Search results for: Mahmoud Reza Hosseini
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 947

Search results for: Mahmoud Reza Hosseini

947 Formulating the Stochastic Finite Elements for Free Vibration Analysis of Plates with Variable Elastic Modulus

Authors: Mojtaba Aghamiri Esfahani, Mohammad Karkon, Seyed Majid Hosseini Nezhad, Reza Hosseini-Ara

Abstract:

In this study, the effect of uncertainty in elastic modulus of a plate on free vibration response is investigated. For this purpose, the elastic modulus of the plate is modeled as stochastic variable with normal distribution. Moreover, the distance autocorrelation function is used for stochastic field. Then, by applying the finite element method and Monte Carlo simulation, stochastic finite element relations are extracted. Finally, with a numerical test, the effect of uncertainty in the elastic modulus on free vibration response of a plate is studied. The results show that the effect of uncertainty in elastic modulus of the plate cannot play an important role on the free vibration response.

Keywords: stochastic finite elements, plate bending, free vibration, Monte Carlo, Neumann expansion method.

Procedia PDF Downloads 357
946 A Comparative Study of Language Learning Strategy Use of Iranian Kurdish Bilingual and Persian Monolingual in EFL Context

Authors: Reza Khani, Ziba Hosseini

Abstract:

This study was an attempt to investigate the difference between learners of Iranian Kurdish–Persian bilingual language and Persian monolinguals, regarding language strategy use (LLS). The participants of the study were 120 monolingual Persian and 120 bilingual Kurdish studying English as a foreign language (EFL). Data were collected using strategy inventory for language learning SILL. The results show bilingual reported higher use of language learning strategies in all categories of SILL except memory strategies.

Keywords: language learning, memory, monolingual, comparative study

Procedia PDF Downloads 372
945 Effectiveness of Language Learning Strategy Instruction Based on CALLA on Iranian EFL Language Strategy Use

Authors: Reza Khani, Ziba Hosseini

Abstract:

Ever since the importance of language learning strategy instruction (LLS) has been distinguished, there has been growing interest on how to teach LLS in language learning classrooms. So thus this study attempted to implement language strategy instruction based on CALLA approach for Iranian EFL learners in a real classroom setting. The study was testing the hypothesis that strategy instruction result in improved linguistic strategy of students. The participant of the study were 240 EFL learners who received language learning instruction for four months. The data collected using Oxford strategy inventory for language learning. The results indicated the instruction had statistically significant effect on language strategy use of intervention group who received instruction.

Keywords: CALLA, language learning strategy, language learning strategy instruction, Iranian EFL language strategy

Procedia PDF Downloads 531
944 Numerical Investigation of Natural Convection of Pine, Olive and Orange Leaves

Authors: Ali Reza Tahavvor, Saeed Hosseini, Nazli Jowkar, Behnam Amiri

Abstract:

Heat transfer of leaves is a crucial factor in optimal operation of metabolic functions in plants. In order to quantify this phenomenon in different leaves and investigate the influence of leaf shape on heat transfer, natural convection for pine, orange and olive leaves was simulated as representatives of different groups of leaf shapes. CFD techniques were used in this simulation with the purpose to calculate heat transfer of leaves in similar environmental conditions. The problem was simulated for steady state and three-dimensional conditions. From obtained results, it was concluded that heat fluxes of all three different leaves are almost identical, however, total rate of heat transfer have highest and lowest values for orange leaves and pine leaves, respectively.

Keywords: computational fluid dynamic, heat flux, heat transfer, natural convection

Procedia PDF Downloads 324
943 Finding the Free Stream Velocity Using Flow Generated Sound

Authors: Saeed Hosseini, Ali Reza Tahavvor

Abstract:

Sound processing is one the subjects that newly attracts a lot of researchers. It is efficient and usually less expensive than other methods. In this paper the flow generated sound is used to estimate the flow speed of free flows. Many sound samples are gathered. After analyzing the data, a parameter named wave power is chosen. For all samples, the wave power is calculated and averaged for each flow speed. A curve is fitted to the averaged data and a correlation between the wave power and flow speed is founded. Test data are used to validate the method and errors for all test data were under 10 percent. The speed of the flow can be estimated by calculating the wave power of the flow generated sound and using the proposed correlation.

