bluuebunny/crossref_metadata_2025 huggingface dataset:
INVESTIGATION OF GLASS PLATE FAILURE MECHANISM SUBJECTED TO COPPER AND STEEL PROJECTILE IMPACTS
Authors: Shah Qasim H. , Aung Kyaw M.
Published: October 2018

ABSTRACT: A glass plate was subjected to impact by spherical copper and steel projectiles at low velocities. The glass failure features consisted of a central Hertzian cone made up of comminuted glass and a spider web like cracking pattern around the cone with circumferential and radial cracks. The objective of the investigation was to determine if the damage caused by copper projectile impact compared to steel projectile impact was higher for the same kinetic energy (K.E.) projectiles and the reason for this phenomenon. For the constant K.E. impact, copper projectile apparently caused higher damage in glass plate. Higher damage was attributed to projectile contact duration and the contact area between the projectile and the glass plate. Finite element analysis using LS-DYNA based upon maximum principal strain failure criterion for laminated glass model was able to predict the failed material under the impact location and the cracking pattern in the glass plate for a biased meshing scheme. Radial cracks in glass target were reported to be 15% higher for copper projectile impact than the steel projectile impact. ABSTRAK: Kepingan kaca dikenakan impak oleh projektil kuprum dan keluli berbentuk sfera pada halaju rendah. Ciri-ciri kegagalan kaca terdiri daripada kon berpusat Hertzian yang melibatkan kaca yang hancur dan corak pecahan berbentuk sesawang lelabah pada keliling kon dengan retakan lilitan dan jejarian. Tujuan penyelidikan adalah untuk menentukan sebab bagaimanaÂ  dengan projektil tenaga kinetik yang sama, kerosakan yang diakibatkan oleh impak projektil kuprum berbanding dengan impak projektil keluli adalah lebih tinggi. Untuk impak tenaga kinetik yang malar, projektil kuprum didapati menyebabkan kerosakan yang lebih ke atas kepingan kaca. Kerosakan lebih disebabkan oleh tempoh sentuhan projektil dan kawasan sentuhan di antara projektil dan kepingan kaca. Analisis unsur terhingga menggunakan LS-DYNA berdasarkan kriteria kegagalan terikan utama maksima untuk model kaca berlamina.Â  Kaedah ini berupaya menjangkakan kegagalan objek pada lokasi impak dan corak retakan pada kepingan kaca untuk skim berjejaring terpincang.Â  Retakan berjejari pada sasaran kaca didapati 15% lebih tinggi untuk impak projektil kuprum berbandingkanÂ  dengan impak projektil keluli.
SEALING PERFORMANCE OF GASKETED FLANGE JOINTS â€“ A PARAMETRIC STUDY
Authors: Abid Muhammad , Chattha Javed A , Khan Kamran A , Wajid Hafiz A
Published: October 2018

ABSTRACT: This paper aims at finding the leak rate through ANSI class#150 flange joints using compressed asbestos sheet gasket under combined structural and thermal transient loading conditions. The solution is obtained using two different leak rate models and two different bolt up values. The gasket compressive strain based model employs strains that are determined using finite element analysis. The other model is based on the porous media theory in which gasket is considered as porous media. Leak rates determined using these leak rate models are compared for different tightness classes and discussed. ABSTRAK: Kajian bertujuan mencari kadar bocor menerusi sambungan bebibir kelas ANSI#150 menggunakan gasket kepingan asbestos termampat di bawah kondisi bebanan gabungan struktur dan terma fana. Solusinya diperolehi dengan menggunakan dua model kadar bocor yang berbeza dan dua nilai atas bolt yang berlainan. Model terikan berasaskan pemampat gasket menggunakan terikan yang ditentukan dengan analisis unsur terhingga. Model yang lainnya berasaskan teori bahantara berongga di mana gasket digunakan sebagai medium. Kadar bocor ditentukan dengan menggunakan model kadar bocor, yang kemudiannya dibandingkan pada kelas keketatan yang berbeza dan keputusannya dibincangkan.KEYWORDS: bolted flange; gasket; leak rate; finite element analysis; tightness class compressive strains; porous media
COUETTE FLOW PROBLEM FOR AN UNSTEADY MHD THIRD-GRADE FLUID WITH HALL CURRENTS
Authors: Azram Muhammad , Zaman Haider
Published: October 2018

ABSTRACT: In this work, we analyze Coutte flow problem for an unsteady mangneto-hydrodynamic (MHD) third-grade fluid in the presence of a pressure gradient and Hall currnts. Existing literature on the topic shows that the effecs of Hall current on Coutte flow of an unsteady MHD third-grade fluid with a prssure gradient has not yet been investigated. The arising non-linear problem is solved by the homotopy analysis method (HAM) and the convergence of the obtained complex series solution is carefully analyzed. The effects of pressure number, Hartmann number and Hall parameter on unsteady velocity are discussed via analysis of plots. ABSTRAK: Kajian dijalan untuk menganalisa masalah aliran Coutte bagi bendalir MHD gred ketiga dan arus Hall. Bagi topik ini kesan arus Hall terhadap aliran Couette dalam bendalir MHD gred ketiga tak mantap dengan kecerunan tekanan, belum pernah dikaji selidik.Â  Masalah tak linear berbangkit diselesaikan dengan kaedah analisis homotopi (HAM) dan ketumpuan solusi rangkaian kompleks dianalisa dengan teliti. Kesan nilai tekanan, nombor Hartmann dan parameter Hall terhadap halaju tak mantap diperbincangkan melalui plot yang dianalisis.KEYWORDS: Cuette; flow; hall currents; unsteady; third-grade fluid; HAMÂ
NANO-BATTERY TECHNOLOGY FOR EV-HEV PANEL: A PIONEERING STUDY
Authors: Rahman Ataur , Rashid M. , Mohiuddin A. K. M. , Hawlader M. N. A.
Published: October 2018

