UML Stereotypes Research Articles

UEWDM NAVIGATIONAL DESIGN: A CASE STUDY OF APU WEB ATTENDANCE

The process of designing web application has become a challenge for many individuals, specifically web developers due to interaction processes involvement in the design process. The designs should incorporate conceptual aspect, interaction processes, navigation structures and abstract presentation design. Unfortunately, many practitioners believe that most of the web applications have been developed in an ad hoc manner and less focus on the interaction processes. As a solution, UEWDM has been proposed in order to deal with the issues mentioned above. Thus, in this paper, APU web attendance is presented as a case study of UEWDM in order to verify that the proposed design model is applicable to any web application design with interaction processes. Research’s contribution relies on the expressive web design model of navigational design, which utilizes UML stereotypes for the interaction processes modeling. In other words, UEWDM could act as a guideline and assist web designers in designing web applications that consist of interaction processes.

Using empirical studies to mitigate symbol overload in iStar extensions

Modelling languages are frequently extended to include new constructs to be used together with the original syntax. New constructs may be proposed by adding textual information, such as UML stereotypes, or by creating new graphical representations. Thus, these new symbols need to be expressive and proposed in a careful way to increase the extension’s adoption. A method to create symbols for the original constructs of a modelling language was proposed and has been used to create the symbols when a new modelling language is designed. We argue this method can be used to recommend new symbols for the extension’s constructs. However, it is necessary to make some adjustments since the new symbols will be used with the existing constructs of the modelling language original syntax. In this paper, we analyse the usage of this adapted method to propose symbols to mitigate the occurrence of overloaded symbols in the existing iStar extensions. We analysed the existing iStar extensions in an SLR and identified the occurrence of symbol overload among the existing constructs. We identified a set of fifteen overloaded symbols in existing iStar extensions. We used these concepts with symbol overload in a multi-stage experiment that involved users in the visual notation design process. The study involved 262 participants, and its results revealed that most of the new graphical representations were better than those proposed by the extensions, with regard to semantic transparency. Thus, the new representations can be used to mitigate this kind of conflict in iStar extensions. Our results suggest that next extension efforts should consider user-generated notation design techniques in order to increase the semantic transparency.

Enterprise architecture evaluation using architecture framework and UML stereotypes

Article history: Received January 28, 2014 Received in revised format 5 May 2014 Accepted 4 July 2014 Available online July 6 2014 There is an increasing need for enterprise architecture in numerous organizations with complicated systems with various processes. Support for information technology, organizational units whose elements maintain complex relationships increases. Enterprise architecture is so effective that its non-use in organizations is regarded as their institutional inability in efficient information technology management. The enterprise architecture process generally consists of three phases including strategic programing of information technology, enterprise architecture programing and enterprise architecture implementation. Each phase must be implemented sequentially and one single flaw in each phase may result in a flaw in the whole architecture and, consequently, in extra costs and time. If a model is mapped for the issue and then it is evaluated before enterprise architecture implementation in the second phase, the possible flaws in implementation process are prevented. In this study, the processes of enterprise architecture are illustrated through UML diagrams, and the architecture is evaluated in programming phase through transforming the UML diagrams to Petri nets. The results indicate that the high costs of the implementation phase will be reduced. © 2014 Growing Science Ltd. All rights reserved.

Buddy System: Available, Consistent, Durable Web Service Transactions

In this paper we investigate the problem of providing consistency, availability and durability for web service transactions. We propose an approach that matches the availability of the popular lazy replica update propagation method while increases the durability and consistency. Our replica update propagation method is called the Buddy System, which requires that updates are preserved synchronously in two replicas. Our first implementation schedules fine-grained WS transactions. In these transactions each activity is a low level database operation. Later we consider each transaction as a black box, with only the corresponding metadata, expressed as UML specifications, as transaction semantics. We refer to these WS transactions as coarse-grained WS transactions. The Buddy System is able to handle these course grained WS transactions, using UML stereotypes that allow scheduling semantics to be embedded into the design model. We show that our approach guarantees one-copy serializability, matches the performance of the lazy update propagation methods, and increases durability in the presence of hardware failures.

UML design pattern metamodel‐level constraints for the maintenance of software evolution

