scholarly journals On Turing Machines Deciding According to the Shortest Computations

Axioms ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 304
Author(s):  
Florin Manea
Keyword(s):  
Computational Complexity ◽  
Turing Machine ◽  
Polynomial Time ◽  
Point Of View ◽  
The Other ◽  
Input Word ◽  
Turing Machines ◽  
Other Hand

In this paper we propose and analyse from the computational complexity point of view several new variants of nondeterministic Turing machines. In the first such variant, a machine accepts a given input word if and only if one of its shortest possible computations on that word is accepting; on the other hand, the machine rejects the input word when all the shortest computations performed by the machine on that word are rejecting. We are able to show that the class of languages decided in polynomial time by such machines is PNP[log]. When we consider machines that decide a word according to the decision taken by the lexicographically first shortest computation, we obtain a new characterization of PNP. A series of other ways of deciding a language with respect to the shortest computations of a Turing machine are also discussed.

On the Complexity of Deadlock Recovery

1986 ◽  
Vol 9 (3) ◽  
pp. 323-342
Author(s):  
Joseph Y.-T. Leung ◽  
Burkhard Monien
Keyword(s):  
Computational Complexity ◽  
Polynomial Time ◽  
Arbitrary Number ◽  
The Other ◽  
Np Hard ◽  
Total Cost ◽  
Other Hand ◽  
Input Parameters ◽  
Resource Type

We consider the computational complexity of finding an optimal deadlock recovery. It is known that for an arbitrary number of resource types the problem is NP-hard even when the total cost of deadlocked jobs and the total number of resource units are “small” relative to the number of deadlocked jobs. It is also known that for one resource type the problem is NP-hard when the total cost of deadlocked jobs and the total number of resource units are “large” relative to the number of deadlocked jobs. In this paper we show that for one resource type the problem is solvable in polynomial time when the total cost of deadlocked jobs or the total number of resource units is “small” relative to the number of deadlocked jobs. For fixed m ⩾ 2 resource types, we show that the problem is solvable in polynomial time when the total number of resource units is “small” relative to the number of deadlocked jobs. On the other hand, when the total number of resource units is “large”, the problem becomes NP-hard even when the total cost of deadlocked jobs is “small” relative to the number of deadlocked jobs. The results in the paper, together with previous known ones, give a complete delineation of the complexity of this problem under various assumptions of the input parameters.

scholarly journals Alternating Turing machines and the analytical hierarchy

10.29007/t77g ◽  
2018 ◽  
Author(s):  
Daniel Leivant
Keyword(s):  
Computational Complexity ◽  
Polynomial Time ◽  
Recursion Theory ◽  
Turing Machines ◽  
Arithmetical Hierarchy ◽  
Definition Of ◽  
Alternating Turing Machines ◽  
Insight Into ◽  
Computably Enumerable

We use notions originating in Computational Complexity to provide insight into the analogies between computational complexity and Higher Recursion Theory. We consider alternating Turing machines, but with a modified, global, definition of acceptance. We show that a language is accepted by such a machine iff it is Pi-1-1. Moreover, total alternating machines, which either accept or reject each input, accept precisely the hyper-arithmetical (Delta-1-1) languages. Also, bounding the permissible number of alternations we obtain a characterization of the levels of the arithmetical hierarchy..The novelty of these characterizations lies primarily in the use of finite computing devices, with finitary, discrete, computation steps. We thereby elucidate the correspondence between the polynomial-time and the arithmetical hierarchies, as well as that between the computably-enumerable, the inductive (Pi-1-1), and the PSpace languages.

Mustapha and Greville

2017 ◽  
pp. 145-158
Author(s):  
Önder Çakırtaş
Keyword(s):  
Point Of View ◽  
The Other ◽  
Historical Background ◽  
English Renaissance ◽  
Dramatic Works ◽  
Other Hand ◽  
Fulke Greville ◽  
Islamic Politics ◽  
Shed Light

Whilst Jonathan Burton—deactivating or mincing matters with Said's Orientalism—coined the word ‘trafficking' for the repercussions of Eastern/Islamic/Ottomanic characterization of Western authors, Linda McJannet, on the other hand—backing Said's Orientalism—went into Bakhtin's ‘heteroglossia', and stressed the polyphonic representation of dramatic works through the word ‘pragmatic ambivalence', a characterization of English authors toward the Islamic politics. Both Burton and McJannet touched pre-eminently on the Renaissance writers to define their literariness. The present chapter aims to shed light on the historical background and dramatic representation regarding Mustapha's tragic death through majoring Anglo-Ottoman diplomacy and producing a base for Machiavellian point of view. The study is based on a dramatic work of an English Renaissance playwright, Fulke Greville, who adapted Prince Mustapha's death for the stage.

