Search

To study the vehicle–bridge interaction (VBI) of highway bridges under seismic excitation, a vehicle–bridge couple analysis method based on Ansys is proposed. The 1/2 vehicle model and space beam element model were established to analyze the VBI response of Lanzhou Xiaoshagou bridge. The self-excited excitation of the system is represented by road surface irregularity randomness, while the external excitation is represented by an earthquake. The impact of seismic types, seismic direction, seismic intensity, vehicle speed, and road surface irregularity on the bridge vibration under the vehicle–bridge coupling during an earthquake is thoroughly analyzed. The results reveal that the type of earthquake significantly influences the dynamic response of the bridge, showing a minimum difference of 31.4%. The intensity of the earthquake is positively correlated with the dynamic response of the bridge. Longitudinal and vertical earthquakes have a more noticeable effect on the bridge's vertical vibration compared to lateral earthquakes. The ratio of the bridge response under vertical or longitudinal seismic excitation to the response of lateral earthquakes ranges from 1.50 to 26.61. Vehicle speed, road irregularity grade, and randomness have a negligible impact on the dynamic response of vehicle–bridge interaction under an earthquake, accounting for less than 3%. These findings indicate that the analysis of earthquake-bridge vibration can simplify the VBI analysis for continuous rigid frame composite box girder bridges with corrugated steel webs under seismic conditions. [ABSTRACT FROM AUTHOR]

Spinal cord injury (SCI) is a highly disabling disorder for which few effective treatments are available. Grape seed proanthocyanidins (GSPs) are polyphenolic compounds with various biological activities. In our preliminary experiment, GSP promoted functional recovery in rats with SCI, but the mechanism remains unclear. Therefore, we explored the protective effects of GSP on SCI and its possible underlying mechanisms. We found that GSP promoted locomotor recovery, reduced neuronal apoptosis, increased neuronal preservation, and regulated microglial polarisation in vivo. We also performed in vitro studies to verify the effects of GSP on neuronal protection and microglial polarisation and their potential mechanisms. We found that GSP regulated microglial polarisation and inhibited apoptosis in PC12 cells induced by M1-BV2 cells through the Toll-like receptor 4- (TLR4-) mediated nuclear factor kappa B (NF-κB) and phosphatidylinositol 3-kinase/serine threonine kinase (PI3K/AKT) signaling pathways. This suggests that GSP regulates microglial polarisation and prevents neuronal apoptosis, possibly by the TLR4-mediated NF-κB and PI3K/AKT signaling pathways.

This study developed a mobile app called Ubiquitous-Physics (U-Physics), which helps students explore inclined plane phenomena in authentic contexts and consolidates their physics learning in everyday contexts. The study investigated inquiry behaviors such as interpreting graphs, applying formulas, drawing conclusions, and peer sharing, and how these influenced learning achievements. The app’s effects on learning perceptions and motivation were also analyzed. The study was conducted at a vocational senior high school and two activities (indoors and outdoors/authentic contexts). The results show that the experimental group using U-Physics significantly outperformed the control group, who used traditional tools such as a stopwatch for the inclined plane experiment in terms of learning achievements. Analysis of the correlations among inquiry behaviors and learning achievement revealed that the number of posts in authentic contexts had the greatest influence on learning achievement, confirming the importance of applying physics concepts in authentic contexts. Additionally, most students reported positive perceptions of the U-Physics app and were highly motivated to use it for future learning. The findings indicate that using U-Physics in authentic contexts is very meaningful and can contribute to physics learning, particularly when using mobile devices with sensors to facilitate inquiry learning in authentic physics scenarios.

In this study, an application (app) called ezTranslate was developed to aid English as foreign language (EFL) learning by assigning lessons that adapt to students' interests, in order to motivate them to engage concurrently in physical activity in a real context. ezTranslate was developed by combining state-of-the-art technologies--automatic speech recognition and a cloud translation service, which permit effortless language translation. ezTranslate also offers user-oriented, self-speaking practice opportunities via its speech shadowing function. This app is designed (1) as an effective support tool for EFL speaking in authentic contexts and (2) to engage students in exercise as they walk in their environment. Results suggest that using ezTranslate in familiar situations significantly promotes student cooperation, as evidenced by their increased listening and speaking. Furthermore, there were significant differences in English speaking performance and homework aptitude in participants when using ezTranslate with or without authentic contexts. Indeed, this study's findings emphasize the importance of authentic support for EFL speaking; namely, students' interests. The familiarity and fascination of students with real contexts can motivate them to communicate in English better and more frequently. As for the effect of exercise on EFL learning, statistical analysis revealed that the more steps students take, the more they practice speaking English. These results are very promising. Creating an interactive medium in which students not only acquire knowledge but also move their bodies promotes brain and body activity vital to their overall health. In the near future, we plan to extend activity design, executing authentic drama-play to sustain effective, healthy EFL learning.

