bluuebunny/crossref_metadata_2025 huggingface dataset:
Stochastic Taylor expansion of derivative-free method for stochastic differential equations
Authors: Ariffin Noor Amalina Nisa , Rosli Norhayati
Published: October 2017

This paper demonstrates a derivation of stochastic Taylor methods for stochastic differential equations (SDEs). The stochastic Taylor series is extended and truncated at certain terms to achieve the order of convergence of stochatsic Taylor methods for SDEs. The systematic derivation of the expansion of stochastic Taylor series formula is presented. Numerical methods of Euler, Milstein scheme and stochastic Taylor methods of order 2.0 are proposed.
Separation time analysis of transient magnetohydrodynamic mixed convection flow of nanofluid at lower stagnation point past a sphere
Authors: Ismail Mohamad Alif , Mohammad Nurul Farahain , Shafie Sharidan
Published: October 2017

In this paper, the unsteady magnetohydrodynamics (MHD) mixed convection flow of nanofluid at lower stagnation point past a sphere is studied. Nanoparticles Cu and TiO2 with water as a base fluid are considered. The separation times of the flow as the boundary layer start to separate at the surface of the sphere are given attention. The governing boundary layer equations in the form of partial differential equations are transformed into nonlinear coupled ordinary differential equations and solved numerically using an implicit finite-difference scheme known as Keller-box method. Results of the separation times of boundary layer flow for viscous and nanofluid influenced by magnetic parameter and volume fraction are shown in tabular form and analysed. This study concluded that the separation times can be delayed by added more magnetic particles and small amount the volume fraction.
Heat transfer on rotating second grade fluid through an accelerated plate
Authors: Mohamad Ahmad Qushairi , Khan Ilyas , Jiann Lim Yeou , Shafie Sharidan , Mat Isa Zaiton , Ismail Zulkhibri
Published: October 2017

Heat transfer on an unsteady free convection rotating second grade fluid flow, which is flowing through an accelerated plate, is analyzed. The physical problem investigated is described by a coupled, linear system of partial differential equations, with appropriate boundary conditions. Laplace transform technique is applied to determine the analytical solutions of the dimensionless governing equations. The effects of various embedded parameters to the velocity and temperature distribution in the fluid are graphically illustrated and analyzed. The obtained analytical results constitutes a good verification to verify a more advance situation of the physical problem, which is described by a non-linear system and only can be solved by using approximation method.
G-jitter fully developed heat transfer by mixed convection flow of nanofluid in a vertical channel
Authors: Amin Wan Nor Zaleha , Rawi Noraihan Afiqah , Admon Mohd Ariff , Shafie Sharidan
Published: October 2017

In this study, the effect of g-jitter fully developed heat transfer by mixed convection flow of nanofluid in a vertical channel is investigated. The nanoparticles of aluminum oxide and copper with water as a base fluid are used in this study. The equations corresponding to this study are solved analytically to find the exact solutions. The results of velocity and temperature profiles with the influence of physical parameters such as mixed convection, oscillation, temperature ratio and volume fraction of the nanoparticles are plotted and analyze in details. The behavior of steady state flow is also investigated. Results shown that as mixed convection, oscillation, and temperature ratio increased, the velocity profiles increased. The conductivity and viscosity of the nanofluid are also increased due to the increase of the volume fraction of nanoparticles in the water base fluid.
MHD natural convection of ferrofluid from a fixed vertical plate with aligned, transverse magnetic field and convective boundary condition
Authors: Ilias Mohd Rijal , Rawi Noraihan Afiqah , Shafie Sharidan
Published: October 2017

The present study analyzed the influence of aligned and transverse magnetic field on two dimensional natural convection boundary layer flow of a ferrofluid over a semi-infinte fixed vertical plate in the presence of convective boundary condition. It is assumed that the left surface of the plate is in contact with a hot fluid while the cold fluid on the right surface. Two different base fluids (water and kerosene) containing magnetite (Fe3O4) as ferroparticle are considered. The governing boundary layer equations along with the appropriate boundary conditions are transformed to a set of ordinary differential equations using similarity variables. The resultant system of equations is then solved numerically by using Keller-Box method.  Numerical results for the skin friction coefficient and local Nusselt number were presented whilst the velocity and temperature profiles illustrated graphically and analyzed. The effect of the inclined angle, magnetic field parameter, volume fraction, Grashof number and Biot number on the flow field were discussed. It is found that the heat transfer rate at the plate surface with Fe3O4- kerosene ferrofluid is higher than Fe3O4- water.
Structural characterization of sulphate borophosphate glasses containing calcium oxide
Authors: Yamusa Yamusa Abdullahi , Hussin Rosli , Wan Shamsuri Wan Nurulhuda , Dalhatu Sadiq Abubakar , Aliyu Aliyu Muhammad , Bulus Ibrahim
Published: October 2017

