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Manual Control (manual + control)

Distribution by Scientific Domains
Medical Sciences33%

Selected Abstracts

Resilience of Native Plant Community Following Manual Control of Invasive Cinchona pubescens in Galápagos

RESTORATION ECOLOGY, Issue 2010
Heinke Jäger
As invasive plant species are a major driver of change on oceanic islands, their control is an important challenge for restoration ecology. The post-control recovery of native vegetation is crucial for the treatments to be considered successful, but few studies have evaluated the effects of control measures on both target and non-target species. To investigate the efficiency of manual control of Cinchona pubescens and its impacts on the sub-tropical highland vegetation of Santa Cruz Island, Galápagos, vegetation was sampled before and up to two years after control was carried out in permanent sampling plots. Manual control significantly reduced Cinchona density. Due to regeneration from the seed or bud bank, follow-up control is required, however, for long-term success. Despite heavy disturbance from tree uprooting, herbaceous angiosperms were little affected by the control actions, whereas dominant fern species declined in cover initially. Most native, endemic, and other introduced species regained their pre-control levels of cover 2 years after control; some species even exceeded them. The total number of species significantly increased over the study period, as did species diversity. The native highland vegetation appeared to be resilient, recovering to a level probably more characteristic of the pre-invasion state without human intervention after Cinchona control. However, some introduced species seemed to have been facilitated by the control actions, namely Stachys agraria and Rubus niveus. Further monitoring is needed to confirm the long-term nature of vegetation change in the area. [source]

Evaluation of semi-autonomous convoy driving

JOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 11-12 2008
James Davis
Autonomous mobility technologies may have applications to manned vehicle convoy operations,they have the ability to enhance both system performance and operator capability. This effort examines the potential impact of introducing semi-autonomous mobility [Convoy Active Safety Technologies (CAST)] into manned vehicles. Twelve civilians with experience driving military vehicles in convoy-type operations participated in this experiment. For the experiment, they were tasked with following a lead vehicle while completing a concurrent security task (scanning the local environment for targets). The control of the manned vehicle was varied between CAST and manual control at several different speed levels. Several objective speed and accuracy variables along with subjective operator assessment variables were examined for each task. The results support the potential benefits of incorporating semi-autonomous mobility technologies into manned vehicle convoy operations. The semi-autonomous mobility system was associated with significantly better performance in several aspects of operator situational awareness and convoy integrity, including enhanced target identification, improved maintenance of following distance, and improved performance for unanticipated stops. This experiment also highlighted a critical human factors issue associated with the incorporation of autonomy in real-world applications: participants felt that, overall, they outperformed the semi-autonomous system on the simulated convoy operation. The operator's perception of the system's performance could potentially affect his or her willingness to use the system in real-world applications. This experiment demonstrated that enhancements to overall system performance in real-world applications are achieved by considering both technological and human factors solutions. Published 2008 Wiley Periodicals, Inc., [source]

Comparison of closed loop vs. manual administration of propofol using the Bispectral index in cardiac surgery

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 3 2009
J. AGARWAL
Background: In recent years, electroencephalographic indices of anaesthetic depth have facilitated automated anaesthesia delivery systems. Such closed-loop control of anaesthesia has been described in various surgical settings in ASA I,II patients (1,4), but not in open heart surgery characterized by haemodynamic instability and higher risk of intra-operative awareness. Therefore, a newly developed closed-loop anaesthesia delivery system (CLADS) to regulate propofol infusion by the Bispectral index (BIS) was compared with manual control during open heart surgery. Methods: Forty-four adult ASA II,III patients undergoing elective cardiac surgery under cardiopulmonary bypass were enrolled. The study participants were randomized to two groups: the CLADS group received propofol delivered by the CLADS, while in the manual group, propofol delivery was adjusted manually. The depth of anaesthesia was titrated to a target BIS of 50 in both the groups. Results: During induction, the CLADS group required lower doses of propofol (P<0.001), resulting in lesser overshoots of BIS (P<0.001) and mean arterial blood pressure (P=0.004). Subsequently, BIS was maintained within ± 10 of the target for a significantly longer time in the CLADS group (P=0.01). The parameters of performance assessment, median absolute performance error (P=0.01), wobble (P=0.04) and divergence (P<0.001), were all significantly better in the CLADS group. Haemodynamic stability was better in the CLADS group and the requirement of phenylephrine in the pre-cardiopulmonary bypass period as well as the cumulative dose of phenylephrine used were significantly higher in the manual group. Conclusion: The automated delivery of propofol using CLADS was safe, efficient and performed better than manual administration in open heart surgery. [source]

Resilience of Native Plant Community Following Manual Control of Invasive Cinchona pubescens in Galápagos

RESTORATION ECOLOGY, Issue 2010
Heinke Jäger
As invasive plant species are a major driver of change on oceanic islands, their control is an important challenge for restoration ecology. The post-control recovery of native vegetation is crucial for the treatments to be considered successful, but few studies have evaluated the effects of control measures on both target and non-target species. To investigate the efficiency of manual control of Cinchona pubescens and its impacts on the sub-tropical highland vegetation of Santa Cruz Island, Galápagos, vegetation was sampled before and up to two years after control was carried out in permanent sampling plots. Manual control significantly reduced Cinchona density. Due to regeneration from the seed or bud bank, follow-up control is required, however, for long-term success. Despite heavy disturbance from tree uprooting, herbaceous angiosperms were little affected by the control actions, whereas dominant fern species declined in cover initially. Most native, endemic, and other introduced species regained their pre-control levels of cover 2 years after control; some species even exceeded them. The total number of species significantly increased over the study period, as did species diversity. The native highland vegetation appeared to be resilient, recovering to a level probably more characteristic of the pre-invasion state without human intervention after Cinchona control. However, some introduced species seemed to have been facilitated by the control actions, namely Stachys agraria and Rubus niveus. Further monitoring is needed to confirm the long-term nature of vegetation change in the area. [source]

Assessing the clinical or pharmaco-economical benefit of target controlled desflurane delivery in surgical patients using the Zeus® anaesthesia machine,

ANAESTHESIA, Issue 11 2009
B. Lortat-Jacob
Summary The Zeus® anaesthesia machine includes an auto-control mode which allows targeting of end-tidal volatile and inspired oxygen concentrations. We assessed the clinical benefits and economic impact of this target-controlled anaesthesia compared with conventional manually controlled anaesthesia. Eighty patients were randomly assigned to receive desflurane either with a fresh gas flow set by the anaesthetist or in auto-control mode. Drug delivery was adjusted to maintain bispectral index between 40,60 units and systolic arterial pressure under 15 mmHg above its pre-induction value (upper limit) and over 90 mmHg (lower limit). Blood pressure was maintained in the desired range for 89% and 91% of the maintenance period for auto-control and manual control respectively (p = 0.49). Bispectral index was in the desired range for 82% and 79% of the maintenance period, for auto-control and manual control respectively (p = 0.46). Oxygen consumption was more than halved by the use of auto-control mode, and mean (SD) desflurane consumption during surgery was 0.07 (0.04) vs 0.2 (0.07) ml.min,1 in auto-control and manual control respectively (p < 0.0001). The number of drug delivery adjustments per hour was significantly lower in auto-control mode (mean (SD) 7 (2) vs 15 (12); p < 0.0001). Thus, the auto-control mode provided similar haemodynamic stability and bispectral control as did conventional manually controlled anaesthesia, but led to a reduction in gas and vapour consumption with a more clinically acceptable workload. [source]