Keywords: the flow generated sound, free stream, sound processing, speed, wave power

Procedia PDF Downloads 360
942 Spectra of Mahmoud Darwish: Argumentative Approach in the Poem "Identity Card"

Authors: Haitham Sarhan

Abstract:

The experience of Mahmoud Darwish’s poetry represents one of the leading Arabic creative experiences because of its cultural specificity which is linked to the question of Palestine and its people. The poet Mahmoud Darwish does not stop there, but also reaches out to the whole of the cosmic and openness of the universal human experience. His poetry is rooted in a creative period, and was able to surpass its time. Mahmoud Darwish’s poetry contains diverse metaphors and worlds of genres, which overextends from direct romance to the lattice resistance and further stretches to the imaginary world and to the grand narratives. The poem "Identity Card" was published in his collections "Olive Leaves" and was issued in 1963. This collection highlighted the poems which included a revolutionary position, and formed a 'manifesto' and the statement of the Palestinian resistance, which represented the league of poets of Palestine. This poem has contributed along with other poems in creating a flame of resistance and increased it in the hearts of the Palestinian people. It also exercised considerable influence in the Arab world through what has been wrought from emotional responses and revolutionary impact which still remains. Moreover, this poem has succeeded with other resistance poems and postmodern poets like Nizar Qabbani in bringing modern poetry and culturally transmitted it among the Arab peoples and the masses. In spite of the fact that the poet Mahmoud Darwish exceeded this poem creatively through his other great works, "Identity Card" still has a great effect on peoples past memory’s and present. This need to hear this poem in Mahmoud Darwish’s poetic readings reflects peoples frustration and anger. It is safe to say that it is enticing people to this present day. This revolutionary poem had and still has a magical effect on Arab world.

Keywords: Arab contemporary poetry, identity, memory, argumentation

Procedia PDF Downloads 394
941 Writing Style in a Thousand Splendid Suns

Authors: Maroof Sakhi

Abstract:

This article studies writing style in A Thousand Splendid Suns. It mainly discusses code-switching and usage of Persian words in the novel. Hosseini mainly writes in English; however, constantly he applies Persian words, phrases and syntax. Code-switching is used for different purposes in A Thousand Splendid Suns. It gives a voice to a character from Afghanistan. It is also used to mark a difference between the American and Afghanistan cultures and languages. Furthermore, representation of Persian language can be interpreted as valorization of the author’s mother tongue. In short, the writing style in A Thousand Splendid Suns represents Hosseini’s identity, culture and linguistic background.

Keywords: code-switching, hybridity, identity, linguistic background, Persian literature

Procedia PDF Downloads 68
940 Investigating the Energy Gap and Wavelength of (AlₓGa₁₋ₓAs)ₘ/(GaAs)ₙ Superlattices in Terms of Material Thickness and Al Mole Fraction Using Empirical Tight-Binding Method

Authors: Matineh Sadat Hosseini Gheidari, Vahid Reza Yazdanpanah

Abstract:

In this paper, we used the empirical tight-binding method (ETBM) with sp3s* approximation and considering the first nearest neighbor with spin-orbit interactions in order to model superlattice structure (SLS) of (AlₓGa₁₋ₓAs)ₘ/(GaAs)ₙ grown on GaAs (100) substrate at 300K. In the next step, we investigated the behavior of the energy gap and wavelength of this superlattice in terms of different thicknesses of core materials and Al mole fractions. As a result of this survey, we found out that as the Al composition increases, the energy gap of this superlattice has an upward trend and ranges from 1.42-1.63 eV. Also, according to the wavelength range that we gained from this superlattice in different Al mole fractions and various thicknesses, we can find a suitable semiconductor for a special light-emitting diode (LED) application.

Keywords: energy gap, empirical tight-binding method, light-emitting diode, superlattice, wavelength

Procedia PDF Downloads 158
939 Numerical Investigation of the Effect of Number of Waves on Heat Transfer in a Wavy Wall Enclosure

Authors: Ali Reza Tahavvor, Saeed Hosseini, Afshin Karimzadeh Fard

Abstract:

In this paper the effect of wall waviness of side walls in a two-dimensional wavy enclosure is numerically investigated. Two vertical wavy walls and straight top wall are kept isothermal and the bottom wall temperature is higher and spatially varying with cosinusoidal temperature distribution. A computational code based on Finite-volume approach is used to solve governing equations and SIMPLE method is used for pressure velocity coupling. Test is performed for several different numbers of undulations. The Prandtl number was kept constant and the Ra number denotes that the flow is laminar. Temperature and velocity fields are determined. Therefore, according to the obtained results a correlation is proposed for average Nusselt number as a function of number of side wall waves. The results indicate that the Nusselt number is highly affected by number of waves and increasing it decreases the wavy walls Nusselt number; although the Nusselt number is not highly affected by surface waviness when the number of undulations is below one.

