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Supporting multiple control systems at Fermilab

Description: The Fermilab control system, ACNET, is used for controlling the Tevatron and all of its pre-accelerators. However, other smaller experiments at Fermilab have been using different controls systems, in particular DOOCS and EPICS. This paper reports some of the steps taken at Fermilab to integrate support for these outside systems. We will describe specific tools that we have built or adapted to facilitate interaction between the architectures. We also examine some of the difficulties that arise from managing this heterogeneous environment. Incompatibilities as well as common elements will be described.
Date: October 1, 2009
Creator: Nicklaus, Dennis J.
Partner: UNT Libraries Government Documents Department

Selection of oil coolers to avoid congealing

Description: Report presenting a study of oil coolers, especially in regards to three factors: the congealing tendency of the cooler, the power cost chargeable to the installation, and the performance characteristics of the oil cooler in operation at altitude.
Date: July 1943
Creator: Martin, Dennis J.
Partner: UNT Libraries Government Documents Department

Summary of flutter experiences as a guide to the preliminary design of lifting surfaces on missiles

Description: Presented is a limited review of some experiences in flight testing of missiles and of wing flutter investigations that may be of interest in missile design. Several types of flutter of concern in missile studies are briefly described. Crude criteria are presented for two of the most common types of flutter to permit a rapid estimate to be made of the probability of the occurrence of flutter. Many of the details of the flutter problem have been omitted, and only the broader elements have been retained so as to give the designer an overall view of the subject.
Date: February 1958
Creator: Martin, Dennis J.
Partner: UNT Libraries Government Documents Department

Final Report: BaBar Detector and Experimental at SLAC, September 30, 1998 - September 29, 1999

Description: The Prairie View A&M University High Energy Physics Group with its contingent of three undergraduates physics majors, joined the BaBar Collaboration at SLAC in September 1994. BaBar is the experiment and detector running in the PEP-II ring at SLAC as part of the Asymmetric B Factory project there to study CP violation and heavy flavor physics. The focus of our effort before this year was with the Muon/Neutral Hadron Detector/Instrumented Flux Return (IFD) subgroup within the BaBar collaboration, and particularly with the GEANT simulation of the IFR. With the GEANT3 simulation essentially frozen, and the GEANT4 full simulation of the IFR done, we have decided to redirect our efforts toward other areas.
Date: January 20, 2000
Creator: Judd, Dennis J.
Partner: UNT Libraries Government Documents Department

EDI as a Treatment Module in Recycling Spent Rinse Waters

Description: Recycling of the spent rinse water discharged from the wet benches commonly used in semiconductor processing is one tactic for responding to the targets for water usage published in the 1997 National Technology Roadmap for Semiconductors (NTRS). Not only does the NTRS list a target that dramatically reduces total water usage/unit area of silicon manufactured by the industry in the future but for the years 2003 and beyond, the NTRS actually touts goals which would have semiconductor manufacturers drawing less water from a regional water supply per unit area of silicon manufactured than the quantity of ultrapure water (UPW) used in the production of that same silicon. Achieving this latter NTRS target strongly implies more widespread recycling of spent rinse waters at semiconductor manufacturing sites. In spite of the fact that, by most metrics, spent rinse waters are of much higher purity than incoming municipal waters, recycling of these spent rinse waters back into the UPW production plant is not a simple, straightforward task. The rub is that certain of the chemicals used in semiconductor manufacturing, and thus potentially present in trace concentrations (or more) in spent rinse waters, are not found in municipal water supplies and are not necessarily removed by the conventional UPW production sequence used by semiconductor manufacturers. Some of these contaminants, unique to spent rinse waters, may actually foul the resins and membranes of the UPW system, posing a threat to UPW production and potentially even causing a shutdown.
Date: August 11, 1999
Creator: Donovan, Robert P. & Morrison, Dennis J.
Partner: UNT Libraries Government Documents Department

Research on trust-region algorithms for nonlinear programming

Description: This report discusses research on the following topics: interior- point methods for linear programming; trust-region SQP newton's method for general nonlinear programming problems; trust-region SQP newton's method for large sparse nonlinear programming problems with applications to oil reservoir management; a unified approach to global convergence of trust-region methods for nonsmooth optimization; and SQP augmented lagrangian BRGS algorithm for constrained optimization. (LSP).
Date: November 1, 1991
Creator: Dennis, J.E. & Tapia, R.A.
Partner: UNT Libraries Government Documents Department

