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The water stop between the pier cap and the steel pipe pile is a key process for the installation of prefabricated piers and abutments. It is difficult to install the water stop for prefabricated piers and abutments because the construction of post cast holes needs to be carried out in a dry working environment. In order to improve the construction efficiency of pier and abutment installation and improve the water stop quality, the tray lifting water stop scheme and steel hoop water stop scheme are designed according to the project requirements, and the steel hoop water stop scheme is optimized from the operational and economic aspects to carry out the prefabricated pier and abutment water stop construction. The hoop is connected to the hanging beam at the top of the steel pipe pile through the fine rolled threaded reinforcement. A single peak water stop is set between the top surface of the hoop and the bottom of the pile cap. The lifting beam compresses the water stop to achieve horizontal water stop, and the compression rubber plate is tightly held between the hoop and the steel pipe pile to achieve vertical water stop. Through the same scale simulation experiments and optimization improvement based on the test results, the steel hoop water stop process can meet the construction water stop demand, and realize the dry operation environment under the water head difference of 8 meters. It has the advantages of high efficiency, good water stop effect, and recyclable use. [ABSTRACT FROM AUTHOR]

Water level is crucial to the growth and development of wetland plants, in order to study the physiological and ecological responses of Pomatogeton crispus under different water levels, in the study, P. crispus were placed under 50 cm (control) and 60–135 cm water levels following a 15 cm gap gradient for 60 days in a simulation experiment. The results showed that: (1) As the water level gradient increased, the plant height, leaf number and biomass of P. crispus showed a trend of increasing and then decreasing. (2) The concentrations of chlorophyll a (Chl-a), chlorophyll b (Chl-b), chlorophyll a + b (Chl a + b) and carotenoids (Car) showed a multi-peak increasing trend with increasing water level, with the maximum values occurring in the 135 cm water level group. (3) The antioxidant enzymes of P. crispus showed a fluctuating upward trend with increasing water level, and the higher the water level the greater the difference within the group, and rooting activity of P. crispus was significantly increased under elevated water level conditions. (4) The P. crispus grows best in the water level range of 105 ∼ 120 cm, and the growth indexes such as the number of leaves and biomass all reach higher values in the water level of 105 ∼ 120 cm, If the water level is too high or too low, it has an effect on the growth and development of P. crispus. [ABSTRACT FROM AUTHOR]

In order to research the laws of roof collapsing and overlaying stratum movement in close distance coal seams mining and prevent roof accidents during such mining. The close distance coal seams mining in a coal mine is used as the study subject in this study, and a similar simulation experiment is conducted. A similar simulation experiment of the close distance coal seams is seen using the digital image correlation. The evolution of roof displacement–strain in the mining process is researched, along with the roof caving features in various coal seam mining processes. The evolution law of roof stress-displacement is revealed in the mining process of close distance coal seams which provides the basis for the roof stability control in close distance coal seams. Lower coal seam mining in close distance coal seams has a larger degree of abutment pressure stress concentration and a higher level of advanced abutment pressure intensity. Greater harm is caused by lower coal seam roof strata mining than by single coal seam mining. The stope support strength design must take upper goaf influence into account. Therefore, to ensure the stope roof stability in close distance coal seams, it is necessary to implement roof pressure monitoring, stope roof's grouting reinforcement, measures to improve the performance of hydraulic support, and roof effective control in close distance coal seams mining by using the principle of coordinated control. [ABSTRACT FROM AUTHOR]

The fatigue allowance effectively mitigates declines in physiological state due to work fatigue. An appropriate allowance rate facilitates timely recovery for employees and serves as a crucial basis for labor quota formulation. In this paper, the action mode in mechanical processing was extracted and disassembled into six action units. The study conducted fatigue measurement experiments based on physiological measurement methods, including exercise fatigue tests at different frequencies and work fatigue tests over varying durations. As the frequency of actions increased, the rate monotonic scheduling index showed a linear increasing trend and the degree of fatigue caused by the action was different. The fatigue coefficient of different action units and the fatigue index of the fatigue instability period were obtained by fitting. Hazard ratio indicators showed significant differences, and the corresponding fatigue recovery rest time was obtained for different continuous operation hours. By further fitting the above data, a fatigue relaxation rate model suitable for simulating operation methods was obtained (the fatigue coefficient for the simulated operations in this study is 0.076152) which could provide a reasonable basis for the formulation of fatigue allowance rates for machining methods. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Jilin University (Science Edition) / Jilin Daxue Xuebao (Lixue Ban) is the property of Zhongguo Xue shu qi Kan (Guang Pan Ban) Dian zi Za zhi She and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to improve the maintenance and management efficiency of campus electromechanical equipment and reduce or even avoid the safety risks brought by campus electromechanical equipment, this work uses the data mining algorithm to design the security and protection system of campus electromechanical equipment. First, this work constructs the campus electromechanical equipment classification model using the Bayesian algorithm of data mining algorithm and designs a simulation experiment to verify the effect of the classification model. Then, the security and protection system for the campus electromechanical equipment is designed. It includes the system business process, system function design, system core module's function design and system implementation. Finally, a simulation experiment is designed to verify the system's performance. The results show that: (1) Bayesian algorithm is superior to the K-Nearest Neighbor (KNN) algorithm in both classification effect and running time. (2) When the browser concurrency in the system increases, the server processor and memory usage also increases, but the value meets the expected requirements. It shows that the system has a certain browser concurrency-bearing capacity. Moreover, as the browser concurrency of the system increases, the response time of the test also increases, but the value meets the expected requirements. This work aims to improve the maintenance efficiency of campus electromechanical equipment and provide a reference for the safety protection work of electromechanical equipment in other enterprises or units. [ABSTRACT FROM AUTHOR]