Keywords: cavity, natural convection, Nusselt number, wavy wall

Procedia PDF Downloads 425
938 Effects of Specific Essential Oil Compounds on, Feed Intake, Milk Production, and Ruminal Environment in Dairy Cows during Heat Exposure

Authors: Kamran Reza-Yazdi, Mohammad Fallah, Mahdi Khodaparast, Farshad Kateb, Morteza Hosseini-Ghaffari

Abstract:

The objective of this study was to determine effect of dietary essential oil (EO) compounds, which contained cinnamaldehyde, eugenol, peppermint, coriander, cumin, lemongrass, and an organic carrier on feed intake, milk composition, and rumen fermentation of dairy cows during heat exposure. Thirty-two Holstein cows (days in milk= 60 ± 5) were assigned to one of two treatment groups: a Control and EO fed. The experiment lasted 28 days. Dry matter intake (DMI) was measured daily while and milk production was measured weekly. Our result showed that DMI and milk yield was decreased (P < 0.01) in control cows relative to EO cows. Furthermore, supplementation with EO was associated with a decrease in the molar proportion of propionate (P < 0.05) and increase (P < 0.05) in acetate to propionate ratio. In conclusion, EO supplementations in diets can be useful nutritional modification to alleviate for the decrease DMI and milk production during heat exposure in lactating dairy cows.

Keywords: dairy cow, feed additive, plant extract, eugenol

Procedia PDF Downloads 761
937 A Concept in Addressing the Singularity of the Emerging Universe

Authors: Mahmoud Reza Hosseini

Abstract:

The universe is in a continuous expansion process, resulting in the reduction of its density and temperature. Also, by extrapolating back from its current state, the universe at its early times has been studied known as the big bang theory. According to this theory, moments after creation, the universe was an extremely hot and dense environment. However, its rapid expansion due to nuclear fusion led to a reduction in its temperature and density. This is evidenced through the cosmic microwave background and the universe structure at a large scale. However, extrapolating back further from this early state reaches singularity which cannot be explained by modern physics and the big bang theory is no longer valid. In addition, one can expect a nonuniform energy distribution across the universe from a sudden expansion. However, highly accurate measurements reveal an equal temperature mapping across the universe which is contradictory to the big bang principles. To resolve this issue, it is believed that cosmic inflation occurred at the very early stages of the birth of the universe According to the cosmic inflation theory, the elements which formed the universe underwent a phase of exponential growth due to the existence of a large cosmological constant. The inflation phase allows the uniform distribution of energy so that an equal maximum temperature could be achieved across the early universe. Also, the evidence of quantum fluctuations of this stage provides a means for studying the types of imperfections the universe would begin with. Although well-established theories such as cosmic inflation and the big bang together provide a comprehensive picture of the early universe and how it evolved into its current state, they are unable to address the singularity paradox at the time of universe creation. Therefore, a practical model capable of describing how the universe was initiated is needed. This research series aims at addressing the singularity issue by introducing an energy conversion mechanism. This is accomplished by establishing a state of energy called a “neutral state”, with an energy level which is referred to as “base energy” capable of converting into other states. Although it follows the same principles, the unique quanta state of the base energy allows it to be distinguishable from other states and have a uniform distribution at the ground level. Although the concept of base energy can be utilized to address the singularity issue, to establish a complete picture, the origin of the base energy should be also identified. This matter is the subject of the first study in the series “A Conceptual Study for Investigating the Creation of Energy and Understanding the Properties of Nothing” which is discussed in detail. Therefore, the proposed concept in this research series provides a road map for enhancing our understating of the universe's creation from nothing and its evolution and discusses the possibility of base energy as one of the main building blocks of this universe.

Keywords: big bang, cosmic inflation, birth of universe, energy creation

Procedia PDF Downloads 47
936 Detection of Leishmania Mixed Infection from Phlebotomus papatasi in Central Iran

Authors: Nassibeh Hosseini-Vasoukolaei, Amir Ahmad Akhavan, Mahmood Jeddi-Tehrani, Ali Khamesipour, Mohammad Reza Yaghoobi Ershadi, Kamhawi Shaden, Valenzuela Jesus, Hossein Mirhendi, Mohammad Hossein Arandian

Abstract:

Zoonotic cutaneous leishmaniasis (ZCL) is an endemic disease in many rural areas of Iran. Sand flies were collected from rural areas of Esfahan province and were identified using valid identification keys. DNA was extracted from sand flies and Nested PCRs were done using specific primers. In this study, 44 out of 152 (28.9 %) sand flies were infected with L. majoralone. Eight sand flies showed mixed infection: four sand flies (2.6 %) were infected with L. major, L. turanicaand L. gerbili, one sand fly (0.7 %) was infected with L. major and L. turanica and three sand flies (2 %) were infected with L. turanicaand L. gerbili. Our results demonstrate the natural infection of P. papatasi sand fly with three species of L. major, L. turanica and L. gerbili which are circulating among R. opimusreservoir host and P. papatasi sand fly vector in central Iran.