Increasing demands for better perfoming glasses have lead to current investigating of the sturctural properties of glasses for optimum performances. Calcium sulphate borophosphate glasses of different compositions were prepared using melt quenching technique. The glass forming ability and stability were checked using Differential thermal analyzer (DTA). Density and molar volume had been evaluated and analyzed. From the results of XRD, the absent of discrete and continuous sharp peaks confirmed the amorphous nature of the glass compositions while the results from both IR and Raman revealed the existence of SO4, BO4, BO3, P-O-P and PO43-. Addition of CaSO4 to borophosphate influenced the conversion of the dominant BO3 groups to BO4 groups. The structure of the samples was mainly based on metaphosphate, diphosphate and BO4 units, which became depolymerized with addition of CaSO4 content. The glass forming ability and thermal stability were found to increase with an increase in the concentration of modifier content. Glass density and molar volume is found to be between 2.146 to 2.314 gcm-3 and 45.794 to 48.880 m3mol-1 respectively. It is observed that the density of glass increased while the molar volume also increased with respect to increase in concentration of CaSO4 in the glass compositions. We analysed our data using different mechanisms and compared the results with previous works. Our findings show that this glass could be beneficial and considered as a good candidate for optical devices applications.
Feeding ecology and food preferences of Cherok Paloh, Pahang horseshoe crab, Tachypleus gigas
Authors: Md Razak Mohd Razali , Kassim Zaleha , Sabuti Asnor Azrin , Ismail Ahmad
Published: October 2017

Intensive previous studies on horseshoe crabs feeding ecology were mostly focus on Limulus polyphemus. Their food preference might be different depend on the availability and abundance of feeds in the particular environment. This paper aims to investigate the feeding ecology and food preferences of Cherok Paloh, Pahang Tachypleus gigas. Ten samples of male and female horseshoe crabs, Tachypleus gigas were trapped in fishing net during the incoming high tide and 20 samples of male and female were hand-harvested at the spawning beach; 10 samples during pre-mating and 10 samples during post-mating. Their gut content was analysed by the Electivity Index. Results showed that Tachypleus gigas coming to spawn with full gut content. Echinoderm served as a main food composition in the gut of males (50%) and females (51.94%) during the open sea migration phase. The main composition was substituted by macrophyte (males: 59.51% to 65.15%; females: 36.36% to 58.10%) as they arrived to shore. Based on Electivity Index, male crabs showed positive preference toward polychaete (EI: 0.04) and macrophyte (EI: 0.19) at the spawning site while, the females showed positive preference toward bivalve (EI: 0.46). Further study on feeding ecology is needed in order to improve the population of Tachypleus gigas in Malaysia.
Control limit detection for source apportionment in Perlis River Basin, Malaysia
Authors: Samsudin Mohd Saiful , Khalit Saiful Iskandar , Azid Azman , Juahir Hafizan , Mohd Saudi Ahmad Shakir , Sharip Zati , Zaudi Muhammad Amar
Published: October 2017

This study presents the application of selected environmetric in the Perlis River Basin. The results show PCA extracted nine principal components (PCs) with eigenvalues greater than one, which equates to about 77.15% of the total variance in the water-quality data set. The absolute principal component scores (APCS)-MLR model discovered BOD and COD as the main parameters, which indicates the measure of the agricultural pollution in the Perlis River Basin, the hierarchical agglomerative cluster analysis (HACA) shows 11 monitoring stations assembled into two clusters in accordance with similarities in the concentration of BOD and COD, which are grouped in P4. The X ̅ control chart shows that the mean concentration of BOD and COD in P4 is in the control process. The capability ratio (Cp) was applied to measure the risk of the concentration in terms of the river pollution in a subsequent period of time using the limit NWQS.
Accuracy test in identifying the splice site type of DNA sequences by using probabilistic neural networks and support vector machines
Authors: Kerami Djati
Published: October 2017

It has been known that Probabilistic Neural Networks as machine learning is very fast in it’s computation time and give a better accuracy comparing to another type of neural networks, on solving a real-world application problem. In the recent years, Support Vector Machines has become a popular model over other machine learning. It can be analyzed theoretically and can achieve a good performance at same time. This paper will describe the use of those machines learning to solve pattern recognition problems with a preliminary case study in detecting the type of splice site on the DNA sequences, particularity on the accuracy level. The results obtained show that Support Vector Machines have a good accuracy level about 95 % comparing to Probabilistic Neural Networks with 92 % approximately.
The formation of nanoscale clusters – nanofilms / quantum dots predicted using a capillary model of nucleation
Authors: Sakrani Samsudi , Qiao Jie Lim , Wahab Yussof
Published: October 2017

This paper describes the theoretical and simulation studies of both homogenous and heterogeneous nucleation, the phenomena that refers to the formation of stable nuclei prior to the growth of nanoclusters including nanofilms and quantum dots. Essentially, a single cluster may contain few thousand of atoms, and interaction with the surface may be preceded via processes, such as diffusion, hopping, sorption and coalescences. These complicated physical-chemical phenomena require in-depth theoretical understanding on how the various interacting quantities can be formulated and then resolved using specific mathematical approximation. In the case of a capillary model for heterogeneous nucleation, the nuclei are assumed to be in spherical shapes, which increase in both energies and diameters, and finally reach their critical points and settled to oval shapes prior to dome-like wetting on the substrate, essentially just like water droplet resting on a surface. The net change of energy, ΔG for the formation of cluster is found to be the functions of nucleus volume, surface area of atomic-nucleus interface, surface area of nucleus-surface interface and energy lost at substrate-atomic interface. The results for ΔG, ΔG*, r* and Ω and their respective changes with r, s and T were obtained and experimentally verified using existing data.
Sin-Cos-Taylor-Like method for solving stiff ordinary diffrential equations
Authors: Ahmad Rokiah @ Rozita , Yaacob Nazeeruddin
Published: October 2017

