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This article thoroughly assesses the Chemical Looping Hydrogen Production (CLHP) process, aiming to enhance understanding of detailed dynamic simulations. It includes a concise historical overview of chemical looping technology, emphasizing recent commercial applications like combustion engines. The article discusses several cases of pilot and sub-pilot scale investigations, along with critical insights to identify the issues surrounding the commercialization of this technology. Furthermore, the review is extended to analyze several aspects of the process to develop a dynamic simulation model, including reactants, operating modes, kinetic parameters, and the process models. Key process materials such as reduction fuel, oxygen carriers and solid supports are carefully chosen to achieve target conversions and net-zero carbon emissions. The three-reactor system is meticulously defined, focusing on closed-loop production's thermodynamic and economic benefits. Detailed information is provided on reactions within each unit and the required operating regimes for continuous solid circulation. The review also examines mathematical modeling methods for dynamic simulation implementation to determine gas-solid profiles at pellet and reactor scales. Simulations derived from this study's concepts can be refined through parameter modification for optimal process operation and control system analysis for real-world industrial applications. Ultimately, this review contributes significantly to the commercialization of CLHP, offering an economically viable solution for sustainable hydrogen production. [Display omitted] • Chemical looping is an economically viable solution for producing hydrogen fuel. • Dynamic models can further the knowledge of chemical looping hydrogen production. • Mathematical simulations can quantify the acclaimed advantages of the process. • Quantified results can drive further investment towards process industrialization. [ABSTRACT FROM AUTHOR]

The paper presents a case study in which a dynamic simulation modeling (DSM) calculation was carried out to assess the energy performance of a building in Giroc, a locality adjacent to the city of Timișoara, using the VABI Elements software. The characteristics were determined based on which the HVAC equipment was selected. [ABSTRACT FROM AUTHOR]

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This research introduces the NeuRaiSya (Neural Railway System Application), an innovative railway signaling system integrating deep learning for passenger analysis. The objectives of this research are to simulate the NeuRaiSya and evaluate its effectiveness using the GreatSPN tool (graphical editor for Petri nets). GreatSPN facilitates evaluations of system behavior, ensuring safety and efficiency. Five models were designed and simulated using the Petri nets model, including the Dynamics of Train Departure model, Train Operations with Passenger Counting model, Timestamp Data Collection model, Train Speed and Location model, and Train Related-Issues model. Through simulations and modeling using Petri nets, the study demonstrates the feasibility of the proposed NeuRaiSya system. The results highlight its potential in enhancing railway operations, ensuring passenger safety, and maintaining service quality amidst the evolving railway landscape in the Philippines. [ABSTRACT FROM AUTHOR]

The Cucumber Productivity Simulation Model (CPSM) was developed to precisely predict the dynamic process of cucumber productivity in a solar greenhouse. This research conducted a variety of sowing experiments and collected data on cucumber productivity and meteorological conditions from 2013 to 2015 and 2018 to 2020. Employing the principles of least squares, the relationship between cucumber productivity indicators and effective accumulated temperature (EAT) was fitted, determining key crop parameters and constructing the CPSM. Validation of the model was conducted using independent experimental data, evaluating its simulation accuracy. The results indicate that (1) CPSM can dynamically and meticulously simulate the formation process of different productivity indicators in cucumber. Normalized root mean square errors (NRMSE) ranged from 0.44% to 19.64%, and mean relative errors (MRE) ranged from 0.31% to 17.23% across different productivity indicator models. The models for organ water content, maximum root length, specific leaf area, and organ fresh weight distribution index demonstrated high simulation accuracy, while others showed relatively high accuracy. (2) Simulation accuracy varied with indicators and varieties. 19 indicators (34.55%) exhibited high simulation accuracy and 30 indicators (54.55%) showed relatively high accuracy. The JY35 variety (10.44 ± 8.49%) outperformed the JS206 variety (13.44 ± 8.50%) in terms of simulation accuracy. The JY35 variety had 39 superior productivity indicators (70.91%) while the JS206 variety had sixteen (29.09%). CPSM utilizes easily accessible temperature data as its input, allowing for precise and detailed simulation of productivity indicators for cucumber production in solar greenhouses. This research lays a theoretical foundation and provides technical support for guiding intelligent production management, efficient utilization of agricultural resources, and climate change productivity assessment in solar greenhouse cucumber production. [ABSTRACT FROM AUTHOR]

