Search results for: Mohammad Amin Mozaheb
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1620

Search results for: Mohammad Amin Mozaheb

1320 Tribological Characterization of ZrN Coatings on Titanium Modified Austenitic Stainless Steel

Authors: Mohammad Farooq Wani

Abstract:

Tribological characterization of ZrN coatings deposited on titanium modified austenitic stainless steel (alloy D-9) substrates has been investigated. The coatings were deposited in the deposition temperature range 300–873 K, using the pulsed magnetron sputtering technique. Scratch adhesion tests were carried out using Rc indenter under various conditions of load. Detailed tribological studies were conducted to understand the friction and wear behaviour of these coatings. For all tribological studies steel and ceramic balls were used as counter face material. 3D-Surface profiles of all wear tracks was carried out using 3D universal profiler.

Keywords: ZrN, Surafce coating, thin film, tribology, friction and wear

Procedia PDF Downloads 429
1319 Numerical Study on the Hazards of Gravitational Forces on Cerebral Aneurysms

Authors: Hashem M. Alargha, Mohammad O. Hamdan, Waseem H. Aziz

Abstract:

Aerobatic and military pilots are subjected to high gravitational forces that could cause blackout, physical injuries or death. A CFD simulation using fluid-solid interactions scheme has been conducted to investigate the gravitational effects and hazards inside cerebral aneurysms. Medical data have been used to derive the size and geometry of a simple aneurysm on a T-shaped bifurcation. The results show that gravitational force has no effect on maximum Wall Shear Stress (WSS); hence, it will not cause aneurysm initiation/formation. However, gravitational force cause causes hypertension which could contribute to aneurysm rupture.

Keywords: aneurysm, cfd, wall shear stress, gravity, fluid dynamics, bifurcation artery

Procedia PDF Downloads 368
1318 Relation of Cad/Cam Zirconia Dental Implant Abutments with Periodontal Health and Final Aesthetic Aspects; A Systematic Review

Authors: Amin Davoudi

Abstract:

Aim: New approaches have been introduced to improve soft tissue indices of the dental implants. This systematic review aimed to investigate the effect of computer-aided design and computer-assisted manufacture (CAD/CAM) zirconia (Zr) implant abutments on periodontal aspects. Materials and Methods: Five electronic databases were searched thoroughly based on prior defined MeSH and non-MeSH keywords. Clinical studies were collected via hand searches in English language journals up to September 2020. Interproximal papilla stability, papilla recession, pink and white esthetic score (PES, WES), bone and gingival margin levels, color, and contour of soft tissue were reviewed. Results: The initial literature search yielded 412 articles. After the evaluation of abstracts and full texts, six studies were eligible to be screened. The study design of the included studies was a prospective cohort (n=3) and randomized clinical trial (n=3). The outcome was found to be significantly better for Zr than titanium abutments, however, the studies did not show significant differences between stock and CAD/CAM abutments. Conclusion: Papilla fill, WES, PES, and the distance from the contact point to dental crest bone of adjacent tooth and inter-tooth–implant distance were not significantly different between Zr CAD/CAM and Zr stock abutments. However, soft tissue stability and recession index were better in Zr CAD/CAM abutments.

Keywords: zirconia, CADCAM, periodental, implant

Procedia PDF Downloads 101
1317 Densities and Viscosities of Binary Mixture Containing Diethylamine and 2-Alkanol

Authors: Elham jassemi Zargani, Mohammad almasi

Abstract:

Densities and viscosities for binary mixtures of diethylamine + 2 Alkanol (2 propanol up to 2 pentanol) were measured over the entire composition range and temperature interval of 293.15 to 323.15 K. Excess molar volumes V_m^E and viscosity deviations Δη were calculated and correlated by the Redlich−Kister type function to derive the coefficients and estimate the standard error. For mixtures of diethylamine with used 2-alkanols, V_m^E and Δη are negative over the entire range of mole fraction. The observed variations of these parameters, with alkanols chain length and temperature, are discussed in terms of the inter-molecular interactions between the unlike molecules of the binary mixtures.

