فهرست مطالب

Engineering - Volume:35 Issue: 9, Sep 2022
  • Volume:35 Issue: 9, Sep 2022
  • TRANSACTIONS C: Aspects
  • تاریخ انتشار: 1401/03/17
  • تعداد عناوین: 10
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  • Seyed Mahdi Jameii *, Kourosh Khanzadi Page 1

    Unlike traditional gaming where a game run locally on a user's device, in cloud gaming, an online video game runs on remote servers and streams directly to a user's device. This caused players to become independent of having high hardware resources in their local computers. Since video games are a kind of latency-sensitive application, cloud servers far from users are not suitable. In fog computing, fog nodes are in the vicinity of users and can reduce the latency. In this paper, a latency reduction method based on reinforcement learning is proposed to determine which computing fog node can run the video games with the lowest latency. In the proposed method, a Principal Component Analysis (PCA) based approach is used to extract the most important features of each video game as the input of the learning process. The proposed method was implemented using Python. Experimental results show that the proposed method compared to some existing methods can reduce the frame latency and increase the frame rate of video games.

    Keywords: Reinforcement Learning, Cloud-fog gaming, Principal component analysis, Latency Frame rate
  • Haider Al-Jelawy *, Alaa Naji, Alaa Hassoon, Ayad Al-Rumaithi Page 2

    Concrete filled steel tube (CFST) columns are being popular in civil engineering due to their superior structural characteristics. This paper investigates enhancement in axial behavior of CFST columns by adding steel fibers to plain concrete that infill steel tubes. Four specimens were prepared: two square columns (100*100 mm) and two circular columns (100 mm in diameter). All columns are 60 cm in length. Plain concrete mix and concrete reinforced with steel fibers were used to infill steel tube columns. Ultimate axial load capacity, ductility and failure mode are discussed in this study. The results showed that the ultimate axial load capacity of CFST columns reinforced with steel fibers increased by 28% and 20 % for circular and square columns, respectively. Also, the circular CFST columns exhibited better ductility than the square CFST columns due to better concrete confinement. Circular and square CFST columns with steel fibers showed improved ductility by 16.3% and 12%, respectively. The failure mode of the square CFST columns were local buckling which occurred near the end of columns, while, for the circular CFST columns, local buckling occurred near the mid-height. Also, the study involved sectional analysis that captured the behavior of CFST columns very well. The sectional analysis showed that increasing steel fiber content to 2% increased the axial load capacity by 51% and 38% for circular and square CFST columns, respectively. Furthermore, sectional analysis showed that doubling section size increased axial load capacity by approximately 4 and 5 times for circular and square columns, respectively.

    Keywords: Concrete, Steel Tube, Composite elements, Steel Fibers, Ductility, Columns
  • Tuswan Tuswan *, Eli Sari, Abdi Ismail, Aditya Prabowo Page 3

    Research on lightweight material on ship structure has taken giant steps during the last decade. One reason is that shipping activities have increased and, therefore, the possibility of increasing the carrying cargo capacity in a realistic way using advanced lightweight material. This article summarizes a research investigation regarding the experimental tests of vinyl ester bio resin material using palm oil and sesame oil based on Lloyd's Register (LR) standard. Several tests are conducted, including density, water absorption test, Fourier transformed infrared test (FTIR), scanning electron microscope (SEM), and mechanical tests to evaluate the effect of 2-10% addition of vegetable oils on mechanical properties. The influence of the addition of vegetable oils is successfully characterized using physical measurements, which indicate the possible formation of a polymer blend to increase in elongation value. Mechanical testing shows that adding vegetable oils causes a decrease in average density, hardness, bending strength, and tensile strength. The bending strength decreases about 9.20 – 47.06% for 2-10% palm oil addition and 5.33 – 42.40% for sesame oil addition. Moreover, vegetable oil causes a tensile strength decrease of about 5-18.75% on palm oil and 3.75-13.75% on sesame oil. As summarized, bio resin based on sesame oil has better mechanical behavior with the oil addition of 4-8% fulfills all Lloyd’s Register criteria.

