67 research outputs found
swTVM: Exploring the Automated Compilation for Deep Learning on Sunway Architecture
The flourish of deep learning frameworks and hardware platforms has been
demanding an efficient compiler that can shield the diversity in both software
and hardware in order to provide application portability. Among the exiting
deep learning compilers, TVM is well known for its efficiency in code
generation and optimization across diverse hardware devices. In the meanwhile,
the Sunway many-core processor renders itself as a competitive candidate for
its attractive computational power in both scientific and deep learning
applications. This paper combines the trends in these two directions.
Specifically, we propose swTVM that extends the original TVM to support
ahead-of-time compilation for architecture requiring cross-compilation such as
Sunway. In addition, we leverage the architecture features during the
compilation such as core group for massive parallelism, DMA for high bandwidth
memory transfer and local device memory for data locality, in order to generate
efficient code for deep learning application on Sunway. The experimental
results show the ability of swTVM to automatically generate code for various
deep neural network models on Sunway. The performance of automatically
generated code for AlexNet and VGG-19 by swTVM achieves 6.71x and 2.45x speedup
on average than hand-optimized OpenACC implementations on convolution and fully
connected layers respectively. This work is the first attempt from the compiler
perspective to bridge the gap of deep learning and high performance
architecture particularly with productivity and efficiency in mind. We would
like to open source the implementation so that more people can embrace the
power of deep learning compiler and Sunway many-core processor
Distribution and speciation of dissolved iron in Jiaozhou Bay (Yellow Sea, China)
The distribution of total dissolved iron (DFe) and its chemical speciation were studied in vertical profiles of the shallow and semi-closed Jiaozhou Bay (JZB, China) during two contrasting periods: summer (July 19th, 2011) and spring (May 10th, 2012). Samples collected from the surface, middle and bottom layers were analyzed by competitive ligand exchange-adsorptive cathodic stripping voltammetry (CLE-aCSV). The mean DFe concentration during the summer period (median 18.8 nM ; average 20.7 nM) was higher than in the spring period (median 12.4 nM ; average 16.9 nM), whereas the spatio-temporal variation in spring was larger than in summer. The DFe-values showed distinct regional and seasonal differences, ranging from 5.6 to 107 nM in spring period and 13.4 to 43.4 nM in summer period. In spring, the highest DFe-values were observed in the eastern coastal region, especially near an industrial area (up to 107 nM), whereas the DFe distribution in summer was relatively even. Due to a tide influence, the vertical variations in the DFe and Lt in both seasons were not significant. On average, the Lt concentration (one class of ligand was estimated in all samples), was higher in spring (35.2 ± 23.4 nM) than in summer (31.1 ± 10.3 nM). A statistically significant correlation was found between Lt and DFe concentrations, it was higher for the summer period than for the spring period. The conditional stability constants (logK′) of organic complexes with iron were weaker in spring (11.7 ± 0.3) than in summer (12.3 ± 0.3). The concentrations of Lt were higher in comparison to DFe in all samples: the average [Lt]/[DFe] ratio in the spring and summer samples was 2.4 and 1.5, respectively. Speciation calculations showed that the DFe in the JZB existed predominantly (over 99.99%) in the form of strong organic complexes in both seasons
Dielectric relaxation, resonance and scaling behaviors in Sr3Co2Fe24O41 hexaferrite
The dielectric properties of Z-type hexaferrite Sr(3)Co(2)Fe(24)O(41) (SCFO) have been investigated as a function of temperature from 153 to 503 K between 1 and 2 GHz. The dielectric responses of SCFO are found to be frequency dependent and thermally activated. The relaxation-type dielectric behavior is observed to be dominating in the low frequency region and resonance-type dielectric behavior is found to be dominating above 10(8) Hz. This frequency dependence of dielectric behavior is explained by the damped harmonic oscillator model with temperature dependent coefficients. The imaginary part of impedance (Z″) and modulus (M″) spectra show that there is a distribution of relaxation times. The scaling behaviors of Z″ and M″ spectra further suggest that the distribution of relaxation times is temperature independent at low frequencies. The dielectric loss spectra at different temperatures have not shown a scaling behavior above 10(8) Hz. A comparison between the Z″ and the M″ spectra indicates that the short-range charges motion dominates at low temperatures and the long-range charges motion dominates at high temperatures. The above results indicate that the dielectric dispersion mechanism in SCFO is temperature independent at low frequencies and temperature dependent at high frequencies due to the domination of resonance behavior
Vertical Interface Induced Dielectric Relaxation in Nanocomposite (BaTiO3)1-x:(Sm2O3)x Thin Films
Vertical interfaces in vertically aligned nanocomposite thin films have been approved to be an effective method to manipulate functionalities. However, several challenges with regard to the understanding on the physical process underlying the manipulation still remain. In this work, because of the ordered interfaces and large interfacial area, heteroepitaxial (BaTiO(3))(1-x):(Sm(2)O(3))(x) thin films have been fabricated and used as a model system to investigate the relationship between vertical interfaces and dielectric properties. Due to a relatively large strain generated at the interfaces, vertical interfaces between BaTiO(3) and Sm(2)O(3) are revealed to become the sinks to attract oxygen vacancies. The movement of oxygen vacancies is confined at the interfaces and hampered by the misfit dislocations, which contributed to a relaxation behavior in (BaTiO(3))(1-x):(Sm(2)O(3))(x) thin films. This work represents an approach to further understand that how interfaces influence on dielectric properties in oxide thin films
Face mask integrated with flexible and wearable manganite oxide respiration sensor
