Learning Linear Temporal Properties

We present two novel algorithms for learning formulas in Linear Temporal Logic (LTL) from examples. The first learning algorithm reduces the learning task to a series of satisfiability problems in propositional Boolean logic and produces a smallest LTL formula (in terms of the number of subformulas) that is consistent with the given data. Our second learning algorithm, on the other hand, combines the SAT-based learning algorithm with classical algorithms for learning decision trees. The result is a learning algorithm that scales to real-world scenarios with hundreds of examples, but can no longer guarantee to produce minimal consistent LTL formulas. We compare both learning algorithms and demonstrate their performance on a wide range of synthetic benchmarks. Additionally, we illustrate their usefulness on the task of understanding executions of a leader election protocol

Minors and resolutions of non-commutative schemes

In this article we develop the theory of minors of non-commutative schemes. This study is motivated by applications in the theory of non-commutative resolutions of singularities of commutative schemes. In particular, we construct a categorical resolution for non-commutative curves and in the rational case show that it can be realized as the derived category of a quasi-hereditary algebra.Comment: 31 pages, revised and extended versio

Singular curves and quasi-hereditary algebras

In this article we construct a categorical resolution of singularities of an excellent reduced curve $X$, introducing a certain sheaf of orders on $X$. This categorical resolution is shown to be a recollement of the derived category of coherent sheaves on the normalization of $X$ and the derived category of finite length modules over a certain artinian quasi-hereditary ring $Q$ depending purely on the local singularity types of $X$. Using this technique, we prove several statements on the Rouquier dimension of the derived category of coherent sheaves on $X$. Moreover, in the case $X$ is rational and projective we construct a finite dimensional quasi-hereditary algebra $\Lambda$ such that the triangulated category of perfect complexes on $X$ embeds into $D^b(\Lambda-\mathsf{mod})$ as a full subcategory.Comment: minor changes; to appear in IMR

Media Literacy and News Libraries in Croatia and their Importance for Digital Age Journalism and Reporting

Every day newspaper industry in Croatia produces a great quantity of newspaper articles which are not sufficiently searchable and not easily accessible. It has a negative effect on the quality of news reporting. On the other hand newspapers report on daily events and are a source of information for users. Proper functioning of news libraries is of great importance for print journalists. The present practice of the newspaper industry in Croatia in the segment of newspaper documentation shows that the need for news librarians has not been recognized, that is, they have not been sufficiently involved. By using organized data bases journalists and researchers would spend less time searching newspapers and collecting newspaper articles and would therefore have more time to spend on writing articles and checking information. As a consequence the quality of newspapers would improve. The subject of this paper is media literacy in relation to the meaning of functioning of news libraries in Croatia. How should journalists develop their media literacy to be able to understand the importance of news libraries and newspaper archives in order to be able to use them more efficiently? How could they more easily access a news library and be able to better value and analyze the collected newspaper articles and other data prepared by the mentioned service? On the other hand, because of the new technological demands and greater possibilities of application of information technologies news librarians are expected to be media literate and in this way become active partners to journalists. To which extend would greater standardization and efficient digitization facilitate the search for and access to information? How could a better understanding of the importance of news library service start some positive changes in print journalism? The present situation in news libraries in Croatia shows that there is a need for better search possibilities of the past period. The newspapers from the period of Homeland War and the transition period are especially important to Croatian journalists and researchers. The print media journalists need professional help of news librarians when searching for and checking information especially from the nondigitized period

Ispitivanje oksido – redukcijskih svojstava ((1E)-1-N-{[4-(4-{[(E)-N-(2-aminofenil) karboksiimidoil] fenoksi}butoksi)fenil]metiliden}benzen-1,2-diamina uporabom cikličke voltametrije

U ovome radu opisana je uporaba cikličke voltametrije u svrhu ispitivanja oksidoredukcijskih svojstava novosintetizirane Schiffove baze ((1E)-1-N-{[4-(4-{[(E)-N-(2-aminofenil) karboksiimidoil] fenoksi} butoksi) fenil] metiliden} benzen- 1,2 –diamin, S36. Snimanjem cikličkih voltamograma pratila se oksidacija i redukcija dviju amino skupina navedene Schiffove baze. Dobiveni rezultati cikličkih voltamograma snimljenih na elektrodi od staklastog ugljika pokazali su da se Schiffova baza S36 ireverzibilno oksidira. Također se pratio utjecaj promjene koncentracije Schiffove baze S36 pri brzini promjene potencijala od 100 mV/s, te utjecaj brzine promjene potencijala u rasponu od 25 mV/s do 300 mV/s. Pri ovakvim uvjetima visina oksidacijskog strujnog vrha povećavala se s povećanjem koncentracije ispitivane Schiffove baze kao i s brzinom promjene potencijala.In this work, a usage of cyclic voltammetry for the purpose of testing oxido-reduction properties of a newly synthesized Schiff base (1E)-1-N-{[4-(4-{[(E)-N-(2-aminophenyl) carboxyimidoyl] phenoxy} butoxy) phenyl] methilidene} benzene -1,2-diamine, S36 is described. By recording cyclic voltammograms, oxidation and reduction of two amino groups of the mentioned Schiff base were followed. Gained results of the cyclic voltammograms, recordered on glassy carbon electrode, showed that the Schiff base S36 oxidated irreversibly. Also, an influence of concentration change of the Schiff base S36 at scan rate 100 mV/s and influence of scan rate in range between 25 mV/s and 300 mV/s were followed. At these conditions, oxidation peak current was increasing with an increase of a concentration of the tested Schiff base, and scan rate