Search results for: Mohammad-Reza Ebrahimi

Authors: M. R. Ebrahimi, B. Mahdaviani

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Conventional electric distribution systems are radial in nature, supplied at one end through a main source. These networks generally have a simple protection system usually implemented using fuses, re-closers, and over-current relays. Recently, great attention has been paid to applying Distributed energy resources (DERs) throughout electric distribution systems. Presence of such generation in a network leads to losing coordination of protection devices. Therefore, it is desired to develop an algorithm which is capable of protecting distribution systems that include DER. On the other hand smart grid brings opportunities to the power system. Fast advancement in communication and measurement techniques accelerates the development of multi agent system (MAS). So in this paper, a new approach for the protection of distribution networks in the presence of DERs is presented base on MAS. The proposed scheme has been implemented on a sample 27-bus distribution network.

Keywords: distributed energy resource, distribution network, protection, smart grid, multi agent system

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Authors: Amirali Ebrahimi, T. A. G. Langrish

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The effect of various humidities on process yields and degrees of crystallinity for spray-dried powders from spray drying of lactose with humid air in a straight-through system have been studied. It has been suggested by Williams–Landel–Ferry kinetics (WLF) that a higher particle temperature and lower glass-transition temperature would increase the crystallization rate of the particles during the spray-drying process. Freshly humidified air produced by a Buchi-B290 spray dryer as a humidifier attached to the main spray dryer decreased the particle glass-transition temperature (Tg), while allowing the particle temperature (Tp) to reach higher values by using an insulated drying chamber. Differential scanning calorimetry (DSC) and moisture sorption analysis were used to measure the degree of crystallinity for the spray-dried lactose powders. The results showed that higher Tp-Tg, as a result of applying humid air, improved the process yield from 21 ± 4 to 26 ± 2% and crystallinity of the particles by decreasing the latent heat of crystallization from 43 ± 1 to 30 ± 11 J/g and the sorption peak height from 7.3 ± 0.7% to 6 ± 0.7%.

Keywords: lactose, crystallization, spray drying, humid air

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Authors: H. Ashrafi, S. Ebrahimi, H. Kamalzadeh

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With the development of business competition, it is important for healthcare providers to improve their service qualities. In order to improve service quality of a clinic, four important dimensions are defined: tangibles, responsiveness, empathy, and reliability. Moreover, there are several service stages in hospitals such as financial screening and examination. One of the most challenging limitations for improving service quality is budget which impressively affects the service quality. In this paper, we present an approach to address budget uncertainty and provide guidelines for service resource allocation. In this paper, a service quality improvement approach is proposed which can be adopted to multistage service processes to improve service quality, while controlling the costs. A multi-objective function based on the importance of each area and dimension is defined to link operational variables to service quality dimensions. The results demonstrate that our approach is not ultra-conservative and it shows the actual condition very well. Moreover, it is shown that different strategies can affect the number of employees in different stages.

Keywords: allocation, budget uncertainty, healthcare resource, service quality assessment, robust optimization

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Authors: Amin Ebrahimi Ghadi, Morteza Moalagh

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This research is carried out to find how a perfect combination of IoT architecture (Internet of Things) and ERP system can strengthen environmental accounting to incorporate both economic and environmental information. IoT (e.g., sensors, software, and other technologies) can be used in the company’s value chain from raw material extraction through materials processing, manufacturing products, distribution, use, repair, maintenance, and disposal or recycling products (Cradle to Grave model). The desired ERP software then will have the capability to track both midpoint and endpoint environmental impacts on a green supply chain system for the whole life cycle of a product. All these enable environmental accounting to calculate, and real-time analyze the operation environmental impacts, control costs, prepare for environmental legislation and enhance the decision-making process. In this study, we have developed a model on how to use IoT devices in life cycle assessment (LCA) to gather emissions, energy consumption, hazards, and wastes information to be processed in different modules of ERP systems in an integrated way for using in environmental accounting to achieve sustainability.

