Deriving Identity from Extensionality

Author(s):  
A. H. M. ter Hofstede ◽  
Th. P. van der Weide

In recent years, a number of proposals have been made to extend conventional conceptual data modeling techniques with concepts for modeling complex object structures. Among the most prominent proposed concepts is the concept of collection type. A collection type is an object type of which the instances are sets of instances of another object type. A drawback of the introduction of such a new concept is that the formal definition of the technique involved becomes considerably more complex. In this paper a new kind of constraint, the extensional uniqueness constraint, is introduced, providing an alternative treatment of complex object types. The formal definition of this constraint type is presented, the advantages of its introduction are discussed, and its consequences for, among others, identification schemes are elaborated.

2012 ◽  
Vol 23 (3) ◽  
pp. 50-64
Author(s):  
Wim Laurier ◽  
Geert Poels

This research note shows that the scope of conceptual data modeling patterns can be identified, clarified, and explicitly represented by positioning them into an ontology-based framework. A clear and explicit definition of scope could help deciding which patterns match which parts of the domain to be represented. The authors demonstrate their argument by positioning existing conceptual data modeling patterns into a two-dimensional structuring framework that is constructed using two ontology-derived ‘benchmark’ patterns: an enterprise pattern for representing transactions (derived from the REA domain ontology) and an abstraction pattern for representing reality at different levels of abstraction (derived from the UFO foundational ontology). By means of an application scenario dealing with the conceptual design of a transactional enterprise database, the authors illustrate how the framework can be used to evaluate the relevancy and completeness of candidate patterns with respect to the problem at hand.


Author(s):  
С.И. Рябухин

Процессные модели предметной области широко применяются при проектировании баз данных, а именно в ходе концептуального моделирования данных. Предлагается решение проблемы неоднозначности преобразования процессных доменных моделей типа SADT в концептуальные модели данных. Domain process models are widely used in database design, namely in conceptual data modeling. The solution of the problem of ambiguity of transformation of process domain models of the SADT type into conceptual data models is proposed.


IEEE Expert ◽  
1989 ◽  
Vol 4 (1) ◽  
pp. 50-61 ◽  
Author(s):  
J.P. Held ◽  
J.V. Carlis

2021 ◽  
Vol 1752 (1) ◽  
pp. 012082
Author(s):  
Nurdin ◽  
S F Assagaf ◽  
F Arwadi

2014 ◽  
Vol 532 ◽  
pp. 113-117
Author(s):  
Zhou Jin ◽  
Ru Jing Wang ◽  
Jie Zhang

The rotating machineries in a factory usually have the characteristics of complex structure and highly automated logic, which generated a large amounts of monitoring data. It is an infeasible task for uses to deal with the massive data and locate fault timely. In this paper, we explore the causality between symptom and fault in the context of fault diagnosis in rotating machinery. We introduce data mining into fault diagnosis and provide a formal definition of causal diagnosis rule based on statistic test. A general framework for diagnosis rule discovery based on causality is provided and a simple implementation is explored with the purpose of providing some enlightenment to the application of causality discovery in fault diagnosis of rotating machinery.


Viruses ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 569 ◽  
Author(s):  
Lize Cuypers ◽  
Pieter Libin ◽  
Peter Simmonds ◽  
Ann Nowé ◽  
Jorge Muñoz-Jordán ◽  
...  

Dengue virus (DENV) is estimated to cause 390 million infections per year worldwide. A quarter of these infections manifest clinically and are associated with a morbidity and mortality that put a significant burden on the affected regions. Reports of increased frequency, intensity, and extended geographical range of outbreaks highlight the virus’s ongoing global spread. Persistent transmission in endemic areas and the emergence in territories formerly devoid of transmission have shaped DENV’s current genetic diversity and divergence. This genetic layout is hierarchically organized in serotypes, genotypes, and sub-genotypic clades. While serotypes are well defined, the genotype nomenclature and classification system lack consistency, which complicates a broader analysis of their clinical and epidemiological characteristics. We identify five key challenges: (1) Currently, there is no formal definition of a DENV genotype; (2) Two different nomenclature systems are used in parallel, which causes significant confusion; (3) A standardized classification procedure is lacking so far; (4) No formal definition of sub-genotypic clades is in place; (5) There is no consensus on how to report antigenic diversity. Therefore, we believe that the time is right to re-evaluate DENV genetic diversity in an essential effort to provide harmonization across DENV studies.


Robotica ◽  
1991 ◽  
Vol 9 (2) ◽  
pp. 203-212 ◽  
Author(s):  
Won Jang ◽  
Kyungjin Kim ◽  
Myungjin Chung ◽  
Zeungnam Bien

SUMMARYFor efficient visual servoing of an “eye-in-hand” robot, the concepts of Augmented Image Space and Transformed Feature Space are presented in the paper. A formal definition of image features as functionals is given along with a technique to use defined image features for visual servoing. Compared with other known methods, the proposed concepts reduce the computational burden for visual feedback, and enhance the flexibility in describing the vision-based task. Simulations and real experiments demonstrate that the proposed concepts are useful and versatile tools for the industrial robot vision tasks, and thus the visual servoing problem can be dealt with more systematically.


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