A Robust Architecture For Human Language Technology Systems

Early human language technology systems were designed in a monolithic fashion. As these systems became more complex, this design became untenable. In its place, the concept of distributed processing evolved wherein the monolithic structure was decomposed into a number of functional components that could interact through a common protocol. This distributed framework was readily accepted by the research community and has been the cornerstone for the advancement in cutting edge human language technology prototype systems.The Defense Advanced Research Program Agency (DARPA) Communicator program has been highly successful in implementing this approach. The program has fueled the design and development of impressive human language technology applications. Its distributed framework has offered numerous benefits to the research community, including reduced prototype development time, sharing of components across sites, and provision of a standard evaluation platform. It has also enabled development of client-server applications with complex inter-process communication between modules. However, this latter feature, though beneficial, introduces complexities which reduce overall system robustness to failure. In addition, the ability to handle multiple users and multiple applications from a common interface is not innately supported. This thesis describes the enhancements to the original Communicator architecture that address robustness issues and provide a multiple multi-user application environment by enabling automated server startup, error detection and correction. Extensive experimentation and analysis were performed to measure improvements in robustness due to the enhancements to the DARPA architecture. A 7.2% improvement in robustness was achieved on the address querying task, which is the most complex task in the human language technology system

DoR Communicator - October 2014

The October 2014 issue of the Division of Research newsletter.https://digitalcommons.fiu.edu/research_newsletter/1017/thumbnail.jp

CSE: U: Mixed-initiative Personal Assistant Agents

Specification and implementation of flexible human-computer dialogs is challenging because of the complexity involved in rendering the dialog responsive to a vast number of varied paths through which users might desire to complete the dialog. To address this problem, we developed a toolkit for modeling and implementing task-based, mixed-initiative dialogs based on metaphors from lambda calculus. Our toolkit can automatically operationalize a dialog that involves multiple prompts and/or sub-dialogs, given a high-level dialog specification of it. The use of natural language with the resulting dialogs makes the flexibility in communicating user utterances commensurate with that in dialog completion paths—an aspect missing from commercial assistants like Siri. Our results demonstrate that the dialogs authored with our toolkit support the end user’s completion of a human-computer dialog in a manner that is most natural to them—in a mixed-initiative fashion—that resembles human-human interaction

Multipath routing and QoS provisioning in mobile ad hoc networks

PhDA Mobile Ad Hoc Networks (MANET) is a collection of mobile nodes that can communicate with each other using multihop wireless links without utilizing any fixed based-station infrastructure and centralized management. Each mobile node in the network acts as both a host generating flows or being destination of flows and a router forwarding flows directed to other nodes. Future applications of MANETs are expected to be based on all-IP architecture and be capable of carrying multitude real-time multimedia applications such as voice and video as well as data. It is very necessary for MANETs to have an efficient routing and quality of service (QoS) mechanism to support diverse applications. This thesis proposes an on-demand Node-Disjoint Multipath Routing protocol (NDMR) with low broadcast redundancy. Multipath routing allows the establishment of multiple paths between a single source and single destination node. It is also beneficial to avoid traffic congestion and frequent link breaks in communication because of the mobility of nodes. The important components of the protocol, such as path accumulation, decreasing routing overhead and selecting node-disjoint paths, are explained. Because the new protocol significantly reduces the total number of Route Request packets, this results in an increased delivery ratio, smaller end-to-end delays for data packets, lower control overhead and fewer collisions of packets. Although NDMR provides node-disjoint multipath routing with low route overhead in MANETs, it is only a best-effort routing approach, which is not enough to support QoS. DiffServ is a standard approach for a more scalable way to achieve QoS in any IP network and could potentially be used to provide QoS in MANETs because it minimises the need for signalling. However, one of the biggest drawbacks of DiffServ is that the QoS provisioning is separate from the routing process. This thesis presents a Multipath QoS Routing protocol for iv supporting DiffServ (MQRD), which combines the advantages of NDMR and DiffServ. The protocol can classify network traffic into different priority levels and apply priority scheduling and queuing management mechanisms to obtain QoS guarantees

Educational Authoring Tools and the Educational Object Economy: Introduction to this Special Issue from the East/West Group

This special issue brings together perspectives from universities and publishers working on new media learning technologies. We begin by describing the way these organizations came to work together, before introducing the articles in this special issue. We then proceed to highlight the important issues that are emerging from their individual and collective efforts within the Group, and most recently from the author-reviewer debate in this issue. We now invite you to build on these discussions with your own contributions. <!-- NO reviewers NO demonstrations --

Doctor of Philosophy

dissertationHigh-performance supercomputers on the Top500 list are commonly designed around commodity CPUs. Most of the codes executed on these machines are message-passing codes using the message-passing toolkit (MPI). Thus it makes sense to look at these machines from a holistic systems architecture perspective and consider optimizations to commodity processors that make them more efficient in message-passing architectures. Described herein is a new User-Level Notification (ULN) architecture that significantly improves message-passing performance. The architecture integrates a simultaneous multithreaded (SMT) processor with a user-level network interface (NI) that can directly control the execution scheduling of threads on the processor. By allowing the network interface to control the execution of message handling code at the user level, the operating system (OS) related overhead for handling interrupts and user code dispatch related to notifications is eliminated. By using an SMT processor, message handling can be performed in one thread concurrent to user computation in other threads, thus most of the overhead of executing message handlers can be hidden. This dissertation presents measurements showing the OS overheads related to message-passing are significant in modern architectures and describes a new architecture that significantly reduces these overheads. On a communication-intensive real-world application, the ULN architecture provides a 50.9% performance improvement over a more traditional OS-based NIC and a 5.29-31.9% improvement over a best-of-class user-level NIC due to the user-level notifications