Search results for: Mohammad Amin Samih
872 Vibration Analysis of Power Lines with Moving Dampers
Authors: Mohammad Bukhari, Oumar Barry
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In order to reduce the Aeolian vibration of overhead transmission lines, the Stockbridge damper is usually attached. The efficiency of Stockbridge damper depends on its location on the conductor and its resonant frequencies. When the Stockbridge damper is located on a vibration node, it becomes inefficient. Hence, the static damper should be subrogated by a dynamic one. In the present study, a proposed dynamic absorber for transmission lines is studied. Hamilton’s principle is used to derive the governing equations, then the system of ordinary differential equations is solved numerically. Parametric studies are conducted to determine how certain parameters affect the performance of the absorber. The results demonstrate that replacing the static absorber by a dynamic one enhance the absorber performance for wider range of frequencies. The results also indicate that the maximum displacement decreases as the absorber speed and the forcing frequency increase. However, this reduction in maximum displacement is accompanying with increasing in the steady state vibration displacement. It is also indicated that the energy dissipation in moving absorber covers higher range of frequencies.Keywords: absorber performance, Aeolian vibration, Hamilton’s principle, stockbridge damper
Procedia PDF Downloads 267871 Imidocloprid as a Systemic-Acquired Resistant (SAR) Inducer in Nicotiana tabacum Var. Samsun NN Infected with Tobacco Mild Green Mosaic Virus
Authors: Mohammad Reza Hossein Zadeh
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Plants have different layers of defense responses against biotic and abiotic stresses. One of the well-defined defense mechanism in plants is systemic acquired resistance (SAR) against a broad-range of pathogens. Salicylic acid (SA) plays a crucial role in regulation of the SAR pathway. It has been proved that Chemically SA-like compounds can mimic the SA signaling role. Imidocloprid is an insecticide being used to control whiteflies on crop plants. In order to study the possible role of Imidocloprid as an elicitor of SAR in plants, experiments were conducted in a completely randomized design frame with three treatments and duplicates on the detached leaves and whole Nicotiana tabacum var. Samsun NN. plants inoculated with Tobacco mild green mosaic virus (TMGMV). Compared with the effect of other SAR-inducers such as SA, Imidoclorid conferred a robust SAR induction in the infected plants. The results suggested that Imidocloprid even more powerful than SA can be considered as strong SAR inducer in the infected plants with viruses, which develop the local lesion symptoms.Keywords: imidocloprid, Nicotiana tabacum var. Samsun NN, SAR, tobacco mild green, mosaic virus
Procedia PDF Downloads 587870 Lowering Error Floors by Concatenation of Low-Density Parity-Check and Array Code
Authors: Cinna Soltanpur, Mohammad Ghamari, Behzad Momahed Heravi, Fatemeh Zare
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Low-density parity-check (LDPC) codes have been shown to deliver capacity approaching performance; however, problematic graphical structures (e.g. trapping sets) in the Tanner graph of some LDPC codes can cause high error floors in bit-error-ratio (BER) performance under conventional sum-product algorithm (SPA). This paper presents a serial concatenation scheme to avoid the trapping sets and to lower the error floors of LDPC code. The outer code in the proposed concatenation is the LDPC, and the inner code is a high rate array code. This approach applies an interactive hybrid process between the BCJR decoding for the array code and the SPA for the LDPC code together with bit-pinning and bit-flipping techniques. Margulis code of size (2640, 1320) has been used for the simulation and it has been shown that the proposed concatenation and decoding scheme can considerably improve the error floor performance with minimal rate loss.Keywords: concatenated coding, low–density parity–check codes, array code, error floors
Procedia PDF Downloads 356869 Evaluation of Bearing Capacity of Vertically Loaded Strip Piled-Raft Embedded in Soft Clay
Authors: Seyed Abolhasan Naeini, Mohammad Hosseinzade
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Settlement and bearing capacity of a piled raft are the two important issues for the foundations of the structures built on coastal areas from the geotechnical engineering point of view. Strip piled raft as a load carrying system could be used to reduce the possible extensive consolidation settlements and improve bearing capacity of structures in soft ground. The aim of this research was to evaluate the efficiency of strip piled raft embedded in soft clay. The efficiency of bearing capacity of strip piled raft foundation is evaluated numerically in two cases: in first case, the cap is placed directly on the ground surface and in the second, the cap is placed above the ground. Regarding to the fact that the geotechnical parameters of the soft clay are considered at low level, low bearing capacity is expected. The length, diameter and axe-to-axe distance of piles are the parameters which varied in this research to find out how they affect the bearing capacity. Results indicate that increasing the length and the diameter of the piles increase the bearing capacity. The complementary results will be presented in the final version of the paper.Keywords: soft clay, strip piled raft, bearing capacity, settlement
Procedia PDF Downloads 307868 Strengthening RC Columns Using Carbon Fiber Reinforced Epoxy Composites Modified with Carbon Nanotubes
Authors: Mohammad R. Irshidat, Mohammed H. Al-Saleh, Mahmoud Al-Shoubaki
