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111.
Felipe Silva Jardel Silveira Jarbas Silveira César Marcon Fabian Vargas Otávio LimaJr 《Journal of Electronic Testing》2018,34(4):417-433
As the microelectronics technology continuously advances to deep submicron scales, the occurrence of Multiple Cell Upset (MCU) induced by radiation in memory devices becomes more likely to happen. The implementation of a robust Error Correction Code (ECC) is a suitable solution. However, the more complex an ECC, the more delay, area usage and energy consumption. An ECC with an appropriate balance between error coverage and computational cost is essential for applications where fault tolerance is heavily needed, and the energy resources are scarce. This paper describes the conception, implementation, and evaluation of Column-Line-Code (CLC), a novel algorithm for the detection and correction of MCU in memory devices, which combines extended Hamming code and parity bits. Besides, this paper evaluates the variation of the 2D CLC schemes and proposes an additional operation to correct more MCU patterns called extended mode. We compared the implementation cost, reliability level, detection/correction rate and the mean time to failure among the CLC versions and other correction codes, proving the CLCs have high MCU correction efficacy with reduced area, power and delay costs. 相似文献
112.
The obtaining of materials incorporating multiple metal elements is of interest because the combination of various metal cations results in the achievement of new and enhanced properties. Metal-organic frameworks (MOFs) offer a suitable platform to combine multiple metal elements due to their modular nature and highly controllable structure. The incorporation of various metal elements into MOFs might be accomplished by following different synthetic approaches, which in turn determine the way in which the various metal elements are arranged in the framework. In this contribution, we will overview the formation of multi-metal MOFs by the introduction of new metal sites in the organic linkers, or in the inorganic secondary building units through cation exchange process, or one-pot synthesis. 相似文献
113.
CFD as an approach to understand flammable dust 20 L standard test: Effect of the ignition time on the fluid flow 下载免费PDF全文
Daniel Vizcaya Andrés Pinilla Mariangel Amín Nicolás Ratkovich Felipe Munoz Carlos Murillo Nathalie Bardin‐Monnier Olivier Dufaud 《American Institute of Chemical Engineers》2018,64(1):42-54
A computational study based on the Euler–Lagrange approach was developed for the characterization of flammable dusts in the 20 L sphere standard test. The aim of the study was to analyze some parameters that might affect the experimental data (e.g., cold turbulence and particle size). The turbulence of a wheat starch cloud was described with the Detached Eddy Simulation model. Both the pressure of the system and the RMS velocity were compared with the flow patterns established with a particle image velocimetry analysis. It was concluded that the rebound nozzle forms a cloud that is composed by clumps. This fact implies dissimilarities between the local concentrations and the nominal value. Finally, a granulometric analysis established that the mean diameter of the particle size distribution (PSD) decreased by 69% during the dispersion. Thus, it is suggested to consider the PSD at the ignition zone rather than the PSD of the sample. © 2017 American Institute of Chemical Engineers AIChE J, 63: 42–54, 2018 相似文献
114.
Jesus E. Molinar-Solis Felipe Gomez-Castaneda Jose A. Moreno-Cadenas Victor H. Ponce-Ponce 《The Journal of VLSI Signal Processing》2007,49(1):207-216
At present, the Cellular Neural Network (CNN) is a potential parallel structure able to perform image processing tasks in
real-time when is effectively implemented in CMOS technology. The CNN silicon integration success is due mainly to the local
connectivity of processing cells. In this work, an alternative design based on floating-gate MOS inverters is presented, which
uses unipolar signals for solving binary tasks. The approach brings a fast response in a reduced silicon area, as shown through
electrical simulations. A prototype cell in CMOS technology (AMI, 1.2 micron) was fabricated and tested for eight image processing
tasks.
相似文献
Victor H. Ponce-Ponce |
115.
Cervantes FG Heinzel G Marín AF Wand V Steier F Jennrich O Danzmann K 《Applied optics》2007,46(21):4541-4548
We present a real-time differential phase-front detector sensitive to better than 3 mrad rms, which corresponds to a precision of approximately 500 pm. This detector performs a spatially resolving measurement of the phase front of a heterodyne interferometer, with heterodyne frequencies up to approximately 10 kHz. This instrument was developed as part of the research for the Laser Interferometer Space Antenna Technology Package interferometer and will assist in the manufacture of its flight model. Because of the advantages this instrument offers, it also has general applications in optical metrology. 相似文献
116.
A systems biology perspective of wine fermentations 总被引:2,自引:0,他引:2
The yeast Saccharomyces cerevisiae is an important industrial microorganism. Nowadays, it is being used as a cell factory for the production of pharmaceuticals such as insulin, although this yeast has long been utilized in the bakery to raise dough, and in the production of alcoholic beverages, fermenting the sugars derived from rice, wheat, barley, corn and grape juice. S. cerevisiae has also been extensively used as a model eukaryotic system. In the last decade, genomic techniques have revealed important features of its molecular biology. For example, DNA array technologies are routinely used for determining gene expression levels in cells under different physiological conditions or environmental stimuli. Laboratory strains of S. cerevisiae are different from wine strains. For instance, laboratory yeasts are unable to completely transform all the sugar in the grape must into ethanol under winemaking conditions. In fact, standard culture conditions are usually very different from winemaking conditions, where multiple stresses occur simultaneously and sequentially throughout the fermentation. The response of wine yeasts to these stimuli differs in some aspects from laboratory strains, as suggested by the increasing number of studies in functional genomics being conducted on wine strains. In this paper we review the most recent applications of post-genomic techniques to understand yeast physiology in the wine industry. We also report recent advances in wine yeast strain improvement and propose a reference framework for integration of genomic information, bioinformatic tools and molecular biology techniques for cellular and metabolic engineering. Finally, we discuss the current state and future perspectives for using 'modern' biotechnology in the wine industry. 相似文献
117.
