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The force exerted on the rotor by an active magnetic bearing (AMB) is determined by the current flow in the magnet coils. This force can be controlled very precisely, making magnetic bearings a potential benefit for grinding, where cutting forces act as external disturbances on the shaft, resulting in degraded part finish. It is possible to achieve precise shaft positioning, reduce vibration of the shaft caused by external disturbances, and even damp out resonant modes. Adaptive control is an appealing approach for these systems because the controller can tune itself to account for an unknown periodic disturbance, such as cutting or grinding forces, injected into the system. In this paper the authors show how one adaptive control algorithm can be applied to an AMB system with a periodic disturbance applied to the rotor. An adaptive algorithm was developed and implemented in both simulation and hardware, yielding significant reductions in rotor displacement in the presence of an external excitation. Ultimately, this type of algorithm could be applied to a magnetic bearing grinder to reduce unwanted motion of the spindle which leads to poor part finish and chatter.

The major consumer electronics in U.S. homes accounted for over 10 percent of U.S. residential electricity consumption, which is comparable to the electricity consumed by refrigerators or lighting. We attribute 3.6 percent to video products, 3.3 percent to home office equipment, and 1.8 percent to audio products. Televisions use more energy than any other single product category, but computer energy use now ranks second and is likely to continue growing. In all, consumer electronics consumed 110 THw in the U.S. in 1999, over 60 percent of which was consumed while the products were not in use.

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The idea of producing beams of high energy photons by Compton backscattering of laser photons was proposed over 20 years ago. At the time, producing the required laser pulses was not feasible. However, recent advances in high average power, diode pumped lasers appear to have solved this problem. The US Collaboration is now turning its attention to the engineering requirement of mating the laser and optics components with the accelerator structures in the confined space of the a colliding beam interaction region. The demonstration of a technically feasible interaction region design is planned for the Snowmass conference in 2001.

All the process elements are commercially available to operate coal gasification so that it can produce electricity, hydrogen, and carbon dioxide while delivering the same quantity of power as without H{sub 2} and CO{sub 2} recovery. To assess the overall impact of such a scheme, a full-energy cycle must be investigated (Figure 1). Figure 2 is a process flow diagram for a KRW oxygen-blown integrated gasification combined-cycle (IGCC) plant that produces electricity, H{sub 2}, and supercritical CO{sub 2}. This system was studied in a full-energy cycle analysis, extending from the coal mine to the final destination of the gaseous product streams [Doctor et al. 1996, 1999], on the basis of an earlier study [Gallaspy et al. 1990]. The authors report the results of updating these studies to use current turbine performance.

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In December 1998, the Institute of Electrical and Electronic Engineers (IEEE) began writing a standard for the interconnection of distributed resources with electric power systems. This standard will prescribe technical requirements for the interconnection of distributed resources that are connected to primary or secondary voltages in electric distribution systems. It is expected to play a significant role in facilitating a new, emerging market for small, distributed, primarily gas-fired electric generators, including new technologies such as fuel cells and micro-turbines. Once published, this new standard will be enforced for the interconnection of distributed wind power applications, as well. The co-authors of this paper have been active with this standard from the beginning, focusing on issues most likely to affect interconnection of wind power. This paper describes the standard-writing process and highlights technical issues critical to wind power, with the intent of soliciting feedback from an encouraging broader participation by the wind industry.

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We review the status of two ongoing large-scale searches for axions which may constitute the dark matter of our Milky Way halo. The experiments are based on the microwave cavity technique proposed by Sikivie, and marks a ''second-generation'' to the original experiments performed by the Rochester-Brookhaven-Fermilab collaboration, and the University of Florida group.

In this paper the authors demonstrate through calculations and theoretical analysis the first application of a x-ray laser for probing hot, high-density plasmas (n{sub e} {ge} 10{sup 23} cm{sup -3}) using a Ni-like transient collisional excitation x-ray laser as a probe. Theoretical predictions are used to diagnose the electron temperature in short pulse (500 fs) laser produced plasmas. The threshold power of the x-ray probe is estimated by comparing theoretical scattering levels with plasma thermal emission. The necessary spectral resolution of the instrument sufficient for resolving electron temperature is given.

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We review the status of two ongoing large-scale searches for axions which may constitute the dark matter of our Milky Way halo. The experiments are based on the microwave cavity technique proposed by Sikivie, and marks a 'second-generation' to the original experiments performed by the Rochester-Brookhaven-Fermilab collaboration, and the University of Florida group.

The tropics are regions of strong ocean-atmosphere interaction on seasonal and interannual timescales, so a good representation of observed tropical behavior is a desirable objective for coupled ocean-atmosphere general circulation models (CGCMs). To broaden and update previous assessments (Mechoso et al. 1995, Neelin et al. 1992), two complementary projects were initiated by the CLIVAR Working Group on Seasonal to Interannual Prediction (WGSIP): the El Nino Simulation Intercomparison Project (ENSIP, by Mojib Latif) and STOIC (Study of Tropical Oceans In Coupled models). The aim was to compare models against observations to identify common weaknesses and strengths. Results from ENSIP concentrating on the equatorial Pacific have been described by Latif et al. (2000), hereafter ENSIP2000. A detailed report on STOIC is available via anonymous ftp at email.meto.gov.uk/pub/cr/ ''stoic'' and is summarized in Davey et al. (2000). The STOIC analyses extend beyond the equatorial Pacific, to examine behavior in all three tropical ocean regions.

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