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Texting has often been treated as verbally minimalist, notionally transactional, and, consequently, expressively impaired due to its text-only (mono-modal) character. Despite this, even with the development of new modes of electronically mediated communication (EMC) which made available a wide range of rich (multi-modal) communicative possibilities, texting has maintained its well-established position. This thesis approaches texting as communicatively rich and explores its expressive possibilities in the context of establishing texters’ deictic centres and representing aspects of physicality. Based on the analysis of nearly two thousand text-messages written by British and Polish native speakers and subsequent semi-formal interviews with the senders, I argue that senders position themselves discursively at one of four locations: their own physical deictic centre, the deictic centre of their communicative partner, a mutually agreed space distinct from either of their deictic centres, or a joint (virtual) communicative location with the recipient. I recognise the existence of social location and negative location, as well as location expressed through actions and motion. Additionally, I establish that physicality and body are represented through a variety of enacted (rather than described) sensory information, including auditory, visual, and kinaesthetic. Through the employment of these discursive tools, which follow certain presentation rules, texters create their alterae personae through which actions are performed in virtual space. I argue that text-messages should not be treated as monomodal, but as characterised by embedded multimodality, a term which I introduce. Methodologically, I draw on interactional sociolinguistics (e.g., Gumperz 1982; Tannen semantics (e.g., Lyons 1977; Talmy 1985; Fauconnier 1985), text-grammar (Nunberg 1990), mediated discourse analysis (e.g., Scollon and Levine 2004), and multimodal discourse analysis (e.g., Norris 2004). This interdisciplinary study advances current knowledge about discursive self-positioning and self-presentation in EMC, and provides insights about texting as a mode of communication that offers wide expressive possibilities despite its physical restrictions. As well as adding to theoretical discussion about motion verbs and performativity, the study contributes to research on deixis, physicality, and place, the expression of which is manifested in text-messages. 1989), performativity and speech act theory (e.g., Austin 1962; Searle 1975, 1979).

<p>Future radars require more flexible and faster radar signal processing chain than commercial radars of today. This means that the demands on the processors in a radar signal system, and the desire to be able to compute larger amount of data in lesser time, is constantly increasing. This thesis focuses on commercial micro-processors of today that can be used for Active Electronically Scanned Array Antenna (AESA) based radar, their physical size, power consumption and performance must to be taken into consideration. The evaluation is based on theoretical comparisons among some of the latest processors provided by PACT, PicoChip, Intrinsity, Clearspeed and IBM. The project also includes a benchmark made on PowerPC G5 from IBM, which shows the calculation time for different Fast Fourier Transforms (FFTs). The benchmark on the PowerPC G5 shows that it is up to 5 times faster than its predecessor PowerPC G4 when it comes to calculate FFTs, but it only consumes twice the power. This is due to the fact that PowerPC G5 has a double word length and almost twice the frequency. Even if this seems as a good result, all the PowerPC´s that are needed to reach the performance for an AESA radar chain would consume too much power. The thesis ends up with a discussion about the traditional architectures and the new multi-core architectures. The future belongs with almost certainty to some kind of multicore processor concept, because of its higher performance per watt. But the traditional single core processor is probably the best choice for more moderate-performance systems of today, if you as developer looking for a traditional way of programing processors.</p>

Future radars require more flexible and faster radar signal processing chain than commercial radars of today. This means that the demands on the processors in a radar signal system, and the desire to be able to compute larger amount of data in lesser time, is constantly increasing. This thesis focuses on commercial micro-processors of today that can be used for Active Electronically Scanned Array Antenna (AESA) based radar, their physical size, power consumption and performance must to be taken into consideration. The evaluation is based on theoretical comparisons among some of the latest processors provided by PACT, PicoChip, Intrinsity, Clearspeed and IBM. The project also includes a benchmark made on PowerPC G5 from IBM, which shows the calculation time for different Fast Fourier Transforms (FFTs). The benchmark on the PowerPC G5 shows that it is up to 5 times faster than its predecessor PowerPC G4 when it comes to calculate FFTs, but it only consumes twice the power. This is due to the fact that PowerPC G5 has a double word length and almost twice the frequency. Even if this seems as a good result, all the PowerPC´s that are needed to reach the performance for an AESA radar chain would consume too much power. The thesis ends up with a discussion about the traditional architectures and the new multi-core architectures. The future belongs with almost certainty to some kind of multicore processor concept, because of its higher performance per watt. But the traditional single core processor is probably the best choice for more moderate-performance systems of today, if you as developer looking for a traditional way of programing processors.

Thesis(M.S.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references (p.47-50).

