A Framework for Evaluating Model-Driven Self-adaptive Software Systems

In the last few years, Model Driven Development (MDD), Component-based Software Development (CBSD), and context-oriented software have become interesting alternatives for the design and construction of self-adaptive software systems. In general, the ultimate goal of these technologies is to be able to reduce development costs and effort, while improving the modularity, flexibility, adaptability, and reliability of software systems. An analysis of these technologies shows them all to include the principle of the separation of concerns, and their further integration is a key factor to obtaining high-quality and self-adaptable software systems. Each technology identifies different concerns and deals with them separately in order to specify the design of the self-adaptive applications, and, at the same time, support software with adaptability and context-awareness. This research studies the development methodologies that employ the principles of model-driven development in building self-adaptive software systems. To this aim, this article proposes an evaluation framework for analysing and evaluating the features of model-driven approaches and their ability to support software with self-adaptability and dependability in highly dynamic contextual environment. Such evaluation framework can facilitate the software developers on selecting a development methodology that suits their software requirements and reduces the development effort of building self-adaptive software systems. This study highlights the major drawbacks of the propped model-driven approaches in the related works, and emphasise on considering the volatile aspects of self-adaptive software in the analysis, design and implementation phases of the development methodologies. In addition, we argue that the development methodologies should leave the selection of modelling languages and modelling tools to the software developers.Comment: model-driven architecture, COP, AOP, component composition, self-adaptive application, context oriented software developmen

Aerobrake assembly with minimum Space Station accommodation

The minimum Space Station Freedom accommodations required for initial assembly, repair, and refurbishment of the Lunar aerobrake were investigated. Baseline Space Station Freedom support services were assumed, as well as reasonable earth-to-orbit possibilities. A set of three aerobrake configurations representative of the major themes in aerobraking were developed. Structural assembly concepts, along with on-orbit assembly and refurbishment scenarios were created. The scenarios were exercised to identify required Space Station Freedom accommodations. Finally, important areas for follow-on study were also identified

The Extravagance of Imprisonment Revisited

This report analyzes prison and jail populations in the US as a whole and in four key states -- California, Florida, New York, and Texas -- to determine 1) how many prisoners are nonserious offenders and what it costs to lock them up, 2) what proven effective alternatives are in use and what they cost, and 3) what savings could be realized if a portion of the nonserious offenders were sentenced to alternatives instead of prison and jail

PROJECT OPTIMA: optimisation of policies for transport integration in metropolitan areas

The overall objectives of Project OPTIMA were: (i) to identify optimal urban transport and land use strategies for a range of urban areas within the EU; (ii) to compare the strategies which are specified as optimal in different cities, and to assess the reasons for these differences; (iii) to assess the acceptability and feasibility of implementation of these strategies both in nine case study cities (Edinburgh, Merseyside, Vienna, Eisenstadt, Tromsø, Oslo, Helsinki, Torino and Salerno) and more widely in the EU; and (iv) to use the results to provide more general guidance on urban transport policy within the EU

Measuring Aggregate Process Performance Using AHP

When one undertakes a benchmarking study, it is quite typical to collect performance data on a set of business processes from a variety of organizations. While one can compare efficiency on a process-by-process level, how can one compare the overall efficiency of one organization versus another using this process-level data? This note presents a methodology that combines tournament ranking and AHP approaches to create a ranking scheme that deals explicitly with missing data and ties in the tournament scheme.AHP, Benchmarking, Process Efficiency