Algorithms and Turing Machines

1989 ◽  
Author(s):  
Roger Penrose ◽  
Martin Gardner
Keyword(s):  
Elementary School ◽  
Turing Machine ◽  
Mathematical Knowledge ◽  
Ninth Century ◽  
The Other ◽  
Turing Machines ◽  
Universal Turing Machine ◽  
Other Hand ◽  
Mathematical Expressions ◽  
Mathematical Textbook

What Precisely is an algorithm, or a Turing machine, or a universal Turing machine? Why should these concepts be so central to the modern view of what could constitute a ‘thinking device’? Are there any absolute limitations to what an algorithm could in principle achieve? In order to address these questions adequately, we shall need to examine the idea of an algorithm and of Turing machines in some detail. In the various discussions which follow, I shall sometimes need to refer to mathematical expressions. I appreciate that some readers may be put off by such things, or perhaps find them intimidating. If you are such a reader, I ask your indulgence, and recommend that you follow the advice I have given in my ‘Note to the reader’ on p. viii! The arguments given here do not require mathematical knowledge beyond that of elementary school, but to follow them in detail, some serious thought would be required. In fact, most of the descriptions are quite explicit, and a good understanding can be obtained by following the details. But much can also be gained even if one simply skims over the arguments in order to obtain merely their flavour. If, on the other hand, you are an expert, I again ask your indulgence. I suspect that it may still be worth your while to look through what I have to say, and there may indeed be a thing or two to catch your interest. The word ‘algorithm’ comes from the name of the ninth century Persian mathematician Abu Ja’far Mohammed ibn Mûsâ alKhowârizm who wrote an influential mathematical textbook, in about 825 AD, entitled ‘Kitab al-jabr wa’l-muqabala’. The way that the name ‘algorithm’ has now come to be spelt, rather than the earlier and more accurate ‘algorism’, seems to have been due to an association with the word ‘arithmetic’. (It is noteworthy, also, that the word ‘algebra’ comes from the Arabic ‘al-jabr’ appearing in the title of his book.) Instances of algorithms were, however, known very much earlier than al-Khowârizm’s book.

Can the Academic Self-Concept be Positive and Realistic?

2005 ◽  
Vol 19 (3) ◽  
pp. 129-132 ◽  
Author(s):  
Reimer Kornmann
Keyword(s):  
Academic Performance ◽  
Opposite Effect ◽  
Self Esteem ◽  
Point Of View ◽  
The Other ◽  
Self Concept ◽  
High Ability ◽  
Self Image ◽  
Other Hand

Summary: My comment is basically restricted to the situation in which less-able students find themselves and refers only to literature in German. From this point of view I am basically able to confirm Marsh's results. It must, however, be said that with less-able pupils the opposite effect can be found: Levels of self-esteem in these pupils are raised, at least temporarily, by separate instruction, academic performance however drops; combined instruction, on the other hand, leads to improved academic performance, while levels of self-esteem drop. Apparently, the positive self-image of less-able pupils who receive separate instruction does not bring about the potential enhancement of academic performance one might expect from high-ability pupils receiving separate instruction. To resolve the dilemma, it is proposed that individual progress in learning be accentuated, and that comparisons with others be dispensed with. This fosters a self-image that can in equal measure be realistic and optimistic.

A Nabatean port on the Red Sea: note on the pottery finds from al-Qusayr (al-Wajh, Saudi Arabia)

2020 ◽  
Author(s):  
Caroline Durand
Keyword(s):  
Saudi Arabia ◽  
19Th Century ◽  
Red Sea ◽  
Point Of View ◽  
The Other ◽  
Trade Routes ◽  
Other Hand ◽  
Roman Egypt ◽  
Pottery Sherds ◽  
First Time

Al-Qusayr is located 40 km south of modern al-Wajh, roughly 7 km from the eastern Red Sea shore. This site is known since the mid-19th century, when the explorer R. Burton described it for the first time, in particular the remains of a monumental building so-called al-Qasr. In March 2016, a new survey of the site was undertaken by the al-‘Ula–al-Wajh Survey Project. This survey focused not only on al-Qasr but also on the surrounding site corresponding to the ancient settlement. A surface collection of pottery sherds revealed a striking combination of Mediterranean and Egyptian imports on one hand, and of Nabataean productions on the other hand. This material is particularly homogeneous on the chronological point of view, suggesting a rather limited occupation period for the site. Attesting contacts between Mediterranean merchants, Roman Egypt and the Nabataean kingdom, these new data allow a complete reassessment of the importance of this locality in the Red Sea trade routes during antiquity.

scholarly journals The Difficult alliance. Military cooperation between the ruthenian king Daniel and the Piasts of Mazovia

2020 ◽  
Vol 1 (1) ◽  
pp. 104-112
Author(s):  
Michał Skoczyński
Keyword(s):  
Scientific Literature ◽  
Point Of View ◽  
Armed Conflicts ◽  
The Other ◽  
Political Strategy ◽  
Military Cooperation ◽  
Historical Sources ◽  
Other Hand ◽  
Historical Methodology ◽  
The Military

