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Large batch dimensional metrology demonstrated in the example of a LIGA fabricated spring.

Description: Deep x-ray lithography in combination with electroforming is capable of producing high precision metal parts in small lot series. This study deals with a high aspect ratio structure with overall dimensions on the order of 10 mm x 7 mm x 1.5 mm, with the smallest line width being 150 {micro}m. The lateral deviation from the design is to be kept to a minimum, preferably below 5 {micro}m. To ensure adequate quality control, a semi-automated metrology technique has been established to measure all parts. While the paper will give a brief overview of all involved techniques, it focuses on the method to measure the top and bottom of the parts and the top of geometries following the process. The instrument used is a View Engineering Voyager V6x12 microscope, which is fully programmable. The microscope allows direct measurement of geometries but also is capable of saving all captured data as point clouds. These point clouds play a central role when evaluating part geometry. After measuring the part, the point cloud is compared to the computer aided design (CAD) contour of the part, using a commercially available software package. The challenge of proper edge lighting on a nickel alloy part is evaluated by varying lighting conditions systematically. Results of two conditions are presented along with a set of optimized parameters. With the introduced set of tools, process flow can be monitored by measuring geometries, e.g. linewidths in every step of the process line. An example for such analysis is given. After delivery of a large batch of parts, extensive numbers of datasets were available allowing the evaluation of the variation of part geometries. Discussed in detail is the deviation from part top to part bottom geometries indicating swelling of the PMMA mold in the electroplating bath.
Date: April 1, 2004
Creator: Aigeldinger, Georg; Skala, Dawn M. & Ceremuga, Joseph T.
Partner: UNT Libraries Government Documents Department
open access

SMART SCREENING SYSTEM (S3) IN TACONITE PROCESSING

Description: The conventional vibrating machines used in processing plants have had undesirable high noise and vibration levels. They also have had unsatisfactorily low screening efficiency, high energy consumption, high maintenance cost, low productivity, and poor worker safety. These conventional vibrating machines have been used in most every processing plant. Most of the current material separation technology uses heavy and inefficient electric motors with an unbalance rotating mass to generate the shaking. In addition to being excessively noisy, inefficient, high-maintenance, these vibrating machines are often the bottleneck in the entire process. Furthermore, these motors along with the vibrating machines and supporting structure shake other machines and structure in the vicinity. The latter increases maintenance costs while reducing worker health and safety. The conventional vibrating fine screens at taconite processing plants have had the same problems as those listed above. This has resulted in lower screening efficiency, higher energy and maintenance cost, and lower productivity and workers safety concerns. The focus of this work is on the design of a high performance screening machine suitable for taconite processing plants. SmartScreens{trademark} technology uses miniaturized motors, based on smart materials, to generate the shaking. The underlying technologies are Energy Flow Control{trademark} and Vibration Control by Confinement{trademark}. These concepts are used to direct energy flow and confine energy efficiently and effectively to the screen function. The SmartScreens{trademark} technology addresses problems related to noise and vibration, screening efficiency, productivity, and maintenance cost and worker safety. Successful development of SmartScreens{trademark} technology will bring drastic changes to the screening and physical separation industry. The conceptual designs for key components of the SmartScreens{trademark} have been developed. These key components include: smart motors and resonators. It is shown that the smart motors have a good life and performance. The resonators are utilized to amplify motion generated by smart motors. Resonator designs …
Date: April 1, 2004
Creator: Allaei, Daryoush & Mohammed, Asim Syed
Partner: UNT Libraries Government Documents Department
open access

Precipitation-Front Modeling: Issues Relating to Nucleation and Metastable Precipitation in the Planned Nuclear Waste Repository at Yucca Mountain, Nevada

