Switches for FTTx - deployment in networks with IPTV

Cílem této práce bylo seznámit se s přepínači, které mohou být nasazeny v sítích založených na FTTx. První kapitola se zabývá službou IPTV, jejími výhodami, nevýhodami a poskytovanými službami. V následující kapitole jsou rozebírána optická vlákna a možnosti jejich zakončení – FTTH, FTTC, FTTB, FTTO, FTTP a FTTN. Další část zahrnuje metody vysílání a detailnější rozbor multicastových adres včetně definovaných rozsahů a multicastové distribuční stromy. Závěr teoretického rozboru k práci tvoří vysvětlení všech 3 verzí IGMP protokolu a rozdělení přepínačů pomocí přenášených signálů. V praktické části je proveden návrh testování těchto přepínačů. První metoda představuje testování pomocí jednoho video souboru v různém rozlišení. Další možnost testování je založena na první metodě, avšak s tím rozdílem, že testování probíhá se dvěma streamy, z nichž každý má rozdílný datový tok. Poslední testování slouží k dokázání faktu, že se video tok přenáší pomocí multicastu, nikoli každý tok ze serveru ke klientovi zvlášť. Spojení mezi přepínači bylo omezeno na 10 Mb/s a zvolený video soubor dosahuje právě těchto průměrných přenosových hodnot.The aim of this paper was to acknowledge ourselves with the switches which can be used in the networks based on FTTx. The first chapter deals with the IPTV service, its advantages, disadvantages and provided services. In the following chapter, optical fibres and the possibilities of their termination are discussed - FTTH, FTTC, FTTB, FTTO, FTTP and FTTN. The next part involves the methods of broadcasting and more detailed analysis of multicast addresses including defined range and multicast distributional trees. The conclusion of the theoretical analysis of this paper is formed by the explanation of all 3 versions of the IGMP record and the division of switchers through the signals transmitted. In the practical part, the suggestion of testing these switchers is carried out. The first method represents testing through one video file in various resolutions. Another possibility of testing is based on the first method, nevertheless, with the difference that the testing is done in two streams and each one of them has a different data flow. The purpose of the last testing is to demonstrate the fact that the video flow is transmitted through multicast, not every single flow from a server to a client separately. The connection between switchers was reduced to 10 Mb/s and the chosen video file runs at these average transmission data.

A Model of User Preference Learning for Content-Based Recommender Systems

This paper focuses to a formal model of user preference learning for content-based recommender systems. First, some fundamental and special requirements to user preference learning are identified and proposed. Three learning tasks are introduced as the exact, the order preserving and the iterative user preference learning tasks. The first two tasks concern the situation where we have the user's rating available for a large part of objects. The third task does not require any prior knowledge about the user's ratings (i.e. the user's rating history). Local and global preferences are distinguished in the presented model. Methods for learning these preferences are discussed. Finally, experiments and future work will be described

How to Solve the Price Puzzle? A Meta-Analysis

The short-run increase in prices following an unexpected tightening of monetary policy represents a frequently reported puzzle. Yet the puzzle is easy to explain away when all published models are quantitatively reviewed. We collect and examine about 1,000 point estimates of impulse responses from 70 articles using vector autoregressive models to study monetary transmission in various countries. We find some evidence of publication selection against the price puzzle in the literature, but our results also suggest that the reported puzzle is mostly caused by model misspecifications. Finally, the long-run response of prices to monetary policy shocks depends on the characteristics of the economy.Monetary policy transmission; Price puzzle; Meta-analysis; Publication selection bias