Global trends toward CO2 reduction and resource efficiency have significantly increased the importance of lightweight materials for automobile original equipment manufacturers (OEM). CO2 reduction is a fundamental driver for a more lightweight automobile. The introduction of Electrical Vehicles (EVs) is one initiative towards this end. However EVs are currently facing several weaknesses: limited driving range, battery pack heaviness, lack of safety and thermal control, high cost, and overall limited efficiency. This study presents a panel-style nano-battery technology built into an EV with CuO filler solid polymer electrolyte (SPE) sandwiched by carbon fiber (CF) and lithium (Li) plate. In addition to this, an aluminum laminated polypropylene film is used as the electromagnetic compatibility (EMC) shield. The proposed battery body panel of the EV would reduce the car weight by about 20%, with a charge and discharge capacity of 1.5 kWh (10% of car total power requirement), and provide the heat insulation for the car which would save about 10% power consumption of the air conditioning system. Therefore, the EV would be benefited by 30% in terms of energy reduction by using the proposed body. Furthermore, the proposed body is considered environmental-friendly since it is recyclable for use in a new product. However, the main limiting factors of the SPE are its thermal behavior and moderate ionic conductivity at low temperatures. The SPE temperature is maintained by controlling the battery panel charging/discharge rate. It is expected that the proposed panel-style nano-battery use in an EV would save up to 6.00 kWh in battery energy, equivalent to 2.81 liters of petrol and prevent 3.081 kg of CO2 emission for a travel distance of 100 km.Â KEYWORDS:Â epoxy resin; carbon fiber; lithium thin plate; energy generation; solid electrolyte battery
CHAOS CONTROL AND SYNCHRONIZATION USING SYNERGETIC CONTROLLER WITH FRACTIONAL AND LINEAR EXTENDED MANIFOLD
Authors: Pourmehdi Morteza , Ranjbar Noei Abolfazl , Sadati Jalil
Published: October 2018

In this manuscript, for the first time, a fractional-order manifold in a synergetic approach using a fractional order controller is introduced. Furtheremore, in the synergetic theory a macro variable is expended into a linear combination of state variables. An aim is to increase the convergence rate as well as time response of the whole closed loop system. Quality of the proposed controller is investigated to control and synchronize a nonlinear chaotic Coullet system in comparison with an integer order manifold synergetic controller. The stability of the proposed controller is proven using the Lyapunov method. In this regard stabilizing control effort is yielded. Simulation result confirm convergence of states towards zero. This is achieved through a control effort with fewer oscillations and lower amplitude of signls which confirm feasibility of the control effort in practice.KEYWORDS:Â  synergetic control theory; fractional order system; synchronization; nonlinear chaotic Coullet system; chaos control
A REVIEW ON LOWER APPENDICULAR MUSCULOSKELETAL SYSTEM OF HUMAN BODY
Authors: Akhtaruzzaman M. , Shafie A. A. , Khan M. R.
Published: October 2018

Rehabilitation engineering plays an important role in designing various autonomous robots to provide better therapeutic exercise to disabled patients. Hence it is necessary to study human musculoskeletal system and also needs to be presented in scientific manner in order to describe and analyze the biomechanics of human body motion. This review focuses on lower appendicular musculoskeletal structure of human body to represent joints and links architectures; to identify muscle attachments and functions; and to illustrate muscle groups which are responsible for a particular joint movement. Firstly, human lower skeletal structure, linking systems, joint mechanisms, and their functions are described with a conceptual representation of joint architecture of human skeleton. This section also represents joints and limbs by comparing with mechanical systems. Characteristics of ligaments and their functions to construct skeletal joints are also discussed briefly in this part. Secondly, the study focuses on muscular system of human lower limbs where muscle structure, functions, roles in moving endoskeleton structure, and supporting mechanisms are presented elaborately. Thirdly, muscle groups are tabulated based on functions that provide mobility to different joints of lower limbs. Finally, for a particular movement action of lower extremity, muscles are also grouped and tabulated to have a better understanding on functions of individual muscle. Basically the study presents an overview of the structure of human lower limbs by characterizing and classifying skeletal and muscular systems.KEYWORDS: Â  Musculoskeletal system; Human lower limbs; Muscle groups; Joint motion; Biomechatronics; Rehabilitation.
ON THE CORRECTNESS OF A NONLOCAL PROBLEM FOR THE SECOND ORDER MIXED TYPE EQUATION OF THE SECOND KIND IN A RECTANGLE
Authors: Djamalov Sirojiddin
Published: October 2018

In this work the correctness of a nonlocal problem from the Sobolev spaces is proved under the some restrictions to the coefficients of the considered second order mixed type equation of the second kind. Methods of proving are method of "$\varepsilon$-regularization", a priory estimates and Galerkin's method.
RECEIVER OPERATING CHARACTERISTICS MEASURE FOR THE RECOGNITION OF STUTTERING DYSFLUENCIES USING LINE SPECTRAL FREQUENCIES
Authors: Alang Rashid Nahrul Khair , Alim Sabur Ajibola , Nik Hashim Nik Nur Wahidah , Sediono Wahju
Published: October 2018

