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INTEGRATED GEOPHYSICAL METHODS IN THE CHARACTERIZATION OF SUBSURFACE CONDITIONS OF LAPITE DUMPSITE IN IBADAN, SOUTHWESTERN NIGERIA
Get PDFGroundwater contamination within the vicinity of dumpsites has elicited public health concern in recent time. Studies have shown that contaminants may infiltrate into the groundwater through permeable soils, weathered and fractured bedrocks. Lapite village, underlain by Basement Complex rocks, hosts one of the largest and most active dumpsites in Ibadan. The dumpsite came into existence without prior hydrogeophysical evaluation of its suitability as a landfill site, especially its likely impacts on the surrounding groundwater. This study was designed to assess the suitability of the dumpsite for waste disposal by evaluating hydrogeophysical properties of rocks in the area. Geological field mapping was carried out around Lapite dumpsite to determine various rock types. Very Low Frequency-Electromagnetic (VLF-EM) measurements consisting of four transverses and sixty-one Vertical Electrical Soundings (VES, using Schlumberger array) were carried out along the 200.0 and 400.0 m of the dumpsite. Banded and migmatite gneisses were the underlying rocks in the area. The VLFEM pseudo-section showed high conductivity zones indicating the presence of fluid-filled fractures in the rocks. The VES geoelectric section revealed four layers namely, topsoil (33.6-973.7Ωm), lateritic sand (82.0-520.4Ωm), weathered layer (11.9-133.0Ωm) and fractured/fresh bedrock (387.0-3767.4Ωm) with thicknesses (m) of 0.1-2.8, 0.8-4.8, 1.2-49.2 and undeterminable respectively. The presence of fractured basement as indicated by VLF-EM pseudo-section and VES geoelectric section may act as a transmitting medium for leachate that may emanate from waste dump into the surrounding groundwater. Lapite dumpsite is located on weathered and fractured bedrocks and these may permits infiltration of contaminants into the surroundinggroundwater. Thus, the present condition of waste dumpsite is not suitable for an ideal waste dumpsite. 
EFFECTS OF NUTRIENTS AND CROPPING DENSITY ON CASSAVA FOLIAGE IN CASSAVA-GROUNDNUT INTERCROPPING
Get PDFThe study was aimed at evaluating the relative effects of nutrient sources, cropping density and intercropping on selected soil variables and cassava crop foliage attributes It was conducted at Teaching and Research Farm of the Delta State University, Abraka (latitude 50 46’ and longitude 60 5’) July 2008 to June 2009, in the humid rainforest zone of Southern Nigeria. The experimental design was a 4x3x3 factorial experiment in RCBD pattern using three replicates, consisting of four nutrient levels, three cropping densities and threecropping patterns. The 4 nutrient levels were zero application, 200kg NPKMg, 40 tons of water hyacinth/poultry manure-based vermicompost (VPM) and 40 tons of water hyacinth/cow dung-based vermicompost (VCD). The 3 cropping densities were 50,000, 100,000, and 200,000 plants ha-1, while the three cropping patterns were sole groundnut, sole cassava and cassava-groundnut intercrop. Rate of leaf formation, leaf area index and stay green core of cassava were significantly increased by vermicompost application. 
