1,386 research outputs found
Z-Axis Optomechanical Accelerometer
We demonstrate a z-axis accelerometer which uses waveguided light to sense
proof mass displacement. The accelerometer consists of two stacked rings (one
fixed and one suspended above it) forming an optical ring resonator. As the
upper ring moves due to z-axis acceleration, the effective refractive index
changes, changing the optical path length and therefore the resonant frequency
of the optical mode. The optical transmission changes with acceleration when
the laser is biased on the side of the optical resonance. This silicon nitride
"Cavity-enhanced OptoMechanical Accelerometer" (COMA) has a sensitivity of 22
percent-per-g optical modulation for our highest optical quality factor (Q_o)
devicesComment: Published in Proceedings of the 25th IEEE International Conference on
Micro Electro Mechanical Systems (MEMS 2012), Paris, France, January 29 - Feb
2, 2012, pp. 615-61
Still vacant after all these years – Evaluating the efficiency of property-led urban regeneration
The author(s) received no financial support for the research, authorship, and/or publication of this article.Peer reviewedPostprin
Modelling & Improving Flow Establishment in RSVP
RSVP has developed as a key component for the evolving Internet, and in particular for the Integrated Services Architecture. Therefore, RSVP performance is crucially important; yet this has been little studied up till now. In this paper, we target one of the most important aspects of RSVP: its ability to establish flows. We first identify the factors influencing the performance of the protocol by modelling the establishment mechanism. Then, we propose a Fast Establishment Mechanism (FEM) aimed at speeding up the set-up procedure in RSVP. We analyse FEM by means of simulation, and show that it offers improvements to the performance of RSVP over a range of likely circumstances
The real interest rate/budget deficit link: international evidence 1973- 82
Interest rates ; Budget deficits
Four Scottish indulgences at Sens
English interest in the great Cistercian abbey of Pontigny was stimulated by the exiles there of two archbishops of Canterbury, Thomas Becket and Stephen Langton.1 As archbishops of Canterbury, Langton and Edmund of Abingdon made gifts to Pontigny abbey in consideration of the welcome given to Becket.2 Edmund did not die at Pontigny, but was a confrater of the community, and the abbot claimed the body, asserting that Edmund had expressed a wish to be buried there. The process of canonisation was rapid.3 After Edmund's canonisation, Henry III sent a chasuble and a chalice for the first celebration of the feast, and granted money to maintain four candles round the saint's shrine.4 In 1254, en route from Gascony to meet Louis IX in Chartres and Paris,5 Henry visited Pontigny, as his brother Richard of Cornwall, who seems to have pressed for canonisation, had done in 1247.6 Archbishop Boniface of Canterbury ordered the celebration of the feast to be observed throughout his province.7 Pope Alexander IV granted a dispensation to allow Englishwomen to enter the precinct of Pontigny abbey on the feast of the translation of the relics of St Edmund8 (women were normally forbidden to enter a Cistercian monastery). Matthew Paris, the greatest English chronicler of the age, wrote a life of the saint.9 English interest continued into the fourteenth century. In 1331 an English priest was given a licence to visit the shrine,10 but it seems likely that the Hundred Years’ War made pilgrimage to Pontigny difficult.11 The indulgences preserved by the abbey reveal an interest in the shrine throughout the Western Church, granted as they were by prelates from Tortosa to Livonia and Estonia, and from Messina to Lübeck.1
Transition to High-Speed Networks — SuperJANET Experience
For the time being, trials to establish the Information Superhighway are booming. In Britain, JANET has provided wide-area computer communication, and has recently been upgraded to SuperJANET, increasing the throughput by a factor of five to 10 Mb/s, with some sites having PDH access at n × 34 Mb/s. In this paper, the technological changes seen from a user perspective are addressed. A multimedia communication-based distance learning project on SuperJANET is introduced and the network performance measurements for this project are presented. These measurements suggest the employment of reservation protocol and packet scheduling. We also provide a mechanism for on-the-fly playback of continuous media
REDO RSVP: Efficient Signalling for Multimedia in the Internet
Alarming reports of performance and scalability problems associated with per-flow reservations, have led many to lose belief in RSVP and the Integrated Services Architecture that relies on it. Because we are convinced of the need for some form of resource reservation, to support multimedia communications in the Internet, we have set about trying to improve RSVP. By careful study of the protocol, we have identified areas for improvement, and propose REDO RSVP, a reduced overhead version that includes a fast establishment mechanism (FEM). In this paper we describe the rationale for REDO RSVP and present a detailed analysis of its features and operations. We also analyse REDO RSVP by means of simulations, and show that it offers improvements to the performance of RSVP
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