953 research outputs found
Nonlinear effects in optical data processing Final progress report
Nonlinearity effects in optical data processing, and FORTRAN program for analyzing nonlinearities in spectroscopic photographic plate
The effect of non-linearities on optical correlation processing
Analytical method using series expansion to determine effect of nonlinearities on output of coherent optical correlato
Bibliography on Optical Information and Data Processing
Bibliography on optical information and data processin
Adaptive region growing impulse noise estimator for color images
In this paper, a novel region growing impulse noise estimator for color images is proposed. The aim of this estimator is to distinguish noisy pixels from uncorrupted pixels and subsequently measure the noise proportion efficiently. We use a region growing technique to segment the images into clusters of pixels and propose an adaptive decision scheme to measure the noise proportion. Performance analyses show the proposed scheme outperforms some of the state-of-the art techniques
Development of a gas absorption heat pump for residential applications
Thermally Driven Heat Pumps represent an option to reduce the energy consumption for space heating and
domestic hot water in hard-to-decarbonize buildings without impacting the electrical grid and utilizing the
current and future gaseous energy vectors with high efficiency. Ariston Group and Politecnico di Milano
developed a gas absorption heat pump for the residential market, exploiting design and manufacturing solutions to enable large-scale production and introducing technical features to assure high performance over the entire working range.
In particular, the use of a variable restrictor setup coupled with a patented solution, called “booster”, can reduce the temperature of the generator at high load and high lift conditions, enabling the heat pump to provide the nominal capacity from -22 °C to +40 °C of outdoor air temperature, with supply temperature up to 70 °C.
Moreover, coupled with a specifically designed combustion system, the heat pump can modulate at 1:6 ratio
of its nominal capacity. This feature makes it possible to maintain high efficiency also at part load conditions,
avoiding the on-off operation and making redundant the installation of inertial buffer.
Additionally, an innovative strategy to perform the defrosting of the air-sourced heat exchanger without the
need of acting on the thermodynamic cycle has been developed. This allows defrosting operations extremely
fast, while offering an almost negligible effect on the heat pump performance and substantially no interruption to the heating service and contributing to the elimination of the need to install an inertial buffer.
The thermodynamic core of the appliance was built targeting large scale production. It allows for high specific
capacity (kg/kW) and a small footprint (m2/kW) with the ability to serve nominal capacities ranging from 8 to
15 kW based on the configurations. Laboratory test to assess the performances based on the European Standard
EN 12309 returned a seasonal gas utilization efficiency on the net calorific of 1.50, a seasonal primary energy
ratio of 1.27, and extremely low electrical consumption for the auxiliaries
Iron as recyclable energy carrier: Feasibility study and kinetic analysis of iron oxide reduction
Carbon-free and sustainable energy storage solutions are required to mitigate climate change. One possible solution, especially for stationary applications, could be the storage of energy in metal fuels. Energy can be stored through reduction of the oxide with green hydrogen and be released by combustion. In this work a feasibility study for iron as possible metal fuel considering the complete energy cycle is conducted. On the basis of equilibrium calculations it could be shown that the power-to-power efficiency of the iron/iron oxide cycle is 27 %. As technology development requires a more detailed description of both the reduction and the oxidation, a first outlook is given on the kinetic analysis of the reduction of iron oxides with hydrogen. Thermogravimetric experiments using FeO, FeO and FeO indicate a three-step process for the reduction. The maximum reduction rate can be achieved with a hydrogen content of 25 %. Based on the experimental results a reaction mechanism and accompanied kinetic data were developed for description of FeO reduction with H under varying experimental conditions
Exhumation of the Sierra de Cameros (Iberian Range, Spain): constraints from low-temperature thermochronology
We present new fission-track and (U–Th)/He data from apatite and zircon in order to
reconstruct the exhumation of the Sierra de Cameros, in the northwestern part of Iberian Range,
Spain. Zircon fission-track ages from samples from the depocentre of the basin were reset
during the metamorphic peak at approximately 100 Ma. Detrital apatites from the uppermost sediments
retain fission-track age information that is older than the sediment deposition age, indicating
that these rocks have not exceeded 110 8C. Apatites from deeper in the stratigraphic sequence of
