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1.
In this letter, we propose two novel mechanisms which enable GMPLS LMP to cope with the automatic discovery of all-optical transport planes. The feasibility of our contributions and their performances are assessed by simulations as well as experimental results over the ASON/GMPLS CARISMA field-trial  相似文献   
2.
The liquid-phase partial oxidation of propane in the presence of the Fen+/H2O2 Fenton system at 70℃ and 1.4 atm on silica supported Nafion catalysts has been investigated. The reaction proceeds via a radical reaction path the efficiency of which is improved by silica-supported Nafion catalysts. Because of the direct relationship between reaction rate and concentration of sulphonic acid sites of Nafion catalysts, it is inferred that the active phase enahnces the kinetics of propane conversion by promoting the rate of active radicals generation.  相似文献   
3.
通信行业正在迅速从电路交换网络迁移到基于互联网协议(IP)的分组交换网络.IP融合实现了宽带部署、"三网合一"(语音/视频/数据)业务、3G无线和其它通信业务,它们正在为消费者、服务提供商和设备制造商创造令人激动的新机遇.  相似文献   
4.
In this paper two systems, polyethylene (LDPE) and polyethylene/commercial organo-modified montmorillonite (LDPE/OMMT) nanocomposite, were subjected to e-beam irradiation at different doses and both the molecular modifications and mechanical properties have been investigated through solubility, FT-IR, calorimetric and tensile tests. Moreover, in some of the irradiated systems photo-oxidation aging was performed and its effects were studied. The results show an enhancement with irradiation of the positive effect of the nano-filler loading, related to the increase of the mechanical properties, due to the increase of the nano-filler polymer interaction.Nevertheless calorimetric and FT-IR data indicate that the well known reduction of LDPE/OMMT nanocomposite resistance to photo-oxidation ageing, with respect to LDPE, is amplified by ionizing radiation.  相似文献   
5.
Optical channels are currently able to carry 10 Gbit/s and even 40 Gbit/s traffic flows. However, it is not usual to have such amounts of traffic between any pair of client nodes. This article proposes using point-to-multipoint optical channels for the allocation of point-to-point connections in transparent wavelength-routed optical networks. Specifically, when an optical connection between a source-destination node pair has to be established, the optical signal is also sent to some adjacent nodes by introducing passive optical splitters; in this way a light-tree is built. Then, the already established point-to-multipoint optical channel can be used to groom further point-to-point connections between the same source node and each of the other nodes composing the light-tree. The benefits of this strategy are 2-fold: first, the reduction of optical transmission equipments allowing cost savings with respect to the traditional typical point-to-point approach and, second, the optimization of the optical channels utilization meeting in such a way Traffic Engineering objectives. The merits of proposed approach are evaluated by simulation.  相似文献   
6.
A new scheme to alleviate contention in optical burst switching networks is proposed. It consists of preventively reserving resources in a node, to be used if resources are busy on the next hop node. The burst is sent back to the preceding node and then resent forward. Simulations are carried out to assess the feasibility of the proposed scheme. Its performance is compared with that of contention resolution based on deflection routing.  相似文献   
7.
Extensional properties of four high density polyethylenes with different molecular weights and molecular weight distributions are presented. The samples have already been well characterized in shear and non-isothermal extensional flow. The data were collected at 180 °C for elongational rates between 3 · 10–1 and 10–4s–1. Some qualitative and quantitative generalizations of the results are given.  相似文献   
8.
Network survivability requires the provisioning of backup resources in order to protect active traffic against any failure scenario. Backup resources, however, can remain unused most of the time while the network is not in failure condition, inducing high power consumption wastage, if fully powered on. In this paper, we highlight the power consumption wastage of the additional resources for survivability in IP/multi-protocol label switching (MPLS) over dense wavelength division multiplexing multi-layer optical networks. We assume MPLS protection switching as the failure recovery mechanism in the network, a solution interesting for current network operators to ensure fast recovery as well as fine-grained recovery treatment per label switched path. Next, we quantitatively show how elastic optical technologies can effectively reduce such a power consumption by dynamically adjusting the data rate of the transponders to the carried amount of traffic.  相似文献   
9.
10.
We provide new elementary proofs of the following two results: every complex variety is locally the graph of a Dir-minimizing function, first proved by Almgren (Almgren’s big regularity paper, volume 1 of World Scientific Monograph Series in Mathematics, 2000); the gradients of Dir-minimizing functions, in principle square-summable, are p-integrable for some p > 2, proved by De Lellis and Spadaro (Higher integrability and approximation of minimal currents, 2009). In the planar case, we prove that our integrability exponents are optimal.  相似文献   
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