The analysis of human communication, in all its forms, increasingly depends on large collections of texts and transcribed recordings. These collections, or corpora, are often richly annotated with structural information. These datasets are extremely large so manual analysis is only successful up to a point. As such, significant effort has recently been invested in automatic techniques for extracting and analyzing these massive data sets. However, further progress on analytical tools is confronted by three major challenges. First, we need the right data model. Second, we need to understand the theoretical foundations of query languages on that data model. Finally, we need to know the expressive requirements for general purpose query language with respect to linguistics. This thesis has addressed all three of these issues. / Specifically, this thesis studies formalisms used by linguists and database theorists to describe tree structured data. Specifically, Propositional dynamic logic and monadic second-order logic. These formalisms have been used to reason about a number of tree querying languages and their applicability to the linguistic tree query problem. We identify a comprehensive set of linguistic tree query requirements and the level of expressiveness needed to implement them. The main result of this study is that the required level of expressiveness of linguistic tree query is that of the first-order predicate calculus over trees. / This formal approach has resulted in a convergence between two seemingly disparate fields of study. Further work in the intersection of linguistics and database theory should also pave the way for theoretically well-founded future work in this area. This, in turn, will lead to better tools for linguistic analysis and data management, and more comprehensive theories of human language.

Zugl.: Lübeck, Univ., Diss., 2008

Konstanz, Univ., Masterarbeit, 2004.

Konstanz, Univ., Master-Arb., 2003.

Essen, University Duisburg-Essen, Informatik und Wirtschaftsinformatik, Diss., 2005--Duisburg.

Duisburg, Essen, Univ. Duisburg-Essen, Informatik und Wirtschaftsinformatik, Diss., 2005

Darbe nagrinėjama plačiausiai praktikoje paplitusiems duomenų šaltiniams – reliacinėms duomenų bazėms ir XML dokumentams – skirtų užklausų kalbų - SQL, XQuery ir XPath - užklausų struktūra ir savybės. Remiantis analizės rezultatais, sudarytas bendrinis užklausų modelis, kurio paskirtis – padėti formuoti vartotojų užklausas nepriklausomai nuo to, kokiomis technologijomis realizuoti duomenų šaltiniai. Sukurto modelio praktinio taikomumo galimybėms pademonstruoti pateikta juo paremta paieškos sistemos kūrimo metodika. / The thesis presents the analysis of SQL, XQuery and XPath query languages that are intended for the most widely used data sources, namely relational databases and XML documents. Based on the results of the analysis, a generic query model has been developed. The model should serve to help compose user queries without the context of a specific data source implementation technology. The applicability of the model in practice is demonstrated by creating methods for search system development, based on this model.

Darbas apie apsisaugojimo metodiką nuo injekcinių atakų naudojant Bekaus ir Nauro formą. Pasirinkta įvesties patikros strategija (blacklist), realizuotas reguliarių išraiškų transformacijos algoritmas. Sukurtas pradinis injekcinių atakų aprašas. Transformuojant aprašo sematiką į reguliarių išraiškų masyvus yra suformuojamos tikrinimo taisyklės. Pagal suformuotas taisyklės yra nustatoma, ar sistemos įvesties parametrai atitinka injekcinių atakų aprašą. Sukurtas saugos sistemos prototipas apsaugai nuo injekcinių atakų. / In this research the injection attack prevention method is introduced. Also the interactive security system prototype to protect against injections attacks is proposed. Security system prototype is using blacklist input validation strategy for checking input parameters. Each list item consists of a single type of injection attack description. Descriptions are written in Backus–Naur form.

Konstanz, Univ., Diplomarbeit, 2008.

Konstanz, Univ., Bachelorarb., 2004.