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Computer Engineering Commons

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2007

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Articles 481 - 510 of 556

Full-Text Articles in Computer Engineering

Delay-Insensitive Ternary Logic (Ditl), Ravi Sankar Parameswaran Nair Jan 2007

Delay-Insensitive Ternary Logic (Ditl), Ravi Sankar Parameswaran Nair

Masters Theses

"This thesis focuses on development of a Single Rail Ternary Voltage Delay-Insensitive paradigm called Delay-Insensitive Ternary Logic (DITL), which is based on NULL Convention Logic (NCL). Single rail asynchronous logic has potential advantages over Dual-Rail logic such as reduction of Power and Interconnect as well as Logic Area. The DITL concept is developed in steps of individual circuit components. These components are designed at the transistor level and are connected together to form a registered pipeline system. Some variations in pipeline design are also investigated"--Abstract, page iii.


A Simulation Environment Modeling The Use Of Wireless Sensor Networks For The Detection And Mapping Of Wildfires, Matthew Gann Jan 2007

A Simulation Environment Modeling The Use Of Wireless Sensor Networks For The Detection And Mapping Of Wildfires, Matthew Gann

Masters Theses

"Over the past 5 years, billions of dollars have been spent fighting wildfires which consume thousands of acres. Currently, satellites are the primary source of information regarding the location of large scale wildfires. The satellites in use are capable of reporting the location of the wildfire, but these reports are generated infrequently and have a low spatial resolution, where the reported location of the fire can be off by 500 meters. Timely detection (latency) and frequent report (throughput) are needed to help prevent the destruction caused by wildfires. This thesis, a system is described based on an ad-hoc wireless sensor …


Printed Circuit Board (Pcb) Loss Characterization Up-To 20 Ghz And Modeling, Analysis And Validation, Abhilash Rajagopal Jan 2007

Printed Circuit Board (Pcb) Loss Characterization Up-To 20 Ghz And Modeling, Analysis And Validation, Abhilash Rajagopal

Masters Theses

"Dielectric properties and losses are increasingly more important in signal link path characterization, as data rates increases. High-frequency effects such as dielectric losses, dispersion and skin-effect losses need to be considered. For ensuring signal integrity, it is important to characterize losses of printed circuit board (PCB) dielectrics. To extract dielectric properties of a stripline transmission medium, an analytical technique was used...Two test materials were studied, and the extraction procedure was refined. This technique was applied to microstrip transmission lines. Two analytical solutions were derived for extracting practical material parameters. A microstrip test vehicle was designed and the two extraction methods …


Energy Efficient Processor Operation And Vibration Based Energy Harvesting Schemes For Wireless Sensor Nodes, Phani Kumar Gajjala Jan 2007

Energy Efficient Processor Operation And Vibration Based Energy Harvesting Schemes For Wireless Sensor Nodes, Phani Kumar Gajjala

Masters Theses

"A wireless Sensor Network (WSN) is a network of spatially distributed autonomous sensors deployed in the environment in order to cooperatively monitor physical or environmental conditions such as temperature, sound, pressure, motion or pollutants at different locations. Each node in a sensor network is equipped with a radio transceiver, a microprocessor and an energy source such as a battery which should be replaced periodically. To increase the lifetime of the network keeping the small size in mind, methods should be put in place to reduce the power consumption of the sensor node or increase the node life and/or to supply …


A Network Infrastructure For Real-Time Monitoring Of Campus Energy Consumption, Sandeep Kunchum Jan 2007

A Network Infrastructure For Real-Time Monitoring Of Campus Energy Consumption, Sandeep Kunchum

Masters Theses

"Pressing environmental concerns and rising energy costs have led many organizations to carefully review their energy consumption. Conservation requires that energy use be monitored accurately and continuously, to identify areas with higher energy consumption. Lighting has repeatedly been identified as such an area. A simple, yet effective method for reducing lighting energy consumption is retrofitting existing light fixtures with modern energy-efficient versions. The University of Missouri-Rolla is currently carrying out a lighting retrofit of all fixtures on campus. The pilot building for this project is McNutt Hall, as it has the single highest consumption of lighting energy. The results of …


Identification Of Radial Streaming And Pseudopods In Dermoscopy Images, Sayali Prabhakar Deshpande Jan 2007

