Common Memory Research Articles

Shape memory response of cellular lattice structures: Unit cell finite element prediction

NiTi, known as Nitinol, is the most common shape memory alloy which offers relatively low modulus of elasticity, shape memory properties, superelastic behavior, biocompatibility and low corrosion rate. In some applications, such as actuators and biomedical implants, it is common to use cellular lattice structure (CLS) to decrease the weight as well as equivalent modulus of elasticity (i.e., stiffness). The focus of this research is to model, at macro scale, the behavior of NiTi CLS (e.g., BCC and BCC-Z) processed through selective laser melting (SLM) additive manufacturing (AM) process. First, BCC and BCC-Z structures were fabricated and subjected to thermomechanical experiment to investigate their shape memory properties. Next, finite element analysis (FEA) was performed using a unit cell model with appropriate boundary conditions. The model is based on a three-dimensional constitutive model derived from the Souza theory. Finally, the stress–strain curves obtained from finite element simulations were compared with those generated from mechanical tests. The comparison showed good agreement between the model predictions and experimental results for BCC (R > 0.98, RMSE = 1.79 MPa, p < 0.05) and BCC-Z (R > 0.97, RMSE = 6.28 MPa, p < 0.05) structures. It was also revealed that the developed model was computationally more efficient than other multi-cell models.

Comparing the confidence calculation rules for forced-choice recognition memory: A winner-takes-all rule wins

Abstract Using a new signal-detection-theory-based approach, Experiments 1 and 2 of this study were found to reveal that the internal confidence for two-alternative forced-choice (2-AFC) recognition memory is calculated in a winner-takes-all manner. The signal strength for one of a pair of stimuli exclusively determines confidence and the other piece of useful information is discarded. Similar winner-takes-all confidence calculation has been reported in different kinds of visual perception tasks, which, together with the present findings, confirms that it is a domain-general metacognitive heuristic. Furthermore, by using a less common 2-AFC recognition memory task to select a new stimulus, Experiment 3 elucidated the underlying mechanism of this confidence calculation heuristic. Previously, it had been assumed that the chosen stimulus’s signal strength selectively determines confidence and that the signal strength for the unchosen stimulus is disregarded (heuristic use of response-congruent evidence or post-decisional confirmation bias). However, the present study demonstrates that the strength of a stronger signal selectively determines confidence and that of a weaker signal is disregarded. That is, the winner in signal competition, not response selection, takes all in the construction of confidence.

Bacterial Memory of Persisters: Bacterial Persister Cells Can Retain Their Phenotype for Days or Weeks After Withdrawal From Colony-Biofilm Culture.

Persister cells, or persisters, are a specific subpopulation of bacterial cells that have acquired temporary antibiotic-resistant phenotypes. In this study, we showed that Escherichia coli produces many more persister cells in colony–biofilm culture than in the usual liquid culture and that these persisters can be maintained in higher numbers than those from liquid culture for up to 4 weeks at 37°C in a fresh, nutrient-rich, antibiotic-containing medium, even after complete withdrawal from the colony–biofilm culture. This suggests the presence of a long-retention effect, or “memory effect”, in the persister cell state of E. coli cells. We also discovered that such increases in persisters during colony–biofilm culture and their memory effects are common, to a greater or lesser degree, in other bacterial species. This is true not only for gram-negative bacteria (Acinetobacter and Salmonella) but also for gram-positive bacteria (Staphylococcus and Bacillus). This is the first report to suggest the presence of a common memory mechanism for the persister cell state, which is inscribed during colony–biofilm culture, in a wide variety of bacteria.

VOLGA BULGARIA HERITAGE AND REGIONAL IDENTITY: THE POLITICS OF MEMORY AND THE “INVENTION” OF TRADITION

The object of the analysis in this article is the social memory of the regional past. Social memory is defined using a constructivist approach. The focus is on the design features of the regional identity through the common memory of the historical past. As part of the study of social memory as a field of representation of images of the past and the actualization of regional identity, the author's sociological study of the sphere of memory of the Bulgarian version of the past of the Republic of Tatarstan was conducted. It is concluded that, in the general direction of the policy of memory of the regional elites, the creation and broadcasting of a certain image of the past based on the appeal to the ancient past allows to construct an ethno-political myth about a strong ancestor with a developed culture and economy and to broadcast the positive characteristics of the ancestor to modern inhabitants of the region and their identity.

