Search results for: Mohammad Mehrabioun Mohammadi
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1467

Search results for: Mohammad Mehrabioun Mohammadi

1287 A Field Study of Monochromatic Light Effects on Antibody Responses to Newcastle Disease by HI Test and the Correlation with ELISA

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

Abstract:

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

Procedia PDF Downloads 630
1286 Comparison of Intraocular Pressure Measurement Prior and Following Full Intracorneal Ring Implantation in Patient with Keratoconus by Three Different Instruments

Authors: Seyed Aliasghar Mosavi, Mostafa Naderi, Khosrow Jadidi, Amir Hashem Mohammadi

Abstract:

To study the measurement of intraocular pressure (IOP) before and after implantation of intrastromal corneal ring (MyoRing) in patients with keratoconus. Setting: Baqiyatallah University of Medical Sciences, Tehran, Iran. Methods: We compared the IOP of 13 eyes which underwent MyoRing implantation prior and six months post operation using Goldman applanation (as gold standard), Icare, and Corvis ST (uncorrected, corrected and corrected with cornea biomechanics). Results: The resulting intraocular pressure measurements prior to surgery, Icare, Corvis (corrected with cornea biomechanics) overestimated the IOP, however measurements by Corvis uncorrected underestimate the IOP. The resulting intraocular pressure measurements after surgery, Icare, Corvis (corrected with cornea biomechanics) overestimated the IOP but measurements by Corvis uncorrected underestimate the IOP. Conclusion: Consistent intraocular pressure measurements on eyes with Myoring in keratoconus can be obtained with the Goldman applanation tonometer as the gold standard measurement. We were not able to obtain consistent results when we measured the IOP by Icare and Corvis prior and after surgery.

Keywords: intraocular pressure, MyoRing, Keratoconus, Goldmann applanation, Icare, Corvis ST

Procedia PDF Downloads 215
1285 Bioinformatics Identification of Rare Codon Clusters in Proteins Structure of HBV

Authors: Abdorrasoul Malekpour, Mohammad Ghorbani Mojtaba Mortazavi, Mohammadreza Fattahi, Mohammad Hassan Meshkibaf, Ali Fakhrzad, Saeid Salehi, Saeideh Zahedi, Amir Ahmadimoghaddam, Parviz Farzadnia Dr., Mohammadreza Hajyani Asl Bs

Abstract:

Hepatitis B as an infectious disease has eight main genotypes (A–H). The aim of this study is to Bioinformatically identify Rare Codon Clusters (RCC) in proteins structure of HBV. For detection of protein family accession numbers (Pfam) of HBV proteins; used of uni-prot database and Pfam search tool were used. Obtained Pfam IDs were analyzed in Sherlocc program and RCCs in HBV proteins were detected. In further, the structures of TrEMBL entries proteins studied in PDB database and 3D structures of the HBV proteins and locations of RCCs were visualized and studied using Swiss PDB Viewer software. Pfam search tool have found nine significant hits and 0 insignificant hits in 3 frames. Results of Pfams studied in the Sherlocc program show this program not identified RCCs in the external core antigen (PF08290) and truncated HBeAg protein (PF08290). By contrast the RCCs become identified in Hepatitis core antigen (PF00906) Large envelope protein S (PF00695), X protein (PF00739), DNA polymerase (viral) N-terminal domain (PF00242) and Protein P (Pf00336). In HBV genome, seven RCC identified that found in hepatitis core antigen, large envelope protein S and DNA polymerase proteins and proteins structures of TrEMBL entries sequences that reported in Sherlocc program outputs are not complete. Based on situation of RCC in structure of HBV proteins, it suggested those RCCs are important in HBV life cycle. We hoped that this study provide a new and deep perspective in protein research and drug design for treatment of HBV.

Keywords: rare codon clusters, hepatitis B virus, bioinformatic study, infectious disease

Procedia PDF Downloads 446
1284 Investigating the Relationship between Place Attachment and Sustainable Development of Urban Spaces

Authors: Hamid Reza Zeraatpisheh, Ali Akbar Heidari, Soleiman Mohammadi Doust

Abstract:

This study has examined the relationship between place attachment and sustainable development of urban spaces. To perform this, the components of place identity, emotional attachment, place attachment and social bonding which totally constitute the output of place attachment, by means of the standardized questionnaire measure place attachment in three domains of (cognitive) the place identity, (affective) emotional attachment and (behavioral) place attachment and social bonding. To measure sustainable development, three components of sustainable development, including society, economy and environment has been considered. The study is descriptive. The assessment instrument is the standard questionnaire of Safarnia which has been used to measure the variable of place attachment and to measure the variable of sustainable development, a questionnaire has been made by the researcher and been based on the combined theoretical framework. The statistical population of this research has been the city of Shiraz. The statistical sample has been Hafeziyeh. SPSS software has been used to analyze the data and examined the results of both descriptive and inferential statistics. In inferential statistics, Pearson correlation coefficient has been used to examine the hypotheses. In this study, the variable of place attachment is high and sustainable development is also in a high level. These results suggest a positive relationship between attachment to place and sustainable development.

