1,850 research outputs found
A simple assessment of housing retrofit policies for the UK: what should succeed the energy company obligation?
Despite the need for large-scale retrofit of UK housing to meet emissions reduction targets, progress to date has been slow and domestic energy efficiency policies have struggled to accelerate housing retrofit processes. There is a need for housing retrofit policies that overcome key barriers within the retrofit sector while maintaining economic viability for customers, funding organizations, and effectively addressing UK emission reductions and fuel poverty targets. In this study, we use a simple assessment framework to assess three policies (the Variable Council Tax, the Variable Stamp Duty Land Tax, and Green Mortgage) proposed to replace the UK’s current major domestic retrofit programme known as the Energy Company Obligation (ECO). We show that the Variable Council Tax and Green Mortgage proposals have the greatest potential for overcoming the main barriers to retrofit policies while maintaining economic viability and contributing to high-level UK targets. We also show that, while none of the assessed schemes are capable of overcoming all retrofit barriers on their own, a mix of all three policies could address most barriers and provide key benefits such as wide coverage of property markets, operation on existing financial infrastructures, and application of a “carrot-and-stick” approach to incentivize retrofit. Lastly, we indicate that the specific support and protection of fuel-poor households cannot be achieved by a mix of these policies and a complementary scheme focused on fuel-poor households is required
Робоча програма і методичні вказівки до самостійного вивчення дисципліни "Основи теорії транспорту"
Гірничовидобувна промисловість України набуває розвитку на базі без-
перервного використання досягнень науково-технічного прогресу, застосування
комплексної механізації та автоматизації всіх процесів виробництва, поліпшен-
ня якісних показників підприємств, підвищення продуктивності й безпеки пра-
ці.Гірничовидобувна промисловість України набуває розвитку на базі без-
перервного використання досягнень науково-технічного прогресу, застосування
комплексної механізації та автоматизації всіх процесів виробництва, поліпшен-
ня якісних показників підприємств, підвищення продуктивності й безпеки пра-
ці
Interleavers and BCH codes for coherent DQPSK systems with laser phase noise
The relatively high phase noise of coherent optical systems poses unique challenges for forward error correction (FEC). In this letter, we propose a novel semianalytical method for selecting combinations of interleaver lengths and binary Bose-Chaudhuri-Hocquenghem (BCH) codes that meet a target post-FEC bit error rate (BER). Our method requires only short pre-FEC simulations, based on which we design interleavers and codes analytically. It is applicable to pre-FEC BER ∼10-3, and any post-FEC BER. In addition, we show that there is a tradeoff between code overhead and interleaver delay. Finally, for a target of 10-5, numerical simulations show that interleaver-code combinations selected using our method have post-FEC BER around 2× target. The target BER is achieved with 0.1 dB extra signal-to-noise ratio
Dimensioning BCH codes for coherent DQPSK systems with laser phase noise and cycle slips
Forward error correction (FEC) plays a vital role in coherent optical systems employing multi-level modulation. However, much of coding theory assumes that additive white Gaussian noise (AWGN) is dominant, whereas coherent optical systems have significant phase noise (PN) in addition to AWGN. This changes the error statistics and impacts FEC performance. In this paper, we propose a novel semianalytical method for dimensioning binary Bose-Chaudhuri-Hocquenghem (BCH) codes for systems with PN. Our method involves extracting statistics from pre-FEC bit error rate (BER) simulations. We use these statistics to parameterize a bivariate binomial model that describes the distribution of bit errors. In this way, we relate pre-FEC statistics to post-FEC BER and BCH codes. Our method is applicable to pre-FEC BER around 10-3 and any post-FEC BER. Using numerical simulations, we evaluate the accuracy of our approach for a target post-FEC BER of 10-5. Codes dimensioned with our bivariate binomial model meet the target within 0.2-dB signal-to-noise ratio
Search for Chargino and Neutralino Production at sqrt(s) = 192-209 GeV at LEP
Approximately 438 pb-1 of e+e- data from the OPAL detector, taken with the
LEP collider running at centre-of-mass energies of 192-209 Gev, are analyzed to
search for evidence of chargino pair production, e+e- -> tilde chi^+_1 tilde
chi^-_1, or neutralino associated production, e+e- -> tilde chi^0_2 tilde
chi^0_1. Limits are set at the 95% confidence level on the product of the
cross-section for the process e+e- -> tilde chi^+_1 tilde chi^-_1 and its
branching ratios to topologies containing jets and missing energy, of jest with
a lepton and missing energy, and on the product of the cross-section for e+e-
-> tilde chi^0_2 tilde chi^0_1 and its branching ratio to jets. R-parity
conservation is assumed throughout this paper. When these results are
interpreted in the context of the Constrained Minimal Supersymmetric Standard
Model, limits are also set on the masses of the tilde chi^+-_1, tilde chi^0_1
and tilde chi^0_2, and regions of the parameter space of the model are ruled
out. Nearly model-independent limits are also set at the 95% confidence level
on sigma(e+e- -> tilde chi^+_1 tilde chi^-_1) with the assumption that each
chargino decays via a W boson, and on sigma(e+e- -> tilde chi^0_2 tilde
chi^0_1) with the tilde chi^0_2 assumed to decay via a Z^0.Comment: 33 pages, 13 figures, Submitted to Eur Phys J.
