ARPN Journal of Engineering and Applied Sciences              ISSN 1819-6608 (Online)
 

 
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ARPN Journal of Engineering and Applied Sciences                     November 2018  |  Vol. 13  No. 21
   
Title: Design mathematical model for heat transfer in laser beam welding process
Author (s): Rafel Hekmat Hameed and Isam Mejbel Abed
Abstract:

The model of energy transport is designed to include the fusion effects by using a moving boundary problem. This model allows accounting for both high order temperature gradients and non-equilibrium state, this leads to more realistic determination of temperature distribution within the work-piece. The model has been employed to simulate the evolution of spatial temperature distribution within the target materials when irradiated with both CW and pulsed laser. This model is explains the welding process in terms of the velocity of fusion surface (V*) which has been calculated as a function of power intensity. The dimension of fusion zone, and heat affected zone are illustrated of target metal with phase transformation under incident power intensity in range of 105 W/cm2. A new scheme of welding mechanism has been implemented. This scheme is based on switching from the transient model of welding to continuous welding (steady state), using lagging method in explicit technique. This method gives more stable solution through a computer program, which calculates the temperature distribution from a moving work-piece.

   

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Title: Identification of soil characteristics on North Toraja landslide, Indonesia
Author (s): Asmita Ahmad, Rosa M. Poch, Christianto Lopulisa, A. M. Imran and Sumbangan Baja
Abstract:

Soil characteristics, being soil the outer part of the lithosphere, greatly affect the occurrence of landslides, but there is still a little research explaining how they interact in order to trigger a landslide. This research aims to identification the soil characteristic that causing landslides in Bengkelekila Sub-District, North Toraja District in South Sulawesi, Indonesia. Ten undisturbed samples (for physical and micro morphological analyses) and eight for soil texture were collected. The measured soil physical parameters were bulk density, particle density and soil permeability. Results show that the porosity and permeability below 30 cm tend to be lower, which cause water saturation of the topsoil after heavy rains and therefore favors the occurrence of landslides. Soil micro morphology showed sub horizontal planar voids, high mineral weathering and striated b-fabrics resulting from swelling-shrinking phenomena, and clay coatings in pores in the subsurface horizons, reducing hydraulic conductivity and triggering landslides.

   

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Title: Effect of blending speed and blade level on the properties of reclaimed rubber modified bitumen
Author (s): Sady Abd Tayh and Rana Amir Yousif
Abstract:

The modification of asphalt binder using crumb rubber has been verified to be extremely successful. Due to the increasing utilization of crumb rubber modifier in asphalt mixtures, there's more attitude to investigate their rheological and physical properties comprehensively. Generally the performance of rubberized asphalt binder are affected by the crumb rubber content and blending conditions. In this research, the examination was done in the laboratory on crumb rubber modified bitumen characteristics after changing three mixing speeds (250,750, and 1250 RPM) and three blade levels (low, mid, and high) using one rubber content (10% by weight of the base bitumen). The rubberized bitumen was characterized in terms of viscosity and resistance for rutting at high service temperatures. The outcomes show that the blade level had no considerable impact on the properties of the modified binder, while the shearing rate was of great effect.

   

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Title: Investigation the effect of flap design optimization on wake propagation behind wings of transport plan
Author (s): Ali Sabri Abbas, Ahmed F. Khudheyer and Jassim Mohammed Hussain
Abstract:

