Turning Off the Lights: Automating SkySat Mission Operations

A common goal for satellite operations is to achieve a level of automation that minimizes human interaction, especially as constellation sizes increase. Planet’s SkySat fleet is a constellation of high resolution Earth imaging smallsats that has grown from three to fifteen satellites in three years. This rapid expansion, along with Planet’s goal of improving operational reliability, has necessitated automating operations to reduce manual effort to maintain the health and safety fleet. To address the growing amount of work required for anomaly triage, systems were created for automated anomaly response. These systems have removed the need to actively monitor satellite health and safety. Instead, operators rely on interrupt-driven alerts to inform them of an anomaly. With the goal of further decoupling fleet size from operator effort, the mission operations team is working to automate routine maintenance tasks. As a result, the number of person-hours needed to actively operate the fleet has seen a three-fold reduction per week while enabling a five-fold increase in on-orbit assets. The systems developed have enabled an operational posture that removes the need for 24/7 staffing at a dedicated operations center

7. Paging. Virtual Memory.

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Real-time hierarchical hypervisor

textBoth real-time virtualization and recursive virtualization are desirable properties of a virtual machine monitor (or hypervisor). Although the prospect for virtualization and even recursive virtualization has become better as the PC hardware becomes faster, the real-time systems community so far has not been able to reap much benefits. This is because no existing virtualization mechanism can properly support the stringent timing requirements needed by real-time systems. It is hard to do real-time virtualization, and it is even harder to do it recursively. In this dissertation, we propose a framework whereby the hypervisor is capable of running real-time guests and participating in recursive virtualization. Such a hypervisor is called a real-time hierarchical hypervisor. We first look at virtualization of abstract resource types from the real-time systems perspective. Unlike the previous work on recursive real-time partitioning that assumes fully-preemptable resources, we concentrate on other and often more practical types of scheduling constraints, especially the non-preemptive and limited-preemptive ones. Then we consider the current x86 architecture and explore the problems that need to be addressed for real-time recursive virtualization. We drill down on the problem that affects timing properties the most, namely, the recursive forwarding and delivery of interrupts, exceptions and intercepts. We choose the x86 architecture because it is popular and readily available, but it is by no means the only architecture of choice for real-time recursive virtualization. We conclude the research with an architecture-independent discussion on future possibilities in real-time recursive virtualization.Computer Science

The FCC Spectrum Auctions: An Early Assessment

This paper analyzes six spectrum auctions conducted by the Federal Communications Commission (FCC) from July 1994 to May 1996. These auctions were simultaneous multiple-round auctions in which collections of licenses were auctioned simultaneously. This auction form proved remarkably successful. Similar items sold for similar prices and bidders successfully formed efficient aggregations of licenses. Bidding behavior differed substantially in the auctions. The extent of bidder competition and price uncertainty played an important role in determining behavior. Bidding credits and installment payments also played a major role in several of the auctions.Auctions; Spectrum Auctions; Multiple-Round Auctions; Efficiency

Deficit Reduction Through Diversity: How Affirmative Action at the FCC Increased Auction Competition

In recent auctions for paging licenses, the Federal Communications Commission has granted businesses owned by minorities and women substantial bidding credits. In this article, Professors Ayres and Cramton analyze a particular auction and argue that the affirmative action bidding preferences, by increasing competition among auction participants, increased the government's revenue by $45 million. Subsidizing the participation of new bidders can induce established bidders to bid more aggressively. The authors conclude that this revenue- enhancing effect does not provide a sufficient constitutional justification for affirmative action-but when such justification is independently present, affirmative actions can cost the government much less than is currently thought.Auctions; Affirmative Action

Evaluation of Traditional Security Solutions in the SCADA Environment

Supervisory Control and Data Acquisition (SCADA) systems control and monitor the electric power grid, water treatment facilities, oil and gas pipelines, railways, and other Critical Infrastructure (CI). In recent years, organizations that own and operate these systems have increasingly interconnected them with their enterprise network to take advantage of cost savings and operational benefits. This trend, however, has introduced myriad vulnerabilities associated with the networking environment. As a result, the once isolated systems are now susceptible to a wide range of threats that previously did not exist. To help address the associated risks, security professionals seek to incorporate mitigation solutions designed for traditional networking and Information Technology (IT) systems. Unfortunately, the operating parameters and security principles associated with traditional IT systems do not readily translate to the SCADA environment. Security solutions for IT systems focus primarily on protecting the confidentiality of system and user data. Alternatively, SCADA systems must adhere to strict safety and reliability requirements and rely extensively on system availability. Mitigation strategies designed for traditional IT systems must first be evaluated prior to deployment on a SCADA system or risk adverse operational impacts such as a catastrophic oil spill, poisoning a water supply, or the shutdown of an electrical grid. This research evaluates the suitability of deploying a Host-Based Intrusion Detection System (IDS) to the Department of Defense SCADA fuels system. The impacts of the Host Intrusion Prevention System (HIPS) installed on the SCADA network\u27s Human Machine Interface (HMI) is evaluated. Testing revealed that the HIPS agent interferes with the HMI\u27s system services during startup. Once corrected, the HMI and connected SCADA network inherit the protections of the HIPS security agent and defenses associated with the Host-Based Security System

Experiences running NASTRAN on the Microvax 2 computer

The MicroVAX operates NASTRAN so well that the only detectable difference in its operation compared to an 11/780 VAX is in the execution time. On the modest installation described here, the engineer has all of the tools he needs to do an excellent job of analysis. System configuration decisions, system sizing, preparation of the system disk, definition of user quotas, installation, monitoring of system errors, and operation policies are discussed

LOST IN SPACE: THE SURPRISING ROLE OF INFORMATION SPATIAL LAYOUT

LOST IN SPACE: THE SURPRISING ROLE OF INFORMATION SPATIAL LAYOUTJooyoung Jang, M.S.University of Pittsburgh, 2009Prior research has found that information presentation formats matter for how easily people understand certain information and solve problems using the presented information. The major finding from those studies is that information should be presented in a type of format that cognitively best fits to characteristics of given problems. Much of this prior has focused on conceptual elements of presentation format (e.g., words vs. diagrams, or graphs vs. tables) rather than more physical elements. However, with effort and strategy considerations in mind, more physical elements may also influence performance. Here, I focused on an understudied physical element that is pragmatically important and potentially theoretically exciting: the spatial layout of the information. Specifically, is there a difference between superimposed information (e.g., presented in a pile of pages) and distributed information (e.g., when the same pages of information is spread out sticking on a wall)? This question originated from an observation of meteorologists making weather forecasts. In an earlier study, meteorologists made a forecast in two conditions: mapwall and computer. Although the computer user could use animations and comparisons, there was no difference in accuracy but there was a large, nearly 50% time difference: Mapwall users made predictions far faster than computer users. The purpose of this master's project was to develop a lab task to replicate the effect and to reveal the underlying mechanism. The results showed a large speedup effect of the distributed format, but only on a task involving information integration. There, distributed task speed was almost twice as fast. An underlying mechanism for the effect, the strategy selection hypothesis, was also tested