"‘Biometrics is at the forefront in our agenda for homeland security,’ declared Asa Hutchinson, the Department of Homeland Security's undersecretary for border and transportation security, at the 2004 Biometric Consortium Conference” [11].
Flashy retinal scanning and voice activated computers were once considered technologies for science fiction movies and novels. Nowadays,...
Functional programming is concerned with referential transparency, that is, given a certain function and its parameter, that the result will always be the same. However, it seems that this is violated in applications involving uncertainty, such as rolling a dice. This thesis defines the background of probabilistic programming and domain-specific...
The Elliptic Curve Digital Signature Algorithm (ECDSA) is a public key cryptosystem used for creation and verification of digital signatures in electronic documents. In this thesis, we created a Java applet that provides the functionality of the ECDSA using all of the NIST elliptic curves over GF(p). This applet was...
Protein secondary structure prediction plays a pivotal role in predicting protein folding in three-dimensions. Its task is to assign each residue one of the three secondary structure classes helix, strand, or random coil. This is an instance of the problem of sequential supervised learning in machine learning. This thesis describes...
Popular applications such as P2P file sharing, multiplayer gaming, videoconferencing, etc. rely on the efficiency of content distribution from a single source to multiple receivers. Most users of these applications are on the widely prevalent source constraint networks such as the Digital Subscriber Line (DSL) and wireless networks. Overlay multicast...
As broadband Internet becomes widely available, Peer-to-Peer (P2P) applications over the Internet are becoming increasingly popular. Such an example is a video multicast application in which, one source streams a video to a large number of destination nodes through an overlay multicast tree consisting of peers.
These overlay multicast-based applications,...
This thesis describes the implementation of an interface for querying established correspondences between anatomical structures across species. I was the main developer of this query engine, called the Comparative Anatomy Information System. My work involved developing methods to query the knowledge base, perform the specified comparison, display the anatomical hierarchies...
The computer game industry continues to progress toward realistic-looking character motion. However, even in state-of-the-art games, the use of motion capture data in character animation may result in errors such as “foot slipping,” where the feet do not match up with the floor properly during translation. Various algorithms have been...
The high cost of manually producing background characters creates a demand for a
way to automatically generate plausible behaviors. These background extras need to
behave in a manner that is believable such that they do not distract the focus of the
audience from the primary action occurring in the scene....
Media application on the internet has become more and more popular as the bandwidth of the network links increase. The bottleneck of the existing media systems is no longer the link bandwidth at user’s end, but the server’s ability to handle streaming requests. These existing streaming systems do not scale...
This thesis presents a domain specific visual language designed to allow coaches to create content that exhibits the complex 2D interactions observed in the game of American football. Coaches can visually program the content by using symbols and drawing primitives similar to those that they currently use to design static...
The thesis focuses on model-based approximation methods for reinforcement
learning with large scale applications such as combinatorial optimization problems.
First, the thesis proposes two new model-based methods to stablize the
value–function approximation for reinforcement learning. The first one is the
BFBP algorithm, a batch-like reinforcement learning process which iterates between...
We present an approach for generating a character’s response in anticipation of an impending impact. Protective anticipatory movement is built upon several simple actions that have been identified as response mechanisms in monkeys and in humans. These actions are parameterized by a model of the interaction based on the approaching...
Traditional application of Voronoi diagrams for space partitioning creates Voronoi regions, with areas determined by the generators’ relative locations and weights. Especially in the area of information space (re)construction, however, there is a need for inverse solutions; i.e., finding weights that result in regions with predefined areas. In this thesis,...
The code reuse problem is a common software engineering problem in scientific computing. As a prevailing programming language in many scientific fields, Fortran does not provide support to address this problem. One particular reason is that Fortran lacks the support for generic programming. By applying program-generation techniques, we developed two...
Although researchers have begun to explicitly support end-user programmers’ debugging by providing information to help them find bugs, there is little research addressing the right content to communicate to these users. The specific semantic content of these debugging communications matters because, if the users are not actually seeking the information...