Identification Of Radial Streaming And Pseudopods In Dermoscopy Images, Sayali Prabhakar Deshpande

Masters Theses

"This thesis demonstrates an algorithm to identify the features of radial streaming and pseudopods found in dermoscopy images of malignant melanoma. The algorithm includes preprocessing images using the Principal Component Transform and an application of mathematical techniques to extract the desired features from the lesion image on the basis of color, size, shape, and orientation with respect to the lesion boundary. These identified features are further used to classify the lesion as malignant or benign. The proposed algorithm has produced a diagnostic accuracy of 90.50% for the training set of 31 malignant and 109 benign images and a diagnostic accuracy …


Design For Test Techniques For Asynchronous Ncl Designs And Fpgas, Sindhu Kakarla Jan 2007

Design For Test Techniques For Asynchronous Ncl Designs And Fpgas, Sindhu Kakarla

Masters Theses

"Testing of an electronic chip is an important step in the design process, as it can detect faults and ensure reliability. Design for Test (DFT) methods are used to modify existing designs to enable their testing by Automatic Test Pattern Generators. This thesis focuses on developing testing techniques for design automation of NULL Conventional Logic (NCL) circuits and for detection of capacitive crosstalk effects in Field Programmable Gate Arrays (FPGAs).

A novel technique is developed for testing asynchronous NCL designs aimed at good fault coverage with acceptable gate overhead. The technique focuses on testing stuck-at-faults in the internal feedback paths …


Dit Frequency Based Incremental Attribute Selection For Gre., John D. Kelleher Jan 2007

Dit Frequency Based Incremental Attribute Selection For Gre., John D. Kelleher

Conference papers

The DIT system uses an incremental greedy search to generate descriptions, (similar to the incremental algorithm described in (Dale and Reiter, 1995) ) incremental algorithm). The selection of the next attribute to be tested for inclusion in the description is ordered by the absolute frequency of each attribute in the training corpus. Attributes are selected in descending order of frequency (i.e. the attribute that occurred most frequently in the training corpus is selected first).


Investigating Text Message Classification Using Case-Based Reasoning, Matt Healy Jan 2007

Investigating Text Message Classification Using Case-Based Reasoning, Matt Healy

Masters

Text classification is the categorization of text into a predefined set of categories. Text classification is becoming increasingly important given the large volume of text stored electronically e.g. email, digital libraries and the World Wide Web (WWW). These documents represent a massive amount of information that can be accessed easily. To gain benefit from using this information requires organisation. One way of organising it automatically is to use text classification. A number of well known machine learning techniques have been used in text classification including Naïve Bayes, Support Vector Machines and Decision Trees, and the less commonly used are k-Nearest …


Mediating Between Qualitative And Quantitative Representations For Task-Orientated Human-Robot Interaction., Michael Brenner, John D. Kelleher, Nick Hawes, Jeremy Wyatt Jan 2007

Mediating Between Qualitative And Quantitative Representations For Task-Orientated Human-Robot Interaction., Michael Brenner, John D. Kelleher, Nick Hawes, Jeremy Wyatt

Conference papers

In human-robot interaction (HRI) it is essential that the robot interprets and reacts to a human’s utterances in a manner that reflects their intended meaning. In this paper we present a collection of novel techniques that allow a robot to interpret and execute spoken commands describing manipulation goals involving qualitative spatial constraints (e.g. “put the red ball near the blue cube”). The resulting implemented system integrates computer vision, potential field models of spatial relationships, and action planning to mediate between the continuous real world, and discrete, qualitative representations used for symbolic reasoning.


On Optimal Survivability Design In Wdm Optical Networks Under Scheduled Traffic Models, Tianjian Li Jan 2007

On Optimal Survivability Design In Wdm Optical Networks Under Scheduled Traffic Models, Tianjian Li

Browse all Theses and Dissertations

Wavelength division multiplexing (WDM) optical networks are widely viewed as the most appropriate choice for future Internet backbone with the potential to fulfill the ever-growing demands for bandwidth. WDM divides the enormous bandwidth of an optical fiber into many non-overlapping wavelength channels, each of which may operate at the rate of 10 Gigabit per second or higher. A failure in a network such as a cable cut may result in a tremendous loss of data. Therefore, survivability is a very important issue in WDM optical networks. The objective of this dissertation is to address the survivability provisioning problem in WDM …


