estimated, was used to investigate the wheat salinity tolerance in this study. The mean value of all 17 traits decreased under saline stress condition, among the 17 traits, spike weight (SW), kernel weight per spike (KWS), number of fertile tillers (NFT), biological yield (BY) and grain yield (GY) decreased >25%. This suggested that these 5 traits were more sensitive to salinity stress. Ten genotypes with highly salinity tolerance were selected based on MFVS and could be applied for salinity tolerance improvement in wheat. Correlation analysis indicated that the wheat salinity tolerance was highly significantly and positively correlated with variations of 13 traits under both non-saline and saline stress conditions (P < 0.01). Factor analysis showed that salinity-tolerant coefficients of 5 traits of grain yield, biological yield, spike weight, kernel weight per spike and number of fertile tillers have the most interrelationships with the membership value of salinity tolerance (MFVS). Therefore, these five traits could be applied as an indicator to screen wheat germplasm for salinity tolerance in wheat breeding programs.

Creeping flow of Herschel-Bulkley fluids in collapsible channels: A numerical study

Ali Amini,Amir Saman Eghtesad,Kayvan Sadeghy 한국유변학회 2016 Korea-Australia rheology journal Vol.28 No.4

In this paper, the steady flow of a viscoplastic fluid is modeled in a planar channel equipped with a deformable segment in the middle of an otherwise rigid plate. The fluid is assumed to obey the Herschel-Bulkley model which accounts for both the yield stress and the shear-thinning behavior of physiological fluids such as blood. To accommodate the large deformations of the flexible segment, it is assumed to obey the twoparameter Mooney-Rivlin hyperelastic model. The so-called fluid-structure interaction problem is then solved numerically, under creeping-flow conditions, using the finite element package, COMSOL. It is found that the yield stress leads to a larger wall deformation and a higher pressure drop as compared with Newtonian fluids. This behavior is predicted to intensify if the fluid is shear-thinning. That is, for a given yield stress, the pressure drop and the wall deformation both increase with an increase in the degree of the fluid's shear-thinning behavior.

Development of a $^{68}Ga$-Fluorinated Porphyrin Complex as a Possible PET Imaging Agent

Fazaeli, Yousef,Jalilian, Amir R.,Amini, Mostafa M.,Ardaneh, Khosro,Rahiminejad, Ali,Bolourinovin, Fatemeh,Moradkhani, Sedigheh,Majdabadi, Abbas The Korea Society of Nuclear Medicine 2012 핵의학 분자영상 Vol.46 No.1

Aim Due to the interesting pharmacologic properties of porphyrins, the idea of developing a possible tumor imaging agent using PET by incorporating $^{68}Ga$ into a suitable porphyrin ligand was investigated. Methods $^{68}Ga$-labeled 5,10,15,20-tetrakis(pentafluoro-13 phenyl) porphyrin ($^{68}Ga$-TFPP) was prepared using freshly eluted $[^{68}Ga]GaCl_3$ obtained from a 68Ge/68Ga generator developed in-house and 5,10,15,20-tetrakis(pentafluorophenyl) porphyrin (H2TFPP) for 60 min at $100^{\circ}C$. Results The complex was prepared with high radiochemical purity (>99% ITLC, >99% HPLC, specific activity: 13-14 GBq/mmol). Stability of the complex was checked in the final formulation and in human serum for 5 h. The partition coefficient was calculated for the compound (log P = 0.62). The biodistribution of the labeled compound in vital organs of Swiss mice bearing fibrosarcoma tumors was studied using scarification studies and SPECT imaging up to 1 h. The complex was mostly washed out from the circulation through kidneys and liver. The tumor-to-muscle ratio 1 h post injection was 5.13. Conclusion The radiolabeled porphyrin complex demonstrated potential for further imaging studies in other tumor models.

