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The implications of potential `lock-in` markets for renewable energy

Description: Nonlinear economic effects can cause unpredictable and sometimes undesirable outcomes in the marketplace. Increasing returns can lead to self-reinforcing situation in which increasing market share lead to a more attractive product, which leads in turn to further increases in market share. This results in ``lock-in`` of a technology, which cannot be overcome except by a significant shift in technology, consumer tastes, or other market factors.
Date: November 1, 1996
Creator: Cowan, R. & Kline, D.
Partner: UNT Libraries Government Documents Department

High-Frequency and Very-high-Frequency (HF&VHF) above-groundelectromagnetic impedance measurements

Description: We have field-tested an apparatus for measuring the electromagnetic impedance above the ground at a plurality of frequencies in the 0.3 - 30 MHz range. This window in the frequency spectrum, which lies between frequencies used for GPR and those used for conventional loop-loop EM soundings, has not been used because of difficulties in fielding equipment for making absolute and accurate measurements. Model and physical parameter studies however confirm that data in this frequency band can be used to construct high-resolution maps of electrical conductivity and permittivity of near-surface material. Our equipment was assembled using commercial electric and magnetic antennas. The magnetic loop source is excited by a conventional signal generator - power amplifier assembly. Signal detection is accomplished using RF lock-in amplifiers. All system elements are appropriately isolated by optic - fiber links. We estimate a measurement accuracy of about {+-} 10% for an 8-m separation between source and detector. Field tests were done at the University of California Richmond Field Station where the near surface electrical structure is well known. The experimental data at this site are mainly a function of electrical conductivity. In this context, we have obtained good agreement with the known local variations in resistivity both with depth and with position along a 35-m traverse. Additional tests in more resistive regimes where dielectric permittivity is not negligible yield spectral data compatible with the less well known near-surface electrical properties.
Date: September 20, 2002
Creator: Frangos, William; Becker, Alex & Lee, K.H.
Partner: UNT Libraries Government Documents Department

MONITORING POWER PLANT EFFICIENCY USING THE MICROWAVE-EXCITED PHOTOACOUSTIC EFFECT TO MEASURE UNBURNED CARBON

Description: Three test instruments are being evaluated to determine the feasibility of using photoacoustic technology for measuring unburned carbon in fly ash. The first test instrument is a single microwave frequency system previously constructed to measure photoacoustic signals in an off-line configuration. A second off-line instrument was constructed based in part on lessons learned with the first instrument, but which also expands the capabilities of the first instrument. Improvements include a control loop to allow more constant microwave power output and an ability to operate over a range of microwave frequencies. The third instrument, the on-line version of the fly ash monitor, has been designed, constructed, and initial efficiency tests have been conducted on the monitor's electrical components. This quarter focused on improving the signal strength of the accelerometer by increasing the power level of the microwaves that induced the thermo-elastic effect, and also to conduct repeatability experiments. Efforts this quarter were spent improving the coupling of the accelerometer with the diaphragm, detecting and eliminating microwave leakage, isolating stray electrical current within the laboratory, specifically within the ground, and replacing a faulty lock-in amplifier.
Date: July 1, 2004
Creator: Brown, Robert C.; Weber, Robert J. & Sweterlitsch, Jeff
Partner: UNT Libraries Government Documents Department

Fissile and Non-Fissile Material Detection using Nuclear Acoustic Resonance Signatures

Description: This report reviews progress made on NA22 project LL251DP to develop a novel technique, Nuclear Acoustic Resonance (NAR), for remote, non-destructive, nonradiation-based detection of materials of interest to Nonproliferation Programs, including {sup 235}U and {sup 239}Pu. We have met all milestones and deliverables for FY05, as shown in Table 1. In short, we have developed a magnetic shield chamber and magnetic field, develop a digital lock-in amplifier computer to integrate both the ultrasound radiation with the detector, developed strain measurements, and begin to perform initial measurements to obtain a NAR signal from aluminum at room temperature and near the earth's magnetic field. The results obtained in FY05 further support the feasibility of successful demonstration of an NAR experiment for remote, non-destructive, non-radiation-based detection of materials of interest to Nonproliferation Programs.
Date: October 4, 2005
Creator: Herberg, J; Maxwell, R; Tittmann, B R; Lenahan, P M; Yerkes, S & Jayaraman, S
Partner: UNT Libraries Government Documents Department

Fissile and Non-Fissile Material Detection using Nuclear Acoustic Resonance Signatures: Final Report

