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Ashit Talukder's Web Page at the Jet Propulsion Laboratory/ Caltech  

Address:
Senior Research Scientist, Level A
JPL, 4800 Oak Grove Drive,
MS 300-123, Pasadena, CA 91109

Email: ashit.talukder@jpl.nasa.gov
Phone: 818 354 1000, Fax 818 393 3302

                  
Jet Propulsion LaboratoryCalifornia Institute of Technology


                                                          

 

I am a Senior Research Scientist  (Level A) at the Jet  Propulsion Laboratory/NASA, California Institute of Technology, located in  Pasadena, CA, USA. I also hold an appointment as an Associate Professor at the Univ. of Southern California (webpage is located here ). I have a PhD from the Dept.  of Electrical and Computer Engineering, Carnegie Mellon University where I  worked with Prof. David Casasent.  I obtained my M.S. at Iowa State University where I worked with Dr. Jennifer  Davidson . I am a principal investigator in several  projects funded by DARPA, NASA, Dept. of Homeland Security, U.S. Army, commercial organizations, and the NIH, in a  variety of areas spanning multidisciplinary areas in computer science and engineering, ranging from robotics, biometrics, intelligent sensor networks, sensor fusion, data mining, and system optimization and control to machine learning, computer vision, pattern recognition, and image  processing. I have directly supervised, and managed over 16 researchers comprised of research senior staff and post-docs at USC and JPL including recruiting and building the team, conducting administrative oversight, technical leadership, and providing vision and guidance to the entire team. 

I have more than 65 publications in journals and conference  proceedings. I have given 2 plenary lectures at international conferences and workshops, a colloquial lecture at the University of South Florida, several invited talks at conferences and academic institutions, and 3 Keynote Addresses at conferences. I am a member of the technical organizing committee of the Optical  Pattern Recognition Conference in the Annual SPIE Defense and Security Symposium  (formerly known as the Annual SPIE  AeroSense Conference), held in Orlando, FL every year during  April. I have chaired several conference sessions (including sessions on  Optical Pattern Recognition and " Active  vision in robotics " at Photonics East,  Intelligent Robotics and Computer Vision XVII), and am a reviewer on several  journals (IEEE Trans. Image Processing, IEEE Transactions on Signal Processing,  IEEE Transactions on Systems, Man, and Cybernetics-B, Applied Optics,  Neurocomputing, Neural Networks, and Optical Engineering).  My detailed research  accomplishments are listed in my CV (not up to date!!).                                                                                         .  


Research Interests and Activities

My interests are in the general broad area of Autonomous Systems, including:

Applications and fields I've worked in over the past several years include:

My PhD dissertation at Carnegie Mellon University entitled " Nonlinear Feature Extraction for Pattern Recognition Applications" involved the design of new machine learning techniques for nonlinear kernel-based feature extraction that I developed independently of support vector machines and kernel-PCA, and have shown to outperform SVMs and kernel PCA on highly nonlinear, high-dimensional data sets such as images and multi-dimensional data. You can download a copy of my PhD thesis here. If you need a PDF file, please email me at Ashit.Talukder@jpl.nasa.gov and I will gladly send you a PDF file of my thesis.

I've led and worked on several industrial and federal funded projects at JPL, USC, and CMU . A few of the relevant projects are listed below. While this list below is not comprehensive, it covers some of areas that I have worked on in the past.


 
Research and Commercial Projects

 

Biometrics and Surveillance Systems

We have built state of the art biometrics and surveillance systems for several federal sponsors. The system is a multimodal long-standoff biometrics system, that can detect human at a long standoff distance, identify them using the multimodal measurements. We have unique capability to detect a human behind a wall and also determine the identity of an individual through walls at a long distance (compared to existing solutions that can only detect the presence of a person behind walls).  Due to the sensitive nature of this work, the technical details of the biometrics and surveillance system cannot be provided online.

