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排序方式: 共有863条查询结果,搜索用时 15 毫秒
31.
Liu K.H. Changdong Liu Pastor J.L. Roy A. Wei J.Y. 《Communications, IEEE Transactions on》2002,50(10):1662-1679
With the widespread deployment of Internet protocol/wavelength division multiplexing (IP/WDM) networks, it becomes necessary to develop traffic engineering (TE) solutions that can effectively exploit WDM reconfigurability. More importantly, experimental work on reconfiguring lightpath topology over testbed IP/WDM networks is needed urgently to push the technology forward to operational networks. This paper presents a performance and testbed study of topology reconfiguration for IP/WDM networks. IP/WDM TE can be fulfilled in two fashions, overlay vs. integrated, which drives the network control software, e.g., routing and signaling protocols, and selects the corresponding network architecture model, e.g., overlay or peer-to-peer. We present a traffic management framework for IP over reconfigurable WDM networks. Three "one-hop traffic maximization"-oriented heuristic algorithms for lightpath topology design are introduced. A reconfiguration migration algorithm to minimize network impact is presented. To verify the performance of the topology design algorithms, we have conducted extensive simulation study. The simulation results show that the topologies designed by the reconfiguration algorithms outperform the fixed topology with throughput gain as well as average hop-distance reduction. We describe the testbed network and software architecture developed in the Defense Advanced Research Projects Agency (DARPA) Next Generation Internet (NGI) SuperNet Network Control and Management project and report the TE experiments conducted over the testbed. 相似文献
32.
2)香波洗涤条件
按照泡沫均质搅拌测试的要求备好香波样品,将样品加热至40℃后放入颗粒图像测量仪的玻璃贮液器。启动测量仪成像系统后,将发束放入配方液,浸泡约30s,随后清洗30s,风干。 相似文献
33.
Pablo Toharia Oscar D. Robles Ricardo Suárez Jose Luis Bosque Luis Pastor 《Journal of Parallel and Distributed Computing》2012
This paper presents an analysis of a Multi-GPU Multi-CPU environment, along with the different possible hybrid combinations. The analysis has been performed for a shot boundary detection application, based on Zernike moments, although it is general enough to be applied to many different application areas. A deep study of the performance, bottlenecks and design challenges is carried out showing the validity of this approach and achieving very high frame per second rates. In this paper, Zernike calculations are carried out on GPUs, taking advantage of a packing strategy proposed to minimize host-device communication time. 相似文献
34.
Alexander Herzog Peter Pastor Mrinal Kalakrishnan Ludovic Righetti Jeannette Bohg Tamim Asfour Stefan Schaal 《Autonomous Robots》2014,36(1-2):51-65
The ability to grasp unknown objects still remains an unsolved problem in the robotics community. One of the challenges is to choose an appropriate grasp configuration, i.e., the 6D pose of the hand relative to the object and its finger configuration. In this paper, we introduce an algorithm that is based on the assumption that similarly shaped objects can be grasped in a similar way. It is able to synthesize good grasp poses for unknown objects by finding the best matching object shape templates associated with previously demonstrated grasps. The grasp selection algorithm is able to improve over time by using the information of previous grasp attempts to adapt the ranking of the templates to new situations. We tested our approach on two different platforms, the Willow Garage PR2 and the Barrett WAM robot, which have very different hand kinematics. Furthermore, we compared our algorithm with other grasp planners and demonstrated its superior performance. The results presented in this paper show that the algorithm is able to find good grasp configurations for a large set of unknown objects from a relatively small set of demonstrations, and does improve its performance over time. 相似文献
35.
Elena Pastor‐Cavada Silvina R. Drago Rolando J. González Rocío Juan Julio E. Pastor Manuel Alaiz Javier Vioque 《International Journal of Food Science & Technology》2013,48(9):1949-1955
Flour blends based on whole corn and rice with two added wild legumes at 15% level of cereal replacement were extruded to produce whole grain snacks. Extrusion temperature was 175 °C, and the moisture content was adjusted to 14%. The extruded products were evaluated for their physical, chemical and nutritional properties. Results showed that the addition of legumes produces a decrease in expansion in rice‐containing samples and an increase in solubility in corn‐containing samples. With only 15% of legume added to cereal, a significant increase in protein content and quality was obtained. An increase in fibre, polyphenol, iron and zinc content was also obtained. Protein digestibility was in the range of 81.8–85.3%. Mineral availability ranged from 6.4 to 16.3% for iron and 10–16.3% for zinc. The performance of each mixture during extrusion and the physical properties of the extruded products were considered to be similar to those expected for snack‐type products and described in the literature. 相似文献
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39.
Rita B. Figueira Carlos J. R. Silva Elsa V. Pereira 《Journal of Coatings Technology and Research》2016,13(2):355-373
The aim of this experimental research was to study the electrochemical behavior of organic–inorganic hybrid (OIH) coatings for corrosion protection of hot-dip galvanized steel (HDGS) in the first instants of immersion in simulated concrete pore solution (SCPS) (pH > 12.5). The electrochemical performance of the OIH coatings was assessed by electrochemical impedance spectroscopy, potentiodynamic polarization curves, macrocell current density, and polarization resistance. The OIH coatings were prepared via the sol–gel method and were deposited on HDGS surfaces by dip-coating using one or three dip steps. The electrochemical results obtained for HDGS samples coated with OIH matrices in SCPS showed higher corrosion resistance than bare HDGS; as the molecular weight (MW) of Jeffamine® increased the barrier protection of the coating decreased. The lowest protection efficiency was found for HDGS samples synthesized with oligopolymers with an MW of 2000. Coatings produced with an oligopolymer of 230 MW conferred the highest protection. The surface morphology of the OIH coatings deposited on HDGS surfaces was studied by atomic force microscopy. The results show that the roughness of the OIH films depends on the MW of Jeffamine® and on the number of dip-coating steps used. Thermogravimetry results show that the Jeffamine® MW affected the thermal properties of the prepared OIH samples. The prepared OIH materials are thermally stable within the range of 20–80°C. 相似文献
40.
Leon Cohen Elsa Sanchez Mariluz Martin Fernando Soto Francisco Trujillo 《Journal of surfactants and detergents》2016,19(5):1089-1092
The effects of both linear alkylbenzene sulfonate (LAS) and zein protein concentrations on protein solubilization were investigated to better understand the influence of increasing concentration of the surfactant on protein denaturation and skin irritation. Different methods have been used for the determination of the amount of protein dissolved. A wide range of LAS concentrations and zein amounts were used. The results confirm that protein solubilization increases with LAS concentration increase and demonstrate that a minimum LAS/Zein ratio exists for all the zein to be dissolved. 相似文献