Keywords: densities, viscosities, diethylamine, 2-alkanol, Redlich-Kister

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1316 Wheat Production and Market in Afghanistan

Authors: Fayiz Saifurahman, Noori Fida Mohammad

Abstract:

Afghanistan produces the highest rate of wheat, it is the first source of food, and food security in Afghanistan is dependent on the availability of wheat. Although Afghanistan is the main producer of wheat, on the other hand, Afghanistan is the largest importers of flour. The objective of this study is to assess the structure and dynamics of the wheat market in Afghanistan, can compute with foreign markets, and increase the level of production. To complete this, a broad series of secondary data was complied with, group discussions and interviews with farmers, agricultural and market experts. The research findings propose that; the government should adopt different policies to support the local market. The government should distribute the seed, support financially and technically to increase wheat production.

Keywords: Afghanistan, wheat, production , import

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1315 A Low-Power Comparator Structure with Arbitrary Pre-Amplification Delay

Authors: Ata Khorami, Mohammad Sharifkhani

Abstract:

In the dynamic comparators, the pre-amplifier amplifies the input differential voltage and when the output Vcm of the pre-amplifier becomes larger than Vth of the latch input transistors, the latch is activated and finalizes the comparison. As a result, the pre-amplification delay is fixed to a value and cannot be set at the minimum required delay, thus, significant power and delay are imposed. In this paper, a novel structure is proposed through which the pre-amplification delay can be set at any low value saving power and time. Simulations show that using the proposed structure, by setting the pre-amplification delay at the minimum required value the power and comparison delay can be reduced by 55% and 100ps respectively.

Keywords: dynamic comparator, low power comparator, analog to digital converter, pre-amplification delay

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1314 Co-Immobilization of Palladium Nanoparticles and Polyoxometalate into the Cavities of the Mesocellular Foams: A Biomimetic Cooperative Catalytic System for Aerobic Oxidation of Alcohols under Green Conditions

Authors: Saeed Chehri, Sirvan Moradi, Amin Rostami

Abstract:

Cooperative catalyst systems have been developed as highly promising sustainable alternatives to traditional catalysts. In these catalysts, two or more catalytic centers cooperate to reduce the energy of chemical transformations. In nature, such systems are abundantly seen in metalloenzymes that use metal and an organic cofactor. We have designed a reusable cooperative catalyst oxidation system consisting of palladium nanoparticles and polyoxometalate. This biomimetic cooperative catalytic system was synthesized by the stepwise immobilization of palladium nanoparticlesandpolyoxometalateinto the same cavity of siliceous mesocellularfoams (Pd-POM@MCF)and wascharacterizedby SEM, EDX, FT-IR, TGAand ICP techniques. POM-Pd@MCF/HQexhibits high activity toward aerobic oxidation of alcohols to the corresponding carbonyl compoundsin water solvent at room temperature. The major novelties and advantages of this oxidation method are as follows: (i) this is the first report of the co-immobilization of polyoxometalateand palladium for use as a robust and highlyefficient heterogeneouscooperative oxidative nanocatalyst system for aerobic oxidation of alcohols, (ii) oxidation of alcoholswere performed using an ideal oxidant with good to high yields in a green solvent at ambient temperature and (iii) the immobilization of the oxygen-activating catalyst(polyoxometalate) and oxidizing catalyst (Pd) onto MCF provide practical cooperative catalyst the system that can be reused several times without a significant loss of activity (vi) the methodsconform to several of the guiding principles of green chemistry.

Keywords: palladium nanoparticles, polyoxometalate, reusable cooperative catalytic system, biomimetic oxidation reaction

Procedia PDF Downloads 118
1313 A Modified Shannon Entropy Measure for Improved Image Segmentation

Authors: Mohammad A. U. Khan, Omar A. Kittaneh, M. Akbar, Tariq M. Khan, Husam A. Bayoud

Abstract:

The Shannon Entropy measure has been widely used for measuring uncertainty. However, in partial settings, the histogram is used to estimate the underlying distribution. The histogram is dependent on the number of bins used. In this paper, a modification is proposed that makes the Shannon entropy based on histogram consistent. For providing the benefits, two application are picked in medical image processing applications. The simulations are carried out to show the superiority of this modified measure for image segmentation problem. The improvement may be contributed to robustness shown to uneven background in images.

