Comparison of a New Method for Measuring Aircraft Power and Drag in Flight with a Standard Technique

1977 ◽  
Author(s):  
Frederick O. Smetana ◽  
Stan R. Fox
Keyword(s):  
Standard Technique ◽  
New Method

Corrective osteotomy of distal radial deformities: a new method of guided locking fixed screw positioning

2011 ◽  
Vol 38 (1) ◽  
pp. 29-34 ◽  
Author(s):  
M. Farshad ◽  
F. Hess ◽  
L. Nagy ◽  
A. Schweizer
Keyword(s):  
Distal Radius ◽  
Locking Plate ◽  
Corrective Osteotomy ◽  
Standard Technique ◽  
New Method ◽  
New Technique ◽  
Clinical Use ◽  
Volar Locking Plate ◽  
New Device ◽  
Radial Inclination

Corrective osteotomy for distal radial malunion is a valuable but at times technically challenging operation. We have developed a new device to aid in the performance of the operation. We compared clinical use of the new technique with the standard technique. In 11 patients treated with the new technique the volar locking plate needed repositioning only once. With the standard technique in 17 patients the plate was repositioned in nine cases and needed bending in six cases. The new method corrected radial inclination (SD of 3° vs. 9°) and ulnar variance (SD of 0.9 mm vs. 1.4 mm) more predictably than the standard technique but there was no advantage in correction of volar tilt (SD of 6° vs. 4°). In our experience the new device makes corrective osteotomy of the distal radius easier and more reliable.

scholarly journals Laue-DIC: a new method for improved stress field measurements at the micrometer scale

2015 ◽  
Vol 22 (4) ◽  
pp. 980-994 ◽  
Author(s):  
J. Petit ◽  
O. Castelnau ◽  
M. Bornert ◽  
F. G. Zhang ◽  
F. Hofmann ◽  
...  
Keyword(s):  
Standard Technique ◽  
Field Measurements ◽  
European Synchrotron Radiation Facility ◽  
Image Correlation ◽  
New Method ◽  
Polycrystalline Materials ◽  
Element Analysis ◽  
Analytical Functions ◽  
Local Stresses ◽  
Micrometer Scale

A better understanding of the effective mechanical behavior of polycrystalline materials requires an accurate knowledge of the behavior at a scale smaller than the grain size. The X-ray Laue microdiffraction technique available at beamline BM32 at the European Synchrotron Radiation Facility is ideally suited for probing elastic strains (and associated stresses) in deformed polycrystalline materials with a spatial resolution smaller than a micrometer. However, the standard technique used to evaluate local stresses from the distortion of Laue patterns lacks accuracy for many micromechanical applications, mostly due to (i) the fitting of Laue spots by analytical functions, and (ii) the necessary comparison of the measured pattern with the theoretical one from an unstrained reference specimen. In the present paper, a new method for the analysis of Laue images is presented. A Digital Image Correlation (DIC) technique, which is essentially insensitive to the shape of Laue spots, is applied to measure the relative distortion of Laue patterns acquired at two different positions on the specimen. The new method is tested on anin situdeformed Si single-crystal, for which the prescribed stress distribution has been calculated by finite-element analysis. It is shown that the new Laue-DIC method allows determination of local stresses with a strain resolution of the order of 10−5.

Creep Relaxation of Residual Stresses Around Cold Expanded Holes

2000 ◽  
Vol 123 (1) ◽  
pp. 125-131 ◽  
Author(s):  
A. A. Garcia-Granada ◽  
V. D. Lacarac ◽  
P. Holdway ◽  
D. J. Smith ◽  
M. J. Pavier
Keyword(s):  
Finite Element ◽  
Residual Stresses ◽  
Mechanical Load ◽  
Three Dimensional ◽  
Standard Technique ◽  
New Method ◽  
Near Surface ◽  
Cold Expansion ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element

The cold expansion of fastener holes in aircraft components is a standard technique to improve fatigue life. There is concern that the beneficial residual stresses arising from cold expansion may relax due to creep. This paper describes experimental measurement and finite element prediction of cold expansion residual stresses and their redistribution after creep, with and without additional mechanical load. Experimental measurements of near-surface stresses used an X-ray diffraction technique while average through-the-thickness stresses were measured using a new method based on Sachs’ boring. This new method allowed non-axisymmetric residual stresses to be measured, as was the case when creep relaxation occurred with mechanical load. Axisymmetric and three dimensional finite element analyses were used to predict the stress distribution through the thickness of the component showing good agreement with measurement. Creep relaxation of residual stress does indeed occur, but some benefit of the cold expansion remains, particularly when creep relaxation is combined with the application of mechanical load.

scholarly journals Histochemical demonstration of unsaturated hydrophilic lipids with palladium chloride.