IMPROVEMENT OF MEDICATION DELIVERY TRICOPTER STABILITY USING ACKERMAN METHOD
Get PDFUnmanned aerial vehicles (UAVs) have been a subject of interest across many areas of study. Tricopter is a multirotor with three rotors in Y or T configuration for flight operations; capable of tilting with the aid of a servo motor. The study designed stability controller for a developed medication delivery tricopter to enhanced community-based healthcare system in Nigeria. The study adopted a control law based on Ackerman’s method to improve the tricopter’s settling time, maximum overshoot and damping factor; through a linearizedmathematical model. Desired poles were implemented in MATLAB simulink environment to design a suitable controller for the system in accordance with predefined parameters. The output revealed no overshoots along X and Y axes at settling time of 3s, but overshoot along Z axis by 50% at settling time of 2s. Conclusively, the steady state error was zero and it was observed that the medication delivery tricopter response was made stable with the aid of a controller. The result shows that the tricopter model can be made effectively stable and reliable in operation with the use of a controller 
ON EXACT FINITE DIFFERENCE SCHEME FOR THE COMPUTATION OF SECOND-ORDER FREDHOLM INTEGRO-DIFFERENTIAL EQUATIONS
Get PDFA special form of Non-Standard Finite Difference Method (NSFDM) called the Exact Finite Difference Scheme (EFDS) for the computation of second-order Fredholm Integro-differential equation shall be constructed in this research. In carrying out the construction of the method, it was assumed that at any point within the interval of integration, the approximate/numerical solution coincides with the exact/theoretical solution. The analysis of the method was also carried out to show that the second-order Fredholm integro-differential equation that possess solutions also have their corresponding EFDS. The method derived was then applied on some modeled second-order Fredholm integro-differential equations and from the results obtained, it is obvious that the EFDS derived did not exhibit any numerical instabilities. As a matter of fact, the computed solutions of the EFDS are exactly equal to the exact solutions 
ECONOMIC ASSESSMENT OF SOME SEED TREATMENT MATERIALS ON THE MANAGEMENT OF DOWNY MILDEW ON SELECTED PEARL MILLET CULTIVARS IN MAIDUGURI AND GOMBE, NIGERIA
Get PDFA field trial was conducted at Maiduguri and Gombe towns to assess the economic implications of All Star 40DS, Silicon dioxide (SiO2) and Diatomaceous Earth (DE) on the management of downy mildew (Sclerosporagraminicola(Sacc.) Schroet) in selected pearl millet cultivars. Split plot design was used where three cultivars (SOSAT-C88, Ex-Borno and LCIC-7902) were assigned to main plots while four seed treatment materials (SiO2, DE, SiO2 + DE, All Star 40DS) and control to sub plots and replicated four times.. The results obtained showed that in Maiduguri, all Star 40DS had the highest net benefit (₦ 114,617.86) and marginal rate of returns (1.20), followed by SiO2 + DE which gave the net benefit of (N 99, 663.57) and marginal rate of returns (1.00) while the control had the lowest net benefit (₦ 40, 617.86 ) and marginal rate of returns (0.40). The result of the combined analysis also showed that all the seed treatment applications translated into gain except with the control. There were also gains of ₦ 0.33, ₦ 0.21 and ₦ 0.15 from the application of All Star and SiO2 + DE respectively and loss of ₦ 0.19 from the control for every ₦ 1.00 naira that was spent. From the present results, SiO2 + DE treatment can therefore be used as an alternative to manage downy mildew of pearl millet as it is cost-effective, available and ecofriendly
Improved Security Techniques in Multi-Protocol Label Switching
Get PDFMulti-Protocol Label Switching has replaced Layer 2 ATM and Frame Relay technology for a while now, which provides high speed networking and traffic engineering. MPLS technology uses Label switching technique instead of IP routing when forwarding traffic to a destination, which makes it more scalable and flexible. However IP MPLS networks are not secure from outside threats and threats from within the network. In this paper, inherent security provided by a typical MPLS network is evalu-ated, and some combinations ofsecurity techniques are provided to improve upon it. To test some of the methods for enhancing the security of IP MPLS VPN network, two major attacks were carried out, i.e. Injection of IPv4 Routing Information, and Cracking of MD5 password with Authentication set to OFF and ON respectively. In order to protect the confidentiality, availability and integrity of data, in-herent security can be enhanced using step-by-step combination of the security techniques such as IP-Sec tunnels at the Customer Edge’s routers and a complexMD5 authentication between routing proto-cols. The MPLS network design was carried out to capture two locations in the UK, i.e. Newcastle and London. GNS3 Network emulator was used to achieve the desired results, with real Cisco IOS images, and finally, some thoughtful recommendations were provided, which are aimed at providing a better implementation of MPLS VPN on computer networks. 