Keywords: Phlebotomus papatasi, Leishmania major, Leishmania turanica, Leishmania gerbili, mixed infection, Iran

Procedia PDF Downloads 436
935 The Role of Brand Experience in Customer Satisfaction and Customer Loyalty in Ayandeh Bank Branches in Tehran

Authors: Seyed Reza Agha Seyed Hosseini, Nicolas Hamelin

Abstract:

Many marketing executives are looking for a comprehensive plan for delivering quality services and products that will create a distinct and unforgettable long-term experience for customers in dealing with their brand. Various brand management experts believe that a company looking to enhance its brand experience in the minds of customers should have a plan to increase customer satisfaction as well as customer loyalty. The purpose of this research was to investigate the role of brand experience in customer satisfaction and customer loyalty in Ayandeh Bank branches in Tehran. The study employed a quantitative methodology. For data gathering, a questionnaire was utilised to measure all the variables of the research. The statistical population of the study consisted of all the customers of Ayandeh Bank branches in Tehran, and the study data was gathered from 400 respondents. The findings indicate that brand experience has a direct and meaningful impact on customer satisfaction and customer loyalty, and, furthermore, that customer satisfaction has a direct and significant effect on customer loyalty in the branches of Ayandeh Bank in Tehran.

Keywords: brand experience, customer satisfaction, customer loyalty, bank

Procedia PDF Downloads 222
934 A Conceptual Study for Investigating the Creation of Energy and Understanding the Properties of Nothing

Authors: Mahmoud Reza Hosseini

Abstract:

The universe is in a continuous expansion process, resulting in the reduction of its density and temperature. Also, by extrapolating back from its current state, the universe at its early times is studied, known as the big bang theory. According to this theory, moments after creation, the universe was an extremely hot and dense environment. However, its rapid expansion due to nuclear fusion led to a reduction in its temperature and density. This is evidenced through the cosmic microwave background and the universe structure at a large scale. However, extrapolating back further from this early state reaches singularity, which cannot be explained by modern physics, and the big bang theory is no longer valid. In addition, one can expect a nonuniform energy distribution across the universe from a sudden expansion. However, highly accurate measurements reveal an equal temperature mapping across the universe, which is contradictory to the big bang principles. To resolve this issue, it is believed that cosmic inflation occurred at the very early stages of the birth of the universe. According to the cosmic inflation theory, the elements which formed the universe underwent a phase of exponential growth due to the existence of a large cosmological constant. The inflation phase allows the uniform distribution of energy so that an equal maximum temperature can be achieved across the early universe. Also, the evidence of quantum fluctuations of this stage provides a means for studying the types of imperfections the universe would begin with. Although well-established theories such as cosmic inflation and the big bang together provide a comprehensive picture of the early universe and how it evolved into its current state, they are unable to address the singularity paradox at the time of universe creation. Therefore, a practical model capable of describing how the universe was initiated is needed. This research series aims at addressing the singularity issue by introducing a state of energy called a "neutral state," possessing an energy level that is referred to as the "base energy." The governing principles of base energy are discussed in detail in our second paper in the series "A Conceptual Study for Addressing the Singularity of the Emerging Universe," which is discussed in detail. To establish a complete picture, the origin of the base energy should be identified and studied. In this research paper, the mechanism which led to the emergence of this natural state and its corresponding base energy is proposed. In addition, the effect of the base energy in the space-time fabric is discussed. Finally, the possible role of the base energy in quantization and energy exchange is investigated. Therefore, the proposed concept in this research series provides a road map for enhancing our understating of the universe's creation from nothing and its evolution and discusses the possibility of base energy as one of the main building blocks of this universe.

Keywords: big bang, cosmic inflation, birth of universe, energy creation, universe evolution

Procedia PDF Downloads 65
933 Experimental and Analytical Dose Assessment of Patient's Family Members Treated with I-131

Authors: Marzieh Ebrahimi, Vahid Changizi, Mohammad Reza Kardan, Seyed Mahdi Hosseini Pooya, Parham Geramifar

Abstract:

Radiation exposure to the patient's family members is one of the major concerns during thyroid cancer radionuclide therapy. The aim of this study was to measure the total effective dose of the family members by means of thermoluminescence personal dosimeter, and compare with those calculated by analytical methods. Eighty-five adult family members of fifty-one patients volunteered to participate in this research study. Considering the minimum and maximum range of dose rate from 15 µsv/h to 120 µsv/h at patients' release time, the calculated mean and median dose values of family members were 0.45 mSv and 0.28 mSv, respectively. Moreover, almost all family members’ doses were measured to be less than the dose constraint of 5 mSv recommended by Basic Safety Standards. Considering the influence parameters such as patient dose rate and administrated activity, the total effective doses of family members were calculated by TEDE and NRC formulas and compared with those of experimental results. The results indicated that, it is fruitful to use the quantitative calculations for releasing patients treated with I-131 and correct estimation of patients' family doses.

