Search results for: Mohammad Reza Aref
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1763

Search results for: Mohammad Reza Aref

1133 Investigating the Insecticidal Effects of the Hexanic Extracts of Thymus spp. and Eucalyptus spp. on Cotton Bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae)

Authors: Reza Sadeghi, Maryam Nazarahari

Abstract:

Considering the effectiveness of plant pesticides in pest control, this group of pesticides can provide an efficient way to reduce the damage caused by pests in agriculture and maintain environmental health. Plant pesticides allow farmers to cultivate their crops by lowering the use of chemical pesticides and help improve the quality of agricultural products. In this research, various plant compounds were extracted from two different sources, thyme and eucalyptus, by using n-hexane solvent and investigated to control cotton bollworm in laboratory conditions. The mortality rates of cotton bollworm (Helicoverpa armigera) caused by different concentrations of hexanic extract formulations were evaluated. The results showed that the varied concentrations of the hexanic extract formulations of thyme and eucalyptus had significant effects on the mortality rates of cotton bollworm larvae during a 24-h exposure period. The hexanic extract of thyme as a plant pesticide can be an effective alternative in agriculture and plant pest control. The use of pesticides in agriculture can help the environment and reduce the problems related to chemical toxins. Also, this research revealed that the types and compounds of plant pesticides can be effective in pest control and help to develop more efficient agricultural strategies.

Keywords: cotton bollworm, thyme, eucalyptus, extract formulation, toxicity

Procedia PDF Downloads 89
1132 Comprehensive Investigation of Solving Analytical of Nonlinear Differential Equations at Chemical Reactions to Design of Reactors by New Method “AGM”

Authors: Mohammadreza Akbari, Pooya Soleimani Besheli, Reza khalili, Sara Akbari, Davood Domiri Ganji

Abstract:

In this symposium, our aims are accuracy, capabilities and power at solving of the complicate non-linear differential at the reaction chemical in the catalyst reactor (heterogeneous reaction). Our purpose is to enhance the ability of solving the mentioned nonlinear differential equations at chemical engineering and similar issues with a simple and innovative approach which entitled ‘’Akbari-Ganji's Method’’ or ‘’AGM’’. In this paper we solve many examples of nonlinear differential equations of chemical reactions and its investigate. The chemical reactor with the energy changing (non-isotherm) in two reactors of mixed and plug are separately studied and the nonlinear differential equations obtained from the reaction behavior in these systems are solved by a new method. Practically, the reactions with the energy changing (heat or cold) have an important effect on designing and function of the reactors. This means that possibility of reaching the optimal conditions of operation for the maximum conversion depending on nonlinear nature of the reaction velocity toward temperature, results in the complexity of the operation in the reactor. In this case, the differential equation set which governs the reactors can be obtained simultaneous solution of mass equilibrium and energy and temperature changing at concentration.

Keywords: new method (AGM), nonlinear differential equation, tubular and mixed reactors, catalyst bed

Procedia PDF Downloads 379
1131 Experimental Investigation on Effect of Different Heat Treatments on Phase Transformation and Superelasticity of NiTi Alloy

Authors: Erfan Asghari Fesaghandis, Reza Ghaffari Adli, Abbas Kianvash, Hossein Aghajani, Homa Homaie

Abstract:

NiTi alloys possess magnificent superelastic, shape memory, high strength and biocompatible properties. For improving mechanical properties, foremost, superelasticity behavior, heat treatment process is carried out. In this paper, two different heat treatment methods were undertaken: (1) solid solution, and (2) aging. The effect of each treatment in a constant time is investigated. Five samples were prepared to study the structure and optimize mechanical properties under different time and temperature. For measuring the upper plateau stress, lower plateau stress and residual strain, tensile test is carried out. The samples were aged at two different temperatures to see difference between aging temperatures. The sample aged at 500 °C has a bigger crystallite size and lower amount of Ni which causes the mentioned sample to possess poor pseudo elasticity behaviour than the other aged sample. The sample aged at 460 °C has shown remarkable superelastic properties. The mentioned sample’s higher plateau is 580 MPa with the lowest residual strain (0.17%) while other samples have possessed higher residual strains. X-ray diffraction was used to investigate the produced phases.

