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51.
We propose a new approach that improves perceptual quality of the separated sources in blind single-channel musical source separation. It uses the advantages of subspace learning based on Non-negative Matrix Factorization (NMF) in which the bases represent the notes. The cost function is formulated in the form of weighted β-divergence by adopting the PEAQ auditory model defined in ITU-R BS.1387 into the source separation. The proposed perceptually weighted factorization scheme is integrated into the Non-negative Matrix Factor 2-D Deconvolution (NMF2D) and Clustered Non-negative Matrix Factorization (CNMF) to overcome the source clustering problem encountered in under-determined source separation. It is shown that the introduced perceptually weighted NMF schemes, named as PW-NMF2D and PW-CNMF, efficiently learn the bases that enable us to apply a simple resynthesis of the musical sources based on the temporal model stored in the encoding matrix. Source separation performance has been reported on musical mixtures where 1–2 dB improvement is achieved in terms of SDR, SIR and SAR compared to the state-of-the-art methods. Performance has also been evaluated by perceptual measures resulting an improvement of 2–5 in OPS, TPS, IPS and APS values. 相似文献
52.
At the ISF (Joining and Welding Institute, RWTH Aachen University) the long-established electron beam (EB) welding process
is investigated to meet the requirements of the field of micro-applications. A modified LEO ZEISS DSM 962 scanning electron
microscope (SEM) is being used as a Micro-EB welding machine. The diameter of the beam in welding mode is about 20 μm, with
a maximum beam power of 6 Watt at 30 kV acceleration voltage. The process-specific advantages, such as the inertia-free movement
of the tool electron beam, the very small beam diameter, the clean room environment which is due to processing in a vacuum
(no shielding gas needed) and the excellent applicability for visual quality control offer the best preconditions for hybrid
micro-assembly purposes. If the technology is down-scaled to a micro-level, physical effects occur whose consequences must
be met with new approaches of solution. Joining of micro-components presupposes optimal contact conditions. If the micro-components
are of a flexible type, those optimal conditions are difficult to implement. The ratio of forces during the joining process
and also the low stiffness of the components which is due to the small dimensions require, on the one hand, the application
of a suitable handling technique or, on the other hand, a specific beam manipulation strategy. Especially in the field of
micro-applications, the possibility to exert influence on the thermal distortion by symmetrical heating and solidification
processes is of particular importance. Therefore, the reproducibility of the welded joints is one of the great challenges
in the field of microwelding. The investigations and developments done at the ISF show successful results in joining stainless
steel sheet materials down to 30 μm thickness and steel wire down to 50 μm in diameter, whereas other materials (Tungsten,
Aluminum, Titanium, Nickel) are under investigation. 相似文献
53.
After a period of general nonspecific symptoms (weakness; nocturnal sweating) for a few days a 29-year-old man suddenly developed a purpura-like rash on both hands and feet ("glove and sock") with mild itching and oedema. A blood count demonstrated leukopenia (2100/microliters) with neutropenia (1100/microliters), thrombocytopenia (81,000/microliters) and reticulocytopenia (1/1000), while haemoglobin content was normal. The bone-marrow showed almost complete reduction of erythropoiesis with the presence of giant proerythroblasts. Granulopoiesis and megakaryopoiesis were unremarkable. Positive tests for IgM and IgG antibodies against parvovirus B19 established the diagnosis of infection with this organism. The rash, blood picture and bone-marrow changes all regressed spontaneously, without any treatment, within a week. The petechial or purpuric "glove and sock" syndrome may be a special form of parvovirus B19 infection. 相似文献
54.
Mechanical theorem proving in projective geometry 总被引:3,自引:0,他引:3
Jürgen Richter-Gebert 《Annals of Mathematics and Artificial Intelligence》1995,13(1-2):139-172
We present an algorithm that is able to confirm projective incidence statements by carrying out calculations in the ring of all formal determinants (brackets) of a configuration. We will describe an implementation of this prover and present a series of examples treated by the prover, includingPappus' andDesargues' theorems, thesixteen point theorem, Saam's theorem, thebundle condition, theuniqueness of a harmonic point andPascal's theorem. 相似文献
55.