Implementation For A Coherent Keyword-Based Xml Query Language, Venkatakalyan Potturi Jan 2007

Implementation For A Coherent Keyword-Based Xml Query Language, Venkatakalyan Potturi

Browse all Theses and Dissertations

Due to the increasing pervasiveness of data sets using the XML data format, numerous query languages have been proposed that exploit the structure inherent in XML. Many such query languages, supported by specialized XML search engines, are complex and not suitable for naive users. A simple keyword based query language is described which not only exploits the structure of XML documents to extract relevant fragments, but can also fall back on retrieval through plain text search. This thesis focuses on developing a prototype implementation for a Coherent Keyword Based XML Query Language. It analyzes the typical challenges posed by the …


An Evolutionary Programming Algorithm For Automatic Chromatogram Alignment, Bonnie Jo Schwartz Jan 2007

An Evolutionary Programming Algorithm For Automatic Chromatogram Alignment, Bonnie Jo Schwartz

Browse all Theses and Dissertations

Scientists use liquid chromatography/mass spectrometry (LC/MS) instruments to measure metabolic responses to external stimuli. The data from these instruments can be distorted due to changes in the testing environment. Automating the removal of distortions is crucial in processing the data. The purpose of this thesis is to develop an algorithm that will automate the process.

The data produced by the LC/MS instrument were treated as images and image registration techniques were applied. A polynomial transformation function was assumed. An evolutionary programming algorithm was used to determine the coefficients of the polynomial. The data was manipulated to determine the best registration …


Role-Based Access Control For The Open Grid Services Architecture - Data Access And Integration (Ogsa-Dai), Anil L. Pereira Jan 2007

Role-Based Access Control For The Open Grid Services Architecture - Data Access And Integration (Ogsa-Dai), Anil L. Pereira

Browse all Theses and Dissertations

Grid has emerged recently as an integration infrastructure for the sharing and coordinated use of diverse resources in dynamic, distributed virtual organizations (VOs). A Data Grid is an architecture for the access, exchange, and sharing of data in the Grid environment. In this dissertation, role-based access control (RBAC) systems for heterogeneous data resources in Data Grid systems are proposed. The Open Grid Services Architecture - Data Access and Integration (OGSA-DAI) is a widely used framework for the integration of heterogeneous data resources in Grid systems.

However, in the OGSA-DAI system, access control causes substantial administration overhead for resource providers in …


Data Mining And Analysis On Multiple Time Series Object Data, Chunyu Jiang Jan 2007

Data Mining And Analysis On Multiple Time Series Object Data, Chunyu Jiang

Browse all Theses and Dissertations

Huge amount of data is available in our society and the need for turning such data into useful information and knowledge is urgent. Data mining is an important field addressing that need and significant progress has been achieved in the last decade. In several important application areas, data arises in the format of Multiple Time Series Object (MTSO) data, where each data object is an array of time series over a large set of features and each has an associated class or state. Very little research has been conducted towards this kind of data. Examples include computational toxicology, where each …


Xml Integrated Environment For Service-Oriented Data Management, Marwan Younes Maarouf Jan 2007

Xml Integrated Environment For Service-Oriented Data Management, Marwan Younes Maarouf

Browse all Theses and Dissertations

The proliferation of XML as a family of related standards including a markup language (XML), formatting semantics (XSL style sheets), a linking syntax (XLINK), and appropriate data schema standards have emerged as a de facto standard for encoding and sharing data between various applications. XML is designed to be simple, easily parsed and self-describing. XML is based on and support the idea of separation of concerns: information content is separated from information rendering, and relationships between data elements are provided via simple nesting and references. As the XML content grows, the ability to handle schemaless XML documents becomes more critical …


High Performance Text Document Clustering, Yanjun Li Jan 2007

High Performance Text Document Clustering, Yanjun Li

Browse all Theses and Dissertations

Data mining, also known as knowledge discovery in database (KDD), is the process to discover interesting unknown knowledge from a large amount of data. Text mining is to apply data mining techniques to extract interesting and nontrivial information and knowledge from unstructured text. Text clustering is one of important techniques of text mining, which is the unsupervised classification of similar documents into different groups.