    Keywords: Bioresin, Palm oil, Sesame oil, Core Sandwich, Ship Structure
  • KEYURKUMAR TANDEL *, Jyoti Menghani Page 4

    Tungsten Inert Gas Welding (TIG) is the most preferred joining process for aluminum alloys, but it produces weld joint having inferior mechanical property in comparison with base metal because of inherent limitations of the process. To improve the mechanical properties, the weld is post processed by friction stir processing (FSP) upto depth of 2mm. This paper presents the effect of performing FSP on autogenous TIG welded butt joint of Al-5083, 6mm thick plate. Mechanical and metallurgical properties of both processed and unprocessed autogenous TIG weld are compared. Characterisation techniques adopted to evaluate weld joint are tensile test, microhardness measurement, microstructural examinations and SEM analysis. Tensile strength of autogenous TIG weld joint is lowered by 6.5% compared to base metal because of presence of micro porosities in the weld metal. Friction stir processing produces the fine grain refined structure, marginally improves the tensile strength of the autogenous TIG weld joint by 2.7%. Microhardness of the autogenous TIG weld metal of the surface is raised from 163.6 HV to 298 HV after performing FSP. However, SEM images of fractured surface of friction stir processed specimen reveals fine dimpled structure which indicates that ductility of the weld joint remain unaffected after performing FSP on autogenous TIG weld joint.

    Keywords: Friction Stir Processing, Surface modification, Autogenous TIG welding, Grain refinement
  • Masoud Mahmoodi *, Hadi Tagimalek, MohamaadReza Maraki, Saeed Karimi Page 5

    As one of the methods of Severe Plastic Deformation (SPD), the Accumulative Roll-Bonding (ARB) process leads to the production of high-strength metal sheets and fine-grained structures. In this paper, the Single Point Incremental Forming (SPIF) of Al 1050 sheets, processed by the ARB and CARB (Cross-Accumulative Roll-Bonding), is experimentally and numerically investigated. The forming force, thickness distribution, and forming depth in both cases (ARB and CARB) are all determined in this research. The result shows that the formability of CARB samples is higher than ARB samples. Furthermore, the formability of both ARB and Al 1050 annealed samples are equal in the initial pass. In addition, the samples’ strain is enhanced by increasing the number of rolling passes, and as a result, the formability scales down. The results obtained using the dynamometer reveals that the vertical forming force extent in the CARB samples is higher than in the rest of the samples.

    Keywords: Single Point Incremental Forming, accumulative roll-bonding, Cross accumulative roll-bonding, Thickness Distribution, Formability, force
  • Bhairav Thakur * Page 6

    This state-of-the-art review study emphasized the problem of failure of Nuclear Power Plants (NPP) due to earthquake forces. Soil-NPP interaction may lead to damage to these unique structures of the critical infrastructural system of any nation in demand to fulfill the energy requirement. So, the soil-structure interaction (SSI) is the key motivating factor to review the fundamentals of NPP with its base soil conditions. Moreover, the problems associated with NPP-SSI have been overcome with the application of an advanced foundation system called combined pile raft foundation (CPRF). This study checks the scope of the provision of CPRF to NPP through SSI. The approaches for analyzing the seismic behavior of NPP in CPRF are strategically reviewed in this study. According to the literature findings, SSI is the most significant factor in deciding the seismic resistance of NPP. The fragility analysis demonstrated the importance of SSI in the design of NPP earthquake behavior. CPRF plays an important role in NPP-SSI to minimize structural damage.

    Keywords: Combined Pile Raft Foundation, Failure, Fragility, nuclear power plant, Seismic Resistance, Soil Structure Interaction
  • Mostafa Rahimnejad *, Fateme Ghorbani, Abas Ramiar Page 7

    A simple, inexpensive, reliable, portable, and environmentally friendly colorimetric method was developed to determine DA concentrations, In this research, colorimetric detection of dopamine (DA) was proposed on fast, simple, sensitive and low-cost μPADs, which is fabricated by using laser cutting technique. For this purpose, a Whatman® Filter paper No.1 was used as an analytical substrate. In paper-based microfluidic systems, wax printing is commonly used to create a hydrophobic barrier, but in this study, labels were used for the first time to create hydrophobic barriers due to their cost-effectiveness and easy access. The presence of DA made the red color bolder, and quantitative amount was obtained by taking picture from the colored areas with a smartphone and using Photoshop software. This method demonstrates the potential for detection without equipment because the chemical reaction can only be seen on paper with naked eyes. The analytical platform is made of cellulosic material that is compatible with many chemicals, and it is easy to use and can be easily stored

