The bag-of-visual-words (BOVW) approaches are widely used in human action recognition. Usually, large vocabulary size of the BOVW is more discriminative for inter-class action classification while small one is more robust to noise and thus tolerant to the intra-class invariance. In this pape, we propose a pyramid vocabulary tree to model local spatio-temporal features, which can characterize th...

The security services of authentication and confidentiality are of significant importance to ensure secure communication in any network. The decentralized nature and the broadcast medium of communication of wireless ad hoc networks results in unique challenges in realizing the services of authentication and data confidentiality. In this chapter, We first highlight the issues relating to authent...

Pharmaceuticals are common chemical contaminants in estuaries receiving effluent from wastewater and sewage treatment facilities. The purpose of this research was to examine benthic microalgal (BMA) community responses to sublethal exposures to tylosin, a common and environmentally persistent antibiotic. Bioassays, using concentrations of 0.011-218 μmol tylosin l(-1), were performed on intertid...

This paper proposes a highly efficient cryptographic denial of service attack against 802.11 networks using 802.11i TKIP and CCMP. The attacker captures one frame, then modifies and transmits it twice to disrupt network access for 60 seconds. We analyze, implement and experimentally validate the attack. We also propose a robust solution and recommendations for network administrators.

The diet of Cichla kelberi introduced in an artificial lake in Leme-SP was predominantly composed of common fish species (Oreochromis niloticus and C. kelberi). In the spring and summer, the most consumed item was O. niloticus. However, cannibalism was very common for this species. The high frequencies of O. niloticus and C. kelberi reveal that this species is adapted to a seasonal cycle, feedi...

In a topological structure affected by geographical constraints on liking, the connectivity is weakened by constructing local stubs with small cycles, a something of randomness to bridge them is crucial for the robust network design. In this paper, we numerically investigate the effects of adding shortcuts on the robustness in geographical scale-free network models under a similar degree distri...

Liquid Crystals Publication details, including instructions for authors and subscription information: http://www.informaworld.com/smpp/title~content=t713926090 Non-equilibrium molecular-dynamics measurement of the Leslie coefficients of a Gay-Berne nematic liquid crystal Congmin Wu a; Tiezheng Qian b; Pingwen Zhang a a LMAM, CCSE and School of Mathematical Science, Peking University, Beijing 10...

Supporting user mobility is one of the most challenging issues in wireless networks. Recently, as the desires for the user mobility and high-quality multimedia services increase, fast handoff among base stations comes to a center of quality of connections. Therefore, minimizing re-authentication latency during handoff is crucial for supporting various promising real-time applications such as Vo...

IEEE 802.11 networks are insecure. Wired Equivalent Privacy (WEP), the security mechanism used in 802.11, was proved to be vulnerable. IEEE 802.11i, the security enhancement, concentrates only on integrity and confidentiality of transmitted frames. Either version did not properly handle the network availability. Because management frames are not authenticated, {802.11, 802.11i} networks are sus...