Description: The focus of the presentation is on certain aspects concerning the kinetics of heterogeneous reactions involving the dissolution and precipitation of unstable and metastable phases under conditions departing from thermodynamic equilibrium. These aspects are particularly relevant to transient thermal-hydrological-chemical (THC) processes that will occur as a result of the emplacement of radioactive waste within the Yucca Mountain Repository. Most important of these is a phenomenon commonly observed in altering soils, sediments and rocks, where less stable minerals precipitate in preference to those that are more stable, referred to as the Ostwald Rule of Stages, or the Ostwald Step Rule. W. Ostwald (1897) described the phenomenon characterizing his rule (as cited in Schmeltzer et al., 1998), thus: ''...in the course of transformation of an unstable (or metastable) state into a stable one the system does not go directly to the most stable conformation (corresponding to the modification with the lowest free energy) but prefers to reach intermediate stages (corresponding to other metastable modifications) having the closest free energy to the initial state''. This phenomenon is so widespread in natural geochemical systems, particularly under hydrothermal or low temperature conditions, that few geochemical parageneses involving the subcritical aqueous phase can be described without invoking the Ostwald Rule of Stages. Commonly observed systems where this phenomenon occurs include carbonates, silica, clay minerals, iron and manganese oxides, iron sulfides and zeolites (Morse and Casey, 1988). Simulations involving natural or anthropogenically modified reactive chemical transport must therefore be consistent with field observations describable by the Ostwald Rule. Geochemists have long been familiar with the Ostwald Rule, but, with one exception (Steefel and Van Cappellen, 1990), have not incorporated the underlying chemical principles justifying the Rule in reactive chemical transport simulations, other than through arbitrary fixes involving the suppression of the thermodynamically more stable phases, and by …
Date: April 1, 2004
Creator: Apps, J. A. & Sonnenthal, E. L.
Partner: UNT Libraries Government Documents Department
open access

Technetium-99 Behavior in Savannah River Site High Level Waste Sludges During Waste Processing

Description: This report presents results of an in-depth study of the behavior of technetium-99 (Tc-99) during waste processing operations at Savannah River Site. Tc-99 is a long lived (t1/2 equals 2.1E05 years) radioactive fission product of U-235. Its behavior during high level waste (HLW) processing is important to understand because Tc-99 can fractionate in the waste and appear in both the sludge and the salt tanks at Savannah River Site. Further it can also be soluble in groundwaters and thus is an important radionuclide that may dictate how much residual waste has to be removed from a waste tank to prepare it for permanent closure. Results are also presented for Pd-105, another important U-235 fission product. This fission product is stable, but it is important because it has a finite solubility in the sludge supernates in the HLW and is also used to calculate the concentration of the radionuclide Pd-107 that has to be reported in the Waste Acceptance Specifications to send HLW glass to a repository.
Date: April 1, 2004
Creator: BIBLER, NE
Partner: UNT Libraries Government Documents Department
open access

Fiber Optical Micro-Detectors for Oxygen Sensing in Power Plants Progress Report

Description: A reflection mode fiber optic oxygen sensor that can operate at high temperatures for power plant applications is being developed. The sensor is based on the {sup 3}O{sub 2} quenching of the red emission from hexanuclear molybdenum chloride clusters. The luminescence of Mo{sub 6}Cl{sub 12} immobilized in a sol-gel matrix was measured as a function of heater temperature up to 200 C, in an inert environment. While the luminescence decreased with temperature, the integrated intensity at 200 C should be sufficient to enable detection of the luminescence in a fiber geometry. Previously we found that aging Mo{sub 6}Cl{sub 12} at temperatures above 250 C converts the canary yellow Mo{sub 6}Cl{sub 12} to a non-luminescent gray solid. Optical and thermal aging experiments show that the alkali metal salts of Mo{sub 6}Cl{sub 12} have higher thermal stabilities and remain luminescent after aging at 280 C.
Date: April 1, 2004
Creator: Baker, Gregory L.; Ghosh, Ruby N. & III, D.J. Osborn
Partner: UNT Libraries Government Documents Department
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Cellulose and the Control of Growth Anisotropy

