scholarly journals Optimization of the formulaof the design resistance of soil

Author(s):  
K. D. Skvortsov ◽  
◽  
A. I. Osokin ◽  

The assumptions made in the derivation of the formula for the design soil resistance are considered. It is shown that in the conditions of the plane problem, taking into account the coefficient of lateral soil pressure leads to lower values of the initial critical load and, consequently, to a decrease in the design resistance. The equation of limiting equilibrium is implemented in the MathCad software package, which makes it possible to obtain isolines of deviation angles at any depth from the applied uniformly distributed load. To determine the initial critical load, a formula is given that takes into account the coefficient of lateral soil pressure K0. In the final part of the article, the solution to the problem is given according to the formula of N. P. Puzyrevsky and according to the formula derived by the author, taking into account K0, the difference in the isolines of the deflection angles is presented, and an analysis of a similar problem in the Plaxis 2D software package is carried out.

Author(s):  
E. Völkl ◽  
L.F. Allard ◽  
B. Frost ◽  
T.A. Nolan

Off-axis electron holography has the well known ability to preserve the complex image wave within the final, recorded image. This final image described by I(x,y) = I(r) contains contributions from the image intensity of the elastically scattered electrons IeI (r) = |A(r) exp (iΦ(r)) |, the contributions from the inelastically scattered electrons IineI (r), and the complex image wave Ψ = A(r) exp(iΦ(r)) as:(1) I(r) = IeI (r) + Iinel (r) + μ A(r) cos(2π Δk r + Φ(r))where the constant μ describes the contrast of the interference fringes which are related to the spatial coherence of the electron beam, and Φk is the resulting vector of the difference of the wavefront vectors of the two overlaping beams. Using a software package like HoloWorks, the complex image wave Ψ can be extracted.


1827 ◽  
Vol 117 ◽  
pp. 286-296 ◽  

In the Philosophical Transactions for 1826, Part II. Mr. Herschel has given a detailed account of observations, which were made in the month of July, 1825, for the purpose of ascertaining the difference of the meridians of the Royal Observatories of Greenwich and Paris, with a computation of these observations, from which the most probable value of the difference of longitude appears to be 9 m 21 s. 6. But I have perceived that in the copy of the observations delivered to him from the Royal Observatory of Greenwich, an error of one second has been committed; as the true sidereal time of the observation made there on 21st July, ought to be 17 h 38 m 57·12 in place of 17 h 38 m 56 s. 10, set down in the Table p. 104, which he informs me was computed at the Observatory, and officially communicated to him from the Astronomer Royal. This error seems to have had its origin in the little Table at the bottom of page 103; for, on subtracting the error of the clock, 47 s. 37, from the time 18 h 8 m 30 s. 40, the true sidereal time is 18 h 7 m 43 s. 03, instead of 18 h 7 m 42 s. 03, there given. The error in the result of that day’s observations, arising from this cause, has been partly compensated by a mistake of three tenths of a second, which has occurred in calculating the combined observations of the same day, the gain of mean on sidereal time being stated to be — 4 s. 54 (pp. 120 and 122), in place of — 4 s. 24. On checking the other observations, a few trifling alterations appear to be necessary upon the Greenwich Table of sidereal time, from the data given along with it. These seem to be occasioned by different methods of calculation, and indeed are hardly worthy of notice. The French astronomers not having given the data on which the calculations of the sidereal times at Paris are founded, they are assumed to be correct.


The circumstances are discussed under which orthogonal relations exist between the elastic critical modes of plane frames subjected to proportional loading. Orthogonal relations may be obtained provided the loading does not produce any components of deformation associated with any of the critical modes at arbitrary levels of the load factor, and provided no part of the structure remains statically indeterminate due to bar forces when all rigid joints are replaced by pin joints. When at arbitrary load factors, the structure deforms with components associated with any of the buckling modes, the elastic failure load is not identical with the lowest elastic critical load, although for many frames the two loads may be very close. A general expression is obtained which reveals the relation between the deformations at an arbitrary load level and the deflexions given by linear analysis. The difference between the elastic failure load and the elastic critical load is discussed, and an approximate treatment applicable to certain types of frame and associated loading is developed.


