Memory Performance Optimization of DTN Relay Node Based on M/G/1

ABSTRACTWe present a detailed study of memory performance of titanium oxide (TiO2-x)-based resistive switching memories by modifying critical parameters of the films involved in the memory stack grown by reactive sputtering at room temperature. The device includes a Ti nanolayer at the Au/TiO2-x interface and it is defined by the following material stack: Au/Ti/TiO2-x/Au/SiO2/Si. We investigate the memory performance optimization of the device in terms of the Ti nanolayer thickness using as a starting point for the TiO2-x growth conditions these identified by varying the ratio of oxygen concentration to argon concentration by our previous results. Due to the superb ability of Ti to absorb oxygen atoms from the dielectric matrix, a large amount of oxygen vacancies is created, which are crucial for the stable function of the memory devices. We observe the existence of an optimum Ti thickness that if further increased gradually degrades the resistive switching behavior. The induced interface oxide thickness is found also to affect the fluctuation of the ON/OFF processes. In terms of electrical performance self-rectifying characteristics were recorded for all samples in the both resistance states. We then demonstrate that at least five-level resistance states could be obtained by modifying the compliance current, exhibiting excellent resistance uniformity and retention capability. The results are supported by C-AFM measurements demonstrating the scaling potential of the large area device discussed above.

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Memory Performance Optimization

2020 IEEE/ACM 10th Workshop on Irregular Applications: Architectures and Algorithms (IA3) ◽

10.1109/ia351965.2020.00016 ◽

2020 ◽

Author(s):

Nuwan Jayasena

Keyword(s):

Performance Optimization ◽

Memory Performance

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The NICAM 3.5km-1024 ensemble simulation: Performance optimization and scalability of NICAM-LETKF on supercomputer Fugaku

10.5194/egusphere-egu21-4771 ◽

2021 ◽

Author(s):

Hisashi Yashiro ◽

Koji Terasaki ◽

Yuta Kawai ◽

Shuhei Kudo ◽

Takemasa Miyoshi ◽

...

Keyword(s):

Performance Optimization ◽

Data Transfer ◽

Memory Performance ◽

Atmospheric Model ◽

Data Layout ◽

Performance Measurements ◽

Ensemble Simulation ◽

Simulation Performance ◽

Trade Offs ◽

Effective Performance

<p>In parallel with the new Japanese flagship supercomputer, Fugaku, we have continued improving a nonhydrostatic icosahedral atmospheric model (NICAM). Here, we introduce the results of our system-application co-design since 2014. Fugaku's CPU (A64FX) is based on the Arm instruction-set architecture. This 48-core many-core CPU is equipped with 32GB of HBM2 memory, showing data transfer performance comparable to GPUs. We have implemented kernel-level optimizations to take advantage of Fugaku's high memory performance. Among them, we recognized trade-offs related to ensuring memory locality and parallelism, and register allocation. We improved the application's average arithmetic intensity through detailed loop-by-loop performance measurements and reduced memory pressure by actively using single-precision operations. We also redesigned the data layout and the file I/O component of the ensemble data assimilation (DA) system and achieved good scalability in the atmospheric simulation and DA. We performed a global 3.5km mesh, 1024-member ensemble simulation, and DA using 82% of the Fugaku system (131,072 nodes, 6,291,456 cores). In this world's most massive ensemble DA benchmark experiment, the simulation and the DA achieved 29 PFLOPS and 79 PFLOPS of effective performance.</p>

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Impact of Comorbid Depression on Serial Position Effects in Alzheimer’s Disease

GeroPsych ◽

10.1024/1662-9647/a000115 ◽

2014 ◽

Vol 27 (4) ◽

pp. 161-169 ◽

Cited By ~ 1

Author(s):

Nienke A. Hofrichter ◽

Sandra Dick ◽

Thomas G. Riemer ◽

Carsten Schleussner ◽

Monique Goerke ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Serial Position ◽

Episodic Memory ◽

Memory Performance ◽

Memory Function ◽

Word List ◽

Position Effects ◽

Serial Position Effects ◽

List Memory

Hippocampal dysfunction and deficits in episodic memory have been reported for both Alzheimer’s disease (AD) and major depressive disorder (MDD). Primacy performance has been associated with hippocampus-dependent episodic memory, while recency may reflect working memory performance. In this study, serial position profiles were examined in a total of 73 patients with MDD, AD, both AD and MDD, and healthy controls (HC) by means of CERAD-NP word list memory. Primacy performance was most impaired in AD with comorbid MDD, followed by AD, MDD, and HC. Recency performance, on the other hand, was comparable across groups. These findings indicate that primacy in AD is impaired in the presence of comorbid MDD, suggesting additive performance decrements in this specific episodic memory function.

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Neural Encoding Correlates of High and Low Verbal Memory Performance

Journal of Psychophysiology ◽

10.1027/0269-8803.20.2.68 ◽

2006 ◽

Vol 20 (2) ◽

pp. 68-78 ◽

Cited By ~ 7

Author(s):

Sibylle Heinze ◽

Gudrun Sartory ◽

Bernhard W. Müller ◽

Armin de Greiff ◽

Michael Forsting ◽

...

