"Annals. Computer Science Series" Journal
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Tiberiu Marius Karnyanszky
Editor-in-Chief

Annals. Computer Science Series
Tome 15, Fasc. 2


ISSN: 1583-7165 (printed journal)
ISSN: 2065-7471 (e-journal)
Owner: "Tibiscus" University of Timişoara, România
Editor: Mirton Publishing House of Timişoara, România
Distributor: "Tibiscus" University of Timişoara, România
Appearance: December, 2017


Next papers follows the review process for the Journal inclusion:

  • Abhinaw Anand, Dr. Sumathy Eswaran - A Survey of Open Source Learning Management Systems
  • Saheed Y.K., Arowolo M.O., Ibrahim S.A. - Artificial Neural Network For Breast Cancer Diagnosis
  • G. Ojemeri, S. Abdulsalam, J. F. Yayock - Mathematical Modeling of Radiative Heat Source and Magnetic Field Effects on Free Convection Flow Embedded in a Moving Vertical Permeable Plate in the Presence of Porous Medium
  • Y.K. Saheed, K. A. Gbolagade - Chinese Remainder Theorem Based Domain Name Security System
  • Popoola, Osuolale Peter and Afolabi, Mary Antinuke - Factorial analysis to investigate the effect of different levels of NPK fertilizer application on the yield of white yam
  • Yakubu A. Ibrahim, Tunji S. Ibiyemi - Automatic Speech Recognition using MFCC in Feature Extraction Based HMM for Human Computer Interaction in Hausa
  • Zakari, Y., Yau, S. A., Usman, U. - Handling Multicollinearity; A Comparative Study Of The Prediction Performance Of Some Methods Based On Some Probabiltiy Distributions
  • Muhsin Hassanu Saleh, Mukhtar Bello - Online Hospital Management System
  • Safwan Al Salaimeh - Development Of The Functional Structure Of The Computerized Control System
  • Oyeyemi, G. M., Mbaeyi, G. C. - On the Estimation of Empty cell Probabilities in a Contingency Table
  • A. Hassan, Y. Zakari - Application of First Order Differential Equation in Temperature Problems
  • Omobolaji F. Oyedokun, Elijah O. Omidiora, Ibrahim A. Adeyanju, Fagbola M. Temitayo - Analytic Approach To Face Emotion Recognition With Svm Kernels
  • Shehu A., A. Danbaba - Variance Components of Models of Sudoku Square Design
  • Samuel Omokanye, Taye Aro - Homogenous Ensembles of Data Mining Algorithms in Predicting Liver Disease
  • Muhsin Hassanu Saleh, Alimi O. Maruf - Development of an Enhanced AODV Energy Management model and Link Stability in MANET
  • Fagbola Temitayo Matthew, Egbetola Funmilola Ikeolu, Emuoyibofarhe Justice, Olaniyan Olatayo Moses, Oloyede Ayodele, Akinpelu James - e-HAMS: A Unified Model-based Integrated Healthcare Services Management System for Low-and-Middle Income Economies
  • Olagunju, M., Adeniyi, A. E. - Environmental Waste management in Ilorin Metropolis using software application
  • Owolafe O., Olanrewaju O.S. - Simulation Of An Intelligent Traffic Light Using Embedded System
  • Shervan Fekri-Ershad - Rotation Invariant Skin Detection Approach based on Combination of Probabilistic Distribution Estimation and Single Scale Retinex
  • Yakubu A. Ibrahim, Tunji S. Ibiyemi - Technical Algorithms For Efficient Optical Character Recognition System: An Overview
  • Rasheed G. Jimoh, Ridwan M. Yusuf, Yusuf O. Olatunde, Yakub Saheed - Application Of Dimensionality Reduction On Classification Of Colon Cancer Using Ica And K-Nn Algorithm
  • Adebowale Olusola Adejumo, Tobi Oladayo Oloyede, Oluyemisi Adedola Adejumo, Pelumi Emmanuel Oguntunde, Oluwole Akinwumi Odetunmibi, Nehemiah Arhoesere Ikoba, Obalowu Job - Modelling of Enugu State Monthly Rainfall Using Box and Jenkins Methodology
  • Osuolale Peter Popoola, Omotola Omotayo Dawodu, Olufemi Olusola Yusuf - Quadratic Regression and Factorial Analysis on the effect of Climatic Elements on Global Food Production and Land Nutrients in Africa
  • Osuolale Peter Popoola, Matthew Taiwo Odusina - Survey of Strategies for Teaching Statistics at School