Keywords: Shannon entropy, medical image processing, image segmentation, modification

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1312 Freedom of Information and Freedom of Expression

Authors: Amin Pashaye Amiri

Abstract:

Freedom of information, according to which the public has a right to have access to government-held information, is largely considered as a tool for improving transparency and accountability in governments, and as a requirement of self-governance and good governance. So far, more than ninety countries have recognized citizens’ right to have access to public information. This recognition often took place through the adoption of an act referred to as “freedom of information act”, “access to public records act”, and so on. A freedom of information act typically imposes a positive obligation on a government to initially and regularly release certain public information, and also obliges it to provide individuals with information they request. Such an act usually allows governmental bodies to withhold information only when it falls within a limited number of exemptions enumerated in the act such as exemptions for protecting privacy of individuals and protecting national security. Some steps have been taken at the national and international level towards the recognition of freedom of information as a human right. Freedom of information was recognized in a few countries as a part of freedom of expression, and therefore, as a human right. Freedom of information was also recognized by some international bodies as a human right. The Inter-American Court of Human Rights ruled in 2006 that Article 13 of the American Convention on Human Rights, which concerns the human right to freedom of expression, protects the right of all people to request access to government information. The European Court of Human Rights has recently taken a considerable step towards recognizing freedom of information as a human right. However, in spite of the measures that have been taken, public access to government information is not yet widely accepted as an international human right. The paper will consider the degree to which freedom of information has been recognized as a human right, and study the possibility of widespread recognition of such a human right in the future. It will also examine the possible benefits of such recognition for the development of the human right to free expression.

Keywords: freedom of information, freedom of expression, human rights, government information

Procedia PDF Downloads 548
1311 Synthesis and Characterization of Zeolite/Fe3O4 Nanocomposite Material and Investigation of Its Catalytic Reaction

Authors: Mojgan Zendehdel, Safura Molla Mohammad Zamani

Abstract:

In this paper, Fe3O4/NaY zeolite nanocomposite with different molar ratio were successfully synthesized and characterized using FT-IR, XRD, TGA, SEM and VSM techniques. The SEM graphs showed that much of Fe3O4 was successfully coated by the NaY zeolite layer. Also, the results show that the magnetism of the products is stable with added zeolite. The catalytic effect of nanocomposite investigated for esterification reaction under solvent-free conditions. Hence, the effect of the catalyst amount, reaction time, reaction temperature and reusability of catalyst were considered and nanocomposite that created from zeolite and 16.6 percent of Fe3O4 showed the highest yield. The catalyst can be easily separated from reaction with the magnet and it can also be used for several times.

Keywords: zeolite, magnetic, nanocompsite, esterification

Procedia PDF Downloads 461
1310 E-learning: An Effective Approach for Enhancing Social and Behavior Change Communication Capacity in Bangladesh

Authors: Mohammad K. Abedin, Mohammad Shahjahan, Zeenat Sultana, Tawfique Jahan, Jesmin Akter

Abstract:

To strengthen social and behavior change communication (SBCC) capacity of Ministry of Health and Family Welfare (MoHFW) of the Government of Bangladesh, BCCP/BKMI developed two eLearning courses providing opportunities for professional development of SBCC Program Managers who have no access to training or refreshers training. The two eLearning courses – Message and Material Development (MMD) and Monitoring and Evaluation (MandE) of SBCC programs – went online in September 2015, where all users could register their participation so results could be monitored. Methodology: To assess the uses of these courses a randomly selected sample was collected to run a pre and post-test analyses and a phone survey were conducted. Systematic random sampling was used to select a sample of 75 MandE and 25 MMD course participants from a sampling frame of 179 and 51 respectively. Results: As of September 2016, more than 179 learners have completed the MandE course, and 49 learners have completed the MMD course. The users of these courses are program managers, university faculty members, and students. Encouraging results were revealed from the analysis of pre and post-test scores and a phone survey three months after course completion. Test scores suggested a substantial increase in knowledge. The pre-test scores findings suggested that about 19% learners scored high on the MandE. The post-test scores finding indicated a high score (92%) of the sample across 4 modules of MandE. For MMD course in pre-test scoring, 30% of the learners scored high, and 100% scored high at the post-test. It was found that all the learners in the phone survey have discussed the courses. Most of the sharing occurred with colleagues and friends, usually through face to face (70%) interaction. The learners reported that they did recommend the two courses to concerned people. About 67% MandE and 76% MMD learners stated that the concepts that they had to learn during the course were put into practice in their work settings. The respondents for both MandE and MMD courses have provided a valuable set of suggestions that would further strengthen the courses. Conclusions: The study showed that the initiative offered ample opportunities to build capacity in various ways in which the eLearning courses were used. It also highlighted the importance of scaling up these efforts to further strengthen the outcomes.

