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321.
In this paper we extend Percolation Scheduling (PS) to navigate through a hierarchical version of the Control Flow Graph (CFG)
representation of a VLIW program. This extension retains the completeness of PS by allowing the “normal” PS transformations
to be applied incrementally between adjacent instructions but also enablesnonincremental code motions across arbitrarily large single-entry/single-exit regions of code in constant time. Such nonincremental transformations
eliminate the useless code explosions that would otherwise be caused by using incremental transformations to move operations
through regions containing multiple control paths and, in conjunction with the hierarchical representation of the CFG, provide
a framework for trading offuseful code explosions for increases in parallelism. Simulation results comparing nonincremental with incremental PS are presented.
This work was supported in part by NSF Grant CCR8704367 and ONR Grant N0001486K0215. 相似文献
322.
PAV and the ROC convex hull 总被引:1,自引:0,他引:1
Classifier calibration is the process of converting classifier scores into reliable probability estimates. Recently, a calibration
technique based on isotonic regression has gained attention within machine learning as a flexible and effective way to calibrate
classifiers. We show that, surprisingly, isotonic regression based calibration using the Pool Adjacent Violators algorithm
is equivalent to the ROC convex hull method.
Editor: Johannes Fürnkranz. 相似文献
323.
Laur Calin Adrian Mihalcioiu Alexandru Iuga Lucian Dascalescu 《Particulate Science and Technology》2007,25(2):205-211
The study of the triboelectrification process is the key factor to the successful industrial application of electrostatic separation in the field of plastics recycling. Therefore, the aim of the present work is to evaluate an original device for the laboratory study of this process. The original design of the fluidized bed type triboelectrification device has the following distinctive features: (i) transparent walls to observe the fluidization process and the particles moving in the triboelectrification module; (ii) air distributors with different mesh apertures correlated with granule size; (iii) quick replacement of the triboelectrification Plexiglas chamber with other metallic (aluminium, copper) or nonmetallic chambers (polyvinyl chloride—PVC, polyethylene—PE, and polyethylene terephthalate—PET); (iv) possibility of independent operation, for granule charge measurement or integrated operation, for the electrostatic separation experiments using a free-fall electrostatic separator. The results of charge measurement experiments pointed out the different triboelectric behaviour of two types of granules (polystyrene and low-density polyethylene) in contact with the walls of the device. The electrostatic separation experiments carried out on a binary mixture of mm-size polystyrene/polyethylene granules confirmed the effectiveness of the triboelectrification device. 相似文献
324.
Mazabalo Baneto Alexandru Enesca Yendoubé Lare Koffi Jondo Kossi Napo Anca Duta 《Ceramics International》2014
Sprayed ZnO films were grown on glass substrate at 400 °C using zinc chloride as precursor with different molar concentrations varying from 0.05 to 0.2 M. X-ray diffraction patterns reveal that ZnO films are polycrystalline with hexagonal wurtzite structure with preferred orientation in (002) plane. Optical measurements show that transmittance reaches a maximum value of 95% in the visible region for ZnO films prepared from precursor with 0.05 M concentration. The films obtained from the precursor with 0.1 M concentration have the highest electrical conductivity and photocurrent values. 相似文献
325.
Super-orthogonal space-time trellis codes with eight dimensional phase-shift keying signal constellations 总被引:1,自引:1,他引:0
We propose a new method of designing super-orthogonal space-time trellis codes (SOSTTCS) by labeling each state transition of the trellis diagram with an ordered pair of 2×2 orthogonal matrices instead of only a single 2×2 orthogonal matrix. An 8D instead of a 4D signal constellation is thus used for modulation and the delay elements of the trellis encoder are 4T instead of 2T, where T is the 2D symbol duration. Therefore, at the receiver, the sequence decoding using Viterbi algorithm requires two times less frequent updating of the branch metrics. We investigate by computer simulation the performance of the new sosttcs compared to sosttcs designed by the known method. The frame error rate (fer) and the bit error rate (ber) simulation results show that the performance of the new sosttcs is practically as good as that of the sosttcs of similar complexity designed along classical lines, with the advantage that the number of arithmetic and logic operations performed by the decoder per time unit is smaller, which is crucial in high data-rate applications. 相似文献
326.
