Search results for: Razieh Jafari Hajati
18 Theoretical Analysis and Design Consideration of Screened Heat Pipes for Low-Medium Concentration Solar Receivers
Authors: Davoud Jafari, Paolo Di Marco, Alessandro Franco, Sauro Filippeschi
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This paper summarizes the results of an investigation into the heat pipe heat transfer for solar collector applications. The study aims to show the feasibility of a concentrating solar collector, which is coupled with a heat pipe. Particular emphasis is placed on the capillary and boiling limits in capillary porous structures, with different mesh numbers and wick thicknesses. A mathematical model of a cylindrical heat pipe is applied to study its behaviour when it is exposed to higher heat input at the evaporator. The steady state analytical model includes two-dimensional heat conduction in the HP’s wall, the liquid flow in the wick and vapor hydrodynamics. A sensitivity analysis was conducted by considering different design criteria and working conditions. Different wicks (mesh 50, 100, 150, 200, 250, and, 300), different porosities (0.5, 0.6, 0.7, 0.8, and 0.9) with different wick thicknesses (0.25, 0.5, 1, 1.5, and 2 mm) are analyzed with water as a working fluid. Results show that it is possible to improve heat transfer capability (HTC) of a HP by selecting the appropriate wick thickness, the effective pore radius, and lengths for a given HP configuration, and there exist optimal design criteria (optimal thick, evaporator adiabatic and condenser sections). It is shown that the boiling and wicking limits are connected and occurs in dependence on each other. As different parts of the HP external surface collect different fractions of the total incoming insolation, the analysis of non-uniform heat flux distribution indicates that peak heat flux is not affecting parameter. The parametric investigations are aimed to determine working limits and thermal performance of HP for medium temperature SC application.Keywords: screened heat pipes, analytical model, boiling and capillary limits, concentrating collector
Procedia PDF Downloads 55817 Investigation of Boll Properties on Cotton Picker Machine Performance
Authors: Shahram Nowrouzieh, Abbas Rezaei Asl, Mohamad Ali Jafari
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Cotton, as a strategic crop, plays an important role in providing human food and clothing need, because of its oil, protein, and fiber. Iran has been one of the largest cotton producers in the world in the past, but unfortunately, for economic reasons, its production is reduced now. One of the ways to reduce the cost of cotton production is to expand the mechanization of cotton harvesting. Iranian farmers do not accept the function of cotton harvesters. One reason for this lack of acceptance of cotton harvesting machines is the number of field losses on these machines. So, the majority of cotton fields are harvested by hand. Although the correct setting of the harvesting machine is very important in the cotton losses, the morphological properties of the cotton plant also affect the performance of cotton harvesters. In this study, the effect of some cotton morphological properties such as the height of the cotton plant, number, and length of sympodial and monopodial branches, boll dimensions, boll weight, number of carpels and bracts angle were evaluated on the performance of cotton picker. In this research, the efficiency of John Deere 9920 spindle Cotton picker is investigated on five different Iranian cotton cultivars. The results indicate that there was a significant difference between the five cultivars in terms of machine harvest efficiency. Golestan cultivar showed the best cotton harvester performance with an average of 87.6% of total harvestable seed cotton and Khorshid cultivar had the least cotton harvester performance. The principal component analysis showed that, at 50.76% probability, the cotton picker efficiency is affected by the bracts angle positively and by boll dimensions, the number of carpels and the height of cotton plants negatively. The seed cotton remains (in the plant and on the ground) after harvester in PCA scatter plot were in the same zone with boll dimensions and several carpels.Keywords: cotton, bract, harvester, carpel
Procedia PDF Downloads 13516 Plant Growth and Yield Enhancement of Soybean by Inoculation with Symbiotic and Nonsymbiotic Bacteria
Authors: Timea I. Hajnal-Jafari, Simonida S. Đurić, Dragana R. Stamenov
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Microbial inoculants from the group of symbiotic-nitrogen-fixing rhizobia are well known and widely used in production of legumes. On the other hand, nonsymbiotic plant growth promoting rhizobacteria (PGPR) are not commonly used in practice. The objective of this study was to examine the effects of soybean inoculation with symbiotic and nonsymbiotic bacteria on plant growth and seed yield of soybean. Microbiological activity in rhizospheric soil was also determined. The experiment was set up using a randomized block system in filed conditions with the following treatments: control-no inoculation; treatment 1-Bradyrhizobium japonicum; treatment 2-Azotobacter sp.; treatment 3-Bacillus sp..In the flowering stage of growth (FS) the number of nodules per plant (NPP), root length (RL), plant height (PH) and weight (PW) were measured. The number of pod per plant (PPP), number of seeds per pod (SPP) and seed weight per plant (SWP) were recorded at the end of vegetation period (EV). Microbiological analyses of soil included the determination of total number of bacteria (TNB), number of fungi (FNG), actinomycetes (ACT) and azotobacters (AZB) as well as the activity of the dehydrogenase enzyme (DHA). The results showed that bacterial inoculation led to the formation of root nodules regardless of the treatments with statistically no significant difference. Strong nodulation was also present in control treatment. RL and PH were positively influenced by inoculation with Azotobacter sp. and Bacillus sp., respectively. Statistical analyses of the number of PPP, SPP, and SWP showed no significant differences among investigated treatments. High average number of microorganisms were determined in all treatments. Most abundant were TNB (log No 8,010) and ACT (log No 6,055) than FNG and AZB with log No 4,867 and log No 4,025, respectively. The highest DHA activity was measured in the FS of soybean in treatment 3. The application of nonsymbiotic bacteria in soybean production can alleviate initial plant growth and help the plant to better overcome different stress conditions caused by abiotic and biotic factors.Keywords: bacteria, inoculation, soybean, microbial activity
