Resistive random access memory (ReRAM) is often considered as a strong candidate for storing the weights in non-von Neumann neuromorphic computing systems. This paper studies how nonideal memory ...characteristics, which include programing error, read fluctuation, and retention, affect the inference accuracy of the analog ReRAM neural networks by incorporating memory characteristics extracted from 1-Mb ReRAM into a simulated inference-only neural network. This paper also shows that the different layer in the network can tolerate different amount of such imperfects. We learned four key points: 1) the conductance range of memory with less relative fluctuation is preferred for designing the weight-conductance mapping; 2) the control of programing error is essential for high inference accuracy; 3) retention-induced conductance drift can be fatal to the neuromorphic system. A compensation scheme is proposed in this paper which can effectively recover the inference accuracy; and 4) for multilayer networks, avoiding weight errors in the front layers can help to maintain the inference accuracy by reducing calculation error which may otherwise accumulate and pass down the networks. The concepts and approaches of this paper can also be applied to evaluate other types of nonvolatile memories for artificial neural networks.
We report an ReRAM-based pseudo-true random number generator (RNG) which can significantly improve the security feature of e-ReRAM chips at a very low cost. Combining the true randomness from ...stochastic behavior of ReRAM and the high output speed from a modified linear feedback shift register (LFSR), the proposed architecture can provide ultrahigh throughput random sequence following system clocks from several Mbit/sec to tens of Gbit/sec. The highly reliable, unpredictable, and unrepeatable ReRAM-based pseudo-true RNG circuit can pass NIST SP800-22 randomness tests at a high score. It is suitable for secure IoT and 5G applications.
In this work, we report two performance enhancement schemes for single-gate vertical-channel (SGVC) 3-D NAND Flash. The first one features a programming (PGM) waveform where the bias of the dummy ...wordline (DWL) is raised in a two-step manner so that the resultant disturbance that the DWL and edge WL suffer is appreciably alleviated. The second scheme takes advantage of a unique behavior termed "self-boosting-enhanced-PGM" mechanism in the pair- bitline PGM method to deal with the slow PGM bits and achieve a much lower bit error rate as a consequence. By using these two approaches, the bit error rate after multilevel cell (MLC) operation can be substantially improved by 82%.
This study examined the association of sleep with inflammation and oxidative stress biomarkers, and with functional outcomes, after stroke rehabilitation. The rehabilitation effects on biomarkers and ...functional outcomes were also evaluated. Twenty subacute stroke survivors received 4 weeks of upper limb rehabilitation. Baseline inflammatory (i.e., soluble intercellular adhesion molecule-1, sICAM-1) and oxidative stress biomarkers (i.e., glutathione peroxidase, GPx and malondialdehyde, MDA) were assessed, as were sleep outcomes. Positive correlations were observed between baseline level of sICAM-1 and number of awakenings at post-treatment (ρ = 0.51, p < 0.05) as well as between baseline level of MDA and post-performance time of the Wolf Motor Function Test (WMFT-time) (ρ = 0.46, p < 0.05). In addition, MDA levels were significantly decreased, and functional outcomes of the modified Rankin Scale (mRS), functional ability scale of the WMFT, and Stroke Impact Scale (SIS-total, and SIS-physical function) were improved after the rehabilitation. This pilot study emphasizes the relationship among biomarkers, sleep, and functional outcomes after stroke rehabilitation. Oxidative stress markers may be useful predictors of functional outcomes in subacute stroke survivors.
Abstract
Background
Joint contractures, which affect activity, participation, and quality of life, are common complications of neurological conditions among elderly residents in long-term care ...facilities. This study examined the reliability and validity of the Chinese version of the PaArticular Scales in a population with joint contractures.
