Two-stage no-wait scheduling models with setup and removal times separated

This paper studies two models of two-stage processing with no-wait in process. The first model is the two-machine flow shop, and the other is the assembly model. For both models we consider the problem of minimizing the makespan, provided that the setup and removal times are separated from the processing times. Each of these scheduling problems is reduced to the Traveling Salesman Problem (TSP). We show that, in general, the assembly problem is NP-hard in the strong sense. On the other hand, the two-machine flow shop problem reduces to the Gilmore-Gomory TSP, and is solvable in polynomial time. The same holds for the assembly problem under some reasonable assumptions. Using these and existing results, we provide a complete complexity classification of the relevant two-stage no-wait scheduling models.

Scheduling for parallel dedicated machines with a single server

This paper examines scheduling problems in which the setup phase of each operation needs to be attended by a single server, common for all jobs and different from the processing machines. The objective in each situation is to minimize the makespan. For the processing system consisting of two parallel dedicated machines we prove that the problem of finding an optimal schedule is NP-hard in the strong sense even if all setup times are equal or if all processing times are equal. For the case of m parallel dedicated machines, a simple greedy algorithm is shown to create a schedule with the makespan that is at most twice the optimum value. For the two machine case, an improved heuristic guarantees a tight worst-case ratio of 3/2. We also describe several polynomially solvable cases of the later problem. The two-machine flow shop and the open shop problems with a single server are also shown to be NP-hard in the strong sense. However, we reduce the two-machine flow shop no-wait problem with a single server to the Gilmore-Gomory traveling salesman problem and solve it in polynomial time. (c) 2000 John Wiley & Sons, Inc.

Experience of using a CFD code for estimating the noise generated by gusts along the sun-roof of a car

The problem to be examined here is the fluctuating pressure distribution along the open cavity of the sun-roof at the top of a car compartment due to gusts passing over the sun-roof. The aim of this test is to investigate the capability of a typical commercial CFD package, PHOENICS, in recognising pressure fluctuations occurring in an important automotive industrial problem. In particular to examine the accuracy of transporting pulsatory gusts traveling along the main flow through the use of finite volume methods with higher order schemes in the numercial solutins of the unsteady compressible Navier-Stokes equations. The Helmholtz equation is used to solve the sound distribution inside the car compartment, resulting from the externally induced fluctuations.

Spaces of observation and obscurity: cinematic prisons of light and dark

In The Eye of Power, Foucault delineated the key concerns surrounding hospital architecture in the latter half of the eighteenth century as being the ‘visibility of bodies, individuals and things'. As such, the ‘new form of hospital' that came to be developed ‘was at once the effect and support of a new type of gaze'. This was a gaze that was not simply concerned with ways of minimising overcrowding or cross-contamination. Rather, this was a surveillance intended to produce knowledge about the pathological bodies contained within the hospital walls. This would then allow for their appropriate classification. Foucault went on to describe how these principles came to be applied to the architecture of prisons. This was exemplified for him in the distinct shape of Bentham's panopticon. This circular design, which has subsequently become an often misused synonym for a contemporary culture of surveillance, was premised on a binary of the seen and the not-seen. An individual observer could stand at the central point of the circle and observe the cells (and their occupants) on the perimeter whilst themselves remaining unseen. The panopticon in its purest form was never constructed, yet it conveys the significance of the production of knowledge through observation that became central to institutional design at this time and modern thought more broadly. What is curious though is that whilst the aim of those late eighteenth century buildings was to produce wellventilated spaces suffused with light, this provoked an interest in its opposite. The gothic movement in literature that was developing in parallel conversely took a ‘fantasy world of stone walls, darkness, hideouts and dungeons…' as its landscape (Vidler, 1992: 162). Curiously, despite these modern developments in prison design, the façade took on these characteristics. The gothic imagination came to describe that unseen world that lay behind the outer wall. This is what Evans refers to as an architectural ‘hoax'. The façade was taken to represent the world within the prison walls and it was the façade that came to inform the popular imagination about what occurred behind it. The rational, modern principles ordering the prison became conflated with the meanings projected by and onto the façade. This confusion of meanings have then been repeated and reenforced in the subsequent representations of the prison. This is of paramount importance since it is the cinematic and televisual representation of the prison, as I argue here and elsewhere, that maintain this erroneous set of meanings, this ‘hoax'.