Comparing Predictive Accuracy under Long Memory, With an Application to Volatility Forecasting*

This paper extends the popular Diebold-Mariano test to situations when the forecast error loss differential exhibits long memory. It is shown that this situation can arise frequently, since long memory can be transmitted from forecasts and the forecast objective to forecast error loss differentials. The nature of this transmission mainly depends on the (un)biasedness of the forecasts and whether the involved series share common long memory. Further results show that the conventional Diebold-Mariano test is invalidated under these circumstances. Robust statistics based on a memory and autocorrelation consistent estimator and an extended fixed-bandwidth approach are considered. The subsequent Monte Carlo study provides a novel comparison of these robust statistics. As empirical applications, we conduct forecast comparison tests for the realized volatility of the Standard and Poors 500 index among recent extensions of the heterogeneous autoregressive model. While we find that forecasts improve significantly if jumps in the log-price process are considered separately from continuous components, improvements achieved by the inclusion of implied volatility turn out to be insignificant in most situations.

IN THE SEARCHES FOR THE NATIONAL IDENTITY: VISION OF J. BARNES

In this article J. Barnes’s novel «England, England» is analyzed in the aspect of problematization and artistic representation of the individual and national identity question; the originality of author’s interpretation of the identity problem through the metaphor «the invention of tradition» is emphasized; humanistic nature of English writer’s artistic reflection is stressed.National identity problems, national history and memory, national traditions and heritage became «a significant trend» of the modern British artistic literature, and J. Barnes’s art is one of many bright proofs of this, because of the serious intention to understanding of what we call «Englishness» is demonstrated in his works.Novel «England, England» (1988) is the concentration of author’s reflections on the question about national identity. He decided to share these questions with his nationals and not only, proclaiming that «England, England is a letter to my own country at the turn of the millennium». Due to Barnes, he focuses on what can be called «the invention of tradition» in this novel, and he admires the idea of expanding of this metaphor in the context of E. Renan’s thesis «getting its history wrong is part of becoming a nation». Testing the power of national historical memory and national past and heritage, consequently ruining national consciousness stereotypes and demythologizing important «Englishness» significators, Barnes points out the crisis state of the modern world, which is able to find neither its real history nor identity.Metaphor, that was given in the beginning of the novel and that tells us about the attempt of the protagonist to find herself through memories of her own childhood, when she was doing puzzles with English counties, is the analogy to finding by country the national identity, which is also lost in the blurred reminiscences. This way Barnеs con vinces, that the past of a human being is strongly correlated with country’s existence history. In the novel individual and common memory are deeply interconnected together with each other.Forming our imagination about identity as unreachable utopia by text’s logic, the author also doubts about certainty commonly used «Englishness» signs, underlining impossibility of reproduction of authentic version of national or individual identity. Barnes insists on objective «uncertainty of being» (D. Zatonskij) and talks to readers with the help of steady humanistic values. Person and country live through the similar processes during their life, the loss of faith in reality of normal life basis equals to the loss of sense of being, people and nation, that do not know their history are doomed to wandering in the stormy life ocean. However, they find sense of being, if they have a strong rod and if they dive into wide contexts of truly existing life, when their faith in something more serious and meaningful is only one thing that is left, instead of intermediate modern state and personal ’ego’. Terms of reference, that the protagonist Marta reaches, saturate writer’s prose with universal, humanistic reflections. They one more time point out versatility and philosophical complexity of the modern British novel.