    Next papers follows the Journal publication process:

  • Le Trung Hieu - Integrating Science in Mathematics Teaching in Vietnamese Elementary Schools
  • Abdul Orunsolu - A Smart phone-based Phishing Detector app for Electronic mails
  • Zakir Hussain, Syed Raziuddin - Completely Informed Artificial Bee Colony for Dynamic Problems and Optimal Sensor Placement
  • Paridhi Singh, Prapti Goyal,Varun S Gajendragadkar, Sayantan Pal, Vignesh S, Supreeta Balasubramanian, Sanjiban Sekhar Roy - Model analysis on Job Shop Scheduling in automobile industry using Ant Colony Optimization and Particle Swarm Optimization
  • Moses Timothy, Odey Adinye John, Okwori Anthony Okpe - An Enhanced Round Robin Virtual Machine Load Balancer for Cloud Infrastructure
  • Muhammad Farooq, Waqas Mehmood - Web 3.0 for E-Commerce Portal
  • Mohd Nazri Ismail - Implementation of Intrusion Detection System (IDS) to Prevent and Detect Multiple Attacks
  • Abikoye Oluwakemi Christiana, Garba Qudus Adeshola, Akande Noah Oluwatobi - Implementation of Textual Information Encryption using 128, 192 and 256 Bits Advanced Encryption Standard Algorithm
  • Oloyede I. - Bootstrapping Supervised classifier paradigm


    » An Enhanced Algorithm for Constructing Optimal Space-Filling Designs using Hadamard Matrices of Orders 4λ and 8λ

    » Kazeem A. Osuolale, Babatunde L. Adeleke and Waheed B. Yahya

    ABSTRACT:

    Orthogonal array Latin hypercube designs have become popular in practice among strategies used for developing computer experiments. Hadamard matrices have been used to construct orthogonal arrays based on the connection between Hadamard matrices and orthogonal arrays (OAs). A Hadamard matrix is a square matrix of +1 and -1 whose rows are orthogonal. This study aimed at proposing an enhanced algorithm that employed the maximin criterion in the k-Nearest Neighbour with Euclidean distance for constructing optimal space-filling design called Orthogonal Array Latin Hypercube Design (OALHD). Orthogonal arrays (OAs) were constructed from Hadamard matrices of orders 4λ and 8λ which are subsequently used to construct the desired OALHD. The Orthogonal array (n, k) Latin hypercube designs were constructed at parameter values of OA (n, k, s, t, λ) = (8, 7, 2, 2, 2) and (16, 8, 2, 3, 2). The OA (8, 7) LHD and OA (16,8) LHD constructed have better space-filling properties and they achieve uniformity in each dimension. MATLAB 2015 computer package was used for the development of the algorithm that constructs the OALHDs.

    KEYWORDS:

    Computer experiments, Hadamard matrices, Latin hypercube designs, Orthogonal array, Space-filling designs.

    » Received: 20 November 2016
    » Accepted: 21 July 2017

    9 - 17

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    » Development Teachers’ Mathematics Competency through Teaching Complex Numbers in High School in Vietnam

    » Tran Trung Tinh

    ABSTRACT:

    In teaching mathematics at high schools, the mathematics competency of teacher is an important procedure in teaching process. This paper, I pointed out some application of complex numbers in mathematics. And i hope it will help the teachers to develop high school their mathematics competency in Vietnam.

    KEYWORDS:

    Teachers’ mathematics competency, complex numbers, teaching methods.

