A5009122904- Semantic Web and Ontologies
- Advanced Database Systems and Queries
- Service-Oriented Architecture and Web Services
- Logic, Reasoning, and Knowledge
- Data Quality and Management
- Business Process Modeling and Analysis
- Data Management and Algorithms
- Natural Language Processing Techniques
- Distributed systems and fault tolerance
- AI-based Problem Solving and Planning
- Big Data and Business Intelligence
- Cloud Data Security Solutions
- Constraint Satisfaction and Optimization
- Rough Sets and Fuzzy Logic
- Scientific Computing and Data Management
- Graph Theory and Algorithms
- Advanced Graph Neural Networks
- Topic Modeling
- Welding Techniques and Residual Stresses
- Model-Driven Software Engineering Techniques
- Distributed and Parallel Computing Systems
- Cloud Computing and Resource Management
- IoT and Edge/Fog Computing
- Neutropenia and Cancer Infections
- Advanced Algebra and Logic
Free University of Bozen-Bolzano
2012-2023
Property graphs have reached a high level of maturity, witnessed by multiple robust graph database systems as well the ongoing ISO standardization effort aiming at creating new standard Graph Query Language (GQL). Yet, despite documented demand, schema support is limited both in existing and first version GQL Standard. It anticipated that second Standard will include rich DDL. Aiming to inspire development enhance capabilities systems, we propose PG-Schema, simple yet powerful formalism for...
Graphs have emerged as an important foundation for a variety of applications, including capturing and reasoning over factual knowledge, semantic data integration, social networks, providing knowledge machine learning algorithms. To formalise certain properties the to ensure quality, there is need describe schema such graphs. Because breadth applications availability different models, RDF property graphs, both Semantic Web database community independently developed graph languages: SHACL,...
We report on a community effort between industry and academia to shape the future of property graph constraints. The standardization for query language is currently underway through ISO Graph Query Language (GQL) project. Our position that this project should pay close attention schemas constraints, focus next key main purposes keys are enforcing data integrity allowing referencing identifying objects. Motivated by use cases from our partners, we argue constraints be able have different...
SHACL (SHape Constraint Language) is a W3C recommendation for validating graph-based data against set of constraints (called shapes). Importantly, allows to define recursive shapes, i.e. shape may refer itself, directly indirectly. The left open the semantics but proposals have emerged recently extend official support recursion. These are based on principle possibility (or non-contradiction): graph considered valid schema if one can assign shapes nodes in such way that all satisfied. This...
Rule-based diagnostics of power generating equipment is an important task in industry. In this demo we present how semantic technologies can enhance diagnostics. particular, our rule language sigRL that inspired by the real diagnostic languages Siemens. SigRL allows to write compact yet powerful programs relying on a high level data independent vocabulary, ontologies, and queries over these ontologies. We system SemDia. The attendees will be able SemDia using 50 Siemens turbines. also such...
Automatic knowledge graph (KG) construction is widely used for e.g. data integration, question answering and semantic search. There are many approaches of automatic KG construction. Among which, an important approach to map the raw a given domain schema, e.g., ontology or conceptual graph, construct entities properties according schema. However, existing KGs not always efficient enough resulting sufficiently application user-friendly. The main challenge arises from trade-off: schema should...
MAGIK demonstrates how to use meta-information about the completeness of a database assess quality answers returned by query. The system holds so-called table-completeness (TC) statements, which one can express that table is partially complete, is, it contains all facts some aspect domain.
We present a system that computes for query may be incomplete, complete approximations from above and below. assume setting where queries are posed over partially database, is, database is generally but known to contain information about specific aspects of its application domain. Which parts complete, described by set so-called table-completeness statements. Previous work led theoretical framework an implementation allowed one determine whether in such scenario given conjunctive guaranteed...
Data completeness is commonly regarded as one of the key aspects data quality. With this paper we make two main contributions: (i) develop techniques to reason about a query answer over partially complete database, taking into account constraints that hold and (ii) implement them by an encoding logic programming paradigms. As consider primary foreign keys well finite domain constraints. In way can identify more situations in which than was possible with previous work. For each combination...
Data analytics including machine learning is essential to extract insights from production data in modern industries. Visual for e.g., presenting the provide an instinctive perception exploratory analysis, facilitating presentation of analysis results and subsequent discussion on that. should allow a transparent common ground between experts projects, given multidisciplinary background these experts. However, standarised formalised way describing knowledge practice visualisation still...
This paper studies the completeness of conjunctive queries over a partially complete database and approximation incomplete queries. Given query set rules (a special kind tuple generating dependencies) that specify which parts are complete, we investigate whether can be fully answered, as if all data were available. If not, explore reformulating into either Maximal Complete Specializations (MCSs) or (unique up to equivalence) Minimal Generalization (MCG) is, best approximations from below...
Organizations continuously accumulate data, often according to some business processes. If one poses a query over such data for decision support, it is important know whether the stable, that is, answers will stay same or may change in future because processes add further data. We investigate stability conjunctive queries. To this end, we define formalism combines an explicit representation of control flow process with specification how read and inserted into database. consider different...