Showing papers by "University of Newcastle published in 1971"
TL;DR: In this paper, conditions for Kalman-Bucy filters were found guaranteeing asymptotic stability, but not necessarily uniform stability, with respect to complete controllability conditions.
Abstract: Conditions are found guaranteeing asymptotic stability, but not necessarily uniform asymptotic stability, of Kalman-Bucy filters. Relaxation of a uniform complete controllability condition proves the key to generating the results.
95 citations
TL;DR: In this article, a new approach to the optimization of the linear, possibly time-varying, system [email protected] = Fx + Gu |u"i| @? 1 with respect to the performance index V = @!^t^"^1"t"""0x'Qxdt.
55 citations
TL;DR: For any prime power n there are two non-isomorphic design graphs with v = 2 (n+2), k = n(n+l) and X = n.
Abstract: Suppose there exist a 'balanced incomplete block design with X = 1 and an affine resolvable balanced incomplete block design, the two designs having the same replication number. Combining these designs we construct two strongly regular graphs. This is applied to give a new family of design graphs ((y, k, X)-graphs). Finally, we show that for any prime power n there are two non-isomorphic design graphs with v = « 2 (n+2) , k = n(n+l) and X = n .
45 citations
TL;DR: The main result proved is that the smoother is unstable when the usual set of conditions hold which guarantee asymptotic stability of the optimum filter.
Abstract: The stability of fixed-lag smoothers for linear system state estimation is considered. The main result proved is that the smoother is unstable when the usual set of conditions hold which guarantee asymptotic stability of the optimum filter.
44 citations
40 citations
TL;DR: In this paper, the optimal fixed-lag smoother is studied, and viewed as a finite-dimensional linear system, and the complexity of the smoother can be quantitatively examined, and design criteria suggested for the choice of lag interval.
35 citations
TL;DR: In this paper, electron emission from anodically oxidised aluminium was investigated in the pressure range 10−5 Torr to 10−9 Torr and two essentially different types of emission were observed.
34 citations
TL;DR: Very slow rates of uptake were observed with intact organisms but protoplast preparations assimilated the nucleic acid precursors much more readily.
Abstract: The entry of both nucleotides and base precursors into whole cells and the nucleic acid fraction of the blue-green alga Anacystis nidulans has been examined. Very slow rates of uptake were observed with intact organisms but protoplast preparations assimilated the nucleic acid precursors much more readily.
31 citations
TL;DR: In this article, the daily faecal and urinary production from individual pigs were measured over the live-weight range 20-90 kg, and three different feeding regimes were employed, and the results from the study on individual pigs are, in general, confirmed by the trial carried out on groups of pigs.
29 citations
01 Jan 1971-Metallurgical and Materials Transactions B-process Metallurgy and Materials Processing Science
TL;DR: In this paper, an investigation of thermomigration in interstitial solid solutions of carbon in β-Ti, V, α-Fe, Co, Ni, and Pd has been carried out using a radioactive tracer technique.
Abstract: An investigation of thermomigration in interstitial solid solutions of carbon in β-Ti, V, α-Fe, Co, Ni, and Pd has been carried out using a radioactive tracer technique. A substantial solute redistribution occurred towards the hotter regions in α-iron and vanadium and towards the colder regions in palladium whilst for Co, Ni and β-Ti very little segregation was observed. The measured heats of transport were (in kcal per g-atom): α-Fe, −14.1±1.5; V, −4.9±1.0; Pd, +8.4±1.5; Co, +1.5±1.5; Ni, −1.6±1.4; β-Ti, −1.0±1.0. An examination of the results obtained together with all of the published data for interstitial solute thermomigration suggests that electronic effects could be of major importance in determining the redistributions observed.
25 citations
TL;DR: Reflectivities of vitrinites (Carbon 83·1, 88·6 and 93·3%) carbonized at 450, 600 and 750°C have been measured at a number of wavelengths between 403 and 709 run and refractive and absorptive indices derived for the samples using Beer's relationship as discussed by the authors.