Granulation is an ancient and sophisticated decorative technique. The production of granules is a crucial part of this process but has rarely been studied. The present study employed three techniques—pouring method, heating method, and crucible method—to produce gold granules. The success ratio of granule formation, granule surface morphology, microstructure, and formation were analyzed to identify the techniques used in archaeological objects. The cooling medium significantly influenced small granule formation, microstructure, and grain size. Both heating and crucible methods could control the granule formation, but these methods produced distinct microstructures. Based on these experimental granules, the probable production methods of ancient gold balls were identified. The present study provided microscopic information for determining ancient gold granule production techniques. [ABSTRACT FROM AUTHOR]

In the context of global climate change, the frequency of waterlogging is increasing. Therefore, to elucidate the effects of waterlogging under real precipitation conditions on the physiological characteristics of peanuts and the underlying mechanics and to provide a theoretical basis for timely protective measures, this study involved a waterlogging disaster simulation experiment in the field environment and a waterlogging stress control experiment in the potting environment. It was found that sufficient water had a positive effect on the growth and development of peanuts (Arachis hypogaea L.) during the 3–5 days period at the beginning of waterlogging. However, as the duration of waterlogging increased, excess water inhibited the growth of peanuts, with a stronger inhibitory effect on the development of pods. A comparison of the two different experimental models found that in the potting environment, water circulation was not smooth, and the intensity of waterlogging was higher than in the field environment experiment, resulting in the effect of waterlogging being advanced by one observation stage (2 days) in the potting environment. Furthermore, using a novel fluorescence imaging system, an analysis of variations in the physiological characteristics of leaf sections demonstrated that the chlorophyll fluorescence in the leaves of the peanut plant exhibited a specific pattern in response to waterlogging stress. [ABSTRACT FROM AUTHOR]

This study investigates the coevolution of coauthorship and citation networks and their influence on scientific metrics such as the h-index and journal impact factors. Using a preferential attachment mechanism, we developed a model that integrated these networks and validated it with data from the American Physical Society (APS). While the correlations between reference counts, paper lifetime, and team sizes with scientific impact metrics are well-known, our findings demonstrate how these relationships vary depending on specific model parameters. For instance, increasing reference counts or reducing paper lifetime significantly boosts both journal impact factors and h-indexes, while expanding team sizes without adding new authors can artificially inflate h-indexes. These results highlight potential vulnerabilities in commonly used metrics and emphasize the value of modeling and simulation for improving bibliometric evaluations. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Geology & Oilfield Development in Daqing is the property of Editorial Department of Petroleum Geology & Oilfield Development in Daqing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Granulation is an ancient and sophisticated decorative technique. The production of granules is a crucial part of this process but has rarely been studied. The present study employed three techniques—pouring method, heating method, and crucible method—to produce gold granules. The success ratio of granule formation, granule surface morphology, microstructure, and formation were analyzed to identify the techniques used in archaeological objects. The cooling medium significantly influenced small granule formation, microstructure, and grain size. Both heating and crucible methods could control the granule formation, but these methods produced distinct microstructures. Based on these experimental granules, the probable production methods of ancient gold balls were identified. The present study provided microscopic information for determining ancient gold granule production techniques.