2021 ◽  
Author(s):  
V.E. Dmitriyev ◽  
D.V. Popov ◽  
V.A. Shakhnov

This article deals with the digital processing of a matrix radar image. The information received from the radar scanner needs to be transformed to enable visual perception. The article describes the main methods of digital processing of matrix data, presents the images transformed by them. The aim of the article was the development of a radar data processing algorithm that identifies the contours and edges of examined objects. The authors propose an algorithm for isolating the geometric structure of the scanned area. The difference between the processing method and the known analogues is based on the nature of the change in the values of the array being processed and consists in the double operation of extracting the gradient of the distribution of values. The software implementation of the algorithm is made in C++ using methods from an open library of computer vision. The efficiency of the algorithm was estimated based on comparison with the algorithms for determining edges based on linear filtering and neural networks. The results of the work can be used to create software for mobile short-range radar devices. Imaging from object boundaries and their edges provides spatial perception of the image by the operator, and free areas are available for rendering additional information. This solution allows you to combine scanning devices and thereby increase the information value of the result.


2012 ◽  
Vol 35 (1) ◽  
pp. 27-70
Author(s):  
Björn Lundquist

It is well known that the aktionsart/lexical aspect of a predicate influences the temporal interpretation and the aspectual marking of a sentence, and also that languages differ with respect to which aktionsart properties feed into the tense-aspect system (see e.g. Bohnemeyer & Swift 2004). In this paper, I try to pin down the exact locus of variation between languages where the stative–dynamic distinction is mainly grammaticized (e.g. English, Saamáka) and languages where the telic–atelic distinction is mainly grammaticized (e.g. Swedish, Chinese and Russian). The focus will be on the differences between English and Swedish, and I will argue that these two languages crucially differ in the nature of Assertion Time (or Topic/Reference Time, Klein 1994, Demirdache & Uribe-Etxebarria 2000): whereas the assertion time in English is always punctual in imperfective contexts, assertion time in Swedish can extend to include minimal stages of events. The Assertion Time is introduced by a (viewpoint) aspect head that is present in both languages, but not phonologically realized. The difference can thus not be ascribed to the presence or absence of overt tense, aspect or verb morphology, or to a special tense value, as argued in one way or other by, for example, Giorgi & Pianesi (1997), Demirdache & Uribe-Etxebarria (2000) and Ramchand (2012). Once this factor (i.e. the nature of Assertion Time) has been isolated, it becomes evident that all verbs in English and Swedish, regardless of telicity or dynamicity, can be assigned either a perfective or an imperfective value. Moreover, I will argue that the English progressive–non-progressive (or ‘simple’) distinction is independent of viewpoint aspect (i.e. the perfective– imperfective distinction) made in, for example, the Romance languages.


1761 ◽  
Vol 52 ◽  
pp. 182-183

Having measured the diameter of Venus, on the sun, three times, with the object-glass micrometer, the mean was found to be 58 seconds; and but 6/10 of a second, the difference of the extremes.


1950 ◽  
Vol 40 (3) ◽  
pp. 199-226 ◽  
Author(s):  
E. M. Crook ◽  
D. J. Watson

Continuous records of the temperature of potatoes stored in clamps were made in 1942–3 (one clamp) and in 1943–4 (three clamps). In the first year, the temperatures at various positions in the clamp coverings were also recorded.The temperature at the middle of the potato heap showed a drift with time similar to that of mean air temperature. Deviations of mean air temperature from smooth trend, lasting for about a week, had no effect on the temperature of the potatoes; longerperiod deviations were reflected in the temperature of the potatoes after a lag of about a week. The difference in weekly mean temperature between potatoes and external air averaged about 1–5° C. in 1943–4. In 1942–3 it was greater, increasing to over 20° C. in April, because bacterial rotting of the potatoes following blight infection increased the rate of heat production and caused the clamp to collapse at the end of April.


