Clinical potential and design of programmable mechanical impedances for orthotic applications

A person with a moderate or severe motor disability will often use specialised or adapted tools to assist their interaction with a general environment. Such tools can assist with the movement of a person's arms so as to facilitate manipulation, can provide postural supports, or interface to computers, wheelchairs or similar assistive technologies. Designing such devices with programmable stiffness and damping may offer a better means for the person to have effective control of their surroundings. This paper addresses the possibility of designing some assistive technologies using impedance elements that can adapt to the user and the circumstances. Two impedance elements are proposed. The first, based on magnetic particle brakes, allows control of the damping coefficient in a passive element. The second, based on detuning the P-D controller in a servo-motor mechanism, allows control of both stiffness and damping. Such a mechanical impedance can be modulated to the conditions imposed by the task in hand. The limits of linear theory are explored and possible uses of programmable impedance elements are proposed.

Output envelope adjustment for an environmental fuzzy logic controller

A two-level fuzzy logic controller for use in air-conditioning systems is outlined in this paper. At the first level a simplified controller is produced from expert knowledge and envelope adjustment is introduced, while the second level provides a means for adapting this controller to different working spaces. The mechanism for adaption is easily implemented and can be used in real time. A series of simulations is presented to illustrate the proposed schema.

Quasi-decoupled fuzzy logic controller

The authors describe the design of a fuzzy logic controller for the control of a planar two-link manipulator. The plant is quasi-decoupled with respect to gravity. Complete decoupling is not achieved due to the nonoptimal nature of the expert rules. The performance of the fuzzy controller is compared to that of the critically damped computed torque controller. Results are presented complete with robustness tests.

Distributed fuzzy logic for building management systems using local operating networks

This paper describes the development of an experimental distributed fuzzy control system for heating and ventilation (HVAC) systems within a building. Each local control loop is affected by a number of local variables, as well as information from neighboring controllers. By including this additional information it is hoped that a more equal allocation of resources can be achieved.

Missing the logic of the text: Lord Butler’s report on intelligence on Iraqi weapons of mass destruction

This article focuses on the final report of Lord Butler’s review of British intelligence on weapons of mass destruction (WMD), specifically on its treatment of the accuracy of the use of intelligence on Iraqi WMD in a government dossier published in September 2002 ahead of the 2003 Iraq war. In the report, the demonstration of the accuracy of the “September Dossier” hinges on the insertion of tables that compare side-by-side quotations from this document and from intelligence assessments. The analysis of the textual and visual methods by which the report is written reveals how the logic of the comparative tables is missed in the Butler report: the logic of these tables requires that the comparison between quotations from the two documents should be performed at the level of their details but the Butler report performs its comparison only at a broad and general level.

Military competition and the emergence of nationalism: putting the logic of political survival into historical context

This essay aims to make a contribution to the conversation between IR and nationalism literatures by considering a particular question: What is the relationship between interstate military competition and the emergence of nationalism as a potent force in world politics? The conventional wisdom among international security scholars, especially neorealists, holds that nationalism can be more or less treated like a “technology” that allowed states to extract significant resources as well as manpower from their respective populations. This paper underlines some of the problems involved with this perspective and pushes forward an interpretation that is based on the logic of political survival. I argue that nationalism’s emergence as a powerful force in world politics followed from the “mutation” and absorption of the universalistic/cosmopolitan republican ideas that gained temporary primacy in Europe during the eighteenth century into particularistic nationalist ideologies. This transformation, in turn, can be best explained by the French Revolution’s dramatic impacts on rulers’ political survival calculi vis-à-vis both interstate and domestic political challenges. The analysis offered in this essay contributes to our understanding of the relationship between IR and nationalism while also highlighting the potential value of the political survival framework for exploring macrohistorical puzzles.

Programmable data acquisition system for research measurements from meteorological radiosondes

A programmable data acquisition system to allow novel use of meteorological radiosondes for atmospheric science measurements is described. In its basic form it supports four analogue inputs at 16 bit resolution, and up to two further inputs at lower resolution configurable instead for digital instruments. It also provides multiple instrument power supplies (+8V, +16V, +5V and -8V) from the 9V radiosonde battery. During a balloon flight encountering air temperatures from +17°C to -66°C, the worst case voltage drift in the 5V unipolar digitisation circuitry was 20mV. The system liberates a new range of low cost atmospheric research measurements, by utilising radiosondes routinely launched internationally for weather forecasting purposes. No additional receiving equipment is required. Comparisons between the specially instrumented and standard meteorological radiosondes show negligible effect of the additional instrumentation on the standard meteorological data.

Incorporating semiotics into fuzzy logic to enhance Clinical Decision Support Systems

In order to enhance the quality of care, healthcare organisations are increasingly resorting to clinical decision support systems (CDSSs), which provide physicians with appropriate health care decisions or recommendations. However, how to explicitly represent the diverse vague medical knowledge and effectively reason in the decision-making process are still problems we are confronted. In this paper, we incorporate semiotics into fuzzy logic to enhance CDSSs with the aim of providing both the abilities of describing medical domain concepts contextually and reasoning with vague knowledge. A semiotically inspired fuzzy CDSSs framework is presented, based on which the vague knowledge representation and reasoning process are demonstrated.

The logic of ideas in Christopher Hill's English revolution

This article examines the role played by ideas and their thinkers in Christopher Hill's histories of the English Revolution. Hill protested against a reductionist economic determinism with no place for the intrinsic power of ideas, but his account of ideas gave them a progressive logic parallel to, if not always easy to link with, that of economic development, and threatened to divorce them from their muddled and imperfect thinkers. This account of the logic of ideas had a striking impact on the way in which the more mainstream radicals of the English Revolution appeared in Hill's work, with both the Levellers and James Harrington being half assimilated to, and half pushed aside in favor of, the more thoroughgoing economic radicals who expressed, in however ragged a way, the intrinsic potential of their ideas. However, Hill's writings also betray a surprising attraction to religious over secular forms of radicalism.