    » Received: 23 May 2016
    » Accepted: 07 August 2017

    18 - 23

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    » Teaching Mathematical Modelling: Connecting to Classroom and Practice

    » Tran Viet Cuong and Le Hong Quang

    ABSTRACT:

    Teaching through the application of mathematical modelling has been concerned in recent years in Vietnam high schools. In which it clearly shows the application of the mathematical modelling with parts of life. This paper mentions to teaching and learning the AM-GM inequality and its application from theory and practice.

    KEYWORDS:

    Mathematical modelling, mathematics teaching methods, the AM-GM Inequality, theoretical and practical.

    » Received: 27 April 2017
    » Accepted: 07 August 2017

    24 - 28

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    » Contemporary Issues in Cognitive Radio Network

    » R. O. Oladele and Damilola N. Ajobiewe

    ABSTRACT:

    The paper examines contemporary issues with cognitive radio networks as it relates to spectrum scarcity and the demand of users. With recent advancement in technology and increase in the need for wireless communication systems, this has given rise to search for desirable spectrum bands for transmission. Cognitive Radios renders an answer to the trouble by sensing the idle (licensed) bands and allowing (secondary) users to broadcast and transmit in these idle spaces. Spectrum sensing forms the main block of cognition cycle. However research has shown by previous researchers that radio spectrums are being under- utilized in most cases. This paper attempts to profound a solution to efficient and effective spectrum utilization has identified the current challenges and issues faced by spectrum sensing for cognitive networks. The principal issues with cognitive radios are that it should not interfere with the primary users and should vacate the band when it is required. For this sole reason, energy detector system model was used in this paper and performance evaluation was calculated. The performance evaluation is done for cooperative spectrum sensing schemes under non fading environment This paper provides a clear understanding of cognitive radio technology, and its role in national development. Then several challenges and security issues are discussed.

    KEYWORDS:

    Cognitive Radio; Spectrum Sensing; Primary Users; Secondary Users; Wireless Communication; Spectrum Hole; Cognitive Cycle; Cognitive Capabilities.

    » Received: 26 May 2017
    » Accepted: 07 August 2017

    29 - 33

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    » Machine to Man Communication in Yoruba Language

    » Abimbola Akintola and Tunji Ibiyemi

    ABSTRACT:

    Man communicates with man by natural language, sign language, or/and gesture but communicates with machine via electromechanical devices such as mouse, and keyboard. The media of effecting machine to man be enhanced using language technology. This paper proposed a man to machine communication through Text-To-Speech system for Yoruba language. The process used involves text analysis, natural language processing and digital signal processing. The developed system shows an exhaustive representation of Yoruba language through concatenation of possible syllables in the language. The proposed model was evaluated using mean opinion score. Results showed a significant performance with an average of 92% for similarity and naturalness in the samples.

    KEYWORDS:

    Tex-To-Speech, Yoruba Language, Syllable Structure, Similarity, Naturalness, Communication.

    » Received: 22 June 2017
    » Accepted: 17 August 2017

    34 - 42

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    » Efficient RSA Cryptosystem Decryption Based on Chinese Remainder Theorem and Strong Prime

    » Saheed Yakub Kayode and Gbolagade Kazeem Alagbe

    ABSTRACT:

    Number theory has turned out to be one of the useful when it comes to computer security. For instance, number theory helps to protect sensitive data such as credit card numbers when you shop online, when online transactions is performed. The prime application of it’s is in the RSA cryptosystem. Rivest Shamir Adleman (RSA) algorithm is known to be a slower algorithm. The modular arithmetic in RSA is computationally expensive. In view of this, it has become a major challenge to implement RSA decryption in a faster manner. In this paper, we proposed an efficient method to implement RSA decryption based on Chinese Remainder Theorem and Strong prime. Three different operations, primitive traditional method, Chinese Remainder Theorem method and Chinese Remainder Theorem and strong prime criterion were used for comparisons. Our proposal achieves about 60% computational cost reduction of traditional method using Chinese Remainder method. More interesting, if the method based on Chinese Remainder Theorem and strong prime is implemented, about 84% computational cost can be reduced. Also, comparing to the Chinese Remainder method, the method based on Chinese Remainder Theorem and strong prime of RSA criterion takes about 37% of computational cost, almost 3.2 times faster than the Chinese Remainder Theorem based method. Theoretically, it was observed that our scheme is faster and it is also cheaper.