Over recent years, as digitalization and intelligence in oil wellbore have increased, so have the stricter requirements for wireless communication technology in terms of distance, accuracy, and portability. As a result, it's necessary to rely on more advanced and efficient wireless communication technologies to meet the industry's needs. However, traditional communication technologies such as cables and optical fibers have inherent shortcomings in construction, data interpretation, and cost. ELF electromagnetic waves are an ideal solution for communication in complex wellbore conditions due to long-distance communication and strong penetration capabilities, making it a highly effective option. Based on the theory of network splitting, this paper establishes a polygonal multiple-delays uncertainty coupled complex network model of ELF electromagnetic waves propagating through the casing in layered media and designs a controller, including expressions for the intensity of the magnetic and electric fields in different directions, and the propagation and distribution characteristics in different media. We determined that the optimal transmitting frequency of ELF electromagnetic waves under general conditions is 12.7 Hz. Based on field experiments, we verified that ELF electromagnetic waves can enable wireless wellbore communication within 1500 m without relays. We also analyzed the impact of casing thread deformation on ELF electromagnetic wave propagation due to high-temperature and high-pressure environments. We used simulation experiments to solve the distribution relationship between the electric and magnetic fields of the solenoids through casing and strata, as well as the coupling coefficients between the transmitting and receiving solenoids, and explore how different transmitting frequencies affect the efficiency of signal propagation. Both theories and experiments have verified the correctness of the model, and have also demonstrated the reliability and continuity of using ELF electromagnetic waves to achieve wireless wellbore communication, which provides a theoretical basis and feasibility for subsequent engineering applications. [ABSTRACT FROM AUTHOR]

Knowledge graph based search is becoming increasingly close to users' reading habits, providing a more user-friendly interactive experience. Integrating knowledge graphs as auxiliary information into recommendation algorithms can model and integrate semantic information of learning resources, providing more diverse personalized recommendation results and better alleviating the problem of information overload. In order to solve the problem of readers searching for suitable digital book resources and improve reading efficiency, the first step is to study the construction of knowledge graphs, including core tasks such as knowledge extraction, knowledge representation, and knowledge storage; Then, a mathematical model is constructed, based on the optimized graph convolutional network layer and the quantification algorithm of knowledge point centrality, to construct a universal computational framework for attention mechanism; Finally, simulation experiments were conducted to compare and analyze different models through evaluation indicators, in order to verify the advantages of the model constructed in this paper. The experimental results show that the research method proposed in this paper is superior to conventional methods such as FM, CKE, DNN, NFM, CFKG, KGAT, and KGCN. [ABSTRACT FROM AUTHOR]

Grain size analysis is used to study grain size and distribution. It is a critical indicator in sedimentary simulation experiments (SSEs), which aids in understanding hydrodynamic conditions and identifying the features of sedimentary environments. Existing methods for grain size analysis based on images primarily focus on scenarios where grain edges are distinct or grain arrangements are regular. However, these methods are not suitable for images from SSEs. We proposed a deep learning model incorporating histogram layers for the analysis of SSE images with fuzzy grain edges and irregular arrangements. Firstly, ResNet18 was used to extract features from SSE images. These features were then input into the histogram layer to obtain local histogram features, which were concatenated to form comprehensive histogram features for the entire image. Finally, the histogram features were connected to a fully connected layer to estimate the grain size corresponding to the cumulative volume percentage. In addition, an applied workflow was developed. The results demonstrate that the proposed method achieved higher accuracy than the eight other models and was highly consistent with manual results in practice. The proposed method enhances the efficiency and accuracy of grain size analysis for images with irregular grain distribution and improves the quantification and automation of grain size analysis in SSEs. It can also be applied for grain size analysis in fields such as soil and geotechnical engineering. [ABSTRACT FROM AUTHOR]

Traditional Jiangnan garden architecture in China offers distinct spatial impressions that hold significance in contemporary architectural expression. Yet, the understanding and analysis of these spaces have historically relied on subjective, sensory experiences, often lacking precise, quantitative research. Consequently, establishing clear logical connections between visual cognition and emotional perception within these spatial experiences has been a challenge. This study introduces virtual reality spatial simulation and quantification techniques, summarizing key Jiangnan garden spatial characteristics and prototypes. It includes a series of virtual reality experiments focusing on cognitive experiences within Jiangnan garden spaces. A comprehensive analysis of isovisit quantitative data, questionnaires, and behavioral information explores the logical relationships between emotional perceptions (calmness, surprise, interest, confusion) and visual cognition qualities (openness, complexity, theatricality) in garden space impressions. This research aims to reveal deeper connections between garden space qualities, visual cognition, and emotional experiences, offering valuable insights for the application of historical traditional spatial features in contemporary architecture. It bridges the gap between sensory experiences and rational analysis, enhancing our understanding of the intricate spatial narratives within Jiangnan gardens. [ABSTRACT FROM AUTHOR]

