Search results for: Amir Hossein Mohammadi

Authors: Ghorbanali Mohammadi

Abstract:

Background: Due to the widespread outbreak of the COVID-19 virus, a large number of people become infected with the disease every day and go to hospitals. The acute condition of this disease has caused the death of many people. Since all the stages of treatment for these people happen in the hospitals, nurses are at the forefront of the fight against this virus. This causes nurses to suffer from physical and mental health problems. Methods: Physical and mental problems in nurses were assessed using the Depression, Anxiety and Stress Scale (DASS-42) of Lovibond (1995) and the Nordic Questionnaire. Results: 90 nurses from emergency, intensive care, and coronary care units were examined, and a total of 180 questionnaires were collected and evaluated. It was found that 37.78%, 47.78%, and 21.11% of nurses have symptoms of depression, anxiety, and stress, respectively. 40% of the nurses had physical problems. In total, 65.17% of them were involved in one or more mental or physical illnesses. Conclusions: Of the three units surveyed, the nurses in intensive care, emergency room, and coronary care units worked more than ten hours a day. Examining the interaction of physical and mental health problems indicated that physical problems can aggravate mental problems.

Keywords: depression anxiety and stress scale of Lovibond, nordic questionnaire, mental health of nurses, physical health problems in nurses

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Authors: Sumaiya Amir Khan, Shayma Al-Sharif, Samiha Mazher, Neha Intikhab Khan

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This research paper aims to evaluate the effectiveness of sleep-tracking AI applications in smart-watches. It focuses on comparing the sleep analyses of two different smartwatch brands, Samsung and Fitbit, and measuring sleep at three different stages – REM (Rapid-Eye-Movement), NREM (Non-Rapid-Eye-Movement), and deep sleep. The methodology involves the participation of different users and analyzing their sleep data. The results reveal that although light sleep is the longest stage, deep sleep is higher than average in the participants. The study also suggests that light sleep is not uniform, and getting higher levels of deep sleep can prevent debilitating health conditions. Based on the findings, it is recommended that individuals should aim to achieve higher levels of deep sleep to maintain good health. Overall, this research contributes to the growing literature on the effectiveness of sleep-tracking AI applications and their potential to improve sleep quality.

Keywords: sleep tracking, lifestyle, accuracy, health, AI, AI features, ML

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Authors: Abdolreza Esmaeilzadeh, Maryam Erfanmanesh, Sousan Ghasemi, Farzaneh Mohammadi

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Background: Hepatitis C Virus (HCV), a public health problem, is an enveloped, single-stranded RNA virus and a member of the Hepacivirus genus of the Flaviviridae family. Liver cancer, cirrhosis, and end-stage liver are the outcomes of chronic infection with HCV. HCV isolates show significant heterogeneity in genetics around the world. Therefore, determining HCV genotypes is a vital step in determining prognosis and planning therapeutic strategies. Materials and Methods: Serum samples of 136 patients were collected and analyzed for anti-HCV antibodies using ELISA (The enzyme-linked immunosorbent assay) method. Then, positive samples were exposed to RT-PCR, which was performed under standard condition. Afterwards, they investigated for genotyping using allele-specific PCR (AS-PCR), and HCV genotype 2.0 line probe assay (LiPA). Results: Samples indicated 216 bp bands on 2% agarose gel. Analyses of the results demonstrated that the most dominant subtype was 3a with frequency of 38.26% in Zanjan Province followed by subtypes of 1b, 1a, 2, and 4 with frequencies of 25.73%, 22.05%, 5.14%, and 4.41%, respectively. The frequency of unknown HCV genotypes was 4.41%. Conclusions: According to the results, it was found that HCV high prevalent genotype in Zanjan is subtype 3a. Analysis of the results provides identification of certain HCV genotypes, and these valuable findings could affect the type and duration of the treatment.