Procedia PDF Downloads 15115 The Effectiveness of Teaching Emotional Intelligence on Reducing Marital Conflicts and Marital Adjustment in Married Students of Tehran University
Authors: Elham Jafari
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The aim of this study was to evaluate the effectiveness of emotional intelligence training on reducing marital conflict and marital adjustment in married students of the University of Tehran. This research is an applied type in terms of purpose and a semi-experimental design of pre-test-post-test type with the control group and with follow-up test in terms of the data collection method. The statistical population of the present study consisted of all married students of the University of Tehran. In this study, 30 married students of the University of Tehran were selected by convenience sampling method as a sample that 15 people in the experimental group and 15 people in the control group were randomly selected. The method of data collection in this research was field and library. The data collection tool in the field section was two questionnaires of marital conflict and marital adjustment. To analyze the collected data, first at the descriptive level, using statistical indicators, the demographic characteristics of the sample were described by SPSS software. In inferential statistics, the statistical method used was the test of analysis of covariance. The results showed that the effect of the independent variable of emotional intelligence on the reduction of marital conflicts is statistically significant. And it can be inferred that emotional intelligence training has reduced the marital conflicts of married students of the University of Tehran in the experimental group compared to the control group. Also, the effect of the independent variable of emotional intelligence on marital adjustment was statistically significant. It can be inferred that emotional intelligence training has adjusted the marital adjustment of married students of the University of Tehran in the experimental group compared to the control group.Keywords: emotional intelligence, marital conflicts, marital compatibility, married students
Procedia PDF Downloads 25114 An Experimental Investigation of the Surface Pressure on Flat Plates in Turbulent Boundary Layers
Authors: Azadeh Jafari, Farzin Ghanadi, Matthew J. Emes, Maziar Arjomandi, Benjamin S. Cazzolato
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The turbulence within the atmospheric boundary layer induces highly unsteady aerodynamic loads on structures. These loads, if not accounted for in the design process, will lead to structural failure and are therefore important for the design of the structures. For an accurate prediction of wind loads, understanding the correlation between atmospheric turbulence and the aerodynamic loads is necessary. The aim of this study is to investigate the effect of turbulence within the atmospheric boundary layer on the surface pressure on a flat plate over a wide range of turbulence intensities and integral length scales. The flat plate is chosen as a fundamental geometry which represents structures such as solar panels and billboards. Experiments were conducted at the University of Adelaide large-scale wind tunnel. Two wind tunnel boundary layers with different intensities and length scales of turbulence were generated using two sets of spires with different dimensions and a fetch of roughness elements. Average longitudinal turbulence intensities of 13% and 26% were achieved in each boundary layer, and the longitudinal integral length scale within the three boundary layers was between 0.4 m and 1.22 m. The pressure distributions on a square flat plate at different elevation angles between 30° and 90° were measured within the two boundary layers with different turbulence intensities and integral length scales. It was found that the peak pressure coefficient on the flat plate increased with increasing turbulence intensity and integral length scale. For example, the peak pressure coefficient on a flat plate elevated at 90° increased from 1.2 to 3 with increasing turbulence intensity from 13% to 26%. Furthermore, both the mean and the peak pressure distribution on the flat plates varied with turbulence intensity and length scale. The results of this study can be used to provide a more accurate estimation of the unsteady wind loads on structures such as buildings and solar panels.Keywords: atmospheric boundary layer, flat plate, pressure coefficient, turbulence
Procedia PDF Downloads 13813 LaeA/1-Velvet Interplay in Aspergillus and Trichoderma: Regulation of Secondary Metabolites and Cellulases
Authors: Razieh Karimi Aghcheh, Christian Kubicek, Joseph Strauss, Gerhard Braus