Keywords: effective dose, thermoluminescence, I-131, thyroid cancer

Procedia PDF Downloads 351
932 Numerical Investigations on Group Piles’ Lateral Bearing Capacity Considering Interaction of Soil and Structure

Authors: Mahdi Sadeghian, Mahmoud Hassanlourad, Alireza Ardakani, Reza Dinarvand

Abstract:

In this research, the behavior of monopiles, under lateral loads, was investigated with vertical and oblique piles by Finite Element Method. In engineering practice when soil-pile interaction comes to the picture some simplifications are applied to reduce the design time. As a simplified replacement of soil and pile interaction analysis, pile could be replaced by a column. The height of the column would be equal to the free length of the pile plus a portion of the embedded length of it. One of the important factors studied in this study was that columns with an equivalent length (free length plus a part of buried depth) could be used instead of soil and pile modeling. The results of the analysis show that the more internal friction angle of the soil increases, the more the bearing capacity of the soil is achieved. This additional length is 6 to 11 times of the pile diameter in dense soil although in loose sandy soil this range might increase.

Keywords: Depth of fixity, Lateral bearing capacity, Oblique pile, Pile group, Soil-structure interaction

Procedia PDF Downloads 193
931 Numerical Study of Rayleight Number and Eccentricity Effect on Free Convection Fluid Flow and Heat Transfer of Annulus

Authors: Ali Reza Tahavvor‚ Saeed Hosseini, Behnam Amiri

Abstract:

Concentric and eccentric annulus is used frequently in technical and industrial applications such as nuclear reactors, thermal storage system and etc. In this paper, computational fluid dynamics (CFD) is used to investigate two dimensional free convection of laminar flow in annulus with isotherm cylinders surface and cooler inner surface. Problem studied in thirty different cases. Due to natural convection continuity and momentum equations are coupled and must be solved simultaneously. Finite volume method is used for solving governing equations. The purpose was to obtain the eccentricity effect on Nusselt number in different Rayleight numbers, so streamlines and temperature fields must be determined. Results shown that the highest Nusselt number values occurs in degree of eccentricity equal to 0.5 upward for inner cylinder and degree of eccentricity equal to 0.3 upward for outer cylinder. Side eccentricity reduces the outer cylinder Nusselt number but increases inner cylinder Nusselt number. The trend in variation of Nusselt number with respect to eccentricity remain similar in different Rayleight numbers. Correlations are included to calculate the Nusselt number of the cylinders.

Keywords: natural convection, concentric, eccentric, Nusselt number, annulus

Procedia PDF Downloads 336
930 Money as Motivation Amongst Industrial Sales People in Nigeria

Authors: Mahmoud Rufai Mahmoud

Abstract:

A look at existing literature on sales force motivation reveals lack of consensus on the role monetary rewards play in motivating salespeople. In view of the apparent contradiction inherent in the literature, it follows perhaps, chat sales managers are faced with the dilemma of what role to assign to monetary incentives in the scheme of motivating salespeople. This study investigated the perception of industrial salespeople on the role of money as a motivator. The result shows that salespeople believe that money is an important motivator whose power of motivation is influenced by a complex function of economic, social and psychological variables. Based on the findings, if is recommended that managers need different types of rewards to achieve a given level of motivation.  

Keywords: motivation, salespeople, money, Nigeria

Procedia PDF Downloads 307
929 Financial Development, FDI, and Intellectual Property on Economic Growth in Iran

Authors: Fatemeh Fahimifar, Rouhollah Nazari, Seyed Mohammad Reza Hosseini

Abstract:

Achieving an adaptable rate of economic growth has always been at the forefront of Iran development programs. In order to increase welfare level of the people in the society, all economic and social indices should be improved which is possible just in case of country's economic development and growth. While developing countries has realized the gap between developed countries and developing countries in today's world, a massive movement has been emerged in less developed countries to eliminate this economic gap. Hence this study investigates the effect of financial development, foreign direct investment and intellectual property on Iran's economic growth and taking into account other variables on economic growth such as impact of the share of foreign direct investment on GDP, government consumptive expenditure share of GDP has been paid. Period used in this study is related to the years 1974 to 2009. Also, in this research we have used Generalized Method of Moments (GMM) to examine relationship between variables. The results of this study indicate a meaningful and negative impact of financial development, the share of government consumptive expenditure to GDP and similarly, the initial GDP on economic growth. Also, the degree of economy openness, foreign direct investment and intellectual property has a meaningful positive impact on economic growth.

