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in subjects: "Hz Range"

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The design and operation of infrasonic microphones

This report is intended as a guide to the design and operation of infrasonic microphones. It will emphasize general principles and the effects of parameter choices upon performance but will not provide details of design for specific microphones. The report will consider primarily the mechanical aspects that control the acoustic properties; it will not discuss the features of electronic design, which vary greatly among microphones. Here the authors define infrasonic microphones as sensors capabl… more

Date: May 1, 1997

Creator: Mutschlecner, J.P. & Whitaker, R.W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Evaluation of signal processing techniques for the analysis of large civil structures.

Several new methods of determining change in the data signature of a large Cable-Stayed bridge are examined and compared. Two sets of data, one taken in September 1995, and the second in June 2000 are studied. Structural changes are investigated using several techniques; (1) Modal behavior in the .3 to 3 Hz range is investisated using Transmissibility FRFs and the Random Decrement Method, (2) Quasi Periodic behavior in the 3 to 30 Hz frequency range is observed in several tests. Potential cause… more

Date: January 1, 2001

Creator: Hunter, N. F. (Norman F.) & Schultze, J. F. (John F.)

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Nonlinear whistler wave scattering in space plasmas

In this paper the evolution of nonlinear scattering of whistler mode waves by kinetic Alfven waves (KAW) in time and two spatial dimensions is studied analytically. The authors suggest this nonlinear process as a mechanism of kinetic Alfven wave generation in space plasmas. This mechanism can explain the dependence of Alfven wave generation on whistler waves observed in magnetospheric and ionospheric plasmas. The observational data show a dependence for the generation of long periodic pulsation… more

Date: April 1, 1997

Creator: Yukhimuk, V. & Roussel-Dupre, R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Energy scavenging from environmental vibration.

The goal of this project is to develop an efficient energy scavenger for converting ambient low-frequency vibrations into electrical power. In order to achieve this a novel inertial micro power generator architecture has been developed that utilizes the bi-stable motion of a mechanical mass to convert a broad range of low-frequency (< 30Hz), and large-deflection (>250 {micro}m) ambient vibrations into high-frequency electrical output energy. The generator incorporates a bi-stable mechanic… more

Date: October 1, 2009

Creator: Galchev, Tzeno (University of Michigan); Apblett, Christopher Alan & Najafi, Khalil (University of Michigan)

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

On the Choice of Method to Cancel 60 Hz Disturbances in Beam Position and Energy

Because the voltage applied to magnets in accelerators is likely to be rectified, there can be 60 Hz related fluctuations in beam position and energy. Correcting such errors as well as other less repeatable errors can be done with combinations of feedback, feedforward, real time repetitive control, and batch update repetitive control. This paper studies how to mix these approaches for optimized performance. It is shown that use of feedback control can be counterproductive because of the waterbe… more

Date: June 1, 2001

Creator: Akogyeram, R.A.; Longman, R.W.; Hutton, Andrew & Juang, J.-N.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Force measurements during vibration testing

Experimental measurements of force into a ``rigid`` test item representing a typical system level vibration test were conducted to evaluate several methods of force measurements. The methods evaluated included: (1) Direct measurement with force gages between the test item and the fixturing; (2) Measurement of the force at the shaker/fixture interface and correcting the force required to drive the fixturing using two methods, (a) mass subtraction and (b) SWAT (sum of weighted accelerations techn… more

Date: December 31, 1993

Creator: Smallwood, D. O. & Coleman, R. G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Electromagnetic method for analyzing the property of steel casing

It has been shown that electromagnetic (EM) imaging, in particular in borehole applications, can be effective in characterizing and monitoring subsurface processes involved in improved oil recovery operations and production management. In this report the authors present an innovative EM method for extracting information about a steel casing in terms of its electrical conductivity, magnetic permeability, and the casing thickness. The method is based on accurate evaluation of magnetic fields near… more

Date: February 1, 1998

Creator: Lee, K. H.; Kim, H. J. & Song, Y.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Surveillance of 18 Hz and 60 Hz components of ground motion at the APS site

The objectives of this study are to determine the location and source of the 18- and 60-Hz vibration and to eliminate or reduce its amplitude in the APS Facility. To accomplish this it is necessary to know the time of occurrence and then, to utilize triangulation methods to identify the location of the source. It its time sequence is known, it may be possible to correlate it with the operation of some equipment at or near the site. Therefore, a major effort was made to obtain the time sequence … more

Date: March 1, 1990

Creator: Jendrzejczyk, J. A.; Wambsganss, M. W. & Smith, R. K.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