2015 ◽  
Vol 9 (1) ◽  
pp. 1-16 ◽  
Author(s):  
Tamgid Ahmed Chowdhury

Purpose – This paper aims to argue that the traditional belief that “consumer ethnocentrism is a phenomenon of the developed countries only” is no longer true. To establish this argument, our study assesses the applicability of the Consumer Ethnocentric Tendencies Scale (CETSCALE) in Bangladesh by judging the unidimensionality feature of the same. Design/methodology/approach – The methodology is based on sample of 788 respondents collected from 27 border and non-border districts of Bangladesh. Findings – Statistically significant results show that for the consumers of border and non-border districts, the original CETSCALE is, to a great extent, applicable as those groups have shown positive attitudes in retaining 12-14 items out of the 17 items of the original scale. However, the groups and the respondents as a whole did not agree with the unidimensionality feature of the CETSCALE. Practical implications – The results of the study show that Bangladeshi consumers prefer to see “Made in Bangladesh” tags when buying consumer products – a significant potential threat that the multinational companies need to address while planning to expand business in Bangladesh. Originality/value – This type of rigorous study on Bangladesh has never been done before. Moreover, the study identifies the difference in ethnocentric behavior of the consumers living in border and non-border areas – a study of ethnocentrism from a different point of view.


2010 ◽  
Vol 40 (4) ◽  
pp. 815-829 ◽  
Author(s):  
Sheldon Bacon ◽  
Peter M. Saunders

Abstract An analysis is made of data from 30 Aanderaa recording current meters (RCMs) set on nine moorings located east of Cape Farewell, the southern tip of Greenland. The purpose of the measurements was to allow for the estimation of transport in the deep western boundary current (DWBC) below a depth of about 1500 m. The records commenced in September 2005 and lasted from 9.5 to 11.5 months. After calibration of the raw data, 12-h averages of temperature and current were derived and the latter employed to estimate the flow across and along the array direction. The 9.5-month average transport of water colder than 3°C was found to be 7.8 Sv (1 Sv ≡ 1 × 106 m3 s−1) with a standard error of 0.8 Sv. For water denser than σθ = 27.85 kg m−3, the transport is calculated as 4.5 Sv. Whether either of these values is significantly different from comparable measurements made 500 km upstream cannot be determined. In marked contrast, for σθ > 27.8 kg m−3, the transport is estimated as only 9.0 Sv, smaller than the widely accepted value of 13 Sv for nearby measurements made in 1978. A reevaluation of the calculations and assumptions made then allows one to determine the uncertainty of the earlier estimate and thereby conclude that the difference between the previous and present measurements is significant, that is, that the transport has decreased between 1978 and 2005–06. A weakening of the transport during the 9.5-month period is also observed, along with a warming and an increase in salinity in the core of the DWBC. These latter changes are shown to be consistent with interannual variability rather than a long-term trend.


1880 ◽  
Vol 30 (200-205) ◽  
pp. 520-533

During the last three years I have been greatly occupied with observing and counting musical beats, for the purpose of discovering the cause and amount of error in Appunn’s reed tonometer, and of measuring the number of vibrations made in a second by tuning-forks and organs, as materials for my “ History of Musical Pitch.” The following are brief notes of some of the observations then made :— When two musical notes nearly but not accurately form a consonance, or are in unison, they beat. Under ordinary circumstances the number of beats in a second of a disturbed unison is equal to the difference of the number of double vibrations in a second made by each note. It is not so always, as will be shown later on. If x and y be the “ pitch ” or number of vibrations in a second, made by two musical tones, of which y is the sharper ; then, if my — nx =0, the tones form what I have termed a considence , that is, the n th partial of x falls on the same rank or seat as the m th partial of y . Considences are not always consonances, because other partials of the notes may beat roughly, as when m : n = 8 : 9 or 9 :10 or 15 :16, which are well known dissonances, but give appreciable considences. But if the pitch of either x or y be slightly altered, so that my — nx =± b , the two consident partials become what I have termed dissident , or placed on different ranks or seats, and b beats in a second are heard, being called “ sharp” when positive, that is when my > nx , and “ flat ” when negative, that is when my < nx . This includes the unison for which m = n . Hence all beats heard are beats of simple partial tones , however compound may be the tones which contain them. This agrees thoroughly with my observations. Tuning-forks are comparatively simple but always possess an audible second partial or octave, and sometimes higher partials still, capable of being so reinforced by resonance jars properly tuned to them, that beats can be separately obtained from them and counted. This is a matter of great importance in the construction of a tuning-fork tonometer. When the tone is very compound, as in the case of bass reeds (especially those of Appunn’s tonometer, furnished with a bellows giving, when properly managed, a perfectly steady blast for an indefinite length of time), beats can be obtained and counted from the 20th to the 30th and even the 40th partial, without any reinforce­ment by a resonance jar.


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