Search results for: Mohammad Hossein Sarrafzadeh
1307 Nonlinear Modelling of Sloshing Waves and Solitary Waves in Shallow Basins
Authors: Mohammad R. Jalali, Mohammad M. Jalali
Abstract:
The earliest theories of sloshing waves and solitary waves based on potential theory idealisations and irrotational flow have been extended to be applicable to more realistic domains. To this end, the computational fluid dynamics (CFD) methods are widely used. Three-dimensional CFD methods such as Navier-Stokes solvers with volume of fluid treatment of the free surface and Navier-Stokes solvers with mappings of the free surface inherently impose high computational expense; therefore, considerable effort has gone into developing depth-averaged approaches. Examples of such approaches include Green–Naghdi (GN) equations. In Cartesian system, GN velocity profile depends on horizontal directions, x-direction and y-direction. The effect of vertical direction (z-direction) is also taken into consideration by applying weighting function in approximation. GN theory considers the effect of vertical acceleration and the consequent non-hydrostatic pressure. Moreover, in GN theory, the flow is rotational. The present study illustrates the application of GN equations to propagation of sloshing waves and solitary waves. For this purpose, GN equations solver is verified for the benchmark tests of Gaussian hump sloshing and solitary wave propagation in shallow basins. Analysis of the free surface sloshing of even harmonic components of an initial Gaussian hump demonstrates that the GN model gives predictions in satisfactory agreement with the linear analytical solutions. Discrepancies between the GN predictions and the linear analytical solutions arise from the effect of wave nonlinearities arising from the wave amplitude itself and wave-wave interactions. Numerically predicted solitary wave propagation indicates that the GN model produces simulations in good agreement with the analytical solution of the linearised wave theory. Comparison between the GN model numerical prediction and the result from perturbation analysis confirms that nonlinear interaction between solitary wave and a solid wall is satisfactorilly modelled. Moreover, solitary wave propagation at an angle to the x-axis and the interaction of solitary waves with each other are conducted to validate the developed model.Keywords: Green–Naghdi equations, nonlinearity, numerical prediction, sloshing waves, solitary waves
Procedia PDF Downloads 2851306 The Impacts of Technology on Operations Costs: The Mediating Role of Operation Flexibility
Authors: Fazli Idris, Jihad Mohammad
Abstract:
The study aims to determine the impact of technology and service operations flexibility, which is divided into external flexibility and internal robustness, on operations costs. A mediation model is proposed that links technology to operations costs via operation flexibility. Drawing on a sample of 475 of operations managers of various service sectors in Malaysia and South Africa, Structural Equation Modeling (SEM) was employed to test the relationship using Smart-PLS procedures. It was found that a significant relationship was established between technologies to operations costs via both operations flexibility dimensions. Theoretical and managerial implications are offered to explain the results.Keywords: Operations flexibility, technology, costs, mediation
Procedia PDF Downloads 6131305 Reliability of Using Standard Penetration Test (SPT) in Evaluation of Soil Properties
Authors: Hossein Alimohammadi, Mohsen Amirmojahedi, Mehrdad Rowhani
Abstract:
Soil properties are used by geotechnical engineers to evaluate and analyze site conditions for designing purposes. Although basic soil classification tests are easy to perform and provide useful information to determine the properties of soils, it may take time to get the result and add some costs to the projects. Standard Penetration Test (SPT) provides an opportunity to evaluate soil parameters without performing laboratory tests. In addition to its simplicity and cheapness, the results become available immediately. This research provides a guideline on the application of the SPT test method, reliability of adapting the SPT test results in evaluating soil physical and mechanical properties such as Atterberg limits, shear strength, and compressive strength compressibility parameters. A total of 70 boreholes were investigated in this study by taking soil samples between depths of 1.2 to 15.25 meters. The project site was located in Morrow County, Ohio. A regression-based formula was proposed based on Tobit regression with a stepwise variable selection analysis conducted between SPT and other typical soil properties obtained from soil tests. The results of the research illustrated that the shear strength and physical properties of the soil affect the SPT number. The proposed correlation can help engineers to use SPT test results in their design with higher accuracy.Keywords: standard penetration test, soil properties, soil classification, regression method
Procedia PDF Downloads 1881304 Gene Prediction in DNA Sequences Using an Ensemble Algorithm Based on Goertzel Algorithm and Anti-Notch Filter
Authors: Hamidreza Saberkari, Mousa Shamsi, Hossein Ahmadi, Saeed Vaali, , MohammadHossein Sedaaghi
Abstract:
In the recent years, using signal processing tools for accurate identification of the protein coding regions has become a challenge in bioinformatics. Most of the genomic signal processing methods is based on the period-3 characteristics of the nucleoids in DNA strands and consequently, spectral analysis is applied to the numerical sequences of DNA to find the location of periodical components. In this paper, a novel ensemble algorithm for gene selection in DNA sequences has been presented which is based on the combination of Goertzel algorithm and anti-notch filter (ANF). The proposed algorithm has many advantages when compared to other conventional methods. Firstly, it leads to identify the coding protein regions more accurate due to using the Goertzel algorithm which is tuned at the desired frequency. Secondly, faster detection time is achieved. The proposed algorithm is applied on several genes, including genes available in databases BG570 and HMR195 and their results are compared to other methods based on the nucleotide level evaluation criteria. Implementation results show the excellent performance of the proposed algorithm in identifying protein coding regions, specifically in identification of small-scale gene areas.Keywords: protein coding regions, period-3, anti-notch filter, Goertzel algorithm
Procedia PDF Downloads 3871303 Adoption and Adoption Gap of Selected BRRI-Released Boro Rice Varieties in Bangladesh
Authors: Mohammad Abdul Momin, Sekender Ali, Mahbubul Alam, Rafiquel Islam, Mohammad Mizanul Haque Kazal
Abstract:
Improved high-yielding modern rice varieties can reduce hunger and food insecurity in Bangladesh. However, lower adoption and higher adoption gap of modern rice varieties are the main concerns of rice researchers, extension specialists, and legislators. This study attempts to determine the adoption status and adoption gap of 10 selected BRRI-released Boro rice varieties to assess some selected socio-economic characteristics of the rice farmers and to explore the contribution of the selected socio-economic characteristics of farmers to their adoption gap of selected BRRI-released Boro varieties. Necessary data were collected from 03 September to 31 December 2021 using a well-structured pre-tested interview schedule from 371 randomly selected farmers covering 12 agricultural blocks of four Upazilas under Cumilla, Mymensingh, Tangail, and Bogura districts. The study revealed that most (73.05%) of the rice farmers had high adoption and low adoption gap; 23.72% had moderate adoption and adoption gap; and the rest 3.23% of respondents’ farmers had low adoption and high adoption gap of BRRI-released Boro rice varieties. Overall adoption and adoption gap of BRRI-released Bororice varieties were 77.02% and 22.98%, respectively. Based on the descending order of the Adoption Index, BRRI dhan29 ranked 1st, followed by BRRI dhan28. The adoption indices of these two top-ranked varieties were 38.84 and 30.43, respectively, which were much higher than others. Third to ninth ranked varieties were BRRI dhan58, BRRI dhan89, BRRI dhan88, BRRI dhan50, BRRI dhan74, BRRI dhan81, and BRRI dhan63. Reverse-ranked orders were observed based on the descending order of the Adoption Gap Index (AGI). Stepwise multiple regression analysis indicated that ‘knowledge on BRRI-released Boro rice varieties’, ‘extension contacts’, ‘rice farming profitability’, ‘rice farming experience’, and ‘satisfaction on BRRI-releasedBoro rice varieties’ of the farmers had a significant negative contribution to their adoption gap, i.e., positive contribution to their adoption of BRRI-released Boro rice varieties. The study concluded that policy interventions should be taken to improve farmers’ knowledge of BRRI-releasedBoro rice varieties by increasing extension contact to all the lower and higher experienced farmers to make them profitable and satisfied to increase adoption and decrease the adoption gap of BRRI-released Boro rice varieties. These issues also urge policy interventions for the rethinking of current dissemination tactics to ensure the widespread adoption of newly released modern Boro rice varieties at the farm level.Keywords: adoption, adoption gap, Boro, rice, BRRI, Bangladesh
Procedia PDF Downloads 61302 Improving Decision-Making in Multi-Project Environments within Organizational Information Systems Using Blockchain Technology
Authors: Seyed Hossein Iranmanesh, Hassan Nouri, Seyed Reza Iranmanesh
Abstract:
In the dynamic and complex landscape of today’s business, organizations often face challenges in impactful decision-making across multi-project settings. To efficiently allocate resources, coordinate tasks, and optimize project outcomes, establishing robust decision-making processes is essential. Furthermore, the increasing importance of information systems and their integration within organizational workflows introduces an additional layer of complexity. This research proposes the use of blockchain technology as a suitable solution to enhance decision-making in multi-project environments, particularly within the realm of information systems. The conceptual framework in this study comprises four independent variables and one dependent variable. The identified independent variables for the targeted research include: Blockchain Layer in Integrated Systems, Quality of Generated Information ,User Satisfaction with Integrated Systems and Utilization of Integrated Systems. The project’s performance, considered as the dependent variable and moderated by organizational policies and procedures, reflects the impact of blockchain technology adoption on organizational effectiveness1. The results highlight the significant influence of blockchain implementation on organizational performance.Keywords: multi-project environments, decision support systems, information systems, blockchain technology, decentralized systems.
