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A Lift-Cancellation Technique in Linearized Supersonic-Wing Theory

Description: "A lift-cancellation technique is presented for determining load distributions on thin wings at supersonic speeds. The loading on a wing having a prescribed plan form is expressed as the loading of a known related wing (such as a two-dimensional or triangular wing) minus the loading of an appropriate cancellation wing. The lift-cancellation technique can be used to find the loading on a large variety of wings. Applications to swept wings having curvilinear plan forms and to wings having reentrant side edges are indicated" (p. 65).
Date: January 16, 1950
Creator: Mirels, Harold
Partner: UNT Libraries Government Documents Department

ANOMALY STRUCTURE OF SUPERGRAVITY AND ANOMALY CANCELLATION

Description: We display the full anomaly structure of supergravity, including new D-term contributions to the conformal anomaly. This expression has the super-Weyl and chiral U(1){sub K} transformation properties that are required for implementation of the Green-Schwarz mechanism for anomaly cancellation. We outline the procedure for full anomaly cancellation. Our results have implications for effective supergravity theories from the weakly coupled heterotic string theory.
Date: June 10, 2009
Creator: Butter, Daniel & Gaillard, Mary K.
Partner: UNT Libraries Government Documents Department

Lift-Cancellation Technique in Linearized Supersonic-Wing Theory

Description: Note presenting a lift-cancellation technique for determining load distributions on thin wings at supersonic speeds. A general expression is derived for the load distribution over a cancellation wing. The lift cancellation technique is illustrated for swept wings with curvilinear plan forms.
Date: August 1950
Creator: Mirels, Harold
Partner: UNT Libraries Government Documents Department

Enhanced Processing for a Towed Array Using an Optimal Noise Canceling Approach

Description: Noise self-generated by a surface ship towing an array in search of a weak target presents a major problem for the signal processing especially if broadband techniques are being employed. In this paper we discuss the development and application of an adaptive noise canceling processor capable of extracting the weak far-field acoustic target in a noisy ocean acoustic environment. The fundamental idea for this processor is to use a model-based approach incorporating both target and ship noise. Here we briefly describe the underlying theory and then demonstrate through simulation how effective the canceller and target enhancer perform. The adaptivity of the processor not only enables the ''tracking'' of the canceller coefficients, but also the estimation of target parameters for localization. This approach which is termed ''joint'' cancellation and enhancement produces the optimal estimate of both in a minimum (error) variance sense.
Date: July 21, 2005
Creator: Sullivan, E J & Candy, J V
Partner: UNT Libraries Government Documents Department

Speech Articulator and User Gesture Measurements Using Micropower, Interferometric EM-Sensore

Description: Very low power, GHz frequency, ''radar-like'' sensors can measure a variety of motions produced by a human user of machine interface devices. These data can be obtained ''at a distance'' and can measure ''hidden'' structures. Measurements range from acoustic induced 10-micron amplitude vibrations of vocal tract tissues, to few centimeter human speech articulator motions, to meter-class motions of the head, hands, or entire body. These EM sensors measure ''fringe motions' as reflected EM waves are mixed with a local (homodyne) reference wave. These data, when processed using models of the system being measured, provide real time states of interface positions vs. time. An example is speech articulator positions vs. time in the user's body. This information appears to be useful for a surprisingly wide range of applications ranging from speech coding and recognition, speaker or object identification, noise cancellation, hand or head motions for cursor direction, and other applications.
Date: September 15, 2000
Creator: Holzrichter, J.F.
Partner: UNT Libraries Government Documents Department

Two Methods for a First Order Hardware Gradiometer Using Two HTS SQUID's

Description: Two different systems for noise cancellation (first order gradiometers) have been developed using two similar high temperature superconducting (HTS) SQUIDs. ''Analog'' gradiometry is accomplished in hardware by either (1) subtracting the signals from the sensor and background SQUIDs at a summing amplifier (parallel technique) or (2) converting the inverted background SQUID signal to a magnetic field at the sensor SQUID (series technique). Balance levels achieved are 2000 and 1000 at 20 Hz for the parallel and series methods respectively. The balance level as a function of frequency is also presented. The effect which time delays in the two sets of SQUID electronics have on this balance level is presented and discussed.
Date: September 15, 1998
Creator: Espy, M.A.; Flynn, E.R.; Kraus, R.H., Jr. & Matlachov, A.
Partner: UNT Libraries Government Documents Department

