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2 nanofibers and nanotubes were synthesized by electrospinning method. Magnetization measurement indicates that the 2 nanofibers and nanotubes annealed in air at 500°C exhibit the room-temperature ferromagnetism and the ferromagnetism of nanotubes is stronger than the nanofibers. Selected area electron diffraction, X-ray diffraction and Raman measurements show that all the samples possess a typical rutile structure and no other impurity phases are observed. The results of the Raman spectra also indicate that there are lots of defects existing in the fabricated samples. The observed room-temperature ferromagnetism in 2 nanofibers and nanotubes possibly originates from oxygen vacancies. The field cooled (FC) and zero-field-cooled (ZFC) magnetization curves indicate that the Curie temperature TC is above 300 K. SnO2 nanofibers and nanotubes were synthesized the electrospinning method. The observed room-temperature ferromagnetism originates from surface defects. [ABSTRACT FROM AUTHOR]

Service selection is a key step to transform a user's request into an optimal composite service plan. Most existing approaches are influenced by the number of tasks and candidate services and have shortcomings of long response time for large size candidate services and without considering the critical path. To solve above problems, a peer-to-peer (p2p) service overlay was built up to simulate distributed applications. Considering the composite construction and critical path, the end-to-end QoS constraint could be decomposed into local ones by using the management of service community, which facilitates parallel service selection. Experimental results demonstrate that the composite service plan could be built up with great reduced response time and the tradeoff to a near-optimal result. [ABSTRACT FROM AUTHOR]

To guarantee the rationality of the resource access and the correctness of the protocol design, an access control protocol is proposed and the designed protocol is modeled in Petri-net. Firstly, the protocol is analyzed by means of the properties of Petri-net to prove its correctness. Then, the protocol model is created, run and debugged using CPN Tools. The performance is simulated by means of observing the running steps of the protocol. The experiment results show that stepping into the protocol is very helpful to discover or eliminate the designing bug and to optimize the protocol design for meeting the given goal. [ABSTRACT FROM AUTHOR]

In order to implement Web service selection effectively, a service selection model based on multi-agent collaboration is constructed. Communication performatives in multi agent system for service selection are designed, by which agents perform collaboration. The evaluation algorithm based on fuzzy matching is proposed, which provide consistent measure for evaluation criteria. The preferences of service requestors are aggregated according to the voting protocol, by which the right value of each evaluation item it taken. Experimental results demonstrate that the mean effectiveness of service selection is increased by 29 percent; the average selection time decreased by 58 percent, and the computing complexity drops from O(n5) to O(n²) in the model. [ABSTRACT FROM AUTHOR]

Inorder to improve the execution performance of Web Service Composition, the concept of Web service composition net system based on Colored Petri net is proposed to model and analyze the execution of Web service composition. In the use case of electronic resource cross-liberary searching system, the network delay, data dependence and control dependence between nodes were included in the expected models and the buffer-restricted models. By means of the CPN tools, a powerful simulation platform, the correctness of the above models was verified, and the query delay, successful query ratio, the buffer occupancy rate were mornitored. Simulation result showed that the distributed model was more efficient than the central model no matter it worked under buffer-restricted policy or not. [ABSTRACT FROM AUTHOR]

In order to reduce network load, energy consumption and delay in video sensor network, a layered multi-quality image fusion method based on attention is proposed. A dynamic attention based wakeup mechanism is established by structured deployment and region-mapping between views of nodes. The low-quality image acquired by high-layer node is fused with high-quality images from low-layer node, and the attention target is enhanced. Experiment results further showed that the fusion method is effective. [ABSTRACT FROM AUTHOR]

A Web service discovery method (I-Wander) based on unstructured P2P network is proposed. The Web services with same functional properties are clustered into a community. While the query packets wandered among these communities, the current community and node are recorded into a known list. The known list is updated in each hop and exchanged when two packets bumped. A query packet is proliferated through the community which most matches against the query. According to the non-functional properties, the best service is elected out for Web service integration. The results of experiments showed that service clustering and experience exchanging cut down the probing cost and enhanced the efficiency of Web service discovery. [ABSTRACT FROM AUTHOR]

Aiming at a simplified and static hoist system in the vertical direction, the equations of motion for a rope and hoist object attached at the lower end of the rope were established. By means of the variables substitution, it is found that the equation of motion for the rope is just a Mathieu equation. Based on the theory about Mathieu equation, the reasons that cause the rope to vibrate laterally with constant, decaying and emanative amplitude were analyzed. Some simulation and experiment were performed to verify the theoretical results. Consequently, the foundation to solve the problem of the large-amplitude lateral vibration of the rope in a running vertical hoist system was established. [ABSTRACT FROM AUTHOR]

The genus-level recognition of monophyletic short-legged toads ( Brachytarsophrys ) has been recently implicated in the taxonomic debate of Megophrys sensu lato . In the present study, Brachytarsophrys is reasonably regarded as a distinct genus based on significant morphological differentiations and recent molecular analyses. Furthermore, a comprehensive review of this genus is performed, with two species groups proposed based on morphological differences and phylogenetic relationships. Particularly, Brachytarsophrys platyparietus is removed as a synonym of Brachytarsophrys carinense and considered a valid species due to significant genetic divergence and distinct morphological differences. In addition, a new species, Brachytarsophrys orientalis sp . nov ., is described based on a series of specimens collected from southeastern China. This work takes the member species of the genus Brachytarsophrys to seven, suggesting that the diversity of Brachytarsophrys is underestimated. In addition, the genus levels of other monophyletic groups within the subfamily Megophryinae are discussed.