Stuttering is a motor-speech disorder, having common features with other motor control disorders such as dystonia, Parkinsonâ€™s disease and Touretteâ€™s syndrome. Stuttering results from complex interactions between factors such as motor, language, emotional and genetic. This study used Line Spectral Frequency (LSF) for the feature extraction, while using three classifiers for the identification purpose, Multilayer Perceptron (MLP), Recurrent Neural Network (RNN) and Radial Basis Function (RBF). The UCLASS (University College London Archive of Stuttered Speech) release 1 was used as database in this research. These recordings were from people of ages 12y11m to 19y5m, who were referred to clinics in London for assessment of their stuttering. The performance metrics used for interpreting the results are sensitivity, accuracy, precision and misclassification rate. Only M1 and M2 had below 100% sensitivity for RBF. The sensitivity of M1 was found to be between 40 & 60%, therefore categorized as moderate, while that of M2 falls between 60 & 80%, classed as substantial. Overall, RBF outperforms the two other classifiers, MLP and RNN for all the performance metrics considered.
LIPS TRACKING IDENTIFICATION OF A CORRECT QURANIC LETTERS PRONUNCIATION FOR TAJWEED TEACHING AND LEARNING
Authors: Altalmas Tareq , Jamil Muhammad Ammar , Ahmad Salmiah , Sediono Wahju , Salami Momoh Jimoh E. , Hassan Surur Shahbudin , Embong Abdul Halim
Published: October 2018

Mastering the recitation of the holy Quran is an obligation among Muslims. It is an important task to fulfill other Ibadat like prayer, pilgrimage and zikr. However, the traditional way of teaching Quran recitation is a hard task due to the extensive training time and effort required from both teacher and learner. In fact, learning the correct pronunciation of the Quranic letters is the first step in mastering Tajweed (Rules and Guidance) in Quranic recitation. The pronunciation of Arabic letters is based on its points of articulation and the characteristics of a particular letter. In this paper we implement the lip identification technique from video signal acquired from expert to extract the movement data of the lips while pronouncing the correct Quranic letters. The extracted lip movement data from expert helps in categorizing the letters into 5 groups and in deciding the final shape of the lips. Later the technique was then tested among a public reciter and then compared for similarity verification between the public and the professional reciter. The system is able to extract the lips movement of the random user and draw the displacement graph and compared with the pronunciation of the expert. The error will be shown if the user has mistakenly pronounced the letter and suggested for improvement. More subjects with different background will be tested in very near future with feedback instructions. Machine learning techniques will be implemented at later stage for the real time application for learning process.
A DIFFERENT APPROACH IN OPTIMUM DESIGN PROCESS AND FEA VALIDATION OF LOW-SPEED MULTI-PHASE IPMSMS
Authors: Gholamian Seyed Asghar , Gholinejad Hamid Reza
Published: October 2018

Magnets placement effects on permanent magnet motors performance, because of its different magnetic flux density distribution. Therefore, different types of magnet placement should be examined experimentally or by valid simulations. In this paper, first, an interior permanent magnet synchronous motor (IPMSM) called spoke type with specifications related to the propulsion of ships is designed and then optimized by ant colony algorithm to increase the torque-to-volume ratio. The design procedure and its formulas presented as simple as possible. Then, to verify the optimization results of the optimized motor, a Two-dimensional finite element analysis (FEA) is done. Also in this analyze the core and the slot saturation was studied.
Implementation of Layered Decoding Architecture for LDPC Code using Layered Min-Sum Algorithm
Authors: Kakde Sandeep , Khobragade Atish , Ambatkar Shrikant , Nandanwar Pranay
Published: October 2018

For binary field and long code lengths, Low Density Parity Check (LDPC) code approaches Shannon limit performance. LDPC codes provide remarkable error correction performance and therefore enlarge the design space for communication systems.In this paper, we have compare different digital modulation techniques and found that BPSK modulation technique is better than other modulation techniques in terms of BER. It also gives error performance of LDPC decoder over AWGN channel using Min-Sum algorithm. VLSI Architecture is proposed which uses the value re-use property of min-sum algorithm and gives high throughput. The proposed work has been implemented and tested on Xilinx Virtex 5 FPGA. The MATLAB result of LDPC decoder for low bit error rate (BER) gives bit error rate in the range of 10-1 to 10-3.5 at SNR=1 to 2 for 20 no of iterations. So it gives good bit error rate performance. The latency of the parallel design of LDPC decoder has also reduced. It has accomplished 141.22 MHz maximum frequency and throughput of 2.02 Gbps while consuming less area of the design.
DESIGN AND ANALYSIS OF AN AERODYNAMIC DOWNFORCE PACKAGE FOR A FORMULA STUDENT RACE CAR
Authors: Abid Muhammad , Wajid Hafiz Abdul , Iqbal Muhammad Zohair , Najam Shayan , Arshad Ali , Ahmad Ammad
Published: October 2018

This paper presents design of aerodynamic downforce generating devices (front wing, rear wing and diffuser) to enhance the performance of the Formula Student Race Car using numerical and experimental studies. Numerical results using computational fluid dynamics (CFD) studies were primarily validated with the experimental results performed in the wind tunnel. It was concluded that the use of a downforce package can enhance the performance of the vehicle in the competition.
CENTRIFUGAL COMPRESSOR EFFICIENCY CALCULATION WITH HEAT TRANSFER
Authors: Dragan Valeriu
Published: October 2018