Keywords: financial development, FDI, intellectual property, economic growth, Iran

Procedia PDF Downloads 433
928 Prediction of Temperature Distribution during Drilling Process Using Artificial Neural Network

Authors: Ali Reza Tahavvor, Saeed Hosseini, Nazli Jowkar, Afshin Karimzadeh Fard

Abstract:

Experimental & numeral study of temperature distribution during milling process, is important in milling quality and tools life aspects. In the present study the milling cross-section temperature is determined by using Artificial Neural Networks (ANN) according to the temperature of certain points of the work piece and the points specifications and the milling rotational speed of the blade. In the present work, at first three-dimensional model of the work piece is provided and then by using the Computational Heat Transfer (CHT) simulations, temperature in different nods of the work piece are specified in steady-state conditions. Results obtained from CHT are used for training and testing the ANN approach. Using reverse engineering and setting the desired x, y, z and the milling rotational speed of the blade as input data to the network, the milling surface temperature determined by neural network is presented as output data. The desired points temperature for different milling blade rotational speed are obtained experimentally and by extrapolation method for the milling surface temperature is obtained and a comparison is performed among the soft programming ANN, CHT results and experimental data and it is observed that ANN soft programming code can be used more efficiently to determine the temperature in a milling process.

Keywords: artificial neural networks, milling process, rotational speed, temperature

Procedia PDF Downloads 372
927 Mechanical and Physical Properties of Aluminum Composite Reinforced with Carbon Nano Tube Dispersion via Ultrasonic and Ball Mill Attrition after Sever Plastic Deformation

Authors: Hassan Zare, Mohammad Jahedi, Mohammad Reza Toroghinejad, Mahmoud Meratian, Marko Knezevic

Abstract:

In this study, the carbon nanotube (CNT) reinforced Al matrix nanocomposites were fabricated by ECAP. Equal Channel Angular Pressing (ECAP) process is one of the most important methods for powder densification due to the presence of shear strain. This method samples with variety passes (one, two, four and eight passes) in C route were prepared at room temperature. A few study about metal matrix nanocomposite reinforced carbon nanotube done, the reaction intersection of interface and carbon nanotube cause to reduce the efficiency of nanocomposite. In this paper, we checked mechanical and physical properties of aluminum-CNT composite that manufactured by ECAP when the composite is deformed. The non-agglomerated CNTs were distributed homogeneously with 2% consolidation in the Aluminum matrix. The ECAP process was performed on the both monolithic and composite with distributed CNT samples for 8 passes.

Keywords: powder metallurgy, ball mill attrition, ultrasonic, consolidation

Procedia PDF Downloads 463
926 Neural Adaptive Controller for a Class of Nonlinear Pendulum Dynamical System

Authors: Mohammad Reza Rahimi Khoygani, Reza Ghasemi

Abstract:

In this paper, designing direct adaptive neural controller is applied for a class of a nonlinear pendulum dynamic system. The radial basis function (RBF) is used for the Neural network (NN). The adaptive neural controller is robust in presence of external and internal uncertainties. Both the effectiveness of the controller and robustness against disturbances are the merits of this paper. The promising performance of the proposed controllers investigates in simulation results.

Keywords: adaptive control, pendulum dynamical system, nonlinear control, adaptive neural controller, nonlinear dynamical, neural network, RBF, driven pendulum, position control

Procedia PDF Downloads 636
925 Failure Detection in an Edge Cracked Tapered Pipe Conveying Fluid Using Finite Element Method

Authors: Mohamed Gaith, Zaid Haddadin, Abdulah Wahbe, Mahmoud Hamam, Mahmoud Qunees, Mohammad Al Khatib, Mohammad Bsaileh, Abd Al-Aziz Jaber, Ahmad Aqra’a

Abstract:

The crack is one of the most common types of failure in pipelines that convey fluid, and early detection of the crack may assist to avoid the piping system from experiencing catastrophic damage, which would otherwise be fatal. The influence of flow velocity and the presence of a crack on the performance of a tapered simply supported pipe containing moving fluid is explored using the finite element approach in this study. ANSYS software is used to simulate the pipe as Bernoulli's beam theory. In this paper, the fluctuation of natural frequencies and matching mode shapes for various scenarios owing to changes in fluid speed and the presence of damage is discussed in detail.

