Open Access Opinion Article

Pricing De Solla Price’s Circumvent

A. Victor Adedayo

Advances in Research, Page 488-492
DOI: 10.9734/AIR/2015/14630

Aims: This study examines the foundations of modern scientometrics as laid down by Derek De Solla Price who is reputed to be the founding father of scientometrics.

Methodology: A brief overview of the study of network structures was made. This was used to identify the onset of erroneous assumptions in the premise laid by De Solla Price. Established similarities between citations and voting was exploited and used to quantify the extent of the errors made in De Solla assumptions.

Conclusion: It was found out that the assumptions of De Solla Price are about 78% in error.

 

Open Access Original Research Article

Detection and Genetic Characterization of an Avipox Virus Isolate from Domestic Pigeon (Columba livia domestica) in Morogoro Region, Eastern Tanzania

S. N. Masola, A. Mzula, E. D. Mwega, C. J. Kasanga, P. N. Wambura

Advances in Research, Page 460-469
DOI: 10.9734/AIR/2015/13382

Aim: To determine molecular and evolutionary characteristics of a newly isolated Tanzanian isolate of pigeonpox virus (PGPV).

Study Design: Experimental.

Place and Duration of Study: Faculty of Veterinary Medicine, Sokoine University of Agriculture, Morogoro, Tanzania; between November 2011 and May 2014.

Methodology: Samples of cutaneous nodular lesions were collected from 17 pigeons suspected to have pigeonpox in Morogoro (n = 11), Pwani (n = 2) and Dar es Salaam (n = 4) regions; followed by virus isolation, and confirmation by amplification and sequencing of P4b gene. Further the sequence was phylogenetically analyzed for its evolutionary relationship with other related viruses.

Results: PGPV was detected in two samples, both from Morogoro region. Sequence analysis revealed that the Tanzanian PGPV isolate derived in this study was 90 – 99% identical to several avipoxvirus isolates from birds belonging to different species from several countries; for instance the Tanzanian PGPV isolate was 91% identical to each of the Tanzanian fowlpox virus isolates derived in the previous study, and 99% identical to all three PGPV isolates whose sequences were obtained in the GenBank i.e PGPV isolates from India (accession number DQ873811), Egypt (accession number JQ665840) and a PGPV (accession number AY530303) whose country of origin is unknown. Phylogenetic analysis revealed that the Tanzanian PGPV isolate belongs to clade A in subclade A2, sharing a recent common ancestor with members of subclade A3.  

Conclusion: Currently, pigeonpox virus is circulating in Morogoro region. The present study warrants the further surveillance/ molecular epidemiology of PGPV in Tanzania in a large-scale.  

 

Open Access Original Research Article

Investigation of Diagnostic Test Performance Using Receiver Operating Characteristic and Fundamental Concepts of Information Theory

Özlem Ege Oruç, Armağan Kanca

Advances in Research, Page 470-476
DOI: 10.9734/AIR/2015/13219

Aims: Receive Roperating Characteristic (ROC) curveanda fundamental concept of information theory is directly applicable to evaluation of diagnostic test performance. In this study,the performance of the two diagnosis tests on the field of rheumatic disorder is analyzed byusing receiver operating characteristic and fundamental concepts of information theory. The aims of this study to investigate which diagnosis  tests  has better performance and to demonstrate which test can be an alternative to gold standard test by carrying out ROC and fundamental concepts of information theory.

Study Design: ROC analysis and application of fundamentals concept of information theory (entropy, conditional entropy, mutual information).

Place and Duration of Study: Department of Statistics, between July 2012 and July 2013.

Methodology: Anti-Streptolysin O (ASO) is a value which is used to learn whether the patients have group “A” beta-hemolytic streptococcal infection which causes rheumatic disorder diseases. ASO values of 68 subjects who applied to Thoracic and Cardiovascular Surgery Training and Research Hospital in Istanbul for the diagnosis of rheumatic disorder were used. ASO values were evaluated according toTurbidimetric tests of two different firms. These tests were called as I. Turbidimetric test and II. Turbidimetric test. Both ROC and Information Theory analyses were applied to the data. Therefore, bothfirms’ Turbidimetric test diagnostic performances were evaluated and which diagnostic test had better performance was determined.

Results: According to ROC curve results, Area Under curve(AUC) is calculated 0.98 for I. Turbidimetric test and 0.90 for II. Turbidimetric test. On account of information theory analysis; the entropy value is the same but mutual information values are different. According to the result of mutual information, I. Turbidimetric test providesmore diagnostic information than II. Turbidimetric test. Therefore I. Turbidimetric test dominates II. Turbidimetric test. Based on these results, it can be verified that mutual information value is parallel to AUC value. Another result is found for threshold values of tests. According to results an alternative threshold values for tests can be obtained by using mutual information.

Conclusion: TheTurbidimetric tests’ performances are examined using ROC and information theory. With regard to ASO values, it is concluded that I. Turbidimetric test is more likely to show the similarity to Nefelometric test in comparison with II. Turbidimetric test. Using I. Turbidimetric test has financial benefits to clinicians, since it is less expensive in contrast with Nefelometric test.

