scholarly journals Non-Monotonic Ontology-based Abstractions of Data Services

2020 ◽  
Author(s):  
Gianluca Cima ◽  
Maurizio Lenzerini ◽  
Antonella Poggi
Keyword(s):  
Great Majority ◽  
Data Access ◽  
Expressive Power ◽  
Domain Ontology ◽  
Simple Extension ◽  
Data Services ◽  
Special Cases ◽  
Data Layer ◽  
Technical Details ◽  
The One

In Ontology-Based Data Access (OBDA), a domain ontology is linked to the data sources of an organization in order to query, integrate and manage data through the concepts and relations of the domain of interest, thus abstracting from the technical details of the data layer implementation. While the great majority of contributions in OBDA in the last decade have been concerned with the issue of computing the answers of queries expressed over the ontology, recent papers address a different problem, namely the one of providing suitable abstractions of data services, i.e., characterizing or explaining the semantics of queries over the sources in terms of queries over the domain ontology. Current works on this subject are based on expressing abstractions in terms of unions of conjunctive queries (UCQs) over the ontology. In this paper we advocate the use of a non-monotonic language for this task. As a first contribution, we present a simple extension of UCQs with non-monotonic features, and show that non-monotonicity provides more expressive power in characterizing the semantics of data services. A second contribution is to prove that, similarly to the case of monotonic abstractions, depending on the expressive power of the languages used to specify the various components of the OBDA system, there are cases where neither perfect nor approximated abstractions exist for a given data service. As a third contribution, we single out interesting special cases where the existence of abstractions is guaranteed, and we present algorithms for computing such abstractions in these cases.

scholarly journals Semantic Characterization of Data Services through Ontologies

2019 ◽  
Author(s):  
Gianluca Cima ◽  
Maurizio Lenzerini ◽  
Antonella Poggi
Keyword(s):  
Complexity Analysis ◽  
Data Access ◽  
Domain Ontology ◽  
Data Sources ◽  
Formal Semantic ◽  
Data Service ◽  
Data Services ◽  
Formal Framework ◽  
Semantic Layer

We study the problem of associating formal semantic descriptions to data services. We base our proposal on the Ontology-based Data Access paradigm, where a domain ontology is used to provide a semantic layer mapped to the data sources of an organization. The basic idea is to explain the semantics of a data service in terms of a query over the ontology. We illustrate a formal framework for this problem, based on the notion of source-to-ontology (s-to-o) rewriting, which comes in three variants, called sound, complete and perfect, respectively. We present a thorough complexity analysis of two computational problems, namely verification (checking whether a query is an s-to-o rewriting of a given data service), and computation (computing an s-to-o rewriting of a data service).

Methods of rendering Golgi-sublimate Preparations permanent by Platinum Substitution

1901 ◽  
Vol 47 (197) ◽  
pp. 327-330
Author(s):  
W. Ford Robertson ◽  
James H. Macdonald
Keyword(s):  
Nervous System ◽  
Good Condition ◽  
Great Majority ◽  
Golgi Method ◽  
The Other ◽  
Careful Attention ◽  
Pathological Changes ◽  
Cover Glass ◽  
Technical Details ◽  
The One

