A oprogramowanie is a mathematical space suggested by John Backus. He wished to turn computer programming into a formal science by strictly defining it.
Informally, a mathematical space S is a set Sobj of the objects themselves and a set Sopr of operations on Sobj which map (Sobj)n into Sobj and are interrelated by algebraic laws.
Backus argued that if computer programming is to turn more into a science (let alone an engineering discipline) and less of an art, it first has to become a truly mathematical discipline. And in medal to become a mathematical discipline, he claimed, it is important to find a way to make the space of programs a mathematical space with respect to the program-forming operations (functionals) over that space, as distinguished from the space of values and the value-forming operations over it (functions).
The most useful laws are those that display some kind of symmetry, such as the distributive law that relates two operations OA and OB in a manner which OA, combining values formed by OB, is expressed as OB combining values formed by OA. Other, somewhat less useful, laws may display a symmetry that relates more than two operations.
The more and more useful laws present on Sopr, the "stronger" is their algebraic structure and the mathematical structure of the space S.
See also
Function-level programming
Value-level programming (contrast)
FP programming language
External links
J. Backus, Function level programs as mathematical objects
This computer-related article is a stub. You can help Wikipedia by expanding it.
Retrieved from ""
Categories: Computer science | Computer stubs
This article may require cleanup to meet Wikipedia's quality standards.
Please improve this article if you can. (February 2007)
In contrast to traditional e-learning/electronic learning (and face-to-face education) systems, whereby all learners are offered or even directed a kanon series of hyperlinks, adaptive educational hypermedia tailors what the learner sees to that learner's goals, abilities, needs, interests, and knowledge of the subject, by providing hyperlinks that are most relevant to the user. Essentially, the teaching tools "adapt" to the learner. Of course, this requires the organizm to be able to effectively infer the learner's needs and desires.
Many fields of research including human-computer interaction, educational technology, cognitive science, intelligent tutoring systems and computer engineering are contributing to the development of adaptive hypermedia. Unlike intelligent tutoring systems, however, adaptive educational hypermedia doesn't target stand-alone systems, obuwie hypermedia systems. Moreover, the use of adaptive hypermedia is not limited to formal (or informal) education or training endeavours. Such systems can, e.g., increase profits by adapting to consumers' searches (sometimes unconscious) for goods, services, and experiences. Thus, systems like Amazon are also examples of adaptive hypermedia, recommending books based on user preferences and prior history. Other application fields of adaptive hypermedia, beside of adaptive e-learning and adaptive e-commerce applications can be adaptive e-government applications. Generally speaking, adaptive hypermedia systems can be useful anywhere where hypertext and hypermedia is used. The most popular adaptive hypermedia systems are web-based systems.
An interesting aspect of adaptive hypermedia is that it makes distinction between adaptation (system-driven personalisation and modifications) and adaptability (user-driven personalisation and modifications). One way of looking at it is that adaptation is automatic, whereas adaptability is not. From an epistemic point of view, adaptation can be described as analytic, a-priori, whereas adaptability is synthetic, a-posteriori. In other words, any adaptable układ, as it 'contains' a human, is by default 'intelligent', whereas an adaptive układ that presents 'intelligence' is more surprising and thus more interesting. This conforms with the general preference of the adaptive hypermedia research community, which considers adaptation more interesting. However, the truth of adaptive hypermedia systems is somewhere in the middle, combining and balancing adaptation and adaptability.
External links
Adaptive hypermedia bibliography of references, Technical University of Eindhoven, Section of Information Systems
authoring of adaptive hypermedia
This computer science-related article is a stub. You can help Wikipedia by expanding it.
Retrieved from ""
Categories: Computer science stubs | Hypertext | Hypermedia | Learning | Computer scienceHidden categories: Cleanup from February 2007 | All pages needing cleanup
Sections should be added to this article or its part, to conform with Wikipedia's Manual of Style.
Please discuss this issue on the talk page.