Initial-state parton shower kinematics for NLO event generators
We are developing a consistent method to combine tree-level event generators
for hadron collision interactions with those including one additional QCD
radiation from the initial-state partons, based on the limited leading-log
(LLL) subtraction method, aiming at an application to NLO event generators. In
this method, a boundary between non-radiative and radiative processes
necessarily appears at the factorization scale (mu_F). The radiation effects
are simulated using a parton shower (PS) in non-radiative processes. It is
therefore crucial in our method to apply a PS which well reproduces the
radiation activities evaluated from the matrix-element (ME) calculations for
radiative processes. The PS activity depends on the applied kinematics model.
In this paper we introduce two models for our simple initial-state leading-log
PS: a model similar to the "old" PYTHIA-PS and a p_T-prefixed model motivated
by ME calculations. PS simulations employing these models are tested using
W-boson production at LHC as an example. Both simulations show a smooth
matching to the LLL-subtracted W + 1 jet simulation in the p_T distribution of
W bosons, and the summed p_T spectra are stable against a variation of mu_F,
despite that the p_T-prefixed PS results in an apparently harder p_T spectrum.Comment: 10 pages, 6 figures; minor changes in the abstract and the text
according to the comments from the refere
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Assessing the discordance rate between local and central HER2 testing in women with locally determined HER2-negative breast cancer.
BackgroundThe importance of human epidermal growth factor receptor 2 (HER2) as a prognostic and predictive marker in invasive breast cancer is well established. Accurate assessment of HER2 status is essential to determine optimal treatment options.MethodsBreast cancer tumor tissue samples from the VIRGO observational cohort tissue substudy that were locally HER2-negative were retested centrally with both US Food and Drug Administration (FDA)-approved immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) assays, using FDA-approved assay cutoffs; results were compared.ResultsOf the 552 unique patient samples centrally retested with local HER2-negative results recorded, tumor samples from 22 (4.0%) patients were determined to be HER2-positive (95% confidence interval [CI] = 2.5%-5.7%). Of these, 18 had been tested locally by only one testing methodology; 15 of 18 were HER2-positive after the central retesting, based on the testing methodology not performed locally. Compared with the 530 patients with centrally confirmed HER2-negative tumors, the 22 patients with centrally determined HER2-positive tumors were younger (median age 56.5 versus 60.0 years) and more likely to have ER/PR-negative tumors (27.3% versus 22.3%). These patients also had shorter median progression-free survival (6.4 months [95% CI = 3.8-15.9 months] versus 9.1 months [95% CI = 8.3-10.3 months]) and overall survival (25.9 months [95% CI = 13.8-not estimable] versus 27.9 months [95% CI = 25.0-32.9 months]).ConclusionsThis study highlights the limitations of employing just one HER2 testing methodology in current clinical practice. It identifies a cohort of patients who did not receive potentially efficacious therapy because their tumor HER2-positivity was not determined by the test initially used. Because of inherent limitations in testing methodologies, it is inadvisable to rely on a single test to rule out potential benefit from HER2-targeted therapy
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