A statistical characterization of shadowed device-to-device communications in an indoor environment

This paper presents the results of a measurement campaign aimed at characterizing and modeling the indoor radio channel between two hypothetical cellular handsets. The device-to-device channel measurements were made at 868 MHz and investigated a number of different everyday scenarios such as the devices being held at the user's heads, placed in a pocket and one of the devices placed on a desktop. The recently proposed shadowed k-μ fading model was used to characterize these channels and was shown to provide a good description of the measured data. It was also evident from the experiments, that the device-to-device communications channel is susceptible to shadowing caused by the human body.

Human body shadowing in cellular device-to-device communications: channel modeling using the shadowed κ−μ fading model

Using device-to-device communications as an underlay for cellular communications will provide an exciting opportunity to increase network capacity as well as improving spectral efficiency. The unique geometry of device-to-device links, where user equipment is often held or carried at low elevation and in close proximity to the human body, will mean that they are particularly susceptible to shadowing events caused not only by the local environment but also by the user's body. In this paper, the shadowed κ - μ fading model is proposed, which is capable of characterizing shadowed fading in wireless communication channels. In this model, the statistics of the received signal are manifested by the clustering of multipath components. Within each of these clusters, a dominant signal component with arbitrary power may exist. The resultant dominant signal component, which is formed by the phasor addition of these leading contributions, is assumed to follow a Nakagami- m distribution. The probability density function, moments, and the moment-generating function are also derived. The new model is then applied to device-to-device links operating at 868 MHz in an outdoor urban environment. It was found that shadowing of the resultant dominant component can vary significantly depending upon the position of the user equipment relative to the body and the link geometry. Overall, the shadowed κ - μ fading model is shown to provide a good fit to the field data as well as providing a useful insight into the characteristics of the received signal.

Autonomous collective agreements as a regulatory device in European labour law:How to read Article 139 EC

This article discusses whether European social partners can derive the competence to autonomously devise European collective labour agreements from Article 139 EC (equals Article III-212 Constitution of Europe). Placing the question in the context of discussions of EU governance and private lawmaking in general, the author starts with a comparative overview of legal conceptions for collective labour agreements in Europe, focusing on three Member States' orders where their effects are not or only partly regulated by state legislation. Based on this comparison, she analyses Article 139(2) and offers a new interpretation of its provisions concerning autonomous implementation of European social partner agreements. She concludes that European social partners do have the competence to agree on a basic agreement stating the rules for European collective bargaining autonomously.

High-radix systolic modular multiplication on reconfigurable hardware

The overall aim of the work presented in this paper has been to develop Montgomery modular multiplication architectures suitable for implementation on modern reconfigurable hardware. Accordingly, novel high-radix systolic array Montgomery multiplier designs are presented, as we believe that the inherent regular structure and absence of global interconnect associated with these, make them well-suited for implementation on modern FPGAs. Unlike previous approaches, each processing element (PE) comprises both an adder and a multiplier. The inclusion of a multiplier in the PE means that the need to pre-compute or store any multiples of the operands is avoided. This also allows very high-radix implementations to be realised, further reducing the amount of clock cycles per modular multiplication, while still maintaining a competitive critical delay. For demonstrative purposes, 512-bit and 1024-bit FPGA implementations using radices of 2(8) and 2(16) are presented. The subsequent throughput rates are the fastest reported to date.

Infrastructure and the Architectures of Modernity in Ireland 1916-2016

At the formation of the new Republic of Ireland, the construction of new infrastructures was seen as an essential element in the building of the new nation, just as the adoption of international style modernism in architecture was perceived as a way to escape the colonial past. Accordingly, infrastructure became the physical manifestation, the concrete identity of these objectives and architecture formed an integral part of this narrative. Moving between scales and from artefact to context, Infrastructure and the Architectures of Modernity in Ireland 1916-2016 provides critical insights and narratives on what is a complex and hitherto overlooked landscape, one which is often as much international as it is Irish. In doing so, it explores the interaction between the universalising and globalising tendencies of modernisation on one hand and the textures of local architectures on the other.

The book shows how the nature of technology and infrastructure is inherently cosmopolitan. Beginning with the building of the heroic Shannon hydro-electric facility at Ardnacrusha by the German firm of Siemens-Schuckert in the first decade of independence, Ireland became a point of varying types of intersection between imported international expertise and local need. Meanwhile, at the other end of the century, by the year 2000, Ireland had become one of the most globalized countries in the world, site of the European headquarters of multinationals such as Google and Microsoft. Climatically and economically expedient to the storing and harvesting of data, Ireland has subsequently become a repository of digital information farmed in large, single-storey sheds absorbed into anonymous suburbs. In 2013, it became the preferred site for Intel to design and develop its new microprocessor chip: the Galileo. The story of the decades in between, of shifts made manifest in architecture and infrastructure from the policies of economic protectionism, to the opening up of the country to direct foreign investment and the embracing of the EU, is one of the influx of technologies and cultural references into a small country on the edges of Europe as Ireland became both a launch-pad and testing ground for a series of aspects of designed modernity.

