Multi-agent unmanned aerial vehicle (UAV) teaming becomes an essential part in science mission, modern warfare surveillance, and disaster rescuing. This paper proposes a decentralized UAV swarm persistent monitoring strategy realizing continuous sensing coverage network service. A two-layer (high altitude low altitude) hierarchical structure is adopted the accurate object tracking area of inter...

Large RAM caches are generally used to speed up disk accesses. Such caches more eeectively improve read performance than write performance, since write requests must be frequently written into disks to protect them from data loss or damage due to system failures. While Non-volatile RAM (NVRAM) caches can be used to improve write performance, large NVRAM caches are too expensive for many applica...

Two typical architectures of parallel database systems are the shared-everything and shared-nothing architectures. Shared-everything architecture provides better performance than the shared-nothing architecture but it is not scalable to large system sizes. On the other hand, shared-nothing architecture provides good system scalability but is sensitive to data skew. Hierarchical architectures ha...

E ective management of battle eld networks requires a hierarchical network management architecture wherein managers can dynamically delegate management tasks to intermediate managers. In this paper we describe a novel framework called SHAMAN Spreadsheet-based Hierarchical Architecture for MANagement which extends the traditional at SNMP management model to a hierarchical architecture. We descri...

Although the Automatically Switched Optical Networks (ASON) specifications strongly recommend a hierarchical network architecture for these networks, this is still an open issue. The hierarchical network concept involves several mechanisms mainly related with signalling and routing, such as the aggregation scheme, the dissemination process, the updating policy and the routing algorithms. The ex...

this paper presents a modified 32-bit rom-based direct digital frequency synthesizer (ddfs). maximum output frequency of the ddfs is limited by the structure of the accumulator used in the ddfs architecture. the hierarchical pipeline accumulator (hpa) presented in this paper has less propagation delay time rather than the conventional structures. therefore, it results in both higher maximum ope...

This paper describes a hierarchical scheduling, planning, control, and execution monitoring architecture for automating operations of a worldwide network of communications antennas. We describe the network automation problem and current mode of operations. We then describe a three layer hierarchical architecture for automating network operations. In particular we describe the notion of plan/sch...