Keywords: anti-HCV antibody, Hepatitis C Virus (HCV), genotype, RT-PCR, AS-PCR

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Authors: Karim Hamidi Machekposhti, Hossein Sedghi

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This study was designed to find the best-fit probability distribution of annual rainfall based on 50 years sample (1966-2015) in the Karkheh river basin at Iran using six probability distributions: Normal, 2-Parameter Log Normal, 3-Parameter Log Normal, Pearson Type 3, Log Pearson Type 3 and Gumbel distribution. The best fit probability distribution was selected using Stormwater Management and Design Aid (SMADA) software and based on the Residual Sum of Squares (R.S.S) between observed and estimated values Based on the R.S.S values of fit tests, the Log Pearson Type 3 and then Pearson Type 3 distributions were found to be the best-fit probability distribution at the Jelogir Majin and Pole Zal rainfall gauging station. The annual values of expected rainfall were calculated using the best fit probability distributions and can be used by hydrologists and design engineers in future research at studied region and other region in the world.

Keywords: Log Pearson Type 3, SMADA, rainfall, Karkheh River

Procedia PDF Downloads 179

Authors: Seyed Abolhasan Naeini, Mohammad Hossein Zade

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This article is an attempt to present a numerically study of the behaviour of an eccentrically loaded circular footing resting on sand to determine ‎its ultimate bearing capacity. A surface circular footing of diameter 12 cm (D) was used as ‎shallow foundation. For this purpose, three dimensional models consist of foundation, and medium sandy soil was modelled by ABAQUS software. Bearing capacity of footing was evaluated and the ‎effects of the load eccentricity on bearing capacity, its settlement, and modulus of subgrade reaction were studied. Three different values of load eccentricity with equal space from inside the core on the core boundary and outside the core boundary, which were respectively e=0.75, 1.5, and 2.25 cm, were considered. The results show that by increasing the load eccentricity, the ultimate load and the ‎modulus of subgrade reaction decreased.

Keywords: circular foundation, sand, eccentric loading, modulus of subgrade reaction

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Authors: Leila Samiee, Amir Yadegari, Saeedeh Tasharrofi

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In the work presented here, nitrogen-doped graphene materials were synthesized and used as metal-free electrocatalysts for oxygen reduction reaction (ORR) under alkaline conditions. Paraphenylenediamine was used as N precursor. The N-doped graphene was synthesized under hydrothermal treatment at 200°C. All the materials have been characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM) and X-ray photo-electron spectroscopy (XPS). Moreover, for electrochemical evaluation of samples, Rotating Disk electrode (RDE) and Cyclic Voltammetry techniques (CV) were employed. The resulting material exhibits an outstanding catalytic activity for the oxygen reduction reaction (ORR) as well as excellent resistance towards methanol crossover effects, indicating their promising potential as ORR electrocatalysts for alkaline fuel cells.

Keywords: alkaline fuel cell, graphene, metal-free catalyst, paraphenylen diamine

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Authors: Iman Mazinani, Zubaidah Ismail, Ahmad Mustafa Hashim, Amir Reza Saba

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Two tragic tsunamis that devastated the west coast of Sumatra Island, Indonesia in 2004 and North East Japan in 2011 had damaged bridges to various extents. Tsunamis have resulted in the catastrophic deterioration of infrastructures i.e. coastal structures, utilities and transportation facilities. A bridge structure performs vital roles to enable people to perform activities related to their daily needs and for development. A damaged bridge needs to be repaired expeditiously. In order to understand the effects of tsunami forces on bridges, experimental tests are carried out to measure the characteristics of hydrodynamic force at various wave heights. Coastal bridge models designed at a 1:40 scale are used in a 24.0 m long hydraulic flume with a cross section of 1.5 m by 2.0 m. The horizontal forces and uplift forces in all cases show that forces increase nonlinearly with increasing wave amplitude.

Keywords: tsunami, bridge, horizontal force, uplift force

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Authors: Amirreza Kosari, Hossein Maghsoudi, Malahat Givar

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In this study, the three-dimensional optimal path planning of a flying robot for Terrain Following / Terrain Avoidance (TF/TA) purposes using Direct Collocation has been investigated. To this purpose, firstly, the appropriate equations of motion representing the flying robot translational movement have been described. The three-dimensional optimal path planning of the flying vehicle in terrain following/terrain avoidance maneuver is formulated as an optimal control problem. The terrain profile, as the main allowable height constraint has been modeled using Fractal Generation Method. The resulting optimal control problem is discretized by applying Direct Collocation numerical technique, and then transformed into a Nonlinear Programming Problem (NLP). The efficacy of the proposed method is demonstrated by extensive simulations, and in particular, it is verified that this approach could produce a solution satisfying almost all performance and environmental constraints encountering a low-level flying maneuver