“It’s a War I Still Would Go To”: The American War in Vietnam and Nostalgic Re-Imaginings of World War II

In this article, I trace the process through which World War II (WWII) has become the „good war” in American culture. Drawing on a range of books and articles published on the subject —and often written by the war’s veterans—I summarize their findings considering the essentially mythical nature of the conflict’ common memory. The well-known aspects of this myth include the view that WWII was a straightforward struggle between good and evil, that the U.S. soldiers who fought it belonged to “the greatest generation,” and that it was ultimately an expression and activization of American honor, heroism, and gallantry. Further on, I argue that beginning in the 1980s, a resurgence of cultural interest in WWII becomes evident, but now tinged not only with the emerging image of “the good war,” but also with nostalgia—and that the “nostalgization” of the conflict was caused directly by, and indeed possible only because of, the U.S. experience in Vietnam. I trace the multifaceted and multiple references to WWII in Vietnam War narratives—but also to Vietnam in some nostalgic representations of WWII.

THE ANALYSIS OF SEMIOTICS OF THE FAMILY LANGUAGE AS A VERBALIZED AREA OF FAMILY DISCOURSE

The article deals with the discursive symbolism of elements of the language system which determines the specificity of family discourse semiotics. The symbolism of the „family" sign is predetermined by the case-interpretation. Family language is a set of secondary symbols created by a group and associated with emotional rituals. Integration of family language sign in the area of their functioning – family discourse – is based on the mutual determinism. From the perspective of Charles Peirce’s theory of sign (classifying into three main trychotomies – the sign by itself, the meaning of the sign and its syntagmatic functioning in interaction with others), the research shows the whole complex of characteristics of semiotic entities in intra-familial nominations. The article proves that the "family" precedent is based on the experience within a collective cognitive space – common (recognizable, used and cited by other members of the group – family) memories that determine the identity of a man as a representative of the family recognizing its values, norms, ideas, priorities, tastes and traditions. Family images as archetype and culturally socialized symbols, are the "messengers" of ancient times, and, correlating with contemporary cultural context, are transformed under its influence. The family discourse symbolic meanings are genuinely represented by a set of specific nominative acts

Examination of long-term visual memorization capacity in the Clark's nutcracker (Nucifraga columbiana).

Clark's nutcrackers exhibit remarkable cache recovery behavior, remembering thousands of seed locations over the winter. No direct laboratory test of their visual memory capacity, however, has yet been performed. Here, two nutcrackers were tested in an operant procedure used to measure different species' visual memory capacities. The nutcrackers were incrementally tested with an ever-expanding pool of pictorial stimuli in a two-alternative discrimination task. Each picture was randomly assigned to either a right or a left choice response, forcing the nutcrackers to memorize each picture-response association. The nutcrackers' visual memorization capacity was estimated at a little over 500 pictures, and the testing suggested effects of primacy, recency, and memory decay over time. The size of this long-term visual memory was less than the approximately 800-picture capacity established for pigeons. These results support the hypothesis that nutcrackers' spatial memory is a specialized adaptation tied to their natural history of food-caching and recovery, and not to a larger long-term, general memory capacity. Furthermore, despite millennia of separate and divergent evolution, the mechanisms of visual information retention seem to reflect common memory systems of differing capacities across the different species tested in this design.

Experimental Evaluation of Agent-based Approaches to Solving Multi-mode Resource-Constrained Project Scheduling Problem

ABSTRACTIn this paper, a rank-based nonparametric statistical test for measuring the effect of cooperation between optimization agents solving the multi-mode resource-constrained project scheduling problem is presented. To solve this NP-hard optimization problem, different methods are applied including population- and agent-based approaches. One of them is a team of asynchronous agents composed of multiple optimization agents, management agents, and common memories, which through interactions produce solutions of hard optimization problems. Optimization agents represent different methods including local search, path relinking, or tabu search. Interactions are managed through various cooperation strategies based on applying heuristics, reinforcement learning, or population learning.

Leveraging older adults' susceptibility to distraction to improve memory for face-name associations.

