ATD: Statistical Methods for Nuclear Material Surveillance Using Mobile Sensors

本提案中的研究概述了一个强大的移动传感器网络系统，并开发了统计算法和模型，为主要城市的核或生物材料提供一致、普遍和动态的监测。具体而言，该项目提出了一种新颖的传感器网络设计，在出租车和警车等大量车辆上安装核传感器和全球定位系统（GPS）跟踪设备。来自该网络的实时信息在中央监控中心进行处理，并进行数学和统计分析。提出的统计方法包括基于潜在模型的多空间聚类检测方法和基于序贯蒙特卡罗方法的状态空间模型对可能移动的核源进行实时检测和跟踪。这些方法具有通用性和灵活性，可用于涉及大量传感器网络的其他设置。在过去十年中，由于全球恐怖主义、对美国利益的反对增加以及对手获得尖端技术和材料的机会增加，对国家和国土安全的威胁变得更加动态和复杂。在各种威胁中，核攻击是最具破坏性的行为之一，造成严重的生命损失，并对基础设施造成长期和大规模的破坏。因此，人们越来越担心在人口稠密的大都市地区引爆核材料或脏弹的可能性。为了保护基础设施和人类生命，在美国主要城市部署复杂的核监视和探测系统变得越来越重要。拟议的移动传感器网络监控系统研究可以对提高我们对恐怖主义威胁的探测能力产生广泛的影响，从而改善国土安全。在拟议的项目过程中，将积极参与与研究生和本科生的教育和培训有关的活动，为他们可能在这一领域的职业生涯做准备。

The research in this proposal outlines a robust system of a mobile sensor network and develops statistical algorithms and models to provide consistent, pervasive and dynamic surveillance for nuclear or biological materials in major cities. Specifically, the project proposes a novel design of sensor network, in which nuclear sensors and Global Position System (GPS) tracking devices are installed on a large number of vehicles such as taxicabs and police vehicles. Real time information from this network is processed at a central surveillance center, where mathematical and statistical analyses are performed. The proposed statistical approaches include multiple spatial cluster detection method using latent models and state-space model for real-time detection and tracking of possibly moving nuclear sources using sequential Monte Carlo method. The methods are general and flexible and can be used in other settings involving a massive network of sensors. Threats to national and homeland security have become more dynamic and complex in the past decade due to global terrorism, increased opposition to U.S. interests, and increased access by adversaries to sophisticated technologies and materials. Among the threats, nuclear attacks is one of the most devastating acts, with severe losses of human lives as well as long term and large scale damages to infrastructures. As a result, there have been growing concerns regarding the prospect of detonating nuclear materials or dirty bombs in the populous metropolitan areas. It becomes more and more vital to have sophisticated nuclear surveillance and detection systems deployed in major cities in the U.S. to protect infrastructures and human lives. The proposed research on surveillance systems of a mobile sensor network can have broad impacts in advancing our detection capabilities of terrorist threats hence improving homeland security. During the course of the proposed project, activities related to education and training of graduate and undergraduate students will be actively engaged, in preparation for their possible careers in this area.