In this paper we introduce CARRQR, a communication avoiding rank revealing QR factorization with tournament pivoting. We show that CARRQR reveals the numerical rank of a matrix in an analogous way to QR factorization with column pivoting (QRCP). Although the upper bound of a quantity involved in the characterization of a rank revealing factorization is worse for CARRQR than for QRCP, our numerical experiments on a set of challenging matrices show that this upper bound is very pessimistic, and CARRQR is an effective tool in revealing the rank in practical problems. Our main motivation for introducing CARRQR is that it minimizes data transfer, modulo poly- logarithmic factors, on both sequential and parallel machines, while previous factorizations as QRCP are communication sub-optimal and require asymptotically more communication than CARRQR. Hence CARRQR is expected to have a better performance on current and future computers, where communication is a major bottleneck that highly impacts the performance of an algorithm.

关键词：通信；列主元QR分解；减少通信；矩阵秩

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The goal of this project relates to e ective management of emergencies or disasters that impact large urban structures, such as commercial buildings, arenas or stadiums and their surrounding street networks. The project has resulted in the E ective Emergency Response and Communication(EERC) system; the system consists of a command center that represents the main control center for managing the emergency, a mobile application that runs on multiple mobile devices in the hands of responders in the eld, and an evacuation system that can run simulations of optimal evacuation patterns in the midst of dynamically changing conditions. The system employs a client-server architecture, using a PostgreSQL server and iPhone/iPod devices for the responders and command center to communicate with each other.

关键词：通信；地形编码；无线电系统；应急通信；城市地区

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关键词：光机电；机器人；自发服务

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To investigate robot Simultaneous Localization and Mapping (SLAM) in the unknown environment, the non-linear Interacting Multiple Model (IMM) SLAM algorithm is applied to solve the problem concerning the statistical property mutation of a system. The key point of this algorithm is to use non-linear Gaussian model to approximate non-linear and non-Gaussian model so that robot Simultaneous Localization and Mapping can be achieved. Each model employs the Extended Kalman Filter (EKF) algorithm to linearize the non-linear system and uses the non-linear Interacting Multiple Model algorithm in each step to get fusion estimated value. The Monte Carlo simulation results show that the proposed algorithm has better estimate precision.

关键词：光机电；机器人；自动控制系统；非线性；交互多模型

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This research project is focused on developing computational game theoretic techniques to tackle the design and computation of equilibrium power allocation/control schemes for a complex heterogeneous communication system. We have explored the use of noncooperative game theory, MPEC (Mathematical Programs with Equilibrium Constraints) to formulate and study the spectrum management problem. We have also addressed the design and computation complexities of equilibrium power spectrum policies in various game theoretic frameworks and proposed efficient distributed algorithms for dynamic power spectrum design.

关键词：通信；通信和无线电系统；博弈论；算法；均衡；资源管理

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This research develops collection and signal processing models to produce passive SAR ground images using OFDM communication networks. The OFDM- based WiMAX network is selected as a relevant example and is evaluated as a viable source for radar ground imaging. The monostatic and bistatic phase history models for OFDM are derived and validated with experimental single dimensional data. An airborne passive collection model is defined and signal processing approaches are proposed providing practical solutions to passive SAR imaging scenarios. Finally, experimental SAR images using general OFDM and WiMAX waveforms are shown to validate the overarching signal processing concept.

关键词：通信；通信网络；合成孔径雷达；无源雷达；雷达成像；OFDM

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Contrary to the assumptions underlying many current robot systems, teaching is an interactive process where the tutor needs to be continuously informed about the learner's internal states of understanding and perception. In an open ended learning situation this interaction can not be pre-modelled as the aspects that need clarification can not be foreseen. However, standard approaches do exactly this: they pre-define interactions by coupling system states with dialog acts. In our approach we target at losening this coupling between system and dialog states by providing general task and interaction patterns and means to relate them to each other. By this approach we are now able to provide on the one hand a dialog system that is relatively easily adaptable to new scenarios and on the other hand mixed-initiative interactions that allow the system to inform the tutor about internal representations when they become important for the interaction.

关键词：光机电；机器人；人机交互

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This report presents a method for running a dynamic legacy inlet simulation in concert with another dynamic simulation that uses a graphical interface. The legacy code, NASA's LArge Perturbation INlet (LAPIN) model, was coded using the FORTRAN 77 (The Portland Group, Lake Oswego, OR) programming language to run in a command shell similar to other applications that used the Microsoft Disk Operating System (MS-DOS) (Microsoft Corporation, Redmond, WA). Simulink (MathWorks, Natick, MA) is a dynamic simulation that runs on a modern graphical operating system. The product of this work has both simulations, LAPIN and Simulink, running synchronously on the same computer with periodic data exchanges. Implementing the method described in this paper avoided extensive changes to the legacy code and preserved its basic operating procedure. This paper presents a novel method that promotes inter-task data communication between the synchronously running processes.

关键词：通信；数据传输；并行处理；仿真模拟；遗留代码

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GAO has identified the protection of systems supporting the nation's critical infrastructure--which includes the communications sector--as a government-wide high-risk area. GAO was asked to (1) identify the roles of and actions taken by key federal entities to help protect communications networks from cyber-based threats, (2) assess what is known about the extent to which cyber incidents affecting the communications networks have been reported to the FCC and DHS, and (3) determine if Defense's pilot programs to promote cybersecurity in the defense industrial base can be used in the communications sector. To do this, GAO focused on core and access networks that support communication services, as well as critical components supporting the Internet. GAO analyzed federal agency policies, plans, and other documents; interviewed officials; and reviewed relevant reports.

关键词：通信；网络安全；计算机网络；公共安全；国家安全

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The General Dynamics (GD) S-Band software defined radio (SDR) in the Space Communications and Navigation (SCAN) Testbed on the International Space Station (ISS) will provide experimenters an opportunity to develop and demonstrate experimental waveforms in space. The GD SDR platform and initial waveform were characterized on the ground before launch and the data will be compared to the data that will be collected during on-orbit operations. A desired function of the SDR is to estimate the received signal to noise ratio (SNR), which would enable experimenters to better determine on-orbit link conditions. The GD SDR does not have an SNR estimator, but it does have an analog and a digital automatic gain control (AGC). The AGCs can be used to estimate the SDR input power which can be converted into a SNR. Tests were conducted to characterize the AGC response to changes in SDR input power and temperature. This purpose of this paper is to describe the tests that were conducted, discuss the results showing how the AGCs relate to the SDR input power, and provide recommendations for AGC testing and characterization.

关键词：通信；自动增益控制；无线电通信；SDR；宇宙空间站；太空通信

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