فهرست مطالب

International Journal of Engineering
Volume:30 Issue: 7, July 2017

  • TRANSACTIONS A: Basics
  • تاریخ انتشار: 1396/05/18
  • تعداد عناوین: 21
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  • N. Moosaviana, H. Moosavian Pages 926-936
    Recently, many meta-heuristic algorithms are proposed for optimization of various problems. Some of them originally are presented for continuous optimization problems and some others are just applicable for discrete ones. In the literature, sizing optimization of truss structures is one of the discrete optimization problems which is solved by many meta-heuristic algorithms. In this paper, in order to discover an efficient and reliable algorithm for optimization of truss structures, a discrete optimizer, entitled Soccer League Competition (SLC) algorithm and ten popular and powerful solvers are examined and statistical analysis is carried out for them. The fundamental idea of SLC algorithm is inspired from a professional soccer league and based on the competitions among teams to achieve better ranking and players to be the best. For optimization purpose and convergence of the initial population to the global optimum, different teams compete to take the possession of the best rating positions in the league table and the internal competitions are taken place between players in each team for personal improvements. Recently, SLC as a multi-population algorithm with developed operators has been applied for optimization of various problems. In this paper, for demonstrating the performance of the different solvers for optimal design of truss structures, five numerical examples will be optimized and the results show that proposed SLC algorithm is able to find better solutions among other algorithms. In other words, SLC can discover new local optimal solutions for some examples where other algorithms fail to find that one.
    Keywords: optimization of truss, global algorithm, soccer league competition, meta-heuristic algorithms
  • Z. Daud, M. Hijab Abubakar, A. Abdul Kadir, Ab A. Abdul Latiff, H. Awang, A. Abdul Halim, A. Marto Pages 937-944
    Landfills generate leachate that contains elevated concentration of contaminants and is hazardous to human health and the ecosystem. In this study, the mixture of granular activated carbon and cockle shells was investigated for remediation of COD and ammonia from stabilized landfill leachate. All adsorbent media were sieved to a particle size between 2.00 and 3.35 mm. The optimum mixing ratio, shaking speed, shaking time, pH, and dosage were determined. Characterization results show that the leachate had a high concentration of COD (1763 mg/L), ammonia nitrogen (573 mg/L), and BOD5/COD ratio (0.09). The optimum mixing ratio of granular activated carbon and cockle shells was 20:20, shaking speed 150 rpm, pH level 6, shaking time 120 min, and dosage 32 g. The adsorption isotherm analysis reveals that the Langmuir isotherm yielded the best fit to experimental data as compared with the Freundlich isotherm. The media produce encouraging results and can be used as a good and economical adsorbent.
    Keywords: Activated carbon, Cockle shells, economical adsorbent, Leachate, Optimum parameters, Isotherms
  • Y. Menasria Nouaouriaa, M. Brahimi Pages 945-954
    Fragility curves are very useful in quantifying the physical and economic damage of buildings that have undergone an earthquake. This paper presents the development of analytical fragility curves representative of mid-rise residential structures built with reinforced concrete, taking into account the specific structural characteristics of Algerian buildings. The derivation of the analytical fragility curves is based on the capacity spectrum method (CSM), which combines a non-linear static analysis (pushover) with a response spectrum analysis. Observation of the consequences of earthquakes of a given intensity shows that the damage to buildings is not identical, even though their construction is similar. This variability of damage can be explained by the variability of a large number of factors such as the local intensity of the hazard, the heterogeneity of the terrain, and the mechanical and geometrical characteristics of the constructions. The materials and patterns of demand spectra were considered as random variables using the Latin Hypercube Sampling Technique. Most of the existing methods that model the damage to structures accept a log-normal distribution hypothesis, where the log-normal law is a model controlled by two parameters: its mean value and its standard deviation. To set these parameters, Monte Carlo simulations (MCS) are performed to generate 1000 samples. The resulting fragility curves following these analyses were applied to two real-life cases of buildings affected by the earthquake of Beni-Ilmane 2010 (Msila, Algeria), so as to assess the damage.
