Non-structural subtype entailment in automata theory

Decidability of non-structural subtype entailment is a long standing open problem in programming language theory. In this paper, we apply automata theoretic methods to characterize the problem equivalently by using regular expressions and word equations. This characterization induces new results on non-structural subtype entailment, constitutes a promising starting point for further investigations on decidability, and explains for the first time why the problem is so difficult. The difficulty is caused by implicit word equations that we make explicit

PMEM of carabid beetles in the agro-ecosystem: Prospects and problems

The comparison of carabid communities sampled at three different field sites during 5 years of ecological biosafety research provides useful information for the design of a post market environmental monitoring of this arthropod family. Each evaluated field site demonstrated a unique composition of carabid species. A baseline for the carabid beetle communities would therefore be necessary for each field site to detect any changes in its composition over time. Aside from the influence of the location, the impacts of weather, the date of sampling and of course the chosen sampling method have to be considered. A standardized method is a basic requirement for a replicable assessment. The number of traps per square meter, and the size and the design of the traps have to be determined a priori. The influence of the weather has to be taken into account and only a monitoring over a longer time period may yield reliable data. Multiple samples taken subsequently during the growing season would minimize potential mistakes in the interpretation of data. However, the main problem implementing a PMEM with carabids considering the mentioned obstacles will be the long-term financing of such a project

Information Security in Small Business

Cílem této diplomové práce je popis zavedení systému bezpečnosti informací do specifického malého podniku. Teoretická část práce shrnuje poznatky a informace o normách a metodikách, vztahujících se k tématu. Analytická část popisuje prostředí konkrétní organizace z pohledu procesního, informačního a ICT. V praktické části je provedena analýza rizik na základě které jsou vybrána vhodná opatření. Závěr praktické části se věnuje doporučením pro nasazení vybraných opatření v podniku a nasazení implementaci ISMS.The aim of this master‘s thesis is the description of the information security implementation into a specific small business. The theoretical part of the paper summarizes the information of related standards and methods. The analytical part describes the process, information and ICT enviroment of a particular organization. The third part of this thesis focuses on a risk analysis and choosing and deployment the relevant controls and their objectives for ISMS implementation.

Subtype satisfiability and entailment

Subtype constraints were introduced in advanced programming language research for designing subtype systems and program analysis algorithms. Two logical problems arise in this context: subtype satisfiability and subtype entailment. Subtype satisfiability underlies subtype inference; subtype entailment is for simplifying subtyping constraints in the same application. In this thesis, we investigate both problems systematically for a number of dialects of subtyping constraint languages that may vary in the following dimensions: types may be simple (finite) or recursive (infinite), type constants may be ordered in lattices or in general partially ordered sets, subtyping can be structural or non-structural, depending on whether least and greatest types are permitted. We use and develop new formal reasoning techniques based on automata, unification, and modal logic. Subtype satisfiability is well understood for all dialects with constants ordered in a lattice. Although cubic time algorithms are given by Palsberg and O\u27Keefe (1995), Pottier (1996), and Palsberg, Wand, and O\u27Keefe (1997), little is known about dialects where constants belong to arbitrary partially ordered sets. We present a uniform treatment to determine the complexities of all these classes. As a consequence, we settle a problem left open by Tiuryn and Wand in 1993 and also subsume complexity bounds given by Wand and Tiuryn (1993), Tiuryn (1992), and Frey (2002). Our results are based on a new connection between modal logic and subtype constraints that we present. Subtype entailment is known to be hard even for simple subtype constraint languages. Rehof and Henglein determined the complexity of structural subtype entailment with type constants ordered in a lattice. They proved coNP-completeness for simple types (1997) and PSPACE-completeness for recursive types (1998). Furthermore, they showed that non-structural subtype entailment is PSPACE-hard and is conjectured PSPACE-complete for the case with only two type constants for the least and greatest types respectively (1998). Yet the problem still remains open today. We argue that the difficulty occurs due to e ects linked to non-regular word languages. In order to do so, we precisely characterize subtype entailment by finite word automata with word equations. This characterization induces new results on non-structural subtype entailment, constituting a promising starting point for future investigation on decidability.Diese Arbeit untersucht zwei logische Probleme der programmiersprachlichen Typinferenz: Erfüllbarkeit und Subsumption von Teiltyp-Constraints. Wir untersuchen diese Probleme systematisch für eine Reihe von Constraintsprachen. Dabei greifen wir auf Methoden der computationalen Logik, Unifikations- und Automatentheorie zurück. Teiltyp-Erfüllbarkeit ist für den Fall wohl verstanden, dass die Typkonstanten in einem Verband angeordnet sind (Palsberg und O\u27Keefe (1995), Pottier (1996), Palsberg, Wand und O\u27Keefe (1997)). Der allgemeinere Fall mit beliebig angeordneten Konstanten wurde bislang weniger untersucht. Wir stellen einen ersten universellen Ansatz vor, indem wir erstmals einen Zusammenhang zwischen Teiltyp-Constraints und Modallogik aufzeigen. Dadurch lösen wir unter Anderem ein seit 1993 offenes Komplexitätsproblem von Wand und Tiuryn. Teiltyp-Subsumption ist selbst für einfachste Constraintsprachen von hoher Komplexität. Rehof und Henglein zeigten dies für den strukturellen Verbandsfall (mit zwei Typkonstanten 1997, 1998), ließen jedoch den nicht-strukturellen Fall offen. In dieser Arbeit betrachten wir den einfachsten nicht-strukturellen Fall. Hier zeigen wir, dass versteckte Wortgleichungen neue Schwierigkeiten verursachen. Hierzu charakterisieren wir Teiltyp-Subsumption durch spezielle endliche Automaten mit Wortgleichungen. Unsere Charakterisierung liefert partielle Entscheidbarkeitsresulte zur nichtstrukturellen Teiltyp-Subsumption und kann als Grundlage für künftige Untersuchungen dienen