This research focuses on improving the performance of text clustering. We investigated the text clustering algorithms in four aspects: document representation, documents closeness measurement, high dimension reduction and parallelization. We propose a group of high performance …


An Analysis Of Neutral Drift's Effect On The Evolution Of A Ctrnn Locomotion Controller With Noisy Fitness Evaluation, Gregory Robert Kramer Jan 2007

An Analysis Of Neutral Drift's Effect On The Evolution Of A Ctrnn Locomotion Controller With Noisy Fitness Evaluation, Gregory Robert Kramer

Browse all Theses and Dissertations

This dissertation focuses on the evolution of Continuous Time Recurrent Neural Networks (CTRNNs) as controllers for control systems. Existing research suggests that the process of neutral drift can greatly benefit evolution for problems whose fitness landscapes contain large-scale neutral networks. CTRNNs are known to be highly degenerate, providing a possible source of large-scale landscape neutrality, and existing research suggests that neutral drift benefits the evolution of simple CTRNNs. However, there has been no in-depth examination of the effects of neutral drift on complex CTRNN controllers, especially in the presence of noisy fitness evaluation. To address this problem, this dissertation presents …


Computational Methods For The Objective Review Of Forensic Dna Testing Results, Jason R. Gilder Jan 2007

Computational Methods For The Objective Review Of Forensic Dna Testing Results, Jason R. Gilder

Browse all Theses and Dissertations

Since the advent of criminal investigations, investigators have sought a "gold standard" for the evaluation of forensic evidence. Currently, deoxyribonucleic acid (DNA) technology is the most reliable method of identification. Short Tandem Repeat (STR) DNA genotyping has the potential for impressive match statistics, but the methodology not infallible. The condition of an evidentiary sample and potential issues with the handling and testing of a sample can lead to significant issues with the interpretation of DNA testing results. Forensic DNA interpretation standards are determined by laboratory validation studies that often involve small sample sizes. This dissertation presents novel methodologies to address …


Summaritive Digest For Large Document Repositories With Application To E-Rulemaking, Lijun Chen Jan 2007

Summaritive Digest For Large Document Repositories With Application To E-Rulemaking, Lijun Chen

Browse all Theses and Dissertations

Large document repositories need to be organized and summarized to make them more accessible and understandable. Such needs exist in many applications, including web search, e-rulemaking (electronic rulemaking) and document archiving. Even though much has been done in the areas of document clustering and summarization, there are still many new challenges and issues that need to be addressed as the repositories become larger, more prevalent and dynamic. In this dissertation, we investigate more informative ways to organize and summarize large document repositories, especially e-rulemaking feedback repositories (ERFRs), so that the large repositories can be managed and digested more efficiently and …


Comparative Microarray Data Mining, Shihong Mao Jan 2007

Comparative Microarray Data Mining, Shihong Mao

Browse all Theses and Dissertations

As a revolutionary technology, microarrays have great potential to provide genome-wide patterns of gene expression, to make accurate medical diagnosis, and to explore genetic causes underlying diseases. It is commonly believed that suitable analysis of microarray datasets can lead to achieve the above goals. While much has been done in microarray data mining, few previous studies, if any, focused on multiple datasets at the comparative level. This dissertation aims to fill this gap by developing tools and methods for set-based comparative microarray data mining. Specifically, we mine highly differentiative gene groups (HDGGs) from given datasets/classes, evaluate the concordance of datasets …


A Hybrid Approach To Retrieving Web Documents And Semantic Web Data, Trivikram Immaneni Jan 2007

A Hybrid Approach To Retrieving Web Documents And Semantic Web Data, Trivikram Immaneni

Browse all Theses and Dissertations

The Semantic Web has been evolving into a property-linked web of RDF data, conceptually divorced from (but physically housed in) the World Wide Web of hyperlinked documents. Data Retrieval techniques are typically used to retrieve data from the Semantic Web while Information Retrieval techniques are used to retrieve documents from the Hypertext Web. Conceptually unifying the two webs enables the exploitation of their interconnections resulting in benefits to both data and document retrieval. Towards this end, we present the Unified Web model that integrates the two webs and formalizes the structure and the semantics of their interconnections. We present a …