Keywords: e-learning course, message & material development, monitoring & evaluation, social and behavior change communication

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1309 Use of Statistical Correlations for the Estimation of Shear Wave Velocity from Standard Penetration Test-N-Values: Case Study of Algiers Area

Authors: Soumia Merat, Lynda Djerbal, Ramdane Bahar, Mohammed Amin Benbouras

Abstract:

Along with shear wave, many soil parameters are associated with the standard penetration test (SPT) as a dynamic in situ experiment. Both SPT-N data and geophysical data do not often exist in the same area. Statistical analysis of correlation between these parameters is an alternate method to estimate Vₛ conveniently and without additional investigations or data acquisition. Shear wave velocity is a basic engineering tool required to define dynamic properties of soils. In many instances, engineers opt for empirical correlations between shear wave velocity (Vₛ) and reliable static field test data like standard penetration test (SPT) N value, CPT (Cone Penetration Test) values, etc., to estimate shear wave velocity or dynamic soil parameters. The relation between Vs and SPT- N values of Algiers area is predicted using the collected data, and it is also compared with the previously suggested formulas of Vₛ determination by measuring Root Mean Square Error (RMSE) of each model. Algiers area is situated in high seismic zone (Zone III [RPA 2003: réglement parasismique algerien]), therefore the study is important for this region. The principal aim of this paper is to compare the field measurements of Down-hole test and the empirical models to show which one of these proposed formulas are applicable to predict and deduce shear wave velocity values.

Keywords: empirical models, RMSE, shear wave velocity, standard penetration test

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1308 Joining of Aluminum and Steel in Car Body Manufacturing

Authors: Mohammad Mahdi Mohammadi

Abstract:

Zinc-coated steel sheets have been joined with aluminum samples in an overlapping as well as in a butt-joint configuration. A bi-metal-wire composed from aluminum and steel was used for additional welding experiments. An advantage of the laser-assisted bi-metal-wire welding is that the welding process is simplified since the primary joint between aluminium and steel exists already and laser welding occurs only between similar materials. FEM-simulations of the process were chosen to determine the ideal dimensions with respect to the formability of the bi-metal-wire. A prototype demonstrated the feasibility of the process.

Keywords: car body, steel sheets, formability of bi-metal-wire, laser-assisted bi-metal-wire

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1307 The Impact of Different Social Networks on the Development of Digital Entrepreneurship

Authors: Mohammad Mehdizadeh, Sara Miri

Abstract:

In today's world, competition is one of the essential components of different markets. Therefore, in addition to economic factors, social factors can also affect the development and prosperity of businesses. In this regard, social networks are of particular importance and play a critical role in the flourishing and development of Internet businesses. The purpose of this article is to investigate the effect of different social networks in promoting digital entrepreneurship. The research method is the descriptive survey. The results show that social networks have a positive and significant impact on digital entrepreneurship development. Among the social networks studied, Instagram and Facebook have the most positive effect on digital entrepreneurship.

Keywords: entrepreneurship, Facebook, Instagram, social media

Procedia PDF Downloads 350
1306 Investigation of Flexural – Torsion Instability of Struts Using Modified Newmark Method

Authors: Seyed Amin Vakili, Sahar Sadat Vakili, Seyed Ehsan Vakili, Nader Abdoli Yazdi

Abstract:

Differential equations are of fundamental importance in engineering and applied mathematics, since many physical laws and relations appear mathematically in the form of such equations. The equilibrium state of structures consisting of one-dimensional elements can be described by an ordinary differential equation. The response of these kinds of structures under the loading, namely relationship between the displacement field and loading field, can be predicted by the solution of these differential equations and on satisfying the given boundary conditions. When the effect of change of geometry under loading is taken into account in modeling of equilibrium state, then these differential equations are partially integrable in quartered. They also exhibit instability characteristics when the structures are loaded compressively. The purpose of this paper is to represent the ability of the Modified Newmark Method in analyzing flexural-torsional instability of struts for both bifurcation and non-bifurcation structural systems. The results are shown to be very accurate with only a small number of iterations. The method is easily programmed, and has the advantages of simplicity and speeds of convergence and easily is extended to treat material and geometric nonlinearity including no prismatic members and linear and nonlinear spring restraints that would be encountered in frames. In this paper, these abilities of the method will be extended to the system of linear differential equations that govern strut flexural torsional stability.

