15224667
Remaining Delivery Time Estimation Based Routing for Intermittently Connected Mobile Networks
We propose Remaining Delivery Time Estimation based Routing (RDTER), a single-copy routing protocol for intermittently connected mobile networks. Nodes predict the Remaining Delivery Time (RDT) to each destination based on the distance estimations obtained from the recent two consecutive contact records. The distance estimation is set to be proportional to the inter-node encounter age, which is updated with transitivity upon each contact. Packet is forwarded to the encountered node whose RDT estimation to the destination is smaller. RDTER provides better forwarding direction, because a smaller RDT estimation means a node is more likely to meet the destination sooner. Thus the routing performance, especially the average delay could be improved. Simulations show that RDTER performs well under the random waypoint mobility model.
26646151
Research on Radar Targets Recognition by Extracting 3-D Characteristic from ISAR Images
Based on ISAR imaging technology and Computer Vision theory, a novel target recognition method extracting the 3-Dimensional characteristic of targets from ISAR images sequence is presented in this paper, which can get higher recognition rate with fewer samples.
10172928
Texture-Consistent Shadow Removal
This paper presents an approach to shadow removal that preserves texture consistency between the original shadow and lit area. Illumination reduction in the shadow area not only darkens that area, but also changes the texture characteristics there. We achieve texture-consistent shadow removal by constructing a shadow-free and texture-consistent gradient field. First, we estimate an illumination change surface which causes the shadow and remove the gradients it induces. We approximate the illumination change surface with illumination change splines across the shadow boundary. We formulate estimating these splines as an optimization problem which balances the smoothness between the neighboring splines and their fitness to the image data. Second, we sample the shadow effect on the texture characteristics in the umbra and lit area near the shadow boundary, and remove it by transforming the gradients inside the shadow area to be compatible with the lit area. Experiments on photos from Flickr demonstrate the effectiveness of our method.
1036059
Neighbor Relationship and Optimization in Mesh Overlay Multicast
Nodes in mesh overlay multicast system don't have fixed parent-children relationship like that in trees and form neighbors. But in data-driven mesh and based on pulling method, for each packet, it still follows a certain tree and the parent-children relationship does exist. While having the powerful peers stay closer to the source may improve the performance, we make the peers of high out bandwidth preempt the neighbor of the peers near the source. In our paper, we describe the delivery trees set and construct the main distribution tree, which carries most of the data, to construct the signaling path and relay priority preemption message to reduce the cost. We model the neighbor relationship to decide which neighbor to be preempted based on the capacity of the node and the contribution it makes to the probed nodes. Our simulations show that after a temporary reduction in performance at the beginning, which for the optimization chaos of optimization procedure, the system converges to a stable state and gains better performance, especially for playback delay, and meanwhile the control overhead is in reasonable range.
17180210
An efficient distributed algorithm for constructing delay- and degree-bounded application-level multicast tree
In this paper we investigate the problem of finding a delay- and degree-bounded maximum sum of nodes application level multicast tree. We then proved the problem is NP-hard, and its relationship with the well-studied degree-bounded minimum maximum-delay multicast tree problem. We propose a distributed algorithm - OverStream, which adopts PPAF heuristic for father node to choose optimal child nodes based on multiple network parameters. Simulation results show that our algorithm is better than OMNI, SpreadIt, HMTP, and Zigzag in general.
6688376
Frequency sensitivity in Hodgkin–Huxley systems
Abstract. The frequency sensitivity of weak periodic signal detection has been studied via numerical simulations for both a single neuron and a neuronal network. The dependence of the critical amplitude of the signal upon its frequency and a resonance between the intrinsic oscillations of a neuron and the signal could account for the frequency sensitivity. In the presence of both a subthreshold periodic signal and noise, the signal-to-noise ratio (SNR) of the output of either a single neuron or a neuronal network present the typical characteristics of stochastic resonance. In particular, there exists a frequency-sensitive range of 30–100 Hz, and for signals with frequencies within this range the SNRs have large values. This implies that the system under consideration (a single neuron or a neuronal network) is more sensitive to the detection of periodic signals, and the frequency sensitivity may be of a functional significance to signal processing.
16207810
Web Services Methods for Communication over IP
In this paper, we study Web services methods and approaches to enable real-time communication services over IP. This approach extends Web services methodologies from service integration to a service-oriented approach for communication. In particular, we describe the generic Web service based application session management, WS-Session, the two-way full duplex Web service interaction framework, and most importantly, the development of Web service initiation protocol (WIP) which is a full featured Web service and SOA based communication framework for multimedia and voice communication over IP. We show that WIP provides a service oriented architecture which can be extended seamlessly from a P2P endpoint to an endpoint with advanced call control and switching capabilities typically requiring the assistance of a dedicated PBX. A prototype of WIP system is fully developed. Architectural design and system implementation of Web service based communication endpoints are studied and applied to realize service-oriented communication over IP. Advances of WIP indicate the beginning of a full Web service and SOA based communication paradigm that can reshape the converged communication over IP.