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Filamentous fungi are of considerable economic and social significance for human health, nutrition and in white biotechnology. These organisms are dominant producers of a range of primary metabolites such as citric acid, microbial lipids (biodiesel) and higher unsaturated fatty acids (HUFAs). In particular, they produce also important but structurally complex secondary metabolites with enormous therapeutic applications in pharmaceutical industry, for example: cephalosporin, penicillin, taxol, zeranol and ergot alkaloids. Several fungal secondary metabolites, which are significantly relevant to human health do not only include antibiotics, but also e.g. lovastatin, a well-known antihypercholesterolemic agent produced by Aspergillus. terreus, or aflatoxin, a carcinogen produced by A. flavus. In addition to their roles for human health and agriculture, some fungi are industrially and commercially important: Species of the ascomycete genus Hypocrea spp. (teleomorph of Trichoderma) have been demonstrated as efficient producer of highly active cellulolytic enzymes. This trait makes them effective in disrupting and depolymerization of lignocellulosic materials and thus applicable tools in number of biotechnological areas as diverse as clothes-washing detergent, animal feed, and pulp and fuel productions. Fungal LaeA/LAE1 (Loss of aflR Expression A) homologs their gene products act at the interphase between secondary metabolisms, cellulase production and development. Lack of the corresponding genes results in significant physiological changes including loss of secondary metabolite and lignocellulose degrading enzymes production. At the molecular level, the encoded proteins are presumably methyltransferases or demethylases which act directly or indirectly at heterochromatin and interact with velvet domain proteins. Velvet proteins bind to DNA and affect expression of secondary metabolites (SMs) genes and cellulases. The dynamic interplay between LaeA/LAE1, velvet proteins and additional interaction partners is the key for an understanding of the coordination of metabolic and morphological functions of fungi and is required for a biotechnological control of the formation of desired bioactive products. Aspergilli and Trichoderma represent different biotechnologically significant species with significant differences in the LaeA/LAE1-Velvet protein machinery and their target proteins. We, therefore, performed a comparative study of the interaction partners of this machinery and the dynamics of the various protein-protein interactions using our robust proteomic and mass spectrometry techniques. This enhances our knowledge about the fungal coordination of secondary metabolism, cellulase production and development and thereby will certainly improve recombinant fungal strain construction for the production of industrial secondary metabolite or lignocellulose hydrolytic enzymes.Keywords: cellulases, LaeA/1, proteomics, secondary metabolites
Procedia PDF Downloads 27012 Designing, Manufacturing and Testing a Portable Tractor Unit Biocoal Harvester Combine of Agriculture and Animal Wastes
Authors: Ali Moharrek, Hosein Mobli, Ali Jafari, Ahmad Tabataee Far
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Biomass is a material generally produced by plants living on soil or water and their derivatives. The remains of agricultural and forest products contain biomass which is changeable into fuel. Besides, you can obtain biogas and ethanol from the charcoal produced from biomass through specific actions. this technology was designed for as a useful Native Fuel and Technology in Energy disasters Management Due to the sudden interruption of the flow of heat energy One of the problems confronted by mankind in the future is the limitations of fossil energy which necessitates production of new energies such as biomass. In order to produce biomass from the remains of the plants, different methods shall be applied considering factors like cost of production, production technology, area of requirement, speed of work easy utilization, ect. In this article we are focusing on designing a biomass briquetting portable machine. The speed of installation of the machine on a tractor is estimated as 80 MF 258. Screw press is used in designing this machine. The needed power for running this machine which is estimated as 17.4 kW is provided by the power axis of tractor. The pressing speed of the machine is considered to be 375 RPM Finally the physical and mechanical properties of the product were compared with utilized material which resulted in appropriate outcomes. This machine is designed for Gathering Raw materials of the ground by Head Section. During delivering the raw materials to Briquetting section, they Crushed, Milled & Pre Heated in Transmission section. This machine is a Combine Portable Tractor unit machine and can use all type of Agriculture, Forest & Livestock Animals Resides as Raw material to make Bio fuel. The Briquetting Section was manufactured and it successfully made bio fuel of Sawdust. Also this machine made a biofuel with Ethanol of sugarcane Wastes. This Machine is using P.T.O power source for Briquetting and Hydraulic Power Source for Pre Processing of Row Materials.Keywords: biomass, briquette, screw press, sawdust, animal wastes, portable, tractors
Procedia PDF Downloads 31511 Developing a Green Information Technology Model in Australian Higher-Educational Institutions
Authors: Mahnaz Jafari, Parisa Izadpanahi, Francesco Mancini, Muhammad Qureshi