Keywords: heat treatment, phase transformation, superelasticity, NiTi alloy

Procedia PDF Downloads 130
1130 Role of Social Media for Institutional Branding: Ethics of Communication Review

Authors: Iva Ariani, Mohammad Alvi Pratama

Abstract:

Currently, the world of communication experiences a rapid development. There are many ways of communication utilized in line with the development of science which creates many technologies that encourage a rapid development of communication system. However, despite giving convenience for the society, the development of communication system is not accompanied by the development of applicable values and regulations. Therefore, it raises many issues regarding false information or hoax which can influence the society’s mindset. This research aims to know the role of social media towards the reputation of an institution using a communication ethics study. It is a qualitative research using interview, observation, and literature study for collecting data. Then, the data will be analyzed using philosophical methods which are hermeneutic and deduction methods. This research is expected to show the role of social media in developing an institutional reputation in ethical review.

Keywords: social media, ethics, communication, reputation

Procedia PDF Downloads 206
1129 Ownership Structure and Portfolio Performance: Pre- and Post-Crisis Evidence from the Amman Stock Exchange

Authors: Mohammad Q. M. Momani

Abstract:

The objective of this study is to examine whether the value relevance of ownership structure changed as the Amman Stock Exchange market conditions changed. Using data from 2005 to 2014, the study finds that the performance of portfolios that contain firms with concentrated ownership structure declines significantly during the post-crisis period. These portfolios exhibit poor performance relative to portfolios that contain firms with dispersed ownership structure during the post-crisis period. The results argue that uninspired performance of the Amman Stock Exchange during the post-crisis period, increased the incentives for controlling shareholders to expropriate. Investors recognized these incentives and discounted firms that were more likely to expropriate.

Keywords: value relevance, ownership structure, portfolio performance, Jordan, ASE

Procedia PDF Downloads 122
1128 Calculation of Stress Intensity Factors in Rotating Disks Containing 3D Semi-Elliptical Cracks

Authors: Mahdi Fakoor, Seyed Mohammad Navid Ghoreishi

Abstract:

Initiation and propagation of cracks may cause catastrophic failures in rotating disks, and hence determination of fracture parameter in rotating disks under the different working condition is very important issue. In this paper, a comprehensive study of stress intensity factors in rotating disks containing 3D semi-elliptical cracks under the different working condition is investigated. In this regard, after verification of modeling and analytical procedure, the effects of mechanical properties, rotational velocity, and orientation of cracks on Stress Intensity Factors (SIF) in rotating disks under centrifugal loading are investigated. Also, the effects of using composite patch in reduction of SIF in rotating disks are studied. By that way, the effects of patching design variables like mechanical properties, thickness, and ply angle are investigated individually.

Keywords: stress intensity factor, semi-elliptical crack, rotating disk, finite element analysis (FEA)

Procedia PDF Downloads 362
1127 Analysis of Hydraulic Velocity in Fishway Using CCHE2D Model

Authors: Amir Abbas Kamanbedast, Masood Mohammad Shafipor, Amir Ghotboddin

Abstract:

Fish way is a structure that in generally using to migrate to the place where they are spawned and is made near the spillway. Preventing fish spawning or migrating to their original place by fishway structures can affect their lives in the river or even erase one access to intended environment. The main objective of these structures is establishing a safe path for fish migration. In the present study first the hydraulic specifications of Hamidieh diversion dam were assessed and then it is problems were evaluated. In this study the dimensions of the fish way, including velocity of pools, were evaluated by CCHE2D software. Then by change slope in this structure streamlines like velocity in the pools were measured. For calibration can be use measuring local velocities in some pools. The information can be seen the fishway width of 0.3 m has minimum rate of descent in the total number of structures (pools and overflow).

Keywords: fishway, velocity, Hamidieh-Diversion Dam, CCHE2D model

Procedia PDF Downloads 490
1126 Household Food Insecurity, Maternal Mental Health and Self-Efficacy

Authors: Nahid Salarkia, Nasrin Omidvar, Erfan Ghassemi, Vahideh Arab-Salari, Tirang Reza Neyestani

Abstract:

Background: Household food insecurity has an adverse impact on the maternal mental health. This study was carried out to assess the relationship between household food insecurity, maternal depression and mother’s self-efficacy in Varamin, Iran, in 2014. Methods: In this cross-sectional study 423 mothers with children under 2 years old, with mean age 28.1±5.2 year; weight 66.3±13.4 kg; height 160.3± 5.7 cm and BMI 25.7±4.8 kg/m2 were selected by a multistage random sampling scheme. The instruments were: Beck Depression Inventory (BDI-III) and mother’s self-efficacy questionnaire. Data was analyzed using χ2 test, ANOVA and Pearson correlation. Results: Mildly, moderately and severely food insecure households were 39.5, 9.7 and 3.1%, respectively. Mild, moderate and sever depression was: 18.7, 13.9 and 5.7%. Mean score of depression in moderate and severe food insecure (8.6±5.3) was more than mild food insecure (4.8±4.7) and food secure (3.1±3.6) mothers. Frequency of very good, good and low mother’s self-efficacy were 62.8, 36.5, and 0.7%, respectively. Very good mother’s self-efficacy in food secure mothers (33.4%) was more than mild (25.4%) and moderate-sever food insecure groups (4%). There was a negative significant association between household food insecurity and mother’s self-efficacy (r= -0.297, p<0.01), and between mother’s depression and self-efficacy (r= -0.309, p=0.001). Conclusion: Empowerment of mothers with educational programs and social support can decrease mothers’ depression and increase self-efficacy that lead to improve maternal practices in food insecure households.

