This thesis explores a novel network design concept to address the data and communications needs of the Department of Defense (DoD). Current and future military operations are increasingly reliant upon data connectivity to facilitate situational awareness and distribute vital information. Current infrastructures are insufficient to meet the growing demand, especially in the myriad austere environments where military forces operate. The DoD has become reliant upon increasingly vulnerable and expensive satellite communications to fill those gaps. The wireless data technologies utilized in the commercial sector to meet the data distribution requirements of business and commercial telecommunications providers can be leveraged and adapted to meet the connectivity requirements of the DoD. By pairing these technologies with developing HAPs and their capabilities the potential for a long-range wireless broadband solution emerges. This thesis evaluates broadband wireless data technologies in combination with High Altitude Platform (HAP) technologies. It proposes a network design concept to serve as a model for future research and the ultimate integration of HAPs into battlefield information architectures bringing the concepts of network centric warfare ever closer to reality.

关键词：无线计算机网络；宽带；通信和无线电系统；数据处理

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In Cognitive Radio Network (CRN),where Primary User (PU) and multiple Secondary Users (SUs) wish to communicate with their corresponding receivers simultaneously over fading channels,spectrum utilization and efficient resource allocation are both significant points for CRN.Interference between PU and SUs should be eliminated in order to realize spectrum sharing.Multi-user resource allocation with the target of maximizing the spectral efficiency of SUs and satisfying the proportional rate constraint between SUs are proposed under the conditions of total SU interference constraint.An adaptive low-complexity suboptimal algorithm for subcarrier and power joint allocation is presented based on Rate Adaptive (RA) criterion,where adaptive subcarrier allocation is performed by assuming equal power distribution,while each subcarrier is assigned in accordance with subcarrier efficiency function.Moreover,linear water-filling algorithm for power allocation is applied within each subcarrier.Simulation results indicate that,with the proposed adaptive subcarrier allocation,spectral efficiency of multiple SUs is superior to traditional subcarrier power joint allocation algorithm.Low computational complexity and adaptive features make it available for implementation.

关键词：认知无线电网络;自适应子载波分配;衰落信道

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network—at an estimated cost of about $3 billion per year indefinitely—to improve communication and other capabilities and to provide needed information to soldiers and commanders on the battlefield. The Army has identified this network as its number one modernization priority. For nearly 20 years, the Army has had limited success in developing its information network of sensors, software, and radios to give soldiers and commanders exact information when they need it, in any environment, and thus improve situational awareness and decision making in combat. To achieve this goal, the Army is implementing a new agile process

关键词：通信网络；军队人员；信息系统；测试

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System engineering practices for complex systems and networks now require that requirement, architecture, and concept of operations product development teams, simultaneously harmonize their activities to provide timely, useful and cost-effective products. When dealing with complex systems of systems, traditional systems engineering methodology quickly falls short of achieving project objectives. This approach is encumbered by the use of a number of disparate hardware and software tools, spreadsheets and documents to grasp the concept of the network design and operation. In case of NASA's space communication networks, since the networks are geographically distributed, and so are its subject matter experts, the team is challenged to create a common language and tools to produce its products. Using Model Based Systems Engineering methods and tools allows for a unified representation of the system in a model that enables a highly related level of detail. To date, Program System Engineering (PSE) team has been able to model each network from their top-level operational activities and system functions down to the atomic level through relational modeling decomposition. These models allow for a better understanding of the relationships between NASA's stakeholders, internal organizations, and impacts to all related entities due to integration and sustainment of existing systems. Understanding the existing systems is essential to accurate and detailed study of integration options being considered. In this paper, we identify the challenges the PSE team faced in its quest to unify complex legacy space communications networks and their operational processes. We describe the initial approaches undertaken and the evolution toward model based system engineering applied to produce Space Communication and Navigation (SCaN) PSE products. We will demonstrate the practice of Model Based System Engineering applied to integrating space communication networks and the summary of its results and impact. We will highlight the insights gained by applying the Model Based System Engineering and provide recommendations for its applications and improvements.

关键词：空间通信；通信网络;系统工程；数据整合；系统集成

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No abstract available.

