فهرست مطالب

  • Volume:32 Issue:6, 2019
  • تاریخ انتشار: 1398/03/11
  • تعداد عناوین: 14
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  • E Arunraj *, S. Vincent Sam Jebadurai, C. Daniel, J. Joel Shelton, G. Hemalatha Pages 799-804
    Despite the use of modern materials, clay bricks are reasonably preferable materials nowadays. However, the moo fetched and flexibility of clay bricks are not related with tall natural and feasible values, particularly with regard to crude fabric sources and fabricating processes. Agricultural world is growing fast, with increased rural arrive development and land cultivation leading to massive development of the agro-based industry leading to expansive amount of agrarian squanders which are not recycled. Therefore, these wastes can be reused by reviving fibres obtained from disposed leaves and fruit bunches, which can be used in brick-making. This research investigated the mechanical properties of clay bricks built by including two naturally existing fibres to a clay-water blend, in heated and non-heated conditions. The fibre samples were sourced from pineapple leaves (PF), Coconut at the range of 0.5-1.5 % with length 5mm and 10mm. To that mixture, cement was mixed at 5 %, as it is a binder. It was observed that the two fibres had distinct after effects on the bricks produced and the presence of cement dominated the compressive strength. The non-baked bricks disintegrated when immersed in water and the baked ones exhibited cement-dependent qualities in water-absorption and density variations. Interestingly increase in fibre content did not cause significant density reduction in both the baked and non-baked bricks.
    Keywords: Baked Brick, Non-Baked Brick, Coir Fibre, Sisal Bibre, Compressive strength
  • G. Shafabakhsh *, S. Ahmadi Pages 805-812
    Weak bonding between layers of pavement leads to damages on the composite pavement. Bonding plays an important role in the durability and maintenance of composite pavement layers. The present study evaluates the factors effective in bond strength of the interface between concrete and asphalt pavements. The factors considered for this purpose include steel slag percentage in the concrete pavement, different types of modified bitumen, and rates of tack-coat. To measure the bond properties, direct shear and shear fatigue tests were carried out. In addition, texture depth and abrasion resistance were used in accordance with EN 1338 standard to measure the roughness properties of concrete pavement. The test results showed that 50% replacement of  steel slag with aggregate resulted in an increase in physical properties and texture depth of concrete pavement. Moreover, the results of the shear strength test of composite pavement revealed that the optimal rate of using tack-coat varies between 0.6 and 0.9 l/m2 and depends on the type of tack-coat. Finally, a higher shear strength was obtained for crumb rubber bitumen containing hydrated lime compared to crumb rubber modified bitumen and control bitumen.
    Keywords: Composite pavement, Shear strength, Mechanical Properties of Concrete, steel slag, Tack coat
  • P. Narasimha Reddy *, J. Ahmed Naqash Pages 813-819
    In the modern era, many research works are being carried out throughout the world for finding out a suitable cementitious material for the replacement of cement. The supplementary cementitious materials (SCM) can be used as a replacement of cement in the construction industry to minimize the carbon dioxide emission which is implicated in global warming and climatic changes in the environment. This paper presents the mechanical and durability index properties for M30 grade normal concrete (NM) and green concrete (GC). From the experimental results, it was clearly observed that the use of alccofine has resulted in attainment of higher strengths at early ages in concrete. Green concrete mix with 20% alccofine replacement of cement has achieved higher mechanical and durability index properties as compared to all other mixes. Response surface methodology was adopted to optimize the experimental data set in which regression equation was developed by relating response variable to input variable. This method helped to predict the experimental values within an acceptable error range. The predicted values were cross validated by employing coefficient of determination (R2) and residual sum of squares (RSS) which showed a good fit.
