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Full-Text Articles in Computer Engineering

New Frontiers In Ocean Exploration: The 2011 E/V Nautilus Field Season, K. Bell, R. Ballard, D. Coleman, C. Roman, M. Brennan, T. Turanli, M. Duman, S. Carey, P. Nomikou, M. Marani, M. Rosi, J. Austin, M. Canals, J. Karson, L. Mayer, Y. Makovsky Dec 2011

New Frontiers In Ocean Exploration: The 2011 E/V Nautilus Field Season, K. Bell, R. Ballard, D. Coleman, C. Roman, M. Brennan, T. Turanli, M. Duman, S. Carey, P. Nomikou, M. Marani, M. Rosi, J. Austin, M. Canals, J. Karson, L. Mayer, Y. Makovsky

Christopher N. Roman

In the summer of 2011, the Exploration Vessel NAUTILUS is undertaking a four-month expedition to the Black, Aegean and Mediterranean Seas, and North Atlantic Ocean. The primary goal of the NAUTILUS is to create a focus of international leadership for the development and integration of leading-edge technologies, educational programs, field operations, and public outreach programs for ocean exploration, in partnership with NOAA, National Geographic Society, Office of Naval Research, and other sponsors. To do so, the program uses a complement of deep submergence vehicle systems and “telepresence” technologies to engage scientists, educators and the public, both at sea and ashore, …


High Resolution Sea Floor Bathymetry Using High Frequency Multibeam Sonar And Structured Light Laser Imaging, C. Roman, G. Inglis, C. Smart, I. Vaughn, S. Carey Dec 2011

High Resolution Sea Floor Bathymetry Using High Frequency Multibeam Sonar And Structured Light Laser Imaging, C. Roman, G. Inglis, C. Smart, I. Vaughn, S. Carey

Christopher N. Roman

Detailed bathymetric maps of the sea floor with centimeter level resolution can be produced by underwater vehicles using multibeam sonars and structured light laser imaging. Over spatial scales up to tens of thousands of square meters it is possible to produce maps gridded to sub centimeter levels. This level of accuracy demands detailed treatments of the sensor relative data, the vehicle navigation data and the vehicle to sensor position and rotational offsets. The presented results will show comparisons between these two sensor modalities. Data have a been collected during recent field programs to the Kolumbo volcanic crater and the Southern …


Remote Analysis Of Grain Size Characteristic In Submarine Pyroclastic Deposits From Kolumbo Volcano, Greece, C. Smart, D. P. Whitesell, C. Roman, S. Carey Dec 2011

Remote Analysis Of Grain Size Characteristic In Submarine Pyroclastic Deposits From Kolumbo Volcano, Greece, C. Smart, D. P. Whitesell, C. Roman, S. Carey

Christopher N. Roman

Grain size characteristics of pyroclastic deposits provide valuable information about source eruption energetics and depositional processes. Maximum size and sorting are often used to discriminate between fallout and sediment gravity flow processes during explosive eruptions. In the submarine environment the collection of such data in thick pyroclastic sequences is extremely challenging and potentially time consuming. A method has been developed to extract grain size information from stereo images collected by a remotely operated vehicle (ROV). In the summer of 2010 the ROV Hercules collected a suite of stereo images from a thick pumice sequence in the caldera walls of Kolumbo …


Detection Of Diffuse Sea Floor Venting Using Structured Light Imaging, G. Inglis, C. Smart, C. Roman, S. Carey Dec 2011

Detection Of Diffuse Sea Floor Venting Using Structured Light Imaging, G. Inglis, C. Smart, C. Roman, S. Carey

Christopher N. Roman

Efficiently identifying and localizing diffuse sea floor venting at hydrothermal and cold seep sites is often difficult. Actively venting fluids are usually identified by a temperature induced optical shimmering seen during direct visual inspections or in video data collected by vehicles working close to the sea floor. Relying on such direct methods complicates establishing spatial relations between areas within a survey covering a broad area. Our recent work with a structured light laser system has shown that venting can also be detected in the image data in an automated fashion. A structured light laser system consists of a camera and …