The purpose of this paper is the design of a potato drip irrigation tape recycling machine that would not require manual assistance or suffer from broken tapes. To clarify the recycling performance of the new potato drip irrigation tape recycling machine under different working parameters, a single-factor performance experiment was conducted. To investigate the reasons for variations in the performance indexes of the machine under different operating parameters, RecurDyn-EDEM coupled simulation experiments were carried out, with the peak height of soil and the maximum bending angle of the drip irrigation tape during the recycling process as the experimental indexes. To determine the optimal working parameter combinations and to clarify the effects of the interaction of various factors on the performance indexes, a response surface experiment was conducted. Following this, an analysis of variance was performed, and a mathematical regression model was established based on the experimental results. The findings revealed that a machine forward speed of 2.4 km/h, a shovel angle of 12°, and a conveyor sprocket speed of 270 r/min resulted in a drip irrigation tape recovery rate of 95.2%, meeting the relevant standards for drip irrigation tape recycling operations. [ABSTRACT FROM AUTHOR]

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article presents simulation modeling as a mathematical basis for the study of logistic systems. The object is pharmaceutical logistics - logistics chains of pharmaceutical companies. Attention is focused on the problems of functioning of domestic pharmaceutical logistics in the conditions of military realities. The expediency of using simulation modeling technologies to reproduce the changing, force majeure conditions of functioning of the supply channels of finished pharmaceutical products is substantiated. Models of one-level and two-level sales channels for pharmaceutical products, built using the discrete-event simulation paradigm on the software platform of the AnyLogic system, are presented. The results of the simulation are illustrated by fragments of simulation experiments based on the materials of the pharmaceutical company FARMAK. [ABSTRACT FROM AUTHOR]

To address the challenges of indoor mold in southern China, this study designed and constructed an innovative experimental system to investigate mold growth in buildings under the combined influence of multiple factors. Using Fluent simulation (Ansys Fluent 19.0), we designed a suitably sized experimental chamber to realistically replicate the effects of factors such as temperature, humidity, and air velocity on mold growth. After establishing and fine-tuning the experimental system, we conducted two preliminary experiments, successfully validating the feasibility of our setup. Additionally, we observed that in a high-temperature, high-humidity environment of 28 °C and 80% relative humidity, the mold growth rate in the experimental chamber increased with the rise in inlet air velocity. This experimental system will serve as the foundation for future studies on indoor mold growth in building spaces in southern China. [ABSTRACT FROM AUTHOR]

Purpose: In order to reduce the waste of mineral resources and improve the utilization rate of lean ore, considering the influence of insufficient ore surplus and the limited amount of shovel loading equipment on the selection of loading points in large metal open-pit mines, a loading point selection model was established with the objectives of minimum grade deviation, minimum production cost and shortest total queuing time of vehicles. Method: A two-dimensional matrix integer coding method is adopted, and an indirect quadratic genetic optimization algorithm based on random fragment crossing and specific mutation operators is designed to solve the model. Result: Taking the actual production data of a large metal open-pit mine in China as an example, the simulation results show that the loading point selection scheme can still meet the requirements of the ore allocation plan under the condition that the number of shovel loading equipment is limited and the remaining ore of priority mining is relatively small. Conclusion: The proposed model and algorithm can be generally applied to large-scale metal open-pit mining, and the ore at the loading point can be fully utilized. Significance: It improves the economic benefit of the enterprise and the overall mining efficiency of the mine. [ABSTRACT FROM AUTHOR]

Species distribution modeling (SDM) is a fundamental tool in theoretical and applied ecology. However, relatively little is known about the performance of different approaches for scale optimization, model selection, and algorithmic prediction in the context of nonlinear, multiscale and interactive relationships between environmental variables and species occurrence. Modelers often struggle to optimize a tradeoff between ecological relevance, model robustness, complexity, and overfitting. In this paper, we investigated several methods designed to optimize spatial scale and variable selection in SDMs, in each case evaluating model fitness, parsimony and predictive performance. We used a simulation approach to produce a large pool of alternative underlying habitat relationships that reflect a broad range of realistic habitat associations. We also compared several different modeling algorithms, including logistic regression with a generalized linear model (GLM), Lasso and Elastic-Net Regularized GLMs (GLMNet), and random forest (RF), as well as alternative variable and scale selection methods. We found that GLM methods employing all-subsets dredge routines for variable selection were consistently the best predictors based on all criteria of our model performance assessment and across all attributes of the simulated underlying relationship, including nonlinearity and interaction. We had expected machine learning approaches, such as random forest, to perform better in these more complex forms of species-environment relationships. GLM using dredge variable selection was also the method that included the fewest spurious covariates and included the most correct predictors as a proportion of all predictors. We found that univariate scaling was the most robust method of variable and scale selection, along with Minimal Redundancy Maximal Relevancy (MRMR) which performed equivalently. The simulation experiment presented here provides a robust assessment of simulated multi-species distribution model performance, complexity and fidelity. By simulating a large range of potential habitat relationships with varying spatial scale, effect sizes, linearity, and interactions, we comprehensively evaluated model performance across gradients of complexity of the underlying relationships and violations of classical statistical assumptions. This study provides a valuable assessment and a broader example of the power and utility of controlled simulation experiments in habitat relationships and other ecological spatial predictive modeling.

