This report presents the two-dimensional (2D) version of the Automated Velocity Obstacle Collision Avoidance (AVOCA) system. AVOCA is a platform independent, distributed collision avoidance system for multi-agent environments. AVOCA requires minimal communication between agents, with plans to extend into sensor based agent recognition in future work. AVOCA uses well- founded velocity obstacle approaches that have been enhanced for the AVOCA system. Additionally, AVOCA uses the novel kinematic velocity obstacle (KVO) to account for agent kinematics in its calculations, also presented in this report. Results are presented for both simulations and physical experimentation, which demonstrate both the system's ability to guide agents without collision in the vast majority of cases and the effectiveness of KVOs in general.

关键词：六自由度仿真; AMCL（自适应蒙特卡罗定位）;自主导航;自主操作

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The report presents the results of a survey of safety culture in three Norwegian haulier companies, which are selected based on an assumption that they have good safety culture. The study supports the assertion that the companies have good safety cultures. This especially applies to Company A, which has the highest safety culture score of the three companies, and which also have a higher safety culture score than we have found in other transport sectors. This is probably due to the fact that Company A transports dangerous goods, which is a line of transport which has particular framework conditions favoring safety. The accident involvement of the drivers were in accordance with the companies score on the safety culture index. Analyzing the data on the three companies work on safety, we have identified the following common characteristics of good safety work in haulier companies: 1) Follow up of drivers speed, seat belt use and driving style, 2) Managers and employees safety commitment, 3) Predictability, 4) Organization of transport assignments, 5) Pay system, 6) Control of drivers compliance with regulations related to drive and rest, 7) Safety training/education, 8) Arenas for communication about safety, 9) Reporting culture and systems, and 10) Safety management system: a) risk analyses, b) procedures, c) training.

关键词：基础设施;通信;安全管理;交通运输安全

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In 2012, the Office of the National Coordinator for Health Information Technology (ONC) conducted a nationally representative telephone survey of 2,050 adult individuals, in both English and Spanish. The survey focused on their privacy and security attitudes, in particular when their health information is stored or transmitted electronically via EHRs and HIE. This data brief reports individuals perceptions about the measures put in place by providers to protect EHRs, and its association with support for EHRs, HIE and patient-provider communication.

关键词：电子健康档案;患者;医疗保健提供者;隐私;信息交流;

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Mobile devices provide civilians with a convenient way to communicate on a day-to-day basis. However, their centralized infrastructure can be interrupted at critical times such as during natural disasters. While this cellular infrastructure may not be available in environments, such as the battlefield, these ubiquitous devices could exploit ad-hoc mode communication to be of use. The Army has identified several military applications for ad-hoc networks of mobile devices, including communication between dismounted Soldiers, facial recognition, and situation awareness. Many of these applications require more capabilities than most mobile devices possess, or would prove to be a burden on the limited battery lives of these devices. Thus, offloading computation to a more capable machine has been identified as a means to make these devices useful while mitigating their weaknesses. This has lead Army researchers to develop novel algorithms to improve the offloading process. Although these algorithms have been tested via simulation, a working implementation is necessary to fully evaluate them. This report discusses the state of ad-hoc mode communication on Android devices, and describes the procedure for enabling ad-hoc mode, which is often not available by default. It goes on to describe techniques for studying multiple aspects of the network and its behavior.

关键词：算法;机器人;陆军;蜂窝通信;通信和广播系统

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Over the past decade, several technological advances have allowed Global Navigation Satellite Systems (GNSS) receivers to have the capability to record displacements at high frequencies, with sampling rates approaching 100 samples per second (sps). In addition, communication and computer hardware and software have allowed various institutions, including the U.S. Geological Survey (USGS), to retrieve, process, and display position changes recorded by a network of GNSS sites with small, less than 1-s delays between the time that the GNSS receiver records signals from a constellation of satellites and the time that the position is estimated (a method known as real-time). These improvements in hardware and software have allowed the USGS to process GNSS (or a subset of the GNSS, the Global Positioning System, GPS) data in real-time at 1 sps with the goal of determining displacements from earthquakes and volcanoes in real-time. However, the current set of GNSS equipment can record at rates of 100 sps, which allows the possibility of using this equipment to record earthquake displacements over the full range of frequencies that typically are recorded by acceleration and velocity transducers. The advantage of using GNSS to record earthquakes is that the displacement, rather than acceleration or velocity, is recorded, and for large earthquakes, the GNSS sensor stays on scale and will not distort the observations due to clipping of the signal at its highest amplitude. The direct observation of displacement is advantageous in estimating the size and spatial extent of the earthquake rupture. Otherwise, when using velocity or acceleration sensors, the displacements are determined by numerical integration of the observations, which can introduce significant uncertainty in the estimated displacements.