Present paper study aerofoil with NACA2412 with Fowler and Single Slotted flaps that were used for the purpose of numerical investigation the effect of energy adder on the trace of wake behind the proposed wing at a Reynolds number of (2x105) with multi-element flap geometry having different gap, overlap distances, and different flap deflection angle (a). This all were inspected with various angle of attack (AOA) for both types of flaps. Such as [gap = (4.3% c) &(5.3% c)] for single slotted flap, and [(overlap= -5% c with gap =1.25% c) & (overlap= 5% c with gap= 3.75% c) ]. Flap deflection is varied in the range of [20o, 35 o45 o] and the angle of attack in the range of (AOA) is [-5 o, 5 o, 10 o, 15 o]. The numerical study involves simulation to the flow behavior by using ANSYS FLUENT 15.0, the governing equation were solved in three dimensions turbulent regime with appropriate turbulent model (k - ω, SST). Using airfoil of NACA2412 for the wing section, to study the formation of wake turbulence downstream of the trailing edge under the effect of varying different variables related to the geometry of flap position relative to the wing since they form together a multi element airfoil. Present study conducted the effect of dynamic pressure, static pressure, and the kinetic energy in addition to the velocity vector and magnitude in both (x) and (y) directions. Results show that for a gap distance equal to (5.3 % c) it is not recommended to work with both higher flap deflection and angle of attack for single slotted flaps which can be used in multi-element airfoil .And the best positions of single slotted flaps are not so well defined. Hence maximum lift coefficients of single slotted flaps are very sensitive to flap position, however, and optimum configurations cannot be predicted with any degree of accuracy. For a Fowler flap it's convenient to use the combination for an angle of attack equal to (15°) with deflection angle equal to (35° and 45°). Also it was concluded for Fowler flap that as the flap deflection angle increase to a value of (45°) with the existence of an angle of attack equal to (5°) it is clearly revealed the improper combination of these two angles due to large wake vortex generated downstream of multi-element airfoil since the boundary layer that pass over main part of the airfoil.

   

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Title: Experimental study on Coir blended concrete strengthened with Fly-ash and Granite powder
Author (s): Md. Ehraz Akhtar and S. Elavenil
Abstract:

This paper describes the experimental studies on the use of Coir as an enhancement of concrete, Fly-ash and Granite powder as a partial replacement of cement and fine aggregate. The addition of Coir significantly improved the engineering properties of concrete, the application of Fly-ash is to enhance the workable performance of the concrete and the application of Granite powder increases the mechanical strength of the concrete. The definitive goal of this research paper is to focus on the environmental sustainability and to find an alternative to normal control concrete. Concrete mix design of M40 was prepared based on Indian standard code (IS 10262). In the concrete mix, the cement was partially replaced with fly-ash (10%, 20%, 30%, 40% and 50%) by weight fraction along with partially replacement of fine aggregate with granite powder (25% and 50%) by weight fraction and incorporation of 1% coir fibre by volume fraction. Concrete cubes, cylinders and beams were casted and tested for attaining mechanical and physical properties for 7 and 28 days of curing. Non-destructive tests have proved the concrete to be a perfect alternate to control concrete. Mechanical test like compressive strength showed varying results but notable values were seen during the flexural and tensile strength test. Thus, it was accepted that fly-ash and granite powder can be proven perfect replacement for cement and sand along which coconut coir fibre increases the flexural and tensile strength while having varying effect on the compressive strength.

   

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Title: Failure mode and effect analysis (FMEA) applied for risk assessment of fuel oil system on Diesel engine of fishing vessel
Author (s): Rahmad Surya Hadi S., Yuniar Endri Priharanto and Muhamad Zaki Latief
Abstract:

The existence of diesel engine commonly used as a main propulsion engine on fishing vessel, Diesel engine works continuously during fishing operation thus requisite extra intention to ensure the Diesel engine work properly. Since the diesel engine work hardly several components could be failed to work or even worst, for example fuel system. To prevent operational failure of Diesel engine caused by failure of fuel system hence proper maintenance is needed specially on components that exist in fuel system. On the fuel system consists of many components, but only on critical components that need to be treated. To determine the critical component it is necessary to analyze based on the possible failures of each component. This paper aims to apply the FMEA approach to find out how to assess the possible risks in the diesel engine fuel system used as the main propulsion of fishing vessel. The study was performed critical components of the fuel system in the event of failure will result in the failure of the diesel engine operation as follow Fuel storage tanks, transfer pumps, daily fuel tanks, separators, hand pumps, double stage filters, high pressure fuel pumps, high pressure fuel line and injector.

   

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Title: Receptacle - artificial bee colony (R–ABC) classifier for classification of gestational diabetes
Author (s): S. Kavipriya and T. Deepa
Abstract:

Limiting the feature subset size and expanding the classification accuracy for performing the prediction of heart disease among gestational diabetes patients in the dataset is one among the thrust research area in the field of healthcare informatics and its related application domains. In this research work a receptacle artificial bee colony (R-ABC) classifier is employed for performing the aimed task. Certain enhancements are made with the conventional ABC algorithm in terms of using negligible free vitality, swarming separation task conspire, two - point crossover operation and two - way mutation operation are performed. Quick non-commanded arranging are arbitrarily decided for every present solution in the utilized honey bee stage. Between the present solution and its neighbourhood solution and specifically the proposed solution generator is connected to shape another solution set. With the help of edge esteem the classification is performed. Performance metrics such as sensitivity, specificity, true positive rate, false positive rate, precision, accuracy and time taken for feature selection are taken into account. The results are demonstrated with better performance.

