106 research outputs found
Measuring rule-based LTLf process specifications: A probabilistic data-driven approach
No full textDeclarative process specifications define the behavior of processes by means of rules based on Linear Temporal Logic on Finite Traces
. In a mining context, these specifications are inferred from, and checked on, multi-sets of runs recorded by information systems (namely, event logs). To this end, being able to gauge the degree to which process data comply with a specification is key. However, existing mining and verification techniques analyze the rules in isolation, thereby disregarding their interplay. In this paper, we introduce a framework to devise probabilistic measures for declarative process specifications. Thereupon, we propose a technique that measures the degree of satisfaction of specifications over event logs. To assess our approach, we conduct an evaluation with real-world data, evidencing its applicability for diverse process mining tasks, including discovery, checking, and drift detection
Interestingness of traces in declarative process mining: The janus LTLPf Approach
No full textDeclarative process mining is the set of techniques aimed at extracting behavioural constraints from event logs. These constraints are inherently of a reactive nature, in that their activation restricts the occurrence of other activities. In this way, they are prone to the principle of ex falso quod libet: they can be satisfied even when not activated. As a consequence, constraints can be mined that are hardly interesting to users or even potentially misleading. In this paper, we build on the observation that users typically read and write temporal constraints as if-statements with an explicit indication of the activation condition. Our approach is called Janus, because it permits the specification and verification of reactive constraints that, upon activation, look forward into the future and backwards into the past of a trace. Reactive constraints are expressed using Linear-time Temporal Logic with Past on Finite Traces (LTLp f). To mine them out of event logs, we devise a time bi-directional valuation technique based on triplets of automata operating in an on-line fashion. Our solution proves efficient, being at most quadratic w.r.t. trace length, and effective in recognising interestingness of discovered constraints
Detection of statistically significant differences between process variants through declarative rules
No full textServices and products are often offered via the execution of processes that vary according to the context, requirements, or customisation needs. The analysis of such process variants can highlight differences in the service outcome or quality, leading to process adjustments and improvement. Research in the area of process mining has provided several methods for process variant analysis. However, very few of those account for a statistical significance analysis of their output. Moreover, those techniques detect differences at the level of process traces, single activities, or performance. In this paper, we aim at describing the distinctive behavioural characteristics between variants expressed in the form of declarative process rules. The contribution to the research area is two-pronged: the use of declarative rules for the explanation of the process variants and the statistical significance analysis of the outcome. We assess the proposed method by comparing its results to the most recent process variant analysis methods. Our results demonstrate not only that declarative rules reveal differences at an unprecedented level of expressiveness, but also that our method outperforms the state of the art in terms of execution time
Measuring the interestingness of temporal logic behavioral specifications in process mining
No full textThe assessment of behavioral rules with respect to a given dataset is key in several research areas, including declarative process mining, association rule mining, and specification mining. An assessment is required to check how well a set of discovered rules describes the input data, and to determine to what extent data complies with predefined rules. Particularly in declarative process mining, Support and Confidence are used most often, yet they are reportedly unable to provide a sufficiently rich feedback to users and cause rules representing coincidental behavior to be deemed as representative for the event logs. In addition, these measures are designed to work on a predefined set of rules, thus lacking generality and extensibility. In this paper, we address this research gap by developing a measurement framework for temporal rules based on (LTLp). The framework is suitable for any temporal rules expressed in a reactive form and for custom measures based on the probabilistic interpretation of such rules. We show that our framework can seamlessly adapt well-known measures of the association rule mining field to declarative process mining. Also, we test our software prototype implementing the framework on synthetic and real-world data, and investigate the properties characterizing those measures in the context of process analysis
Cronache tecniche di ingegneria dalla Toscana: "Adeguamento sismico di un edificio a due piani a Firenze: taglio di due pilastri centrali con messa in forza di rinforzo in acciaio" Progettista delle strutture: Prof. Ing. Paolo SPINELLI Collaborazione progetto strutturale: Dott. Ing. Alessio MARGIOTTA Direzione lavori: Dott. Ing. Massimiliano CECCONI
