Search results for "Memory"
showing 10 items of 2004 documents
A Low Cost Solution for 2D Memory Access
2006
Many of the new coding tools in the H.264/AVC video coding standard are based on 2D processing resulting in row-wise and column-wise memory accesses starting from arbitrary memory locations. This paper proposes a low cost solution for efficient realization of these 2D block memory accesses on sub-word parallel processors. It is based on the use of simple register-based data permutation networks placed between the processor and memory. The data rearrangement capabilities of the networks can further be extended with more complex control schemes. With the proposed control schemes, the networks enable row and column accesses from arbitrary memory locations for blocks of data while maintaining f…
Dual Information Systems: Supporting Organizational Working and Learning by Making Organizational Memory Transparent
1999
The conceptual design of most computer-based information systems reflects a dualism of technology. During the development phase, part of the work-domain-related knowledge is formalized and encoded in the software, making it difficult for users to reflect on and use this knowledge. This design--use dualism contributes to the deterioration of the interpretive flexibility of information systems. In this article, we outline an information systems architecture called Dual Information Systems (DIS) that incorporates the concepts of an organizational memory information system (OMIS) in a broader framework. DIS help bridge the design--use dualism by providing organizations with a set of services th…
A mixed geometric-systolic approach to parallel molecular dynamics simulations
1995
We have developed a flexible and efficient method of performing molecular dynamics simulations on distributed memory parallel computers. The novel feature is to use simultaneously spatial partitioning and systolic loop approaches according to a strategy which, for a given simulation, adapts itself to the multiprocessor system, allowing to approach optimal performance. The method assures high efficiencies even in situations in which, due to the exceeding large number of processors, the usage of a pure spatial decomposition would be impossible. The algorithm provides as particular cases both the pure spatial partitioning and the pure systolic parallelization schemes, so that its adoption assu…
Principles of scatter search
2006
Scatter search is an evolutionary method that has been successfully applied to hard optimization problems. The fundamental concepts and principles of the method were first proposed in the 1970s, based on formulations dating back to the 1960s for combining decision rules and problem constraints. In contrast to other evolutionary methods like genetic algorithms, scatter search is founded on the premise that systematic designs and methods for creating new solutions afford significant benefits beyond those derived from recourse to randomization. It uses strategies for search diversification and intensification that have proved effective in a variety of optimization problems. This paper provides…
The challenge of forgetting: Neurobiological mechanisms of auditory directed forgetting
2017
Directed forgetting (DF) is considered an adaptive mechanism to cope with unwanted memories. Understanding it is crucial to develop treatments for disorders in which thought control is an issue. With an item-method DF paradigm in an auditory form, the underlying neurocognitive processes that support auditory DF were investigated. Subjects were asked to perform multi-modal encoding of word-stimuli before knowing whether to remember or forget each word. Using functional magnetic resonance imaging, we found that DF is subserved by a right frontal-parietal-cingulate network. Both qualitative and quantitative analyses of the activation of this network show converging evidence suggesting that DF …
Thermal stress affects patch time allocation by preventing forgetting in a parasitoid wasp
2015
Learning and memory allow animals to adjust their foraging strategies through experience. Despite the known impact of temperature on many aspects of the behavioral ecology of animals, memory retention in the face of realistic thermal stress has seldom been assessed. In the laboratory, we studied the behavioral expression of an egg parasitoid’s (Trissolcus basalis) memory when exposed to thermal stress that could be encountered in nature. We hypothesized that thermal stress would disrupt memory consolidation and/ or modify the optimality of memory retention, thus affecting patch time allocation strategies. Memory consolidation was resilient to 1 h of thermal stress following an unrewarded ex…
‘Independence is not given, it is taken’: the Ivorian cinquantenaire and competing history/ies of independence
2013
This article explores competing histories of independence in Cote d'Ivoire. The 2010 commemoration of fifty years of independence led to competing histories about how and if the nation achieved independence in 1960. The postelectoral crisis of 2010–2011 that followed soon afterwards has been interpreted by supporters of the outgoing president Laurent Gbagbo as an attempt by France and the international community to re-colonise Cote d'Ivoire. The article asks how different versions of this history are connected to different political projects and how they have changed through time. The article will analyse these processes of meaning-making in a historiology of Ivorian independence, thus cont…
Use of parallel computing to improve the accuracy of calculated molecular properties
1998
Calculation of electron correlation energy in molecules is unavoidable in accurate studies of chemical reactivity. However, these calculations involve, a computational effort several, even in the simplest cases, orders of magnitude larger than the computer power nowadays available. In this work the possibility of parallelize the calculations of the electron correlation energy is studied. The formalism chosen is the dressing of matrices in both distributed and shared memory parallel systems MIMD. Algorithms developed on PVM are presented, and the results are evaluated on several platforms. These results show that the parallel techniques are useful in order to decrease very appreciably the ti…
ESTUDIO SOBRE EL LENGUAJE Y LAS FUNCIONES EJECUTIVAS DE UN CASO DE SÍNDROME DE X-FRÁGIL
2014
Abstract:STUDY ON LANGUAGE AND EXECUTIVE FUNCTIONS OF A CASE OF FRAGILE X SYNDROMEThe main objective of this study is to compare a subject with a clinical diagnosis of Fragile X Syndrome with other disorders (ADHD, Mental Retardation and ASD) in executive functioning and language. The language variables analyzed are lexical knowledge, lexical access, free induced verbal fluency, comprehension instruction and verbal reasoning. On the other hand, the executive functioning variables evaluated are visual and auditory memory, visual and auditory attention, and visual and auditory planning and inhibition. After evaluation, it is checked that Fragile X Syndrome resembles to Mental Retardation and …
Episodic memories: how do the hippocampus and the entorhinal ring attractors cooperate to create them?
2020
AbstractThe brain is capable of registering a constellation of events, encountered only once, as an episodic memory that can last for a lifetime. As evidenced by the clinical case of the patient HM, memories preserving their episodic nature still depend on the hippocampal formation, several years after being created, while semantic memories are thought to reside in neocortical areas. The neurobiological substrate of one-time learning and life-long storing in the brain, that must exist at the cellular and circuit level, is still undiscovered. The breakthrough is delayed by the fact that studies jointly investigating the rodent hippocampus and entorhinal cortex are mostly targeted at understa…