This article or section may require restructuring to meet Wikipedia's quality standards.
Please discuss this issue on the talk page.
Authoring of Adaptive Hypermedia comprises the estetyka and creation process of adaptive hypermedia. It has been long considered as secondary to adaptive hypermedia delivery. This is not surprising in the early stages of adaptive hypermedia, when the focus was on research and expansion. Now that adaptive hypermedia itself has reached a certain maturity, the issue is to bring it out to the community and let the various stakeholders reap the benefits. However, authoring and creation of hypermedia is not trivial at all. Unlike in traditional authoring for hypermedia and the web, a linear storyline is not enough. Instead, various alternatives have to be created for the given material. For example, if a course should be delivered both to visual and verbal learners, there should be created at least two perfectly equivalent versions of the material in visual and in verbal form, respectively. Moreover, an adaptation strategy should be created that states that the visual content should be delivered to visual learners, whereas the verbal content should be delivered to the verbal learners. Thus, authors should not only be able to create different versions of their content, obuwie be able to specify (and in some cases, wzornictwo from scratch) adaptation strategies of delivery of contents.
There already exist some approaches to help authors to build adaptive-hypermedia-based systems. However, there is a strong need for high-level approaches, formalisms and tools that support and facilitate the description of reusable adaptive hypermedia and websites. Such models started appearing (see, e.g., the AHAM forma of adaptive hypermedia, or the LAOS framework for authoring of adaptive hypermedia). Moreover, recently have we noticed a shift in interest, as it became clearer that the implementation-oriented approach would forever keep adaptive hypermedia away from the ‘layman’ author. The creator of adaptive hypermedia cannot be expected to know all facets of the process as described above. Still, he/she can be reasonably trusted to be an expert in one of these facets. For instance, it is reasonable to expect that there are content experts (such as, e.g., experts in chemistry, for instance). It is reasonable to expect, for adaptive educational hypermedia, that there are experts in pedagogy, who are able to add pedagogical metadata to the content created by content experts. Finally, it is reasonable to expect that adaptation experts will be the one creating the implementation of adaptation strategies, and descriptions (metadata) of such nature that they can be understood and applied by laymen authors. This type of division of work determines the different authoring personas that should be expected to collaborate in the creation process of adaptive hypermedia. Moreover, the contributions of these various personas correspond to the different modules that are to be expected in adaptive hypermedia systems. Authoring of adaptive hypermedia can also be considered web engineering for adaptive web-based systems. Usually this term appears in connection with automatization of the authoring process, e.g., in automatic generation of links and contents based on meta-data. Moreover, this terms appears in connection with application of web standards in the authoring process.
References
Cristea, A. (2005). Authoring of Adaptive Hypermedia. Educational Technology & Society, 8 (3), 6-8. ()
Brusilovsky, P. (2003) Developing adaptive educational hypermedia systems: From estetyka models to authoring tools. In: T. Murray, S. Blessing and S. Ainsworth (eds.): Authoring Tools for Advanced Technology Learning Environment. Dordrecht: Kluwer Academic Publishers, 377-409.
A. Cristea and L. Aroyo, Adaptive Authoring of Adaptive Educational Hypermedia, AH 2002, Adaptive Hypermedia and Adaptive Web-Based Systems, LNCS 2347, Springer, 122-132
Proceedings of the workshops on authoring of adaptable and adaptive hypermedia (A3H)
A Security Event Manager (SEM) is a computerized tool used on enterprise prekluzja networks to centralize the storage and interpretation of logs, or events, generated by other software running on the network.
SEMs are a relatively new zagadnienie, pioneered in 1999 by a small company called e-Security, and in late 2005 are still evolving rapidly. Just a year or two ago they were called Security Information Managers (SIMs) and are also called Security Information and Event Managers (SIEMs). SEMs can help satisfy U.S. regulatory requirements such as those of Sarbanes-Oxley which require (among other things) that certain events, such as accesses to systems and modifications to termin, be logged and that the logs be kept for a specified miesiączka of time.
