Fast approximately timed simulation

International audienceIn this paper we present a technique for fast approximately timed simulation of software within a virtual prototyping framework. Our method performs a static analysis of the program control flow graph to construct annotations of the simulated program, combined with dynamic performance information. The static analysis estimates execution time based on a target architecture model. The delays introduced by instruction fetch and data cache misses are evaluated dynamically. At the end of each block, static and dynamic information are combined with branch target prediction to compute the total execution time of the blocks. As a result, we can provide approximate performance estimates with a high simulation speed that is still usable for software developers

How driving duration influences drivers' visual behaviors and fatigue awareness: a naturalistic truck driving test study

AbstractBackground: Commercial truck drivers stay behind the wheel for long hours. Fatigue is thus a major safety concern among such long distance travelling drivers.Objectives: Primarily, the study explored the effects of driving duration on commercial truck drivers’ visual features and fatigue awareness. It also examined the association between visual variables and subjective level of fatigue.Methods: Participants of the study were 36 commercial truck drivers. During the study, the participants were grouped into nine on the basis of the differences in their age and were made to participate in the naturalistic driving test. In the driving test, the participants were asked to finish 2h, 3h, and 4h continuous driving tasks. Ten visual indicators and self awareness of fatigue level of the drivers were recorded during the driving hours. One-way ANOVA and Pearson product-moment correlation were used to analyze each visual indicator’s variation by age groups over time, and its association with subjective level of fatigue.Results: The statistical analysis revealed that continuous driving duration had a significant effect on changes of visual indicators and self-reported fatigue level. After 2h of driving, both the average closure duration value and average subjective fatigue level changed significantly. After 4h of driving, other than the average number of saccades and average pupil diameter, all of the driver’s visual indicators had a significant change. In addition, the change of fatigue level is positively associated with the variation of pupil diameter, fixation duration, blink frequency, blink duration, and closure duration. On the other hand, the change of fatigue level was negatively related to number of fixations, search angle, number of saccade, saccade speed, and saccade amplitude.Conclusion: Driving duration has a significant effect on driver’s visual variation and fatigue level. For commercial truck drivers, traffic laws and regulations should strictly control the amount of their continuous driving time. Moreover, driving fatigue can also be evaluated through the change rate of driver’s visual indicators. Awareness of the rate of change in their driving fatigue level alerts drivers to the risk of fatigue and rest moment. [Ethiop. J. Health Dev. 2018;32(1):36-45

The Development Status of Community Health Management in Japan and Its Enlightenment to China

Community health management is an important element in promoting the Health China initiative and health promotion. As the world's longest-living country, Japan's community health management has become increasingly mature. This paper briefly reviews the development of community health management in Japan under the guidance of the National Health Strategy, compares the assessment framework of its community health management, and summarizes its specific actions in three areas: health check-ups and cancer screening, lifestyle and behavioral interventions and health management of key populations, and proposes inspirations for Japan's community health management for China based on its successful experience

Research Progress on Strontium Function in Foods

Strontium is of great significance to human health and participates in various physiological functions and biochemical effects. It has great prospects in the development of health products and natural medicines. Strontium not only has a protective effect on bone diseases, dental caries and cardiovascular diseases, but also maintains reproductive health. In addition, more and more studies have confirmed that strontium also has many functions such as anti-inflammatory, antioxidant, anti-adipogenesis, anti-cancer, anti-diabetes, pro-angiogenesis and heart protecting functions. In order to provide a theoretical basis for the development of strontium rich foods and the application of strontium in nutrition, this paper reviews the relationship between strontium and calcium, the safety of strontium, and its safety threshold and major physiological functions

Data-Driven Dynamic Inversion Method for Complex Fractures in Unconventional Reservoirs