Keywords: path planning, terrain following, optimal control, nonlinear programming

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Authors: Seyed Hassan Moosa-kazemi, Jalal Mohammadi Soleimani, Hassan Vatandoost, Mohammad Hassan Shirazi, Sara Hajikhani, Roonak Bakhtiari, Morteza Akbari, Siamak Hydarzadeh

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Malaria is an infectious disease and considered most important health problems in the southeast of Iran. Iran is elimination malaria phase and new tool need to vector control. Paraterasgenesis is a new way to cut of life cycle of the malaria parasite. In this study, the microflora of the surface and gut of various stages of Anopheles fluviatilis James as one of the important malaria vector was studied using biochemical and molecular techniques during 2013-2014. Twelve bacteria species were found including; Providencia rettgeri, Morganella morganii, Enterobacter aerogenes, Pseudomonas oryzihabitans, Citrobacter braakii، Citrobacter freundii، Aeromonas hydrophila، Klebsiella oxytoca, Citrobacter koseri, Serratia fonticola، Enterobacter sakazakii and Yersinia pseudotuberculosis. The species of Alcaligenes faecalis, Providencia vermicola and Enterobacter hormaechei were identified in various stages of the vector and confirmed by biochemical and molecular techniques. We found Providencia rettgeri proper candidate for paratransgenesis.

Keywords: Anopheles fluviatilis, bacteria, malaria, Paraterasgenesis, Southern Iran

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Authors: Amir Mabhout, Toktam Ghafarian, Amirhossein Farzin, Zahra Makki, Sajjad Alizadeh, Amirhossein Ghavi

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The high number of Netflix subscribers makes it attractive for data scientists to extract valuable knowledge from the viewers' behavioural analyses. This paper presents a set of statistical insights into viewers' viewing history. After that, a deep learning model is used to predict the future watching behaviour of the users based on previous watching history within the Netflixlatte data pool. Netflixlatte in an aggregated and anonymized data pool of 320 Netflix viewers with a length 250 000 data points recorded between 2008-2022. We observe insightful correlations between the distribution of viewing time and the COVID-19 pandemic outbreak. The presented deep learning model predicts future movie and TV series viewing habits with an average loss of 0.175.

Keywords: data analysis, deep learning, LSTM neural network, netflix

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Authors: Abdul Amir Hazbavi

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In recent years, there have been increasing requests in the field of translation studies to develop software facilitating the analysis of corpora. One of the specialized tools in that regard are Terminology Management Tools. Briefly explaining, Terminology Management Tools are applications developed to help create and store terminological data in the form which allows for a controlled use of the data. While it has a long history and an established ground in translation market in most parts of the globe, the Iranian translators and translation market still seem to be unaware or unfamiliar with Terminology Management Tools. In order to provide a preview on the perception and adoption of Terminology Management Tools by the Iranian translators, the present survey was carried out among 224 last-year undergraduate Iranian students of English translation at 10 different universities across the country. The study revealed a very low level of adoption and a very high level of willingness to get familiar with and learn about Terminology Management Tools by the Iranian translators.

Keywords: translation, translation technology, terminology management tools, terminology management survey

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Authors: Amir Hamzeh Haghiabi

Abstract:

Water resource management is of global significance as it plays a key role in the socioeconomic development of all nations. On account of the fact that Iran is situated in a highly pressurized belt in the world, precipitation is limited, so that the average annual precipitation in the country is about 250 mm, only about one third to one quarter of the world average for rainfall. Karkheh basin is located in the semiarid and arid regions of Western Iran, an area with severe water scarcity. 70 % of rainfall is directly evaporated. The potential annual evaporation of the southern and northern regions is 3,600 mm 1,800 mm, respectively. In this paper, Some aspects of water resources management for this region, the specifications of the Karkheh reservoir dam & hydroelectric power plant as the biggest dam in history of Iran with total volume of reservoir 7.3 Bm3 are illustrated. Also the situation of water availability in the basin, surface and groundwater potential are considered.

