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Comparison of a constraint directed search to a genetic algorithm in a scheduling application
Scheduling plutonium containers for blending is a time-intensive operation. Several constraints must be taken into account; including the number of containers in a dissolver run, the size of each dissolver run, and the size and target purity of the blended mixture formed from these runs. Two types of algorithms have been used to solve this problem: a constraint directed search and a genetic algorithm. This paper discusses the implementation of these two different approaches to the problem and the strengths and weaknesses of each algorithm.
Date:
April 1, 1993
Creator:
Abbott, L.
System:
The UNT Digital Library
Developing a Panelboard Trainer Using SIMVOX and PROVOX
Several challenges existed in creating a system that would be valuable for training operators: the robustness and accuracy of the process model, the operator interface to the process, and the communication between the operator interface and the process models. Cost and implementation time were also important factors. Two possible implementation plans were examined. The first option was to develop a computer tool through which the operator could operate the process through interaction with the mouse and keyboard. The entire panel board system could be created in computer graphics and a process model attached. The second option was to construct a complete replica of the control room panelboard in a training environment. Operations personnel expressed a strong preference for creating the panel board replica. Concerns were expressed about the comfort level of the operators training on a computer tool, and the value of the operators becoming thoroughly familiar with the physical location of the equipment in the panelboard was believed to be high. It was therefore decided to create a replica of the control room panelboard.
Date:
November 20, 1995
Creator:
Abbott, L. A.
System:
The UNT Digital Library
An automated vacuum gauge calibration system
An automated system for calibrating vacuum gauges over the pressure range of 10{sup {minus}6} to 0.1 Pa was designed and constructed at the National Institute of Standards and Technology (NIST) for the Department of Energy (DOE) Primary Standards Laboratory at Sandia National Laboratories (SNL). Calculable pressures are generated by passing a known flow of gas through an orifice of known conductance. The orifice conductance is derived from dimensional measurements and accurate flows are generated using metal capillary leaks. The expanded uncertainty (k = 2) in the generated pressure is estimated to be between 1% and 4% over the calibration range. The design, calibration results. and component uncertainties will be discussed.
Date:
April 1, 1998
Creator:
Abbott, P. J. & Benner, M. S.
System:
The UNT Digital Library
Gentleman Tom Abbott: Middleweight Champion of the Southwest
Article describes the life and career of middleweight boxing champion Tom Abbott, the grandfather of the author. Devon Abbott illustrates his impact not just in the ring, but in his careers as a football and track coach and a chief of police in McAlester, Oklahoma.
Date:
Spring 1990
Creator:
Abbott, Tom
System:
The Gateway to Oklahoma History
Flywheel energy storage using superconducting magnetic bearings
Storage of electrical energy on a utility scale is currently not practicable for most utilities, preventing the full utilization of existing base-load capacity. A potential solution to this problem is Flywheel Energy Storage (FES), made possible by technological developments in high-temperature superconducting materials. Commonwealth Research Corporation (CRC), the research arm of Commonwealth Edison Company, and Argonne National Laboratory are implementing a demonstration project to advance the state of the art in high temperature superconductor (HTS) bearing performance and the overall demonstration of efficient Flywheel Energy Storage. Currently, electricity must be used simultaneously with its generation as electrical energy storage is not available for most utilities. Existing storage methods either are dependent on special geography, are too expensive, or are too inefficient. Without energy storage, electric utilities, such as Commonwealth Edison Company, are forced to cycle base load power plants to meet load swings in hourly customer demand. Demand can change by as much as 30% over a 12-hour period and result in significant costs to utilities as power plant output is adjusted to meet these changes. HTS FES systems can reduce demand-based power plant cycling by storing unused nighttime capacity until it is needed to meet daytime demand.
Date:
April 1, 1994
Creator:
Abboud, R. G.; Uherka, K.; Hull, J. & Mulcahy, T.
System:
The UNT Digital Library
Multiphoton physics with x-rays: Two photon K-shell ionization of chlorine
A calculation of the two X-ray K-shell photoionization cross section of chlorine will be presented and the feasibility of an experiment will be discussed.
Date:
January 1, 1993
Creator:
Abdallah, J.; Collins, L. A.; Csanak, G.; Kyrala, G. A. & Schappert, G. T.
System:
The UNT Digital Library
Multiphoton physics with x-rays: Two photon K-shell ionization of chlorine
A calculation of the two X-ray K-shell photoionization cross section of chlorine will be presented and the feasibility of an experiment will be discussed.
