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This research paper examines the effectiveness of the yield spread in forecasting future economic activity and inflation in Nigeria. Quarterly data on GDP, Open Buy Back (OBB) Nigerian Treasury Bill (NTB), FGN Bond yields and inflation rates from 2010Q1 – 2020Q1 were employed in conducting this study. The Regression Model was used to establish the relationship among the variables of interest; the yield spread (10-year less 3-month bond) was used to predict output and inflation using the Dynamic and Static Forecasting Model. The projected variables, however, depicted co-movement between the actual and the forecasts in most of the periods. Nevertheless, the behavioral movement of the model was dissimilar at some points (2015-2017). Generally, the results indicated a significant predictive power of the yield spread in forecasting economic activities in the future as stipulated in the literature. The paper recommends the validity and use of the predictive information content embedded in the yield spread as a guide or signal for monetary policy actions and decisions.

In the past years, when wireless network improvement occurs from 1G/2G to third generation (3G), the rate in the use of real-time traffic oriented applications for voice, video and data increases. Consequently, the bandwidth to be backhauled from the cell site to the mobile switching center increases rapidly. 3G network is most prevalent in Nigeria with wide area of coverage. However, in recent times, poor subscribers’ mobile broadband experience is still the major challenge faced by many GSM operators. One of the major causes of this challenge is the use of wrong backhaul for radio access network (RAN). This lead to poor traffic throughput, high packet loss or frame loss at the cell edge. To overcome this challenge, the use of appropriate backhaul technology is crucial. Third Generation Partnership Program (3GPP) recommends the use of either asynchronous transfer mode (ATM) or internet protocol (IP) as the backhaul technologies for its RAN. This paper presents the performance analysis and the comparison of the ATM RAN and IP RAN backhaul technologies using six different 3G sites (with 3G base stations) located at Ado local government area of Ekiti State, Nigeria. The performance of each base station with different backhaul technology was evaluated in term of average maximum throughput per day. The effect of frame loss (for ATM RAN network) and packet loss (for IP RAN network) on traffic throughput were also analyzed. The comparison of the overall result analysis shows that the 3G base stations with IP-based RAN backhaul has better performance than the base station with ATM-based RAN backhaul.

The design of bevel gear for use in the development of revolving rostrum is presented. The pinion gear is designed to rotate at 1400 rpm for the output gear of 23 rpm. A suitable gearmotor was selected for the design based on the bevel gear design analysis. The motion is transmitted to the rostrum via a shaft keyed to it with a gib-head key and assembled on the rostrum with a spline connector. The analysis of the bevel mesh shows that maximum deformation of about 26.552 mm occurs in the pinion due to the loading the pinion tooth. The deformation of the tooth is observed to affect considerable the performance of the system. The transmission efficiency of the mechanism was obtained as 86% though effective for the operation of the system but could be improved by a more careful material selection for the bevel gear mesh.

Rice is one of the most important cereal crop in the world. This paper present the design and performance evaluation of a rice hulling machine fabricated for removing chaffs from paddy rice as the consumer’s demand for rice requires the most hygienic, easy and less time consuming process. The design was segmented into the hopper and housing (processing) unit, the frame support and the power transmission unit. The housing unit consists of the upper and lower body where the sieve, hulling blade and cylinder is enclosed. The machine is powered by a 3.0 H.P. 950 rpm electric motor via a V-belt mechanism which deliverers the power requirement to the shaft on which the hulling cylinder is mounted. The hulling cylinder presses the paddy rice against the hulling blade to remove the chaff. The paddy rice is fed into the housing unit for processing through the machine hopper. The probability failure of the machine during loading has been minimized by proper material selection and using a factor of safety of 4 in the design process. The machine was designed to process about 8 kg of rice for small scale production. Performance evaluation of the machine shows that its efficiency is within the range of 83 to 88%, the hulling capacity is within the range of 22 to 25 kg/h and the maximum efficiency is at 5 kg paddy rice hopper loading which is about 60% of the hoppers’ volume. Key words: Rice, hulling, dehusking machine, paddy, fabrication.

Design and Engineering Economic Analysis of two widely used Air-Conditioning (AC) systems, Mini-Split and Variable Refrigerant Flow (VRF), in the new Engineering Complex Building under the same indoor and outdoor conditions for an entire year is carried out by using Carrier Hourly Analysis Program software for cooling load estimation, and the Net Present Worth Analysis for Economic Analysis of both systems. Both systems are direct expansion air conditioning systems; hence the cooling load estimation was done using the ASHRAE transfer function method embedded within the Carrier software. Equipment to be used in analysis were selected from the Toshiba selection catalogues (Mini Split system), while that for the VRF system was selected using Toshiba simulation software. The annual energy analysis of both systems indicated that the VRF system will require more energy to run on an annual basis than the Mini Split system. However, the analysis was carried out without considering the part load potential energy savings of the VRF system. Net Present Worth Analysis carried out also favoured the Mini Split system in terms of Net Present Value of the systems. Based on the Engineering Economic Analysis carried out on the two systems, the overall Net Present Value for the VRF system is N77,891,808.66, while that of the Mini-Split system is N46,641,828.74. This result shows that the VRF system has a higher cost implication than the Mini-Split system. Hence, in terms of cost, the Mini-Split system is a more viable option.

Tiger nut tuber is rich in energy content, nutrients and minerals. The tuber which is usually stored dried could be processed by rehydration to improve the extraction of the milk content. The machine is developed to extract the milk contents of the crop for purpose of consumption and other usages. The design is made of the feeding segment, the extraction segment, power segment and the frame support which serves as the machine subassemblies. The design of the screw and drive mechanism is emphasize to ensure efficient performance of the machine. The machine is driven by a belt drive system powered by a 2 hp. electric motor operating at a speed of 1100 rpm. The efficiency of the machine is within the range of 53-55% for a power requirement of 1.514 kW. The machine is found suitable for small scale operation. Keywords: extractor, tiger nut, auger screw, hopper