Implementation of a triple modular redundant FPGA based safety critical system for reliable software execution

This paper describes the implementation of a TMR (Triple Modular Redundant) microprocessor system on a FPGA. The system exhibits true redundancy in that three instances of the same processor system (both software and hardware) are executed in parallel. The described system uses software to control external peripherals and a voter is used to output correct results. An error indication is asserted whenever two of the three outputs match or all three outputs disagree. The software has been implemented to conform to a particular safety critical coding guideline/standard which is popular in industry. The system was verified by injecting various faults into it.

A technique for modular logic program refinement

A refinement calculus provides a method for transforming specifications to executable code, maintaining the correctness of the code with respect to its specification. In this paper we introduce modules into a logic programming refinement calculus. Modules allow data types to be grouped together with sets of procedures that manipulate the data types. By placing restrictions on the way a program uses a module, we develop a technique for refining the module so that it uses a more efficient representation of the data type.

Regional foreign direct investment and wage spillovers:plant level evidence from the UK electronics industry

This paper examines the extent to which foreign investment in the UK generates wage spillovers in the domestic sector of the economy using a simultaneous dynamic panel data model and focusing on the electronics sector, possibly the most ‘globalized’ sector of UK manufacturing. It finds evidence that the higher wages paid by foreign firms cause wages in the domestic sector to be bid up. This phenomenon is, however, largely confined to the region where foreign direct investment takes place.

Multinational enterprises and technological effort by local firms:a case study of the Malaysian electronics and electrical industry

It is often assumed that foreign MNEs are the driving force behind technological development in developing economies but it has become evident in recent years that the actions of MNEs in isolation from the domestic economy. The study, therefore, examines the determinants of local firms' decisions to undertake technological effort, not only in isolation, but also in the context of linkages between domestic firms and MNEs. There is evidence that linkages between MNEs and local firms are important in explaining technological effort by local firms but direct technological assistance from MNEs does not seem to play a major role in fostering increased technological effort by local firms.

The impact of foreign direct investment on labour productivity in the Chinese electronics industry

Foreign direct investment (FDI) may have a positive impact on labour productivity in recipient industries through direct introduction of capital, technology and management skills and indirectly through spillover effects on domestic firms. This study uses a model intended to examine the overall effects of inward FDI in the Chinese electronics industry. Official data are used for 41 sub-sectors of the industry in 1996 and 1997 having differing levels of FDI. Labour productivity is modelled as dependent on the degree of foreign presence in the industry and other variables, namely capital intensity, human capital and firm size for scale factors. The econometric results suggest that foreign presence in the industry is associated with higher labour productivity. © 2001 Elsevier Science Ltd.

The impact of the post-1993 economic reforms on Chinese state-owned enterprises:evidence from the electronics industry

Since 1979, China has embarked on a series of economic reform programmes, leading its socialist economy away from a Soviet planning model towards a much greater reliance on the market. In the course of the last twenty years, the Chinese economy has enjoyed a phenomenally high economic growth rate. However, earlier research suggests that Chinese state-owned enterprises remain a financial 'black hole' for the Chinese economy, in spite of various enterprise reform measures. This thesis tries to assess the impact of the reforms after 1993, especially the so-called Modern Enterprise System, on the behaviour and management practices of state firms. The central research question is whether the new rounds of economic reform have changed state firms into commercial entities operating according to market signals, as intended. In order to explore this question, an institutional approach is employed. More specifically, the thesis examines how the behaviour and management practices of state enterprises have changed with changes in the institutional environmental resulting from the introduction of new reform measures and especially the MES. The main evidence used in this research comes from the Chinese electronics industry (CEI). Non-state firms, namely collectives and joint ventures, are involved in the study to provide a benchmark against which changes in the behaviour of state firms in the mid and late 1990s are compared. A comparative statistical analysis shows that state-owned firms, both traditional and corporatised ones, still lag behind collectives and joint ventures in terms of both labour and total factor productivity. The further empirical work of this research consists of a questionnaire survey and case studies that are based on interviews with senior managers of 17 firms in the CEI. The findings of these analyses suggest that there has been little fundamental change in the behaviour pattern of state firms in the 1990s, despite the introduction of the Modern Enterprise System, and that the economic reforms after 1993 so far seem to have failed to transform the state firms into commercial entities operating according to market signals.