All histologists who have worked with the silver and sublimate methods of Golgi have experienced the great inconvenience arising from the facts that the preparations are not durable, and that in mounting them a cover-glass cannot be employed in the ordinary way. Preparations by the silver method generally remain in good condition for a somewhat longer period than those by the sublimate method; Golgi has indeed stated he has some which have remained unaltered for nine years. The sublimate method is now most commonly employed in the form of the modification of Cox, in which only one fluid is required instead of two. In preparing sections of tissues that have been kept for the necessary time in this fluid, it is practically essential to blacken the originally steel-grey deposit by one or other of the several methods by which this may now be done. Such preparations, when new, are probably unsurpassed by those obtained by any other Golgi-method; but, unfortunately, when mounted in the orthodox manner without a cover-glass, and in spite of the most careful attention to various other technical details that have been recommended for the purpose of increasing their durability, they almost constantly show disintegration of the black deposit in from four to six months, and are certainly absolutely useless within a year. Ever since Golgi's methods came into use, histologists have been endeavouring to find some means of overcoming this great disadvantage of want of durability of the preparations. The only measure of success that has so far been achieved is that obtained by means of various processes of gold toning. All gold methods are, however, notoriously uncertain in their results. This, of course, simply means that in carrying them out it is necessary to fulfil certain very precise conditions, and that these conditions are as yet imperfectly understood. Certainly the gold toning processes that have been recommended for rendering Golgipreparations permanent are no exception to this rule. Our own observations and experiments have been made chiefly upon sections of tissues preserved in Cox's solution, because we are convinced that Cox's method is for various reasons the most trustworthy process of this class that has yet been devised, and therefore the one most likely to be of service in studying pathological changes. We have tried the methods of Obregia and Golgi for toning sublimate sections with gold. With that of the former we have not had any success. On the other hand, with that of the latter (as briefly described in Jack's translation of Pollack's Methods of Staining the Nervous System) we have obtained some very beautiful purple-black preparations, which have now remained unchanged under a cover-glass for considerably over a year. In the great majority of instances, however, the results have been unsatisfactory, the deposit rapidly undergoing disintegration.

scholarly journals When to Substitute a Missing Upper Lateral With a Canine: A Simplified Approach

2021 ◽  
pp. 030157422098054
Author(s):  
Renu Datta
Keyword(s):  
Anterior Segment ◽  
Specific Treatment ◽  
Simplified Approach ◽  
Special Cases ◽  
Randomized Control ◽  
The One ◽  
Individual Presentation ◽  
Available Information ◽  
Missing Tooth ◽  
Made In

Introduction: The upper lateral incisor is the most commonly missing tooth in the anterior segment. It leads to esthetic and functional imbalance for the patients. The ideal solution is the one that is most conservative and which fulfills the functional and esthetic needs of the concerned individual. Canine substitution is evolving to be the treatment of choice in most of the cases, because of its various advantages. These are special cases that need more time and effort from the clinicians due to space discrepancy in the upper and lower arches, along with the presentation of individual malocclusion. Aims and Objectives: Malocclusion occurring due to missing laterals is more complex, needing more time and effort from the clinicians because of space discrepancy, esthetic compromise, and individual presentation of the malocclusion. An attempt has been made in this article to review, evaluate, and tabulate the important factors for the convenience of clinicians. Method: All articles related to canine substitution were searched in the electronic database PubMed, and the important factors influencing the decision were reviewed. After careful evaluation, the checklist was evolved. Result: The malocclusions in which canine substitution is the treatment of choice are indicated in the tabular form for the convenience of clinicians. Specific treatment-planning considerations and biomechanics that can lead to an efficient and long-lasting result are also discussed. Conclusion: The need of the hour is an evidence-based approach, along with a well-designed prospective randomized control trial to understand the importance of each factor influencing these cases. Until that time, giving the available information in a simplified way can be a quality approach to these cases.

Roma and Constantinopolis in Late-Antique Art From 312 to 365

1947 ◽  
Vol 37 (1-2) ◽  
pp. 135-144 ◽  
Author(s):  
J. M. C. Toynbee
Keyword(s):  
Religious Belief ◽  
Great Majority ◽  
Complex Problem ◽  
The Other ◽  
Late Antique ◽  
Public Monuments ◽  
The One ◽  
Independent Existence ◽  
Res Publica

Little more than a decade after Constantine's conversion to Christianity the ancient gods and goddesses of the Graeco-Roman pantheon ceased to appear upon the official coinage and public monuments of the Empire. The personifications—Victoria, Virtus, Pax, Libertas, Securitas, etc., and the ‘geographical’ figures of Res Publica, Roma, Tellus, cities, countries, and tribes—remained. Yet some of these had, up to that very time, received, like the Olympians, their shrines and altars and other honours associated with pagan cultus; and we ask ourselves how it was that a Christian State, while rejecting the one, could retain and ‘baptize’ the other. The answer to this question, which involves the whole complex problem of the nature of pagan religious belief under the later Empire, can only be tentatively suggested here. The pantheon had eventually to go because its denizens had possessed, for the great majority of pagans, a real, objective, and independent existence.

