This study examines the travel behaviour and attitudes of recently resettled refugees in Chittenden County, Vermont, with particular attention to distinctions based on gender and age. It is based on an earlier project conducted between 2008-2012 that examined transportation practices amongst recently arrived refugees in Vermont as a generalized group. One of the findings from that initial study was that more in-depth research was necessary in order to understand the ways in which mobility and access to transportation impact specific parts of the refugee population, especially women, children and the elderly. Drawing on qualitative research methods using techniques such as interviews, focus groups, and surveys, this current study examines what kinds of possibilities and various exist to full mobility for these sub sets of the refugee population. In addition one of the key goals of this project was to examine what particular mode choices were favored by refugees both within the larger community but also within these subgroups of the population. The study found that there are indeed some significant differences based on age and gender of travel patterns, choices and options for men, women and seniors in the newly resettled refugee communities. In particular while both women and the elderly within refugee families often had nominal access to a car, very few had driver's licenses and most described a dynamic where male family members were the primary (or only) drivers. Women and the elderly also showed greater levels of willingness to embrace alternative modes of travel, especially walking and using transit than the general male refugee population. However, both groups echoed the sense within the refugee community as a whole that private vehicle ownership was an important component of a successful acculturation experience. They explained this due to the greater levels of independence, flexibility, and self-sufficiency that cars provided in their lives.

关键词：交通模式;司机行为;访问;年龄;社区;性别;流动性;人口;研究方法;调查;交通系统;佛蒙特州

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The overall goal of this project is to enhance the fundamental understanding of Florida long-distance travel characteristics, and to provide policy implications for long-distance transportation planning in the future. To achieve the research goal, this study first conducts a descriptive analysis of long-distance travel with special emphasis on the modes used, distance traveled, and origins and destinations. Then, this study estimates mode choice models for long-distance travel that are sensitive to alternative specific attributes and traveler characteristics. It is important to have appropriate models that are able to provide accurate predictions of travelers mode choice behavior that consider how people choose one mode or another. The descriptive analysis shows that nearly 90 percent of trips are made by personal passenger cars, and most are on I-4, I-95, and Turnpike corridors that connect the Tampa, Orlando, and Miami/Fort Lauderdale urbanized areas as defined by Metropolitan Statistical Area (MSA). Among MSAs in Florida, Orlando is the hub for long-distance travel. The estimated model shows that both travel time and travel cost decrease car users utility, indicating that people will have a greater chance to shift to other modes as travel time and travel costs increase. In contrast, air travel has a positive sign for travel time, and a negative sign for travel cost, while bus has a negative coefficient for travel time and a positive sign for travel cost. Positive signs of these estimated parameters may imply that air travelers and bus users are willing to increase travel time and travel cost, respectively.

关键词：旅行时间;交通系统;佛罗里达航空运输;汽车;成本

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Navigation requires knowledge of current location and a planned destination. This is true with manned vehicles and unmanned vehicles. There are many ways to acquire the current location, including global positioning system (GPS), triangulation, radar, and dead reckoning. Today GPS is the most reliable and accurate navigation technique when there is a clear, unobstructed view of the satellite constellation. Various sensors can be used to perform indoor navigation; however, when the vehicle is autonomous the sensors need to provide the exact location to the system. This research determined if using a template replay strategy has the same RNR performance as using an analog noise source. Using the template replay approach, each RNR node has a priori knowledge about the transmitted waveforms of other nodes. The analysis here revealed that modifications do not significantly alter RNR functionality. The analysis revealed that even at SNIR equal to 0 dB, there are no parameters that can be reliably extracted other than transmitted signal bandwidth and transmitted template length; the transmitted message length was able to be extracted because the message was repeated over and over. If the message was not replayed the analysis showed that there would be no ability to extract parameters. Finally, by using the RNR to transmit digitally generated templates, digital communication is possible and the symbol error rate (SER) is traceable to simulated SER.

关键词：自主导航;数字通信;室内导航;截获概率低;多基地雷达

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The emerging wireless world is expected to be characterized from the demand for new, diversified applications/services, the expanded use of wireless and the need for increased efficiency in resource provisioning and utilization. Therefore, the resource usage in an opportunistic manner would provide a solution towards this direction. Opportunistic networks (ONs) and Cognitive Management Systems (CMSs) for cellular extensions are one of the emerging communication paradigms in wireless mobile communications. For the cooperation of CMSs, specific mechanisms need to be defined in order to increase the accuracy of obtained knowledge on the context of the operational environment. Also, a cooperation mechanism is required for efficient coordination between the infrastructure and the devices in the scope of an ON. Therefore, Control Channels (CCs) are required for the exchange of information and the coordination between CMSs. Consequently, this work focuses on the definition of the needed interfaces that are introduced in order to enable communication between the cognitive management systems and also to the related groups of information that is needed to be conveyed between these systems in order to ensure proper interaction. Finally, an indication of the amount of information conveyed through CCs is provided in order to be able to assess the impact to the network of control-related transmitted information.