Effective relief reduces damages and protects people during natural disasters, such as earthquakes. This research proposes a data-driven model based on sustainability, taking into account the pre and post-crisis simultaneously. Real data was used to validate the model in various earthquake scenarios. The study addresses questions regarding the amount and allocation of relief goods during earthquakes. This research is carried out in two phases: simulation and modeling. The purpose of the simulation phase is to estimate the number of relief goods in different scenarios. Additionally, in the modeling phase, a data-based multi-objective model is presented, considering sustainability, to minimize the lack of relief goods, the number of untreated wounded, and supply chain costs. Using the dynamic simulation system, and after designing the structure of the earthquake effects on urban infrastructure, the actions and effects of the earthquake on vital arteries are investigated in different scenarios, and scenarios with a higher degree of risk are identified. The results showed that the highest and lowest demands for relief goods were related to the "Mosha-day fault" and "North Tehran-night fault" scenarios, respectively. [ABSTRACT FROM AUTHOR]

This study developed a finite element method (FEM) dynamic simulation to visualize the deployment behavior of thin membrane structures in the space environment. The proliferation of space debris resulting from accelerated space development threatens the future of space. Numerous researchers have explored strategies to prevent artificial structures from remaining in space and becoming space debris. One such method involves utilizing a drag sail device to de-orbit artificial structures, which reduces their kinetic energy by inducing additional atmospheric drag, allowing them to re-enter the Earth's atmosphere. Tohoku University and Nakashimada Engineering Works, Ltd. have successfully developed a deployable membrane structure for de-orbit purposes and demonstrated its effectiveness in space. Space structures, such as membranes, exhibit highly nonlinear behavior due to their flexible properties, and ground tests by actual devices cannot fully demonstrate their deployment stability in a microgravity environment. Therefore, evaluating the deployment behavior using simulation methods instead of relying solely on hardware development is crucial. In this study, we employed FEM to establish a simulation environment, which enables us to consider nonlinear oscillations of flexible structures, such as the membrane. The simulation results closely reproduce the deployment motion observed in ground tests by appropriately incorporating constraint conditions related to deployment forces and hardware interactions, such as a hub component initially wrapped by the membrane. The simulation facilitated an assessment of the impact of membrane properties on deployment without the need for physically developing an actual hardware device. We proposed evaluation methods for determining membrane properties in terms of the trend of propagation of deployed surface area and the tendency of deployment motion. This established simulation technique can be utilized to develop future flexible space structures. • De-orbit Membrane Mechanism (DOM) was developed as a satellite de-orbit application. • Formulate nonlinear FEM analysis of non-spin type deployable structures. • Modeling techniques of the membrane in simulation. • Evaluation of the membrane deployment between simulation and ground experiments. • Proposed methods can be used to predict the deployment behavior of the actual membrane. [ABSTRACT FROM AUTHOR]

The launcher recovery method known as 'In-Air Capturing' is an innovative approach where a winged rocket stage is captured mid-air by an aircraft and subsequently towed back to the launch site. To achieve this, a capturing device attached to a tether is released from the towing aircraft. This device autonomously connects the reusable launch vehicle to the aircraft, while the two vehicles are in proximity. The tether's flexible dynamics have a strong influence on the maneuverability of the capturing device. Thus, it is critical to model the dynamics of the tether to get a realistic understanding and to evaluate feasibility of the concept. However, precise modelling and control of highly flexible systems with large deformations is both challenging and computationally intensive. For engineering applications which involve closed-loop simulations, finding a trade-off between accuracy and computational effort is crucial. In this paper, the tether is modelled as a discretized chain of rigid bodies connected by rotational springs at the joints. The tether along with the capture system is integrated in a simulation model and open loop tests are performed to analyse the system characteristics. The tether properties are studied to find a suited configuration for 'In-Air Capturing'. • Multibody modelling approach for long cable like bodies with large deformation. • Capture system dynamics for the unique 'In-Air Capturing' launcher recovery concept. • Dynamic modelling for the complete capturing system including towing aircraft, capturing device and tether. • Assessment of tether properties suited for 'In-Air Capturing' with sensitivity studies. [ABSTRACT FROM AUTHOR]