   

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Title: New statistical steganography method to hide information in image with high robustness against JPEG attack
Author (s): Mohammed Kamal and Hameed M. Abduljabbar
Abstract:

New statistical steganography method (NSSM) to override or reduce the effect of JEPG attack on a cover image is presented in this work. The new method based on an analysis of the JPEG algorithm, in which it uses the value of the mean and the standard deviation of each cover blocks to embed the secret message, where the cover image blocks calculated in the same manner of the JPEG algorithm. Two standard images that differ in their amount of texture (Lena and The Baboon images) are used to test the new method; an analysis and discussion are presented for the results of applying this method which proved the validity of this method to override the JEPG attack.

   

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Title: Flower image segmentation using watershed and marker controlled watershed transform domain algorithms
Author (s): B. K. V. Prasad, M. V. D. Prasad, Raghava Prasad, N. Sasikala and Sunita Ravi
Abstract:

Watershed and marker-controlled watershed transform domain methods are the one of the powerful tools for image segmentation. Segmentation and recognition are two primary stages in the development of a fully digitized flower identifier for real time use. This paper limits the following discussion to flower image segmentation only. The objective of this work is to study and explore flower detection and segmentation algorithms with watershed transform. Two variants of watershed transform with morphological gradients and wavelet coefficients are proposed. The flower segmentation problem uses watershed and marker-controlled watershed algorithm during the initial phases. This transformed into a wavelet based fusion model with binary flower images in the later stages giving reasonable segmentation outputs. The segmentation results are analysed both visually and mathematically. The average segmentation distance error (SDE) and structural similarity index (SSIM) on Oxford university flower dataset is around 0.485 and 0.786 respectively.

   

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Title: Capacity estimation of urban road in Baghdad city: A case study of Palestine arterial road
Author (s): Zainab Ahmed Alkaissi
Abstract:

Palestine urban street one of the most important urban arterials rods in Baghdad city. Severe congestion conditions at PM peak time periods (4:00-9:00) which become very concern problems regarding its location which considered as one of the most attractive region in Baghdad city due to the mixed land use surrounding this urban arterials road. In this research two links are selected namely as Link (1) from Al-Mawall Intersection to to Al-Nakhla Intersection and Link (2) from Al-Nakhla Intersection to Al-Skharah Intersection. The results of hourly traffic flow rate showed scattering of observed data and there is no fitting relation between flow and speed for both Link (1) and link (2). The absence of both commitment and responsibility for traffic rules, poor pavement surface conditions, illegal on street parking conditions that reduced number of lanes; driver behaviour of sharing carriageway and disturbance manoeuvres ..etc., due to all these factors the direct empirical method for capacity estimation are adopted based on observed volume and fundamental diagram method. The heavy congestion conditions for south direction of link (1) and north direction for Link (2) with V/C ratio of 1.2 and 1.4 respectively. Also the saturation conditions occurs at Link (1) and (2) at jam density of approximately (100 veh/km, 58 veh/hr, 60 veh/hr, 70 veh/hr ) for south and north directions respectively.

   

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Title: Study and optimization of a CAD/CFD model for valveless pulsejets
Author (s): Luca Piancastelli, Stefano Cassani, Eugenio Pezzuti and Luca Lipparini
Abstract:

The method introduced in this paper aims to find a feasible method to evaluate the static thrust of a “valveless” pulsejet, starting from a CAD model. CFD (Computational Fluid Dynamic) simulation and golden section were used for this purpose. Even for new pulsejet designs, it is possible to evaluate the pulsating frequency from equations available in literature or with a mono-dimensional pressure wave model. Then the combustion energy should be introduced in the engine. In this CFD model, the heat flow due to the combustion is simulated through the application of a pulsating flow of hot gases through the walls of the combustion chamber. To minimize the error of this added flow, a stoichiometric combustion of pure oxygen is introduced. The temperature value of the hot gases was optimized with the Golden Section Method in order to obtain the same experimental results of the Department of Aerospace Engineering of California Polytechnic State University, San Luis Obispo [2]. In this way, it is possible to evaluate the performance of a new design of different geometry and size. In fact, a flow with the same temperature can be introduced through the wall of the combustion chamber. The mass flow rate can be trimmed to obtain a mass balance between the incoming and the outgoing gases. In this way, the thrust can be calculated. The fuel type is not very influent for pulsejet performance.

