Tournament-Style Debate as a Natural Resources Education Technique

Curricula in the natural resource professions are placing increased emphasis on course work dealing with the larger philosophical and value-related questions surrounding resource management. This development presents a challenge to instructors, particularly in terms of encouraging active student involvement in such courses. The use of tournament debate format provides one useful means for fostering such involvement while also aiding in the development of oral communication skills. The authors\u27 experience with the use of debate suggests that certain modifications to traditional debate format aid in its successful classroom use

Log-based architectures for general-purpose monitoring of deployed code

Runtime monitoring tools are invaluable for detecting various types of bugs, in both sequential and multi-threaded programs. However, these tools often slow down the monitored program by an order of magnitude or more [4], implying that the tools are ill-suited for always-on monitoring of deployed code. Fortunately, the emergence of chip multiprocessors as a dominant computing platform means that resources are available on-chip to assist in monitoring tasks. In this brief note, we advocate Log-Based Architectures (LBA) that exploit such on-chip resources in order to dramatically reduce the overhead of runtime program monitoring. Specifically, we propose adding hardware support for logging a main program's trace and delivering it to another (otherwise idle) processing core for inspection. A life-guard program running on this other core executes the desired monitoring task

Variation in general supportive and preventive intensive care management of traumatic brain injury: a survey in 66 neurotrauma centers participating in the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study

Abstract Background General supportive and preventive measures in the intensive care management of traumatic brain injury (TBI) aim to prevent or limit secondary brain injury and optimize recovery. The aim of this survey was to assess and quantify variation in perceptions on intensive care unit (ICU) management of patients with TBI in European neurotrauma centers. Methods We performed a survey as part of the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study. We analyzed 23 questions focused on: 1) circulatory and respiratory management; 2) fever control; 3) use of corticosteroids; 4) nutrition and glucose management; and 5) seizure prophylaxis and treatment. Results The survey was completed predominantly by intensivists (n = 33, 50%) and neurosurgeons (n = 23, 35%) from 66 centers (97% response rate). The most common cerebral perfusion pressure (CPP) target was > 60 mmHg (n = 39, 60%) and/or an individualized target (n = 25, 38%). To support CPP, crystalloid fluid loading (n = 60, 91%) was generally preferred over albumin (n = 15, 23%), and vasopressors (n = 63, 96%) over inotropes (n = 29, 44%). The most commonly reported target of partial pressure of carbon dioxide in arterial blood (PaCO2) was 36–40 mmHg (4.8–5.3 kPa) in case of controlled intracranial pressure (ICP) < 20 mmHg (n = 45, 69%) and PaCO2 target of 30–35 mmHg (4–4.7 kPa) in case of raised ICP (n = 40, 62%). Almost all respondents indicated to generally treat fever (n = 65, 98%) with paracetamol (n = 61, 92%) and/or external cooling (n = 49, 74%). Conventional glucose management (n = 43, 66%) was preferred over tight glycemic control (n = 18, 28%). More than half of the respondents indicated to aim for full caloric replacement within 7 days (n = 43, 66%) using enteral nutrition (n = 60, 92%). Indications for and duration of seizure prophylaxis varied, and levetiracetam was mostly reported as the agent of choice for both seizure prophylaxis (n = 32, 49%) and treatment (n = 40, 61%). Conclusions Practice preferences vary substantially regarding general supportive and preventive measures in TBI patients at ICUs of European neurotrauma centers. These results provide an opportunity for future comparative effectiveness research, since a more evidence-based uniformity in good practices in general ICU management could have a major impact on TBI outcome

Designing computer systems with MEMS-based storage

Abstract: "For decades the RAM-to-disk memory hierarchy gap has plagued computer architects. An exciting new storage technology based on microelectromechanical systems (MEMS) is poised to fill a large portion of this performance gap, significantly reduce power consumption, and enable many new classes of applications. This research explores the impact that several different MEMS-based storage designs will have on computer systems. Results from five application studies show these devices reduce application I/O stall times by 3-10X and improve overall application performance by 1.6-8.1X. Further, integrating MEMS-based storage as a disk cache achieves a 3.5X performance improvement over a standalone disk drive. Power consumption simulations show that MEMS-based storage devices use up to 10X less power than state-of-the-art low-power disk drives. Many of these improvements stem from the fact that average access times for MEMS-based storage are 10X faster than disks and that MEMS devices are able to rapidly move between active and power-down mode. Combined with the differences in the physical behavior of MEMS-based storage, these characteristics create numerous opportunities for restructuring the storage/memory hierarchy.