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This paper investigates the viability of using carbon fiber reinforced epoxy composites modified with carbon nano tubes to strengthening reinforced concrete (RC) columns. Six RC columns was designed and constructed according to ASCE standards. The columns were wrapped using carbon fiber sheets impregnated with either neat epoxy or CNTs modified epoxy. These columns were then tested under concentric axial loading. Test results show that; compared to the unwrapped specimens; wrapping concrete columns with carbon fiber sheet embedded in CNTs modified epoxy resulted in an increase in its axial load resistance, maximum displacement, and toughness values by 24%, 109% and 232%, respectively. These results reveal that adding CNTs into epoxy resin enhanced the confinement effect, specifically, increased the axial load resistance, maximum displacement, and toughness values by 11%, 6%, and 19%, respectively compared with columns strengthening with carbon fiber sheet embedded in neat epoxy.Keywords: CNT, epoxy, carbon fiber, RC columns
Procedia PDF Downloads 360867 Investigation on the Kinetic Mechanism of the Reduction of Fe₂O₃/CoO-Decorated Carbon Xerogel
Authors: Mohammad Reza Ghaani, Michele Catti
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The reduction of CoO/Fe₂O₃ oxides supported on carbon xerogels was studied to elucidate the effect of nano-size distribution of the catalyst in carbon matrices. Resorcinol formaldehyde xerogels were synthesized, impregnated with iron and cobalt nitrates, and subsequently heated to obtain the oxides. The mechanism of oxide reduction to metal was investigated by in-situ synchrotron X-ray diffraction in dynamic, non-isothermal conditions. Kinetic profiles of the reactions were obtained by plotting the diffraction intensities of selected Bragg peaks vs. temperature. The extracted Temperature-Programmed-Reduction (TPR) diagrams were analyzed by appropriate kinetic models, leading to best results with the Avrami-Erofeev model for all reduction reactions considered. The activation energies for the two-step reduction of iron oxide were 65 and 37 kJmol⁻¹, respectively. The average value for the reduction of CoO to Co was found to be around 21 kJ mol⁻¹. Such results may contribute to develop efficient and inexpensive non-noble metal-based catalysts in element form, e.g., Fe, Co, via heterogenization of metal complexes on mesoporous supports.Keywords: non-isothermal kinetics, carbon aerogel, in-situ synchrotron X-ray diffraction, reduction mechanisms
Procedia PDF Downloads 240866 Sensitivity Analysis of Interference of Localised Corrosion on Bending Capacity of a Corroded RC Beam
Authors: Mohammad Mahdi Kioumarsi
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In this paper, using the response surface method (RSM), tornado diagram method and non-linear finite element analysis, the effect of four parameters on residual bending capacity of a corroded RC beam was investigated. The parameters considered are amount of localised cross section reduction, ratio of pit distance on adjacent bars to rebar distance, concrete compressive strength, and rebar tensile strength. The focus is on the influence on the bending ultimate limit state. Based on the obtained results, the effects of the ratio of pit distance to rebar distance (Lp⁄Lr) and the ratio of the localised cross section reduction to the original area of the rebar (Apit⁄A0) were found significant. The interference of localised corrosion on adjacent reinforcement bars reduces the bending capacity of under-reinforced concrete beam. Using the sensitivity analysis could lead to recognize uncertainty parameters, which have the most influences on the performance of the structure.Keywords: localised corrosion, concrete beam, sensitivity analyses, ultimate capacity
Procedia PDF Downloads 249865 Phylogenetic Analysis and a Review of the History of the Accidental Phytoplankter, Phaeodactylum tricornutum Bohlin (Bacillariophyta)
Authors: Jamal S. M. Sabir, Edward C. Theriot, Schonna R. Manning, Abdulrahman L. Al-Malki, Mohammad, Mumdooh J. Sabir, Dwight K. Romanovicz, Nahid H. Hajrah, Robert K. Jansen, Matt P. Ashworth
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The diatom Phaeodactylum tricornutum has been used as a model for cell biologists and ecologists for over a century. We have incorporated several new raphid pennates into a three-gene phylogenetic dataset (SSU, rbcL, psbC), and recover Gomphonemopsis sp. as sister to P. tricornutum with 100% BS support. This is the first time a close relative has been identified for P. tricornutum with robust statistical support. We test and reject a succession of hypotheses for other relatives. Our molecular data are statistically significantly incongruent with placement of either or both species among the Cymbellales, an order of diatoms with which both have been associated. We believe that further resolution of the phylogenetic position of P. tricornutum will rely more on increased taxon sampling than increased genetic sampling. Gomphonemopsis is a benthic diatom, and its phylogenetic relationship with P. tricornutum is congruent with the hypothesis that P. tricornutum is a benthic diatom with specific adaptations that lead to active recruitment into the plankton. We hypothesize that other benthic diatoms are likely to have similar adaptations and are not merely passively recruited into the plankton.Keywords: benthic, diatoms; ecology, Phaeodactylum tricornutum, phylogeny, tychoplankton
Procedia PDF Downloads 238864 An Innovative Green Cooling Approach Using Peltier Chip in Milling Operation for Surface Roughness Improvement
Authors: Md. Anayet U. Patwari, Mohammad Ahsan Habib, Md. Tanzib Ehsan, Md Golam Ahnaf, Md. S. I. Chowdhury
