Surface distortion features on indented CaF2 cleavages

Surface distortion features around static indents on the cleavages of CaF₂ single crystals have been investigated by multiple beam interference technique. At room temperature microcracks around such indents nucleate at the sinking in regions. Fizeau fringe patterns (around indents at 200° C) revealed a transition from a three-fold to a six-fold material flow.     

Bandwidth compression of noisy images

The effect of additive noise on Discrete Fourier Transform of pictorial data (2DFT) must be considered in several important problems such as filtering, enhancement and bandwidth compression. This paper investigates the statistical properties of the corrupted 2DFT coefficients, and the error involved in reconstruction when a subset of these coefficients is employed for the purpose. The latter being often the case, the present analysis provides a rational basis for frequency selection and filter specification. Application of an F-test quantifies the reliability of filtering or bandwidth compression.     

The lipids of buffalo spermatozoa and seminal plasma

An allometric method for estimating the volume change in inflamed paw of rats is described. The technique is effective and advantageous for long term observation of adjuvant arthritis which lacks a suitable reference criterion due to the simultaneous swelling of the control paw. In the present method, the inflammatory intensity (IF) of paw edema is estimated by means of the formula; IF(%)=(2Vr/cXd(I+Wt/aXb)-I) X 100 where Vt is the paw volume, Wt is the body weight weight and X is the tail length of the inflamed rat. The constants a, b, c, and d are obtained from tthe normal rats using the relative growth law, W=aXb and V=cXd (where W is the body weight, V is the paw volume and X is the tail length).     

Acoustic diffraction by a rigid annular disk

Summary The subject of this paper is the problem of acoustic diffraction by a perfectly rigid annular disk. The method of solution rests on formulating the problem in terms of an integral equation which embodies the steady state wave equation as well as the boundary conditions. This Fredholm integral equation of the first kind is converted into four simultaneous integral equations of the second kind by using Williams' integral equation technique. These four integral equations are subsequently solved by the standard iterative procedure when the frequency of the incident wave is low and the inner radius of the annulus is small.     

Einfluß des Glühens unter Spannung auf die Eigenschaften von Kaltband

Einfluß einer Zugspannung sowie der Abkühlgeschwindigkeit beim Kurzzeitglühen von beruhigten und unberuhigten Stählen auf die mechanischen Eigenschaften des Bandes, insbesondere auf die obere Streckgrenze.     

P-stable singlestep methods for periodic initial-value problems involving second-order differential equations

Summary A class of P-stable singlestep methods is discussed for solving initial-value problems involving second-order differential equations. The methods depend upon a parameter p>0 and reduce to the classical methods for p=0. A few choices of p have been discussed for which the methods are P-stable. Further, when p is chosen for linear problems as the square of the frequency of the periodic solution, the methods are P-stable. Numerical results for both linear and non-linear problems show that the P-stability is an important requirement for determining periodic numerical solutions of second-order differential equations.     

Conductivity of highly concentrated aqueous electrolyte solutions III: H2O+NH4NO3+RbNO3 system

Conductivity of H₂O+NH₄NO₃+RbNO₃ system containing up to 5.15 stoichiometric mol percent of RbNO₃ and water/ammonium nitrate mol ratio varying between 1 and 6 have been measured at temperatures ranging between 275–345 K. At all compositions, variation of conductivity with temperature deviated slightly from Arrhenius behaviour. Conductivity-composition isotherms pass through a maximum at c0.18 mol fraction of electrolyte concentration; these have been discussed using the free volume model, cooperative rearrangement theory and environmental relaxation model of liquid transport.     

Using dynamic programming for solving variational problems invision

Dynamic programming is discussed as an approach to solving variational problems in vision. Dynamic programming ensures global optimality of the solution, is numerically stable, and allows for hard constraints to be enforced on the behavior of the solution within a natural and straightforward structure. As a specific example of the approach's efficacy, applying dynamic programming to the energy-minimizing active contours is described. The optimization problem is set up as a discrete multistage decision process and is solved by a time-delayed discrete dynamic programming algorithm. A parallel procedure for decreasing computational costs is discussed