In this paper we present a case study of apparent performance variation ofan optimized centrifugal compressor design when its metal parts are cold - before the conjugated heat transfer between the fluid and parts reaches an energetic equilibrium. The methods used are numerical, using full viscous 3D computational fluid dynamics with heat transfer. Three cases were considered, an adiabatic wall baseline, an all-blade cooling at 293 K and a more realistic stator row cooling at 293 K. Results indicate an apparent yet erroneous isentropic efficiency reading increase beyond 100% - which was to be expected due to the fluid cooling. However the isentropic and polytropic efficiencies could be estimated and were used to more accurately assess the performance of the compressor. Power consumption decreased to approximately 97% of the original load while the pressure ratio was marginally increased. This alone does not, however, explain the non-physical efficiency readings, which are mainly due to the assumptionsand manner under which the efficiency itself is calculated. The paperÂ  presents a more robust approach to measuring efficiency, regardless of the heat transfer within the turbomachinery itself. Possible applications of the study may range from cold-start regime simulation to the optimization of inter-cooling setup or even flow angle control without mechanically actuated OGV
A COMPARATIVE ANALYSIS OF EFFECT OF TEMPERATURE ON BAND-GAP ENERGY OF GALLIUM NITRIDE AND ITS STABILITY BEYOND ROOM TEMPERATURE USING BOSE–EINSTEIN MODEL AND VARSHNI’S MODEL
Authors: Al Humayun Md. Abdullah , Alam AHM Zahirul , Khan Sheroz , AbdulMalek MohamedFareq , Rashid Mohd Abdur
Published: October 2018

High temperature stability of band-gap energy of active layer material of a semiconductor device is one of the major challenges in the field of semiconductor optoelectronic device design. It is essential to ensure the stability in different band-gap energy dependent characteristics of the semiconductor material used to fabricate these devices either directly or indirectly. Different models have been widely used to analyze the band-gap energy dependent characteristics at different temperatures. The most commonly used methods to analyze the temperature dependence of band-gap energy of semiconductor materials are: Passler model, Boseâ€“Einstein model and Varshniâ€™s model. This paper is going to report the limitation of the Boseâ€“Einstein model through a comparative analysis between Boseâ€“Einstein model and Varshniâ€™s model. The numerical analysis is carried out considering GaN as it is one of the most widely used semiconductor materials all over the world. From the numerical results it is ascertained that below the temperature of 95o K both the models show almost same characteristics. However beyond 95o K Varshniâ€™s model shows weaker temperature dependence than that of Boseâ€“Einstein model. Varshniâ€™s model shows that the band-gap energy of GaN at 300o K is found to be 3.43eV, which establishes a good agreement with the theoretically calculated band-gap energy of GaN for operating at room temperature.
DETECTOR RESPONSE FROM THERMAL NEUTRON ACTIVATION OF CONCEALED EXPLOSIVES
Authors: Koreshi Zafar ullah , Khan Hamda
Published: October 2018

Explosives concealed in small quatitites (~100 g), buried in landmines or in baggage, can be detected by characteristic gamma rays produced by neutron activation. However, the detection response can be reduced by attenuation of the signal in the background medium. This paper carries out a Monte Carlo simulation, using MCNP-V, to estimate the gamma signal spectrum and intesity degradation at a sodium iodide (NaI) detector from a small sample of trinitrotoluene (TNT) explosive buried in limestone. It is found that the transmission across 25 cm of limestone is ~6% of the 2.2233 MeV hydrogen signal and ~20% of the nitrogen signal. An empirical formula, obtained from MCNP re-runs, is used to estimate the signal strength from TNT, buried at 5-25 cm in limestone, for a californium source (252Cf) emitting 2.31 x 107 n/s. It is found that for TNT mass in the range 0.1-3 kg, the signatures are in the range 20-2000 s-1 from nitrogen and 24-2400 s-1 from hydrogen. These estimates can be used to determine the scanning time for an explosives detection system.
BIOELECTROCHEMICAL BEHAVIOR OF WILD TYPE BACILLUS CEREUS IN DUAL CHAMBER MICROBIAL FUEL CELL
Authors: Islam M Amirul
Published: October 2018

Microbial fuel cell (MFC) is a bioelectrochemical system that uses bacteria as biocatalyst to oxidize organic substrates as well as release electrons, which can be harvested in an external circuit to produce electrical energy. In this study, a proteolytic biocatalyst Bacillus cereus (B. cereus) has been employed for the first time in a microbial fuel cell (MFC). The wild type pure culture was isolated from municipal wastewater and identified using Biolog Gen III analysis. The MFCs were fueled with palm oil mill effluent (POME) and attained the maximum power density of about 3.88 W/m3. The electrochemical behavior of MFC operated by B. cereus was evaluated using polarization curve, electrochemical impedance spectroscopy (EIS) and cyclic voltammetery (CV) analysis. B. Cereus excreated electron shuttling compound which significantly reduced the anode charge transfer resistance (52.95%). The FESEM result shows that B. Cereus has the capability of effective biofilm formation. These results revealed the electrocatalytic potentiality of B. cereus and which makes it a promising candidate to be used in MFCs. Therfore, this biocatlyst can be used to generate electricity through the wastewater valorization.
Computer Aided Design and Analysis of a 2-4 GHz Broadband Balanced Microstrip Amplifier
Authors: Ibrahim S. H.
Published: October 2018

In this paper, a computer-aided design and analysis of a 2-4 GHz broadband balanced microstrip amplifier using a full computer simulation program developed by the author and others is presented. A short and efficient CAD procedure for broadband amplifier design is introduced. The first step is to design an initial narrow-band high gain microstrip amplifier at 3-GHz central frequency. The second step is to optimize the initial lengths and widths of the input and output microstrip-matching circuits to get the broadband amplifier over the range 2-4 GHz. The analysis of both narrow and broadband amplifiers is investigated. In addition, with the design and analysis of a low-pass microstrip filter, the paper introduces the design and analysis of a Lange coupler. The final AC schematic diagram of the designed amplifier with the lengths and widths of microstrip lines is presented.Key Words: Computer-Aided Design and Analysis, Microstrip Amplifier, Microwave Amplifier.
Stress Analysis of Polarization Maintaining Optical Fibers by the Finite Element Method
Authors: M. Farhoud M. H. Aly A. S. Farahat, M. S. Helmi and
Published: October 2018