Hofmann S Sharma R Ducati C Du G Mattevi C Cepek C Cantoro M Pisana S Parvez A Cervantes-Sodi F Ferrari AC Dunin-Borkowski R Lizzit S Petaccia L Goldoni A Robertson J 《Nano letters》2007,7(3):602-608
We present atomic-scale, video-rate environmental transmission electron microscopy and in situ time-resolved X-ray photoelectron spectroscopy of surface-bound catalytic chemical vapor deposition of single-walled carbon nanotubes and nanofibers. We observe that transition metal catalyst nanoparticles on SiOx support show crystalline lattice fringe contrast and high deformability before and during nanotube formation. A single-walled carbon nanotube nucleates by lift-off of a carbon cap. Cap stabilization and nanotube growth involve the dynamic reshaping of the catalyst nanocrystal itself. For a carbon nanofiber, the graphene layer stacking is determined by the successive elongation and contraction of the catalyst nanoparticle at its tip. 相似文献
118.
Ofelia Mora Jos L Romano Elvira Gonzlez Felipe J Ruiz Armando Shimada 《Journal of the science of food and agriculture》1999,79(2):273-276
Two experiments were conducted to determine the rumen fluid disappearance rates (kd) of β‐carotene, lutein, total carotene and total xanthophyll from lucerne (Medicago sativa) hay, in two ruminant species: Brahman steers (fat‐pigmenting) and Granadine goats (non‐pigmenting). Within species, the in vitro and the in situ methods were compared. The concentration of carotenoid compounds was determined by spectrophotometry and high performance liquid chromatography. The in vitro disappearance trends were linear for all compounds (P<0.01). β‐carotene kd were 0.13 and 0.37; lutein, 0.20 and 0.25; total carotene, 0.20 and 0.62 and total xanthophyll, 0.30 and 0.77 h −1 for steers and goats, respectively. The in situ disappearance trends were quadratic (P<0.01). Dry matter kd were 1.9 and 1.5% h−1; cellular content, 2.0 and 2.3; β‐carotene, 2.5 and 1.2; lutein, 2.5 and 1.5; total carotene, 2.2 and 1.0 and total xanthophyll, 2.1 and 1.1% h−1 for steers and goats, respectively. The large disappearance rates of carotenoids observed in the in situ method vs the virtual absence of disappearance in the in vitro method in both species, can be related to the dry matter and cellular content kd. These results suggest that carotenoids disappear probably by joining the cellular content and not by their direct destruction or by attack from the ruminal microorganisms, and the ruminal disappearance is independent of the species studied. © 1999 Society of Chemical Industry 相似文献
119.
Andoni Rodriguez-Abetxuko Elena Romero-Ben Aitor Ontoria Marcos Heredero Beatriz Martín-García Krishan Kumar Sergio Martín-Saldaña Felipe Conzuelo Ana Beloqui 《Advanced functional materials》2024,34(18):2400479
The inorganic content and the catalytic performance pose metal-loaded enzyme nanoflowers as promising candidates for developing bioelectrodes capable of functioning without the external addition of a redox mediator. However, these protein-inorganic hybrids have yet to be successfully applied in combination with electrode materials. Herein, the synthesis procedure of these bionanomaterials is reproposed to precisely control the morphology, composition, and performance of this particular protein-mineral hybrid, formed by glucose oxidase and cobalt phosphate. This approach aims to enhance the adherence and electron mobility between the enzyme and a carbon electrode. The strategy relies on dressing the protein in a tailored thin nanogel with multivalent chemical motifs. The functional groups of the polymer facilitate the fast protein sequence-independent biomineralization. Furthermore, the engineered enzymes enable the fabrication of robust cobalt-loaded enzyme inorganic hybrids with exceptional protein loads, exceeding 90% immobilization yields. Notably, these engineered biohybrids can be readily deposited onto flat electrode surfaces without requiring chemical pre-treatment. The resulting bioelectrodes are robust and exhibit electrochemical responses even without the addition of a redox mediator, suggesting that cobalt complexes promote electron wiring between the active site of the enzyme and the electrode. 相似文献
120.
Marianela Hazel Álvarez-Hernández Francisco Artés-Hernández Felipe Ávalos-Belmontes Marco Antonio Castillo-Campohermoso Juan Carlos Contreras-Esquivel Janeth Margarita Ventura-Sobrevilla Ginés Benito Martínez-Hernández 《Food and Bioprocess Technology》2018,11(3):511-525
Fruit and vegetables are much appreciated by consumers due to their nutritional values and health-promoting compounds. However, different factors affect the postharvest life of such products, in where ethylene is a major one, even at low concentrations, besides temperature and relative humidity. Therefore, high attention has been focused on the development of effective tools to remove ethylene from the atmosphere surrounding these products during storage or in transit. Potassium permanganate scrubbers are one of the most used technologies to remove ethylene from horticultural products. To facilitate and improve the oxidation process, potassium permanganate has been supported onto inert solid materials of a small particle size. In this review, we aim to provide an outline of the most common materials used as potassium permanganate supports on postharvest treatment and their respective effects on quality aspects of various fresh produce during postharvest life. Vermiculite, activated alumina, zeolite, silica gel, activated carbon and clays are the most popular materials that have been used as a support of potassium permanganate-based ethylene scrubbers. The literature suggests that potassium permanganate supported onto silica gel or zeolite seems to be a promising tool to maintain fruit and vegetables quality attributes for long-term storage. Although vermiculite and activated alumina are the most commonly used materials to reach this goal, not promising results have been reported. 相似文献