Date:
April 1, 1993
Creator:
Abdallah, J.; Collins, L. A.; Csanak, G.; Kyrala, G. A. & Schappert, G. T.
System:
The UNT Digital Library
Reflux condensation of pure vapors with and without a noncondensable gas inside plain and enhanced tubes
Estimates of the surface-area and vapor-release reductions are obtained when commercially available enhanced tubes (spirally ribbed) replace plain tubes in a reflux unit condensing pure organic vapors with different concentrations of a noncondensable gas. This investigation was undertaken because there are no existing data and/or prediction methods that are applicable for these shell-and-tube condensers commonly used in the process industries. To obtain these estimates, existing design methods published in the open literature were used. The major findings are that (1) surface-area reductions can almost approach the single-phase heat transfer enhancement level, and (2) vapor-release reductions can approach a factor of four. The important implication is that enhanced tubes appear to be very cost effective for addressing the recovery of volatile organic vapors (VOCs), and for a vast number of different reflux-condenser applications.
Date:
June 1, 1997
Creator:
Abdelmessih, A. N.; Rabas, T. J. & Panchal, C. B.
System:
The UNT Digital Library
Using Cytochrome c{sub 3} to Make Selenium Nanowires
We report on a new method to make nanostructures, in this case selenium nanowires, in aqueous solution at room temperature. We used the protein cytochrome c{sub 3} to reduce selenate (SeO{sub 4}{sup 2{minus}}) to selenium (Se{sup 0}). Cytochrome c{sub 3} is known for its ability to catalyze reduction of metals including U{sup VI} {yields} U{sup IV}, Cr{sup VI} {yields} Cr{sup III}, Mo{sup VI} {yields} Mo{sup IV}, Cu{sup II} {yields} Cu{sup 0}, Pb{sup II} {yields} Pb{sup 0}, Hg{sup II} {yields} Hg{sup 0}. Nanoparticles of Se{sup 0} precipitated from an aqueous solution at room temperature, followed by spontaneous self-assembling into nanowires. Cytochrome c{sub 3} was extracted from the sulfate-reducing bacteria Desulfovibrio vulgaris (strain Holdenborough) and isolated by the procedure of DerVartanian and Legall.
Date:
November 24, 1999
Creator:
Abdelouas, A.; Franco, R.; Gong, W. L.; Lutze, W.; Moura, I. & Shelnutt, John A.
System:
The UNT Digital Library
Optimal choice of cupola furnace nominal operating point
One of the main goals in the operation of a cupola furnace is to keep the molten iron properties within prescribed bounds while maintaining the most economical operation for the cupola. In this paper the authors present a procedure to obtain the nominal values for the manipulated process variables. The nominal values are calculated by solving a constrained nonlinear programming optimization problem. Two different optimization problems are discussed and examples for using the procedure are presented.
Date:
August 1, 1998
Creator:
Abdelrahman, M.A. & Moore, K.L.
System:
The UNT Digital Library
Superconducting magnet design for Fixed-Field Alternating-Gradient (FFAG) accelerator
The FFAG accelerator requires static fields that increase with radius along the accelerator midplane according to B = B{sub 0} (R/R{sub 0}){sup 13.4}. The field is generated by equally spaced magnets around the circumference and varies from a maximum of 4.1 T to a minimum of {minus}1.9 T. The general coil design employs cryostable magnets wound with aluminum stabilized superconductor. Each magnet has resistive pole face windings outside of the cryostat to allow for field fine tuning after construction. A set of iron-free coil windings generate the required field distribution.
Date:
November 1, 1993
Creator:
Abdelsalam, M. & Kustom, R.