   

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Title: The paradigm of ecological sustainability of kalmykia meliorative rice agro-landscapes
Author (s): Aleksey Semenovich Ovchinnikov, Viktor Vladimirovich Borodychev, Viktor Sergeevich Bocharnikov, Elvira Batyrevna Dedova, Sergey Denisovich Fomin, Olesya Vladimirovna Bocharnikova and Elena Sergeevna Vorontsova

Abstract:

Evaluation of the rice meliorative systems operating mode of Kalmykia Republic is presented in the article and shows the criteria of negative processes, such as secondary salinity and salinization of soils, for which the value of hydroecological risk is unacceptable and is within 0.42 and 0.69 respectively. Complex of measures, tools, chemical and biological melioration methods is offered to maintain the melioration situation at an acceptable level, such as reconstruction of the collector drainage system; improving of conditions for removal of waste and drainage waters from the site territory; observance of the washing irrigation regime of soils with the removal of salts with drainage water; regular capital and current planning of map’s checking with bringing the level of the surface to a constant level with variation ± 3...5 cm from zero plane; improving the structure of rice crop rotation; carrying out activities for chemical melioration saline and saltmarsh soils. The results of rice agro-landscapes design research years are presented with the inclusion of improving meliorative crops to the crop rotation, which are capable to increase bio-energy productivity of agro-ecosystem and to provide a positive humus balance, an increasing in rice soil’s fertility, an agricultural landscapes productivity in case of minimum energy costs. Ecological efficiency of resource-saving technologies of dry upland crops cultivation is proved, due to the formation of high harvests without watering with the use of after-rice residual moisture reserves (280…300 mm). Melioration impact ecological efficiency of crops-ameliorants in rice rotation is improvement of water-physical properties (total porosity and aeration porosity increase by 5…7% and 9…12% respectively); reduction of the composition density by 7.52…10.3%; the increase in the number of the most agronomically valuable soil aggregates (0.25…10 mm) by 9.95…16.04%; the increase in the structure coefficient from 0.9 to 1.7…1.9; reduction of the groundwater level and territory flooding risk by 35%. The plowing of plant residues (from 4.0 to 14.8 t/ hectare) allows to increase the humus content by 15…18%, improve the phytosanitary condition of rice fields (by 42…75%), increase the rice grain yield by 0.39…1.13 t/hectare.

   

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Title: Design and development of Trunnion hydraulic fixture for reducing cost and machining time of base jaw
Author (s): Bhuvanessh R. C. and J. Senthil Kumar
Abstract:

A fixture is designed and built to hold, support and locate every component to ensure that it is machined with accuracy. The recent trends in the industry are towards adopting the hydraulic and pneumatic techniques because it saves time and machining cost gets reduced. By using computer-aided fixture design technique the designer creates a model of fixture and carried out finite element analysis on fixture model by considering given boundary condition before getting manufacture and can see deficiency and could make modification accordingly without getting it manufactures, which saves a great amount of money and time. In this project, the same methodology is adopted for designing analyzing the designed Trunnion hydraulic fixture. The Trunnion hydraulic fixture is designed for Master Jaw of the chuck to perform milling, undercut and drilling operations using Vertical machining centers. Computer-aided fixture design of fixture assembly is carried out using SOLIDWORKS 2017 software and Finite element analysis of fixture and cylinder block is carried out using ANSYS Static workbench software.

   

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Title: Analysis of branched aspiration ducts networks with swirling flow of gas and dust passing through the ducts
Author (s): Dmitry P. Borovkov, Elena O. Cherevychenko, Konstantin O. Chichirov and Alexander G. Averkin
Abstract:

The paper describes a method of aerodynamic analysis of branched aspiration networks with swirling flow in air ducts. The proposed technique is based on equivalent local resistances method. The proposed method is intended for aspiration networks in which tangential swirling device are used instead of standard tees. This technique makes it possible to obtain exact values of aspiration gas flow passing through parallel sections of the duct network, without any recourse to iterative methods.