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Surface roughness is one of the key quality parameters of the finished product. During any machining operation, high temperatures are generated at the tool-chip interface impairing surface quality and dimensional accuracy of products. Cutting fluids are generally applied during machining to reduce temperature at the tool-chip interface. However, usages of cutting fluids give rise to problems such as waste disposal, pollution, high cost, and human health hazard. Researchers, now-a-days, are opting towards dry machining and other cooling techniques to minimize use of coolants during machining while keeping surface roughness of products within desirable limits. In this paper, a concept of using peltier cooling effects during aluminium milling operation has been presented and adopted with an aim to improve surface roughness of the machined surface. Experimental evidence shows that peltier cooling effect provides better surface roughness of the machined surface compared to dry machining.Keywords: aluminium, milling operation, peltier cooling effect, surface roughness
Procedia PDF Downloads 337863 Seismic Assessment of Non-Structural Component Using Floor Design Spectrum
Authors: Amin Asgarian, Ghyslaine McClure
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Experiences in the past earthquakes have clearly demonstrated the necessity of seismic design and assessment of Non-Structural Components (NSCs) particularly in post-disaster structures such as hospitals, power plants, etc. as they have to be permanently functional and operational. Meeting this objective is contingent upon having proper seismic performance of both structural and non-structural components. Proper seismic design, analysis, and assessment of NSCs can be attained through generation of Floor Design Spectrum (FDS) in a similar fashion as target spectrum for structural components. This paper presents the developed methodology to generate FDS directly from corresponding Uniform Hazard Spectrum (UHS) (i.e. design spectra for structural components). The methodology is based on the experimental and numerical analysis of a database of 27 real Reinforced Concrete (RC) buildings which are located in Montreal, Canada. The buildings were tested by Ambient Vibration Measurements (AVM) and their dynamic properties have been extracted and used as part of the approach. Database comprises 12 low-rises, 10 medium-rises, and 5 high-rises and they are mostly designated as post-disaster\emergency shelters by the city of Montreal. The buildings are subjected to 20 compatible seismic records to UHS of Montreal and Floor Response Spectra (FRS) are developed for every floors in two horizontal direction considering four different damping ratios of NSCs (i.e. 2, 5, 10, and 20 % viscous damping). Generated FRS (approximately 132’000 curves) are statistically studied and the methodology is proposed to generate the FDS directly from corresponding UHS. The approach is capable of generating the FDS for any selection of floor level and damping ratio of NSCs. It captures the effect of: dynamic interaction between primary (structural) and secondary (NSCs) systems, higher and torsional modes of primary structure. These are important improvements of this approach compared to conventional methods and code recommendations. Application of the proposed approach are represented here through two real case-study buildings: one low-rise building and one medium-rise. The proposed approach can be used as practical and robust tool for seismic assessment and design of NSCs especially in existing post-disaster structures.Keywords: earthquake engineering, operational and functional components, operational modal analysis, seismic assessment and design
Procedia PDF Downloads 213862 The Use of Artificial Intelligence to Harmonization in the Lawmaking Process
Authors: Supriyadi, Andi Intan Purnamasari, Aminuddin Kasim, Sulbadana, Mohammad Reza
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The development of the Industrial Revolution Era 4.0 brought a significant influence in the administration of countries in all parts of the world, including Indonesia, not only in the administration and economic sectors but the ways and methods of forming laws should also be adjusted. Until now, the process of making laws carried out by the Parliament with the Government still uses the classical method. The law-making process still uses manual methods, such as typing harmonization of regulations, so that it is not uncommon for errors to occur, such as writing errors, copying articles and so on, things that require a high level of accuracy and relying on inventory and harmonization carried out manually by humans. However, this method often creates several problems due to errors and inaccuracies on the part of officers who harmonize laws after discussion and approval; this has a very serious impact on the system of law formation in Indonesia. The use of artificial intelligence in the process of forming laws seems to be justified and becomes the answer in order to minimize the disharmony of various laws and regulations. This research is normative research using the Legislative Approach and the Conceptual Approach. This research focuses on the question of how to use Artificial Intelligence for Harmonization in the Lawmaking Process.Keywords: artificial intelligence, harmonization, laws, intelligence
Procedia PDF Downloads 161861 Robust Numerical Scheme for Pricing American Options under Jump Diffusion Models
Authors: Salah Alrabeei, Mohammad Yousuf
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The goal of option pricing theory is to help the investors to manage their money, enhance returns and control their financial future by theoretically valuing their options. However, most of the option pricing models have no analytical solution. Furthermore, not all the numerical methods are efficient to solve these models because they have nonsmoothing payoffs or discontinuous derivatives at the exercise price. In this paper, we solve the American option under jump diffusion models by using efficient time-dependent numerical methods. several techniques are integrated to reduced the overcome the computational complexity. Fast Fourier Transform (FFT) algorithm is used as a matrix-vector multiplication solver, which reduces the complexity from O(M2) into O(M logM). Partial fraction decomposition technique is applied to rational approximation schemes to overcome the complexity of inverting polynomial of matrices. The proposed method is easy to implement on serial or parallel versions. Numerical results are presented to prove the accuracy and efficiency of the proposed method.Keywords: integral differential equations, jump–diffusion model, American options, rational approximation