Description: The authors research aims to understand morphogenesis, focusing on growth anisotropy, a process that is crucial to make organs with specific and heritable shapes. For the award, the specific aims were to test hypotheses concerning how growth anisotropy is controlled by cell wall structure, particularly by the synthesis and alignment of cellulose microfibrils, the predominant mechanical element in the cell wall. This research has involved characterizing the basic physiology of anisotropic expansion, including measuring it at high resolution; and second, characterizing the relationship between growth anisotropy, and cellulose microfibrils. Important in this relationship and also to the control of anisotropic expansion are structures just inside the plasma membrane called cortical microtubules, and the research has also investigated their contribution to controlling anisotropy and microfibril alignment. In addition to primary experimental papers, I have also developed improved methods relating to these objectives as well as written relevant reviews. Major accomplishments in each area will now be described.
Date: April 1, 2004
Creator: Baskin, Tobias I.
Partner: UNT Libraries Government Documents Department
open access

Review of Current FFAG Lattice Studies in North America

Description: There has been a revival of interest in the use of fixed field alternating gradient accelerators (FFAGs) for many applications, including muon accelerators, high-intensity proton sources, and medical applications. The original FFAGs, and those recently built in Japan, have been based on a so-called scaling FFAG design, for which tunes are constant and the behavior in phase space is independent of energy with the exception of a scaling factor. Activity in the US and Canada has instead mostly focused on nonscaling designs, which, while having the large energy acceptance that characterizes an FFAG, do not obey the scaling relations of the scaling FFAG. Most of these designs have been based on magnets with a linear midplane field profile. A great deal of analysis, both theoretically and numerically, has occurred on these designs, and they are very well understood at this point. Some more recent work has occurred on designs with a nonlinear field profile. Since no non-scaling FFAG has ever been built, there is interest in building a small model which would accelerate electrons and demonstrate our understanding of non-scaling FFAG design.
Date: April 1, 2004
Creator: Berg, J. Scott; Plamer, Robert; Ruggiero, Alessandro; Trbojevic, Dejan; Keil, Eberhard; Johnstone, Carol et al.
Partner: UNT Libraries Government Documents Department
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Experimental investigation of burnup credit for safe transport, storage, and disposal of spent nuclear fuel.

Description: This report describes criticality benchmark experiments containing rhodium that were conducted as part of a Department of Energy Nuclear Energy Research Initiative project. Rhodium is an important fission product absorber. A capability to perform critical experiments with low-enriched uranium fuel was established as part of the project. Ten critical experiments, some containing rhodium and others without, were conducted. The experiments were performed in such a way that the effects of the rhodium could be accurately isolated. The use of the experimental results to test neutronics codes is demonstrated by example for two Monte Carlo codes. These comparisons indicate that the codes predict the behavior of the rhodium in the critical systems within the experimental uncertainties. The results from this project, coupled with the results of follow-on experiments that investigate other fission products, can be used to quantify and reduce the conservatism of spent nuclear fuel safety analyses while still providing the necessary level of safety.
Date: April 1, 2004
Creator: Berry, Donald T.; Harms, Gary A.; Ford, John T.; Walker, Sharon Ann; Helmick, Paul H. & Pickard, Paul S.
Partner: UNT Libraries Government Documents Department
open access

Corrective Action Decision Document for Corrective Action Unit 204: Storage Bunkers, Nevada Test Site, Nevada, Rev. No. 0

Description: The six bunkers included in CAU 204 were primarily used to monitor atmospheric testing or store munitions. The ''Corrective Action Investigation Plan (CAIP) for Corrective Action Unit 204: Storage Bunkers, Nevada Test Site, Nevada'' (NNSA/NV, 2002a) provides information relating to the history, planning, and scope of the investigation; therefore, it will not be repeated in this CADD. This CADD identifies potential corrective action alternatives and provides a rationale for the selection of a recommended corrective action alternative for each CAS within CAU 204. The evaluation of corrective action alternatives is based on process knowledge and the results of investigative activities conducted in accordance with the CAIP (NNSA/NV, 2002a) that was approved prior to the start of the Corrective Action Investigation (CAI). Record of Technical Change (ROTC) No. 1 to the CAIP (approval pending) documents changes to the preliminary action levels (PALs) agreed to by the Nevada Division of Environmental Protection (NDEP) and DOE, National Nuclear Security Administration Nevada Site Office (NNSA/NSO). This ROTC specifically discusses the radiological PALs and their application to the findings of the CAU 204 corrective action investigation. The scope of this CADD consists of the following: (1) Develop corrective action objectives; (2) Identify corrective action alternative screening criteria; (3) Develop corrective action alternatives; (4) Perform detailed and comparative evaluations of corrective action alternatives in relation to corrective action objectives and screening criteria; and (5) Recommend and justify a preferred corrective action alternative for each CAS within CAU 204.
Date: April 1, 2004
Creator: Boehlecke, Robert
Partner: UNT Libraries Government Documents Department
open access

