7755497
Teaching Java Concurrency to CS vs IT Students: A Matter of Emphasis
A number of colleges and universities have recently added new degree programs in Information Technology (IT), or added IT components to existing Computer Science (CS) programs. Java language and technology are almost inescapable elements of both CS and IT programs. One of Java's more advanced features, languagelevel support for concurrency in the form of explicit multithreading, is important to both CS and IT students, but for different reasons. Teaching Java concurrency to CS and IT students, therefore, presents different challenges and requires emphasizing the topic in different ways. We discuss these issues, and present our experiences from CS and IT classes taught recently, in which Java concurrency was a topic.
6308382
Cooperative Rec-I-DCM3: A Population-Based Approach for Reconstructing Phylogenies
In this paper, we study the use of cooperation as a technique for designing faster algorithms for reconstructing phylogenetic trees. Our focus is on the use of cooperation to reconstruct trees based on maximum parsimony. Our baseline algorithm is Rec-I-DCM3, the best-performing MP algorithm known-to-date. Our results demonstrate that cooperation does improve the performance of the baseline algorithm by at least an order of magnitude in terms of running time. The use of cooperation also established a new best known score on one of our datasets.
402019
Conversation trees and threaded chats
Chat programs and instant messaging services are increasingly popular among Internet users. However, basic issues with the interfaces and data structures of most forms of chat limit their utility for use in formal interactions (like group meetings) and decision-making tasks. In this paper, we discuss Threaded Text Chat, a program designed to address some of the deficiencies of current chat programs. Standard forms of chat introduce ambiguity into interaction in a number of ways, most profoundly by rupturing connections between turns and replies. Threaded Chat presents a solution to this problem by supporting the basic turn-taking structure of human conversation. While the solution introduces interface design challenges of its own, usability studies show that users' patterns of interaction in Threaded Chat are equally effective, but different (and possibly more efficient) than standard chat programs.
840524
Newsgroup Crowds and AuthorLines: visualizing the activity of individuals in conversational cyberspaces
We discuss the design, implementation and evaluation of two related visualizations of authors' activities in Usenet newsgroups. Current Usenet news browsers focus on messages and thread structures while disregarding valuable information about the authors of messages and the participants of the various discussions. Newsgroup Crowds graphically represents the population of authors in a particular newsgroup. Authors are displayed according to the number of messages they contribute to each thread and the number of different days they appear in the space, illustrating and contrasting the interaction patterns of participants within the newsgroup. AuthorLines visualizes a particular author's posting activity across all newsgroups over a period of one year. This visualization reveals temporal patterns of thread initiation and reply that can broadly characterize the roles authors play in Usenet. We report the results of a user study that explored the value of these interfaces for developing high-level awareness of the activity and population in these conversational spaces. We suggest that interfaces that convey information about the social histories of populations and individuals may support better selection and evaluation of newsgroup content.
52819119
Video skimming and characterization through the combination of image and language understanding
Digital video is rapidly becoming important for education, entertainment and a host of multimedia applications. With the size of the video collections growing to thousands of hours, technology is needed to effectively browse segments in a short time without losing the content of the video. We propose a method to extract the significant audio and video information and create a skim video which represents a very short synopsis of the original. The goal of this work is to show the utility of integrating language and image understanding techniques for video skimming by extraction of significant information, such as specific objects, audio keywords and relevant video structure. The resulting skim video is much shorter; where compaction is as high as 20:1, and yet retains the essential content of the original segment. We have conducted a user-study to test the content summarization and effectiveness of the skim as a browsing tool.
14666057
Video skimming and characterization through the combination of image and language understanding techniques
Digital video is rapidly becoming important for education, entertainment, and a host of multimedia applications. With the size of the video collections growing to thousands of hours, technology is needed to effectively browse segments in a short time without losing the content of the video. We propose a method to extract the significant audio and video information and create a "skim" video which represents a very short synopsis of the original. The goal of this work is to show the utility of integrating language and image understanding techniques for video skimming by extraction of significant information, such as specific objects, audio keywords and relevant video structure. The resulting skim video is much shorter, where compaction is as high as 20:1, and yet retains the essential content of the original segment.
5888435
Visualization components for persistent conversations
An appropriately designed interface to persistent, threaded conversations could reinforce socially beneficial behavior by prominently featuring how frequently and to what degree each user exhibits such behaviors. Based on the data generated by the Netscan data-mining project [9], we have developed a set of tools for illustrating the structure of discussion threads like those found in Usenet newsgroups and the patterns of participation within the discussions. We describe the benefits and challenges of integrating these tools into a multi-faceted dashboard for navigating and reading discussions in social cyberspaces like Usenet and related interaction media. Visualizations of the structure of online discussions have applications for research into the sociology of online groups as well as possible interface designs for their members.