[pt] Códigos turbo são uma técnica de correção de erro eficiente que vem sendo proposta em diversos padrões de comunicações atuais. Esta técnica apresenta um desempenho que se aproxima dos limites teóricos estabelecidos na Teoria de Codificação. A razão para o excelente desempenho deste tipo de código baseia-se em dois fatores: uma estrutura de codificação composta por codificadores concatenados e uma estrutura de decodificação iterativa. Neste trabalho é realizada uma revisão da literatura onde a decodificação turbo é discutida segundo duas abordagens: uma que baseia-se na estrutura dos codificadores empregados e outra baseada na moderna teoria de grafos- fatores. O desempenho destes códigos é avaliado através de simulações. São considerados fatores como a estrutura dos codificadores, o tipo de modulação empregada, o algoritmo de decodificação utilizado, entre outros. / [en] Turbo codes are an efficient error correcting technique that has been proposed for many communications standards. This technique achieves a performance that is near the theoretical limits established by Information Theory. The reason for this excellent performance of turbo codes relies on two aspects: a coding structure that is composed by concatenated encoders and an iterative decoding procedure. In the literature, two approaches for turbo decoding are presented: one that is based on the encoder structure and another that is built around the factor graphs theory. Both approaches are discussed in this work. Performance evaluation for these codes are obtained through simulations. Some aspects such as encoder structure, modulation scheme and decoding algorithm are considered and evaluated. Also codes derived from turbo codes by puncturing and shortening have been studied in this work.

This thesis examines the various types of transmissions which allow to seamlessly change gears without interrupting the transfer of a motor's power output. In particular, it elaborates on the advantages and disadvantages each design presents for a FormulaStudent/SAE vehicle. Furthermore, the thesis explores the selection of gear ratios and simulates acceleration parameters in order to achieve the best possible dynamic behavior. What is more, the thesis presents a concrete implementation of a transmission for the Husqvarna FE 501 motorcycle redesigned with the Zeroshift mechanism. It includes a fundamental change in the operation of the clutch as well as a gear stress analysis. Last but not least, the TU Brno Racing team incorporated the main conclusions of the thesis into the team's vehicle in order to improve the team's standings in international races.

Summary in Tsonga and English / Ndzavisiso lowu wu xopela xiyimo xa mavumbelo, matsalelo, mahikahatelo na mathyelo ya swikomiso na mavulwankatso eka Xitsonga hi xikongomelo xo bumabumela maringaneriselo ya swona. Switiviwa swi huma eka switshuriwa swo hambanahambana swa nomu na swo tsariwa ku katsa na swa dyondzo (swa vuvulavuri, swihlayahlaya na swihlamuselamarito) swihangalasamahungunyingi na swinavetiso etilayiburari, eswikolweni, emagondzweni, eka tibilibodo na le makhumbini ya miako.Tinxaka ta mikomiso ti kumeka eka swa vanhu (mavito, swiyimo, vuxaka), matiko, tin’hweti, masiku ya vhiki, mavito ya tiholideyi, ya tihuvo, ya mihlangano, ya tiyunivhesiti, nasw. Ku na nkomisokulu (wa switshuriwa swo leha swa ndzungulo na swa nkalandzungulo, xikombiso: xihungwana, vumbiwa) na nkomisotsongo (wa switshuriwa swo koma: xivulwa, xivulwahava, rito, xiaki, peletwana). Lowu ndzavisiso wu pakanise nkomisotsongo. Nkomisotsongo wu paluxa mikhetekanyokulu ya mune ya ‘rikhwanyano’, ‘rivulwankatso’, ‘xikomiso’ na ‘rivulwampfilungano’. Swikombiso hi nandzelelano i: ‘za’ < zela); Huriri/(HRR) < ‘Huvo ya Rixaka ya Ririmi’, na (NSFAS > En-es-FAS). Xikomiso xi tihlawulekisa hi ku peleta kumbe ku komisa hi ku tsala ntsena, rito ra kona ri vuriwa hi ku hetiseka. Rikhwanyano na rivulwankatso swona swi tihlawulekisa hi ku vuleka tanihi rito rohelela. Rivulwampfilungano ri hlanganisa rivulwankatso na xikomiso. Rixaka rin’wana na rin’wana ri tlhela ri va na swivumbeko na mahikahatelo yo hambana. Matirhiselo ya swihikahato ya ya hi milawu ya ririmi ro karhi, xikombiso: nkomiso wa rivitavito wu fanele ku sungula hi letere lerikulu. Ndzavisiso wu paluxa leswaku ku tirhisiwa ka hiko (.) swi fanele ku papalatiwa eka nkomiso hikuva hiko yi teka ndhawu leyi nkomiso wu lwelaka ku hunguta yona hileswi hiko na vangwa swi hlayiwaka tanihi xitekandhawu loko ku hlayeriwa maletere. Ndzavisiso lowu wu basisile matheme lama thyiweke mikomiso eka Xitsonga, ku engetela nhlayo ya mikomiso na ku susumeta misinya yo yi ringanerisa. Ndzi bumabumerile swilaveko na swiyila ku pfuneta vahundzuluxeri na ku va seketela hi ku famba ndzi nyika maritondzingano ya Xinghezi laha swi kotekaka. Switandzhaku swi nyika vumbhoni bya leswaku nhluvuko wa mikomiso eka Xitsonga wa tshikeleriwa hi van’wana va lava nyikiweke matimba yo kondletela ntirho wa vuhundzuluxeri, leswi koxaka ku cinca ka maehleketelo. / This study analyses the state of shortenings (abbreviations and acronyms) in Xitsonga in order to determine their formation, structure, punctuation and naming patterns with the aim of recommending standardisation strategies. The data was collected from various oral and written sources. Various types of shortenings manifest in human phenomena (names, social positions and relations), names of countries, months, weekdays, holidays, boards, organisations, universities, etcetera. There are long shortened texts (e.g. abstracts, summaries) and short texts (sentence, phrase, word, morpheme, syllable). This study focusses on the short texts. Short texts fall into four major categories: ‘compression’, ‘acronym’, ‘abbreviation’ and ‘acreviation’ (combination of acronym and abbreviation). Examples of these forms are respectively ‘za’ < ‘zela’; ‘Huriri’/HRR < ‘Huvo ya Rixaka ya Ririmi’; and NSFAS > En-es- FAS. An ‘Abbreviation’ is characterised by spelling the word letter-by-letter or using it only in writing but uttering its full form when reading, while compression and acronym are characterised by the word’s ‘pronounceability’ in normal syllables. ‘Acreviation’ describes a combination of ‘acronym’ and ‘abbreviation’. Each of these forms further reveals different structural and punctuation patterns. The use of punctuation marks depends on the rules of a specific language, for example, the shortening of a proper name has to begin with a capital letter. The study also reveals that as much as possible, the use of a period should be avoided in the abbreviation as it occupies the space which the abbreviation intends to save because a full stop and space are counted as a character when a word count is done. This study has successfully clarifies the terminology used in the naming of shortenings in Xitsonga, increases the number of shortenings and proposes standardisation guidelines. The researcher recommends do’s and don’t’s for translators and provides English equivalents where applicable. The addenda provide evidence in support of the fact that the development of abbreviations and acronyms in Xitsonga is still thwarted by some individuals who are given coordination roles in translation projects and that a change of mindset is necessary. / African Languages / D. Litt. et Phil. (African Languages)