Irina Ursachi Aurelia Vasile Adelina Ianculescu Eugeniu Vasile Alexandru Stancu 《Materials Chemistry and Physics》2011
Iron oxide nanoparticles were stabilized within the pores of mesoporous silica MCM-41 amino-functionalized by a sonochemical method. Formation of iron oxide nanoparticles inside the mesoporous channels of amino-functionalized MCM-41 was realized by wet impregnation using iron nitrate, followed by calcinations at 550 °C in air. The effect of functionalization level on structural and magnetic properties of obtained nanocomposites was studied. The resulting materials were characterized by powder X-ray diffraction (XRD), high-resolution transmission electron microscopy and selected area electron diffraction (HRTEM and SAED), vibrating sample and superconducting quantum interface magnetometers (VSM and SQUID) and nitrogen adsorption–desorption isotherms measurements. The HRTEM images reveal that the most of the iron oxide nanoparticles were dispersed inside the mesopores of silica matrix and the pore diameter of the amino-functionalized MCM-41 matrix dictates the particle size of iron oxide nanoparticles. The obtained material possesses mesoporous structure and interesting magnetic properties. Saturation magnetization value of magnetic iron oxide nanopatricles stabilized in MCM-41 amino-functionalized by in situ sonochemical synthesis was 1.84 emu g−1. An important finding is that obtained magnetic nanocomposite materials exhibit enhanced magnetic properties than those of iron oxide/MCM-41 nanocomposite obtained by conventional method. The described method is providing a rather short preparation time and a narrow size distribution of iron oxide nanoparticles. 相似文献
327.
Sharma HS Muresanu DF Patnaik R Stan AD Vacaras V Perju-Dumbrav L Alexandru B Buzoianu A Opincariu I Menon PK Sharma A 《Journal of nanoscience and nanotechnology》2011,11(9):7549-7569
The possibility that cerebrolysin, a mixture of several active fragments of neurotrophic factors and peptides induces neuroprotection following nanoparticles induced exacerbation of brain damage in heat stroke was examined in a rat model. For this purpose, the therapeutic efficacy of Cerebrolysin (2.5 or 5 ml/kg) recommended for stroke treatment was used in comparison with other drugs in standard doses recommended for such therapy in clinical situations e.g., levetiracetam (44 mg/kg), pregabalin (200 mg/kg), topiramate (40 mg/kg,i.p.) and valproate (400 mg/kg). Rats subjected to 4 h heat stress in a biological oxygen demand (BOD) incubator at 38 degrees C (Rel Humid 45-47%; Wind vel 22.4 to 25.6 cm/sec) developed profound behavioral symptoms of heat stroke e.g., hyperthermia, profuse salivation, prostration and gastric ulcerations in the stomach. These rats also exhibited marked brain pathology at this time. Thus, breakdown of the blood-brain barrier (BBB) to proteins associated with brain edema formation could be seen in these heat stressed rats as compared to control groups. The edematous brain areas showed profound neuronal damage and/or distortion in large areas of the neuropil. These pathological symptoms were further exacerbated in Cu or Ag nanoparticles treated group (50-60 nm particle size, 50 mg/kg, i.p./day for 7 days) after identical heat stress on the 8th day. Pretreatment with cerebrolysin (2.5 ml/kg, i.v.) daily for 3 days in normal rats before heat stress significantly reduced the behavioral stress symptoms and the breakdown of the BBB function, edema formation and neuronal injuries. However, the magnitude and intensity of these neuroprotective effects were much less intense in all other drug treated rats after similar heat stress. On the other hand, almost double dose of cerebrolysin (5 ml/kg) was needed to achieve comparable neuroprotection in nanoparticles treated animals after heat stress. Whereas, double dose of all other compounds was much less effective in inducing neuroprotection in nanoparticles treated heat-exposed animals. These observations are the first to show that cerebrolysin exerts the most superior neuroprotective effects in heat stress as compared to other neuroprotective agents on brain pathology in normal and in nanoparticles treated group. Furthermore, cerebrolysin in double dose was the most effective in inducing neuroprotection in nanoparticles treated heat exposed rats on brain pathology as compared to double doses of other drugs. Taken together, our results show that cerebrolysin has the most superior neuroprotective effects on brain pathology in heat stroke in both normal and nanoparticles treated rats as compared to other contemporary neuroprotective agents, not reported earlier. 相似文献
328.