Keywords: Household food insecurity, Iran, mothers, physiological characteristics, self-efficacy

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1125 Impact of Saline Water and Water Restriction in Laying Hens

Authors: Reza Vakili

Abstract:

This experiment was conducted to investigate the effect of duration water restriction of drinking water and salinity level on production performance, egg quality and biochemical and hematological blood indices of laying hens. A total of 240 Hy-Line laying hens were used in a completely randomized design with a 2 × 2 factorial arrangement of treatments. Experimental treatments were: 1) free access to drinking water and a low level of salinity (TDS below 500 mg/L) (FAW+LS), 2) free access to water and a high level of salinity (TDS above 1500 mg/L), (FAW+HS), 3) 12 h nightly water restriction and a low level of salinity (LAW+LS), and 4) 12 h water restriction and a high level of salinity (LAW+HS). Intake of feed, percentage of egg production and egg weight and mass were not affected by water restriction or salinity level (P > 0.05), however, a trend (P < 0.01) for lower water consumption was detected in water-restricted hens, regardless of salinity level (213 vs 187). A tendency for lower eggshell and yolk weights was observed in hens that had limited access to water with high salinity compared to those had free access to high saline water (P = 0.08). Serum total protein and glucose concentrations significantly reduced (P < 0.05) in hens drank high salinity water, regardless of water restriction. Moreover, saline water increased the concentration of uric acid, creatinine, and cholesterol when compared to low salinity drank-hens (P < 0.05). The concentrations of ALT and AST increased with salinity level (P < 0.05) and water restriction caused an increment in AST content (P < 0.05). In conclusion, Hy-Line laying hens could withstand water restriction, whilst could not tolerate water salinity of about 1500 mg/L.

Keywords: chemical pollutants, eggs, laying hens, salinity, water quality

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1124 Fault Detection and Isolation in Sensors and Actuators of Wind Turbines

Authors: Shahrokh Barati, Reza Ramezani

Abstract:

Due to the countries growing attention to the renewable energy producing, the demand for energy from renewable energy has gone up among the renewable energy sources; wind energy is the fastest growth in recent years. In this regard, in order to increase the availability of wind turbines, using of Fault Detection and Isolation (FDI) system is necessary. Wind turbines include of various faults such as sensors fault, actuator faults, network connection fault, mechanical faults and faults in the generator subsystem. Although, sensors and actuators have a large number of faults in wind turbine but have discussed fewer in the literature. Therefore, in this work, we focus our attention to design a sensor and actuator fault detection and isolation algorithm and Fault-tolerant control systems (FTCS) for Wind Turbine. The aim of this research is to propose a comprehensive fault detection and isolation system for sensors and actuators of wind turbine based on data-driven approaches. To achieve this goal, the features of measurable signals in real wind turbine extract in any condition. The next step is the feature selection among the extract in any condition. The next step is the feature selection among the extracted features. Features are selected that led to maximum separation networks that implemented in parallel and results of classifiers fused together. In order to maximize the reliability of decision on fault, the property of fault repeatability is used.

Keywords: FDI, wind turbines, sensors and actuators faults, renewable energy

Procedia PDF Downloads 400
1123 Numerical Solution Speedup of the Laplace Equation Using FPGA Hardware

Authors: Abbas Ebrahimi, Mohammad Zandsalimy

Abstract:

The main purpose of this study is to investigate the feasibility of using FPGA (Field Programmable Gate Arrays) chips as alternatives for the conventional CPUs to accelerate the numerical solution of the Laplace equation. FPGA is an integrated circuit that contains an array of logic blocks, and its architecture can be reprogrammed and reconfigured after manufacturing. Complex circuits for various applications can be designed and implemented using FPGA hardware. The reconfigurable hardware used in this paper is an SoC (System on a Chip) FPGA type that integrates both microprocessor and FPGA architectures into a single device. In the present study the Laplace equation is implemented and solved numerically on both reconfigurable hardware and CPU. The precision of results and speedups of the calculations are compared together. The computational process on FPGA, is up to 20 times faster than a conventional CPU, with the same data precision. An analytical solution is used to validate the results.