Abstract: The purpose of this paper is to show that the various differentiability conditions for the norm of a normed linear space can be characterised by continuity conditions for a certain mapping from the space into its dual. Differentiability properties of the norm are often more easily handled using this characterisation and to demonstrate this we give somewhat more direct proofs of the reflexivity of a Banach space whose dual norm is strongly differentiable, and the duality of uniform rotundity and uniform strong differentiability of the norm for a Banach space.
TL;DR: In this article, the classical problem of parameter selection of three-term controllers within the framework of suboptimal linear regulator theory is viewed, and iterative techniques are used to determine the controller parameters so that the expected value of a quadratic loss type performance index is minimized, with the initial states of the system a random variable uniformly distributed over a unit sphere.
Abstract: The classical problem of parameter selection of three-term controllers within the framework of suboptimal linear regulator theory is viewed. Iterative techniques are used to determine the controller parameters so that the expected value of a quadratic loss type performance index is minimized, with the initial states of the system a random variable uniformly distributed over a unit sphere.
TL;DR: The interference effects observed in series of absorption studies using nitrous oxide/acetylene or air/ acetylene flames are interpreted in terms of the nature of the chemical species present in solution, and elements studied include Nb, Ta, Ti, Y, V, W and Ni.
TL;DR: In this article, nine mathematics tests were devised on lines suggested by the Piagetian model and one hundred and one girls, chosen from three schools (primary, junior secondary and senior secondary), were tested on items which varied on two dimensions, viz., the abstractness of the elements operated upon and the interrelationships of the operations in the item which defined its structure.
Abstract: Nine mathematics tests were devised on lines suggested by the Piagetian model. One hundred and one girls, chosen from three schools (primary, junior secondary and senior secondary), were tested on items which varied on two dimensions, viz., the abstractness of the elements operated upon and the interrelationships of the operations in the item which defined its structure. As predicted, items with both concrete elements and structure were successfully handled by all age groups; as either structures or elements were made more abstract the younger age groups began to fail and only the oldest group had any success when both structures and elements were made more abstract. Implications were seen in the study which would be of interest to psychologists working with the Piagetian model as well as to teachers and curriculum planners.
TL;DR: In this article, the mean square errors of Pf and Ps were compared with the linear least squares filtered and smoothed estimates of a stationary process of spectral density S(ω) in white noise with spectral density No.
Abstract: Comparison is made between the mean-square errors Pf and Ps associated with the linear least-squares filtered and smoothed estimates of a stationary process of spectral density S(ω) in white noise of spectral density No. A universal curve is obtained which relates the minimum possible value of Ps/Pf to ωmax{S(ω) No}. The curve sets a bound on the maximum improvement over filtering which smoothing will offer, in terms of the maximum signal/noise ratio.
TL;DR: In this paper, the authors define ann-type (1, −1) matrix N = I + R of ordern ≡ 2 (mod 4) to haveR symmetric andR2 = (n − 1)In.
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01 Jan 1971-International Journal of Human-computer Studies \/ International Journal of Man-machine Studies
TL;DR: A general theory of form, based on geometric probabilities, is presented, which leads to the design of a two-dimensional, retinal type computer which can be readily programmed to exhibit elementary, but fundamental, aspects of form perception.
Abstract: A general theory of form, based on geometric probabilities, is presented. The theory solves the problem of perceiving, detecting and extracting “interesting” visual shapes from an “uninteresting” background. The criteria for “interesting” shapes are not subjective ones, but appear to be fundamental objective criteria upon which a general analytic theory of form can be based. The theory leads to the design of a two-dimensional, retinal type computer which can be readily programmed to exhibit elementary, but fundamental, aspects of form perception. The computer has obvious applications in the field of pattern recognition. A pattern function theory is advanced to explain the αrhythm of natural automata. An example of a cybernetic control system, based on pattern function theory, is also presented.
TL;DR: In this article, it was shown that there is one particular model yielding the smallest error-variance in a sense to be described, and that this model is causally invertible.
