Biblio

High-temperature magnetic properties of the anisotropic bulk SmCo7/Fe(Co) nanocomposite magnets prepared by multistep deformation have been investigated and compared with the corresponding isotropic nanocomposites. The anisotropic SmCo7/Fe(Co) nanocomposites with a Fe(Co) fraction of 28% exhibit much higher energy products than the corresponding isotropic nanocomposites at both room and high temperatures. These magnets show a small remanence (α = -0.022%/K) and a coercivity (β = -0.25%/K) temperature coefficient which can be comparable to those of the conventional SmCo5 and Sm2Co17 high-temperature magnets. The magnetic properties of these nanocomposites at high temperatures are sensitive to the weight fractions of the Fe(Co) phase. This paper demonstrates that the anisotropic bulk SmCo7/Fe(Co) nanocomposites have better high-temperature magnetic properties than the corresponding isotropic ones.

Tactical MANETs are deployed in several challenging situations such as node mobility, presence of radio interference together with malicious jamming attacks, and execrable terrain features etc. Jamming attacks are especially harmful to the reliability of wireless communication, as they can effectively disrupt communication between any node pairs. The nature of Tactical MANETs hinders ineffective most of existing reliable routing schemes for ordinary wireless mobile networks. Routing Protocols in Tactical MANET s face serious security and reliability challenges. Selecting a long lasting and steady-going route is a critical task. Due to the lack of accurate acquisition and evaluation of the transmission characteristics, routing algorithms may result in continual reconstruction and high control overhead. This paper studies the impact of jamming and interference on the common protocols of tactical communications and presents a neighbor dependency-based reliable routing algorithm. According to the neighbor dependency based on channel state information evaluated by Exponential Smoothing Method, how to select a neighboring node as the next hop will greatly affect the transmission reliability. Finally, the performance of the reliable routing protocol based on neighbor dependency is tested in OPNET, and compared with the classical AODV algorithm and the improved AODV based on link Cost (CAODV) algorithm. The simulation results show that the protocol presented in this paper has better data transmission reliability.