A Generic model for the design and analysis of production systems

This dissertation studies the process of operations systems design within the context of the manufacturing organization. Using the DRAMA (Design Routine for Adopting Modular Assembly) model as developed by a team from the IDOM Research Unit at Aston University as a starting point, the research employed empirically based fieldwork and a survey to investigate the process of production systems design and implementation within four UK manufacturing industries: electronics assembly, electrical engineering, mechanical engineering and carpet manufacturing. The intention was to validate the basic DRAMA model as a framework for research enquiry within the electronics industry, where the initial IDOM work was conducted, and then to test its generic applicability, further developing the model where appropriate, within the other industries selected. The thesis contains a review of production systems design theory and practice prior to presenting thirteen industrial case studies of production systems design from the four industry sectors. The results and analysis of the postal survey into production systems design are then presented. The strategic decisions of manufacturing and their relationship to production systems design, and the detailed process of production systems design and operation are then discussed. These analyses are used to develop the generic model of production systems design entitled DRAMA II (Decision Rules for Analysing Manufacturing Activities). The model contains three main constituent parts: the basic DRAMA model, the extended DRAMA II model showing the imperatives and relationships within the design process, and a benchmark generic approach for the design and analysis of each component in the design process. DRAMA II is primarily intended for use by researchers as an analytical framework of enquiry, but is also seen as having application for manufacturing practitioners.

Improved design of all-optical processor for modular arithmetic

A new improved design of an all-optical processor that performs modular arithmetic is presented. The modulo-processor is based on all-optical circuit of interconnected semiconductor optical amplifier logic gates. The design allows processing times of less than 1 µs for 16-bit operation at 10 Gb/s and up to 32-bit operation at 100 Gb/s.

Spectra of modular and small-world matrices

We compute spectra of symmetric random matrices describing graphs with general modular structure and arbitrary inter- and intra-module degree distributions, subject only to the constraint of finite mean connectivities. We also evaluate spectra of a certain class of small-world matrices generated from random graphs by introducing shortcuts via additional random connectivity components. Both adjacency matrices and the associated graph Laplacians are investigated. For the Laplacians, we find Lifshitz-type singular behaviour of the spectral density in a localized region of small |?| values. In the case of modular networks, we can identify contributions of local densities of state from individual modules. For small-world networks, we find that the introduction of short cuts can lead to the creation of satellite bands outside the central band of extended states, exhibiting only localized states in the band gaps. Results for the ensemble in the thermodynamic limit are in excellent agreement with those obtained via a cavity approach for large finite single instances, and with direct diagonalization results.

A modular holistic approach to prosody modelling for Standard Yorùbá speech synthesis

This paper presents a novel prosody model in the context of computer text-to-speech synthesis applications for tone languages. We have demonstrated its applicability using the Standard Yorùbá (SY) language. Our approach is motivated by the theory that abstract and realised forms of various prosody dimensions should be modelled within a modular and unified framework [Coleman, J.S., 1994. Polysyllabic words in the YorkTalk synthesis system. In: Keating, P.A. (Ed.), Phonological Structure and Forms: Papers in Laboratory Phonology III, Cambridge University Press, Cambridge, pp. 293–324]. We have implemented this framework using the Relational Tree (R-Tree) technique. R-Tree is a sophisticated data structure for representing a multi-dimensional waveform in the form of a tree. The underlying assumption of this research is that it is possible to develop a practical prosody model by using appropriate computational tools and techniques which combine acoustic data with an encoding of the phonological and phonetic knowledge provided by experts. To implement the intonation dimension, fuzzy logic based rules were developed using speech data from native speakers of Yorùbá. The Fuzzy Decision Tree (FDT) and the Classification and Regression Tree (CART) techniques were tested in modelling the duration dimension. For practical reasons, we have selected the FDT for implementing the duration dimension of our prosody model. To establish the effectiveness of our prosody model, we have also developed a Stem-ML prosody model for SY. We have performed both quantitative and qualitative evaluations on our implemented prosody models. The results suggest that, although the R-Tree model does not predict the numerical speech prosody data as accurately as the Stem-ML model, it produces synthetic speech prosody with better intelligibility and naturalness. The R-Tree model is particularly suitable for speech prosody modelling for languages with limited language resources and expertise, e.g. African languages. Furthermore, the R-Tree model is easy to implement, interpret and analyse.