Complexity of testing morphic primitivity

We analyze the algorithm in [Holub, 2009], which decides whether a given word is a fixed point of a nontrivial morphism. We show that it can be implemented to have complexity in O(mn), where n is the length of the word and m the size of the alphabet

Establishment of the Linux internet gateway using advanced filtering

Práce Realizace internetové brány na Linuxu s pokročilým filtrováním se soustřeďuje na~instalaci operačního systému Linux na~starší počítače, který plní funkci jako brána pro připojení klientů ve~vnitřní síti do internetu. V práci je uveden popis vytvoření pokročilého filtrování s~pomocí iptables. Ukazuje některé typy bezpečnosti proti útokům z Internetu. V~dalších kapitolách jsou probrány pokročilé mechanismy řízení provozu (jako tc a qdisc). Tento systém front se ukazuje jako velice přínosný všude tam, kde je potřeba hierarchicky dělit provoz mezi uživatele. Jsou popsány typy front a~sestavena konfigurace pro klienty ve vnitřní síti. Dále je uvedeno použití dns serveru typu caching-only a také aplikace denyhosts, která zvyšuje celkovou bezpecnost systému. Mít vlastní DNS server se osvědčuje, zejména pokud chceme snížit datový provoz. Poslední kapitola se zabývá radius serverem a jeho implementací s použitím apache a databáze mysql. Popsány jsou možnosti některých konfiguračních voleb jednotlivých služeb a také uvedeny příklady konfigurací. Nakonec je předveden systém pro autentizaci uživatelů skrze RADIUS server. Celá práce se snaží poskytnout komplexní pohled na problematiku bezpečnosti a~filtrování.The thesis Establishment of the Linux internet gateway using advanced filtering focuses on~the installation of~the Linux operating system on~the older computers, that functions as a gateway to connect clients in the internal network to the Internet. The thesis describes creation an advanced filter with using iptables. Shows some types of security against attacks from the Internet. The other chapters are discussed, advanced traffic control mechanism (such as a TC and a qdisc). The system queue, it is highly beneficial where it is necessary to hierarchically divide traffic between users. It describes types of queue and assembled configurations for clients in the internal network. Next chapter describes the DNS server caching-only type and application denyhosts, which increases the overall security system. Have your own DNS server is certified, especially if we want to reduce the data traffic. Last chapter describes the RADIUS server and its implementation using Apache and MySQL database. Furthermore, the configuration options are described and the examples of the particular configurations are provided. Finally, it presented a system for authentication through the RADIUS server. The thesis seeks to provide a~complex view of security and filtering.

The present SP tests for determining the transition temperature TSP on "U" notch disc specimens

The principal difference between the small punch (SP) testing technique and standardized impact testing lies in the fact that the SP tests carried out in accordance with CWA 15627 Small Punch Test Method for Metallic Materials use disc-shaped test specimens without a notch. Especially in tough materials, the temperature dependence of SP fracture energy ESP in the transition area is very steep and lies close to the temperature of liquid nitrogen. In this case, the determination of SP transition temperature TSP can lead to significant errors in its determination. Efforts to move the transition area of penetration testing closer to the transition area of standardized impact tests led to the proposal of the notched disc specimen 8 mm in diameter and 0.5 mm in thickness with a "U" shaped notch 0.2 mm deep in the axis plane of the disc. The paper summarizes the results obtained to date when determining the transition temperature of SP tests TSP, determined according to CWA 15627 for material of pipes made of P92, P22, and a heat treated 14MoV6-3 steel in the as delivered state. Although the results obtained confirmed the results of other works in that the presence of a notch in a SP disc is insufficient to increase the transition temperature significantly and certainly not to the values obtained by Charpy testing, comparison of the different behaviors of the alloys tested reveals some evidence that the notch reduces the energy for initiation. This implies that the test on a notched disc is more a test of crack growth and would be a useful instrument if included in the forthcoming EU standard for SP testing.Web of Science105art. no. 49

Study on temper embrittlement and hydrogen embrittlement of a hydrogenation reactor by small punch test

The study on temper embrittlement and hydrogen embrittlement of a test block from a 3Cr1Mo1/4V hydrogenation reactor after ten years of service was carried out by small punch test (SPT) at different temperatures. The SPT fracture energy E-sp (derived from integrating the load-displacement curve) divided by the maximum load (F-m) of SPT was used to fit the E-sp/F-m versus-temperature curve to determine the energy transition temperature (T-sp) which corresponded to the ductile-brittle transition temperature of the Charpy impact test. The results indicated that the ratio of E-sp/F-m could better represent the energy of transition in SPT compared with E-sp. The ductile-to-brittle transition temperature of the four different types of materials was measured using the hydrogen charging test by SPT. These four types of materials included the base metal and the weld metal in the as-received state, and the base metal and the weld metal in the de-embrittled state. The results showed that there was a degree of temper embrittlement in the base metal and the weld metal after ten years of service at 390 degrees C. The specimens became slightly more brittle but this was not obvious after hydrogen charging. Because the toughness of the material of the hydrogenation reactor was very good, the flat samples of SPT could not characterize the energy transition temperature within the liquid nitrogen temperature. Additionally, there was no synergetic effect of temper embrittlement and hydrogen embrittlement found in 3Cr1Mo1/4V steel.Web of Science106art. no. 67

Crop Fertilization on East Texas Soils.

