A Plan for the Development of Fusion Energy

This is the final report of a panel set up by the U.S. Department of Energy (DOE) Fusion Energy Sciences Advisory Committee (FESAC) in response to a charge letter dated September 10, 2002 from Dr. Ray Orbach, Director of the DOE's Office of Science. In that letter, Dr. Orbach asked FESAC to develop a plan with the end goal of the start of operation of a demonstration power plant in approximately 35 years. This report, submitted March 5, 2003, presents such a plan, leading to commercial application of fusion energy by mid-century. The plan is derived from the necessary features of a demonstration fusion power plant and from the time scale defined by President Bush. It identifies critical milestones, key decision points, needed major facilities and required budgets. The report also responds to a request from DOE to FESAC to describe what new or upgraded fusion facilities will best serve our purposes over a time frame of the next twenty years.     

Affordance as context

The concept of affordance is relatively easy to define, but has proved to be remarkably difficult to engineer. This paradox has sparked numerous debates as to its true nature. The discussion presented here begins with a review of the use of the term from which emerges evidence for a two-fold classification—simple affordance and complex affordance. Simple affordance corresponds to Gibson's original formulation, while complex affordances embody such things as history and practice. In trying to account for complex affordance, two contrasting, but complementary philosophical treatments are considered. The first of these is Ilyenkov's account of significances which he claims are ‘ideal’ phenomena. Ideal phenomena occupy are objective characteristics of things and are the product of human purposive activity. This makes them objective, but not independent (of any particular mind or perception) hence their similarity to affordances.

The second perspective is Heidegger's phenomenological treatment of ‘familiarity’ and ‘equipment’. As will be seen, Heidegger has argued that familiarity underpins our ability to cope in the world. A world, in turn, which itself comprises the totality of equipment. We cope by making use of equipment. Despite the different philosophical traditions both Ilyenkov and Heidegger have independently concluded that a thing is identified by its use and that use, in turn, is revealed by way of its affordances/significances. Finally, both authors—Heidegger directly and Ilyenkov indirectly—equate context and use, leading to the conclusion that affordance and context are one and the same.     

The construction and performance of a multiviewer 3‐D television display

Abstract— The De Montfort University (DMU) autostereoscopic 3‐D display, intended for television applications, is described. It provides freedom of viewer movement over a typical “living room” sized area, with no restrictions on viewer's head positions. The display is capable of supplying 3‐D images to multiple viewers who do not need to wear special glasses. It operates by producing regions (exit pupils) in the viewing field where either a left or a right image is perceived. The positions of the exit pupils are steered to the viewers' eyes by the use of head tracking. Design issues that became apparent during the construction of a first prototype, and the findings from tests on it, are described. In addition, the current status of a more advanced prototype is reported.     

Factors associated with suicide attempts among patients with schizophrenia

This study explored the association between psychosocial variables and symptoms among patients with schizophrenia-spectrum disorders who have attempted suicide and those who have not attempted suicide. Of 336 patients with a DSM-III-R diagnosis of schizophrenia or schizoaffective disorder who were consecutively evaluated at a university-affiliated clinical research center, 98, or 29.2 percent, reported one or more suicide attempts. Compared with patients who had not attempted suicide, patients who had made an attempt had a greater number of lifetime depressive episodes, an earlier age of onset of their illness, and an earlier age at first hospitalization.     

Collision detection for interactive graphics applications

Collision detection and response are important for interactive graphics applications such as vehicle simulators and virtual reality. Unfortunately, previous collision detection algorithms are too slow for interactive use. The paper presents a new algorithm for rigid or articulated objects that meets performance goals through a form of time critical computing. The algorithm supports progressive refinement, detecting collisions between successively tighter approximations to object surfaces as the application allows it more processing time. The algorithm uses simple four dimensional geometry to approximate motion, and hierarchies of spheres to approximate three dimensional surfaces at multiple resolutions. In a sample application, the algorithm allows interactive performance that is not possible with a good previous algorithm. In particular, the new algorithm provides acceptable accuracy while maintaining a steady and high frame rate, which in some cases improves on the previous algorithm's rate by more than two orders of magnitude     

The (artefactual) remission of reading disability: Psychometric lessons in the study of stability and change in behavioral development.

Patterns of reading disability were examined in 2 longitudinal studies. The major findings were (a) that on the basis of the observed data, remission of reading disability was relatively common with up to 37% of reading-disabled children showing remission of this disability within a 2-year period, and (b) when the data were analyzed with a latent Markov model that took account of measurement errors in test scores, the estimated true rate of remission of reading disability was between 15% and 19% over a 2-year period. The presence of measurement error in reading disability classifications may lead to an inflated and misleading impression of the rate of remission of these problems. General implications of these findings for interpreting patterns of stability and change in longitudinal developmental data were discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Survivability Studies of Lithium Drifted Silicon Detectors under Severe Environmental Conditions

Several lithium drifted silicon, surface barrier detectors were subjected to a variety of environmental conditions. The conditions were primarily those of long term storage under ambient temperature conditions and of long time operation under both ambient and high (+60°C) temperature operation. Use was made of the temperature dependence of the diffusion coefficient of lithium in silicon so that elevated temperatures could be used to decrease the time scale of the tests. Some detectors were also subjected to a series of vibration and shock tests. The entire set of tests was performed in an effort to see if the detectors could withstand the rigors of the Apollo mission. The results of all the tests are given in the paper.     

Inhibition of fat cell lipolysis by low FFA to albumin ratios

Epididymal fat cells isolated from chronically cold-exposed rats were used to study the inhibition of lipolysis with albumin bound FFA. It was demonstrated that lipolysis becomes inhibited as the class 2 binding sites on albumin are filled and that 50% inhibition occurs at free fatty acid (FFA) to albumin ratios between 4.6 and 4.0. Experiments with dibutyryl adenosine cyclic phosphate suggest that this is an effect on the fat cell lipases rather than the lipase activating system or phosphodiesterase. The results indicate that reesterification proceeds as a relatively constant percentage of the rate of lipolysis and, therefore, in the absence of exogenous FFA, conditions that reduce lipolysis reduce reesterification. On the other hand, high rates of reesterification can apparently be stimulated even when the class 1 binding sites on albumin are not filled.