scholarly journals FUNCTIONAL PEARL Unfolding pointer algorithms

2001 ◽  
Vol 11 (3) ◽  
pp. 347-358 ◽  
Author(s):  
RICHARD S. BIRD
Keyword(s):  
Formal Verification ◽  
Type Theory ◽  
Algebraic Approach ◽  
Functional Approach ◽  
Data Refinement ◽  
New Ideas ◽  
The Subject ◽  
Pointer Aliasing

A fair amount has been written on the subject of reasoning about pointer algorithms. There was a peak about 1980 when everyone seemed to be tackling the formal verification of the Schorr–Waite marking algorithm, including Gries (1979, Morris (1982) and Topor (1979). Bornat (2000) writes: “The Schorr–Waite algorithm is the first mountain that any formalism for pointer aliasing should climb”. Then it went more or less quiet for a while, but in the last few years there has been a resurgence of interest, driven by new ideas in relational algebras (Möeller, 1993), in data refinement Butler (1999), in type theory (Hofmann, 2000; Walker and Morrisett, 2000), in novel kinds of assertion (Reynolds, 2000), and by the demands of mechanised reasoning (Bornat, 2000). Most approaches end up being based in the Floyd–Dijkstra–Hoare tradition with loops and invariant assertions. To be sure, when dealing with any recursively-defined linked structure some declarative notation has to be brought in to specify the problem, but no one to my knowledge has advocated a purely functional approach throughout. Mason (1988) comes close, but his Lisp expressions can be very impure. Möller (1999) also exploits an algebraic approach, and the structure of his paper has much in common with what follows.This pearl explores the possibility of a simple functional approach to pointer manipulation algorithms.

scholarly journals Macroeconomic Modelling at the Institute: Hopes, Challenges and a Lasting Contribution

2018 ◽  
Vol 246 ◽  
pp. R3-R14 ◽  
Author(s):  
Ray Barrell ◽  
Andy Blake ◽  
Garry Young
Keyword(s):  
Global Economy ◽  
Early Years ◽  
Macroeconomic Models ◽  
Macroeconomic Modelling ◽  
New Frontier ◽  
New Ideas ◽  
The Subject ◽  
The Uk ◽  
Economic Forecasts ◽  
Modelling And Forecasting

The Institute is a world leader in macroeconomic modelling and forecasting. It has produced quarterly economic forecasts for around sixty years, supported by macroeconomic models. The aim of the original builders of macroeconomic models was to transform understanding of how economies worked and use that knowledge to improve economic policy. In the early years, when computers were rare, macroeconomic modelling was a new frontier and Institute economists were among the first to produce a working model of the UK economy. It is remarkable how quickly models were being used to produce forecasts, assess policy and influence the international macroeconomic research agenda. The models built at the Institute were mainstream in the sense that they followed the contents of standard macroeconomic textbooks, developed with the subject, and fitted the facts as they were known at the time. There were continual improvements in understanding as the subject developed in response to new ideas and developments in the global economy. This article celebrates the development of macroeconomic modelling at the Institute and the contribution it has made to public life.

“Systems”, Strengths, Weaknesses and Challenges

2017 ◽  
Vol 4 (1) ◽  
pp. 49-59
Author(s):  
Frank Stowell
Keyword(s):  
Action Research ◽  
Systems Thinking ◽  
Research Funding ◽  
Cumulative Effect ◽  
Research Programme ◽  
Common Reason ◽  
New Ideas ◽  
The Subject ◽  
The University

Systems and Cybernetics no longer occupies the position, in academic circles, it once did. There are many reasons why this is the case but a common reason given is the lack of research funding for the subject. The knock-on effect is that the subject has fewer 'champions' and as a consequence is less prominent then it once was. There are many factors that mitigate against research funding for the domain but the cumulative effect is that there are few (if any) new ideas generated now which in turn is having an impact upon the number of academics attracted to it. In this paper the author revisits the action research programme at the University of Lancaster. This project contributed valuable insights into organisational inquiry and the nature of Systems thinking for over 30 years. In this paper the author revisits the programme to discover if there are lessons to be learnt that may be adopted to help provide a means of re-establishing the profile of the domain.