Rats, floods and flowers: London's Gothicized nature

AUTHOR's OVERVIEW This chapter attempts a definition of London eco-gothic, beginning with an ecocritical reading of the ubiquitous London rat. Following Dracula, popular London gothic has been overrun, from the blunt horror-schlock of James Herbert’s 1970s Rats series to China Miéville’s King Rat. Maud Ellman’s elegant discussion of the modernist rat as a protean figure associated with a ‘panoply of fears and fetishes’, underlines how the rat has always featured in anti-urban discourse: as part of racist representations of immigration; as an expression of fear of disease and poverty; or through a quasi-supernatural anxiety about their indestructible and illimitable nature which makes them a staple feature of post-apocalyptic landscapes. Even so, the London rat is a rather more mundane manifestation of urban eco-gothic than the ‘city wilderness’ metaphors common to representations of New York or Los Angles as identified by eco-critic Andrew White. London’s gothic noses its way out through cracks in the pavements, grows from seeds in suburban gardens or accumulates through the steady drip of rainwater. However, I will suggest, in texts such as Maggie Gee’s The Flood and P. D. James’ Children of Men, London eco-gothic becomes less local and familiar as it responds to global environmental crisis with more dramatic tales of minatorial nature.

Discourse and soul: Jung, literature, science and tragedy as mythical writing

This paper will propose that literature and science, far from being discrete spheres of cultural activity, are, in fact, the cultural expressions of interlocking myths. They therefore overlap and even take each other’s places, as examination of the ‘science’ of C.G. Jung and the ‘art’ of a writer such as John Cowper Powys, will show. ‘Dis-course’, I argue, is the material aspect of the mythical structuring of psychic experience. In the work of Jung and Powys, discourse is the articulation of the soul in the world that spans personal, social, natural and cosmic space. [From the Author]

Legal myth-making: Medea and the legal representation of the feminine ‘other'

The Law operates by, and through, the creation of ideal benchmarks of conduct that are deemed to be representative of the behavioural norm. It is in this sense that it could be contended that the Law utilises, and relies on, myths in the same way as do other disciplines, notably psycho-analysis. It is possible to go even further and argue that the use of a created narrative mythology is essential to the establishment of a defined legal benchmark of behaviour by which the female defendant is assessed, judged and punished. While mythology expresses and symbolizes cultural and political behaviour, it is the Law that embodies and prescribes punitive sanctions. This element represents a powerful literary strand in classical mythology. This may be seen, for instance, in Antigone’s appeal to the Law as justification for her conduct, as much as in Medea’s challenge to the Law though her desire for vengeance. Despite its image of neutral, objective rationality, the Law, in creating and sustaining the ideals of legally-sanctioned conduct, engages in the same literary processes of imagination, reason and emotion that are central to the creation and re-creation of myth. The (re-)presentation of the Medea myth in literature (especially in theatre) and in art, finds its echo in the theatre of the courtroom where wronged women who have refused to passively accept their place, have instead responded with violence. Consequently, the Medea myth, in its depiction of the (un)feminine, serves as a template for the Law’s judgment of ‘conventional’ feminine conduct in the roles of wife and mother. Medea is an image of deviant femininity, as is Lady Macbeth and the countless other un-feminine literary and mythological women who challenge the power of the dominant culture and its ally, the Law. These women stand opposed to the other dominant theme of both literature and Law: the conformist woman, the passive dupe, who are victims of male oppression – women such as Ariadne of Naxos and Tess of the D’Ubervilles – and who are subsequently consumed by the Law, much as Semele is consumed by the fire of Jupiter’s gaze upon her. All of these women, the former as well as the latter, have their real-life counterparts in the pages of the Law Reports. As Fox puts it, “these women have come to bear the weight of the cultural stereotypes and preconceptions about women who kill.”

Human respiration rate estimation using ultra-wideband distributed cognitive radar system

It has been shown that remote monitoring of pulmonary activity can be achieved using ultra-wideband (UWB) systems, which shows promise in home healthcare, rescue, and security applications. In this paper, we first present a multi-ray propagation model for UWB signal, which is traveling through the human thorax and is reflected on the air/dry-skin/fat/muscle interfaces. A geometry-based statistical channel model is then developed for simulating the reception of UWB signals in the indoor propagation environment. This model enables replication of time-varying multipath profiles due to the displacement of a human chest. Subsequently, a UWB distributed cognitive radar system (UWB-DCRS) is developed for the robust detection of chest cavity motion and the accurate estimation of respiration rate. The analytical framework can serve as a basis in the planning and evaluation of future measurement programs. We also provide a case study on how the antenna beamwidth affects the estimation of respiration rate based on the proposed propagation models and system architecture