Open Access Original Research Article

Optical Time Domain Reflectometer Assessment of Attenuation in Fiber Optics Communication System

J. Ilouno, I. J. Audu

Journal of Engineering Research and Reports, Page 1-6
DOI: 10.9734/jerr/2018/v1i49864

Attenuation is an undesirable factor that weakens the strength of signal as it travels down fiber optics. Attenuation level in every fiber communication link must be kept at its tolerable range in order to maintain good signal transmission. When the level of attenuation in a link is higher than the acceptable tolerance value, the transmission suffers some setbacks such as loss of signal, freezing of signal etc. An optoelectronic device, Optical Time Domain Reflectometer (OTDR) was used in the measurement of attenuations in the single-mode fiber using the uni-directional technique. It is a convenient and powerful tool for rapidly assessing attenuation behavior in optical fibers. It combines a detector and laser source to provide an inside view of the fiber link described by a trace. The injected light pulse from the laser source is received at the detector. OTDR traces were produced in accordance with the light pulses received. From these traces, the attenuation levels for the different fiber cores were obtained. An average attenuation limit of 0.188 dB/km and average section loss of 0.3dB for 1550 nm wavelength window over the span length of 1597.35 m were achieved which are within the acceptable standard range of 0.20 dB/km to 0.30 dB/km.

Open Access Original Research Article

Application of Electrical Resistivity Method in Site Characterization along Ado – Afao Road, Southwestern Nigeria

S. O. Ilugbo, A. D. Adebiyi, S. O. Olaogun, T. Egunjobi

Journal of Engineering Research and Reports, Page 1-16
DOI: 10.9734/jerr/2018/v1i49871

A geophysical study was carried out at a proposed location for the construction of a structure along Ado-Afao road, Southwestern Nigeria. The aim of the study is to evaluate the electrical properties of the soil for Founding of Engineering structures. The geophysical investigation involved the Vertical Electrical Sounding (VES) technique using the Schlumberger configuration with a total of twenty-one (21) VES within the investigated area. The electrode separation varies from 1 to 100 m. The geoelectric sections identified three to five geoelectric/geologic subsurface layers along the traverses. The topsoil comprising of clay, clayey sand and sandy clay with the resistivity values range from 28 to 800 Ω-m with its thickness varying from 0.4 to 1.9 m. The second layer was found to be lateritic with resistivity ranging between 200 to 800 Ω-m and thickness ranges from 1 to 7.5 m while the weathered layer comprising of clay, clayey sand and sandy clay with resistivity varies from 30 to 220 Ω-m and its thickness varies from 1.2 to 54 m. The fractured basement with resistivity value of 763 Ωm and thickness value of 8m while the fresh basement has a resistivity value ranging from 365 to 2964 Ωm with depth to basement ranging from 8 to 58 m. The resistivity values of the topsoil are indicative of clay, sandy clay and clayey sand. This layer may not be of any special interest since topsoil is normally excavated. Hence, foundation of the proposed structures cannot be found on this layer. Based on the investigation, the subsurface of the study area can be generally classified as incompetent. There is a presence of lateral inhomogeneity of the subsurface layers and geologic features such as fractures and faults. The construction in the area should be founded on the lateritic layer or fresh basement layer coupled with pile foundation to ensure the stability of the building. The choice of foundation material, clay content and topography elevation should be put into consideration.

Open Access Original Research Article

The Impact of Meteorological Conditions on the Value of Fresh and Hardened Concrete

Ezeliora, Chukwuemeka Daniel, B. O. Adinna, Ezenwa, V. Anayo

Journal of Engineering Research and Reports, Page 1-11
DOI: 10.9734/jerr/2018/v1i49874

The learning scrutinizes the influence of meteorological situations on fresh and case-hardened concrete formed in the South East, Nigeria. The variables considered in the research are temperature as well as relative humidity. The meteorological condition parameters were gained from Nigerian Metrological Agency in Lagos, Nigeria. The middling yearly temperature oscillated 26.39ºC to 32.49ºC was used as a control for the experiment. Slump and strength tests were conducted on concrete samples and results exposed that workability and compressive strength of the concrete was affected by temperature and relative humidity. It was discovered that concrete manufactured in the sunrise hours (9 am-12 noon) when the temperature and relative humidity were little have better quality than those manufactured in the late afternoon (2-4 pm) as portrayed by the results of the tests on the tables. However, the research acclaims that Professionals and other stakeholders in the construction practice should be aware that temperature and relative humidity partake to influence the quality of concrete during production on site. The research also inaugurates that the suitable time to produce high-quality concrete is between the hours of 9 am-2 pm and any other time will call for the use of admixture to produce concrete of similar quality although of a higher cost thus, affecting the budget of the project. In conclusion, professionals in practice are recommended to ensure effective supervision during concrete production.

Open Access Original Research Article

Regression Analysis Based Effective Manpower Planning Methodology: A Case Study

B. O. Akinnuli, R. K. Apalowo

Journal of Engineering Research and Reports, Page 1-12
DOI: 10.9734/jerr/2018/v1i49878

Adequate staff-students ratio (SSR) is one of the important National Universities Commission (NUC) prescribed criteria to be implemented in manpower planning by Universities in Nigeria. Forecasting manpower requirement has been used for economic planners and even the academic sector. In other to avoid imbalance, the manpower requirement is very vital in determining the desired output in a system. This study is aimed at predicting the adequate manpower required in a unit of an academic institution. Manpower related data of the Mechanical Engineering Department, Federal University of Technology, Akure Nigeria were collected. The data collected includes manpower capacity and students population over a period of thirteen consecutive years. The regression analysis based model was formulated and applied to analyze the collected data. Based on the analyzed data, trends of , , and  are obtained respectively for the student's population size, lecturers and technical staff requirements, where  and X are economic indicators. The obtained trends equations were then subsequently applied to compute SSRs and recommendations were made. The developed model was implemented in a computer software, using the Visual Basic programming language, in order to facilitate its solution procedure. The outcome of this study will aid the management of the institution in effective manpower determination and students number projection in future years. This will also assist the institution to plan for effective SSR based on the recommendation of NUC.

Open Access Original Research Article

Impact of Partially Treated Wastewater on Downstream Water Quality of Notwane River in Botswana

Gilbert K. Gaboutloeloe, Gugu Molokwe, Benedict Kayombo

Journal of Engineering Research and Reports, Page 1-9
DOI: 10.9734/jerr/2018/v1i49882

The impact of partially treated wastewater on the water quality of Notwane river stretch in the Gaborone region of Botswana was investigated. Water samples collected at effluent discharge point and three other sampling sites downstream were analyzed for pH, temperature, Biological Oxygen Demand (BOD5), Ammonia-nitrogen (Ammonia-N) and Nitrate-nitrogen (Nitrate-N). Sampling was conducted bi-weekly between February 2013 and April 2013. The ranges of measured parameters were:  pH (7.6-8.5), temperature (22-23ºC), BOD5 (11.2-27.0 mg/l), Ammonia-N (2.4-60.5 mg/l), Nitrate-N (20.6-28.6 mg/l). Analysis of variance, Games-Howel multiple comparisons and Pearson correlation were used to separate variable means. The results signal river non-point pollution due to runoff inflow of organics mainly from land use and domestic waste dumping by nearby dwellings. Temperature, BOD5, and pH range values were all within the Botswana Bureau of Standards (BOBS) limit while the maximum Ammonia-N and Nitrate-N were above BOBS limit by 50.5 mg/l and 6.6 mg/l, respectively. Regulations on indiscriminate waste dumping and discharge standards adherence should be enforced.