MATHEMATICAL TIME-COST MODEL FOR INSTITUTIONAL BUILDING PROJECTS IN NIGERIA

Baba Shehu Waziri

Department of Civil and Water Resources Engineering

University of Maiduguri, Maiduguri, Nigeria

E-mail: shehuwaziri@yahoo.co.uk

ABSTRACT

The accurate prediction of construction time at the early project stage is essential to incorporate realistic project duration in the bid package. The study investigates the application of the Bromilow’s Time-Cost Model (BTC) to predict the construction duration of institutional building projects in Nigeria. Sixty (60) completed project data were used for the analysis. Linear regression was performed to explain the linear relationship between cost and time variables of the data. The result indicates a strong linear relationship between construction cost and construction duration with coefficients of correlation R= 0.808 and coefficient of determination R² = 0.670. Double log (log-log) regression was also employed in the form of the BTC model to determine the values of K and β which indicate general level of time performance and the sensitivity of the time performance affected by project size as measured by cost respectively. The low K value of 20.1 demonstrates that the time performance of the construction industry has improved compared to previous surveys while β value of 0.686 indicates a greater influence of project complexity on time prolongation. The model also showed a good fit to the data with R value of 0.845 and R² value of 0.716. The model showed a satisfactory prediction performance with MAPE of 13.6% over the test sample.

Keywords: Time-Cost, Cost, duration, Bromilow model, regression.

CHARACTERIZATION OF BREWERY EFFLUENT FLUID

¹U. E. Inyang, E. N. Bassey and J. D. Inyang

¹Department of Chemical and Petroleum Engineering

University of Uyo, Uyo, Akwa Ibom State

Email: uweminyang7@yahoo.com

ABSTRACT

This paper reports on the characterization of effluent fluid from different sections of a brewing plant with respect to the constituents and their toxicity level for possible classification and reuse within the system. The results showed the effluent fluids had moderate Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) of 40.30 mg/l and 471mg/l respectively. The suspended solids were also found as 81mg/l. From the study, it was found that there was the possibility of re-use of the effluent from bottle washing section before discharging to the environment.

Key Words: Effluent Fluid, Biochemical Oxygen Demand, Chemical Oxygen Demand, Total Organic Carbon.      

THE APPLICATION OF NOMINAL GROUP TECHNIQUE AS A DECISION MAKING TOOL

¹Odu O. Godwin, and ²Okereke N.

¹Department of Mechanical & Production Engineering, Delta State University, Abraka, Oleh   

 ²Department of Mechanical & Production Engineering, Delta State University, Abraka, Oleh   

E-mail:odugodwin@gmail.com, ndububa.okereke@yahoo.co.uk

ABSTRACT

Decision-making has always been a problem to decision makers. Though the problem of relative importance of issues or criteria has been a major concern. In practice, it is difficult even for an individual as a decision maker to arrive at a consensus. Similar in format to a focus group, the nominal group technique is essentially an organized discussion with a small group of participants. This paper describes and demonstrates how nominal group technique can be adopted as a decision tool in solving problems relating to relative importance of issues. The benefits associated with it were equally discussed.

Keywords: Nominal group technique, Team, Decision-making, Group discussion, Ideas

        Ranking, prioritized.

LOW COST SOLAR POWERED ULTRA VIOLET PURIFICATION SYSTEM FOR RURAL COMMUNITIES

¹Omitade, O, ²Ajani, O.O, and ³Akanbi, R.A Ogedengbe S.

¹School of Engineering, Durham University, Durham, England

²Department of Physics and Solar Energy, Bowen University, Iwo, Nigeria

³Department of Physics, The polytechnic, Ibadan, Nigeria

E-mail: aj_ani2000@yahoo.com

ABSTRACT

Identification of the need to solve the acute problem of affordable and efficient water purification system in most rural communities in developing countries prompted the research into the use of solar powered ultra violet purification system. Nigeria, a country in west Africa is used as a case study with an abundant solar radiation estimated to be an average of about 3.5Kwh/m²  daily. Nigeria is faced with a lot of environmental issues with majority occurring in the Niger delta area as a result of oil spillage and other contaminations. Review of existing water purification systems was carried out and its various limitations identified. The advantages and possibilities of providing safe and potable water through the use of a locally designed model of a solar powered ultra violet water purification system was carried out.Results from the model shows in addition to its efficiency, a highly reduced and affordable cost, thereby making its adoption cost effective.

Keywords: Water purification, Ultra violet, Oil spillage, rural communities, Niger                     Delta. Potable water and Solar radiation

THE STUDY OF A CHARCOAL STOVE

 ¹F.E. Ukrakpor  ²P.A Kuale

¹ Department of Mechanical Engineering Delta State University, Oleh Campus

² Department of Electrical Engineering Delta state University, Oleh Campus

ABSTRACT

This paper investigates Charcoal stoves. Many types are looked at and examined in search for systematic design method leading to a more accurate method for producing and forming the templates. It is predicted that, with growing charcoal production and use, the use of charcoal stove in the average low income home may grow. Besides as long as trees’ planting is made law and obeyed, charcoal as a source of energy will perhaps be one of the most reliable and renewable energy source (other than solar energy) in Nature, on which a nation can rely for part of energy requirements if necessary balance of reforestation and deforestation is maintained.

DETERMINATION OF ENERGY PRODUCTION POTENTIAL OF WIND RESOURCES IN LAUTECH OGBOMOSO, NIGERIA

Sanusi Y.K. and Adedokun O.