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The advancement in Information Technology (IT) has been an intrinsic element in the developments of the 21st century bringing benefits such as increased economic productivity. However, its widespread application has also been associated with inadvertent negative impacts on society and the environment necessitating selective interventions to mitigate these impacts. This study responded to this need by developing a Green IT Rating Tool (GIRT) for higher education institutions (HEI) in Australia to evaluate the sustainability of IT-related practices from an environmental, social, and economic perspective. Each dimension must be considered equally to achieve sustainability. The development of the GIRT was informed by the views of interviewed IT professionals whose opinions formed the basis of a framework listing Green IT initiatives in order of their importance as perceived by the interviewed professionals. This framework formed the base of the GIRT, which identified Green IT initiatives (such as videoconferencing as a substitute for long-distance travel) and the associated weighting of each practice. The proposed sustainable Green IT model could be integrated into existing IT systems, leading to significant reductions in carbon emissions and e-waste and improvements in energy efficiency. The development of the GIRT and the findings of this study have the potential to inspire other organizations to adopt sustainable IT practices, positively impact the environment, and be used as a reference by IT professionals and decision-makers to evaluate IT-related sustainability practices. The GIRT could also serve as a benchmark for HEIs to compare their performance with other institutions and to track their progress over time. Additionally, the study's results suggest that virtual and cloud-based technologies could reduce e-waste and energy consumption in the higher education sector. Overall, this study highlights the importance of incorporating Green IT practices into the IT systems of HEI to contribute to a more sustainable future.Keywords: green information technology, international higher-educational institution, sustainable solutions, environmentally friendly IT systems
Procedia PDF Downloads 7510 The Relationship between Functional Movement Screening Test and Prevalence of Musculoskeletal Disorders in Emergency Nurse and Emergency Medical Services Staff Shiraz, Iran, 2017
Authors: Akram Sadat Jafari Roodbandi, Alireza Choobineh, Nazanin Hosseini, Vafa Feyzi
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Introduction: Physical fitness and optimum functional movement are essential for efficiently performing job tasks without fatigue and injury. Functional Movement Screening (FMS) tests are used in screening of athletes and military forces. Nurses and emergency medical staff are obliged to perform many physical activities such as transporting patients, CPR operations, etc. due to the nature of their jobs. This study aimed to assess relationship between FMS test score and the prevalence of musculoskeletal disorders (MSDs) in emergency nurses and emergency medical services (EMS) staff. Methods: 134 male and female emergency nurses and EMS technicians participated in this cross-sectional, descriptive-analytical study. After video tutorial and practical training of how to do FMS test, the participants carried out the test while they were wearing comfortable clothes. The final score of the FMS test ranges from 0 to 21. The score of 14 is considered weak in the functional movement base on FMS test protocol. In addition to the demographic data questionnaire, the Nordic musculoskeletal questionnaire was also completed for each participant. SPSS software was used for statistical analysis with a significance level of 0.05. Results: Totally, 49.3% (n=66) of the subjects were female. The mean age and work experience of the subjects were 35.3 ± 8.7 and 11.4 ± 7.7, respectively. The highest prevalence of MSDs was observed at the knee and lower back with 32.8% (n=44) and 23.1% (n=31), respectively. 26 (19.4%) health worker had FMS test score of 14 and less. The results of the Spearman correlation test showed that the FMS test score was significantly associated with MSDs (r=-0.419, p < 0.0001). It meant that MSDs increased with the decrease of the FMS test score. Age, sex, and MSDs were the remaining significant factors in linear regression logistic model with dependent variable of FMS test score. Conclusion: FMS test seems to be a usable screening tool in pre-employment and periodic medical tests for occupations that require physical fitness and optimum functional movements.Keywords: functional movement, musculoskeletal disorders, health care worker, screening test
Procedia PDF Downloads 1299 The Relationship between Amplitude and Stability of Circadian Rhythm with Sleep Quality and Sleepiness: A Population Study, Kerman 2018
Authors: Akram Sadat Jafari Roodbandi, Farzaneh Akbari, Vafa Feyzi, Zahra Zare, Zohreh Foroozanfar
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Introduction: Circadian rhythm or sleep-awake cycle in 24 hours is one of the important factors affecting the physiological and psychological characteristics in humans that contribute to biochemical, physiological and behavioral processes and helps people to set up brain and body for sleep or active awakening during certain hours. The purpose of this study was to investigate the relationship between the characteristics of circadian rhythms on the sleep quality and sleepiness according to their demographic characteristics such as age. Methods: This cross-sectional descriptive-analytic study was carried out among the general population of Kerman, aged 15-84 years. After dividing the age groups into 10-year demographic characteristics questionnaire, the type of circadian questionnaire, Pittsburgh sleep quality questionnaire and Euporth sleepiness questionnaire were completed in equal numbers between men and women of that age group. Using cluster sampling with effect design equal 2, 1300 questionnaires were distributed during the various hours of 24 hours in public places in Kerman city. Data analysis was done using SPSS software and univariate tests and linear regressions at a significance level of 0.05. Results: In this study, 1147 subjects were included in the study, 584 (50.9%) were male and the rest were women. The mean age was 39.50 ± 15.38. 133 (11.60%) subjects from the study participants had sleepiness and 308 (26.90%) subjects had undesirable sleep quality. Using linear regression test, sleep quality was the significant correlation with sex, hours needed for sleep at 24 hours, chronic illness, sleepiness, and circadian rhythm amplitude. Sleepiness was the meaningful relationship with marital status, sleep-wake schedule of other family members and the stability of circadian rhythm. Both women and men, with age, decrease the quality of sleep and increase the rate of sleepiness. Conclusion: Age, sex, and type of circadian people, the need for sleep at 24 hours, marital status, sleep-wake schedule of other family members are significant factors related to the sleep quality and sleepiness and their adaptation to night shift work.Keywords: circadian type, sleep quality, sleepiness, age, shift work