Keywords: Iran, water availability, water resources, Zagros

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Authors: Shahin Mirshekari, Mohammadreza Moradi, Hossein Jafari, Mehdi Jafari, Mohammad Ensaf

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This research employs Gaussian Process Regression (GPR) with an ensemble kernel, integrating Exponential Squared, Revised Matern, and Rational Quadratic kernels to analyze pharmaceutical sales data. Bayesian optimization was used to identify optimal kernel weights: 0.76 for Exponential Squared, 0.21 for Revised Matern, and 0.13 for Rational Quadratic. The ensemble kernel demonstrated superior performance in predictive accuracy, achieving an R² score near 1.0, and significantly lower values in MSE, MAE, and RMSE. These findings highlight the efficacy of ensemble kernels in GPR for predictive analytics in complex pharmaceutical sales datasets.

Keywords: Gaussian process regression, ensemble kernels, bayesian optimization, pharmaceutical sales analysis, time series forecasting, data analysis

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Authors: Elham Fakhrpoor, Daryush Mohammadi Zanjirani, Maziyar Nojaba

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Business process reengineering is one of the most important strategies in banks in recent years that not only it increases customers’ satisfaction, but also it increases performance of banks. The purpose of elementary (initial) business process reengineering is reinforcing banks abilities to obtain new customers and making long-term relationships with existed customers and increasing customers’ satisfaction among service quality in global level. Banks specially the private ones are the main streams of state, because cash flow is necessary to survive a state. What guarantees survival and permanency of financial institutes’ activities is providing favorite, certain, and proper services. Capital market being small and state financial system being bank-oriented needs optimum usage from banks. According to this fact and role and importance of developing banking system, the present study tried to offer a constructed model using Lisrel and also spss software to evaluate effects of business process reengineering on performance of private banks. We have one min hypothesis and four sub-hypotheses. The main hypothesis says reengineering factors have positive effects on bank performances (balanced- scores card aspects). These hypotheses were tested by structural equations modeling.

Keywords: effect, business, reengineering, private bank

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Authors: Shef Amir Arasy

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In 2023, the world's population will be 7.8 billion, which has increased significantly in the last 20 years. Every country in the world is experiencing the impacts of climate change directly and indirectly. However, the community still needs to build massive infrastructure and buildings. The massive CO2 emissions which lead to climate change come from cement usage in construction activity. Bamboo is one of the most sustainable materials for reducing carbon emissions and releasing more than 30% oxygen compared to the mass of trees. Besides, bamboo harvest time is faster than other sustainable materials, around 3-4 years. Furthermore, Bamboo has a high tensile strength, which can provide ductility effectively to prevent damage to buildings during an earthquake. By the finite element method, this research analyzes bamboo configuration and connection for tall building structures under different earthquake frequencies and fire. The aim of this research is to provide proper design and connection of bamboo buildings that can be more reliable than concrete structures.

Keywords: bamboo, concrete, ductility, earthquake.

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Authors: Samaneh Rahimirshnani, Hossein Jafari

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In this paper, we consider fluid queueing processes fed by an isonormal Gaussian process. We study the correlation structure of the queueing process and the rate of convergence of the running supremum in the queueing process. The Malliavin calculus techniques are applied to obtain relations that show the workload process inherits the dependence properties of the input process. As examples, we consider two isonormal Gaussian processes, the sub-fractional Brownian motion (SFBM) and the fractional Brownian motion (FBM). For these examples, we obtain upper bounds for the covariance function of the queueing process and its rate of convergence to zero. We also discover that the rate of convergence of the queueing process is related to the structure of the covariance function of the input process.

Keywords: queue length process, Malliavin calculus, covariance function, fractional Brownian motion, sub-fractional Brownian motion

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Authors: Arianne Van Der Wal, Femke Van Horen, Amir Grinstein

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Consumers in today’s world are confronted with the alarming consequences of unsustainable behavior such as pollution and resource degradation. In addition, they are facing an increase in uncertainty due to, for instance, economic instability and terror attacks. Although these two problems are central to consumers’ lives, occur on a global scale, and have significant impact on the world’s political, economic, environmental, and social landscapes, they have not been systematically studied in tandem before. Contributing to research on persuasion and pro-social behavior, this paper shows in five studies (three experimental studies and one field study) that the two problems are intertwined. We demonstrate that uncertainty leads to lower sustainable behavior in comparison to certainty (Studies 1 and 2) and that this is due to consumers displaying higher levels of temporal discounting (i.e., adopting a more immediate orientation; Study 2). Finally, providing valuable implications for policy makers and responsible marketers, we show that emphasizing the immediate benefits of sustainable behavior during uncertainty buffers the negative effect (Studies 3 and 4).

