An intelligent swarm-based guidance and path planning algorithm for the Unmanned Arial Vehicles (UAV) provides
the ability to efficiently carry out grid surveillance, taking into account specific UAV constraints such as maximum
speed, maximum flight time and battery re-charging intervals to allow for continuous surveillance. The swarm-based
flight planning is based on enhancements of distributed computing concepts that have been developed for NASA's
launch danger zone protection. The algorithm is a modified version of an ant colony optimization theory describing ant
food foraging. Ants initially follow random paths from the nest, but if food is found, the ant deposits a pheromone
(modifying the local environment), which influences other ants to travel the same path. Once the food source is
exhausted, the pheromone decays naturally, which causes the trail to disappear. When an ant is on an established trail, it
may at any time decide to follow a new random path, allowing for new exploration. Using these concepts, in our system
for UAV, we use two units, the Rendezvous unit and the Patrol unit. The Rendezvous units will act as pheromone
deposit sites keeping a record of trails of interest (extra pheromone that decays over time), and obstacles (no
pheromone). The search area is divided into a grid of areas. Each area unit is assigned a pheromone weight. The patrol
unit picks an area unit based on a probabilistic formula consisting of parameters like the relative weight of trail
intensity, area visibility to the unit, the distance of the patrol unit from the area, and the pheromone decay factor.
Simulation of a UAV surveillance system based on the above algorithm showed that it has the ability to perform
independently and reliably without human intervention, and the emergent nature of the algorithm has the ability to
incorporate important aspects of unmanned surveillance.
A multi-sensor detection and fusion technology is described in this paper. The system consists of inputs from three
sensors, Infra Red, Doppler Motion, and Stereo Video. The technique consists of three processing parts corresponding
to each sensor data, and a fusion module, which makes the final decision based on the inputs from the three parts. The
signal processing and detection algorithms process the inputs from each sensor and provides specific information to the
fusion module. The fusion module is based on the bayes belief propagation theory. It takes the processed inputs from all
of the sensor modules and provides a final decision for the presence and absence of objects, as well as their reliability
based on the iterative belief propagation algorithm operating on decision graphs. This choice of sensors is designed to
give high reliability. The infra red and Doppler provide detection ability at night, while stereo video has the ability to
analyze depth and range information. The combination of these sensors has the ability to provide a high probability of
detection and a very low false alarm rate. A prototype system was built using this technique to study the feasibility of
intrusion detection for NASA's launch danger zone protection. The system verified the potential of the proposed
algorithms and proved the feasibility of high probability of detection and low false alarm rates compared to many
The use of Internet Protocol (IP) suite over satellite and space platforms is limited by the large propagation delays to
reach their earth-distant position and the wireless nature of channel errors. Before they can provide an effective and
commerciable service, IP protocols require proper augmentation and correction precisely due to long feedback loops,
large number of in-transit packets, transmission errors, possibly asymmetric links and intermittent connectivity. By a
careful collective look to current research literature, we identify that all IP problems in long delay wireless networks
either stem from network measurement inefficiency or can be better overcome if accurate measurements were available.
In this paper, we introduce a flexible middle-box IP performance enhancement solution that deals with the satellite
WAN optimization problem without changes to senders and receivers. It accomplished an IP steady state improvement
factor that corresponds to approximately optimal channel utilization by effectively changing TCP/IP parameters
according to innovative, accurate passive network measurements, suitable for the high bandwidth and delay wireless
environment. We believe that our approach can optimize not only protocols but also improve currently proposed
optimizations as those suggested in the SCPS transport. While this study is focusing on TCP, our concept can take on a
wide number of transport, security, multimedia, real-time and QoS performance enhancements tasks.
Optical or gigabit communication links could currently allow petabytes of data to be transferred to geographically distributed tera-scale computing facilities at beyond 10Gbps rates. While the bandwidth is available in network link technology, transport protocols like TCP/IP and common network host architectures severely limit the attainable throughput over such links. Traditional layering -that is implemented through excessive per-byte (word) memory bandwidth constrained buffer copying- transport processing complexity, combined error and congestion control and trial and error timeout-based approaches result in prohibitively increasing performance degradation as network speeds increase. In this paper we present TCP-Fiber, a TCP version that is based on direct measurements of available and bottleneck link bandwidth and is able to perform decoupled error and congestion control while supporting zero-copy from application to network interface. A key innovation in TCP-Fiber is a variable length "packet train" based method that allows sensing ultra high bandwidth related quantities in a network independent fashion with relaxed requirements to timers and system resources (as related to interrupts, system calls etc). A TCP-Fiber connection is able to fairly send at the full network rate without extensive trial-and-error convergence procedures or waiting on time-out for unacknowledged packets, while maintaining network stability.
