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961.
This paper presents the most comprehensive analysis and comparison of the most-known multimedia group and inter-stream synchronization approaches. Several types of multimedia synchronization are identified but only inter-stream and group synchronization algorithms are considered. This is the first survey including group synchronization techniques. A classification of the main synchronization techniques included in most of the analyzed algorithms complements the paper. Finally, a table is presented summarizing the main characteristics of each analyzed algorithm according to those techniques and other critical issues. 相似文献
962.
Olívia Salomé G. P. Soares José J. M. Órfão Manuel Fernando R. Pereira 《Catalysis Letters》2008,126(3-4):253-260
Ten monometallic and 13 bimetallic catalysts supported on activated carbon were assessed, the former in the reduction of nitrate or nitrite and the latter in the nitrate reduction. Under the conditions used, nitrite was shown to be reduced by monometallic catalysts. With exception of Ru, only some of the bimetallic catalysts were able to reduce nitrate. Rh–Cu shows the highest conversion, but Pd–Cu is the most promising catalyst if selectivity into nitrogen is also considered. 相似文献
963.
Fernando Hernndez Sobrino Carlos Rodríguez Monroy 《Renewable & Sustainable Energy Reviews》2009,13(9):2675-2681
For more than a decade we have lived in a period where the so-called “sustainability” is crucial and is motivated primarily by the social awareness of achieving a balance between human development and the conservation of the environment. This philosophy has a direct and inevitable impact on business and politics. Governments have long since been developing standards and encouraging various diverse initiatives whose aim is to defend the environment.In recent times, the global debate on the environment has been centred on CO2 emissions. This gas is the major cause of the “greenhouse effect” and people are more concerned with the idea that the emissions of this gas should be minimized. As a result of this concern, the Kyoto Protocol was enacted and subscribed to by many countries, setting the maximum gas emissions for them.Fossil fuels are a major source of CO2 emissions. In 2003 the European Union (EU) directive 2003/30/EC [2003/30/EC Directive of the European Parliament and the Council—8th may 2003. On the promotion of the use of biofuels or other renewable fuels for transport] was developed with the aim of promoting the use of biofuels as a substitute for diesel or petrol among European Union countries as well as to contribute to fulfilling the commitments on climate change, security of supply in environmentally friendly conditions and the promotion of renewable energy sources.In order to achieve these goals, the directive forces all EU members to ensure that at least 5.75% of all petrol and diesel fuels sold for transport purposes are biofuels before December 31 of 2010. European Union countries have social and economic characteristics unique to themselves. The energy dependence from foreign sources, the features of the agricultural sector or the degree of industrialization varies greatly from one country to another. In this context, it is questionable whether the obligation imposed by this directive applies to achieve uniform and/or identical goals in each of the countries involved and whether the actions of the various governments are also aligned with these goals. 相似文献
964.
Rainald Löhner Juan R. Cebral Fernando F. Camelli Joseph D. Baum Eric L. Mestreau Orlando A. Soto 《Archives of Computational Methods in Engineering》2007,14(3):279-301
Embedded mesh, immersed body or ficticious domain techniques have been used for many years as a way to discretize geometrically
complex domains with structured grids. The use of such techniques within adaptive, unstructured grid solvers is relatively
recent. The combination of body-fitted functionality for some portion of the domain, together with embedded mesh or immersed
body functionality for another portion of the domain offers great advantages, which are increasingly being exploited. The
present paper reviews the methodology from an implementational perspective. 相似文献
965.
Fernando L. Taracena 《Quality Engineering》2006,18(1):33-37
Industry competitiveness requires the best possible quality-price combination; therefore, cost analysis is usually required at the design stages. Off-line quality control methods are conducted at the product and process design stages to improve manufacturing costs and quality of the product. An economic analysis is proposed in this article that can be carried out along with the known parameter design methods. The economic analysis in the experimental design does not add experimental costs and shows potential savings. The model minimizes the total expected quality cost, which includes the cost of using a set of factor levels and its expected quality loss. 相似文献
966.
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968.
969.
Distributed video coding (DVC) is an emerging video coding technology that utilises the distributed source coding principles to build very low cost video encoders, yet with remarkable error resilience. In the most common DVC framework, the reconstruction function plays a vital role that has a direct impact on the output video quality. In this study, a novel algorithm is proposed for the reconstruction function, particularly focusing on a unidirectional DVC architecture. The proposed technique exploits the variations of the bit error rate of the Wyner-Ziv decoded bit stream and the assumed noise model in the side information stream. The simulation results show that the proposed algorithm yields a significant improvement of the objective and subjective video quality at no additional bit rate cost. 相似文献
970.
Emmanuel Pina-Jimnez Fernando Calzada Elihú Bautista Rosa María Ordoez-Razo Claudia Velzquez Elizabeth Barbosa Normand García-Hernndez 《International journal of molecular sciences》2021,22(19)
Sesquiterpene lactones are of pharmaceutical interest due their cytotoxic and antitumor properties, which are commonly found within plants of several genera from the Asteraceae family such as the Decachaeta genus. From Decachaeta incompta four heliangolide, namely incomptines A-D have been isolated. In this study, cytotoxic properties of incomptine A (IA) were evaluated on four lymphoma cancer cell lines: U-937, Farage, SU-DHL-2, and REC-1. The type of cell death induced by IA and its effects on U-937 cells were analyzed based on its capability to induce apoptosis and produce reactive oxygen species (ROS) through flow cytometry with 4′,6-diamidino-2-phenylindole staining, dual annexin V/DAPI staining, and dichlorofluorescein 2′,7′-diacetate, respectively. A differential protein expression analysis study was carried out by isobaric tags for relative and absolute quantitation (iTRAQ) through UPLC-MS/MS. Results reveal that IA exhibited cytotoxic activity against the cell line U-937 (CC50 of 0.12 ± 0.02 μM) and the incubation of these cells in presence of IA significantly increased apoptotic population and intracellular ROS levels. In the proteomic approach 1548 proteins were differentially expressed, out of which 587 exhibited a fold-change ≥ 1.5 and 961 a fold-change ≤ 0.67. Most of these differentially regulated proteins are involved in apoptosis, oxidative stress, glycolytic metabolism, or cytoskeleton structuration. 相似文献