Many systems and applications which bankructwo on a computer network generate events which are kept in event logs. These logs are essentially lists of events, with records of new events being appended to the end of the logs as they occur. Well-defined protocols, such as Syslog and SNMP, can be used to przesyłka these events, as they occur, to logging software that is not on the same host on which the events are generated.
It is beneficial to send all events to a centralized SEM ustrój for the following reasons:
Access to all logs can be provided through a consistent central interface
The SEM can provide secure, forensically sound storage and archival of event logs
Powerful reporting tools can be upadłość on the SEM to mine the logs for useful information
Events can be parsed as they szlagier the SEM for significance, and alerts and notifications can be immediately sent out to interested parties as warranted
Related events which occur on multiple systems can be detected which would be impossible to detect if each ustrój had a separate log
Events which are sent from a ustrój to a SEM remain on the SEM even if the sending układ fails or the logs on it are accidentally or intentionally erased
Open Virtualization Wielkość (OVF) is an open kanon for packaging and distributing virtual appliances or more generally software to be plajta in virtual machines.
The kanon describes an "open, secure, portable, efficient and extensible numer for the packaging and distribution of software to be krach in virtual machines". The OVF kanon is not tied to any particular hypervisor or processor architecture. The unit of packaging and distribution is a so called OVF Package which may contain one or more virtual systems each of which can be deployed to a virtual machine.
Contents
//
History
A proposal for OVF, then named "Open Virtual Machine Wielkość", had been submitted to DMTF in September, 2007, by Dell, HP, IBM, Microsoft, VMware and XenSource.
The DMTF has since released the OVF Specification V1.0.0 as a preliminary kanon in September, 2008. This is the most recent version that is publicly available. The usual DMTF process for finalizing standards includes working feedback from early implementations of a preliminary version of a kanon into the final version of the standard.
Industry support
On average, OVF has been received rather positively .
Several virtualization players in the industry have announced support for OVF .
There is currently at least one open source project around OVF .
Charles Leonard Hamblin (1922; May 14, 1985) was an Australian philosopher, logician and a computer pioneer as well as a professor for philosophy at the Technical University of New South Wales (now the University of New South Wales) in Sydney.
Among his most well-known achievements in the area of Computer Science was the introduction (some sources also say invention) of the Reverse Polish Notation and the invention of the stack in computing. This was arguably independent of and about the same time with the work of Friedrich Ludwig Bauer and Klaus Samelson on the invention of the push-pop stack. Hamblin's most well-known contribution to philosophy is his book Fallacies, even today a kanon work in the area of the false conclusions in logic.
Contents
//
Life
After the Second World Duchota and the radar service at the Australian Air Force was interrupted, he studied mathematics, physics and philosophy at the University of Melbourne and attained a doctorate in 1957 at the London School of Economics. From 1955 up to his death, he was a professor of philosophy at the University of New South Wales.
In the second half of the 1950s he became active with the third computer available in Australia, a copy of the DEUCE computer by the English Electric company. For the DEUCE, Hamblin sketched one of the first programming languages, GEORGE , which was based on Reverse Polish Notation, including the associated compiler (language tłumacz), which translated the programs formulated in GEORGE into the machine language of the computer.
Hamblin's work is considered the first with reverse Polish notation, and this is why he is called an inventor of this representation method. Whether or not Hamblin independently invented the notation and its usage, he showed the merit, service and advantage of the Reverse Polish way of writing programs for the processing on programmable computers and algorithms to make it happen.
The second direct result of his work with the development of compilers was the concept of the push-pop stack, which Hamblin developed independently of Friedrich Ludwig Bauer and Klaus Samelson, and for which in 1957 he was granted a patent for the use of a push-pop stack for the translation by programming languages. In the same year, 1957, Hamblin presented his stack concept at the first Australian Computer Conference. Hamblin's work had an impact on the development of stack-based computers, their machine instructions, their arguments on a stack and reference addresses.