Services Optimization in FTTx Optical Access Networks

Tato práce se zabývá optimalizací služeb Triple Play a bezpečností v optických přístupových sítích. První kapitola poskytuje teoretický základ pro vyhodnocení výsledků práce. Druhá kapitola popisuje optické přístupové sítě definované podle ITU. Popsány jsou parametry optických sítí: přenosové rychlosti, dělicí poměr, linkový kód, limitní bitovou chybovost aj. Třetí kapitola vysvětluje současný stav v oblasti budování optických sítí v souladu s plánem rozvoje podle Evropské unie. Praktická část práce je rozdělena do několika podkapitol. Významná část výsledků se věnuje zabezpečení pasivních optických sítí a navržením vhodného zabezpečení pro stávající sítě. K tomuto účelu slouží mimo jiné unikátní parametr doba šíření ve spojení s přepracovaným zabezpečovacím mechanismem. Další podkapitoly se věnují analýze řídicího a datového provozu v gigabitových optických sítích. Výsledky měření byly použitý pro návrh nového algoritmu připojování koncových jednotek, který zkrátí tuto dobu a dále pro návrh algoritmu pro detekci modifikované koncové jednotky. Předposlední kapitola se zabývá vytvořením ILP modelu pro přenos Triple Play služeb. Poslední kapitola sestává ze simulací vlastní implementace přenosové vrstvy v simulačním nástroji VPIphotonics.This thesis deals with an optimization of Triple play services and security in optical access networks. The first chapter provides theory basics which are necessary for results evaluation. The second chapter describes optical access networks with their parameters such as transmission speed, split ratio, line code, bit error rate etc. defined by ITU. Next chapter summaries the current state in optical networks construction field according to the European Union developing plan. The practical part of this thesis is divided into several subchapters. The significant part of the thesis is dedicated to the security of passive optical networks and design of proper security model for current networks. For this purpose, the unique parameter time propagation Tprop, with the novel security model was developed. Next part of the thesis provides an analysis of control traffic and data traffic in the gigabit passive optical networks. For a novel algorithm in activation process in gigabit passive optical networks the measurement results were used. The novel algorithm decreases the total time needed for this process. The last but one subchapter deals with an ILP model for Triple Play services. The last subchapter contains the own implementation of the transmission converge layer in VPIphotonics simulation tool.

(The Narrative Structures in the Wild West Stories. The Oil Prince Case

The article is based on the analysis by John G. Cawelti saying that the western formula cannot be attached to a single plot pattern but rather to a symbolic chronotope and its influence on the type of a hero who operates within the chronotope. I use examples of some writings (M. Bird, F. Parkman, O. Wister, J. Altsheller, M. Brand, E. Haycox, Z. Grey and others) to demonstrate several narrative structures used in westerns: the schemes of chasing, revenge, an armed conflict between groups of characters (or a duel), the scheme of hunting for a treasure, the travel scheme as well as the scheme of a detective novel, which may be incorporated into the western. I include a detailed analysis of Karl May´s novel The Oil Prince (Der Ölprinz, 1893). I reveal the principles of the Mayesque serial fictitious universe (the principle of a returning character and hierarchical ranks of characters) as well as the literary-historical genesis of the Winnetou saga in the published short stories. Two types of stories can be identified within May´s text corpus: the ones having the paratactic narrative structure (inherited from the picaresque novel) and those having a central plot, which also include the Oil Prince. Its narrative structure is organized by the central motif of a fake oil lake trap (what the lake actually hides is the fact it does not hide anything: as there is no oil well, in fact). The narrative line of the bad guys is opposed by the narrative line of the positive characters, who want to save a banker´s life. Both narrative lines are interrelated by means of the manifold chasing/tracking narrative structure (several groups of characters chase each other) depicted by the alternate storyline composition switching between that of the good backwoodsmen and that of the bad guys. On the level of narrative point of view the alternate storyline composition is reflected in alternate focalization, which makes the model readers identify themselves alternately with either the good or the bad characters. Even jeopardizing the negative characters narrative line makes readers feel suspence and frustration. Both of the narrative lines are – on the microlevel – constructed as the solutions of the narrative problems (e.g being captured – being freed, a tough situation – trick and so on): the positive characters deal with ad hoc tasks, problems, which they are faced with, using their common sense (phronesis) so as to assess and solve a particular situation, and their skills and physical condition. I include a detailed analysis of the trick pattern in the case of the Old Shatterhand character. On the other hand, the negative characters deal with being in danger by telling lies or killing. In conlusion, I bring intertextual examples of the Mayesque fictitious world in the proses by J. F. Cooper, F. Gerstäcker, G. Ferry, T. M. Reid, Ch. Sealsfield on the level of motifs, on the level of the hero construction as well as on the level of the narrative structure (the composition of alternate story lines of the positive and negative characters in F. Gerstäcker´s work)