Procedia PDF Downloads 119860 Numerical Investigation of Poling Vector Angle on Adaptive Sandwich Plate Deflection
Authors: Alireza Pouladkhan, Mohammad Yavari Foroushani, Ali Mortazavi
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This paper presents a finite element model for a sandwich plate containing a piezoelectric core. A sandwich plate with a piezoelectric core is constructed using the shear mode of piezoelectric materials. The orientation of poling vector has a significant effect on deflection and stress induced in the piezo-actuated adaptive sandwich plate. In the present study, the influence of this factor for a clamped-clamped-free-free and simple-simple-free-free square sandwich plate is investigated using Finite Element Method. The study uses ABAQUS (v.6.7) software to derive the finite element model of the sandwich plate. By using this model, the study gives the influences of the poling vector angle on the response of the smart structure and determines the maximum transverse displacement and maximum stress induced.Keywords: finite element method, sandwich plate, poling vector, piezoelectric materials, smart structure, electric enthalpy
Procedia PDF Downloads 233859 Epidemiology, Prevention and Treatment of Leishmaniasis in Afghanistan
Authors: Mohammad Reza Mohammadi, Layegheh Daliri
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Introduction: Leishmaniasis occurs in infectious diseases of Leishmania protozoa in Afghanistan, anthroponotic leishmaniasis and common cutaneous leishmaniasis (ZCL). Anthroponotic skin leishmania tropica may cause urban diseases and transmitted by Phlebotomus Sergenti. In different parts of Afghanistan, different species of Leishmania are observed. We report the epidemiological characteristics of prevention and treatment in this study. Methods: This study examines the epidemiology and prevention of religious diseases in Afghanistan. Knowledge gaps were analyzed and collected with our own data. Results: In Afghanistan, most of the Lishmania Tropic seekers are Four species of Leishmania in northern Afghanistan, including Leishmania Tropica, L. Major and L. Donovani, cause skin lesions, but L. Donovani and L. infantum are visible. Even combined prevention can significantly reduce the amount of infection. Conclusion: Skinny, as well as visceral leishmaniasis, can occur among the returnees from Afghanistan. Unusual and poor skin lesions can be created by L. Donovani. In most pathogenic areas, the transmission of common diseases between humans and animals. Home dogs are the main reservoir, transferring in some areas such as India and Sudan.Keywords: leishmania donovani, leishmania tropica, treatment, disease, epidemiology
Procedia PDF Downloads 180858 Evaluation of Humoral Immune Response Against Somatic and Excretory- Secretory Antigens of Dicrocoelium Dendriticum in Infected Sheep by Western Blot
Authors: Arash Jafari, Somaye Bahrami, Mohammad Hossein Razi Jalali
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The aim of this study was the isolation and identification of excretory-secretory and somatic antigens from D. dendriticum by SDS-PAGE and evaluation of humeral immune response against these antigens. The sera of infected sheep with different infection degrees were collected. Somatic and ES proteins were isolated with SDS PAGE. Immunogenicity properties of the resulting proteins were determined using western blot analysis. The total extract of somatic antigens analysed by SDS-PAGE revealed 21 proteins. In mild infection, bands of 130 KDa were immune dominant. In moderate infections 48, 80 and 130 KDa and in heavy infections 48, 60, 80, 130 KDa were detected as immune dominant bands. In ES antigens, mild infection 130 KDa, in moderate infection 100, 120 and 130 KDa and in heavy infection 45, 80, 85, 100, 120 and 130 KDa were immune dominant bands. The most immunogenic protein band during different degrees of infection was 130KDa.Keywords: Dicrocoelium dendriticum excretory-secretory antigens, somatic antigens, western blot
Procedia PDF Downloads 602857 Evaluation of in vitro Inhibitory Effect of Enoxacin on Babesia and Theileria Parasites
Authors: Mosaab A. Omar, Mohammad Saleh Al-Aboody, Mohmed A. Rizk, Shimaa M. Elsayed, Ahmed ElSify, Naoaki Yokoyama, Ikuo Igarashi
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Enoxacin is a broad-spectrum 6-fluoronaphthyridinone antibacterial agent (fluoroquinolones) structurally related to nalidixic acid used mainly in the treatment of urinary tract infections and gonorrhea. Also, it has been shown recently that it may have cancer inhibiting effect. The primary antibabesial effect of Enoxacin is due to inhibition of DNA gyrase subunit A, and DNA topoisomerase. In the present study, enoxacin was tested as a potent inhibitor against the in vitro growth of bovine and equine Piroplasms. The in vitro growth of five Babesia species that were tested was significantly inhibited (P<0.05) by micromolar concentrations of enoxacin (IC50 values= 13.5, 7.2, 7.5, and 24.2 µM for Babesia bovis, Babesia bigemina, Babesia caballi, and Theileria equi, respectively). Enoxacin IC50 values for Babesia and Theileria parasites were satisfactory as the drug is a potent antibacterial drug with minimum side effects. Therefore, enoxacin might be used for the treatment of Babesiosis and Theileriosis especially in case of mixed infections with bacterial diseases or in the case of animal sensitivity against diminazin toxicity.Keywords: enoxacin, Babesia, Theileria, IC50 and dimenazin
Procedia PDF Downloads 468856 Psychoanalytical Foreshadowing: The Application of a Literary Device in Quranic Narratology
Authors: Fateme Montazeri