    Keywords: fragility curves, seismic vulnerability, nonlinear analysis, performance levels, seismic response spectrum, pushover
  • D. B. Zhang, Y. Zhang, T. Cheng, J. Y. Yuan Pages 955-963
    Reducing the settlements of soft foundation effectively is a critical problem of high-speed railway construction in China. The new CFG pile-slab structure composite foundation is a ground treatment technique which is applied on CFG pile foundation and pile-slab structure composite foundation. Based on the experience of constructing Beijing-Shanghai high-speed railway in China, the settlement-controlling effect, the settlement distribution laws and three key influence factors for structural form of new CFG pile-slab structural foundation are studied by using physical model tests and numerical simulations. The research results in this study indicate that the piles and soil bearing capacities of the new CFG pile-slab structure can be put into full play because of the “load distributing” function of slabs. The settlement reducing effect of the new CFG pile-slab structure is remarkable and can meet the requirements of high-speed railway construction. The affected area of engineering load has a depth over 18.75 m and horizontal length of 7.5 m nearing the embankment slope toe. The parametric study provides the optimalizing structural form for best settlement-controlling effect. The physical model test results show good concordance with the numerical simulation results. The combination of physical model tests and numerical simulations justifies the use of this model in geotechnical engineering practices.
    Keywords: CFG pile-slab structure, settlement, numerical simulation, model test
  • B. Rath, S. Deo, G. Ramtekkar Pages 964-971
    Durability of concrete structure in marine environments is a big issue for many decades due to chloride attack. Chloride penetrates the concrete structure and accelerates the corrosion process of reinforcement which decreases the life of those structures. Also shrinkage cracks in concrete play main role for chloride penetration through concrete surface. Many researchers tried to find easy and economical ways to obtain durable concrete in such marine region by use of supplementary cementitious material with proper curing regime. Also use of fiber in concrete may arrest the shrinkage cracks, decreasing the chloride permeability and increasing the durability of concrete. Durability of concrete with glass fiber and by replacement of cement and sand partially by supplementary cementitious material such as fly ash and pond ash, respectively is measured by conducting shrinkage test, bulk electrical resistivity, SEM and ultrasonic pulse velocity test. Based on various test result present research proposes an economical durable concrete with desired compressive strength by use of glass fiber and supplementary cementitious material.
    Keywords: Fly ash, Pond ash, Glass fiber, Shrinkage Test, Electrical Resistivity Test, Ultrasonic Pulse Velocity Test
  • F. Kassou, J. Benbouziyane, A. Ghafiri, A. Sabihi Pages 972-980
    In this paper, a study was carried out in order to estimate settlements and consolidation rates under embankments constructed on Moroccan soft soils. Settlement measurements in several embankments in High Speed Railway project between two Moroccan cities, Tangier and Assilah, were analyzed. The objective of this study is to estimate settlement values and settlement rates, with sufficient precision, in soft soils under embankment loadings. It was found that the elastic method using the pressuremeter modulus results in more accurate settlement values than the oedometric method. Furthermore, settlement rates could be determined with fair accuracy by using a correlation between the vertical coefficient of consolidation and the liquid limit, and also by considering an isotropic behavior of soil.
    Keywords: Soft soil, Consolidation, Vertical drains, Preload, High Speed Railway, embankment
  • N. Bahrami, N. H. Haji Khamis, A. Yahya, A. Baharom Pages 981-987
    This study evaluates the impact of underwater ambient noise using seven real noise samples; Dolphin, Rain, Ferry, Sonar, Bubbles, Lightning, and Outboard Motor in three frequency ranges in extremely low frequency (ELF) band. The ELF band is the most significant bandwidth for underwater long-range communication. ELF band which is extended from 3 to 3000 Hz clearly, faces bandwidth limitation. Measuring the impact of noises that are imposed on this bandwidth, based on center frequency employment is highly regarded. This measurement optimizes detection process and assists the design of more reliable underwater communication systems and will improve network quality of service (QoS). In this investigation, Quadraphase Phase-shift Keying (QPSK) acoustic communication nodes are designed in MATLAB and real noise samples are added to network link. Three frequency bands are defined (0-1600), (400-2000) and (1600-3200) Hz, then the impact of noise samples on phase is measured. Next, ( ) ratio for every bandwidth (BW) is simulated. The result demonstrates 0 to 1600 Hz band is the nosiest part of the ELF band. This study discovered the Bubble noise sample from the environmental noise; Ferry from man-made noise and the Dolphin in mammal’s noise have the greatest impact on 0 to 1600 Hz bandwidth.
    Keywords: Underwater sensor network, Underwater ambient noise, Phase-shifting measurement, Underwater channel estimation, Acoustic QPSK link
  • I. A. Murdas Pages 988-994
    This paper proposes an analytical model for evaluating the performance of dense wavelength division multiplexing (DWDM) for all optical orthogonal frequency division multiplexing (AO-OFDM) optical wireless channel. The investigated performance for proposed system is evaluated for the parameters bit error rate (BER) and Q factor .The constellation diagrams, and bit error rate (BER) of the received signals are specified. The effect of atmospheric attenuation of the outdoor wireless optical communication system was induced (channel impairments) such as medium rain , light rain , and dust to find their effects on system performance carrier wavelength. The results show the BER and constellation diagram under different weather conditions for different transmission distance using Quadrature Amplitude Modulation (QAM) AO-OFDM-optical wireless channel (OWC).