    Keywords: Alccofine, Mechanical properties, water absorption, response surface method
  • S. S. Pastor, C. T. Rivera, O. F. Avilés *, M. F. Mauledoux Pages 820-827
    This paper puts forward a real-time angular tracking (motion capture) system for a low cost upper limb exosuit based on sensor fusion; which is integrated by an elastic sleeve-mitten, two inertial measurement units (IMU), two flex sensors and a wireless communication system. The device can accurately detect the angular position of the shoulder (flexion-extension, abduction-adduction and internal-external rotation), elbow (flexion-extension and forearm supination-pronation), and wrist (flexion-extension) joints. In addition, the state of the hand (opened-closed). Finaly a PID controller is applied to the exosuit in order to replicate the movements performed by the arm into a 6 DOF robot arm.
    Keywords: Motion Tracking, Wearable Sensors, Upper Limb Exosuit
  • N. Torabi, R. Tavakkoli, Moghaddam *, E. Najafi, . Hosseinzadeh, Lotfi Pages 828-834
    This paper presented a new two-stage green supply chain network, in which includes two innovations. Firstly, it presents a new multi-objective model for a two-stage green supply chain problem that considers the amount of shortage in the network, reworking, and carbon-trading cost produced in the green supply chain. Secondly, because of the complexity of this model, it uses a new multi-objective interior search algorithm (MOISA) to solve the presented model. The obtained results of the proposed algorithm were compared with the results of other multi-objective meta-heuristics, namely MOPSO, SPEA2, and NSGA-II. The outcomes demonstrate that the proposed MOISA gives better Pareto solutions and indicates the superiority of the proposed algorithm in most cases. This paper presented a new two-stage green supply chain network, in which includes two innovations. Firstly, it presents a new multi-objective model for a two-stage green supply chain problem that considers the amount of shortage in the network, reworking, and carbon-trading cost produced in the green supply chain. Secondly, because of the complexity of this model, it uses a new multi-objective interior search algorithm (MOISA) to solve the presented model. The obtained results of the proposed algorithm were compared with the results of other multi-objective meta-heuristics, namely MOPSO, SPEA2, and NSGA-II. The outcomes demonstrate that the proposed MOISA gives better Pareto solutions and indicates the superiority of the proposed algorithm in most cases.
    Keywords: Green Supply Chain Network, Multi-Objective Optimization, Carbon Price, Interior search algorithm, meta-heuristic algorithm
  • M. Rabbani *, E. Talebi Pages 835-841
    One of the most important issues in area of health and hygiene is location-allocation of organ harvesting centers and transplant centers according to coordination between supply and demand. In this paper, a mathematical model is presented for location-allocation of organ harvesting centers and transplant centers. The proposed model does not only minimize the present value of the total system costs, but also minimizes the geographical inequalities. The presented model is a bi-objective nonlinear mathematical programming and some of the problem parameters, such as cost, transport time and the like are associated with uncertainty and considered as fuzzy sets in the mathematical formulation. In this paper, an Organ Transplant Supply Chain (OTSC) has been designed and the ε-constraint method has been used to solve the problem and Iran is considered as a case study. The results show that the patient's family satisfaction rate is more important than the viability rate in the number of transplant operations performed and for a transplant operation to be performed, the minimum satisfaction rate (Bh) should be 0.4 and organ viability rate (UD0) should be 0.2.
    Keywords: location-allocation, Organ Transplant, Organ Harvesting, Supply chain, Uncertainty, ?-constraint method
  • S.K. Sadrnezhaad *, M. Parsafar, Y. Rashtiani, M. Jadidi Pages 842-851
    Scoliosis, kyphosis, and bone fracture are health problems, especially of the elderly throughout the world. The vertebra protects the spinal cord. Any impairment to the vertebra can lead to pain and nervousness. Ni-Ti alloy (Nitinol) helps to resolve the problem by fulfilling such requirements as for strength, durability, resistance to wear, and shockwave damping which is due to the shape memory effect. Nitinol medical applications have so far been restricted to surgical devices and orthopaedics. Little has been said about Nitinol use for medication of the spinal vertebra disorder. This article appraises the potential features of Nitinol for vertebral implantation and therapeutic prescription consistent with the specific anatomical variation. Staples, screws, cages, stents, and posterior-stabilizers made of Nitinol have passed in-vitro tests and in some cases in-vivo examinations. Using anatomically tailored Nitinol for treatment and administration of the damaged vertebra is proposed as a forecastable dream.