scholarly journals Social engineers and myth-busters: A comparative research on Lithuanian, Norwegian and Serbian language experts

2020 ◽  
pp. 292-344
Author(s):  
Vuk Vukotić
Keyword(s):  
News Media ◽  
Language Ideologies ◽  
Great Majority ◽  
Online News ◽  
The Other ◽  
Striking Similarity ◽  
The Public ◽  
Other Hand ◽  
The Public Sphere ◽  
The One

This article compares the language ideologies of language experts (both academic and non-academic) in online news media in Lithuania, Norway and Serbia. The results will reveal that language is understood in diametrically opposed ways amongst Lithuanian and Serbian academic experts on the one, and Norwegian academic experts on the other hand. Lithuanian and Serbian academic experts are influenced by modernist ideas of language as a single, homogenous entity, whose borders ideally match the borders of an ethnic group. Norwegian academic experts function in the public sphere as those who try to deconstruct the modernist notion of language by employing an understanding of language as a cognitive tool that performs communicative and other functions. On the other hand, non-academic experts in all the three countries exhibit a striking similarity in their language ideologies, as the great majority expresses modernist ideals of language.

Una aproximación empírica a la ­clasificación y traducción de las figuras retóricas en la publicidad

Babel ◽  
2011 ◽  
Vol 57 (1) ◽  
pp. 32-57 ◽  
Author(s):  
Maria Calzada Perez
Keyword(s):  
Empirical Investigation ◽  
Great Majority ◽  
Translation Studies ◽  
The Other ◽  
Translation Process ◽  
New Rhetoric ◽  
Rhetorical Figures ◽  
Ancient Times ◽  
The One

Since ancient times the suasive value of rhetorical figures has been vastly studied. In fact, Aristotle himself argued that the aim of rhetoric was not just to persuade but to find the best methods of persuasion (Aristotle, Retorica, ed. 1990). These methods have been frequently used in advertising, where they are employed to capture the consumer’s attention and, consequently, to sell the advertised product. However (despite the frequent appearance of rhetorical figures in advertising), there is a scarcity of studies on the role of these persuasive mechanisms in the translation of publicity. Bearing upon the “new rhetoric”, the present paper has a twofold purpose. On the one hand, it aims to import a clear taxonomy of rhetorical figures from advertising into translation studies and subsequently to illustrate the transfer of these figures. On the other hand, it analyses the behaviour of rhetorical figures in the translation process by means of an empirical investigation whose goal it is to further categorise them in a systematic and rational way. Drawing upon the seminal work of McQuarrie and his collaborators, the paper performs a quantitative analysis of a corpus of 120 matching pairs consisting of English advertisements and their existing Spanish counterparts. Results evidence that a great majority of rhetorical figures are “translated”, thus confirming the globalising tendencies of advertising.

What Italian business disliked about a European common market

2008 ◽  
Vol 49 (2) ◽  
Author(s):  
Francesca Fauri
Keyword(s):  
Great Majority ◽  
Production Costs ◽  
Export Market ◽  
Export Demand ◽  
Italian Economy ◽  
Key Factor ◽  
Treaty Of Rome ◽  
The One ◽  
Medium Firms ◽  
Opening Up