CANCELLATION OF PRINT JOURNALS AT A NATIONAL RESEARCH LABORATORY

Description: By de-emphasizing the print journal collection our organization has been able to accomplish several goals: provide access to additional digital resources through cost savings; support customers' requirements for information at the desktop; reduce staff costs; free staff time for higher level tasks; and reduce space costs. Print journal cancellations have now become incorporated into the regular routine of our library. We have a proven process in place that we can rely on to provide sound decisions. We have been aided in our successful accomplishments by the enormous support of our customers, our Library Advisory Board and laboratory management. Opportunities and challenges will continue to present themselves as our organization continues to emphasize digital resources over print.
Date: April 1, 2001
Creator: HOOVER, C. L.
Partner: UNT Libraries Government Documents Department

Compensation of dogleg effect in Fermilab Booster

Description: The edge focusing of dogleg magnets in Fermilab Booster has been causing severe distortion to the horizontal linear optics. The doglegs are vertical rectangular bends, therefore the vertical edge focusing is canceled by body focusing and the overall effect is focusing in the horizontal plane. The maximum horizontal beta function is changed from 33.7m to 46.9m and maximum dispersion from 3.19m to 6.14m. Beam size increases accordingly. This is believed to be one of the major reasons of beam loss. In this technote we demonstrate that this effect can be effectively corrected with Booster's quadrupole correctors in short straight sections (QS). There are 24 QS correctors which can alter horizontal linear optics with negligible perturbation to the vertical plane. The currents of correctors are determined by harmonic compensation, i.e., cancellation of dogleg's harmonics that are responsible for the distortion with that of QS correctors. By considering a few leading harmonics, the ideal lattice can be partly restored. For the current dogleg layout, maximum {beta}{sub x} is reduced to 40.6m and maximum D{sub x} is reduced to 4.19m. This scheme can be useful after the dogleg in section No.3 is repositioned. In this case it can bring {beta}{sub x} from 40.9m down to 37.7m, D{sub x} from 4.57m to 4.01m.
Date: October 6, 2003
Creator: Huang, Xiaobiao & Ohnuma, Sho
Partner: UNT Libraries Government Documents Department

Hadronic loops and the OZI rule

Description: Arguments based on unitarity indicate that hadronic loop diagrams should produce large violations of the OZI (Okubo-Zweig-Iizuka) rule. The mechanism by which these corrections are evaded has long been a mystery. We have found that there is an exact cancellation of all such loops in a particular (quark model) limit and that, at least for the rho-->omega system which we have studied in detail, the cancellation is maintained in a realistic calculation which takes into account departures from this limit.
Date: August 1, 1991
Creator: Isgur, Nathan
Partner: UNT Libraries Government Documents Department

COMPARISON OF DOUBLE BEND AND TRIPLE BEND ACHROMATIC LATTICE STRUCTURES AND NSLS-II.

Description: The Double Bend Achromatic (DBA) and the Triple Bend Achromatic (TBA) lattice have been studied rather extensively for use for the NSLS-II storage ring. The advantage of the TBA compared to the DBA in terms of emittance per period is well known. However, the DBA has the advantage of greater number of ID straight sections for the users and maybe easier to tune the dispersive section for reduced chromatic sextupole strength. We present a comparison of these lattices based on optimization of the non-linear driving terms using high order achromatic cancellation of driving terms of the nonlinear lattice.
Date: June 26, 2006
Creator: KRAMER, S.L.; KRINSKY, S. & BENGTSSON, J.
Partner: UNT Libraries Government Documents Department

Development of gelcasting for industrial applications

Description: This Cooperative Research and Development Agreement (CRADA) was undertaken to assess the applicability of gelcasting for industrial production. The CRADA was amended to reflect development activity related to a new production component, an alumina Y-bar wafer support used in the silicon microcircuit manufacturing industry. This CRADA was terminated with no significant technical accomplishments completed.
Date: November 1, 1997
Creator: Nunn, S.D. & Ghinazzi, J.
Partner: UNT Libraries Government Documents Department