Abstract The article presents the military cooperation between the King of Galician-Volhynian Ruthenia, Daniel Romanowicz, and the Dukes of Mazovia, Konrad and his son Siemowit. The alliance, based as a counterweight for the cooperation between the King of Hungary and the Piast princes of Lesser Poland, who were trying to conquer Ruthenia and dominate all Piast principalities in then fragmented Poland. It lasted for several decades from the 1220’s to the 1260’s and was primarly aimed at mutual protection against the invasions of the pagan Yotvingians and supporting each other in armed conflicts. The text contains an analysis of war expeditions, tactics and ways of support that were given by both sides of the allianace. It is a new point of view on this aspect of political strategy of both sides that in some ways defined the regional situation. Ruthenians granted masovian Piasts some mobile and political uncommited support in fight with their relatives in Poland, and also secured their border with the Yotvingians. On the other hand, masovian knights were an additional strike force in ruthenian plundering expeditions to Yotvingia. The research was based on the analysis of preserved historical sources and scientific literature using historical methodology.

scholarly journals Health and Illness as Enacted Phenomena

Topoi ◽  
2021 ◽  
Author(s):  
Fredrik Svenaeus
Keyword(s):  
Good Life ◽  
Point Of View ◽  
The Other ◽  
Lived Body ◽  
Existential Feelings ◽  
Other Hand ◽  
Health And Illness ◽  
Chronic Anxiety ◽  
Phenomenological View ◽  
Life Projects

AbstractIn this paper I explore health and illness through the lens of enactivism, which is understood and developed as a bodily-based worldly-engaged phenomenology. Various health theories – biomedical, ability-based, biopsychosocial – are introduced and scrutinized from the point of view of enactivism and phenomenology. Health is ultimately argued to consist in a central world-disclosing aspect of what is called existential feelings, experienced by way of transparency and ease in carrying out important life projects. Health, in such a phenomenologically enacted understanding, is an important and in many cases necessary part of leading a good life. Illness, on the other hand, by such a phenomenological view, consist in finding oneself at mercy of unhomelike existential feelings, such as bodily pains, nausea, extreme unmotivated tiredness, depression, chronic anxiety and delusion, which make it harder and, in some cases, impossible to flourish. In illness suffering the lived body hurts, resists, or, in other ways, alienates the activities of the ill person.

Negation and Disjunction in Anatolian—and elsewhere

1975 ◽  
Vol 25 ◽  
pp. 157-168 ◽  
Author(s):  
Anna Morpurgo Davies
Keyword(s):  
Point Of View ◽  
The Other ◽  
Other Hand

1. In the article which precedes Mr. Hawkins has proposed the readings NEG2 and NEG3 for the signs of Hieroglyphic Luwian and has argued that these logograms had the phonetic values na and ni respectively. These readings are supported by internal evidence and do not require any further justification, but it is necessary to see how plausible their consequences are from the linguistic point of view.1.1. The discovery of two negative particles, a prohibitive ni and a factual na, is welcome. Hieroglyphic now joins Cun. Luwian (prohibitive nis, factual nawa), Lycian (prohibitive ni, nipe, factual ne, nepe) and Hittite (prohibitive lē, factual natta). It is not as yet absolutely certain that Palaic does not make any distinction between prohibitive and factual negatives: the particles ni and nit are relatively frequent, but it is not altogether clear whether they occur or not in prohibitions. On the other hand it is normally assumed that Lydian has generalized one negative (nid “not”, nik “and not”) for both types of sentence.

Les "Noms de Qualite", Syntaxe ou Semantique?

1988 ◽  
Vol 12 (1) ◽  
pp. 157-179
Author(s):  
Francis Gandon
Keyword(s):  
Point Of View ◽  
The Other ◽  
Other Hand ◽  
Main Statement ◽  
Quality Distinction ◽  
The Relationship

The first part of this paper presents the position of the discussion: must a node Quality be assumed to describe "non classifying" nouns? N. Ruwet objects to this theoretical attitude as developped by J.-C. Milner. First is considered the DISQUAL (qualitative dislocation) transformation as unable to describe all the positions of the Quality nouns: the extra-posed dislocation is often impossible and, according to the position within the sentence, the relationship between thema and rhema will be modified. The criterium of dependence between the Quality noun and the main statement is not strict, on the other hand. No definite boundary between syntax and semantics can be drawn within the field considered. Another point develops the "syntactic pun" (Milner). The Qualitative question is eventually referred to Opacity and replaced inside an enonciative frame as a particular kind of "shifting out." Though the Class/Quality distinction operates as continuous (Ruwet), it cannot be separated of a general paradigm elsewhere developped (psychoanalysis, ethnology, semantics, etc.). Though not entirely descriptively adequate Milner's point of view is justified.

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