AbstractThe possibility of enlarging Italy’s export market was the key factor that made industrialists repeatedly express their consent for a unified market, even in their earliest statements on the matter. The great majority of Italian business declared itself in favour of a united market dependent upon a given set of conditions: gradual abolition of tariffs, leveling of production costs among members, free circulation of workers (as well as of goods and capital) and inclusion in the Treaty of Art.109 on the resumption of tariff controls or measures of safeguard where a sudden crisis in the balance of payments occurs.The policy of Italian business towards EEC integration in those years was the result of a compromise between protectionist sectors (small-medium firms) on the one hand and, on the other, firms belonging to the so-called automobile cycle (Fiat, Pirelli etc.) and the engineering sector, whose growth had been led by export demand and favoured opening up the Italian economy to international competition.Once the Treaty of Rome was signed, there were issues that Italian industrialists did not like. However, on the whole, participation was never called into question and, despite a few skeptical voices, Italian business valued European integration as a unique opportunity to enlarge the market, increase foreign demand and improve competitiveness. The Italian economic miracle had begun to take shape.

Design and Implementation of Web-Based E-Learning Platform

2014 ◽  
Vol 536-537 ◽  
pp. 599-602
Author(s):  
Yang Nan
Keyword(s):  
Online Learning ◽  
Data Access ◽  
Sql Server ◽  
Web Based ◽  
Learning Platform ◽  
Ajax Technology ◽  
E Learning ◽  
Data Layer ◽  
Overall Performance ◽  
Windows Server

This paper attends to study Windows Server and SQL Server to form a combination of the two operating systems to establish an online learning platform. The platform basically completed the user needs to achieve functional, but also focuses on the application of Ajax technology, the use of this technology at the user level can be completed without page refresh can be achieved through video effects, the data layer, it reduces the data access to the database pressure, improve the overall performance of the overall learning platform, the results show that the techniques of this paper can be used in a very good application and online learning platform.

QoS in Vehicular Communication Networks

2010 ◽  
pp. 300-325 ◽  
Author(s):  
Robil Daher ◽  
Djamshid Tavangarian
Keyword(s):  
Communication Networks ◽  
Ad Hoc ◽  
Intelligent Transportation System ◽  
Vehicular Communication ◽  
Medium Access ◽  
Data Services ◽  
High Speeds ◽  
Vehicular Communication Networks ◽  
The One ◽  
New Research

Vehicular communication networks (VCNs) have emerged as a key technology for next-generation wireless networking. DSRC/WAVE as a leading technology for VCN provides a platform for Intelligent Transportation System (ITS) services, as well as multimedia and data services. Some of these services such as active safety and multimedia services have special requirements for QoS provision. However, when providing QoS, the VCN characteristics are the cause for several new issues and challenges, especially when vehicles travel at high speeds of up to 200 km/h. These issues are addressed in the context of roadside networks and vehicular ad hoc (unplanned) networks (VANETs), including vehicle-to-vehicle (V2V) and vehicle-to-roadside (V2R) communications. Accordingly, plenty of solutions for provisioning QoS in VCNs have been classified in regards to VANETs and roadside networks, on the one hand, and to layer-2 and layer-3, on the other hand. Consequently, several QoS solutions, including medium access and routing protocols, are presented and discussed. Additionally, open research issues are discussed, with an objective to spark new research interests in the presented field.

Consequences of the Bootstrap Assumptions

2020 ◽  
pp. 145-212
Author(s):  
Sergiu Klainerman ◽  
Jérémie Szeftel
Keyword(s):  
Initial Data ◽  
Bootstrap Assumption ◽  
Data Layer ◽  
The One

This chapter discusses the proof for Theorem M0, together with other first consequences of the bootstrap assumptions. The only bootstrap assumption used in the proof of Theorem M0 is the bootstrap assumption BA-D on decay for k = 0, 1 derivatives. The chapter then relies on (4.1.5) and the assumptions (4.1.1) on the initial data layer. This observation allows one to use the conclusions of Theorem M0, not only for the bootstrap spacetime M in Theorem M1–M5, but also for the extended spacetime in the proof of Theorem M8, where the only assumption is the one on decay (which is established for the extended spacetime in Theorem M7). The chapter not only improves the bootstrap assumption (4.1.7), but also gains derivatives iteratively.

Sign in / Sign up

Export Citation Format

Share Document