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The purpose of this research is to design a robust high-performance nonlinear multi-input multi-output heating, ventilation and air conditioning (HVAC) system controller for temperature and relative humidity regulation. Buildings are complex systems which are subjected to many unknown disturbances. Further complicating the control problem is the fact that, in practice, buildings and their systems have static nonlinearities such as power saturation that make stability difficult to guarantee. Therefore, in order to overcome these issues, a control system must be designed to be robust (performance insensitive) against uncertainties, static nonlinearities and effectively respond to unknown heat load and moisture disturbances.

A state of the art nonlinear inverse dynamics (NID) technique is combined with a genetic algorithm (GA) optimisation scheme in order to improve robustness against uncertainty in the system's modelling assumptions. The parameter uncertainty problem is addressed by optimising the control system parameters over a specified range of uncertainty. The NID control structure provides further robustness with effective disturbance handling and a stability criteria that holds in the presence of actuator saturation.

The proposed method delivers significantly more energy efficient performance whilst achieving improved thermal comfort when compared with a current industry standard HVAC controller design such as proportional-integral-derivative. The expected excellent response to disturbances is also demonstrated.

This method can easily be extended to account for other parameters with a specified uncertainty range.

This research presents a method of optimised NID controller design which can be easily implemented in real HVAC controllers of building energy management systems with a high degree of confidence to provide high levels of thermal comfort whilst significantly reducing energy usage.

A novel HVAC optimised NID control strategy using the robust inverse dynamics estimation feedback control topology with GA optimisation for improved robustness and tuning over a range of parameter uncertainty is described, designed and its performance benefits shown through simulation studies.

FINANCIAL fears are only less cruel than those of war, and lead men into extravagances which they would repudiate indignantly in their cooler moments. If the doings of the Economy Committee at Manchester in relation to children's libraries, as described in the article by Mr. Lamb in our last issue, are true, we have in them an example of a kind of retrenchment at the expense of the young which we hope is without parallel and will have no imitators. Some reduc‐tion of estimates we hear of from this or that place, but in few has the stupid policy which urges that if we spend nothing we shall all become rich been carried into full effect. Libraries always have suffered in times of crisis, whatever they are; we accept that, though doubtfully; but we do know that the people need libraries.

The purpose of this paper is to develop a conceptual framework which combines the strength of weak ties (SWT) concept with an innovative taxonomy for mitigating principal-agent (P-A) conflicts. The taxonomy highlights the mechanisms through which African women can overcome the obstacles faced when setting up businesses.

The paper discusses the role of “weak ties” networks in entrepreneurial activities and integrates the concept with the key parameters of the P-A paradigm. The aim is to develop a taxonomy (or scorecard) for mitigating the challenges faced by women entrepreneurs in Africa from a P-A perspective. Six P-A parameters are analysed, namely, attitudes towards risk; behaviour-based vs targets-based contracts; asymmetric information; risk-sharing; transaction costs; and verification and monitoring costs.

With the aid of the taxonomy developed in the paper, the authors analyse the channels through which “SWT” networks may impact in mitigating the problems arising from the P-A paradigm. Some implications for women entrepreneurs in Africa are highlighted.

The current conceptual study suggests that the “SWT” concept can be used by African women entrepreneurs to mitigate P-A problems. The authors argue that the original P-A taxonomy developed in the paper fills a conceptual research gap in the existing literature. Embedding the SWT concept within a P-A framework will facilitate further research not only to understand African women entrepreneurs’ attitudes (and responses) towards risk and uncertainty, but this will also facilitate greater understanding of the importance women attach to the role of incentives within their businesses.

The taxonomy presents new insights for understanding the most serious constraints that hinder women entrepreneurs in Africa. The taxonomy will be the basis for a follow-up empirical paper on selected African countries.

The originality of this study lies in the development of an innovative taxonomy which highlights the role of “SWT” social networks towards mitigating the P-A problem among African women entrepreneurs. The paper makes a significant contribution to the literature from a conceptual perspective.

It is now forty years since there appeared H. R. Plomer's first volume Dictionary of the booksellers and printers who were at work in England, Scotland and Ireland from 1641 to 1667. This has been followed by additional Bibliographical Society publications covering similarly the years up to 1775. From the short sketches given in this series, indicating changes of imprint and type of work undertaken, scholars working with English books issued before the closing years of the eighteenth century have had great assistance in dating the undated and in determining the colour and calibre of any work before it is consulted.

The purpose of this paper is to provide a review of the most recent literature concerning document supply and related matters.

The approach is based on the reading of over 150 journals as well as monographs, reports and web sites.

It was found that the fundamental debate on the direction of scholarly publishing continues intensely. Electronic books remain a minority market but the literature at least remains optimistic. The mass digitisation of books continues apace. Open access continues to grow but with continuing and widely differing views on its impact.

The paper represents a useful source of information for librarians and others interested in document supply and related matters.

The purpose of this paper is to review the growing literature examining supply chain risk management (SCRM) and to develop a typology of risks in the supply chain.

The paper draws its insights and conclusions from a review of the literature on supply chain risk, and a synthesis of the broader domain of risk management.

While the literature on SCRM is growing, the literature lacks an organized structure for the sources of supply chain risk. The current paper bridges this gap by synthesizing the diverse literature into a typology of risk sources, consisting of environmental factors, industry factors, organizational factors, problem‐specific factors, and decision‐maker related factors.

The paper devises a typology that can be used by managers to measure and assess the vulnerabilities of their company and supply chain. The typology also provides avenues for future research that further guides practitioners in the management of their supply chain risk portfolio.

SCRM is rapidly developing into a favored research area for academicians as well as practitioners, especially after the attacks of September 11 and the recent array of natural disasters. This paper develops a methodology for structuring academic inquiry in this important research area.

“All things are in a constant state of change”, said Heraclitus of Ephesus. The waters if a river are for ever changing yet the river endures. Every particle of matter is in continual movement. All death is birth in a new form, all birth the death of the previous form. The seasons come and go. The myth of our own John Barleycorn, buried in the ground, yet resurrected in the Spring, has close parallels with the fertility rites of Greece and the Near East such as those of Hyacinthas, Hylas, Adonis and Dionysus, of Osiris the Egyptian deity, and Mondamin the Red Indian maize‐god. Indeed, the ritual and myth of Attis, born of a virgin, killed and resurrected on the third day, undoubtedly had a strong influence on Christianity.