Forgetting people's names is a common memory complaint among older adults and one that is consistent with experimental evidence of age-related decline in memory for face-name associations. Despite this difficulty intentionally forming face-name associations, a recent study demonstrated that older adults hyperbind distracting names and attended faces, which produces better learning of these face-name pairs when they reappear on a memory test (Weeks, Biss, Murphy, & Hasher, 2016). The current study explored whether this effect could be leveraged as an intervention to reduce older adults' forgetting of face-name associations, using a method previously shown to improve older adults' retention of a word list (Biss, Ngo, Hasher, Campbell, & Rowe, 2013). Twenty-five younger and 32 older adults studied 24 face-name pairs and were tested via immediate and delayed memory tests. During the 30-min retention interval, 10 of the face-name pairs reoccurred as distraction in an ostensibly unrelated face-judgment task, providing an opportunity to implicitly rehearse these pairs. Older adults showed reduced forgetting of repeated face-name pairs as well as improved recollection. Younger adults showed no reliable benefit. These findings indicate that useful distraction benefits older adults' memory for face-name associations, suggesting its potential utility as a memory intervention technique. (PsycINFO Database Record

Efficient LDPC Code Design for Combating Asymmetric Errors in STT-RAM

Spin-transfer torque random access memory (STT-RAM) is a promising emerging memory technology in the future memory hierarchy. However, its unique reliability challenges, i.e., the asymmetric bit failure mechanism at different bit flippings, have raised significant concerns in its real applications. Recent studies even show that the common memory error repair “remedies” cannot efficiently address them. In this article, we for the first time systematically study the potentials of the strong low-density parity-check (LDPC) code for combating such unique asymmetric errors in both single-level-cell (SLC) and multi-level-cell (MLC) STT-RAM designs. A generic STT-RAM channel model suitable for the SLC/MLC designs, is developed to analytically calibrate all the accumulated asymmetric factors of the write/read operations. The key initial information for LDPC decoding, namely asymmetric log-likelihood ratio (A-LLR), is redesigned and extracted from the proposed channel model, to unleash the LDPC’s asymmetric error correcting capability. LDPC codec is also carefully designed to lower the hardware cost by leveraging the systematic-structured parity check matrix. Then two customized short-length LDPC codes—(585,512) and (683,512)—augmented from the semi-random parity check matrix and the A-LLR based asymmetric decoding, are proposed for SLC and MLC STT-RAM designs, respectively. Experiments show that our proposed LDPC designs can improve the STT-RAM reliability by at least 10 2 (10 4 ) when compared to the existing error correction codes (ECCs) for the SLC (MLC) design, demonstrating the feasibility of LDPC solutions on STT-RAM.

Building a lieu de memoire in Romanian Consciousness: From Sorin Ilieşiu's Documentary "Queen Marie-The Last Romantic, the First Modern Woman" to the Golden Room in Pelişor Castle

In 2018 Romania will celebrate the centenary of the Union of 1918, or the Great Union, when all Romanian provinces united into one state: Great Romania, a national ideal which Romanians strove for and achieved on the battlefield and which the Trianon Treaty of 1920 confirmed. For such a time as this hundredth anniversary, it is only natural to call to mind people who made this ideal come true. Queen Marie is rightly considered one of the artisans of the Great Union, being regarded at the time and afterwards as “the living consciousness of Romanian unity, the symbol of confidence in final victory” (Boia 2001: 208). This article aims to investigate the manner in which the queen’s memory is kept alive, and draws on two distinct attempts to portray the queen: Sorin Ilieşiu’s documentary Queen Marie – The Last Romantic, the First Modern Woman and the Golden Room in Pelişor Castle, Queen Marie’s official residence in Sinaia, the royal resort in the Carpathians. These two attempts illustrate how present-day Romanian society tries to regain parts of a common memory that was purposefully obliterated by the communist regime, and strives to rediscover and remap places of their shared memory. My analysis of Ilieşiu’s portrayal of the queen is circumscribed to the field of social semiotics, mainly to the concepts of “distance”, “angle” and “gaze” which Theo van Leeuwen uses in the visual representation of social actors. In my investigation of memory remapping, I draw on Pierre Nora’s concept “lieu de mémoire” and aim to prove that the Golden Room in Pelişor Castle, a place that reflects the personality of the chatelaine and where the queen symbolically reconnected with her origins, has turned into a realm where Romanians have access to a part of their memory which communism did its best to extirpate.

