Modelling the relationship between planning, control, perception and execution behaviours in interactive worksystems

This paper presents a model of planning carried out by interactive worksystems which attempts: 1. To describe the relationship between planning, control, perception and execution behaviours; 2. To make explicit how these may be distributed across the user and physically separate devices. Such a model, it is argued, is more suitable to support HCI design practice than theories of planning in cognitive science which focus on problem-solving methods and representations. To demonstrate the application of the model to work situations, it is illustrated by examples drawn from an observational study of secretarial office administration

A case of effective single-session treatment for attention deficit and learning problems in a routine clinical practice : the value of a transdiagnostic approach to case formulation

This article reports a systematic clinical case study of the psychological assessment and treatment of Daniel (9), a coloured South African boy with a diagnosis of attention deficit hyperactivity disorder (ADHD) (inattentive type). The case is of scientific interest because: (1) there was only a single treatment session, in which contingency management training was delivered to Daniel’s parents and teacher; (2) there was evidence for the effectiveness of the intervention immediately and at two-year follow-up; (3) it documents the transportability to a South African context of an intervention developed by overseas research; (4) it documents the central role of case formulation in the delivery of effective psychological interventions; and (5) although Daniel met the criteria for ADHD, he also displayed symptoms of depression and social anxiety and the case supports the use of a transdiagnostic approach to case formulation. The conscientiousness with which his parents and teachers applied the programme was a major factor in the effectiveness of the intervention, and such rapid impact would not be possible where parents and teachers are unavailable or not co-operative. The publication of systematic case studies such as this one is important for the development of a local evidence-based practice in South Africa

A model of medical reception - the planning and control of multiple task work

This research follows in the Broadbent tradition of constructing a general theory to solve applied problems. The paper reports part of wider research intended to construct a framework for modelling the planning and control of multiple task work. The function of the framework is to support the solution of design problems associated with the performance of interactive planning and control worksystems. The study reported here used an initial version of the framework, based on a study of secretarial office administration, to construct a model of medical reception work. An observational study collected protocol data concerning a medical reception worksystem, comprising two receptionists and various office devices; its domain of application, comprising doctors, patients, their appointments, medical records etc.; and its performance, comprising the quality of medical reception work and the costs to the receptionists of performing that work. The data were then used in conjunction with the planning and control framework to construct the model of medical reception. The model includes physical and abstract structures and behaviours of the medical reception worksystem, as well as physical and abstract objects of its domain of application. Of particular interest for the solution of design problems is the model's differentiation of plan types into task plans, procedure plans, and activity plans. These plan types were used to extend the framework for the planning and control of multiple task work. The paper concludes with a brief illustration of how the model of medical reception might be used to support the solution of interactive worksystem design problems as they relate to performance. Future work to develop further the framework of planning and control of multiple task work and its application are discussed

Symbolic Reachability Analysis of B through ProB and LTSmin

We present a symbolic reachability analysis approach for B that can provide a significant speedup over traditional explicit state model checking. The symbolic analysis is implemented by linking ProB to LTSmin, a high-performance language independent model checker. The link is achieved via LTSmin's PINS interface, allowing ProB to benefit from LTSmin's analysis algorithms, while only writing a few hundred lines of glue-code, along with a bridge between ProB and C using ZeroMQ. ProB supports model checking of several formal specification languages such as B, Event-B, Z and TLA. Our experiments are based on a wide variety of B-Method and Event-B models to demonstrate the efficiency of the new link. Among the tested categories are state space generation and deadlock detection; but action detection and invariant checking are also feasible in principle. In many cases we observe speedups of several orders of magnitude. We also compare the results with other approaches for improving model checking, such as partial order reduction or symmetry reduction. We thus provide a new scalable, symbolic analysis algorithm for the B-Method and Event-B, along with a platform to integrate other model checking improvements via LTSmin in the future

Experimental Characterization of Gas Turbine Emissions at Simulated Flight Altitude Conditions

NASA's Atmospheric Effects of Aviation Project (AEAP) is developing a scientific basis for assessment of the atmospheric impact of subsonic and supersonic aviation. A primary goal is to assist assessments of United Nations scientific organizations and hence, consideration of emissions standards by the International Civil Aviation Organization (ICAO). Engine tests have been conducted at AEDC to fulfill the need of AEAP. The purpose of these tests is to obtain a comprehensive database to be used for supplying critical information to the atmospheric research community. It includes: (1) simulated sea-level-static test data as well as simulated altitude data; and (2) intrusive (extractive probe) data as well as non-intrusive (optical techniques) data. A commercial-type bypass engine with aviation fuel was used in this test series. The test matrix was set by parametrically selecting the temperature, pressure, and flow rate at sea-level-static and different altitudes to obtain a parametric set of data

Particulate Sizing and Emission Indices for a Jet Engine Exhaust Sampled At Cruise

Particle size and emission indices measurements for jet engines, primarily the Rolls Royce RB211 engines on a NASA 757 aircraft are reported. These data were used to estimate the fraction of fuel sulfur that was converted to particulates. These measurements were made in-situ with the sampling aircraft several kilometers behind the source. Some complimentary ground measurements on the same source aircraft and engines are also reported. Significant differences are seen between the ground observations and the in-situ observations, indicating that plume processes are changing the aerosol\u27s characteristics

The robustness of interdependent clustered networks

It was recently found that cascading failures can cause the abrupt breakdown of a system of interdependent networks. Using the percolation method developed for single clustered networks by Newman [Phys. Rev. Lett. {\bf 103}, 058701 (2009)], we develop an analytical method for studying how clustering within the networks of a system of interdependent networks affects the system's robustness. We find that clustering significantly increases the vulnerability of the system, which is represented by the increased value of the percolation threshold $p_c$ in interdependent networks.Comment: 6 pages, 6 figure

Planning for multiple task work: an analysis of a medical reception worksystem

This paper presents an investigation of interactive worksystem planning in the multiple task work domain of medical reception. In an observational study of a medical reception worksystem, three different types of plan were identified: the task plan, the procedure plan and the activity plan. These three types of plan were required for effective working in the domain of medical reception, because of the many similar concurrent tasks, the frequency of behaviour switching between tasks and the need for consistency within the worksystem. It is proposed, therefore, that to design effective interactive human-computer worksystems for the domain of medical reception (and possibly for other work domains of a similar nature), the designer must specify the three different types of plan and the relationships between them. The three types of plan in medical reception are discussed in the context of design issues such as the allocation of planning structures

The Influence of REE β-Diketone Complexes on the Corrosion Behaviour of Mild Steel and 304 SS in 3.5% NaCl Solution

In the present investigation, four REE β-diketone complexes, namely cerium acetylacetone, cerium hexafluoroacetylacetone, lanthanum acetylacetone, and lanthanum hexafluoroacetylacetone, were investigated as potential corrosion inhibitors for mild steel and 304 stainless steel in 3.5% NaCl solution. The corrosion-inhibition effects of the REE β-diketone complexes were investigated using weight-loss measurements and potentiodynamic polarisation scans. Surface analyses using optical microscopy and scanning electron microscopy (SEM) were used to investigate the morphology of the mild steel and 304 stainless steel after the weight-loss and potentiodynamic tests in 3.5% NaCl solution containing 0.5% mass per volume (m/v) concentration of the tested inhibitor. Fourier transform infrared spectroscopy and Raman spectroscopy were further used to probe the type of corrosion product film that forms on the surface of the tested samples. The obtained results revealed that the four REE β-diketone complexes are very effective inhibitors against corrosion of mild steel and 304 stainless steel in a 3.5% NaCl in a temperature range of 20–60 °C