Department of Pure and Applied Physics

 Ladoke Akintola University of Technology Ogbomoso. Oyo State. Nigeria.

E-mail adedokunoluwaseun@yahoo.com

ABSTRACT

This work presents a study of wind resources in Ladoke Akintola University of Technology, Ogbomoso Area. The experimental measurement of wind speed and wind direction data were collected from Nigeria Meteorological Agency (NIMET) Oshodi, Lagos for a period of four years, 2006, 2007, 2008 and 2009. The annual mean wind speed of LAUTECH, Ogbomoso located on (Latitude 8^o 5′ S and Longitude 4^o 12′ W), was estimated to be 37.99m/s through the monthly wind speed and wind direction data collected. The annual energy capture potential of 1081.79MJ is obtained for a single wind power system applying the power law equation with MS visual basic programming Language. The obtained equivalent power potential of 123.99kW is a considerable amount when compared with power consumption of 1200kW utilized in Lautech Ogbomoso. It is then realized that the energy capture potential for a single wind turbine is 10.33% of the power consumption in Lautech through conventional energy source. Thus, we suggest that power potential from wind resources can be used to supplement the power potential of conventional energy in Lautech.

Keywords: Energy potential, power potential, Wind speed, Power law equation, wind turbine                         

MODELLING, SIMULATION AND CONTROL OF ETHYL ACETATE REACTIVE DISTILLATION COLUMN USING CHEMCAD

Amenaghawon, Nosakhare Andrew ¹ and Ogbeide, Samuel. E ²

 Department of Chemical Engineering,

University of Benin, Benin City, Nigeria

E-mail: andrew.amenaghawon@uniben.edu /samuelogbeide@gmail.com

ABSTRACT

The modelling, simulation and control of a reactive distillation column for the production of ethyl acetate from acetic acid and ethanol has been studied using commercially available process simulation software, CHEMCAD^®. The effects of key operating variables such as reflux ratio, distillate rate, feed tray location and activity model on the composition of ethyl acetate in the distillate at steady state were studied. Steady state simulation results show that if a double feeding strategy is adopted, acetic acid must be fed to the tray 2 while ethanol must be fed to tray 12 in order to obtain optimum composition of ethyl acetate in the liquid phase. Also, a reflux ratio of 12 resulted in optimum composition of ethyl acetate in the liquid phase. Increasing the distillate rate resulted in an increase in the composition of ethyl acetate in the liquid phase. Using the steady state results as an initial state, dynamic simulations were run for the purpose controlling the reboiler pressure and ethyl acetate purity. For pressure control, the Ziegler-Nichols (ZN) tuning method was used to tune the controller parameters resulting in an optimal value of integral square error (ISE)of 587.85 and corresponding values of 0.13 and 7.05 for proportional gain and integral time constant (and ) respectively. A simulation exercise such as presented in this work is very important and is increasingly becoming popular. This is because simulation of mathematical models of chemical processes is safe, cheap and less time demanding. This has also been helped by the development of computers with high computational capabilities.

Keywords; Steady-state, Dynamics, Control, Reactive distillation, Ethyl acetate

INVESTIGATING THE STRENGTH AND POROSITY CHARACTERISTICS OF SOME FIRED CLAYS IN EDO AND DELTA STATES

*S.A. Agbalajobi¹ and I.S. Omoijuanfo²

²Department of Mines, Federal Ministry of Power and Steel, Abuja, Nigeria

Email: wisdammy@yahoo.com

ABSTRACT

Investigation aimed at determining the strength and porosity characteristics of some fired clays in Edo and Delta States was carried out. Eighteen different clay samples were taken from six locations in both states. Three samples were taken from each location, analyzed and the result averaged. The six locations were Afuge/Ojavu, Usen/Arhenwen, Uguoriahi/Ovbere in Edo State and Ozarra/Ewebi, Ozalla/Ezeko and Iguoriakhi/Ogbomoba in Delta and Edo State. The clay samples were mixed repeatedly, quartered and analyzed to test their porosities and fired strength characteristics, using American Standard Thermal Analysis Method at the Soil Science Test Laboratory of the Ahmadu Bello University, Zaria. The results of the analysis showed that clay deposits in Afuze/Ojavu, Usen/Arhenwen, and Uguoriakhi/Ovbere in Edo State are good for brick works. They have low porosities ranging from 0.95% to 24.31% and high fired strength. On the other hand, clay deposit from Ozarra/Ewebi, Ozalla/Ezeko and Iguroriakhi/Ogbomoba in both Edo and Delta State are good for pottery. They have high porosities ranging from 13.0% to 38.74% and low fired strength.

Key Word: Clay, refractory, porosity, pottery, fired strength, temperature    

INVESTIGATION INTO THE USE OF LOCAL CLAYS IN DRILLING OPERATIONS

P.N. Onwuachi-Iheagwara

Department of Petroleum and Gas Engineering

Delta State University, Abraka, Oleh Campus, Nigeria

pniheagwara@gmail.com

ABSTRACT

Local clays were treated with chemical additives. Their rheological and thixotropic properties evaluated to determine their suitability for drilling operations. Properties examined included the Swelling Index, Apparent Viscosity, Plastic Viscosity and the Yield point.  Result shows that that the Nigerian indigenous clays are suitable. More research is recommended.

Keyword:  rheological properties, Nigerian clay, drilling clays