1,515,657 research outputs found
Optimal power control in Cognitive MIMO systems with limited feedback
In this paper, the problem of optimal power allocation in Cognitive Radio
(CR) Multiple Input Multiple Output (MIMO) systems is treated. The focus is on
providing limited feedback solutions aiming at maximizing the secondary system
rate subject to a constraint on the average interference caused to primary
communication. The limited feedback solutions are obtained by reducing the
information available at secondary transmitter (STx) for the link between STx
and the secondary receiver (SRx) as well as by limiting the level of available
information at STx that corresponds to the link between the STx and the primary
receiver PRx. Monte Carlo simulation results are given that allow to quanitfy
the performance achieved by the proposed algorithms
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User adoption of a CRM-based information system within a financial services organisation: An empirical analysis
Financial Services firms require processes and systems which can support and maintain customer-related information for the purposes of core business-focussed activity. Specifically within the investment banking sector, the importance and criticality of such customer information underpins the firm’s ability to transact sales, trading and other advisory-based services in an efficient and relevant manner. The design and development of Customer Relationship Management (CRM) systems to address the given external vs. internal customer information touchpoints, therefore provides a vital link between financial services professionals, client data and business processes. In doing so, the input of CRM user requirements is a key step in deriving benefit from such a technology solution. This paper henceforth identifies and details user requirements and experiences of such an information system within a case study company and highlights pertinent issues for the adoption of such systems within the given secto
Optimization on fixed low latency implementation of GBT protocol in FPGA
In the upgrade of ATLAS experiment, the front-end electronics components are
subjected to a large radiation background. Meanwhile high speed optical links
are required for the data transmission between the on-detector and off-detector
electronics. The GBT architecture and the Versatile Link (VL) project are
designed by CERN to support the 4.8 Gbps line rate bidirectional high-speed
data transmission which is called GBT link. In the ATLAS upgrade, besides the
link with on-detector, the GBT link is also used between different off-detector
systems. The GBTX ASIC is designed for the on-detector front-end,
correspondingly for the off-detector electronics, the GBT architecture is
implemented in Field Programmable Gate Arrays (FPGA). CERN launches the
GBT-FPGA project to provide examples in different types of FPGA. In the ATLAS
upgrade framework, the Front-End LInk eXchange (FELIX) system is used to
interface the front-end electronics of several ATLAS subsystems. The GBT link
is used between them, to transfer the detector data and the timing, trigger,
control and monitoring information. The trigger signal distributed in the
down-link from FELIX to the front-end requires a fixed and low latency. In this
paper, several optimizations on the GBT-FPGA IP core are introduced, to achieve
a lower fixed latency. For FELIX, a common firmware will be used to interface
different front-ends with support of both GBT modes: the forward error
correction mode and the wide mode. The modified GBT-FPGA core has the ability
to switch between the GBT modes without FPGA reprogramming. The system clock
distribution of the multi-channel FELIX firmware is also discussed in this
paper
IT and the NHS: Investigating different perspectives of IT using soft systems methodology
The UK NHS National Programme for IT has been criticized for a lack of clinical engagement. This paper uses a soft systems methodology (SSM) analysis of a case study from the use of electronic systems within a National Health Service (NHS) Mental Health Trust in the United Kingdom (UK) to explore the legal and ethical implications of the failure to develop clinical systems which are fit for purpose. Soft systems methodology (SSM) was used as a theoretical model both to derive deeper insights into the survey data and suggest how communication between those producing information and those using it, could be improved. Multiple methods were employed which included a postal survey and participant interviews to triangulate the data The use of SSM reinforced the concept that the national IT programme is based on a 'hard' systems view and does not take local factors (which are related to 'soft systems' thinking) into account. The study found administrative staff to be a crucial link between clinicians and information departments and highlighted the need for a joint-up information strategy and integrated systems. The article concludes with a discussion of the legal and ethical implications of the findings and the lessons for the broader UK national programme. It argues that the failure to deliver systems that are fit for purpose is not value neutral but an ethical issue
Optimal choice of Voluntary traceability as a food risk management tool
Traceability systems are information tools implemented within and between firms in food chains to improve logistics and transparency or to reduce total food safety damage costs. Information about location and condition of products is critical when food safety incidents arise. This paper uses a principal-agent model to investigate the optimal choice of voluntary traceability in terms of precision of information on a given attribute at each link of a food chain. The results suggest that four scenarios may emerge for the supply chain depending on the costs of a system and whether or not the industry can internalize total food safety damages: no traceability, traceability for one link, equal traceability for all links, or different positive traceability levels across all links.Traceability, food safety, principal-agent model, Food Consumption/Nutrition/Food Safety,
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