   

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Title: Performance evaluation of the SCP-MAC: A medium access control protocol for WSN
Author (s): Albeiro Cortes Cabezas and Jose de Jesus Salgado Patron
Abstract:

This paper studies the main performance characteristics of the SCP protocol, a medium access control protocol for sensor networks (WSN). SCP-MAC was designed taking into account the characteristics of energy shortage and processing capacity of the sensor nodes and seeks to reduce the consumption of energy at the expense of other performance parameters such as delay, flow and bandwidth. Our contributions through this work are the following: first, a physical layer model corresponding to the radio transmitter/receiver CC2420 was implemented in Qualnet®, including a model of energy consumption and a model of the SCP protocol based on the specifications of the authors; second, a detailed performance analysis of the protocol was made based on different metrics.

   

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Title: Neural network modelling of the process of methylbutene dehydranation into isoprene
Author (s): Denis R. Shaimukhametov, Sofya I. Mustafina, Dina V. Shaimukhametova and Svetlana A. Mustafina
Abstract:

The process of C5H10 hydrocarbon dehydrogenation consists of turning isopenthane into methylbutene and its compounds, or into isoprene with an oxide ferric potassium catalyst. When operating in a commercial reactor for several thousand hours, a ferric potassium catalyst gradually loses its activity. In the commercial operation, the catalyst is activated at times with water vapour. However, frequent regenerations are unfavorable as they result in a gradual change in the treatment phase content of the catalyst in the circle: reaction – regeneration. Thus, it is typical to modernize the isoprene production processes on the basis of hydrocarbon material. Namely, to construct new mathematical models, making it possible to forecast properties of the basic process factors. This paper is devoted to the construction of a mathematical model using differential equations and an artificial neural network for the catalyst process of methylbutene dehydrogenation into isoprene, providing the reagent changes in time and reactor length. Simultaneously, the given neural network made it possible to consider the peculiarities of the chemical process and foresee the concentration of the target product (isoprene), and how they depended on the changes in the parameters of the setting and composition of the source substances of the reaction compound.

   

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Title: Performance evaluation of network topology for ad-hoc wireless sensor network using Ant Colony Optimization routing technique
Author (s): Ali H. Hamad
Abstract:

In an ad-hoc wireless sensor network systems, the life time of sensor nodes is a crucial issue to ensure sustained functionality of the network. For a multi hop wireless sensor network the routing protocol used plays an important role in prolong the life time of the nodes. In this work, a routing technique based Ant Colony Optimization technique has been used and performance evaluation of different network topology is studied such as flat and clustered network. The system has been tested using six Telosb sensor nodes programmed with nesC language based Tinyos 2.1.2 under Linux operating system. Also a python program has been used to monitor the performance of the network and collect the required data. The obtained results shows a good performance in power consumption when using clustering technique rather than other network topologies.

   

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Title: Efficient power transmission system using mesh & reflected impedance coupling methods for medical implants
Author (s): Saad Mutashar and Abbas H. Issa
Abstract:

In this paper, the mathematical analysis and optimization of inductive power transmission system with serial to parallel topology for implanted biomedical devices is presented. The mathematical analysis based on the mesh coupling method is used to determine the dissipated power on the implanted remote electronics. In addition, the reflected impedance method is used to calculate and optimized the efficient power transmission without and with the power amplifier resistance. The proposed relative distance separated between the two sides of the inductive link is 6 mm with a coefficient factor 0.09 and the remote load resistance is 300 O. The results show that efficiency with low input impedance is 78% and with higher input impedance is 40%. The efficiency is reduced approximately 51% when the power amplifier resistance is used as a series resistance with the transmitted LC-tank. The system optimization can be achieved by tuning the capacitor at the received LC-tank. The mathematical analysis is modeled and simulated in MATLAB.

   

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Title: Development of a simulation model of protected wireless sensor network
Author (s): E. Basan, O. Makarevich and N. Tsopcalo
Abstract:

This research is devoted to protection of wireless sensor networks (WSN) that is capable of counteracting a wide spectrum of active intrusions. The importance of this problem is caused by the recent increase of popularity of wireless sensor network in the industry and in the military and the lack of protection means that take particular features of WSN into account and can effectively repel active attacks. The aim of this research is to develop a WSN simulation, which would allow to evaluate state of nodes using several trust evaluation approaches and to compare the result with the proposed method. Trust level computation uses three main parameters for node state evaluation, which allows expanding the scope of detected attacks.