Keywords: place attachment, sustainable development, economy-society-environment, Hafez's tomb

Procedia PDF Downloads 667
1283 A New Optimization Algorithm for Operation of a Microgrid

Authors: Sirus Mohammadi, Rohala Moghimi

Abstract:

The main advantages of microgrids are high energy efficiency through the application of Combined Heat and Power (CHP), high quality and reliability of the delivered electric energy and environmental and economic advantages. This study presents an energy management system (EMS) to optimize the operation of the microgrid (MG). In this paper an Adaptive Modified Firefly Algorithm (AMFA) is presented for optimal operation of a typical MG with renewable energy sources (RESs) accompanied by a back-up Micro-Turbine/Fuel Cell/Battery hybrid power source to level the power mismatch or to store the energy surplus when it’s needed. The problem is formulated as a nonlinear constraint problem to minimize the total operating cost. The management of Energy storage system (ESS), economic load dispatch and operation optimization of distributed generation (DG) are simplified into a single-object optimization problem in the EMS. The proposed algorithm is tested on a typical grid-connected MG including WT/PV/Micro Turbine/Fuel Cell and Energy Storage Devices (ESDs) then its superior performance is compared with those from other evolutionary algorithms such as Genetic Algorithm (GA), Particle Swarm Optimization (PSO), Fuzzy Self Adaptive PSO (FSAPSO), Chaotic Particle PSO (CPSO), Adaptive Modified PSO (AMPSO), and Firefly Algorithm (FA).

Keywords: microgrid, operation management, optimization, firefly algorithm (AMFA)

Procedia PDF Downloads 313
1282 Between AACR2 and RDA What Changes Occurs in Them

Authors: Ibrahim Abdullahi Mohammad

Abstract:

A library catalogue exists not only as an inventory of the collections of the particular library, but also as a retrieval device. It is provided to assist the library user in finding whatever information or information resources they may be looking for. The paper proposes that this location objective of the library catalogue can only be fulfilled, if the library catalogue is constructed, bearing in mind the information needs and searching behavior of the library user. Comparing AACR2 and RDA viz-a-viz the changes RDA has introduced into bibliographic standards, the paper tries to establish the level of viability of RDA in relation to AACR2.

Keywords: library catalogue, information retrieval, AACR2, RDA

Procedia PDF Downloads 21
1281 Finite Volume Method in Loop Network in Hydraulic Transient

Authors: Hossain Samani, Mohammad Ehteram

Abstract:

In this paper, we consider finite volume method (FVM) in water hammer. We will simulate these techniques on a looped network with complex boundary conditions. After comparing methods, we see the FVM method as the best method. We compare the results of FVM with experimental data. Finite volume using staggered grid is applied for solving water hammer equations.

Keywords: hydraulic transient, water hammer, interpolation, non-liner interpolation

Procedia PDF Downloads 320
1280 Stability of Pump Station Cavern in Chagrin Shale with Time

Authors: Mohammad Moridzadeh, Mohammad Djavid, Barry Doyle

Abstract:

An assessment of the long-term stability of a cavern in Chagrin shale excavated by the sequential excavation method was performed during and after construction. During the excavation of the cavern, deformations of rock mass were measured at the surface of excavation and within the rock mass by surface and deep measurement instruments. Rock deformations were measured during construction which appeared to result from the as-built excavation sequence that had potentially disturbed the rock and its behavior. Also some additional time dependent rock deformations were observed during and post excavation. Several opinions have been expressed to explain this time dependent deformation including stress changes induced by excavation, strain softening (or creep) in the beddings with and without clay and creep of the shaley rock under compressive stresses. In order to analyze and replicate rock behavior observed during excavation, including current and post excavation elastic, plastic, and time dependent deformation, Finite Element Analysis (FEA) was performed. The analysis was also intended to estimate long term deformation of the rock mass around the excavation. Rock mass behavior including time dependent deformation was measured by means of rock surface convergence points, MPBXs, extended creep testing on the long anchors, and load history data from load cells attached to several long anchors. Direct creep testing of Chagrin Shale was performed on core samples from the wall of the Pump Room. Results of these measurements were used to calibrate the FEA of the excavation. These analyses incorporate time dependent constitutive modeling for the rock to evaluate the potential long term movement in the roof, walls, and invert of the cavern. The modeling was performed due to the concerns regarding the unanticipated behavior of the rock mass as well as the forecast of long term deformation and stability of rock around the excavation.