This paper discusses the derivation of an explicit Sin-Cos-Taylor-Like method for solving stiff ordinary differential equations, which is a formulation of the combination of a polynomial and the exponential function. This new method requires extra work to evaluate a number of differentiations of the function involved. However, the result shows smaller errors when compared to the results from the explicit classical fourth-order Runge-Kutta (RK4) and the Adam-Bashforth-Moulton (ABM) methods. Implicit methods could work well for stiff problems but have certain drawbacks especially when discussing about the cost. Although extra work is required, this explicit method has its own advantages. Besides providing excellent results, the cost of computation using this explicit method is much cheaper than the implicit methods. We also considered the stability property for this method since the stability property of the classical explicit fourth order Runge-Kutta method is not adequate for the solution of stiff problems. As a result, we find that this explicit method is of order-6, which has been developed, and proved to be both A-stable and L-stable.
g-Jitter induced free convection boundary layer on heat transfer from a sphere with constant heat flux
Authors: Shafie Sharidan , Amin Norsarahaida
Published: October 2017

The free convection from a sphere, which is subjected to a constant surface heat flux in the presence of g-jitter is theoretically investigated in this paper. The governing equations of motion are first non-dimensionalized and the resulting equations obtained after the introduction of vorticity are solved numerically using an implicit finite difference method for a limiting case Re >> 1 or the boundary layer approximations. Table and graphical results for the skin friction and wall temperature distributions as well as for the velocity and temperature profiles are presented and discussed for various parametric physical conditions Prandtl number, Pr=0.72, 1 and 7. Results indicate that g-jitter induced convective flows is stronger when Pr is small.
Modeling and simulation of single-electron transistors
Authors: Jia Yen Lee , Mat Isa Ahmad Radzi , Ahmad Dasuki Karsono
Published: October 2017

Single-electron transistor (SET) can offer lower power consumption and faster operating speed in the era of nanotechnology. It operates in single electronics regime where only one electron can tunnel from source to drain via island. Thus single electron tunneling is the phenomena that describe the principle of SET. Owing to the stochastic nature of the tunneling event, a tunneling electron is considered as a discrete charge. To simulate the SET, Monte Carlo method is used due to its reasonable accuracy in the single electronics simulation. A model is described and used to study the electronic properties of SET. Monte Carlo method follows the tunneling path of a representative number of electrons and it can gives a clear picture of the inner work of the single electron circuits.
The quantum Hall effect: spin-charge locking
Authors: N. Shrivastava Keshav , Abdul Jalil Ithnin , Yusof Norhasliza , Abu Kassim Hasan
Published: October 2017

In two-dimensional electron gas when a large magnetic field is applied in one direction and an electric field perpendicular to it, there is a current in a direction perpendicular to both. This current is called the Hall effect. It remained without quantization until 1980 when it was found that the quantization leads to correct measurement of h/e2. Therefore the quantized Hall effect was further studied at high magnetic fields where fractional quantization was found. The fractional charge can arise from the “incompressibility” in the flux quantization. Laughlin wrote a wave function, the excitations of which are fractionally charged quasiparticles. This wave function comes in competition with charge density waves but for a few fractions it does give the ground state. If “incompressibility” is not considered and it is allowed to be compressible, the fractional charge can arise from the angular momentum which appears in the Bohr magneton in the form of g values. Usually the positive spin is considered but we consider both the positive as well as the negative values so that there is a spin-charge coupling. The values thus calculated for the fractional charge agree with the experimental data on the quantum Hall effect. We have followed this subject for a long time and hence have reviewed the subject. There are several interesting concepts which we learn from this subject. The concept of the Hall effect is quite clear particularly when combined with the flux quantization. We learn about the Landau levels and hence the boson character of electrons in two dimensions. We learn that charge becomes a vector quantity and there is spincharge coupling.
Range restricted positivity-preserving scattered data interpolation
Authors: Mt. Piah Abd. Rahni , Saaban Azizan , Abd. Majid Ahmad
Published: October 2017

The construction of a range restricted bivariate C1 ( or G1 ) interpolant to scattered data is considered in which the interpolant is positive everywhere if the original data are positive. This study is motivated by earlier work in which sufficient conditions are derived on Bézier points in order to ensure that surfaces comprising cubic Bézier triangular patches are always positive and satisfy C1 continuity conditions. In the current work, simpler and more relaxed conditions are derived on the Bézier points. The gradients at the data sites are then calculated (and modified if necessary) to ensure that these conditions are satisfied. Each triangular patch of the interpolating surface is formed as a convex combination of three quartic Bézier triangular patches. Its construction is local and easily extended to include as upper and lower constraints to the interpolant surfaces of the form z = P(x,y) where P is a polynomial of degree less or equal to 4. Moreover, C1 ( or G1 ) piecewise polynomial surfaces consisting of polynomial pieces of the form z = P(x,y) on the triangulation of the data sites are also admissible constraints. A number of examples are presented.
Can a simple structural time series model beat the random walk?
Authors: Kamil Anton Abdulbasah , Arsad Zainudin , Soon Hoe Quah , Chee Yin Yip
Published: October 2017

