Imre Pázsit is a professor at the Division of Subatomic, High Energy and Plasma Physics, Department of Physics at Chalmers University of Technology, Sweden, and an adjunct professor at the Department of Nuclear Engineering & Radiological Sciences of the University of Michigan, Ann Arbor, USA. His research interests include fluctuations in neutron transport, reactor diagnostics and the theory of multiplicity in nuclear safeguards. He has published over 200 articles in international journals and, together with L. Pál, is the author of the book Neutron Fluctuations - A Treatise on the Physics of Branching Processes. He is a fellow of the American Nuclear Society, a member of the Royal Swedish Academy of Engineering Sciences and the Royal Society of the Arts and Sciences in Gothenburg, and an Honorary Doctor at the Budapest University of Technology and Economics. He is also the holder of the Leo Szilárd Medal of the Hungarian Nuclear Society, the Order of the Rising Sun from the Japanese government, and the E.P. Wigner Reactor Physicist Award and the Don Miller Award from the American Nuclear Society.Hoai-Nam Tran is a professor at the Institute for Advanced Study, Phenikaa University, Vietnam. Professor Tran's research focuses on burning strategies and fuelling schemes for various reactor types, including high-temperature gas reactors and pebble bed modular reactors, their neutron characteristics and calibration, and diagnostics. Past positions include Chalmers University of Technology, Nagoya University and Tokyo Institute of Technology, Japan.Zsolt Elter works as a reactor physicist in the Swedish nuclear industry and is part-time employed as a researcher at the Division of Applied Nuclear Physics at Uppsala University, Sweden, where he teaches reactor physics. He earned his PhD in nuclear engineering under the supervision of Prof. Imre Pázsit from Chalmers University of Technology. His professional interests include Monte Carlo-based neutronics and radiation shielding simulations, as well as deterministic lattice physics methods.

• Chapter 1: IntroductionChapter 2: Principles of traditional reactor diagnostics and noise analysisChapter 3: A basic study of the structure of the core response in the basic planned Gen-IV types (metal-cooled, gas-cooled and molten salt reactors)Chapter 4: A basic study of the structure of the core response in the basic planned SMRsChapter 5: A survey of the dynamic core transfer calculational codes by the various groups worldwide, their principles, potentials for applications in Gen-IV systems and SMRsChapter 6: Developments of zero-power noise methods for fast reactor systemsChapter 7: Instrumentation and control systems diagnostics for next generation of nuclear reactorsChapter 8: Worldwide activities in design and planned diagnostics of SMRsChapter 9: Conclusions and future directionsAppendix A