Keywords: damage detection, finite element, tapered pipe, vibration characteristics

Procedia PDF Downloads 131
924 A Situational Awareness Map for Allocating Relief Resources after Earthquake Occurrence

Authors: Hamid Reza Ranjbar, Ali Reza Azmoude Ardalan, Hamid Dehghani, Mohammad Reza Sarajian

Abstract:

Natural disasters are unexpected events which predicting them is difficult. Earthquake is one of the most devastating disasters among natural hazards with high rate of mortality and wide extent of damages. After the earthquake occurrence, managing the critical condition and allocating limited relief sources requiring a complete awareness of damaged area. The information for allocating relief teams should be precise and reliable as much as possible, and be presented in the appropriate time after the earthquake occurrence. This type of information was previously presented in the form of a damage map; conducting relief teams by using damage map mostly lead to waste of time for finding alive occupants under the rubble. In this research, a proposed standard for prioritizing damaged buildings in terms of requiring rescue and relief was presented. This standard prioritizes damaged buildings into four levels of priority including very high, high, moderate and low by considering key parameters such as type of land use, activity time, and inactivity time of each land use, time of earthquake occurrence and distinct index. The priority map by using the proposed standard could be a basis for guiding relief teams towards the areas with high relief priority.

Keywords: Damage map, GIS, priority map, USAR

Procedia PDF Downloads 368
923 Evaluation of Immune Checkpoint Inhibitors in Cancer Therapy

Authors: Mir Mohammad Reza Hosseini

Abstract:

In new years immune checkpoint inhibitors have gathered care as being one of the greatest talented kinds of immunotherapy on the prospect. There has been a specific emphasis on the immune checkpoint molecules, cytotoxic T-lymphocyte antigen-4 (CTLA-4) and programmed cell death protein 1 (PD-1). In 2011, ipilimumab, the primary antibody obstructive an immune checkpoint (CTLA4) was authorized. It is now documented that recognized tumors have many devices of overpowering the antitumor immune response, counting manufacture of repressive cytokines, staffing of immunosuppressive immune cells, and upregulation of coinhibitory receptors recognized as immune checkpoints. This was fast followed by the growth of monoclonal antibodies directing PD1 (pembrolizumab and nivolumab) and PDL1 (atezolizumab and durvalumab). Anti-PD1/PDL1 antibodies have developed some of the greatest extensively set anticancer therapies. We also compare and difference their present place in cancer therapy and designs of immune-related toxicities and deliberate the role of dual immune checkpoint inhibition and plans for the organization of immune-related opposing proceedings. In this review, the employed code and present growth of numerous immune checkpoint inhibitors are abridged, while the communicating device and new development of Immune checkpoint inhibitors in cancer therapy-based synergistic therapies with additional immunotherapy, chemotherapy, phototherapy, and radiotherapy in important and clinical educations in the historical 5 years are portrayed and tinted. Lastly, we disapprovingly measure these methods and effort to find their fortes and faintness based on pre-clinical and clinical information.

Keywords: checkpoint, cancer therapy, PD-1, PDL-1, CTLA4, immunosuppressive

Procedia PDF Downloads 135
922 Nanofluid based on Zinc Oxide/Ferric Oxide Nanocomposite as Additive for Geothermal Drilling Fluids

Authors: Anwaar O. Ali, Mahmoud Fathy Mubarak, Mahmoud Ibrahim Abdou, Hector Cano Esteban, Amany A. Aboulrous

Abstract:

Corrosion resistance and lubrication are crucial characteristics required for geothermal drilling fluids. In this study, a ZnO/Fe₂O₃ nanocomposite was fabricated and incorporated into the structure of Cetyltrimethylammonium bromide (CTAB). Several physicochemical techniques were utilized to analyze and describe the synthesized nanomaterials. The surface morphology of the composite was assessed through scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDAX). The corrosion inhibition capabilities of these materials were explored across various corrosive environments. The weight loss and electrochemical methods were utilized to determine the corrosion inhibition activity of the prepared nanomaterials. The results demonstrate a high level of protection achieved by the composite. Additionally, the lubricant coefficient and extreme pressure properties were evaluated.

Keywords: nanofluid, corrosion, geothermal drilling fluids, ZnO/Fe2O3

Procedia PDF Downloads 23
921 Rethinking of Self-Monitoring and Self-Response Roles in Teaching Grammar Knowledge to Iranian EFL Learners

Authors: Gholam Reza Parvizi, Ali Reza Kargar, Amir Arani

Abstract:

In the present days, learning and teaching researchers have emphasized the role which teachers, tutors, and trainers’ constraint knowledge treat in resizing and trimming what they perform in educational atmosphere. Regarding English language as subject to teaching, although the prominence of instructor’s knowledge about grammar has also been stressed, but the lack of empirical insights into the relationship between teacher’ self-monitoring and self-response of grammar knowledge have been observed. With particular attention to the grammar this article indicates and discusses information obtained self- feedback and conversing teachers of a kind who backwash the issue. The result of the study indicates that enabling teachers to progress and maintain a logical and realistic awareness of their knowledge about grammar have to be prominent goal for teachers’ education and development programs.