Keywords: ERP, environmental accounting, green supply chain, IOT, life cycle assessment, sustainability

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Authors: Fariba Ebrahimi, Mehdi Ghorbani

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Achieving to integrated Water management fundamentally needs to effective relation, coordination, collaboration and synergy among various actors who have common but different responsibilities. In this sense, the foundation of comprehensive and integrated management is not compatible with centralization and top-down strategies. The aim of this paper is analysis institutional network of water relevant stakeholders and water policy monitoring in Shemiranat. In this study collaboration networks between informal and formal institutions co-management process have been investigated. Stakeholder network analysis as a quantitative method has been implicated in this research. The results of this study indicate that institutional cohesion is medium; sustainability of institutional network is about 40 percent (medium). Additionally the core-periphery index has measured in this study according to reciprocity index. Institutional capacities for integrated natural resource management in regional level are measured in this study. Furthermore, the necessity of centrality reduction and promote stakeholders relations and cohesion are emphasized to establish a collaborative natural resource governance.

Keywords: policy monitoring, water management, social network, stakeholder, shemiranat

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Authors: Mehrji Khosravan, Mostafa Fathali-Sianib, Davood Soudbar, Sasan Talebnezhad, Mohammad-Reza Ebrahimi

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The late transition metal catalyst of the end group of transition metals in the periodic table as Ni, Fe, Co, and Pd was grown up rapidly in polyolefin industries recently. These metals with suitable ligands exhibited special characteristic properties and appropriate activities in the production of polyolefins. The ligand 1,4-bis (2,6-diisopropyl phenyl) acenaphthene was synthesized by reaction of 2,6-diisopropyl aniline and acenaphthenequinone. The ligand was added to nickel (II) dibromide salt for synthesis the 1,4-bis (2,6 diisopropylphenyl) acenaphthene nickel (II) dibromide catalyst. The structure of the ligand characterized by IR technique. The catalyst then deposited on graphene and graphene oxide by vander walss-attachment for use in Ethylene slurry polymerization process in the presence of catalyst activator such as methylaluminoxane (MAO) in hexane solvent. The structure of the catalyst characterized by IR and TEM techniques and some of the polymers were characterized by DSC. The highest activity was achieved at 600 C for catalyst.

Keywords: α-diimine nickel (II) complex, graphene as supported catalyst, late transition metal, ethylene polymerization

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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: B. Sabayan, A. Alidadi, S. Ebrahimi, N. M. Bakhshani

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Neuropsychological problems are more common in hemodialysis (HD) patients than in healthy individuals. The aim of this study was to investigate the effect of long term HD on memory types of HD patients. To assess the different type of memory, we used memory parts of the Persian Papers and Pencil Cognitive assessment package (PCAP) and Addenbrooke's Cognitive Examination (ACE-R). Our study included 80 HD patients of whom 39 had less than six months of HD and 41 patients and another group which had a history of HD more than six months. The population had a mean age of 51.60 years old and 27.5% of them were female. The scores of patients who have been hemodialyzed for a long time (median time of HD was up to 4 years) had lower score in anterograde, explicit, visual, recall and recognition memory (5.44±1.07, 9.49±3.472, 22.805±6.6913, 5.59±10.435, 11.02±3.190 score) than the HD patients who underwent HD for a shorter term, where the median time was 3 to 5 months (P<0.01). The regression result shows that, by increasing the HD duration, all memory types are reduced (R2=0.600, P<0.01). The present study demonstrated that HD patients who were under HD for a long time had significantly lower scores in the different types of memory. However, additional researches are needed in this area.

Keywords: hemodialysis patients, duration of hemodialysis, memory types, Zahedan

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Authors: Mohammadreza Nezamirad, Sepideh Amirahmadian, Nasim Sabetpour, Azadeh Yazdi, Amirmasoud Hamedi

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Cavitation inside the diesel injector nozzle is investigated numerically in this study. Reynolds Stress Navier Stokes set of equations (RANS) are utilized to investigate flow behavior inside the nozzle numerically. Moreover, K-ε turbulent model is found to be a better approach comparing to K-ω turbulent model. Winklhofer rectangular shape nozzle is also simulated in order to verify the current numerical scheme, and with, mass flow rate approach, the current solution is verified. Afterward, a six-hole real-size nozzle was simulated, and it was found that among different fuels used in this study with the same condition, diesel fuel provides the largest length of cavitation. Also, it was found that at the same boundary condition, RME fuel leads to the highest value of discharge coefficient and mass flow rate.