Stress-induced birefringence in single mode polarization maintaining optical fibers has been investigated using the finite element method. The modal birefringence caused by external forces in the Panda and the Side Tunnel fibers are calculated. It is found that the modal birefringence is directly proportional to the radial distance from the fiber center. As expected, the modal birefringence vanishes with the variation in the magnitude of the applied external loads.Key Words: Birefringence, Polarization, Panda Fiber, Side-Pit Fiber, Finite Element Method.
Analog Circuit Design Automation Tool Using Genetic Algorithms
Authors: Khalifa Y. M. A. , Horrocks D. H.
Published: October 2018

An investigation into the application of Genetic Algorithms (GA) for the design of electronic analog circuits is presented in this paper. In this paper an investigation of the use of genetic algorithms into the problem of analog circuits design is presented. In a single design stage, circuits are produced that satisfy specific frequency response specifications using circuit structures that are unrestricted and with component values that are chosen from a set of preferred values. The extra degrees of freedom resulting from unbounded circuit structures create a huge search space. It is shown in this paper that Genetic Algorithms can be successfully used to search this space. The application chosen is a LC all pass ladder filter circuit design.Key Words: Computer-Aided Design, Analog Circuits, Artificial Intelligence.
Anti-Plane Surface Disturbance
Authors: Azram M.
Published: October 2018

Solution to a problem of half-space subjected to anti-plane surface disturbance via Cagniard-de Hoop method has been investigated.  The solution is very much dependent on the choice of branch cuts, branches, and their behavior along the appropriate selected contour.  Investigations show that the contour, which simplifies the inversion integral, may or may not exist in some quadrants of x-plane and is very much dependent on the position of the point x. Consequently, the solution is the Hankel function of first kind . Key Words: Cagniard-de Hoop method. Inversion Integral. Hankel function. Anti-plane Shear. Waves propagation.  Fourier Transform.
Wear Behavior of Woven Roving Aramid / Epoxy Composite under Different Conditions
Authors: Khalid Asad A.
Published: October 2018

Wear behavior studies of aramid woven roving /epoxy composite has been conducted. Sliding the material against smooth steel counter face under dry and  lubricated with oil conditions has been investigated. Powder of Silicon carbide has been mixed with the epoxy resin and tested also. The powder was mixed in a volumetric fraction of 10% with the epoxy resin. Four Laminates of six layers were fabricated by hand lay up  method. A pin on disc apparatus has been fabricated to conduct the sliding wear tests on specimens of (4 mm   4 mm   12 mm) in size have been cut from the four laminates. The effect of sliding condition including dry, lubricated, dry with additives and lubricated with additives have been studied. Wear rate tests have been conducted at different sliding speeds and loads. Results show that the wear characteristics are influenced by the operating conditions and the construction of the composite material used. It was also found that the wear of aramid /epoxy composite onto the steel counter face were significantly reduced by using lubricant and additives but still took place.Keywords: Wear, Composite materials, Woven roving aramid, Epoxy, Additives, Lubricant.
Designing Framework of a Segmented Rubber Tracked Vehicle for Sepang Peat Terrain in Malaysia
Authors: Desa Ahmad and Wan Ishak Ataur Rahman, Azmi Yahaya, Mohd. Zohadie,
Published: October 2018

The focus of this paper is to present the designing framework of an off-road special segmented rubber tracked vehicle that may be required to run on low bearing capacity peat terrain.  To complete this study: firstly, mechanical properties of the peat terrain were first determined by using different type of apparatus. Direct shear test was performed using a Wykeham Farrance 25402 shear box apparatus to determine the internal friction angle, cohesiveness and shear deformation modulus of the peat sample. Load-sinkage test was performed using a specially made bearing capacity apparatus to determine the stiffness values of surface mat and underlying peat. Secondly, substantiate the validity of the mathematical model and finally design parameters of the special segmented rubber tracked vehicle were optimized by simulation. Keywords: Tracked vehicle, peat terrain, tractive performance.
Natural Convection Heat Transfer in Concentric Horizontal Annuli Containing a Saturated Porous Medi
Authors: R.Y. Sakr Ahmed F. Alfahaid, , Ahmed M. I.
Published: October 2018

Natural convection in horizontal annular porous media has become a subject receiving increasing attention due to its practical importance in the problem of insulators, such as ducting system in high temperature gas-cooled reactors, heating systems, thermal energy storage systems, under ground cable systems, etc. This paper presents a numerical study for steady state thermal convection in a fully saturated porous media bounded by two horizontal concentric cylinders, the cylinders are impermeable to fluid motion and maintained at different, uniform temperatures.  The solution scheme is based on two-dimensional model, which is governed by Darcy-Oberbeck-Boussinesq equations. The finite element method using Galerkin technique is developed and employed to solve the present problem. A numerical simulation is carried out to examine the parametric effects of Rayleigh number and radius ratio on the role played by natural convection heat transfer in the porous annuli. The numerical results obtained from the present model were compared with the available published results and good agreement is observed. The average Nusselt number at the heating surface of the inner cylinder is correlated to Rayleigh number and radius ratio.Keywords: Natural convection, numerical investigation, saturated porous media, finite element method, concentric horizontal annuli.
Investigation on Laf3/Si Structure as Light-Addressable Potentiometric Fluoride (Fâ€¾) Sensor
Authors: Rezaul Islam Abu Bakar Md. Ismail, , T. Yoshinobu and Hiroshi Iwasaki Koji Furuich,
Published: October 2018