Keywords: Cavern, Chagrin shale, creep, finite element.

Procedia PDF Downloads 310
1279 Physiochemical and Antibacterial Assessment of Iranian Propolis Gathering in Qazvin Province

Authors: Nematollah Gheibi, Nader Divan Khosroshahi, Mahdi Mohammadi Ghanbarlou

Abstract:

Introduction: Nowadays, the phenomenon of bacterial resistance is one of the most important challenge of the health community in the world. Propolis is most important production of bee colonies that collected from of various plants. So far, a lot of investigations carried out about its antibacterial effects. Material and methods: Thirty gram of propolis prepared as ethanolic extract and after different process of purification, 7.5 gr of its pure form were obtained. Propolis compounds identification was performed by TLC and VLC methods. The HPLC spectrum obtaining from propolis ethanolic extract was compared with some purified standard phenolic and flavonoid substances. Antibacterial effects of ethanol extract of purified propolis were evaluated on two strains of Staphylococcus aureus and Pseudomonas aeruginosa and their MIC was determined by the microdillution assay. Results: Ethanolic propolis extraction analyzed by TLC were resulted to confirm several phenolic and flavonoid compounds in this extract and some of the confirmed by HPLC technique. Minimum inhibitory concentration (MIC) for standard Staphylococcus aureus (ATCC25923) and Pseudomonas aeruginosa (ATCC27853) strains were obtained 2.5 mg/ml and 50 mg/ml respectively. Conclusion: Bee Propolis is a mix organic compound that has a lot of beneficial effects such as anti-bacterial that emphasized in this investigation. It is proposed as a rich source of natural phenolic and flavonoids compounds in designing of new biological resources for hygienic and medical applications.

Keywords: propolis, Staphylococcus aureus, Pseudomonas aeruginosa, antibacterial

Procedia PDF Downloads 275
1278 Effective Stiffness, Permeability, and Reduced Wall Shear Stress of Highly Porous Tissue Engineering Scaffolds

Authors: Hassan Mohammadi Khujin

Abstract:

Tissue engineering is the science of tissues and complex organs creation using scaffolds, cells and biologically active components. Most cells require scaffolds to grow and proliferate. These temporary support structures for tissue regeneration are later replaced with extracellular matrix produced inside the body. Recent advances in additive manufacturing methods allow production of highly porous, complex three dimensional scaffolds suitable for cell growth and proliferation. The current paper investigates the mechanical properties, including elastic modulus and compressive strength, as well as fluid flow dynamics, including permeability and flow-induced shear stress of scaffolds with four triply periodic minimal surface (TPMS) configurations, namely the Schwarz primitive, the Schwarz diamond, the gyroid, and the Neovius structures. Higher porosity in all scaffold types resulted in lower mechanical properties. The permeability of the scaffolds was determined using Darcy's law with reference to geometrical parameters and the pressure drop derived from the computational fluid dynamics (CFD) analysis. Higher porosity enhanced permeability and reduced wall shear stress in all scaffold designs.

Keywords: highly porous scaffolds, tissue engineering, finite elements analysis, CFD analysis

Procedia PDF Downloads 48
1277 Evaluation of Oxidative Changes in Soybean Oil During Shelf-Life by Physico-Chemical Methods and Headspace-Liquid Phase Microextraction (HS-LPME) Technique

Authors: Maryam Enteshari, Kooshan Nayebzadeh, Abdorreza Mohammadi

Abstract:

In this study, the oxidative stability of soybean oil under different storage temperatures (4 and 25˚C) and during 6-month shelf-life was investigated by various analytical methods and headspace-liquid phase microextraction (HS-LPME) coupled to gas chromatography-mass spectrometry (GC-MS). Oxidation changes were monitored by analytical parameters consisted of acid value (AV), peroxide value (PV), p-Anisidine value (p-AV), thiobarbituric acid value (TBA), fatty acids profile, iodine value (IV), and oxidative stability index (OSI). In addition, concentrations of hexanal and heptanal as secondary volatile oxidation compounds were determined by HS-LPME/GC-MS technique. Rate of oxidation in soybean oil which stored at 25˚C was so higher. The AV, p-AV, and TBA were gradually increased during 6 months while the amount of unsaturated fatty acids, IV, and OSI decreased. Other parameters included concentrations of both hexanal and heptanal, and PV exhibited increasing trend during primitive months of storage; then, at the end of third and fourth months a sudden decrement was understood for the concentrations of hexanal and heptanal and the amount of PV, simultaneously. The latter parameters increased again until the end of shelf-time. As a result, the temperature and time were effective factors in oxidative stability of soybean oil. Also intensive correlations were found for soybean oil at 4 ˚C between AV and TBA (r2=0.96), PV and p-AV (r2=0.9), IV and TBA (-r2=0.9), and for soybean oil stored at 4˚C between p-AV and TBA (r2=0.99).