Keywords: cavitation, diesel fuel, CFD, real size nozzle, discharge coefficient

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Authors: Mehrdad Ebrahimi, Oliver Schmitz, Axel Schmidt, Peter Czermak

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“Produced water” (PW) is any fossil water that is brought to the surface along with crude oil or natural gas. By far, PW is the largest waste stream by volume associated with oil and gas production operations. Due to the increasing volume of waste all over the world in the current decade, the outcome and effect of discharging PW on the environment has lately become a significant issue of environmental concerns. Therefore, there is a need for new technologies for PW treatment due to increase focus on water conservation and environmental regulation. The use of membrane processes for treatment of PW has several advantages over many of the traditional separation techniques. In oilfield produced water treatment with ceramic membranes, process efficiency is characterized by the specific permeate flux and by the oil separation performance. Apart from the membrane properties, the permeate flux during filtration of oily wastewaters is known to be strongly dependent on the constituents of the feed solution, as well as on process conditions, e.g. trans-membrane pressure (TMP) and cross-flow velocity (CFV). The research project presented in these report describes the application of different ceramic membrane filtration technologies for the efficient treatment of oil-field produced water and different model oily solutions.

Keywords: ceramic membrane, membrane fouling, oil rejection, produced water treatment

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Authors: Nasrin Takzaree, Abbas Hadjiakhoondi, Gholamreza Hassanzadeh, Mohammadreza Rouini

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Background: Wound healing and repair is a normal reaction to injury which results in restoration of tissue integrity. Rate of wound healing is affected by various factors, such as nutrition, vitamins, hormones. Method: The aim of this study was to evaluate the effect of Aloe vera mucilage on wound healing. Mucilage was extracted from leaves, then homogenize, filtered and concentrated. Some creams were prepared with different concentrations of mucilage 95%. In this study 63 male albino rats, weighing 250–300 gr were used. Incision wounds (10 mm) were made on the shaved and cleaned back of rat necks. Wounds of case groups (group I & group II) were treated with aloe vera mucilage which were administered one time daily another group two times daily. Results: In order to evaluate wound healing, various parameters such as wound diameter, percentage of healing, duration of healing. Were considered. Conclusion: The results of this study confirmed that aloe vera mucilage is a potent healing and can be used in wound healing process.

Keywords: Aloe vera, wound healing, open skin wound, healing process

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Authors: Marzieh Ebrahimi, Vahid Changizi, Mohammad Reza Kardan, Seyed Mahdi Hosseini Pooya, Parham Geramifar

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Radiation exposure to the patient's family members is one of the major concerns during thyroid cancer radionuclide therapy. The aim of this study was to measure the total effective dose of the family members by means of thermoluminescence personal dosimeter, and compare with those calculated by analytical methods. Eighty-five adult family members of fifty-one patients volunteered to participate in this research study. Considering the minimum and maximum range of dose rate from 15 µsv/h to 120 µsv/h at patients' release time, the calculated mean and median dose values of family members were 0.45 mSv and 0.28 mSv, respectively. Moreover, almost all family members’ doses were measured to be less than the dose constraint of 5 mSv recommended by Basic Safety Standards. Considering the influence parameters such as patient dose rate and administrated activity, the total effective doses of family members were calculated by TEDE and NRC formulas and compared with those of experimental results. The results indicated that, it is fruitful to use the quantitative calculations for releasing patients treated with I-131 and correct estimation of patients' family doses.