    Keywords: DWDM, AO-OFDM, QAM, OWC
  • H. Sabahno, A. Amiri Pages 995-1004
    The effect of measurement errors on adaptive and non-adaptive control charts has been occasionally considered by researchers throughout the years. However, that effect on the variable sample size and sampling interval (VSSI) control charts has not so far been investigated. In this paper, we evaluate the effect of measurement errors on the VSSI control charts. After a model development, the effect of measurement errors and multiple measurements on the performance of VSSI scheme are evaluated in terms of the out-of-control average time to signal (ATS) criterion, which is obtained using a Markov Chain approach. At last, a real case is presented to show the application of the proposed scheme.
    Keywords: Variable sample size, sampling interval (VSSI) control charts, Adaptive control charts, linearly covariate error model, Average time to signal (ATS), Markov Chain approach
  • A. Cheraghalipour, M. M. Paydar, M. Hajiaghaei-Keshteli Pages 1005-1016
    In this paper, a hybrid multi-criteria decision-making (MCDM)-method and mixed integer linear programming (MILP) approach in order to evaluation of the returned product's collectors along with their ordered quantities, is utilized. Firstly, the most important criteria of collection center in the car industry are identified. Then, in order to evaluate these proposed criteria, a hybrid Fuzzy Decision-Making Trial And Evaluation Laboratory (FDEMATEL)- evaluation of mixed qualitative and quantitative data (EVAMIX) approach is applied. By this method, the most important criteria and their weights along with collection center's score are determined. In addition, an MILP mathematical model is proposed for selection of the best collection center and computation of ordering quantities. An efficient approach for collection center selection and a novel application of combined FDEMATEL, EVAMIX, and MILP model can be considered as the main contributions of this paper. It should be noted that, to measure the performance of this method a recycling company as a case study in Iran has considered which of this firm collects effete tire and ball bearings of cars. Implementation of this case study can be considered as the other contributions of this paper. At last, with help of obtained results the proper collection center and their ordered quantities are computed. In addition, for measure efficiency of the proposed model, some numerical example, in various dimensions is considered. Moreover, the managers of this industry with the help of a simple methodology can choose the appropriate suppliers.
    Keywords: Reverse logistics, collection center selection, EVAMIX, Fuzzy DEMATEL, MILP model
  • M. S. Fallahnezhad, T. Jafarinodoushan Owlia, M. H. Abooie Pages 1017-1028
    In this paper, we develop an optimization model for the economic design of repetitive sampling plan in the presence of two markets. The process under consideration produces a product with a normally distributed quality characteristic with unknown mean and known variance. The quality characteristic has a lower specification limit. The quality of the product is controlled via lot-by-lot acceptance sampling plan. The objective function used in the model is maximizing profit and product conformity using the Taguchi loss function as a surrogate for product conformity. Risks of producer and consumer in two different markets are considered as constraints. We demonstrate the application of the model using a numerical example. Sensitivity analysis on model parameters shows that the result of the model is sensitive to changes in model parameters.
    Keywords: Economic Design, Repetitive Sampling Plan, Taguchi Loss Function, Producer Risk, Consumer Risk, Markov Chain, Process Mean
  • M. Fallah, A. Mohajeri, Mohammad Barzegar-Mohammadi Pages 1029-1037
    Global warming created by large scale emissions of Greenhouse Gases (GHG) are a worldwide concern. Due to this, the issue of green gas network has required more attention in the last decades. Here, we address the GHG-based problem that arises in a gas network where gas flow is transferred from the Town Board Station (TBS) to consumers by pipeline systems. Given this environment, an optimization model for a gas network in which GHG emission is expressed in term of environmental constraints is developed. Here, we formulate a gas network considering profitability and ecological goals to achieve sustainable development. To solve the model accurately, in small and medium sizes, we use GAMS 23.2 software and compare their results with the result of a metaheuristic algorithm (Hybrid GA/SA). The results show that the proposed algorithm is able to produce better answers in shorter time for large-scale problems. A case study in Mazandaran Gas Company in Iran is conducted to illustrate the validity and effectiveness of the proposed approach.
