Antonio Vallecillo

• University of Malaga

Digital twins are increasingly used across a wide range of industries. Modeling is a key to digital twin development—both when considering the models which a digital twin maintains of its real‐world complement (“models in digital twin”) and when considering models of the digital twin as a complex (software) system itself. Thus, systematic developme...

Uncertainty is an inherent property of any complex system, especially those that incorporate physical parts or operate in real environments. In this paper, we focus on the Digital Twins of adaptive systems, which are particularly complex to design, verify, and optimize. One of the problems of having two systems (the physical one and its digital rep...

The classification of police reports according to the typification of the criminal act described in them is not an easy task. The reports are written in natural language and often present missing, imprecise, or even inconsistent information, or lack sufficient details to make a clear decision. Focusing on property crimes, the aim of this work is to...

Despite considerable research efforts on handling uncertainty in self-adaptive systems, a comprehensive understanding of the precise nature of uncertainty is still lacking. This paper summarises the findings of the 2023 Bertinoro Seminar on Uncertainty in Self- Adaptive Systems, which aimed at thoroughly investigating the notion of uncertainty, and...

Data-intensive applications aim at discovering valuable knowledge from large amounts of data coming from real-world sources. Typically, workflow languages are used to specify these applications, and their associated engines enable the execution of the specifications. However, as these applications become commonplace, new challenges arise. Existing...

Most experts agree that large language models (LLMs), such as those used by Copilot and ChatGPT, are expected to revolutionize the way in which software is developed. Many papers are currently devoted to analyzing the potential advantages and limitations of these generative AI models for writing code. However, the analysis of the current state of L...

Adaptive systems manage and regulate the behavior of devices or other systems using control loops to automatically adjust the value of some measured variables to equal the value of a desired set-point. These systems normally interact with physical parts or operate in physical environments, where uncertainty is unavoidable. Traditional approaches to...

The problem of mitigating uncertainty in self-adaptation has driven much of the research proposed in the area of software engineering for self-adaptive systems in the last decade. Although many solutions have already been proposed, most of them tend to tackle specific types, sources, and dimensions of uncertainty (e.g., in goals, resources, adaptat...

Software modeling started as a paradigm to help developers build better software faster by enabling them to specify, reason and manipulate software systems at a higher-abstraction level while ignoring irrelevant low-level technical details. But this same principle manifests in any other domain that has to deal with complex systems, software-based o...

There are numerous domains in which information systems need to deal with uncertain information. These uncertainties may originate from different reasons such as vagueness, imprecision, incompleteness or inconsistencies; and, in many cases, they cannot be neglected. In this paper, we are interested in representing and processing uncertain informati...

Software-intensive systems are increasingly used to support tasks that are typically characterized by high degrees of uncertainty. The modeling notations employed to design, verify, and operate such systems have increasingly started to capture different types of uncertainty, so that they can be explicitly considered when systems are developed and d...

Querying large models efficiently often imposes high demands on system resources such as memory, processing time, disk access or network latency. The situation becomes more complicated when data are highly interconnected, e.g. in the form of graph structures, and when data sources are heterogeneous, partly coming from dynamic systems and partly sto...

This paper provides a comprehensive overview and analysis of research work on how uncertainty is currently represented in software models. The survey presents the definitions and current research status of different proposals for addressing uncertainty modeling and introduces a classification framework that allows to compare and classify existing p...

Data preprocessing is known to be essential to produce accurate data from which mining methods are able to extract valuable knowledge. When data constantly arrives from one or more sources, preprocessing techniques need to be adapted to efficiently handle these data streams. To help domain experts to define and execute preprocessing tasks for data...

Context: Managing Non-Functional Requirements (NFRs) in software projects is challenging, and projects that adopt Model-Driven Development (MDD) are no exception. Although several methods and techniques have been proposed to face this challenge, there is still little evidence on how NFRs are handled in MDD by practitioners. Knowing more about the s...

Business rules specify the required or desirable states of affairs or behavior of IT systems, and typically involve deontic constraints that must be adequately specified to enable their appropriate representation and effective analysis. Such deontic constraints focus on the permitted actions and obligations of the agents to carry them out. In this...

The correct representation of the relevant properties of a system is an essential requirement for the effective use and wide adoption of model-based practices in industry. Uncertainty is one of the inherent properties of any measurement or estimation that is obtained in any physical setting; as such, it must be considered when modeling software sys...

Although model transformations are considered to be the heart and soul of Model Driven Engineering (MDE), there are still several challenges that need to be addressed to unleash their full potential in industrial settings. Among other shortcomings, their performance and scalability remain unsatisfactory for dealing with large models, making their w...

