235 research outputs found
Loss allocation in a distribution system with distributed generation units
In Denmark, a large part of the electricity is produced by wind turbines and combined heat and power plants (CHPs). Most of them are connected to the network through distribution systems. This paper presents a new algorithm for allocation of the losses in a distribution system with distributed generation. The algorithm is based on a reduced impedance matrix of the network and current injections from loads and production units. With the algorithm, the effect of the covariance between production and consumption can be evaluated. To verify the theoretical results, a model of the distribution system in Brønderslev in Northern Jutland, including measurement data, has been studied
T-duality of axial and vector dyonic integrable models
A general construction of affine Non Abelian (NA) - Toda models in terms of
axial and vector gauged two loop WZNW model is discussed. They represent {\it
integrable perturbations} of the conformal -models (with tachyons
included) describing (charged) black hole type string backgrounds. We study the
{\it off-critical} T-duality between certain families of axial and vector type
of integrable models for the case of affine NA- Toda theories with one global
U(1) symmetry. In particular we find the Lie algebraic condition defining a
subclass of {\it T-selfdual} torsionless NA Toda models and their zero
curvature representation.Comment: 20 pages, latex, no figures,improvments in the text of Sects.1,2 and
6;typos corrected,references added, to appear in Ann. of Physics (NY
Dyonic Integrable Models
A class of non abelian affine Toda models arising from the axial gauged
two-loop WZW model is presented. Their zero curvature representation is
constructed in terms of a graded Kac-Moody algebra. It is shown that the
discrete multivacua structure of the potential together with non abelian nature
of the zero grade subalgebra allows soliton solutions with non trivial electric
and topological charges.
The dressing transformation is employed to explicitly construct one and two
soliton solutions and their bound states in terms of the tau functions. A
discussion of the classical spectra of such solutions and the time delays are
given in detail.Comment: Latex 30 pages, corrected some typo
Multicharged Dyonic Integrable Models
We introduce and study new integrable models of A_n^{(1)}-Non-Abelian Toda
type which admit U(1)\otimes U(1) charged topological solitons. They correspond
to the symmetry breaking SU(n+1) \to SU(2)\otimes SU(2)\otimes U(1)^{n-2} and
are conjectured to describe charged dyonic domain walls of N=1 SU(n+1) SUSY
gauge theory in large n limit.
It is shown that this family of relativistic IMs corresponds to the first
negative grade q={-1} member of a dyonic hierarchy of generalized cKP type. The
explicit relation between the 1-soliton solutions (and the conserved charges as
well) of the IMs of grades q=-1 and q=2 is found. The properties of the IMs
corresponding to more general symmetry breaking SU(n+1) \to SU(2)^{\otimes
p}\otimes U(1)^{n-p} as well as IM with global SU(2) symmetries are discussed.Comment: 48pages, latex, v2. typos in eqns. (1.7) and (3.20) corrected, small
improvements in subsection 2.2, new reference added;v3. improvements in text
of Sect. 1,2 and 6; new Sect 7 and new refs. added; version to appear in
Nucl. Phys.
Incidence and risk factors of non-device-associated urinary tract infections in an acute-care hospital
Objective: To update current estimates of non-device-associated pneumonia (ND pneumonia) rates and their frequency relative to ventilator associated pneumonia (VAP), and identify risk factors for ND pneumonia.Design: Cohort study.Setting: Academic teaching hospital.Patients: All adult hospitalizations between 2013 and 2017 were included. Pneumonia (device associated and non-device associated) were captured through comprehensive, hospital-wide active surveillance using CDC definitions and methodology.Results: From 2013 to 2017, there were 163,386 hospitalizations (97,485 unique patients) and 771 pneumonia cases (520 ND pneumonia and 191 VAP). The rate of ND pneumonia remained stable, with 4.15 and 4.54 ND pneumonia cases per 10,000 hospitalization days in 2013 and 2017 respectively (P =.65). In 2017, 74% of pneumonia cases were ND pneumonia. Male sex and increasing age we both associated with increased risk of ND pneumonia. Additionally, patients with chronic bronchitis or emphysema (hazard ratio [HR], 2.07; 95% confidence interval [CI], 1.40-3.06), congestive heart failure (HR, 1.48; 95% CI, 1.07-2.05), or paralysis (HR, 1.72; 95% CI, 1.09-2.73) were also at increased risk, as were those who were immunosuppressed (HR, 1.54; 95% CI, 1.18-2.00) or in the ICU (HR, 1.49; 95% CI, 1.06-2.09). We did not detect a change in ND pneumonia risk with use of chlorhexidine mouthwash, total parenteral nutrition, all medications of interest, and prior ventilation.Conclusion: The incidence rate of ND pneumonia did not change from 2013 to 2017, and 3 of 4 nosocomial pneumonia cases were non-device associated. Hospital infection prevention programs should consider expanding the scope of surveillance to include non-ventilated patients. Future research should continue to look for modifiable risk factors and should assess potential prevention strategies
