12,943 research outputs found
The Fall of Gondolin (2018) by J.R.R. Tolkien, edited by Christopher Tolkien
Book review by Douglas Charles Kane of The Fall of Gondolin (2018) by J.R.R. Tolkien, edited by Christopher Tolkie
Economic evaluation: what does a nurse manager need to know?
This paper considers how health economists can assist nurse managers, using the concepts and tools of economic evaluation. We aim to clarify these and also explode some of the myths about economic evaluation and its role in health care decision-making. Economic evaluation techniques compare alternative courses of action in terms of their costs and consequences. There are four principal methods; cost-minimization, cost-effectiveness, cost-utility and cost-benefit analysis, all of which synthesize costs and outcomes, at different levels of outcome. Economic evaluation is an intrinsic part of national decision-making about the efficient provision of effective treatments and services, and increasingly, organizational matters. In the UK, such technology evaluation is disseminated in guidelines from the National Institute for Clinical Effectiveness (NICE), having a top-down impact on the nurse manager. But economic evaluation is increasingly relevant to the nurse manager at local level, through newer techniques such as Programme Budgeting Marginal Analysis (PBMA), which facilitates explicit, transparent decisions, from the bottom-up. Nurse managers need to weigh up competing demands on resources and decide in ways which maximize health gain. Economic evaluation can help here because it presents evidence to challenge or support existing allocations, and provides a systematic framework to analyse health care decisions. In the current context of competition for scarce resources, we suggest that nurse managers need to embrace these techniques, or be marginalized from the resource allocation process
A continuum of pure states in the Ising model on a halfplane
We study the homogeneous nearest-neighbor Ising ferromagnet on the right half
plane with a Dobrushin type boundary condition --- say plus on the top part of
the boundary and minus on the bottom. For sufficiently low temperature , we
completely characterize the pure (i.e., extremal) Gibbs states, as follows.
There is exactly one for each angle ; here
specifies the asymptotic angle of the interface separating regions
where the spin configuration looks like that of the plus (respectively, minus)
full-plane state. Some of these conclusions are extended all the way to
by developing new Ising exact solution result -- in particular, there
is at least one pure state for each .Comment: In this version, a discussion of the 3D case is include
Experimental economics: Methods, problems and promise
The purpose of this paper is to discuss the growing importance of experimentation in economic analysis. We present a variety of economic issues that have been explored with laboratory techniques. We also address some common objections to experimentation, as well as some of the principal lessons that have been learned.
Experimental Economics
This is the first comprehensive treatment of laboratory experiments designed to evaluate economic propositions under carefully controlled conditions. While it acknowledges that laboratory experiments are no panacea, it argues cogently for their effectiveness in selected situations. Covering methodological and procedural issues as well as theory, Experimental Economics is not only a textbook but also a useful introduction to laboratory methods for professional economists. The emphasis is on organizing and evaluating existing results. The book can be used as an anchoring device for a course at either the graduate or advanced undergraduate level. Applications include financial market experiments, oligopoly price competition, auctions, bargaining, provision of public goods, experimental games, and decision making under uncertainty. The book also contains instructions for a variety of laboratory experiments.laboratory experiments, financial markets, price competition, auctions, bargaining, games, decision making, uncertainty
Parasitism of \u3ci\u3ePlathypena Scabra\u3c/i\u3e (Lepidoptera: Noctuidae) by \u3ci\u3eSinophorus Teratis\u3c/i\u3e (Hymenoptera: Ichneumonidae)
(excerpt)
A study was conducted at the Ecology Research Center, Miami University, Butler County, Ohio, during the summer of 1990 to examine the effects of strip intercropping sorghum and soybean on the occurrence of parasitoids and incidence of disease in larvae ofthe green cloverworm, Plathypena scabra (F.) (Lepidoptera: Noctuidae), a sporadic pest of soybeans. The details of the experimental design and results are reported elsewhere (Williams et al. 1995)
Microgravity robotics technology program
A research program to develop technology for robots operating in the microgravity environment of the space station laboratory is described. These robots must be capable of manipulating payloads without causing them to experience harmful levels of acceleration, and the motion of these robots must not disturb adjacent experiments and operations by transmitting reactions that translate into damaging effects throughout the laboratory. Solutions to these problems, based on both mechanism technology and control strategies, are discussed. Methods are presented for reduction of robot base reactions through the use of redundant degrees of freedom, and the development of smoothly operating roller-driven robot joints for microgravity manipulators is discussed
The dynamic effects of internal robots on Space Station Freedom
Many of the planned experiments of the Space Station Freedom (SSF) will require acceleration levels to be no greater than microgravity (10 exp -6 g) levels for long periods of time. Studies have demonstrated that without adequate control, routine operations may cause disturbances which are large enough to affect on-board experiments. One way to both minimize disturbances and make the SSF more autonomous is to utilize robots instead of astronauts for some operations. The present study addresses the feasibility of using robots for microgravity manipulation. Two methods for minimizing the dynamic disturbances resulting from the robot motions are evaluated. The first method is to use a robot with kinematic redundancy (redundant links). The second method involves the use of a vibration isolation device between the robot and the SSF laboratory module. The results from these methods are presented along with simulations of robots without disturbance control
Reaction-compensation technology for microgravity laboratory robots
Robots operating in the microgravity environment of an orbiting laboratory should be capable of manipulating payloads such that the motion of the robot does not disturb adjacent experiments. The current results of a NASA Lewis Research Center technology program to develop smooth, reaction-compensated manipulation based on both mechanism technology and trajectory planning strategies are present. Experimental validation of methods to reduce robot base reactions through the use of redundant degrees of freedom is discussed. Merits of smooth operation roller-driven robot joints for microgravity manipulators are also reviewed
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