The directional relationship of spatial objects is an important spatial relationship of GIS, which is involved in spatial database query, spatial position, and spatial analysis etc. The directional relations in GIS are most commonly represented with qualitative representation model and quantitative representation model. The quantitative models represent direction relationships by angle (quadran...

Object-relation data models represent eeorts in extending object-oriented data models to incorporate higher level constructs for relating objects. Object-relation data models put explicit relations on the same \level" as types, consequently the relation construct should be a modeling construct which is well integrated with inheritance for object types. Most attempts let the relationships be spe...

Many information systems store their objects in a relational database. If the object schema or the relational schema of an application can change often or in an independent way, it is useful to let a persistent framework manage the connection between objects and relations. MORM is a model for describing meet-in-the-middle mappings between objects and relations, to support the transparent manage...

We consider ways to improve the performance of unsupervised plan and activity recognition techniques by considering temporal and object relations in addition to postural data. Temporal relationships can help recognize activities with cyclic structure and are often implicit because plans have degrees of ordering actions. Relations with objects can help disambiguate observed activities that other...

We introduce object-oriented information system into rough set models .To accomplish this, we construct the class, object, and name structures using rough set theory. Next, combining class, name and object structures, we propose objectoriented information systems. Moreover, we introduce indiscernibility relations on the set of objects, lower and upper approximations, and object-oriented rough s...