 

Open Access Original Research Article

Comparative Design for Improved LQG Control of Longitudinal Flight Dynamics of a Fixed-Wing UAV

B. K. Aliyu, A. M. Chindo, A. O. Opasina, Alih Abdulrahaman

Advances in Research, Page 477-487
DOI: 10.9734/AIR/2015/14174

This paper explores the design, simulation and analysis of three novel Linear Quadratic Gaussian (LQG) control system for a Longitudinal dynamic of a fixed wing mini Unmanned Aerial Vehicle (UAV). Modelling results for the small UAV using Aircraft DIGITAL DATCOM® are presented. The novelty of the design is from the stand point of the Kalman Filter, with Kalman gain obtained from the solution to a Differential Riccati Equation (DRE) rather than the popular Algebraic Riccati Equation (ARE). The formulated DRE to the Kalman filter design is solved as an Initial Value Problem (IVP) in the MATLAB/Simulink® using explicit algorithm ode45. The algorithm converges to a solution of interest with 6671steps. Each step has a covariance matrix hence a different Kalman gain value as the solution tries to converge, after 10 seconds of simulation. Three of 6671 step values are selected based on the observed trajectory of the Kalman gain matrix and the time for the set-point tracking control of the pitch angle to reach a steady-state value. Three of these Kalman gains obtained were used in the design of the linear Kalman filter, which serves as the observer for the Linear Quadratic Regulator (LQR), hence the improved LQG controllers. Comparison is made between the three improved LQG controllers and the LQG controller on the bases of step response characteristics and robustness. Using the robustness properties of the Kalman filter as a benchmark, simulation result shows that all the three improved LQG controllers outperform the LQG.

 

Open Access Original Research Article

Does the Addition of a Marketing Intermediary Increase the Manufacturer's Profits?

Reut Gantz, Mor Levi, Elinor Idan, Kobi Idan, Amir Elalouf

Advances in Research, Page 493-501
DOI: 10.9734/AIR/2015/10742

This article will examine whether adding a marketing intermediary can increase a manufacturer's profits, as compared with marketing the product directly to the consumer. Previous studies suggest that cooperation between manufacturers and retailers provides both parties with benefits such as cost reduction, reduction of inventory levels and improved customer service, in addition to higher profits than each party would have achieved on its own. Clearly, the common interests of the two parties surpass the potential conflicts between the parties and these common interests should dictate the nature of the collaboration.

Herein, using a mathematical model, we show that under certain conditions a manufacturer of durable consumer goods in a vertically integrated supply chain can increase profits by decentralizing, i.e. adding a retail distribution channel. This result holds even if the retailer does not bring unique skills or knowledge to the relationship or if there is no competition in the product market. We deal with two problems simultaneously: The channel coordination problem and the Coase problem (although we focus on markets in which the manufacturer must sell products rather than lease them). We use a numerical example to demonstrate an application of our model and we offer directions for future research.

 

Open Access Original Research Article

Hybrid Particleboard from Wood and Non-Wood Species: Physical and Mechanical Properties as a Function of Particle Mixing Ratio

Md. Abu Wabaeid Hasan, Tania Islam, Khandkar- Siddikur Rahman, Sourav Bagchi Ratul, Md. Azharul Islam, Arifa Sharmin, Md. Nazrul Islam

Advances in Research, Page 502-511
DOI: 10.9734/AIR/2015/14229

Aims: In this paper three-layer hybrid particleboard was fabricated from kadam (Anthocephalus chinensis) and kenaf (Hibiscus cannabinus L.) as a function of particle mixing ratio based on oven dried weight.

Experimental: Three types of three-layer hybrid particleboards i.e., HBPB-A (Fine: kenaf; coarse: kadam), HBPB-B (Fine: kadam; coarse: kenaf), HBPB-C (kadam and kenaf mixed); and two types of control particleboard i.e., CPB-D (kadam) and CPB-E (kenaf) were fabricated with 10% urea formaldehyde resin. The effects of particle ratio on the physical and mechanical properties of new hybrid particleboards were investigated according to the procedure of ASTM D-1037 standard.

Results: It was found that the particle ratio within and/or between layers showed significant effects on the physical and mechanical properties of the hybrid particleboards. It was also observed that hybrid particleboard HBPB-C with the ratio of kadam: Kenaf(50:50) exhibited the highest mechanical properties i.e. modulus of elasticity and modulus of rupture and physical properties i.e. density, moisture content, water absorption and thickness swelling, compared to HBPB-A (kenaf: kadam-40:60) and HBPB-B (kadam: kenaf-40:60) hybrid particleboards. HBPB-C also showed higher physical and mechanical properties compared to the CPB-E, however, it was lower than the CPB-D.

Conclusion: The results confirmed that HBPB-C and HBPB-B particleboard met the minimum ANSI A208.1 requirements for physical and mechanical properties of M-3 grade particleboard. Thus, such kind of hybrid particleboard is technically feasible. 

 

Open Access Original Research Article

Two Approaches for Solving Non-linear Bi-level Programming Problem

Eghbal Hosseini, Isa Nakhai Kamalabadi

Advances in Research, Page 512-525
DOI: 10.9734/AIR/2015/14195

In the recent years, the bi-level programming problem (BLPP) is interested by many researchers and it is known as an tool to solve the real problems in several areas such as economic, traffic, finance, management, and so on. Also, it has been proven that the general BLPP is an NP-hard problem. In this paper, we attempt to develop two effective approaches, one based on approximate approach and the other based on the hybrid algorithm by combining the penalty function and the line search algorithm for solving the non-linear BLPP. In these approaches, by using the Karush-Kuhn-Tucker conditions the BLPP is converted to a non-smooth single problem, and then it is smoothed by Fischer-Burmeister functions. Finally, the smoothed problem is solved using both of the proposed approaches. The presented approaches achieve an efficient and feasible solution in an appropriate time which has been evaluated by comparing to references and test problems.