6 resultados para Standard and Eurocode design fire curves
em WestminsterResearch - UK
Resumo:
The linguistic situation in Greek-speaking Cyprus has been traditionally described as a textbook case of diglossia à la Ferguson (1959) with Standard Modern Greek (SModGr) being labelled as the High variety and Cypriot Greek (CypGr), the regional ModGr variety of Cyprus, being labelled the Low variety (Arvaniti, 2011; Moschonas, 1996). More recently, however, it has been proposed that the linguistic repertoire available to speakers features an array of forms of CypGr, which is best described as a continuum ranging from basilectal to acrolectal varieties (Katsoyannou et al., 2006; Tsiplakou et al., 2006). The basilectal end encompasses low prestige varieties predominantly spoken in rural areas. The acrolectal end is occupied by the version of SModGr used in the public domain in Cyprus (Arvaniti, 2006/2010). SModGr is known to carry high prestige in Cyprus. Speakers of CypGr describe speakers of the standard as more attractive, more intelligent, more interesting and more educated than speakers of the Cypriot dialect (Papapavlou, 1998). In this paper, I explore the relation between SModGr and CypGr in a diasporic setting, namely, the Greek Cypriot community of London. The United Kingdom is home to a sizeable Greek Cypriot community, whose population is presently estimated to fall between 200,000 and 300,000 individuals (Christodoulou-Pipis, 1991; National Federation of Cypriots in the UK). Similarly to the Cyprus homeland, the members of the Greek Cypriot parikia (‘community’) share a rich linguistic repertoire, which, in addition to varieties of Greek, crucially includes English. As is often the case with diasporas, the parikia does not form a homogeneous speech community in that not all of its members have an equally good command of Greek or even English. Rather, different types of monolingual and bilingual speakers are found including a large number of heritage speakers in the sense of Benmamoun et al. (2013), Montrul (2008, 2015) and Polinsky & Kagan (2007). Twenty British-born heritage speakers of CypGr were interviewed on their attitudes towards the different varieties of Greek. Results indicate that the prestige relation between SModGr and CypGr that holds in Cyprus has been transplanted to the parikia. SModGr is widely perceived as the prestigious variety and is described in positive terms (‘correct’, ‘proper’). The use of CypGr, on the other hand, enjoys covert prestige: it is perceived as an index of solidarity and in-group membership but at the same time is also viewed by heritage speakers as reminiscent of the hardship and lack of education of the generation that brought CypGr to the UK. In certain cases, the use of CypGr by heritage speakers is actively discouraged by the first generation not only in the public domain but also in private domains such as the home. Active discouragement targets both lexical and grammatical variants that are traditionally associated with basilectal varieties of CypGr, and heritage language features, especially the adoption of morphologically adapted loanwords from English. References Arvaniti, Amalia. 2006/2010. Linguistic practices in Cyprus and the emergence of Cypriot Standard Greek. Mediterranean Language Review 17, 15–45. Benmamoun, Elabbas, Silvina Montrul & Maria Polinsky. 2013. Heritage languages and their speakers: opportunities and challenges for linguists. Theoretical Linguistics 39(3/4), 129–181. Christodoulou-Pipis, Irina. 1991. Greek Outside Greece: Language Use by Greek-Cypriots in Britain. Nicosia: Diaspora Books. Ferguson, Charles A. 1959. Diglossia. Word 15(2), 325–340. Katsoyannou, Marianna, Andreas Papapavlou, Pavlos Pavlou & Stavroula Tsiplakou. 2006. Didialektikes koinotites kai glossiko syneches: i periptosi tis kypriakis [Bidialectal communities and linguistic continuum: the case of Cypriot Greek]. In Mark Janse, Brian D. Joseph & Angela Ralli (eds.), Proceedings of the 2nd International Conference of Modern Greek Dialects and Linguistic Theory, Mytilene, Greece, 30 September – 3 October 2004, 156–171. Patras: University of Patras. Montrul, Silvina A. 2008. Incomplete Acquisition in Bilingualism: Re-examining the Age Factor. Amsterdam/Philadelphia: John Benjamins. Montrul, Silvina. 2015. The Acquisition of Heritage Languages. Cambridge: Cambridge University Press. Moschonas, Spiros. 1996. I glossiki dimorfia stin Kypro [Diglossia in Cyprus]. In “Ischyres” – “Astheneis” Glosses stin Evropaiki Enosi: Opseis tou glossikou igemonismou [“Strong” – “Weak” Languages in the European Union: Aspects of Linguistic Imperialism], 121–128. Thessaloniki: Kentro Ellinikis Glossas. Polinsky, Maria & Olga Kagan. 2007. Heritage languages: in the ‘wild’ and in the classroom. Languages and Linguistics Compass 1(5), 368–395. Tsiplakou, Stavroula, Andreas Papapavlou, Pavlos Pavlou & Marianna Katsoyannou. 2006. Levelling, koineization and their implications for bidialectism. In Frans L. Hinskens (Eds.), Language Variation – European Perspectives: Selected Papers from the Third International Conference on Language Variation in Europe (ICLaVE 3), Amsterdam, June 2005, 265–279. Amsterdam/Philadelphia: John Benjamins.