 

Wireless Intelligent Sensor Networks and Software Defined Radios with real-time Resource Allocation Capabilities

In this task, we have developed a wireless adaptive sensor network hardware testbed with nodes that run for days, developed distributed sensing algorithms using novel pattern recognition techniques and sensor fusion algorithms, and designed and implemented new control optimization and resource allocation algorithms for real-time distributed end-to-end system management. Our primary contributions are:

                                                     Wireless distributed sensor network architecture

    

    Levels 1 and 2                             Levels 1, 2,  and 3 in the sensor network

Event Visualization tools in sensor network

             Event visualization tools in Level 3 of our sensor network

Adaptive Control and Resource Management in Multiple Distributed Sensor Networks and Software Defined Radios 

We have designed and implemented novel control algorithms for real-time adaptive operation of multiple RF nodes in dynamic  environments where the channel noise and ambient RF noise characteristics can change dramatically based on the relative postion and motion between nodes. We use novel Model Predictive Control Algorithms on RF nodes with reasonable storage/memory resources, and Markov Decision Processes on RF nodes with extremely limited storage/limited resources (less than 4K of memory) for adaptive resource management and coordinated operation of the SDR nodes, where each node has different computing, momory and RF characteristics. We believe our work in this area to be the first demonstrable example of real-time adaptive control of distributed wireless nodes and software-programmable radios with such limited computing and storage resources .

 

Coordination of Unmanned Mobile Robots with Wireless Sensor Networks for Coastal Environmental Monitoring  

We developed a novel framework for controlling operational parameters of both fixed sensors and mobile unmanned robots  in real-time and using the resulting sensor observations to increase the predictive accuracy of pre-computed mathematical models of the ocean environment. The sensor controller uses the Model Predictive Control technique to focus limited sensor resources to the regions that are most likely to impact the accuracy of the model forecasts. The system was demonstrated on an offline simulation of the environment of the New York harbor and ocean. The sensor network adaptation and resource management concept for coastal monitoring networks are shown below.

Demonstration of adaptive control of 4 underwater unmanned vehicles (UUVs) (red and blue dots) in response 
to a flooding event (green regions) as it evolves over time

 

Cross-Media Streaming Data Mining for Cyclone Detection and Tracking Using Knowledge Transfer and Machine Learning  

Tropical and extra-tropical cyclones are important components of the Earth climate system that exhibit variability at different temporal and spatial scales. A cyclone landfall causes great devastation, incurs fatality, and affects people's livelihood. To identify and track tropical weather system, the Tropical Prediction Center/National Hurricane Center (TPC/NHC) uses conventional surface and upper-air observations and reconnaissance aircraft reports (Pasch, Stewart, and Brown 2003), and these are concentrated in the North American coasts and in Japan/Europe to some degree. Coverage on a global basis, especially in under-developed and developing nations such as large portions of Asia and Africa is limited or lacking which results in disastrous consequences in many of these regions. In recent years, some studies have used satellite images that are manually retrieved and analyzed to improve the accuracy of cyclone tracking; this procedure is currently slow, tedious, involves coverage of only local regions in North America, and requires close analysis by teams of experts.  

Mining of remote satellite data poses to be a truly challenging task, like most multimedia data mining problems. The datasets have different resolutions, varying dimensionality (1-D, 2-D or higher), and are often irregularly sampled (see examples below)

 

Our recent work (Ho and Talukder 2008b) showed the feasibility of using QuikSCAT remote satellite wind measurements for automated cyclone identification. In this approach, we have designed novel feature extraction mechanisms for cyclone segmentation and discovery from QuikSCAT wind measurements. A new ensemble classifier is used to robustly locate cyclones while rejecting false regions with characteristics similar to cyclonic regions. Our data preprocessing, feature extraction, segmentation, and machine elarning classification solution for cyclone discovery using single sensor QuikSCAT measurements is shown below.

