Analytical solutions to the orbital motion of celestial objects have been nowadays mostly replaced by numerical solutions, but they are still irreplaceable whenever speed is to be preferred to accuracy, or to simplify a dynamical model. In this book, the most common orbital perturbations problems are discussed according to the Lie transforms method, which is the de facto standard in analytical orbital motion calculations.

Participatory Modelling for Resilient Futures: Action for Managing Our Environment from the Bottom-Up, Volume One provides an important contribution to environmental management by introducing an integrative framework for participatory research for better land use and natural resource planning, organized around compelling recent case studies. It is a valuable guide for the increasing number of students looking for solutions in sustainability science and also practitioners who are on the ground working with local communities to improve specific places. The book was developed in response to the need to provide a clear and synthetic account, in accessible and non-technical language, of the way in which innovative integrative research can help solve real world human-environment interaction problems at a range of levels and scales, e.g., participatory modelling to secure a sustainable future for a natural protected area, working with stakeholders to break the deadlock on renewable energy implementation in Europe or tackling social exclusion and reducing food carbon footprint through local agroecology schemes.