Procedia PDF Downloads 581301 Comparative Analysis of Competitive State Anxiety among Team Sport and Individual Sport Athletes in Iran
Authors: Hossein Soltani, Zahra Hojati, Seyed Reza Attarzadeh Hossini
Abstract:
Anxiety levels before and during competition are not clear due to conflicting findings; various athletes have reported different levels of anxiety from much too low. With respect to the fact that every sport field has its own special nature, and the lack of a comprehensive theory in this field made the author to compare competitive state anxiety among team sport and individual sport athletes in Iran. The sample included 120 male athletes, 60 athletes in individual sports (taekwondo, karate, and wrestling) and 60 athletes in team sports (volleyball, basketball, futsal). All participants in this study were regularly competing at the super leagues and regional level. The research instrument employed was the Persian version of the Competitive State Anxiety Inventory-2. This inventory was distributed among the subjects about 30 minutes before the first competition. Finally, using one-way ANOVA data was analyzed. The results indicated that the mean score of cognitive and somatic anxiety among individual sport athletes was higher than that of team sport athletes (P<0.05). Self-confidence levels of individual sports athletes was higher than that of team sports athletes but the difference was not significant (P >0.05). It seems the being part of a team alleviates some of the pressure experienced by those who compete alone. Conclusion: Individual sport athletes may be more exposed to evaluation and more engaged in their own skills and abilities than team sport athletes given that responsibility for performance is not distributed across several performers.Keywords: competitive state anxiety, cognitive anxiety, somatic anxiety, team sports, individual sports
Procedia PDF Downloads 5761300 How Does Ethics Impact Marketing Decision Making of a Company: An Evidence from the Telecommunication Sector of Pakistan
Authors: Mohammad Daud Ali
Abstract:
For the past decade, marketing ethics has been a central point for academic researchers and practitioners. In particular, the development of frameworks and models to help in the analysis of marketing decisions are the focus of research. The current study aims at finding whether ethical decisions (honesty, fairness, responsibility, and respect) affect organizational marketing decisions. A selection of 250 respondents was purposely made from the telecommunication industry of Pakistan, out of which 204 responses were induced at an acceptable rate of 81.6%. A five-point Likert Scale, itemized with 12 items, was adopted from Taylor-Dunlop & Lester (2000) and used to draw responses regarding ethics.Keywords: marketing, ethics, decisions making, telecommunication, Pakistan
Procedia PDF Downloads 961299 Using Digitally Reconstructed Radiographs from Magnetic Resonance Images to Localize Pelvic Lymph Nodes on 2D X-Ray Simulator-Based Brachytherapy Treatment Planning
Authors: Mohammad Ali Oghabian, Reza Reiazi, Esmaeel Parsai, Mehdi Aghili, Ramin Jaberi
Abstract:
In this project a new procedure has been introduced for utilizing digitally reconstructed radiograph from MRI images in Brachytherapy treatment planning. This procedure enables us to localize the tumor volume and delineate the extent of critical structures in vicinity of tumor volume. The aim of this project was to improve the accuracy of dose delivered to targets of interest in 2D treatment planning system.Keywords: brachytherapy, cervix, digitally reconstructed radiographs, lymph node
Procedia PDF Downloads 5301298 EEG Analysis of Brain Dynamics in Children with Language Disorders
Authors: Hamed Alizadeh Dashagholi, Hossein Yousefi-Banaem, Mina Naeimi
Abstract:
Current study established for EEG signal analysis in patients with language disorder. Language disorder can be defined as meaningful delay in the use or understanding of spoken or written language. The disorder can include the content or meaning of language, its form, or its use. Here we applied Z-score, power spectrum, and coherence methods to discriminate the language disorder data from healthy ones. Power spectrum of each channel in alpha, beta, gamma, delta, and theta frequency bands was measured. In addition, intra hemispheric Z-score obtained by scoring algorithm. Obtained results showed high Z-score and power spectrum in posterior regions. Therefore, we can conclude that peoples with language disorder have high brain activity in frontal region of brain in comparison with healthy peoples. Results showed that high coherence correlates with irregularities in the ERP and is often found during complex task, whereas low coherence is often found in pathological conditions. The results of the Z-score analysis of the brain dynamics showed higher Z-score peak frequency in delta, theta and beta sub bands of Language Disorder patients. In this analysis there were activity signs in both hemispheres and the left-dominant hemisphere was more active than the right.Keywords: EEG, electroencephalography, coherence methods, language disorder, power spectrum, z-score
Procedia PDF Downloads 4241297 Numerical Modelling of Crack Initiation around a Wellbore Due to Explosion