This paper tries to address the question that if the long run PPP holds, then there should exist a structural model which can outperform the random walk in out of sample forecasting. We propose an ARFIMA based model with log of the independent variable as an explanatory variable and make a comparison study of this structural model with the benchmark random walk model. Then, we compare our results with that as obtained by Engel and Hamilton, and by Clarida, Sarno, Taylor and Valente. We present the standard ARFIMA model and show how can make an extension of it so that it becomes a variant of ARFIMA and name it as YQ-ARFIMA, then construct a bivariate model relating the dependent variable yt and ln yt , and with that, perform an impulse response function analysis of the predictive ability of ln yt . We also transform the YQ-ARFIMA into a moving average representation, and thereafter perform the impulse response function analysis again, then make a comparison study between the standard ARFIMA and the YQARFIMA by comparing the out of sample forecasting ability of each one of them with the benchmark random walk model. After that, compare the performance of YQ-ARFIMA with that of the Markov switching model put forward by Engel and Hamilton, and the MSIH(3)-VECM as put forward by CSTV. Last, we test the robustness of the YQ-ARFIMA by fitting it into different exchange rate series spanning the five continents of the globe, then, test the consistency of the forecast by YQ-ARFIMA by a cointegration technique. By using the loss functions RMSE and MAPE, cointegration consistency in forecasts and impulse response function analysis, we have shown beyond doubt that theYQ-ARFIMA model is very much superior in forecasting ability.
Numerical Analysis of the Electrical Potential Calculation in a Transversely Isotropic Media
Authors: Mardiyati Sri
Published: October 2017

The electrical potential due to a point source of current supplied at the surface of a transversely isotropic medium is calculated using a finite element formulation. The finite and infinite elements are applied to calculate the potential for arbitrary electrical conductivity profiles. The accuracy of the scheme is checked against results obtainable using Chave's algorithm.
No-Go theorems and quantization
Authors: Zainuddin Hishamuddin , Sing Poh Toh , Mohd Shah Nurisya , Zainy Mazlinda , Zulkarnain Zuriati , Hassan Jumiah , Hassan Zainul Abidin
Published: October 2017

In this review, we would like to highlight the three known no-go theorems in quantum physics in relation to the processof quantization that maps classical observables to quantum ones. The quantization approach considered is a mixture ofIsham’s group-theoretic quantization and geometric quantization with special emphasis on underlying compact phasespace geometry of spheres. The first is Groenewold-van Hove theorem that states the obstruction of quantizing the fullalgebra of observables and in the sphere case, only limited to the spin observables plus the constant functions. Theother two are theorems of Bell and Kochen-Specker stating that the only hidden variable theories allowed by quantumphysics are nonlocal and contextual ones. We give simple examples of these no-go theorems and indicate someinteresting problems arising from them for the field of quantization.
Integrability of the KdV hierarchies via group theoretical approach
Authors: Abdul Aziz Zainal
Published: October 2017

This paper explores the integrability of the Korteweg-de Vries (KdV) hierarchies via a renowned group theoretical approach. Briefly this work employs the group representation method in identifying a (physically significant) nonlinear dynamical system as an integrable Hamiltonian system.
Silicon self-assembled growth of quantum dots grown on corning glass (7059) substrate
Authors: Sakrani Samsudi , Qiao Jie Lim , Sumpono Imam
Published: October 2017

Silicon quantum dots have been grown on corning glass (7059) substrate using a self-assembly method of physical vapour deposition. The samples were fabricated at sufficiently low sputtering rate and varying experimental conditions. Apparently, the onset of nucleation took place during the first 5 minutes of deposition, followed by a further growth of stable islands known as quantum dots, with the measured radii comparable to the predicted values. Other measurement results confirmed the existence of these dots, including the bandgap energy ∼ 1.80 eV from PL and a 2% at. silicon from EDX and possible amorphous from XRD. The nucleation parameters were predicted as follows: Free energy change per unit volume ΔGv = 2.64x104 Jmol-1; Surface energies per unit area, γLN = 1.48 Jm-2, γNS = 20.0 - 90.0 Jm-2 and γLS = 0.42 x 10-2 Jm-2; Critical energies ΔG* = 7.53x10-17 - 8.31x10-14 J; Critical radii r* = 9.0- 97.0 nm. This experimental evidence strongly support the early stage growth model of silicon quantum dot deposited on corning glass substrate.
On a subclass of β-uniformly convex functions defined by Dziok-Srivastava linear operator
Authors: M. Shenan Jamal
Published: October 2017

In this paper a new subclass of uniformly convex functions with negative coefficients defined by Dziok-Srivastava Linear operator is introduced. Characterization properties exhibited by certain fractional derivative operators of functions and the result of modified Hadmard product are discussed for this class. Further class preserving ntegral operator, extreme points and other interesting properties for this class are also indicated. 2000mathematics Subj. Classification: 30C45, 26A33.
The development of thermal lattice Boltzmann models in incompressible limit
Authors: Che Sidik Nor Azwadi
Published: October 2017

In this paper, an incompressible two-dimensional (2-D) and three-dimensional (3-D) thermohydrodynamics for thelattice Boltzmann scheme are developed. The basic idea is to solve the velocity field and the temperature field usingtwo different distribution functions. A derivation of the lattice Boltzmann scheme from the continuous Boltzmannequation for 2-D is discussed in detail. By using the same procedure as in the derivation of the discretised densitydistribution function, we found that new lattice of four-velocity (2-D) and eight-velocity (3-D) models for internal energydensity distribution function can be developed where the viscous and compressive heating effects are negligible.These models are validated by the numerical simulation of the 2-D porous plate Couette flow problem where theanalytical solution exists and the natural convection flows in a cubic cavity.
Contractual incompleteness in an extensive-form game under perfect information using Stackelberg model
Authors: Kamil Anton Abdulbasah
Published: October 2017