关键词：计算机软件;数据处理;位移;全球定位系统;导航卫星;

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We generate high-purity correlated and entangled photon- pairs at the telecom wavelengths in a cooled 10-meter highly nonlinear fiber (HNLF). In our previous project (contract no: FA8750-12-1-0136), we were able to generate correlated/entangled photon-pair using the highly nonlinear fiber in a counter-propagating scheme (CPS). With the HNLF at room temperature, we obtain coincidence-to-accidental ratio (CAR) approximately 26-30 and two-photon interference with visibility approximately 92-93. This is the best performance compared to the reported results in the literature on HNLF and Photonic Crystal Fiber (PCF) at telecom wavelengths. Unlike the PCF or microstructure fiber, the HNLF can be cooled at liquid nitrogen temperatures (77K) to suppress Raman photons. By cooling the HNLF, we expect to obtain a CAR approximately 130 and two-photon interference with visibility > 98. We will verify the non-local behavior of high-purity HNLF-based entangled photon-pairs by making Bell's Inequalities measurements. We investigate the effect of multiple scattering on the telecom wavelength photon-pair. Our findings show that quantum correlation of polarization-entangled photon-pairs is better preserved than polarization-correlated photon-pairs in multiple scattering processes.

关键词：频率;高度非线性光纤;通信;非线性系统

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The U.S. Geological Survey and the National Aeronautics and Space Administration are cooperatively investigating the utility of unmanned vehicles for near-real-time autonomous surveys of geophysical data collection. Initially focused on unmanned ground vehicle collection of magnetic data, this cooperative effort has brought unmanned surveying, precision guidance, near-real-time communication, on-the-fly data processing, and near-real-time data interpretation into the realm of ground geophysical surveying, all of which offer advantages over current methods of manned collection of ground magnetic data. An unmanned ground vehicle mission has demonstrated that these vehicles can successfully complete missions to collect geophysical data, and add advantages in data collection, processing, and interpretation. We view the current experiment as an initial phase in further unmanned vehicle data-collection missions, including aerial surveying.

关键词：航测;数据收集;地球物理数据;地面车辆;磁数据

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The objective of this research is to explore the technical soundness of a very large, cross-shaped, parabolic, sparse aperture antenna extending 75 m from the bus. Specifically, describing the environment of the satellite, the effect of fabrication error on the structure and the remaining error budget for the system. The methodology involves creation of an ideal truss structure, to which all others are compared. A uniform distribution of proportional errors up to 1e-5 is introduced into the truss members. lengths and the models are subjected to a static Finite Element Analysis. A solution for the surface normal error is addressed using Lagrange multipliers. The goal is to hold the surface normal error for the entire satellite below a root mean square of 15 mm. The analysis yields a surface error of less than 1.53 mm, well within requirements. Despite the enormous size of the antenna reflector, and tight diameter/surface error ratio of 10,000 required for L-band communication, the system seems feasible. The values achieved for truss induced surface errors are in line with established techniques for analyzing full aperture, and strip, mesh antennas. With the mesh reflector and truss largely defined, nearly half of the 15 mm error budget remains.

关键词：空军研究;天线孔径;天线阵列;通信卫星

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Most communication in the modern era takes place over some type of cyber network, to include telecommunications, banking, public utilities, and health systems. Information gained from illegitimate network access can be used to create catastrophic effects at the individual, corporate, national, and even international levels, making cyber security a top priority. Cyber networks frequently encounter amounts of network traffic too large to process real-time threat detection efficiently. Reducing the amount of information necessary for a network monitor to determine the presence of a threat would likely aide in keeping networks more secure. This thesis uses network traffic data captured during the Department of Defense Cyber Defense Exercise to determine which features of network traffic are salient to detecting and classifying threats. After generating a set of 248 features from the capture data, feed-forward artificial neural networks were generated and signal-to-noise ratios were used to prune the feature set to 18 features while still achieving an accuracy ranging from 83- 94. The salient features primarily come from the transport layer section of the network traffic data and involve the client/server connection parameters, size of the initial data sent, and number of segments and/or bytes sent in the flow.

关键词：通信和广播系统;通信网络;数码网络;控制论;特征选择;

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关键词：战略规划;通信;事故预防;干预措施

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