Physical Sciences and Mathematics Commons^™

A Fast Connection-Time Redirection Mechanism For Internet Application Scalability, Michael Haungs, Raju Pandey, Earl Barr, J. Fritz Barnes

Computer Science and Software Engineering

Applications that are distributed, fault tolerant, or perform dynamic load balancing rely on redirection techniques, such as network address translation (NAT), DNS request routing, or middleware to handle Internet scale loads. In this paper, we describe a new connection redirection mechanism that allows applications to change end-points of communication channels. The mechanism supports redirections across LANs and WANs and is application-independent. Further, it does not introduce any central bottlenecks. We have implemented the redirection mechanism using a novel end-point control session layer. The performance results show that the overhead of the mechanism is minimal. Further, Internet applications built using this …

Measuring Packet Reordering, John M. Bellardo, Stefan Savage

Computer Science and Software Engineering

The Internet architecture provides an unsequenced datagram delivery service. Nevertheless, many higher-layer protocols, such as TCP, assume that packets are usually delivered in sequence, and consequently suffer significant degradation when packets are reordered in flight. While there have been several recent proposals to create protocols that adapt to reordering, evaluating their effectiveness requires understanding the dynamics of the reordering processes prevalent in the Internet. Unfortunately, Internet packet sequencing is a poorly characterized and understudied behavior. This failing can be largely attributed to the lack of accurate and universally applicable methods for measuring packet reordering. In this paper, we describe a …

Kinematic Path-Planning For Formations Of Mobile Robots With A Nonholonomic Constraint, Timothy D. Barfoot, Christopher M. Clark, Stephen M. Rock, Gabriele M.T. D'Eleuterio

Computer Science and Software Engineering

A method of planning paths for formations of mobile robots with nonholonomic constraints is presented. The kinematics equations presented in this paper allow a general geometrical formation of mobile robots to be maintained while the group as a whole travels an arbitrary path. It is possible to represent a formation of mobile robots by a single entity with the same type of nonholonomic constraint as the individual members. Thus, any path-planner or control method may be used with the formation as would be applied to an individual robot. Equations are developed for changing the geometrical formation and hardware results are …

The Tegrid Semantic Web Application, Steven Gollery, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

Over the past several years there has been an increasing recognition of the shortcomings of message-passing data-processing systems that compute data without understanding, and the vastly superior potential capabilities of information-centric systems that incorporate an internal information model with sufficient context to support a useful level of automatic reasoning.

The key difference between a data-processing and an information-centric environment is the ability to embed in the information-centric software some understanding of the information being processed. The term information-centric refers to the representation of information in the computer, not to the way it is actually stored in a digital machine. This …

Proceedings Of The 2002 Onr Decision-Support Workshop Series: Transformation..., Collaborative Agent Design Research Center

Collaborative Agent Design (CAD) Research Center

In August of 1998 the Collaborative Agent Design Research Center (CADRC) of the California Polytechnic State University in San Luis Obispo (Cal Poly), approached Dr. Phillip Abraham of the Office of Naval Research (ONR) with the proposal for an annual workshop focusing on emerging concepts in decision-support systems for military applications. The proposal was considered timely by the ONR Logistics Program Office for at least two reasons. First, rapid advances in information systems technology over the past decade had produced distributed, collaborative computer-assistance capabilities with profound potential for providing meaningful support to military decision makers. Indeed, some systems based on …

The Role Of Discovery In Context-Building Decision-Support Systems, Steven J. Gollery, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

There are many sources of on-line information available to those responsible for making decisions in complex situations. However, most of that information is either intended for human use or is available only in custom or proprietary formats. Both of these conditions reduce the ability of computer software to perform automatic reasoning about this information. As a result, the usefulness of on-line information in intelligent decision-support systems is currently limited to the few sources that are implemented specifically for those systems. The vast mass of sources that do not fit that description are virtually invisible.

Current practices for integrating multiple information …

Data, Information, And Knowledge In The Context Of Sils, Michael A. Zang, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

Data, information, and knowledge are becoming increasingly common terms in the literature of the software industry. This terminology originated some time ago in the disciplines of cognitive science and artificial intelligence to reference three closely related but distinct concepts. Traditionally, mainstream software engineering has lumped all three concepts together as data and has only recently begun to distinguish between them. Unfortunately, the popular desire to distinguish between data, information, and knowledge within the mainstream has blurred the individual meanings of the words to the point where there is no longer a clear-cut distinction between them for most people. This problem …

Poet: The Online Preference Elicitation Tool, James Royalty, Robert Holland, Judy Goldsmith, Alex Dekhtyar

Computer Science and Software Engineering

If the goal of eliciting accurate user preferences over a complex value space is to be realized, the elicitation process must be through while at the same time not overly burdensome to the user. An ideal preference elicitation tool would maximize the information about preferences acquired from the user while minimizing the number of queries required. To this end, we present POET: the Online Preference Elicitation Tool.
POET is a graphical Java applet designed to elicit complex preference structures to form a utility function. Once the elicitation process is complete POET outputs the resulting utility function as an XML …

Context Building Information-Centric Decision-Support Systems, Steven J. Gollery, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

As the volume of data and human-centered information available to decision-makers continues to increase at an ever-accelerating rate, the need to represent information in software-processable formats becomes more apparent. At the same time, the availability of information from diverse sources through the World Wide Web provides the opportunity to widen the scope of input to decision-support systems, if this information can be made accessible through automated means. Past approaches to information-centric interoperability have been based on the use of a shared static object model, but this becomes impractical when we consider the loosely-coupled decentralized nature of the Web.

