Data fusion has become an active research topic in recent years. Growing computational performance has allowed the use of redundant sensors to measure a single phenomenon. While Bayesian fusion approaches are common in general applications, the computer vision field has largely relegated this approach. Most object following algorithms have gone towards pure machine learning fusion techniques that tend to lack flexibility. Consequently, a more general data fusion scheme is needed. Within this work, a hierarchical Bayesian fusion approach is proposed, which outperforms individual trackers by using redundant measurements. The adaptive framework is achieved by relying on each measurement's local statistics and a global softened majority voting. The proposed approach was validated in a simulated application and two robotic platforms.
This work aims to create a general Bayesian approach for real-time applications in robotic platforms. The proposed method processes the bounding boxes of the trackers detectors as sensor measurements. This framework is founded in the basis of the bank of KFs with some similarities with the mixture of experts aforecited. Furthermore, this scheme addresses some common problems such as data imperfection, outliers and spurious data, measurement delays, static vs. dynamic phenomena, and others discussed in @cite_32 . Additionally, this approach was tested in simulated signals and two different robotics platforms: An UAV system and a pan-tilt system. Both are capable of following a target. While similar approaches have used vision-based trackers to control a small UAV in @cite_15 @cite_0 and @cite_3 . Previous works did not consider the fusion of several methods at a bounding box level to improve reliability over longer time spans.
@cite_0 @cite_15 @cite_32 @cite_3
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We present a solution to repeatability assessment of an arm gesture recognition system using multiple orientation sensors. We focus specifically on the problem of controlling unmanned aerial vehicles (UAVs) in the presence of manned aircrafts on an aircraft deck. Our goal is to design a robust UAV control with the same gesture signals as used by current flight directors for controlling manned vehicles. Given the fact that such a system has to operate 24 hours a day in a noisy and harsh environment, for example, on a Navy carrier deck, our approach to this problem is based on arm gesture recognition rather than on speech recognition. We have investigated real-time and system design issues for a particular choice of active sensors, such as, the orientation sensors of the IS-300 Pro Precision Motion Tracker manufactured by InterSense. Our work consists of (1) scrutinizing sensor data acquisition parameters and reported arm orientation measurements, (2) choosing the optimal attachment and placement of sensors, (3) measuring repeatability of movements using dynamic time warping (DTW) metric, and (4) testing performance of a template-based gesture classification algorithm and robot control mechanisms, where the robot represents an UAV surrogate in a laboratory environment. The fusion of multi-sensor information for state estimation is a well studied problem in robotics. However, the classical methods may fail to take into account the measurements validity, therefore ruining the benefits of sensor redundancy. This work addresses this problem by learning context-dependent knowledge about sensor reliability. This knowledge is later used as a decision rule in the fusion task in order to dynamically select the most appropriate subset of sensors. For this purpose we use the Mixture of Experts framework. In our application, each expert is a Kalman filter fed by a subset of sensors, and a gating network serves as a mediator between individual filters, basing its decision on sensor inputs and contextual information to reason about the operation context. The performance of this model is evaluated for altitude estimation of a UAV. A citing sentence is one that appears in a scientific article and cites previous work. Citing sentences have been studied and used in many applications. For example, they have been used in scientific paper summarization, automatic survey generation, paraphrase identification, and citation function classification. Citing sentences that cite multiple papers are common in scientific writing. This observation should be taken into consideration when using citing sentences in applications. For instance, when a citing sentence is used in a summary of a scientific paper, only the fragments of the sentence that are relevant to the summarized paper should be included in the summary. In this paper, we present and compare three different approaches for identifying the fragments of a citing sentence that are related to a given target reference. Our methods are: word classification, sequence labeling, and segment classification. Our experiments show that segment classification achieves the best results. Scholars are increasingly citing electronic web references which are not preserved in libraries or full text archives. WebCite is a new standard for citing web references. To webcite a document involves archiving the cited Web page through www.webcitation.org and citing the WebCite permalink instead of (or in addition to) the unstable live Web page. This journal has amended its instructions for authors accordingly, asking authors to archive cited Web pages before submitting a manuscript. Almost 200 other journals are already using the system. We discuss the rationale for WebCite, its technology, and how scholars, editors, and publishers can benefit from the service. Citing scholars initiate an archiving process of all cited Web references, ideally before they submit a manuscript. Authors of online documents and websites which are expected to be cited by others can ensure that their work is permanently available by creating an archived copy using WebCite and providing the citation information including the WebCite link on their Web document(s). Editors should ask their authors to cache all cited Web addresses (Uniform Resource Locators, or URLs) prospectively before submitting their manuscripts to their journal. Editors and publishers should also instruct their copyeditors to cache cited Web material if the author has not done so already. Finally, WebCite can process publisher submitted citing articles (submitted for example as eXtensible Markup Language [XML] documents) to automatically archive all cited Web pages shortly before or on publication. Finally, WebCite can act as a focussed crawler, caching retrospectively references of already published articles. Copyright issues