Nonlinear dynamics plays a crucial role particularly in equipment validation of preparation production, validation results of which will significantly influence the results and period of drug registration in drug production processes. In this research, the flow field and temperature field simulation, calculation and analysis are creatively carried out in terms of depyrogenation tunnel, a very popular preparation drying-sterilization equipment in pharmaceutical processes with strong dynamic characteristics. After construction of 3D model of this equipment using Catia and mesh generation applying ANSYS, the computational fluid dynamic (CFD) method and verification of irrelevance method are carried out regarding 6.05 million of meshes to identify the flow velocity model and heat transfer model inside the equipment, to further provide methodology for pharmaceutical process validation and to further optimize the design of control methods. After calculation and simulation, the low-velocity vortices of different sizes inside the hood and the drying chamber are identified, which could cause vials to fall down; meanwhile, vials that are farther away from the outlet receives less heat exchange effect, which would shrink the effective sterilization area, indicating an inadequate validation methodology in pharmaceutical processes. [ABSTRACT FROM AUTHOR]

Agent-based models is a fundamental approach to untangle and study complex systems. Over the last decade, the need for more elaborate computing-demanding models has given rise to many frameworks and tools to run ABM simulations. Current state-of-the-art ABM tools focus either on ease of use, performance, or a trade-off between these two elements. Still, efficiency-oriented solutions (required for both large and small-scale simulations) are vulnerable to memory flaws which could invalidate experiment results. This work aims to merge efficiency, reliability, and safety under an innovative ABM software framework based on the Rust programming language. Our framework, krABMaga, is an open-source library that offers a high-level environment by exploiting meta-programming and expandable visualization features. We equipped our library with a dynamic simulation monitoring system and model exploration and optimization capabilities over parallel, distributed and cloud architectures. After presenting the overall architecture and functionalities of krABMaga, we compare our framework’s performance against the most widely adopted ABM software and the scalability potential of our simulation engine on a model calibration experiment running over an AWS EC2 virtual cluster machine. All code and examples models are available on GitHub. [ABSTRACT FROM AUTHOR]

Railway accidents, particularly serious derailments, can lead to catastrophic consequences. Therefore, it is essential to prevent derailment escalation to reduce the likelihood of severe derailments. Train post-derailment behaviours and containment methods play a critical role in preventing derailment escalation and providing passive safety protection and accident prevention in the event of a derailment. However, despite the increasing attention on this field from academia and industry in recent years, there is a lack of systematic exploration and summarization of emerging applications and containment methods in train post-derailment research. For this reason, this paper presents a comprehensive review of existing studies on train post-derailment behaviours, encompassing various topics such as post-derailment contact–impact models, dynamic modelling and simulation techniques, and the primary factors influencing post-derailment behaviours. Significantly, this review introduces and elucidates substitute guidance mechanisms (SGMs), which serve as railway-specific passive safety protection and accident prevention measures. The various types of SGMs are depicted, and their ongoing developments and applications are explored in depth. The review additionally points out several unresolved challenges including the adverse effects of SGMs, and proposes future research directions to advance the theoretical understanding and practical application of train post-derailment behaviours and containment methods. This review seeks to be a valuable reference for railway industry professionals in preventing catastrophic derailment consequences through post-derailment containment methods. [ABSTRACT FROM AUTHOR]

To further improve the simulation calculation ability of urban rail traction systems during the peak operation period and provide an accurate and reliable simulation tool for the subsequent train schedule and energy storage system design, a multi-train circuit model with a bilateral power supply was established in this paper, and a power calculation algorithm based on dynamic train density was designed. The circuit topology in the model can be dynamically adjusted according to the number of trains to improve the operation rate. Based on the spatial and electrical data of a real section of the subway, the urban rail circuit model was built on the MATLAB platform, and the actual operation data of the subway was imported for verification. The experimental results show that the multi-train model can accurately reflect the influence of voltage fluctuations on the traction system under different train running conditions, and the results fit the actual operation conditions. By comparing the influence of different train intervals on the RBE (regenerative braking energy) utilization, the results show that the optimal RBE utilization rate can be achieved by adjusting the train interval in the peak period. [ABSTRACT FROM AUTHOR]

The establishment of a high-fidelity simulation model for heating systems is crucial for practical guidance, as it serves predictive and evaluative purposes, offering accurate references for the operational management of actual engineering projects, thereby minimizing resource and cost wastage. This study, utilizing the Transient System Simulation Program (TRNSYS) software and focusing on an electric boiler water storage heating system in an elementary school, has developed a high-fidelity simulation model. Multiple TRNSYS (Types) modules were independently programmed, and the model's stability and precision were verified through error analysis. The model is capable of dynamically simulating the changes in supply and return water temperatures on both the storage and usage sides of the system under varying external environmental conditions and hydraulic states, achieving synchronous computation of the thermal and hydraulic characteristics of the heating system. The comparison and analysis of the temperature measurements at various system points against actual collected data revealed an average relative error of less than 5% across these measurements, indicating the simulation model's high accuracy and operational stability. It accurately and reliably reflects the thermal dynamics of the heating system, providing a reliable reference for practical application. This model is applicable for guiding the operational management of actual engineering projects and offers a scientific basis for subsequent system design and optimization. [ABSTRACT FROM AUTHOR]