Development Of High Resolution Sea Floor Mapping Tools And Techniques, Gabrielle Inglis, Ian Vaughn, Clara Smart, Chris Roman Apr 2011

Development Of High Resolution Sea Floor Mapping Tools And Techniques, Gabrielle Inglis, Ian Vaughn, Clara Smart, Chris Roman

Christopher N. Roman

There is a persistent need for high resolution photographic and bathymetric maps of the sea floor for many research areas in marine geology, biology and archaeology. This poster will present recent work using high frequency multibeam sonars, stereo vision and structured light laser imaging techniques to create maps with centimeter resolution for these applications. This research involves the development of new image and sonar processing techniques that combat the typical difficulties of imperfect navigation information, limited sensor ranges and adverse environmental conditions associated with using marine robotic vehicles in the ocean. Data for this work has been collected with the …


Imirok: Real-Time Imitative Robotic Arm Control For Home Robot Applications, Heng-Tze Cheng, Zheng Sun, Pei Zhang Mar 2011

Imirok: Real-Time Imitative Robotic Arm Control For Home Robot Applications, Heng-Tze Cheng, Zheng Sun, Pei Zhang

Zheng Sun

Training home robots to behave like human can help people with their daily chores and repetitive tasks. In this paper, we present Imirok, a system to remotely control robotic arms by user motion using low-cost, off-the-shelf mobile devices and webcam. The motion tracking algorithm detects user motion in real-time, without classifier training or predefined action set. Experimental results show that the system achieves 90% precision and recall rate on motion detection with blank background, and is robust under the change of cluttered background and user-to-camera distance.


Leveraging Mobile Context For Effective Collaboration And Task Management In Disaster Response, Faisal Luqman, Martin L. Griss Mar 2011

Leveraging Mobile Context For Effective Collaboration And Task Management In Disaster Response, Faisal Luqman, Martin L. Griss

Martin L Griss

Collaboration and task management is challenging in distributed, dynamically-formed teams, typical in large scale disaster response scenarios. Ineffective collaboration may result in poor performance and possible loss of life. In this paper, we present Overseer, an agent-based system that exploits context information from mobile devices to facilitate collaboration and task allocation. We describe our system architecture and show how mobile context can be used to create dynamic role-based assignments to support collaboration and effective task management.


Anubis: An Attestation Protocol For Distributed Context-Aware Applications, Senaka Buthpitiya, Feng-Tso Sun, Heng-Tze Chen, Patrick Tague, Martin L. Griss, Anind K. Dey Jan 2011

Anubis: An Attestation Protocol For Distributed Context-Aware Applications, Senaka Buthpitiya, Feng-Tso Sun, Heng-Tze Chen, Patrick Tague, Martin L. Griss, Anind K. Dey

Martin L Griss

Sharing sensitive context information among multiple distributed components in mobile environments introduces major security concerns. The distributed sensing, processing and actuating components of these applications can be compromised and modified or impersonated to extract private and confidential information or to inject false information. In this paper we present the Anubis protocol for remote code attestation and access control of distributed components using remote execution of trusted code. Our Anubis protocol leverages previous work in the fields of wireless sensor networks and secure web browsing. Anubis allows new components to be introduced to the environment without updating existing components. Our implementation …


Mobile Context-Aware Personal Messaging Assistant, Senaka Buthpitiya, Deepthi Madamanchi, Sumalatha Kommaraju, Martin L. Griss Jan 2011

Mobile Context-Aware Personal Messaging Assistant, Senaka Buthpitiya, Deepthi Madamanchi, Sumalatha Kommaraju, Martin L. Griss