Keywords: accelerating numerical solutions, CFD, FPGA, hardware definition language, numerical solutions, reconfigurable hardware

Procedia PDF Downloads 379
1122 New Effect of Duct Cross Sectional Shape on the Nanofluid Flow Heat Transfer

Authors: Mohammad R. Salimpour, Amir Dehshiri

Abstract:

In the present article, we investigate experimental laminar forced convective heat transfer specifications of TiO2/water nanofluids through conduits with different cross sections. we check the effects of different parameters such as cross sectional shape, Reynolds number and concentration of nanoparticles in stable suspension on increasing convective heat transfer by designing and assembling of an experimental apparatus. The results demonstrate adding a little amount of nanoparticles to the base fluid, improves heat transfer behavior in conduits. Moreover, conduit with circular cross-section has better performance compared to the square and triangular cross sections. However, conduits with square and triangular cross sections have more relative heat transfer enchantment than conduit with circular cross section.

Keywords: nano fluid, cross-sectional shape, TiO2, convection

Procedia PDF Downloads 520
1121 Comparative Analysis of Traditional and Modern Roundabouts Using Sidra Intersection

Authors: Amir Mohammad Parvini, Amir Masoud Rahimi

Abstract:

Currently, most parts of the world have shifted from traditional roundabouts to modern roundabouts with respect to the role of roundabouts in reducing accidents, increasing safety, lowering the maintenance costs compared to traffic circles with their improper functional and safety experiences. In this study, field data collected from a current traditional roundabout was analyzed by the software AIMSUN and the obtained numbers were recorded. The modern roundabout was designed by changes in the traditional one, considering the geometric standards listed in regulations. Then, the modern roundabout was analyzed by applying a heterogeneous traffic by a micro-simulation software SIDRA (5.1). The function, capacity, and safety of the roundabout were analyzed assuming the superiority of modern roundabouts and acceptable LOS. The obtained results indicate that the function, capacity, and safety of modern roundabouts are better than traditional ones.

Keywords: traditional roundabout, traffic circles, modern roundabout, AIMSUN, SIDRA

Procedia PDF Downloads 397
1120 Flame Dynamics in Small Scale Channels

Authors: Mohammed Mahmoud Osman Ahmed, Akram Mohammad

Abstract:

Flame dynamics in heated quartz glass channels of various aspect ratios (2,5,10,15) were experimentally investigated. A premixed Propane-air mixture was used for the reported experiments. Regarding micro-combustion, flame quenching is considered to be the most crucial problem to overcome first. Experiments were carried out on four channels with different aspect ratios. The results show that at a very low equivalence ratio ϕ=0.4, there is no flame inside the channels. The FREI condition (Flame with repetitive extinction and ignition) was overcome by increasing velocity and by making the channels more in contact with the external heater. The flame tested inside the channels at different locations for V=0.3 m/s or higher below V=0.65 m/s. The effects of equivalence ratio and flow velocity on the characteristics of combustion in the channels were examined. Different ways of flame propagation were observed in the current investigations based on how they appear as planar, concave and convex flames.

Keywords: flame stabilization, combustion, flame dynamics, small-scale channels, external heater

Procedia PDF Downloads 227
1119 Correlation of Strength and Change in the Thickness of Back Extensor Muscles during Maximal Isometric Contraction in Healthy and Osteoporotic Postmenopausal Women

Authors: Mohammad Jan-Nataj Zeinab, Kahrizi Sedighe, Bayat Noshin, Giti Torkaman

Abstract:

According to the importance of the back extensor muscle strength in postmenopausal women, this study aimed to determine the relationship between strength and changes in the thickness of back extensor muscles during isometric contraction in healthy and osteoporotic postmenopausal women. Strength and thickness of the muscles of 42 postmenopausal women were measured respectively, using a handheld dynamometer and ultrasonography. Also, the Pearson correlation coefficient was used to analyze the relationship between the strength and thickness. The results indicated a high reproducibility dynamometer test and ultrasonography. The decrease of strength in people with osteoporosis, occurred more through changes in muscle structure such as reducing the number and size of muscle fibers than changes in the nervous system part.

