8 Related Work
نویسندگان
چکیده
Subrahmanian 14] uses annotated logic 2] to integrate a set of deductive databases in an unique amalgamated database called amalgam. The amalgam, in addition to the disjoint union of the databases, contains a supervisory database. The supervisory database is a set of clauses (called amalgamated clauses) which resolve connicts due to inconsistent facts and compose uncertain information of diierent database sources. 14] investigates the relation between the models of the amalgam and the models of its components. Subrahmanian takes a more general approach then ourselves as he considers formulas with complex sets of truth values and time intervals. However the intuition behind amalgamated clauses (contained in the supervisory database) is very close to that of a generalization of view constraints described in 6]. From our perspective adopting a global amalgamated database is the reason of the main drawback of Subrahmanian's approach. Indeed global amalgamated database prevents one to associate distinct deductive mechanism to each database in the system. Furthermore amalgamated database doesn't support local inconsistency. I.e. the inconsistency of a local database forces the inconsistency of the whole amalgamated database. Diierently, our approach allows an integration information state in which the i-th database is inconsistent while the other are consistent. Vermeer et al. 16] exploit the semantic information provided by the integrity constraints of the single databases to achieve interoperability among them. The spirit of this approach is similar to ours, although they mainly address a diier-ent problem. In 16] diierent databases are integrated in an unique integrated view. The consistency of such an integrated view is checked by using integrity constraints of component databases. Vermeer et al. argue that semantic relations are expressed by relationships between objects (cf. domain relations) and relations between classes are the result of object relationships (cf. deenition of satissability of domain/view constraints w.r.t. a domain relation). 9 Conclusions In this paper we have provided a formal semantics, called LMS, for the integration of information of diierent agents. We have provided two examples from the electronic commerce scenario which involve many of the challenging aspects of information integration. We have deened LMS introducing the key concepts of domain constraint and view constraint which formalize how the information of diierent agents is integrated. Then we have argued that LMS is an adequate formalism for information integration in electronic commerce by formalizing the examples presented in the paper. Finally we have compared LMS with the main formalisms …
منابع مشابه
A Study on Organizational Factors Contributing to Reduce Work-related Accidents in Zamyad Co., an Iranian Commercial Vehicle Manufacturing Company
One of the increasingly important organizational considerations involves occupational health and staff safety. Hence, it is crucial for the managers to identify the key organizational factors contributing to reduce work-related accidents. This study was conducted on 340 workers, employees, experts, supervisors, directors, and managers. The data evaluation involved a questionnaire while the anal...
متن کاملبررسی اپیدمیولوژیک مرگ های ناشی از حوادث شغلی...
Background & Aim: Trauma is the leading cause of death in patients has 3-44 of years olds. According to the report of the International Labor Organization (ILO), 1.1 million work-related deaths occur every year. Severity and prevalence of work related hazards are more obvious in developing countries. We conducted the study for better understanding of work-related mortality in Tehran. Materi...
متن کاملAnalysis of Work-Related Musculoskeletal Disorders in Nursing Occupation: A Comparative Assessment between Shift and Day Workers
Introduction: The prevalence of musculoskeletal disorders in the nursing profession has been high reported. The aim of this study was to evaluate the prevalence of musculoskeletal disorders as well as to analysis the risk factors associated with it in the nursing community. Method: This cross-sectional study was performed in seven hospitals in Khuzestan province in 2020. The study population a...
متن کاملبررسی اپیدمیولوژیک حوادث ناشی از کار ثبت شده در سازمان تأمین اجتماعی ایران (1384-1380)
Background and Objectives: Work-related injuries are considered as the third cause of mortality across the world and have been introduced as one of the health, social and economic risk factors amongst industrial and developing communities. The present epidemiologic survey aimed to assess the work-related accidents among Iranian workers who were insured by the Social Security Organisation . ...
متن کاملWork-related Rumination in Critical Care Nurses: A Cross Sectional Study in Iran
Introduction: Work-related rumination is the cause of various psychological stresses in nurses and threatens their mental health. The aim of this study was to evaluate work- related rumination and related factors in Iranian nurses working in critical care units. Methods: In this cross-sectional study, 182 nurses working in critical care units were selected by convenience sampling method. Data w...
متن کاملMeta-analysis Study of Work-related Musculoskeletal Disorders in Iran
Objective: Work-related musculoskeletal disorders are one of the major causes of lost working time, increased costs, human injuries and burnout. The International Labor Organization estimates that about 160 million work-related illnesses occur worldwide each year, where the highest prevalent illnesses are musculoskeletal disorders. Several studies have been conducted In Iran to investigate the ...
متن کامل