Archives-January 2012

In this paper, we consider a deterministic mathematical model for the transmission dynamics of an infectious disease in a community. Although, the equilibria of the model could not be expressed analytically, their existence and the threshold conditions for their stability are theoretically and numerically investigated. We analyzed the stability of the model using the linearization techniques via the Jacobian matrix approach and the Routh-Hurwitz stability criteria to determine the equilibria for the model. The basic reproductive number of the model was determined using the next generation matrix operator. Their numerical results were shown in graphical forms using some hypothetical values for the parameters used in the model. It was shown graphically that the mathematical model produced asymptotically stable population when the parameter values are perturbed to a certain degree.

The seed of Syzygium aromaticum was analysed for its proximate and mineral elements constituents, the chemical characteristics and fatty acids profile of the seed oil were also investigated. Results revealed that the seed contain (g/100g) moisture (23.4 ± 1.25), ash (9.10 ± 0.55), crude fibre (10.65± 0.21), crude fat (18.90± 0.04), crude protein (7.00± 0.01) and carbohydrate (30.95 ± 2.17), gross calorific value of 321.9 K cal/g. The quantities of nutritive elements in mg/kg were Mg (1259.50 ± 30.10); Ca (782.40 ± 10.65); Fe (710.65 ± 5.20), Na (2.56 ± 0.02) and K (2.69 ± 0.03). The chemical properties of the seed oil revealed iodine value of 122.08 ± 1.01 mg/g oil, peroxide value of 6.00 ± 0.02Meq/kg and saponification value of 187.00 ± 1.42 mg KOH/g. Eleven fatty acids were identified in the seed oil by GC, total saturated fatty acids was 61.37 %, alpha linoleic acid was 19.09 % and docosahexaenoic acid was present at 2.94%. The seed could be explored as feed supplement and its oil considered for industrial applications.

This study looks at the effect of the sea water is having on the Densu delta wetland. The objective of this work is to assess the hydro- chemical dynamics of the surface water from the Densu delta using hydro chemical parameters, stable isotopes- oxygen-18 and deuterium and also asses the quality of the surface water for purposes like irrigation using SAR, %Sodium and other modules. Samples of surface water were taken for physico-chemical analysis. The samples were analysed for physical and chemical parameters and the stable isotopes (18 O and D2O). The results from the stable isotopes have shown that the quality of the surface water is being affected by slight mixing with sea water. From the SAR calculation, 62% and 38% of the water was within the excellent and good category respectively and none were within the doubtful and unsuitable category respectively. Calculation of % sodium showed that about 5 out of 8 samples have high sodium percent (above 60%) and are not suitable for irrigation purposes as per classification of Eaton 1950. From the Richards diagram, approximately 12.5% fall within good category; 75% in the category of doubtful; 12.5% within unsuitable category. Approximately 50% of the samples were found to be good by RSC index; 37% fall within the doubtful category and 13% unsuitable. A high percentage was within permissible ranges for TDS. The results suggest that generally water samples are suitable for domestic and irrigation purposes under normal temperature and pH condition.

In this study, two different type of Artificial Neural Networks (ANNs) were analyzed in simulating the daily inflow into Taleghan reservoir in Iran. These types include: General Regression Neural Network with standardized inputs (GRNN1) and with non-standardized inputs (GRNN1), and Radial Basis Networks with standardized inputs (RBN1) and with non-standardized inputs (RBN2). An iterative algorithm was designed to assess different architecture of these models. Results revealed the potential of these models, as suitable tools for simulating the daily reservoir inflow. Also, it was concluded that multiday averaging can improve the simulation results considerably.