Keywords: instability, torsion, flexural, buckling, modified newmark method stability

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1305 Experimental Investigation on the Shear Strength Parameters of Sand-Slag Mixtures

Authors: Ayad Salih Sabbar, Amin Chegenizadeh, Hamid Nikraz

Abstract:

Utilizing waste materials in civil engineering applications has a positive influence on the environment by reducing carbon dioxide emissions and issues associated with waste disposal. Granulated blast furnace slag (GBFS) is a by-product of the iron and steel industry, with millions of tons of slag being annually produced worldwide. Slag has been widely used in structural engineering and for stabilizing clay soils; however, studies on the effect of slag on sandy soils are scarce. This article investigates the effect of slag content on shear strength parameters through direct shear tests and unconsolidated undrained triaxial tests on mixtures of Perth sand and slag. For this purpose, sand-slag mixtures, with slag contents of 2%, 4%, and 6% by weight of samples, were tested with direct shear tests under three normal stress values, namely 100 kPa, 150 kPa, and 200 kPa. Unconsolidated undrained triaxial tests were performed under a single confining pressure of 100 kPa and relative density of 80%. The internal friction angles and shear stresses of the mixtures were determined via the direct shear tests, demonstrating that shear stresses increased with increasing normal stress and the internal friction angles and cohesion increased with increasing slag. There were no significant differences in shear stresses parameters when slag content rose from 4% to 6%. The unconsolidated undrained triaxial tests demonstrated that shear strength increased with increasing slag content.

Keywords: direct shear, shear strength, slag, UU test

Procedia PDF Downloads 479
1304 Sexual Cognitive Behavioral Therapy: Psychological Performance and Openness to Experience

Authors: Alireza Monzavi Chaleshtari, Mahnaz Aliakbari Dehkordi, Amin Asadi Hieh, Majid Kazemnezhad

Abstract:

This research was conducted with the aim of determining the effectiveness of sexual cognitive behavioral therapy on psychological performance and openness to experience in women. The type of research was experimental in the form of pre-test-post-test. The statistical population of this research was made up of all working and married women with membership in the researcher's Instagram social network who had problems in marital-sexual relationships (N=900). From the statistical community, which includes working and married women who are members of the researcher's Instagram social network who have problems in marital-sexual relationships, there are 30 people including two groups (15 people in the experimental group and 15 people in the control group) as available sampling and selected randomly. They were placed in two experimental and control groups. The anxiety, stress, and depression scale (DASS) and the Costa and McCree personality questionnaire were used to collect data, and the cognitive behavioral therapy protocol of Dr. Mehrnaz Ali Akbari was used for the treatment sessions. To analyze the data, the covariance test was used in the SPSS22 software environment. The results showed that sexual cognitive behavioral therapy has a positive and significant effect on psychological performance and openness to experience in women. Conclusion: It can be concluded that interventions such as cognitive-behavioral sex can be used to treat marital problems.

Keywords: sexual cognitive behavioral therapy, psychological function, openness to experience, women

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1303 The Role of Cryptocurrency in Cross-Border Payments: A Case Study of Bangladesh

Authors: Mohammad Abdul Matin

Abstract:

This research paper aims to investigate the use of cryptocurrency in facilitating cross-border payments, with a specific focus on the case of Bangladesh. With thousands of Bangladeshi living abroad, the demand for efficient and cost-effective remittance channels is high. This paper will examine the current challenges in cross-border payments for Bangladeshi expatriates and explore the potential benefits and barriers to the adoption of cryptocurrency as a solution. Through a combination of literature review, qualitative interviews, and data analysis, the research will provide valuable insights into the opportunities and risks associated with using cryptocurrency for cross-border payments in Bangladesh.