Incidence and risk factors of non-device-associated pneumonia in an acute-care hospital
Objective: To update current estimates of non-device-associated pneumonia (ND pneumonia) rates and their frequency relative to ventilator associated pneumonia (VAP), and identify risk factors for ND pneumonia. Design: Cohort study. Setting: Academic teaching hospital. Patients: All adult hospitalizations between 2013 and 2017 were included. Pneumonia (device associated and non-device associated) were captured through comprehensive, hospital-wide active surveillance using CDC definitions and methodology. Results: From 2013 to 2017, there were 163,386 hospitalizations (97,485 unique patients) and 771 pneumonia cases (520 ND pneumonia and 191 VAP). The rate of ND pneumonia remained stable, with 4.15 and 4.54 ND pneumonia cases per 10,000 hospitalization days in 2013 and 2017 respectively (P =.65). In 2017, 74% of pneumonia cases were ND pneumonia. Male sex and increasing age we both associated with increased risk of ND pneumonia. Additionally, patients with chronic bronchitis or emphysema (hazard ratio [HR], 2.07; 95% confidence interval [CI], 1.40-3.06), congestive heart failure (HR, 1.48; 95% CI, 1.07-2.05), or paralysis (HR, 1.72; 95% CI, 1.09-2.73) were also at increased risk, as were those who were immunosuppressed (HR, 1.54; 95% CI, 1.18-2.00) or in the ICU (HR, 1.49; 95% CI, 1.06-2.09). We did not detect a change in ND pneumonia risk with use of chlorhexidine mouthwash, total parenteral nutrition, all medications of interest, and prior ventilation. Conclusion: The incidence rate of ND pneumonia did not change from 2013 to 2017, and 3 of 4 nosocomial pneumonia cases were non-device associated. Hospital infection prevention programs should consider expanding the scope of surveillance to include non-ventilated patients. Future research should continue to look for modifiable risk factors and should assess potential prevention strategies
Topological Defects and CMB anisotropies : Are the predictions reliable ?
We consider a network of topological defects which can partly decay into
neutrinos, photons, baryons, or Cold Dark Matter. We find that the degree-scale
amplitude of the cosmic microwave background (CMB) anisotropies as well as the
shape of the matter power spectrum can be considerably modified when such a
decay is taken into account. We conclude that present predictions concerning
structure formation by defects might be unreliable.Comment: 14 pages, accepted for publication in PR
In vivo and in vitro proinflammatory effects of particulate air pollution (PM10).
Epidemiologic studies have reported associations between fine particulate air pollution, especially particles less than 10 mm in diameter (PM10), and the development of exacerbations of asthma and chronic obstructive pulmonary disease. However, the mechanism is unknown. We tested our hypothesis that PM10 induces oxidant stress, causing inflammation and injury to airway epithelium. We assessed the effects of intratracheal instillation of PM10 in rat lungs. The influx of inflammatory cells was measured in bronchoalveolar lavage (BAL). Airspace epithelial permeability was assessed as total protein in bronchoalveolar lavage fluid (BALF) in vivo. The oxidant properties of PM10 were determined by their ability to cause changes in reduced glutathione (GSH) and oxidized glutathione (GSSG). We also compared the effects of PM10 with those of fine (CB) and ultrafine (ufCB) carbon black particles. Six hours after intratracheal instillation of PM10, we noted an influx of neutrophils (up to 15% of total BAL cells) in the alveolar space, increased epithelial permeability, an increase in total protein in BALF from 0.39 +/- 0.01 to 0.62 +/- 0.01 mg/ml (mean +/- SEM) and increased lactate dehydrogenase concentrations in BALF. An even greater inflammatory response was observed after intratracheal instillation of ufCB, but not after CB instillation. PM10 had oxidant activity in vivo, as shown by decreased GSH in BALF (from 0.36 +/- 0.05 to 0.25 +/- 0.01 nmol/ml) after instillation. BAL leukocytes from rats treated with PM10 produced greater amounts of nitric oxide, measured as nitrite (control 3.07 +/- 0.33, treated 4.45 +/- 0.23 mM/1 x 10(6) cells) and tumor necrosis factor alpha (control 21.0 +/- 3.1, treated 179.2 +/- 29.4 unit/1 x 10(6) cells) in culture than BAL leukocytes obtained from control animals. These studies provide evidence that PM10 has free radical activity and causes lung inflammation and epithelial injury. These data support our hypothesis concerning the mechanism for the adverse effects of particulate air pollution on patients with airway diseases
Electrically Charged Topological Solitons
Two new families of T-Dual integrable models of dyonic type are constructed.
They represent specific singular Non-Abelian Affine Toda models
having U(1) global symmetry. Their 1-soliton spectrum contains both neutral and
U(1) charged topological solitons sharing the main properties of 4-dimensional
Yang-Mills-Higgs monopoles and dyons. The semiclassical quantization of these
solutions as well as the exact counterterms and the coupling constant
renormalization are studied.Comment: 40 pages, latex, typos corrected in eq. (2.3), new section on spin of
solitons added, extended discussion on T-duality relation between axial and
vector topological theta terms in new subsection 2.
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