Precision pulse-timing instrumentation for ultrasonic nondestructive testing (open access)

Precision pulse-timing instrumentation for ultrasonic nondestructive testing

A new, pulse-timing discriminator and B-scan time-to-pulse-height converter have been developed for the inspection of production parts. The discriminator is easy to operate and features automatic echo gating and automatic pulse polarity discrimination. This instrument combines the noise-blanking advantages of threshold discrimination with the echo-timing precision of zero-crossing discrimination to improve measurement accuracy by a factor of two over the best precious techniques. When used with the discriminator, the B-scan unit allows detection of flaws at depths less than one-fourth those obtainable with commercially available instruments. 3 refs., 20 figs., 2 tabs.
Date: August 31, 1990
Creator: Duncan, M. G.
Object Type: Report
System: The UNT Digital Library
A system architecture for long duration free floating flight for military applications (open access)

A system architecture for long duration free floating flight for military applications

Accessibility is today's space frontier. Our need for wide-band global communications, earth imaging an sensing, atmospheric measurements and military reconnaissance is endless but growing dependence on space-based systems raises concerns about potential vulnerability. Military commanders want space assets more accessible and under direct local control. As a result, a robust and low cost access to space-like capability has become a national priority. Buoyant vehicles, free floating in the middle stratosphere could provide the kind of cost effective access to space-like capability needed for a verity of missions. These vehicles are inexpensive, invisible and easily launched. Developments in payload electronics, atmospheric wind modeling and materials combined with ever-improving communications and navigation infrastructure are making balloon-borne concepts more attractive. The fundamental question is whether a free floating balloon, used in a pseudo-satellite role, has value in a military system. Flight tests are ongoing under NASA sponsorship. Following these tests NASA intends to use the vehicles for research in the Antarctic. The concept is being reviewed by other agencies interested in stratospheric research. We believe that LDFFF systems have applications in areas of communications, surveillance and other traditional satellite missions. Dialogue with the broader community of space users is needed to expand the …
Date: August 31, 1990
Creator: Epley, L.E. (CIRRUS Aerospace Corp., Burke, VA (USA))
Object Type: Report
System: The UNT Digital Library
(Hydrological and geochemical response and recovery in disturbed arctic ecosystems) (open access)

(Hydrological and geochemical response and recovery in disturbed arctic ecosystems)

Ionic concentration of snow prior to meltoff in 1990 as in previous years ranged widely from point to point within the basin. Overland flow began on May 12 and was monitored at closely-spaced time intervals for discharge volume and ionic concentrations to better define this relationship in non-channelized flow. Ionic concentration in both watertrack flow and in Imnavait Creek were closely monitored during meltoff. During the post melt period daily sampling was maintained in watertrack 7 and Imnavait Creek. Rainfall collection and analysis on an eight day schedule was maintained as in previous years. Soil solution composition was monitored on an event basis in conjunction with a similar schedule of precipitation sampling to determine relationships between precipitation and near surface and overland flow. Composition of deeper soil solution was also monitored and sampled for {sup 18}O analyses to determine the age structure of water contributed by the active layer to stream and watertracks. A pilot experiment employing salt tracers was conducted across landscape units to determine rates and pathways of soil solution movement in response to individual rain events. Nutrient addition in rime and fog were also recorded to add detail to the input side of the balance equation.
Date: August 31, 1990
Creator: Everett, K. R.
Object Type: Report
System: The UNT Digital Library
Geochemical and physical properties of soils and shallow sediments at the Savannah River Site (open access)

Geochemical and physical properties of soils and shallow sediments at the Savannah River Site

A program to characterize the geochemical and physical properties of the unimpacted soils and shallow sediments at the Savannah River Site (SRS) has been completed. The maximum, minimum, median, standard deviation, and mean values for metals, radionuclides, inorganic anions, organic compounds, and agricultural indicator parameters are summarized for six soil series that were identified as representative of the 29 soil series at SRS. The soils from unimpacted areas of SRS are typical of soils found in moderately aggressive weathering environments, including the southeastern United States. Appendix 8 organic compounds were detected in all samples. Since these constituents are not generally present in soil, this portion of the investigation was intended to assess possible laboratory artifacts. An additional objective of the SRS Soil Study was to determine if the composition of the split spoon sampler biased chemical analysis of the soils. Twenty-five duplicate samples were analyzed for a number of metals, radiological and agricultural parameters, and organics by two laboratories currently contracted with to analyze samples during waste site characterization. In all cases, the absolute values of the average differences are relatively small compared to the overall variability in the population. 31 refs., 14 figs., 48 tabs.
Date: August 31, 1990
Creator: Looney, B. B.; Eddy, C. A.; Ramdeen, M.; Pickett, J. (Savannah River Lab., Aiken, SC (USA)); Rogers, V. (Soil Conservation Service, Aiken, SC (USA). Savannah River Site Savannah River Lab., Aiken, SC (USA)); Scott, M. T. et al.
Object Type: Report
System: The UNT Digital Library
Measurement of the Portsmouth Gaseous Diffusion Plant criticality accident alarm (open access)

