Combining Simultaneous Values and Temporal Data Dependencies
نویسندگان
چکیده
In temporal databases there are situations where multiple values of the same data item have overlapping validity times. In addition to the common case of multi-valued properties, there are several possible semantics to multiple values with overlapping validity times of the same data item. We refer to such data items as having simultaneous values. This paper presents a polynomial algorithm for eecient handling of simultaneous values in a database with temporal data dependencies|integrity rules that deene relationships among values of diierent data items in a temporal database. The algorithm is demonstrated using a case study from the game theory area. An implementation of the algorithm is integrated in a prototype of a temporal active database.
منابع مشابه
A Multiagent Update Process in a Database with Temporal Data Dependencies and Schema Versioning
Temporal data dependencies are high-level linguistic constructs that define relationships among values of data-elements in temporal databases. These constructs enable the support of schema versioning as well as the definition of consistency requirements for a single time-point and among values in different time-points. In this paper, we present a multiagent update process in a database with tem...
متن کاملSimultaneous Determination of Ibuprofen and Caffeine in Urine Samples by Combining MCR-ALS and Excitation-emission Data
Second order advantage of excitation-emission fluorescence matrix was applied for the simultaneous determination of ibuprofen and caffeine. The proposed method is based on the measurement of the native fluorescence and recording emission spectra of ibuprofen and caffeine in different excitation wavelengths. The mixture of these compounds was resolved by multivariate curve resolution coupled wit...
متن کاملCombining Neural Network with Genetic Algorithm for prediction of S4 Parameter using GPS measurement
The ionospheric plasma bubbles cause unpredictable changes in the ionospheric electron density. These variations in the ionospheric layer can cause a phenomenon known as the ionospheric scintillation. Ionospheric scintillation could affect the phase and amplitude of the radio signals traveling through this medium. This phenomenon occurs frequently around the magnetic equator and in low latitu...
متن کاملDeveloping a Course Recommender by Combining Clustering and Fuzzy Association Rules
Each semester, students go through the process of selecting appropriate courses. It is difficult to find information about each course and ultimately make decisions. The objective of this paper is to design a course recommender model which takes student characteristics into account to recommend appropriate courses. The model uses clustering to identify students with similar interests and skills...
متن کاملA Methodology for Unified Assessment of Physical and Geographical Dependencies of Wide Area Measurement Systems in Smart Grids
Wide Area Measurement Systems (WAMS) enable real time monitoring and control of smart grids by combining digital measurement devices, communication and control systems. As WAMS consist of various infrastructures, they imply complex dependencies among their underlying systems and components of different types, such as cyber, physical and geographical dependencies. Although several works exist in...
متن کامل