Keywords: sustainable behavior, uncertainty, temporal discounting, framing

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Authors: Mostafa Dastori, Sirus Mohammadi

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While plug-in electric vehicles (PEVs) potentially have the capability to fulfill the energy storage needs of the electric grid, the degradation on the battery during this operation makes it less preferable by the auto manufacturers and consumers. On the other hand, the on-board chargers can also supply energy storage system applications such as reactive power compensation, voltage regulation, and power factor correction without the need of engaging the battery with the grid and thereby preserving its lifetime. It presents the design motives of single-phase on-board chargers in detail and makes a classification of the chargers based on their future vehicle-to-grid usage. The pros and cons of each different ac–dc topology are discussed to shed light on their suit- ability for reactive power support. This paper also presents and analyzes the differences between charging-only operation and capacitive reactive power operation that results in increased demand from the dc-link capacitor (more charge/discharge cycles and in- creased second harmonic ripple current). Moreover, battery state of charge is spared from losses during reactive power operation, but converter output power must be limited below its rated power rating to have the same stress on the dc-link capacitor.

Keywords: energy storage system, battery unit, cost, optimal sizing, plug-in electric vehicles (PEVs), smart grid

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Authors: Majid Mokhtari, Masoud Bahrami Alamdarlo, Babak Nazari, Hossein Zakerinya, Mehdi Salehi

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In this study, microstructure, macro, and microhardness of phases for three grades of cast iron rolls with modified chemical composition using a light microscope (OM) and electron microscopy (SEM) were investigated. The grades were chosen from Chodan Sazan Manufacturing Co. (CSROLL) productions for finishing stands of hot strip mills. The percentage of residual austenite was determined with a ferrite scope magnetic device. Thermal susceptibility testing was also measured. The results show the best oxidation resistance at high temperatures is graphitic high chromium white cast iron alloy. In order to evaluate the final properties of these grades in rolling lines, the results of the Pin on Disk abrasion test showed the superiority of the abrasive behavior of the white chromium graphite cast iron alloy grade sample at the same hardness compared to conventional alloy grades and the enhanced grades.

Keywords: hot roller, wear, behavior, microstructure

Procedia PDF Downloads 216

Authors: Seyed Mehrzad Pahlavani, Mozaffar Haji Jafari Anaraki, Sayma Mohammadi

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A total of 34700 day-old broilers were exposed to green, blue and yellow light using a light-emitting diode system for 6 weeks to investigate the effects of light wave length on antibody responses to Newcastle disease by HI test and the correlation with ELISA. 3 poultry house broiler farms with the same conditions was selected and the lightening system of each was set according to the requirement. Blood samples were taken from 20 chicks on days 1, 24 and 46 and the Newcastle virus specific antibody was titered in serum using HI an ELISA test. On day 24, the probability value of more than 0/05 was observed in HI and ELISA tests of all groups while at the end of breeding period, the average HI serum antibody titer was more in the green light than the yellow one while the blue light was not significantly different from both. At the last titration, the green light has got the highest titer of Newcastle antibodies. There were no significant differences of Newcastle antibody titers between all groups and ages in broiler pullets in ELISA. According to the sampling and analysis of HI and ELISA serum tests, there were no significant relationships between all broiler pullets breeding in green, blue and yellow light on days 24 and 46 and the P-value was more than 0/05. It is suggested that the monochromatic light is effective on broilers immunity against Newcastle disease.

Keywords: monochromatic light, Newcastle disease, HI test, ELISA test

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Authors: Soltani Amir, Wang Xuan

Abstract:

The advantage of using non-linear passive damping system in vibration control of two adjacent structures is investigated under their base excitation. The base excitation is El Centro earthquake record acceleration. The damping system is considered as an optimum and effective non-linear viscous damper that is connected between two adjacent structures. A Matlab program is developed to produce the stiffness and damping matrices and to determine a time history analysis of the dynamic motion of the system. One structure is assumed to be flexible while the other has a rule as laterally supporting structure with rigid frames. The response of the structure has been calculated and the non-linear damping coefficient is determined using optimum LQR algorithm in an optimum vibration control system. The non-linear parameter of damping system is estimated and it has shown a significant advantage of application of this system device for vibration control of two adjacent tall building.