Keywords: cryptocurrency, cross-border payments, Bangladesh, remittance, expatriates

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1302 The Mechanism of Upgrading and Urban Development in the Egyptian City: Case Study of Damietta

Authors: Lina Fayed Amin

Abstract:

The research studied, in the beginning, the related urban concepts such as the urban, development, urban development. As it also deals with the upgrading, urban upgrading, community participation and the role of local administration in development and upgrading projects. Then it studies some regional upgrading & urban development projects in Egypt followed by international projects, and the analysis the strategies followed in dealing with these projects. Afterwards, we state the regional aspects of both Damietta governorate & city, dealing with its potentials & development constraints. Followed by studying the upgrading and urban development projects strategies in reflection to the city’s crucial problems, and the constraints that faced the upgrading & development project. Then, it studied the implementation of the project’s strategies & it provided the financial resources needed for the development project in Damietta city. Followed by the studying of the urban and human development projects in the upgrading of Damietta city, as well as analyzing the different projects &analyzing the results of these projects on the aspects of the city’s needs. Then the research analysis in comparison the upgrading and urban development project in Damietta and the regional upgrading and development projects in Egypt. As well as the comparison between the upgrading and urban development project and the international projects in some Arabic and foreign countries in relation to the goals, problems, obstacles, the community participation, the finance resources and the results. Finally, it reviews the results and recommendations that were reached as a result of studying the similar urban upgrading projects in Egypt and in some Arabic and foreign countries. Followed by the analytical analysis of the upgrading and urban development in Egypt

Keywords: Damietta city, urban development, upgrading mechanisms, urban upgrading

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1301 Designing Program for Developing Self-Esteem of Gifted Children

Authors: Mohammad Jamalallail

Abstract:

Self-esteem implies a person’s overall self-worth, self-respect, and self-value. It helps a person to maintain good mental health, personality, and achievement. Gifted students face some emotional problems, sometimes, which cause decreases in their self-esteem. Such emotional problems include loneliness, anxiety, and depression as examples. For this reason, designing a counseling program is necessary for gifted students who need a high level of self-esteem. The available counseling programs focused on developmental aspect only to the best of the writer’s knowledge. While the proposed program focuses on both clinical and developmental counseling by applying psychoanalytic play therapy. The proposed program consists of; Theoretical background such as; Behavior, and RET. It also consists of counseling procedures and therapeutic interventions.

Keywords: self-esteem, gifted, program, design

Procedia PDF Downloads 428
1300 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 670
1299 Developing the Morphological Field of Problem Context to Assist Multi-Methodology in Operations Research

Authors: Mahnaz Hosseinzadeh, Mohammad Reza Mehregan

Abstract:

In this paper, we have developed a morphological field to assist multi- methodology (combining methodologies together in whole or part) in Operations Research (OR) for the problem contexts in Iranian organizations. So, we have attempted to identify some dimensions for problem context according to Iranian organizational problems. Then, a general morphological program is designed which helps the OR practitioner to determine the suitable OR methodology as output for any configuration of conditions in a problem context as input and to reveal the fields necessary to be improved in OR. Applying such a program would have interesting results for OR practitioners.

Keywords: hard, soft and emancipatory operations research, General Morphological Analysis (GMA), multi-methodology, problem context

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1298 Thermodynamic Analysis of Wet Compression Integrated with Air-Film Blade Cooling in Gas Turbine Power Plants

Authors: Hassan Athari, Alireza Ruhi Sales, Amin Pourafshar, Seyyed Mehdi Pestei, Marc. A. Rosen

Abstract:

In order to achieve high efficiency and high specific work with lower emissions, the use of advanced gas turbine cycles for power generation is useful and advantageous. Here, evaporative inlet air cooling is analyzed thermodynamically in the form of air film blade cooling of gas turbines. As the ambient temperature increases during summer months, the performance of gas turbines particularly the output power and energy efficiency are significantly decreased. The utilization of evaporative inlet cooling in gas turbine cycles increases gas turbine performance, which can assist to solve the problem in meeting the increasing demands for electrical power and offsetting shortages during peak load times. In the present research, because of the importance of turbine blade cooling, the turbine is investigated with cold compressed air used for cooling the turbine blades. The investigation of the basic and modified cycles shows that, by adding an evaporative cooler to a simple gas turbine cycle, for a turbine inlet temperature of 1400 °C, an ambient temperature of 45 °C and a relative humidity of 15%, the specific work can reach 331 (kJ/kg air), while the maximum specific work of a simple cycle for the same conditions is 273.7 (kJ/kg air). The exergy results reveal that the highest exergy destruction occurs in the combustion chamber, where the large temperature differences and highly exothermic chemical reactions are the main sources of the irreversibility.

