778 research outputs found
The Distribution of Software in the European Union After the Decision of the CJEU “UsedSoft GmbH V. Oracle International Corp.†(“UsedSoftâ€)
In “UsedSoft GmbH v. Oracle International Corp.â€, the Europeam Court of Justice opened the way for the sale of "second-hand software" across Europe. The decision UsedSoft gives rise to new data in terms of the content of the right of distribution of a work, including the copy of a computer program, and the issue of exhaustion of the right of distribution of a copy of a computer program. The decision is expected to affect radically the functioning of the EU market of computer programs
Data-driven scenario generation for two-stage stochastic programming
Optimisation under uncertainty has always been a focal point within the Process Systems Engineering (PSE) research agenda. In particular, the efficient manipulation of large amount of data for the uncertain parameters constitutes a crucial condition for effectively tackling stochastic programming problems. In this context, this work proposes a new data-driven Mixed-Integer Linear Programming (MILP) model for the Distribution & Moment Matching Problem (DMP). For cases with multiple uncertain parameters a copula-based simulation of initial scenarios is employed as preliminary step. Moreover, the integration of clustering methods and DMP in the proposed model is shown to enhance computational performance. Finally, we compare the proposed approach with state-of-the-art scenario generation methodologies. Through a number of case studies we highlight the benefits regarding the quality of the generated scenario trees by evaluating the corresponding obtained stochastic solutions
Stable optimisation-based scenario generation via game theoretic approach
Systematic scenario generation (SG) methods have emerged as an invaluable
tool to handle uncertainty towards the efficient solution of stochastic
programming (SP) problems. The quality of SG methods depends on their
consistency to generate scenario sets which guarantee stability on solving SPs
and lead to stochastic solutions of good quality. In this context, we delve
into the optimisation-based Distribution and Moment Matching Problem (DMP) for
scenario generation and propose a game-theoretic approach which is formulated
as a Mixed-Integer Linear Programming (MILP) model. Nash bargaining approach is
employed and the terms of the objective function regarding the statistical
matching of the DMP are considered as players. Results from a capacity planning
case study highlight the quality of the stochastic solutions obtained using
MILP DMP models for scenario generation. Furthermore, the proposed
game-theoretic extension of DMP enhances in-sample and out-of-sample stability
with respect to the challenging problem of user-defined parameters variability
Intrathecal drug delivery systems for the management of chronic non-cancer pain : a systematic review of economic evaluations
Background: Intrathecal drug delivery (ITDD) systems are one of a limited number of management options for chronic non-cancer pain, cancer pain and spasticity. Concerns over their effectiveness and high initial costs led NHS England to decommission ITDD for patients with chronic non-cancer pain. However, the extent to which this decision is in line with existing economic evidence is unclear. The aim of this systematic review is to identify and review the existing evidence on the cost-effectiveness of ITDD for chronic non-cancer pain.
Methods: Full and partial economic evaluations on ITDD were identified through systematic searches in MEDLINE, EMBASE, Web of Science and the National Health Service Centre for Reviews and Dissemination databases. Database searches were complemented by hand searching of reference lists of relevant studies and searches of grey literature. Study selection was carried out by two assessors, independently. Study quality assessment was performed to inform critical appraisal of health economics studies. Data were extracted using a data extraction form developed for this study.
Results: 4464 unique studies were identified, of which seven met the inclusion criteria. With the exception of one study, the studies found ITDD to be either cost-saving or cost-effective compared to conventional medical management. ITDD becomes cost-ineffective in one further study following price year adjustment to 2016.
Conclusions: Study findings show ITDD as not cost-effective only in extremely conservative scenarios. There is limited evidence on the effectiveness of ITDD in non-cancer pain; however, the available economic evidence controverts arguments to refute the treatment on economic grounds
Bluebelle pilot randomised controlled trial of three wound dressing strategies to reduce surgical site infection in primary surgical wounds
Objective Surgical site infection (SSI) affects up to 25% of primary surgical wounds. Dressing strategies may influence SSI risk. The Bluebelle study assessed the feasibility of a multicentre randomised controlled trial (RCT) to evaluate the effectiveness and cost-effectiveness of different dressing strategies to reduce SSI in primary surgical wounds.
Design A pilot, factorial RCT.
Setting Five UK hospitals.
Participants Adults undergoing abdominal surgery with a primary surgical wound.
Interventions Participants were randomised to ‘simple dressing’, ‘glue-as-a-dressing’ or ‘no dressing’, and to the time at which the treatment allocation was disclosed to the surgeon (disclosure time, before or after wound closure).
Primary and secondary outcome measures Feasibility outcomes focused on recruitment, adherence to randomised allocations, reference assessment of SSI and response rates to participant-completed and observer-completed questionnaires to assess SSI (proposed primary outcome for main trial), wound experience and symptoms, and quality of life (EQ-5D-5L).
