XXVI.—A New Method of determining the Degree of Twist in Single Threads

1907 ◽  
Vol 27 ◽  
pp. 264-268 ◽  
Author(s):  
Thomas Oliver

The determination of the degree of twist in a folded or ply thread composed of two or more strands is an easy matter. It is merely necessary to stretch the thread between two clamps, one being fixed and the other forming the end of a bar which can be rotated about its axis. A counter is attached to indicate the number of rotations. Rotating the thread in the opposite direction to its twist ultimately brings the singles parallel to each other. This point is easily observed. If we apply this method to single yarns we are at once confronted with the difficulty that the fibres constituting the yarn cannot be reduced to exact parallelism with each other.

Author(s):  
Jian-Qing Zhang ◽  
Ting-Li Yang

Abstract This work presents a new method for kinetostatic analysis and dynamic analysis of complex planar mechanisms, i.e. the ordered single-opened-chains method. This method makes use of the ordered single-opened chains (in short, SOC,) along with the properties of SOC, and the network constraints relationship between SOC,. By this method, any planar complex mechanism can be automatically decomposed into a series of the ordered single-opened chains and the optimal structural decomposition route (s) can be automatically selected for dynamic analysis, the paper present the dynamic equation which can be used to solve both the kinetostatic problem and the general dynamic problem. The main advantage of the proposed approach is the possibility to reduce the number of equations to be solved simultaneously to the minimum, and its high automation as well. The other advantage is the simplification of the determination of the coefficients in the equations, and thus it maybe result in a much less time-consuming algorthem. The proposed approach is illustrated with three examples. The presented method can be easily extended to the dynamic analysis of spatial mechanisms.


1990 ◽  
Vol 192 ◽  
Author(s):  
G. Amato ◽  
L. Boarino ◽  
F. Fizzotti ◽  
C. Manfredotti

ABSTRACTWe propose to apply a new method to model the optical response of amorphous silicon thin films. This method presents the advantage of having a good physical insight. On the other hand, although the model has been originally tested on different materials like a-Si, a-Ge and a-GaAs, we show that it is also sensitive to small differences like those that can exist between intrinsic and doped a-Si:H.


Geophysics ◽  
1948 ◽  
Vol 13 (1) ◽  
pp. 92-97
Author(s):  
Sulhi Yüngül

In two papers published in Geophysics, one in the October, 1944, issue and the other in October, 1946, a system and method of calculation, called “Resistolog” method, was presented. The object of the Resistolog method is to eliminate the effects of superficial inhomogeneities which are the most troublesome obstacles in interpreting electrical sounding results in exploring deep, horizontal discontinuities. The following is a discussion of the papers mentioned above, mainly of the subject of (1) the apparent‐resistivity formula derived for use with the Resistolog configuration, (2) determination of inflectional points on apparent resistivity curves, (3) depth of penetration, and (4) distortion caused by the “far electrode.” A new method to determine inflectional points is also given. This paper includes a comprehensive knowledge about the forementioned papers and the reader may not have to refer to them.


2005 ◽  
Vol 85 (6) ◽  
pp. 1441-1447 ◽  
Author(s):  
Nadine M. Johnston ◽  
David A. Ritz

The phenomenon of adoption, i.e. replacement of larvae prematurely liberated from the brood pouch of conspecifics, and kin recognition was examined in three mysid species found commonly in Tasmanian waters: Anisomysis mixta australis, Paramesopodopsis rufa and Tenagomysis tasmaniae. A new method for testing the incidence of adoption using fluoroscein dye, which enables the determination of ‘same stage’ adoptions, is described. Under field and laboratory conditions, all species practised intraspecific adoption into their own brood pouches. Under laboratory conditions the incidence of adoption was higher in T. tasmaniae than it was in the other two species. Tenagomysis tasmaniae also adopted its own young in preference to those of a conspecific. Differences in the incidence of adoption between the three species suggests a higher degree of maternal care in T. tasmaniae than in either A. mixta australis or P. rufa and may be explained by differences in anatomy, habitat conditions and predation pressure.


1984 ◽  
Vol 6 (2) ◽  
pp. 137-161 ◽  
Author(s):  
P. Van Houtte

Three series expansion methods for texture analysis from incomplete pole figures have been compared. Method I is the presently most used method, method II is a variant of it and method III is entirely new. Computer programs have been written for the three methods.Incomplete pole figures have then been prepared from known textures of f.c.c. metals. In some cases, artificial experimental errors have been simulated. These pole figures were analyzed by the three computer programs, after which the resulting texture functions were compared to the original texture functions.No significant differences were found for weak textures. On the other hand, the results of method I are much poorer than those of the two other methods for sharp textures, because it underestimates the normalisation factors.The best results were obtained by method III.


Author(s):  
D.R. Rasmussen ◽  
N.-H. Cho ◽  
C.B. Carter

Domains in GaAs can exist which are related to one another by the inversion symmetry, i.e., the sites of gallium and arsenic in one domain are interchanged in the other domain. The boundary between these two different domains is known as an antiphase boundary [1], In the terminology used to describe grain boundaries, the grains on either side of this boundary can be regarded as being Σ=1-related. For the {110} interface plane, in particular, there are equal numbers of GaGa and As-As anti-site bonds across the interface. The equilibrium distance between two atoms of the same kind crossing the boundary is expected to be different from the length of normal GaAs bonds in the bulk. Therefore, the relative position of each grain on either side of an APB may be translated such that the boundary can have a lower energy situation. This translation does not affect the perfect Σ=1 coincidence site relationship. Such a lattice translation is expected for all high-angle grain boundaries as a way of relaxation of the boundary structure.


Author(s):  
Y. Ishida ◽  
H. Ishida ◽  
K. Kohra ◽  
H. Ichinose

IntroductionA simple and accurate technique to determine the Burgers vector of a dislocation has become feasible with the advent of HVEM. The conventional image vanishing technique(1) using Bragg conditions with the diffraction vector perpendicular to the Burgers vector suffers from various drawbacks; The dislocation image appears even when the g.b = 0 criterion is satisfied, if the edge component of the dislocation is large. On the other hand, the image disappears for certain high order diffractions even when g.b ≠ 0. Furthermore, the determination of the magnitude of the Burgers vector is not easy with the criterion. Recent image simulation technique is free from the ambiguities but require too many parameters for the computation. The weak-beam “fringe counting” technique investigated in the present study is immune from the problems. Even the magnitude of the Burgers vector is determined from the number of the terminating thickness fringes at the exit of the dislocation in wedge shaped foil surfaces.


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

1977 ◽  
Vol 37 (02) ◽  
pp. 210-215 ◽  
Author(s):  
R Margalit ◽  
E Gidron ◽  
Y Shalitin

SummaryThe term “effective activator” of plasminogen is proposed, to denote the resultant of activator-antiactivator interaction, and a method for the determination of the level of these activators is described. By adding axcess plasminogen to the euglobulin fraction of plasma the influence of the level of endogenous plasminogen and of the antiplasmin is eliminated. It is shown that the level of fibrinogen has very little bearing on the results. An effective activator unit is defined as equal to 1 CTA unit of urokinase activity on a fibrinogen-plasminogen substrate.


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