Purpose: The dynamic modeling and simulation of a folding-link flexible manipulator based on the Bezier Interpolation Method (BIM) have been taken into consideration for investigation. Method: BIM is utilized to describe the deformation field of flexible links in which the coupling of the axial and transverse deformations are included. Lagrange equation is adopted in conjunction with the homogeneous transformation matrix to derive the dynamic equations of the flexible manipulator, and relevant dynamic constraint equations are also given. Several examples are presented to verify the accuracy and validity of the present dynamic modeling theory for the flexible manipulator. Results and Conclusion: BIM-based dynamic response of flexible manipulators are consistent with those based on Finite Element Method (FEM) and Assumed Mode Method (AMM). As a new discretization method of the deformable body, BIM can effectively describe the deformation field of flexible links, and it is also applicable to the dynamic modeling of multi-link flexible manipulators. The proposed dynamic equations can be improved to perfectly deal with the dynamic problem of flexible manipulators with folding links by adding constraint equations. Through the study of the dynamic characteristics of the right-angle folding-link manipulator under free fall, we can see that the steady state of the right-angle folding-link manipulator needs a long time, this shows that there is a more significant rigid-flexible coupling effect in the right-angle folding-link manipulator system. [ABSTRACT FROM AUTHOR]

With the penetration of distributed resources into power distribution networks, power distribution networks are transforming into active distribution networks with a high proportion of distributed generations and power electronic equipment. Efficient modeling and simulation methods are essential to perform dynamic response analysis. In order to satisfy the fast/steady/slow multiple time-scale simulation requirements of active distribution networks, a fast/medium/slow time partition model and a network decoupling method for short line characteristic lines is proposed in this paper. Through the decomposition coordination simulation method, the network is decomposed into multiple regions that can be simulated in parallel. Based on the interconnection of fiber optic network cards, a multi-rate parallel simulation and synchronization strategy is proposed, which significantly improves the simulation speed of active distribution networks while ensuring simulation accuracy. The numerical experiments have been conducted based on a modified IEEE 33-bus and a PG&E 69-bus, and simulation results show the feasibility of the proposed method. The verification results of the example show that using adaptive variable-step-size multi-rate parallel simulation technology can increase the subnet computation-time balance rate and simulation acceleration ratio to 119.90% and 121.31% in the same rate-parallel mode. [ABSTRACT FROM AUTHOR]

E-scooter vibrations are a problem recently studied. Theoretical models based on dynamic simulations and also real measurements have confirmed the high impact of e-scooter vibrations on driver comfort and health. Some authors recommend improving e-scooter damping systems, including tyres. However, it has not been suggested nor has any research been published studying how to improve e-scooter frame design for reducing driver vibrations and improving comfort. In this paper, we have modelled a real e-scooter to have a reference. Then, we have developed a multibody dynamic model for running dynamic simulations studying the influence of mass geometry parameters of the e-scooter frame (mass, centre of gravity and inertia moment). Acceleration results have been analysed based on the UNE-2631 standard for obtaining comfort values. Based on results, a qualitative e-scooter frame design guide for mitigating vibrations and increasing the comfort of e-scooter driver has been developed. Some application cases have been running on the multibody dynamic simulation model, finding improvements of comfort levels higher than 9% in comparison with the e-scooter reference model. The dynamic model has been qualitatively validated from real measurements. In addition, a basic sensor proposal and comfort colour scale is proposed for giving feedback to e-scooter drivers. [ABSTRACT FROM AUTHOR]

This paper aims to present two approaches for repeated-pole plus dead-time (RPPDT) models identification procedures for highorder processes based. First approach is based on using two or three points over the process reaction curve −an open-loop test− whereas the second approach is based on the use of the process relay control oscillating signals −a closed-loop test. Equations are provided for both model parameters identification as well as order estimation. Comparison tests confirm that the RPPDT models provide a better representation of the high-order process dynamics than its simple, usually employed, first-order approximation. These models are suitable for process representation in dynamic simulations and control system design studies. [ABSTRACT FROM AUTHOR]

