This study analyzed the spatiotemporal pattern of settlement expansion in Abuja, Nigeria, one of West Africa's fastest developing cities, using geoinformation and ancillary datasets. Three epochs of Land-use Land-cover (LULC) maps for 1986, 2001 and 2014 were derived from Landsat images using support vector machines (SVM). Accuracy assessment (AA) of the LULC maps based on the pixel count resulted in overall accuracy of 82%, 92% and 92%, while the AA derived from the error adjusted area (EAA) method stood at 69%, 91% and 91% for 1986, 2001 and 2014, respectively. Two major techniques for detecting changes in the LULC epochs involved the use of binary maps as well as a post-classification comparison approach. Quantitative spatiotemporal analysis was conducted to detect LULC changes with specific focus on the settlement development pattern of Abuja, the federal capital city (FCC) of Nigeria. Logical transitions to the urban category were modelled for predicting future scenarios for the year 2050 using the embedded land change modeler (LCM) in the IDRISI package. Based on the EAA, the result showed that urban areas increased by more than 11% between 1986 and 2001. In contrast, this value rose to 17% between 2001 and 2014. The LCM model projected LULC changes that showed a growing trend in settlement expansion, which might take over allotted spaces for green areas and agricultural land if stringent development policies and enforcement measures are not implemented. In conclusion, integrating geospatial technologies with ancillary datasets offered improved understanding of how urbanization processes such as increased imperviousness of such a magnitude could influence the urban microclimate through the alteration of natural land surface temperature. Urban expansion could also lead to increased surface runoff as well as changes in drainage geography leading to urban floods.

The power subsystem could possibly be the most underappreciated and forgotten of all of the on-board electrical subsystems. There may be several reasons for this, but the most likely is that most people just don't find the subject interesting enough. There are, of course, exceptions to this generalization, but it is safe to say that no one is currently planning a mission to demonstrate optimization of power system network. Grabbing the attention of spacecraft engineers are subjects like; more advanced communications systems, on-board data handling, and high speed data links, imaging systems, micro-propulsion, attitude control algorithms, sensors and actuators. It is natural that the best people in a small organization focus on the more exciting aspects of a mission; these subjects will typically be the differentiator of an organization's space mission from that of the rest of the world. However, it is also clear that these systems need power, and power that is delivered reliably and efficiently. For most companies and organizations planning their own microsatellite mission, the prospect of producing a reliable, yet affordable power system for their mission is not a trivial problem. Some non-traditional spacecraft manufacturers, such as Universities, are finding out the importance of a well-designed power system the hard way. The most common cause of failure on microsatellite mission to date has been the power system. As all microsatellite missions require some sort of optimization of power system network, and since this system will differ little from mission to mission, it makes sense to provide an off-the-shelf solution for common buses. By providing such a system, the responsibility of design of the power system within smaller organizations can be removed, allowing the mission design team to focus on the design of the rest of the spacecraft.

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