    Keywords: Spinal, Vertebrae, Nitinol, Shape memory, Superelasticity, Implantation
  • F. A. Hesari *, M. Moradi, F. S. Torknik Pages 852-859
    Size, shape, volume fraction and distribution of embedded g/ phase in g phase has direct effect on strength of INCONEL alloy. Microstructure parameters of INCONEL phases are quantified from microstructure images using transmission electron microscopy (TEM). Different TEM sample preparation techniques were used to study INCONEL 738 alloy microstructure for transmission electron microscopy (TEM). The INCONEL 738 was first cut into a 1 × 1 cm slice with 600 µm thickness with diamond wire cut. INCONEL sample was mounted by wax (M135), after initial grinding and polishing. The molded INCONEL sample was further polished by different grit size SiC paper to reduce the thickness below 80 micron. At this stage, 3 mm discs were cut from the thin slice of INCONEL alloy by mechanical punch machine. The 3 mm discs of INCONEL alloy were used for TEM sample preparation. Three methods of electro-jet polishing, ion milling and micro control dimpling were employed to prepare transparent TEM sample to observe the surface microstructure details of INCONEL 738 alloy. Electro-jet polishing TEM sample preparation technique could reveal microstructure details of INCONEL alloy g and g/ phases using 42% H3PO4, 34% H2SO4, 24% H2O electrolyte at about – 400C bath temperature and applied voltage of 30 V.
    Keywords: INCONEL Alloy, Jet Electro-polishing, Ion Beam Milling, Micro Control Dimpling
  • M. M. Goli Bidgoli, A. Ranjbaran, K. Mirzavand, Y. Shajari, Z. S. Seyedraoufi *, M. Porhonar Pages 860-865
    Application of thermoplastic materials has increased dramatically in recent decades due to its recyclability, low density, resistance to chemical changes. The friction stir welding process is one of the new methods of solid state welding, which has recently undergone a significant improvement. In this research, using a new tool Made of plain carbon steel st37 in friction stir welding and low cost turning machine, composite sheets of thermoplastic polymer base have 12% continuous carbon fiber in the form of buttocks with two rotational speeds of 250 and 355 rpm and two advance speeds of 5/6 and 9 mm/min Optical microscope images (OM) showed the complete connection of materials. Increasing the inlet temperature resulted in the formation and growth of cavities and converting them into tunnel cavities. In general, the parameters affecting the connection quality in this study included the main shoulder diameter and rotational speed, so that, based on the results of scanning electron microscopy (SEM), the increase in rotational speed resulted in the grinding of continuous carbon fibers and thus increased tensile strength. The results of the tensile test showed that the failure of the samples is due to microstructural changes in the HAZ, in the joint zone of the welding zone and the base materials. According to the results, it can be said that using this new tool in the friction stir welding method, because of the reduction of rotational speed compared to previous studies and the lack of use of a multi-axial milling machine, can save energy.
    Keywords: polymer composite, carbon fiber, Friction Stir Welding, New Tools, tensile strength
  • M. H. Shojaeefard, A. Khalkhali *, S. O. Shahbaz Pages 866-871
    Surface roughness (SR) has an adverse effect on the appearance of low-carbon steel parts, formed in the asymmetric incremental sheet forming (AISF) process, particularly those requiring painting operation. The purpose of this study is to investigate the effects of AISF process parameters on the surface roughness of an asymmetric part formed on low-carbon steel sheets. The parameters are feed rate, tool diameter, vertical step and spindle speed. Taguchi design of experiment (DOE) is used to investigate the process parameters effects and their interactions to achieve the minimum surface roughness. According to the obtained results, the roughness on the surface of low-carbon steel sheets is decreased during the asymmetric single-point incremental forming (ASPIF) due to a decrease in the vertical step and an increase in the tool diameter. In addition, the tool rotational speed and the feed rate have low effects on the surface roughness. The carried out validation test demonstrates that the Taguchi technique can effectively optimize the level of each input factor to ensure the best surface quality.