A new approach is presented in this paper for the dynamic modeling of the chemical and isotopic evolution of C1–3 during the hydrocarbon generation process. Based on systematic data obtained from published papers for the pyrolysis of various hydrocarbon sources (type I kerogen/source rock, type II kerogen/source rock, type III kerogen/source rock, crude oil, and asphalt, etc.), the empirical evolution framework of the chemical and isotopic composition of C1–3 during the hydrocarbon generation process was built. Although the empirical framework was built only by fitting a large amount of pyrolysis data, the chemical and isotopic composition of C1–3 derived from the pyrolysis experiments all follow evolution laws, convincing us that it is applicable to the thermal evolution process of various hydrocarbon sources. Based on the simplified formula of the isotopic composition of mixed natural gas at different maturities (δ13Cmixed), δ13Cmixed = X × n i A × δ 13 C i A + Y × n i B × δ 13 C i B X × n i A + Y × n i B , it can be derived that the cumulative isotopic composition of alkane generated in a certain maturity interval can be expressed by the integral of the product of the instantaneous isotopic composition and instantaneous yield at a certain maturity point, and then divided by the cumulative yield of alkane generated in the corresponding maturity interval. Thus, the cumulative isotopic composition (A(X)), cumulative yield (B(X)), instantaneous isotope (C(X)), and instantaneous yield (D(x)) in the dynamic model, comply with the following formula during the maturity interval of (X0~X). A(X) = ∫ X 0 X C X × D X d x B (X) , where A(X) and B(X) can be obtained by the fitting of pyrolysis data, and D(x) can also be obtained from the derivation of B(X). The dynamic model was applied on the pyrolysis data of Pingliang Shale to illustrate the quantitative evolution of the cumulative yield, instantaneous yield, cumulative isotope, and instantaneous isotope of C1–3 with increasing maturity. The dynamic model can quantify the yield of methane, ethane, and propane, as well as δ13C1, δ13C2, and δ13C3, respectively, during the hydrocarbon generation process. This model is of great significance for evaluating the natural gas resources of hydrocarbon source rock of different maturities and for identifying the origin and evolutionary process of hydrocarbons by chemical and isotopic data. Moreover, this model provides an approach to study the dynamic evolution of the isotope series of C1–3 (including reversed isotopic series), which is promising for revealing the mechanism responsible for isotopic reversal when combined with post-generation studies. [ABSTRACT FROM AUTHOR]

This paper presented the design of a novel general signal processing system based on the partial reconfiguration of Field Programmable Gate Array(FPGA). This solution uses framework of high speed FPGA，Digital Signal Processor(DSP) and Analog/Digital Convertor(DAC), and supports the performing, storing and dynamically reconfiguring of dozens of waveforms in three channels. This system is suitable for the miniaturization application.

Carbon plays an important role in global climate change. The mechanisms of carbon sources and carbon sinks have also received wide attention from society, and the physical and chemical characteristics of riverine ions can reflect the chemical weathering of rocks and carbon sink capacity of river basins. Based on the data on river, rainwater, and rock samples from 2019, this study used various methods, such as ion ratio diagrams and ternary diagrams, to analyze the chemical characteristics of water; the chemical weathering and carbon sink effects of rocks were also calculated while assuming three scenarios based on the main sources of ions in the Naqu River. The results showed that for the whole catchment, the main ion sources in the river were: carbonate rock chemical weathering > silicate rock chemical weathering > evaporite dissolution > atmospheric precipitation input. According to the calculations, in the three scenarios, the carbonate weathering rates were 16.84, 11.32, and 14.08 t/km2/yr, and the carbon sink capacities were 66.47, 121.13, and 93.80 mol/km2/yr, respectively; the evaporite weathering rates were 2.20, 9.63, and 5.92 t/km2/yr, respectively. The silicate chemical weathering rate and carbon sink capacity did not change significantly in either scenario, with 6.82 t/km2/yr and 248.6 mol/km2/yr, respectively. This study quantified the ion sources in the Naqu River basin and accurately analyzed their chemical genesis, which helps in understanding the role of the rivers of the Qinghai–Tibet Plateau in the global carbon cycle and global climate change, in addition to providing a reference for the scientific development of the Nujing River. [ABSTRACT FROM AUTHOR]

