scholarly journals Large Element Count Flag

2020 ◽  
Author(s):  
Keyword(s):  
2009 ◽  
Vol 322 (3) ◽  
pp. 802-832 ◽  
Author(s):  
William M. Kantor ◽  
Ákos Seress

1968 ◽  
Vol 1 (3) ◽  
pp. 156-156
Keyword(s):  
The Dead ◽  

SINCE this paper was submitted for publication a further case relevant to the issue of the sentencing of youthful manslaughter has been reported (R. v. Turrise; Sydney Morning Herald 4.7.1968). In brief, the youth, aged 17 years, was charged with the murder by shooting of his 24-year-old brother. T. had his plea of guilty to manslaughter accepted by the Crown. The evidence indicated that the accused was of good character, and that he had bought a .22 repeating rifle to protect himself from his brother who was a “violent hoodlum who was released from prison a week before his death”. Mr. Justice Allen is reported as saying that “It was tragic to see a schoolboy charged with the murder of his brother”. He said that “in his view the Crown's acceptance of the manslaughter plea was completely appropriate because there was undoubtedly a large element of provocation”. He continued, “the dead man had been described as a hoodlum, a man of violence and probably a psychopath”. Mr. Justice Allen sentenced T. to 3 years gaol, but suspended execution of the sentence on his entering a $500 bond for three years.


1992 ◽  
Vol 6 ◽  
pp. 291-291
Author(s):  
Roger D. K. Thomas ◽  
Wolf-Ernst Reif

Organic design arises, on every scale, by the spontaneous self-organization of successively more complex structures from simpler subsidiary components. The resulting structures converge repeatedly on architectural designs that can be constructed by growing organisms, and that are viable but not necessarily optimal in relation to any one function. Empirical observations and theoretical models of developmental processes suggest that these recurrent elements of design are fixed point attractors which organic dissipative structures must necessarily approach. We characterize these structures as topological attractors, thereby emphasizing that they are determined by the properties of matter and the geometry of space-time.We have derived a set of potential designs for the elements of animal skeletons, in terms of geometric rules, growth processes, and the properties of materials. Skeletons or components of the skeletons of actual living and extinct organisms are matched with the possibilities defined within this theoretical morphospace. The extent to which the skeletal components of individual organisms are differentiated, exploiting various parts of the skeleton space, provides a crude metric of structural complexity. The skeleton space serves as a common context, in which we can compare the extent and pattern of exploitation of this range of potential organic designs, from one taxon to another.Our analyses show that the most evolutionarily advanced animals in a given class or phylum generally do not have the most complex skeletons; that molluscs and vertebrates are more morphologically diverse than arthropods; and that the physical constraints of life on land and in the air substantially limit the variety of skeletal structures suitable to be employed by animals living in these environments. Moreover, when the skeletons of all known animals, living and extinct, are considered together, we find that the total range of possible skeletal designs has been very fully exploited.These results strongly support the hypothesis that the essential elements of organic design are inherent in and predictable from the material properties of the universe. Environmental and demographic circumstances, invariably involving a large element of chance, together with the constraints of phylogenetic history largely determine the course of evolution in individual lineages. In contrast, structural principles such as those delineated here determine the recurrent themes of organic design, over large numbers of taxa and long periods of time. Thus, it is no accident that two major groups of animals that have most successfully exploited jointed lever skeletons, vertebrates and arthropods, have achieved the most diversified adaptive radiations, in the sea, on land and in the air.Among the structural paradigms defined within the skeleton space, stronger and weaker topological attractors may be identified empirically by the frequencies with which particular design elements have evolved independently, in unrelated taxa. Plausible functional or constructional rationales can readily be devised, ex post facto, to explain the repeated convergence of organic structures on some obvious strong topological attractors, such as branching networks, spiral cones, and bivalved shells. Unfortunately, it seems unlikely that an analytical method can be devised to predict these strong attractors a priori, as the variables involved cannot all be quantified in the same way.