Evaluating Kyphosis and Lordosis in Students by Using a Flexible Ruler and Their Relationship with Severity and Frequency of Thoracic and Lumbar Pain

Sedigheh-Sadat Mirbagheri,Amir Rahmani-Rasa,Farzad Farmani,Payam Amini,Mohammad-Reza Nikoo 대한척추외과학회 2015 Asian Spine Journal Vol.9 No.3

Study Design: A cross-sectional, descriptive study. Purpose: This study aimed to investigate the relationship between kyphosis and lordosis measured by using a flexible ruler and musculoskeletal pain in students of Hamadan University of Medical Sciences. Overview of Literature: The spine supports the body during different activities by maintaining appropriate body alignment and posture. Normal alignment of the spine depends on its structural, muscular, bony, and articular performance. Methods: Two hundred forty-one students participated in this study. A single examiner evaluated the angles of lumbar lordosis and thoracic kyphosis by using a flexible ruler. To determine the severity and frequency of pain in low-back and inter-scapular regions, a tailor-made questionnaire with visual analog scale was used. Finally, using the Kendall correlation coefficient, the data were statistically analyzed. Results: The mean value of lumbar lordosis was 34.46°±12.61° in female students and 22.46°±9.9° in male students. The mean value of lumbar lordosis significantly differed between female and male students (p <0.001). However, there was no difference in the level of the thoracic curve (p =0.288). Relationship between kyphosis measured by using a flexible ruler and inter-scapular pain in male and female students was not significant (p =0.946). However, the relationship between lumbar lordosis and low back pain was statistically significant (p =0.006). Also, no significant relationship was observed between abnormal kyphosis and frequency of inter-scapular pain, and between lumbar lordosis and low back pain. Conclusions: Lumbar lordosis contributes to low back pain. The causes of musculoskeletal pain could be muscle imbalance and muscle and ligament strain.

Poster Session : Biotechnology ; Intranasal immunization of mice with Salmonella typhimurium PhoPc expressing heat Labile toxin B subunit of enterotoxigenic Escherichia coli

( Akbari Eidgahi Mohammad Reza ),( Amini Zahra ),( Hadji Ghorbani Amir ),( Hosseini Moghadam Neshat ),( Shaebani Ali Akbar ) 생화학분자생물학회 2007 생화학분자생물학회 춘계학술발표논문집 Vol.2007 No.-

Effect of Consumption of Whole-Wheat Breads on FBS, HbA1c, and Blood Lipids in Patients with Type 2 Diabetes

Javad Nazari,Nasrin Yadegari,Sousan Khodam,Amir Almasi-Hashian,Saeed Amini 한국식품영양과학회 2021 Preventive Nutrition and Food Science Vol.26 No.3

Whole-wheat can have positive effect on blood parameters, such as blood sugar and fat profiles, in patients with diabetic. The aim of this study was to assess the effect of whole-wheat breads on hemoglobin A1c (HbA1c) and blood lipids in patients with type 2 diabetes (T2D). The study population included men and women with T2D aged 30 years old and over in Arak, Iran. Using random sampling method, 60 patients with T2D were selected and randomly divided into control and intervention groups. After taking blood samples from the patients, the intervention group was administered 180 g of wholegrain wheat for 12 weeks. The participants were asked not to change their diets and amounts of physical activity during the study period. After 12 weeks, blood samples were taken and insulin resistance indexes, blood glucose levels, and lipid profiles were examined. The results indicated that consumption of whole-wheat bread for 12 weeks can significantly reduce body weight, and HbA1c, triglyceride, total cholesterol, and low density lipoprotein cholesterol (LDL-c) levels, and increase high density lipoprotein cholesterol (HDL-c) levels (P<0.05). However, in the control group, changes in body weight, body mass index, HbA1c, total cholesterol, HDL-c, and LDL-c levels did not significantly differ before and after the intervention period (P>0.05). As consumption of whole-wheat bread has positive effects on control of various physical and biochemical indictors in patients with diabetes, its consumption should be included in educational programs at health centers across the country.