In this article LaF3 films in LaF3/Si structure have been investigated for the measurement of fluoride ions in aqueous solution with higher accuracy using light-addressable potentiometric sensing technique. LaF3 films were directly grown on Si by vacuum evaporation. The effects of LaF3-thickness and annealing on the fluoride-sensitivity of the LaF3/Si structures have been studied. Accordingly four different LaF3/Si structures with various thickness of LaF3 (5/50/150nm) layer were fabricated. The structures are annealed at 400ºC for 10 minutes. The un-annealed LaF3/Si structures show very poor fluoride sensitivity. As predicted in the theoretical study structures with thinner LaF3 offer better steepness of the photocurrent characteristics that indicates better accuracy in fluoride concentration measurement. Among the annealed structures, the one prepared with 150nm LaF3 layer shows the best fluoride sensitivity of ≈ 54.5mV/pF in the range of pF1-pF4. Experimental results show a good promise for LaF3/Si structure as a light-addressable potentiometric sensor that can be used for the sensing and imaging the distribution of fluoride ion in aqueous medium with higher accuracy. Keywords: Light-addressable potentiometric sensor (LAPS), Fluoride sensor, Capacitive EIS structure
An Overview of Optical Network Bandwidth and Fault Management
Authors: Zubairi J.A.
Published: October 2018

This paper discusses the optical network management issues and identifies potential areas for focused research. A general outline of the main components in optical network management is given and specific problems in GMPLS based model are explained. Later, protection and restoration issues are discussed in the broader context of fault management and the tools developed for fault detection are listed. Optical networks need efficient and reliable protection schemes that restore the communications quickly on the occurrence of faults without causing failure of real-time applications using the network. A holistic approach is required that provides mechanisms for fault detection, rapid restoration and reversion in case of fault resolution. Since the role of SDH/SONET is diminishing, the modern optical networks are poised towards the IP-centric model where high performance IP-MPLS routers manage a core intelligent network of IP over WDM. Fault management schemes are developed for both the IP layer and the WDM layer. Faults can be detected and repaired locally and also through centralized network controller. A hybrid approach works best in detecting the faults where the domain controller verifies the established LSPs in addition to the link tests at the node level. On detecting a fault, rapid restoration can perform localized routing of traffic away from the affected port and link. The traffic may be directed to pre-assigned backup paths that are established as shared or dedicated resources. We examine the protection issues in detail including the choice of layer for protection, implementing protection or restoration, backup path routing, backup resource efficiency, subpath protection, QoS traffic survival and multilayer protection triggers and alarm propagation. The complete protection cycle is described and mechanisms incorporated into RSVP-TE and other protocols for detecting and recording path errors are outlined. In addition, MPLS testbed configuration procedure is outlined with suggested topologies. Open issues in this area are identified and current work is highlighted. It is expected that this paper will serve as a catalyst to accelerate the research and development activities in high speed networking.
Linear vs. nonlinear porosity estimation of NMR oil reservoir data
Authors: Abou Mandour Mohsen Abdou , Mohamed El-Affify Mohamed , Hassan Mohamed Hassan , Alramady Amir Kamel
Published: October 2018

Nuclear magnetic resonance is widely used to assess oil reservoir properties especially those that can not be evaluated using conventional techniques. In this regard, porosity determination and the related estimation of the oil present play a very important role in assessing the eco1nomic value of the oil wells. Nuclear Magnetic Resonance data is usually fit to the sum of decaying exponentials. The resulting distribution; i.e. T2 distribution; is directly related to porosity determination. In this work, three reservoir core samples (Tight Sandstone and two Carbonate samples) were analyzed. Linear Least Square method (LLS) and non-linear least square fitting using Levenberg-Marquardt method were used to calculate the T2 distribution and the resulting incremental porosity. Parametric analysis for the two methods was performed to evaluate the impact of number of exponentials, and effect of the regularization parameter (?) on the smoothing of the solution. Effect of the type of solution on porosity determination was carried out. It was found that 12 exponentials is the optimum number of exponentials for both the linear and nonlinear solutions. In the mean time, it was shown that the linear solution begins to be smooth at α = 0.5 which corresponds to the standard industrial value for the regularization parameter. The order of magnitude of time needed for the linear solution is in the range of few minutes while it is in the range of few hours for the nonlinear solution. Regardless of the fact that small differences exist between the linear and nonlinear solutions, these small values make an appreciable difference in porosity. The nonlinear solution predicts 12% less porosity for the tight sandstone sample and 4.5 % and 13 % more porosity in the two carbonate samples respectively.
Efficient and Compact Optical Amplifier Using EYDF
Authors: Harun Sulaiman Wadi , Dimyati K. , Tamjis M. R. , Muhd-Yassin S. Z. , Abd-Rahman M. K. , Ahmad H.
Published: October 2018

An efficient Erbium/Ytterbium doped fiber amplifier (EYDFA) is demonstrated using a 1058nm pumping wavelength, where the amplification is assisted by energy transfer between Yb and Er ions. The energy transfer increases the limit of erbium doping concentration that is imposed by concentration quenching in Erbium-doped fiber (EDF). Therefore, the gain and noise figure are severely degraded with 1480 nm pumping, where the energy transfer cannot be achieved. The use of optical isolator improves the small signal gain and noise figure by about 4.8 dB and 1.6 dB, respectively. By employing a double-pass configuration, a higher gain can be obtained with an expense of a noise figure penalty. The gain improvement of 17.0 dB is obtained at 20 mW and -50 dBm of pump and input signal powers. This shows that the double-pass configuration is an important aspect to consider when designing an efficient EYDFA.
Simbolizações de professores acerca da formação técnica integrada ao Ensino Médio
Authors: Santana Adriana Cristina Ruescas , Novaes Adelina De Oliveira
Published: October 2018