Keywords: headspace-liquid phase microextraction, oxidation, shelf-life, soybean oil

Procedia PDF Downloads 370
1276 Numerical Modeling of Turbulent Natural Convection in a Square Cavity

Authors: Mohammadreza Sedighi, Mohammad Said Saidi, Hesamoddin Salarian

Abstract:

A numerical study has been performed to investigate the effect of using different turbulent models on natural convection flow field and temperature distributions in partially heated square cavity compare to benchmark. The temperature of the right vertical wall is lower than that of heater while other walls are insulated. The commercial CFD codes are used to model. Standard k-w model provided good agreement with the experimental data.

Keywords: Buoyancy, Cavity, CFD, Heat Transfer, Natural Convection, Turbulence

Procedia PDF Downloads 313
1275 The Effects of Arginine, Glutamine and Threonine Supplementation in the Starting Phase on Subsequent Performance of Male Broile

Authors: Jalal Fazli Amiri, Mohammad Hossein Shahir, Mohammad Hossein Nemati, Afshin Heidarinia

Abstract:

The current study was performed to investigate the effects of arginine, threonine, and glutamine supplementation in excess of requirements in the starter period (17 days) on performance, intestinal morphology, and immune response of broilers. Four hundred and sixteen male day-old chicks were assigned in a 2×2×2 factorial arrangement to a completely randomized design with four replicates (13 birds per replicate ). Treatments were: a control group that received the basal diet, basal diet plus 1% glutamine, basal diet plus 0.2% threonine, basal diet plus 0.75 % arginine, and combination of these three amino acids (glutamine+arginine, glutamine+threonine, arginine+threonine and arginine+ glutamine+threonine). The effect of glutamine supplementation on feed intake was significant in week 4 (p < 0.05), week 6 (p < 0.001), and total feed intake (p < 0.05) and caused declined feed intake. No significant differences of glutamine addition were observed on intestinal morphology (villi height, crypt depth, villi height to crypt depth ratio, villi width). Threonine supplementation caused increased weight gain in week 2 (p < 0.001) and 3 and a decrease of total feed intake (p < 0.05). Duodenum and jejunum villi height, crypt depth, villi height to crypt depth ratio, villi width were not affected. The effect of arginine supplementation was the increase of breast percentage (p < 0.05) and a decrease of jejunum villi high (p < 0.05) and Jejunum crypt depth (p < 0.05). Supplementation of arginine, threonine, and glutamine had no significant effects on blood titer of antibodies against Newcastle disease, infectious bronchitis, avian influenza. Overall, it seems that the supplementation of arginine, threonine, and glutamine in excess of requirements in the starter period had no effect on performance in subsequent periods and intestinal morphology.

Keywords: intestinal morphology, immunity, broiler chickens, glutamine, arginine, threonine

Procedia PDF Downloads 105
1274 Automatic Approach for Estimating the Protection Elements of Electric Power Plants

Authors: Mahmoud Mohammad Salem Al-Suod, Ushkarenko O. Alexander, Dorogan I. Olga

Abstract:

New algorithms using microprocessor systems have been proposed for protection the diesel-generator unit in autonomous power systems. The software structure is designed to enhance the control automata of the system, in which every protection module of diesel-generator encapsulates the finite state machine.

Keywords: diesel-generator unit, protection, state diagram, control system, algorithm, software components

Procedia PDF Downloads 368
1273 Public Preferences and Willingness to Pay for Social Health Insurance in Iran: A Discrete Choice Experiment

Authors: Mohammad Ranjbar, Mohammad Bazyar, Blake Angell, Thomas Lung, Yibeltal Assefa

Abstract:

Background: Current health insurance programs in Iran suffer from low enrolment and are not sufficient to attain the country to universal health coverage (UHC). We hypothesize that improving the enrollment rate and moving towards a more sustainable UHC can be achieved by improving the benefits package and providing new incentives. The objective of this study is to assess public preferences and willingness to pay (WTP) for social health insurance (SHI) in Iran. Methods: A discrete choice experiment (DCE) was conducted in 2021, using a self-administered questionnaire on 500 participants to estimate WTP and determine individual preferences for the SHI in Yazd, Iran. Respondents were presented with an eight-choice set and asked to select their preferred one. In each choice set, scenarios were described by eight attributes with varying levels. The conditional logit regression model was used to analyze the participants' preferences. Willingness to pay for each attribute was also calculated. Results: Most included attributes were significant predictors of the choice of a health insurance package. The maximum coverage of hospitalization costs in the private sector, ancillary services such as glasses, canes, etc., as well as coverage for hospitalization costs in the public sector and drug costs, were the most important determining factors for this choice. Coverage of preventive dental care did not significantly influence respondent choices. Estimating WTP showed that individuals are willing to pay more for higher financial protection, particularly against private sector costs; the WTP to increase the coverage of hospitalization costs in the private sector from 50% to 90% is estimated at 362,068 IR, Rials per month. Conclusion: This study identifies the key factors that the population value with regard to health insurance and the tradeoffs they are willing to make between them. Hospitalization, drugs, and ancillary services were the most important determining factors for their choice. The data suggest that additional resources coming into the Iranian health system might best be prioritized to cover hospitalization and drug costs and those associated with ancillary services.

Keywords: social health insurance, preferences, discrete choice experiment, willingness to pay

Procedia PDF Downloads 52
1272 Misophonia and Its Relationship with Obsessive-compulsive Disorder, Anxiety, and Depression

Authors: Shahrzad Yektatalab, Agrin Mohammadi, Ladan Zarshenas

Abstract:

Background: Misophonia is a severe emotional response to repetitive sounds. This disorder may limit a person's communication, reduce their ability, or disrupt their social and personal life. This study aims to determine the prevalence of Misophonia and its relationship with obsessive-compulsive disorder, anxiety, and depression in undergraduate students of XXX University of Medical Sciences. Methods: The present study is an analytical descriptive study conducted in October 2020. The study samples are 390 undergraduate students of XXX University of medical sciences. A relative and systematic sampling method was used. In this study, a demographic questionnaire, misophonia questionnaire (A score of 7 or higher is considered as misophonia), Beck anxiety questionnaire, Beck depression questionnaire, and Maudsley questionnaire were used, and the data were analyzed using SPSS 24 software. Due to the non-normality of the data, the Spearman correlation coefficient was used for analyzing data. The significance level was considered less than 0.05. Results: 23.8% of students have misophonia. Of the 390 participants in the study, 93 had experienced misophonia. Among these 93 students, 37 (39.8%) had obsessive-compulsive disorder, 8 (8.6%) had anxiety and 9 (9.7%) had depression. There was a significant and direct relationship between all variables (p <0.001), which means that with the increase of each disorder, the probability of an increase in other disorders increases. Conclusion: Due to the high prevalence of misophonia in students and its direct relationship with obsessive-compulsive disorder, anxiety, and depression, It is recommended that future studies be conducted to identify ways to prevent and reduce the incidence of misophonia.

Keywords: misophonia, obsessive-compulsive disorder, anxiety, depression

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1271 Tram Track Deterioration Modeling

Authors: Mohammad Yousefikia, Sara Moridpour, Ehsan Mazloumi

Abstract:

Perceiving track geometry deterioration decisively influences the optimization of track maintenance operations. The effective management of this deterioration and increasingly utilized system with limited financial resources is a significant challenge. This paper provides a review of degradation models relevant for railroad tracks. Furthermore, due to the lack of long term information on the condition development of tram infrastructures, presents the methodology which will be used to derive degradation models from the data of Melbourne tram network.

Keywords: deterioration modeling, asset management, railway, tram

Procedia PDF Downloads 344
1270 Cryptography Based Authentication Methods

Authors: Mohammad A. Alia, Abdelfatah Aref Tamimi, Omaima N. A. Al-Allaf

Abstract:

This paper reviews a comparison study on the most common used authentication methods. Some of these methods are actually based on cryptography. In this study, we show the main cryptographic services. Also, this study presents a specific discussion about authentication service, since the authentication service is classified into several categorizes according to their methods. However, this study gives more about the real life example for each of the authentication methods. It talks about the simplest authentication methods as well about the available biometric authentication methods such as voice, iris, fingerprint, and face authentication.