M.Ing. / This work considers a dual band electronically steerable parasitic array radiator (ESPAR) antenna system. This system is designed with one actively fed radiating element and N-parasitic radiating elements. The radiation pattern can be electronically controlled by means of the loads terminating the parasitic elements. The antenna system is designed as ESPAR to have a minimum number of controlling elements thereby minimising the power consumed. The dual band operation of this antenna is for the frequency bands of the wireless local area network (WLAN), which are 2.412-2.482 GHz for IEEE 802.11b/g (known as the 2.4 GHz band) and 5.15-5.825 GHz for IEEE 802.11a (known as the 5 GHz band). In the upper band, only the 5.8 GHz sub-band was considered. The dual-band capability was targeted by conducting a structural parameter modification on the antenna system. The structural modification involves optimisation of the length of the active element, the length of the parasitic element, the distance of the parasitic element from the active element and most importantly, by application of a loading technique on the elements. The loading was done by using optimisation tools, such as fminsearch, fminbnd and the genetic algorithm. The specific circuit that was used for the loading was a series connection inductors inserted into the antenna’s elements at positions found via a global optimization.. The method used was to first identify the optimal length per specific resonant frequency and consider the optimal length with respect to both resonant frequencies. The second step was to load the three resulting optimised different monopoles, and the loading with results closest to the requirements. The optimum monopole of the three in the second step was then used as the fixed input parameter for the main optimisation of ESPAR antenna. Using a ground plane with a skirt, an acceptable return loss performance has been achieved for the antenna's main building M.J. Bembe ii block, a monopole element, in both frequency bands. The challenge was found in steering of the beam in different directions; it was then concluded that the usage of more elements could provide the necessary freedom for the optimisation process. Six elements were arranged symmetrically close to the active fed element in order to achieve a dual band resonance, with different designs meeting the requirements differently. This is the first report showing an ESPAR antenna optimisation which includes the loading of elements with lengths and distance optimisation.

The boom of the internet economy and the smartphone explosion currently experienced in South Africa is making it increasingly more convenient for South African residents to purchase electronically supplied goods and services from suppliers located all across the globe with the mere click of a button. The increasing number of purchases online is making it almost impossible for the South African Revenue Service to collect the Value-Added Tax on specifically electronically supplied services purchased from foreign suppliers. It is further placing South African suppliers of similar goods and services in a disadvantaged position in respect of pricing when compared to foreign suppliers. In the 2013 budget speech, the Minister of Finance indicated that the Value-Added Tax implications of the supply of digitised products by foreign suppliers are an area of concern. By July 2013 proposals were contained in the Draft Taxation Laws Amendment Bill to address this very problem. The aim of this study is to critically evaluate the proposed methods to collect Value-Added Tax on electronically supplied services, as contained in the Draft Taxation Laws Amendment Bill through a detailed literature review and critical evaluation. The literature review focuses on sections 7(1)(c) and 14 of the Value-Added Tax Act, the sections of the Value-Added Tax Act which currently regulates the collection of Value-Added Tax on electronically supplied services, as well as the methods used in the European Union and New Zealand to collect Value-Added Tax and Goods and Services Tax on electronically supplied services. The critical evaluation of the proposals identifies shortcomings and provides recommendations to overcome the shortcomings to ensure that the proposed changes will address the concerns and align South African legislation with global practices. The study concludes that, although the proposed changes to the method to collect Value-Added Tax on electronically supplied services are a step in the right direction, there is still work to be done by legislators on the details of the proposals to ensure successful implementation in a South African environment. / Dissertation (MCom)--University of Pretoria, 2014. / am2014 / Taxation / unrestricted

Faculty of Engineering and the Built Environment; School of Electrical and Information System; MSC Dissertation / In this paper, the Electronically Steerable Parasitic Array Radiator (ESPAR) antenna, developed by the Advanced Telecommunications Research Institute (ATR) in Japan was analyzed to determine its feasibility as a low cost direction finding (DF) system. Simulations of the antenna were performed in SuperNEC and Matlab was used to determine the direction of arrival (DOA) using the Reactance Domain multiple signal classification (MUSIC) algorithm. Results show the ideal configuration has 6 parasitic elements with a diameter of 0.5 . Up to 5 periodic, uncorrelated signals spread 360° in azimuth and above 45° elevation produce sharp peaks in the MUSIC spectra. Azimuth separations of only 2° at 40 dB are resolvable while signals arriving with 25% full power are still detectable. For the DOA to be resolved the radiation pattern should be asymmetrical and hence the reactance set should have a range of unequal values. Comparative results show that the 6 element ESPAR offers excellent overall performance despite the reduction in cost and is comparable in performance to the 6 element uniform linear array.

