Enroute flight planning: Evaluating design concepts for the development of cooperative problem-solving concepts

The goals of this research were to develop design concepts to support the task of enroute flight planning. And within this context, to explore and evaluate general design concepts and principles to guide the development of cooperative problem solving systems. A detailed model is to be developed of the cognitive processes involved in flight planning. Included in this model will be the identification of individual differences of subjects. Of particular interest will be differences between pilots and dispatchers. The effect will be studied of the effect on performance of tools that support planning at different levels of abstraction. In order to conduct this research, the Flight Planning Testbed (FPT) was developed, a fully functional testbed environment for studying advanced design concepts for tools to aid in flight planning

Enroute flight planning: The design of cooperative planning systems

Design concepts and principles to guide in the building of cooperative problem solving systems are being developed and evaluated. In particular, the design of cooperative systems for enroute flight planning is being studied. The investigation involves a three stage process, modeling human performance in existing environments, building cognitive artifacts, and studying the performance of people working in collaboration with these artifacts. The most significant design concepts and principles identified thus far are the principle focus

Megarian Local Adjudication: The Case of the Border Dispute between Epidauros and Corinth in 242-240 BCE (IG IV2.I.70 and 71)

Over the last quarter century, the study of interstate arbitration and the use of foreign judges to adjudicate disputes between city-states has been rejuvenated. This article re-examines the well-known Megarian adjudication of the border dispute between Epidauros and Corinth by the Achaean League in the 3rd century BCE, with a view to determining the reason for the Achaeans’ choice of Megara as judge and, more importantly, the acceptance of this decision by Corinth, given the less than friendly history between these two city-states

Design concepts for the development of cooperative problem-solving systems

There are many problem-solving tasks that are too complex to fully automate given the current state of technology. Nevertheless, significant improvements in overall system performance could result from the introduction of well-designed computer aids. We have been studying the development of cognitive tools for one such problem-solving task, enroute flight path planning for commercial airlines. Our goal was two-fold. First, we were developing specific systems designs to help with this important practical problem. Second, we are using this context to explore general design concepts to guide in the development of cooperative problem-solving systems. These designs concepts are described

Recent developments in the application of risk analysis to waste technologies.

The European waste sector is undergoing a period of unprecedented change driven by business consolidation, new legislation and heightened public and government scrutiny. One feature is the transition of the sector towards a process industry with increased pre-treatment of wastes prior to the disposal of residues and the co-location of technologies at single sites, often also for resource recovery and residuals management. Waste technologies such as in-vessel composting, the thermal treatment of clinical waste, the stabilisation of hazardous wastes, biomass gasification, sludge combustion and the use of wastes as fuel, present operators and regulators with new challenges as to their safe and environmentally responsible operation. A second feature of recent change is an increased regulatory emphasis on public and ecosystem health and the need for assessments of risk to and from waste installations. Public confidence in waste management, secured in part through enforcement of the planning and permitting regimes and sound operational performance, is central to establishing the infrastructure of new waste technologies. Well-informed risk management plays a critical role. We discuss recent developments in risk analysis within the sector and the future needs of risk analysis that are required to respond to the new waste and resource management agenda

Reduced-order PCA models for chemical reacting flows

pre-printOne of the most challenging aspects of turbulent combustion research is the development of reduced-order combustion models which can accurately reproduce the physics of the real system. The identification and utilization of the low dimensional manifolds in these system is paramount to understand and develop robust models which can account for turbulence-chemistry interactions. Recently, principal components analysis (PCA) has been given notable attention in its analysis of reacting systems, and its potential in reducing the number of dimensions with minimum reconstruction error. The present work provides a methodology which has the ability of exploiting the information obtained from PCA. Two formulations of the approach are shown: Manifold Generated from PCA (MG-PCA), based on a global analysis, and Manifold Generated from Local PCA (MG-L-PCA), based on performing the PCA analysis locally. The models are created using the co-variance matrix of a data-set which is representative of the system of interest. The reduced models are then used as a predictive tool for the reacting system of interest by transporting only a subset of the original state-space variables on the computational grid and using the PCA basis to reconstruct the non-transported variables. The present study first looks into the optimal selection of the subset of transported variables and analyzes the effect of this selection on the approximation of the state space and chemical species source terms. Then, a demonstration of various a posteriori cases is presented

Are the Health of the Nation's targets attainable? Postal survey of general practitioners' views

The Health of the Nation's targets were introduced by the government in 1992 as part of a strategic approach to health.1 We aimed, in 1996, to elicit the views of general practitioners on the attainability of these targets

Soot in combustion simulations

Journal ArticleSoot is the dominant source of radiative heat transfer from most practical flames. A review is presented of historical, empirical modelling approaches for estimating heat flux from fires and flames. These historical methods have drawn on empiricism to address the role of soot while seeking methods for including the multi-scale effects of soot formation and flame structure. Both soot concentration and flame temperature have been seen to be local phenomena with dimensions on the order of the diffusion and chemical (Batchelor) scales of the flame. The correlation between the local soot volume fraction and the local temperature field is needed for determining the radiant heat flux from the flame. By using high performance computers (hundreds to thousands of processors) Large Eddy Simulations (LES) can resolve structures on the scale of the pool diameter in pool Hires. Thus, air engulfment and visible flame structure are resolved. Manifolds for the gas-phase chemistry, soot formation, particle growth, soot diffusive/ thermophoretic transport are used to bridge the Batchelor and resolved (LES) scales

Megarian Moments. The Local World of an Ancient Greek City-State

Situated near the main traffic artery in Central Greece and surrounded by poleis that were more powerful, the ancient city-state of Megara was often a punching bag of others. In neighbouring Athens in particular, the Megarians were subject to all sorts of slander and expressions of chauvinism. The people of Megara, by default, had their own assessment of the world and their role in it. A highway to others, the Megarid, was a rich source of meaning and orientation to its inhabitants. This local backdrop, often misunderstood as petty or irrelevant, constituted a unique local discourse environment. Rather than telling a narrative history of Megara – unravelling its local history, as it were –, this volume delves into the local discourse of this ancient city. The various contributions all shed light on the prevailing identity of place, on what it meant to be from Megara. In doing so, the book unpacks the vibrant local life in a Greek city-state. In their endeavour to break the code of a local discourse and recreate its environment, the editors and authors also invite readers to rethink approximations toward the pluriverse of poleis in Greek Antiquity