Abstract With the acceleration of urbanization in China, the urban population continues to grow, leading to frequent occurrences of crowded public spaces, which in turn trigger traffic congestion and even safety accidents. In order to more effectively control pedestrian flow, enhance the efficiency and safety of public spaces, this experiment conducts in-depth research and improvement on the traditional Dynamic Window Approach (DWA), and applies it to the fine control of pedestrian flow. Specifically, this study comprehensively reviews and analyzes the characteristics of pedestrian traffic flow and the working principles of traditional DWA. Based on this, the shortcomings of traditional DWA in dealing with complex pedestrian flow scenarios are identified, and targeted improvement solutions are proposed. The core of this improvement scheme lies in the introduction of a new evaluation function, enabling DWA to more accurately balance various factors in the decision-making process, including pedestrian movement speed, direction, and spatial distribution. Subsequently, the improved DWA is validated through simulation experiments. The experimental scenario is set in an area of 18 m*18 m, and compared with traditional DWA, the improved DWA shows significant advantages in trajectory length and travel time. Specifically, the trajectory length of the traditional DWA robot is 19.4 m, with a required time of 34.8 s, while the trajectory length of the improved DWA robot is shortened to 18.7 m, and the time is reduced to 18.6 s. This result fully demonstrates the effectiveness of the improved DWA in optimizing pedestrian flow control. The improved DWA proposed in this study not only has strong scientific validity but also demonstrates high efficiency in practical applications. This study has important reference value for improving the safety of urban public spaces and improving pedestrian traffic flow conditions, and provides new ideas for the further development of pedestrian flow control technology in the future.

The supply chain regards suppliers, producers, and consumers as an organic whole, unifying and coordinating the information flow, logistics, and capital flow of all members, and achieving the goal of win-win for all members in the overall operation of cross organization. Demand forecasting is an important factor driving the entire supply chain, and low error rates in forecasting are a common goal pursued by the industry. In order to improve the quality of demand forecasting, enhance the efficiency of supply chain operations, and leverage the important role of machine learning in the era of artificial intelligence, this paper conducts research based on LSTM. Firstly, this paper determines the objective function and constraints for supply chain demand forecasting; Then, this paper constructs a supply chain demand prediction model, based on the LSTM network structure, determine the network training method and model construction process; Finally, this paper conducts simulation experiments and result analysis, configure LSTM parameters, determine model performance evaluation indicators, and compare and analyze actual values with predicted values. The results indicate that the supply chain demand prediction model constructed in this article has very good performance and has promotional value in practice. [ABSTRACT FROM AUTHOR]

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Ecology & Rural Environment is the property of Journal of Ecology & Rural Environment Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the acceleration of urbanization in China, the urban population continues to grow, leading to frequent occurrences of crowded public spaces, which in turn trigger traffic congestion and even safety accidents. In order to more effectively control pedestrian flow, enhance the efficiency and safety of public spaces, this experiment conducts in-depth research and improvement on the traditional Dynamic Window Approach (DWA), and applies it to the fine control of pedestrian flow. Specifically, this study comprehensively reviews and analyzes the characteristics of pedestrian traffic flow and the working principles of traditional DWA. Based on this, the shortcomings of traditional DWA in dealing with complex pedestrian flow scenarios are identified, and targeted improvement solutions are proposed. The core of this improvement scheme lies in the introduction of a new evaluation function, enabling DWA to more accurately balance various factors in the decision-making process, including pedestrian movement speed, direction, and spatial distribution. Subsequently, the improved DWA is validated through simulation experiments. The experimental scenario is set in an area of 18 m*18 m, and compared with traditional DWA, the improved DWA shows significant advantages in trajectory length and travel time. Specifically, the trajectory length of the traditional DWA robot is 19.4 m, with a required time of 34.8 s, while the trajectory length of the improved DWA robot is shortened to 18.7 m, and the time is reduced to 18.6 s. This result fully demonstrates the effectiveness of the improved DWA in optimizing pedestrian flow control. The improved DWA proposed in this study not only has strong scientific validity but also demonstrates high efficiency in practical applications. This study has important reference value for improving the safety of urban public spaces and improving pedestrian traffic flow conditions, and provides new ideas for the further development of pedestrian flow control technology in the future. [ABSTRACT FROM AUTHOR]