Recent experimental flutter studies

Description: Report presenting some highlights of recent experimental studies of flutter at high speeds. Flutter problems have become more varied with the advent of transonic flight and importance of aeroelasticity, and the flutter field has merged with other aspect of aeroelasticity such as divergence and buffeting. The two main subjects of flutter, classical flutter and stall flutter, are explored in these studies.
Date: June 12, 1951
Creator: Regier, Arthur A. & Martin, Dennis J.
Partner: UNT Libraries Government Documents Department

Tank 241-AY-102 Secondary Liner Corrosion Evaluation - 14191

Description: In October 2012, Washington River Protection Solutions, LLC (WRPS) determined that the primary tank of 241-AY-102 (AY-102) was leaking. A number of evaluations were performed after discovery of the leak which identified corrosion from storage of waste at the high waste temperatures as one of the major contributing factors in the failure of the tank. The propensity for corrosion of the waste on the annulus floor will be investigated to determine if it is corrosive and must be promptly removed or if it is benign and may remain in the annulus. The chemical composition of waste, the temperature and the character of the steel are important factors in assessing the propensity for corrosion. Unfortunately, the temperatures of the wastes in contact with the secondary steel liner are not known; they are estimated to range from 45 deg C to 60 deg C. It is also notable that most corrosion tests have been carried out with un-welded, stress-relieved steels, but the secondary liner in tank AY-102 was not stress-relieved. In addition, the cold weather fabrication and welding led to many problems, which required repeated softening of the metal to flatten secondary bottom during its construction. This flame treatment may have altered the microstructure of the steel.
Date: January 7, 2014
Creator: Boomer, Kayle D.; Washenfelder, Dennis J. & Johnson, Jeremy M.
Partner: UNT Libraries Government Documents Department

Overview of Hanford Single Shell Tank (SST) Structural Integrity - 14023

Description: To improve the understanding of the single-shell tanks (SSTs) integrity, Washington River Protection Solutions, LLC (WRPS), the USDOE Hanford Site tank contractor, developed an enhanced Single-Shell Tank Integrity Project (SSTIP) in 2009. An expert panel on SST integrity, consisting of various subject matters experts in industry and academia, was created to provide recommendations supporting the development of the project. This panel developed 33 recommendations in four main areas of interest: structural integrity, liner degradation, leak integrity and prevention, and mitigation of contamination migration, Seventeen of these recommendations were used to develop the basis for the M-45-10-1 Change Package for the Hanford Federal Agreement and Compliance Order, which is also known as the Tri-Party Agreement. The structural integrity of the tanks is a key element in completing the cleanup mission at the Hanford Site. There are eight primary recommendations related to the structural integrity of Hanford Single-Shell Tanks. Six recommendations are being implemented through current and planned activities. The structural integrity of the Hanford is being evaluated through analysis, monitoring, inspection, materials testing, and construction document review. Structural evaluation in the form of analysis is performed using modern finite element models generated in ANSYS. The analyses consider in-situ, thermal, operating loads and natural phenomena such as earthquakes. Structural analysis of 108 of 149 Hanford Single-Shell Tanks has concluded that the tanks are structurally sound and meet current industry standards. Analysis of the remaining Hanford Single-Shell Tanks is scheduled for FY2014. Hanford Single-Shell Tanks are monitored through a dome deflection program. The program looks for deflections of the tank dome greater than � inch. No such deflections have been recorded. The tanks are also subjected to visual inspection. Digital cameras record the interior surface of the concrete tanks, looking for cracks and other surface conditions that may indicate signs of structural distress. ...
Date: November 14, 2013
Creator: Rast, Richard S.; Washenfelder, Dennis J. & Johnson, Jeremy M.
Partner: UNT Libraries Government Documents Department

On improving linear solver performance: a block variant of GMRES

Description: The increasing gap between processor performance and memory access time warrants the re-examination of data movement in iterative linear solver algorithms. For this reason, we explore and establish the feasibility of modifying a standard iterative linear solver algorithm in a manner that reduces the movement of data through memory. In particular, we present an alternative to the restarted GMRES algorithm for solving a single right-hand side linear system Ax = b based on solving the block linear system AX = B. Algorithm performance, i.e. time to solution, is improved by using the matrix A in operations on groups of vectors. Experimental results demonstrate the importance of implementation choices on data movement as well as the effectiveness of the new method on a variety of problems from different application areas.
Date: May 10, 2004
Creator: Baker, A H; Dennis, J M & Jessup, E R
Partner: UNT Libraries Government Documents Department