Author(s):  
Benoit Stalin ◽  
Dongyang Yang ◽  
Yong Xia ◽  
Qing Zhou

This article investigates the influence of finite element model features on Fiber Reinforced Polymer (FRP) crushing simulation results. The study focuses on two composite material tube models using single shell modeling approach. The chosen material model is MAT58 (*MAT_LAMINATED_COMPOSITE_FABRIC) from the commercial finite element analysis software LS-Dyna. The baseline models geometry and material parameters come from a model calibration conducted for lightweight vehicle investigation. Five parameters are investigated. The mesh size and the number of integration point (NIP) are generic and ERODS, TSIZE and SOFT are the non-physical parameters of MAT58. This analysis aims at discuss the influence of these parameters on the simulation results focusing on the initial force peak and the average crush load, regarding results realism and instabilities such as large elements deformation and abnormal peak values. Also, the impact of the number of CPUs involved in the simulation calculation is presented. Recommendations are given to set the mesh size and the NIP. TSIZE value should be selected regarding the simulation time step. On the other hand, ERODS has to be adjusted manually. Both are determinant for simulation robustness. Further studies are proposed to find out the reasons of large element deformation.


Author(s):  
Linda Hargreaves ◽  
Julia Flutter

Internationally, the status of teachers is fraught with ambiguity, contradiction, and complexity. Status, simply defined as one’s “standing in society,” has undergone many redefinitions as lives and societies have become more nuanced and complex. Status, historically ascribed through inheritance and wealth, has been largely replaced by status achieved through individual effort, study, and achievement. The medical, legal, and clerical professions have traditionally enjoyed high status for their specialist qualifications and social responsibility, although the correlation between academic success and the comfortable family socioeconomic circumstances in which many aspiring to these professions also lends them a large element of ascribed status. Teachers experience a status paradox. For many, teaching has been a route out of the working class toward a more professional status. Teachers, in many countries but not universally, are highly trained, well qualified, dedicated, and trusted in their communities. Relative to the medical profession, however, teachers are poorly paid, and experience poor working conditions, limited professional autonomy, and high accountability. Their participation in trade union activities prompts debate as to whether teaching should be classed as a “profession.” Yet, despite the 1966 UNESCO and the International Labour Organization’s strong recommendation that teaching should be recognized as a profession and accorded high status, it remains at best a semiprofessional occupation. There is great variation across the globe in public respect and government treatment of teachers. International comparative surveys lack overall consensus but suggest that teachers in Taiwan, major Chinese cities, and Finland enjoy high status as compared with those in Brazil, Israel, and Italy, for example. Classic theories of status include those of Karl Marx and Max Weber. For Marx it is determined by socioeconomic status, but for Weber cultural and social affiliations can outweigh economic factors. Teaching straddles the two. Twentieth-century theorists, such as Talcott Parsons in the United States, have linked status to educational achievement. Pierre Bourdieu relates status to social reproduction of social class-related “habitus” in taste and consumption and Anthony Giddens to individual lifestyle choices not necessarily related to status. Recent research in England supports Weber’s cultural determinants, but international surveys reveal complex and debatable relationships between pay, student performance, and status. High percentages of the public think teachers deserve higher salaries that are linked to performance. Teaching as a lifestyle choice still appears to be motivated at least as much by intrinsic, “psychic” rewards as by well as extrinsic ones. Teachers rate their own status lower than do those who work with them. A recent international survey of teachers found over two-thirds in general, and over 95% in Sweden, France, and the Slovak Republic, thought teaching was not valued in society. The portrayal of teachers in the media may be relevant here. While this has become more positive in tone and prominence in England since the 1990s, there are wide cultural differences internationally. Improving teacher status is a complex challenge. Potential contributory factors include higher entry standards and competition to join; the creation of professional associations, as opposed to unions; improved and safe conditions of work; higher pay linked to performance; professional autonomy and involvement in decision-making; and teachers themselves rating their status more highly. The UNESCO Global Sustainable Development Goals for Education 2030 provide a set of overarching aims for the future of teacher status, envisaging teachers not as adults in a child’s world, but as orchestrators of national sustainable development.