Teacher development has become a key concept in the field of education. Both pre-service and in-service teacher training are extremely crucial in the entire process of the development of a teacher as a professional. In-service training received due attention from the experts and educators in order to strengthen the base of pre-service training or lay a new foundation for those who have no formal training, and to follow up training needs as continuous teacher development. Education has been changing globally in order to meet the urgent demand of the society, economics, and science-technology. There has been a focus all over the world to develop the teachers of the institutions to meet the needs of the students, and institutional effectiveness leading to the national development. King Abdulaziz university (KAU) is one of those pioneering institutions in Saudi Arabia that has been taking the initiatives to equip its staff to raise them to the international standards (if required). Jeddah community college (JCC), being the part of KAU also realised the need of teacher development activities. Many training, pedagogic, and developmental activities took place in the past especially from 2007 till date. The present paper aims at exploring those training activities that were carried out at JCC in order to equip and update the skills of the target teachers. In this connection, many seminars, workshops, training sessions were organised by the JCC, and the teachers attended those programmes within the college, university, and even went abroad for a 2 week-intensive trainer’s training organised at Greenwich Community College, London, UK. The training course was sponsored by the university. It was expected that after such teacher development activities, the teacher preparedness will be enhanced, and the outcomes will be more beneficial for the students. As a matter of results, the present teaching at JCC is modern, novel, innovative, e-learning/online learning based and computer assisted which itself is one of the motivating factors, interesting for the learners, and needed for the ultimate human resource development.

Variation is an important mathematical physics method in mathematical physics problem. Many physical problems are always concerned with variation, and they can be solved by extremum of functional. We can obtain physical laws by way of variation calculus, such as the solution of problems of central field and electromagnetic field. By application of calculus of variation, the motion of matter can be unified.

The problem of capacitor allocation in electric distribution systems involves maximizing energy and peak power loss reductions by means of capacitors installation. This paper presents a novel approach using reinforcement learning (RL) algorithm to determine suitable candidates' nodes in a distribution system for capacitor placement. The problem formulation considers two distinct objectives related to total cost of power loss and total cost of capacitors including the purchase and installation costs. The proposed method of this article uses RL for sizing and placing of capacitors in radial distribution feeders. The proposed method has been implemented in a software package and its effectiveness has been verified through a 9-bus radial distribution feeder, 34-bus radial distribution feeder along with 33-bus and 66-bus distribution systems. A comparison has been done among the proposed method of this paper and similar methods in other research works that shows the effectiveness of the proposed method of this paper for solving optimum capacitor planning problem.

Regular environmental monitoring has being going on ever since the operation of the Ghana Research Reactor-1 (GHARR-1) to ensure both the safety of the workers in that they are not exposed to any harmful radiations and that equipment’s that are used are in good condition. The objective of this work is to know if the right procedures are being followed to ensure that the minimum radiation dose is not being exceeded as well as not exposing the public to any controlled sources. Moreover over the years there have been encroachers on the Ghana Atomic Energy Commission (GAEC) land and this work therefore seek to know the possible effects these radiations have on those people. From the results obtained 2008 had a range of (0.03-3.10)µSv/h, (0.04-2.71)µSv/h for 2009, (0.07-2.81)µSv/h for 2010 and 2011 also had a range of (0.05-5.64)µSv/h. Comparing to the recommend value (For the public the limit is 1 mSv in a year, or in special circumstances up to 5 mSv in a single year provided that the average dose over five consecutive years does not exceed 1 mSv per year), this shows that the radiations recorded are within the recommended value indicating that the right procedures are being followed. Suffice to say this more work has to be done to ensure that there is a sustainability in following procedures and that the encroachers too must be warned off to avoid any consequences in case there is unavoidable accidents in the near future

This study investigated the employee retention dependency on predictor variables like training program, incentive programme, co-worker social support, working hours and union representation. For this purpose data have collected from individuals in four banks and government employee who are living in government colonies in Pakistan. Total population was approximately 550 and sample size 226 has been used for collecting data. The regression test is used to check dependency of employee retention on predictor variables. the result of the study indicate that employee retention depend more on incentive program, union representation, co worker social support, and less on working hours and supervisory program. However incentive program is more significant predictor variable for employee retention than other variable.

This paper discusses the body of knowledge about Holonic Approach to theoretically demonstrate how Holonic Production System (HPS) can be a convincing choice to overcome the problems of traditional production systems’ architectures. Today, enterprises are trying to find ways to manage the growing environmental complexity that is well described by Complex Systems Theory (CST). After the focus on the main problem regarding environmental complexity, the Holonic system and the Holonic Production System will be analyzed. The paper will focus the potential of HPS to adapt and react to changes in the business environment whilst being able to maintain systemic synergies and coordination through the holonic structure where functional production units are simultaneously autonomous and cooperative.