Characterization of Turbiditic Oil Reservoirs Based on Geophysical Models of Their Formation

Description: A hierarchy of models and results are presented for the simulation of the dynamics and deposition of concentrated turbidity currents. The turbidity flows are assumed to be two-dimensional due to a constant flux release of dense suspensions spreading over a nonerodible flat surface. The three models presented are the Suspension Balance Model (SBM), the Simplified Suspension Balance Model (SSBM) and the Vertically Averaged Simplified Suspension Balance Model (VASSBM). The SBM is computationally intensive. However, simulations of the SBM indicate that the only a subset of the terms in the equations for the SBM are significant. The VASSBM is significantly faster computationally, and it is shown here to be an accurate approximation of the SBM model. For all the models, the two parameters that determine the dynamics and deposition of a concentrated turbidity current due to a constant flux release are the inlet volume fraction and the buoyancy number, a ratio of the buoyancy forces to viscous forces acting on the current. A parameter study is conducted for a volume fraction ranging from 10 to 40% and buoyancy numbers ranging from 0.01 to 0.2, typical of many real concentrated turbidity flows. It is found that the length or extent of deposit is mostly determined by inlet volume fraction and is relatively insensitive to the buoyancy number. The converse, though, is found for the thickness of the deposit.
Date: April 1, 2004
Creator: Bonnecaze, Roger T. & Lakshminarasimhan, Srivatsan
Partner: UNT Libraries Government Documents Department
open access

GridWise Standards Mapping Overview

Description: ''GridWise'' is a concept of how advanced communications, information and controls technology can transform the nation's energy system--across the spectrum of large scale, central generation to common consumer appliances and equipment--into a collaborative network, rich in the exchange of decision making information and an abundance of market-based opportunities (Widergren and Bosquet 2003) accompanying the electric transmission and distribution system fully into the information and telecommunication age. This report summarizes a broad review of standards efforts which are related to GridWise--those which could ultimately contribute significantly to advancements toward the GridWise vision, or those which represent today's current technological basis upon which this vision must build.
Date: April 1, 2004
Creator: Bosquet, Mia L.
Partner: UNT Libraries Government Documents Department
open access

Advanced Compressor Engine Controls to Enhance Operation, Reliability and Integrity

Description: This document provides a mid-term update for the ''Advanced Compressor Engine Controls to Enhance Operation, Reliability, and Integrity'' project. SwRI is conducting this project for DOE in conjunction with Cooper Energy Services, under DOE contract number DE-FC26-03NT41859. The objective of this one-year project is to develop, evaluate, and demonstrate advanced engine control technologies and hardware, specifically, closed-loop NO{sub x} emissions control on a two-stroke integral reciprocating engine/compressor used for pipeline gas transmission service. This work uses a Cooper-Bessemer GMVH-6 laboratory engine owned by Cooper Energy Services (CES) and installed in a test facility at Southwest Research Institute (SwRI). The gas transmission industry operates over 4,000 integral engine compressors, the majority being two-stroke, with a median age of 45 years and a median size of 2000 horsepower. These engines have historically exhibited poor performance and high emissions, due in part to poor engine control. The end results are misfires and partial burns that lead to increased fuel usage and exhaust emissions. Many of the slow-speed integral engines in the gas compression industry utilize control systems that are outdated, slow, and suffer from poor resolution. Research into more advanced control systems for integral compressor engines has increased tremendously in recent years. The recent advancements in control logic are being reviewed and analyzed in this program to understand the effectiveness of each. In addition, the application of a real-time NO{sub x} sensor feedback for closed-loop control is being investigated. To date, the strategies involving fuel/air equivalence ratio for a NO{sub x} prediction algorithm have been reviewed and analyzed. A hierarchy of control strategies will be outlined at the conclusion of this program. This hierarchy will range from the simplest and least expensive closed-loop control to an advanced system utilizing individual cylinder control. The ultimate control strategy is thought to be one that integrates …
Date: April 1, 2004
Creator: Bourn, Gary D.
Partner: UNT Libraries Government Documents Department
open access

