Hypervisors, popularized by Xen and VMware, are quickly becoming commodity. They are appropriate for many usage scenarios, but there are scenarios that require system virtualization with high degrees of both isolation and efficiency. Examples include HPC clusters, the Grid, hosting centers, and PlanetLab. We present an alternative to hypervisors that is better suited to such scenarios. The approach is a synthesis of prior work on resource containers and security containers applied to general-purpose, timeshared operating systems. Examples of such container-based systems include Solaris 10, Virtuozzo for Linux, and Linux-VServer. As a representative instance of container-based systems, this paper describes the design and implementation of Linux-VServer. In addition, it contrasts the architecture of Linux-VServer with current generations of Xen, and shows how Linux-VServer provides comparable support for isolation and superior system efficiency.

The need to provide remote visualization of large datasets with adequate levels of quality and interactivity has become a major impediment to distributed collaboration in Computational Science. Although Image Based Rendering (IBR) techniques based on plenoptic functions have some important advantages over other approaches to this problem, they suffer from an inability to deal with issues of network latency and server load, due to the large size of the IBR databases they generate. Consequently, IBR techniques have been left largely unexplored for this purpose. In this paper we describe strategies for addressing these obstacles using Logistical Networking (LoN), which is a new and highly scalable approach to deploying storage as a shared communication resource. Leveraging LoN technology and infrastructure, we developed a remote visualization system based on concepts of light field rendering, an IBR method using a 4-D plenoptic function. Our system extends existing work on light fields by employing a modified method of parameterization and data organization that supports more efficient prefetching, caching and loss-less compression. Using this approach, we have been able to interactively browse multi-gigabyte, high-resolution light field databases across the wide area network at 30 frames per second.

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The main objective of this study is to assess the cost benefit associated with comprehensive eye exams as a tool for the early detection of diabetes, hypertension, and high cholesterol. A retrospective, claims-based analysis was performed using U.S.-based employees and spouses from a large, national database. Individuals who received first notification of disease as a result of an eye exam were compared to individuals who did not receive early detection and presumably learned of their condition after further disease progression. Total health plan costs, lost time costs, and termination rates were calculated for the 12-month period after the index date. A sizable population first learned of their chronic condition through eye exams as no other claims-based evidence was found to suggest prior knowledge of the condition. All three disease cohorts with early detection during an eye exam had lower first-year health plan costs, missed fewer work days, and were less likely to terminate employment than the respective comparison groups. As employers strive to better manage health and business outcomes, comprehensive eye health exams can provide an opportunity for early disease detection and associated cost savings through referral to primary care providers and condition management programs.