Por meio da abordagem psicossocial da Teoria das Representações Sociais, o estudo aqui relatado buscou compreender as simbolizações circulantes entre professores que vivenciaram o processo de implantação do Decreto nº 5.154/04 e da Lei 11.741/08, em uma Escola Técnica Estadual do Centro de Educação Estadual Tecnológica Paula Souza, localizada na Zona Leste da cidade de São Paulo. Os e-mails trocados entre oito professores que trabalham com o Ensino Técnico Integrado ao Ensino Médio (ETIM) em diferentes escolas técnicas estaduais na cidade de São Paulo acerca do ensino médio integrado, associados aos planos de trabalho de professores da referida escola técnica estadual do Centro Paula Souza e um documento produzido de forma colegiada sobre o ETIM pelo Sindicato dos Trabalhadores do Centro Paula Souza compõem o corpus de informações, que foi estudado respeitando-se os procedimentos da análise de conteúdo. Por meio da triangulação das fontes, foram analisadas as categorias temáticas encontradas, com vistas a propiciar a confrontação entre os três diferentes tipos de discursos elaborados pelos docentes. A pesquisa evidenciou um espectro de simbolizações destoantes, o que permitiu depreender a impossibilidade de delimitar uma representação acerca do Ensino Técnico Integrado ao Ensino Médio, vez que esse não consiste um objeto de representação para os docentes. Com base nas informações analisadas, pode-se afirmar que contribui para tal indefinição do objeto, a ausência de uma política pública de qualificação para os professores, bem como a falta de uma proposta institucional de formação integral para os alunos.
A implementação da avaliação formativa e sumativa no ensino da Educação Física.
Authors: Gonçalves Francisco Miranda , Lima Ricardo Franco
Published: October 2018

A avaliação consiste na recolha de informações necessárias para um melhor desempenho do processo de aprendizagem dos alunos. O presente estudo teve como objetivos: i) conhecer até que ponto os professores do ensino secundário recorrem à avaliação formativa; ii) perceber a importância que os professores de Educação Física atribuem à avaliação formativa. Fizeram parte do estudo 71 professores dos ensinos básico e secundário regular, assim como 850 alunos, sendo 291 do 3º ciclo, 559 do ensino secundário. De acordo com os resultados obtidos, concluiu-se que se recorre à avaliação formativa nos processos de ensino e que se atribui grande importância à mesma por parte dos professores. Verificou-se que classificação da Avaliação Sumativa tende a aumentar, relativamente à Avaliação Formativa.
Ser professor: representações sociais de docentes iniciantes de escolas privadas
Authors: Machado Laeda Bezerra , Araujo Camila Afonso Ferreira de , Evangelista Lucivânia Barbosa
Published: October 2018

Este artigo identifica as representações sociais do ser professor construídas por docentes iniciantes de instituições particulares situadas em Recife-PE. O aporte teórico utilizado foi a Teoria das Representações Sociais. Representações sociais são saberes comuns que explicam a realidade e orientam as práticas das pessoas. Trata-se de um estudo de campo que utilizou como instrumento de coleta um questionário, respondido por 20 professoras com até cinco anos de carreira. Os resultados revelam uma representação social do ser professor pautada na possibilidade de formação dos sujeitos. Essas representações sociais são marcadas pelos sentimentos de desvalorização e falta de reconhecimento social da docência.  Indicamos a necessidade de se pensar alternativas que melhor subsidiem o trabalho do docente iniciante na profissão.
La gestión educativa según el pensamiento de Jaime Caiceo: un enfoque histórico
Authors: Muñoz Estela Socías
Published: October 2018

El siguiente artículo tiene como referente la labor realizada por un educador chileno, subrayando su pensamiento y su acción en la gestión educativa en los últimos cincuenta años, fundamentada en el hecho que, desde hace un tiempo, en el contexto de mejorar la calidad de la educación, uno de los aspectos en los cuales se ha centrado la discusión en Chile, es en la gestión al interior de las unidades educativas. En efecto, el liderazgo del Director asoma como uno de los aspectos importantes a considerar. En este caso, el Dr. Jaime Caiceo Escudero, se ha destacado por el aporte en el ámbito teórico de la gestión educativa, investigando y elaborando artículos o libros, y por las acciones que ha realizado como líder educacional, impulsando la creación de instituciones (DUOC) o gestionando otras (Liceo Popular,Centro Técnico y Director Administrativo DUOC; Rector Colegio de los Sagrados Corazones, Colegio Santa Familia y Colegio Santa Isabel de Hungría). La metodología utilizada es histórico-analítica; para reconstituir su pensamiento en gestión educativa y describir su acción y liderazgo directivos, se recurrió a la metodología histórica, investigando en fuentes primarias del autor y a entrevistas de testigos presenciales. A su vez, para determinar su pensamiento se realizó un estudio analítico de sus escritos.
A PESQUISA EM EDUCAÇÃO NO BRASIL: entrevista com a professora Selva Guimarães
Authors: Bernardes Carliene Freitas da Silva , Rocha Lidiana Simões Marques , Borges Railene Oliveira , Cecílio Sálua
Published: October 2018