Bibliography Tools In The Context Of Www And Latex, Munushree Thummala Jan 2007

Bibliography Tools In The Context Of Www And Latex, Munushree Thummala

Browse all Theses and Dissertations

Preparation of academic papers involves not only the creative processes but also the more mechanical tasks such as adjusting the form and style to suit the demands of the publishing journal or conference. Among several packages that help in these rather tedious mechanical tasks, the TEX + LATEX + BibTEX combination is extremely popular. This thesis is about tools that help in the necessary task of citing related work accurately. It focuses on three aspects of this larger bibliography frame work: (i) a survey of existing bibliography formats and tools, (ii) a database view of BibTEX files and functionality that …


C-Fos As A Proapoptotic Agent In Trail-Induced Apoptosis In Prostate Cancer Cells, Xiaoping Zhang, Liang Zhang, Hongmei Yang, Xu Huang, Hasan H. Otu, Towia A. Libermann, William C. Dewolf, Roya Khosravi-Far, Aria F. Olumi Jan 2007

C-Fos As A Proapoptotic Agent In Trail-Induced Apoptosis In Prostate Cancer Cells, Xiaoping Zhang, Liang Zhang, Hongmei Yang, Xu Huang, Hasan H. Otu, Towia A. Libermann, William C. Dewolf, Roya Khosravi-Far, Aria F. Olumi

Department of Electrical and Computer Engineering: Faculty Publications

Tumor necrosis factor–related apoptosis-inducing ligand (TRAIL)/Apo-2L promotes apoptosis in cancer cells while sparing normal cells. Although many cancers are sensitive to TRAIL-induced apoptosis, some evade the proapoptotic effects of TRAIL. Therefore, differentiating molecular mechanisms that distinguish between TRAIL-sensitive and TRAIL-resistant tumors are essential for effective cancer therapies. Here, we show that c-Fos functions as a proapoptotic agent by repressing the antiapoptotic molecule c-FLIP(L). c-Fos binds the c-FLIP(L) promoter, represses its transcriptional activity, and reduces c-FLIP(L) mRNA and protein levels. Therefore, c-Fos is a key regulator of c-FLIP(L), and activation of c-Fos determines whether a cancer cell will undergo cell death …


Serum Proteome Profiling Detects Myelodysplastic Syndromes And Identifies Cxc Chemokine Ligands 4 And 7 As Markers For Advanced Disease, Manuel Aivado, Dimitrios Spentzos, Ulrich Germing, Gil Alterovitz, Xiao-Ying Meng, Franck Grall, Aristoteles A. N. Giagounidis, Giannoula Klement, Ulrich Steidl, Hasan H. Otu, Akos Czibere, Wolf C. Prall, Christof Iking-Konert, Michelle Shayne, Marco F. Ramoni, Norbert Gattermann, Rainer Haas, Constantine S. Mitsiades, Eric T. Fung, Towia A. Libermann Jan 2007

Serum Proteome Profiling Detects Myelodysplastic Syndromes And Identifies Cxc Chemokine Ligands 4 And 7 As Markers For Advanced Disease, Manuel Aivado, Dimitrios Spentzos, Ulrich Germing, Gil Alterovitz, Xiao-Ying Meng, Franck Grall, Aristoteles A. N. Giagounidis, Giannoula Klement, Ulrich Steidl, Hasan H. Otu, Akos Czibere, Wolf C. Prall, Christof Iking-Konert, Michelle Shayne, Marco F. Ramoni, Norbert Gattermann, Rainer Haas, Constantine S. Mitsiades, Eric T. Fung, Towia A. Libermann

Department of Electrical and Computer Engineering: Faculty Publications

Myelodysplastic syndromes (MDS) are among the most frequent hematologic malignancies. Patients have a short survival and often progress to acute myeloid leukemia. The diagnosis of MDS can be difficult; there is a paucity of molecular markers, and the pathophysiology is largely unknown. Therefore, we conducted a multicenter study investigating whether serum proteome profiling may serve as a noninvasive platform to discover novel molecular markers for MDS. We generated serum proteome profiles from 218 individuals by MS and identified a profile that distinguishes MDS from non-MDS cytopenias in a learning sample set. This profile was validated by testing its ability to …