This thesis presents a model for simulating individual pedestrian motion based on empirical data. The model keeps track of a pedestrian’s position, orientation, and body configuration and leverages motion capture data to generate plausible motion. Our model can automatically incorporate a pedestrian’s physical limitations when making movement decisions, since it...
Software maintenance accounts for a large portion of the software development cost, particularly the process of updating programs either to adapt for requirement change or to enhance design or efficiency. Currently, program updates are generally performed manually by programmers using text editors. This is an unreliable
method because syntax and...
Finding information can cost a significant amount of time, even when the information is already stored on the user’s local computer system. There is significant research aimed at reducing these time costs, but little research into exactly what these costs are or how they impact people’s use of tools and...
Oftentimes in visualization, the goal of using volume datasets is not just to visualize them but also to analyze and compare them. In order to compare the two volumes, we cannot take all the voxels into consideration. The size of a typical volume data set is quite large (maybe a...
The Line Integral Convolution (LIC) is a mainstay of flow visualization. It is, however, computationally intensive, which limits its interactivity. Also, when used to view three-dimensional (3D) vector fields, the resulting images are dense and cluttered, making it difficult to perceive the flow on the interior parts of the field....
Packet loss, delay and time-varying bandwidth are three main problems facing multimedia streaming applications over the Internet. Existing techniques such as Media-aware network protocol, network adaptive source and channel coding, etc. have been proposed to either overcome or alleviate these drawbacks of the Internet. But these techniques either need specialized...
3D datasets acquire great importance in the context of medical imaging. In this thesis we survey and enhance solutions to problems inherently associated with 3D datasets-processing time,noise and visualization. Efforts include development of a tool kit to provide a multi-threaded processing platform to cut processing time, produce real time visualization...
Spreadsheets are among the most widely used end-user programming systems. Unfortunately, there is a high incidence of errors in end-user spreadsheets, and some of these errors have high impact. In this dissertation, we describe techniques we have developed to help end users develop safer spreadsheets. As part of our research,...
Until recently, research has not considered whether the design of end-user programming environments, such as spreadsheets, multimedia authoring languages, and CAD systems, affects males and females differently. As a result, we began investigating how the two genders are impacted by end-user programming software and whether attention to gender differences is...
Accessing information on the Web has become ingrained into our daily lives, and we seek information from many different sources, including conference and journal publications, personal web pages, and others. Increasingly, web-based information retrieval systems such as web-based search engines, library on-line catalog systems, and subscription-based federated search systems are...
Most of the work so far in the subfield of Gender HCI has followed a theory-driven approach. Established theories, however, do not take into account specific issues that arise in end-user debugging. We suspected that there may be important information that we were overlooking. We therefore employed a methodology change:...
An n-bit Gray code is an ordered set of all 2n binary strings of length n. The
special property of this listing is that Hamming distance between consecutive vectors
is exactly 1. If the last and first codeword also have a Hamming distance 1 then the
code is said to...
Domain-independent automated planning is concerned with computing a sequence of actions that can transform an initial state into a desired goal state. Resource production domains form an interesting class of such problems, in that they typically require reasoning about concurrent durative-actions with continuous effects while minimizing some cost function. Although...
A basic tradeoff to consider when designing a distributed data-mining framework is the need for a compromise between the cost of communication and computation resources and the accuracy of the mining results. This is essentially a decision of whether it is more efficient to communicate all of the data to...
The goal of many machine learning problems can be formalized as the creation of a function that can properly classify an input vector, given a set of examples of that function. While this formalism has produced a number of success stories, there are notable situations in which it fails. One...
Image feature detection and matching are two critical processes for many computer vision tasks. Currently, intensity-based local interest region detectors and local feature-based matching methods are used widely in computer vision applications. But in some applications, such as biological object recognition tasks, within-class changes in pose, lighting, color, and texture...
There has been little research into how end-user programming environments can provide explanations that could fill a critical information gap for end-user debuggers – help with debugging strategy. To address this need, we designed and prototyped a video-based approach for explaining debugging strategy, and accompanied it with a text-only approach....