This paper …

Some Thoughts On Human Nature: A Discussion Of Human Strenghts And Weaknesses, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

This paper attempts to explore the behavioral characteristics of human beings from a point of view that is not based on inter-human comparisons, but on an examination of the intrinsic physical, biological, intellectual, emotional, and social characteristics of this species. It is argued that the experience-based nature of the human cognitive system greatly reduces our ability to adapt to changes in our environment, exploit opportunities, and create new knowledge. A fundamental biological survival instinct drives the human being to seek a level of certainty and security that is irreconcilable with a continuously changing and largely unpredictable environment. The symptoms of …

The Underlying Design Principles Of The Icdm Development Toolkit, Kym J. Pohl, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

For the past sixteen years the Collaborative Agent Design Research Center (CADRC) at the California Polytechnic State University (Cal Poly), San Luis Obispo has pursued the design and development of agent-based decision-support systems. Throughout this journey the CADRC has relied on a suite of development tools that greatly assist in the creation and management of such systems. This suite of tools is known as the Integrated Cooperative Decision-Making (ICDM) software development toolkit.

Not only does ICDM function as an accelerator (i.e., rapid development) and stabilizer (i.e., built-in robustness and fault tolerance) in the development of decision-support systems, but it also …

Special Issue On Integration Of Symbolic And Connectionist Systems, Paolo Frasconi, Marco Gori, Franz J. Kurfess, Alessandro Sperduti

Computer Science and Software Engineering

No abstract provided.

Conditionalization For Interval Probabilities, Alex Dekhtyar, Judy Goldsmith

Computer Science and Software Engineering

Conditionalization, i.e., computation of a conditional probability distribution given a joint probability distribution of two or more random variables is an important operation in some probabilistic database models. While the computation of the conditional probability distribution is straightforward when the exact point probabilities are involved, it is often the case that such exact point probability distributions of random variables are not known, but are known to lie in a particular interval.

This paper investigates the conditionalization operation for interval probability distribution functions under a possible world semantics. In particular, given a joint probability distribution of two or more random variables, …

The Value Of Ontology-Based, Service-Oriented, Distributed Systems In A High Bandwidth Environment, Steven J. Gollery, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

No abstract provided.

Applying Kinodynamic Randomized Motion Planning With A Dynamic Priority System To Multi-Robot Space Systems, Christopher M. Clark, Tim Bretl, Stephen Rock

Computer Science and Software Engineering

Presents a new motion planning system that can construct collision-free trajectories for groups of robots in dynamic environments, without global knowledge or high-bandwidth communication. The robots plan within a confined environment that consists of stationary and moving obstacles. Each robot plans independently using Kinodynamic Randomized Motion Planner techniques to construct its own trajectory that is free of collisions with moving obstacles and other robots. To resolve conflicts between robot trajectories, a new Dynamic Priority System (DPS) is introduced which gives the right of way to the robot whose local workspace is the most crowded. The kinodynamic randomized motion planner allows …

Building Web Applications With Servlets And Javaserver Pages, David S. Janzen

Computer Science and Software Engineering

Servlets and JavaServer Pages provide the ability to dynamically generate web pages using the Java programming language. Among other benefits, the use of Java on the server-side allows the web developer to directly implement object-oriented designs, utilize multiple threads of execution, and employ JDBC to communicate with a database. This tutorial will introduce Servlets and JavaServer Pages through UML diagrams, code samples, and an example web application.

Ontology-Based Semantic Classification Of Unstructured Documents, Ching Kang Cheng, Xiao Shan Pan, Franz J. Kurfess

Computer Science and Software Engineering

As more and more knowledge and information becomes available through computers, a critical capability of systems supporting knowledge management is the classification of documents into categories that are meaningful to the user. In a step beyond the use of keywords, we developed a system that analyzes the sentences contained in unstructured or semi-structured documents, and utilizes an ontology reflecting the domain knowledge for a semantic classification of the documents. An experimental system has been implemented for the analysis of small documents in combination with a limited ontology; an extension to larger sets of documents and extended ontologies, together with an …

Integrating Symbol-Oriented And Sub-Symbolic Reasoning Methods Into Hybrid Systems, Franz J. Kurfess

Computer Science and Software Engineering

Knowledge representation and reasoning methods in artificial intelligence almost exclusively rely on symbol-oriented methods: Statements describing aspects and objects of the system to be modeled are represented through symbols (mostly text strings), and these symbols are stored in a computer, and manipulated according to the inference rules prescribed by the reasoning method. This works reasonably well in situations where knowledge is available in explicit form, typically through experts or written documents. In situations where knowledge is only available implicitly, e.g. in large data sets, other methods, often based on statistical approaches, have been used more successfully. Many of these methods …

Human-Robot Interaction: Final Report For Darpa/Nsf Study On Human-Robot Interaction, Erika Rogers, Robin R. Murphy

Computer Science and Software Engineering

No abstract provided.