The logic of the UML and OCL modeling languages is based on crisp values, e.g., true or false. However, when modeling systems that work in physical environments or where human actors are involved, different users may have subjective opinions about the reality that they perceive, and thus may need to assign different levels of confidence to the logi...

Although Model-Based Software Engineering (MBE) is a widely accepted Software Engineering (SE) discipline, no agreed-upon core set of concepts and practices (i.e., a Body of Knowledge) has been defined for it yet. With the goals of characterizing the contents of the MBE discipline, promoting a global consistent view of it, clarifying its scope with...

Complex Event Processing (CEP) is a powerful technology for analyzing streams of real-time events, coming from different sources, and for extracting conclusions from them. In many situations, these events are not free from uncertainty, due to either unreliable data sources and networks, measurement uncertainty, or to the inability to determine whet...

Context: An essential requirement for the design and development of any engineering application that deals with real-world physical systems is the formal representation and processing of physical quantities, comprising both measurement uncertainty and units. Although solutions exist for several programming languages and simulation frameworks, this...

Complex Event Processing (CEP) is a powerful technology in realtime distributed environments for analyzing fast and distributed streams of data, and deriving conclusions from them. CEP permits defining complex events based on the events produced by the incoming sources in order to identify complex meaningful circumstances and to respond to them as...

The expression and management of uncertainty, both in the information and in the operations that manipulate it, is a critical issue in those systems that work with physical environments. Measurement uncertainty can be due to several factors, such as unreliable data sources, tolerance in the measurements, or the inability to determine if a certain e...

Understanding the experiences of instructors teaching modelling and model-driven engineering is of great relevance to determining how MDE courses should be managed in terms of content, assessment, and teaching methods. In this paper, we report the results of a survey of 47 instructors in this field. Questions address course content, tools and techn...

Model-based Software Engineering (MBSE) is now accepted as a Software Engineering (SE) discipline and is being taught as part of more general SE curricula. However, an agreed core of concepts, mechanisms and practices --- which constitutes the Body of Knowledge of a discipline --- has not been captured anywhere, and is only partially covered by the...

This paper proposes the use of equivalence partitioning techniques for testing models and model transformations. In particular, we introduce the concept of classifying terms, which are general OCL terms on a class model enriched with OCL constraints. Classifying terms permit defining equivalence classes, in particular for partitioning the source an...

Uncertainty is an inherent property of any measure or estimation performed in any physical setting, and therefore it needs to be considered when modeling systems that manage real data. Although several modeling languages permit the representation of measurement uncertainty for describing certain system attributes, these aspects are not normally inc...

One of the challenges of modeling any software application that deals with real-world physical systems resides in the correct representation of numerical values and their units. This paper shows how both measurement uncertainty and units can be effectively incorporated into software models, becoming part of their basic type systems, and illustrates...

A critical issue in the Web of Things (WoT) is the need to process and analyze the interactions of Web-interconnected real-world objects. Complex Event Processing (CEP) is a powerful technology for analyzing streams of information about real-time distributed events, coming from different sources, and for extracting conclusions from them. However, i...

Complex Event Processing (CEP) is a cutting-edge technology for analyzing and correlating streams of information about events that happen in a system, and deriving conclusions from them. CEP permits defining complex events based on the events produced by the incoming sources, to identify complex meaningful circumstances and to respond to them as qu...

Models are expanding their use for many different purposes in the field of software engineering and, due to their importance, universities have started incorporating modeling courses into their programs. Being a relatively new discipline, teaching modeling concepts brings in new challenges. Our contribution in this paper is threefold. First, we lis...

This paper reports on the panel session of the 17th Workshop in OCL and Textual Modeling, As in previous years, the panel session featured several lightning talks for presenting recent developments and open questions in the area of OCL and textual modeling. During this session, the OCL community discussed, stimulated through short pre- sentations b...

Testing the correctness of the specification of a model transformation can be as hard as testing the model transformation itself. Besides, this test has to wait until at least one implementation is available. In this paper we explore the use of tracts and classifying terms to test the correctness of a model transformation specification (a transform...

This book constitutes the proceedings of the 15th International Conference on Service-Oriented Computing, ICSOC 2017, held in malaga, Spain, in November 2017. The 33 full papers presented together with 20 short papers and 4 keynotes in this volume were carefully reviewed and selected from 179 submissions. The selected papers cover a wide variety of...

Modelling and Simulation approaches use system models to conduct simulation experiments. Experimental frames have been applied in this context to formally define a system's context. During the creation of an experimental frame for a simple spring model it becomes clear that experimental frames in their current definition lack certain properties and...