Keywords: back extensor muscles, strength, thickness, osteoporosis

Procedia PDF Downloads 260
1118 Prediction of the Lateral Bearing Capacity of Short Piles in Clayey Soils Using Imperialist Competitive Algorithm-Based Artificial Neural Networks

Authors: Reza Dinarvand, Mahdi Sadeghian, Somaye Sadeghian

Abstract:

Prediction of the ultimate bearing capacity of piles (Qu) is one of the basic issues in geotechnical engineering. So far, several methods have been used to estimate Qu, including the recently developed artificial intelligence methods. In recent years, optimization algorithms have been used to minimize artificial network errors, such as colony algorithms, genetic algorithms, imperialist competitive algorithms, and so on. In the present research, artificial neural networks based on colonial competition algorithm (ANN-ICA) were used, and their results were compared with other methods. The results of laboratory tests of short piles in clayey soils with parameters such as pile diameter, pile buried length, eccentricity of load and undrained shear resistance of soil were used for modeling and evaluation. The results showed that ICA-based artificial neural networks predicted lateral bearing capacity of short piles with a correlation coefficient of 0.9865 for training data and 0.975 for test data. Furthermore, the results of the model indicated the superiority of ICA-based artificial neural networks compared to back-propagation artificial neural networks as well as the Broms and Hansen methods.

Keywords: artificial neural network, clayey soil, imperialist competition algorithm, lateral bearing capacity, short pile

Procedia PDF Downloads 151
1117 Sustainable Development of Medium Strength Concrete Using Polypropylene as Aggregate Replacement

Authors: Reza Keihani, Ali Bahadori-Jahromi, Timothy James Clacy

Abstract:

Plastic as an environmental burden is a well-rehearsed topic in the research area. This is due to its global demand and destructive impacts on the environment, which has been a significant concern to the governments. Typically, the use of plastic in the construction industry is seen across low-density, non-structural applications due to its diverse range of benefits including high strength-to-weight ratios, manipulability and durability. It can be said that with the level of plastic consumption experienced in the construction industry, an ongoing responsibility is shown for this sector to continually innovate alternatives for application of recycled plastic waste such as using plastic made replacement from polyethylene, polystyrene, polyvinyl and polypropylene in the concrete mix design. In this study, the impact of partially replaced fine aggregate with polypropylene in the concrete mix design was investigated to evaluate the concrete’s compressive strength by conducting an experimental work which comprises of six concrete mix batches with polypropylene replacements ranging from 0.5 to 3.0%. The results demonstrated a typical decline in the compressive strength with the addition of plastic aggregate, despite this reduction generally mitigated as the level of plastic in the concrete mix increased. Furthermore, two of the six plastic-containing concrete mixes tested in the current study exceeded the ST5 standardised prescribed concrete mix compressive strength requirement at 28-days containing 1.50% and 2.50% plastic aggregates, which demonstrated the potential for use of recycled polypropylene in structural applications, as a partial by mass, fine aggregate replacement in the concrete mix.

Keywords: compressive strength, concrete, polypropylene, sustainability

Procedia PDF Downloads 140
1116 Investigating Relationship between Use of Mobile Technologies and Employees’ Creativity

Authors: Leila Niroomand, Reza Rafigh

Abstract:

Nowadays, the world is going under a dramatic change from an industry-centered society to an information-centered one. In other words, we are experiencing a transition from real, physical world into a virtual one. Stepping into the information age and running an effective life within the information-centered society demands getting acquainted with characteristics peculiar to such society. Recently, new technologies such as telecommunication and mobile technologies have changed vehemently and accumulation of achievements and information has become so important and brought about changes in occupational structures. The intellectual structure of this day and age depends on deep attention to creative and knowledge-based human resource collaboration instead of merely functioning human resource. Present study scrutinizes the contribution of different dimensions of mobile technologies including perceived use, perceived enjoyment, continuance intention, confirmation and satisfaction to the creativity of personnel. The statistical population included infrastructure communications company employees totaling 2431 persons out of which 331 individuals were chosen as sample based on Morgan and Krejcie table. This research is descriptive and the questionnaire was used for data gathering and it was distributed among those who used telegram application. 228 questionnaires were analyzed by the researcher. Applying SPSS software, Pierson correlation coefficient was analyzed and it was found out that all dimensions of mobile technologies except satisfaction correlate with the creativity of employees.

