Practical method of calculation of a foundation strip on a nonlinearly deformable bed

Background: The visibility, vulnerability and social stigmata of facial scars whether by burn, nevi or trauma can be compelling for the patient as well as challenging for the surgeon. Restoration to normal form and aesthetics require tissue replacement which has good colour and texture match and produce minimal visible scarring. Although many other options are available for a given defect, tissue expansion offers the best alternative which meets almost all the criteria of an ideal procedure.Methods: Among 92 patients with deformities over various facial subunits were operated and expanders 50 ml to 300 ml inserted subcutaneously adjacent to the scar. Prior planning, accurate measurement and choice of ideal expander is extremely important. A precise and practical method of calculation for determination of amount and duration of expander was used. Any secondary deformity to adjoining vital structures was avoided.Results: Results were meticulously and critically analyzed. Different shapes, dimensions and volume of expanders were used depending on the anatomical site which was to be expanded. A total of 118 expanders were inserted in 92 patients. The average volume of tissue expanders used was 170.33 ml. Majority of the expanders used had volume of 200 ml (62.71%). Post-expansion volume was 240.67 ml and the over expansion done was 41.3% over the pre-expansion volume of 170.33 ml. Surgical outcome and cosmesis was assessed by the patient’s perspective and was considered fair by 57.61% patients.Conclusions: The study underlines the clinical application, reasons for overexpansion as well as shortcomings and complications of tissue expansion.

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PRACTICAL METHOD OF CALCULATION OF REINFORCEMENT OF STEEL PURLINS AND BEAMS BY INSTALLATION OF TWO ELASTIC SUPPORTS IN SPAN

Urban development and spatial planning ◽

10.32347/2076-815x.2019.71.46-52 ◽

2019 ◽

Vol 0 (71) ◽

pp. 46-52

Author(s):

Pavlo Babichev ◽

Oleksandr Glitin ◽

Serhii Radetskyi

Keyword(s):

Practical Method ◽

Elastic Supports ◽

Method Of Calculation

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PRACTICAL METHOD OF CALCULATION FOR THE ULTIMATE STRENGTH OF STIFFENED PLATES UNDER COMPRESSION

Proceedings of the Japan Society of Civil Engineers ◽

10.2208/jscej1969.1980.302_1 ◽

1980 ◽

Vol 1980 (302) ◽

pp. 1-13

Author(s):

Sadao KOMATSU ◽

Toshiyuki KITADA

Keyword(s):

Ultimate Strength ◽

Practical Method ◽

Stiffened Plates ◽

Method Of Calculation

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Calculation of Noise Components for Bidirectional Path Tracing with Photon Maps

10.51130/graphicon-2020-2-4-2 ◽

2020 ◽

pp. short2-1-short2-6

Author(s):

Sergey Ershov ◽

Elisey Birukov ◽

Alexey Voloboy ◽

Vladimir Galaktionov

Keyword(s):

Monte Carlo ◽

Ray Tracing ◽

Root Mean Square ◽

Practical Method ◽

Mean Square ◽

Powerful Method ◽

Optimal Parameters ◽

Method Of Calculation ◽

Path Tracing ◽

Light Rays

The classic Monte-Carlo ray tracing is a powerful method which allows to simulate virtually all effects in ray optics, but it may be inadmissibly slow for many cases, such as calculation of images seen by a lens or pin-hole camera. In this cases another stochastic method is more efficient such as the bi-directional ray Monte-Carlo tracing with photon maps (BDPM). The level of noise i.e. the r.m.s. (root mean square) of pixel luminance calculated in one iteration of the method, depends on various parameters of the method, such as the number of light and camera paths, radius of integration sphere etc. so it is desirable to be able to predict this dependence to choose optimal parameters of the method. It was shown that this r.m.s is a sum of 3 functions scaled by reverse number of camera and light rays. These functions themselves are independent of the number of rays, so knowing them one can predict the noise for any number of rays and thus find the optimal one. These functions are a sort of correlations and their calculation from ray tracing is not a trivial problem. In this paper we describe a practical method of calculation and demonstrate the usage of its results for the choice of ray number.

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The role of differential phase contrast in electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108027 ◽

1978 ◽

Vol 36 (1) ◽

pp. 176-177

Author(s):

E.M. Waddell ◽

J.N. Chapman ◽

R.P. Ferrier

Keyword(s):

Phase Contrast ◽

Practical Method ◽

Position Vector ◽

Differential Phase ◽

Pure Phase ◽

Differential Phase Contrast ◽

The Difference ◽

Image Position ◽

First Moment

Dekkers and de Lang (1977) have discussed a practical method of realising differential phase contrast in a STEM. The method involves taking the difference signal from two semi-circular detectors placed symmetrically about the optic axis and subtending the same angle (2α) at the specimen as that of the cone of illumination. Such a system, or an obvious generalisation of it, namely a quadrant detector, has the characteristic of responding to the gradient of the phase of the specimen transmittance. In this paper we shall compare the performance of this type of system with that of a first moment detector (Waddell et al.1977).For a first moment detector the response function R(k) is of the form R(k) = ck where c is a constant, k is a position vector in the detector plane and the vector nature of R(k)indicates that two signals are produced. This type of system would produce an image signal given bywhere the specimen transmittance is given by a (r) exp (iϕ (r), r is a position vector in object space, ro the position of the probe, ⊛ represents a convolution integral and it has been assumed that we have a coherent probe, with a complex disturbance of the form b(r-ro) exp (iζ (r-ro)). Thus the image signal for a pure phase object imaged in a STEM using a first moment detector is b2 ⊛ ▽ø. Note that this puts no restrictions on the magnitude of the variation of the phase function, but does assume an infinite detector.

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