Distribution and Trend of Nitrate, Chloride, and Total Solids in Water in the Magothy Aquifer in Southeast Nassau County, New York, from the 1950's Through 1973

Description: Abstract: Concentrations of nitrate, chloride, and total sol ids in water in the Magothy aquifer, southeast Nassau County, N.Y., show a steadily increasing trend from the early 1950's to 1973. Vertical distribution of nitrate, chloride, and total-solids concentrations as shown in sections of the study area indicate downward movement of these constituents. Maximum concentrations are in a zone underlying the areas of Westbury, Hicksvil.le, and Plainview. Nitrate (as nitrogen) concentration increased from 4-5 milligrams per liter to 7 milligrams per liter in the area of Westbury and from 3 to 10 milligrams per liter in Plainview during the period 1950-73. During this same period, a 10 milligram-per-liter line of equal-chloride concentration on a cross section in the Westbury area moved downward a distance of less than 50 feet (15 meters), and in the area of Hicksville nearly 150 feet (45 meters). Total-solids concentration doubled in the area of Plainview, where maximum downward movement of pollutants was observed.
Date: August 1976
Creator: Ku, Henry F. H. & Sulam, Dennis J.
Partner: UNT Libraries Government Documents Department

Research on trust-region algorithms for nonlinear programming. Final technical report, 1 January 1990--31 December 1992

Description: Goal of the research was to develop and test effective, robust algorithms for general nonlinear programming (NLP) problems, particularly large or otherwise expensive NLP problems. We discuss the research conducted over the 3-year period Jan. 1990-Dec. 1992. We also describe current and future directions of our research.
Date: December 19, 1995
Creator: Dennis, J. E., Jr. & Tapia, R. A.
Partner: UNT Libraries Government Documents Department

A Structural Approach to Four Theories of Group Development

Description: The goal of this study was to attempt to develop a classification scheme that systematically related individual behavior, interpersonal behavior, and group interactions for the purpose of using the resulting classification scheme to evaluate theories of group development proposed by Bion, Bennis and Shepard, Bales, and Tuckman and Jensen. It was assumed that theorists' presuppositions about the structure of groups might influence their theories. Using a qualitative process of analysis, a structural classification scheme (SCS) was developed based upon transformative and generative rules, utilizing the General System Theory subsystem process of self-regulated boundary operations. The SCS protocol was employed to categorize and compare the theories of group development proposed by Bion, Bennis and Shepard, Bales, and Tuckman and Jensen. The resulting categorization of theories indicated that relationships existed among and between a group's structural properties, the complexity and type of communication connections among and between group members, and the size of the group. In addition, a common structural relationship was demonstrated to exist among and between individual, dyadic, and triadic group forms. A similar structural relationship was also speculated to exist between groups of any size. It was concluded that a structural approach to groups may offer insight to group leaders and members in recognizing and creating alternative frameworks that best fit a group's structure to its task. This approach may have broad implications in that it suggests that group goals might best be considered before the structure of the group is determined. In addition, a structural approach was also speculated to be an emotionally neutral alternative method of discussing individual and group behavior.
Date: May 1997
Creator: King, Dennis J., 1945-
Partner: UNT Libraries

Identification Manual for Dietary Vegetation of the Hawaiian Green Turtle Chelonia mydas

Description: From introduction: This manual is designed to assist sea turtle biologists and other non-physologists in the identification of the food items contained in the gastrointestinal tract of green turtles (Chelonia mydas) sampled from the Hawaiian Islands. The manual contains many of the most common algal species found in crop/stomach samples taken from Hawaiian green turtles.
Date: June 2000
Creator: Russell, Dennis J. & Balazs, George H.
Partner: UNT Libraries Government Documents Department

Evaluation of Hanford Single-Shell Waste Tanks Suspected of Water Intrusion - 14196

Description: Intrusions evaluations for twelve single-shell tanks were completed in 2013. The evaluations consisted of remote visual inspections, data analysis, and calculations of estimated intrusion rates. The observation of an intrusion or the preponderance of evidence confirmed that six of the twelve tanks evaluated had intrusions. These tanks were tanks 241-A-103, BX-101, BX-103, BX-110, BY-102, and SX-106.
Date: November 14, 2013
Creator: Feero, Amie J.; Washenfelder, Dennis J.; Johnson, Jeremy M. & Schofield, John S.
Partner: UNT Libraries Government Documents Department

