In this work, a new external schema definition methodology for object oriented databases (OODB) that solves some of the problems of existing methodologies is presented. In particular, this new methodology avoids the need for generating derived classes that are not directly used in the defined external schema. Also, it offers a way of integrating and reusing different external schema definitions.

abstract one of the main concerns in educational settings has been the degree of the learners’ involvement in learning and the extent to which they actively participate in classroom talks and interactions. the present study is an emic-based ethnographic study aimed at providing insights about patterns of talk and different degrees of interaction in efl university classes with a specific focus o...

this study reports on the findings of a genre teaching course for developing academic writing of a class of efl students in iran. the information report genre was taught in a cyclical way of teaching and learning, which was started from ‘setting the context’ and ‘deconstruction’ of prototype information report genre, and continued with ‘joint construction’, ‘independent construction’, and final...

Poisoning remains a major cause of hospital admission into the emergency department and intensive care unit. Proper diagnosis is the cornerstone for optimal management of poisoned patients. Since the definitive analytical confirmation of the nature of the toxicant involved in the poisoning cannot be rapidly obtained in the majority of healthcare facilities, diagnosis relies on the medical histo...

Pattern recognition systems are widely used in a host of different fields. Due to some reasons such as lack of knowledge about a method based on which the best classifier is detected for any arbitrary problem, and thanks to significant improvement in accuracy, researchers turn to ensemble methods in almost every task of pattern recognition. Classification as a major task in pattern recognition,...

Dominance-based Rough Set Approach (DRSA) was introduced as a generalization of the rough set approach for reasoning about preferences. While data describing preferences are ordinal by the nature of decision problems they concern, the ordering of data is also important in many other problems of data analysis. Even when the ordering seems irrelevant, the presence or the absence of a property (po...

Standard face recognition algorithms that use standard feature extraction techniques always suffer from image performance degradation. Recently, singular value decomposition and low-rank matrix are applied in many applications,including pattern recognition and feature extraction. The main objective of this research is to design an efficient face recognition approach by combining many tech...