Description: This is final report on NA-22 project LL251DP, where the goal was to develop a novel technique, Nuclear Acoustic Resonance (NAR), for remote, non-destructive, nonradiation-based detection of materials of interest to Nonproliferation Programs, including {sup 235}U and {sup 239}Pu. In short, we have developed a magnetic shield chamber and magnetic field, develop a digital lock-in amplifier computer to integrate both the ultrasound radiation with the detector, developed strain measurements, and begun to perform initial measurements to obtain a NAR signal from aluminum at room temperature and near the earth's magnetic field. Since our funding was cut in FY06, I will discuss where this project can go in the future with this technology.
Date: November 2, 2006
Creator: Herberg, J; Maxwell, R; Tittmann, B R; Lenahan, P M; Yerkes, S & Jayaraman, S B
Partner: UNT Libraries Government Documents Department

A Proposed Fast Luminosity Feedback for the Super-B Accelerator

Description: We present a possible design for a fast luminosity feedback for the SuperB Interaction Point (IP). The design is an extension of the fast luminosity feedback installed on the PEP-II accelerator. During the last two runs of PEP-II and BaBar (2007-2008), we had an improved luminosity feedback system that was able to maintain peak luminosity with faster correction speed than the previous system. The new system utilized fast dither coils on the High-Energy Beam (HEB) to independently dither the x position, the y position and the y angle at the IP, at roughly 100 Hz. The luminosity signal was then read out with three independent lock-in amplifiers. An overall correction was computed based on the lock-in signal strengths and beam corrections for position in x and y and in the y angle at the IP were simultaneously applied to the HEB. With the 100 times increase in luminosity for the SuperB design, we propose using a similar fast luminosity feedback that can operate at frequencies between DC and 1 kHz, high enough to follow any beam motion from the final focusing magnets.
Date: May 15, 2009
Creator: Bertsche, Kirk; Field, R.Clive; Fisher, Alan; Sullivan, Michael; /SLAC; Drago, Alessandro et al.
Partner: UNT Libraries Government Documents Department

A Prototype Wire Position Monitoring System

Description: The Wire Position Monitoring System (WPM) will track changes in the transverse position of LCLS Beam Position Monitors (BPMs) to 1{micro}m over several weeks. This position information will be used between applications of beam based alignment to correct for changes in component alignment. The WPM system has several requirements. The sensor range must be large enough so that precision sensor positioning is not required. The resolution needs to be small enough so that the signal can be used to monitor motion to 1{micro}m. The system must be stable enough so that system drift does not mimic motion of the component being monitored. The WPM sensor assembly consists of two parts, the magnetic sensor and an integrated lock-in amplifier. The magnetic sensor picks up a signal from the alternating current in a stretched wire. The voltage v induced in the sensor is proportional to the wire displacement from the center of the sensor. The integrated lock-in amplifier provides a DC output whose magnitude is proportional to the AC signal from the magnetic sensor. The DC output is either read on a digital voltmeter or digitized locally and communicated over a computer interface.
Date: December 7, 2010
Creator: Wang, Wei
Partner: UNT Libraries Government Documents Department

Pressure Broadening of Single Vibrational-Rotational Transitions of Acetylene AT v = 5

Description: To understand the mechanism of pressure broadening one must have accurate values of the pressure broadening coefficients as a function of vibrational quantum number. Unfortunately, such data for polyatomic molecules are scarce. The coefficient for self-broadening of methane has been found to be the same for the R(0) and R(1) lines of the 2{nu}{sub 3} and 3{nu}{sub 3} bands and for an unidentified line of the 5{nu}{sub 1} + {nu}{sub 3} band at 6190 {angstrom} (1). Measurements have also been performed on the {nu}{sub 2} (2) and {nu}{sub 1} + {nu}{sub 3} (3) bands of acetylene. In the work described here, high resolution spectra of single vibrational-rotational lines of the 5{nu}{sub 3} band of acetylene at 15,600 cm{sup -1} have been taken to determine the coefficients for self-broadening at a much higher level of vibrational excitation. A single frequency cw dye laser (Spectra-Physics 580A) with Rhodamine B as the lasing medium is used as a narrow bandwidth light source. The laser is continuously scannable over a 10 GHz region with 30 MHz linewidth. The unfocused beam is chopped and directed through a small, nonresonant optoacoustic cell. The pressure of the acetylene (> 99.99% purity) in the cell is measured with a capacitance manometer. The optoacoustic signal is detected by a miniature electret microphone placed within the cell and is processed by a lock-in amplifier. The high resolution scans are calibrated ({+-} 5%) by monitoring the dye laser output with a spectrum analyzer equipped with 2 GHz FSR mirrors. All spectra were taken at room temperature (293 {+-} 2 K). At the relatively low pressures used in these experiments, the experimental linewidths are not more than three times the Doppler width (1.1 GHz FWHM). The method of Gronwall was used to calculate values of the Voigt lineshape. With these data, the ...
Date: February 1, 1980
Creator: Wong, James S.
Partner: UNT Libraries Government Documents Department