a new approach for propulsion system layout that increases power and enhances the efficiency of submarine propulsion system is proposed.using our method,the efficiency and power of the system enhances without increasing volume and weight. this layout improves the performance compared to the usual layout, which employs double-armature motors in cruise speed where efficiency is more critical. thi...

In this paper, we analyze the problem of acoustic ranging between sensor nodes in an underwater environment. The underwater medium is assumed to be composed of multiple isogradient sound speed profile (SSP) layers where in each layer the sound speed is linearly related to the depth. Furthermore, each sensor node is able to measure its depth and can exchange this information with other nodes. Un...

Abstract Optical Communication is widely used in military and civilian backbone network communication, but due to the limitation of “electronic bottleneck”, ability nodes process information optical layer data transmission capacity seriously mismatched, which directly causes cross connectors nodes. The number ports carried has skyrocketed. In order improve processing speed nodes, this paper stu...

This demonstration shows our versatile heterogeneous sensor networks testbed. This testbed supports high speed embedded WLAN node, medium speed IEEE802.15.4 node, wired computer and so on with powerful supervision platform. The unique features of the testbed are as follows: (1) Supporting heterogeneous sensor networks; (2) Owning powerful testbed nodes; (3) Emulating the interference and noise ...

In a sparse mobile network where delay tolerant network routing helps message dissemination, some temporary or persistent stable concentrations of mobile nodes in time domain can help message disseminations more efficiently. The feature can be created due to movements revealing common goals intentionally or less intentionally. However, a mobile network application can generate complex mixing mo...

Optical interconnection networks have the potential of transmitting data much faster than the speed at which this data can be generated at the transmitting nodes or consumed at the receiving nodes. Even when the communication protocols are simpliied and most of the protocol signaling at the end nodes is done in hardware, the data cannot be processed at the end nodes at a rate faster than the ra...

coeffcient of  friction  (cof)  for  rubber parts  is one of  the key parameters in their interaction with solid rough surfaces (micrometer to millimeter scales),  such  as  tire-road  interactions. cof  of  rubber  depends  on  viscoelastic properties of rubber, roughness characteristics of the counter-part surface, and process variables such as contact nominal pressure and sliding speed. due ...

Underwater wireless sensor networks consist of a certain number of sensors and vehicles that interact to collect data and perform collaborative tasks. The sensor network consists of static and mobile underwater sensor nodes. The nodes communicate point-to-point using a novel high-speed optical communication system integrated into the TinyOS stack or other small operating system, and they broadc...

As users of networks such as the Internet have increased, the amount of traffic has steadily increased. Various applications that utilize images have come to be used, and the demands made on the technology that enables the high speed and large scale transmission in a network have increased. To satisfy these demands, research into optical technologies like IP over a WDM network, GMPLS, and optic...