The Yellow River Basin holds significance as a vital ecological shield and economic hub within China. Adapting land utilization practices and optimizing landscape patterns are of paramount significance in preserving the ecological equilibrium of the Yellow River Basin while fostering high-quality economic development. In this study, we selected the Yellow River Basin in Henan Province as our research area. We use a land use transition matrix and FRAGSTATS 4.2 software to analyze changes in land use and landscape patterns within the study area from 1990 to 2020. Furthermore, Geographical Detector is employed to explore the impact of different natural and social economic factors that have influenced the progress of the landscape surface pattern in the study area. Finally, to identify the zonal aggregation effects of primary components in connection with landscaping feature indices at the city dimension, we use bivariate local spatial autocorrelation. The results are as follows: (1) In terms of land use change characteristics, the area of cultivated land, grassland, shrubs, and bare land shows a decreasing tendency, the area of construction land and forest land shows an increasing tendency, and the water area fluctuates and changes. Most of the cultivated land is shifted to construction land, followed by forest land, construction land, and cultivated land mainly transferred from grassland. (2) At the level of type in terms of shifting landscape patterns, cultivated land, forest land, water, and construction land have a more complex landscape shape, reduced fragmentation, and better natural connectivity. At the overall level, the overall landscape pattern indices are relatively stable, with more patch types and a more balanced distribution. (3) The findings regarding influencing factors reveal that the primary industry output value, population, secondary industry output value, and temperature are the principal driving forces behind the progress of the landscape surface pattern. The main drivers have changed over time in different regions. As indicated by the findings from bivariate local spatial autocorrelation analysis, at the city scale, the leading cause of landscape fragmentation in Luoyang is the primary industry output value, while in Xinxiang, landscape fragmentation is primarily driven by the secondary industry output value and temperature. In this study, we introduce the bivariate local spatial autocorrelation method to analyze the clustering effects of key influencing factors and landscape patterns at the city scale. This is crucial for the harmonized growth of land use planning and the urban economy in the Yellow River Basin. [ABSTRACT FROM AUTHOR]

[Objectives] In response to the need for improved habitability arising from the harsh environment of submarine accommodation, this paper studies the conditioned air distribution for submarine accommodation equipped with spherical air distributors,and evaluate the thermal comfort of the accommodation.[Methods] A high-precision three-dimensional model of accommodation is constructed with CATIA,and according to the actual boundary conditions,the numerical simulation of air distribution in the accommodation under surface and underwater conditions in summer and winter,and the numerical simulation of the conditioned air distribution in the accommodation with spherical air distributors under summer surface condition are carried out by using the Computational Fluid Dynamics(CFD)technology. Besides,the distribution of the air temperature and velocity in the accommodation under each working condition is analyzed and compared,and the PMV value of the accommodation is calculated and analyzed.[Results] It is shown that the PMV values of the accommodation are -1-1 under each working condition, the air velocity distribution in most areas of the accommodation is uniform,with the average air velocity of less than 0.3 m/s,and the temperature distribution in most areas of the accommodation is uniform,with average air temperature of about 24.5-26℃ in summer,and about 22-23.5℃ in winter.[Conclusions] The typical air conditioning comfort of the submarine accommodation equipped with spherical air distributors is up to the standard.

In this study, an application (app) called ezTranslate was developed to aid English as foreign language (EFL) learning by assigning lessons that adapt to students’ interests, in order to motivate them to engage concurrently in physical activity in a real context. ezTranslate was developed by combining state-of-the-art technologies—automatic speech recognition and a cloud translation service, which permit effortless language translation. ezTranslate also offers user-oriented, self-speaking practice opportunities via its speech shadowing function. This app is designed (1) as an effective support tool for EFL speaking in authentic contexts and (2) to engage students in exercise as they walk in their environment. Results suggest that using ezTranslate in familiar situations significantly promotes student cooperation, as evidenced by their increased listening and speaking. Furthermore, there were significant differences in English speaking performance and homework aptitude in participants when using ezTranslate with or without authentic contexts. Indeed, this study’s findings emphasize the importance of authentic support for EFL speaking; namely, students’ interests. The familiarity and fascination of students with real contexts can motivate them to communicate in English better and more frequently. As for the effect of exercise on EFL learning, statistical analysis revealed that the more steps students take, the more they practice speaking English. These results are very promising. Creating an interactive medium in which students not only acquire knowledge but also move their bodies promotes brain and body activity vital to their overall health. In the near future, we plan to extend activity design, executing authentic drama-play to sustain effective, healthy EFL learning.