3,264 research outputs found
Business Modeling Framework For Personalization In Mobile Business Services
Is presented the structure of a formal framework for personalizationfeatures for mobile business services, which can be used to drive thebusiness modeling of M-business services from a service provider pointof view. It also allows to compute the revenue as linked topersonalization levels and features. A case study has been performedin the area of personalized location based mobile servicespersonalization;individual profiles;location based services;mobile business;mobile services
India: a Case of Fragile Wireless Service and Technology Adoption?
Wireless penetration and the Indian economy have grown significantly over the past few years, but how robust and sustainable is the adoption of wireless services and products? Several papers have discussed India as a wireless service and product market, and sometimes tried to assess quantitative attributes thereof. The present paper aims instead at looking, from a management point of view, at the unique underlying evolution processes, bottlenecks and risks. On specific facets, a comparison is given to adoption indicators in other key markets such as China.For example, just to illustrate highlights of these unique attributes , it is indeed surprising that such a major economy with its very large population has not yet achieved the wireless service usage and mobile terminal penetration ratios of neither an early European adopter ,nor of a recent large scale adopter like China or Russia . India has also been characterised by a surprising regulatory development process quite different from many other contexts, both in terms of its both centralised and regional structure, of very low tariffs providing almost no ROI to investors in a stable situation, and of absence of neutrality across communications technologies. At the same time, a very large fraction of the population has not , for affordability and regional coverage reasons, been able to get the access opportunities of more developed regions , leading to a distribution unbalance which is also a significant opportunity .Also , the wireless service and product adoption pattern in India , specific to communicating services , has so far been in rather sharp contrast with the widely known software and outsourcing services industry evolutions in that country .Therefore it is important to compare the most relevant known wireless service and product adoption theories, to establish from facts whether they apply in the Indian context, and, if not, suggest new or mixed theories able to explain all such facts and cast some light into its likely future structural evolution. It is of high relevance in management to validate if indeed established models apply or not in a significant case like India, just as it is also of high relevance for the main stakeholders to identify methodology able to support their analyses.The paper first provides background information on wireless, fixed, and other operators, on wireless penetration, on telecommunications infrastructure and investments, and on Indian human capital. Thereafter is analyzed in detail the relevance, or not, of five traditional technology adoption models across the Indian user base: the absorption business model, the perceived benefits business model, consumer attitudes, the globalisation business model, and finally the brand management business model. These first analyses are followed by the identification and detailed analysis of five other business models or structural processes, some rather unique to India: the two-tier migration model, large scale imported adoption without a telecommunications infrastructure & terminals industry, unstable adoption with lack of consistent public policies, knowledge sharing and productivity enhancement adoption model, and finally late foreign capital investments into a large emerging market.From the comparison of facts and background data , with these ten wireless service and product adoption models , the paper establishes which are not relevant, and which are too some degree . Furthermore the relevant business models are shown to share, further attributes of sustainability (or not) and dynamic behaviour. This allows concluding that India has had an overall quite fragile adoption and deployment path with growing tensions such as coverage, quality of service and affordability disparities. The model comparison also allows to diagnose the key three structural measures needed to reach a sustainable equilibrium from the business, economic and social points of view.India;Mobile communications;Adoption;Business models;Economic development;Infrastructure;Manufacturing;Mobile terminals;Wireless
An Agent-based Modelling Framework for Driving Policy Learning in Connected and Autonomous Vehicles
Due to the complexity of the natural world, a programmer cannot foresee all
possible situations, a connected and autonomous vehicle (CAV) will face during
its operation, and hence, CAVs will need to learn to make decisions
autonomously. Due to the sensing of its surroundings and information exchanged
with other vehicles and road infrastructure, a CAV will have access to large
amounts of useful data. While different control algorithms have been proposed
for CAVs, the benefits brought about by connectedness of autonomous vehicles to
other vehicles and to the infrastructure, and its implications on policy
learning has not been investigated in literature. This paper investigates a
data driven driving policy learning framework through an agent-based modelling
approaches. The contributions of the paper are two-fold. A dynamic programming
framework is proposed for in-vehicle policy learning with and without
connectivity to neighboring vehicles. The simulation results indicate that
while a CAV can learn to make autonomous decisions, vehicle-to-vehicle (V2V)
communication of information improves this capability. Furthermore, to overcome
the limitations of sensing in a CAV, the paper proposes a novel concept for
infrastructure-led policy learning and communication with autonomous vehicles.