No full textAll’interno dei locali di un edificio esistente, situato a Firenze e costituito da due piani fuori terra, vi è stata l’esigenza di realizzare uno spazio atto ad ospitare conferenze, congressi e summit dei vertici dirigenziali dell’azienda: si doveva quindi realizzare un nuovo Auditorium a piano terra e i relativi locali dovevano essere riorganizzati in modo tale da rispondere alle nuove esigenze funzionali. Il maggior ostacolo da superare era rappresentato dalla presenza di due pilastri dell’edificio che risultavano incompatibili con le esigenze di visibilità e fruibilità della sala. D’altro canto la loro rimozione non era facile in quanto senza di essi si sarebbe avuta una luce libera di quasi 15 metri e per l’appunto essi appartenevano ad una campata che, oltre a portare il solaio di piano primo di luce 9.90 metri, si faceva carico anche delle travi di copertura aventi luce 20 m; Si è deciso di seguire la strada dell’eliminazione dei due pilastri e del conseguente rinforzo della campata con un’opportuna struttura in acciaio affiancata a quella in C.A. esistente
Robustness of the Sequential Efficient Design for Identifying a Target Subpopulation
No full textPrecision medicine is an innovative approach for tailoring treatments based on individual characteristics or biomarkers. Enrichment is a main strategy in the development of clinical trials for precision medicine as it “is the prospective use of any patient characteristic to select a study population in which detection of a drug effect (if one is, in fact, present) is more likely than it would be in an unselected population.” (FDA, 2019) [ 1]. Although a binary biomarker can be used to stratify the subjects, the situation is more complex if a continuous
biomarker is associated with patient responses. Recently Baldi Antognini et al. [ 2] provided the optimal allocations for inference on the threshold of a continuous biomarker and proposed a new Covariate-Adaptive
procedure, called the Sequential Efficient Design (SED), to implement these designs sequentially. In this paper we push forward the results by exploring the robustness of the SED under possible deviation from the
linearity assumption of the response-biomarker relationship, taking also into account comparisons with the permuted block design
Blockchain-based traceability of inter-organisational business processes
No full textBlockchain technology opens up new opportunities for Business Process Management. This is mainly due to its unprecedented capability to let transactions be automatically executed and recorded by Smart Contracts in multi-peer environments, in a decentralised fashion and without central authoritative players to govern the workflow. In this way, blockchains also provide traceability. Traceability of information plays a pivotal role particularly in those supply chains where multiple parties are involved and rigorous criteria must be fulfilled to lead to a successful outcome. In this paper, we investigate how to run a business process in the context of a supply chain on a blockchain infrastructure so as to provide full traceability of its run-time enactment. Our approach retrieves information to trace process instances execution solely from the transactions written on-chain. To do so, hash-codes are reverse-engineered based on the Solidity Smart Contract encoding of the generating process. We show the results of our investigation by means of an implemented software prototype, with a case study on the reportedly challenging context of the pharmaceutical supply chain
Finding non-compliances with declarative process constraints through semantic technologies
No full textBusiness process compliance checking enables organisations to assess whether their processes fulfil a given set of constraints, such as regulations, laws, or guidelines. Whilst many process analysts still rely on ad-hoc, often handcrafted per-case checks, a variety of constraint languages and approaches have been developed in recent years to provide automated compliance checking. A salient example is Declare, a well-established declarative process specification language based on temporal logics. Declare specifies the behaviour of processes through temporal rules that constrain the execution of tasks. So far, however, automated compliance checking approaches typically report compliance only at the aggregate level, using binary evaluations of constraints on execution traces. Consequently, their results lack granular information on violations and their context, which hampers auditability of process data for analytic and forensic purposes. To address this challenge, we propose a novel approach that leverages semantic technologies for compliance checking. Our approach proceeds in two stages. First, we translate Declare templates into statements in SHACL, a graph-based constraint language. Then, we evaluate the resulting constraints on the graph-based, semantic representation of process execution logs. We demonstrate the feasibility of our approach by testing its implementation on real-world event logs. Finally, we discuss its implications and future research directions
Stima della probabilità di degrado biologico su cappotti. Proposta di un metodo basato sulle reti neurali per la stima della probabilità di colonizzazione biologica su sistemi ETICS
No full textLAUREA MAGISTRAL
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