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Literary approaches towards the text of the Quran predate the modern period. Suyuti (d.1505)’s encyclopedia of Quranic sciences, Al-Itqan, provides a notable example. In the modern era, the study of the Quranic rhetorics received particular attention in the second half of the twentieth century by Egyptian scholars. Amin Al-Khouli (d. 1966), who might be considered the first to argue for the necessity of applying a literary-rhetorical lens toward the tafseer, Islamic exegesis, and his students championed the literary analysis as the most effective approach to the comprehension of the holy text. Western scholars continued the literary criticism of the Islamic scripture by applying to the Quran similar methodologies used in biblical studies. In the history of the literary examination of the Quran, the scope of the critical methods applied to the Quranic text has been limited. For, the rhetorical approaches to the Quran, in the premodern as well as the modern period, concerned almost exclusively with the lexical layer of the text, leaving the narratological dimensions insufficiently examined. Recent contributions, by Leyla Ozgur Alhassen, for instance, attempt to fill this lacunae. This paper aims at advancing the studies of the Quranic narratives by investigating the application of a literary device whose role in the Quranic stories remains unstudied, that is, “foreshadowing.” This paper shall focus on Chapter 12, “Surah al-Yusuf,” as its case study. Chapter 12, the single chapter that includes the story of Joseph in one piece, contains several instances in which the events of the story are foreshadowed. As shall be discussed, foreshadowing occurs either through a monolog or dialogue whereby one or more of the characters allude to the future happenings or through the manner in which the setting is described. Through a close reading of the text, it will be demonstrated that the usage of the rhetorical tool of foreshadowing meets a dual purpose: on the one hand, foreshadowing prepares the reader/audience for the upcoming events in the plot, and on the other hand, it highlights the psychological dimensions of the characters, their thoughts, intentions, and disposition. In analyzing the story, this study shall draw on psychoanalytical criticism to explore the layers of meanings embedded in the Quranic narrative that are unfolded through foreshadowing.Keywords: foreshadowing, quranic narrative, literary criticism, surah yusuf
Procedia PDF Downloads 153855 The Effects of Combination of Melatonin with and without Zinc on Gonadotropin Hormones in Female Rats
Authors: Fariba Rahimi, Morteza Zendedel, Mohammad Jaafar Rezaee, Bita Vazir, Shahin Fakour
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The present study was carried out to investigate the effect of melatonin (Mel) with and without zinc (Zn) on the gonadotropin hormones, also thyroid (T3 and T4) hormone concentration in female rats. A total of 40 adult female rats were randomly grouped into five treatment groups, each of 2 rats in a Completely Randomized Design (CRD) entire research time. Daily was treated by gavage with Zn and melatonin as follows: T1 (control1, basal diet), T2 (control 2, treated with normal saline) and other experimental groups, including T3, T4 and T5, were treated with a dose of zinc (40 ppm), melatonin (5 mg/kg), and combination zinc plus melatonin with the same level, respectively. Blood FSH and LH concentrations were measured. The result showed no significant differences between treatments in FSH and LH levels. The estrogen and progesterone and TSH levels in rats that received 5 mg of melatonin per day were higher than in other groups but not statistically significant (P>0.05). However, T3 (thyroid) concentration significantly (P<0.05) decreased in the group that received 40 mg/zinc per Kg compared to other groups. No significant (P>0.05) difference was detected among treatments in T4 levels. In conclusion, except for T3, had no significant (P>0.05) effect on another parameter in the female rats that received melatonin or zinc and a blend of melatonin and Zn.Keywords: zinc, melatonin, hormone, rat
Procedia PDF Downloads 109854 ANN Based Simulation of PWM Scheme for Seven Phase Voltage Source Inverter Using MATLAB/Simulink
Authors: Mohammad Arif Khan
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This paper analyzes and presents the development of Artificial Neural Network based controller of space vector modulation (ANN-SVPWM) for a seven-phase voltage source inverter. At first, the conventional method of producing sinusoidal output voltage by utilizing six active and one zero space vectors are used to synthesize the input reference, is elaborated and then new PWM scheme called Artificial Neural Network Based PWM is presented. The ANN based controller has the advantage of the very fast implementation and analyzing the algorithms and avoids the direct computation of trigonometric and non-linear functions. The ANN controller uses the individual training strategy with the fixed weight and supervised models. A computer simulation program has been developed using Matlab/Simulink together with the neural network toolbox for training the ANN-controller. A comparison of the proposed scheme with the conventional scheme is presented based on various performance indices. Extensive Simulation results are provided to validate the findings.Keywords: space vector PWM, total harmonic distortion, seven-phase, voltage source inverter, multi-phase, artificial neural network
Procedia PDF Downloads 452853 Combined Model Predictive Controller Technique for Enhancing NAO Gait Stabilization
Authors: Brahim Brahmi, Mohammed Hamza Laraki, Mohammad Habibur Rahman, Islam M. Rasedul, M. Assad Uz-Zaman
