ABSTRACT BIOLOGICAL SULPHATE REDUCTION USING PRIMARY SEWAGE SLUDGE AS ENERGY SOURCE IN AN UPFLOW ANAEROBIC SLUDGE BED REACTOR Since the economics of biological sulphate reduction (BSR) are driven by the economics of the organic carbon source, the BioSURE® process has been developed as a low-cost effective system where primary sewage sludge (PSS) is used as the energy source. This research investigates the use of PSS for BSR in an upflow anaerobic sludge bed (UASB) reactor in detail in ord...
ABSTRACT South Africa is possibly facing the biggest housing backlog in its history, and the backlog is growing annually. The ability and means to deliver must be improved, together with a compromise between the construction materials used and the occupants' preferences. This study seeks to examine the use of concrete block construction for the wall superstructure of low cost housing in terms of affordability and acceptability by the end-users. Three objectives of this research study, which ...
Abstract An anisotropic damage model is proposed for the constitutive description of microcracking processes in brittle rock under a general loading path. Experimental data and micromechanical models are reviewed to quantify the effect of microcracking on the material stiffness and the mechanisms of microcrack formation in brittle rocks under compression are discussed. The sliding crack concept is adopted as the micromechanical basis of the anisotropic damage model. Undamaged material is rep...
ABSTRACT MATHEMATICAL SIMULATION OF DYNAMIC BEHAVIOUR OF SECONDARY SETTLING TANKS The main objective of this thesis was to briiig the theoretical and practical aspects of secondary settling tank developments closer together. This was achieved firstly, by evaluating and developing empirical relationships from which the flux theory constants may be derived from simpler sludge settleability measures; and secondly, by developing a computer model for the simulation of dynamic behaviour of full sca...
In this research was to highlight the most important sources possessed by any organization to achieve its desired image and increase their rate of production and increase their profits and expand their activities, making the construction industry in Sudan industry with many benefits such as opening business opportunities for human cadres in various specializations and take advantage of them and their energy and experience to the labor market in Sudan and work the establishment of proj...
ABSTRACT Thousands of Base Station Antennas (BSA) have been installed in Nigeria to support the development of mobile telephony. At the same time there is a public concern about the electromagnetic fields radiated by these antennas, particularly there is a great fear by those living in the vicinity of these antennas, of being exposed to the harmful effects of this radiation. This fear has created the need to investigate and establish the level of radiation and also determine whether this lev...
ABSTRACT The study examined the state of health and safety risk management practices in the building sector of the construction industry and has the objectives to: evaluate the construction risks inherent in the building sector of the construction industry; examine the health and safety risk management processes adopted by the construction industry in Nigeria; validate the existence of identified factor(s) militating against the implementation of health and safety practices in the constructi...
ABSTRACT Pavement markings are lines drawn on a pavement surface to provide vital information to road users pertaining to lane restrictions and vehicle movements, which if adhered to, results in improved safety and smooth travelling to road users. Pavement markings’ visibility is quantified into a parameter called retroreflectivity, which is a measure of how well the markings can be seen by road users. The importance of the factors affecting pavement markings differs from one publication t...
Compliant mechanisms (CMs) above the traditional rigid-body mechanisms have the sole merit of no relative moving parts hence preventing any form of wear, backlash, noise and need for lubrication. Its applications are versatile and fully domicile in such sectors as medicine, robotics, aerospace, biomechanics, food processing and automotive industries to mention a few. The Pseudo Rigid Body (PRB) equivalence of compliant mechanisms have been the conventional approach used by earlier researchers...
ABSTRACT The march of globalization and international trade has brought into focus the need for the measurement of quality as an essential element for customer satisfaction. Earlier approaches to quality control based mainly on end product testing are no longer considered adequate enough as quality must now be assured at every developmental or production stage to guarantee quality product at the end. Thus, non-subjective and non-destructive methods are receiving attention especially where the...
ABSTRACT The steady-state two-dimensional problem of combined free and forced laminar convection with upward flow in inclined rectangular channels heated from below and cooled from above, has been investigated by numerical, parameter perturbation and experimental methods. The results indicate that for air (Pr = 0.73), maximum heat transfer rates occur at the hotwall for inclinations between 30° and 60° to the horizontal. In addition, the perturbation analysis predicts the occurence of maxim...
ABSTRACT This work improves upon the Potential Field Method (PFM) for the navigation of autonomous mobile robots, through the introduction of a new Hybrid Virtual Force Field (HVFF) concept. The HVFF concept integrates the virtual force field (VFF), which is based on the principles of artificial attractive and repulsive potentials, with the virtual obstacle concept (VOC) and the virtual goal concept (VGC). In particular, the specific challenges resolved by the HVFF include the local minimal p...
ABSTRACT Two Dimensional Laminar Free Convection in a fluid contained in a long horizontal right triangular enclosure has been investigated using numerical techniques and an experimental study. The geometry of the enclosure is such that the base is assumed horizontal while the vertical height is adiabatic. Motion in the region is set up by heating the hypotenuse while cooling the horizontal wall. This model simulates heat transfer problems associated with pitched-roofs with suspended ceilings...
STRACT Global warming is a serious problem facing the world today as well as the world in the future if left unchecked. In order to stop or avert this problem, our today’s society must change her ways, by learning how to alter what they do or use in order to be less harmful to the environment. Making our buildings and general structural facilities “green” would greatly impact this problem. There are many ways for this to be done and more ways are being developed rapidly. As these new de...
ABSTRACT The study was aimed at developing mathematical models on the hydraulic performance of Sandbags as Checkdam for erosion control. Pilot studies were carried out at two sites. Site ‘A’ was a natural gully at a location in Ezinihitte-Mbaise, Imo State while site ‘B’ was an artificial channel excavated on the slope of Otamiri River at Federal University of Technology, Owerri. Artificial runoff was simulated into site ‘B’ by pumping water from Otamiri River. Sandbags of ...