Henrik Andersson Alexandru Rusu Stefan Haller Hans-Erik Nilsson 《Microelectronics Journal》2011,42(1):21-27
This work describes the development of inkjet printed, low-cost memory cards, and complementary pair of memory card reader and card reader/programmer for PCs. This constitutes a complete system that can be used for various applications. The memory cards are manufactured by inkjet printing nano-silver ink on photo paper substrate. The printed memory structures have an initial high resistance that can later be programmed to specific values representing data on the cards, the so called Write Once Read Many (WORM) memories. The memory card reader measures the resistance values of the memory cells and reads it back to the computer by USB connection. Using multiple resistance levels that represent different states it is possible to have a larger number of selectable combinations with fewer physical bits compared to binary coding. This somewhat counters one of the limitations of resistive memory technology that basically each cell needs one physical contact. The number of possible states is related to the resolution of the reader and the stability of the WORM memory. 相似文献
329.
In this paper, we present a solution to the problem of joint tiling and scheduling a given loop nest with uniform data dependencies symbolically. This challenge arises when the size and number of available processors for parallel loop execution is not known at compile time. But still, in order to avoid any overhead of dynamic (run-time) recompilation, a schedule of loop iterations shall be computed and optimized statically. In this paper, it will be shown that it is possible to derive parameterized latency-optimal schedules statically by proposing a two step approach: First, the iteration space of a loop program is tiled symbolically into orthotopes of parametrized extensions. Subsequently, the resulting tiled program is also scheduled symbolically, resulting in a set of latency-optimal parameterized schedule candidates. At run time, once the size of the processor array becomes known, simple comparisons of latency-determining expressions finally steer which of these schedules will be dynamically selected and the corresponding program configuration executed on the resulting processor array so to avoid any further run-time optimization or expensive recompilation. Our theory of symbolic loop parallelization is applied to a number of loop programs from the domains of signal processing and linear algebra. Finally, as a proof of concept, we demonstrate our proposed methodology for a massively parallel processor array architecture called tightly coupled processor array (TCPA) on which applications may dynamically claim regions of processors in the context of invasive computing. 相似文献
330.
Teodora-Irina Adam-Bonci Eduard-Alexandru Bonci Alina-Elena Prvu Andrei-Ioan Herdean Augustin Mo Marian Taulescu Andrei Ungur Raluca-Maria Pop Corina Bocan Alexandru Irimie 《International journal of molecular sciences》2021,22(13)
Asthma oxidative stress disturbances seem to enable supplementary proinflammatory pathways, thus contributing to disease development and severity. The current study analyzed the impact of two types of oral vitamin D (VD) supplementation regimens on the redox balance using a murine model of acute ovalbumin-induced (OVA-induced) asthmatic inflammation. The experimental prevention group received a long-term daily dose of 50 µg/kg (total dose of 1300 µg/kg), whereas the rescue group underwent a short-term daily dose of 100 µg/kg (total dose of 400 µg/kg). The following oxidative stress parameters were analyzed in serum, bronchoalveolar lavage fluid (BALF) and lung tissue homogenate (LTH): total oxidative status, total antioxidant response, oxidative stress index, malondialdehyde and total thiols. Results showed that VD significantly reduced oxidative forces and increased the antioxidant capacity in the serum and LTH of treated mice. There was no statistically significant difference between the two types of VD supplementation. VD also exhibited an anti-inflammatory effect in all treated mice, reducing nitric oxide formation in serum and the expression of nuclear factor kappa B p65 in the lung. In conclusion, VD supplementation seems to exhibit a protective role in oxidative stress processes related to OVA-induced acute airway inflammation. 相似文献