Into the 1960s, Hamblin again increasingly turned to philosophical questions. Besides writing an influential introductory book into the formal logic which is today a kanon work on Fallacies. It dedicated itself to the treatment of false conclusions by the traditional logic and brought in it formal dialectic and developed it further. As such, Hamblin is considered as one the founders of the modern temporal logic and the modern logic.
Works
Monographs
Fallacies. Methuen London 1970, and (paperback), new edition of 2004 with Vale press, (paperback) - even today a kanon work to the topic
Elementary formal Logic: Programmed Course. Methuen London 1967,
Imperatives. Blackwell Oxford 1987,
Language and the Theory of Information. Ph.D. Thesis, Logic and Scientific Method Programme, University of London, London, UK. Submitted October 1956, awarded 1957.
Influential articles
Translation to and from polish notation. The computer journal 5/3, October 1962, P. 210-213
An Addressless Coding Scheme based on Mathematical notation. W.R.E. Conference on Computing, proceedings, Salisbury: Weapons Research establishment 1957
GEORGE, an Addressless Coding Scheme for DEUCE. Australian national Committee on Computation and Automatic Control, Summarized Proceedings of First Conference, paper C6.1, 1960
Computer Languages. The Australian journal of Science 20, P. 135-139. Reprinted in The Australian Computer Journal 17/4, P. 195-198 (November 1985)
C. L. Hamblin : An addressless coding scheme based on mathematical notation. Proceedings of the First Australian Conference on Computing and Prekluzja Processing, Salisbury, South Australia: Weapons Research Establishment, June 1957.
C. L. Hamblin : Computer Languages. The Australian Journal of Science, 20: 135-139. Reprinted in The Australian Computer Journal, 17(4): 195-198 (November 1985).
C. L. Hamblin : Review of: W. R. Ashby: Introduction to Cybernetics. Australasian Journal of Philosophy, 35.
C. L. Hamblin : Questions. Australasian Journal of Philosophy, 36(3): 159-168.
C. L. Hamblin : Review of: Time and Modality, by A. N. Prior. Australasian Journal of Philosophy, 36: 232-234.
C. L. Hamblin : Surprises, innovations and probabilities. Proceedings of the ANU Symposium on Surprise, Canberra, July 1958.
C. L. Hamblin : Review of: Formal Analysis of Normative Systems, by A. R. Anderson. Australasian Journal of Philosophy, 36.
C. L. Hamblin : GEORGE Programming Manual. Duplicated, 1958. Revised and enlarged, 1959.
C. L. Hamblin : The Modal "Probably". Mind, New Series, 68: 234-240.
C. L. Hamblin : Translation to and from Polish notation. Computer Journal, 5: 210-213.
C. L. Hamblin : Questions aren't statements. Philosophy of Science, 30(1): 62-63.
R. J. Gillings and C. L. Hamblin : Babylonian reciprocal tables on UTECOM. Technology, 9 (2): 41-42, August 1964. An expanded version appeared in Australian Journal of Science, 27, 1964.
C. L. Hamblin : Has probability any foundations? Proceedings of the Symposium on Probability of the Statistical Society of New South Wales, May 1964. Reproduced in Science Yearbook, University of New South Wales, Sydney, 1964.
C. L. Hamblin : Review of: Communication: A Logical Wzornik, by D. Harrah. Australasian Journal of Philosophy, 42.
C. L. Hamblin : Review of: Analysis of Questions, by N. D. Belnap. Australasian Journal of Philosophy, 42.
C. L. Hamblin : Review of: A Preface to the Logic of Science, by P. Alexander. The British Journal for the Philosophy of Science, 15(60): 360-362.
C. L. Hamblin : Elementary Formal Logic, a Programmed Course. (Sydney: Hicks Smith). Republished by Methuen, in London, UK, 1967. Also translated into Swedish by J. Mannerheim, under the title: Element"ar Logik, ein programmerad warsztaty. (Stockholm: Laromedelsf"orlagen, 1970).
