Maurizio Talamo

Process Mining Manifesto

Process mining techniques are able to extract knowledge from event logs commonly available in today’s information systems. These techniques provide new means to discover, monitor, and improve processes in a variety of application domains. There are two main drivers for the growing interest in process mining. On the one hand, more and more events are being recorded, thus, providing detailed information about the history of processes. On the other hand, there is a need to improve and support business processes in competitive and rapidly changing environments. This manifesto is created by the IEEE Task Force on Process Mining and aims to promote the topic of process mining. Moreover, by defining a set of guiding principles and listing important challenges, this manifesto hopes to serve as a guide for software developers, scientists, consultants, business managers, and end-users. The goal is to increase the maturity of process mining as a new tool to improve the (re)design, control, and support of operational business processes.

Abstract data types for the logical modeling of complex data

Abstract In this paper we propose a logical data model for complex data. Our proposal extends the relational model by using abstract data types for domains specification and an extended relational algebra is also introduced. The introduction of the parameterized type Geometry(S), where S is a ground set of elements, allows the representation of complex aggregated data. As an example, we discuss how our model supports the definition of geographical DBMSs. Moreover, to show the generality of our approach, we sketch how the model can be used in the framework of statistical applications.

A layered IT infrastructure for secure interoperability in personal data registry digital government services

In this paper we describe the architectural solution defined and implemented to ensure secure interoperability among information technology (IT) systems managing personal data registries in Italian municipalities and Ministry of Interior. The architecture features a clear separation between security services, provided at an infrastructure level, and application services, exposed on the Internet as Web services. This approach has allowed to easily design and implement secure interoperability, since - notwithstanding the huge variety of IT solutions deployed all over the Italian municipalities to manage personal data registries - existing application services have not required major changes to be able to interoperate.

Experiences and issues in the realization of e-government services

Certification of the executed service is a critical issue for an e-government infrastructure. In fact, given the legal value that is often attached to data managed and exchanged by public administrations, being able to document the actual execution of e-services is of the utmost importance. This is made more complex in cases, as often happens in the public administration sector, where e-services are based on legacy systems managed by autonomous and independent organizations. In this paper we discuss, starting from real-life e-government systems developed in Italy, the introduction, within the standard three tier architecture for e-services, of new control components, based on efficient algorithmic techniques, providing solutions for this issue.

Serving Requests with On-line Routing

In this paper we consider the on-line version of the routing problem with release times. Formally, it consists in a metric space M with a distinguished point o (the origin), plus a sequence of triples where pi is a point of M, ri specifies the first moment in which the request is ready to be served, and ti represents the moment in which the request is known. A server located at point o at time 0 that moves at constant unit speed must serve the sequence of requests trying to minimize the total time till all the requests are served.

Coherence maintainance in cooperative information systems: the access key warehouse approach

In this paper, we present and discuss a novel architectural approach supporting the integration among legacy information systems of autonomous organizations. It is based on the use of a data wareho...

Compact Implicit Representation of Graphs

How to represent a graph in memory is a fundamental data structuring problem. In the usual representations, a graph is stored by representing explicitly all vertices and all edges. The names (labels) assigned to vertices are used only to encode the edges and betray nothing about the structure of the graph itself and hence are a “waste” of space. In this context, we present a general framework for labeling any graph so that adjacency between any two given vertices can be tested in constant time. The labeling schema assigns to each vertex x of a general graph a O(δ(x)log3n) bit label, where n is the number of vertices and δ(x) is x’s degree. The adjacency test can be performed in 5 steps and the schema can be computed in polynomial time. This representation strictly contrasts with usual representations, i.e. adjacency matrix and adjacency list representations, which require O(nlog n) bit label per vertex and constant time adjacency test, and O(δ(x)log n) bit label per vertex and O(logδ (x)) steps to test adjacency, respectively. Additionally, the labeling schema is implicit, that is: no pointers are used.

A CONVEX HULL ALGORITHM FOR POINTS WITH APPROXIMATELY KNOWN POSITIONS

We consider the problem of deriving good approximations of the convex hull of a set of points in the plane in the realistic case that only arbitrary finite approximations of the real valued coordinates can be known. In particular, the algorithm we introduce derives sequences of improved certified approximations converging to the exact solution, at the same time allowing the insertion of new points to the problem instance. The complexity analysis of the algorithm is performed by referring to a suitable computation model, based on a RAM with logarithmic costs, and the derived space and time bounds are shown to be competitive with respect to current off-line algorithms.

On locally presented posets (note)

Abstract In this paper, the concept of local presentability of posets is introduced, together with the related notion of boolean dimension, as an extension of the classic Dushnik-Miller dimension. Such a concept seems to represent a powerful tool for the efficient encoding of poset and transitive closure of dags, from the point of view of both space and time complexity. Encodings of some classes of posets are presented as an application of the theory: in particular, an efficient encoding of a subclass of the class of planar dags is introduced.

An Efficient Data Structure for Lattice Operations

In this paper, we consider the representation and management of an element set on which a lattice partial order relation is defined. In particular, let n be the element set size. We present an \nradn-space implicit data structure for performing the following set of basic operations: 1. Test the presence of an order relation between two given elements, in constant time. 2. Find a path between two elements whenever one exists, in O(l) steps, where l is the path length. 3. Compute the successors and/or predecessors set of a given element, in O(h) steps, where h is the size of the returned set. 4. Given two elements, find all elements between them, in time O(k log d), where k is the size of the returned set and d is the maximum in-degree or out-degree in the transitive reduction of the order relation. 5. Given two elements, find the least common ancestor and/or the greatest common successor in