    KEYWORDS:

    RSA, RSA-CRT, Number theory, computational cost, CRT-strong prime criterion.

    » Received: 31 May 2017
    » Accepted: 07 August 2017

    43 - 47

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    » Comparative Analysis of the Efficiencies on Methods of Handling Multicollinearity in Regression Analysis

    » E. O. Ogunjobi, D. A. Agunbiade and O. A. Ayansola

    ABSTRACT:

    This paper considers three different approaches of handling multicollinearity in regression analysis using economic data. These techniques were applied to study determinants of money supply of the sector of the economy. The goal is to determine which of the economic variables included in the factors that influence money supply (either in the broad ‘M1’ or the narrow ‘M2’sense) is not actually contributing to the effect of money supply by monetary authority of the sector of the economy. A comparative analysis of the three methods using the adjusted R2 , Mean Square Error and Root Mean Error, as the statistics criteria, revealed that the result obtained from the Ridge Regression gave the outstanding performance as compared with the other two techniques. On the overall, it was found that the Ridge Regression performed best, followed by Principal Component Regression, while Latent Root Regression performed least.

    KEYWORDS:

    Multicollinearity, Ordinary Least Squares, Principal Component Regression, Latent Root Regression and Ridge Regression

    » Received: 01 July 2017
    » Accepted: 31 August 2017

    48 - 55

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    » Two-Phase Sampling for Stratification: Application to Software Industry

    » D. A. Agunbiade, S. O. Folorunso, K.-K. A. Abdullah and P. I. Ogunyinka

    ABSTRACT:

    Many authors have applied Two-Phase Sampling for Stratification (TFSS) to different areas of specialization. It was observed that such application is yet to be extended to the software industry. This research applied TFSS to the comparison of the two software types, Free and Open Source Software (FOSS) and Proprietary Software (PS). The estimated FOSS mean (4.5749) compared to PS mean (3.6390) revealed that FOSS is more rated than PS. The minimum estimated variance in FOSS (0.0046) over PS (0.0484) showed that FOSS is efficient than PS. The relative efficiency further confirmed that FOSS is 1052.17% efficient over PS. FOSS user rating has higher precision with Coefficient of Variation (CV) of 0.0148 as against PS user rating CV of 0.0605. It was, finally, concluded that FOSS is efficiently rated than PS by the software users.

    KEYWORDS:

    Two-phase Sampling for Stratification, User rating, Free-and-Open-Source Software, Proprietary Software

    » Received: 11 July 2017
    » Accepted: 31 August 2017

    56 - 60

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    » A Comparative Survey of DTW And HMM using Hausa Isolated Digits Recognition in Human Computer Interaction System

    » Yakubu A. Ibrahim and Tunji S. Ibiyemi

    ABSTRACT:

    Speech Recognition is a vital part of different computer-based applications in communication and security systems. However, there has been very little research in the aspect of speech Human Computer Interaction system for African languages such as Hausa, hence, the need to extend the research in order to bring in, the different systems based on speech recognition. Also, Hausa is an important ethnic tribe of lingua franca in both west and central Africa countries. Isolated word recognition is an easy speech type because it demands the user to pause between each word. In this study, the two algorithms that were used to implement a system of Recognition of Hausa isolated digits are Dynamic Time Warping and Hidden Markov Model. To perform the recognition efficiently, speech endpoint, framing blocking, speech normalization, vector quantization and Mel Frequency Cepstral Coefficient techniques were used to process the speech. The accuracy of about 94% was obtained for recognition with HMM-based system. In a very noisy environment, the performance of the two techniques is bad but the pattern matching using HMM is better than the pattern matching using DTW.

