124 research outputs found
Processing and initial comparison of PSR data from CAMEX-3 to SSM/I and TMI data
A multiband Polarimetric Scanning Radiometer (PSR) was integrated on a NASA DC-8 aircraft and flown from August through September of 1998 during the third Convection and Moisture Experiment (CAMEX-3). The PSR is a new conically-scanning imaging radiometer with channels at 10.7, 18.7, 21.5, 37.0 and 89.0 GHz, including both vertical and horizontal polarizations at each of these frequencies. These channels correspond to several key sensing bands of the DMSP (Defense Meteorological Satellite Program) SSM/I (Special Sensor Microwave Imager) and the NASA TRMM (Tropical Rainfall Measuring Mission) TMI (TRMM Microwave Imager). The PSR was developed by Georgia Institute of Technology and the NOAA Environmental Technology Laboratory and is the first airborne imaging radiometer to provide a research quality dataset of high spatial resolution multiband polarimetric microwave imagery within and around a hurricane. The authors describe the processing and calibration of the PSR CAMEX-3 dataset. They also provide a qualitative analysis and comparison of the PSR imagery to the SSM/I and TMI with specific regard to the spatial structure of a hurricane eyewall and surrounding rainbands.Peer ReviewedPostprint (published version
Visualising the structure of document search results: A comparison of graph theoretic approaches
This is the post-print of the article - Copyright @ 2010 Sage PublicationsPrevious work has shown that distance-similarity visualisation or ‘spatialisation’ can provide a potentially useful context in which to browse the results of a query search, enabling the user to adopt a simple local foraging or ‘cluster growing’ strategy to navigate through the retrieved document set. However, faithfully mapping feature-space models to visual space can be problematic owing to their inherent high dimensionality and non-linearity. Conventional linear approaches to dimension reduction tend to fail at this kind of task, sacrificing local structural in order to preserve a globally optimal mapping. In this paper the clustering performance of a recently proposed algorithm called isometric feature mapping (Isomap), which deals with non-linearity by transforming dissimilarities into geodesic distances, is compared to that of non-metric multidimensional scaling (MDS). Various graph pruning methods, for geodesic distance estimation, are also compared. Results show that Isomap is significantly better at preserving local structural detail than MDS, suggesting it is better suited to cluster growing and other semantic navigation tasks. Moreover, it is shown that applying a minimum-cost graph pruning criterion can provide a parameter-free alternative to the traditional K-neighbour method, resulting in spatial clustering that is equivalent to or better than that achieved using an optimal-K criterion
TaskMAD: a Platform for Multimodal Task-Centric Knowledge-Grounded Conversational Experimentation
The role of conversational assistants continues to evolve, beyond simple voice commands to ones that support rich and complex tasks in the home, car, and even virtual reality. Going beyond simple voice command and control requires agents and datasets blending structured dialogue, information seeking, grounded reasoning, and contextual question-answering in a multimodal environment with rich image and video content. In this demo, we introduce Task-oriented Multimodal Agent Dialogue (TaskMAD), a new platform that supports the creation of interactive multimodal and task-centric datasets in a Wizard-of-Oz experimental setup. TaskMAD includes support for text and voice, federated retrieval from text and knowledge bases, and structured logging of interactions for offline labeling. Its architecture supports a spectrum of tasks that span open-domain exploratory search to traditional frame-based dialogue tasks. It's open-source and offers rich capability as a platform used to collect data for the Amazon Alexa Prize Taskbot challenge, TREC Conversational Assistance track, undergraduate student research, and others. TaskMAD is distributed under the MIT license
On Board Accurate Calibration of Dual-Channel Radiometers Using Internal and External References
This paper presents a method for combining internal
noise injection and external reference standard looks to accurately
calibrate an airborne dual-channel radiometer. The method
allows real-time estimation of the correct values of the radiometer
gains and offsets, even for nontemperature-stabilized radiometers
and with minimum loss of measurement time spent in external
load measurement. Crosstalk and leakage introduced by the noise
injection circuitry is also taken into account, thus providing high
gain and offset estimation accuracy. The method was implemented
on a National Oceanic and Atmospheric Administration airborne
instrument, the Polarimetric Scanning Radiometer, which was
used to obtain an extensive set of radiometric measurements over
oceanic convection during CAMEX3 in August–September 1998
The BladeMistress Corpus: From Talk to Action in Virtual Worlds
htmlabstractVirtual Worlds (VW) are online environments where people come together to interact and perform various tasks. The chat transcripts of interactions in VWs pose unique opportunities and challenges for language analysis: Firstly, the language of the transcripts is very brief, informal, and task-oriented. Secondly, in addition to chat, a VW system records users’ in-world activities. Such a record could allow us to analyze how the language of interactions is linked to the users actions. For example, we can make the language analysis of the users dialogues more effective by taking into account the context of the corresponding action or we can predict or detect users actions by analyzing the content of conversations. Thirdly, a joined analysis of both the language and the actions would empower us to build effective modes of the users and their behavior. In this paper we present a corpus constructed from logs from an online multiplayer game
BladeMistress. We describe the original logs, annotations that we created on the data, and summarize some of the experiments
Observing Users - Designing clarity a case study on the user-centred design of a cross-language information retrieval system
This paper presents a case study of the development of an interface to a novel and complex form of document retrieval: searching for texts written in foreign languages based on native language queries. Although the underlying technology for achieving such a search is relatively well understood, the appropriate interface design is not. A study involving users (with such searching needs) from the start of the design process is described covering initial examination of user needs and tasks; preliminary
design and testing of interface components; building, testing, and further refining an interface; before
finally conducting usability tests of the system. Lessons are learned at every stage of the process leading to a much more informed view of how such an interface should be built
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