The paper presents the explanation of contractual commitments which are renegotiation-proof, based on “strategic default”. Under this, financial contracts must provide incentives of their own so that the parties would honor the agreement. We investigates the reach of this type of commitment within the general class of extensive form games. The result is that a renegotiation-proof contract exists which commits against every deviation from the equilibrium which would induce a revenue acceleration. AMS Subj. Classification: 91A40, 91A20 .
Detecting regime shifts in Malaysian exchange rates
Authors: Ismail Mohd Tahir , Isa Zaidi
Published: October 2017

Many financial and economic time series undergo episodes where the behaviour of the series seems to change quite dramatically. Such phenomena’s are referred to as regime shifts and cannot be modelled by a single equation linear model. Therefore to overcome this problem a nonlinear time series model is typically designed to accommodate this nonlinear feature in the data. In this paper, we use a univariate 2-regime Markov switching autoregressive model (MSAR) to capture regime shifts behaviour in both the mean and the variance in Malaysia ringgit exchange rates against four other countries namely the British pound sterling, the Australian dollar, the Singapore dollar and the Japanese yen between 1990 and 2005. The MS-AR model is found to successfully capture the timing of regime shifts in the four series and this regime shifts occurred because of financial crises such as the European financial crisis in 1992 and the Asian financial crisis in 1997. Furthermore, the significant result of the likelihood ratio test (LR test) justified the used of nonlinear MS-AR model rather than linear AR model.
Electronic and structural properties of wurtzite III-V and II-VI structures
Authors: Al-Douri Y. , Khachai H. , Khenata R. , Addou A.
Published: October 2017

The electronic and structural properties of wurtzite InN, ZnS and CdSe structures are studied using the empirical pseudopotential method (EPM). The principal energy at Γ of wurtzite InN, ZnS and CdSe compounds are calculated. Band structure of wurtzite InN, ZnS and CdSe materials are presented. Other quantity such as bulk modules by meansof our model is calculated.
Ideal convergence in n-normal spaces and some new sequence spaces via n-norm
Authors: Gürdal Mehmet , Sahiner Ahmet
Published: October 2017

In this paper we introduced some new sequence spaces using n-normed spaces and gave some preliminary result for matrix transformations between some sequence spaces. 2000 Mathematics Subject Classification. Primary 40A05, 40A45; Secondary 46A70.
Gold Nanoparticles Embedded on the Surface of Polyvinyl Alcohol Layer
Authors: Nur Hadi , Md. Nasir Sasha
Published: October 2017

A novel method for synthesizing polyvinyl alcohol (PVA) embedded gold film is presented. Gold particles, in the size range of 20 to 180 nm, were first prepared by the conventional Turkevitch method by the reduction of gold, hydrogen  tetrachloroaurate (HAuCl4) with sodium citrate in water. The resulting gold nanoparticles were characterized by ultra violet-visible (UV-Vis) absorption spectroscopy, dark-field microscopy, transmission electron microscopy (TEM) and field emission electron microscopy (FESEM). In the preparation of PVA embedded gold film, PVA was functionalized with (3-mercaptopropyl) trimethoxysilane (MPTMS) which produced a thiol functionality on the surface. Then, gold particles were embedded on the surface of partially dried functionalized PVA where the gold particles are chemisorbed onto the thiol groups. Their physical properties were studied using Fourier transform infra red spectroscopy (FTIR), FESEM, TEM and UV-Vis diffuse reflectance (UV-Vis DR). Considering that the gold nanoparticles in solution cannot possibly be recovered and reused, the PVA embedded gold film on the other hand, has potential to be reused multiple of times.
The parallelization of the Keller box method on heterogeneous cluster of workstations
Authors: Hamzah Norhafiza , Alias Norma , S.Amin Norsarahaida
Published: October 2017

High performance computing is the branch of parallel computing dealing with very large problems and large parallel computers that can solve those problems in a reasonable amount of time. This paper will describe the parallelization of the Keller-box method using the high performance computing on heterogeneous cluster of workstations. The problem statement is based on the equation of boundary-layer flow due to a moving flat plate. The objective is to develop the parallel algorithm of the Keller-box method in purpose to solve a large size of matrix. The parallelization is based on the domain decomposition, where the upper and lower matrices will be splitting into a number of blocks, which then will be compute concurrently on the parallel computers. The experiment was run using 200, 2000, and 20000 size of matrices and using 10 number of processors. The comparison was made from the results obtained from that various size of matrices by doing the analysis based on the performance measurement in terms of time execution, speedup, and effectiveness.
An intertwining of a hereditary algebra and a cohereditary coalgebra
Authors: Garminia Hanni , Astuti Pudji , Irawati Irawati
Published: October 2017

Let F be a field. It is known that if A is a finitely dimensional hereditary F -algebra then the dual A∗ =HomF(A,F) is acohereditary F -coalgebra. On the other hand if C is a finitely dimensional cohereditary F -coalgebra then thedual ( ) F C∗ =Hom C,F is a hereditary F -algebra. As a result, if C is a finitely dimensional F -coalgebra then C isa cohereditary F -coalgebra if and only if the dual C∗ is a hereditary F -algebra. In this paper we enlarge the class ofalgebras and coalgebras under consideration. Particularly we show that properties similar to the above results areobtained for a class of algebras and coalgebras over a self injective commutative ring R where the algebras andcoalgebras, as R -modules, are locally projective.
Flexural vibration of pyrocomposite solid cylinder
Authors: V. K. Nelson , S. Karthikeyan
Published: October 2017

