[en] Fermilab is in the process of upgrading its Booster Correction Element System to include full field correction element magnets to correct position and chromaticity throughout the booster cycle. This upgrade requires power supplies with maximum outputs of ±180V/±65A, with current bandwidths of 5k Hz and with slew rates of min to max current in 1ms. For seamless operation around zero current and voltage, we use continuous switching on both sides of the bridge. Although the straightforward way of coordinating the switching on both sides of the bridge can be accomplished with one triangle timing wave and one voltage reference, we have found that using two triangle waves yields a switching coordination that effectively doubles the frequency of the differential ripple on the load and allows for better filtering of the output ripple

[en] Fermilab is in the process of upgrading its Booster Correction Element System to include full field correction element magnets to correct position and chromaticity throughout the booster cycle. For good reliability of the switchmode power supplies designed to power the magnets, it is important to limit both the maximum temperature and the repetitive temperature cycling of the silicon junctions of the switching elements. We will describe how we measured these parameters and the results of our measurements

[en] The renewed interest for using wind energy commercially is not more than twenty-five years old. From an experimental stage of turning wind energy into electricity in the 1970s, a new industry for producing standardised windmills gained foothold in the beginning of the 1980s and since then it has developed rapidly through the 1980s and the 1990s. The Danish innovators of the new windmill technology have been the pioneers behind this development, and Denmark has succeeded in acquiring a first mover advantage on the world market. This position has been maintained and at present Denmark satisfies more than half of the world market's demand for windmills. There are at least two reasons for this pioneering position of the Danish windmill industry. First, Denmark is by nature very 'abundant' in wind energy due to its geographical position at the nexus between the Gulf Stream and the European continent. The windy climate makes given technologies of windmills more productive. Secondly, the production of electricity from wind power has been subsidised by state aid schemes among which the most important one has been a price guarantee per produced kWh (kilowatt-hours) to the owners of windmill. These subsidies have made production of electricity from windmills profitable for private investors and hence competitive on the market for electricity produced by fossil fuel. Although the public subsidies to produced electricity from wind power in Denmark have been motivated by environmental concerns over the emission of carbon dioxide (CO₂) from power plants using fossil fuels, the subsidies have resulted in the development of a new industry with a strong export performance. The development of the windmill industry thus illustrates an infant industry strategy where state aid in the upstart phase results in a build up of an internationally competitive industry in the long run. This is the Mill's test of an infant industry strategy. However, a precondition for a successful outcome of such a strategy is the existence of dynamic economies of scale or learning-by-doing within the industry so that the initial infant costs could be paid back later. This is the Bastable's test of an infant industry strategy. The purpose of this paper is to discuss, analyse and evaluate the welfare effects of the Danish policy measures for the windmill industry in order to conclude whether the intervention passes both the Mill's and the Bastable's tests. The paper is organised as follows. Section 2 introduces the available data on the remarkable development of the Danish windmill industry and presents the evidence of learning-by-doing in this industry. This section is based on the results of a previous analysis of the authors of the technological development in the windmill industry in Denmark. Section 3 gives an evaluation of the costs and benefits in an infant industry perspective and section 4 concludes the paper. (au)

[en] Vinyl Ester Styrene (VES) and Advanced Polymer Solidification (APS^TM) processes are used to solidify, stabilize, and immobilize radioactive, pyrophoric and hazardous wastes at US Department of Energy (DOE) and Department of Defense (DOD) sites, and commercial nuclear facilities. A wide range of projects have been accomplished, including in situ immobilization of ion exchange resin and carbon filter media in decommissioned submarines; underwater solidification of zirconium and hafnium machining swarf; solidification of uranium chips; impregnation of depth filters; immobilization of mercury, lead and other hazardous wastes (including paint chips and blasting media); and in situ solidification of submerged demineralizers. Discussion of the adaptability of the VES and APS^TM processes is timely, given the decommissioning work at government sites, and efforts by commercial nuclear plants to reduce inventories of one-of-a-kind wastes. The VES and APS^TM media and processes are highly adaptable to a wide range of waste forms, including liquids, slurries, bead and granular media; as well as metal fines, particles and larger pieces. With the ability to solidify/stabilize liquid wastes using high-speed mixing; wet sludges and solids by low-speed mixing; or bead and granular materials through in situ processing, these polymer will produce a stable, rock-hard product that has the ability to sequester many hazardous waste components and create Class B and C stabilized waste forms for disposal. Technical assessment and approval of these solidification processes and final waste forms have been greatly simplified by exhaustive waste form testing, as well as multiple NRC and CRCPD waste form approvals. (authors)