TL;DR: In this paper, the solubilities of hydrogen and deuterium in Pd−Ag alloys containing 10, 20, 30 and 40 wt. % Ag were measured at 125°C by the Sieverts' technique using Pd black as the transference catalyst.
TL;DR: Linamarin and lotaustralin were isolated as a mixture from Trifolium repens L. and used as substrate for the assay of linamarase as discussed by the authors.
TL;DR: In this paper, an analysis of contributors and contributions to three British sociological journals together with some information on the membership of the British Sociological Association (B.S.A.) and of the Association's Committee is presented.
Abstract: This article presents an analysis of contributors and contributions to three British sociological journals together with some information on the membership of the British Sociological Association (B.S.A.) and of the Association's Committee. The material gives, among other things, a picture of the pattern of research activity and serves to reveal something of the institutional complex in which sociology in Britain is rooted. It may be considered as a contribution to the sociology of sociology.̂ The three journals are the Sociological Review (Soc. Rev.), the British Journal of Sociology (B.J.S.), and Sociology, Official Journal of the British Sociological Association (Sociology). From 1908 to 1953 the Sociological Review was published first by the Sociological Society and then by the Institute of Sociology. The Institute ran into difficulties in the early fifties and the Review was taken over by Keele University^ which commenced publication of a 'New Series' in 1953 with an editorial board composed of seven professors from Keele University. The B.J.S. was founded in 1950 by the London School of Economics in conjunction with Routledge the publishing house; the editors were three professors from the School. Sociology was founded jointly by the B.S.A. and the Clarendon Press, a division of the Oxford University Press. It first appeared in 1967 with a professor from Bristol University as editor, and an editorial board consisting of a leaurer from Cambridge University, a professor from Newcastle University and a non-academic from Political and Economic Planning, a private research institute. Subsequent changes in editorial arrangements have been made in each case and a feature of Sociology is the frequent rotation both of the editorship and of membership of the editorial board. The Sociological Review had two\"̂ issues per annum, the B.J.S. four, and Sociology three. We have included in our analysis all issues of the B.J.S. and Sociology and all issues of the New Series of the Review, i.e. from 1953.
TL;DR: In this article, it was shown that 6-methyl, 6,6-dimethyl-, and 6-phenyl-6,7-dihydrodipyrido[1,2-a:2, 1 -c] dibro-mides are reversible one electron transfer systems with similar redox potentials to diquat dibromide.
TL;DR: In this paper, the lattice parameters, magnetic properties and cation distributions have been investigated, and the origin of a thermal hysteresis in the magnetization-temperature curves found close to the Curie point is discussed.
TL;DR: A construction for amicable Hadamard matrices is given, and are used to generalize a construction for skew-Hadamards matrices.
TL;DR: Wallis as discussed by the authors conjectured a configuration for every v, k and lambda satisfying lambda(v-l) = k(k-l), and k lambda is a square if v is even, x2 = (k lambda)y2+(-1)(v-1)/2lamdaZ2 has a solution in integers x,y and z not all zero for v odd.
Abstract: A (v, k, lambda) configuration is conjectured to exist for every v, k and lambda satisfying lambda(v-l) = k(k-l) and k lambda is a square if v is even, x2 = (k lambda)y2+(-1)(v-1)/2lamdaZ2 has a solution in integers x,y and z not all zero for v odd. Disciplines Physical Sciences and Mathematics Publication Details Jennifer Seberry Wallis, Some results on configurations, Journal of the Australian Mathematical Society, 12, (1971), 378-384. This journal article is available at Research Online: http://ro.uow.edu.au/infopapers/938 SOME RESULTS ON CONFIGURATIONS
TL;DR: In this article, it was shown that room squares of order 4n exist for alln > 1 except possibly forn = 707 mod 771 orn = 180227 mod 196611.
Abstract: It is shown that Room squares of order 4n exist for alln > 1 except possibly forn = 707 mod 771 orn = 180227 mod 196611.