   

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Title: Comparative study of turbulent incompressible flow past NACA airfoils
Author (s): Aslam Abdullah, Amirul Aizad Roslan and Zamri Omar
Abstract:

The flow past the airfoils is continuously investigated in various experimental and computational aerodynamic perspectives. In this paper, a comparative study on the aerodynamic characteristics of the turbulent incompressible flow past four NACA airfoils is emphasized. Particularly, we classify these characteristics based on the basic geometries, namely symmetric and asymmetric airfoils, as well as trailing edge angles. The results confirm the general aerodynamic theory and include finding on the effect of sharp trailing edge, which complement the available airfoil datasets for improving their designs and as reference cases.

   

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Title: Cascade neural-fuzzy model of analysis of short electronic unstructured text documents using expert information
Author (s): Dmitry Tukaev, Olga Bulygina, Pavel Kozlov, Anatoly Morozov and Margarita Chernovalova
Abstract:

The goal of this article is to increase the efficiency of analyzing small electronic unstructured text documents in conditions of a statistical data lack for using the probabilistic methods that should be based on the application of neural-fuzzy instruments. This paper suggests a cascaded neural-fuzzy model using expert information to determine the importance of meaningful words in the formalization and subsequent rubrication of text documents based on the neural-fuzzy classifier, which allows analyzing small documents based on their unified representation. The practical use of the results is expected in creating information systems of the automated analyzing electronic unstructured text documents used in state and municipal government.

   

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Title: Development of the process for stamping of forged parts made of granules of Al-Zn-Mg-Cu system alloy
Author (s): Belokopytov Vasilij I., Gorokhov Yuruy V., Konstantinov Igor L., Uskov Igor V., Lesiv Elena M., Gubanov Ivan Y., Zadvorny Alexander G., Kirko Vladimir I., Koptseva Natalia P. and Katryuk Victor P.
Abstract:

The influence of temperature and the speed parameters of the stamping process on the mechanical properties of forged parts have been studied. It has shown that in terms of the plasticity of the workpiece, stamping benefits most favorably from the mode improving the mechanical properties of the finished product. Similarly, but to a lesser extent, the stamp temperature influences the mechanical properties of the stamp. It has been established that the highest level of mechanical properties of stamped forged parts is achieved at stamp and workpiece heating temperatures ranging between 300–350°C and intensity of shear strain speed.

   

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Title: A novel and secured intrusion detection system for wireless sensor networks using Identity Based Online/Offline Signature
Author (s): S. Balakrishnan, B. Persis Urbana Ivy and S. Sudhakar Ilango
Abstract:

Mobile Ad hoc network (MANET) is a gathering of versatile hubs furnished with both a remote transmitter and a receiver that speak with each other by means of bidirectional wireless links either straightforwardly or in a roundabout way. Because of the accessibility of ease gadgets, open medium, wide dispersion of hubs, evolving topology, no incorporated observing and its capacity to give moment remote systems administration abilities MANET is defenseless against vindictive assaults and it's a subject worth research. So security of information and distinguishing the getting into mischief hub is undoubtedly. To defeat this, we propose a procedure on the web/disconnected character based mark plot for the wireless sensor network (WSN). Identity Based Online/Offline Signature (IBOOS) moreover decreases the computational overhead for convention security, which is basic for WSNs. In IBOOS security depends on the hardness of the discrete logarithm issue. IBOOS conventions have preferred execution over the current LEACH, LEACH LIKE PROTOCOLS for CWSNs, as far as security overhead and vitality utilization.

   

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Title: Minkowski fractal geometry: An attractive choice of compact antenna and filter designs
Author (s): Hadi T. Ziboon and Jawad K. Ali
Abstract:

Various fractal geometries have been successfully applied to design compact bandpass filters and miniaturized multiband antennas for different multi-services wireless applications. In this paper, a thorough investigation of the space-filling characteristics of the classical Minkowski fractal geometry has been presented. Many variants of this geometry can be derived by using generators by varying the standard one-third ratio adopted in the traditional fractal geometry. The use of multi-ratio will result in a large number of variants with fractal dimensions that are larger or smaller than 1.465 of the normal Minkowski fractal geometry. The higher the fractal dimension, the better the fractal curve fills the given area, therefore achieving higher compactness. These variants will provide the antenna and filter designer with many choices to implement his structures.

