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11.
In this paper an adaptive evolutionary algorithm (AEA) for high-level synthesis, resulting in reduction of the power dissipation in CMOS circuits is presented. It enables us to design contemporary electronic circuits/systems with minimisation of the peak and average power consumption, which leads to reduction of the peak and average temperature of the designed chip. Therefore, the reliability of the integrated circuit (IC) can be improved. The results of experiments carried out for the chosen benchmark circuits show that the achieved reduction of power consumption varies from 4 to 52%.  相似文献   
12.
The work described in this paper was aimed at attempts to determine the changes in the acidity of the fatty matter of green coffee beans during storage under tropical conditions, and to relate them to the age of coffee beans, and to the panel assessment of colour and cup-test of the roasted coffee. On the basis of systematic studies a relationship between acid value and coffee age has been found. The coffee beans stored under tropical conditions for up to 4 years showed relatively large increases in acid value, which correlated with average responses of the tasters. In comparison, samples stored under European conditions showed lesser increases in acid value over 5 years, and little change in taste assessment. The determination of acid value is considered to be a useful objective quality control test.  相似文献   
13.
The compensatory-encoding model of reading suggests that experienced readers compensate metacognitively for inefficient reading subcomponents or cognitive resource limitations. For instance, readers with less efficient access to information in working memory are predicted to look back in text more than those with more efficient access to information in working memory. Both groups of readers still have good comprehension. One hundred nine adult readers were measured on the efficiencies of selected reading subcomponents. Texts were read from a computer screen 1 sentence at a time. The extent to which readers looked back in text (reread sentences) was noted. Those with more efficient access to information in verbal working memory looked back less, consistent with the model. Theoretical and educational implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
14.
Investigations of texture changes in aluminium-killed low-carbon unalloyed sheet steels by means of neutron diffraction during uniaxial tensile deformation, deep drawing and biaxial stretching. Calculation of the R-values. Application for the prediction of unfavourable deformation data.  相似文献   
15.
The spallation target model of an accelerator driven system (ADS), consisting of six 5 cm thick and 16 cm in diameter Pb segments, was constructed. Three sets of 17 Bi samples (1/2 inch in diameter and 1 mm thick) were placed in 3 Pb disc-shaped holders inside the target at 5, 10 and 15 cm from its front. After irradiation with 660 MeV proton beam gamma-spectra of radioisotopes produced in Bi were collected several times for each sample with the use of HPGe detectors in order to identify the radioisotopes and to determine their absolute activities. Their spatial distributions were then compared with respective values obtained in the calculations made with the use of FLUKA and/or MCNPX code. A fair agreement with the experiment has been observed.  相似文献   
16.
Flammability, smoke evolution, thermal, and thermomechanical properties of low-density rigid polyurethane foams obtained from different aromatic polyols were investigated. The foams were prepared according to a standard formulation ensuring the same foam phosphorus content. Cellular polyurethanes with the best fire resistance were obtained from polyols containing disubstituted naphthalene and biphenyl rings. A linear equation was proposed to describe the influence of various structural units of the polyurethane (the content of cyclic structures Cc, nitrogen content CN, and crosslinking equivalent Mc) upon its flammability, expressed in terms of its oxygen index (OI) Thermal stability of crosslinked polyurethanes was not found to influence significantly their thermomechanical properties, while crosslink density and the type and quantity of cyclic structures additionally introduced did have a pronounced effect upon these properties.  相似文献   
17.
Standard atomic weights of the elements (1988)  相似文献   
18.
This paper deals with the impact of the top metal electrode on the resistive switching properties of HfO2-based Metal-Insulator-Metal diodes. By screening five different metals as top electrode, Al-Cu-Hf-Pt-Ti, we have demonstrated the feasibility of the resistive switching effect on HfO2. Metals with a low enthalpy of formation of oxides ΔHf0 (Pt and Cu) lead to uni-polar switching whereas easily oxidizable metals with a higher ΔHf0 (Al, Hf and Ti) lead to bipolar switching. Cu-, Hf- and Pt-based devices show a degradation of the top electrode after the forming step by the formation of bubbles whereas such phenomenon was not observed in Al- and Ti-based devices. 200 switching cycles were performed on each device in order to extract the main parameters of the resistive switching effect: ION and IOFF currents in the mA range, ROFF/RON resistance ratio up to 5, Vset and Vreset, voltage levels around 1 V, and powers dissipated during read and write operations in the μW and mW range, respectively. For all systems, the reset process dissipates higher power than the set process. From these results, the Ti top adlayer shows the best performance in terms of stability and resistive switching characteristics.  相似文献   
19.
A comparative study was made between the compact AMS system at the PSI/ETH Laboratory of Ion Beam Physics in Zurich with 0.5 MV terminal voltage and the 5 MV-AMS system at the Scottish Universities Environmental Research Centre (SUERC), Glasgow. Overall 34 urinary samples with 41Ca/40Ca ratios in the range from 4 × 10?11 to 3 × 10?10 were processed to CaF2 and aliquots of the same material were measured on both instruments.Measurements on the compact AMS system were performed in charge state 3+ achieving a transmission of 4% at 1.7 MeV beam energy. Under these conditions a suppression of the interference 41K is virtually impossible. However, samples with an excess of potassium can be identified by a shift of the 41Ca/41K peak in the ΔE ? E histogram of the gas ionization detector employed and a criterion for data rejection can be defined. An overall precision of ~4% and a 41Ca/40Ca background level of 5 × 10?12 have been reached.For studies with higher demands on the detection limit AMS systems like the one at SUERC are attractive: in charge state 5+ and using a gas stripper beam energy of 27 MeV, a transmission of 5%, a 41K suppression factor of ~500 and a 41Ca/40Ca background level of 3 × 10?14 are achieved.We demonstrate that both systems are well suited for large-scale 41Ca biomedical applications.  相似文献   
20.
Application of numerical simulations to improve forging technology for crank shafts is the objective of this work. Thermal–mechanical finite element model combined with closed form equations describing microstructure evolution is used. Simulations of grain size changes in several locations in the volume of the forging were performed. Results of simulations allow to evaluate microstructure of the final product.  相似文献   
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