On Looking Backwards

1980 ◽  
Vol 15 (3-4) ◽  
pp. 389-404
Author(s):  
Julius Gould
Keyword(s):  
The Moon ◽  
Scientific Approach ◽  
New Ideas ◽  
The Subject ◽  
Political Structures

THE LAST FIFTEEN YEARS HAVE PASSED WITH SURPRISING speed. They have certainly fulfilled the imperatives of the curse: ‘may you live in interesting times!’. Too much has happened in too many places – on the moon as well as on earth. New movements, new ideas, new cults have emerged. Populations have multiplied and so have inventions. New centres of learning have been established and old ones have been subverted, not least by an overdose of political zeal. The sciences of man have developed – more painfully than was hoped and with fewer concrete results than was (and is) desired. I think we have learned that our efforts to understand complex social and political structures (including those constituted by governments and oppositions) may themselves founder (or flounder) in complexities. Some of those complexities are endemic to the subject of our study; others are the result of our own confusion of categories or of premature conceptualization; others result from overspecialization – and others from the hazards of cross-disciplinary study. Perhaps the cardinal error has been to seek too much – and expect too much – from a narrowly ‘scientific’ approach. We all know of cases on the heads of which one or other of these caps can fit.

scholarly journals Towards the Creative-Oriented University

2020 ◽  
Vol 2 (1-2) ◽  
pp. 07-14
Author(s):  
Mehdi Tajpour ◽  
Elahe Hosseini
Keyword(s):  
Cost Benefit Analysis ◽  
Regional Scale ◽  
Cost Benefit ◽  
Benefit Analysis ◽  
Entrepreneurial Universities ◽  
Informal Networks ◽  
New Ideas ◽  
The Subject ◽  
Progressive Organizations ◽  
Entrepreneurial Capital

Entrepreneurial universities are the center of progressive organizations that have reconsidered themselves in order to adapt to complex environmental conditions. Thus, the purpose of this study is to investigate the towards the creative-oriented university. In this research, which has used descriptive methods, in order to understand the concepts of towards the creative-oriented university, the background of the subject has been studied in the form of library and documentary studies. Thus,conclusion show that the effect of entrepreneurial universities on a regional scale extends far beyond commercial outputs while a simple cost-benefit analysis can provide indirect and tangible results in terms of human capital attraction, entrepreneurial capital formation, informal networks, new ideas, and so on.

scholarly journals The straggling of β-particles

1929 ◽  
Vol 125 (798) ◽  
pp. 420-445 ◽  
Keyword(s):  
Classical Theory ◽  
Experimental Investigations ◽  
Theoretical Treatment ◽  
A Value ◽  
Thin Foils ◽  
New Ideas ◽  
The Subject ◽  
The Individual ◽  
Individual Particles ◽  
Α Particles

When a beam of electric particles is passed through a sheet of matter the energy of the individual particles is reduced. The loss of energy is not the same for all the particles so that particles incident on the foil with the same energy emerge with different energies. This dispersion of the energy caused by the foil is known as the "straggling" of the particles. The straggling of α-particles has been the subject of several experimental investigations, and the theory in this case was adequately developed by Bohr in 1915. In the case of β-particles, however, the straggling was not experimentally investigated until quite recently and no theoretical treatment of the phenomenon has been given, the calculations of Bohr being, as he showed, applicable only to α-particles. The purpose of the work described in this paper is to develop a theory of the straggling of β-particles by thin foils and by means of it to interpret the results of experiment. The paper is arranged as follows. In 2 an account is given of the state of the experimental work on the subject, and in particular the effect of the complications introduced by "scattering" are considered. The formula derived by Bohr for the straggling of electric particles is given in 3 and its inapplicability to β-particles demonstrated. The present calculations of the straggling of β-particles are given in 4. The theory of the straggling of electric particles resolves itself into two parts. The first deals with the dynamics of collisions between electric particles and atoms, and is the same whether we are concerned with the straggling or some other phenomena such as ionisation of "stopping power." This may be called the fundamental theory and its requirements may be summarised in the function ϕ (Q) which express the frequency of collisions in which the electric particle loses energy of amount Q. The second part of the theory is the process of calculating the straggling by means of probability theory from the function ϕ . This may be regarded as the straggling theory proper and it is the main subject of 4. When the present calculations were started it was intended to calculate the straggling on the basis of classical theory only, the value of the function ϕ on this theory being definitely known. However, after some practice with the type of calculation involved it was decided to calculate the straggling for other forms of ϕ . From the results obtained it is possible to deduce the straggling corresponding to any form which ϕ may reasonably have, and if a new theory leads to a value of ϕ different from the classical value, the straggling on the new theory may readily be determined. Alternatively this fuller treatment may be used for the reverse process of calculating from the observed straggling the value of ϕ to which it corresponds. This is considered to be the most convenient procedure and in 5 the form of ϕ which explains the experimental results is deduced. this is compared in 6 with the value of ϕ on classical theory. A brief outline is given in 7 of certain new ideas concerning the nature of collisions of electric particles with electrons and atoms.