ANALYSIS OF SOME ABUSED DRUGS AND PHARMACEUTICALS IN MUNICIPAL WASTE WATERS (EFFLUENTS)
Get PDFA study of myriads of chemical pollutants in aquatic environment was carried out from the effluent of Nottingham Sewage Treatment Works (STWs) in United Kingdom. Using a solid phase extraction - gas chromatography technique (SPE-GCMS), fifteen compounds detected in sampled STW effluents ranged between 1.1 - 33.5 ng L-1 with percentage recoveries of 78.6 – 97.8%. The most abundant compounds found in the final effluent were nicotine, ibuprofen, codeine, ephedrine, procaine, benzoylecgonine, lidocaine, andcaffeine, with mean concentrations of 21.4 ± 6.4, 16.7± 4.8, 15.1 ± 6.3, 10.1 ± 3.9, 9.1 ± 3.4, 5.6 ± 3.1, 5.3 ± 5.2 and 5.2 ± 1.9 ng L-1, respectively. The instrumental limits of detection (LODs) from 0.1 – 1.7 ng L-1, with standard deviations (STDs) of 1.1– 21.4% for all the compounds were also observed. The levels of illicit drugs and abused pharmaceuticals detected from the effluents showed the occurrence of these drugs and the Nottingham STW as one of the main transport routes to the receiving environment. These findings have further shown that chemicals in effluent get to the environment due to their incomplete removal from the STW. Persistence influx of these pollutants into the aquatic environment may have implication on ecosystems. 
KINETICS OF THE OXIDATION OF ORANGE II BY NITRITE ION IN AQUEOUS ACIDIC MEDIUM
Get PDFThe kinetics of the electron transfer reaction between Orange II(here and thereafter referred to as OII-) and nitrite ion in aqueous acidic solution has been studied spectrophotometrically (λ = 484 nm) at T = 27 ± 1oCin the acid range 1.0 × 10-2 ≤ [H+] ≤ 10.0 × 10-2 mol dm-3, ionic strength 0.1 ≤ [I] ≤ 0.7 mol dm-3 (NaCl). The reaction shows a first order dependence on [oxidant] and [reductant].The rate of the reaction increases with increase in [H+]. Plot of k2versus [H+] was linear with an intercept. The overall reaction conforms to the rate law: -d[OII-]/dt = (a + b[H+])[OII-][NO2-] The stoichiometry of the reaction is 1:2 (OII- : NO2-). Added cations and anions speed up the rate of the reaction. The results of spectroscopic investigation indicate that no intermediate complex is probably formedin the course of this reaction. The reaction is believed to proceed via the outersphere mechanistic pathway. 
FABRICATION, OPTICAL SYNTHESIZATION AND SYNTHESIZATION OF MANGANESE OXIDE (MnO) THIN FILMS DOPED WITH IRON (II) (Fe)
No full textThe fabrication, optical synthesization and synthesization of manganese oxide (MnO) thin films doped with iron (ii) (Fe) was studied using chemical bath deposition (CBD) technique. Manganese Oxide was doped with Fe (II) at different time and millage of 0.2M aqueous ammonia (NH4OH) solution. The effect of deposition time on complexed and non-complexed of iron doping on structure of the films were investigated. Optical analysis showed that MnO have high transparency at the near infra-red (NIR) region and could be possibly be used as material for poultry roofs and walls which is more advantageous than using the conventional methods of heating
A KNOWLEDGE MANAGEMENT-BASED DECISION-MAKING MODEL FOR PLANNING PATIENT DISCHARGE IN THE NIGERIAN HEALTH CARE SYSTEM
Get PDFThe Nigerian health care system (NHCS) is bedraggled with myriads of problems that had caused a major landslide of setback since independence. More pathetic is the fact that Nigeria health care has no concrete discharge planning (DP) and processes for patients admitted into her hospitals. The process of discharge is a critical phase in hospital management, and correction of it is a major strategy in NHCS. This is a major issue which nobody is looking into as it affects the convalescence of the patients. Effective Discharge Planning(DP) requires practitioners to have appropriate, patient personalized and updated knowledge in order to be able to make informed and holistic decisions about a patients’ discharge. This paper examines the role that Knowledge Management (KM) plays in planning an effective discharge plan. This paper also proposes KM models in healthcare and integrates KM with DP in the form of a KM based DP model for Nigeria health care system as the use of information and communications technology will increase productivity and efficiency in healthcare and large amounts of stored data will be of help to decision makers in practice.