关键词：云物理；大气化学；气象雷达；地面站；通信网络

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Rapidly deployable mobile bridges are of direct relevance to military and civilian agencies. The US Army uses such bridges in a broad range of applications including assault, tactical, and general communication. Civilian use extends from temporary infrastructure improvements during natural disasters to planned situations that are equally critical. This paper describes a modular bridge system developed primarily for use in assault scenarios where rapid deployment is vital, but this design concept is also relevant in civil applications. The robust metallic design of the bridge is based on an aluminum trussed arch reinforced by steel cables. The segmental form of the structure allows it to be folded into a compact package for transportation in a standard 40 ft container, which facilitates shipping by road, rail, sea, or air (C-130 transport aircraft). The bridge segments also facilitate adaptation of the bridge to different spans ranging from 8m to 32m. The load rating for these spans varies between 100T and 40T respectively. The preferred deployment approach for the assault configuration uses a scissor method in conjunction with a winching mechanism mounted on an auxiliary bridge guide. Compared to more conventional techniques, this method reduces the demands on the bridge launcher. The complete system provides an integrated solution to cover a broad spectrum of bridging applications. Extensive computer analysis was used to refine and optimize the components in the bridge. Structural testing of components during the design stage also helped guide the design process, and operational and load testing of a prototype system using strain gauging confirmed the integrity of the final design.

关键词：桥梁;结构特性;交通

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This article explains how Task Force Commando; 10th Mountain Division utilized both human factors and emerging technology to better utilize Unmanned Aircraft Systems throughout the Paktika Province on the 2013 deployment to Afghanistan s RC- East. Early in their deployment it was apparent to LTC Jason Bridges, Task Force Gladiator commander that communication between Route Clearance Platoons and UAS operators was insufficient. Despite having FM retrains capabilities on the aircraft which allows for extended FM communications, UAS operators and ground patrol leaders often could not communicate via FM due to atmospheric and mountainous terrain conditions.

关键词：通信网络;阿富汗；无人机；工作队；蒲福风级（蓝色因素跟踪器）

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Cloud computing is fast becoming an integral part of how we communicate with one another, buy music, share photos, conduct business, pay our bills, shop, and bank. Many of the activities that once occurred solely in the physical world, including communications with one another, are increasingly moving to the digital world. What was once a letter to a friend is now a Facebook message; a call to a loved one is now a Skype chat; a private meeting with a business partner is now a video conference call. In short, the cloud is revolutionizing not only how we compute, but also how we live. Where individuals once locked personal or business papers solely in a desk drawer or filing cabinet, they now also store them on someone elses computer. In short, cloud computing is a web-based service that allows users to access anything from e-mail to social media on a third-party computer.

关键词：云计算；隐私保护；社会通信；互联网；计算机辅助教学

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The number of control loops used in process industry is growing continuously, whilst manpower is being reduced. Consequently even companies that have embraced new control technologies struggle to maintain satisfactory performance over the long term. Numerous investigations have shown that the performance of control systems in the process industries is not satisfactory, as mentioned in Chap. 1. This particularly applies for the steel industry, where it is the norm to perform controller tuning only at the commissioning stage and then never again. A loop that worked well at one time is prone to degradation over time unless regular check and maintenance is undertaken.

关键词：钢铁；回路；控制系统；调试

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With the advancement of many off-the-shelf data acquisition systems readily available today and the availability of 3G and 4G highspeed wireless cellular networks, the potential for remote monitoring of critical bridges has never been better. Needs exist regarding scour and general structural response for long-term monitoring. However, short-term monitoring using quickly deployable, rugged systems are also desirable in cases where impact, fire, environmental effects, or other damage may occur. These robust systems can be deployed rapidly, and endure harsh elements, enabling DOTs to constantly assess and monitor a structure, or a network of structures. Hence, the objective of this project is to explore the feasibility and proof of concept of using a web-based bridge monitoring interface for use on selected INDOT bridges for both short-term and long-term applications. This report will focus on a single case study, the Virginia Ave Bridge over I-65 SB, a steel plate girder bridge that frequently falls victim to truck impact as a result of low clearance. This case study is uniquely different and provides insight into how targeted instrumentation systems can be used to probe specific parameters desired by owners for bridge condition assessment and monitoring. It will be shown how commercially available instrumentation systems can be tailored to fit any unique application required. Additionally, it will be demonstrated that INDOT benefited from this specific case of fielddeployed, short-term monitoring, which included automated notifications of critical onsite conditions.

关键词：钢铁;结构分析;土木工程;桥梁

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