Keywords: grammar knowledge, self-monitoring, self-response, teaching grammar, language teaching program

Procedia PDF Downloads 526
920 Microwave Absorption Properties of Low Density Polyethelene-Cobalt Ferrite Nanocomposite

Authors: Reza Fazaeli, Reza Eslami-Farsani, Hamid Targhagh

Abstract:

Low density polyethylene (LDPE) nanocomposites with 3, 5 and 7 wt. % cobalt ferrite (CoFe2O4) nanopowder fabricated with extrusion mixing and followed up by hot press to reach compact samples. The transmission/reflection measurements were carried out with a network analyzer in the frequency range of 8-12 GHz. By increasing the percent of CoFe2O4 nanopowder, reflection loss (S11) increases, while transferring loss (S21) decreases. Reflectivity (R) calculations made using S11 and S21. Increase in percent of CoFe2O4 nanopowder up to 7 wt. % in composite leaded to higher reflectivity amount, and revealed that increasing the percent of CoFe2O4 nanopowder up to 7 wt. % leads to further microwave absorption in 8-12 GHz range.

Keywords: nanocomposite, cobalt ferrite, low density polyethylene, microwave absorption

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919 Evaluation of Water-Soluble Ionic Liquids Based on Quaternized Hyperbranched Polyamidoamine and Amino Acids for Chemical Enhanced Oil Recovery

Authors: Rasha Hosny, Ahmed Zahran, Mahmoud Ramzi, Fatma Mahmoud Abdelhafiz, Ammona S. Mohamed, Mahmoud Fathy Mubarak

Abstract:

Ionic liquids' ability to be tuned and stability under challenging environmental conditions are their significant features in enhanced oil recovery. In this study, two amino acid ionic liquids (AAILs) were prepared from quaternized hyperbranched polyamidoamine PAMAM (G0.5 C12) and amino acids (Cysteine and Lysine). The chemical structures of the prepared AAILs were verified by using FTIR and 1H-NMR spectra. These AAILs were tested for solubility, thermal stability, and surface activity in the presence of Egyptian medium crude oils under different PVT parameters after being diluted in several brine solutions of various salt compositions at 10% (w/w) salinity. The measurements reveal that the produced AAILs have good solubility and thermal stability. The effect of different concentrations of AAILs (0.1-5%) and salinity (20000-70000 ppm) on Interfacial tension (IFT) were studied. To test the efficacy of (AAILs) for a CEOR, numerous flooding experiments were carried out in samples of sandstone rock. Rock wettability is important for sandstone rocks, so conduct wettability alteration by contact angle (CA) of (30-55) and IFT of (7-13). The additional oil recovery was largely influenced by ionic liquid concentration, which may be changed by dilution with the formation and injected brines. This research has demonstrated that EOR techniques led to a recovery wt. (22-45%).

Keywords: amino acid ionic liquids, surface activity, critical micelle concentration, interfacial tension, contact angle, chemical enhanced oil recovery, wettability

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918 Increasing Sustainability Using the Potential of Urban Rivers in Developing Countries with a Biophilic Design Approach

Authors: Mohammad Reza Mohammadian, Dariush Sattarzadeh, Mir Mohammad Javad Poor Hadi Hosseini

Abstract:

Population growth, urban development and urban buildup have disturbed the balance between the nature and the city, and so leading to the loss of quality of sustainability of proximity to rivers. While in the past, the sides of urban rivers were considered as urban green space. Urban rivers and their sides that have environmental, social and economic values are important to achieve sustainable development. So far, efforts have been made at various scales in various cities around the world to revitalize these areas. On the other hand, biophilic design is an innovative design approach in which attention to natural details and relation to nature is a fundamental concept. The purpose of this study is to provide an integrated framework of urban design using the potential of urban rivers (in order to increase sustainability) with a biophilic design approach to be used in cities in developing countries. The methodology of the research is based on the collection of data and information from research and projects including a study on biophilic design, investigations and projects related to the urban rivers, and a review of the literature on sustainable urban development. Then studying the boundary of urban rivers is completed by examining case samples. Eventually, integrated framework of urban design, to design the boundaries of urban rivers in the cities of developing countries is presented regarding the factors affecting the design of these areas. The result shows that according to this framework, the potential of the river banks is utilized to increase not only the environmental sustainability but also social, economic and physical stability with regard to water, light, and the usage of indigenous materials, etc.

Keywords: urban rivers, biophilic design, urban sustainability, nature

Procedia PDF Downloads 245