SUMMARYSoftware maintenance including design is difficult because it is usually performed on someone else's work over a period of time. Maintaining a pattern‐based design is especially much more difficult when the information on specific patterns that have been used are not available in the corresponding design documents. Also, finding a maintainer who has a similar level of knowledge on specific patterns that the initial designer had is not easy. Pattern‐based design, the use of design patterns during the software design process, has become widely used in the object‐oriented community because of its many benefits such as its reuse. However, the defects in pattern‐based design can be introduced during the design maintenance phase when the changes are made to the requirements and the initial design, but the conformance to the original patterns is neglected. This conformance process is laborious and time consuming; no systematic process exists to guide the defects discovery and maintenance. Also, deep and correct knowledge of design patterns and their characteristics are required because this process is conducted by human experts. Failure to follow this conformance process and to maintain correct designs during software design evolution may cause serious problems in later software development and maintenance stages by not providing the benefits of pattern‐based design that would have been possible if followed correctly. There is a strong need of a systematic design and maintenance method for preventing defects in design patterns introduced during the evolution of pattern‐based software design and its maintenance. Because conventional UML design methods do not provide such systematic ways of assessing pattern‐based design conformance to the evolutionary changes, we have developed the pattern instance changes with UML profiles (PICUP) design method, which is an improved design method for perfective and corrective UML pattern‐based design maintenance and assessment. Design pattern in UML profiles (DPUP) is developed for the use of instantiation, maintenance, and assessment of UML pattern‐based designs to support the formal specification of a design pattern. DPUPs, as the main part of the PICUP design method, provide metamodel‐level UML design constraints using UML stereotype notations and metamodel‐level Object Constraint Language design constraints. Assessment of pattern‐based designs in UML class diagram with the corresponding DPUPs enforces maintainers to make necessary and correct changes to keep the principles of the original designs. Pattern‐related information is annotated using stereotype notations to help assess pattern‐based designs when changes are made. Furthermore, the structural conformance checking of a given UML pattern‐based design can be automated by using the assessment tool. The major contributions of this paper are: (i) specifying design patterns using extended UML profile; (ii) providing a means of how to instantiate pattern‐based designs from DPUPs with naming conventions; and (iii) providing design constraints for maintaining pattern‐based design to guide correct changes of a given design in PICUP method. Explanatory type case studies were performed to better understand and evaluate the effectiveness of the PICUP design method with DPUPs. Answers to the case study questionnaires and the pattern defects discovered from the case studies support the hypothesis that the PICUP method is an improved design method that ensures structural conformance of UML pattern‐based designs to the corresponding design patterns during perfective and corrective design maintenance for software systems. Copyright © 2011 John Wiley & Sons, Ltd.

How Developers' Experience and Ability Influence Web Application Comprehension Tasks Supported by UML Stereotypes: A Series of Four Experiments

In recent years, several design notations have been proposed to model domain-specific applications or reference architectures. In particular, Conallen has proposed the UML Web Application Extension (WAE): a UML extension to model Web applications. The aim of our empirical investigation is to test whether the usage of the Conallen notation supports comprehension and maintenance activities with significant benefits, and whether such benefits depend on developers ability and experience. This paper reports and discusses the results of a series of four experiments performed in different locations and with subjects possessing different experience-namely, undergraduate students, graduate students, and research associates-and different ability levels. The experiments aim at comparing performances of subjects in comprehension tasks where they have the source code complemented either by standard UML diagrams or by diagrams stereotyped using the Conallen notation. Results indicate that, although, in general, it is not possible to observe any significant benefit associated with the usage of stereotyped diagrams, the availability of stereotypes reduces the gap between subjects with low skill or experience and highly skilled or experienced subjects. Results suggest that organizations employing developers with low experience can achieve a significant performance improvement by adopting stereotyped UML diagrams for Web applications.

Metamodelling of production systems process models using UML stereotypes

This paper contributes to a formal framework for the automation of production systems. Automatic control systems deal currently with theoretical modelling techniques that aim to formally define the behaviour of a control system when process behaviours and system requirements are well defined. Our approach aims to facilitate a common and consensual understanding of an automated system at the early stage of a systems engineering process. This approach is based on the use UML stereotypes, based on a systemic approach, to globally formalise a production system satisfying the following predicate: Control Systems Requirements ∧ Process Systems Requirements ⇒ Production System Requirements.

Systematic stereotype usage

As one of the UML's main extension mechanisms, stereotypes play a crucial role in the UML's ability to serve a wide and growing base of users. However, the precise meaning of stereotypes and their intended mode of use has never been entirely clear and has even generated significant debate among experts. Two basic ways of using UML stereotypes have been observed in practice: One to support the classification of classes as a means of emulating metamodel extensions, the other to support the classification of objects as a means of assigning them certain properties. In this paper we analyze these two recognized stereotype usage scenarios and explain the rationale for explicitly identifying a third form of usage scenario. We propose some notational concepts which could be used to explicitly distinguish the three usage scenarios and provide heuristics as to when each should be used. Finally, we conclude by proposing enhancements to the UML which could support all three forms cleanly and concisely.

Deadlock detection in distribution object systems

The behaviour of a distributed system is largely determined by the use of synchronization primitives and threading policies of the underlying middleware. The inherent parallel nature of distributed systems may cause liveness problems, such as deadlocks and livelocks. An increasing number of distributed systems is built using object middleware. We exploit the fact that modern object middleware offers only a few built-in synchronization and threading primitives by suggesting UML stereotypes to represent each of these primitives in distributed object design. We define the semantics of the stereotypes using a process algebra. We use that semantics to translate UML diagrams into behaviourally equivalent process algebra representations and can then use model checking techniques to find potential deadlocks. The paper also shows how the model checking results can be related back to the original UML diagrams.