Flexural vibration of an infinite Pyrocomposite circular cylinder made of inner solid and outer hollow pyroelectric layer belonging to 6mm-class bonded together by a Linear Elastic Material with Voids (LEMV) is studied. The exact frequency equation is obtained for the traction free outer surface with continuity conditions at the interfaces.Numerical results in the form of data and dispersion curves for the first and second mode of the flexural vibration of the cylinder ceramic - 1 / Adhesive / ceramic - 2 by taking the adherents as BaTio3 and the adhesive layer as an existing Carbon Fibre Reinforced Polymer (CFRP) or as a hypothetical LEMV layer with and without voids are compared with a pyroelectric solid cylinder. The damping is analyzed through the imaginary part of the complex frequencies.
Interval valued Fuzzy n-normed linear space
Authors: Vijayabalajia S. , Shanthib S.Anita , Thillaigovindanb N.
Published: October 2017

The aim of this paper is to introduce the notion of interval-valued fuzzy subspace with its flags and interval-valued fuzzy n-normed linear space. We define the operations intersection, sum, directsum and tensor product of intervalvalued fuzzy subspaces and obtain their corresponding flags. Further we provide some results on interval-valued fuzzy n-normed linear space. AMS Subject Classification : 46S40, 03E72.
Queues with two units connected in series with a multiserver bulk service with accessible and non accessible batch in unit II
Authors: Ayyappan G. , Velmurugan S.
Published: October 2017

This paper analyses a queueing model consisting of two units I and II connected in series, separated by a finite buffer of size N. Unit I has only one exponential server capable of serving customers one at a time. Unit II consists of c parallel exponential servers and they serve customers in groups according to the bulk service rule. This rule admits each batch served to have not less than ‘a’ and not more than ‘b’ customers such that the arriving customers can enter service station without affecting the service time if the size of the batch being served is less than ‘d’ ( a ≤ d ≤ b ). The steady stateprobability vector of the number of customers waiting and receiving service in unit I and waiting in the buffer is obtained using the modified matrix-geometric method. Numerical results are also presented. AMS Subject Classification number: 60k25 and 65k30
Reactivity and Reusability of Mesoporous Alumina Nanoparticles Modified with Sulfuric Acid and Niobic Acid in the Alkylation of Resorcinol
Authors: Ramli Zainab , Nur Hadi , Chandren Sheela
Published: October 2017

With the development of large molecule hydrocarbon processes, mesoporous alumina which possesses high surface area with narrow pore size distribution has received a great deal of attention. However, its acid properties lack Bronsted acidity and showed only Lewis acid sites, making it an inactive solid catalyst in the alkylation of resorcinol, a reaction which requires the usage of solid acid catalysts with both Bronsted and Lewis acidity. In this study, in order to introduce Bronsted acidity to mesoporous alumina, sulfuric acid (H2SO4) and niobic acid (Nb2O5.nH2O) are introduced to the alumina. The reactivity of mesoporous alumina nanoparticles (MAN), Nb2O5.nH2O/MAN and H2SO4/MAN were tested out on the alkylation of resorcinol with methyl tert-butyl ether. No product was obtained using pure MAN, while both H2SO4/MAN and Nb2O5.nH2O/MAN managed to produce butylated resorcinol. Mesoporous alumina nanoparticles incorporated with sulfuric acid produced a greater amount of dibutylated resorcinol, which theoretically is a better antioxidant compared to monobutylated resorcinol. The reusability of the H2SO4/MAN catalyst was also better as dibutylated product was still obtained even in the second use. This indicates that sulfuric acid has created a more stable and also higher strength of Bronsted acidity in alumina as compared to niobic acid.
Homeomorphism between Sphere and Cube
Authors: Idris Amidora , Ahmad Tahir , Maan Normah
Published: October 2017

In this paper, we present the construction of homeomorphism from unit sphere; S2 to unit cube; C3. On route, we produced an explicit mapping between the two topological spaces where proving by construction is mainly adopted in this work.
Magnetic Field Simulation of Golay Coil
Authors: Ahmad Rashdi Shah , Shaari Amiruddin , Teong Han Chew
Published: October 2017

In the field of magnetic resonance imaging (MRI), besides the main magnetic field and the radio frequency (RF) system, the gradient coils system also plays an important role in signal acquisition. Generally, there are 2 transverse gradient coils and 1 longitudinal gradient coil. In this research, the magnetic field (or gradient) generated by the conventional transverse coil, namely the Golay coil was mapped. The calculation algorithm of the magnetic field generated was written in C-programming language, compiled by the GNU-compiler collection (GCC) and was based on a forward analytical approach by using the Biot-Savart Law. The data was then visualized by Gnuplot. The magnetic field was successfully calculated and plotted using open-source softwares running under Ubuntu operating system and will provide valuable data especially for gradient coil designer.
Vapor-liquid solid mechanism using gold colloids for the growth of GaAs nanowires
Authors: Muhammad Rosnita , Othaman Zulkafli , Sakrani Samsudi , Wahab Yussof
Published: October 2017