    KEYWORDS:

    DTW, Hausa Language, HMM, Speech Recognition, MFCC.

    » Received: 9 June 2017
    » Accepted: 31 August 2017

    61 - 67

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    » Expert System for Lassa Fever Diagnosis using Rule Based Approach

    » Hambali Moshood Abiola, Akinyemi Adesina Alaba and Luka Joy D.

    ABSTRACT:

    Lassa fever is an acute viral haemorrhagic fever caused by the Lassa virus and first discovered in 1969 in Lassa, a town in Borno State, Nigeria though it has been in existence since 1950s. Lassa virus belong to a member of the Arenaviridae family, a single stranded Ribonucleic Acid virus (RNA), has characteristic similar to Ebola virus. Lassa fever has killed thousands of people in West Africa, most especially in Nigeria, many of whose lives could have been saved if rapid diagnostic test was available; people who could have received treatment early and also who could have been isolated early enough to reduce spread of Lassa fever. Recently many people have died in the rural areas due to late detection or delay access to proper medical attention. This is due to the fact that most medical centres equipped with handling Lassa fever cases are situated far away from the rural communities. Hence, it would be of great necessity to provide a computerized system that will provide a complementary medical service where the experts are not sufficient. Therefore, in this paper, a rule-based medical expert system is developed and tested to address the various challenges of the traditional method of diagnosing Lassa fever. This research work tried to replace the manual method of diagnosing the Lassa fever by Medical Expert, with an Expert System (ES) which is capable of correcting all the limitations associated with the manual method.

    KEYWORDS:

    Expert System, Artificial Intelligence, Lassa Fever, Rule Based Expert System, Medical Expert System, Viral Hemorrhagic Fever.

    » Received: 24 April 2017
    » Accepted: 29 October 2017

    68 - 74

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    » A Construction and Representation of some Variable Length Codes

    » Nacer Ghadbane

    ABSTRACT:

    Let Σ be an alphabet. A subset X of the free monoid Σ* is a code over Σ if for all m, n ≥ 1 and x1, ..., xn, y1, ...ym ∈ X, the condition: x1 ... xn = y1 ... ym implies n = m and xi = yi for i=1, ...,n. In other words, a set X is a code if any word in X+ can be written uniquely as a product of words in X. It is not always easy to verify a given set of words is a code. In this paper, we give the construction and representation by deterministic finite automata of some variable length codes.

    KEYWORDS:

    Words and languages, the free monoid and relatives, morphisme of monoids, deterministic finite automata.

    » Received: 24 July 2017
    » Accepted: 29 October 2017

    75 - 78

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    » Structural Elucidation of Guaiane Sesquiterpenes from 13C Data using Generalized Regression Neural Network (GRNN) and Scatter Plots Methods

    » Taye T. Alawode and Kehinde O. Alawode

    ABSTRACT:

    This study seeks to elucidate of structures of unknown Guaiane sesquiterpenes from their 13C chemical shift values using Generalized Regression Neural Network (GRNN) and scatter plot methods. The 13C values for each of the fifteen (15) positions of the skeletons of the Guaiane sesquiterpenes were predicted using GRNN. From these predicted values, the substituents attached to each of the positions were predicted using GRNN and Scatter Plot methods. In predicting the skeletal 13C values, the 13C data of 116 Guaiane sesquiterpenes were used as input to GRNN while their corresponding data were used as the target data. The network was trained and simulated using twenty-five (25) test compounds. The best results were obtained at a spread constant of 5.0. In predicting the substituents on each position on the skeleton using the GRNN approach, the predicted 13C skeletal values of the test compounds were simulated following training of the GRNN using skeletal data of the 116 compounds as input data and their corresponding substituents (given codes) as the target data. The best results were obtained at a spread constant of 5.0. In the Scatter Plots method, graphs of codes of substituents for the 116 guaiane sesquiterpenes were plotted against the corresponding 13C chemical shift values of the skeletal Carbon to which they were attached. This gave the range of values over which each substituent may be obtained. The most likely substituent(s) for each position were selected. The degree of recognition of the test compounds (from both methods) ranged between 46.67 and 100%. Both methods gave similar recognition rates for the test compounds. GRNN and Scatter plots demonstrated great potential for use in the structural elucidation of unknown compounds from 13C values.