Procedia PDF Downloads 1538 Effect of Plant Growth Promoting Rhizobacteria on the Germination and Early Growth of Onion (Allium cepa)
Authors: Dragana R. Stamenov, Simonida S. Djuric, Timea Hajnal Jafari
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Plant growth promoting rhizobacteria (PGPR) are a heterogeneous group of bacteria that can be found in the rhizosphere, at root surfaces and in association with roots, enhancing the growth of the plant either directly and/or indirectly. Increased crop productivity associated with the presence of PGPR has been observed in a broad range of plant species, such as raspberry, chickpeas, legumes, cucumber, eggplant, pea, pepper, radish, tobacco, tomato, lettuce, carrot, corn, cotton, millet, bean, cocoa, etc. However, until now there has not been much research about influences of the PGPR on the growth and yield of onion. Onion (Allium cepa L.), of the Liliaceae family, is a species of great economic importance, widely cultivated all over the world. The aim of this research was to examine the influence of plant growth promoting bacteria Pseudomonas sp. Dragana, Pseudomonas sp. Kiš, Bacillus subtillis and Azotobacter sp. on the seed germination and early growth of onion (Allium cepa). PGPR Azotobacter sp., Bacillus subtilis, Pseudomonas sp. Dragana, Pseudomonas sp. Kiš, from the collection of the Faculty of Agriculture, Novi Sad, Serbia, were used as inoculants. The number of cells in 1 ml of the inoculum was 10⁸ CFU/ml. The control variant was not inoculated. The effect of PGPR on seed germination and hypocotyls length of Allium cepa was evaluated in controlled conditions, on filter paper in the dark at 22°C, while effect on the plant length and mass in semicontrol conditions, in 10 l volume vegetative pots. Seed treated with fungicide and untreated seed were used. After seven days the percentage of germination was determined. After seven and fourteen days hypocotil length was measured. Fourteen days after germination, length and mass of plants were measured. Application of Pseudomonas sp. Dragana and Kiš and Bacillus subtillis had a negative effect on onion seed germination, while the use of Azotobacter sp. gave positive results. On average, application of all investigated inoculants had a positive effect on the measured parameters of plant growth. Azotobacter sp. had the greatest effect on the hypocotyls length, length and mass of the plant. In average, better results were achieved with untreated seeds in compare with treated. Results of this study have shown that PGPR can be used in the production of onion.Keywords: germination, length, mass, microorganisms, onion
Procedia PDF Downloads 2367 Deep Injection Wells for Flood Prevention and Groundwater Management
Authors: Mohammad R. Jafari, Francois G. Bernardeau
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With its arid climate, Qatar experiences low annual rainfall, intense storms, and high evaporation rates. However, the fast-paced rate of infrastructure development in the capital city of Doha has led to recurring instances of surface water flooding as well as rising groundwater levels. Public Work Authority (PWA/ASHGHAL) has implemented an approach to collect and discharge the flood water into a) positive gravity systems; b) Emergency Flooding Area (EFA) – Evaporation, Infiltration or Storage off-site using tankers; and c) Discharge to deep injection wells. As part of the flood prevention scheme, 21 deep injection wells have been constructed to discharge the collected surface and groundwater table in Doha city. These injection wells function as an alternative in localities that do not possess either positive gravity systems or downstream networks that can accommodate additional loads. These injection wells are 400-m deep and are constructed in a complex karstic subsurface condition with large cavities. The injection well system will discharge collected groundwater and storm surface runoff into the permeable Umm Er Radhuma Formation, which is an aquifer present throughout the Persian Gulf Region. The Umm Er Radhuma formation contains saline water that is not being used for water supply. The injection zone is separated by an impervious gypsum formation which acts as a barrier between upper and lower aquifer. State of the art drilling, grouting, and geophysical techniques have been implemented in construction of the wells to assure that the shallow aquifer would not be contaminated and impacted by injected water. Injection and pumping tests were performed to evaluate injection well functionality (injectability). The results of these tests indicated that majority of the wells can accept injection rate of 200 to 300 m3 /h (56 to 83 l/s) under gravity with average value of 250 m3 /h (70 l/s) compared to design value of 50 l/s. This paper presents design and construction process and issues associated with these injection wells, performing injection/pumping tests to determine capacity and effectiveness of the injection wells, the detailed design of collection system and conveying system into the injection wells, and the operation and maintenance process. This system is completed now and is under operation, and therefore, construction of injection wells is an effective option for flood control.Keywords: deep injection well, flood prevention scheme, geophysical tests, pumping and injection tests, wellhead assembly
