Open Access Short Research Article

Lung Cancer Mortality from Exposure to Indoor Radon (222Rn) in Mexico

A. Ángeles, G. Espinosa

Advances in Research, Page 1-9
DOI: 10.9734/AIR/2015/17736

To evaluate lung cancer mortality in Mexico in the year 2012 attributable to exposure to the radioactive gas radon. Values of mortality from exposure to indoor 222Rn are obtained by the application of a model of excess of relative risk for the average indoor 222Rn concentration in Mexico taking into account values of lung cancer mortality statistics in Mexican population and smoking habits.  

Lung cancer Mortality from exposure to 222Rn is estimated, for Mexican Republic in year 2012, with an exposure to indoor 222Rn for the last 35 years before 2012. The excess relative risk (ERR) model published in the BEIR VI report and modified by the USEPA was used with the Mexican population and lung cancer mortality rate data for both genders from the year 2012.

According to official statistics there were a total of 6,547 deaths from lung cancer in Mexico in 2012, of which 4,147 were of males and 2,400 of females. The general mortality rate was 5.67; the mortality rates for males and females were 7.4 and 4.1 respectively. The countrywide average indoor radon concentration was estimated to be 83.3 Bq/m3. By calculating the excess relative risk (ERR) using the relevant mortality, demographic and smoking prevalence data, we were able to estimate that 3,041 male lung cancer deaths (73.3%) were attributable to causes other than radon exposure and that the remaining 1,106 lung cancer deaths (26.7%) were attributable to radon exposure. We estimate that 1,641 female lung cancer deaths (72.6%) were attributable to causes other than radon exposure and 619 (27.4%) were attributable to radon exposure. Lung Cancer Mortality rate from exposure to indoor 222Rn in Mexican population is smaller than UK, American and Canadian population although the average value of 222Rn  in Mexico is larger than those countries, due to the small baseline of lung cancer in Mexican population.


Open Access Policy Article

The Multiple Streams Framework and the 1996 and 2007 Educational Reforms in Ghana

Antwi Boasiako, Bossman E. Asare

Advances in Research, Page 1-15
DOI: 10.9734/AIR/2015/17697

The paper examines the formulation of the Free Compulsory Universal Basic Education policy and the Kuffour-led education reforms in the education system of Ghana in 1996 and 2007 respectively. The study is undertaken through the lens of the Multiple Streams Framework (MSF) developed by John Kingdon in 1984 to underscore how different factors or streams collectively influence the adoption of certain policies. The paper argues that far more than mere pursuit of party manifesto promises, broad problem, policy and political occurrences conspired to call forth the reforms. By so doing, the paper puts the theoretical assumptions of MSF to test and finds that though developed within the context of the American democratic system to explain policymaking, the MSF finds utility in the Ghanaian context as well, making its postulations generalizable.


Open Access Original Research Article

Oscillation Analysis for Longitudinal Dynamics of a Fixed-Wing UAV Using PID Control Design

B. K. Aliyu, C. A. Osheku, P. N. Okeke, F. E. Opara, B. I. Okere

Advances in Research, Page 1-13
DOI: 10.9734/AIR/2015/18334

A longitudinally disturbed motion of a UAV after an arbitrary initial disturbance consists normally of two oscillatory modes: the short-period oscillation and the phugoid oscillation.The typical longitudinal model of a UAV in state-space can be separated into short-period mode and phugoid period mode equations of motion. In this study, we choose to investigate the dynamic characteristics of the longitudinal dynamic equation of a mini-UAV and its reduced forms popularly known as short-period and phugoid period modes. This is necessary to establish a basis for plant selection during PID autopilot design. The short and phugoid period oscillations modes are sieved from the longitudinal dynamic equation and carry the same eigenvalues of the longitudinal model, but they still differ. Firstly, the three systems have different step response trajectories due to their different DC gain values. Secondly, the variables that constitute the short-period and phugoid mode dynamic equations can be identified by their settling time after designing PID controllers. State-space model of the longitudinal dynamics, phugoid mode and short period dynamics of a UAV can be transformed into equivalent transfer functions. These transfer functions are then used in the design of Proportional, Integral and Derivative (PID) controllers. Hence, the phugoid mode variables are the system variables in the longitudinal dynamic model with the longest settling time. The short period mode variables are the longitudinal system variables with the shortest settling time. Synthesis and simulation were done in MATLAB/Simulink. Also, from simulation results, plant for autopilot design could be selected based on the system with smallest rise time.