Authors: Meysam Lak, Mohammad Fatehi Marji, Alireza Yarahamdi Bafghi, Abolfazl Abdollahipour
Abstract:
A wellbore is a hole that is drilled to aid in the exploration and recovery of natural resources including oil and gas. Occasionally, in order to increase productivity index and porosity of the wellbore and reservoir, the well stimulation methods have been used. Hydraulic fracturing is one of these methods. Moreover, several explosions at the end of the well can stimulate the reservoir and create fractures around it. In this study, crack initiation in rock around the wellbore has been numerically modeled due to explosion. One, two, three, and four pairs of explosion have been set at the end of the wellbore on its wall. After each stage of the explosion, results have been presented and discussed. Results show that this method can initiate and probably propagate several fractures around the wellbore.Keywords: crack initiation, explosion, finite difference modelling, well productivity
Procedia PDF Downloads 2911296 The Effect of Measurement Distribution on System Identification and Detection of Behavior of Nonlinearities of Data
Authors: Mohammad Javad Mollakazemi, Farhad Asadi, Aref Ghafouri
Abstract:
In this paper, we considered and applied parametric modeling for some experimental data of dynamical system. In this study, we investigated the different distribution of output measurement from some dynamical systems. Also, with variance processing in experimental data we obtained the region of nonlinearity in experimental data and then identification of output section is applied in different situation and data distribution. Finally, the effect of the spanning the measurement such as variance to identification and limitation of this approach is explained.Keywords: Gaussian process, nonlinearity distribution, particle filter, system identification
Procedia PDF Downloads 5161295 Thermal Comfort in Office Rooms in a Historic Building with Modernized Heating, Ventilation and Air Conditioning Systems
Authors: Hossein Bakhtiari, Mathias Cehlin, Jan Akander
Abstract:
Envelopes with low thermal performance is a common characteristic in many European historic buildings which leads to higher energy demand for heating and cooling as well as insufficient thermal comfort for the occupants. This paper presents the results of a study on the thermal comfort in the City Hall (Rådhuset) in Gävle, Sweden. This historic building is currently used as an office building. It is equipped with two relatively modern mechanical heat recovery ventilation systems with displacement ventilation supply devices in the offices. The district heating network heats the building via pre-heat supply air and radiators. Summer cooling comes from an electric heat pump that rejects heat into the exhaust ventilation air. A building management system controls HVAC equipment (heating, ventilation and air conditioning). The methodology is based on on-site measurements, data logging on the management system and evaluating the occupants’ perception of a summer and a winter period indoor environment using a standardized questionnaire. The main aim of the study is to investigate whether or not it is enough to have modernized HVAC systems to get adequate thermal comfort in a historic building with poor envelope performance used as an office building in Nordic climate conditions.Keywords: historic buildings, on-site measurements, standardized questionnaire, thermal comfort
Procedia PDF Downloads 3741294 The Evaluation of the Performance of Different Filtering Approaches in Tracking Problem and the Effect of Noise Variance
Authors: Mohammad Javad Mollakazemi, Farhad Asadi, Aref Ghafouri
Abstract:
Performance of different filtering approaches depends on modeling of dynamical system and algorithm structure. For modeling and smoothing the data the evaluation of posterior distribution in different filtering approach should be chosen carefully. In this paper different filtering approaches like filter KALMAN, EKF, UKF, EKS and smoother RTS is simulated in some trajectory tracking of path and accuracy and limitation of these approaches are explained. Then probability of model with different filters is compered and finally the effect of the noise variance to estimation is described with simulations results.Keywords: Gaussian approximation, Kalman smoother, parameter estimation, noise variance
Procedia PDF Downloads 4391293 The Role of Critical Thinking in Disease Diagnosis: A Comprehensive Review
Authors: Mohammad Al-Mousawi
Abstract:
This academic article explores the indispensable role of critical thinking in the process of diagnosing diseases. Employing a multidisciplinary approach, we delve into the cognitive skills and analytical mindset that clinicians, researchers, and healthcare professionals must employ to navigate the complexities of disease identification. By examining the integration of critical thinking within the realms of medical education, diagnostic decision-making, and technological advancements, this article aims to underscore the significance of cultivating and applying critical thinking skills in the ever-evolving landscape of healthcare.Keywords: critical thinking, medical education, diagnostic decision-making, fostering critical thinking
