Strain gauge ambiguity sensor for segmented mirror active optical system

A system is described to measure alignment between interfacing edges of mirror segments positioned to form a segmented mirror surface. It serves as a gauge having a bending beam with four piezoresistive elements coupled across the interfaces of the edges of adjacent mirror segments. The bending beam has a first position corresponding to alignment of the edges of adjacent mirror segments, and it is bendable from the first position in a direction and to a degree dependent upon the relative misalignment between the edges of adjacent mirror segments to correspondingly vary the resistance of the strain guage. A source of power and an amplifier are connected in circuit with the strain gauge whereby the output of the amplifier varies according to the misalignment of the edges of adjacent mirror segments

Children's basic memory processes, stress and maltreatment

Building upon methods and research utilized with normative populations, we examine extant assumptions regarding the effects of child maltreatment on memory. The effects of stress on basic memory processes is examined, and potential neurobiological changes relevant to memory development are examined. The impact of maltreatment-related sequelae (including dissociation and depression) on basic memory processes as well as false memories and suggestibility are also outlined. Although there is a clear need for additional research, the investigations that do exist reveal that maltreated children's basic memory processes are not reliably different from that of other, nonmaltreated children

Understanding Algorithm Performance on an Oversubscribed Scheduling Application

The best performing algorithms for a particular oversubscribed scheduling application, Air Force Satellite Control Network (AFSCN) scheduling, appear to have little in common. Yet, through careful experimentation and modeling of performance in real problem instances, we can relate characteristics of the best algorithms to characteristics of the application. In particular, we find that plateaus dominate the search spaces (thus favoring algorithms that make larger changes to solutions) and that some randomization in exploration is critical to good performance (due to the lack of gradient information on the plateaus). Based on our explanations of algorithm performance, we develop a new algorithm that combines characteristics of the best performers; the new algorithms performance is better than the previous best. We show how hypothesis driven experimentation and search modeling can both explain algorithm performance and motivate the design of a new algorithm

Computer considerations for real time simulation of a generalized rotor model

Scaled equations were developed to meet requirements for real time computer simulation of the rotor system research aircraft. These equations form the basis for consideration of both digital and hybrid mechanization for real time simulation. For all digital simulation estimates of the required speed in terms of equivalent operations per second are developed based on the complexity of the equations and the required intergration frame rates. For both conventional hybrid simulation and hybrid simulation using time-shared analog elements the amount of required equipment is estimated along with a consideration of the dynamic errors. Conventional hybrid mechanization using analog simulation of those rotor equations which involve rotor-spin frequencies (this consititutes the bulk of the equations) requires too much analog equipment. Hybrid simulation using time-sharing techniques for the analog elements appears possible with a reasonable amount of analog equipment. All-digital simulation with affordable general-purpose computers is not possible because of speed limitations, but specially configured digital computers do have the required speed and consitute the recommended approach

Volume-reflecting dielectric heat shield

White, volume-reflecting dielectric material absorbs essentially none of the incident radiant energy, and continues to reflect even though in severe environment its surface is melted and is being vaporized. Process of overall reflectance in dielectric material, involving internal refractions and reflections, is similar to process of reflection in paints

Memory lessons from the courtroom: Reflections on being a memory expert on the witness stand

In the first part of this article, I describe a variety of cases that I have been involved with that led to my becoming an expert witness. These cases range from questions about children’s memory for being raped, to remembering an ear-witnessed murder, to preventing future false memories. In the second part of this article, I reflect on some of the remarkable feats of remembering that complainants exhibit in court, ones that contradict much of what the scientific study of memory has shown to be true. Along the way, I argue that until this scientific knowledge becomes part of a “culture of memory” familiar to triers of fact (judges, jurors), police, and laypeople, memory experts will continue to be an inexorable part of the legal process when memory serves as the main or only evidence

Manipulating Memory Associations Changes Decision-making Preferences in a Preconditioning Task

Memories of past experiences can guide our decisions. Thus, if memories are undermined or distorted, decision making should be affected. Nevertheless, little empirical research has been done to examine the role of memory in reinforcement decision-making . We hypothesized that if memories guide choices in a conditioning decision-making task, then manipulating these memories would result in a change of decision preferences to gain reward. We manipulated participants’ memories by providing false feedback that their memory associations were wrong before they made decisions that could lead them to win money . Participants’ memory ratings decreased significantly after receiving false feedback. More importantly, we found that false feedback led participants’ decision bias to disappear after their memory associations were undermined . Our results suggest that reinforcement decision-making can be altered by fasle feedback on memories . The results are discussed using memory mechanisms such as spreading activation theories

Unravelling the Nature of Early (Autobiographical) Memory

In this article, I provide an overview of the problems associated with understanding the nature of early autobiographical memory and discuss issues concerning the forgetting of these memories (infantile/childhood amnesia). Specifically, I provide a brief exegesis as to whether such memories are stored in a fragile manner to begin with, become difficult to retrieve over time, or both. In order to answer this and other related questions, I review the contribution of the articles in this special issue to understanding the enigma that is infantile/childhood amnesia. I then outline some of the issues that remain and suggest a functional approach to understanding why the forgetting of early experiences may be more adaptive than remembering them. I conclude by suggesting that infantile amnesia may actually begin during infancy itself

D=10 supersymmetric Yang-Mills theory at alpha'^4

The $\alpha'^2$ deformation of D=10 SYM is the natural generalisation of the $F^4$ term in the abelian Born-Infeld theory. It is shown that this deformation can be extended to $\alpha'^4$ in a way which is consistent with supersymmetry. The latter requires the presence of higher-derivative and commutator terms as well as the symmetrised trace of the Born-Infeld $\alpha'^4$ term.Comment: 27 pages. Minor changes to text; references added

Noncommutative symmetric functions and Laplace operators for classical Lie algebras

New systems of Laplace (Casimir) operators for the orthogonal and symplectic Lie algebras are constructed. The operators are expressed in terms of paths in graphs related to matrices formed by the generators of these Lie algebras with the use of some properties of the noncommutative symmetric functions associated with a matrix. The decomposition of the Sklyanin determinant into a product of quasi-determinants play the main role in the construction. Analogous decomposition for the quantum determinant provides an alternative proof of the known construction for the Lie algebra gl(N).Comment: 25 page