Martin L Griss

A previous study shows that busy professionals receive in excess of 50 emails per day of which approximately 23% require immediate attention, 13% require attention later and 64% are unimportant and typically ignored. The flood of emails impact mobile users even more heavily. Flooded inboxes cause busy professionals to spend considerable amounts of time searching for important messages, and there has been much research into automating the process using email content for classification; but we find email priority depends also on user context. In this paper we describe the Personal Messaging Assistant (PMA), an advanced rule-based email management system which …


Sensorchestra: Collaborative Sensing For Symbolic Location Recognition, Heng-Tze Cheng, Feng-Tso Sun, Senaka Buthpitiya, Martin L. Griss Jan 2011

Sensorchestra: Collaborative Sensing For Symbolic Location Recognition, Heng-Tze Cheng, Feng-Tso Sun, Senaka Buthpitiya, Martin L. Griss

Martin L Griss

"Symbolic location of a user, like a store name in a mall, is essential for context-based mobile advertising. Existing fingerprint- based localization using only a single phone is susceptible to noise, and has a major limitation in that the phone has to be held in the hand at all times. In this paper, we present SensOrchestra, a col- laborative sensing framework for symbolic location recognition that groups nearby phones to recognize ambient sounds and images of a location collaboratively. We investigated audio and image features, and designed a classifier fusion model to integrate estimates from diff erent phones. We also …


Activity-Aware Mental Stress Detection Using Physiological Sensors, Feng-Tso Sun, Cynthia Kuo, Heng-Tze Cheng, Senaka Buthpitiya, Patricia Collins, Martin Griss Jan 2011

Activity-Aware Mental Stress Detection Using Physiological Sensors, Feng-Tso Sun, Cynthia Kuo, Heng-Tze Cheng, Senaka Buthpitiya, Patricia Collins, Martin Griss

Martin L Griss

"Continuous stress monitoring may help users better understand their stress patterns and provide physicians with more reliable data for interventions. Previously, studies on mental stress detection were limited to a laboratory environment where participants generally rested in a sedentary position. However, it is impractical to exclude the effects of physical activity while developing a pervasive stress monitoring application for everyday use. The physiological responses caused by mental stress can be masked by variations due to physical activity. We present an activity-aware mental stress detection scheme. Electrocardiogram (ECG), galvanic skin response (GSR), and accelerometer data were gathered from 20 participants across …


Omnisense: A Collaborative Sensing Framework For User Context Recognition Using Mobile Phones, Heng-Tze Cheng, Senaka Buthpitiya, Feng-Tso Sun, Martin L. Griss Jan 2011

Omnisense: A Collaborative Sensing Framework For User Context Recognition Using Mobile Phones, Heng-Tze Cheng, Senaka Buthpitiya, Feng-Tso Sun, Martin L. Griss

Martin L Griss

Context information, including a user’s locations and activities, is indispensable for context-aware applications such as targeted advertising and disaster response. Inferring user context from sensor data is intrinsically challenging due to the semantic gap between low-level signals and high-level human activities. When implemented on mobile phones, more challenges on resource limitations are present. While most existing work focuses on context recognition using a single mobile phone, collaboration among multiple phones has received little attention, and the recognition accuracy is susceptible to phone position and ambient changes. Simply putting a phone in one’s pocket can render the microphone muffled and the …


Room-Level Wi-Fi Location Tracking, Joshua Correa, Ed Katz, Patricia Collins, Martin Griss Jan 2011

Room-Level Wi-Fi Location Tracking, Joshua Correa, Ed Katz, Patricia Collins, Martin Griss

Martin L Griss

Context-aware applications for indoor intelligent environments require an appropriately accurate and stable interior positioning system to adapt services to the location of a mobile user or mobile device in a building. Different technologies provide a varying mix of resolution, accuracy, stability and challenges. In this paper we report on our experience using an existing Wi-Fi infrastructure without specialized hardware added to support location tracking. There are several approaches to track the location of Wi-Fi enabled devices within a building such as signal propagation models and signature matching. We found signature matching most effective in our environment. Signature matching is accomplished …