    Keywords: Asymmetric Single-Point Incremental Forming, Low-Carbon Steel Sheet, Surface roughness, Taguchi technique
  • E. Poursaeidi *, K. Torkashvand, M. Mohammadi Pages 872-876
    An experimental investigation was conducted to find the effect of spraying method of coating of Thermal Barrier Coatings (TBCs) on their oxidation behaviour and resistance to various thermal loading. Isothermal and thermal shock tests were performed in order to study oxidation behaviour of air plasma sprayed Bond Coat (BC) and assess its effect on TBCs lifetime under the stated loadings. Specimens, after loading were investigated using Field Emission Scanning Electron Microscopy (FE-SEM). Results showed in spite of forming various oxide layers within the BC its oxidation in Bond Coat/Top Coat interface behave the same as samples coated by other methods and no failure was observed at substrate/BC interface or within the BC.
    Keywords: Thermal barrier coating, Air plasma sprayed, oxidation, Failure
  • F. Wang, L. Fang * Pages 877-883
    In the fault diagnosis of automaton, the vibration signal presents non-stationary and non-periodic, which make it difficult to extract the fault features. To solve this problem, an automaton fault diagnosis method based on morphological component analysis (MCA) and ensemble empirical mode decomposition (EEMD) was proposed. Based on the advantages of the morphological component analysis method in the signal separation, using the morphological difference of the components in the automatic vibration signal, different sparse dictionaries were constructed to separate the components, eliminates the noise components and extracted the effective fault characteristic component, the extracted impact components are decomposed by EEMD and the energy feature of each IMF component is calculated as the fault features, then put the fault features into SVM (Support Vector Machine) and identify the faults. Through the construction simulation example and the typical fault simulation test of automatic machine, it showed that the morphological component analysis method had better noise reduction and signal separation effect. Compared with the traditional EEMD method, the feature extraction method based on the MCA-EEMD can distinguish automaton fault types more effectively.
    Keywords: Automaton, Fault Diagnosis, Vibration Signal, Morphological Component Analysis, Ensemble Empirical Mode Decomposition
  • M. R. Assari *, H. Basirat Tabrizi, M. Parvar, M. Forooghi Nia Pages 884-892
    In this research, a rotating solar still that uses external bottom reflectors was experimentally investigated. The solar still and reflectors have the capability to shift their angle with respect to the south and the reflectors have the capability to shift their angle with respect to the horizon. The experiment has been performed in both fixed and rotating states. For the fixed state the solar still was placed toward south and the reflectors were set in such a way to reflect sun rays on the bottom surface of the basin at solar noon. For rotating state, the solar still and reflectors were set manually every half an hour in such a way to reflect sun rays on the bottom surface of the basin and the system was directed toward the sun  all the time. The experiments were performed from November to December for 27 days. Sunny days results indicated that on average, distilled water gained using rotating mode was about 64% more than  the fixed mode. Both the rotating and fixed mode yield for two cloudy days with respect to the average yield of sunny days decreased by 47 and 53%, respectively.
    Keywords: Solar still, External Reflectors, Solar energy, Angle Shifting, Desalination
  • H. Raeissi Jelodar, G. R. Salehi *, R. Abedini Pages 893-900
    In this research, solar-drived integrated Hydrogen production (HP) using high-temperature steam electrolysis (HTSE) is thermodynamically evaluated. This system includes an organic Rankine cycle (ORC), Rankine cycle, Brayton cycle, solar tower, and High Temperature Steam Electrolysis (HTSE). Solar energy supplies thermal energy. This heat source is applied for generating power. This energy is used for HTSE due to its demand in the form of electricity. First, we calculated inlet and outlet energy and their rates for whole subsystems. The results showed 50.77% overall and 31.63% exergy efficiencies related to power generation section and 92.85% overall energy and 91% exergy efficiencies related to hydrogen production section. Also in this research we found the importance of auxiliary equipment. Auxiliary equipment helps that significant amount of hydrogen production to be saved. This amount at 577 K is equal that produces 0.093 kg H2/s
    Keywords: Solar Driven Integrated System, Hydrogen production, High-temperature Steam Electrolysis, Thermodynamic Analysis Energy