MSAT network architecture

The Mobile Satellite (MSAT) communications system will support mobile voice and data services using circuit switched and packet switched facilities with interconnection to the public switched telephone network and private networks. Control of the satellite network will reside in a Network Control System (NCS) which is being designed to be extremely flexible to provide for the operation of the system initially with one multi-beam satellite, but with capability to add additional satellites which may have other beam configurations. The architecture of the NCS is described. The signalling system must be capable of supporting the protocols for the assignment of circuits for mobile public telephone and private network calls as well as identifying packet data networks. The structure of a straw-man signalling system is discussed

Handling uncertainties in background shapes: the discrete profiling method

A common problem in data analysis is that the functional form, as well as the parameter values, of the underlying model which should describe a dataset is not known a priori. In these cases some extra uncertainty must be assigned to the extracted parameters of interest due to lack of exact knowledge of the functional form of the model. A method for assigning an appropriate error is presented. The method is based on considering the choice of functional form as a discrete nuisance parameter which is profiled in an analogous way to continuous nuisance parameters. The bias and coverage of this method are shown to be good when applied to a realistic example.Comment: Accepted by J.Ins

Dry matter yields and quality of organic lupin/cereal mixtures for wholecrop forage

In view of climate change predictions and the general desirability of increasing the amount of home grown protein, a case exists for the investigation of lupins and lupin/cereal bicrop combinations as wholecrop forage on organic farms. A replicated randomised block trial is described which took place at the Royal Agricultural College, Cirencester, in 2005. This involved spring sown blue, white and yellow lupins, millet, wheat and triticale and lupin/cereal bi-crops. Data for dry matter yields for wholecrop silage, crude protein, MAD fi bre content and estimated ME, are presented for a single harvest. It is concluded that white lupins and white lupin bi-crops with spring wheat or triticale offer the best prospects for a viable wholecrop forage crop in an organic situation

A Robust Age Indicator for Old Stellar Populations

We derive new spectral H_gamma index definitions which are robust age indicators for old and relatively old stellar populations and thus have great potential for solving the age-metallicity degeneracy of galaxy spectra. To study H_gamma as a function of age, metallicity and resolution, we used a new spectral synthesis model which predicts SEDs of single-age, single-metallicity stellar populations at resolution FWHM=1.8A (which can be smoothed to different resolutions), allowing direct measurements of the equivalent widths of particular absorption features. We find that the H_gamma strong age disentangling power strongly depends strongly on the adopted resolution and galaxy velocity dispersion. We propose a system of indices which are completely insensitive to metallicity and stable against resolution, allowing the study of galaxies up to ~300 km/s. Observational spectra of very high S/N and relatively high dispersion, are required to gain this unprecedented age discriminating power. Once such spectra are obtained, accurate and reliable estimates for the luminosity-weighted average stellar ages of these galaxies will become possible for the first time, without assessing their metallicities. We measured this index for two globular clusters, a number of low-luminosity elliptical galaxies and a standard S0 galaxy. We find a large spread in the average stellar ages of a sample of low-luminosity ellipticals. In particular these indices yield 4 Gyr for M32, in agreement with the age provided by an extraordinary fit to the full spectrum of this galaxy that we achieve here.Comment: 22 pages, 4 figures. ApJ, in press. Models and details can be found at http://www.ioa.s.u-tokyo.ac.jp/~vazdekis

Tadpole renormalization and relativistic corrections in lattice NRQCD

We make a comparison of two tadpole renormalization schemes in the context of the quarkonium hyperfine splittings in lattice NRQCD. Improved gauge-field and NRQCD actions are analyzed using the mean-link $u_{0,L}$ in Landau gauge, and using the fourth root of the average plaquette $u_{0,P}$. Simulations are done for $c\bar c$, $b\bar c$, and $b\bar b$ systems. The hyperfine splittings are computed both at leading and at next-to-leading order in the relativistic expansion. Results are obtained at lattice spacings in the range of about 0.14~fm to 0.38~fm. A number of features emerge, all of which favor tadpole renormalization using $u_{0,L}$. This includes much better scaling behavior of the hyperfine splittings in the three quarkonium systems when $u_{0,L}$ is used. We also find that relativistic corrections to the spin splittings are smaller when $u_{0,L}$ is used, particularly for the $c\bar c$ and $b\bar c$ systems. We also see signs of a breakdown in the NRQCD expansion when the bare quark mass falls below about one in lattice units. Simulations with $u_{0,L}$ also appear to be better behaved in this context: the bare quark masses turn out to be larger when $u_{0,L}$ is used, compared to when $u_{0,P}$ is used on lattices with comparable spacings. These results also demonstrate the need to go beyond tree-level tadpole improvement for precision simulations.Comment: 14 pages, 7 figures (minor changes to some phraseology and references

Exploring the Design of Pay-Per-Use Objects in the Construction Domain

Equipment used in the construction domain is often hired in order to reduce cost and maintenance overhead. The cost of hire is dependent on the time period involved and does not take into account the actual use equipment has received. This paper presents our initial investigation into how physical objects augmented with sensing and communication technologies can measure use in order to enable new pay-per-use payment models for equipment hire. We also explore user interaction with pay-per-use objects via mobile devices. The user interactions that take place within our prototype scenario range from simple information access to transactions involving multiple users. This paper presents the design, implementation and evaluation of a prototype pay-per-use system motivated by a real world equipment hire scenario. We also provide insights into the various challenges introduced by supporting a pay-per-use model, including data storage and data security in addition to user interaction issues

Ground Anchors Stabilize Highway Bridge Abutments

Calgary\u27s Glenmore Causeway, constructed in 1962 across the Elbow River, consists of an earthfill embankment with a waterway spanned by a 43 m long bridge, the abutments of which are supported on spread footings founded in the embankment fill. Between the 25 m deep sand and gravel embankment fill and the sub-horizontal bedrock surface is a compressible clay layer up to 5 m thick. To improve abutment stability during peak river flows, 126 post-tensioned Dywidag ground anchors up to 60 m long were installed through the concrete slabs armouring the abutment slopes. Twenty-two anchors were terminated in the embankment fill and the rest were grouted into bedrock. After a series of lift-off tests and anchor retensioning to compensate for ground consolidation, a procedure for predicting the rate of anchor load relaxation was developed. It was concluded the anchors are performing satisfactorily although periodic re-tensioning will be required