Keywords: information security, cryptography, system access control, authentication, network security

Procedia PDF Downloads 431
1269 Computational Fluid Dynamic Modeling of Mixing Enhancement by Stimulation of Ferrofluid under Magnetic Field

Authors: Neda Azimi, Masoud Rahimi, Faezeh Mohammadi

Abstract:

Computational fluid dynamics (CFD) simulation was performed to investigate the effect of ferrofluid stimulation on hydrodynamic and mass transfer characteristics of two immiscible liquid phases in a Y-micromixer. The main purpose of this work was to develop a numerical model that is able to simulate hydrodynamic of the ferrofluid flow under magnetic field and determine its effect on mass transfer characteristics. A uniform external magnetic field was applied perpendicular to the flow direction. The volume of fluid (VOF) approach was used for simulating the multiphase flow of ferrofluid and two-immiscible liquid flows. The geometric reconstruction scheme (Geo-Reconstruct) based on piecewise linear interpolation (PLIC) was used for reconstruction of the interface in the VOF approach. The mass transfer rate was defined via an equation as a function of mass concentration gradient of the transported species and added into the phase interaction panel using the user-defined function (UDF). The magnetic field was solved numerically by Fluent MHD module based on solving the magnetic induction equation method. CFD results were validated by experimental data and good agreements have been achieved, which maximum relative error for extraction efficiency was about 7.52 %. It was showed that ferrofluid actuation by a magnetic field can be considered as an efficient mixing agent for liquid-liquid two-phase mass transfer in microdevices.

Keywords: CFD modeling, hydrodynamic, micromixer, ferrofluid, mixing

Procedia PDF Downloads 166
1268 Development of a Robot Assisted Centrifugal Casting Machine for Manufacturing Multi-Layer Journal Bearing and High-Tech Machine Components

Authors: Mohammad Syed Ali Molla, Mohammed Azim, Mohammad Esharuzzaman

Abstract:

Centrifugal-casting machine is used in manufacturing special machine components like multi-layer journal bearing used in all internal combustion engine, steam, gas turbine and air craft turboengine where isotropic properties and high precisions are desired. Moreover, this machine can be used in manufacturing thin wall hightech machine components like cylinder liners and piston rings of IC engine and other machine parts like sleeves, and bushes. Heavy-duty machine component like railway wheel can also be prepared by centrifugal casting. A lot of technological developments are required in casting process for production of good casted machine body and machine parts. Usually defects like blowholes, surface roughness, chilled surface etc. are found in sand casted machine parts. But these can be removed by centrifugal casting machine using rotating metallic die. Moreover, die rotation, its temperature control, and good pouring practice can contribute to the quality of casting because of the fact that the soundness of a casting in large part depends upon how the metal enters into the mold or dies and solidifies. Poor pouring practice leads to variety of casting defects such as temperature loss, low quality casting, excessive turbulence, over pouring etc. Besides these, handling of molten metal is very unsecured and dangerous for the workers. In order to get rid of all these problems, the need of an automatic pouring device arises. In this research work, a robot assisted pouring device and a centrifugal casting machine are designed, developed constructed and tested experimentally which are found to work satisfactorily. The robot assisted pouring device is further modified and developed for using it in actual metal casting process. Lot of settings and tests are required to control the system and ultimately it can be used in automation of centrifugal casting machine to produce high-tech machine parts with desired precision.

Keywords: bearing, centrifugal casting, cylinder liners, robot

Procedia PDF Downloads 380
1267 Further Development in Predicting Post-Earthquake Fire Ignition Hazard

Authors: Pegah Farshadmanesh, Jamshid Mohammadi, Mehdi Modares

Abstract:

In nearly all earthquakes of the past century that resulted in moderate to significant damage, the occurrence of postearthquake fire ignition (PEFI) has imposed a serious hazard and caused severe damage, especially in urban areas. In order to reduce the loss of life and property caused by post-earthquake fires, there is a crucial need for predictive models to estimate the PEFI risk. The parameters affecting PEFI risk can be categorized as: 1) factors influencing fire ignition in normal (non-earthquake) condition, including floor area, building category, ignitability, type of appliance, and prevention devices, and 2) earthquake related factors contributing to the PEFI risk, including building vulnerability and earthquake characteristics such as intensity, peak ground acceleration, and peak ground velocity. State-of-the-art statistical PEFI risk models are solely based on limited available earthquake data, and therefore they cannot predict the PEFI risk for areas with insufficient earthquake records since such records are needed in estimating the PEFI model parameters. In this paper, the correlation between normal condition ignition risk, peak ground acceleration, and PEFI risk is examined in an effort to offer a means for predicting post-earthquake ignition events. An illustrative example is presented to demonstrate how such correlation can be employed in a seismic area to predict PEFI hazard.

