In many simultaneous localization and mapping (SLAM) systems, it is desirable to exploit the fact that the system is traversing though a previously visited environment. Once these locations, commonly known as loop closures, have been detected the system must be able to both compute and verify the relative transformation between proposed locations. In this thesis we present two independent algorithms, using 2D LiDAR scanners, for robustly computing the transformation between arbitrary locations with overlapping geometry and validating the resulting transforms. First, a scan matching algorithm based on a genetic search and a fractional distance metric is presented. Secondly, two metrics are proposed to verify the recovered transforms. Through experimental results the proposed algorithms are shown to robustly estimate and validate loop closure transformations for both manually and automatically defined candidates. Finally, the proposed algorithms are demonstrated in an end-to-end SLAM framework.

关键词：即时定位；任意定位；二维激光扫描仪；算法

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There is a growing research tradition in the interface between Economics and Computer Science: Economic insights and questions about incentives inform the design of systems, while concepts from the theory of computation help illuminate classical Economics problems. This dissertation presents results in both directions of the intellectual exchange. Originally designed by industry engineers, the sponsored search auction has raised many interesting questions and spurred much research in auction design. For example, early auctions were based on a rst-price payment model and proved to be highly unstable | this dissertation explores how improvements in the bidding language could restore stability. We also show that a rst-price auction oers substantially better performance guarantees when a single advertiser may benet from multiple ads. Another interesting problem arises because sponsored search auctions must operate with limited information about a user's behavior | we show how sampling can maintain incentive compatibility even when the auctioneer incorrectly predicts the user's behavior.

关键词：经济学；计算机科学；广告；拍卖；支付

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Relational data has become so widespread that even end-users such as secretaries and teachers frequently interact with them. However, finding the right query to retrieve the necessary data from complex databases can be very difficult for end-users. Many of these users can be seen voicing their confusion on several Excel help forums, receiving little help and waiting days for responses from experts. In this paper, we present Quicksilver, a programming-by-demonstration solution that derives queries from user inputs. It is designed to be easy and intuitive for users who are not familiar with database theory. We present Quicksilver’s interface designs and synthesis algorithms. We conclude with a user study designed to evaluate Quicksilver’s performance.

关键词：关系型数据；数据库；Quicksilver

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关键词：软件教程；图操作教程；程序性知识；图片处理

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The goal of this paper is to present a formal connection between synthesis problems that have been considered,largely separately, in the two research communities of control engineering and formal methods. By making this connection mathematically precise, we hope to \bridge the gap" between two research areas that aim at tackling similar synthesis problems, but from di erent angles, and by emphasizing di erent, and often complementary, aspects. Such a formal bridge should be a source of inspiration for new lines of investigation that will leverage the power of the synthesis techniques that have been developed in these two areas.

关键词：反应合成；管理控制；弥合差距；合成技术

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The goal of this project is to develop an Android Phone App that can be used to measure dimensions of a room and overlay it with a Wi-Fi strength map. This is meant to address suboptimal arrangements of Wi-Fi router/access points, which result in a low speed/unstable/inaccessible Wi-Fi signal coverage in an indoor space. The motivation of the project is to reduce the cost of having a specialist to come to customers property to x Wi-Fi coverage problems. The App developed will enable Android users to identify such problems themselves for free.

关键词：安卓手机应用程序；无线网络；最优路径

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Unfortunately, the data independence provided by a traditional relational database system,while useful for agile development, only exacerbates the problem by hiding potentially expensive queries under simple declarative expressions. The disconnect between expression complexity and runtime cost often leads developers to mistrust the suitability of relationaldatabase systems for their web applications in the long term.

关键词：数据独立性；数据库系统；网络应用

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I present a method for decreasing the duration of artifacts present during intracortical microstimulation (ICMS) recordings by using techniques developed for digital communications. I use a Zero-Forcing Equalizer (ZFE) to shape a stimulus pattern with the aim of reducing artifact length. The results find that using the ZFE stimulus has the potential to reduce artifact duration by more than 70%. Continuing work and current considerations for the hardware implementation of the equalizer are presented.

关键词：工件；数字通信；硬件；Zero-Forcing均衡器(ZFE)

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Simulation of electronic transport in nanoscale devices plays a pivotal role in shedding light on underlying physics, and in guiding device-design and optimization.The length scale of the problem and the physical mechanism of device operation guide the choice of formalism. In the sub-20 nanometer regime, semi-classical approaches start breaking down, thus necessitating a quantum-mechanical treatment of the electronic transport problem.

关键词：低功耗；米级设备；非平衡格林函数；模拟；纳米电子传输设备

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Levels of literacy and the variance in them, continue to be a problem in the world. These problems are ubiquitous in the sense that they change form from developing to developed regions, but do not seize to exist. For example, while teacher absenteeism is a fairly large problem in the developing world, student motivation can pose challenges in the developed world. Prior research has demonstrated that games can serve as an efficient medium in bridging these literacy gaps, generating student motivation (or engagement) not just in short term but also in the long term. This dissertation is dedicated to the investigation and application of spoken language technology to language acquisition contexts in the developed world. We explore the broader research question in two major contexts.

关键词：语言技术；语言环境；语音激活系统

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