Na Tang

A workflow model based on fuzzy-timing Petri nets

Time information management in workflow has been recognized as one of the most significant tasks in workflow management. The uncertainties in time and time-related constraints in workflow models should be taken into consideration. Based on introducing time constraints on elements in fuzzy-timing Petri nets, this paper propose a new workflow model named fuzzy temporal workflow nets (FTWF-nets). The calculation of temporal elements in FTWF-nets is given. Then time modeling and time possibility analysis of temporal phenomena in FTWF-nets are investigated. Finally an example is given to illustrate how to use these methods. Research results show that FTWF-nets can be used to model time information in those workflows, which have time uncertainty and have time constraints on resources and activities, and analyze the time possibility on some constraints.

Research of temporal workflow process and resource modeling

In recent years, numerous Petri net based workflow models have been proposed. In the aspect of temporal modeling information, however, there remain some problems in these workflow models. In this paper, a new Petri Net modeling method is put forward, which systematically describes the temporal information and the relevant resources during a process of workflow activities. Finally, an example is provided to illustrate the workflow modeling process with TempWF-net.

An inference model of temporal logic in an intelligent decision support system of salary

Temporal characters due to the alteration of salary policy and salary standards are discussed in this paper. According to these characters, the authors put forward a formalization inference model of temporal logic and present a discussion of the knowledge database driven by temporal knowledge, called the temporal-driven knowledge database.

Mapping Bitemporal XML Data Model to XML Document

XML documents will be modified as time goes by. The successive versions of an XML document are expressed by temporal XML document in an incremental fashion, which provides us a high effective method for version management, so the topics of representing, querying and updating temporal XML documents have been received increasing attention. This paper presents an XML data model for tracking historical information in an XML document. This model can present the temporally ungrouped information. Two different ways of mapping this model to a (bitemporal) XML document are discussed and compared in the paper.

Temporal Knowledge Representation and Reasoning

The importance of dealing with temporal properties in knowledge representation and reasoning has attracted researchers’ attention for long. A number of temporal knowledge representation frameworks are proposed, however, few are implemented in practice. Since production system is a knowledge representation mechanism used by most knowledge based systems and expert systems in practice, in this chapter, temporal properties are integrated into traditional production system. In other words, both rules and facts process temporal attributes. Related definitions and reasoning algorithms are presented. A prototype implementation of a salary system is given to show the validity of the framework.

Bitemporal Extension and Mapping of XML Data Model

XML which is a new language for data representation is expected to become a universal format for data exchange on the Web. Generally speaking, we make some changes on XML documents as time goes by. Because temporal XML can store the successive versions of a document in an incremental fashion, it provides us a high effective method for version management. Of course, XML is more natural than RDB on representing the temporal information. So the topic of representing, querying and updating temporal information in XML has received some attention. In this paper a XML data model for tracking historical information in an XML document are proposed. After presenting an abstract model for bitemporal XML, two different ways of mapping this abstract representation into a (bitemporal) XML document are discussed. Finally all schemas are compared.

Temporal Role Hierarchies

Information security and access control is an important part of CSCD applying. RBAC (role based access control) as an access control technology using for distributed system has been widely researched these years. Role hierarchies is one component of RBAC model, it can reduce the workload of permission assignment. Nowadays most research of RBAC has no relation with timing constraint. The main purpose of this article is to study the effect of temporal constraint acting on role hierarchy. The basis of the study is RBAC96 model, first we analyse the change of role state, propose 3 forms of temporal constraint and give the expression of temporal constraint. Then we present an analysis of the effects of temporal constraint on role enabling and role activation which has various implication on a role hierarchy, and at last we formally describe a timing restricted role hierarchies model

Determinants of groupware usability for community care collaboration

Due to the special requirements of community care, software systems in this industry always have to be developed into shared-workspace groupware systems, which are claimed to achieve job performance more quickly and easily. But the adoption of this kind of systems in Australia is very little and unsuccessful so far. It is observed that the deployment of them always encounters resistance from community care real workers who must use them. One possible cause of this resistance is that the groupware usability is quite dissatisfying, which further causes that the system does not meet user expectations. This research aims to gain a deeper understanding of user perspective and expectation to the interface usability of Community Care Groupware System (CCGS) basing on the specific context of use. A task modeling method is introduced to improve the quality of groupware usability evaluation. A triangulated research methodology comprising unstructured observation, structured and semi-structured questionnaire, and unstructured interview, was conducted on 23 community care workers. Five determinants that most influence the interface usability of CCGS from user’s perspective, and several relevant suggestions that make a CCGS really usable in everyday use are elicited from data collection and analysis.