Neutralization of Plutonium and Enriched Uranium Solutions Containing Gadolinium as a Neutron Poison

Description: Materials currently being dissolved in the HB-Line Facility will result in an accumulated solution containing an estimated uranium:plutonium (U:Pu) ratio of 4.3:1 and an 235U enrichment estimated at 30 per cent The U:Pu ratio and the enrichment are outside the evaluated concentration range for disposition to high level waste (HLW) using gadolinium (Gd) as a neutron poison. To confirm that the solution generated during the current HB-Line dissolving campaign can be poisoned with Gd, neutralized and discarded to the Savannah River Site (SRS) high level waste (HLW) system without undue nuclear safety concerns the caustic precipitation of surrogate solutions was examined. Experiments were performed with a U/Pu/Gd solution representative of the HB-Line estimated concentration ratio and also a U/Gd solution. Depleted U was used in the experiments as the enrichment of the U will not affect the chemical behavior during neutralization, but will affect the amount of Gd added to the solution. Settling behavior of the neutralized solutions was found to be comparable to previous studies. The neutralized solutions mixed easily and had expected densities of typical neutralized waste. The neutralized solids were found to be homogeneous and less than 20 microns in size. Partially neutralized solids were more amorphous than the fully neutralized solids. Based on the results of these experiments, Gd was found to be a viable poison for neutralizing a U/Pu/Gd solution with a U:Pu mass ratio of 4.3:1 thus extending the U:Pu mass ratio from the previously investigated 0-3:1 to 4.3:1. However, further work is needed to allow higher U concentrations or U:Pu ratios greater than investigated in this work.
Date: April 1, 2004
Creator: Bronikowski, M. G.
Partner: UNT Libraries Government Documents Department
open access

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. Photoacoustic measurements were collected using the off-line MEPA spectrometer with different microwave frequencies in order to develop photoacoustic microwave spectra of several fly ash samples. Microwaves from 500 MHz to 1800 MHz were used. Modifications to the on-line thermal elastic fly ash monitor include the improving the operation of the agitator for the bottom hopper, and installing a second diaphragm assembly in the freeboard section of the fly ash monitor. This second diaphragm assembly can be used with a second MEMS-based accelerometer and in conjunction with the primary accelerometer as a method of active noise control. Repeatability and linearity experiments have begun using the on-line fly ash monitor, with some results presented in this quarterly technical report.
Date: April 1, 2004
Creator: Brown, Robert C.; Weber, Robert J. & Sweterlitsch, Jeff
Partner: UNT Libraries Government Documents Department
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REALTIME MONITORING OF PIPELINES FOR THIRD-PARTY CONTACT

Description: Third-party contact with pipelines (typically caused by contact with a digging or drilling device) can result in mechanical damage to the pipe, in addition to coating damage that can initiate corrosion. Because this type of damage often goes unreported and can lead to eventual catastrophic failure of the pipe, a reliable, cost-effective method is needed for monitoring and reporting third-party contact events. The impressed alternating cycle current (IACC) pipeline monitoring method consists of impressing electrical signals on the pipe by generating a time-varying voltage between the pipe and the soil at periodic locations where pipeline access is available. The signal voltage between the pipe and ground is monitored continuously at receiving stations located some distance away. Third-party contact to the pipe that breaks through the coating changes the signal received at the receiving stations. In this project, the IACC monitoring method is being developed, tested, and demonstrated. Work performed to date includes a technology assessment, development of an IACC model to predict performance and assist with selection of signal operating parameters, and experimental measurements on a buried pipe at a test site. Initial results show that simulated contact can be detected. Future work will involve further refinement of the method and testing on operating pipelines.
Date: April 1, 2004
Creator: Burkhardt, Gary L.; Crouch, Alfred E. & Fisher, Jay L.
Partner: UNT Libraries Government Documents Department
open access

History and testimony of competency-based development at Sandia National Laboratories.

