Synthesizable high performance adaptive equaliser and viterbi decoder for the class-IV PRML channel

The design and VLSI implementation of two key components of the class-IV partial response maximum likelihood channel (PR-IV) the adaptive filter and the Viterbi decoder are described. These blocks are implemented using parameterised VHDL modules, from a library of common digital signal processing (DSP) and arithmetic functions. Design studies, based on 0.6 micron 3.3V standard cell processes, indicate that worst case sampling rates of 49 mega-samples per second are achievable for this system, with proportionally high sampling rates for full custom designs and smaller dimension processes. Significant increases in the sampling rate, from 49 MHz to approximately 180 MHz, can be achieved by operating four filter modules in parallel, and this implementation has 50% lower power consumption than a pipelined filter operating at the same speed.

High-Efficiency Harmonic-Peaking Class-EF Power Amplifiers with Enhanced Maximum Operating Frequency

The recently introduced Class-EF power amplifier (PA) has a peak switch voltage lower than that of the Class-E PA. However, the value of the transistor output capacitance at high frequencies is typically larger than the required Class-EF optimum shunt capacitance. Consequently, soft-switching operation that minimizes power dissipation during off-to-on transition cannot be achieved at high frequencies. Two new Class-EF PA variants with transmission-line load networks, namely, third-harmonic-peaking (THP) and fifth-harmonic-peaking (FHP) Class-EF PAs are proposed in this paper. These permit operation at higher frequencies at no expense to other PA figures of merit. Analytical expressions are derived in order to obtain circuit component values, which satisfy the required Class-EF impedances at fundamental frequency, all even harmonics, and the first few odd harmonics as well as simultaneously providing impedance matching to a 50- Ω load. Furthermore, a novel open-circuit and shorted stub arrangement, which has substantial practical benefits, is proposed to replace the normal quarter-wave line connected at the transistor's drain. Using GaN HEMTs, two PA prototypes were built. Measured peak drain efficiency of 91% and output power of 39.5 dBm were obtained at 2.22 GHz for the THP Class-EF PA. The FHP Class-EF PA delivered output power of 41.9 dBm with 85% drain efficiency at 1.52 GHz.

The Pinnacle of Popular Taste?: The Importance of Confessions of a Window Cleaner (1974)

Loathed by critics, the British sexploitation comedy Confessions of a Window Cleaner (1974) was dismissed as tawdry and vulgar yet its massive popular appeal makes it an important indicator of popular taste in the much-maligned 1970s. Using new archival material, this article examines what the film offered and how it was deliberately crafted in order to appeal to a variety of audiences.

“Bound in darkness and idolatry”? Protestant working class underachievement and Unionist hegemony

Over the past decade or more there has been a growing concern at the levels of educational underachievement within loyalist working-class areas of Northern Ireland. The inability of both educational and social policy initiatives over the past decade to improve the situation in any meaningful way has raised important questions concerning how the problem can be tackled more effectively. Placing the issue within the theoretical framework of Gramsci’s hegemony, this paper argues that there is a need to better understand the historical nature of the problem and to recognise the political and social forces that have shaped its existence. It argues that there is a need to move away from explaining Protestant underachievement simply by the availability of jobs in Ulster’s industrial past and to place its roots in the complex battle for social, political, and economic power since the 1801 Act of Union.

In Defiance of Duverger: The Class Cleavage and the Emergence of District-Level Multiparty Systems in Western Europe

At its core, Duverger’s Law—holding that the number of viable parties in first-past-the-post systems should not exceed two—applies primarily at the district level. While the number of parties nationally may exceed two, district-level party system fragmentation should not. Given that a growing body of research shows that district-level party system fragmentation can indeed exceed two in first-past-the-post systems, I explore whether the major alternative explanation for party system fragmentation—the social cleavage approach—can explain such violations of Duverger’s Law. Testing this argument in several West European elections prior to the adoption of proportional representation, I find evidence favouring a social cleavage explanation: with the expansion of the class cleavage, the average district-level party system eventually came to violate the two-party predictions associated with Duverger’s Law. This suggests that sufficient social cleavage diversity may produce multiparty systems in other first-past-the-post systems.

Class Responsibility Assignment (CRA) for Use Case Specification to Sequence Diagrams (UC2SD)

Identifying responsibility for classes in object oriented software design phase is a crucial task. This paper proposes an approach for producing high quality and robust behavioural diagrams (e.g. Sequence Diagrams) through Class Responsibility Assignment (CRA). GRASP or General Responsibility Assignment Software Pattern (or Principle) was used to direct the CRA process when deriving behavioural diagrams. A set of tools to support CRA was developed to provide designers and developers with a cognitive toolkit that can be used when analysing and designing object-oriented software. The tool developed is called Use Case Specification to Sequence Diagrams (UC2SD). UC2SD uses a new approach for developing Unified Modelling Language (UML) software designs from Natural Language, making use of a meta-domain oriented ontology, well established software design principles and established Natural Language Processing (NLP) tools. UC2SD generates a well-formed UML sequence diagrams as output.

Economic Stress and the Great Recession in Ireland: Polarization, Individualization or ‘Middle Class Squeeze’?

Following an unprecedented boom, since 2008 Ireland has experienced a severe economic crisis. Considerable debate persists as to where the heaviest burden of the recession has fallen. Conventional measures of income poverty and inequality have a limited capacity to answer this question. Our analysis, which focuses on economic stress and the mediating role of material deprivation, provides no evidence for individualization or class polarization. Instead we find that while economic stress level are highly stratified in income class and social class terms in both boom and bust periods, the changing impact of class is contingent on life course stage. The affluent income class remained largely insulated from the experience of economic stress. However, it saw its relative advantage overthe income poor class decline at the earlier stage of the life-course. At the other end of the hierarchy, the income poor experienced a relative improvement in their situation in the early life course phases. The precarious income class experienced some improvement in its situation at the earlier life course stages while the outcomes for the middle classes remain unchanged. In the mid-life course stages the precarious and lower middle classes experienced disproportionate increase in their stress levels while at the later life-cycle stage it is the combined middle classes that lost out. Additional effects over time relating to social class are restricted to the deteriorating situation of the petit bourgeoisie at the middle stage of the life-course. The pattern is clearly a good deal more complex that suggested by conventional notions of ‘middle class squeeze’ and points to the distinctive challenges relating to welfare and taxation policy faced by governments in the Great Recession.

A class of almost C_0(K)-C*-algebras

We consider in this paper the family of exponential Lie groups Gn,µ, whose Lie algebra is an extension of the Heisenberg Lie algebra by the reals and whose quotient group by the centre of the Heisenberg group is an ax + b-like group. The C*-algebras of the groups Gn,µ give new examples of almost C0(K)-C*-algebras.