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Selective Versus Wholesale Error Correction of Grammar and Usage in the Papers of Adult Intermediate Level ESL Writing Students

Description: Over 13-weeks a control group (n=7) had all errors corrected, while an experimental group (n=9) had only article and sentence construction (run-on sentences, fragments, comma splices) errors corrected. Separating the two types of errors is essential, since the latter (representing grammar) are subject to theories of acquisition and the former (representing usage) are not. One-way analyses of variance ran on pretest versus posttest found no significant difference in either groups' article errors; however, the experimental group had significantly fewer sentence construction errors, implying that teachers should be sensitive to both the correction technique and error type; researchers should not combine the two error types in gathering data.
Date: August 1990
Creator: Whitus, Jerry D. (Jerry Dean)
Partner: UNT Libraries
open access

Blockage Corrections for Three-Dimensional-Flow Closed-Throat Wind Tunnels, With Consideration of the Effect of Compressibility

Description: "Theoretical blockage corrections are presented for a body of revolution and for a three-dimensional unswept wing in a circular or rectangular wind tunnel. The theory takes account of the effects of the wake and of the compressibility of the fluid, and is based on the assumption that the dimensions of the model are small in comparison with those of the tunnel throat. Formulas are given for correcting a number of the quantities, such as dynamic pressure and Mach number, measured in wing-tunnel tests. The report presents a summary and unification of the existing literature on the subject" (p. 771).
Date: 1950
Creator: Herriot, John G.
Partner: UNT Libraries Government Documents Department
open access

Determination of Jet-Boundary Corrections to Cowling-Flap-Outlet Pressures by an Electrical Analogy Method

Description: Report presenting corrections to the velocities near a cowling-flap tip in order to determine jet-boundary corrections to cowling-flap-outlet pressures. The presence of the low-energy air leaving the flap opening was taken into account by so shaping the nacelle model that its outer surface represented the stream surface leaving the flap tip. Copper was found unsatisfactory for use as electrode material.
Date: February 1944
Creator: Katzoff, S. & Finn, Robert S.
Partner: UNT Libraries Government Documents Department
open access

Charts for Determining Jet-Boundary Corrections for Complete Models in 7- by 10-Foot Closed Rectangular Wind Tunnels

Description: Report presenting calculations of numerical values of the jet-boundary corrections to the angle of attack and the induced-drag, rolling-moment, and yawing-moment coefficients for complete airplane or wing models in 7- by 10-foot closed rectangular wind tunnels. The results showed that the wing area was the most important variable, as has usually been assumed in previous calculations. When the corrections were based on wing area, the effect of most of the other variables was negligible.
Date: September 1945
Creator: Gillis, Clarence L.; Polhamus, Edward C. & Gray, Joseph L., Jr.
Partner: UNT Libraries Government Documents Department
open access

Jet-Boundary-Induced-Upwash Velocities for Swept Reflection-Plane Models Mounted Vertically in 7- by 10-Foot, Closed, Rectangular Wind Tunnels

Description: Note presenting numerical values of the calculated boundary-induced-upwash velocities necessary for the determination of the jet-boundary corrections for swept reflection-plane models mounted vertically in 7- by 10-foot, closed, rectangular wing tunnels in chart form. Results regarding the correction factors for accurate calculations are also provided.
Date: November 1948
Creator: Polhamus, Edward C.
Partner: UNT Libraries Government Documents Department
open access

Correction of Downwash in Wind Tunnels of Circular and Elliptic Sections

Description: The downwash velocity distribution behind the wing was determined for the free jet and for the closed tunnel of both circular and elliptic cross sections. The wing was placed at the center of the tunnel. The theory makes it possible to determine the downwash at any point in the jet. The computations were performed for points in the plane determined by the jet axis and the center-of-pressure line of the wing.
Date: July 1936
Creator: Lotz, Irmgard
Partner: UNT Libraries Government Documents Department
open access

Wind-Tunnel Corrections at High Subsonic Speeds Particularly for an Enclosed Circular Tunnel