In this paper, we propose a novel acoustic sensor network system that can provide road edge detection in order to prevent
rollovers. The system can work in "non-cooperative" road scenarios that do not possess any characteristic "cooperative markings," such as white lines, or pavement at the sidewalk.
A new approach to neural networks is proposed, based on wireless interconnects (synapses) and cellular neurons, both software and hardware; with the capacity of 10<sup>10</sup> neurons, almost fully connected. The core of the system is <i>Spatio-Temporal-Variant</i> (STV) kernel and <i>cellular axon</i> with <i>synaptic plasticity</i> variable in time and space. The novel large neural network hardware is based on two established wireless technologies: RF-cellular and IR-wireless.
Multimedia transports in wireless, ad-hoc, multi-hop or mobile networks must be capable of obtaining information about the network and adaptively tune sending and encoding parameters to the network response. Obtaining meaningful metrics to guide a stable congestion control mechanism in the transport (i.e. passive, simple, end-to-end and network technology independent) is a complex problem. Equally difficult is obtaining a reliable QoS metrics that agrees with user perception in a client/server or distributed environment. Existing metrics, objective or subjective, are commonly used after or before to test or report on a transmission and require access to both original and transmitted frames. In this paper, we propose that an efficient and successful video delivery and the optimization of overall network QoS requires innovation in a) a direct measurement of available and bottleneck capacity for its congestion control and b) a meaningful subjective QoS metric that is dynamically reported to video sender. Once these are in place, a binomial -stable, fair and TCP friendly- algorithm can be used to determine the sending rate and other packet video parameters. An adaptive mpeg codec can then continually test and fit its parameters and temporal-spatial data-error control balance using the perceived QoS dynamic feedback. We suggest a new measurement based on a packet dispersion technique that is independent of underlying network mechanisms. We then present a binomial control based on direct measurements. We implement a QoS metric that is known to agree with user perception (MPQM) in a client/server, distributed environment by using predetermined table lookups and characterization of video content.
Current state of the art security policy technologies, besides the small scale limitation and largely manual nature of accompanied management methods, are lacking a) in real-timeliness of policy implementation and b) vulnerabilities and inflexibility stemming from the centralized policy decision making; even if, for example, a policy description or access control database is distributed, the actual decision is often a centralized action and forms a system single point of failure. In this paper we are presenting a new fundamental concept that allows implement a security policy by a systematic and efficient key distribution procedure. Specifically, we extend the polynomial Shamir key splitting. According to this, a global key is split into n parts, any k of which can re-construct the original key. In this paper we present a method that instead of having "any k parts" be able to re-construct the original key, the latter can only be reconstructed if keys are combined as any access control policy describes. This leads into an easily deployable key generation procedure that results a single key per entity that "knows" its role in the specific access control policy from which it was derived. The system is considered efficient as it may be used to avoid expensive PKI operations or pairwise key distributions as well as provides superior security due to its distributed nature, the fact that the key is tightly coupled to the policy, and that policy change may be implemented easier and faster.
High energy physics, climate computations, nanoscience, fusion energy, astrophysics and genomics are applications with high processing and network demands. Optical components can be useful for these application as they can provide ultra fast, high input/output processing and network switching parts. In this paper a core concept is presented that may allow the systematic programming of linear optical components for optoelectronic processors, network switching or have general digital functionality. In this paper we are dealing with with a fundamental optical digital design concept. An optical automated logic design process is described, under a linear optics model assumption. We use optimization theory and maximum feasibility set (MAX-FS) inspired heuristics to solve the problem of finding optimal performance weights and optical thresholds for the implementation of a digital/switching function with linear optics. This optical design automation (ODA) may evolve into a rapid prototyping environment for fabless opto-electronics companies to
receive custom programming for opto-electronic circuits from system engineers. Using this process, we have successfully high-level designed an 8-bit function using a single optical stage and a minimal electronic component.