Subject and Madness. Peter Kompiš´s Novel Wanderings of a Great Wizard

The study interprets the novel by Peter Kompiš Bludná púť velikého čarodeja (Wanderings of a Great Wizard, 1929) in terms of the way the literary subject in constituted in the text and in respect of the literary representation of madness. Within the context of Slovak inter-war prose I classify the novel as the theme invariant of a character breaking out of the social relationships and the inter-subjective world. I raise the question what concept of subject is assumed in the type of madness which is represented in the text. On the topological text level, the motif of madness causes the discontinuity of chronotopes, on the motif level, flying motifs (supposedly „astral travels“ of a soul set free of the body). The semantic curve of the subject transformation in the text leads from the absolute „divine“ subjet, voluntarily ruling the reality (when the character´s madness bridges the gap between self and not-self) to a subordinate, dependant subject (the character eventually becomes a slave to a mad „theatrical“ performance). This subject transformation in the text is considered to be a modernist (Modern-dependant) subject and is also found in the writings by the modernist Ján Hrušovský. The supposedly original philosophy of the literary character Rojko (Dreamer) is an inter-textual patchwork of the motifs present in the contemporary philosophies (e.g. the „super-human“ concept) as well as gnosticism and is generated, like the motifs of hallucination, by the character´s magalomaniac figment of immagination. The representation of madness in the text is enabled by Modern-Age subject constitution, which is opposed to the world and is presented as the basis and the source of the reality representation: thus the gap between self and not-self is bridged even further

Švantner, horror, fantasy: genre parameters

The analysis of the texts in the study seeks to prove the hypothesis that most of František Švantner´s short stories from the collection Malka (1942) belong to the genre of fantasy as it is defined by Tzvetan Todorov: the endings of most stories leave the reader oscillating between the natural and supernatural interpretations of the plot. The epistemological status of numerous events in the story is ambivalent. Švantner´s texts generate the fantasy effect by means of motif focalisation: each hypothetically supernatural motíf is focalised through a literary character´s perspective. The suyzhet must be reconstructed by a model reader in the text – this suyzhet is set in the crossing point of different characters´ (contradictory) dialogue perspectives. Another method of generating the fantasy effect is a blank space in the text, a missing story syntagm (a data concealing approach) and the inversion of time coordinates, when e.g. the emergence of a character who was already dead at that time (which the reader does not learn until the end) allows the „psychic“ interpretation, too. Emphasising the genre dimensions of Švantner´s texts may also fulfil an important role in the literary life when translating these texts into a foreign literature: hypothetically, they could be introduced into a new literary context as a sample of a particular genre rather than as a sample of Slovak literature

A Literary Work as an Event and Idiolect

The study deals with situating a literary work between general properties (laws) of literary discourse and singularity, between institution and idiom. According to Derrida, singularity cannot be achieved without participation in generality. A literary work as a singularity is not isolated – in order to be read as a singularity, it must be juxtaposed with other works, which it differs radically from. G. Deleuze paraphrases Proust saying that a writer invents a new language within a language. This other language within the previous natural and literary language, however, does not only have to function on the linguistic (stylistic) level, but also on the level of the „secondary language “, the system of literary codes and conventions. It may transcribe and transform not only the level of language in the common sense (deviated syntax) but also genre conventions (e.g. deviated crime story), literary etiquette. This language is not torn off the „old language “ (primary system), but it is created as its redesign. From the viewpoint of the „middle“ perspective of an individual literary work, the work (event) can thus become – for instance – a radical transformation of a particular genre structure. The genre norm, which is overcome by the given work, becomes a system of conventions, with regards to which this work is comprehensible: a genre is a condition of possibility of partial comprehensibility of an innovative work. Such a work is a sort of message partly encoded in a familiar language which flows into an unexpected, unknown language. A work – singularity, an event establishes a new code – idiolect. The work – event (an event as something that is unrepeatable by definition) is thus – according to Derrida – always pre-infected with a repetition structure so that it could be read at all

Self propelling articulated boom

Tato bakalářská práce obsahuje rozdělení pracovních plošin, rozbor konstrukčních prvků kloubových pracovních plošin, kritickou rešerši současných konstrukčních řešení těchto plošin, konstrukční návrh pracovního koše s nosností 350 kg, funkční a pevnostní výpočty nosné konstrukce, návrh přímočarého hydromotoru a výkresovou dokumentaci.This bachelor thesis contains the division of working platforms, analysis of structural elements of articulated work platforms, critical research of current design solutions of these platforms, design of a working basket with a load capacity of 350 kg, functional and strength calculations of load bearing structure, design of a linear hydraulic motor and drawing documentation.