Keywords: mobile technologies, continuance intention, perceived enjoyment, confirmation, satisfaction, creativity, perceived use

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1115 Nanocrystalline Cellulose from Oil Palm Fiber

Authors: Ridzuan Ramli, Zianor Azrina Zianon Abdin, Mohammad Dalour Beg, Rosli M. Yunus

Abstract:

Nanocrystalline cellulose (NCC) were produced by using the ultrasound assisted acid hydrolysis from oil palm empty fruit bunch (EFB) pulp with different hydrolysis time then were analyzed by using FESEM and TGA as in comparison with EFB fiber and EFB pulp. Based on the FESEM analysis, it was found that NCC has a rod like shaped under the acid hydrolysis with an assistant of ultrasound. According to thermal stability, the NCC obtained show remarkable sign of high thermal stability compared to EFB fiber and EFB pulp. However, as the hydrolysis time increase, the thermal stability of NCC was deceased. As in conclusion, the NCC can be prepared by using ultrasound assisted acid hydrolysis. The NCC obtained have good thermal stability and have a great potential as the reinforcement in composite materials.

Keywords: Nanocrystalline cellulose, ultrasound assisted acid hydrolysis, thermal stability, morphology, empty fruit bunch (EFB)

Procedia PDF Downloads 476
1114 Screening of Nickel-Tolerant Genotype of Mung Bean (Vigna radiata) Based on Photosynthesis and Antioxidant System

Authors: Mohammad Yusuf, Qazi Fariduddin

Abstract:

The main aim of this study was to explore the different cultivars of Vigna radiata on basis of photosynthesis, antioxidants and proline to assess Ni-sensitive and Ni-tolerant cultivar. Seeds of five different cultivars were sown in soil amended with different levels of Ni (0, 50, 100, or 150 mg kg 1). At 30 d stage, plants were harvested to assess the various parameters. The Ni treatment diminished growth, leaf water potential, chlorophyll content and net photosynthesis along with nitrate reductase and carbonic anhydrase activities in the concentration dependent manner whereas, it enhanced proline content and various antioxidant enzymes. The varieties T-44 found least affected, whereas PDM-139 experienced maximum damage at 150 mg kg-1 of Ni. Moreover, T-44 possessed maximum activity of antioxidant enzymes and proline content at all the levels of metal whereas PDM-139 possessed minimum values. Therefore, T-44 and PDM-139 were established as the most resistant and sensitive varieties, respectively.

Keywords: Vigna radiata, antioxidants, nickel, photosynthesis, proline

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1113 Impact of Wheel-Housing on Aerodynamic Drag and Effect on Energy Consumption on an Bus

Authors: Amitabh Das, Yash Jain, Mohammad Rafiq B. Agrewale, K. C. Vora

Abstract:

Role of wheel and underbody aerodynamics of vehicle in the formation of drag forces is detrimental to the fuel (energy) consumption during the course of operation at high velocities. This paper deals with the CFD simulation of the flow around the wheels of a bus with different wheel housing geometry and pattern. Based on benchmarking a model of a bus is selected and analysis is performed. The aerodynamic drag coefficient is obtained and turbulence around wheels is observed using ANSYS Fluent CFD simulation for different combinations of wheel-housing at the front wheels, at the rear wheels and both in the front and rear wheels. The drag force is recorded and corresponding influence on energy consumption on an electric bus is evaluated mathematically. A comparison is drawn between energy consumption of bus body without wheel housing and bus body with wheel housing. The result shows a significant reduction in drag coefficient and fuel consumption.

Keywords: wheel-housing, CFD simulation, drag coefficient, energy consumption

Procedia PDF Downloads 182
1112 Dynamic vs. Static Bankruptcy Prediction Models: A Dynamic Performance Evaluation Framework

Authors: Mohammad Mahdi Mousavi

Abstract:

Bankruptcy prediction models have been implemented for continuous evaluation and monitoring of firms. With the huge number of bankruptcy models, an extensive number of studies have focused on answering the question that which of these models are superior in performance. In practice, one of the drawbacks of existing comparative studies is that the relative assessment of alternative bankruptcy models remains an exercise that is mono-criterion in nature. Further, a very restricted number of criteria and measure have been applied to compare the performance of competing bankruptcy prediction models. In this research, we overcome these methodological gaps through implementing an extensive range of criteria and measures for comparison between dynamic and static bankruptcy models, and through proposing a multi-criteria framework to compare the relative performance of bankruptcy models in forecasting firm distress for UK firms.