Keyword(s):

Verbal Memory ◽

Parietal Lobe ◽

Functional Neuroimaging ◽

Memory Performance ◽

Extrastriate Cortex ◽

Parahippocampal Gyrus ◽

Premotor Area ◽

High Performers ◽

Rehearsal Strategy ◽

Common Memory

Neuroimaging studies have indicated involvement of left prefrontal cortex and temporal areas in verbal memory processes. The current study used event-related functional neuroimaging to compare encoding of subsequently recalled and not recalled words in high and low memory performers. Fifteen healthy volunteers were given lists of words to learn with immediate recall and to read as a control condition. High performers reported to have visualized the words whereas low performers used a rehearsal strategy. Compared to reading, unsuccessful encoding was associated with thalamic and left premotor area (BA 6) activity. Comparing successful with unsuccessful learning yielded widespread activity of the left prefrontal and posterior temporal gyrus as well as the left superior parietal lobe in the whole group. Low performers showed activation of the left premotor area throughout learning and additionally of the left middle temporal and parahippocampal gyrus during successful encoding. High performers showed increased activation in the extrastriate cortex throughout learning and additionally in the left parietal post- and paracentral areas as well as in the right precuneus during successful encoding. The results suggest that high verbal memory performance is the result of spatiovisual activation concomitant to imagery and low performance of hippocampal and motor activation, the latter being associated with rehearsal, with a common memory circuit subserving both groups.

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Learning and Consolidation of Verbal Declarative Memory in Patients with Posttraumatic Stress Disorder

Zeitschrift für Psychologie / Journal of Psychology ◽

10.1027/0044-3409/a000020 ◽

2010 ◽

Vol 218 (2) ◽

pp. 135-140 ◽

Cited By ~ 1

Author(s):

Slawomira J. Diener ◽

Herta Flor ◽

Michèle Wessa

Keyword(s):

Posttraumatic Stress Disorder ◽

Posttraumatic Stress ◽

Verbal Memory ◽

Stress Disorder ◽

Declarative Memory ◽

Memory Performance ◽

Verbal Learning ◽

Depression Scale ◽

Learning Performance ◽

Ptsd Symptoms

Impairments in declarative memory have been reported in posttraumatic stress disorder (PTSD). Fragmentation of explicit trauma-related memory has been assumed to impede the formation of a coherent memorization of the traumatic event and the integration into autobiographic memory. Together with a strong non-declarative memory that connects trauma reminders with a fear response the impairment in declarative memory is thought to be involved in the maintenance of PTSD symptoms. Fourteen PTSD patients, 14 traumatized subjects without PTSD, and 13 non-traumatized healthy controls (HC) were tested with the California Verbal Learning Test (CVLT) to assess verbal declarative memory. PTSD symptoms were assessed with the Clinician Administered PTSD Scale and depression with the Center of Epidemiological Studies Depression Scale. Several indices of the CVLT pointed to an impairment in declarative memory performance in PTSD, but not in traumatized persons without PTSD or HC. No group differences were observed if recall of memory after a time delay was set in relation to initial learning performance. In the PTSD group verbal memory performance correlated significantly with hyperarousal symptoms, after concentration difficulties were accounted for. The present study confirmed previous reports of declarative verbal memory deficits in PTSD. Extending previous results, we propose that learning rather than memory consolidation is impaired in PTSD patients. Furthermore, arousal symptoms may interfere with successful memory formation in PTSD.

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The Relationship Between Interoception and Metacognition

Journal of Psychophysiology ◽

10.1027/0269-8803/a000157 ◽

2016 ◽

Vol 30 (2) ◽

pp. 76-86 ◽

Cited By ~ 10

Author(s):

Judith Meessen ◽

Verena Mainz ◽

Siegfried Gauggel ◽

Eftychia Volz-Sidiropoulou ◽

Stefan Sütterlin ◽

...

Keyword(s):

Memory Performance ◽

Memory Task ◽

Demographic Characteristics ◽

Metacognitive Awareness ◽

Interoceptive Awareness ◽

Future Research ◽

Heartbeat Perception ◽

Interoceptive Accuracy ◽

The Relationship

Abstract. Recently, Garfinkel and Critchley (2013) proposed to distinguish between three facets of interoception: interoceptive sensibility, interoceptive accuracy, and interoceptive awareness. This pilot study investigated how these facets interrelate to each other and whether interoceptive awareness is related to the metacognitive awareness of memory performance. A sample of 24 healthy students completed a heartbeat perception task (HPT) and a memory task. Judgments of confidence were requested for each task. Participants filled in questionnaires assessing interoceptive sensibility, depression, anxiety, and socio-demographic characteristics. The three facets of interoception were found to be uncorrelated and interoceptive awareness was not related to metacognitive awareness of memory performance. Whereas memory performance was significantly related to metamemory awareness, interoceptive accuracy (HPT) and interoceptive awareness were not correlated. Results suggest that future research on interoception should assess all facets of interoception in order to capture the multifaceted quality of the construct.

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