System:
The UNT Digital Library
Progress and Critical Issues for IFE Blanket and Chamber Research
Advances in high gain target designs for Inertial Fusion Energy (IFE), and the initiation of construction of large megajoule-class laser facilities in the U.S. (National Ignition Facility) and France (Laser-Megajoule) capable of testing the requirements for inertial fusion ignition and propagating burn, have improved the prospects for IFE. Accordingly, there have recently been modest increases in the US fusion research program related to the feasibility of IFE. These research areas include heavy-ion accelerators, Krypton-Fluoride (KrF) gas lasers, diode-pumped, solid-state (DPSSL) lasers, IFE target designs for higher gains, feasibility of low cost IFE target fabrication and accurate injection, and long-lasting IFE fusion chambers and final optics. Since several studies of conceptual IFE power plant and driver designs were completed in 1992-1996 [1-5], U.S. research in the IFE blanket, chamber, and target technology areas has focused on the critical issues relating to the feasibility of IFE concepts towards the goal of achieving economically-competitive and environmentally-attractive fusion energy. This paper discusses the critical issues in these areas, and the approaches taken to address these issues. The U.S. research in these areas, called IFE Chamber and Target Technologies, is coordinated through the Virtual Laboratory for Technology (VLT) formed by the Department of Energy in …
Date:
June 23, 1999
Creator:
Abdou, M.; Kulcinski, G. L.; Latkowski, J. F.; Logan, B. G.; Meier, W. R.; Moir, R. W. et al.
System:
The UNT Digital Library
Pattern of Thermal Fluctuations in a Recovery Boiler Floor
The floor of a black liquor recovey boiler at a mill in central Canada has experienced cracking and delamination of the composite tubing near the spout wall and deformation of the floor panels that is most severe in the vicinity of the spout wall. One possible explanation for the observed damage is impacts of salt cake falling from the convective section onto the floor. In order to determine if such impacts do occur, strain gauges and thermocouples were installed on the boiler floor in areas where cracking and deformation were most frequent. The data obtained from these instruments indicate that brief, sudden temperature fluctuations do occur, and changes in the strain experienced by the affected tube occur simultaneously. These fluctuations appear to occur less often along the spout wall and more frequently with increasing distance from the wall. The frequency of these temperature fluctuations is insufficient for thermal fatigue to be the sole cause of the cracking observed on the tubes, but the data are consistent with what might be expected from pieces of falling salt cake.
Date:
April 25, 1999
Creator:
Abdullah, Z.; Gorog, J. P.; Keiser, J. R.; Meyers, L. E. & Swindeman, R. W.
System:
The UNT Digital Library
A limit on {sigma} {center_dot} BR (B{sub c}{sup {+-}} {yields} J/{psi} + {pi}{sup {+-}})/{sigma} {center_dot} BR(B{sub u}{sup {+-}} {yields} J/{psi} + K{sup {+-}}) in {radical}s = 1.8 TeV proton-antiproton collisions
We report on the results of a search for the B{sub c} (b{bar c}) meson in the decay B{sub c}{sup +-} {yields} J/{psi} + {pi}{sup +-}. This search is guided by a control sample of decays of B{sub u} mesons to J/{psi} + K and uses {approx_equal} 75pb{sup -1} of data collected at the Collider Detector Facility (CDF) at Fermilab. The lifetime of the B{sub c} meson is unknown, so the 95% confidence level limit on {sigma} {center_dot} BR(B{sub c} {yields} {psi} + {pi})/{sigma} {center_dot} BR(B{sub u} {yields} {psi} + K) is obtained as a function of the B{sub c} lifetime.
Date:
July 15, 1995
Creator:
Abe, F.
System:
The UNT Digital Library
Measurement of the B{sup +} and B{sup 0} meson lifetimes using exclusive B {yields} {psi}K decays at CDF
The authors present recent CDF measurements of {tau}{sup +}, {tau}{sup 0}, and {tau}{sup +}/{tau}{sup 0} using exclusive B {yields} {psi}K decays, where B = B{sup +} or B{sup 0}, {psi} = J/{psi} or {psi}(2S), and K = K{sup +}, K*(892){sup 0}, K{sub S}{sup 0}, or K*(892){sup +}. The precision of these results is less than 10% and is nearly identical to that previously reported at LEP.
Date:
July 1995
Creator:
Abe, F.
System:
The UNT Digital Library
Measurement of the mass of the B{sub s}{sup 0} meson in {bar p}p collisions at {radical}s = 1.8 TeV
We measure the mass of the B{sub s}{sup 0} meson by fully reconstructing the decay B{sub s}{sup 0} {yields} J/{psi} {phi} with the subsequent decays J/{psi} {yields} {mu}{sup +} {mu}{sup {minus}} and {phi} {yields} K{sup +} K{sup {minus}}. The data was obtained from 19.3 pb{sup {minus}1} of integrated luminosity of {bar p}p collisions at {radical}s = 1.8 TeV using the Collider Detector at Fermilab (CDF). A sample of 80,000 inclusive J/{psi} {yields} {mu}{sup +}{mu}{sup {minus}} events is used to study systematic biases in track reconstruction and is used to calibrate the momentum scale. We reconstruct the kinematically similar decays B{sup {minus}} {yields} J/{psi} K{sup {minus}} and B{sup 0} {yields} J/{psi} K* to study the mass measurement technique used for the B{sup 0} meson. Based on the observation of 32 {plus_minus} 6 candidates, the mass of the B{sub s}{sup 0} meson is measured to be 5369.9 {plus_minus} 2.3 {plus_minus} 1.3 MeV/c{sup 2}.