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The humanoid robot, specifically the NAO robot must be able to provide a highly dynamic performance on the soccer field. Maintaining the balance of the humanoid robot during the required motion is considered as one of a challenging problems especially when the robot is subject to external disturbances, as contact with other robots. In this paper, a dynamic controller is proposed in order to ensure a robust walking (stabilization) and to improve the dynamic balance of the robot during its contact with the environment (external disturbances). The generation of the trajectory of the center of mass (CoM) is done by a model predictive controller (MPC) conjoined with zero moment point (ZMP) technique. Taking into account the properties of the rotational dynamics of the whole-body system, a modified previous control mixed with feedback control is employed to manage the angular momentum and the CoM’s acceleration, respectively. This latter is dedicated to provide a robust gait of the robot in the presence of the external disturbances. Simulation results are presented to show the feasibility of the proposed strategy.Keywords: preview control, Nao robot, model predictive control
Procedia PDF Downloads 128852 Optimal Design of Composite Patch for a Cracked Pipe by Utilizing Genetic Algorithm and Finite Element Method
Authors: Mahdi Fakoor, Seyed Mohammad Navid Ghoreishi
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Composite patching is a common way for reinforcing the cracked pipes and cylinders. The effects of composite patch reinforcement on fracture parameters of a cracked pipe depend on a variety of parameters such as number of layers, angle, thickness, and material of each layer. Therefore, stacking sequence optimization of composite patch becomes crucial for the applications of cracked pipes. In this study, in order to obtain the optimal stacking sequence for a composite patch that has minimum weight and maximum resistance in propagation of cracks, a coupled Multi-Objective Genetic Algorithm (MOGA) and Finite Element Method (FEM) process is proposed. This optimization process has done for longitudinal and transverse semi-elliptical cracks and optimal stacking sequences and Pareto’s front for each kind of cracks are presented. The proposed algorithm is validated against collected results from the existing literature.Keywords: multi objective optimization, pareto front, composite patch, cracked pipe
Procedia PDF Downloads 312851 The Effect of Different Parameters on a Single Invariant Lateral Displacement Distribution to Consider the Higher Modes Effect in a Displacement-Based Pushover Procedure
Authors: Mohamad Amin Amini, Mehdi Poursha
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Nonlinear response history analysis (NL-RHA) is a robust analytical tool for estimating the seismic demands of structures responding in the inelastic range. However, because of its conceptual and numerical complications, the nonlinear static procedure (NSP) is being increasingly used as a suitable tool for seismic performance evaluation of structures. The conventional pushover analysis methods presented in various codes (FEMA 356; Eurocode-8; ATC-40), are limited to the first-mode-dominated structures, and cannot take higher modes effect into consideration. Therefore, since more than a decade ago, researchers developed enhanced pushover analysis procedures to take higher modes effect into account. The main objective of this study is to propose an enhanced invariant lateral displacement distribution to take higher modes effect into consideration in performing a displacement-based pushover analysis, whereby a set of laterally applied displacements, rather than forces, is monotonically applied to the structure. For this purpose, the effect of different parameters such as the spectral displacement of ground motion, the modal participation factor, and the effective modal participating mass ratio on the lateral displacement distribution is investigated to find the best distribution. The major simplification of this procedure is that the effect of higher modes is concentrated into a single invariant lateral load distribution. Therefore, only one pushover analysis is sufficient without any need to utilize a modal combination rule for combining the responses. The invariant lateral displacement distribution for pushover analysis is then calculated by combining the modal story displacements using the modal combination rules. The seismic demands resulting from the different procedures are compared to those from the more accurate nonlinear response history analysis (NL-RHA) as a benchmark solution. Two structures of different heights including 10 and 20-story special steel moment resisting frames (MRFs) were selected and evaluated. Twenty ground motion records were used to conduct the NL-RHA. The results show that more accurate responses can be obtained in comparison with the conventional lateral loads when the enhanced modal lateral displacement distributions are used.Keywords: displacement-based pushover, enhanced lateral load distribution, higher modes effect, nonlinear response history analysis (NL-RHA)
Procedia PDF Downloads 278850 The Effects of Combination of Melatonin with and Without Zinc on Gonadotropin Hormones in Female Rats
Authors: Fariba Rahimi, Morteza Zendedel, Mohammad Jaafar Rezaee, Bita Vazir, Shahin Fakour
Abstract:
The present study was carried out to investigate the effect of melatonin (Mel) with and without zinc (Zn) on the gonadotropin hormones, also thyroid (T3 and T4) hormone concentration in female rat. A total of 40 adult female rats were randomly grouped into five treatment groups, each of 2 rats in a Completely Randomized Design (CRD) entire research time. Daily were treated by gavaging with Zn and melatonin as following: T1 (control1, basal diet), T2 (control 2, treated with normal saline) and other experimental groups including T3, T4 and T5 were treated with dose of zinc (40 ppm), melatonin (5 mg/kg), and combination zinc plus melatonin with the same level, respectively. Blood FSH and LH concentration were measured. Result showed no significantly differences between treatments in FSH and LH levels. The estrogen and progesterone and TSH levels in rats that received 5 mg of melatonin per day were higher than other groups, but not statistically significant (P>0.05). However, T3 (thyroid) concentration significantly (P<0.05) decreased in group that received 40 mg/zinc per Kg compared other groups. No significant (P>0.05) difference was detected among treatments in T4 levels. In conclusion, except for T3, had not significantly (P>0.05) effect on another parameters in the female rats that received melatonin or zinc and blend of melatonin and Zn.Keywords: zinc, melatonin, hormone, rat