First Results for a Novel Superconducting Imaging-Surface Sensor Array

Description: A superconducting imaging-surface system was constructed using 12 coplanar thin-film SQUID magnetometers located parallel to and spaced 2 cm from a 25 cm diameter lead imaging-plane. Some measurements included two additional sensors on the ''back'' side of the superconducting imaging-plane to study the field symmetry for our system. Performance was measured in a shielded can and in the open laboratory environment. Data from this system has been used to: (a) understand the noise characteristics of the dewar-SQUID imaging plate arrangement, (b) to verify the imaging principle, (c) measure the background rejection factor of the imaging plane, and (d) compare superconducting materials for the imaging plane. A phantom source field was measured at the sensors as a function of phantom distance from the sensor array to verify the imaging theory. Both the shape and absolute value of the measured and predicted curves agree very well indicating the system is behaving as a gradiometer in accordance with theory. The output from SQUIDs located behind the imaging surface that sense background fields can be used for software or analog background cancellation. Fields arising from sources close to the imaging plane were shielded form the background sensors by more than a factor of 1000. Measurement of the symmetry of sensor sensitivity to uniform fields exactly followed theoretical predictions.
Date: September 13, 1998
Creator: Kraus, R.R.; Flynn, E.R.; Espy, M.A.; Matlashov, A.; Overton, W.; Peters, M.V. et al.
Partner: UNT Libraries Government Documents Department

Summary audit report on lessons learned from the Superconducting Super Collider Project

Description: In October 1993, the Congress decided to terminate the Superconducting Super Collider (SSC) project after expending about $1.57 billion on the project. While both internal and external factors contributed to the demise of the project, its cancellation offers the Department a unique opportunity to analyze what went wrong, correct the mistakes, and apply the lessons learned to future large-scale projects.
Date: April 23, 1996
Partner: UNT Libraries Government Documents Department

Anomalies on orbifolds

Description: We discuss the form of the chiral anomaly on an S1/Z2 orbifold with chiral boundary conditions. We find that the 4-divergence of the higher-dimensional current evaluated at a given point in the extra dimension is proportional to the probability of finding the chiral zero mode there. Nevertheless the anomaly, appropriately defined as the five dimensional divergence of the current, lives entirely on the orbifold fixed planes and is independent of the shape of the zero mode. Therefore long distance four dimensional anomaly cancellation ensures the consistency of the higher dimensional orbifold theory.
Date: March 16, 2001
Creator: Arkani-Hamed, Nima; Cohen, Andrew G. & Georgi, Howard
Partner: UNT Libraries Government Documents Department

PHYSICS OF OFF-AXIS ELECTRON CYCLOTRON CURRENT DRIVE

Description: Electron cyclotron current drive is a key option for driving current off-axis in a tokamak, as needed for example for current profile control or for suppression of neoclassical tearing modes. Experiments in DIII-D at low beta have shown that the partial cancellation of the Fisch-Boozer co-current by the Ohkawa counter-current can cause strong deterioration of the current drive efficiency at larger minor radius. However, more recent experiments at higher power have shown that the loss in efficiency can be mostly recovered if the target plasma has higher electron beta, {beta}{sub e}. The improvement in efficiency with beta can be understood from a theoretical viewpoint by applying the Fokker-Planck code CQL3D, which shows excellent agreement with experiment over a wide range of parameters, thereby validating the code as an effective means of predicting the ECCD.
Date: July 1, 2002
Creator: PRATER, R.; PETTY, C.C.; HARVEY, R.; LIN-LIU, Y.R.; LOHR, J.M. & LUCE, T.C.
Partner: UNT Libraries Government Documents Department

River Protection Project (RPP) Immobilized Low Activity Waste (ILAW) Disposal Plan