60 HZ beam motion reduction at NSLS UV storage ring

A significant reduction in 60 hz beam motion has been achieved in the UV storage ring. From the wide band harmonic beam motion signal, 60 hz signal is extracted by tuned bandpass filter. This signal is processed by the phase and amplitude adjustment circuits and then, it is fed into the harmonic orbit generation circuits. Several harmonics, near the tune, were canceled by employing one circuit for each harmonic. The design and description of this experiment is given in this paper. The results s… more

Date: January 1, 1997

Creator: Singh, O. V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Office worker exposure to extremely low frequency magnetic fields

A study of office worker exposure to extremely low frequency magnetic fields (ELF MF) was conducted at Los Alamos National Laboratory. The main purpose of this study was to quantitatively assess ELF MF exposures. A secondary objective was to determine whether or not exposures to ELF MF can be reduced by implementing administrative controls and educating workers on the sources of such fields. EMDEX dosimeters were used to determine full shift personal exposures for 12 volunteers from two personn… more

Date: May 1, 1994

Creator: Hiebert, D. G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

LFSC - Linac Feedback Simulation Code

The computer program LFSC (<Linac Feedback Simulation Code>) is a numerical tool for simulation beam based feedback in high performance linacs. The code LFSC is based on the earlier version developed by a collective of authors at SLAC (L.Hendrickson, R. McEwen, T. Himel, H. Shoaee, S. Shah, P. Emma, P. Schultz) during 1990-2005. That code was successively used in simulation of SLC, TESLA, CLIC and NLC projects. It can simulate as pulse-to-pulse feedback on timescale corresponding to 5-100… more

Date: May 1, 2008

Creator: Ivanov, Valentin

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Running the AGS MMPS at 5 HZ, 24 GEV

The Brookhaven Alternating Gradient Synchrotron (AGS) is a strong focusing accelerator which is used to accelerate protons and various heavy ion species to an equivalent proton enera of 29 GeV. At this energy, the maximum intensity achieved is 7 x 10{sup 13} protons per pulse. This corresponds to an average beam power of about 0.2 MW. Future programs in high-energy and neutron physics may require an upgrade of the AGS accelerator to an average beam power of around 4 MW, with proton beams at the… more

Date: June 18, 2001

Creator: Marneris, I.; Roser, T.; Ruggiero, A. G. & Sandberg, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Magnetotelluric investigations at the Roosevelt Hot Springs KGRA and Mineral Mountains, Utah. Topical report 78-1701. a. 6. 1

Twenty-five magnetotelluric (MT) sites were monitored. Amongst other MT functions, the transverse electric (TE) and transverse magnetic (TM) apparent resistivity and impedance phase data were provided for the frequency range 3 x 10/sup -3/ Hz to 100 Hz. Some one-dimensional inversion results for this area yielded very low values of estimated true resistivity. Such values are unrealistic in light of established notions about conductivity mechanisms in earth materials. Furthermore, the assembly o… more

Date: January 1, 1978

Creator: Wannamaker, P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Discriminating ripple-fire explosions with high frequency (>20 Hz) data

With a Comprehensive Test Ban (CTB), discriminating ripple-fired explosions from mining operations becomes important. Different methods have been proposed to discriminate these explosions, most of which use the modulations seen in the spectra of ripple-fired blasts. The Deployable Seismic Verification System (DSVS) in Wyoming records data at frequencies up to 50 Hz, and provides an opportunity to determine if there are any operational benefits to discriminate ripple-fired explosions from using … more

Date: April 1, 1996

Creator: Carr, D. B. & Garbin, H.D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Applications and source development for high-repetition rate x-ray lasers

Many applications in material science, chemistry, and atomic physics require an x-ray source that has a repetition rate of 1 Hz to a few kHz. In these fields, a very wide range of photon energies is of interest. One application is time-resolved surface photoelectron spectroscopy and microscopy where low energy (< 1{mu}J) pulses are required to avoid space charge effects but high-repetition rates ({approx} kHz) provide the high average power which is needed to obtain the desired resolution. In p… more

Date: July 30, 1993

Creator: Eder, D. C.; Amendt, P. & Bolton, P. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Response of the rf-extraction-wing balcony and floor, and the storage ring to forced and ambient vibration excitation and coupling to tunnel/basemat

To ensure successful operation of the APS, vibration of the storage ring quadrupole magnets must be limited to very low levels for frequencies >10 Hz. There will be many sources of vibration, such as pumps, fans, compressors, generators, and other rotating and reciprocating machinery when the APS is operational. In general, such vibration sources are isolated from the structural components and base foundations by vibration dampers and isolators. Pumps are typically mounted on seismic isolators,… more