Using MEMS-based Storage Devices in Computer Systems (CMU-PDL-04-104)

MEMS-based storage is an interesting new technology that promises to bring fast, non-volatile, mass data storage to computer systems. MEMS-based storage devices (MEMStores) themselves consist of several thousand read/write tips, analogous to the read/write heads of a disk drive, which read and write data in a recording medium. This medium is coated on a moving rectangular surface that is positioned by a set of MEMS actuators. Access times are expected to be less than a millisecond with energy consumption 10-100X less than a low-power disk drive, while streaming bandwidth and volumetric density are expected to be around that of disk drives. This dissertation explores the use of MEMStores in computer systems, with a focus on whether systems can use existing abstractions and interfaces to incorporate MEMStores effectively, or if they will have to change the way they access storage to benefit from MEMStores. If systems can use MEMStores in the same way that they use disk drives, it will be more likely that MEMStores will be adopted when they do become available. Since real MEMStores do not yet exist, I present a detailed software model that allows their use to be explored under a variety of workloads. To answer the question of whether a new type of device requires changes to systems, I present a methodology that includes two objective tests for determining whether the benefit from a device is due to a specific difference in how that device accesses data or is just due to the fact that that device is faster, smaller, or uses less energy than current devices. I present a range of potential uses of MEMStores in computer systems, examining each under a number of user workloads, using the two objective tests to evaluate their efficacy. Using the evidence presented and the two objective tests, I show that systems can incorporate MEMStores easily and employ the same standard abstractions and interfaces used with disk systems. At a high level, the intuition is that MEMStores are mechanical storage devices, just like disk drives, only faster, smaller, and requiring less energy to operate. Accessing data requires an initial seek time that is distance-dependent, and, once access has begun, sequential access is the most efficient. This intuition is described in more detail, and the result is shown to hold for the range of uses presented

Designing Computer Systems with MEMS-based Storage

For decades the RAM-to-disk memory hierarchy gap has plagued computer architects. An exciting new storage technology based on microelectromechanical systems (MEMS) is poised to fill a large portion of this performance gap, significantly reduce system power consumption, and enable many new applications. This paper explores the system-level implications of integrating MEMS-based storage into the memory hierarchy. Results show that standalone MEMS-based storage reduces I/O stall times by 4-74X over disks and improves overall application runtimes by 1.9-4.4X. When used as on-board caches for disks, MEMS-based storage improves I/O response time by up to 3.5X. Further, the energy consumption of MEMS-based storage is 10-54X less than that of state-of-the-art low-power disk drives. The combination of the high-level physical characteristics of MEMS-based storage (small footprints, high shock tolerance) and the ability to directly integrate MEMS-based storage with processing leads to such new ap..

MEMS-based storage devices and standard disk interfaces: A square peg . . .

MEMS-based storage devices are a new technology that is significantly different from both disk drives and semiconductor memories. These differences motivate the question of whether they need new abstractions to be utilized by systems, or if existing abstractions will work well. This paper addresses this question by examining the fundamental reasons that the abstraction works for existing systems, and by showing that these reasons hold for MEMS-based storage. This result is borne out through several case studies of proposed roles MEMS-based storage devices may take in future systems, and potential policies that may be used to tailor systems&apos; access to MEMS-based storage. We argue that when considering the use of MEMS-based storage in systems, their performance should be compared to that of a hypothetical disk drive that matches the speed of a MEMS-based storage device. We discuss exceptional workloads that can use specific features of MEMS-based storage devices and that may require extensions to current abstractions. Also, we consider the ramifications of the assumptions that are made in today&apos;s models of MEMS-based storage devices