Nowadays, sports events are a significant part of the every-day entertainment with local, national, and international championships. A lot of money is invested by broadcasting companies to attract new and more viewers, acquire broadcasting rights, or send entire crews on site to cover such events. Journalists are among the few...
Remote sensors are becoming the standard for observing and recording ecological data in the field. Such sensors can record data at fine temporal resolutions, and they can operate under extreme conditions prohibitive to human access. Unfortunately, sensor data streams exhibit many kinds of errors ranging from corrupt communications to partial...
Protecting end-users privacy and building trust are the two most important factors needed to support the growth of ecommerce. The increased dependence on the Internet for a wide variety of daily transactions causes a corresponding loss in privacy for many users, as virtually all websites collect data from users directly...
There has been little prior research reporting strategy usage in end-user problem solving, and even less using gender as a factor. Without this type of information, enduser programming systems cannot know the “target” at which to aim, if they are to support male and female end-user programmers’ debugging. As a...
Building intelligent computer assistants has been a long-cherished goal of AI. Many intelligent assistant systems were built and fine-tuned to specific application domains. In this work, we develop a general model of assistance that combines three powerful ideas: decision theory, hierarchical task models and probabilistic relational languages. We use the...
Active participation and collaboration of community members are crucial to the continuation and expansion of open source software projects. Researchers have recognized the value of community in open source development and studied various aspects of it including structure of communities, motivations for participation, and collaboration among members. However, the majority...
Web applications are popular attack targets. Misuse detection systems use signature databases to detect known attacks. However, it is difficult to keep the database up to date with the rate of discovery of vulnerabilities. They also cannot detect zero-day attacks. By contrast, anomaly detection systems learn the normal behavior of...
Forward Error Correction and retransmission are two approaches used to reliably broadcast data in a network with poor quality of service. Taking some assumptions, it has been suggested that a retransmission based reliable broadcasting scheme using network coding should in theory provide an increase in bandwidth efficiency by combining packets...
DiskGrapher is a graphical visualization tool designed to help users better manage the
space on their hard drives. The main goal of DiskGrapher is to provide a different
visualization technique to display information, with the goal of providing a more intuitive
understanding of the directory structure of the disk than...
Factorization of integers is an important aspect of cryptography since it can be used as an
attack against some of the common cryptographic methods being used. There are
numerous methods in existence for factoring integers. Some of these are faster than
others for general numbers, while others work best on...
Fluid simulation is an interesting research problem with a wide range of applications including mechanical engineering, special effects in movies and games, and scientific simulation. Due to the complex nature of typical fluid flow equations, there are circumstances where a full volumetric fluid simulation may not be necessary to generate...
This thesis addresses the problem of learning dynamic Bayesian network (DBN) models to support reinforcement learning. It focuses on learning regression tree models of the conditional probability distributions of the DBNs. Existing algorithms presume that the stochasticity in the domain can be modeled as a deterministic function with additive noise....
In diversity combining automatic repeat request (ARQ), erroneous packets are combined together forming a single, more reliable, packet. In this thesis, we give a diversity combining scheme for the m-ary unidirectional channel. A system using the given scheme with a t-unidirectional error detecting code is able to correct up to...
Motion capture data is a digital representation of the complex temporal structure of human motion. Motion capture is widely used for data-driven animation in sports,medicine and entertainment, because of its ability to capture complex and realistic
motions. Due to its efficiency and cost, methods for reusing collections of motion capture...
Transportation infrastructure provides a vital service for the functionality of a
city. The efficient design of road networks poses an interesting topic in computer
science for digital content developers. For civil engineers, the visualization of
analysis results on infrastructure both efficiently and intuitively is crucial. The
following contributions are made...
Recent efforts in user-control of data-driven characters have focused on designing high-level graph data-structures that we call a Behavior Finite State Machine (BFSM). A BFSM is an interactive data-structure that benefits from the advantages of both motion graphs and blend-based techniques for generating animated motion. Each node in a BFSM...
Supervised learning is concerned with discovering the relationship between example sets of features and their corresponding classes. The traditional supervised learning formulation assumes that all examples are independent from one another. The order of the examples contains no information. Nonetheless, many problems have a sequential nature. Classifiers for these problems...