Keywords: energy, exergy, wet compression, air-film cooling blade, gas turbine

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1297 Tolerance of Ambiguity in Relation to Listening Performance across Learners of Various Linguistic Backgrounds

Authors: Amin Kaveh Boukani

Abstract:

Foreign language learning is not straightforward and can be affected by numerous factors, among which personality features like tolerance of ambiguity (TA) are so well-known and important. Such characteristics yet can be affected by other factors like learning additional languages. The current investigation, thus, opted to explore the possible effect of linguistic background (being bilingual or trilingual) on the tolerance of ambiguity (TA) of Iranian EFL learners. Furthermore, the possible mediating effect of TA on multilingual learners' language performance (listening comprehension in this study) was expounded. This research involved 68 EFL learners (32 bilinguals, 29 trilinguals) with the age range of 19-29 doing their degrees in the Department of English Language and Literature of Urmia University. A set of questionnaires, including tolerance of ambiguity (Herman et. al., 2010) and linguistic background information (Modirkhameneh, 2005), as well as the IELTS listening comprehension test, were used for data collection purposes. The results of a set of independent samples t-test and mediation analysis (Hayes, 2022) showed that (1) linguistic background (being bilingual or trilingual) had a significant direct effect on EFL learners' TA, (2) Linguistic background had a significant direct influence on listening comprehension, (3) TA had a substantial direct influence on listening comprehension, and (4) TA moderated the influence of linguistic background on listening comprehension considerably. These results suggest that multilingualism may be considered as an advantageous asset for EFL learners and should be a prioritized characteristic in EFL instruction in multilingual contexts. Further pedagogical implications and suggestions for research are proposed in light of effective EFL instruction in multilingual contexts.

Keywords: tolerance of ambiguity, listening comprehension, multilingualism, bilingual, trilingual

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1296 The Prediction of Effective Equation on Drivers' Behavioral Characteristics of Lane Changing

Authors: Khashayar Kazemzadeh, Mohammad Hanif Dasoomi

Abstract:

According to the increasing volume of traffic, lane changing plays a crucial role in traffic flow. Lane changing in traffic depends on several factors including road geometrical design, speed, drivers’ behavioral characteristics, etc. A great deal of research has been carried out regarding these fields. Despite of the other significant factors, the drivers’ behavioral characteristics of lane changing has been emphasized in this paper. This paper has predicted the effective equation based on personal characteristics of lane changing by regression models.

Keywords: effective equation, lane changing, drivers’ behavioral characteristics, regression models

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1295 Sustainable Building Technologies for Post-Disaster Temporary Housing: Integrated Sustainability Assessment and Life Cycle Assessment

Authors: S. M. Amin Hosseini, Oriol Pons, Albert de la Fuente

Abstract:

After natural disasters, displaced people (DP) require important numbers of housing units, which have to be erected quickly due to emergency pressures. These tight timeframes can cause the multiplication of the environmental construction impacts. These negative impacts worsen the already high energy consumption and pollution caused by the building sector. Indeed, post-disaster housing, which is often carried out without pre-planning, usually causes high negative environmental impacts, besides other economic and social impacts. Therefore, it is necessary to establish a suitable strategy to deal with this problem which also takes into account the instability of its causes, like changing ratio between rural and urban population. To this end, this study aims to present a model that assists decision-makers to choose the most suitable building technology for post-disaster housing units. This model focuses on the alternatives sustainability and fulfillment of the stakeholders’ satisfactions. Four building technologies have been analyzed to determine the most sustainability technology and to validate the presented model. In 2003, Bam earthquake DP had their temporary housing units (THUs) built using these four technologies: autoclaved aerated concrete blocks (AAC), concrete masonry unit (CMU), pressed reeds panel (PR), and 3D sandwich panel (3D). The results of this analysis confirm that PR and CMU obtain the highest sustainability indexes. However, the second life scenario of THUs could have considerable impacts on the results.