Propeller and Vane Wheel

1980 ◽  
Vol 24 (04) ◽  
pp. 203-226 ◽  
Author(s):  
Otto Grim
Keyword(s):  
Young People ◽  
The United States ◽  
German Society ◽  
Memorial Lecture ◽  
Naval Architecture ◽  
Great Pleasure ◽  
New Ideas ◽  
The Subject ◽  
First Time ◽  
To Receive

The vane wheel is a freely rotating device installed on the propeller shaft behind the propeller to provide additional thrust at no increase in power. The wheel, which is larger in diameter than its companion propeller, functions as a turbine by using the otherwise-wasted propeller slipstream to generate the extra thrust. This paper describes a series of tests performed at the Hamburg Ship Model Tank to compare the efficiency of the vane wheel arrangement with other propulsion units, including a conventional propeller, contrarotating propeller, and propeller with fixed guide mechanism. The Appendix provides a mathematical analysis of the performance of the various units investigated. Preface: For many years I had the great pleasure to live near Georg Weinblum, to work with him, and to receive his advice. After he retired I became his successor at Hamburg University. In 1938 I had met Georg Weinblum for the first time; in 1952 — after his return from the United States — for the second time, and after that we met regularly. He encouraged me to write my thesis and to work as a scientist. He always took a great interest in promoting young people and in awakening their enthusiasm for science. Many young people have had this experience and think of him with gratitude. Due to the founders' intentions, the memorial lecture should deal with a subject which belongs to naval architecture and which serves its development. I have chosen the subject, Propeller and Vane Wheel, which I presented for the first time to the German Society of Naval Architecture (Schiffbautechnische Gesellschaft) in 1966. I take this opportunity to discuss the subject again, and to a different extent, because I believe that the purpose of this work is really important and can be achieved without any difficulty in the present situation, where the search for new ideas with regard to the saving of energy has become an urgent necessity.

Lyuben Georgiev’s innovative ideas concerning Bulgarian language teaching Radomira Videva. Easy-to-read legal texts as a means of INCREASING the cognitive accessibility of legal language

Proglas ◽  
2021 ◽  
Vol 30 (2) ◽  
Author(s):  
Ivan Cholakov ◽  
Keyword(s):  
High Schools ◽  
Language Learning ◽  
Mother Tongue ◽  
Language Teaching ◽  
Junior High Schools ◽  
Legal Texts ◽  
New Ideas ◽  
The Subject ◽  
Cognitive Accessibility ◽  
Important Evidence

The present paper is focused on Lyuben Georgiev’s innovative ideas concerning Bulgarian language teaching. The author’s new ideas presented in his work The Mother Tongue in Our Junior High Schools and High Schools (a Language Teaching Endeavour) (1933) have not been the subject of scientific research so far. L. Georgiev’s set of didactic ideas is important evidence for the overcoming of the Herbartian model and the orientation of language teaching towards the formation of communicative competencies. Emphasizing the creative nature of pedagogical interaction, Lyuben Georgiev offers a comprehensive system of ideas – a system that is in line with modern trends in language learning.

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