Esta entrevista teve como objetivo oportunizar uma reflexão sobre a Pesquisa em Educação no Brasil, a partir do conhecimento construído pela professora Dra. Selva Guimarães ao longo de sua trajetória profissional. Como técnica de coleta das informações, optamos pela Entrevista focalizada, cujo roteiro de tópicos, relativos à problemática da pesquisa em Educação no Brasil, foi construído a partir da análise do currículo da entrevistada, de leituras prévias acerca do tema, de notícias sobre pesquisa em Educação na mídia e de discussões em sala de aula, na disciplina de Epistemologia e Pesquisa em Educação do curso de doutorado do Programa de Pós-graduação em Educação da Uniube, conduzida pela professora Dra. Sálua Cecílio. A entrevista possibilitou reflexões importantes sobre a situação atual das pesquisas brasileiras em Educação, no âmbito da pós-graduação, tais como: a formação do pesquisador; o perfil dos egressos dos Programas de Pós-graduação em Educação; a interferência do mercado e das políticas públicas no direcionamento das pesquisas em Educação; o produtivismo como um dos impactos relativos aos critérios de avaliação dos Programas de Pós-graduação; o papel do gestor dos Programas de Pós-graduação; o impacto das pesquisas na realidade educacional brasileira, dentre outros.
Shakespeare, Reciprocity and Exchange
Authors: Drakakis John
Published: October 2018

In his book The Structure of World History (2014) Kojin Karatani has argued that too little attention has been paid in Marxist historiography to the issue of ‘exchange’. In a number of Shakespearean texts ‘exchange’ and ‘reciprocity’ are of vital importance in sustaining social cohesion; in Romeo and Juliet, for example, radical disruptions of patterns of reciprocity and exchange expose an ambivalence that, in certain critical circumstances, inheres in language itself. The disruption that results from the perversion of these values is felt at every level of the social order, but particularly in the sphere of the ‘economic’, where money and trade become metaphors for the disturbance of the relation between language and action, word and object. This disruption is represented as a product of ‘nature’ but it also becomes a feature of a historically over-determined human psychology, and leads to a critical examination of different forms of government and social organization.
Mechanism of Nanostructured Fluorapatite Formation from CaO, CaF2 and P2O5 Precursors by Mechanochemical Synthesis
Authors: Mofrad Raheleh Nikonam , Sadrnezhaad Sayed Khatiboleslam , Khaki Jalil Vahdati
Published: October 2018

We determined the mechanism of mechanochemical synthesis of fluorapatite from CaO, CaF2 and P2O5 by characterisation of the intermediate compounds. We used atomic absorption spectroscopy, X-ray diffraction, field emission scanning electron microscopy, FTIR spectroscopy and transmission electron microscopy to find the transitional compounds. Investigation of the binary and ternary powder mixtures revealed the appearance of H3PO4, Ca(OH)2, Ca2P2O7 and CaCO3 as the intermediate compounds. At early stages of the milling, conversions of P2O5 to H3PO4 and CaO to Ca(OH)2 occurred in the wet atmosphere. Later, a combination of Ca(OH)2 and H3PO4 formed C a2P2O7 while the unreacted CaO was converted to CaCO3 by CO2 of the ambient atmosphere. Spherical crystalline Ca10 (PO4)6F2 particles formed after 48 hours of milling due to the reaction between Ca2P2O7, CaCO3 and CaF2.
TG/DTA-FTIR Study on Total Resource Recovery from Tetra Pak Waste by Pyrolysis under a CO2 Environment
Authors: Huo Hanxin , Ma Yuhui
Published: October 2018

Pyrolysis of Tetra Pak waste under CO2 was investigated using a thermogravimetric/differential thermal analyser coupled with a Fourier transform infrared spectrometer. Experimental results showed that cellulose was decomposed between 270 and 390 °C, leading to the formation of aldehydes, ketones, carboxylic acids and levoglucosan. Thermal cracking of polyethylene occurred between 440 and 530 °C and the main products were aliphatic hydrocarbons. CO can be produced by the gasification of pyrolytic char by CO2 at temperatures ranging from 860–970 °C. Aluminium (Al) foil remained in a “thin layer shape” despite melting above 660 °C. CaO was generated from the decomposition of CaCO3 used as a paper filler at 722 °C. The reaction between CaO and the CO2 atmosphere during the cooling process led to the formation of new CaCO3 which was the main component of ash after gasification and was easy to separate from Al foil.
Nanopowder-Supported Ultra-Low Content Co–Rh Bimetallic Catalysts for Hydroformylation of Monoformyltricyclodecenes to Value-Added Fine Chemicals
Authors: Li Chengyang , Zhang Libo , Ma Yubo , Wang Tianfu
Published: October 2018

The hydroformylation of monoformyltricyclodecenes (MFTD) to diformyltricyclodecanes (DFTD) was studied systematically. A series of 0.006 wt% Rh–0.006 wt% Co catalysts supported on commercially available nanopowders such as Al2O3, ZnO, TiO2 and CeO2 was prepared by the incipient wetness method and used to catalyse the hydroformylation of MFTD to DFTD. The 0.006 wt% Rh–0.006 wt% Co/ZnO catalyst showed the highest catalytic performance among the catalysts investigated, thus 41.8% DFTD yield with 100% DFTD selectivity could be achieved. This suggested that there may be a key role of the carrier on the catalytic performance in MFTD hydroformylation. Furthermore, the kinetic profiles for MFTD hydroformylation over the 0.006 wt% Rh–0.030 wt% Co/ZnO catalyst have been examined systematically to explore the effect of reaction temperature on the catalytic performance. These results collectively suggested that a particular reaction temperature might benefit MFTD hydroformylation. There may be some agglomeration of the active sites at higher reaction temperatures.