Resumo:
In the Jakarta Metropolitan Region (JMR), the lack of co-ordination and appropriate governance has resulted in paralyzing traffic jams at the metropolitan scale that cannot be resolved by a single government entity. The issue of metropolitan governance is especially crucial here as the JMR lacks an established and formally pre-designed system of governance (e.g., in a constitution or other legal regulations). Instead, it relies on the interaction, coordination and cooperation of a multitude of different stakeholders, ranging from local and regional authorities to private entities and citizens. This chapter offers a discussion on the various governance approaches relating to an appropriate institutional design required for transportation issues at the metropolitan scale. The case used is a regional Bus Rapid Transit (BRT) system as an extension to the metropolitan transport system. Institutional design analysis is applied to the case and three possible improvements - i) a ‘Megapolitan’ concept, ii) a regional spatial plan and iii) inter-local government cooperation; were identified that correspond to current debates on metropolitan governance approaches of regionalism, localism and new regionalism. The findings, which are relevant to similar metropolitan regions, suggest that i) improvements at the meso-level of institutional design are more readily accepted and effective than improvements at the macro-level and ii) that the appropriate institutional design for governing metropolitan transportation in the JMR requires enhanced coordination and cooperation amongst four important actors - local governments, the regional agency, the central government, and private companies.
Resumo:
This paper deals with and details the design and implementation of a low-power; hardware-efficient adaptive self-calibrating image rejection receiver based on blind-source-separation that alleviates the RF analog front-end impairments. Hybrid strength-reduced and re-scheduled data-flow, low-power implementation of the adaptive self-calibration algorithm is developed and its efficiency is demonstrated through simulation case studies. A behavioral and structural model is developed in Matlab as well as a low-level architectural design in VHDL providing valuable test benches for the performance measures undertaken on the detailed algorithms and structures.
Resumo:
The inherent analogue nature of medical ultrasound signals in conjunction with the abundant merits provided by digital image acquisition, together with the increasing use of relatively simple front-end circuitries, have created considerable demand for single-bit beamformers in digital ultrasound imaging systems. Furthermore, the increasing need to design lightweight ultrasound systems with low power consumption and low noise, provide ample justification for development and innovation in the use of single-bit beamformers in ultrasound imaging systems. The overall aim of this research program is to investigate, establish, develop and confirm through a combination of theoretical analysis and detailed simulations, that utilize raw phantom data sets, suitable techniques for the design of simple-to-implement hardware efficient digital ultrasound beamformers to address the requirements for 3D scanners with large channel counts, as well as portable and lightweight ultrasound scanners for point-of-care applications and intravascular imaging systems. In addition, the stability boundaries of higher-order High-Pass (HP) and Band-Pass (BP) Σ−Δ modulators for single- and dual- sinusoidal inputs are determined using quasi-linear modeling together with the describing-function method, to more accurately model the modulator quantizer. The theoretical results are shown to be in good agreement with the simulation results for a variety of input amplitudes, bandwidths, and modulator orders. The proposed mathematical models of the quantizer will immensely help speed up the design of higher order HP and BP Σ−Δ modulators to be applicable for digital ultrasound beamformers. Finally, a user friendly design and performance evaluation tool for LP, BP and HP modulators is developed. This toolbox, which uses various design methodologies and covers an assortment of modulators topologies, is intended to accelerate the design process and evaluation of modulators. This design tool is further developed to enable the design, analysis and evaluation of beamformer structures including the noise analyses of the final B-scan images. Thus, this tool will allow researchers and practitioners to design and verify different reconstruction filters and analyze the results directly on the B-scan ultrasound images thereby saving considerable time and effort.
Resumo:
In this thesis, novel analog-to-digital and digital-to-analog generalized time-interleaved variable bandpass sigma-delta modulators are designed, analysed, evaluated and implemented that are suitable for high performance data conversion for a broad-spectrum of applications. These generalized time-interleaved variable bandpass sigma-delta modulators can perform noise-shaping for any centre frequency from DC to Nyquist. The proposed topologies are well-suited for Butterworth, Chebyshev, inverse-Chebyshev and elliptical filters, where designers have the flexibility of specifying the centre frequency, bandwidth as well as the passband and stopband attenuation parameters. The application of the time-interleaving approach, in combination with these bandpass loop-filters, not only overcomes the limitations that are associated with conventional and mid-band resonator-based bandpass sigma-delta modulators, but also offers an elegant means to increase the conversion bandwidth, thereby relaxing the need to use faster or higher-order sigma-delta modulators. A step-by-step design technique has been developed for the design of time-interleaved variable bandpass sigma-delta modulators. Using this technique, an assortment of lower- and higher-order single- and multi-path generalized A/D variable bandpass sigma-delta modulators were designed, evaluated and compared in terms of their signal-to-noise ratios, hardware complexity, stability, tonality and sensitivity for ideal and non-ideal topologies. Extensive behavioural-level simulations verified that one of the proposed topologies not only used fewer coefficients but also exhibited greater robustness to non-idealties. Furthermore, second-, fourth- and sixth-order single- and multi-path digital variable bandpass digital sigma-delta modulators are designed using this technique. The mathematical modelling and evaluation of tones caused by the finite wordlengths of these digital multi-path sigmadelta modulators, when excited by sinusoidal input signals, are also derived from first principles and verified using simulation and experimental results. The fourth-order digital variable-band sigma-delta modulator topologies are implemented in VHDL and synthesized on Xilinx® SpartanTM-3 Development Kit using fixed-point arithmetic. Circuit outputs were taken via RS232 connection provided on the FPGA board and evaluated using MATLAB routines developed by the author. These routines included the decimation process as well. The experiments undertaken by the author further validated the design methodology presented in the work. In addition, a novel tunable and reconfigurable second-order variable bandpass sigma-delta modulator has been designed and evaluated at the behavioural-level. This topology offers a flexible set of choices for designers and can operate either in single- or dual-mode enabling multi-band implementations on a single digital variable bandpass sigma-delta modulator. This work is also supported by a novel user-friendly design and evaluation tool that has been developed in MATLAB/Simulink that can speed-up the design, evaluation and comparison of analog and digital single-stage and time-interleaved variable bandpass sigma-delta modulators. This tool enables the user to specify the conversion type, topology, loop-filter type, path number and oversampling ratio.