    Keywords: Green gas network, Hybrid GA-SA algorithm, Greenhouse gas emission, Sustainable development
  • A. Rahmani-Ahranjani, A. Bozorgi-Amiri, M. Seifbarghy, E. Najafi Pages 1038-1047
    High amounts of waste paper are disposed of every year in Iran posing the health hazard and environmental damages instead of being recovered. Collection, recovery and proper disposal of waste paper without damaging the environment need to design an efficient closed-loop supply chain network. The main objective of this paper is introducing a bi-objective, multi-echelon, multi-product and single-period logistics network design model in the paper industry while taking into the environmental issues. Alternative recovery options such as recycling with technology selection and energy recovery are considered simultaneously in this model. A life cycle assessment method ISO is utilized for quantifying the environmental impact along the closed-loop supply chain. The model is applied to an illustrative case study of the paper industry in East Azerbaijan of Iran and fuzzy goal programming method is used for solving the proposed bi-objective network optimization model. Also, sensitivity analysis of the proposed model is performed designing different scenarios.
    Keywords: Closed-loop supply network design, bi-objective programming, recovery system, paper industry
  • S. Noroozi, S. K. Sadrnezhad Pages 1048-1053
    Stent is a metal mesh tube for opening the obstructed vessels of the body. Ni-Ti alloy is a suitable metal for fabrication of stent due to its potential for applying the appropriate stress and strain to the vessel walls. In this study, super-elastic Nitinol wire was used to build stent samples usable to open femoral vessel. Ageing was performed at 500°C for different periods of time to determine the most appropriate transformation temperatures and shape memory/superelasticity behavior of the sample. Mechanical and structural properties of the alloy were determined by differential scanning calorimetry (DSC), electron probe micro analysis (EPMA) and metallographic studies. Ability to stand vessel wall pressure was studied by crush test. Images of scanning electron microscope (SEM) showed that the surface integrity was not affected by strain. The artificial silicon vessel in Simulated Body Fluid (SBF) at 37°C was used for implanting of the crimped stent. The recovery of strain and exertion of stress to the vessel wall was investigated after removal of the stent from the catheter.
    Keywords: Orthodontic wire, Stent, Superelasticity, Shape memory, Nickel-titanium alloy
  • A. H. Sarabandi, A. Jabari Moghadam Pages 1054-1065
    The steady-state fully-developed laminar flow of non-Newtonian power-law fluids is examined in a circular microchannel with slip boundary condition and under an imposed constant wall heat flux. Effects of slip as well as the hydrodynamic and thermal key parameters on heat transfer and entropy generation are investigated. The results reveal that increasing the Brinkman number and the flow behavior index both lead to increasing the entropy generation and decreasing the Nusselt number. In heating process, the temperature difference between the fluid and the wall decreases as the slip coefficient increases; similar trend may or may not be observed for cooling process, determined by the range of the slip coefficient as well as the Brinkman number. An increase in the slip coefficient leads to an increase in both the Nusselt number and the Bejan number, whereas it gives rise to a decrease in entropy generation. For each particular value of the slip coefficient, the Nusselt number approaches a specific value as the Brinkman number and/or the flow behavior index increases. An increase in the flow behavior index or a decrease in the slip coefficient results in incrementing the average entropy generation.
    Keywords: Heat Transfer, Non-Newtonian fluids, Slip, Brinkman number, Analytic solution, Entropy generation, Nusselt number
  • X. Sun, S. Deng, G. Chen, W. Zhang Pages 1066-1073
    In this paper, an analytical formula to calculate the radial stiffness of groove elastic support is presented. The influence of structure parameters on radial stiffness and homogeneity of radial stiffness is investigated as well. The accuracy and calculating speed of the analysis formula are compared to that of finite element method (FEM). Findings are as following: The calculating speed of analysis formula is more efficient than that of finite element method (FEM). When the number of groove is less than 20, the maximum relative error of two methods is less than 10%. The radial stiffness of groove elastic support increases with the groove number, thickness of arc beam and transition angle, but decreases with the groove gap. The radial stiffness changes slightly and periodically with the azimuth angle of radial load, and the greater groove number and the thinner thickness of arc beam, the more homogeneous radial stiffness of groove elastic support.