Methods
A cross-sectional study design was used. The sample included elderly residents older than 64 years with joint contractures in an important joint who had lived at one of 12 long-term care facilities in Taiwan for more than 6 months (
N
= 243). The Chinese version of the PaArticular Scales for joint contractures was generated from the English version through five stages: translation, review, back-translation, review by a panel of specialists, and a pretest. Test-retest reliability, internal consistency reliability, construct validity, and criterion validity were evaluated, and the results were compared with those for the World Health Organization Quality of Life scale and the World Health Organization Disability Assessment Schedule.
Results
The Chinese version of the PaArticular Scales had excellent reliability, with a Cronbach α coefficient of 0.975 (mean score, 28.98; standard deviation, 17.34). An exploratory factor analysis showed three factors and one factor with an eigenvalue > 1 that explained 75.176 and 62.83 % of the total variance in the Activity subscale and Participation subscale, respectively. The subscale-to-total scale correlation analysis showed Pearson correlation coefficients of 0.881 for the Activity subscale and 0.843 for the Participation subscale. Pearson’s product-moment correlation revealed that the correlation coefficient (
r
) between the Chinese version of the PaArticular Scales and the World Health Organization Disability Assessment Schedule was 0.770, whereas that for the World Health Organization Quality of Life scale was − 0.553; these values were interpreted as large coefficients.
Conclusions
The underlying theoretical model of the Chinese version of the PaArticular Scales functions well in Taiwan and has acceptable levels of reliability and validity. However, the Chinese version must be further tested for applicability and generalizability in future studies, preferably with a larger sample and in different clinical domains.
Child developmental rate holds predictive value for early-stage developmental trajectories, yet few studies explored how sleep problems during different infancy stages impact this rate. This study ...aims to investigate the correlation between sleep problems and child developmental trajectories.
This study utilized a prospective national cohort of 5006 children in Taiwan. The developmental inventories covering motor, cognitive, language, and socioemotional domains were collected through questionnaire-based in-person home interviews conducted at 3, 12, 24, and 36 months. Sleep problems data, encompassing bedtime regularity, sleep duration, and sleep quality, were collected at 3 and 12 months. Child developmental rate was assessed by analyzing the slope of developmental ability estimates over a period of time.
Bedtime regularity and high-quality sleep at 3 and 12 months were found to be significantly associated with intercepts across all domains (estimate = −0.196∼0.233, p < 0.033). Children with high-quality sleep at 3 months showed enhanced developmental slopes in socioemotional domains (estimate = 0.032, p < 0.001). Atypical sleep duration at 3 and 12 months had differential detrimental association with child development in various domains (estimate = −0.108∼-0.016, p < 0.048).
The relationship between sleep problems and child development exhibited variability based on the timing of exposure to these issues. Early exposure to low-quality sleep was significantly related to developmental functions and socioemotional developmental rate, potentially leading to increased developmental disparities as children age. Inadequate sleep duration in late infancy and excessive sleep duration in early infancy were both negatively associated with child development trajectories. Policymakers can use these findings to design targeted sleep programs for optimal child development.
•The study revealed that sleep problems in different infancy stages can lead to diverse effects on child development.•Notably, exposing infants to low-quality sleep during early infancy could exacerbate developmental gaps in socioemotional domain.•Atypical sleep duration, especially insufficient sleep during late infancy and excessive sleep during early infancy, was negatively associated with child development.•Irregular bedtime and low-quality sleep during infancy were both linked to adverse child developmental functions.•The findings emphasize the importance of addressing sleep problems early on to mitigate potential developmental disparities.
Abstract
A self-reference resistive random-access memory (ReRAM)-based one-transistor, two-ReRAM (1T2R) physically unclonable function (PUF) is proposed to provide a hardware security feature for ...electrical products in the IoT/5G era. There are four advantages from the proposed structure: (1) a small cell size; (2) intrinsic randomness; (3) no programming circuit; and (4) no data retention concerns. The conduction mechanism, temperature dependency, and read fluctuation of the pristine ReRAM device are studied. An information–address separation scheme is proposed which not only reduces the impact of the read noise and the temperature effect, but also improves system integrity against hardware attacks. The proposed 1T2R PUF unit also has great potential for use as a random seed for linear-feedback shift registers in pseudo random number generators with high unpredictability, good randomness, and a high data rate.