NASA's Perseverance and ESA's Rosalind Franklin rovers have the scientific goal of searching for evidence of ancient life on Mars. Geochemical biosignatures that form because of microbe-mineral interactions could play a key role in achieving this, as they can be preserved for millions of years on Earth, and the same could be true for Mars. Previous laboratory experiments have explored the formation of biosignatures under closed systems, but these do not represent the open systems that are found in natural martian environments, such as channels and lakes. In this study, we have conducted environmental simulation experiments using a global regolith simulant (OUCM-1), a thermochemically modelled groundwater, and an anaerobic microbial community to explore the formation of geochemical biosignatures within plausible open and closed systems on Mars. This initial investigation showed differences in the diversity of the microbial community developed after 28 days. In an open-system simulation (flow-through experiment), the acetogenic Acetobacterium (49% relative abundance) and the sulfate reducer Desulfosporomusa (43% relative abundance) were the dominant genera. Whereas in the batch experiment, the sulfate reducers Desulfovibrio, Desulfomicrobium, and Desulfuromonas (95% relative abundance in total) were dominant. We also found evidence of enhanced mineral dissolution within the flow-through experiment, but there was little evidence of secondary deposits in the presence of biota. In contrast, SiO2 and Fe deposits formed within the batch experiment with biota but not under abiotic conditions. The results from these initial experiments indicate that different geochemical biosignatures can be generated between open and closed systems, and therefore, biosignature formation in open systems warrants further investigation. [ABSTRACT FROM AUTHOR]

Infilled walls and frames typically employ closely spaced rigid connection, which, under seismic actions, can lead to adverse effects such as amplified seismic responses, overall torsion, and the formation of weak layers in the structure. Flexible connection isolating the infilled walls from the frames can effectively mitigate the adverse effects of rigid connections. In order to reduce the structural mass and seismic impacts, Autoclaved Aerated Concrete (AAC) masonry flexible connection infilled walls have been widely researched. However, most AAC masonry flexible connection infilled walls require complex process operations for AAC blocks, which is not conducive to practical applications in engineering. Therefore, an AAC flexible connection infilled wall with Basalt Fiber Grating (BFG) strips instead of steel bars, with simplified process operations, has been proposed. Existing finite element models for BFG strip-reinforced AAC masonry flexible connection infilled walls employ solid elements, which are difficult to apply to large-scale structural simulations; moreover, existing simplified models for flexible connection infilled walls cannot simulate out-of-plane loading. In this paper, based on homogenization methods, using simplified elements to simulate components, a simplified model for the BFG strip-reinforced AAC masonry flexible connection infilled frame is proposed. Utilizing this model, stress analyses under both in-plane and out-of-plane loading are conducted and compared with corresponding experimental results. The results indicate that the in-plane simplified model (ISM) fits well with the experimental results in terms of hysteresis curves, with similar relationships between stiffness degradation and strength attenuation. The displacement force curve of the out-of-plane simplified model (OSM) before reaching the peak load is in good agreement with the experimental results. The maximum plastic range of OSM is 5% smaller than the test results, and it can be considered that the plastic ranges of the two are comparable, manifesting the models' capability to adequately manifest arching behavior. The simplified model enables simulation of out-of-plane loading and provides a new approach for modeling large-scale frame structures with flexible connection infilled wall. [ABSTRACT FROM AUTHOR]

Due to the small scale and short lifetimes of mode-2 internal solitary waves (ISWs), they are seldom observed by satellite images. This study investigated the optical remote sensing imaging characteristics of mode-2 ISWs through physical simulation experiments, proposed a method for identifying mode-2 ISWs in optical remote sensing images, and conducted multisource optical remote sensing observation of mode-2 ISWs in the northern South China Sea (SCS). We have gathered over 10 000 images from seven optical remote sensing satellites, including Terra/Aqua, Gaofen-1/6, HJ-2A/B, and CBERS-04. A total of 342 mode-2 ISWs events were identified, exhibiting primary concentrations near Dongsha Atoll and the northern Heng–Chun Ridge in the northeastern SCS, as well as the Shenhu–Yitong Shoals in the northwestern SCS. Most mode-2 ISWs were observed within the 150–400 m water depth range along the continental shelf. The mode-2 ISWs primarily propagate in a northwestern direction, with propagation speeds approximately half that of the mode-1 ISWs. In the case of the northern Heng–Chun Ridge, mode-2 ISWs tended to propagate in a southwest direction. This study underscores the significant potential of high-resolution optical remote sensing satellites in observing mode-2 ISW and provides a new direction for studying mode-2 ISW.

