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71.
Lennard F. Torres Zach McCaffrey Wisdom Washington Tina G. Williams Delilah F. Wood William J. Orts Colleen M. McMahan 《应用聚合物科学杂志》2021,138(28):50684
This study explored the feasibility of using torrefied biomass as a reinforcing filler in natural rubber compounds. Carbon black was then replaced with the torrefied biomass in elastomer formulations for concentrations varying from 0% to 100% (60 parts per hundred rubber or phr total). Their influence on the curing process, dynamic properties, and mechanical properties was investigated. Results were compared with the properties of vulcanizates containing solely carbon black fillers. Time to cure (t90) for compounds with torrefied biomass fillers increased, while filler-filler interactions (ΔG') decreased, compared to carbon black controls. At low strains, the tan δ values of the torrefied fillers vulcanizates were similar to the controls. Incorporation of torrefied biomass into natural rubber decreased compound tensile strength and modulus but increased elongation. Replacement with torrefied fillers resulted in a weaker filler network in the matrix. Still, results showed that moderate substitution concentrations (~20 phr) could be feasible for some natural rubber applications. 相似文献
72.
R. Etchart-Salas V. Rat J. F. Coudert P. Fauchais N. Caron K. Wittman S. Alexandre 《Journal of Thermal Spray Technology》2007,16(5-6):857-865
Direct current Suspension Plasma Spraying (SPS) allows depositing finely structured coatings. This article presents an analysis
of the influence of plasma instabilities on the yttria-stabilized suspension drops fragmentation. A particular attention is
paid to the treatment of suspension jet or drops according to the importance of voltage fluctuations (linked to those of the
arc root) and depending on the different spray parameters such as the plasma forming gas mixture composition and mass flow
rate and the suspension momentum. By observing the suspension drops injection with a fast shutter camera and a laser flash
sheet triggered by a defined transient voltage level of the plasma torch, the influence of plasma fluctuations on jet or drops
fragmentation is studied through the deviation and dispersion trajectories of droplets within the plasma jet.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
73.
74.
Alexandre Sawczuk da Silva Hui Ma Mengjie Zhang 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2016,20(10):3851-3867
Web services, which can be described as functionality modules invoked over a network as part of a larger application are often used in software development. Instead of occasionally incorporating some of these services in an application, they can be thought of as fundamental building blocks that are combined in a process known as Web service composition. Manually creating compositions from a large number of candidate services is very time consuming, and developing techniques for achieving this objective in an automated manner becomes an active research field. One promising group of techniques encompasses evolutionary computing, which can effectively tackle the large search spaces characteristic of the composition problem. Therefore, this paper proposes the use of genetic programming for Web service composition, investigating three variations to ensure the creation of functionally correct solutions that are also optimised according to their quality of service. A variety of comparisons are carried out between these variations and two particle swarm optimisation approaches, with results showing that there is likely a trade-off between execution time and the quality of solutions when employing genetic programming and particle swarm optimisation. Even though genetic programming has a higher execution time for most datasets, the results indicate that it scales better than particle swarm optimisation. 相似文献
75.
76.
Nicolas?PécheuxEmail author Alexandre?Allauzen Jan?Niehues Fran?ois?Yvon 《Language Resources and Evaluation》2016,50(2):375-410
In Statistical Machine Translation (SMT), the constraints on word reorderings have a great impact on the set of potential translations that is explored during search. Notwithstanding computational issues, the reordering space of a SMT system needs to be designed with great care: if a larger search space is likely to yield better translations, it may also lead to more decoding errors, because of the added ambiguity and the interaction with the pruning strategy. In this paper, we study the reordering search space, using a state-of-the art translation system, where all reorderings are represented in a permutation lattice prior to decoding. This allows us to directly explore and compare different reordering schemes and oracle settings. We also study in detail a rule-based preordering system, varying the length and number of rules, the tagset used, as well as contrasting with purely combinatorial subsets of permutations. We carry out experiments on three language pairs in both directions: English-French, a close language pair; English-German and English-Czech, two much more challenging pairs. We show that even though it might be desirable to design better reordering spaces, model and search errors seem to be the most important issues. Therefore, improvements of the reordering space should come along with improvements of the associated models to be really effective. 相似文献
77.