Date:
July 1995
Creator:
Abe, F.
System:
The UNT Digital Library
Measurement of the polarization in the decays B{sup 0} {yields} J/{psi}K*{sup 0} and B{sub s}{sup 0} {yields} J/{psi}{phi}
The authors report on a measurement of the longitudinal polarization fraction in the decay B{sup 0} {yields} J/{psi}K*{sup 0} using data collected with the Collider Detector at Fermilab. B{sup 0} mesons are reconstructed through the decay chain B{sup 0} {yields} J/{psi} K*{sup 0}, J/{psi} {yields} {mu}{sup +}{mu}{sup {minus}}, K*{sup 0} {yields} K{sup +}{pi}{sup {minus}}. A sample of 65 {+-} 10 events is used to obtain the result {Lambda}{sub L}/{Lambda} = 0.65 {+-} 0.10 (stat) {+-} 0.04 (sys). The first measurement of {Lambda}{sub L}/{Lambda} in the decay B{sub s}{sup 0} {yields} J/{psi}{phi} is also presented.
Date:
July 1995
Creator:
Abe, F.
System:
The UNT Digital Library
Observation of B{sup +} {yields} J/{psi}{pi}{sup +}
We report on the observation of the Cabibbo-suppresed mode B{sup +} J/{psi}{pi}{sup +}, with J/{psi} {yields} {mu}{sup +}{mu}{sup {minus}}. Further, we calculate the relative branching ratio. BR(B{sup +} - J/{psi}{pi}{sup +})/BR(B{sup +} {yields} J/{psi}K{sup +}) and find a value of (4.9{sub {minus}1.7}{sup +}{plus_minus}1.1)%.
Date:
July 1, 1995
Creator:
Abe, F.
System:
The UNT Digital Library
Production of J/{Psi} from {chi}{sub c} decays at CDF
We have measured the fraction of J/{psi} originating from {chi}{sub c} states in p{bar p} collisions at {radical}s = 1.8 TeV in four bins of J/{psi} P{sub T}. The fraction in the inclusive CDF J/{psi} sample with P{sub T}{sup J/{psi}} > 4.0 GeV/c and {vert_bar}{eta}{sup J/{psi}}{vert_bar} < 0.6 is f{sub x}{sup J/{psi}} = 28.3{+-}1.6(stat){+-}6.8(syst)%. The fraction of J/{psi} from {chi}{sub c} not including contributions from B{yields}J/{psi}. X and B {yields} {chi}{sub c} X is f(Nob){chi}{sup J/{psi}} = 32.3{+-}2.0(stat){+-}8.5(syst)%. We have also found that directly produced {chi}{sub c}`s are produced in the ratio = {sigma}({chi}{sub c2}) over {sigma}({chi}{sub cl}) + {sigma}({chi}{sub c2})= 0.47{+-}0.08(stat){+-}0.02(syst.)
Date:
July 1, 1995
Creator:
Abe, F.
System:
The UNT Digital Library
Search for the decay B{sup 0} {yields} {mu}{sup +}{mu}{sup {minus}}
The authors present a search for the decays B{sub d}{sup 0} {yields} {mu}{sup +}{mu}{sup {minus}} and B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup {minus}} using 17.8 pb{sup {minus}1} of data collected with the Collider Detector at Fermilab (CDF) during 1992--1993 data taking period. They find no B{sub d}{sup 0} candidates in a mass window of [5.205, 5.355] GeV/c{sup 2} and 1 B{sub s}{sup 0} candidate in a mass window of [5.300, 5.450] GeV/c{sup 2}. Normalizing to the measured cross-section {sigma} (B{sup +}) = 2.39 {+-} 0.54 {micro}b for p{sub t}(B) > 6 GeV/c and {vert_bar}y(B){vert_bar} < 1 and assuming {sigma}(B{sup +}) = {sigma}(B{sub d}{sup 0}) = 3{sigma}(B{sub s}{sup 0}), they find Br(B{sub d}{sup 0} {yields} {mu}{sup +}{mu}{sup {minus}}) < 1.6 {times} 10{sup {minus}6} and Br(B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup {minus}}) < 8.4 {times} 10{sup {minus}6} at 90% confidence level. These limits are significant improvements of previous measurements.