Keywords: effective dose, thermoluminescence, I-131, thyroid cancer

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Authors: Shirin Manavi, Gorbanali Ebrahimi

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Man is a symbolist. He experiences living, whether he lived in the Old World or he is living in today's world. The symbol is a kind of concise expression of wishes and in the meantime, it comprises all the demands and Dos and Don'ts of a group, a people, and a nation. Our land, Iran, is also the land of symbols, explicit and hidden ones. The astronomical symbols are among these symbols that were recruited in fortune telling of cities. One of the symbols is the astronomical symbol of sagittairc which is the astrology of some cities such as Isfahan. November 22 of each year has been selected by Isfahan experts as Isfahan's Glorification Day. They have also selected the historically painted picture on the entrance of Qeysariye Bazar which has been designed based on the arch constellation. This symbol was chosen because Isfahan has been found in arch constellation on the basis of historical documentation of astrology. This study aims at the recognition, description, and analysis of the arch constellation, the symbol of Isfahan where it has been displayed once upon a time over the Tabarak castle and it is for centuries on the vertex of Isfahan's Qeysariye Bazar. This research has been done on the basis of the analytical method, but due to the particular structure of this paper, it has also benefited from the historical and descriptive methods.

Keywords: Isfahan's Qeysariye Bazar, semiotics, astrology of cities, constellation, sagittairc (Borje Ghos)

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Authors: Mohammadreza Nezamirad, Nasim Sabetpour, Azadeh Yazdi, Amirmasoud Hamedi

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In this study OpenFOAM 4.4.2 was used to investigate flow inside the coronary artery of the heart. This step is the first step of our future project, which is to include conjugate heat transfer of the heart with three main coronary arteries. Three different velocities were used as inlet boundary conditions to see the effect of velocity increase on velocity, pressure, and wall shear of the coronary artery. Also, three different fluids, namely the University of Wisconsin solution, gelatin, and blood was used to investigate the effect of different fluids on flow inside the coronary artery. A code based on Reynolds Stress Navier Stokes (RANS) equations was written and implemented with the real boundary condition that was calculated based on MRI images. In order to improve the accuracy of the current numerical scheme, hex dominant mesh is utilized. When the inlet velocity increases to 0.5 m/s, velocity, wall shear stress, and pressure increase at the narrower parts.

Keywords: CFD, simulation, OpenFOAM, heart

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Authors: M. Samsami, A. Hekmatdoost, N. Ebrahimi Daryani, P. Rezanejad Asl

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Ulcerative colitis (UC) is an inflammatory bowel disease in which immune and inflammatory factors are thought to be effective in this disease. Resveratrol is an antioxidant and anti-inflammatory compound. This study determined the effects of resveratrol compound on inflammatory factors in patients with ulcerative colitis. This study was a double-blind randomized clinical trial conducted on 50 patients with UC. Subjects received one capsule daily for 6 wk of either resveratrol (500 mg) or a placebo. Inflammatory factors, anthropometric measures, and IBDQ-9 (Inflammatory Bowel Disease Questionnaire-9) scores were assessed at baseline and at the end of the study. STATA12 software was used for data analysis. No significant differences were found in the background variables between the two groups at baseline. The results indicated that resveratrol supplementation for 6 week significantly decreased plasma levels of TNF-a and hs-CRP and the activity of NF-κB over the placebo group (p<0.001). Significant differences remained after adjustment for vitamin C (p<0.0001). The IBDQ-9 scores increased significantly in the resveratrol group over the placebo group (p<0.001). The findings of this study showed that resveratrol supplementation can be useful in patients with ulcerative colitis.

Keywords: IBD, inflammation, resveratrol, ulcerative colitis

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Authors: M. Rahimnejad, B. Vahidi, B. Ebrahimi Hoseinzadeh, F. Yazdian, P. Motamed Fath, R. Jamjah

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In this study, we developed and simulated nano-drug delivery systems efficacy in compare to free drug prescription. Computational models can be utilized to accelerate experimental steps and control the experiments high cost. Molecular dynamics simulation (MDS), in particular NAMD was utilized to better understand the anti-cancer drug interaction with cell membrane model. Paclitaxel (PTX) and dipalmitoylphosphatidylcholine (DPPC) were selected for the drug molecule and as a natural phospholipid nanocarrier, respectively. This work focused on two important interaction parameters between molecules in terms of center of mass (COM) and van der Waals interaction energy. Furthermore, we compared the simulation results of the PTX interaction with the cell membrane and the interaction of DPPC as a nanocarrier loaded by the drug with the cell membrane. The molecular dynamic analysis resulted in low energy between the nanocarrier and the cell membrane as well as significant decrease of COM amount in the nanocarrier and the cell membrane system during the interaction. Thus, the drug vehicle showed notably better interaction with the cell membrane in compared to free drug interaction with the cell membrane.