    Keywords: Microfluidic Systems, Dopamine, Colorimetric detection, μ PADs, smartphone, Oxidation-Reduction
  • Gaurav Dhadse *, Gangadhar Ramtekkar, Govardhan Bhatt Page 8

    The hyperbolic non-linear elastic constitutive model for idealization of non-cohesive soil has been commonly used by researchers in numerical modeling. The hyperbolic model includes parameters (HMP) such as modulus number ‘K’, exponent ‘n’, angle of internal friction ‘φ’ and failure ratio ‘Rf’, which are evaluated using laboratory shear test. The parameters ‘K’, ‘n’ and ‘Rf’ are evaluated from transformed stress-strain curve whereas ‘φ’ is directly evaluated from normal and shear stress. When the samples are in large numbers, the process becomes very tedious and there will be no correlation for evaluation of such parameters. These parameters are highly dependent on particle size, moisture content and density. In this paper, box shear test has been performed on coarse, medium and fine sand as well as on fine gravels with varying densities. The tests have been conducted in dry and moist conditions. Based on the experiments performed, the HMP have been evaluated. The correlations have been established for every parameter based on particle size, moisture content and density. These correlations will be useful in direct evaluation of model parameters.

    Keywords: Hyperbolic Model Parameters, Numerical modeling, Box Shear Test, particle size, Non-cohesive Soil
  • Mohammad Gholami *, Zarei Sanaz Page 9

    Quantum-dot Cellular Automata (QCA) is one of the new nanoscale technologies which proposed for future circuits. This technology has been remarkable due to its faster speed, lower size and reduction in power consumption compared to CMOS technology. Many circuits have been implemented in this technology including shift registers, they are one of the most important digital circuits for many applications. With the development of QCA technology, it is important to provide testing methods for testing these circuits.4-Bit serial shift registers designed in previous research were not capable of testing their output. In this paper, MUXED-D scan cell concept helps to detect the errors before fabrication and reduce time and cost. The MUXED-D scan consists of a D flip-flop and a 2to1 multiplexer. Compared to the latest scan cell, we have seen a 25 % decrease in occupied area and 15.62 % decrease in the number of cells and latency from 1 to 0.75 clock cycle. In general, this scan cell circuit is made of 27 cells with an area of 0.03 µm2 and a latency of 3 clock cycles. The proposed shift register includes four scan cells with two inputs which includes main and test signals. In fact, the number of cells used for the last 4-bit serial testable shift register in this design is 324, 0.39µm2 occupied area and the corresponding delay is 6.75 clock cycles. In order to verify this performance, QCA simulator is used

    Keywords: MUXED-D scan cell, Nanotechnology, Quantum-dot Cellular Automata, Shift register
  • O. M. Makki, H. M. K. Al-Mutairee Pages 1744-1751

    In most civil constrictions, concrete members need to gain some ductility to resist the dynamic loads which it suffered. For sustainability and economical reasons, scrapped tires rubbers are the most cheap material able to achieves this goal. The bad manner in such replacement is that, the high replacing percentages cause a large drop in concrete mechanical properties till becomes unstructural. This paper offers six structural rubcrete mixes and discuss its properties after replacement. Slump, density, water absorption, compressive strength for cubes and cylinders, impact resistance, flexural strength, splitting, ultrasonic and stress versus strain curves were tested and discussed. It can be concluded that, the sustainable rubcrete mixes still structural in spite of the dropping in strength due to the replacing process. Concrete tensile, compressive and flexural strength minimized for every incrementing in rubber amounts due to the loss of bond between mortar and the rubbers.

    Keywords: Rubberized Concrete, Sustainable Concrete, Rubcerte, Green Concrete, Structural Rubcrete