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Foundations of Temporal Conceptual Data Models [chapter]

Alessandro Artale, Enrico Franconi
2009 Lecture Notes in Computer Science  
At the end, results on the complexity of reasoning in temporal conceptual models are presented.  ...  This chapter considers the different temporal constructs appeared in the literature of temporal conceptual models (timestamping and evolution constraints), and it provides a coherent model-theoretic formalisation  ...  While DLR US is an undecidable language, several decidable sub-languages can be used to reason over temporal schemas.  ... 
doi:10.1007/978-3-642-02463-4_2 fatcat:2jrkxuozmjhifbc6sptszm6jya

Modeling the Evolution of Objects in Temporal Information Systems [chapter]

A. Artale, C. Parent, S. Spaccapietra
2006 Lecture Notes in Computer Science  
We show how DLRUS is able to capture the various modeling constraints in a succinct way and to perform automated reasoning on temporal conceptual models.  ...  We consider a modeling language able to express both timestamping and evolution constraints.  ...  to reasoning over DLR − US .  ... 
doi:10.1007/11663881_3 fatcat:bjxagm22tfaa3h64bvqcmzy6da

Evolving objects in temporal information systems

Alessandro Artale, Christine Parent, Stefano Spaccapietra
2007 Annals of Mathematics and Artificial Intelligence  
We show how DLRUS is able to capture the various modelling constraints in a succinct way and to perform automated reasoning on temporal conceptual models.  ...  We consider a modelling language able to express both timestamping and evolution constraints.  ...  A complete and decidable reasoning procedure for reasoning over timestamping is provided in [6] .  ... 
doi:10.1007/s10472-007-9068-z fatcat:sltmtrxm7fcd7jjpc37hmyjsua

A Description Logic of Change

Alessandro Artale, Carsten Lutz, David Toman
2007 International Joint Conference on Artificial Intelligence  
We argue that our logic is sufficient for reasoning about temporal conceptual models with time-stamping constraints.  ...  The resulting multi-dimensional DL S5 ALCQI supports reasoning about change by allowing to express that concepts and roles change over time.  ...  This is also the first decidability result that allows reasoning in temporal conceptual models with timestamping for entities, relationships, and attributes.  ... 
dblp:conf/ijcai/ArtaleLT07 fatcat:fxt2yuemr5g7xinxosw5fncggm

Tailoring Temporal Description Logics for Reasoning over Temporal Conceptual Models [chapter]

Alessandro Artale, Roman Kontchakov, Vladislav Ryzhikov, Michael Zakharyaschev
2011 Lecture Notes in Computer Science  
On the other hand, reasoning on temporally extended DLs turn out to be too complex for effective reasoning ranging from 2EXPTIME up to undecidable languages.  ...  We propose here to temporalize the 'light-weight' DL-Lite logics obtaining nice computational results while still being able to represent various constraints of temporal conceptual models.  ...  an effective reasoning support for the construction phase of a conceptual model schema.  ... 
doi:10.1007/978-3-642-24364-6_1 fatcat:sgxj37qxijdg3hxwd6dgtby3fi

Complexity of Reasoning over Temporal Data Models [chapter]

Alessandro Artale, Roman Kontchakov, Vladislav Ryzhikov, Michael Zakharyaschev
2010 Lecture Notes in Computer Science  
We investigate the computational complexity of reasoning over temporal extensions of conceptual data models.  ...  The temporal conceptual models we analyse include the standard UML/EER ISA between entities and relationships, disjointness and covering, cardinality constraints and their refinements, multiplicity and  ...  ., decidability) results in the table above by reducing reasoning over temporal data models based on ER bool and ER ref without lifespan cardinality constraints to reasoning in temporal description logics  ... 
doi:10.1007/978-3-642-16373-9_13 fatcat:47ezucsjgvh27glunw4ekv5hqe

Reasoning on temporal class diagrams: Undecidability results

Alessandro Artale
2006 Annals of Mathematics and Artificial Intelligence  
We show that reasoning on finite models is different from reasoning on unrestricted ones.  ...  Then, we prove that reasoning on temporal class diagrams is an undecidable problem on both unrestricted models and on finite ones.  ...  It is an open problem whether reasoning is still decidable by regaining timestamping for relationships (and maintaining timestamping for classes) but dropping evolution constraints altogether.  ... 
doi:10.1007/s10472-006-9019-0 fatcat:hec5oprbkvcepbdjrloqoef72i

Semantics of time-varying information

Christian S. Jensen, Richard T. Snodgrass
1996 Information Systems  
We attempt to capture the essence of time-varying information via a very simple data model, the bitemporal conceptual data model.  ...  We discuss various representations of timestamps and the representation of the database variable \now."  ...  Our reply becomes: yes, at a representational level, but no at a conceptual level. Two of the representational models are attribute timestamped; the other four are tuple-timestamped.  ... 
doi:10.1016/0306-4379(96)00017-8 fatcat:2xkyzweponadnijh4q4kvypjui