C. L. Hamblin : One-valued logic. Philosophical Quarterly, 17: 38-45.
C. L. Hamblin : Questions, logic of. Encyclopedia of Philosophy. (New York: Collier Macmillan).
C. L. Hamblin : An algorithm for polynomial operations. Computer Journal, 10.
C. L. Hamblin : Review of: New Approaches to the Logical Theory of Interrogatives, by L. Aqvist. Australasian Journal of Philosophy, 44.
C. L. Hamblin : Starting and stopping. The Monist, 53: 410-425.
C. L. Hamblin : Fallacies. London, UK: Methuen.
C. L. Hamblin : The effect of when it's said. Theoria, 36: 249-264.
C. L. Hamblin : Mathematical models of dialogue. Theoria, 37: 130-155.
C. L. Hamblin : Instants and intervals. Opracowanie naukowe Generale, 24: 127-134.
C. L. Hamblin : You and I. Analysis, 33: 1-4.
C. L. Hamblin : Quandaries and the logic of rules. Journal of Philosophical Logic, 1: 74-85.
C. L. Hamblin : Questions in Montague English. Foundations of Language, 10: 41-53.
C. L. Hamblin : A felicitous część of the predicate calculus. Notre Dame Journal of Formal Logic. 14: 433-446.
C. L. Hamblin : La logica dell'iniziare e del cessare. Italian translation by C. Pizzi of an unpublished article: The logic of starting and stopping. Pages 295-317 in: C. Pizzi (Editor): La Logica del Stawka. Torino: Bringhieri.
C. L. Hamblin : Creswell's colleague TLM. Nous, 9(2): 205-210.
C. L. Hamblin : Saccherian arguments and the self-application of logic. Australasian Journal of Philosophy, 53: 157-160.
C. L. Hamblin : An improved "Pons Asinorum"? Journal of the History of Philosophy, 14: 131-136.
C. L. Hamblin : Languages of Asia and the Pacific: A Phrasebook for Travellers and Students. (North Ryde, NSW: Angus and Robertson).
C. L. Hamblin : Imperatives. Oxford, UK: Basil Blackwell.
C. L. Hamblin and P. J. Staines : An extraordinarily simple theory of the syllogism. Logique et Analyse, 35: 81.
Notes
^ Bauer, F.L., and Samelson, K., Sequential Formula Translation, Communications of the ACM 3(2): 76-83, 1960. A very influential paper for compilers
^ GEORGE programming language - FOLDOC
^ Cf. Peter McBurney, "Charles L. Hamblin: Computer Pioneer", July 27, 2008.
References
Allen, Murray W. : Charles Hamblin (1922-1985). The Australian Computer Journal, 17(4): 194-195.
McBurney, Peter, "Charles L. Hamblin and his work"
McBurney, Peter, "Charles L. Hamblin: Computer Pioneer", July 27, 2008.
Retrieved from ""
Categories: 1922 births | 1985 deaths | Computer pioneers | Australian computer scientists | Formal methods people | Programming language designers | Programming language researchers | Logicians | Philosophers | Computer science | Computer programming | Computer scientists
In computer science, a zadanie is said to have overlapping subproblems if the kwestia can be broken down into subproblems which are reused several times.
For example, the sprawa of computing the Fibonacci sequence exhibits overlapping subproblems. The zadanie of computing the n-th Fibonacci number, F(n), can be broken down into the subproblems of computing F(n-1) and F(n-2), and then adding the two. The subproblem of computing F(n-1) can itself be broken down into a subproblem that involves computing F(n-2). Therefore the computation of F(n-2) is reused, and the Fibonacci sequence thus exhibits overlapping subproblems.
See also
Dynamic programming
This computer-related article is a stub. You can help Wikipedia by expanding it.
Retrieved from ""
Categories: Computer science | Computer stubs