GaAs nanowires were grown on the semi insulating undoped GaAs (111)B wafer by using metal organic chemical vapor deposition, MOCVD. The growth follows the vapor-liquid-solid method by applying nanoparticle gold colloid as a catalyst to forms a eutectic liquid alloy with the wafer substrate. The GaAs wafer were first dipped in the poly-L-lysine solution before 30nm gold colloid dropped on the wafer surface. The temperature growth was set at 420 ºC and the growth processes were done between 10 to 60 min. The samples structural were characterized using field emmission scanning electron microscope, FE-SEM and shows the GaAs nanowires height increased with the increasing growth time. On the top of each wire contain ball which include some quantity of Au when anlyze using energy disperve x-ray spectroscopy, EDX.
An Integral Equation Related to the Exterior Riemann- Hilbert Problem on Region with Corners
Authors: Zamzamir Zamzana , Ismail Munira , M. Murid Ali H.
Published: October 2017

Nasser in 2005 gives the first full method for solving the Riemann-Hilbert problem (briefly the RH problem) for smooth arbitrary simply connected region for general indices via boundary integral equation. However, his treatment of RH problem does not include regions with corners. Later, Ismail in 2007 provides a numerical solution of the interior RH problem on region with corners via Nasser’s method together with Swarztrauber’s approach, but Ismail does not develop any integral equation related to exterior RH problem on region with corners. In this paper, we introduce a new integral equation related to the exterior RH problem in a simply connected region bounded by curves having a finite number of corners in the complex plane. We obtain a new integral equation that adopts Ismail’s method which does not involve conformal mapping. This result is a generalization of the integral equation developed by Nasser for the exterior RH problem on smooth region. The solvability of the integral equation in accordance with the Fredholm alternative theorem is presented. The proof of the equivalence of our integral equation to the RH problem is also provided.
Sequential Algorithm of Parabolic Equation in Solving Thermal Control Process on Printed Circuit Board
Authors: Abdul Ghaffar Zarith Safiza , Alias Norma , Sham Ismail Fatimah , Mohamed Murid Ali Hassan , Hassan Hazrina
Published: October 2017

This paper focuses on the implementation of sequential algorithms for the simulation of parabolic equation in solving the thermal control systems. The platform of the temperature behaviour prediction is based on printed circuit board. The numerical finite-difference method (FDM) is used to design the discretization of these partial differential equations. The results of finite-difference approximation are presented graphically. Numerical methods that are used in solving the problem are the method of Jacobi, Gauss-Seidel, Red-Black Gauss-Seidel, Successive Over Relaxation (SOR) and Red-Black Successive Over Relaxation. The numerical analysis is treated done in terms of time execution, computation complexity, number of iterations, accuracy and convergence rate.
Simulation Analysis of Ad-Hoc On-Demand Distance Vector Routing Protocol Performance in Mobile Ad Hoc Network Using Taguchi Design Approach
Authors: Mohameda Hazura , Lee Muhammad Hisyam , Sarahintub Mazalan , Salleh Shaharuddin , Sanugi Bahrom
Published: October 2017

Mobile ad-hoc network routing protocol performance is evaluated mostly through simulative studies. One-factor-at-atime approach is commonly used to quantify the effect of various factors on the protocol performance. In this work, the effect of several factors was investigated simultaneously and speedily with the application of Taguchi design of experiments. The effect of the factors which include terrain size, node speed, network size, transmission range, transmission rates, pause time, and maximum connection on routing overhead was quantified. Analysis signal-to-noise ratio was performed to determine the best possible combination of factors and analysis of variance (ANOVA) was carried out to identify the significant factors that affect the routing overhead. The results showed that network size, transmission range and maximum connection play a significant role in minimizing routing overhead. The results were confirmed experimentally at 95% confidence interval.
The Numerical Techniques for Thermal Distribution Analysis in Optical Waveguides
Authors: Yaacob Maslina , Ibrahim Mohd Haniff , Mohd Kassim Norazan , Mohammad Abu Bakar
Published: October 2017

In this paper, the analysis of thermal distribution in planar optical waveguide cross-section when a single heater electrode applied is presented. Starting from the heat equation, the thermal analysis has been done using two proposed numerical methods which are include finite difference method (FDM) and finite element method (FEM). By considering conduction as the only heat transfer mechanism, the obtained results from the mentioned methods are shown to have a good agreement.
Analytical Study of Drift Velocity in Low Dimensional Devices
Authors: T. Ahmadi Mohammad , Saad Ismail , A.Riadi Munawar , Ismail Razali , K.Arora Vijay
Published: October 2017

Understanding of quantum limit in low dimensional devices helps to develop the new device types same as Carbon Nanotube Field Effect Transistor (CNTFET) and Naonowire. For each dimensionality the limitations on carrier drift velocity due to the high-field streaming of otherwise randomly velocity vector in equilibrium is reported. The results are based on the asymmetrical distribution function that converts randomness in zero-field to streamlined one in a very high electric field. The ultimate drift velocity for all dimensions is found to be appropriate thermal velocity for a nondegenerately doped sample of silicon, increasing with the temperature, but independent of carrier concentration. However, the ultimate drift velocity is the Fermi velocity for degenerately doped silicon increasing with carrier concentration but independent of the temperature.
Determination of Chromium(VI) Reduction by Acinetobacter haemolyticus using X-ray Absorption Fine Structure Spectroscopy
Authors: Hsiao Pei Quek , Shahir Shafinaz , Tao Liu , Ahmad Wan Azlina
Published: October 2017

