A DCS is an automated control system that, rather than being centralized, is distributed across an entire organization. DCS are distributed in such a way that each component or sub-system of a manufacturing plant is controlled by one or more controllers, thereby providing instructions to different parts of the plant.

关键词：EMEA；DCS；分布式控制系统

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The California Department of Transportation (Caltrans) has contracted with the Western Transportation Institute (WTI) at Montana State University (MSU) to develop an Automated Safety Warning Controller. The controller will interface with roadside devices such as sensors and signs. The controller will allow for automated data collection and application of best practice algorithms to analyze sensor data and to actuate related warning messages to motorists. For instance, wind warning messages might be actuated on a changeable message sign (CMS) when wind speed, as read from a sensor, exceeds a given threshold. The controller allows for remote access and administration via standard IP-based connections established through POTS dialup or direct connection to wired access points, but is not dependent on those connections for operation. In other words, the controller will remain locally operable in the event that outside communication is unavailable for whatever reason. Even if a communication link to the outside is unavailable, the controller will continue to monitor and control its associated devices. This functionality is especially important in rural areas where weather conditions make communications services unreliable when the functionality is needed most. The standardized use of such a device would likely result in decreased maintenance costs, improved reliability, and greater flexibility in implementation when compared with one-of-a-kind deployments.

关键词：预警系统;安全设备;流量控制;自动化;算法;通信

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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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关键词：战略规划;通信;事故预防;干预措施

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Researchers in the area of cognitive radio often investigate the utility of dynamic spectrum access as a means to make more efficient use of the radio frequency spectrum. Many studies have been conducted to nd ways in which a secondary user can occupy spectrum licensed to a primary user in a manner which does not disrupt the primary user's performance. This research investigates the use of opportunistic access in a frequency hopping radio to mitigate the interference caused by other transmitters in a contentious environment such as the unlicensed 2.4 GHz region. Additionally, this work demonstrates how dynamic spectrum access techniques can be used not only to prevent interfering with other users but also improve the robustness of a communication system.

关键词：认知无线电;通讯和广播系统;动态频谱接入;节能检测;

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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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In biology textbooks, we are taught to believe that biology is all about chemical reactions. However, recent discovery of electromagnetic sensing and antenna like communication of key biomaterials demand for the existence of a world of physical communication and energy exchange squarely parallel to the chemical only biology believed to date. This finding suggests that so-called safe mobile communications /201100 kHz to 300 GHz/202 across the globe are not safe anymore. The discovery noted above also unravels that from basic protein molecules to the giant biological structure; every part of an integrated biological system absorbs and radiates to communicate in a distinct frequency band. This means, multiple frequency bands operate simultaneously in a biological system and if energy is injected at a local part of any band is distributed all over the entire system. Thus, the biological operational mechanisms and its evolutions are not discrete events as we are taught. Even a linguistic conversation using sound can affect a molecular scale phenomenon and rhythms are eventual expressions that emerge from those molecules. Thus, biological systems like our brain, organs change in every living life form at every moment, define and redefine rhythms of our life /201e.g. circadian, cardiac/202 according to our environment. Our objective is to develop the algorithm that correlates the environment, biological rhythms and the molecular dynamics at the atomic scale, the triangular connecting route will create a new biology, observed but never seen before.

关键词：生物信息处理;脑;通信和广播系统;细胞学

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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 Federal Communications Commission (FCC) has established buildout requirements-which require a licensee to build the necessary infrastructure and put the assigned spectrum to use within a set amount of time-for most wireless services, including cellular and personal communication services. FCC tailors the buildout requirements it sets for a wireless service based on the physical characteristics of the relevant spectrum and comments of stakeholders, among other factors. Therefore, buildout requirements vary across wireless services. For example, a buildout requirement can set the percentage of a license's population or geographic area that must be covered by service or can describe the required level of service in narrative terms rather than numeric benchmarks. Buildout requirements also vary by how much time a licensee has to meet a requirement and whether it has to meet one requirement or multiple requirements in stages. FCC's enforcement process for wireless-service licenses with buildout requirements primarily relies on information provided by licensees, and FCC followed its process for the five wireless services GAO reviewed. Specifically, FCC requires licensees to self-certify that they have met buildout requirements. If a licensee does not do so, FCC automatically terminates the license. Some stakeholders GAO interviewed said that self-certification is an effective way for FCC to enforce buildout requirements because it is public and transparent. GAO examined FCC license data for five wireless services and found that buildout requirements were met for 75 percent of those licenses, and FCC generally terminated those that did not. As part of enforcement, FCC also grants or dismisses licensees' requests to extend the deadline for meeting a requirement. FCC may grant an extension if the licensee shows that it cannot meet a deadline due to causes beyond its control, like a lack of available equipment. For the five wireless services examined, GAO found that extensions were requested for 9 percent of licenses, and FCC granted 74 percent of these requests. FCC officials said that the Commission seeks to be aggressive but pragmatic when enforcing buildout requirements, including being flexible on deadlines when needed. Some licensees and industry associations GAO interviewed said that extensions can provide needed flexibility when unexpected problems occur. Some concerns were raised, however, that granting extensions can undermine buildout requirements by creating an impression that they will not be strictly enforced.

关键词：数据收集;通信;战略规划;电信;电信业

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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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