Emre Akyurek Alexandre Dilly Fabrice Jourdan Zhu Liu Souraneel Chattoraj Itziar Berruezo Juandeaburre Michel Heinrich Leonid Paramonov Peter Turner Stelarc Tatiana Kalganova 《计算机技术与应用:英文》2013,(11):569-574
In the development of robotic limbs, the side of members is of importance to define the shape of artificial limbs and the range of movements. It is mainly significant tbr biomedical applications concerning patients suffering arms or legs injuries, fn this paper, the concept of an ambidextrous design lbr robot hands is introduced. The fingers can curl in one xvay or another, to imitate either a right hand or a left hand. The advantages and inconveniences of different models have been investigated to optimise the range and the maximum force applied by fingers. Besides, a remote control interthce is integrated to the system, allowing both to send comrnands through internet and to display a video streaming of the ambidextrous hand as feedback. Therefore, a robotic prosthesis could be used for the first time in telerehabilitation. The main application areas targeted are physiotherapy alter strokes or management of phantom pains/br amputees by/earning to control the ambidextrous hand. A client application is also accessible on Facehook social network, making the robotic limb easily reachable for the patients. Additionally the ambidextrous hand can be used tbr robotics research as well as artistic performances. 相似文献
78.
Lu??s Antunes Armando Matos Alexandre Pinto Andr?? Souto Andreia Teixeira 《Theory of Computing Systems》2013,52(1):162-178
We prove several results relating injective one-way functions, time-bounded conditional Kolmogorov complexity, and time-bounded conditional entropy. First we establish a connection between injective, strong and weak one-way functions and the expected value of the polynomial time-bounded Kolmogorov complexity, denoted here by?E(K t (x|f(x))). These results are in both directions. More precisely, conditions on?E(K t (x|f(x))) that imply that?f is a weak one-way function, and properties of?E(K t (x|f(x))) that are implied by the fact that?f is a strong one-way function. In particular, we prove a separation result: based on the concept of time-bounded Kolmogorov complexity, we find an interval in which every function?f is a necessarily weak but not a strong one-way function. Then we propose an individual approach to injective one-way functions based on Kolmogorov complexity, defining Kolmogorov one-way functions and prove some relationships between the new proposal and the classical definition of one-way functions, showing that a Kolmogorov one-way function is also a deterministic one-way function. A relationship between Kolmogorov one-way functions and the conjecture of polynomial time symmetry of information is also proved. Finally, we relate?E(K t (x|f(x))) and two forms of time-bounded entropy, the unpredictable entropy?H unp, in which ??one-wayness?? of a function can be easily expressed, and the Yao+ entropy, a measure based on compression/decompression schema in which only the decompressor is restricted to be time-bounded. 相似文献
79.
Santos J.M. de Sa J.M. Alexandre L.A. 《IEEE transactions on pattern analysis and machine intelligence》2008,30(1):62-75
Hierarchical clustering is a stepwise clustering method usually based on proximity measures between objects or sets of objects from a given data set. The most common proximity measures are distance measures. The derived proximity matrices can be used to build graphs, which provide the basic structure for some clustering methods. We present here a new proximity matrix based on an entropic measure and also a clustering algorithm (LEGCIust) that builds layers of subgraphs based on this matrix and uses them and a hierarchical agglomerative clustering technique to form the clusters. Our approach capitalizes on both a graph structure and a hierarchical construction. Moreover, by using entropy as a proximity measure, we are able, with no assumption about the cluster shapes, to capture the local structure of the data, forcing the clustering method to reflect this structure. We present several experiments on artificial and real data sets that provide evidence on the superior performance of this new algorithm when compared with competing ones. 相似文献
80.
Jorge M Santos Joaquim Marques de Sa Luis A Alexandre 《IEEE transactions on pattern analysis and machine intelligence》2008,30(1):62-75
Hierarchical clustering is a stepwise clustering method usually based on proximity measures between objects or sets of objects from a given data set. The most common proximity measures are distance measures. The derived proximity matrices can be used to build graphs, which provide the basic structure for some clustering methods. We present here a new proximity matrix based on an entropic measure and also a clustering algorithm (LEGClust) that builds layers of subgraphs based on this matrix, and uses them and a hierarchical agglomerative clustering technique to form the clusters. Our approach capitalizes on both a graph structure and a hierarchical construction. Moreover, by using entropy as a proximity measure we are able, with no assumption about the cluster shapes, to capture the local structure of the data, forcing the clustering method to reflect this structure. We present several experiments on artificial and real data sets that provide evidence on the superior performance of this new algorithm when compared with competing ones. 相似文献