the central part of the basin have fission-track ages of around 40 Ma, significantly younger than
the stratigraphic age, recording the time of cooling after peak metamorphic conditions. Apatite
(U–Th)/He ages in samples from these sediments are 31–40 Ma and record the last period of
cooling during Alpine compression. The modelled thermal history derived from the uppermost
sediments indicates that the thermal pulse associated with peak metamorphism was rapid, and
that the region has cooled continuously to the present. The estimated palaeogeothermal gradient
is around 86 8C km21 and supports a tectonic model with a thick sedimentary fill (c. 8 km) and
explains the origin of the low-grade metamorphism observed in the oldest sediments
Bringing the Laboulbeniales to the 21st century: Enhanced techniques for extraction and PCR amplification of DNA from minute ectoparasitic fungi
One of the most peculiar groups of Ascomycota are the Laboulbeniales. These fungi are characterized by an ectoparasitic life style on arthropods, determinate growth, lack of an asexual stage, high species richness, and intractability to culture. The Laboulbeniales, sister to the Pyxidiophorales, have only recently been assigned their own class, the Laboulbeniomycetes, based on very few ribosomal DNA sequences. So far, DNA isolations and PCR amplifications have proven difficult. Here, we provide details of isolation techniques and the application of commercially available kits that enable efficient and reliable genetic analyses of these peculiar fungi. We provide 43 newly generated Laboulbeniales rDNA sequences, among which are the first published sequences for species in the genera Gloeandromyces, Herpomyces, Laboulbenia, Monoicomyces, and Polyandromyces. DNA extractions were possible using from 1 to 30 thalli from hosts preserved in ethanol (80-100%). In two cases, we successfully isolated DNA from thalli on dried insect collections. Laboulbeniales molecular systematics could be substantially enhanced through these improved methods by allowing more complete sampling of both taxa and gene regions
Oxalobacter formigenes: a potential tool for the treatment of primary hyperoxaluria type 1
Primary hyperoxaluria is characterized by severe urolithiasis, nephrocalcinosis, and early renal failure. As treatment options are scarce, we aimed for a new therapeutic tool using colonic degradation of endogenous oxalate by Oxalobactor formigenes. Oxalobacter was orally administered for 4 weeks as frozen paste (IxOC-2) or as enteric-coated capsules (IxOC-3). Nine patients (five with normal renal function, one after liver–kidney transplantation, and three with renal failure) completed the IxOC-2 study. Seven patients (six with normal renal function and one after liver–kidney transplantation) completed the IxOC-3 study. Urinary oxalate or plasma oxalate in renal failure was determined at baseline, weekly during treatment and for a 2-week follow-up. The patients who showed >20% reduction both at the end of weeks 3 and 4 were considered as responders. Under IxOC-2, three out of five patients with normal renal function showed a 22–48% reduction of urinary oxalate. In addition, two renal failure patients experienced a significant reduction in plasma oxalate and amelioration of clinical symptoms. Under IxOC-3 treatment, four out of six patients with normal renal function responded with a reduction of urinary oxalate ranging from 38.5 to 92%. Although all subjects under IxOC-2 and 4 patients under IxOC-3 showed detectable levels of O. formigenes in stool during treatment, fecal recovery dropped directly at follow up, indicating only transient gastrointestinal-tract colonization. The preliminary data indicate that O. formigenes is safe, leads to a significant reduction of either urinary or plasma oxalate, and is a potential new treatment option for primary hyperoxaluria
GVHD occurrence does not reduce AML relapse following PTCy-based haploidentical transplantation: a study from the ALWP of the EBMT
The association between graft-versus-host disease (GVHD) occurrence and acute myeloid leukemia (AML) relapse in patients treated with HLA-haploidentical allogeneic hematopoietic stem cell transplantation (Haplo-HCT) with post-transplant cyclophosphamide (PTCy)-based GVHD prophylaxis has remained debated. Here, we addressed this issue in patients with active AML at transplantation. 2-year cumulative incidences of relapse and leukemia-free survival (LFS) were 49% and 32.3%, respectively. There were no associations between acute nor chronic GVHD of any grade and lower relapse incidence. However, grade I acute GVHD was associated with better LFS (HR = 0.71, 95% CI 0.51–0.99, P = 0.04). In contrast, grade III–IV acute (HR = 3.09, 95% CI 1.87–5.12, P < 0.0001) as well as extensive chronic (HR = 3.3, 95% CI 1.81–6.04, P = 0.0001) GVHD correlated with higher nonrelapse mortality leading to lower LFS (HR = 1.36, 95% CI 0.99–1.86, P = 0.056 and HR = 1.97, 95% CI 1.35–2.89, P = 0.0004, respectively). In conclusion, these data suggest a dissociation of graft-versus-leukemia effects from GVHD in patients with active AML treated with PTCy-based Haplo-HCT
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