    KEYWORDS:

    GRNN, Scatter plots, structural elucidation, 13C, Guaiane sesquiterpenes.

    » Received: 15 July 2017
    » Accepted: 30 October 2017

    79 - 88

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    » Stability analysis of Mother–to–Child Transmission of HIV/AIDS Dynamic Model with Treatment

    » Bashiru Kehinde Adekunle, Fasoranbaku A.O., Adebimpe Olukayode and Ojurongbe T.A.

    ABSTRACT:

    A Mathematical Model of HIV/AIDS with mother – to – child transmission in the presence of treatment was examine in this paper, it ascertain the impact of treated individuals on the transmission dynamics of HIV/AIDS. Equilibrium points of the model system were found, stability analysis and numerical simulation was carried out. The result show that with treatment, the measure of the effect of health policies is realistic and control rate of mother – to – child is effective.

    KEYWORDS:

    HIV Transmission, ARVs, Compartmental model, stability, equilibrium points and Treatment.

    » Received: 26 July 2017
    » Accepted: 29 October 2017

    89 - 96

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    » Modeling Claims of Oil & Gas Nigeria Insurance Class of Business with Extreme Value Theory

    » Agunbiade D.A. and Adesina O.S.

    ABSTRACT:

    Oil and gas sector has been faced with huge losses in Nigeria as a result; insurance companies pay high premium due to these loses and Extreme Value Theory (EVT) is found to be suitable in modeling the extreme losses. Claims resulting from Nigeria Oil, and Gas insurance class of business for five insurance companies were modeled with EVT to estimate Value-at-Risk (VaR), where VaR measures the minimal anticipated loss over a period with a given probability and under exceptional market conditions. The mean excess plot was obtained which helps in determining the threshold value to be chosen and gives the shape of the distribution in the tail. Q-Q plot being linear and curved tail plots reveals that parametric model fits the data well. VaR based on EVT-Generalized Parameter (GPD) was carried using the chosen thresholds at 5% confidence interval. Results obtained were compared with VaR based on Historical and Gaussian method; it was established that Extreme VaR is most suitable to calculate VaR as against the Historical and Gaussian method.

    KEYWORDS:

    Extreme Value Theory, Value-at-Risk, GPD model, Peak-Over-threshold, Insurance.

    » Received: 13 September 2017
    » Accepted: 5 November 2017

    97 - 104

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    » Derivations for the Families of Generalized Distributions

    » Ifeyinwa Vivian Omekam and Adebowale Olusola Adejumo

    ABSTRACT:

    Generalization of distributions is usually motivated by limitations in characteristics of existing distributions so as to introduce more flexibility and improve goodness of fit. This is done by parameter induction into an existing distribution and therefore remains an approach to generalizing distributions. In this article, families of generalized distributions are generated by sequential application of methods in permutations of five distinct parameter induction methods: Lehmann Alternative 1 (LA1); Lehmann Alternative 2 (LA2); Marshal and Olkin Method (M-OM); α-Power Transformation (APT); and Power Transformation Method (PTM). This is done by taken two methods at a time. Sixteen distinct families of generalized distributions were generated. Some of the families of generalized distributions obtained are already in existence while several others are entirely new.

    KEYWORDS:

    Generalized distributions; Lehmann Alternatives; α-Power Transformation Method; Power Transformation Method; Marshall and Olkin Method.