Open Access Original Research Article

Computer Aided System for UNI-functional Job Shop Machine Selection Based on Production Cost and Technology Advancement

Basil O. Akinnuli, Yakubu A. Jimoh, Adeyemi A. Aderoba

Advances in Research, Page 1-12
DOI: 10.9734/AIR/2015/15691

When it comes to processing of material (job processing) which has alternative means of producing the required product(s), there are machines competing for the job(s) and machine that will do the job economically at low cost out of the existing alternatives must be wisely selected. This study hence developed decision rules models for selecting machine that will give optimum production cost considering alternatives available based on technology advancement of the machines. The specifications of the machines used are hereby stated: swing of machines is 406 mm, distance between centres is 762 mm, speed of electric motor is 1800 rpm while the power of the motor is 15 Horse power. The material machined was mild steel, while the cutting tools used was HIGH Speed Steel (HSS). The depth of cut for rough cutting was 3 mm the speed is of 12 m/min while the depth of cut for finish cutting was 0.4 mm at the speed of 240 m/min. The strategic decisions used are: fixed cost, variable cost, and break-even point between alternatives. Computer software was developed using Microsoft Visual Basic programming language. These models and the developed software were tested using Don Bosco Technical College, Ondo. Nigeria as case study where the machines are available with same specification but difference in technology (manual, semi-automatic and automatic). The results were highly promising for decision making and will find its applications in Job-shop Industries, Institutions with production basis, mechanical and manufacturing workshops that production cost as well as technology advancement for selection of machines affects their production in both developed and developing countries.


Open Access Original Research Article

Flexural Behavior of Composite Slab

Khaled M. El-Sayed, Nader Nabih, Ayat M. Taha

Advances in Research, Page 1-12
DOI: 10.9734/AIR/2015/18847

Aims: This study deals with the enhancement of the longitudinal shear interaction at the concrete-profiled steel sheeting interface of composite slab by using shear connectors. The push out and flexural tests are carried out with the same shear connection details.

Place and Duration of Study: The test is carried out in RC laboratory at Faculty of Engineering in Benha, Benha University, Egypt, between May 2014 and March 2015.

Methodology: Fourteen push out specimens with different configurations were built in, of which five specimens with steel deck thickness of 0.7 mm and nine specimens with steel deck thickness of    1.2 mm. For each profiled steel sheeting thickness one specimen is assigned as a control specimen and the other specimens were enhanced with different types of shear connectors such as self-drilling screws with different length and spacing, cold formed members with different shapes (U&C) and different spacing. Eleven large scale specimens with different configurations were prepared. Four specimens were prepared with profiled steel sheeting of 0.7 mm thickness and seven specimens with profiled steel sheeting thickness of 1.2 mm. One control specimen for each profiled steel sheeting thickness was also prepared. The other specimens were enhanced with different types of shear connectors: self-drilling screws with different length and spacing and cold formed members with different shapes (U&C) with different spacing.

Results: The test results show that the failure mode of composite slab can be improved to ductile type and the load carrying capacity can be increased by the presence of the shear connectors. The load performance of the slab is also affected by changing the profiled steel sheeting thickness.


Open Access Original Research Article

The Thermal Analysis of Fuel Fired Crucible Furnace Using Autodesk Inventor Simulation Software

A. A. Abioye, P. O. Atanda, O. F. Kolawole, O. E. Olorunniwo, A. R. Adetunji, O. P. Abioye, K. J. Akinluwade

Advances in Research, Page 1-7
DOI: 10.9734/AIR/2015/16235

The reasons for failure of locally made furnace in the foundries were as a result of cycles of operating temperatures that they were subjected to, which caused thermal stress and strain on the furnaces. This paper studied the simulation of thermal analysis of Fuel fired Crucible Furnace to predict the effect of thermal stress and strain on it.


Open Access Original Research Article

The Influence of Homogenization Treatment on Aging Response of 6063 Aluminium Alloy

D. A. Isadare, M. O. Adeoye, A. R. Adetunji, K. M. Oluwasegun, K. J. Akinluwade

Advances in Research, Page 1-11
DOI: 10.9734/AIR/2015/18166

This paper reports the effect of homogenization treatment on T6 tempering of 6063 aluminium alloy. Wrought 6063 aluminium sample was machined into tensile and impact tests specimens. Samples were also cut for hardness and metallographic works. These samples were divided into two groups; group I samples were homogenised at 570ºC for 2, 2.5, 3 and 3.5 hours respectively prior to T6 temper while group II samples were T6 tempered without prior homogenization. The heat treated samples was subjected to tensile, impact and hardness tests and the evolved microstructures was characterised using a scanning electron microscope equipped with energy dispersive spectrometer. The results show improvement in the mechanical properties for those samples homogenized prior to aging as compared to conventionally aged samples and there was also an unusual combination of mechanical properties in terms of ductility, toughness and strength. The resulting microstructures shows the presence of rod-like phases in the as-received and T6 tempered samples while group II samples contain spherical precipitates. The overall result showed that prior homogenization can prevent the usual concomitant decrease in ductility and toughness of T6 tempered 6063 aluminium alloy.