In infrastructure-led policy learning, road-side infrastructure senses and
captures successful vehicle maneuvers and learns an optimal policy from those
temporal sequences, and when a vehicle approaches the road-side unit, the
policy is communicated to the CAV. Deep-imitation learning methodology is
proposed to develop such an infrastructure-led policy learning framework
Instability and new phases of higher-dimensional rotating black holes
It has been conjectured that higher-dimensional rotating black holes become
unstable at a sufficiently large value of the rotation, and that new black
holes with pinched horizons appear at the threshold of the instability. We
search numerically, and find, the stationary axisymmetric perturbations of
Myers-Perry black holes with a single spin that mark the onset of the
instability and the appearance of the new black hole phases. We also find new
ultraspinning Gregory-Laflamme instabilities of rotating black strings and
branes.Comment: 5 pages, 5 figures. The instability of the black hole is argued to
appear at the second zero mode. The first zero mode is not associated to a
new branch of black hole solution
Benchmarking CPUs and GPUs on embedded platforms for software receiver usage
Smartphones containing multi-core central processing units (CPUs) and powerful many-core graphics processing units (GPUs) bring supercomputing technology into your pocket (or into our embedded devices). This can be exploited to produce power-efficient, customized receivers with flexible correlation schemes and more advanced positioning techniques. For example, promising techniques such as the Direct Position Estimation paradigm or usage of tracking solutions based on particle filtering, seem to be very appealing in challenging environments but are likewise computationally quite demanding. This article sheds some light onto recent embedded processor developments, benchmarks Fast Fourier Transform (FFT) and correlation algorithms on representative embedded platforms and relates the results to the use in GNSS software radios. The use of embedded CPUs for signal tracking seems to be straight forward, but more research is required to fully achieve the nominal peak performance of an embedded GPU for FFT computation. Also the electrical power consumption is measured in certain load levels.Peer ReviewedPostprint (published version
Atrial cellular electrophysiological changes in patients with ventricular dysfunction may predispose to AF
<b>Background:</b>
Left ventricular systolic dysfunction (LVSD) is a risk factor for atrial fibrillation (AF), but the atrial cellular electrophysiological mechanisms in humans are unclear.
Objective
This study sought to investigate whether LVSD in patients who are in sinus rhythm (SR) is associated with atrial cellular electrophysiological changes that could predispose to AF.
<b>Methods:</b>
Right atrial myocytes were obtained from 214 consenting patients in SR who were undergoing cardiac surgery. Action potentials or ion currents were measured using the whole-cell-patch clamp technique.
<b>Results:</b>
The presence of moderate or severe LVSD was associated with a shortened atrial cellular effective refractory period (ERP) (209 ± 8 ms; 52 cells, 18 patients vs 233 ± 7 ms; 134 cells, 49 patients; P <0.05); confirmed by multiple linear regression analysis. The left ventricular ejection fraction (LVEF) was markedly lower in patients with moderate or severe LVSD (36% ± 4%, n = 15) than in those without LVSD (62% ± 2%, n = 31; P <0.05). In cells from patients with LVEF †45%, the ERP and action potential duration at 90% repolarization were shorter than in those from patients with LVEF > 45%, by 24% and 18%, respectively. The LVEF and ERP were positively correlated (r = 0.65, P <0.05). The L-type calcium ion current, inward rectifier potassium ion current, and sustained outward ion current were unaffected by LVSD. The transient outward potassium ion current was decreased by 34%, with a positive shift in its activation voltage, and no change in its decay kinetics.
<b>Conclusion:</b>
LVSD in patients in SR is independently associated with a shortening of the atrial cellular ERP, which may be expected to contribute to a predisposition to AF
A DNA element recognised by the molybdenum-responsive transcription factor ModE is conserved in Proteobacteria, green sulphur bacteria and Archaea
BACKGROUND: The transition metal molybdenum is essential for life. Escherichia coli imports this metal into the cell in the form of molybdate ions, which are taken up via an ABC transport system. In E. coli and other Proteobacteria molybdenum metabolism and homeostasis are regulated by the molybdate-responsive transcription factor ModE. RESULTS: Orthologues of ModE are widespread amongst diverse prokaryotes, but not ubiquitous. We identified probable ModE-binding sites upstream of genes implicated in molybdenum metabolism in green sulphur bacteria and methanogenic Archaea as well as in Proteobacteria. We also present evidence of horizontal transfer of nitrogen fixation genes between green sulphur bacteria and methanogenic Archaea. CONCLUSIONS: Whereas most of the archaeal helix-turn-helix-containing transcription factors belong to families that are Archaea-specific, ModE is unusual in that it is found in both Archaea and Bacteria. Moreover, its cognate upstream DNA recognition sequence is also conserved between Archaea and Bacteria, despite the fundamental differences in their core transcription machinery. ModE is the third example of a transcriptional regulator with a binding signal that is conserved in Bacteria and Archaea
Modal curvature-based damage localization in weakly damaged continuous beams
Abstract Modal curvatures have been claimed to contain local information on damage and to be less sensitive to environmental variables than natural frequencies. However, simply using the difference between modal curvatures in the undamaged and damaged states can result into localization errors, due to the complex pattern that this quantity presents when considering broad damages or higher order modes. In this paper, we consider weakly damaged continuous beam and we exploit a perturbative solution of the beam equation of motion to obtain an analytical expression of the modal curvature variations in terms of damage distribution. The solution is then used to introduce a filtering technique of the modal curvature variation and to set up the inverse problem of damage localization based on modal curvatures only. Using numerical examples and experimental tests, we show that modal curvatures can be used for precise damage localization, once properly filtered
Modelling surgical pavilions and a unit of anaesthesia on a Chilean hospital using Specification and Description Language
This work addresses the problem of performing a formal modelling of the
processes related to the surgical pavilions and an anaesthesia unit on a Chilean
hospital. To perform this modelling we used Specification and Description
Language (SDL). The model was very successful in order to document and to
understand the tacit knowledge of the unit and facilitates the simulation.Peer ReviewedPostprint (published version
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