Keywords: active control, passive control, viscous dampers, structural control, vibration control, tall building

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Authors: S. Hehni Meidani Behzad, Mokhtari Karchegani Amir, Mabodi Samad

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There are some TLE (Transfer Line Exchanger) that their lifetime reduced to 4 years instead of 30 years and after 4 years, we saw corroded area on one part of those T.L.E. that named Oval header and this happened in condition that other parts of those TLE were safe and perfect. By using of thickness measurement devices, we find that thickness reduces unusually on that part and after research and doing computer analysis with fluent software, it was recognized that on that part, we have high temperature and when this out of range temperature adds to bad quality of water, corrosion increased with high rate on that part and after more research it became obviously that it case by more excess air in furnace that located before this T.L.E. that this more air case to consuming more fuel to reach same furnace temperature so it concluded that inner coil fluid temperature increased and after received to T.L.E, this case happened and deflector condition, creep in coil and material analysis confirmed that condition.

Keywords: Transfer Line Exchanger (TLE), CFD, corrosion, erosion, tube, oval header

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Authors: Amir Alirezaei, Shahram Vahdani

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This study estimates the seismic demands of tall buildings with central symmetric setbacks by using nonlinear time history analysis. Three setback structures, all 60-story high with setback in three levels, are used for evaluation. The effects of irregularities occurred by setback, are evaluated by determination of global-drift, story-displacement and story drift. Story-displacement is modified by roof displacement and first story displacement and story drift is modified by global drift. All results are calculated at the center of mass and in x and y direction. Also the absolute values of these quantities are determined. The results show that increasing of vertical irregularities increases the global drift of the structure and enlarges the deformations in the height of the structure. It is also observed that the effects of geometry irregularity in the seismic deformations of setback structures are higher than those of mass irregularity.

Keywords: deformation demand, drift, setback, tall building

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Authors: Simin Asadollahi, Amir H. Soruri, Ali Moghimi

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Nowadays, salad oils are used in many countries around the world. Therefore, it is of great importance to ensure the safety of these food products which are usually packaged in Polyethylene terephthalate (PET) bottles and come on the market. This study investigated the effects of storage time and temperature on the migration rate of phthalate compounds from PET bottle to salad oil. In more detail, migration rate of bis (2-ethylhexyl) phthalate from bottles to salad oil samples was measured in 1st, the 30th, and the 60th days of storage at a temperature of either 20 or 40 °C. At both storage temperatures, an increase in the storage time led to a statistically significant increase in the migration rate of phthalate compounds (p<.01). Regarding this, the highest migration rate occurred after 60 days of storage in to the samples. Furthermore, it was revealed bis (2-ethylhexyl) phthalate had a higher migration rate at 40 °C than at 20 °C which showed that an increase in the storage temperature would lead to an increase in the migration rate. The highest migration rate occurred in relation to salad oil stored at 40 °C and after 60 days of storage.

Keywords: salad oil, migration rate, polyethylene terephthalate, bis (2-ethylhexyl) phthalate

Procedia PDF Downloads 339

Authors: Soltani Amir, Hu Jiaxin

Abstract:

Determination of optimal parameters of a passive control system device is the primary objective of this study. Expanding upon the use of control devices in wind and earthquake hazard reduction has led to development of various control systems. The advantage of non-linearity characteristics in a passive control device and the optimal control method using LQR algorithm are explained in this study. Finally, this paper introduces a simple approach to determine optimum parameters of a nonlinear viscous damper for vibration control of structures. A MATLAB program is used to produce the dynamic motion of the structure considering the stiffness matrix of the SDOF frame and the non-linear damping effect. This study concluded that the proposed system (variable damping system) has better performance in system response control than a linear damping system. Also, according to the energy dissipation graph, the total energy loss is greater in non-linear damping system than other systems.