    » Received: 6 August 2017
    » Accepted: 5 November 2017

    105 - 114

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    » Pattern Popularity in Γ1 − Non Deranged Permutations: An Algebraic and Algorithmic Approach

    » K. O. Aremu, A. H. Ibrahim, S. Buoro and F. A. Akinola

    ABSTRACT:

    Given a permutation pattern say τ = τ1 ... τk ∈ Sk and permutation ω = ω1 ... ωn ∈ S, we say that ω contains the pattern τ if there exist 1 ≤ i1 < ... < ik ≤ n such that red(ωi1 ... ωik) = τ. Each subsequence in ω is known as an occurrence of the pattern ω. Conversely, if there exists no occurrence of τ in ω, then we say that the permutation ω avoids the pattern τ. The popularity of a pattern τ is the total number of copies of τ within all permutations of a set. In this work, we address popularity of length-3 patterns in Γ1 - non deranged permutations in two approaches; algebraically and algorithmically. We first establish algebraically that pattern τ1 is the most popular and pattern τ3, τ4 and τ5 are equipopular in GΓ1p. We further provide efficient algorithms that also report same results on popularity and equipopularity of patterns of length-3 in GΓ1p as obtained by the algebraic approach.

    KEYWORDS:

    Permutation, Pattern, Popularity, Equipopularity, Sorting.

    » Received: 14 September 2017
    » Accepted: 10 November 2017

    115 - 122

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    » Efficiency Of Audu & Adewara (2017) Two-Phase Factor-Type Estimators With Two Auxiliary Variables In Sample Survey

    » A. Audu and A. A. Adewara

    ABSTRACT:

    In this paper, efficiency of Audu & Adewara (2017) two-phase factor-type estimators with two auxiliary variables for estimating finite population mean were examined using simulation. These estimators were obtained by incorporating some known functions of auxiliary variables X and Z in some existing factor-type estimators. Bias and Mean square error (MSE) of these estimators, ӯFTAAß1(d) and ӯFTAAß2(d) were obtained using tailor’s series expansion. Audu & Adewara (2017) revealed that although ӯFTAAß1(d) and ӯFTAAß2(d), have minimum MSE and high PRE than all other related existing factor-type estimators considered using three life dataset but of these two, which is more efficient and most preferred. The simulation results obtained in this study revealed that ӯFTAAß2(d) is more efficient than ӯFTAAß1(d) and hence, most preferred.

    KEYWORDS:

    Factor-type estimator, Two-phase sampling, Mean square error (MSE), Efficiency.Permutation, Pattern, Popularity, Equipopularity, Sorting.

    » Received: 12 July 2017
    » Accepted: 30 September 2017

    123 - 127

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    » Construction Of A Broyden-Like Method For Nonlinear Systems Of Equations

    » I. A. Osinuga and S. O. Yusuff

    ABSTRACT:

    Broyden-like methods (or hybrid Broyden methods) are one of the efficient modifications of the classical Broyden method proposed to solve nonlinear systems of equations and to overcome the deficiencies of the classical Newton method. In this work, a variant of the Broyden-like method is proposed using the weighted combination of the Trapezoidal, Simpson and Midpoint quadrature rules. Hence a new hybrid Broyden method known as TSMM has been created based on these rules. The numerical tests confirm that TSMM is promising when subjected to comparison with other Broyden-like methods.

    KEYWORDS:

    Broyden method, quadrature formula, predictor corrector, nonlinear systems, convergence, numerical examples.

    » Received: 30 September 2017
    » Accepted: 10 November 2017

    128 - 135

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    » A Spatial Analysis of International World Exchange using Complex Networks Analysis

    » Renata-Graziela Boar, Alexandra Fortiș, Alexandru Iovanovici and Horia Ciocârlie

    ABSTRACT:

    Modern economies are highly interconnected systems dominated by financial exchange. We propose a novel approach of analyzing the structure of the world financial markets by applying methodologies from the field of complex network analysis on a data set comprising he evolution of exchange rates on 23 major currencies over a time span of 14 years. Interesting economical insight is given based only on the topological properties of the correlation network which validate our methodology.

    KEYWORDS:

    econometrics, graphs, scale free networks, currency, exchange rate, community structure, correlation.

    » Received: 01 November 2017
    » Accepted: 13 December 2017

    136 - 142

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