Keywords: bankruptcy prediction, data envelopment analysis, performance criteria, performance measures

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1111 High-Frequency Induction Heat Sintering of Al/SiC/GNS Nanocomposites and Their Tribological Properties

Authors: Mohammad Islam, Iftikhar Ahmad, Hany S. Abdo, Yasir Khalid

Abstract:

High-frequency induction heat sintering (HFIHS) is a fast, efficient powder consolidation technique. In this work, aluminum (Al) powder was mixed with silicon carbide (SiC) and/or graphene nanosheets (GNS) in different proportions and compacted using HFIHS process to produce dense nanocomposites. The nanostructures dispersion was assessed via electron microscopy using both SEM and TEM. Tribological behavior of the nanocomposites was investigated at different loads to determine wear rate and coefficient of friction. The scratch profiles were examined under the microscope to correlate wear properties with the microstructure. While the addition of SiC nanoparticles enhances microhardness values, GNS incorporation promotes dry lubricity with strikingly different wear scratch morphologies. Such Al/SiC/GNS material compositions can be explored for use in automotive brake pad and thermal management applications.

Keywords: aluminum nanocomposites, silicon carbide, graphene nanosheets, tribology

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1110 An Optimization Algorithm for Reducing the Liquid Oscillation in the Moving Containers

Authors: Reza Babajanivalashedi, Stefania Lo Feudo, Jean-Luc Dion

Abstract:

Liquid sloshing is a crucial problem for the dynamic of moving containers in the packaging industries. Sloshing issues have been so far mainly modeled within the framework of fluid dynamics or by using equivalent mechanical models with different kinds of movements and shapes of containers. Nevertheless, these approaches do not allow to determinate the shape of the free surface of the liquid in case of the irregular shape of the moving containers, so that experimental measurements may be required. If there is too much slosh in the moving tank, the liquid can be splashed out on the packages. So, the free surface oscillation must be controlled/reduced to eliminate the splashing. The purpose of this research is to propose an optimization algorithm for finding an optimum command law to reduce surface elevation. In the first step, the free surface of the liquid is simulated based on the separation variable and weak formulation models. Then Genetic and Gradient algorithms are developed for finding the optimum command law. The optimum command law is compared with existing command laws, and the results show that there is a significant difference in surface oscillation between optimum and existing command laws. This algorithm is applicable for different varieties of bottles in case of using the camera for detecting the liquid elevation, and it can produce new command laws for different kinds of tanks to reduce the surface oscillation and remove the splashing phenomenon.

Keywords: sloshing phenomenon, separation variables, weak formulation, optimization algorithm, command law

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1109 Flowsheet Development, Simulation and Optimization of Carbon-Di-Oxide Removal System at Natural Gas Reserves by Aspen–Hysys Process Simulator

Authors: Mohammad Ruhul Amin, Nusrat Jahan

Abstract:

Natural gas is a cleaner fuel compared to the others. But it needs some treatment before it is in a state to be used. So natural gas purification is an integral part of any process where natural gas is used as raw material or fuel. There are several impurities in natural gas that have to be removed before use. CO2 is one of the major contaminants. In this project we have removed CO2 by amine process by using MEA solution. We have built up the whole amine process for removing CO2 in Aspen Hysys and simulated the process. At the end of simulation we have got very satisfactory results by using MEA solution for the removal of CO2. Simulation result shows that amine absorption process enables to reduce CO2 content from NG by 58%. HYSYS optimizer allowed us to get a perfect optimized plant. After optimization the profit of existing plant is increased by 2.34 %.Simulation and optimization by Aspen-HYSYS simulator makes available us to enormous information which will help us to further research in future.

Keywords: Aspen–Hysys, CO2 removal, flowsheet development, MEA solution, natural gas optimization

Procedia PDF Downloads 497
1108 Concept and Implementation of Religious Tourism as a City Icon; Case Study: Golden Dome Mosque in Depok, Indonesia

Authors: Azhari Fauzan

Abstract:

Dian Al Mahri Mosque or more known as Golden Dome Mosque is one of the biggest mosques in Southeast Asia which located in Depok, West Java Province, Indonesia. Instead of a place for praying, this beautiful Mosque is also becoming an icon of Depok for religious tourism destination. The purpose of this study is to understand the concept and objective of religious tourism, also how to be implemented as an icon of the city. As a qualitative method, the data was collected by direct interview with three of the most influential persons: K. H. Amirudin Said S. Q. MA as a Manager of the Mosque, K. H. Dr. Mohammad Idris, MA as a Major of Depok, and Mulyamto as a Head of Tourism Department of Depok. As a result, Golden Dome Mosque involves three integrated aspects (social, economic, and cultural) which can be implemented to evaluate their daily activities and services in order to define themselves as a religious tourism destination.