Libreta: Computerized Optimization and Code Synthesis for Electron Repulsion Integral Evaluation.

A new library called libreta for the evaluation of electron repulsion integrals (ERIs) over segmented and contracted Gaussian functions is developed. Our libreta is optimized from three aspects: (1) The Obara-Saika, Dupuis-Rys-King, and McMurchie-Davidson method are all employed. The recurrence relations involved are optimized by tree-search for each combination of angular momenta, and in the best case, 50% of the intermediates can be eliminated to reduce the computational cost. (2) The optimized codes for recurrence relations are combined with different contraction orders, each of which is suitable for ERIs of different angular momenta and contraction patterns. In practice, libreta will determine and use the best scheme to evaluate each ERI. (3) libreta is also optimized at the coding level. For example, with common subexpression elimination and local memory access, the performance can be increased by about 6% and 20%, respectively. The performance was compared with libint2. For both popular segmented and contracted basis sets, libreta can be faster than libint2 by 7.2-912.0%. For basis sets of heavy elements that contain Gaussian basis functions of large contraction degrees, the performance can be increased 20-30 times. We also tested the performance of libreta in direct self-consistent field (SCF) calculations and compared it with NWChem. In most cases, the average time for one SCF iteration by libreta is less than NWChem by 144.2-495.9%. Finally, we discuss the origin of redundancies occurring in the recurrence relations and derive an upper bound of the least number of intermediates required to be calculated in a McMurchie-Davidson recurrence, which is confirmed by ours as well as previous authors' results. We expect that libreta can become a useful tool for theoretical and computational chemists to develop their own algorithms rapidly.

Saliva Biomarkers May Predict How Long Concussion Symptoms Will Last in Youth

Saliva Biomarkers May Predict How Long Concussion Symptoms Will Last in Youth

INTEGRATION OF ARTIFICIAL NEURAL NETWORKS AND KNOWLEDGE BASES

This article reviews the questions and directions of integration of artificial neural networks with knowledge bases. Two main directions of integration are considered: the inputs and outputs of artificial neural network to use integration of knowledge bases and artificial neural networks for solutions of application problems; by artificial neural network representation on the basis of ontological structures and its interpretation by means of knowledge processing in the knowledge base providing an intelligent environment for the development, training and integration of different artificial neural networks compatible with knowledge bases. The knowledge bases that are integrated with artificial neural networks are built on the basis of homogeneous semantic networks and multiagent approach to represent and process knowledge. An ontological model for representing artificial neural networks and their specifications within the framework of the model of unified semantic representation of knowledge is proposed. It is distinguished by the ability to represent artificial neural networks, its dynamics and other types of knowledge, including the specifications of artificial neural networks, as the common language for the representation of knowledge with a common theoreticalmodel semantics. A multiagent model for solving problems using artificial neural networks and other types of knowledge is proposed. It is distinguished by the interaction of agents in accordance with a given temporal model through a common memory that stores knowledge integrated into a single knowledge base.

An Efficient Algorithm for Load Balancing in Multiprocessor Systems

A multiprocessor system is a computer with two or more central processing units (CPUs) with each one sharing the common main memory as well as the peripherals. Multiprocessor system is either homogeneous or heterogeneous system. A homogeneous system is a cluster of processors joined to a high speed network for accomplishing the required task; also it is defined as parallel computing system. Homogeneous is a technique of parallel computing system. A heterogeneous system can be defined as the interconnection of a number of processors, having dissimilar computational speed. Load balance is a method of distributing work between the processors fairly in order to get optimal response time, resource utilization, and throughput. Load balancing is either static or dynamic. In static load balancing, work is distributed among all processors before the execution of the algorithm. In dynamic load balancing, work is distributed among all processors during execution of the algorithm. So problems arise when it cannot statistically divide the tasks among the processors. To use multiprocessor systems efficiently, several load balancing algorithms have been adopted widely. This paper proposes an efficient load balance algorithm which addresses common overheads that may decrease the efficiency of a multiprocessor system. Such overheads are synchronization, data communication, response time, and throughput.