   

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Title: Investigation of the strength properties of hybrid fibre reinforced concrete (HFRC) made with polypropylene fibre (PPF) and alkali resistance glass fibre (ARGF)
Author (s): Amaziah Walter Otunyo and Odebiyi Jacob Ayo
Abstract:

This study experimentally investigated the strength properties of hybrid fiber reinforced concrete, using polypropylene fibers (PPF) and alkali resistance glass fibers (ARGF). The fibers were added to grade 25 concrete at different proportion of 0.5%, 1.0%, 1.5% and 2.0% by percentage volume of concrete. A total of sixty three cubes samples were tested for compressive strength, twenty four cylindrical samples were tested for split tensile strength and twenty four beam samples were tested for flexural strength and ductility test. Maximum compressive strength was attained at 1.5% fiber volume with hybrid fiber ratio of 80% ARGF and 20% PPF, maximum split tensile strength was attained at 1.0% fiber volume with hybrid fiber ratio of 80% ARGF and 20% PPF. The beam samples attained it maximum flexural strength at 1.0% fiber volume with hybrid fiber ratio of 60% ARGF and 40% PPF.

   

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Title: An assessment on the state of lead acid and Zinc bromide battery in Pv-Wind hybrid system
Author (s): U. S. Ragavi, M. Nandhini Gayathiri and N. Venkatesh
Abstract:

Hybrid renewable energy systems are more reliable and economical compared to the stand-alone system which is powered by only one source. An off-grid PV-wind hybrid system is considered in this work, where the reactive power requirement of the wind-driven induction generator (IG) is met only by the battery banks when there is insufficient solar output from the PV Panels. In this work for such a design, to provide effective storage capacity, Zinc bromide battery and their parameters are scrutinized and compared with the conventional lead-acid battery. Based on the analysis and comparison the most appropriate battery type is chosen. The Storage efficiency of the batteries has been computed under two situations. In the first case the battery banks supplies both active and reactive power when there is inadequateness in solar and wind power. In the next case, battery banks supplies only reactive power for the induction generator during the unavailability of solar output from PV modules. Storage equipment analysis for different conditions, aids in selecting the most optimal battery type for the hybrid unit.

   

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Title: A survey on different techniques and approaches for low power content-addressable memory architectures
Author (s): V. V. Satyanarayana Satti and Sridevi Sri Adibhatla
Abstract:

This paper presents a survey on current trends adapted in the low power content addressable memory (CAM) architectures. CAMs are modified for the requirement of high speed, low power table look up function and are especially popular in network routers. CAM is a special type of memory with comparison circuitry. It stores or searches the look up table data with the help of one clock cycle. Large amount of power is consuming during comparison process because of parallel circuitry. CAM architectures are designed to reduce the power by eliminating the number of comparisons. In this paper at architectural level we survey different architectures for reducing dynamic power in CAM design. We reviewed seven different methods at the architectural level for low power.

   

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Title: The impact of hydrogen on the cracking resistance in weld joints of shipbuilding steels
Author (s): Muravyov K. A., Klyuev S. V., Abakarov A. D. and Trukhanov S. V.
Abstract:

The article provides information on the results of the study of hydrogen impact on the nucleation and growth of cold cracks in weld joints of shipbuilding steels. It is shown that as the hydrogen content in the weld seam increases, the crack propagation work decreases. It was found that an increase in the diffusion hydrogen content in weld metal sharply reduces its resistance to brittle fracture. The purpose of this work was an experimental study of the influence of hydrogen on the nucleation and growth of cracks in welded joints of steels used for the construction and operation of ship structures in severe natural climatic and engineering conditions. The object of the study were low-alloyed steel grades 10HSND and 15HSND, cut off from dismantled frames of sea tankers designed to transport oil. It was found that an increase in the diffusion hydrogen content in weld metal sharply reduces its resistance to brittle fracture. It has been shown that as the hydrogen content in the weld seam increases, crack propagation work Acp reduces. A decrease in the air temperature during welding to -30…-40°C and an increase in the dissolved hydrogen concentration in the weld seam to 5-8 cm3/100 g results in the increase of the ductile–brittle transition temperature by approximately 40-50°C.

   

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