    Keywords: groove elastic support, analysis formula, radial stiffness, structure parameter, stiffness homogeneit
  • I. S. N. V. R. Prasanth, D. V. Ravishankar, M. Manzoor Hussain Pages 1074-1080
    Milling of fiber reinforced polymer composites is of great importance for integrated composites with other mating parts. Improper selection of cutting process parameters, excessive cutting forces and other machining conditions would result in rejection of components. Therefore, machining conditions are optimized to reduce the machining forces and damages. This work reports practical experiments in milling, to study the effect of machining conditions on cutting force, surface roughness and damage factor of Glass Fiber Reinforced Polymer (GFRP) composites. The experiments were carried out with a designed carbide end mill tool by a random set of milling process parameters. The results showed that machined surface integrity was highly influenced by the spindle speed followed by the feed rate. The results of the experiments were illustrated and analyzed by interaction plots and Scanning Electron Microscope (SEM) images.
    Keywords: Cutting process parameters, GFRP composite laminates, Hand laid-up compression moulding, Solid carbide end mill tool, Scanning electron microscope (SEM)
  • R. Mehdipour, Z. Baniamerian, M. H. Saidi Pages 1081-1089
    The objective of this paper is to optimize defrost/demist performance in a vehicle. However, to initiate the problem, it is necessary to have a thorough understanding of flow behavior within the compartment. So a full-scale model of passenger compartment has been modeled and the air stream from very near to the windshield up to back of the compartment has been analyzed applying computational fluid dynamics. A computational C code is developed to calculate vapor film thickness glass temperature and some other parameters in different time steps. The code inputs are the air flow parameters resulted from the CFD simulation. Some different flow arrangements are prepared by changing locations of demist panels and outlet pores to evaluate defrost and demist performance. Ultimately, between 6 different cases suggested, the optimum location of demist panels and exit vents is determined. For the case in which warm air enters through left A-Pillar in addition to the bottom panel, and exits through right A-Pillar, the windshield clearance time is minimum for the same initial conditions.
    Keywords: Defrosting, Demisting, Automobile windshield, Heat transfer
  • M. Zunaid, Q. Murtaza, Samsher Pages 1090-1097
    A shower cooling tower (SCT) operates without fill because of salt decomposition on the fill that leads to deterioration of conventional cooling tower performance. This study presents a two-dimensional mathematical model for energy and exergy analysis of multi-diameter droplets and air interaction along with the height of the forced draft SCT, to predict the exit condition of water droplet for industrial application. Different inlet air dry bulb temperatures (DBT) were used for the study and the model was validated with experimental results. At the inlet of the tower, ten different diameters of water droplets simultaneously were used at a given time for analysis and the droplet diameter model based on Rosin Rammler distribution. The result showed that thermal efficiency and second law efficiency relatively increased along the height of SCT with increase of the inlet air temperature. It was confirmed that maximum reduction in water droplet temperature along the height of SCT was achieved by minimum inlet air DBT. It was also noticed that exergy supplied by water was more than exergy absorbed by air and maximum destruction of total exergy took place at the beginning of air-water interaction.
    Keywords: Exergy Analysis, Multi Droplets, Rosin Rammler distribution, Mean Droplet Diameter
  • M. Sai Viswanathan, V. Manoj Kumar Pages 1098-1104
    This paper describes the vision system for a humanoid robot, which includes the mechanism that controls eyeball orientation and blinking process. Along with the mechanism designed, the orientation of the camera, integrated with controlling servomotors. This vision system is a bio-mimic, which is designed to match the size of human eye. This prototype runs face recognition and identifies, matches with a face in the database. Recognition of face leads to capture the facial image and synchronize with the face. As the individual shows any motion, the system also moves according to it.
    Keywords: Bio-mimic, Blinking, Camera-orienting device, Face recognition using LBPH, Classifier
  • S. S. Tabatabaee Moradi, N. Ivanovich Nikolaev Pages 1105-1109
    Unsuccessful cementing operation can jeopardize the whole well construction process, resulting in further costly and time consuming repair operations. The quality of cementing job is dependent on the cement composition and its properties. Design of cement composition is based on the available geological condition, materials and technical situation at well location. The cement properties like flow-ability and strength properties are tested by laboratory methods before application in field conditions. Study of the slurry sedimentation stability is of great importance especially for construction of directional or horizontal wells. There is no convenient direct method to investigate the sedimentation stability of the cements. In this paper, a laboratory method is presented to assess the stability of the slurry by measuring its free fluid content. Laboratory investigations are expanded to study the effect of different additives (weighting agent, silica sand, silica flour and magnesium oxide) and well inclination angle on the sedimentation stability of the slurries. Results show that additive specific surface area plays a significant role in the stability of the cements and therefore should be measured for every additive precisely.
    Keywords: Well construction, Cement, Sedimentation processes, Specific surface area