Keywords: sustainability, post-disaster temporary housing, integrated value model for sustainability assessment, life cycle assessment

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1294 Alignment between Governance Structures and Food Safety Standards on the Shrimp Supply Chain in Indonesia

Authors: Maharani Yulisti, Amin Mugera, James Fogarty

Abstract:

Food safety standards have received significant attention in the fisheries global market due to health issues, free trade agreements, and increasing aquaculture production. Vertical coordination throughout the supply chain of fish producing and exporting countries is needed to meet food safety demands imposed by importing countries. However, the complexities of the supply chain governance structures and difficulties in standard implementation can generate safety uncertainty and high transaction costs. Using a Transaction Cost Economics framework, this paper examines the alignment between food safety standards and the governance structures in the shrimp supply chain in Indonesia. We find the supply chain is organized closer to the hierarchy-like governance structure where private standard (organic standard) are implemented and more towards a market-like governance structure where public standard (IndoGAP certification) are more prevalent. To verify the statements, two cases are examined from Sidoarjo district as a centre of shrimp production in Indonesia. The results show that public baseline FSS (Food Safety Standards) need additional mechanism to achieve a coordinated chain-wide response because uncertainty, asset specificity, and performance measurement problems are high in this chain. Organic standard as private chain-wide FSS is more efficient because it has been achieved by hierarchical-like type of governance structure.

Keywords: governance structure, shrimp value chain, food safety standards, transaction costs economics

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1293 Settlement of Group of Stone Columns

Authors: Adel Hanna, Tahar Ayadat, Mohammad Etezad, Cyrille Cros

Abstract:

A number of theoretical methods have been developed over the years to calculate the amount settlement of the soil reinforced with group of stone columns. The results deduced from these methods sometimes show large disagreement with the experimental observations. The reason of this divergence might be due to the fact that many of the previous methods assumed the deform shape of the columns which is different with the actual case. A new method to calculate settlement of the ground reinforced with group of stone columns is presented in this paper which overcomes the restrictions made by previous theories. This method is based on results deduced from numerical modeling. Results obtained from the model are validated.

Keywords: stone columns, group, soft soil, settlement, prediction

Procedia PDF Downloads 505
1292 The Effects of Music Therapy on Positive Negative Syndrome Scale, Cognitive Function, and Quality of Life in Female Schizophrenic Patients

Authors: Elmeida Effendy, Mustafa M. Amin, Nauli Aulia Lubis, P. J. Sirait

Abstract:

Music therapy may have an effect on mental illnesses. This is a comparative, quasi-experimental study to examine the effect of music therapy added to standard care on Positive Negative Syndrome Scale, Cognitive Function and Quality of Life in female schizophrenic patients. 50 schizophrenic participants who were diagnosed with semistructured MINI ICD-X, were assigned into two groups received pharmacotherapy. Participants were assigned into each group of therapy by using matched allocation method. Music therapy added on to the first group. They received music therapy, using Mozart Sonata four times a week, over a period of six week. Positive and negative symptoms were measured by using Positive and Negative Syndrome Scale (PANSS). Cognitive function were measured by using Mini Mental State Examination (MMSE) and Montreal Cognitive Assessment (MOCA). All rating scale were administrated by certified skill residents every week after music therapy session. The participants who were received pharmaco-and-music therapy significantly showed greater response than who received pharmacotherapy only. The mean difference of response were -6,6164 (p=0,001) for PANNS, 2,911 (p=0,004) for MMSE, 3,618 (p=0,001) for MOCA, 4,599 (p=0,001) for SF-36. Music therapy have beneficial effects on PANSS, Cognitive Function and Quality of Life in schizophrenic patients.

Keywords: music therapy, rating scale, schizophrenia, symptoms

Procedia PDF Downloads 347
1291 Production Cement Mortar and Concrete by Using Nano Clay

Authors: Mohammad Ashraf, Kawther Mohamed

Abstract:

This research tackles a new kind of additions (Nano Clay) and its effect on the features of concrete and both fresh and hardened cement mortar, as well as setting an optimal percentage of adding it to achieve the desired results and obtain on a strong concrete and mortar can be used for skyscrapers. The cementations additions are mineral materials in the form of a fine powder, added to concrete or cement mortar as partly cement substitutes, which means to be added instead of an equivalent amount of cement in order to improve and enhance some features of concrete or both the newly made and hardened cementations materials.

Keywords: nano clay in structure engineering, nanotechnology in construction industry, advanced additions in concrete, special concrete for skyscrapers

Procedia PDF Downloads 334