Results Between March and November 2016, 1115 patients were screened; 699 (73.4%) were eligible and approached, 415 (59.4%) consented and 394 (35.3%) were randomised (simple dressing=133, glue=129 and ‘no dressing’=132). Non-adherence to dressing allocation was 2% (3/133), 6% (8/129) and 15% (20/132), respectively. Adherence to disclosure time was 99% and 86% before and after wound closure, respectively. The overall rate of SSI (reference assessment) was 18.1% (51/281). Response rates to the Wound Healing Questionnaire and other questionnaires ranged from >90% at 4 days to 68% at 4–8 weeks.
Conclusions A definitive RCT of dressing strategies including ‘no dressing’ is feasible. Further work is needed to optimise questionnaire response rates
Investigating the Trade-Off between Design and Operational Flexibility in Continuous Manufacturing of Pharmaceutical Tablets: A Case Study of the Fluid Bed Dryer
Market globalisation, shortened patent lifetimes and the ongoing shift towards personalised medicines exert unprecedented pressure on the pharmaceutical industry. In the push for continuous pharmaceutical manufacturing, processes need to be shown to be agile and robust enough to handle variations with respect to product demands and operating conditions. In this paper we examine the use of operational envelopes to study the trade-off between the design and operational flexibility of the fluid bed dryer at the heart of a tablet manufacturing process. The operating flexibility of this unit is key to the flexibility of the full process and its supply chain. The methodology shows that for the fluid bed dryer case study there is significant effect on flexibility of the process at different drying times with the optimal obtained at 700 s. The flexibility is not affected by the change in volumetric flowrate, but only by the change in temperature. Here the method used a black box model to show how it could be done without access to the full model equation set, as this often needs to be the case in commercial settings
Aqua: Current Status and Future
This document was presented at the NASA Sounder Science Team Meeting held in Greenbelt, MD, September 30-October 2, 2014. The organizers of the meeting plan to post the presentations to a public website
Longwave Band-by-band Cloud Radiative Effect and its Application in GCM Evaluation
The cloud radiative effect (CRE) of each longwave (LW) absorption band of a GCM fs radiation code is uniquely valuable for GCM evaluation because (1) comparing band-by-band CRE avoids the compensating biases in the broadband CRE comparison and (2) the fractional contribution of each band to the LW broadband CRE (f(sub CRE)) is sensitive to cloud top height but largely insensitive to cloud fraction, presenting thus a diagnostic metric to separate the two macroscopic properties of clouds. Recent studies led by the first author have established methods to derive such band ]by ]band quantities from collocated AIRS and CERES observations. We present here a study that compares the observed band-by-band CRE over the tropical oceans with those simulated by three different atmospheric GCMs (GFDL AM2, NASA GEOS-5, and CCCma CanAM4) forced by observed SST. The models agree with observation on the annual ]mean LW broadband CRE over the tropical oceans within +/-1W/sq m. However, the differences among these three GCMs in some bands can be as large as or even larger than +/-1W/sq m. Observed seasonal cycles of f(sub CRE) in major bands are shown to be consistent with the seasonal cycle of cloud top pressure for both the amplitude and the phase. However, while the three simulated seasonal cycles of f(sub CRE) agree with observations on the phase, the amplitudes are underestimated. Simulated interannual anomalies from GFDL AM2 and CCCma CanAM4 are in phase with observed anomalies. The spatial distribution of f(sub CRE) highlights the discrepancies between models and observation over the low-cloud regions and the compensating biases from different bands
Temperature dependence of the charge carrier mobility in gated quasi-one-dimensional systems
The many-body Monte Carlo method is used to evaluate the frequency dependent
conductivity and the average mobility of a system of hopping charges,
electronic or ionic on a one-dimensional chain or channel of finite length. Two
cases are considered: the chain is connected to electrodes and in the other
case the chain is confined giving zero dc conduction. The concentration of
charge is varied using a gate electrode. At low temperatures and with the
presence of an injection barrier, the mobility is an oscillatory function of
density. This is due to the phenomenon of charge density pinning. Mobility
changes occur due to the co-operative pinning and unpinning of the
distribution. At high temperatures, we find that the electron-electron
interaction reduces the mobility monotonically with density, but perhaps not as
much as one might intuitively expect because the path summation favour the
in-phase contributions to the mobility, i.e. the sequential paths in which the
carriers have to wait for the one in front to exit and so on. The carrier
interactions produce a frequency dependent mobility which is of the same order
as the change in the dc mobility with density, i.e. it is a comparably weak
effect. However, when combined with an injection barrier or intrinsic disorder,
the interactions reduce the free volume and amplify disorder by making it
non-local and this can explain the too early onset of frequency dependence in
the conductivity of some high mobility quasi-one-dimensional organic materials.Comment: 9 pages, 8 figures, to be published in Physical Review
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