Procedia PDF Downloads 1186 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
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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 775 Experimental Study Analyzing the Similarity Theory Formulations for the Effect of Aerodynamic Roughness Length on Turbulence Length Scales in the Atmospheric Surface Layer
Authors: Matthew J. Emes, Azadeh Jafari, Maziar Arjomandi
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Velocity fluctuations of shear-generated turbulence are largest in the atmospheric surface layer (ASL) of nominal 100 m depth, which can lead to dynamic effects such as galloping and flutter on small physical structures on the ground when the turbulence length scales and characteristic length of the physical structure are the same order of magnitude. Turbulence length scales are a measure of the average sizes of the energy-containing eddies that are widely estimated using two-point cross-correlation analysis to convert the temporal lag to a separation distance using Taylor’s hypothesis that the convection velocity is equal to the mean velocity at the corresponding height. Profiles of turbulence length scales in the neutrally-stratified ASL, as predicted by Monin-Obukhov similarity theory in Engineering Sciences Data Unit (ESDU) 85020 for single-point data and ESDU 86010 for two-point correlations, are largely dependent on the aerodynamic roughness length. Field measurements have shown that longitudinal turbulence length scales show significant regional variation, whereas length scales of the vertical component show consistent Obukhov scaling from site to site because of the absence of low-frequency components. Hence, the objective of this experimental study is to compare the similarity theory relationships between the turbulence length scales and aerodynamic roughness length with those calculated using the autocorrelations and cross-correlations of field measurement velocity data at two sites: the Surface Layer Turbulence and Environmental Science Test (SLTEST) facility in a desert ASL in Dugway, Utah, USA and the Commonwealth Scientific and Industrial Research Organisation (CSIRO) wind tower in a rural ASL in Jemalong, NSW, Australia. The results indicate that the longitudinal turbulence length scales increase with increasing aerodynamic roughness length, as opposed to the relationships derived by similarity theory correlations in ESDU models. However, the ratio of the turbulence length scales in the lateral and vertical directions to the longitudinal length scales is relatively independent of surface roughness, showing consistent inner-scaling between the two sites and the ESDU correlations. Further, the diurnal variation of wind velocity due to changes in atmospheric stability conditions has a significant effect on the turbulence structure of the energy-containing eddies in the lower ASL.Keywords: aerodynamic roughness length, atmospheric surface layer, similarity theory, turbulence length scales
Procedia PDF Downloads 1234 Bridging the Educational Gap: A Curriculum Framework for Mass Timber Construction Education and Comparative Analysis of Physical vs. Virtual Prototypes in Construction Management
Authors: Farnaz Jafari
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The surge in mass timber construction represents a pivotal moment in sustainable building practices, yet the lack of comprehensive education in construction management poses a challenge in harnessing this innovation effectively. This research endeavors to bridge this gap by developing a curriculum framework integrating mass timber construction into undergraduate and industry certificate programs. To optimize learning outcomes, the study explores the impact of two prototype formats -Virtual Reality (VR) simulations and physical mock-ups- on students' understanding and skill development. The curriculum framework aims to equip future construction managers with a holistic understanding of mass timber, covering its unique properties, construction methods, building codes, and sustainable advantages. The study adopts a mixed-methods approach, commencing with a systematic literature review and leveraging surveys and interviews with educators and industry professionals to identify existing educational gaps. The iterative development process involves incorporating stakeholder feedback into the curriculum. The evaluation of prototype impact employs pre- and post-tests administered to participants engaged in pilot programs. Through qualitative content analysis and quantitative statistical methods, the study seeks to compare the effectiveness of VR simulations and physical mock-ups in conveying knowledge and skills related to mass timber construction. The anticipated findings will illuminate the strengths and weaknesses of each approach, providing insights for future curriculum development. The curriculum's expected contribution to sustainable construction education lies in its emphasis on practical application, bridging the gap between theoretical knowledge and hands-on skills. The research also seeks to establish a standard for mass timber construction education, contributing to the field through a unique comparative analysis of VR simulations and physical mock-ups. The study's significance extends to the development of best practices and evidence-based recommendations for integrating technology and hands-on experiences in construction education. By addressing current educational gaps and offering a comparative analysis, this research aims to enrich the construction management education experience and pave the way for broader adoption of sustainable practices in the industry. The envisioned curriculum framework is designed for versatile integration, catering to undergraduate programs and industry training modules, thereby enhancing the educational landscape for aspiring construction professionals. Ultimately, this study underscores the importance of proactive educational strategies in preparing industry professionals for the evolving demands of the construction landscape, facilitating a seamless transition towards sustainable building practices.Keywords: curriculum framework, mass timber construction, physical vs. virtual prototypes, sustainable building practices