关键词：无线通信；互联网；认知管理系统；机会网络

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Recent investigations into the fundamental limits of mobile ad hoc networks have produced a physical layer method for approaching their capacity. This strategy, known as interference alignment, requires cooperation, rather than competition, among the transceivers in the network. Under ideal circumstances, every user can achieve reliable communication at rates approaching one half of the interference-free capacity. Unfortunately, prior research on interference alignment makes many assumptions that make it difficult to realize interference alignment in practice. This report summarizes the PI's work on realizing interference alignment in multiple-input multiple-output (MIMO) communication channels. The emphasis is on networks where clusters of users cooperate together, since this provides a good balance between network overhead and performance. One contribution was to devise a way to add new users to an existing cluster of interference aligned users. Different algorithms were devised as a function of the number of antennas in the network. Another contribution was to analyze interference alignment in a network with random clusters of users. The cases where interference alignment was preferred to other simpler communication strategies was characterized. Another contribution was to determine the impact of distributing the antennas. It was found that distributed antennas lead to higher performance with interference alignment, and new algorithms were designed to achieve that performance. A final contribution was to prototype an interference alignment network. A distributed prototype was constructed with over-the-air synchronization and feedback, demonstrating the viability of interference alignment for small networks in practice.

关键词：天线;集群;通信和广播系统;通信网络

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关键词：可重构系统；通信；吞吐量

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The use of individual Global Navigation Satellite Services (GPS, GLONASS, Galileo, and Beidou/COMPASS) for the position, navigation, and timing in the Space Service Volume at altitudes of 300 km, 3000 km, 8000 km, 15000 km, 25000 km, 36500km and 70000 km.

关键词：导航卫星；航天通信；全球定位系统；Glonass系统；卫星跟踪

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Information and communication technologies (ICT), like all technologies, are catalysts for political change and potential conflict. The Internet effect continues to fuel the explosive growth of ICT, and has enduring implications. It has sparked the long fuse of an Information Revolution and a Social Network Revolution. This revolutionary wave is fundamentally altering both the structure of institutional arrangements and the behavior of bureaucratic organizations by transforming traditional tactics for organizing, communicating, collaborating, and participating in the political system. Does the accelerated rate of systemic change caused by the Internet effect create social cohesion, or cleavages that may lead to increased conflict. The purpose of this study is to determine, by qualitative as well as quantitative means, whether a causal relationship exists between the degree a society is connected via social media networks (Internet and the World Wide Web WWW) and the institutional capacities of central governance. Blending theory with data, a statistical regression model is developed to evaluate the degree and measure the magnitude of this relationship. The findings gleaned from this analysis suggest that a conditional causal relationship does exist between social connectivity and state capacity.

关键词：互联网;社交沟通;通信和广播系统;测量

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The AeroMACS (Aeronautical Mobile Airport Communications System), which is based on the IEEE 802.16-2009 mobile wireless standard, is envisioned as the wireless network which will cover all areas of airport surfaces for next generation air transportation. It is expected to be implemented in the 5091-5150 MHz frequency band which is also occupied by mobile satellite service uplinks. Thus the AeroMACS must be designed to avoid interference with this incumbent service. Simulations using Visualyse software were performed utilizing a global database of 6207 airports. Variations in base station and subscriber antenna distribution and gain pattern were examined. Based on these simulations, recommendations for global airport base station and subscriber antenna power transmission limitations are provided.

关键词：移动通信系统;天线增益;航空运输;无线通信;仿真;

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During Phase one Option period, Trex performed extensive research into THz-range passive and active component that will be required make the Phase two hardware. The design of a custom MMIC was completed so it could be ordered processed with the once a year Pizza mask process at UMS. These parts are expected to arrive later this year when the Phase 2 contract is awarded and results in a significant cost saving in the development of a custom mixer. In addition the source pricing for the MMIC amplifier was also completed. This process took much longer than expected and this will speed up the process of betting parts during the second phase of the program. In addition direction of the overall mechanical configuration was outlined to speed up the process for the detailed design that will be undertaken in the next phase of the program. The radios will be designed to communicate in a half-duplex at 3 Gbps and full duplex using TDD mode at 1 Gbps data rate. The details of the TDD mode being much more complex were looked into in more detail during the option phase.

关键词：毫米波千兆; 通信;收发器;无线链路

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