Procedia PDF Downloads 741292 Cold Flow Investigation of Silicon Carbide Cylindrical Filter Element
Authors: Mohammad Alhajeri
Abstract:
This paper reports a computational fluid dynamics (CFD) investigation of cylindrical filter. Silicon carbide cylindrical filter elements have proven to be an effective mean of removing particulates to levels exceeding the new source performance standard. The CFD code is used here to understand the deposition process and the factors that affect the particles distribution over the filter element surface. Different approach cross flow velocity to filter face velocity ratios and different face velocities (ranging from 2 to 5 cm/s) are used in this study. Particles in the diameter range 1 to 100 microns are tracked through the domain. The radius of convergence (or the critical trajectory) is compared and plotted as a function of many parameters.Keywords: filtration, CFD, CCF, hot gas filtration
Procedia PDF Downloads 4611291 Artificial Intelligence Aided Improvement in Canada's Supply Chain Management
Authors: Mohammad Talebi
Abstract:
Supply chain administration could be a concern for all the countries within the world, whereas there's no special approach towards supportability. Generally, for one decade, manufactured insights applications in keen supply chains have found a key part. In this paper, applications of artificial intelligence in supply chain management have been clarified, and towards Canadian plans for smart supply chain management (SCM), a few notes have been suggested. A hierarchical framework for smart SCM might provide a great roadmap for decision-makers to find the most appropriate approach toward smart SCM. Within the system of decision-making, all the levels included in the accomplishment of smart SCM are included. In any case, more considerations are got to be paid to available and needed infrastructures.Keywords: smart SCM, AI, SSCM, procurement
Procedia PDF Downloads 881290 The Relationship between Value-Added and Energy Consumption in Iran’s Industry Sector
Authors: Morteza Raei Dehaghi, Mojtaba Molaahmadi, Seyed Mohammad Mirhashemi
Abstract:
This study aimed to explore the relationship between energy consumption and value-added in Iran’s industry sector during the time period 1973-2011. Annual data related to energy consumption and value added in the industry sector were used. The results of the study revealed a positive relationship between energy consumption and value-added of the industry sector. Similarly, the results showed that there is one-way causality between energy consumption and value-added in the industry sector.Keywords: economic growth, energy consumption, granger causality test, industry sector
Procedia PDF Downloads 4821289 Wind Power Forecasting Using Echo State Networks Optimized by Big Bang-Big Crunch Algorithm
Authors: Amir Hossein Hejazi, Nima Amjady
Abstract:
In recent years, due to environmental issues traditional energy sources had been replaced by renewable ones. Wind energy as the fastest growing renewable energy shares a considerable percent of energy in power electricity markets. With this fast growth of wind energy worldwide, owners and operators of wind farms, transmission system operators, and energy traders need reliable and secure forecasts of wind energy production. In this paper, a new forecasting strategy is proposed for short-term wind power prediction based on Echo State Networks (ESN). The forecast engine utilizes state-of-the-art training process including dynamical reservoir with high capability to learn complex dynamics of wind power or wind vector signals. The study becomes more interesting by incorporating prediction of wind direction into forecast strategy. The Big Bang-Big Crunch (BB-BC) evolutionary optimization algorithm is adopted for adjusting free parameters of ESN-based forecaster. The proposed method is tested by real-world hourly data to show the efficiency of the forecasting engine for prediction of both wind vector and wind power output of aggregated wind power production.Keywords: wind power forecasting, echo state network, big bang-big crunch, evolutionary optimization algorithm
Procedia PDF Downloads 5721288 Variation of Airfoil Pressure Profile Due to Confined Air Streams: Application in Gas-Oil Separators
Authors: Amir Hossein Haji, Nabeel Al-Rawahi, Gholamreza Vakili-Nezhaad
Abstract:
An innovative design has been examined for a gas-oil separator based on pressure reduction over an airfoil surface. The primary motivations are to shorten the release trajectory of the bubbles by minimizing the thickness of the oil layer as well as improving uniform pressure reduction zones. Restricted airflow over an airfoil is investigated for its effect on the pressure drop enhancement and the maximum attainable attack angle prior to the stall condition. Aerodynamic separation is delayed based on numerical simulation of Wortmann FX 63137 Airfoil in a confined domain using FLUENT 6.3.26. The proposed set up results in higher pressure drop compared with the free stream case. With the aim of optimum power consumption we have pursued further restriction to an air jet case over the airfoil. Then, a curved strip model is suggested for the air jet which can be applied as an analysis/design tool for the best performance conditions. Pressure reduction is shown to be inversely proportional to the curvature of the upper airfoil profile. This reduction occurs within the tracking zones where the air jet is effectively attached to the airfoil surface. The zero slope condition is suggested to estimate the onset of these zones after which the minimum curvature should be searched. The corresponding zero slope curvature is applied for estimation of the maximum pressure drop which shows satisfactory agreement with the simulation results.Keywords: airfoil, air jet, curved fluid flow, gas-oil separator