[en] Presently, there are 6 proton and 6 antiproton bunches used for collider operation in the Fermilab Tevatron. As the number of particles in these bunches increases, experimenter's detectors begin to saturate. To alleviate this situation, protons and antiprotons will be redistributed in 36 bunches instead of 6 to reduce the number of interactions per crossing. In order to carry this out, the rise and fall times of the Tevatron antiproton injection kicker which deflects the antiprotons onto the closed orbit must be reduced to accommodate the increased number of bunches circulating in the machine. To meet these criteria, it is necessary to reduce the inductance per unit length as seen by the driving source in order to achieve the necessary propagation time through the magnet, For a given aperture, this can be readily done using a picture frame design powered with two pulses of opposite polarity. Two magnets are required, each with a magnetic length of 2.41 m

[en] Ceramic beam tubes are utilized in numerous kicker magnets in different accelerator rings at Fermi National Accelerator Laboratory. Kovar flanges are brazed onto each beam tube end, since kovar and high alumina ceramic have similar expansion curves. The tube, kovar flange, end piece, and braze foil (titanium/incusil) alloy brazing material are stacked in the furnace and then brazed in the furnace at 1000 C. The ceramic specified is 99.8% Alumina, Al₂O₃, a strong recrystallized high-alumina fabricated by slip casting. Recent experience at Fermilab with the fabrication and brazing of these tubes has brought to light numerous problems including tube breakage and cracking and also the difficulty of brazing the tube to produce a leak-tight joint. These problems may be due to the ceramic quality, voids in the ceramic, thinness of the wall, and micro-cracks in the ends which make it difficult to braze because it cannot fill tiny surface cracks which are caused by grain pullout during the cutting process. Solutions which are being investigated include lapping the ends of the tubes before brazing to eliminate the micro-cracks and also metallization of the tubes

[en] This is a companion paper to the Hughes/Edwards paper presented at EPRI '96, entitled open-quotes Don't Put Your Troubles Down the Drain.close quotes That paper presents a detailed account of liquid radwaste processing performance at Texas Utilities' Comanche Peak Steam Electric Station from 1993 to 1995. This paper looks at the same period from a historical and philosophical (and subjective) perspective

[en] The report summarizes the remedial measurements carried out under the National Action Plan against Cancer in Norway in the period 1999-2003.The cost effectiveness of the state subsidized remedial measures against radon is evaluated. Other measurements under the National Action Plan against Cancer have also been evaluated, such as measurements of radon in 38.000 dwellings in 158 municipalities, information measures, and actions to increase radon mitigation competence in the building construction industry and in the municipalities. (Author)

[en] The use of evaporators to process PWR radwaste water is wide spread. Recent technical as well as economic forces have driven a growing number of utilities to ion exchange. This paper summarizes the experience of four PWRs that made the switch from evaporators to sluicable demineralization systems for low-level radwaste water treatment. In addition to increasing water processing rates and eliminating overall down-time due to evaporator maintenance, the demin system reduced personnel exposure by 80 - 93% and reduced total burial volume by 75 - 95%. Cost reductions directly attributable to the switchover ranged from 33 to 77% of evaporator processing costs

[en] As part of the Fermilab Tevatron upgrade, a 6.25Ω ferrite loaded traveling wave kicker magnet has been designed. The critical parameters are the field rise time and flatness during and after the pulse. A picture frame pole piece configuration was chosen which requires two pulses of equal amplitude but opposite polarity. Low inductance, high voltage capacitors placed between each of the pole pieces provide the shunt reactance necessary to achieve the 6.25Ω impedance. Cross coupling adjacent cells is used to improve the transient response of the magnet. The compensated termination resistors are built into the magnet to minimize reflections. Two spark gap pulsers provide the two 4800A fast rise time current pulses necessary to drive this magnet. The field in this 2.4 m long magnet rises to 1055G in less than 400 ns. This paper describes the design choices involved with this system and preliminary test results