Although several software modeling languages permit the representation of key aspects of physical entities, such as units, precision or measurement uncertainty, these aspects are not typically incorporated into their type systems. Therefore, operating with such properties is normally cumbersome and contrived. This paper shows how both data uncertai...

This paper explores the use of table-based representation for artifacts occurring in model-driven development as opposed to graph-based representation. As an example for table-based representation of models, we explain how views on object interaction that are traditionally represented as UML sequence or communication diagrams can be realized by spr...

Context The performance and scalability of model transformations is gaining interest as industry is progressively adopting model-driven techniques and multicore computers are becoming commonplace. However, existing model transformation engines are mostly based on sequential and in-memory execution strategies, and thus their capabilities to transfor...

This chapter is dedicated to discussing the engineering aspects involved in the integration of modeling languages, as an essential part of the globalization process. It covers the foundations of language integration, the definition of the relationships between the languages to be integrated, and the various dimensions of language and tool integrati...

As the size and complexity of models grow, there is a need to count on novel mechanisms and tools for transforming them. This is required, e.g., when model transformations need to provide target models without having access to the complete source models or in really short time-as it happens, e.g., with streaming models-or with very large models for...

Model-Driven Development (MDD) is no longer a novel development paradigm. It has become mature from a research perspective and recent studies show its adoption in industry. Still, some issues remain a challenge. Among them, we are interested in the treatment of non-functional requirements (NFRs) in MDD processes. Very few MDD approaches have been r...

As software systems have grown large and complex in the last few years, the problems with which Model-Driven Development has to cope have increased at the same pace. In particular, the need to improve the performance and scalability of model transformations has become a critical issue. In previous work we introduced LinTra, a model transformation p...

As the complexity of model transformations grows, there is an increasing need to count on methods, mechanisms, and tools for checking their correctness, i.e., the alignment between specifications and implementations. In this paper we present a light-weight and static approach for locating the faulty rules in model transformations, based on matching...

Model Driven Engineering (MDE) is an approach to software development where models play a central role in all software engineering processes. Conceived to provide significant gains in productivity, portability, maintainability and interoperability, MDE is now starting to be effectively used in industry. Thus, companies are beginning to evaluate the...

Model transformations dealing with very large models need to count on mechanisms and tools to be able to manage them. The usual approach to improve performance in these cases has focused on the use of concurrency and parallelization techniques, which aim at producing the correct output model(s). In this paper we present our initial approach to prod...

Queuing Network Models (QNMs) provide powerful notations and tools for modeling and analyzing the performance of many different kinds of systems. Although several powerful tools currently exist for solving QNMs, some of these tools define their own model representations, have been developed in platform-specific ways, and are normally difficult to e...

This paper introduces the Special Issue on Component-Based Software Engineering and Software Architecture, which contains extended versions of a selection of the best papers presented at the CompArch 2012 conference, held in June 2012, in Bertinoro, Italy.

The problems addressed byModel-Driven Engineering (MDE) approaches are increasingly complex, hence performance and scalability of model transformations are gaining importance. In previous work, we introduced LinTra, which is a platform for executing out-place model transformations in parallel. The parallel execution of LinTra is based on the Linda...

The modular specification of non-functional properties of systems is a current challenge of Software Engineering, for which no clear solution exists. However, in the case of Domain-Specific Languages some successful proposals are starting to emerge, combining model-driven techniques with aspect-weaving mechanisms. In this paper we show one of these...

Nowadays, model transformations languages and engines use a sequential execution model. This is, only one execution thread deals with the whole transformation. However, model transformations dealing with very large models, such as those used in biology or aerospace applications, require concurrent solutions in order to speed up their performance. I...

The ODP Enterprise Language is used to describe the organizational objectives and policies that apply to some system to be specified. It also captures constraints associated with the environment in which the system is to be used. Because the enterprise specification is concerned more with organizational issues than technical details of the system,...

This paper provides an editorial introduction to the current special issue on Open Distributed Processing. It looks back over the development of the ODP standards and at the way in which they have been used, and looks forward at the way current activities are progressing. It contains a broad bibliography covering ODP standards, related research wor...

As the complexity of open distributed systems grows, the need to rely on concepts and notations for expressing and structuring their specifications becomes essential. However, having concepts and notations is not enough. The large size and complexity of the set of models that constitute the system specifications also forces the need to have tools f...

Cloud computing promises easy access, low entry cost and elasticity. However, elastic service provisioning is usually delivered via service replication, which must be supervised manually, hand-picking the services to replicate and ensuring their proper load balance. Automated service provisioning, i.e., the function of automatically scaling the ser...

IntroductionWith the common goal of producing higher quality systems at lower costs, model-driven engineering (MDE) is becoming an integral part of all areas and disciplines related to Software Engineering. Far from the initial role of (UML) models as mere sketches of the structure of software systems, models have become primary artefacts in most s...

