Machine learning and symbolic reasoning have been two main approaches to build intelligent systems. Symbolic reasoning has been used in many applications by making use of expressive symbolic representations to encode prior knowledge, conduct complex reasoning and provide explanations. Recently, machine learning has enabled various successful applications by learning from...
Raytracing is a long-established means to simulate physically accurate light propagation. Increasing availability and power of highly-parallel computing, such as cloud-based clusters and dedicated graphics hardware, means that rendering algorithms can produce high resolution output very quickly. This means raytracing can now be used as a forward model in optimization...
This work presents a cognitive model of argument structure construction acquisition and application based on analogy. The claims of this model are that (1) constructions, pairings of form and meaning, are a productive unit of linguistic analysis that account for a broader range of phenomena than traditional approaches; (2) human...
Neural networks have revolutionized the field of computer vision since they provide solutions to a number of previously unsolved problems and achieve promising performance both in terms of accuracy and computational efficiency. It has increasingly become recognized as providing high performance for applications as diverse as image classification, object detection,...
"The goal of our research has been to create software that extends the benefits of virtual reality
(VR) to mathematics education. We report on the design and evaluation of a VR application meant
to support students’ reasoning about objects in three-dimensional (3D) coordinate systems and to
explore the possibilities of...
Modern cosmological simulations are some of the world's largest and most demanding numerical computations that are run on state-of-the-art supercomputers. The codes use N-body and mesh-based methods in gravity-only solvers, and both Lagrangian and Eulerian schemes to model gas dynamics. Even complex astrophysical effects such as of star formation and...
Social media such as Twitter has risen as a powerful new communication medium for disseminating information on news, personal interests, experiences, and opinions. On social media, people talk about their lifestyle, health conditions and symptoms, search information on treatment options, and connect with people who have been through similar medical...
Understanding electrical circuits can be difficult for novices of all ages (Grotzer & Sudbury, 2000; Osborne, 1983; Shipstone, 1984; Tarciso Borges, 1999). Research shows that novices tend to have inadequate understandings of what happens at the level of atoms and electrons, leading to difficulty predicting the outcomes of electrical circuits...
Online platforms for learning to code such as Coursera, CodeCademy, and CodeSchool attract millions of learners and significantly expand the pool of self-starting developers, yet critical gaps in knowledge and experience remain between inexperienced learners and professionals. With vast amounts of professionally-authored source code made readily available by the client-server...
Smartphone is becoming ubiquitous and its sales proportions have exceeded the sales of personal computer systems since 2012. The number of smartphones will increase and perhaps at an even higher rate in the coming years. The computational capacity and numerous mobile applications benefit end user's daily life. At the same...
Serious games that are designed for educational purposes promote acquisition of knowledge and skills that are valued in the both the virtual realm and the real world. The challenge is to design serious games that leverage meaningful play to produce positive learning outcomes in the real world. I argue that...
Embedded systems are ubiquitous. Although many aspects of embedded system design and synthesis have received significant research attention, comparatively less attention has been given to new ideas in memory hierarchy design. This dissertation presents several new operating system and architecture techniques that use elements of the virtual and physical memory...
Technology users are technology observers as well, monitoring for problems or opportunities that might arise. Designing interfaces to support the monitoring of technology presents unique challenges for everything from detecting situations to responding to situations to changing the tools to match a changing operating environment or the observer's changing knowledge....
The light field is a 4D function that describes the flow of light in all directions through every point in free space. Digital cameras only capture a 2D projection of the 4D light field entering the camera lens. In this dissertation I modify the light field as it enters a...
The recent years have witnessed a large number of emerging applications in location based services, thanks to the wide spread use of GPS devices, cellular phones, RFID tags and mobile sensor nodes. A fundamental technology that enables such services is the efficient management of the vast volume of spatio-temporal information...
Virtual machine based distributed computing greatly simplifies and enhances adaptive/autonomic computing by lowering the level of abstraction, benefiting both resource providers and users. We are developing Virtuoso, a middleware system for virtual machine shared-resource computing (e.g. grids) that provides numerous advantages and overcomes many obstacles a user faces in using...
Live streaming media will form a significant fraction of Internet traffic in the near future. YouTube clips, animations and other video applications already account for more than sixty percent of Internet traffic and, at its current acceptance rate, streaming media could quickly surpass television in terms of the size of...
High-performance scientific computing in a modern age uses parallel techniques at a scale of hundreds of thousands of processors. These large-scale applications have I/O system workloads that are primarily driven by small, sparse I/O operations. While parallel file systems have provided application developers with scalable peak I/O bandwidth for large,...