Procedia PDF Downloads 4721287 Numerical Investigation of AL₂O₃ Nanoparticle Effect on a Boiling Forced Swirl Flow Field
Authors: Ataollah Rabiee1, Amir Hossein Kamalinia, Alireza Atf
Abstract:
One of the most important issues in the design of nuclear fusion power plants is the heat removal from the hottest region at the diverter. Various methods could be employed in order to improve the heat transfer efficiency, such as generating turbulent flow and injection of nanoparticles in the host fluid. In the current study, Water/AL₂O₃ nanofluid forced swirl flow boiling has been investigated by using a homogeneous thermophysical model within the Eulerian-Eulerian framework through a twisted tape tube, and the boiling phenomenon was modeled using the Rensselaer Polytechnic Institute (RPI) approach. In addition to comparing the results with the experimental data and their reasonable agreement, it was evidenced that higher flow mixing results in more uniform bulk temperature and lower wall temperature along the twisted tape tube. The presence of AL₂O₃ nanoparticles in the boiling flow field showed that increasing the nanoparticle concentration leads to a reduced vapor volume fraction and wall temperature. The Computational fluid dynamics (CFD) results show that the average heat transfer coefficient in the tube increases both by increasing the nanoparticle concentration and the insertion of twisted tape, which significantly affects the thermal field of the boiling flow.Keywords: nanoparticle, boiling, CFD, two phase flow, alumina, ITER
Procedia PDF Downloads 1251286 Experimental Investigation on Effect of Different Heat Treatments on Phase Transformation and Superelasticity of NiTi Alloy
Authors: Erfan Asghari Fesaghandis, Reza Ghaffari Adli, Abbas Kianvash, Hossein Aghajani, Homa Homaie
Abstract:
NiTi alloys possess magnificent superelastic, shape memory, high strength and biocompatible properties. For improving mechanical properties, foremost, superelasticity behavior, heat treatment process is carried out. In this paper, two different heat treatment methods were undertaken: (1) solid solution, and (2) aging. The effect of each treatment in a constant time is investigated. Five samples were prepared to study the structure and optimize mechanical properties under different time and temperature. For measuring the upper plateau stress, lower plateau stress and residual strain, tensile test is carried out. The samples were aged at two different temperatures to see difference between aging temperatures. The sample aged at 500 °C has a bigger crystallite size and lower amount of Ni which causes the mentioned sample to possess poor pseudo elasticity behaviour than the other aged sample. The sample aged at 460 °C has shown remarkable superelastic properties. The mentioned sample’s higher plateau is 580 MPa with the lowest residual strain (0.17%) while other samples have possessed higher residual strains. X-ray diffraction was used to investigate the produced phases.Keywords: heat treatment, phase transformation, superelasticity, NiTi alloy
Procedia PDF Downloads 1301285 Modelling Soil Inherent Wind Erodibility Using Artifical Intellligent and Hybrid Techniques
Authors: Abbas Ahmadi, Bijan Raie, Mohammad Reza Neyshabouri, Mohammad Ali Ghorbani, Farrokh Asadzadeh
Abstract:
In recent years, vast areas of Urmia Lake in Dasht-e-Tabriz has dried up leading to saline sediments exposure on the surface lake coastal areas being highly susceptible to wind erosion. This study was conducted to investigate wind erosion and its relevance to soil physicochemical properties and also modeling of wind erodibility (WE) using artificial intelligence techniques. For this purpose, 96 soil samples were collected from 0-5 cm depth in 414000 hectares using stratified random sampling method. To measure the WE, all samples (<8 mm) were exposed to 5 different wind velocities (9.5, 11, 12.5, 14.1 and 15 m s-1 at the height of 20 cm) in wind tunnel and its relationship with soil physicochemical properties was evaluated. According to the results, WE varied within the range of 76.69-9.98 (g m-2 min-1)/(m s-1) with a mean of 10.21 and coefficient of variation of 94.5% showing a relatively high variation in the studied area. WE was significantly (P<0.01) affected by soil physical properties, including mean weight diameter, erodible fraction (secondary particles smaller than 0.85 mm) and percentage of the secondary particle size classes 2-4.75, 1.7-2 and 0.1-0.25 mm. Results showed that the mean weight