Keywords: anti-cancer drug, center of mass, interaction energy, molecular dynamics simulation, nanocarrier

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Authors: Saba Ebrahimi, Saeed Ahmadian, Hedie Ashrafi

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Selecting appropriate patients for surgery is one of the main issues in thoracic surgery (TS). Both short-term and long-term risks and benefits of surgery must be considered in the patient selection criteria. There are some limitations in the existing datasets of TS patients because of missing values of attributes and imbalanced distribution of survival classes. In this study, a novel ensemble architecture of deep learning networks is proposed based on stacking different linear and non-linear layers to deal with imbalance datasets. The categorical and numerical features are split using different layers with ability to shrink the unnecessary features. Then, after extracting the insight from the raw features, a novel biased-kernel layer is applied to reinforce the gradient of the minority class and cause the network to be trained better comparing the current methods. Finally, the performance and advantages of our proposed model over the existing models are examined for predicting patient survival after thoracic surgery using a real-life clinical data for lung cancer patients.

Keywords: deep learning, ensemble models, imbalanced classification, lung cancer, TS patient selection

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Authors: Seyed Ziya Tabatabaei, Azimi Bin Hj Hamzah, Fatemeh Ebrahimi

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The increase in proportion of older people in Malaysia has led to a significant growth of health care demands. The aim of this study is to explore how perceived health care needs influence on quality of life among elderly Malay residents who reside in a Malaysian residential home. This study employed a method known as ethnographic research from May 2011 to January 2012. Four data collection strategies were selected as the main data-collecting tools including participant observation, field notes, in-depth interviews, and review of related documents. The nine knowledgeable participants for the present study were selected using the purposive sampling method. Two themes were identified: (1) Medical concerns: Feeling secure, lack of information, inadequate medical staff; and (2) Health promotion: Body condition, health education, physiotherapy and rehabilitation. These results could evoke the attention of policy-makers and care providers to better meet elderly residents’ health care needs.

Keywords: ethnographic study, health care needs, Malay elderly people, Malaysia, Quality of life, Residential home

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Authors: Amirmozafar Benshams, Saman Shafeinejad, Mohammad Zaman Kabir, Farzad Hatami, Mohammadreza Khedmati, Mesbah Saybani

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Steel bars has been used in concrete structures for more than one hundred years but lack of corrosion resistance of steel reinforcement has resulted in many structural failures. Fiber Reinforced Polymer (FRP) bar is an acceptable solution to replace steel to mitigate corrosion problem. Since FRP is a brittle material its use in seismic region has been a concern. FRP RC structures can be made ductile by employing a ductile material such as Shape Memory Alloy (SMA) at the plastic hinge region and FRP at the other regions on the other hand SMA is highly resistant to corrosion. Shape Memory Alloy has the unique ability to undergo large inelastic deformation and regain its initial shape through stress removal therefore utilizing composite SMA-FRP bars not only have good corrosion resistance but also have good performance in seismic region. The result show indicate that such composite SMA-FRP bars can substantially reduce the residual drift with adequate energy dissipation capacity during earthquake.

Keywords: steel bar, shape memory alloy, FRP, corrosion

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Authors: M.Ayazi, N. Golshan Ebrahimi

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The development of antibacterial surface has devoted extensive researches and important field due to the growing antimicrobial resistance strains. The superhydrophobic surface has raised attention because of reducing bacteria adhesion in the absence of antibiotic agents. Evaluating the current development antibacterial surface has to be investigating to consider the potential of applying superhydrophobic surface to reduce bacterial adhesion or role of patterned surfaces on it. In this study, we present different samples with bio-inspired hierarchical and microstructures to consider their ability in reducing bacterial adhesion. The structures have inspired from rice-like pattern and lotus-leaf that developed on the polydimethylsiloxane (PDMS) and polypropylene (PP). The results of the attachment behaviors have considered on two bacteria strains of gram-negative Escherichia coli (E. coli) bacteria and gram-positive Staphylococcus aureus (S. aureus). The reduction of bacteria adhesion on these roughness surfaces demonstrated the effectiveness of rinsing ability on removing bacterial cells on structured plastic surfaces. Results have also offered the important role of bacterial species, material chemistry and hierarchical structure to prevent bacterial adhesion.