Procedia PDF Downloads 693 The Role of the New Silk Road (One Belt, One Road Initiative) in Connecting the Free Zones of Iran and Turkey: A Case Study of the Free Zones of Sarakhs and Maku to Anatolia and Europe
Authors: Morteza Ghourchi, Meraj Jafari, Atena Soheilazizi
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Today, with the globalization of communications and the connection of countries within the framework of the global economy, free zones play the most important role as the engine of global economic development and globalization of countries. In this regard, corridors have a fundamental role in linking countries and free zones physically with each other. One of these corridors is the New Silk Road corridor (One Belt, One Road initiative), which is being built by China to connect with European countries. In connecting this corridor to European countries, Iran and Turkey are among the countries that play an important role in linking China to European countries through this corridor. The New Silk Road corridor, by connecting Iran’s free zones (Sarakhs and Maku) and Turkey’s free zones (Anatolia and Europe), can provide the best opportunity for expanding economic cooperation and regional development between Iran and Turkey. It can also provide economic links between Iran and Turkey with Central Asian countries and especially the port of Khorgos. On the other hand, it can expand Iran-Turkey economic relations more than ever before with Europe in a vast economic network. The research method was descriptive-analytical, using library resources, documents of Iranian free zones, and the Internet. In an interview with Fars News Agency, Mohammad Reza Kalaei, CEO of Sarakhs Free Zone, said that the main goal of Sarakhs Special Economic Zone is to connect Iran with the Middle East and create a transit corridor towards East Asian countries, including Turkey. Also, according to an interview with Hussein Gharousi, CEO of Maku Free Zone, the importance of this region is due to the fact that Maku Free Zone, due to its geographical location and its position on the China-Europe trade route, the East-West corridor, which is the closest point to the European Union through railway and transit routes, and also due to its proximity to Eurasian countries, is an ideal opportunity for industrial and technological companies. Creating a transit corridor towards East Asian countries, including Turkey, is one of the goals of this project Free zones between Iran and Turkey can sign an agreement within the framework of the New Silk Road to expand joint investments and economic cooperation towards regional convergence. The purpose of this research is to develop economic links between Iranian and Turkish free zones along the New Silk Road, which will lead to the expansion and development of regional cooperation between the two countries within the framework of neighboring policies. The findings of this research include the development of economic diplomacy between the Secretariat of the Supreme Council of Free Zones of Iran and the General Directorate of Free Zones of Turkey, the agreement to expand cooperation between the free zones of Sarakhs, Maku, Anatolia, and Europe, holding biennial conferences between Iranian free zones along the New Silk Road with Turkish free zones, creating a joint investment fund between Iran and Turkey in the field of developing free zones along the Silk Road, helping to attract tourism between Iranian and Turkish free zones located along the New Silk Road, improving transit infrastructure and transportation to better connect Iranian free zones to Turkish free zones, communicating with China, and creating joint collaborations between China’s dry ports and its free zones with Iranian and Turkish free zones.Keywords: network economy, new silk road (one belt, one road initiative), free zones (Sarakhs, Maku, Anatolia, Europe), regional development, neighborhood policies
Procedia PDF Downloads 642 An Analysis of Economical Drivers and Technical Challenges for Large-Scale Biohydrogen Deployment
Authors: Rouzbeh Jafari, Joe Nava
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This study includes learnings from an engineering practice normally performed on large scale biohydrogen processes. If properly scale-up is done, biohydrogen can be a reliable pathway for biowaste valorization. Most of the studies on biohydrogen process development have used model feedstock to investigate process key performance indicators (KPIs). This study does not intend to compare different technologies with model feedstock. However, it reports economic drivers and technical challenges which help in developing a road map for expanding biohydrogen economy deployment in Canada. BBA is a consulting firm responsible for the design of hydrogen production projects. Through executing these projects, activity has been performed to identify, register and mitigate technical drawbacks of large-scale hydrogen production. Those learnings, in this study, have been applied to the biohydrogen process. Through data collected by a comprehensive literature review, a base case has been considered as a reference, and several case studies have been performed. Critical