Date: August 1, 1993

Creator: Jendrzejczyk, J. A.; Wambsganss, M. W.; Smith, R. K. & Rosas-Velez, P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Surveillance of 18 Hz and 60 Hz components of ground motion at the APS site

Date: March 1, 1990

Creator: Jendrzejczyk, J.A.; Wambsganss, M.W. & Smith, R.K.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

ELF electric and magnetic fields: Pacific Northwest Laboratory studies

Studies have been conducted at Battelle, Pacific Northwest Laboratory, to examine extremely-low-frequency (ELF) electromagnetic fields for possible biological effects in animals. Three areas of investigation are reported here: (1) studies on the nervous system, including behavior and neuroendocrine function, (2) experiments on cancer development in animals, and (3) measurements of currents and electric fields induced in animal models by exposure to external magnetic fields. In behavioral experi… more

Date: June 1, 1992

Creator: Anderson, L. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Analysis spectral shapes from California and central United States ground motion

The objective of this study is to analyze the spectral shapes from earthquake records with magnitudes and distances comparable to those that dominate seismic hazard at Oak Ridge, in order to provide guidance for the selection of site-specific design-spectrum shapes for use in Oak Ridge. The authors rely heavily on California records because the number of relevant records from the central and eastern United States (CEUS) is not large enough for drawing statistically significant conclusions. They… more

Date: January 24, 1994

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Ripple Filter for the 10,000A Superconducting Magnet Test Stand at the Magnet Test Facility

The new 10,000A dumpswitch [1] and dumpresistor [2] system at MTF required a 720Hz filter to eliminate power supply ripple from the load. The new filter, shown in Figure 1, had two requirements: (1) Less then 1/2 Ap-p ripple current with a load current of 10,000A; (2) No or minimal overshoot when the current reaches flattop after it is ramped to 10,000A. MFT magnets are ramped to their final current values at different ramp rates depending on the inductance and type of the magnet under test. Th… more

Date: November 1991

Creator: Drennan, E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Sonic enhanced ash agglomeration and sulfur capture. Quarterly report, January 1996--March 1996

A major concern with the utilization of coal in directly fired gas turbines is the control of particulate emissions and reduction of sulfur dioxide, and alkali vapor from combustion of coal, upstream of the gas turbine. Much research and development has been sponsored on methods for particulate emissions control and the direct injection of calcium-based sorbents to reduce SO{sub 2} emission levels. The results of this research and development indicate that both acoustic agglomeration of particu… more

Date: April 1, 1996

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Multiparameter data acquisition and display program. [MUL, DREF, DUPD]

A general-purpose multiparameter data acquisition, histo-gramming, and display program is presented. The 32 input parameters of the program consist of up to 16 CAMAC words of 16 bits, and up to 16 algebraic functions of these words. Up to 64 one- and two-dimensional histograms based on these parameters can be constructed, subject to up to 144 correlated conditions imposed on the input parameters. The display system consists of a rapid refresh scope with 10-bit X and Y resolution and a push-bott… more

Date: January 1, 1979

Creator: Sunier, J. W.; Poore, R. V. & McMillan, D. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Impedance measurements on sealed lead--acid cells. [2. 5 Ah, 10 Hz to 500 kHz]

The impedance of sealed 2.5-ampere-hour lead--acid cells was measured as a function of state of charge at frequencies of 10 Hz to 500 kHz. The impedance of a small lead--acid wet cell employing flat-plate electrodes was also measured over this frequency range. Comparisons between the results for these two cell types indicate that impedances are sensitive to chemical and physical changes which accompany cell discharge. A model is proposed which relates inductive behavior for porous electrodes to… more

Date: May 10, 1978

Creator: Martinelli, M. R. & Zimmerman, A. H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Lead acid battery pulse discharge investigation. Final report

The effects of high current pulses caused by electric vehicle silicon-controlled rectifier and transistor chopper controllers on battery energy, lifetime, and microstructure were studied. Test equipment and results are described. It was found that the energy of improved golf cart-type batteries deteriorated under pulsed conditions by about 10% with respect to dc conditions for pulses between 16 and 333 Hz - no difference was noted above 333 Hz. Frequencies and duty cycles characteristic of elec… more

Date: April 1, 1980

Creator: Dowgiallo, E

Item Type: Report

Partner: UNT Libraries Government Documents Department