Keywords: hierarchical structure, self-cleaning, lotus-effect, bactericidal

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Authors: Mohammadreza Akbari, Pooya Soleimani Besheli, Reza Khalili, Sara Akbari

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In this study, we investigate building structures nonlinear behavior also solving analytic of nonlinear differential at vibrations. As we know most of engineering systems behavior in practical are non- linear process (especial at structural) and analytical solving (no numerical) these problems are complex, difficult and sometimes impossible (of course at form of analytical solving). In this symposium, we are going to exposure one method in engineering, that can solve sets of nonlinear differential equations with high accuracy and simple solution and so this issue will emerge after comparing the achieved solutions by Numerical Method (Runge-Kutte 4th) and exact solutions. Finally, we can proof AGM method could be created huge evolution for researcher and student (engineering and basic science) in whole over the world, because of AGM coding system, so by using this software, we can analytical solve all complicated linear and nonlinear differential equations, with help of that there is no difficulty for solving nonlinear differential equations.

Keywords: new method AGM, vibrations, beam-column, angular frequency, energy dissipated, critical load

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Authors: M. Ebrahimi, E. Maroufyan, M. Shakeri, E. Oskoueian, A. F Soleimani, Y. M. Goh

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Lipid peroxidation is a main reason of low quality in meat and meat products. The free radical chain reaction is the major process of lipid peroxidation and reactive oxygen species (ROS) such as hydroxyl radical and hydroperoxyl radical are the main starter of the chain reaction. Papaya leaf contains several secondary metabolites which can be used as a potential antioxidant in broiler feed. Hence, this research was carried out to evaluate the potential of papaya leaf to prevent lipid peroxidation and enhance the antioxidant activity of breast meat of broiler chicken. The results showed that supplementation of papaya leaf at 5%, significantly (p < 0.05) reduced the lipid peroxidation compared to control group. The supplementation of papaya leaf prevented from lipid peroxidation and enhanced the antioxidant activity of the broiler breast meat significantly (p < 0.05) after different storage periods. Papaya leaf reduced the lipid oxidation of meat during storage with strong free radical-scavenging ability. In conclusion, supplementation of papaya leaf in broiler diet to have high quality meat is recommended.

Keywords: antioxidant activity, papaya leaf, breast meat, lipid peroxidation

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Authors: Karim Farahmandfar, Hamidolah Izadi, Mohammadreza Rezaei, Amin Ardali, Ebrahim Goshtasbi Rad, Khosro Jafarpoor

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Statistics illustrates that the higher amount of annual energy consumption is related to surmounting the demand in buildings. Therefore, it is vital to economize the energy consumption and also find the solution with regard to this issue. One of the systems for the sake of heating the building is floor heating. As a matter of fact, floor heating performance is based on convection and radiation. Actually, in addition to creating a favorable heating condition, this method leads to energy saving. It is the goal of this article to outline the constructal theory and introduce the optimization method in branch networks for floor heating. There are several steps in order to gain this purpose. First of all, the pressure drop through the two points of the network is calculated. This pressure drop is as a function of pipes diameter and other parameters. After that, the amount of heat transfer is determined. Consequently, as a result of the combination of these two functions, the final function will be determined. It is necessary to mention that flow is laminar.

Keywords: constructal theory, optimization, floor heating system, turbulent flow

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Authors: Faezeh Mohammadi, Ebrahim Ebrahimi, Neda Azimi