K Oette G Kühn A R?mer R Niemann KJ Gundermann R Schumacher 《Canadian Metallurgical Quarterly》1995,45(8):875-879
Essentiale and Lipostabil contain "essential" phospholipids from the soybean, mainly 1,2-dilinoleoyl-phosphatidylcholine (CAS 998-06-1, DLPC) which is considered as the main active ingredient. A single oral dose of d15-DLPC loaded with deuterium 9 times in the choline and 6 times in the linoleic acid of the 1-position was given to volunteers. Sera from 11 blood samples taken within 48 h after application were examined by means of mass spectrometry with regard to d9-choline and d6-linoleic acid in the 1- and 2-position of serum phosphatidylcholines (PC) as well as in the serum triglycerides. d9-choline, i.e. the total of d15-PC and d9-PC, showed maximum values of 5.6% of the total serum PC concentration. Normally, about 1.3% of PC in the human serum is DLPC. Serum 1-linoleoyl-PC was increased by 32-40% after oral application of d15-DLPC. A minor uptake of d6-linoleic acid into the 2-position of serum PC, which is rich in linoleic acid, and into the serum triglycerides was observed with peak values of 2.3% and 6.1%, resp. The uptake of polyunsaturated PC species like DLPC and 1-linoleoyl-PC into the liver after oral application of drugs containing such species in high amounts like "essential" phospholipids with about 50% of DLPC let expect therapeutic effects on membranes into which this special species is incorporated. 相似文献
56.
K. A. Müller 《Journal of Superconductivity and Novel Magnetism》2017,30(10):2707-2709
Doped tungstates exhibit superconductivity as indicated to occur mainly at the surface of the WO3 grains present. To generate bulk 3D superconducting material of doped tungstates, it is proposed to employ the recently discovered UV-generated synthesis of complex oxides from mixed simple oxides by illuminating the mixture with ultraviolet light at modest temperatures, as found in Shengelaya’s group in Tbilisi, and to generate a percolating 3D network of 2D superconducting sheets using the smallest basis oxides as the starting material. The latter procedure was demonstrated recently to be very effective in a collaboration with the present author (Daraselia et al., J. Appl. Phys. 121, 145104, 2017). If this proposition is successful, it would establish the doped tungstates as a second group of HTS besides the copper oxides that could be chosen for certain applications. 相似文献
57.
58.
H. C. Schmelz S. Haffner M. Knupfer G. Krabbes A. Müller G. Reichardt M. S. Golden J. Fink 《Journal of Low Temperature Physics》1996,105(3-4):341-346
We report polarization-dependent angle-resolved photoemission studies of single crystalline Ba2Cu3O4Cl2. This antiferromagnet adopts a layered body-centered tetragonal structure related to that of the cuprates, but with anextra copper site resulting in a plane with Cu3O4 stoichiometry. For the -M direction of the Brillouin zone we observe a dispersive feature with a bandwidth of 400 ±80 meV, which approaches to within 0.9 eV of the Fermi level at (/2,/2). The magnitude of the observed dispersion and its polarization dependence are consistent with its origin as a purely antibonding combination of O2px,y and
atomic orbitals from the cuprate-like CuO2 sub-system, i.e. Zhang-Rice singlets. 相似文献
59.
In the present retrospective investigation, the long-term effects of continuous intrathecal opioid therapy via implantable infusion pump systems were examined in 120 patients with chronic, nonmalignant pain syndromes. The follow-up period was 6 months to 5.7 years (mean 3.4 years +/- 1.3 standard error of the mean). Deafferentation pain and neuropathic pain showed the best long-term results, with 68% and 62% pain reduction (visual analog scale), respectively. The mean morphine dosage initially administered was 2.7 mg/day (range 0.3-12 mg/day); after an average of 3.4 years, it was 4.7 mg/day (range 0.3-12 mg/day). In a long-term observation of 28 patients who received intrathecal morphine for longer than 4 years. 18 patients (64.3%) had a constant dosage history and 10 patients (35.7%) showed an increase in morphine dosage to more than 6 mg/day 1 year after dosage determination. In seven cases, a tolerance developed: in four patients the tolerance was controlled by means of "drug holidays"; but in three patients it was necessary to remove the pump systems. Explantation of the pump system occurred in 22 additional cases for other reasons. Throughout the follow-up period, 74.2% of the patients profited from the intrathecal opiate therapy: the average pain reduction after 6 months was 67.4% and, as of the last follow-up examination, it was 58.1%. Ninety-two percent of the patients were satisfied with the therapy and 81% reported an improvement in their quality of life. The authors' 6-year experience with administration of intrathecal opioid medications for nonmalignant pain should encourage the use of this method in carefully selected patients. 相似文献
60.
A real time control strategy for fuel cell hybrid vehicles is proposed. The objective is to reduce the hydrogen consumption by using an efficient power sharing strategy between the fuel cell system (FCS) and the energy buffer (EB). The energy buffer (battery or supercapacitor) is charge-sustained (no plug-in capabilities). The real time control strategy is derived from a non-causal optimization algorithm based on optimal control theory. The strategy is validated experimentally with a hardware-in-the-loop (HiL) test bench based on a 600 W fuel cell system. 相似文献