Copyright of Biology Teaching is the property of East China Normal University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The fatigue allowance effectively mitigates declines in physiological state due to work fatigue. An appropriate allowance rate facilitates timely recovery for employees and serves as a crucial basis for labor quota formulation. In this paper, the action mode in mechanical processing was extracted and disassembled into six action units. The study conducted fatigue measurement experiments based on physiological measurement methods, including exercise fatigue tests at different frequencies and work fatigue tests over varying durations. As the frequency of actions increased, the rate monotonic scheduling index showed a linear increasing trend and the degree of fatigue caused by the action was different. The fatigue coefficient of different action units and the fatigue index of the fatigue instability period were obtained by fitting. Hazard ratio indicators showed significant differences, and the corresponding fatigue recovery rest time was obtained for different continuous operation hours. By further fitting the above data, a fatigue relaxation rate model suitable for simulating operation methods was obtained (the fatigue coefficient for the simulated operations in this study is 0.076152) which could provide a reasonable basis for the formulation of fatigue allowance rates for machining methods.

This study investigates the extent to which victimization narratives in state information campaigns are an effective way to influence targeted external audiences. It focuses on two prolific users of information operations in opposition to the West, namely Russia and the People's Republic of China. In order to test whether the use of a victimization narrative increases the effectiveness of messaging in disinformation campaigns, the authors conducted dual experimental simulations on two samples of proxy target audiences. The experiment did not reveal any clear advantages in the use of a victimization narrative; rather there were indications (some of them statistically significant), that a victimization narrative could backfire. [ABSTRACT FROM AUTHOR]

Water level is crucial to the growth and development of wetland plants, in order to study the physiological and ecological responses of Pomatogeton crispus under different water levels, in the study, P. crispus were placed under 50 cm (control) and 60–135 cm water levels following a 15 cm gap gradient for 60 days in a simulation experiment. The results showed that: (1) As the water level gradient increased, the plant height, leaf number and biomass of P. crispus showed a trend of increasing and then decreasing. (2) The concentrations of chlorophyll a (Chl-a), chlorophyll b (Chl-b), chlorophyll a + b (Chl a + b) and carotenoids (Car) showed a multi-peak increasing trend with increasing water level, with the maximum values occurring in the 135 cm water level group. (3) The antioxidant enzymes of P. crispus showed a fluctuating upward trend with increasing water level, and the higher the water level the greater the difference within the group, and rooting activity of P. crispus was significantly increased under elevated water level conditions. (4) The P. crispus grows best in the water level range of 105 ∼ 120 cm, and the growth indexes such as the number of leaves and biomass all reach higher values in the water level of 105 ∼ 120 cm, If the water level is too high or too low, it has an effect on the growth and development of P. crispus.

[Objective] The flume simulation research on wave prevention and sand stabilization counter measures for coral sandy coastlines were studied in order to provide a theoretical basis for the project to protect coastlines against wave erosion along the Dengloujiao shoreline, located in the Xuwen National Coral Reef Nature Reserve on the Leizhou Peninsula, and to provide technical support for similar coastal areas. [Methods] The coastal erosion protection effect of san-dbag barrier measures was determined for the Dengloujiao coastline using a flume experiment simulation method. [Results] ① The composite effect of the overall structure of the diamond-shaped sand-bag barrier had a significant impact on the stability of the sand barrier. Two groups of sand barriers with a diameter of 5 cm or above was able to achieve self-stability. Calculated according to the gravity similarity criterion, this was equivalent to 50 cm diameter of the prototype; ② The sand-bag barrier achieved sediment fixation by increasing the roughness of the bed surface, weakening the hydrodynamic strength, and thereby reducing the intensity of sediment transport. As the diameter of the sand barrier increased, its shielding effect became more significant; ③ For a wave period of 1.90 s and a water depth of 0.4 m, the height of sand ridges observed in the experiment were 3—4 cm. Therefore, in practical projects, sand barriers with a diameter of 50 cm or more can prevent and control the migration of sand waves and sand ridges; ④ The sand barrier arranged in a diamond shape was less affected by oblique waves and had better stability than the sand barrier arranged in a normal direction. Therefore, it is advisable to use a diamond-shaped sand barrier to reduce the effect of oblique waves. [Conclusion] The use of sand-bag barriers as protective materials for coastal erosion not only achieved the goal of sand control, but also produced favourable ecological and environmental protection effects. These results could provide important scientific guidance and have significant and practical promotion value.

Explorative simulation experiment is an important mean to understand and study warfare, but it often faces problems such as high complexity of scenario sample space and explosion of space dimensions. To solve all above problems, a qualitative and quantitative method for screening experimental factors based on multi-label learning(MLL)is proposed. First, based on qualitative analysis, a pre-simulation experiment is designed and implemented, experimental data are collected and processed, and the problem of missing machine learning sample data is solved. Then, the input control layer is introduced to build a deep neural network, and sparse regularization is introduced to achieve feature selection during multi-label model training. Then, regression qualitative analysis is used to supplement and improve the experimental factors. Finally, the simulation of stereoscopic projection action is used for experimental verification. The experimental result shows that the method is feasible and valuable in military.