Peroxidase de rábano (\"horseradish peroxidase - HRP), atuando como uma oxidase frente a substratos apropriados, catalisa a formação de espécies eletronicamente excitadas triplete. Os produtos obtidos são os esperados da clivagem de um intermediário 1,2-dioxetânico hipotético. Espécies tripletes geradas enzimaticamente são capazes de transferir energia a vários aceptores incluindo macromoléculas tais como: fitocromo, RNA, DNA e proteínas, além de organelas como cloroplastos. Acompanhamos a oxidação aeróbica de aldeídos alifáticos lineares (C2-C6) catalisada pela HRP; esta reação gera o aldeído inferior (Cn-1) no estado excitado triplete e ácido fórmico. Dois aspectos principais são abordados neste trabalho: (i) análise dos resultados em base ao comprimento da cadeia carbônica do substrato (C2 &#8594; C6) e (ii) a procura de emissões sensitizadas em estruturas biológicas (cloroplastos e microsomas). - Oxidação aeróbica dos aldeídos alifáticos lineares C2-C6 catalisada pela HRP. Corantes xantênicos e clorofila a solubilizada em micelas foram utilizados para monitorar estados eletronicamente excitadas geradas pela oxidação aeróbica dos aldeídos alifáticos lineares catalisada pela HRP. Quando eosina é o aceptor fluorescente, máxima emissão ocorre com butanal. Este resultado é discutido em conecçao com o fato de que uma série de efeitos biológicos de ácidos alifáticos lineares são máximos com o ácido butírico. A possível paticipação de estados excitados no processo que desencadeia as atividades biológicas deste ácido é sugerida. - TransferêncIa de energia para cloroplastos. Aldeídos alifáticos lineares (C2-C6) promovem emissão em cloroplastos na região de fluorescência de clorofila. Esta habilidade deve provavelmente constituir um caso de \"luminescência escura\" (\"dark luminescence\") . Se HRP estiver presente o aldeído (Cn) é oxidado ao homólogo inferior (Cn-1) no estado triplete, o qual sensitiza direta e/ou indiretamente a fluorescência de clorofila. Clorofila excitada por este processo é incapaz de reduzir um aceptor de Hill. - Quimioluminescência de microsomas expostos à oxidação aeróbica de aldeídos lineares catalisada pela HRP. Microsomas expostos ao sistema propanal/HRP/O2 desenvolvem luminescência de baixa intensidade. Este processo emissivo é distinto daquele originário durante a peroxidação de lipídeos uma vez que: (i ) a emissão se situa próxima a 560 nm e não na região espectral do vermelho (como esperado para a emissão bimol de oxigênio singlete) e (ii) não há formação de malonaldeído. Acetaldeído triplete parecer ser a espécie responsável pela indução deste processo através da excitação de algum componente microsomal, possivelmente uma flavoproteína. / Horseradish peroxidase (HRP), acting as anoxidase upon appropriate substrates, promotes the formation of electronically excite triplet species. The products obtained are those which would be expected from the cleavage of a hypothetical 1,2 dioxetane intermediate. Enzyme-generated triplet species are able to transfer energy to several acceptors, including macromolecules such as phytochrome, RNA, DNA and proteins, as well as to organeles such as chloroplasts. In the present study, we investigated the HRP-catalyzed aerobic oxidation of linear aliphatic aldehydes (C2 to C6), a reaction which generates the next lower aldehyde in the triplet state and formic acid. Two main aspects were emphasized in this work: (i ) the dependence of the results of the length of the carbonic chain of the substrate (C2 to C6) and (ii) the possibility of inducing sensitized emission from biological structures (chloroplasts and microsomes). HRP-catalyzed aerobic oxidation of aliphatic aldehydes. Xanthene dyes and micelle-solubilized chlorophyll-a were used to monitor the electronically excited species generated by the peroxidase-catalyzed aerobic oxidation of C2-C6 linear aldehydes. Maximal emission occurs with butanal as substrate and eosine as the fluorescent acceptor. This result is discussed in connection with the fact that the multiple biological effects of short chain aliphatic acids are maximal for butyric acid. Our observations strengthen the case for a possible role of excited state formation in the biological activity butyrate. Energy transfer to chloroplasts Linear aldehydes trigger red emission from chloroplasts. If horseradish peroxidase is also present, the aldehyde is oxidized to the next lower homolog in the triplet state, which in turn sensitizes (directly or indirectly) chlorophyll fluorescence. This phenomenon probably is a case of \"dark luminescence\"; the chlorophyll excited by this process is unable to reduce a Hill acceptor. MIicrosomal luminescence elicited by enzymatic systems that generate triplet species. Microsomes exposed to the propanal/HRP/02 system develop a weak luminescence. The underlying process is distinct from that occuring during lipid peroxidation because the emission intensity peaks at around 560 nm rather than in the red (as would be expected for bimol singlet oxygen emission) and no malonaldehyde is formed. Triplet acetaldehyde appears to be responsible for initiating the process, which in turn leads to excitation of a component of microsomes, possibly a flavoprotein.