ContextDomain-Specific Visual Languages (DSVLs) play a crucial role in Model-Driven Engineering (MDE). Most DSVLs already allow the specification of the structure and behavior of systems. However, there is also an increasing need to model, simulate and reason about their non-functional properties. In particular, QoS usage and management constraints...

Model transformations play an important role in Model-Driven Engineering (MDE), and as their size and complexity grow, there is an increasing need to count on tool support for testing their correctness. In this work, we present TractsTool, a tool for specifying and testing several different kinds of model transformations, e.g., model-to-model, mode...

A lo largo de la pasada década, la ingeniería del software basada en modelos (Model-Driven Engineering, MDE) ha surgido como un nuevo paso en el camino hacia una verdadera industrialización de la producción de software. Tras el éxito de la tecnología orientada a objetos, el uso sistemático de modelos se presenta ahora como la forma apropiada para c...

Several approaches for specifying the requirements for model transformations have been proposed. Most of them define constraints on source and target models as well as on the relationships between them. A major advantage of these approaches is their independence from transformation implementation languages and transformation implementations. Howeve...

In model-driven engineering (MDE), models constitute the central artifacts in the development process, and thus, are often built by teams of developers. As a consequence, adequate version control for models is crucial to the success of MDE-based projects. Several model versioning systems have been proposed recently. Most of them are generic in the...

Examples are of central concern in teaching modeling. Typically, the general principles and concepts that have to be communicated are explained in terms of smaller or larger modeling examples with the hope that the examples cover the central issues of the principles and concepts well. The paper discusses a classification catalogue for examples alon...

Reliability is an attribute that appears in all quality models, so it is important to take it into account when developing any kind of system. Its evaluation at latter stages of the software development may force the re-engineering of important parts of the system, something very costly. This is why it should be raised to the system design phase. A...

Software adaptation is becoming increasingly important as more and more applications need to dynamically adapt their structure and behavior to cope with changing contexts, available resources and user requirements. Maude is a high-performance reflective language and system, supporting both equational and rewriting logic specification and programmin...

In previous work we have presented an approach to monitor nonfunctional properties of systems modeled in terms of domain specific visual languages using observers. In this work we present an approach to decouple the definition of observers behavior and systems behavior. Having a library with different kinds of observers behavior, and having the beh...

The ODP Enterprise Language is used to describe the organizational objectives and policies that apply to the system to be specified. It also captures constraints associated with the environment in which the system is to be used. Because the enterprise specification is concerned more with organizational issues than technical details of the system, t...

In certain systems, software must be adapted at runtime to the requirements and changes occurring in the context. A strategy to achieve this goal is to model such systems as software architectures making use of the Component-based Software Engineering (CBSE). Thus, the system can be adapted through the reconfiguration of the software architectures....

Model-driven Web Engineering is an effective approach for improving the development of Web applications by providing appropriate abstraction mechanisms and different viewpoints. However, maintaining existing Web models still presents some significant research challenges. In particular, maintenance and evolution tasks are based on fine-grained atomi...

Multi-viewpoint modeling is an effective technique to deal with the ever-growing complexity of large-scale systems. The evolution ofmulti-viewpoint system specifications is currently accomplished in terms of fine-grained atomic changes. Apart from being a very low-level and cumbersome strategy, it is also quite unnatural to system modelers, who thi...

As the complexity of MDE artefacts grows, there is an increasing need to rely on precise and abstract mechanisms that allow system architects to reason about the systems they design, and to test their individual components. In particular, assigning types to models and model transformations is needed for realizing many key MDE activities. This paper...

Model-driven engineering (MDE) already plays a key role in Human-Computer Interaction for the automatic generation of end-user interfaces from their abstract and platform-independent specifications. Moreover, MDE techniques and tools are proving to be very useful for adapting at runtime the final user interfaces according to the current context pro...

The need to select a component among a set of possible candidates that offer similar functionality opens the need to count with objective methods that help developers in this difficult task. One necessary step is to define a set of metrics that offer useful and simple results for the component selection process. In this position paper we present a...

Although Model Driven Software Development (MDSD) is achieving significant progress, it is still far from becoming a real Engineering discipline. In fact, many of the difficult problems of the engineering of complex software systems are still unresolved, or simplistically addressed by many of the existing MDSD approaches. In this paper we outline t...

In this paper we present some of the key issues involved in model transformation specification and testing, discuss and classify some of the existing approaches, and introduce the concept of Tract, a generalization of model transformation contracts. We show how Tracts can be used for model transformation specification and black-box testing, and the...