Several types of microorganisms have been reported to reduce Cr(VI) to the less toxic Cr(III) via enzymatic reactions. The main purpose of this study is to determine the reduction of Cr(VI) by a locally isolated bacterium, Acinetobacter haemolyticus (A. haemolyticus) using the x-ray absorption fine structure (XAFS) spectroscopy. XAFS analysis consisted of both the x-ray absorption near-edge structure (XANES) and extended x-ray absorption fine structure (EXAFS) spectra. XANES spectra of the rinsed Cr(VI)-laden A. haemolyticus biomass indicated that chromium was only present in the form of Cr (III). The nearest atoms coordinated to Cr(III) were oxygens in an octahedral geometry. The longer Cr-O bond lengths (~1.97 Å) obtained from the EXAFS spectra corroborated the presence of chromium as Cr(III) bonded to oxygen. These findings demonstrate the ability of A. haemolyticus to reduce Cr(VI) to Cr(III) that was bound to oxygen atoms of the ligands in A. haemolyticus.
Sequence of Fuzzy Topographic Topological Mapping
Authors: Jamaian Siti Suhana , Ahmad Tahir , Talib Jamalludin
Published: October 2017

Fuzzy Topographic Topological Mapping, shortly FTTM, is a model for solving neuromagnetic inverse problem. FTTM consist of four topological spaces and connected by three homeomorphisms. FTTM 1 and FTTM 2 were developed topresent 3-D view of an unbounded single current source and bounded multicurrent sources, respectively. Liau Li Yun (2006) showed that FTTM 1 and FTTM 2 are homeomorphic and this homeomorphism will generate another 14 FTTM. She then conjectured if there exist n elements of FTTM then the numbers of new elements are n4 − n . The 1purpose of this paper is to study the geometrical features of FTTM. In the process, several definitions were developed which may be used to prove the conjecture. This paper will show the proof of the conjecture and their extension result.
Preparation of Ordered Mesoporous Alumina Particles via Simple Precipitation Method
Authors: Ramli Zainab , Saleh Rozaina
Published: October 2017

Several mesoporous alumina samples have been successfully prepared via simple and easy precipitation method by using inexpensive inorganic aluminium salts with ammonium acetate as precipitating agent. The aluminium acetate (Al(CH3COO)3) precipitate obtained was treated with nitric acid, acetone and ultrasonication to obtain mesoporous alumina. FESEM of the samples prepared from the treatment of nitric acid showed agglomeration of spherical nano-sized particle while TEM micrographs showed homogenous nano-sized pores in the range of 7-9 nm which agrees with data from nitrogen adsorption analysis. Al(CH3COO)3 treated with acetone followed by ultrasonic treatment exhibits narrower pore size distribution between 3.5-5.0 nm with higher surface area (198.36 m2/g) as compared to the sample without ultrasonic treatment. Acidity study of the alumina sample using pyridine adsorption indicates that the sample exhibits Lewis acidity.
Enantioseparation of Penconazole, Myclobutanil and Triadimefon by Cyclodextrin-Modified Micellar Electrokinetic Chromatography
Authors: Wan Ibrahim Wan Aini , Hermawan Dadan , Sanagi M. Marsin
Published: October 2017

Simultaneous enantioseparation of three chiral triazole fungicides i.e. penconazole, myclobutanil and triadimefon bycyclodextrin-modified micellar electrokinetic chromatography (CD-MEKC) under acidic condition was investigated withdifferent HP--CD concentrations as chiral selector. The three triazole fungicides have an asymmetrically substitutedcarbon atom respectively, and they all contain two enantiomers. In order to achieve the best enantioresolution of thesetriazole fungicides, the HP--CD concentration range was optimized from 0 to 40 mM in 10 mM increment. The resultsindicate that separation of enantiomers was not achieved with concentration range of HP--CD from 0 to 20 mM.Simultaneous enantioseparation was successfully achived at 30 mM and 40 mM HP--CD concentration in 25 mMphosphate buffer (pH 3.0) solution that containing 50 mM SDS, 10% methanol and 5% acetonitrile. However,enantioresolution decreased for myclobutanil and triadimefon enantiomers with HP--CD concentration greater than 30mM. In addition, an increase in the concentration of HP--CD caused a significant increase in the analysis time. In light ofthese aspects, the optimal concentration for HP--CD was decided to be 30 mM for the simultaneous chiral separation ofthe three triazole fungicides with resolutions (Rs) between enantiomers for penconazole, Rs = 0.81; myclobutanil, Rs = 1.14;triadimefon, Rs = 2.09; peak efficiencies (N) greater than 108 000 for all stereoisomers and analysis time of less than 15min.
Structures And Bandgaps Of Small Range Gallium Arsenide Nanocluster
Authors: Musa Nor Muniroh , Mat Isa Ahmad Radzi , Kasmin Mohd Khalid
Published: October 2017

There is currently a lot of excitement about Gallium Arsenide nanoclusters due in part to the prediction that smallenough GaxAsy clusters will act as “quantum dot” whose bandgaps can be tuned by varying the cluster size. Small range GaAs clusters ( x + y /10) were studied by using first principles calculation where structural properties and bandgap were investigated. We obtained the results of bandgap which are larger than the simulated bandgap of bulk GaAs. In this paper, we discuss the effect of GaAs cluster size to the energy bandgap.