Mining Spatial Associations with Limited Sensory Information

Abstract

Human navigation in an unknown environment requires an understanding of the spatial relationships of the terrain. For example, a soldier who is on a reconnaissance mission in a new city needs to “know” the spatial layout of the surroundings with high confidence. Oftentimes, this understanding must be acquired within a very short amount of time and with limited sensory inputs. The soldier would benefit from a digital avatar that draws inferences about the spatial layout of the city based on an initial set of observations and guides the soldier either in further exploring the environment or in making decisions based on these inferences. In this paper, we present and evaluate an inductive approach to learning spatial associations using sensory data that is available from the simulation environment of a computer game, Unreal Tournament. We study two kinds of spatial relationships between nodes on a level of a game map: nodes that are placed near each other to satisfy some spatial requirement and nodes that are placed near each other to satisfy the design preferences of a level architect. We show that we can infer both kinds of relationships using an association rule mining algorithm. Furthermore, we show how to use an ontology to distinguish between these relationships in order to discover different types of spatial arrangements on a specific map. We discuss how the inferred associations can be used to control an avatar that makes recommendations for navigating unexplored areas on a map. We conclude with some thoughts on the applicability of our methods to scenarios in the real world, beyond the simulation environment of a game, and on how the learned associations can be represented and queried by a simple question-answer type system.     

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一种基于实数域特征值分解的前后向平滑算法

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Matching suitable feature construction for SAR images based on evolutionary synthesis strategy

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The role of space related non-governmental organizations (NGOs) in capacity building

Non-governmental organizations (NGOs) play a unique role in international affairs, providing access to resources, expertise, and assistance to supplement State resources. Sometimes the diplomatic skills and unofficial access of NGOs to policymakers through Track Two diplomacy can move a previously stalled critical issue forward and assist policymakers from different countries to find common ground outside official channels. Because they work outside of official channels, they are not bound by State policy that may inhibit negotiations between States. Some also have a convening power that sometimes makes it possible for State representatives to meet discipline experts and each other for informal discussions on issues of mutual interest. Finally, NGOs can draw attention to issues that may be overlooked or avoided by State organizations.     

Hilbert空间中严格伪压缩映像的强收敛定理

给出了一种求解严格伪压缩非自身映像不动点集上变分不等式的迭代算法，并证明了其强收敛性。此结果推广了姚永红和T．H．Kim等的研究结果。最后，进一步将结论推广到求解有限个严格伪压缩非自身映像公共不动点集上的变分不等式。     

大航向角误差情况下飞行中对准研究

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一种扩展的比例导引规律及其弹道方程的构建

在传统的动力学微分方程的基础上提出了一种扩展的比例导引法 ,并给出了该导引规律下的相对弹道方程。文中的推理过程表明 ,这种导引规律对导弹、目标的运动速度几乎没有限制 ,理论上说明运用该制导规律的导弹将能对付高机动大速度目标 ,其弹道方程的建立 ,使得研究该制导规律下的弹道特性成为可能。     

Beam-Park-Experiment-1/2000 with TIRA

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根据两颗导航星信息估计捷联惯导系统误差的一种方法

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