In modern industrial production, many advanced manufacturing technologies are constantly developing with the progress of social sciences. Welding, as an indispensable manufacturing technology in industrial production, has received close attention from various industries. High frequency welding technology is needed in fields such as mechanical manufacturing, machine making in the food industry, and intelligent robot model making. High frequency welding is an important technical means in the production process of welded pipes, and the level of welding temperature has a significant impact on the quality of welded pipe welds. This article studied the shortcomings of traditional high-frequency welding, analyzed the application method of nonlinear finite element method in high-frequency welding, and analyzed the dynamic process of welding and its influencing factors. The finite element method formula is used to stabilize the value of three-dimensional (3D) temperature field. This work studied the temperature distribution of welded pipe welding, welded pipe materials, inside and outside of welded pipe, and temperature changes under different voltages. The experimental results showed that the error value between the simulation results of the 3D temperature field of high-frequency welding and the measured experimental results was about 4.3542°C, which was basically similar, indicating the effectiveness of the 3D temperature field simulation experiment. With the development of science and technology, high-frequency welding technology would continue to improve, and the quality of welded pipe welds would become better and better with the progress of technology. The improvement in quality promotes the development and progress of industry, and maintains the quality of machine manufacturing. The simulation experiment method of 3D temperature field has shortened the experimental time and reduced the experimental cost, providing a new reference for other temperature related experiments.

In the context of global climate change, the frequency of waterlogging is increasing. Therefore, to elucidate the effects of waterlogging under real precipitation conditions on the physiological characteristics of peanuts and the underlying mechanics and to provide a theoretical basis for timely protective measures, this study involved a waterlogging disaster simulation experiment in the field environment and a waterlogging stress control experiment in the potting environment. It was found that sufficient water had a positive effect on the growth and development of peanuts (Arachis hypogaea L.) during the 3–5 days period at the beginning of waterlogging. However, as the duration of waterlogging increased, excess water inhibited the growth of peanuts, with a stronger inhibitory effect on the development of pods. A comparison of the two different experimental models found that in the potting environment, water circulation was not smooth, and the intensity of waterlogging was higher than in the field environment experiment, resulting in the effect of waterlogging being advanced by one observation stage (2 days) in the potting environment. Furthermore, using a novel fluorescence imaging system, an analysis of variations in the physiological characteristics of leaf sections demonstrated that the chlorophyll fluorescence in the leaves of the peanut plant exhibited a specific pattern in response to waterlogging stress.

This study investigates the coevolution of coauthorship and citation networks and their influence on scientific metrics such as the h-index and journal impact factors. Using a preferential attachment mechanism, we developed a model that integrated these networks and validated it with data from the American Physical Society (APS). While the correlations between reference counts, paper lifetime, and team sizes with scientific impact metrics are well-known, our findings demonstrate how these relationships vary depending on specific model parameters. For instance, increasing reference counts or reducing paper lifetime significantly boosts both journal impact factors and h-indexes, while expanding team sizes without adding new authors can artificially inflate h-indexes. These results highlight potential vulnerabilities in commonly used metrics and emphasize the value of modeling and simulation for improving bibliometric evaluations.

The purpose of this paper is the design of a potato drip irrigation tape recycling machine that would not require manual assistance or suffer from broken tapes. To clarify the recycling performance of the new potato drip irrigation tape recycling machine under different working parameters, a single-factor performance experiment was conducted. To investigate the reasons for variations in the performance indexes of the machine under different operating parameters, RecurDyn-EDEM coupled simulation experiments were carried out, with the peak height of soil and the maximum bending angle of the drip irrigation tape during the recycling process as the experimental indexes. To determine the optimal working parameter combinations and to clarify the effects of the interaction of various factors on the performance indexes, a response surface experiment was conducted. Following this, an analysis of variance was performed, and a mathematical regression model was established based on the experimental results. The findings revealed that a machine forward speed of 2.4 km/h, a shovel angle of 12°, and a conveyor sprocket speed of 270 r/min resulted in a drip irrigation tape recovery rate of 95.2%, meeting the relevant standards for drip irrigation tape recycling operations.

To address the challenges of indoor mold in southern China, this study designed and constructed an innovative experimental system to investigate mold growth in buildings under the combined influence of multiple factors. Using Fluent simulation (Ansys Fluent 19.0), we designed a suitably sized experimental chamber to realistically replicate the effects of factors such as temperature, humidity, and air velocity on mold growth. After establishing and fine-tuning the experimental system, we conducted two preliminary experiments, successfully validating the feasibility of our setup. Additionally, we observed that in a high-temperature, high-humidity environment of 28 °C and 80% relative humidity, the mold growth rate in the experimental chamber increased with the rise in inlet air velocity. This experimental system will serve as the foundation for future studies on indoor mold growth in building spaces in southern China.