Constitutive Modeling of Wind Energy Potential of Selected Sites in Nigeria: A Pre-Assessment Model

In this chapter, the authors present the result of a study carried out to develop a pre-assessment model that can be used to carry out a preliminary study on the availability of wind energy resources of a site. 21 years’ (1987 – 2007) monthly average wind speeds for 18 locations in Nigeria were used to create the simple constitutive model. The locations span across the six geopolitical zones of the nation with three stations from each zone. Various statistical procedures were employed in the development of the model. The outcome gave an empirical model, which if employed, will lead to determining the mod- est range of wind energy potential of a site. Further, the results from this model were compared with those from the well-established two-parameter Weibull statistical distribution function and found to be reasonably adequate. Thus with this model, decision on site selection for complete assessment can be made without much rigour

Assessment of Wind Power Potential and Wind Electricity Generation Using WECS of Two Sites in South West, Nigeria

The study was used to analyze the wind characteristics of Shaki (08.40’ N; 03.23’ E; Altitude 457.0 m; Air density 1.1723 kg/m3) and Iseyin (07.58’ N; 03.36’ E; Altitude 330.0 m; Air density 1.1869 kg/m3), two local sites in Oyo State, Nigeria. 21 years monthly mean wind speeds at 10 m height obtained from the Nigeria meteorological department were employed together with the Weibull 2-parameter distribution and other statistics to carry out monthly, seasonal and whole years’ analyses of the sites’ wind profiles for electricity generation. It was found that the whole data spread ranged between 0.9 and 9.1 m/s for the two sites while the 21 years’ average ranged between 3.2 and 5.1 m/s and 2.9 and 4.7 m/s for Shaki and Iseyin sites respectively. Three wind energy conversion systems were employed with the results and it was discovered that, the sites have capacity to generate MWh to GWh of electricity at an average cost/kWh of between € (0.025 and 0.049) and that a turbine with technical parameters of cut-in, cut-out and rated wind speeds of 3.0, 25 and 11.6 m/s is appropriate for the sites

Electrohydrodynamic control valve Patent

Control valve for switching main stream of fluid from one stable position to another by means of electrohydrodynamic force

Spherical pipe joint delivers loads equally to mating flange

Oxidizer inlet duct with a ball joint pipe fitting incorporating two spherical bearing races and balls in contact with centering cage springs transmits an evenly distributed load to the mating flange. This design should find application in piping systems where unequal load distributions exist

Soft frame adjustable eyeglasses Patent

Pliable frame for sunglasses in emergency survival kit

Assessment of wind energy potential of two sites in North-East, Nigeria

The study is used to assess the wind energy potential of Maiduguri and Potiskum, two sites in North-East, Nigeria. 21 years (1987e2007) monthly mean wind data at 10 m height were assessed from the Nigeria Meteorological department and subjected to 2-parameter Weibull and other statistical analyzes. The result showed that average monthly mean wind speed variation for Potiskum ranged from 3.90 to 5.85 m/s, while for Maiduguri, it ranged from 4.35 to 6.33 m/s. Seasonally, data variation between the dry and wet seasons revealed that, the mean wind speed variation for Potiskum ranged from 4.46 (for dry) to 5.16 m/s (for wet), while for Maiduguri it ranged from 5.10 (dry) to 5.59 m/s (wet). The wind power density variation based on the Weibull analysis ranged from 102.54 to 300.15 W/m2 for Potiskum and it ranged from 114.77 to 360.04 W/m2 for Maiduguri respectively. Moreover, Maiduguri was found to be the better of the sites in terms of monthly and seasonal variation of mean wind speed, but they both can be suitable for stand alone and medium scale wind power generation

Developing Mathematical Learning Device Using Ttw (Think- Talk-Write) Strategy Assisted By Learning Cd To Foster Mathematical Communication

This research aims to produce mathematical learning device or tool using TTW strategy that is valid, practical, and effective. The developed device consists of syllabi, Learning Implementation Plan (RPP), Student Reading which is packaged in CD (BBS), and an evaluation tool. Receiver of treatment or Subjects are the eighth grade students of Muhammadiyah Junior High School in Purworejo. First experiment held in the class A of eighth grade students aimed to determine the legibility of device and the level of difficulty, distinguishing features, and reliability test learning outcomes. Second experiment conducted in class C of eighth grade students aimed to verify the practicality of the device and the effectiveness of learning using developed devices, whereas the class G is as control class. Results from 5 validations of the device are: the mean score of syllabi is 3.48; RPP is 3.79; BBS is 3.73; LKS is 3.73; assessment tool is 3.71 (on scale 1-4). Such results mean that validation criteria of the device is valid. The score of experiment results showed that the criteria of learning process is 3.80; the students’ response is 93.85%; the teacher’s score is 3.91, that means it’s a practical device. Learning using the devices results a classical learning mastery, and achievement test of an experimental class is better than the control class. Furthermore, student’s activity has a positive influence for achievement, so it’s the effective device. Key words: developed device, Think-Talk-Write (TTW), the mathematical learnin