Implementation of IPv6 Protocol in Corporate Network

Bakalářská práce se zaměřuje na implementaci protokolu IPv6 v prostředí firemní sítě podniku Teplárny Brno, a.s. V první části obsahuje stručnou definici protokolu, rozdíly oproti IPv4 a teoretický popis fungování. Praktická část se zaměřuje na analýzu současného stavu síťové infrastruktury v reálném prostředí a nabízí možné řešení implementace včetně doporučených zařízení.The bachelor’s thesis focuses on the IPv6 internet protocol implementation in Teplárny Brno, a.s. network. At the first part it contains a brief definition of the protocol, differences between IPv6 and IPv4 and the teoretical description. Practical part is focused on the analysis of the network infrastructure present state in the real enviroment and offers some possible solution to implementation including recommended devices.

Relationship Between People Management Practices and Disruptive Innovation and Organizational Modernity

This study aims to evaluate the relationship between people management practices and disruptive innovation and organizational modernity. The methodological path followed is characterized by a quantitative approach, using the survey procedure for data collection and treatment by means of Structural Equation Modeling Through the structural equation modeling, one can buy that the people management practices have a positive relationship with the organizational modernity; and the organizational modernity has a positive influence on the Disruptive Innovation. It was observed People Management Practices explain 82% Organizational Modernity and People Management and Organizational Modernity explain 78% of Disruptive Innovation. It can be stated that for the sample analyzed Organizational Modernity was confirmed a mediating variabl

First-order theory of subtyping constraints

We investigate the first-order theory of subtyping constraints. We show that the first-order theory of non-structural subtyping is undecidable, and we show that in the case where all constructors are either unary or nullary, the first-order theory is decidable for both structural and non-structural subtyping. The decidability results are shown by reduction to a decision problem on tree automata. This work is a step towards resolving long-standing open problems of the decidability of entailment for non-structural subtyping

Uma ferramenta para auxiliar o desenvolvimento de modelos de carga de servidores web

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Ciência da Computação

An overview of touchless 2D fingerprint recognition

Touchless fingerprint recognition represents a rapidly growing field of research which has been studied for more than a decade. Through a touchless acquisition process, many issues of touch-based systems are circumvented, e.g., the presence of latent fingerprints or distortions caused by pressing fingers on a sensor surface. However, touchless fingerprint recognition systems reveal new challenges. In particular, a reliable detection and focusing of a presented finger as well as an appropriate preprocessing of the acquired finger image represent the most crucial tasks. Also, further issues, e.g., interoperability between touchless and touch-based fingerprints or presentation attack detection, are currently investigated by different research groups. Many works have been proposed so far to put touchless fingerprint recognition into practice. Published approaches range from self identification scenarios with commodity devices, e.g., smartphones, to high performance on-the-move deployments paving the way for new fingerprint recognition application scenarios.This work summarizes the state-of-the-art in the field of touchless 2D fingerprint recognition at each stage of the recognition process. Additionally, technical considerations and trade-offs of the presented methods are discussed along with open issues and challenges. An overview of available research resources completes the work