Keywords: fire risk, post-earthquake fire ignition (PEFI), risk management, seismicity

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1266 The Comparison of the Effect of Mindfulness-Based Relaxation Training and Trans Cranial Electrical Stimulation and Their Combination on Decreasing Physiological Distress in Patients with Type-2 Diabetes

Authors: Gholam Hossein Javanmard, Roghayeh Mohammadi Garegozlo

Abstract:

The present study was a randomized three-group double-blind clinical trial with repeated measures designs which aimed to determine the pure effect and combined effect of mindfulness based-relaxation (MBR) technique and Transcranial Electrical Simulation (tCES) on psychological distress decreasing of patients with type-2 diabetes. The sample of the study consisted of 30 patients with type-2 diabetes who were selected from the Diabetes Association of Bonab city in Iran. The participants were matched and then randomly assigned to the three groups of 10 subjects (MBR, CES, MBR+CES). The subjects received interventions related to their group in 10 individual sessions. Pre-test, post-test, and one-month follow-up were conducted using DASS-42. Analysis of variance with repeated measures showed a significant change in psychological distress. Multivariate covariance analysis and the paired interpersonal comparative test of Ben Foruni indicated that both interventions of MBR and CES have a similar effect on psychological distress decreasing in the post-test and follow-up phase. But, the combined therapy of MBR+CES was more efficient, and it had a more stable effect. However, all three interventions, especially combined intervention of MBR+CES, as efficient and stable treatment, are suggested for improving the psychological status of diabetic patients.

Keywords: mindfulness based-relaxation, transcranial electrical simulation, type 2 diabetes, psychological distress

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1265 Numerical Simulation of Laser ‎Propagation through Turbulent ‎Atmosphere Using Zernike ‎Polynomials

Authors: Mohammad Moradi ‎

Abstract:

In this article, propagation of a laser beam through turbulent ‎atmosphere is evaluated. At first the laser beam is simulated and then ‎turbulent atmosphere will be simulated by using Zernike polynomials. ‎Some parameter like intensity, PSF will be measured for four ‎wavelengths in different Cn2.

Keywords: laser beam propagation, phase screen, turbulent atmosphere, Zernike ‎polynomials

Procedia PDF Downloads 481
1264 Characterization of CuO Incorporated CMOS Dielectric for Fast Switching System

Authors: Nissar Mohammad Karim, Norhayati Soin

Abstract:

To ensure fast switching in high-K incorporated Complementary Metal Oxide Semiconductor (CMOS) transistors, the results on the basis of d (NBTI) by incorporating SiO2 dielectric with aged samples of CuO sol-gels have been reported. Precursor ageing has been carried out for 4 days. The minimum obtained refractive index is 1.0099 which was found after 3 hours of adhesive UV curing. Obtaining a low refractive index exhibits a low dielectric constant and hence a faster system.

Keywords: refractive index, Sol-Gel, precursor aging, aging

Procedia PDF Downloads 441
1263 The Diversity in the Concept of Existence from Kierkegaard to Sartre

Authors: Mohammad Motiee

Abstract:

From Kierkegaard to Sartre, the concept of 'being' was debated over various angles in the philosophy of being. Then, the futility, nothingness and absurdity of human condition in the world were all justified and led to a kind of solution by different approaches like Christianity, loss of faith, authentic existence and responsibility. In an extreme concern, the human condition in the world was pondered in different ways and the philosophy of thought tried to render an awareness of such condition for human beings. The present study aims at illustration of some approaches presented by prominent existentialists to justify the controversies in the concept of existence in human life.

Keywords: existence, existentialism, alienation, being

Procedia PDF Downloads 530
1262 Advancing Our Understanding of Age-Related Changes in Executive Functions: Insights from Neuroimaging, Genetics and Cognitive Neurosciences

Authors: Yasaman Mohammadi

Abstract:

Executive functions are a critical component of goal-directed behavior, encompassing a diverse set of cognitive processes such as working memory, cognitive flexibility, and inhibitory control. These functions are known to decline with age, but the precise mechanisms underlying this decline remain unclear. This paper provides an in-depth review of recent research investigating age-related changes in executive functions, drawing on insights from neuroimaging, genetics, and cognitive neuroscience. Through an interdisciplinary approach, this paper offers a nuanced understanding of the complex interplay between neural mechanisms, genetic factors, and cognitive processes that contribute to executive function decline in aging. Here, we investigate how different neuroimaging methods, like functional magnetic resonance imaging (fMRI) and positron emission tomography (PET), have helped scientists better understand the brain bases for age-related declines in executive function. Additionally, we discuss the role of genetic factors in mediating individual differences in executive functions across the lifespan, as well as the potential for cognitive interventions to mitigate age-related decline. Overall, this paper presents a comprehensive and integrative view of the current state of knowledge regarding age-related changes in executive functions. It underscores the need for continued interdisciplinary research to fully understand the complex and dynamic nature of executive function decline in aging, with the ultimate goal of developing effective interventions to promote healthy cognitive aging.