Double-Shell Tank Visual Inspection Changes REsulting from the Tank 241-AY-102 Primary Tank Leak - 14193

Description: As part of the Double-Shell Tank (DST) Integrity Program, remote visual inspections are utilized to perform qualitative in-service inspections of the DSTs in order to provide a general overview of the condition of the tanks. During routine visual inspections of tank 241-AY -1 02 (A Y -1 02) in August 2012, anomalies were identified on the annulus floor which resulted in further evaluations. In October 2012, Washington River Protection Solutions, LLC determined that the primary tank of AY -102 was leaking. Following identification of the tank AY-102 probable leak cause, evaluations considered the adequacy of the existing annulus inspection frequency with respect to the circumstances of the tank AY-1021eak and the advancing age of the DST structures. The evaluations concluded that the interval between annulus inspections should be shortened for all DSTs, and each annulus inspection should cover > 95 percent of annulus floor area, and the portion of the primary tank (i.e., dome, sidewall, lower knuckle, and insulating refractory) that is visible from the annulus inspection risers. In March 2013, enhanced visual inspections were performed for the six oldest tanks: 241-AY-101, 241-AZ-101,241-AZ-102, 241-SY-101, 241-SY-102, and 241-SY-103, and no evidence of leakage from the primary tank were observed. Prior to October 2012, the approach for conducting visual examinations of DSTs was to perform a video examination of each tank's interior and annulus regions approximately every five years (not to exceed seven years between inspections). Also, the annulus inspection only covered about 42 percent of the annulus floor.
Date: November 14, 2013
Creator: Girardot, Crystal L.; Washenfelder, Dennis J.; Johnson, Jeremy M. & Engeman, Jason K.
Partner: UNT Libraries Government Documents Department

Potential for Accelerated Bioremediation and Restoration of Oil-Impacted Marshes through the Selection of Superior Oil-Tolerant Vegetation

Description: Report describing a study of the genotypes two plants (Spartina Patens and Spartina Alterniflora) that are tolerant to oil spills that have occurred in the coastal marshes of Louisiana. The research was to determine if these two plants could utilized for restoration and bioremediation of areas effected by oil spills. A plants tolerance to oil is determined by three factors: growth response and plant production, superior vegetative regrowth in soil effected by oil, and superior oil degradation potential.
Date: May 2000
Creator: Hester, Mark W.; Lin, Quixan; Mendellsohn, Irving A. & DesRoches, Dennis, J.
Partner: UNT Libraries Government Documents Department

Restored Drill Cuttings for Wetlands Creation: Results of Mesocosm Approach to Emulate Field Conditions Under Varying Salinity and Hydrologic Conditions

Description: This study builds upon earlier research conducted by Southeastern Louisiana University concerning the efficacy of utilizing processed drill cuttings as an alternative substrate source for wetland rehabilitation (wetland creation and restoration). Previous research has indicated that processed drill cuttings exhibit a low degree of contaminant migration from the process drill cuttings to interstitial water and low toxicity, as tested by seven-day mysid shrimp chronic toxicity trials.
Date: February 21, 2001
Creator: Hester, Mark W.; Shaffer, Gary P.; M., Willis Jonathan & DesRoches, Dennis J.
Partner: UNT Libraries Government Documents Department

Rapid, automated gas chromatographic detection of organic compounds in ultra-pure water

Description: An automated gas chromatography was used to analyze water samples contaminated with trace (parts-per-billion) concentrations of organic analytes. A custom interface introduced the liquid sample to the chromatography. This was followed by rapid chromatographic analysis. Characteristics of the analysis include response times less than one minute and automated data processing. Analytes were chosen based on their known presence in the recycle water streams of semiconductor manufacturers and their potential to reduce process yield. These include acetone, isopropanol, butyl acetate, ethyl benzene, p-xylene, methyl ethyl ketone and 2-ethoxy ethyl acetate. Detection limits below 20 ppb were demonstrated for all analytes and quantitative analysis with limited speciation was shown for multianalyte mixtures. Results are discussed with respect to the potential for on-line liquid process monitoring by this method.
Date: February 15, 2000
Partner: UNT Libraries Government Documents Department