Description: More than ten years ago, Sandia managers defined a set of traits and characteristics that were needed for success at Sandia. Today, the Sandia National Laboratories Success Profile Competencies continue to be powerful tools for employee and leadership development. The purpose of this report is to revisit the historical events that led to the creation and adaptation of the competencies and to position them for integration in future employee selection, development, and succession planning processes. This report contains an account of how the competencies were developed, testimonies of how they are used within the organization, and a description of how they will be foundational elements of new processes.
Date: April 1, 2004
Creator: Burt, Rebecca A. & Narahara, Sheryl K.
Partner: UNT Libraries Government Documents Department
open access

Final Report for Crucible -Scale Radioactive Vitrification and Product Test of Waste Envelope B (AZ-102) Low-Activity Waste Glass

Description: A proof-of-technology demonstration for the Hanford River Protection Project (RPP) Waste treatment and Immobilization Plant (WTP) was performed by the Savannah River Technology Center (SRTC). As part of this demonstration, treated AZ-102 Low-Activity Waste supernate was vitrified using a crucible-scale furnace. Initial glass samples were quench-cooled and characterized for metals and radionuclides. The glass was also durability tested using the American Society for Testing and Materials (ASTM) Product Consistency Test (PCT) protocol. These tests used the AZ-102 glass formulation Low Activity Waste (LAW) B88 that targeted AZ-102 waste loading at 5 wt% Na2O. After these initial results were obtained with the quench-cooled LAWB88 glass, a prototypical container centerline cooling (CCC) program was supplied to SRTC by WTP. A portion of the quench-cooled LAWB88 glass was remelted and centerline cooled. Samples from the CCC low-activity AZ-102 glass waste form were durability tested using the PCT and characterized for crystalline phase identification.This final report documents the characterization and durability of this AZ-102 glass.
Date: April 1, 2004
Creator: CRAWFORD, CHARLES
Partner: UNT Libraries Government Documents Department
open access

Build up of electron cloud with different bunch pattern in the presence of solenoidal field

Description: We have augmented the code POSINST to include solenoid fields, and used it to simulate the build up of electron cloud due to electron multipacting in the PEP-II positron ring. We find that the distribution of electrons is strongly affected by the resonances associated with the cyclotron period and bunch spacing. In addition, we discover a threshold beyond which the electron density grows exponentially until it reaches the space charge limit. The threshold does not depend on the bunch spacing but does depend on the positron bunch population.
Date: April 1, 2004
Creator: Cai, Y.; Furman, M. A. & Pivi, M.
Partner: UNT Libraries Government Documents Department
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Drip shield Structural Response to Rock Fall

Description: The objective of this calculation is to determine areas over the drip shield (DS) top plate and side-walls where the residual stress values exceed 50% of Ti-7 yield strength. These areas will also be referred to as the damaged areas throughout this document. The scope of this document is limited to reporting the calculation results in terms of the damaged areas based on a chosen set of stress components. This calculation is intended for use in support of the preliminary design activities for the license application design of the DS. This calculation is associated with the DS design and was performed by the Waste Package and Components. AP-3.12Q, ''Design Calculations and Analyses'' is used to perform the calculation and develop the document. The DS is classified as a safety category item. Therefore, this calculation is subject to the Quality Assurance Requirements and Description. The information provided by the sketches attached to this calculation is that of the potential design of the type of DS considered in this calculation and provides the potential dimensions and materials for the DS design. The finite element (FE) calculation was performed by using the commercially available LS-DYNA Version (V)960 (Software Tracking Number [STN] 10300-960.1106-00, Ref. 7) FE code. The results of this calculation were evaluated using residual first principal stress. Subsequent analysis of areas determined by residual stresses have been reported in the results section of this document. The finite element mesh adequacy was determined based on the maximum stress intensity and maximum first principal stress. The current work processes and procedures for the control of the electronic management of data for this activity were conducted in accordance with AP-3.13Q, ''Design Control'' (Section 5.1.2).
Date: April 1, 2004
Creator: Ceylan, Z.
Partner: UNT Libraries Government Documents Department
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