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Ferroresonance is a nonlinear oscillatory phenomenon that occurs under certain conditions. This investigation use an indicator of ferroresonance based on voltage for damping of dangerous overvoltages in coupling capacitor voltage transformers (CCVT). This paper investigates ferroresonance voltage for determination technical requirements of the ferroresonance suppression circuit (FSC) for detection and suppression of ferroresonance. In this technique, by using a back-to-back gated thyristor circuit, a damping resistance is switched to secondary side of the system transformer during dangerous oscillations. The control technique proposed in this paper is a “novel but classic” technique. The prediction of ferroresonance is achieved by detailed modeling using a digital computer transient analysis program such as the EMTP.

This work highlights the interactions between fungus-growing termites (Isoptera, Termitidae), and mound building components. As major eco-engineers in tropical ecosystems, termites create biogenic structures with galleries, sheeting’s, fungus-comb chambers where the exosymbiotic interaction between termites and the fungus is well documented. Odontotermes spp. a fungus cultivator build mounds of different dimension that strongly influence the physical and chemical properties of soils there by clay mineralogy and SOM gets altered. In dry land ecosystems, termite mounds are often hotspots of primary production.

Currently, Ministry of Information, Communication and Technology in Thailand has focused on information and communication technology (ICT) to provide innovation solutions for socio-economic growth. The best concept for ICT Reform is that the Thai government should not dominate the role of providing ICT services, but they should be run more efficiently by private companies. Rather, the role of the government should be to be responsible for planning, structuring and regulation, whilst the private sector may be responsible for management, investment, construction and finance. The transfer of responsibility to the private sector and the introduction of competition should be accomplished through some transparent arrangements including management contracts, capital leases, concessions, sale of assets and rights to operate (Best Practices for Telecommunications Reform, 2002). However, there exist difficulties when the government has to formulate the ICT policy. The policymakers are often unfamiliar with the technologies that they are harnessing for the national development. This article explores the national ICT development models employed in different countries which exhibit some similarities and differences. In overall, the ICT policy is not only the direction about developing the ICT industry or sector of the economy but also encompasses the use of ICTs to engender economic, social, and political growth.

This paper discusses public policy making in Tanzania. Using documentary analysis, it attempts to find out whether the problems that were observed by Goran Hyden in1984 have so far been solved by policy makers. A point of reference is made to the fact that Hyden’s observation was made during the time in which Tanzania was under state controlled economy. With the country’s adoption of liberalization policies which Ndumbaro (1994) describes as the era of power shift in policy making from the state to donors, it is imperative to see whether this has affected policy making in the country. The paper concludes that although donors’ influence in policy making has continued to increase, there is no significant improvement in addressing policy-making problems that were noted by Hyden. Most of the policies continue to be made without adequate information, in which also the past does not seem to be of great use in shaping new policies. As a result, policy makers continue to be driven by a desire to do everything at the same time, which in turn increases the burden to policy implementers.

The freeze drying behaviour of local cheese was modeled using conservation laws of mass and energy balances such as Fick’s law of mass transfer, Fourier’s law of heat conduction and the Ideal gas equation. The three models developed and simulated are the drying rate, the moisture content and the energy balance models. Three different samples of cheese labeled A, B and C obtained from Bida, Suleja and Kontagora respectively all in Niger State of Nigeria were used to investigate the drying characteristics of local cheese. The analysis of the moisture contents showed that the moisture contents decreased with drying time and that the final moisture content at any time depends on the initial moisture content. Sample A with initial moisture content of 0.0124 kg has a final moisture content of 0.00097kg after 5 hours of drying, while samples B and C with initial moisture contents of 0.009kg and 0.0104kghave their final moisture contents of 0.00001kg and 0.00010kg respectively at the end of 5 hours. When the effect of temperature on moisture loss was studied, it was observed that the moisture loss increased as the freeze drying temperature was increased from 278 to 298K. Results also revealed that moisture loss depends on the initial moisture contents of samples. For this investigation, Samples A, Band C with initial moisture contents of 0.0124kg, 0.0138kg and 0.0104kg have moisture losses of 0.00420kg, 0.00440kg and 0.00363kg respectively at the highest freeze drying temperature of 298K. When the drying rates of samples was investigated, it was found that the drying rates decreased as the moisture contents decreased and which is also a function of the initial moisture contents of samples. The validation of the model was done by carrying out statistical precision analysis which compared the experimental results with those of the output of the models. From the results, the drying rate model showed 75 % agreement with the experimental results (i.e R2 value of 0.75), with a standard error of 3.27X10-5 and a variance of 5.37X10-8, the moisture content model interprets about 98.44 % of the experimental results with a standard error of 7.04X10-4 and the variance of 2.79X10-6, while the energy balance model showed about 99.0 % agreement with the experimental results with a standard error of 2.16X10-5 and a variance of 3.32X10-7.