Description: This document replaces HNF-1517, Rev 2 which is deleted. It incorporates updates to reflect changes in programmatic direction associated with the vitrification plant contract change and associated DOE/ORP guidance. In addition it incorporates the cancellation of Project W-465, Grout Facility, and the associated modifications to Project W-520, Immobilized High-Level Waste Disposal Facility. It also includes document format changes and section number modifications consistent with CH2M HILL Hanford Group, Inc. procedures.
Date: September 22, 2000
Creator: BRIGGS, M.G.
Partner: UNT Libraries Government Documents Department

Cancellation Effects in CSR Induced Bunch Transverse Dynamics in Bends

Description: The partial cancellation between the effect of centrifugal space charge force on transverse bunch dynamics and the potential energy effect has been a long-standing controversial issue in the study of coherent synchrotron radiation (CSR) induced bunch dynamics in bends. In this paper, we clarify our definition of the ''centrifugal space charge force,'' and discuss the meaning of the ''cancellation effect'' and its general application. We further use simulation to demonstrate the cancellation in both steady state and transient regimes, and show the behavior of the effective transverse force.
Date: June 1, 2002
Creator: Li, R.
Partner: UNT Libraries Government Documents Department

Studying Gaugino mass in Semi-Direct Gauge Mediation

Description: We study gaugino mass generation in the context of semi-direct gauge mediation models, where the messengers are charged under both the hidden sector and the standard model gauge groups while they do not play important roles in dynamical supersymmetry breaking. We clarify the cancellation of the leading contributions of the supersymmetry breaking effects to the gaugino mass in this class of models in terms of the macroscopic effective theory of the hidden sector dynamics. We also consider how to retrofit the model so that we obtain the non-vanishing leading contribution to the gaugino mass.
Date: June 11, 2010
Creator: Ibe, M.; /SLAC; Izawa, K.-I.; /Kyoto U., Yukawa Inst., Kyoto /Tokyo U., IPMU; Nakai, Y.; /Kyoto U., Yukawa Inst., Kyoto et al.
Partner: UNT Libraries Government Documents Department

Dynamic X-Y Crosstalk / Aliasing Errors of Multiplexing BPMs

Description: Multiplexing Beam Position Monitors are widely used for their simplicity and inherent drift cancellation property. These systems successively feed the signals of (typically four) RF pickups through one single detector channel. The beam position is calculated from the demultiplexed base band signal. However, as shown below, transverse beam motion results in positional aliasing errors due to the finite multiplexing frequency. Fast vertical motion, for example, can alias into an apparent, slow horizontal position change.
Date: August 9, 2005
Creator: Straumann, T.
Partner: UNT Libraries Government Documents Department

ADJUSTED FIELD PROFILE FOR THE CHROMATICITY CANCELLATION IN FFAG ACCELERATORS.

Description: In an earlier report they have reviewed four major rules to design the lattice of Fixed-Field Alternating-Gradient (FFAG) accelerators. One of these rules deals with the search of the Adjusted Field Profile, that is the field non-linear distribution along the length and the width of the accelerator magnets, to compensate for the chromatic behavior, and thus to reduce considerably the variation of betatron tunes during acceleration over a large momentum range. The present report defines the method for the search of the Adjusted Field Profile.
Date: October 13, 2004
Creator: RUGGIERO, A. G.
Partner: UNT Libraries Government Documents Department

Novel Geometries for the LHC Crab Cavity

Description: The planned luminosity upgrade to LHC is likely to necessitate a large crossing angle and a local crab crossing scheme. For this scheme crab cavities align bunches prior to collision. The scheme requires at least four such cavities, a pair on each beam line either side of the interaction point (IP). Upstream cavities initiate rotation and downstream cavities cancel rotation. Cancellation is usually done at a location where the optics has re-aligned the bunch. The beam line separation near the IP necessitates a more compact design than is possible with elliptical cavities such as those used at KEK. The reduction in size must be achieved without an increase in the operational frequency to maintain compatibility with the long bunch length of the LHC. This paper proposes a suitable superconducting variant of a four rod coaxial deflecting cavity (to be phased as a crab cavity), and presents analytical models and simulations of suitable designs.
Date: May 23, 2010
Creator: B. Hall, G. Burt, C. Lingwood, R. Rimmer, H. Wang
Partner: UNT Libraries Government Documents Department