Towards a streaming SQL standard

Namit Jain, Stan Zdonik, Shailendra Mishra, Anand Srinivasan, Johannes Gehrke, Jennifer Widom, Hari Balakrishnan, Uǧur Çetintemel, Mitch Cherniack, Richard Tibbetts
2008 Proceedings of the VLDB Endowment  
The result is a new model that gives the user control over the granularity at which one can express simultaneity. Of course, it is possible to ignore simultaneity altogether.  ...  We use the data models from Oracle and StreamBase as our examples. Oracle uses a time-based execution model while StreamBase uses a tuple-based execution model.  ...  Conceptually, ISTREAM captures tuples that are inserted to a relation (such as a window) over time, whereas DSTREAM captures the tuples that "fall out" of the relation, as used in CQL [1] .  ... 
doi:10.14778/1454159.1454179 fatcat:ebt22pdv6zejbfmgnmf3f3imte

A Nonlinear Autoregressive Exogenous (NARX) Neural Network Model for the Prediction of Timestamp Influence on Bitcoin Value

Nahla Aljojo, Areej Alshutayri, Eman Aldhahri, Seita Almandeel, Azida Zainol
2021 IEEE Access  
A better and more accurate model would be required to predict how the Timestamp influences changes of bitcoin transactions.  ...  of Bitcoin price over timestamp developed a pattern that was predicted by NARX with less That means those involved in the transaction of bitcoin at the wrong timestamp will certainly face the uncertainty  ...  Despite the fact that there is "advanced research in time series prediction," the reason for using the NARX model in this study is due to the fact that the "NARX model" predicted the timestamp data based  ... 
doi:10.1109/access.2021.3124629 fatcat:3hz3yy7r65avng53s5ix4pnup4

The Paxos Register

Harry C. Li, Allen Clement, Amitanand S. Aiyer, Lorenzo Alvisi
2007 Symposium on Reliable Distributed Systems. Proceedings  
We use our register to show how Lamport's Classic Paxos and Castro and Liskov's Byzantine Paxos are the same consensus protocol, but for different failure models.  ...  The Paxos register is a write-once register that exposes two important abstractions for reaching consensus: (i) read and write operations that capture how processes in Paxos protocols propose and decide  ...  It is difficult to characterize these similarities for three main reasons.  ... 
doi:10.1109/srds.2007.4365689 fatcat:ns2bc5o5kvg7bhszx32qci7tey

The Paxos Register

Harry C. Li, Allen Clement, Amitanand S. Aiyer, Lorenzo Alvisi
2007 2007 26th IEEE International Symposium on Reliable Distributed Systems (SRDS 2007)  
We use our register to show how Lamport's Classic Paxos and Castro and Liskov's Byzantine Paxos are the same consensus protocol, but for different failure models.  ...  The Paxos register is a write-once register that exposes two important abstractions for reaching consensus: (i) read and write operations that capture how processes in Paxos protocols propose and decide  ...  It is difficult to characterize these similarities for three main reasons.  ... 
doi:10.1109/srds.2007.32 dblp:conf/srds/LiCAA07 fatcat:7y7kz37ylbbk5ew6doozwpqvxq

Temporal entity-relationship models-a survey

H. Gregersen, C.S. Jensen
1999 IEEE Transactions on Knowledge and Data Engineering  
In the presentation of each m o d e l , the paper examines how t h e time-varying information is captured in the model and present the new concepts and modeling constructs of the model.  ...  It has been widely recognized that temporal aspects of database schemas are prevalent and di cult to model using the ER model.  ...  There are two models in which it is possible, at the conceptual level, to specify the granularity o f the timestamps.  ... 
doi:10.1109/69.774104 fatcat:kmj42o2e7zgxxmfn5ct7l42oae

OBDA for Log Extraction in Process Mining [chapter]

Diego Calvanese, Tahir Emre Kalayci, Marco Montali, Ario Santoso
2017 Lecture Notes in Computer Science  
Through process mining, decision makers can discover process models from data, compare expected and actual behaviors, and enrich models with key information about their actual execution.  ...  Process mining is an emerging area that synergically combines model-based and data-oriented analysis techniques to obtain useful insights on how business processes are executed within an organization.  ...  Ontology-Based Data Access Ontologies are used to provide the conceptualization of a domain of interest, and mechanisms for reasoning about it.  ... 
doi:10.1007/978-3-319-61033-7_9 fatcat:2v3pzulz6zdhjbd2no4lf3c3om

Sustainable Management Of Versioned Data

Martin Häusler, Ruth Breu
2017 Zenodo  
We state the requirements, provide an overview over the algorithm and a comparison with related work alongside a discussion of individual advantages, disadvantages and challenges.  ...  For that reason, we decided to choose a simple basic format and then transform more sophisticated structures into that format.  ...  For these reasons, we must not constrain our solution to a single B-Tree.  ... 
doi:10.5281/zenodo.291897 fatcat:tkp7ynhedzbz5pouhk6ppsrj4y
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