 

However, QuikSCAT single sensor measurements have some drawbacks. Due to the polar orbiting nature of the QuikSCAT satellite, it has limited spatial and temporal coverage. In particular, the time interval between two consecutive observations of a cyclone is approximately around 12 hours. Sometimes the sensor can only capture partial measurement of the cyclone due to the orbiting path. To alleviate these problems, one can use sensor measurements from multiple orbiting satellites. However, sensors from other satellites measure other earth and atmospheric properties. These measurements are not as powerful in identifying cyclone as the wind properties measured by the Scatterometer on QuikSCAT satellite. For example, the precipitation rate measured by the Tropical Rain Measurement Mission (TRMM)[1] has been used to trace the cyclone track manually either during a cyclone event or as a reanalysis after a cyclone event. However, the precipitation rate cannot be used for cyclone identification since heavy rainfall does not imply a cyclone event. Moreover, since precipitation rate is not a definite cyclone indicator, there is no archive of positively labeled (cyclone) examples from the TRMM data by the scientific community. the main contribution is a methodology for transferring local spatial-temporal knowledge between satellite data from different data sources to enable event detection using weaker features. To avoid negative transfer for our methodology, the assumption that the weaker feature, which is not a definite discriminating feature, has to be able to pick up the event of interest must be satisfied. In other words, without applying our methodology, using the weaker feature for object detection/identification should result in a high false positive rate and high true positive rate, i.e. low precision but high recall. This methodology also significantly improves the temporal resolution for cyclones to 3 hr accuracies and resolves a large number of event occlusion instances that would occur in single sensor QuikSCAT-based cyclone tracking.

Concept for Knowledge transfer learning between multiple satellites for more accurate cyclone detection & tracking

 

Autonomous cyclone detection and tracking for Hurricane Gonu in the Arabian Sea in 2005 using knowledge sharing 
between QuikSCAT and TRMM. Red square is the final detected cyclone - Green and black squares correspond to rejected false alarms.


Mobile Continuous Adaptive Decision Making and Learning for Autonomous Sensor Networks

We have implemented novel pattern recognition algorithms for real-time continuous adaptive monitoring of dynamic environments from distributed heterogeneous RF nodes and sensors, and demonstrated this on real-time mobile telehealth monitoring. While several publications exist on this work in a variety of technical conferences and workshops, the most relevant media coverage of the applicability of our system in a real-world domain can be found in the CrossBow 2005 Second Quarter Industrial Newsletter at  http://www.xbow.com/General_info/Info_pdf_files/XbowNewsletter_Q2-05.pdf

Dynamic Scene Perception from Mobile Robots in Urban Environments

I am a Co-Investigator in competed & funded DARPA IPTO Robotics 2020 contract Object-Referenced Robot Navigation in Dynamic Urban Environments (Total Award: $4.0 million). Collaborating institutions: JPL, Carnegie Mellon University, SRI, UC Santa Cruz. Start date: Sept. 2002 : End: Sept 2004. Project involves detection of moving objects in real-time from mobile robot platforms using vision sensors, and localization of robots in urban terrain using high-level percept referenced navigation commands specified by user.

Robot Navigation and Control in Natural Terrain

DARPA funded MARS (Mobile Autonomous Robot Software) project involving design of algorithms to be used for autonomous vehicles and robots for use in urban environments and natural terrain. Tasks include autonomous terrain classification and obstacle detection using 3-D modeling and vision, computer graphics, geometrical reasoning, and pattern recognition. Details of our ongoing DARPA MARS work at JPL can be found here. My work also ties in with the DARPA ATO Tactical Mobile Robotics (TMR) program at JPL that involves the JPL Urban Robot (URBIE), DARPA PERCEPTOR., and DEMO III.

Face Detection and Facial Feature Extraction

Face detection and facial feature location funded by NGMTec and Graphco Technologies for synthetic generation of video based on audio input for use in low-bandwidth videoconferencing, and speech-to-video applications

Biomedical Applications

Automatic Target Recognition, Industrial Automation and Robotics


 Selected Publications


PATENTS AND HONORS


Ashit's Resume (CV)

 

If you have any questions, or want to contact me, please send me email at: Ashit.Talukder@jpl.nasa.gov


 
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