diameter, erodible fraction and percentage of size class 0.1-0.25 mm demonstrated stronger relationship with WE (coefficients of determination were 0.69, 0.67 and 0.68, respectively). This study also compared efficiency of multiple linear regression (MLR), gene expression programming (GEP), artificial neural network (MLP), artificial neural network based on genetic algorithm (MLP-GA) and artificial neural network based on whale optimization algorithm (MLP-WOA) in predicting of soil wind erodibility in Dasht-e-Tabriz. Among 32 measured soil variable, percentages of fine sand, size classes of 1.7-2.0 and 0.1-0.25 mm (secondary particles) and organic carbon were selected as the model inputs by step-wise regression. Findings showed MLP-WOA as the most powerful artificial intelligence techniques (R2=0.87, NSE=0.87, ME=0.11 and RMSE=2.9) to predict soil wind erodibility in the study area; followed by MLP-GA, MLP, GEP and MLR and the difference between these methods were significant according to the MGN test. Based on the above finding MLP-WOA may be used as a promising method to predict soil wind erodibility in the study area.Keywords: wind erosion, erodible fraction, gene expression programming, artificial neural network
Procedia PDF Downloads 711284 Time Estimation of Return to Sports Based on Classification of Health Levels of Anterior Cruciate Ligament Using a Convolutional Neural Network after Reconstruction Surgery
Authors: Zeinab Jafari A., Ali Sharifnezhad B., Mohammad Razi C., Mohammad Haghpanahi D., Arash Maghsoudi
Abstract:
Background and Objective: Sports-related rupture of the anterior cruciate ligament (ACL) and following injuries have been associated with various disorders, such as long-lasting changes in muscle activation patterns in athletes, which might last after ACL reconstruction (ACLR). The rupture of the ACL might result in abnormal patterns of movement execution, extending the treatment period and delaying athletes’ return to sports (RTS). As ACL injury is especially prevalent among athletes, the lengthy treatment process and athletes’ absence from sports are of great concern to athletes and coaches. Thus, estimating safe time of RTS is of crucial importance. Therefore, using a deep neural network (DNN) to classify the health levels of ACL in injured athletes, this study aimed to estimate the safe time for athletes to return to competitions. Methods: Ten athletes with ACLR and fourteen healthy controls participated in this study. Three health levels of ACL were defined: healthy, six-month post-ACLR surgery and nine-month post-ACLR surgery. Athletes with ACLR were tested six and nine months after the ACLR surgery. During the course of this study, surface electromyography (sEMG) signals were recorded from five knee muscles, namely Rectus Femoris (RF), Vastus Lateralis (VL), Vastus Medialis (VM), Biceps Femoris (BF), Semitendinosus (ST), during single-leg drop landing (SLDL) and forward hopping (SLFH) tasks. The Pseudo-Wigner-Ville distribution (PWVD) was used to produce three-dimensional (3-D) images of the energy distribution patterns of sEMG signals. Then, these 3-D images were converted to two-dimensional (2-D) images implementing the heat mapping technique, which were then fed to a deep convolutional neural network (DCNN). Results: In this study, we estimated the safe time of RTS by designing a DCNN classifier with an accuracy of 90 %, which could classify ACL into three health levels. Discussion: The findings of this study demonstrate the potential of the DCNN classification technique using sEMG signals in estimating RTS time, which will assist in evaluating the recovery process of ACLR in athletes.Keywords: anterior cruciate ligament reconstruction, return to sports, surface electromyography, deep convolutional neural network
Procedia PDF Downloads 781283 Synthesis and Biological Activity Evaluation of U Complexes
Authors: Mohammad Kazem Mohammadi
Abstract:
The use of anticancer agents forms an important part of the treatment of cancer of various types. Uranyl Complexes with DPHMP ligand have been used for the prevention and treatment of cancers. U(IV) metal complexes prepared by reaction of uranyl salt UO2 (NO3)2.6H2O with DPHMP in dry acetonitrile. Characterization of the ligand and its complexes was made by microanalyses, FT-IR, 1H NMR, 13C NMR and UV–Visible spectroscopy. These new complex showed excellent antitumor activity against two kinds of cancer cells that that are HT29:Haman colon adenocarcinoma cell line and T47D:human breast adenocarcinoma cell line.Keywords: uranyl complexes, DPHMP ligand, antitumor activity, HT29, T47D
Procedia PDF Downloads 4701282 Dialogue, Agency and Appropriation in Peer Interactions
Authors: Mohammad Naseh Nasrollahi Shahri
Abstract:
The article draws on Michael Bakhtin’s theory of language to examine peer interactions. It represents an analysis of other-repetition in student interactions. Several recent studies have explored various aspects of repetition in multiple contexts. However, other-repetition in peer interactions has not received enough attention. Building on previous studies, this study examines patterns of other-repetition or appropriation in the context of discussion activities performed by EFL learners. The analysis highlights the meaningfulness of other-repetition in a way that distinguishes them from rote-repetition. It is suggested that instances of repetition constitute third spaces between the self and other which provide ideal settings for language learning and demonstrate student agency and engagement.Keywords: repetition, agency, Bakhtin, dialogue
