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We investigate the problem of optimizing the shape and location of sensors and actuators for evolution systems driven by distributed parameter systems or partial differential equations (PDE). We consider wave, Schrödinger and heat equations on an arbitrary domain Ω, in any space dimension, and with suitable boundary conditions (if there is a boundary) which can be of Dirichlet, Neumann, mixed or Robin...
Pedestrian dead reckoning plays an important role in indoor pedestrian localization applications. Although this approach has a notable advantage that no extra infrastructure is required, it also suffers an issue known as the drift, which means the estimation errors accumulate and ultimately may make the result unreliable. In this paper, we propose a circular inference method applying online learning...
In cognitive radio networks where secondary users (SUs) access spectral white spaces left by primary users (PUs), there exists a trade-off between sensing and transmission. However, the white spaces depend on the PUs' traffic patterns, and this fact can be utilized to optimize SU transmissions after traffic identification. This paper studies the effective approaches to adapt SU transmissions to the...
In distributed optimization problems, each agent can get information only from a neighborhood defined by a network topology to minimize a global objective function in a networked system. To solve this problem, we present a local strategy based on population dynamics, in order to perform a dynamic resource allocation in a system described by connected graph. The local replicator equation (LRE) is applied...
This paper presents a method of determining optimal contact transition times for a surface exploration task. A transition time optimization algorithm is developed which uses a measure of ergodicity as the objective function, requiring the time-averaged dynamics of the system to optimally approximate the spatial average of a distribution on a finite time interval. This approach is demonstrated to be...
A multichannel characterization for autoregressive moving average(ARMA) spectrum estimation in subbands with applications to cognitive radio spectrum sensing is considered in this presentation. The fullband ARMA spectrum estimation can be realized in two-channels as a special form of this characterization. A complete orthogonalization of input multichannel data is accomplished using a modified form...
In this paper, we consider resource allocation for downlink OFDMA-based cognitive radio (CR) networks. Instead of using only channel information, the statistics of the sensing information conditioned on the primary user (PU) activity is also incorporated in the design and the optimization of the resource allocation. The objective is to maximize the ergodic weighted sum-rate under total power constraint...
We provide an optimal strategy for an autonomous vehicle to detect a target in a mine hunting operation or in a search & rescue mission. We assume that the target exhibits mirror symmetry. By mirror symmetry, we mean that the left hand side of a target is the mirror image of the right hand side of the same target, and the probability of detection is maximal when a target is viewed at zero degree...
Partial shading of a photovoltaic array is the condition under which different parts of the array experience different irradiance levels due to shading. The difference in irradiance levels causes mismatch between the modules of the photovoltaic array, leading to undesirable effects such as reduction in generated power from the modules of the array and hot spots inside the array. The severity of these...
In the context of primary/secondary spectrum sharing, we propose a randomized secondary access strategy with access probabilities that are a function of both the primary automatic repeat request (ARQ) feedback and the spectrum sensing outcome. The primary terminal operates in a time slotted fashion and is active only when it has a packet to send. The primary receiver can send a positive acknowledgment...
Voronoi coverage control is the problem of locating vehicles at the centroid of their Voronoi cell. This problem is often used to model the task of deploying sensors to cover a planar area. Until recently, extensions to cover non-convex regions assumed visibility was never blocked. Nevertheless, visibility is an important consideration when deploying some types of sensors. This paper focuses on the...
This work offers a framework for predicting the delays of individual design paths at the post-silicon stage which is applicable to post-silicon validation and delay characterization. The prediction challenge is mainly due to limited access for direct delay measurement on the design paths after fabrication, combined with the high degree of variability in the process and environmental factors. Our framework...
Two objectives of sensing in cognitive radio (CR) are to detect the primary user (PU) accurately and quickly, which are contradicting objectives. Therefore, many papers try to optimize this tradeoff and find the minimum sensing time which protects the PU. The trends are classified in enhancing false alarm probability (Pf) and detection probability (Pd), optimizing inter-sensing time, in-band sensing...
In this paper we present an approach to solving a stochastic multi-target interception problem. In the multi-target interception problem, a team of mobile sensors is tasked with intercepting a set of potential targets to reduce appropriately assigned damage cost. Our principal contribution is to express a stochastic version of the problem with a generalized cost as a mixed-integer linear program so...
This paper presents a method for optimal sensor placement for flexible shell structures. The optimization objectives are the number of sensors, as a surrogate for implementation cost, and an observability measure. The latter is derived from the observability gramian and considers observation energy of the least observable state. The methodology is tested on a flexible thin-shell structure that is...
Cyber-physical systems (CPS) represent the information technology quest of the 21-st century for a better, cleaner, safer life by integrating computation, communication, and control with physical processes. Physical processes are ubiquitously non-stationary and require time-dependent models for modeling and understanding their behavior. In contrast, most current computing platforms and their design...
Given a number of patrollers, the channel patrol problem consists of determining the periodic trajectories that the patrollers must trace out so as to maximize the probability of detection of the intruder. We formulate this problem as an optimal control problem. We assume that the patrollers' sensors are imperfect and that their motions are subject to turnrate constraints, and that the intruder travels...
Redundant node deployment has an impact on network lifetime because redundant nodes consume excess energy by performing unnecessary repetitious tasks. A distributed node redundancy identification method, called Self-Calculated Redundancy Check (SCRC), is proposed to eliminate redundant tasks. A grid is assumed over the field to help each node to calculate its own redundancy by checking the coverage...
This work is motivated by the U.S. Air Forces Intelligence, Surveillance and Reconnaissance (ISR) mission, where an Unmanned Aerial Vehicle (UAV), or an agent, is to fly over a number of unidentified objects within a given search area, collect information using onboard sensors, and classify the objects. The problem is challenging because the mission time is limited, the agent is only provided with...
We investigate buried depleted uranium detection and classification using data collected with short sensor dwell time (i.e., less than or equal to 1s). Under this circumstance, the gamma spectroscope collected by a NaI detector can be sparse and random, and may be severely affected by energy counts from the background. Several spectral transformations using binned energy windows can help alleviate...
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