1989 ◽  
Vol 3 (6) ◽  
pp. 509-525 ◽  
Author(s):  
Gislin Dagnlie ◽  
Henk Spekreijse ◽  
Bob van Dijk

AbstractUsing small checkerboard stimulus fields, we have recorded visually evoked potentials (VEPs) in an alert rhesus monkey from an array of 35 electrodes chronically implanted between dura and arachnoid to study mass neuronal activity in striate and peristriate visual cortex. Although the principal purpose of this work was to study in detail cortical mapping in this particular animal for future intracortical recordings, we report here the usefulness of our approach for the non-invasive study of cortical processing, in particular of cortical magnification and receptive-field properties over the central 6° of the visual field.The striate and extrastriate components in the pattern onset VEP both have a double negative-going waveform, with N–P–N peak latencies of 75–100–135 ms and 90–115–160 ms, respectively, for small element sizes and moderate contrasts; latencies may be 5 ms shorter for large element sizes and high contrast. We found little activity at electrode locations over visual areas beyond V2. The waveforms and timing permit some careful speculation concerning intracortical processing and VEP generation.The complex logarithmic form of the retinotopical projection provides a satisfactory model for our data, if a value of 1–1.2° is used for the offset parameter a. Our data suggest that the most abundant receptive-field size in foveal striate cortex has a center diameter of 12′. This size remains constant up to 2° eccentricity, and increases only slowly up to 4°. The smallest receptive-field sizes seem to be independent of eccentricity, throughout the central 4° of Vl, with a value of 4–8′, in agreement with single-cell data reported by Dow et al. (1981) and Van Essen et al. (1984).


Geophysics ◽  
1988 ◽  
Vol 53 (5) ◽  
pp. 650-658 ◽  
Author(s):  
Richard E. Duren

General mathematical expressions for a marine source array’s (1) far‐field pulse spectrum, (2) radiated energy density, and (3) directivity are developed for both a source in an infinite homogeneous medium and a source operating near the ocean surface. These results, intended to assist the analysis and design of marine source arrays, apply to any marine source array when (1) individual elements radiate isotropically, (2) their individual waveforms are specified, and (3) the array geometry is specified. Arbitrary geometry and arbitrary isotropic waveforms are allowed. The theory assumes linear superposition of the individually specified waveforms, and is consistent with the “square law effect” for identical elements. For an array of small elements, expended energy agrees with the array’s radiated energy found using far‐field methods. Also, the energy radiated from an array with large element spacing is equal to the sum of the independently radiated energies. Two closely spaced identical elements radiate four times the energy contained in a single outgoing waveform over all space. The appropriate directivity definition for marine seismic sources is the ratio of the radiated energy density per unit solid angle in a particular direction to the average radiated energy density per unit solid angle. This definition allows directivity to be expressed explicitly in terms of the individual frequency spectra and geometry.


2000 ◽  
Vol 123 (4) ◽  
pp. 606-613 ◽  
Author(s):  
Ahmed A. Shabana ◽  
Refaat Y. Yakoub

The description of a beam element by only the displacement of its centerline leads to some difficulties in the representation of the torsion and shear effects. For instance such a representation does not capture the rotation of the beam as a rigid body about its own axis. This problem was circumvented in the literature by using a local coordinate system in the incremental finite element method or by using the multibody floating frame of reference formulation. The use of such a local element coordinate system leads to a highly nonlinear expression for the inertia forces as the result of the large element rotation. In this investigation, an absolute nodal coordinate formulation is presented for the large rotation and deformation analysis of three dimensional beam elements. This formulation leads to a constant mass matrix, and as a result, the vectors of the centrifugal and Coriolis forces are identically equal to zero. The formulation presented in this paper takes into account the effect of rotary inertia, torsion and shear, and ensures continuity of the slopes as well as the rotation of the beam cross section at the nodal points. Using the proposed formulation curved beams can be systematically modeled.


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