Procedia PDF Downloads 6331281 Hepatitis B Prevalence in Institutionalized Intellectually Disabled Children
Authors: Maryam Vaezjalali, Foad Davoodbeglou, Mehrnaz Mesdaghi, Hossein Goudarzi, Fariba Shojaei, Hourieh Aram
Abstract:
Introduction: Hepatitis B virus (HBV) infection causes chronic infection in human population, with high mortality. Some people are more susceptible to this infection. One of the high risk communities is mentally retarded children, who are institutionalized. Special conditions in these centers predispose children for HBV infection and transmission to healthy people. In this study our objective was to determine the prevalence of HBV infection among institutionalized mentally retarded children and study its associated risk factors. Materials and methods: In this study, 250 mentally retarded children (younger than 14 years old) were included. They were living in 5 nursing institutions, located in different parts of Tehran. HBsAg was measured in the sera of these patients by ELISA method. Results: Among 250 children, 20 children (8%) were HBsAg positive. HBV infection in girls was more than boys (11% to 5.6%). Among the types of mental retardation, children with cerebral palsy had the highest positive result for HBsAg. The most HBV infection (28.5%) was seen in children with longest duration of being institutionalized (10 to 11 years). Vaccinated children were more HBsAg positive (8.7%) than non-vaccinated children (5.3%). However, no significant relationship was observed between any of these factors and HBsAg positivity. Conclusion: Despite improvement of people’s health condition and implementation of HBV vaccination, the prevalence of HBV infection is high in institutionalized mentally retarded children, which highlights the need for active measures to reduce this infection among this high risk population.Keywords: hepatitis B virus, HBV vaccine, intellectually disabled children, mentally retarded
Procedia PDF Downloads 4821280 A Machine Learning-Assisted Crime and Threat Intelligence Hunter
Authors: Mohammad Shameel, Peter K. K. Loh, James H. Ng
Abstract:
Cybercrime is a new category of crime which poses a different challenge for crime investigators and incident responders. Attackers can mask their identities using a suite of tools and with the help of the deep web, which makes them difficult to track down. Scouring the deep web manually takes time and is inefficient. There is a growing need for a tool to scour the deep web to obtain useful evidence or intel automatically. In this paper, we will explain the background and motivation behind the research, present a survey of existing research on related tools, describe the design of our own crime/threat intelligence hunting tool prototype, demonstrate its capability with some test cases and lastly, conclude with proposals for future enhancements.Keywords: cybercrime, deep web, threat intelligence, web crawler
Procedia PDF Downloads 1731279 Effects of Position and Shape of Atomic Defects on the Band Gap of Graphene Nano-Ribbon Superlattices
Authors: Zeinab Jokar, Mohammad Reza Moslemi
Abstract:
In this work, we study the behavior of introducing atomic size vacancy in a graphene nanoribbon superlattice. Our investigations are based on the density functional theory (DFT) with the Local Density Approximation in Atomistix Toolkit (ATK). We show that, in addition to its shape, the position of vacancy has a major impact on the electrical properties of a graphene nanoribbon superlattice. We show that the band gap of an armchair graphene nanoribbon may be tuned by introducing an appropriate periodic pattern of vacancies. The band gap changes in a zig-zag manner similar to the variation of the band gap of a graphene nanoribbon by changing its width.Keywords: AGNR, antidot, atomistic toolKit, vacancy
Procedia PDF Downloads 10061278 Cloud Computing in Jordanian Libraries: An Overview
Authors: Mohammad A. Al-Madi, Nagham A. Al-Madi, Fanan A. Al-Madi
Abstract:
The current concept of the technology of cloud computing libraries has been increasing where users can store their data in a virtual space and can be retrieved from anywhere whilst using the network. By using cloud computing technology, industries and individuals save money, time, and space. Moreover, data and information about libraries can be placed in the cloud. This paper discusses the meaning of cloud computing along with its types. Further, the focus has been given to the application of cloud computing in modern libraries. Additionally, the advantages of cloud computing and the areas in which cloud computing be applied with current usage are discussed. Finally, the present situation of the Jordanian libraries is considered and discussed in further detail.Keywords: cloud computing, community cloud, hybrid cloud, private cloud, public cloud
Procedia PDF Downloads 221