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Use of ultrasound waves is one of the techniques for increasing the mixing and mass transfer in the microdevices. Ultrasound propagation into liquid medium leads to stimulation of the fluid, creates turbulence and so increases the mixing performance. In this study, CFD modeling of two-phase flow in a pitted micromixer equipped with a piezoelectric with frequency of 1.7 MHz has been studied. CFD modeling of micromixer at different velocity of fluid flow in the absence of ultrasound waves and with ultrasound application has been performed. The hydrodynamic of fluid flow and mixing efficiency for using ultrasound has been compared with the layout of no ultrasound application. The result of CFD modeling shows well agreements with the experimental results. The results showed that the flow pattern inside the micromixer in the absence of ultrasound waves is parallel, while when ultrasound has been applied, it is not parallel. In fact, propagation of ultrasound energy into the fluid flow in the studied micromixer changed the hydrodynamic and the forms of the flow pattern and caused to mixing enhancement. In general, from the CFD modeling results, it can be concluded that the applying ultrasound energy into the liquid medium causes an increase in the turbulences and mixing and consequently, improves the mass transfer rate within the micromixer.

Keywords: CFD modeling, ultrasound, mixing, mass transfer

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Authors: E. Oskoueian, E. Maroufyan, Y. M. Goh, E. Ramezani-Fard, M. Ebrahimi

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The fish meat plays an important role in the human health as it contains high quality protein. The tilapia fish considered as the third largest group of farmed fish. The oxidative deterioration of fish meat may occur during the cooking process. The proper cooking process and using natural antioxidant to prevent oxidation and enhance the quality of the tilapia fish fillet is necessary. Hence, this research was carried out to evaluate the potential of clove essential oil to prevent lipid peroxidation and enhance the antioxidant activity of tilapia fish fillet cooked using microwave and griller. The results showed that cooking using microwave significantly (p < 0.05) increased the lipid peroxidation and decreased the DPPH and ferric reducing activity power of the fish fillet as compared to grilling. The fortification of fish fillet using clove essential oil prevented from lipid peroxidation and enhanced the antioxidant activity of the fish fillet significantly (p < 0.05). Consequently, fortification of tilapia fish fillet using clove essential oil followed by cooking using griller to have high quality cooked fish meat is recommended.

Keywords: antioxidant activity, fillet, fish, fortification, lipid peroxidation

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Authors: Maedeh Rahimnejad, Bahman Vahidi, Bahman Ebrahimi Hoseinzadeh, Fatemeh Yazdian, Puria Motamed Fath, Roghieh Jamjah

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Introduction: The intensive labor and high cost of developing new vehicles for controlled drug delivery highlights the need for a change in their discovery process. Computational models can be used to accelerate experimental steps and control the high cost of experiments. Methods: In this work, to better understand the interaction of anti-cancer drug and the nanocarrier with the cell membrane, we have done molecular dynamics simulation using NAMD. We have chosen paclitaxel for the drug molecule and dipalmitoylphosphatidylcholine (DPPC) as a natural phospholipid nanocarrier. Results: Next, center of mass (COM) between molecules and the van der Waals interaction energy close to the cell membrane has been analyzed. Furthermore, the simulation results of the paclitaxel interaction with the cell membrane and the interaction of DPPC as a nanocarrier loaded by the drug with the cell membrane have been compared. Discussion: Analysis by molecular dynamics (MD) showed that not only the energy between the nanocarrier and the cell membrane is low, but also the center of mass amount decreases in the nanocarrier and the cell membrane system during the interaction; therefore they show significantly better interaction in comparison to the individual drug with the cell membrane.

Keywords: anti-cancer drug, center of mass, interaction energy, molecular dynamics simulation, nanocarrier

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Authors: Kambiz Hassanzadeh, Seyedeh Shohreh Ebrahimi, Shahrbanoo Oryan, Arman Rahimmi, Esmael Izadpanah

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Parkinson’s disease is one of the most prevalent neurodegenerative diseases which occurs in elderly. There are convincing evidences that oxidative stress has an important role in both the initiation and progression of Parkinson’s disease. Thymoquinone (TQ) is shown to have antioxidant and anti-inflammatory properties in invitro and invivo studies. It is well documented that TQ acts as a free radical scavenger and prevents the cell damage. Therefore this study aimed to evaluate the effect of TQ on motor and non-motor symptoms in animal model of Parkinson’s disease. Male Wistar rats (10-12 months) received rotenone (1mg/kg/day, sc) to induce Parkinson’s disease model. Pretreatment with TQ (7.5 and 15 mg/kg/day, po) was administered one hour before the rotenone injection. Three motor tests (rotarod, rearing and bar tests) and two non-motor tests (forced swimming and elevated plus maze) were performed for behavioral assessment. Our results indicated that TQ significantly ameliorated the rotenone-induced motor dysfunction in rotarod and rearing tests also it could prevent the non-motor dysfunctions in forced swimming and elevated plus maze tests. In conclusion we found that TQ delayed the Parkinson's disease induction by rotenone and this effect might be related to its proved antioxidant effect.