Many researchers have carried out research on students’ academic performances in the University system, but there is dearth of information about models which focus on the relationship between students pre and post admission performances. This paper was therefore designed to model relationship between students’ pre and post admission performances. Information on pre admission performances (Olevel, Jamb and Post-Jamb results) and post-admission performances (100L – 400L results) of students’ in Statistics Department, Federal University of Agriculture, Abeokuta, Ogun State, Nigeria was collected from students’ file. Correlation matrix and Canonical Correlation analysis were used to know the degree of relationship that exists between the pre and post admission performances. The principal component analysis was employed to reduce the multidimensional data. Scree plot was used to determine the spread of the trend of the components and bi plot was used to determine the degree of closeness of the students’ pre and post admission performances. There is no relationship between pre and post admission performances. Also, no strong relationship among pre admission performances, while the relationship among post admission performances is very high. Post admission performances are highly related to students’ CGPA. The proportion of variance accounted for by the first, second and third principal Components are 50.7542%, 16.5712% and 15.6224% respectively with cumulative proportion of 82.95%. The first, second and third components are chosen. The seven components were reduced to three. Post admission performances are closely related and stand as the determinant of students’ class of degree.

We are very happy to announce that from 4th January 2013, Mr.Neeraj Jindal has joined the team of Elixir Editorial Advisory Board. He will carry a special responsibility for dealing with manuscripts based on Electrical Engineering. Mr.Neeraj Jindal is currently working as Assistant Professor (ECE) Chartered Institute of Technology, Mount Abu (Rajasthan). The appointment of Mr.Neeraj Jindal as member Editorial Advisory Board strengthens the links and will make it easier for prospective authors to establish contact with the journal. Please send any expressions of interest to chiefeditor@elixirjournal.org. Sincerely Editor-in-Chief

This paper presents the new trends in code division multiple access techniques known as Optical CDMA Technology. I highlight those trends and features that are believed to be essential to the successful introduction of various OCDMA techniques in communication systems and data networks in near future. In particular, i elaborate on enabling technologies that are needed prior to full scale consideration of OCDMA in communication systems. I extend my discussion to various data network. It is believed that OCDMA once fully developed and matured will be an inseparable part of advanced optical communication systems and networks due to its various desirable features and functionalities, in not so distant future. Optical Code Division Multiple Access (OCDMA) is an optical processing system which allows multiple users to share the same bandwidth simultaneously without interfering with each other using unique optical codes. In this paper we present an in depth review on the new trends and the directions taken by the researchers worldwide in Optical Code Division Multiple Access (OCDMA) systems.

This study evaluated the presence of ochratoxin producing fungi and levels of ochratoxin A contamination in the most popular cassava food product (garri) in West Africa circulating in Ogun State, Nigeria. Results obtained revealed that the rate of total filamentous fungal contamination in all the sampled zones of Ogun State, Nigeria were not statistically significant (F= 0.327, P>0.05). For the black Aspergilli, the maximum contamination rate was 4.2 x 107 CFug-1 for a sample in Egba zone while the minimum concentration of 2.5x102 CFug-1 was obtained in a particular market in Remo zone. It was noted, that Aspergillus niger and Aspergillus carbonarius have the highest isolation rate of 21(24%) among the isolated filamentous fungi (F= 88.167, p< 0.05). 918 (92%) of the total samples of 1000 examined, contained detectable levels of OTA while samples from egba region have highest contamination rate (Fvalue = 3.504, P<0.005). These detectable levels found in our study satisfies the 0-5.0ppb recommended by the Codex Alimentarius Commission (1997). It can be concluded, that garri found in Ogun State are variously contaminated by different filamentous fungi, however black aspergilli remain the main ochratoxigenic moulds present in this staple food.

In this paper, we introduce and study some new separation axioms using the (1, 2)*-?gb-open sets in bitopological spaces.