Punctal plug: a medical device to treat dry eye syndrome and for sustained drug delivery to the eye

Punctal plugs (PPs) are miniature medical implants that were initially developed for the treatment of dry eyes. Since their introduction in 1975, many PPs made from different materials and designs have been developed. PPs, albeit generally successful, suffer from drawbacks such as epiphora and suppurative canaliculitis. To overcome these issues intelligent designs of PPs were proposed (e.g. SmartPLUG™ and Form Fit™). PPs are also gaining interest among pharmaceutical scientists for sustaining drug delivery to the eye. This review aims to provide an overview of PPs for dry eye treatment and drug delivery to treat a range of ocular diseases. It also discusses current challenges in using PPs for ocular diseases.

Out-of-equilibrium thermodynamics of quantum optomechanical systems

We address the out-of-equilibrium thermodynamics of an isolated quantum system consisting of a cavity optomechanical device. We explore the dynamical response of the system when driven out of equilibrium by a sudden quench of the coupling parameter and compute analytically the full distribution of the work generated by the process. We consider linear and quadratic optomechanical coupling, where the cavity field is parametrically coupled to either the position or the square of the position of a mechanical oscillator, respectively. In the former case we find that the average work generated by the quench is zero, whilst the latter leads to a non-zero average value. Through fluctuations theorems we access the most relevant thermodynamical figures of merit, such as the free energy difference and the amount of irreversible work generated. We thus provide a full charac- terization of the out-of-equilibrium thermodynamics in the quantum regime for nonlinearly coupled bosonic modes. Our study is the first due step towards the construction and full quantum analysis of an optomechanical machine working fully out of equilibrium.

Dublin’s ephemeral and imaginary architectures

In 1989, the Irish architectural practice O’Donnell and Tuomey were commissioned to build a temporary pavilion to represent Ireland at the 11 Cities/11 Nations exhibition at Leeuwarden in the Netherlands. Citing Peter Smithson, John Tuomey suggested the pavilion, which drew inspirations from the forms and materials of the modern Irish barn, embodied an intention ‘not just to build but to communicate’. Its subsequent reassembly for the inauguration of the Irish Museum of Modern Art in the courtyard of the seventeenth-century Royal Hospital Kilmainham in Dublin in 1991, drew comparisons between the urban sophistication of this colonial building, its svelte new refit, and the rural expression of O’Donnell + Tuomey’s barn. It was, one critic recently noted, as if ‘a wedding had been crashed by a country cousin who had forgotten to clean his boots’.
It has been argued that temporary or ephemeral pieces of architecture, unburdened by the traditional constraints of firmitas or utilitas, have the ability to offer a concise distillation of meaning and intention. Approaching the qualities of rhetoric, such architectures share similarities with the monument and yet differ in fundamental ways. Their rapid construction in lightweight materials can allow for an almost instantaneous negotiation of zeitgeist. And, unlike the monument, from the outset the space and form of these installations is designed to disappear.
This paper analyses the ephemeral architectures of Dublin in the modern period contextualising their qualities and intentions as they manifest themselves across colonial, post-colonial and contemporary epochs. It finds origins in the theatrical sets of the late eighteenth century and traces their movements into the semi-public sphere of the pleasure garden and finally into the theatre of the streets. It is here that temporary architecture in the city has been at its most potent, allowing the amplification or subversion of the meanings of much larger spaces. Historically, much of Dublin’s most conspicuous instances of ephemeral architecture have been realised as a means of articulating mass spectacle in political, religious or nationalistic events. And while much of this has sought to confirm dominant ideologies, it has also been possible to discern moments of opposition.
The contemporary period, however, has arguably witnessed a shift in ephemeral architectures from explicitly representing ‘positive ideologies’ towards something more oblique or nebulous. This turn towards abstraction in form and space has rendered an especially communicative form of architecture particularly elusive. By examining continuities within the apparent disjuncture between historical and contemporary examples, this paper begins to unpick the language of recent ephemeral architecture in Dublin and situate it within wider global trends where political and economic imperatives are often simultaneously obscured and expressed in public space by a vocabulary of universality. As Jurgen Habermas has suggested, the contemporary value given to the transitory and the ephemeral ‘discloses a longing for an undefiled, immaculate and stable present’.