Procedia PDF Downloads 122849 Workaholism: A Study of Iranian Journalists at Gender, Career, and Educational Diversity
Authors: Minavand Mohammad, Maghsoudi Masoud, Mousavi Mahdis, Vahed Zahra, Hamidi Shabnam
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While workaholism in organizations has received considerable popular attention, our understanding of it on the basis of research proof is limited. This comes from the deficiency of both appropriate definitions and measures of the concept. The purpose of this paper is to investigate gender, career and educational diversity in three workaholism components among Iranian journalists. Data were collected from 243 journalists (110 men and 133 women) using nameless completed questionnaires, with a 48 percent response rate. No gender differences found between male and female respondents, so there seems no consistency with previous findings. Furthermore, the results showed that different levels of jobs and education score correspondingly on the measures of work involvement, feeling driven to work and work enjoyment. All data are gathered using self report questionnaires. It is not evident the extent to which these findings would generalize to men and women in other vocations. This investigation has a contribution to the small but growing literature on flow and optimal experience in media organizations in Iran.Keywords: gender, career, education, workaholism, Iranian journalists, work involvement, work enjoyment, feeling driven to work
Procedia PDF Downloads 387848 Effects of Temperature Dryer on Allicin and Pirvic Acid Measurments Garlic Powder after Drying Process
Authors: Rezvani Aghdam Ali, Aleemrani Nejad Seyed Mohammad Hossein
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Introduction: Dryed Garlic has plentiful health and medicinal value and is used in industrial food the forms of flakes or powders. Many health and medicinal properties of Garlic are attributed to allicin. This substance is produced enzymatically after crushing. Since temperature affected on enzymatic action, then is important factor on pirovic acid and allicin retention. Materials and Methods: This study investigated the effects of temperature on qualitative characteristics such as color of powder and pirovic acid and alicin retention in a convective hot-air dryer. For this reason, half cloves of Shushtar Garlics (Allium sativum L.) were dried at air temperatures of 50 and 70°C. Results: Results showed that increasing temperature was resulted changing color. Pirovic acid increased when half cloves Garlic were dried at 70°C. Allicin of half cloves also increased with increasing temperature. Conclusions: According to findings of this research, half cloves which dried in 70 degree centigrade can be introduced the best conditions for producing Garlic powder.Keywords: garlic, drying, pirovic acid, allicin
Procedia PDF Downloads 332847 Assessment of Body Mass Index among Children of Primary School in Behbahan City
Authors: Hosseini Siahi Zohreh, Sana Mohammad Jafar
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With increase in fat and over weight in children and its undesirable effects on different organisms of the body and since many of the sicknesses are due to over weight and with losing weight these sicknesses disappear, and on the other hand with mal nutrition and under weight in children other kind of sicknesses such as derogation of body's security system, frequent infection, insufficient growth, shortness, and delay in maturity etc. are some of the signs of being under weight. Therefore recognition of signs of over weight and under weight and their prevalence in children are important. To determine this difficulty we have used the body mass index as screening tool since it is very prevalent and a good and important guide and has very good relation with body fat in children. In this study 2321 students from primary schools in Behbahan have been chosen randomly and evaluated by height and weight and their body mass index have been calculated and then recorded on the BMI percentile diagram which is for age and gender. The following results obtained: The amount of total fat, over weight and slimness are 9.3, 12.1 and 12.32 percent respectively. Therefore 21.4% of the children were over weighted. It did not show any meaningful statistical relation in fat conditions among boys and girls, but there has been a meaningful statistical relation in slimness among boys and girls.Keywords: assessment, students, Behbahan, Body Mass Index
Procedia PDF Downloads 519846 Burnout and Salivary Cortisol Among Laboratory Personnel in Klang Valley, Malaysia During COVID-19 Pandemic
Authors: Maznieda Mahjom, Rohaida Ismail, Masita Arip, Mohd Shaiful Azlan, Nor’Ashikin Othman, Hafizah Abdullah, nor Zahrin Hasran, Joshita Jothimanickam, Syaqilah Shawaluddin, Nadia Mohamad, Raheel Nazakat, Tuan Mohd Amin, Mizanurfakhri Ghazali, Rosmanajihah Mat Lazim