Joint contractures and degenerative osteoarthritis are the most common joint diseases in the elderly population, can lead to limited mobility in elderly individuals, can exacerbate symptoms such as ...pain, stiffness, and disability, and can interfere with social participation and quality of life, thus affecting mental health. However, relevant studies on this topic are very limited. This study describes the associations of joint contracture categories and sites in elderly residents in long-term care facilities with their quality of life, activities, and participation.
Elderly individuals with joint contractures who were residents in long-term care facilities were recruited. The World Health Organization (WHO) Quality of Life and the WHO Disability Assessment Schedule 2.0 were used to survey the participants. Correlations, multiple linear regressions, and multiple analyses of variance, with joint contractures as the response variable, were used in the statistical analysis.
The final statistical analysis included 232 participants. The explanatory power of contracture sites on activities and participation had a moderate strength of association (η
= .113). Compared with elderly residents with joint contractures and osteoarthritis isolated to the upper limbs, those with joint contractures and osteoarthritis in both the upper and lower limbs had significantly worse activity and participation limitations. No significant differences in activity and participation were found between elderly residents with joint contractures affecting only the upper limbs and those with joint contractures affecting only the lower limbs (F
= 2.604 and F
= 0.674, nonsignificant). Osteoarthritis had the greatest impact on activity limitations and participation restrictions among elderly residents with joint contractures affecting both the upper and lower limbs (F
= 6.251, p = .014).
Elderly residents in long-term care facilities belonging to minority groups, with a history of stroke, and with osteoarthritis are at a high risk of developing activity limitations and participation restrictions. Moreover, compared with other contraction sites, regardless of osteoarthritis, joint contractures affecting both the upper and lower limbs were associated with the greatest activity limitations and participation restrictions.
This study has been registered in the Chinese Clinical Trial Registry, registration number and date: ChiCTR2000039889 (13/11/2020).
Abstract
We proposed an in-memory spin coupler based on the 55 nm NOR flash technology to tackle the combinatorial optimization problems. The high-density and cost-effective floating-gate (FG) ...devices can overcome the capacity limitation in the conventional annealing machines based on static random access memory. In addition, the FG devices featuring high endurance and excellent data retention provide more robust annealing computation as compared to resistive random access memory. A novel complementary read algorithm is further developed to increase the tolerance on threshold voltage (
V
th
) variation by 60%. Demonstrations show that the proposed in-memory spin coupling architecture with high efficiency and scalability has great potential for solving the combinatorial optimizations regardless of the problem size.
A novel confined nitride (SiN) charge trapping 3-D NAND flash with excellent postcycling retention performances was demonstrated. Using a uniform sidewall lateral recess in the 3-D stack followed by ...a SiN pull-back process to isolate the SiN trapping layer in a self-aligned way is critical to facilitate this structure. Lower erase saturation <; -4 V was shown in the confined SiN cell because of discrete SiN along the Z-direction. Therefore, this structure is in favor of the larger memory window (>10 V) design. Random telegraph noise (RTN) characteristics are comparable to the traditional 3-D NAND device with <; 0.1-V variation. Excellent single-level cell (SLC) retention with only ~600-mV charge loss after 125 °C one-week high-temperature baking for a post-1K-cycled device was obtained. It is far superior to the control sample without a confined SiN structure. Arrhenius analysis at various baking temperatures shows that the retention may pass >100 years at 60 °C and even longer at room temperature. Moreover, superior post-1K-cycled multilevel cell (MLC) retention was also illustrated, which even sustains 150 °C and one-week baking. Therefore, the device has the potential to meet the low-cost long-retention archive memory applications.
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