Bits Through Bufferless Queues

This paper investigates the capacity of a channel in which information is conveyed by the timing of consecutive packets passing through a queue with independent and identically distributed service times. Such timing channels are commonly studied under the assumption of a work-conserving queue. In contrast, this paper studies the case of a bufferless queue that drops arriving packets while a packet is in service. Under this bufferless model, the paper provides upper bounds on the capacity of timing channels and establishes achievable rates for the case of bufferless M/M/1 and M/G/1 queues. In particular, it is shown that a bufferless M/M/1 queue at worst suffers less than 10% reduction in capacity when compared to an M/M/1 work-conserving queue.Comment: 8 pages, 3 figures, accepted in 51st Annual Allerton Conference on Communication, Control, and Computing, University of Illinois, Monticello, Illinois, Oct 2-4, 201

StemNet: An Evolving Service for Knowledge Networking in the Life Sciences

Up until now, crucial life science information resources, whether bibliographic or factual databases, are isolated from each other. Moreover, semantic metadata intended to structure their contents is supplied in a manual form only. In the StemNet project we aim at developing a framework for semantic interoperability for these resources. This will facilitate the extraction of relevant information from textual sources and the generation of semantic metadata in a fully automatic manner. In this way, (from a computational perspective) unstructured life science documents are linked to structured biological fact databases, in particular to the identifiers of genes, proteins, etc. Thus, life scientists will be able to seamlessly access information from a homogeneous platform, despite the fact that the original information was unlinked and scattered over the whole variety of heterogeneous life science information resources and, therefore, almost inaccessible for integrated systematic search by academic, clinical, or industrial users

Empirical investigation of the relationship between use and impacts of collaborative information technologies

Collaborative information technologies (CIT) to support groups working together or collaborating to accomplish tasks is becoming increasingly popular. Practitioner reports suggest that collaboration can have a significant influence on business performance and can lead to a sustained competitive advantage in a turbulent global environment (Frost and Sullivan, 2006). However, despite the large investments that organizations have been making in CIT (Hansen and Nohria, 2004), recent empirical evidence suggests that the utilization of CIT in organizations across five global regions is surprisingly limited and it generally does not meet the expectations of the practitioner and academic communities, in spite of substantial efforts of organizations to make such technologies available/accessible to their end-users (Bajwa et al., 2008). Is it plausible that CIT use may not have substantial impacts or lead to impacts that are not desirable to organizations? Our research focuses on addressing this research question through a large-scale macro-level investigation

Organizational impacts of collaborative information technologies: Case studies and empirical evidence

Our research focuses on information technology (IT) enabled collaboration systems. We refer to these systems as Collaborative Information Technologies (CITs). Traditional collaboration systems were designed to improve performance of group members or teams by supporting communications and the flow of information. However, modern day CITs have the capabilities to support not only communication and information flow, but also the computing needs of teams/groups engaged in accomplishing tasks/projects. There are many CIT options that organizations can deploy to support team work with varying degrees of virtuality. While some of these technologies have been around for decades (for example, audio conferencing, video conferencing, proprietary groupware, group support systems etc.), others became popular more with the commercialization of the Internet (email, intranets, extranets, web conferencing, data conferencing etc.). Although most CITs support limited functionality for collaboration, integrated e-collaboration tools are beginning to emerge to support a range of functionality required in collaborative efforts [Munkvold and Zigurs 2005]. In recent years, the increasing popularity of CITs has triggered a large number of research investigations and the trend continues to grow. Much of this research has focused on groups as the unit of analysis. There have been only a few large scale organizational level studies exploring CITs. Moreover, for the most part, these studies have investigated specific/individual CITs despite the notion that most collaborative efforts should typically be supported by multiple tools. Some studies exploring adoption of multiple CITs have been undertaken [see Bayo-Moriones and Lera-Lopez 2007; Bajwa et al. 2008]. However, to our knowledge there are no large scale organizational level empirical studies exploring CIT impacts. Here we describe our efforts to explore post adoption impacts of CITs at the organization level

Adoption of collaboration information technologies in Australian and US organizations: a comparative study

Collaboration to accomplish tasks has taken on a new meaning over the past few years. The majority of organizations are viewing information technology (IT) as a key enabler to transcend time and distance barriers to collaborate efficiently and effectively. Despite this, we know very little about the macro level adoption of IT to support collaboration. This paper assesses the pattern of adoption of seven IT clusters to support task-oriented collaboration in US and Australian organizations. Data collected from one hundred and forty Australian organizations and one hundred and nineteen US organizations is analyzed to compare adoption patterns. Our results suggest that stand-alone e-mail systems, audio teleconferencing systems, and videoconferencing are the most widely adopted technologies to support collaboration in both countries while web-based tools and electronic meeting systems are the least commonly adopted. A further analysis of data suggests that promotion of collaboration, mode of collaboration, and the adoption of some IT clusters are affected by region. Implications of these findings are discussed along with some directions for practice and research

An exploratory investigation of the organizational impacts of collaborative information technology utilization in Australian organizations

In this paper, we extend the existing literature by exploring the organizational-level impacts of Collaborative Information Technology (CIT). We consider CIT as any information technology (IT) that supports collaboration tasks. Data was collected from 73 organizations in Australia to access organizational impacts of CITs. Our results indicate that CIT use for primary collaborative tasks (information and knowledge sharing, decision-making, report writing/information pooling), secondary collaborative tasks (communications, scheduling, and monitoring progress), and tertiary collaborative tasks (issue resolution and discussion and brainstorming) is positively and significantly associated with strategic, efficiency-oriented, and effectiveness-oriented organizational level impacts. Implications of our findings are discussed for practice and research

E-Collaboration Impacts in Australia and Hong Kong

This paper investigates e-collaboration impacts across organizations in Australia and Hong Kong. The two regions were selected because of diversity in geographical dispersion and cultural differences. A myriad of e-collaboration activities were included in the study. Data collected and analyzed from 73 organizations in Australia and 94 organizations in Hong Kong suggests that there are no significant differences in the level of electronic support for collaboration activities in both the regions. However, significant differences were detected in the perceived impacts of e-collaboration between the two study regions. Interestingly, there was high level of agreement on ranking of e-collaboration activities and perceived e-collaboration impacts in both the regions. Implications of our findings for practice and research are discussed