Measurement of the Portsmouth Gaseous Diffusion Plant criticality accident alarm

Measurements of the Portsmouth Gaseous Diffusion Plant's nuclear criticality accident radiation alarm signal response time, sound wave frequency, and sound volume levels were made to demonstrate compliance with ANSI/ANS-8.3-1986. A steady-state alarm signal is produced within one-half second of obtaining a two-out-of-three detector trip. The fundamental alarm sound wave frequency is 440 hertz. The sound volume levels are greater than 10 decibels above background and ranged from 100 to 125 A-weighted decibels. The requirements of the standard were met; however the recommended maximum sound volume level of 115 dBA was exceeded. Emergency procedures require immediate evacuation upon initiation of a facility's radiation alarm. Comparison with standards for allowable time of exposure at different noise levels indicate that the elevated noise level at this location does not represent an occupational injury hazard. 8 refs., 5 figs.
Date: August 31, 1990
Creator: Tayloe, R.W. Jr. (Battelle Columbus (USA)) & McGinnis, B. (Martin Marietta Energy Systems, Inc., Piketon, OH (USA))
Object Type: Report
System: The UNT Digital Library
Texas Attorney General Opinion: JM-1214 (open access)

Texas Attorney General Opinion: JM-1214

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Jim Mattox, regarding a legal question submitted for clarification: Whether the Texas Department of Health is required to inspect and license as a personal care home a boarding facility registered by the Department of Mental Health and Mental Retardation, and related questions (RQ-1974)
Date: August 31, 1990
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Texas Attorney General Opinion: JM-1215 (open access)

Texas Attorney General Opinion: JM-1215

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Jim Mattox, regarding a legal question submitted for clarification: Whether a commissioners court may prescribe a prevailing wage for certain contracts, and related questions (RQ-1977)
Date: August 31, 1990
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Texas Attorney General Opinion: LO90-60 (open access)

Texas Attorney General Opinion: LO90-60

Letter opinion issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Jim Mattox, regarding a legal question submitted for clarification.
Date: August 31, 1990
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Texas Register, Volume 15, Number [66], Pages 4986-5039, August 31, 1990 (open access)

Texas Register, Volume 15, Number [66], Pages 4986-5039, August 31, 1990

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: August 31, 1990
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Ambient Weather Model Research and Development: Final Report. (open access)

Ambient Weather Model Research and Development: Final Report.

Ratings for Bonneville Power Administration (BPA) transmission lines are based upon the IEEE Standard for Calculation of Bare Overhead Conductor Temperatures and Ampacity under Steady-State Conditions (1985). This steady-state model is very sensitive to the ambient weather conditions of temperature and wind speed. The model does not account for wind yaw, turbulence, or conductor roughness as proposed by Davis (1976) for a real time rating system. The objective of this research has been to determine (1) how conservative the present rating system is for typical ambient weather conditions, (2) develop a probability-based methodology, (3) compile available weather data into a compatible format, and (4) apply the rating methodology to a hypothetical line. The potential benefit from this research is to rate transmission lines statistically which will allow BPA to take advantage of any unknown thermal capacity. The present deterministic weather model is conservative overall and studies suggest a refined model will uncover additional unknown capacity. 14 refs., 40 figs., 7 tabs.
Date: August 31, 1990
Creator: Walker, Stel Nathan & Wade, John Edward
Object Type: Report
System: The UNT Digital Library
An automated flow calorimeter for heat capacity and enthalpy measurements at elevated temperatures and pressures (open access)

An automated flow calorimeter for heat capacity and enthalpy measurements at elevated temperatures and pressures