Keywords: executive functions, aging, neuroimaging, cognitive neuroscience, working memory, cognitive training

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1261 Subtidal Crabs of Oman Sea: New Collections and Biogeographic Considerations

Authors: Negar Ghotbeddin, Seied Mohammad Reza Fatemi, Tooraj Valinassab

Abstract:

The samplings were carried out at 8 stations (Govatr, Pasabandar, Beriss, Ramin, Chabahar, Pozm, Gordim, and Meidani) in subtidal zones of Oman Sea during the year 2009-2010. The specimens were collected by trawl net and preserved in 70% alcohol. A total of 23 species belonged to 9 families and 15 genera were caught. The results of the present study revealed that families Portunidae had the highest species enriched with 9 species. Most of the species had high distribution in the west Indian Ocean (69.56%) and 8.69% of species were endemic. Almost species were similar to those found in the Persian Gulf.

Keywords: Brachyura, biogeography, subtidal, Oman Sea

Procedia PDF Downloads 554
1260 Characterizing of CuO Incorporated CMOS Dielectric for Fast Switching System

Authors: Nissar Mohammad Karim, Norhayati Soin

Abstract:

To ensure fast switching in high-K incorporated Complementary Metal Oxide Semiconductor (CMOS) transistors, the results on the basis of d (NBTI) by incorporating SiO2 dielectric with aged samples of CuO sol-gels have been reported. Precursor ageing has been carried out for 4 days. The minimum obtained refractive index is 1.0099 which was found after 3 hours of adhesive UV curing. Obtaining a low refractive index exhibits a low dielectric constant and hence a faster system.

Keywords: refractive index, sol-gel, precursor ageing, metallurgical and materials engineering

Procedia PDF Downloads 346
1259 Fuglede-Putnam Theorem for ∗-Class A Operators

Authors: Mohammed Husein Mohammad Rashid

Abstract:

For a bounded linear operator T acting on a complex infinite dimensional Hilbert space ℋ, we say that T is ∗-class A operator (abbreviation T∈A*) if |T²|≥ |T*|². In this article, we prove the following assertions:(i) we establish some conditions which imply the normality of ∗-class A; (ii) we consider ∗-class A operator T ∈ ℬ(ℋ) with reducing kernel such that TX = XS for some X ∈ ℬ(K, ℋ) and prove the Fuglede-Putnam type theorem when adjoint of S ∈ ℬ(K) is dominant operators; (iii) furthermore, we extend the asymmetric Putnam-Fuglede theorem the class of ∗-class A operators.

Keywords: fuglede-putnam theorem, normal operators, ∗-class a operators, dominant operators

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1258 Comparison of Several Diagnostic Methods for Detecting Bovine Viral Diarrhea Virus Infection in Cattle

Authors: Azizollah Khodakaram- Tafti, Ali Mohammadi, Ghasem Farjanikish

Abstract:

Bovine viral diarrhea virus (BVDV) is one of the most important viral pathogens of cattle worldwide caused by Pestivirus genus, Flaviviridae family.The aim of the present study was to comparison several diagnostic methods and determine the prevalence of BVDV infection for the first time in dairy herds of Fars province, Iran. For initial screening, a total of 400 blood samples were randomly collected from 12 industrial dairy herds and analyzed using reverse transcription (RT)-PCR on the buffy coat. In the second step, blood samples and also ear notch biopsies were collected from 100 cattle of infected farms and tested by antigen capture ELISA (ACE), RT-PCR and immunohistochemistry (IHC). The results of nested RT-PCR (outer primers 0I100/1400R and inner primers BD1/BD2) was successful in 16 out of 400 buffy coat samples (4%) as acute infection in initial screening. Also, 8 out of 100 samples (2%) were positive as persistent infection (PI) by all of the diagnostic tests similarly including RT-PCR, ACE and IHC on buffy coat, serum and skin samples, respectively. Immunoreactivity for bovine BVDV antigen as brown, coarsely to finely granular was observed within the cytoplasm of epithelial cells of epidermis and hair follicles and also subcutaneous stromal cells. These findings confirm the importance of monitoring BVDV infection in cattle of this region and suggest detection and elimination of PI calves for controlling and eradication of this disease.

Keywords: antigen capture ELISA, bovine viral diarrhea virus, immunohistochemistry, RT-PCR, cattle

Procedia PDF Downloads 335