Face masks are key personal protective equipment for reducing exposure to viruses and other environmental hazards such as air pollution. Integrating flexible and wearable sensors into face masks can provide valuable insights into personal and public health. The advantages that a breath-monitoring face mask requires, including multi-functional sensing ability and continuous, long-term dynamic breathing process monitoring, have been underdeveloped to date. Here, we design an effective human breath monitoring face mask based on a flexible La0.7Sr0.3MnO3 (LSMO)/Mica respiration sensor. The sensor’s capabilities and systematic measurements are investigated under two application scenes, namely clinical monitoring mode and daily monitoring mode, to monitor, recognise, and analyse different human breath status, i.e., cough, normal breath, and deep breath. This sensing system exhibits super-stability and multi-modal capabilities in continuous and long-time monitoring of the human breath. We determine that during monitoring human breath, thermal diffusion in LSMO is responsible for the change of resistance in flexible LSMO/Mica sensor. Both simulated and experimental results demonstrate good discernibility of the flexible LSMO/Mica sensor operating at different breath status. Our work opens a route for the design of novel flexible and wearable electronic devices
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Generation, Geography, and Gender Ideology in China
China’s recent gender history is marked by periodic ruptures, with the transition from socialist feminism to market economy accompanied by major paradigm shifts in public discourse on gender roles and status, femininity, and masculinity. This dissertation explores how this shifting gender structure, intertwined with the continuous influence of Confucian family values, economic development, market transition, and educational expansion, manifests in individual-level gender beliefs in contemporary China. Applying a multidimensional conceptualization of gender ideology, it identifies different nationally relevant gender principles and examines their sociodemographic predictors, regional distributions, and covariation across generations of Chinese men and women who came of age during different socioeconomic and political eras. The study explores which aspects of gender-traditionalism endure and why, as well as which forms of gender-egalitarianism take hold during China’s socioeconomic transformations. The mixed-methods research design applied combines latent class analysis and multilevel regression analysis of nationally representative survey data from the Chinese General Social Survey (2010-2017) with analysis of 79 original in-depth interviews conducted with diverse populations in China. This methodology allows for a more comprehensive understanding of China’s gender ideologies and attention to intersectional identities shaped by political generation, geographic origins (e.g., urban vs. rural), and gender.
Key findings reveal a multifaceted and contextually rooted structure to Chinese gender ideology. The coexistence of male-supremacist values and essentialist beliefs about women’s domestic roles, along with an expectation for women’s paid employment—despite their continued subordination—is consistent with the multidimensional nature of gender beliefs observed in other countries. However, the ways in which these gender principles rise and fall, couple and decouple, are distinct in China, influenced by the country’s unique economic, cultural, and political landscapes.
The observed multidimensionality in gender beliefs and their variation across social groups and regions also confirm that market transition is not necessarily accompanied by a uniform liberalization of gender beliefs. Survey results indicate a two-phased evolution of gender beliefs during China’s market transition: initially, traditional gender norms intensified, reflecting a “traditionalizing effect,” but over time, as the market economy matured, there was a shift towards more liberal egalitarian beliefs. Nonetheless, the pervasive market-driven values in contemporary China exacerbate a “double-bind” Chinese women face, torn between paid work and primary caregiving, which naturalizes workplace gender inequalities.
Lastly, the dissertation connects evolving gender beliefs with family dynamics, highlighting potential influences on China’s declining fertility rate and proposing policy recommendations. Altogether, these findings underscore the need to interrogate common narratives about the connection between gender equality and modernization, particularly in societies undergoing rapid socioeconomic transformations. They also illuminate how deeply entrenched gender norms can be recast in changing societal contexts, resulting in novel forms of gender inequality
Three-Dimensional Surface Crack Growth of Maraging Steel Spherical Pressure Shell
This study focused on the three-dimensional surface crack growth of a spherical pressure shell. Eight maraging steel 18Ni (250) samples were fabricated and tested, and the fatigue crack growth rate curves were obtained. Considering the influence of plastic closure effect and sample thickness on crack growth, the fitting formula of fatigue crack growth only related to materials was obtained. Based on the three-dimensional crack closure theory and the strip yield model, a three-dimensional surface crack growth model of spherical pressure shell was established. By using a self-written program and FRANC3D, the three-dimensional surface crack growth simulations of the spherical shell were completed. The influence of the initial shape ratio and initial depth of the crack on the crack growth and the fatigue life of the spherical shell was analyzed
Exploration on Temporal-spatial Difference of Cultivated Land Pressure and Influence Factor Analysis : A Case Study of Guangxi
Based on related statistical data during 1980-2014, change rule of Guangxi cultivated land pressure level was studied. Taking each municipal administrative division as evaluation unit, temporal-spatial change trend of cultivated land pressure level was explored by establishing pressure index model of cultivated land, and principal component analysis was used to explore the driving force of cultivated land pressure. Results showed that from 1980 to 2014 in Guangxi, cultivated land pressure was at level one in 12 years, level two in 19 years and level three in 4 years; mean of cultivated land pressure in each city during 2005-2014 was taken as average level of cultivated land pressure in the city, in which cultivated land pressure values of Chongzuo City, Baise City, Laibin City, Liuzhou City, Fangchenggang City, Nanning City, Hechi City and Guigang City were all lower than average level in Guangxi at the same period. Driving factors of cultivated land pressure index mainly contained urbanization rate, Engel coefficient of rural households (ECRH), per capita cultivated land area, total population and rural per capita net income (RPFI)
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