Базовые библиотеки линейной алгебры для высокопроизводительных расчетов

The article considers linear algebra libraries such as BLAS, LAPACK, ScaLAPACK, MKL, and ATLAS, which support high-performance computing (HPC) in modern architectures and are used both in well-known performance tests and in various applications. In the majority of applications, the most time-consuming computation stages are implemented by calling subroutines from such libraries; therefore, the optimal choice of a library is an important issue in setting up computations. The main aim of this review is to describe the invariant characteristics of libraries to achieve high performance of applications. High performance computations used in different fields of knowledge are briefly reviewed. Classification of linear algebra libraries in terms of their functionality and applied high-performance architectures is suggested. The basic low-level BLAS library implemented for all HPC architectures is demonstrated. It is pointed out that the BLAS library supports dividing of the entire computation process into several parallel flows in systems with a common memory field; for such systems, tools such as OpenMP or OpenACC are used. In the case of systems with distributed memory, the parallel version of this library, called PBLAS is used, which supports exchange of messages between nodes using the MPI standard. Higher-level libraries based on the BLAS, e.g., the LAPACK library, which contains a large set of different programs for linear algebra, are described. The ScaLAPACK library for the distributed memory model, which is based on the LAPACK and PBLAS libraries, as well as the Intel MKL library, which is its modern development, are presented. To support efficient operation of hybrid systems, the fundamentally new libraries MAGMA and PLASMA involving features for optimizing linear-algebraic computing of small dimension are analyzed. Libraries supporting solution of eigenvalue problems, such as the EISPACK, PeigS, and a number of other libraries, are investigated. It is pointed out that in the new ELPA library oriented to supercomputers, both OpenMP and MPI tools can be used. It is noted that operations on sparse matrices, especially multiplication of matrices, are very relevant for many applied fields of science; in this regard, the SparseBLAS library can be considered to be the basic standard for them. It is concluded that the optimal choice of a library depends essentially on both the particular application and on the used computing architecture.

GVF snake algorithm-a parallel approach

Multicore architecture is an emerging computer technology where multiple processing element will be acting as independent processing cores by sharing a common memory. Digital image segmentation is a widely used medical imaging application to extract regions of interest. GVF Active Contour is a region based segmentation technique which extracts curved and irregular shaped regions by diffusing gradient vectors and by the influence of internal and external forces. This requires prior knowledge on the geometric position and anatomical structures to locate the specific region defined within an image domain. This process requires complex mathematical calculations which in turn results in the immense consumption of CPU processing time. This may adversely affect the overall performance efficiency of the process. With the advancements in multicore technology, this processing time delay can be reduced by adapting parallelization in the computation of GVF field to the specific region of interest which is to be segmented. OpenMP is a shared memory parallel programming construct, which could implement multicore parallelism with extensive and powerful APIs thereby supporting the functionalities required to attain parallelism. This article provides a high level overview of OpenMP, its effectiveness and ease of implementation in adapting parallelism to existing traditional sequential methods using instruction, data and loop level parallelism. Performance comparison could be done with sequential versions of the program written in Matlab, Java and C languages with the proposed parallelized version of OpenMP. The result is also comparable with different operating systems like Windows and Linux.

Trauma I wojny światowej (shell shock) w poezji brytyjskich żołnierzy oraz w modernistycznej prozie kobiecej

First World War shell shock in British poetry of soldier-poets and modernist prose of women writers The purpose of the following article is to compare and contrast the literary modes of representation of the First World War shell shock in the poetry of soldier-poets and in the prose of women writers. The war trauma called “shell shock” had a profound impact on British literature and the common memory of the Great World. At the time, the poets who were soldiers expressed their traumatic experiences in their works. Meanwhile, women authors who observed veterans suffering from trauma explored the causes and effects of shell shock in their prose.Keywords: trauma; shell shock; war; soldier;