1977 ◽  
Vol 25 (3) ◽  
pp. 200-205 ◽  
Author(s):  
J A Kiernan
Keyword(s):  
Solvent Extraction ◽  
Standard Technique ◽  
Histochemical Demonstration ◽  
New Method ◽  
Histochemical Method ◽  
Palladium Chloride ◽  
Unsaturated Lipids ◽  
Metallic Palladium

Compounds in which olefinic linkages are accessible to aqueous reagents reduce the chloropalladite ion [PdCl4]2-, to metallic palladium. This reaction is used in a histochemical method whereby hydrophilic unsaturated lipids are stained dark brown or black. The specificity of the new method has been confirmed by means of solvent-extraction and chemical blocking procedures and by comparison with other histochemical techniques. Yellow staining of collagen, keratin and cytoplasm is probably due to attachment of the chloropalladite anion to proteins. The yellow background can be largely decolorized by treating the sections with aqueous pyridine, which forms colorless complexes with divalent palladium. A standard technique for staining with palladium is presented and the method is discussed in relation to other histochemical procedures that demonstrate unsaturated lipids.

Selective Sampling and Orientation of Non-Homogeneous Tissues

1968 ◽  
Vol 26 ◽  
pp. 98-99
Author(s):  
C. C. Clawson ◽  
L. W. Anderson ◽  
R. A. Good
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Light Microscopy ◽  
Random Sampling ◽  
New Method ◽  
Microscope Examination ◽  
Small Areas ◽  
Selective Sampling ◽  
Large Numbers ◽  
Specific Orientation

Investigations which require electron microscope examination of a few specific areas of non-homogeneous tissues make random sampling of small blocks an inefficient and unrewarding procedure. Therefore, several investigators have devised methods which allow obtaining sample blocks for electron microscopy from region of tissue previously identified by light microscopy of present here techniques which make possible: 1) sampling tissue for electron microscopy from selected areas previously identified by light microscopy of relatively large pieces of tissue; 2) dehydration and embedding large numbers of individually identified blocks while keeping each one separate; 3) a new method of maintaining specific orientation of blocks during embedding; 4) special light microscopic staining or fluorescent procedures and electron microscopy on immediately adjacent small areas of tissue.

The Analysis of Dislocations Using a Symmetry Criterion

1972 ◽  
Vol 30 ◽  
pp. 660-661
Author(s):  
J. C. Ingram ◽  
P. R. Strutt ◽  
Wen-Shian Tzeng
Keyword(s):  
Electron Beam ◽  
Electron Microscope ◽  
Displacement Field ◽  
Standard Technique ◽  
Residual Image ◽  
Symmetry Criterion

The invisibility criterion which is the standard technique for determining the nature of dislocations seen in the electron microscope can at times lead to erroneous results or at best cause confusion in many cases since the dislocation can still show a residual image if the term is non-zero, or if the edge and screw displacements are anisotropically coupled, or if the dislocation has a mixed character. The symmetry criterion discussed below can be used in conjunction with and in some cases supersede the invisibility criterion for obtaining a valid determination of the nature of the dislocation.The symmetry criterion is based upon the well-known fact that a dislocation, because of the symmetric nature of its displacement field, can show a symmetric image when the dislocation is correctly oriented with respect to the electron beam.

Stereo imaging in the shadow electron microscope

1978 ◽  
Vol 36 (1) ◽  
pp. 120-121
Author(s):  
W. C. T. Dowell
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Convenient Method ◽  
Patent Application ◽  
Standard Technique ◽  
Stereo Imaging ◽  
Stereo Images ◽  
Specimen Height

Stereo imaging is not new to electron microscopy. Von Ardenne, who first published transmission pairs nearly forty hears ago, himself refers to a patent application by Ruska in 1934. In the early days of the electron microscope von Ardenne employed a pair of magnetic lenses to view untilted specimens but soon opted for the now standard technique of tilting the specimen with respect to the beam.In the shadow electron microscope stereo images can, of course, be obtained by tilting the specimen between micrographs. This obvious method suffers from the disadvantage that the magnification is very sensitive to small changes in specimen height which accompany tilting in the less sophisticated stages and it is also time consuming. A more convenient method is provided by horizontally displacing the specimen between micrographs. The specimen is not tilted and the technique is both simple and rapid, stereo pairs being obtained in less than thirty seconds.

A new method for the determination of nitrates

1960 ◽  
Vol 23 ◽  
pp. 227-232 ◽  
Author(s):  
P WEST ◽  
G LYLES
Keyword(s):  
New Method
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