Formalization of the classification pattern: Survey of classification modeling in information systems engineering

Formalization is becoming more common in all stages of the development of information systems, as a better understanding of its benefits emerges. Classification systems are ubiquitous, no more so than in domain modeling. The classification pattern that underlies these systems provides a good case study of the move towards formalization in part because it illustrates some of the barriers to formalization; including the formal complexity of the pattern and the ontological issues surrounding the ‘one and the many’. Powersets are a way of characterizing the (complex) formal structure of the classification pattern and their formalization has been extensively studied in mathematics since Cantor’s work in the late 19th century. One can use this formalization to develop a useful benchmark. There are various communities within Information Systems Engineering (ISE) that are gradually working towards a formalization of the classification pattern. However, for most of these communities this work is incomplete, in that they have not yet arrived at a solution with the expressiveness of the powerset benchmark. This contrasts with the early smooth adoption of powerset by other Information Systems communities to, for example, formalize relations. One way of understanding the varying rates of adoption is recognizing that the different communities have different historical baggage. Many conceptual modeling communities emerged from work done on database design and this creates hurdles to the adoption of the high level of expressiveness of powersets. Another relevant factor is that these communities also often feel, particularly in the case of domain modeling, a responsibility to explain the semantics of whatever formal structures they adopt. This paper aims to make sense of the formalization of the classification pattern in ISE and surveys its history through the literature; starting from the relevant theoretical works of the mathematical literature and gradually shifting focus to the ISE literature. The literature survey follows the evolution of ISE’s understanding of how to formalize the classification pattern. The various proposals are assessed using the classical example of classification; the Linnaean taxonomy formalized using powersets as a benchmark for formal expressiveness. The broad conclusion of the survey is that (1) the ISE community is currently in the early stages of the process of understanding how to formalize the classification pattern, particularly in the requirements for expressiveness exemplified by powersets and (2) that there is an opportunity to intervene and speed up the process of adoption by clarifying this expressiveness. Given the central place that the classification pattern has in domain modeling, this intervention has the potential to lead to significant improvements.The UK Engineering and Physical Sciences Research Council (grant EP/K009923/1)

Object-Oriented Protocol Hierarchies for Distributed Workflow Systems

Distributed software systems such as groupware and workflow systems will play a key role in the near future. While numerous models which promise highly sophisticated functionality are proposed in the literature their implementation is still a difficult and very expensive task. Therefore existing systems fall far behind their promises. Entities of the workflow level are often autonomous. Consequently, they are related to each other in more than a fixed client/server configuration: they often perform their activities in collaboration. Workflow models also contain a lot of information about the system's dynamics. If one uses objects as an implementation model --- which is the most preferable of all possible choices today --- all these aspects must be mapped onto the same abstraction which is mainly concerned with functionality of entities but neglects relationships almost completely, i.e. treats entities in isolation. The dynamics is hidden inside object implementation, including and espe..

Cooperation in Object Bases through Alliances

Interaction of objects in today's object-oriented database systems is based on four premises: First, messages are procedures, which are executed instantaneously. Second, interaction is limited to two objects, a client and a server. Third, communication contexts are defined algorithmically by procedures --- or at top level --- by transactions. Fourth, all objects are globally accessible no matter where they physically reside in a computer network (location transparency). We argue in this paper that this paradigm of object interaction does not suffice for large-scale cooperative and distributed applications such as computer-integrated manufacturing (CIM), distributed artificial intelligence (DAI), or office automation which are characterized, on the one hand, by autonomously acting agents which allow for the necessary high degree of specialization to meet local computing requirements and, on the other hand, by the need for coordination among these agents. As a remedy we propose a strict ..

Interactivity, Scalability and Resource control for

The conflict between resource consumption and query performance in the data mining context often has no satisfactory solution. This not only stands in sharp contrast to the need of the analysts for interactive response times, but also makes the seamless integration of data mining operators into common multiuser database systems a difficult and (so far) not very prosperous task. We believe that an efficient solution to the problems of database support for KDD has to affect the whole query processing from the data access on disk up to the complex data mining operators. The basic idea of our framework is to provide resource efficiency and interactivity through precise control over the order in which data is processed from the index structure through the whole query tree. It consists of an index that is basically an extension of the UB-Tree and allows to translate efficient data access patterns into various data orderings. Our KDD-algebra exploits these orderings to allow the control of resource consumption in each operator while providing interactive response times and pipelined query processing. This paper describes the framework and shows its benefits in preprocessing and in the parallel and interactive detection of outliers

Autonomy over Ubiquity: Coping with the Complexity of a Distributed World

Today's distributed database systems adhere to the principle of ubiquity such that all the information is everywhere available in an equitable fashion. This transparent data distribution leads to at least two severe problems. First, the complexity becomes unmanageable if one tries to impose a centralized control upon the computer model of the "real" world, that is naturally distributed. Second, if at all possible, the centralized control of ubiquity would be prohibitively expensive in terms of performance. We argue that the paradigm of ubiquity should be replaced by object autonomy in a distributed, persistent environment. The objects have built-in control over many important aspects that were previously controlled centrally: the life cycle, the cooperation control, and the distribution control. We describe the functionality of such an autonomous object model in metaphorical terms, concentrating on internal object aspects, inter-object communication and distributed infrastructure. We ..

Multi-Object Cooperation in Distributed Object Bases

It is an emerging trend to build large information systems in a component-based fashion where the components follow the concept of object. Applications are constructed by organizing pre-built objects such that they cooperate with each other to perform some task. However, considerable programming effort is required to express multi-object constraints in terms of the traditional message-passing mechanism. This observation lead many authors to suggest communication abstractions in object models. One promising approach is to separate multi-object constraints from the objects and collect them into a separate construct. We call this construct an alliance. Unlike other approaches we allow alliances to involve large sets of long-lived objects which may dynamically vary during the --- also potentially long --- life-time of the alliance. Alliances are not only visible at the specification level but are also computational entities which enforce multi-object constraints at run-time. They do so in..