The need for highly accurate thermal property data for a broad range of new application fluids is well documented. To facilitate expansion of the current thermophysical database, an automated flow calorimeter was developed for the measurement of highly accurate isobaric heat capacities and enthalpies of fluids at elevated temperatures and pressures. The experimental technique utilizes traditional electrical power input, adiabatic flow calorimetry with a precision metering pump that eliminates the need for on-line flow rate monitoring. In addition, a complete automation system, greatly simplifies the operation of the apparatus and increases the rapidity of the measurement process. The range over which the instrument was tested, was 300--600 K and 0--12 Mpa, although the calorimeter should perform up to the original design goals of 700 K and 30 MPa. The new flow calorimeter was evaluated by measuring the mean, isobaric, specific heat capacities of liquid water and n-pentane. These experiments yielded an average deviation from the standard literature data of +0.02% and a total variation of 0.05%. Additional data analysis indicated that the overall measurement uncertainty was conservatively estimated as 0.2% with an anticipated precision of 0.1--0.15% at all operating conditions. 44 refs., 27 figs., 2 tabs.
Date: August 31, 1990
Creator: Yesavage, V. F.
Object Type: Report
System: The UNT Digital Library
Development of the coal quality expert: Project evaluation plan (open access)

Development of the coal quality expert: Project evaluation plan

The overall objective of this project is to provide the utility industry with a PC expert system to confidently and inexpensively evaluate the potential for coal cleaning, blending, and switching options to reduce emissions while producing lowest cost electricity. Specifically, this project will: (1) Enhance the existing Coal Quality Information System database and Coal Quality Impact Model to allow confident assessment of the effects of cleaning on specific power plant costs and performance. (2) Develop and validate a methodology, Coal Quality Expert, which allows accurate and detailed predictions of coal quality impacts on total power plant capital cost, operating cost, and performance based upon inputs from inexpensive bench-scale tests.
Date: August 31, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Development of the coal quality expert: Project evaluation plan. [Technical progress report, May--July 1990] (open access)

Development of the coal quality expert: Project evaluation plan. [Technical progress report, May--July 1990]

The overall objective of this project is to provide the utility industry with a PC expert system to confidently and inexpensively evaluate the potential for coal cleaning, blending, and switching options to reduce emissions while producing lowest cost electricity. Specifically, this project will: (1) Enhance the existing Coal Quality Information System database and Coal Quality Impact Model to allow confident assessment of the effects of cleaning on specific power plant costs and performance. (2) Develop and validate a methodology, Coal Quality Expert, which allows accurate and detailed predictions of coal quality impacts on total power plant capital cost, operating cost, and performance based upon inputs from inexpensive bench-scale tests.
Date: August 31, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Liquid Phase Methanol Laporte Process Development Unit: Modification, Operation, and Support Studies (open access)

Liquid Phase Methanol Laporte Process Development Unit: Modification, Operation, and Support Studies

A gas phase and a slurry phase radioactive tracer study was performed on the 12 ton/day Liquid Phase Methanol (LPMEOH) Process Development Unit (PDU) in LaPorte, Texas. To study the gas phase mixing characteristics, a radioactive argon tracer was injected into the feed gas and residence time distribution was generated by measuring the response at the reactor outlet. Radioactive manganese oxide powder was independently injected into the reactor to measure the slurry phase mixing characteristics. A tanks-in-series model and an axial dispersion model were applied to the data to characterize the mixing in the reactor. From the axial dispersion model, a translation to the number of CSTR's (continuous stirred tank reactors) was made for comparison purposes with the first analysis. Dispersion correlations currently available in the literature were also compared. The tanks-in-series analysis is a simpler model whose results are easily interpreted. However, it does have a few drawbacks; among them, the lack of a reliable method for scaleup of a reactor and no direct correlation between mixing in the slurry and gas phases. The dispersion model allows the mixing in the gas and slurry phases to be characterized separately while including the effects of phase transfer. This analysis offers …
Date: August 31, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
System 80+{trademark} standard design: CESSAR design certification. Volume 13: Amendment I (open access)

System 80+{trademark} standard design: CESSAR design certification. Volume 13: Amendment I

This report, entitled Combustion Engineering Standard Safety Analysis Report--Design Certification (CESSAR-DC), has been prepared in support of the industry effort to standardize nuclear plant designs. These documents describe the Combustion Engineering, Inc. System 80+{trademark} Standard Design. This report, Volume 13, documents increase and decrease of reactor cooling system inventory and radioactive material release from a subsystem or component.
Date: August 31, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library