Integrating operational and risk information with system risk models in air traffic control

Cognition, Technology & Work - The next generation Air Transport Management (ATM) requires performance-based safety management that is fully integrated into seamless operational management. To...     

Managing emergencies and abnormal situations in air traffic control (part II): Teamwork strategies

Team performance has been studied in many safety-critical organizations including aviation, nuclear power plant, offshore oil platforms and health organizations. This study looks into teamwork strategies that air traffic controllers employ to manage emergencies and abnormal situations. Two field studies were carried out in the form of observations of simulator training in emergency and unusual scenarios of novices and experienced controllers. Teamwork strategies covered aspects of team orientation and coordination, information exchange, change management and error handling. Several performance metrics were used to rate the efficiency of teamwork and test the construct validity of a prototype model of teamwork. This is a companion study to an earlier investigation of taskwork strategies in the same field (part I) and contributes to the development of a generic model for Taskwork and Teamwork strategies in Emergencies in Air traffic Management (T²EAM). Suggestions are made on how to use T²EAM to develop training programs, assess team performance and improve mishap investigations.     

Ubiquitous Agents for Ambient Ecologies

The cost of state-of-the-art devices and robots is critical for the uptake of Ambient Intelligence (AmI). One way to utilize low-cost hardware for both devices and robots is to run smart software remotely as agents deployed on computationally rich environments. In this context, the devices and the robots can be seen as the Avatars of agents, while the way devices and agents are related may be considered as an Ambient Ecology. We show how the application of a middleware platform called EVATAR realizes this vision by exemplifying the main issues with a multi-robot and a smart-home scenarios.     

Effect of creatine supplementation on sprint exercise performance and muscle metabolism

The aim of the present study was to examine the effect of creatine supplementation (CrS) on sprint exercise performance and skeletal muscle anaerobic metabolism during and after sprint exercise. Eight active, untrained men performed a 20-s maximal sprint on an air-braked cycle ergometer after 5 days of CrS [30 g creatine (Cr) + 30 g dextrose per day] or placebo (30 g dextrose per day). The trials were separated by 4 wk, and a double-blind crossover design was used. Muscle and blood samples were obtained at rest, immediately after exercise, and after 2 min of passive recovery. CrS increased the muscle total Cr content (9.5 +/- 2.0%, P < 0.05, mean +/- SE); however, 20-s sprint performance was not improved by CrS. Similarly, the magnitude of the degradation or accumulation of muscle (e.g., adenine nucleotides, phosphocreatine, inosine 5'-monophosphate, lactate, and glycogen) and plasma metabolites (e.g. , lactate, hypoxanthine, and ammonia/ammonium) were also unaffected by CrS during exercise or recovery. These data demonstrated that CrS increased muscle total Cr content, but the increase did not induce an improved sprint exercise performance or alterations in anaerobic muscle metabolism.     

A novel approach to characterization of progressive breakdown in high-k/metal gate stacks

Dielectric breakdown (BD) of nFETs with TiN metal gates and HfO₂/interfacial layer with 1.09 nm EOT is studied. Occurrence of progressive BD at low current levels is demonstrated. A new measurement methodology for extraction of the PBD time and its dependence on gate voltage are reported.     

Agent‐oriented activity recognition in the event calculus: An application for diabetic patients

We present a knowledge representation framework on the basis of the Event Calculus that allows an agent to recognize complex activities from low‐level observations received by multiple sensors, reason about the life cycle of such activities, and take action to support their successful completion. Activities are multivalue fluents that change according to events that occur in the environment. The parameters of an activity consist of a unique label, a set of participants involved in the performing of the activity, and a unique goal associated with the activity revealing the activity's desired outcome. Our contribution is the identification of an activity life cycle describing how activities can be started, interrupted, suspended, resumed, or completed over time, as well as how these can be represented. The framework also specifies activity goals, their associated life cycle, and their relation with the activity life cycle. We provide the complete implementation of the framework, which includes an activity generator that automatically creates synthetic sensor data in the form of event streams that represent the everyday lifestyle of a type 1 diabetic patient. Moreover, we test the framework by generating very large activity streams that we use to evaluate the performance of the recognition capability and study its relative merits.     

Volumetric analysis of MRI data monitoring the treatment of polycystic kidney disease in a mouse model

Object  

The human condition autosomal dominant polycystic kidney disease (ADPKD) is characterized by the growth of cysts in the kidneys that increase renal volume and lead to kidney failure. Mice studies are performed for treatment development monitored with imaging. The analysis of the imaging data is typically manual, which is costly and potentially biased. This paper presents a reliable and reproducible method for the automated segmentation of polycystic mouse kidneys.     

Anchor‐free distance estimation: A new approach to distance estimation for multihop ad hoc wireless networks

In ad hoc wireless networks, devices that normally cannot directly communicate route their messages through intermediate nodes. The number of those nodes is called hop count, a useful metric in estimating the distance between 2 nodes. Current methods usually depend on special nodes, called anchors, that need accurate localization information, in order to calculate an estimate for the average distance traversed per hop. The drawback of this approach is that anchor nodes increase the overall cost and complexity of the system. To address this problem, this letter proposes a novel, anchor node–free algorithm that can achieve a useful estimate for actual distance between 2 nodes, by analytically finding an estimate for the average maximum distance traveled per hop and multiplying with the hop count. The only requirement is the a priori knowledge of the networks' node density and the node range. The performance of our method is compared with a recent anchor node–based method and is shown to yield similar location estimation accuracy, despite the fact that it does not use anchor nodes.     

Joining nitride ceramics

Nitride ceramics are gaining importance in advanced technology applications. Examples include high temperature engine components of Si₃N₄, heat dissipating electronic substrates of AlN, and chemically inert cutting tools of cubic BN. The effective and widespread use of nitrogen ceramics in these and other applications, however, depends on the ability to bond them to metals, as well as to other ceramics.

Bonding ceramics to metals is inherently difficult because of their non-metallic characteristics, and this can be aggravated for nitride ceramics by their tendency to dissociate in vacua. The successful production of reliably strong joints by diffusion bonding and brazing with reactive filler metals is discussed. Reference will be made to the joining of AlN, BN and particularly Si₃N₄ using alloys containing reactive elements, and comments will be made on the influence of process and parameters such as temperature, environment and ceramic surface preparation on the microstructure, mechanical properties and high temperature stability of interfaces.     

Circuit implications of gate oxide breakdown

A model for the oxide breakdown (BD) current–voltage (I–V) characteristics has been experimentally verified on CMOS inverters. The implications of oxide BD on the performance of various CMOS circuit elements are discussed. Examples are shown of cell stability and bitline differentials in static memory (SRAM), signal timing, and inverter chains.