Description: A review of existing publications on wind-tunnel corrections is followed by an approximate method for determining the corrections due to model and wake displacement and to lift. Relations are investigated for fuselages and wings of various spans in closed circular tunnels. A comparison is made between the computations and the tests in the DVL high-speed wind tunnel.
Date: February 1952
Creator: Göthert, Bernhard Hermann
Partner: UNT Libraries Government Documents Department
open access

Viscosity Corrections to Cone Probes on Rarefied Supersonic Flow at a Nominal Mach Number of 4

Description: Note presenting data obtained for the viscosity corrections to cone probes in supersonic rarefied air flow at a nominal Mach number of 4. The test models consisted of a set of seven geometrically similar 5 degree semivertex-angle cones. Results regarding cone surface pressure distributions, calibration data for geometrically similar cones, orifices size effect, and tests at other Mach numbers are provided.
Date: November 1954
Creator: Talbot, L.
Partner: UNT Libraries Government Documents Department
open access

Jet-boundary corrections for complete and semispan swept wings in closed circular wind tunnels

Description: Report presenting tables and curves that give values of the induced-upwash-velocity factors, due to jet boundary, at the horizontal center plane of a closed circular wind tunnel and of a closed bipolar wing tunnel. The application of induced-upwash-velocity factors to the determination of jet-boundary corrections is also discussed.
Date: September 1951
Creator: Sivells, James C. & Salmi, Rachel M.
Partner: UNT Libraries Government Documents Department
open access

Linear Coupling Correction With N-Turn Maps.

Description: The linear one-turn map of a storage ring contains coupling information on which a correction algorithm can be based. In principal, the one-turn matrix can be fitted from turn-by-turn data of beam position monitors after a kick was applied. However, the so obtained coupling information often sinks into the noise floor. The signal-to-noise ratio of the coupling information can be greatly enhanced by fitting maps for larger turn numbers N, equal to half the beat period. With the so obtained N-turn map an automated global coupling correction is possible without the need for a tune change. This is demonstrated for the Relativistic Heavy Ion Collider where the algorithm is implemented for operational use at injection.
Date: May 12, 2003
Creator: Fischer, Wolfram
Partner: UNT Libraries Government Documents Department
open access

Global DC closed orbit correction experiment on the NSLS x-ray ring

Description: In this note are described the global DC closed orbit correction experiments conducted on the X-ray ring at National Synchrotron Light Source (NSLS). The beam response matrix, defined as beam motion at BPM locations per unit kick by corrector magnets, was measured and then inverted using the technique of singular value decomposition (SVD). The product of the inverted matrix and the difference orbit gives the incremental kick strengths necessary to correct the orbit. As a result, the r.m.s. orbit error around the ring was reduced from 208 {mu}m to 61 {mu}m.
Date: September 15, 1992
Creator: Chung, Y.; Decker, G. & Evans, K.
Partner: UNT Libraries Government Documents Department
open access

An atmospheric correction algorithm for remote identification of non-Lambertian surfaces and its range of validity

Description: The usefulness of remotely sensed surface data depends on the ability to correct for atmospheric pertubations on the image. An atmospheric correction algorithm has been proposed which removes atmospheric pertubations from off-nadir measured radiances at the top of the atmosphere in the visible and near-infrared wavelength region. The ability of the model to reproduce radiance distributions at the surface from radiances at the top of the atmosphere is tested and found to be better than 15%. The correction formalism requires as minimum information the total optical depth of the atmosphere and the surface albedo. In this study the accuracy of the model to assumptions about the aerosol phase function, the single-scattering albedo and the vertical profile of the optical depth is also tested.
Date: February 20, 1987
Creator: Gratzki, A. & Gerstl, S.A.W.
Partner: UNT Libraries Government Documents Department
open access

For a more perfect union : correctional reform

Description: The ACIR Library is composed of publications that study the interactions between different levels of government. This document addresses correctional reform.
Date: August 1971
Creator: United States. Advisory Commission on Intergovernmental Relations.
Partner: UNT Libraries Government Documents Department
open access