Date:
July 1, 1995
Creator:
Abe, F.
System:
The UNT Digital Library
Measurement of the B+ and B0 Lifetimes With Topological Vertexing at SLD
The lifetimes of the B{sup +} (B{sub u}) and B{sup 0} (B{sub d}) mesons have been measured using a sample of 150,000 hadronic Z{sup 0} decays collected by the SLD experiment at the SLC between 1993 and 1995. The analysis reconstructs the decay length and charge of the B meson using a novel topological technique. This method results in a high statistics sample of 6,033 (3,665) charged (neutral) vertices. The ratio of B{sup +}:B{sup 0} decays in the charged (neutral) sample is 1.8:1 (1:2.3).
Date:
July 1, 1996
Creator:
Abe, K.; Abe, K. & Abt, I.
System:
The UNT Digital Library
Measurement of the Z{sup 0}-Lepton Coupling Asymmetries A{sub l}
The authors present direct measurements of the Z{sup 0}-lepton coupling asymmetries, A{sub e}, A{sub {mu}}, and A{sub {tau}}. It is based on a data sample selected from 170 k Z{sup 0} decays collected by the SLD detector. The Z`s are produced by collisions of polarized e{sup {minus}} with unpolarized e{sup +} bunches at SLC. The couplings are extracted from the measurement of the left-right forward-backward asymmetry for each lepton species. The preliminary results (using information from all leptonic data for A{sub e}) are: A{sub e} = 0.148 {+-} 0.016, A{sub {mu}} = 0.102 {+-} 0.033 and A{sub {tau}} = 0.190 {+-} 0.034.
Date:
July 22, 1996
Creator:
Abe, K.; Abe, K. & Abt, I.
System:
The UNT Digital Library
Symmetry Tests in Polarized Z{Sup 0} Decays to b{anti b}g
Angular asymmetries have been measured in polarized Z{sup 0} decays to b{anti b}g collected by the SLD experiment at the SLC. A high purity b{anti b}g event sample is selected utilizing lifetime information given by the SLD CCD pixel vertex detector and the stable micron-size SLC beams, and the b- and {anti b}-jets are identified using lifetime information and momentum-weighted track charge. The forward-backward asymmetry is observed in the b-jet polar angle distribution, and the parity-violation parameter is measured to test the Standard Model. Two angular correlations between the three-jet plane and the Z{sup 0} polarization are studied. The CP-even and T-odd angular asymmetry, and the CP-odd and T-odd angular asymmetry are sensitive to physics beyond the Standard Model. The authors measure the expectation values of these quantities to be consistent with zero and set limits on the correlations.
Date:
June 1, 1997
Creator:
Abe, K.; Abe, K. & Akagi, T.
System:
The UNT Digital Library
A Preliminary Improved Test of the Flavor Independence of Strong Interactions
The authors present an improved comparison of the strong couplings of gluons to light (u, d, and s), c, and b quarks, determined from multijet rates in flavor-tagged samples of hadronic Z{sup 0} decays recorded with the SLC Large Detector at the SLAC Linear Collider between 1993 and 1995. Flavor separation on the basis of lifetime and decay multiplicity differences among hadrons containing light, c, and b quarks was made using the SLD precision tracking system, yielding tags with high purity and low bias against {ge} 3-jet final states. They find: {alpha}{sub s}{sup uds}/{alpha}{sub s}{sup all} = 0.997 {+-} 0.011(stat) {+-} 0.011(syst) {+-} 0.005(theory), {alpha}{sub s}{sup c}/{alpha}{sub s}{sup all} = 0.984 {+-} 0.042 {+-} 0.053 {+-} 0.022, {alpha}{sub s}{sup b}/{alpha}{sub s}{sup all} = 1.022 {+-} 0.019 {+-} 0.023 {+-} 0.012.
Date:
June 1, 1997
Creator:
Abe, K.; Abe, K.; Akagi, T. & Collaboration, SLD
System:
The UNT Digital Library