Keywords: Parkinson's disease, thymoquinone, motor and non-motor symptoms, neurodegenerative disease

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Authors: Mohammadreza Ashouri, Majid Bayatian

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Analysis of fire data is a way for the implementation of any plan to improve the level of safety in cities. Such an analysis is able to reveal signs of changes in a given period and can be used as a measure of safety. The information of about 66,341 fires (from 2002 to 2012) released by Tehran Safety Services and Fire-Fighting Organization and data on the population and the number of households provided by Tehran Municipality and the Statistical Yearbook of Iran were extracted. Using the data, the fire changes, the rate of injuries, and mortality rate were determined and analyzed. The rate of injuries and mortality rate of fires per one million population of Tehran were 59.58% and 86.12%, respectively. During the study period, the number of fires and fire stations increased by 104.38% and 102.63%, respectively. Most fires (9.21%) happened in the 4th District of Tehran. The results showed that the recorded fire data have not been systematically planned for fire prevention since one of the ways to reduce injuries caused by fires is to develop a systematic plan for necessary actions in emergency situations. To determine a reliable source for fire prevention, the stages, definitions of working processes and the cause and effect chains should be considered. Therefore, a comprehensive statistical system should be developed for reported and recorded fire data.

Keywords: fire statistics, fire analysis, accident prevention, Tehran

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Authors: Mohammadreza Judaki, Hosein Mohammadnezhad Shourkaei

Abstract:

Usually, noise generated by industrial units, is a pollution and disturbs people and causes problems for human health and sometimes these units will be closed because they cannot eliminate this pollution. Small-scale power plants usually are built close to residential areas, and noise generated by these power plants is an important factor in choosing their location and their design. Materials used to reduce noise are studied by measuring their absorption and reflection index numerically and experimentally. We can use MIKI model (Yasushi Miki, 1990) to simulate absorption index by using software like Ansys or Soundflow and compare calculation results with experimental simulation data. We consider high frequency sounds of power plant engines octave band diagram because dB value of high frequency noise is more noticeable for human ears. To prove this, in this study we first will study calculating octave band of engines exhausts and then we will study acoustic behavior of materials that we will use in high frequencies and this will give us our optimum noise reduction plan.

Keywords: acoustic materials, eliminating engine noise, octave level diagram, power plant noise

Procedia PDF Downloads 144

Authors: Erfan Ghasemi, Mohammadreza Khani, Hamidreza Mahmoudi, Mohammad Ali Nilforoushzadeh, Babak Shokri, Pouria Akbartehrani

Abstract:

Given the global significance of treating infectious wounds, the goal of this study is to use spark plasma as a new treatment for infectious wounds. To generate spark plasma, a high-voltage (7 kV) and high-frequency (75 kHz) source was used. Infectious wounds in the peritoneum of mice were divided into control and plasma-treated groups at random. The plasma-treated animals received plasma radiation every 4 days for 12 days, for 60 seconds each time. On the 15th day after the first session, the wound in the plasma-treated group had completely healed. The spectra of spark plasma emission and tissue properties were studied. The mechanical resistance of the wound healed in the plasma treatment group was considerably higher than in the control group (p<0.05), according to the findings. Furthermore, histological evidence suggests that wound re-epithelialization is faster in comparison to controls. Angiogenesis and fibrosis (collagen production) were also dramatically boosted in the plasma-treated group, whereas the stage of wound healing inflammation was significantly reduced. Plasma therapy accelerated wound healing by causing considerable wound constriction. The results of this investigation show that spark plasma has an influence on the treatment of infectious wounds.

Keywords: infectious wounds, mice, spark plasma, treatment

Procedia PDF Downloads 295