Adaptive Discrete-Time Controller Design With Neural Network For Hypersonic Flight Vehicle Via Back-Stepping, Bin Xu Jan 2011

Adaptive Discrete-Time Controller Design With Neural Network For Hypersonic Flight Vehicle Via Back-Stepping, Bin Xu

Bin Xu

In this article, the adaptive neural controller in discrete time is investigated for the longitudinal dynamics of a generic hypersonic flight vehicle. The dynamics are decomposed into the altitude subsystem and the velocity subsystem. The altitude subsystem is transformed into the strict-feedback form from which the discrete-time model is derived by the first-order Taylor expansion. The virtual control is designed with nominal feedback and neural network (NN) approximation via back-stepping. Meanwhile, one adaptive NN controller is designed for the velocity subsystem. To avoid the circular construction problem in the practical control, the design of coefficients adopts the upper bound instead …


Adaptive Neural Control Based On Hgo For Hypersonic Flight Vehicles, Bin Xu Jan 2011

Adaptive Neural Control Based On Hgo For Hypersonic Flight Vehicles, Bin Xu

Bin Xu

This paper describes the design of adaptive neural controller for the longitudinal dynamics of a generic hypersonic flight vehicle (HFV) which are decomposed into two functional systems, namely the altitude subsystem and the velocity subsystem. For each subsystem, one adaptive neural controller is investigated based on the normal output-feedback formulation. For the altitude subsystem, the high gain observer (HGO) is taken to estimate the unknown newly defined states. Only one neural network (NN) is employed to approximate the lumped uncertain system nonlinearity during the controller design which is considerably simpler than the ones based on back-stepping scheme with the strict-feedback …


Task Allocation For Multi-Spacecraft Cooperation Based On Estimation Of Distribution Algorithm, Bin Xu Jan 2011

Task Allocation For Multi-Spacecraft Cooperation Based On Estimation Of Distribution Algorithm, Bin Xu

Bin Xu

One two-stage task allocation strategy is proposed for multi-spacecraft cooperation during the long-range orbit transfer with two impulses. This paper focuses on the task value maximum and cost minimum optimization by assigning spacecraft to different task. At the first stage time and energy cost are considered based on the spacecraft dynamics. The optimization result is together with the target value as the factor for the task allocation model at the second stage. The optimization is processed separately in continuous and discrete time domain with estimation of distribution algorithm (EDA). Different task allocation mode is formulated and the strategy is verified …


Composite Control Based On Optimal Torque Control And Adaptive Kriging Control For The Crab Rover, Bin Xu Jan 2011

Composite Control Based On Optimal Torque Control And Adaptive Kriging Control For The Crab Rover, Bin Xu

Bin Xu

Terrainability is mostly dependant on the suspension mechanism and the control of a space rover. For the six wheeled CRAB rover, this paper presents the composite control design with torque control and adaptive Kriging control to improve the terrainability, somewhat related to minimizing heel slip. As CRAB is moving slowly, the torque control is processed by minimizing the variance of the required friction coefficient based on the static model. Adaptive Kriging control is used to track the commanded velocity. The system uncertainty is compensated by Kriging estimation based on the velocity dynamics. Experiment results with two different tires show the …


Adaptive Hypersonic Flight Control Via Back-Stepping And Kriging Estimation, Bin Xu Jan 2011

Adaptive Hypersonic Flight Control Via Back-Stepping And Kriging Estimation, Bin Xu

Bin Xu

This paper investigates the adaptive Kriging controller for the longitudinal dynamics of a generic hypersonic flight vehicle (HFV). For the altitude subsystem, the dynamics are transformed into the strict-feedback form where the backstepping scheme is employed. Considering the nonlinearity of the dynamics, the nominal feedback is included in the controller while Kriging system is designed to estimate the uncertainty. With the proposed controller, the almost surely bounded stability is guaranteed. The simulation study is presented to show the effectiveness of the proposed control approach.