These practice materials are intended to give IELTS candidates an idea of what the test is like and to test themselves to see whether their English is at the level required to take the IELTS.

A brand new title in this popular series of Tests that teach, designed to help improve student's exam performance and increase language competence. The PTE Academic Testbuilder supplies four complete practice tests for the entirely computer-based Pearson Test of English Academic exam.

Throughout most of the twentieth century, electric propulsion was considered the technology of the future. Now, the future has arrived. This important new book explains the fundamentals of electric propulsion for spacecraft and describes in detail the physics and characteristics of the two major electric thrusters in use today, ion and Hall thrusters. The authors provide an introduction to plasma physics in order to allow readers to understand the models and derivations used in determining electric thruster performance. They then go on to present detailed explanations of: Thruster principles Ion thruster plasma generators and accelerator grids Hollow cathodes Hall thrusters Ion and Hall thruster plumes Flight ion and Hall thrusters Based largely on research and development performed at the Jet Propulsion Laboratory (JPL) and complemented with scores of tables, figures, homework problems, and references, Fundamentals of Electric Propulsion: Ion and Hall Thrusters is an indispensable textbook for advanced undergraduate and graduate students who are preparing to enter the aerospace industry. It also serves as an equally valuable resource for professional engineers already at work in the field.

An integrated package of powerful probabilistic tools and key applications in modern mathematical data science.

This short course includes 40-50 hours of essential exam practice, tips and strategies to prepare students for the Cambridge ESOL PET examination. PET Direct prepares students for the Cambridge ESOL PET examination. The Workbook with answers provides twelve units of additional language practice and includes a complete practice test.

"This book is about the use of modern statistical methods for quality control and improvement. It provides comprehensive coverage of the subject from basic principles to state-of-the-art concepts. and applications. The objective is to give the reader a sound understanding of the principles and the basis for applying them in a variety of situations. Although statistical techniques are emphasized. throughout, the book has a strong engineering and management orientation. Extensive knowledge. of statistics is not a prerequisite for using this book. Readers whose background includes a basic course in statistical methods will find much of the material in this book easily accessible"--