4 p

Planning routes for recreational cycling

Rekreační jízda na kole se v poslední době stává čím dál více rozšířenou kratochvílí. Většina cykloaplikací nabízí plánování, které funguje skvěle pro nejkratší cestu z bodu do bodu, ale pro plánování rekreačních tras se moc nehodí. Proto jsem se rozhodl vytvořit řešení, které by tyto trasy nabízelo. Udělal jsem důkladný průzkum prací s podobnou tématikou. A poté jsem z nich jednu, která se zabývá plánováním okružních výletů, vybral, abych ji implementoval a modifikoval pro svůj problém. Musel jsem kvůli tomu tento problém formálně definovat. Poté jsem popsal komponenty potřebné k jeho řešení, jako je příjemnost a kulatost těchto tras. Dále jsem rozebral samotné řešení, které se inspirovalo zmíněnou prací a rozšířil ho kromě okruhů i na rekreační trasy z bodu do bodu. Později jsem identifikoval jeho slabiny a vytvořil upravenou verzi řešení, kde se na ně zaměřuji. Navíc jsem implementoval obě řešení v Javě a vytvořil nad nimi webovou službu, společně s klientem, který může jejich možnosti demonstrovat uživateli. Poslední část je věnovaná experimentům, které mají za úkol porovnat obě řešení a pojmenovat jejich rozdíly. Tyto experimenty ukázaly, že výsledky modifikovaného algoritmu nejsou výrazně odlišné od původní verze. Nicméně, algoritmus zaznamenal výrazné zlepšení v oblasti časové náročnosti.Using bicycle rides as a leisure activity is very widespread these days. Most of the cycling-focused applications offer planning methods that are great to use when traveling from place to place but are not useful when planning routes suitable for recreational cycling. That's why I decided to propose and implement a solution that would offer planning of such tours. I did a thorough research of papers with a similar scope. Then I chose one of them, which was focused on planning closed routes, and I implemented and modified it for my problem. To achieve this, I defined the problem of planning recreational tours formally. Then I described components necessary for its solution, for example, tour pleasantness and roundness. Next, I covered the solution itself, drawn from the mentioned paper, but extended to plan point-to-point recreational routes as well as closed ones. I identified weak points of the solution and created a modified version where they were targeted. Moreover, I implemented both solutions in Java and created a web service on top of them. The web service comes together with a client which can demonstrate capabilities of these algorithms to the user. The last section is dedicated to experiments that are comparing the solutions of the original application with the modified one and identifying their differences. These experiments have shown that there is not any significant difference in the quality of results from the modified version of the algorithm. However, there is a significant improvement in the overall running time

Biopolymer composites with plant fibers jute and coconut

57 s. :obr., tab., grafy +CD ROMBakalářská práce se zabývá přípravou a hodnocením fyzikálních, reologických a mechanických vlastností biopolymerních kompozitů s rostlinnými vlákny juty a kokosu v závislosti na jejich hmotnostním obsahu. Pro experimentální měření byly použity biopolymerní matrice polyethylenu (BioPE) a kyseliny polymléčné (PLA)

Integrating climate change mitigation and adaptation in agriculture and forestry: opportunities and trade-offs

This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.International audienceAlthough many activities can jointly contribute to the climate change strategies of adaptation and mitigation, climate policies have generally treated these strategies separately. In recent years, there has been a growing interest shown by practitioners in agriculture, forestry, and landscape management in the links between the two strategies. This review explores the opportunities and trade-offs when managing landscapes for both climate change mitigation and adaptation; different conceptua-lizations of the links between adaptation and mitigation are highlighted. Under a first conceptualization of 'joint outcomes,' several reviewed studies analyze how activities without climatic objectives deliver joint adaptation and mitigation outcomes. In a second conceptualization of 'unintended side effects,' the focus is on how activities aimed at only one climate objective—either adaptation or mitigation—can deliver outcomes for the other objective. A third conceptualization of 'joint objectives' highlights that associating both adaptation and mitigation objectives in a climate-related activity can influence its outcomes because of multiple possible interactions. The review reveals a diversity of reasons for mainstreaming adaptation and mitigation separately or jointly in landscape management. The three broad conceptualizations of the links between adaptation and mitigation suggest different implications for climate policy mainstreaming and integration