Collaborative Image Transmissions Based On Region And Path Diversity In Wireless Sensor Network, Honggang Wang, Dongming Peng, Wei Wang, Hamid Sharif, Hsiao-Hwa Chen Jan 2007

Collaborative Image Transmissions Based On Region And Path Diversity In Wireless Sensor Network, Honggang Wang, Dongming Peng, Wei Wang, Hamid Sharif, Hsiao-Hwa Chen

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

Many Sensor applications such as monitoring and surveillance may require image sensor array to conduct collaborative image transmissions in Wireless Sensor Networks (WSN). The large size image transmissions cause bottlenecks in WSN due to the limited energy resources and network capacity. In this paper, we propose a collaborative transmission scheme for image sensors to utilize inter-sensor correlations to decide transmission patterns based on transmission path diversities, which achieves minimal energy consumption, balanced sensor lifetime and required image quality. This optimization scheme not only allows each image sensor to transmit optimal fractions of the overlapped images through appropriate transmission paths in …


A Small Chip Area 12-B 300ms/S Current Steering Cmos D/A Converter Based On A Laminated-Step Layout Technique, Byungseung Lee, Byungill Kim, Juneseok Lee, Sanghoon Hwang, Minkyu Song, Tad Wysocki Jan 2007

A Small Chip Area 12-B 300ms/S Current Steering Cmos D/A Converter Based On A Laminated-Step Layout Technique, Byungseung Lee, Byungill Kim, Juneseok Lee, Sanghoon Hwang, Minkyu Song, Tad Wysocki

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

A 12-b 300MSPS Current-Steering DAC with 0.13um CMOS technology is presented. In order to reduce the chip area, a laminated-step layout technique is proposed. Based on this technique, the occupied DAC core size is only 0.26mm2 even in 12-b resolution. Further, a current auto-averaging technique, an output impedance enhancement circuit, and the novel latched switching cell logic are discussed to keep the desired 12- b DAC performance. The measured results are within ±1LSB for DNL. The measured SFDR is 70dB under Nyquist output frequency with 50mW power dissipation at 3.3V power supply.


A Simple Orthogonal Space-Time-Polarization Block Code, B. J. Wysocki, Tadeusz Wysocki, J. Seberry, S. Spence Adams, H. Sharif Jan 2007

A Simple Orthogonal Space-Time-Polarization Block Code, B. J. Wysocki, Tadeusz Wysocki, J. Seberry, S. Spence Adams, H. Sharif

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

This letter proposes a simple but highly efficient technique to jointly utilize space, time, and polarization diversities. The technique is based on extending orthogonal space-time block codes into the quaternion domain and utilizing a description of the dual-polarized signal by means of quaternions, which are a generalization of complex numbers. In the given example, the achievable performance gain for two transmit and one receive antennas is approximately 6 dB at a bit error rate of 10-4 when compared with the Alamouti code.


Design Concepts And Process Analysis For Transmuter Fuel Manufacturing, Georg F. Mauer Jan 2007

Design Concepts And Process Analysis For Transmuter Fuel Manufacturing, Georg F. Mauer

Fuels Campaign (TRP)

The safe and effective manufacturing of actinide-bearing fuels for any transmutation strategy requires that the entire manufacturing process be contained within a shielded hot cell environment. To ensure that the fabrication process is feasible, the entire process must be designed for remote operation. The equipment must be reliable enough to perform over several decades, and also easy to maintain or repair remotely. The facility must also be designed to facilitate its own decontamination and decommissioning. In addition to these design factors, the potential viability of any fuel fabrication process will also be impacted by a number of variables, such as …


A Cognitive Robotics Approach To Comprehending Human Language And Behaviors, Deryle W. Lonsdale, D. Paul Benjamin, Damian Lyons Jan 2007

A Cognitive Robotics Approach To Comprehending Human Language And Behaviors, Deryle W. Lonsdale, D. Paul Benjamin, Damian Lyons

Faculty Publications

The ADAPT project is a collaboration of researchers in linguistics, robotics and artificial intelligence at three universities. We are building a complete robotic cognitive architecture for a mobile robot designed to interact with humans in a range of environments, and which uses natural language and models human behavior. This paper concentrates on the HRI aspects of ADAPT, and especially on how ADAPT models and interacts with humans.