Keywords: passive control system, damping devices, viscous dampers, control algorithm

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Authors: Amir Masoud Dabagh, Mahsa Khaleghi

Abstract:

The world has entered a new phase of cultural, social, economic, and so on in the last two centuries. Apart from its positive benefits and achievements to the world, it has also incurred many costs, most of which can be mentioned as destroying or at least diminishing the role of the costumes, traditions and authentic culture of the past communities. Understanding what lasts in traditional arts is vital and worthy of study because receiving it and embracing art and forms of art using that last the artistic creation removes the age-old color and smell of its face, making it immortal and persistent in all ages. This paper attempts to present traditional art concepts and solutions for interior design with the approach of handicrafts recreation as a symbol and manifestation of national identity and proof of ancient civilizations, which is at the center of tourists' attention today. The research method is a descriptive-analytical one that first explores the theoretical foundations of research, which are the concepts of recreation and traditional arts, and analyzes the process of recreation that conceals the recollection of past experiences as well as the dynamics and creativity.

Keywords: recreation, handicrafts, interior design, concept, traditional arts

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Authors: Amir Lotfi, Seyed Hamid Hosseini

Abstract:

During the recent past, due to the increase of electrical energy demand and governmental resources constraints in creating additional capacity in the generation, transmission, and distribution, privatization, and restructuring in electrical industry have been considered. So, in most of the countries, different parts of electrical industry like generation, transmission, and distribution have been separated in order to create competition. Considering these changes, environmental issues, energy growth, investment of private equity in energy generation units and difficulties of transmission lines expansion, distributed generation (DG) units have been used in power systems. Moreover, reduction in the need for transmission and distribution, the increase of reliability, improvement of power quality, and reduction of power loss have caused DG to be placed in power systems. On the other hand, considering low liquidity need, private investors tend to spend their money for DGs. In this project, the main goal is to offer an algorithm for planning and placing DGs in order to reduce the need for transmission and distribution network.

Keywords: planning, transmission, distributed generation, power security, power systems

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Authors: Mohammadhadi Mirmohammadi, Reza Safian, Hossein Haddad

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This paper presents an innovative solution for complex multi-objective optimization problem which is a part of efforts toward maximizing rolling mill throughput and minimizing processing costs in tandem cold rolling. This computational intelligence based optimization has been applied to the rolling schedules of tandem cold rolling mill. This method involves the combination of two derivative-free optimization procedures in the form of nested loops. The first optimization loop is based on Improving Hit and Run method which focus on balance of power, force and reduction distribution in rolling schedules. The second loop is a real-coded genetic algorithm based optimization procedure which optimizes energy consumption and productivity. An experimental result of application to five stand tandem cold rolling mill is presented.

Keywords: derivative-free optimization, Improving Hit and Run method, real-coded genetic algorithm, rolling schedules of tandem cold rolling mill

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Authors: Khaled Abou-El-Hossein

Abstract:

The presentation will address the features of two IR convex lenses that have been manufactured using an ultra-high precision machining centre based on single-point diamond turning. The lenses are made from silicon and germanium with a radius of curvature of 500 mm. Because of the brittle nature of silicon and germanium, machining parameters were selected in such a way that ductile regime was achieved. The cutting speed was 800 rpm while the feed rate and depth cut were 20 mm/min and 20 um, respectively. Although both materials comprise a mono-crystalline microstructure and are quite similar in terms of optical properties, machining of silicon was accompanied with more difficulties in terms of form accuracy compared to germanium machining. The P-V error of the silicon profile was 0.222 um while it was only 0.055 um for the germanium lens. This could be attributed to the accelerated wear that takes place on the tool edge when turning mono-crystalline silicon. Currently, we are using other ranges of the machining parameters in order to determine their optimal range that could yield satisfactory performance in terms of form accuracy when fabricating silicon lenses.

Keywords: diamond turning, optical surfaces, precision machining, surface roughness

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Authors: Amir Doustgani

Abstract:

Melt electrospinning is a safe and simple technique for the production of micro and nanofibers which can be an alternative to conventional solvent electrospinning. The effects of various melt-electrospinning parameters, including molecular weight, electric field strength, flow rate and temperature on the morphology and fiber diameter of polylactic acid were studied. It was shown that molecular weight was the predominant factor in determining the obtainable fiber diameter of the collected fibers. An orthogonal design was used to examine process parameters. Results showed that molecular weight is the most effective parameter on the average fiber diameter of melt electrospun PLA nanofibers and the flow rate has the less important impact. Mean fiber diameter increased by increasing MW and flow rate, but decreased by increasing electric field strength and temperature. MFD of optimized fibers was below 100 nm and the result of software was in good agreement with the experimental condition.

Keywords: fiber formation, processing, spinning, melt blowing

Procedia PDF Downloads 422