Keywords: city icon, golden mosque, Muslim Indonesia, religious tourism

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1107 [Keynote Talk]: Formal Specification and Description Language and Message Sequence Chart to Model and Validate Session Initiation Protocol Services

Authors: Sa’ed Abed, Mohammad H. Al Shayeji, Ovais Ahmed, Sahel Alouneh

Abstract:

Session Initiation Protocol (SIP) is a signaling layer protocol for building, adjusting and ending sessions among participants including Internet conferences, telephone calls and multimedia distribution. SIP facilitates user movement by proxying and forwarding requests to the present location of the user. In this paper, we provide a formal Specification and Description Language (SDL) and Message Sequence Chart (MSC) to model and define the Internet Engineering Task Force (IETF) SIP protocol and its sample services resulted from informal SIP specification. We create an “Abstract User Interface” using case analysis so that can be applied to identify SIP services more explicitly. The issued sample SIP features are then used as case scenarios; they are revised in MSCs format and validated to their corresponding SDL models.

Keywords: modeling, MSC, SDL, SIP, validating

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1106 Biobutanol Production from Date Palm Waste by Clostridium acetobutylicum

Authors: Diya Alsafadi, Fawwaz Khalili, Mohammad W. Amer

Abstract:

Butanol is an important industrial solvent and potentially a better liquid transportation biofuel than ethanol. The cost of feedstock is one key problem associated with the biobutanol production. Date palm is sugar-rich fruit and highly abundant. Thousands of tons of date wastes that generated from date processing industries are thrown away each year and imposing serious environmental problems. To exploit the utilization of renewable biomass feedstock, date palm waste was utilized for butanol production by Clostridium acetobutylicum DSM 1731. Fermentation conditions were optimized by investigating several parameters that affect the production of butanol such as temperature, substrate concentration and pH. The highest butanol yield (1.0 g/L) and acetone, butanol, and ethanol (ABE) content (1.3 g/L) were achieved at 20 g/L date waste, pH 5.0 and 37 °C. These results suggest that date palm waste can be used for biobutanol production.

Keywords: biofuel, acetone-butanol-ethanol fermentation, date palm waste, Clostridium acetobutylicum

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1105 Depiction of a Circulated Double Psi-Shaped Microstrip Antenna for Ku-Band Satellite Applications

Authors: M. Naimur Rahman, Mohammad Tariqul Islam, Mandeep Singh Jit Singh, Norbahiah Misran

Abstract:

This paper presents the architecture and exploration of a compact, circulated double Psi-shaped microstrip patch antenna for Ku-band satellite applications. The antenna is composed of the double Psi-shaped patch in opposite focus which is circulated with a ring. The antenna size is 24 mm × 18 mm and the prototype is imprinted on Rogers RT/duroid 5880 materials with the depth of 1.57 mm. The substrate has a relative permittivity of 2.2 and the dielectric constant of 0.0009. The excitation is supplied through a 50Ω microstrip line. The performance of the presented antenna has been simulated and verified with the High-Frequency Structural Simulator (HFSS). The results depict that the antenna covers the frequency spectrum 14.6 - 17.4 GHz (Ku-band) with 10 dB return loss. The antenna has a 4.40 dBi maximum gain with stable radiation patterns throughout the operating band which makes the proposed antenna compatible for the satellite application in Ku-band.

Keywords: Ku-band antenna, microstrip antenna, psi-shaped antenna, satellite applications

Procedia PDF Downloads 308
1104 Performance Evaluation and Planning for Road Safety Measures Using Data Envelopment Analysis and Fuzzy Decision Making

Authors: Hamid Reza Behnood, Esmaeel Ayati, Tom Brijs, Mohammadali Pirayesh Neghab

Abstract:

Investment projects in road safety planning can benefit from an effectiveness evaluation regarding their expected safety outcomes. The objective of this study is to develop a decision support system (DSS) to support policymakers in taking the right choice in road safety planning based on the efficiency of previously implemented safety measures in a set of regions in Iran. The measures considered for each region in the study include performance indicators about (1) police operations, (2) treated black spots, (3) freeway and highway facility supplies, (4) speed control cameras, (5) emergency medical services, and (6) road lighting projects. To this end, inefficiency measure is calculated, defined by the proportion of fatality rates in relation to the combined measure of road safety performance indicators (i.e., road safety measures) which should be minimized. The relative inefficiency for each region is modeled by the Data Envelopment Analysis (DEA) technique. In a next step, a fuzzy decision-making system is constructed to convert the information obtained from the DEA analysis into a rule-based system that can be used by policy makers to evaluate the expected outcomes of certain alternative investment strategies in road safety.

Keywords: performance indicators, road safety, decision support system, data envelopment analysis, fuzzy reasoning

Procedia PDF Downloads 351