Oscillations

Understanding nanotechnology using analogies: macroscale physics simulator and nanoscale back-of-envelope calculationss

For many years neutrino was considered a massless particle. The theory of a two-componentneutrino,whichplayedacrucialroleinthecreationofthetheoryof theweakinteraction,isbasedontheassumptionthattheneutrinomassisequalto zero. We now know that neutrinos have nonzero, small masses. In numerous exp- iments with solar, atmospheric, reactor and accelerator neutrinos a new p- nomenon, neutrino oscillations, was observed. Neutrino oscillations (periodic transitionsbetweendifferent?avorneutrinos? ,? ,? )arepossibleonlyifneutrino e ? ? mass-squareddifferencesaredifferentfromzeroandsmalland?avorneutrinosare “mixed”. The discovery of neutrino oscillations opened a new era in neutrino physics: an era of investigation of neutrino masses, mixing, magnetic moments and other neutrino properties. After the establishment of the Standard Model of the el- troweak interaction at the end of the seventies, the discovery of neutrino masses was the most important discovery in particle physics. Small neutrino masses cannot be explained by the standard Higgs mechanism of mass generation. For their explanation a new mechanism is needed. Thus, small neutrino masses is the ?rst signature in particle physics of a new beyond the Standard Model physics. It took many years of heroic efforts by many physicists to discover n- trino oscillations. After the ?rst period of investigation of neutrino oscillations, manychallengingproblemsremainedunsolved.Oneofthemostimportantisthe problem of the nature of neutrinos with de?nite masses. Are they Dirac n- trinos possessing a conserved lepton number which distinguish neutrinos and antineutrinos or Majorana neutrinos with identical neutrinos and antineutrinos? Many experiments of the next generation and new neutrino facilities are now underpreparation and investigation. There is no doubt that exciting results are ahead.

This is a picture of Prof. Lewin, taken by Prof. Lewin. It was the "Astronomy Picture of the Day" (APOD) on September 13, 2004. It was also presented to his 8.03 students as a challenge to obtain extra course credit if they were able to explain this phenomenon. On December 7, Prof. Lewin revealed the physics (and demonstrated it) in lecture 22. The solution was also revealed by APOD to the many thousands of people who were puzzled by it and who tried to explain it.

This book reviews and examines how power system low-frequency power oscillations and sub-synchronous oscillations may be affected by grid connection of wind power generation. Grid connection of wind power generation affects the power system small-signal stability and has been one of the most actively pursued research subjects in power systems and power electronics engineering in the last ten years. This book is the first of its kind to cover the impact of wind power generation on power system low-frequency oscillations and sub-synchronous oscillations. It begins with a comprehensive overview of the subject and progresses to modeling of power systems and introduces the application of conventional methods, including damping torque analysis, modal analysis and frequency-domain analysis, presented with detailed examples, making it useful for researchers and engineers worldwide.

This book reviews and examines how power system low-frequency power oscillations and sub-synchronous oscillations may be affected by grid connection of wind power generation. Grid connection of wind power generation affects the power system small-signal stability and has been one of the most actively pursued research subjects in power systems and power electronics engineering in the last ten years. This book is the first of its kind to cover the impact of wind power generation on power system low-frequency oscillations and sub-synchronous oscillations. It begins with a comprehensive overview of the subject and progresses to modeling of power systems and introduces the application of conventional methods, including damping torque analysis, modal analysis and frequency-domain analysis, presented with detailed examples, making it useful for researchers and engineers worldwide.

by Toru Ohira (Editor), Tohru Uzawa (Editor)

Hydrodynamic equations well describe averaged parameters of turbulent steady flows, at least in pipes where boundary conditions can be estimated. The equations might outline the parameters fluctuations as well, if entry conditions at current boundaries were known. This raises, in addition, the more comprehensive problem of the primary perturbation nature, noted by H.A. Lorentz, which still remains unsolved.