We can represent many real-world data sets as data streams and/or high-dimensional data. Major stock market such as New York Stock Exchange (NYSE) trades more than 8000 financial products daily, which generates massive trading time series in the form of data streams. NetFlow and DNS querying data generated by real-time...
Humans routinely answer questions, make decisions, and provide explanations in the face of incomplete knowledge and time constraints. From everyday questions like "What will it cost to take that vacation?" to policy questions like "How can a carbon taxing scheme affect climate change?" we often do not have all the...
Living in a world where the machine and the Internet are ubiquitous, many people work and play online, in a world that is, ironically, often isolated and lonesome. While the Internet, as intended, connects us to information, products and services, it often draws us away from the rich connections that...
Constructing 3D objects from 2D images has been an active research area for decades. Given captured 2D information from various devices, different techniques were developed to assign 3D positions to the target object. However, methods for reconstructing a 3D model from a single 2D image remain largely manual and labor-intensive....
The optimization problems associated with adaptive and autonomic computing systems are often difficult to pose well and solve efficiently. A key challenge is that for many applications, particularly interactive applications, the user or developer is unlikely or unable to provide either the objective function f, or constraints. It is a...
Frictionless Information Systems (FIS) are a class of software systems that automatically bring users information and services related to what they are doing. These systems bridge the gap between the information a user wants and the repositories that contain the information - making the user more effective and informed. By...
With a large sphere of activity and ability to transfer data through wireless communication system, drones have proven to be more and more useful in both research and manufacturing. Whether by allowing researchers to collect measurements or filmmakers to attain aerial shots, the use of drone has allowed collection of...
Self-assembly is the process by which objects autonomously assemble into complexes. It is believed that self-assembly technology will ultimately permit the precise fabrication of complex nanostructures. Of particular interest are self-assembly systems that are highly programmable. That is, we can view a self-assembly system as analogous to a program, the...
In the last decade we have seen tremendous increases in computer and network speeds and performance, resulting in the emergence of wide-area distributed computing. However, its potential has not been realized, primarily due to lack of security and isolation, provisioning issues and challenges involved in developing distributed applications.
We present...
Image creation is an attempt to record a scene for presentation to a viewer. However, there is a precarious mapping between how a scene would be perceived and how an image is perceived. For example, although the human visual system does not have a strong absolute sense of color or...
Web users suffer from security and privacy threats. According to Symantec, 430 million new unique pieces of malware have been discovered in 2015, and over half a billion personal records were stolen or lost in the same year. Defense mechanisms can be classified as reactive approach and proactive approach. Reactive...
Spatial-temporal data mining, with data driven model and machine learning techniques, significantly benefit the traditional transportation research. This dissertation focus on three problems related to uncertain location data, lane-level traffic speed clustering and anomalous traffic speed prediction.
We take a first step towards combining the uncertain location data i.e., fusing...
Mobile traffic is expected to grow tenfold by 2019, topping 24 exabytes of monthly traffic and accounting for nearly half of all Internet traffic. This growth is driven by the increasing number of smart phones and tablets, and the data demands of high bandwidth services enabled by next-generation cellular networks...
Classic mechanism design studies the implementation of optimal systems or processes in the presence of multiple selfish and fully rational agents. The theory of mechanism design has been one of the most celebrated advances in the economics discipline, especially with regards to auctions Myerson (1981),Vickrey (1961), Clarke (1971), Groves (1973)....
Client-server architectures have been used for years, and many modern applications rely on this approach to be able to present rich and complex information to users without needlessly encumbering their local device with computation, and also to be able to keep all data in a (more-or-less) centrally available location, as...
How mental representations are constructed and how they evolve are central problems for cognitive science. Representation decisions help determine what computations are hard or easy. Structured, relational representations are a hallmark of human cognition. Developmental studies show that children do not perform as well as adults in tasks that require...
Consider the role of waiting rooms as informal learning environments. In this thesis, I examine a pediatric hematology and oncology clinic to evaluate the patient learning experience. Through staff interviews, waiting room observations, and a review of educational materials I argue that this process is in need of redirection. Most...
Broadband networks are one of the most economically significant and fastest growing sectors of the Internet. Recent studies have shown that providing broadband Internet access is instrumental for social and economic development. Several governments, as well as the UN, have gone so far as to label broadband access a basic...
Catalyzed by the invention of magnetic tape recording, audio production has transformed from technical to artistic, and the roles of producer, engineer, composer, and performer have merged for many forms of music. However, while these roles have changed, the way we interact with audio production tools has not and still...