An investigation of aircraft heaters 17: experimental inquiry into steady state unidirectional heat-meter corrections

Description: Report divided into two sections. One discusses a correction that must be applied to a heat meter when it is used at temperatures other than temperatures at which it was calibrated. The other section contains the results of an application of the two methods of correcting the heat-transfer rates for contact and heat-meter resistance to experimental data.
Date: August 1944
Creator: Boelter, L. M. K.; Poppendiek, H. F. & Gier, J. T.
Partner: UNT Libraries Government Documents Department
open access

Operations with the digital orbit feedback system in the NSLS x-ray ring

Description: The digital filtering and eigenvector decomposition-based orbit correction is performed by two dedicated HP 742/743 rt micros which communicate with Motorola CPU based orbit-measuring and orbit-correction systems. The correction algorithm in the DFbk was orthogonalized with respect of the analog global harmonic feedback. Operational results concerning improvements in the noise suppression at low frequencies and especially in the dc drift as well as in the orbit stability are shown. Efforts are underway to improve the resolution of the orbit measuing system and the sampling rate using 16 bit 400 kHz ADC`s which will allow orbit sampling with high resolution at 4 kHz frequency.
Date: May 1, 1996
Creator: Bozoki, E.; Rammamorthy, S.; Singh, O.; Tang, Y. & Friedman, A.
Partner: UNT Libraries Government Documents Department
open access

Alpha Dithering to Correct Low-Opacity 8 Bit Compositing Errors

Description: This paper describes and analyzes a dithering technique for accurately specifying small values of opacity ({alpha}) that would normally not be possible because of the limited number of bits available in the alpha channel of graphics hardware. This dithering technique addresses problems related to compositing numerous low-opacity semitransparent polygons to create volumetric effects with graphics hardware. The paper also describes the causes and a possible solution to artifacts that arise from parallel or distributed volume rendering using bricking on multiple GPU's.
Date: March 31, 2003
Creator: Williams, P L; Frank, R J & LaMar, E C
Partner: UNT Libraries Government Documents Department
open access

Jet-Boundary Corrections to the Downwash Behind Powered Models in Rectangular Wind Tunnels With Numerical Values for 7- by 10-Foot Closed Wind Tunnels

Description: Report presenting methods for determining the jet-boundary corrections to the downwash behind models in rectangular wind tunnels. The methods take into account the tunnel dimensions, the type of jet, the span loading of the model, the geometric position of the wind and of the tail in the tunnel, the displacement of the wing wake, and the effect of the slipstream.
Date: August 1942
Creator: Swanson, Robert S. & Schuldenfrei, Marvin J.
Partner: UNT Libraries Government Documents Department
open access

Jet-Boundary Corrections to a Yawed Model in a Closed Rectangular Wind Tunnel

Description: Report presenting general formulas for determining the jet-boundary corrections to the angle of attack, the drag coefficient, the downwash, the pitching, rolling, and yawing-moment coefficients of complete powered yawed models, and to the increments of rolling and yawing-moment coefficients due to the ailerons on yawed models.
Date: February 1943
Creator: Swanson, Robert S.
Partner: UNT Libraries Government Documents Department
open access

Correction of vertical crossing induced dispersion in LHC

Description: Beam crossing schemes in the LHC interaction regions impose non-zero vertical closed orbit in the low-{beta} triplets, which excite a perturbative periodic dispersion ; the phenomenon is described and quantified in detail. It is shown that this dispersion reaches values at the limit of tolerances in the nominal optics of Version 5.0 of the LHC ring, and prohibitively large values in particular in the low- {beta} quadrupoles and interaction regions in the foreseen extreme {beta}-squeeze case ({beta}{sup *} = 0.25 m). Such behaviour justifies including a local correction in the LHC design, in order to damp the effect and confine it as much as possible in the vicinity of the excitation sources (the low-{beta} triplets). An optical compensation scheme based on the use of skew quadrupoles is described in detail, as well as the entailed residual dispersion.
Date: November 1, 1997
Creator: Meot, F.
Partner: UNT Libraries Government Documents Department
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