The book consists of 28 papers, presented at the NATO Advanced Study Institute on the Fundamentals of Friction, held in July 1991 in the German Harz mountains. The objective of the Institute was to bring together experts from the two fields of "classical" macroscopic surface mechanics, and "modern" surface science, including molecular dynamics and point contact microscopy of atomic resolution. Thus, friction phenomena are approached by macroscopic models and experiments, as well as by what is being learned at the microscopic level (in current jargon referred to as nano tribology). The papers are divided into seven chapters. Five deal with the classical macro aspects, while, not unexpectedly, only one is devoted to the atomic scale approach. One final chapter brings together three papers on self-induced stick-slip vibrations and instabilities in friction systems. The five macromechanical papers are mainly based on K. L. Johnson's continuum mechanical formulation of surface mechanics. (Johnson contributes an Appendix, summarizing the concepts of his well-known book "Contact Mechanics.") After an initial chapter with broader perspectives on energy dissipation (by D. Tabor) and fluctuations in friction (by E. Rabinowicz), a second chapter is focused on adhesion contributions to frictional forces, both between smooth and rough surfaces and between particles in granular materials. Chapter 3 deals with fracture, deformation, and shear of the sliding interfaces, while Chapters 4 and 5 treat lubricated contacts from the tribochemical point of view and with respect to molecularly thin surface films. The sixth chapter represents the atomic scale approach to friction. An introductory paper by McClelland and Glosli presents two atomistic models for friction as well as frictionless and wearless sliding contacts. The models are applied in molecular dynamics calculations of frictional force and energy and are compared to the results of atomic force microscope (AFM) measurements. In a second paper a team of researchers from the Institute of Physics at the University of Basel gives an update on Friction Force Microscopy (FFM). The authors also report experiments on dry mica and magneto optical disks, and of 2 and 4-molecular-layer soap films. A final group of three papers deal with computational and simulation techniques for atomic scale surface contacts. Ferrante and Bozzolo from NASA Lewis Research Center in Cleveland discuss the use of different potential functions (first principles compared BOOKS RECEIVED

The ARIANNA experiment seeks to observe the diffuse flux of neutrinos in the 10 8 − 10 10 GeV energy range using a grid of radio detectors at the surface of the Ross Ice Shelf of Antarctica. The detector measures the coherent Cherenkov radiation produced at radio frequencies, from about 100 MHz to 1 GHz, by charged particle showers generated by neutrino interactions in the ice. The ARIANNA Hexagonal Radio Array (HRA) is being constructed as a prototype for the full array. During the 2013-14 austral summer, three HRA stations collected radio data which was wirelessly transmitted off site in nearly real-time. The performance of these stations is described and a simple analysis to search for neutrino signals is presented. The analysis employs a set of three cuts that reject background triggers while preserving 90% of simulated cosmogenic neutrino triggers. No neutrino candidates are found in the data and a model-independent 90% confidence level Neyman upper limit is placed on the all flavor ν +ν flux in a sliding decade-wide energy bin. The limit reaches a minimum of 1.9×10 −23 GeV −1 cm −2 s −1 sr −1 in the 10 8.5 − 10 9.5 GeV energy bin. Simulations of the performance of the full detector are also described. The sensitivity of the full ARIANNA experiment is presented and compared with current neutrino flux models.

The ARIANNA hexagonal radio array (HRA) is an experiment in its pilot phase designed to detect cosmogenic neutrinos of energies above 10 16 eV. The most neutrino-like background stems from the radio emission of air showers. This article reports on dedicated efforts of simulating and detecting the signals of cosmic rays. A description of the fully radio self-triggered data-set, the properties of the detected air shower signals in the frequency range of 100-500 MHz and the consequences for neutrino detection are given. 38 air shower signals are identified by their distinct waveform characteristics, are in good agreement with simulations and their signals provide evidence that neutrino-induced radio signals will be distinguishable with high efficiency in ARIANNA. The cosmic ray flux at a mean energy of 6.5 +1.2 −1.0 × 10 17 eV is measured to be 1.1 +1.0 −0.7 × 10 −16 eV −1 km −2 sr −1 yr −1 and one five-fold coincident event is used to illustrate the capabilities of the ARIANNA detector to reconstruct arrival direction and energy of air showers.

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The move toward dense wavelength-division-multiplexed networks provides an application-rich environment for MEMS components and systems. In many crucial component applications, there are no clear technological winners, leaving room for new technologies such as MEMS to create inroads. In this paper, wavelength-division-multiplexed networks and their evolution are discussed and examples of several MEMS devices being developed for telecommunication systems are presented.

We demonstrate integration of GaAs-AIGaAs multiple quantum well modulators to silicon CMOS circuitry via flipchip solder-bonding followed by substrate removal. We obtain $J.5~0 device yield for 32 x 32 arrays of devices with 15 micron solder pads. We show operation of a simple circuit composed of a modulator and a CMOS transistor.

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