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COVID-19 outbreak is particularly detrimental to the mental health of everyone as well as leaving a long devastating crisis in the healthcare sector. Daily increment of COVID-19 cases and close contact, necessitating the testing of a large number of samples, thus increasing the workload and burden to laboratory personnel. This study aims to determine the prevalence of personal-, work- and client-related burnout as well as to measure the concentration of salivary cortisol among laboratory personnel in the main laboratories in Klang Valley, Malaysia. This cross-sectional study was conducted in late 2021 and recruited a total of 404 respondents from three laboratories in Klang Valley, Malaysia. The level of burnout was assessed using Copenhagen Burnout Inventory (CBI) comprising three sub-dimensions of personal-, work- and client-related burnout. The cut-off score of 50% and above indicated possible burnout. Meanwhile, salivary cortisol was measured using a competitive enzyme immunoassay kit (Salimetrics, State College, PA, USA). Normal levels of salivary cortisol concentration in adults are within 0.094 to 1.551 μg/dl (morning) and can be none detected to 0.359 μg/dl (evening). The prevalence of personal-, work- and client-related burnout among laboratory personnel were 36.1%, 17.8% and 7.2% respectively. Meanwhile, the abnormal morning and evening cortisol concentration recorded were 29.5% and 21.8% excluding 6.9%-7.4% missing data. While the IgA level is normal for most of the respondents, which recorded at 95.53%. Laboratory personnel were at risk of suffering burnout during the COVID-19 pandemic. Thus, mental health programs need to be addressed at the department and hospital level by regularly screening healthcare workers and designing an intervention program. It is also vital to improve the coping skills of laboratory personnel by increasing the awareness of good coping skill techniques. The training must be in an innovative way to ensure that the lab personnel can internalise the technique and practise it in real life.Keywords: burnout, COVID-19, laborotary personnel, salivary cortisol
Procedia PDF Downloads 68845 A Bi-Objective Stochastic Mathematical Model for Agricultural Supply Chain Network
Authors: Mohammad Mahdi Paydar, Armin Cheraghalipour, Mostafa Hajiaghaei-Keshteli
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Nowadays, in advanced countries, agriculture as one of the most significant sectors of the economy, plays an important role in its political and economic independence. Due to farmers' lack of information about products' demand and lack of proper planning for harvest time, annually the considerable amount of products is corrupted. Besides, in this paper, we attempt to improve these unfavorable conditions via designing an effective supply chain network that tries to minimize total costs of agricultural products along with minimizing shortage in demand points. To validate the proposed model, a stochastic optimization approach by using a branch and bound solver of the LINGO software is utilized. Furthermore, to accumulate the data of parameters, a case study in Mazandaran province placed in the north of Iran has been applied. Finally, using ɛ-constraint approach, a Pareto front is obtained and one of its Pareto solutions as best solution is selected. Then, related results of this solution are explained. Finally, conclusions and suggestions for the future research are presented.Keywords: perishable products, stochastic optimization, agricultural supply chain, ɛ-constraint
Procedia PDF Downloads 365844 The Value of Audit in Managing Supplier’s Process Improvement
Authors: Mohammad E. Nikoofal, Mehmet Gumus
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Besides the many benefits of outsourcing, firms are still concerned about the lack of critical information regarding both the risk levels and actions of their suppliers that are just a few links away. In this paper, we study the effectiveness of audit for the manufacturer in managing her supplier’s process improvement effort when the supplier is privately informed about his disruption risk and actions. By comparing the agency costs associated with the optimal menu of contracts with and without audit, we completely characterize the value of audit for all the cases from the perspectives of both manufacturer, and supplier as well as total supply chain. First, the analysis of value of audit from the manufacturer’s perspective shows that she can strictly benefit from auditing her supplier’s actions. To the best of our knowledge, this result has not been documented before in the principal-agent literature under a standard setting where the agent is assumed to be risk-neutral and not protected by limited liability constraints. Second, we find that not only the manufacturer but also the supplier can strictly benefit from audit. Third, the audit enables the manufacturer to customize her contract offerings based on the reliability of the supplier. Finally, by analyzing the impact of problem parameters on the value of audit, we identify the conditions under which an audit would be beneficial for individual supply chain parties as well as total supply chain.Keywords: supply disruption, adverse selection, moral hazard incentives, audit
Procedia PDF Downloads 461843 The Effect of Tax Avoidance on Firm Value: Evidence from Amman Stock Exchange
Authors: Mohammad Abu Nassar, Mahmoud Al Khalilah, Hussein Abu Nassar
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The purpose of this study is to examine whether corporate tax avoidance practices can impact firm value in the Jordanian context. The study employs a quantitative approach using s sample of (124) industrial and services companies listed on the Amman Stock Exchange for the period from 2010 to 2019. Multiple linear regression analysis has been applied to test the study's hypothesis. The study employs effective tax rate and book-tax difference to measure tax avoidance and Tobin's Q factor to measure firm value. The results of the study revealed that tax avoidance practices, when measured using effective tax rates, do not significantly impact firm value. When the book-tax difference is used to measure tax avoidance, the study results showed a negative impact on firm value. The result of the study has not supported the traditional view of tax avoidance as a transfer of wealth from the government to shareholders for industrial and services companies listed on the Amman Stock Exchange, indicating that Jordanian firms should not use tax avoidance strategies to enhance their value.Keywords: tax avoidance, effective tax rate, book-tax difference, firm value, Amman stock exchange
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