parameters of the process were identified and through common engineering practice (process design, simulation, cost estimate, and life cycle assessment) impact of these parameters on the commercialization risk matrix and class 5 cost estimations were reported. The process considered in this study is food waste and woody biomass dark fermentation. To propose a reliable road map to develop a sustainable biohydrogen production process impact of critical parameters was studied on the end-to-end process. These parameters were 1) feedstock composition, 2) feedstock pre-treatment, 3) unit operation selection, and 4) multi-product concept. A couple of emerging technologies also were assessed such as photo-fermentation, integrated dark fermentation, and using ultrasound and microwave to break-down feedstock`s complex matrix and increase overall hydrogen yield. To properly report the impact of each parameter KPIs were identified as 1) Hydrogen yield, 2) energy consumption, 3) secondary waste generated, 4) CO2 footprint, 5) Product profile, 6) $/kg-H2 and 5) environmental impact. The feedstock is the main parameter defining the economic viability of biohydrogen production. Through parametric studies, it was found that biohydrogen production favors feedstock with higher carbohydrates. The feedstock composition was varied, by increasing one critical element (such as carbohydrate) and monitoring KPIs evolution. Different cases were studied with diverse feedstock, such as energy crops, wastewater slug, and lignocellulosic waste. The base case process was applied to have reference KPIs values and modifications such as pretreatment and feedstock mix-and-match were implemented to investigate KPIs changes. The complexity of the feedstock is the main bottleneck in the successful commercial deployment of the biohydrogen process as a reliable pathway for waste valorization. Hydrogen yield, reaction kinetics, and performance of key unit operations highly impacted as feedstock composition fluctuates during the lifetime of the process or from one case to another. In this case, concept of multi-product becomes more reliable. In this concept, the process is not designed to produce only one target product such as biohydrogen but will have two or multiple products (biohydrogen and biomethane or biochemicals). This new approach is being investigated by the BBA team and the results will be shared in another scientific contribution.Keywords: biohydrogen, process scale-up, economic evaluation, commercialization uncertainties, hydrogen economy
Procedia PDF Downloads 1081 Origin of the Eocene Volcanic Rocks in Muradlu Village, Azerbaijan Province, Northwest of Iran
Authors: A. Shahriari, M. Khalatbari Jafari, M. Faridi
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Abstract The Muradlu volcanic area is located in Azerbaijan province, NW Iran. The studied area exposed in a vast region includes lesser Caucasus, Southeastern Turkey, and northwestern Iran, comprising Cenozoic volcanic and plutonic massifs. The geology of this extended region was under the influence of the Alpine-Himalayan orogeny. Cenozoic magmatic activities in this vast region evolved through the northward subduction of the Neotethyan subducted slab and subsequence collision of the Arabian and Eurasian plates. Based on stratigraphy and paleontology data, most of the volcanic activities in the Muradlu area occurred in the Eocene period. The Studied volcanic rocks overly late Cretaceous limestone with disconformity. The volcanic sequence includes thick epiclastic and hyaloclastite breccia at the base, laterally changed to pillow lava and continued by hyaloclastite and lave flows at the top of the series. The lava flows display different textures from megaporphyric-phyric to fluidal and microlithic textures. The studied samples comprise picrobasalt basalt, tephrite basanite, trachybasalt, basaltic trachyandesite, phonotephrite, tephrophonolite, trachyandesite, and trachyte in compositions. Some xenoliths with lherzolitic composition are found in picrobasalt. These xenoliths are made of olivine, cpx (diopside), and opx (enstatite), probably the remain of mantle origin. Some feldspathoid minerals such as sodalite presence in the phonotephrite confirm an alkaline trend. Two types of augite phenocrysts are found in picrobasalt, basalt and trachybasalt. The first types are shapeless, with disharmony zoning and sponge texture with reaction edges probably resulted from sodic magma, which is affected by a potassic magma. The second shows a glomerocryst shape. In discriminative diagrams, the volcanic rocks show alkaline-shoshonitic trends. They contain (0.5-7.7) k2O values and plot in the shoshonitic field. Most of the samples display transitional to potassic alkaline trends, and some samples reveal sodic alkaline trends. The transitional trend probably results from the mixing of the sodic alkaline and potassic magmas. The Rare Earth Elements (REE) patterns and spider diagrams indicate enrichment of Large-Ione Lithophile Element (LILE) and depletion of High Field Strength Elements (HFSE) relative to Heavy Rare Earth Elements (HREE). Enrichment of K, Rb, Sr, Ba, Zr, Th, and U and the enrichment of Light Rare Earth Elements (LREE) relative to Heavy Rare Earth Elements (HREE) indicate the effect of subduction-related fluids over the mantle source, which has been reported in the arc and continental collision zones. The studied samples show low Nb/La ratios. Our studied samples plot in the lithosphere and lithosphere-asthenosphere fields in the Nb/La versus La/Yb ratios diagram. These geochemical characters allow us to conclude that a lithospheric mantle source previously metasomatized by subduction components was the origin of the Muradlu volcanic rocks.Keywords: alkaline, asthenosphere, lherzolite, lithosphere, Muradlu, potassic, shoshonitic, sodic, volcanism
Procedia PDF Downloads 169