Hydraulic fracturing is a crucial technology for enhancing the recovery of oil and gas from unconventional reservoirs. Accurately describing fracture morphology is essential for accurately predicting production dynamics. This article proposes a new fracture inversion model based on dynamic data-driven methods, which is different from the conventional linear elastic fracture mechanics model. This method eliminates the need to consider complex mechanical mechanisms, resulting in faster simulation speeds. In the model, the fracture morphology is constrained by combining microseismic data and fracturing construction data, and the fracture tip propagation domain is introduced to characterize the multi-directionality of fracture propagation. The simulated fracture exhibits a multi-branch fracture network morphology, aligning more closely with geological understanding. In addition, the influence of microseismic signal intensity on the direction of fracture propagation is considered in this study. The general stochastic approximation (GSA) algorithm is employed to optimize the direction of fracture propagation. The proposed method is applied to both the single-stage fracturing model and the whole well fracturing model. The research findings indicate that in the single-stage fracturing model, the inverted fracture morphology aligns closely with the microseismic data, with a fitting rate of the fracturing construction curve exceeding 95%, and a microseismic data fitting rate exceeding 93%. In the whole well fracturing model, a total of 18 sections were inverted. The fitting rate between the overall fracture morphology and the microseismic data reached 90%. The simulation only took 5 minutes, demonstrating high computational efficiency and meeting the needs of large-scale engineering fracture simulation. This method can effectively support geological modeling and production dynamic prediction

Integrin β3 Mediates the Endothelial-to-Mesenchymal Transition via the Notch Pathway

Background/Aims: Neointimal hyperplasia is responsible for stenosis, which requires corrective vascular surgery, and is also a major morphological feature of many cardiovascular diseases. This hyperplasia involves the endothelial-to-mesenchymal transition (EndMT). We investigated whether integrin β3 can modulate the EndMT, as well as its underlying mechanism. Methods: Integrin β3 was overexpressed or knocked down in human umbilical vein endothelial cells (HUVECs). The expression of endothelial markers and mesenchymal markers was determined by real-time reverse transcription PCR (RT-PCR), immunofluorescence staining, and western blot analysis. Notch signaling pathway components were detected by real-time RT-PCR and western blot analysis. Cell mobility was evaluated by wound-healing, Transwell, and spreading assays. Fibroblast-specific protein 1 (FSP-1) promoter activity was determined by luciferase assay. Results: Transforming growth factor (TGF)-β1 treatment or integrin β3 overexpression significantly promoted the EndMT by downregulating VE-cadherin and CD31 and upregulating smooth muscle actin α and FSP-1 in HUVECs, and by enhancing cell migration. Knockdown of integrin β3 reversed these effects. Notch signaling was activated after TGF-β1 treatment of HUVECs. Knockdown of integrin β3 suppressed TGF-β1-induced Notch activation and expression of the Notch downstream target FSP-1. Conclusion: Integrin β3 may promote the EndMT in HUVECs through activation of the Notch signaling pathway

An Overview of Recent Development in Composite Catalysts from Porous Materials for Various Reactions and Processes

Catalysts are important to the chemical industry and environmental remediation due to their effective conversion of one chemical into another. Among them, composite catalysts have attracted continuous attention during the past decades. Nowadays, composite catalysts are being used more and more to meet the practical catalytic performance requirements in the chemical industry of high activity, high selectivity and good stability. In this paper, we reviewed our recent work on development of composite catalysts, mainly focusing on the composite catalysts obtained from porous materials such as zeolites, mesoporous materials, carbon nanotubes (CNT), etc. Six types of porous composite catalysts are discussed, including amorphous oxide modified zeolite composite catalysts, zeolite composites prepared by co-crystallization or overgrowth, hierarchical porous catalysts, host-guest porous composites, inorganic and organic mesoporous composite catalysts, and polymer/CNT composite catalysts

Distributed time, conservative parallel logic simulation on GPUs

Logical simulation is the primary method to verify the correctness of IC designs. However, today’s complex VLSI designs pose ever higher demand for the throughput of logic simulators. In this work, a parallel logic simulator was developed by leveraging the com-puting power of modern graphics processing units (GPUs). To expose more parallelism, we implemented a conservative parallel simulation approach, the CMB algorithm, on NVidia GPUs. The simulation processing is mapped to GPU hardware at the finest granularity. With carefully designed data structures and data flow organizations, our GPU based simulator could overcome many problems that hindered efficient implementations of the CMB algorithm on traditional parallel computers. In order to efficiently use the relatively limited capacity of GPU memory, a novel mem-ory management mechanism was proposed to dynamically allo-cate and recycle GPU memory during simulation. We also intro-duced a CPU/GPU co-processing strategy for the best usage of computing resources. Experimental results showed that our GPU based simulator could outperform a CPU baseline event driven simulator by a factor of 29.2