In a rapidly evolving and often volatile crypto market, the ability to use historical data for simulations provides a more realistic assessment of how decentralized finance (DeFi) protocols might perform. This insight is crucial for participants, developers, and investors seeking to make informed decisions. This paper presents a comprehensive study evaluating the dynamic performance of a newly developed DeFi protocol—NOLUS. The main objective of this paper is to present and analyze the built realistic model of the platform. This model could be successfully used to analyze the stability of the platform under different environmental influences by performing various simulations and conducting experiments with different parameters that could not be realized with the real platform. In the article, the key components of the platform are presented in detail and the main dependencies between them are clarified, in addition to the ways of forming multiple variables, and the complex relations between them in the real protocol are explained. The main finding from the experimental part of the study is that the performance of the protocol representation accounts for the expected system behavior. Hence the system simulation could be successfully used to reveal essential protocol behaviors resulting from potential shifts in the crypto market environment and to optimize the protocol's hyper parameters. [ABSTRACT FROM AUTHOR]

The study of crude oil oxidation characteristics is fundamental to the design of ignition in situ combustion. Experimentation is the most crucial method for studying the oxidation characteristics of crude oil. Aiming to address the challenges posed by high temperature, high pressure, and rapid temperature changes during the combustion of crude oil, a dynamic simulation system for high-temperature and high-pressure ignition is designed. In order to study the oxidation characteristics of the crude oil ignition process, we conducted experiments using a high-temperature and high-pressure dynamic ignition simulation device. The experiments focused on determining the ignition point of crude oil under different pressure conditions, oil–water ratios, heating rates, gas injection rates, and other relevant characteristics. The kinetic model for the oxidation process of crude oil ignition was established. The kinetic parameters were calculated for different ignition conditions and the apparent activation energy for each oxidation stage was determined. Additionally, the stability of in situ combustion was evaluated under various ignition parameters. The results show that the Arrhenius curves for crude oil exhibit noticeable differences in the HTO (high-temperature oxidation) and LTO (low-temperature oxidation) regions. The curves demonstrate good linearity in the HTO region, with correlation coefficients exceeding 0.9. Moreover, the apparent activation energies in the HTO region range from 8.01 to 26.7 kJ/mol. The apparent activation energies and finger front factors were calculated for the HTO stage under different pressure conditions. The results showed that, as the pressure increased, the autoignition point, inflection point temperature, and apparent activation energy of the crude oil decreased. This suggests that increasing the pressure can enhance the HTO of the crude oil. The spontaneous ignition point of the crude oil exhibited an upward trend as the heating rate increased. Additionally, the maximum temperature during the combustion process generally increased with the heating rate, reaching a maximum temperature of 453.1 °C. The tests demonstrated that the simulation system is capable of real-time monitoring and recording of oxidation parameters during the combustion process of crude oil. This system can provide essential data for project implementation and numerical simulation. [ABSTRACT FROM AUTHOR]

This document is a summary of a special issue of the journal Mathematics, titled "Mathematical Modeling and Simulation in Mechanics and Dynamic Systems, 2nd Edition." The special issue focuses on the development of sophisticated models to predict phenomena in dynamic systems using experiments and computer models. The issue includes papers on topics such as modeling mechanical systems, new methods in dynamic systems, and the behavior simulation of mechanical systems. The papers were written by authors from 13 different countries, and the majority of the articles adhere well to the theme of the special issue. The document also provides a table showing the geographic distribution of authors by country. The authors of the special issue have made significant contributions to the field, and the document concludes by stating that the authors have no conflicts of interest. [Extracted from the article]

The paper considers the development and application of digital twins for nuclear power facilities with the purpose of improving operational safety and cost efficiency. The TERMIT technology for automated simulation is presented to develop comprehensive calculation models of various classes and purposes for full-scale simulation of dynamic processes occurring in nuclear power facilities. The main directions and results of the technology application are provided. [ABSTRACT FROM AUTHOR]

• The optical fiber coil with spool (OFCS) is a crucial tool for precise physics measurements. • To improve the seismic resistance of OFCSs in space applications, the vibration modes are thoroughly investigated through dynamic analysis, simulations, and experiments. • We establish a dynamic model of the OFCS based on the vibration transmission mechanism to characterize its vibration modes. • The vibration eigenfrequency and shapes are calculated under various conditions. • The experimental results validate the feasibility of the dynamic model and simulation, meanwhile, the discrepancies between the simulations and experiments are analyzed. • This study is the first of its kind to develop a comprehensive dynamic model for an OFCS, with simulations and experiments confirming its effectiveness. The optical fiber coil with spool (OFCS) is a crucial tool for precise physics measurements. To improve the seismic resistance of OFCSs in space applications, the vibration modes are thoroughly investigated through dynamic analysis, simulations, and experiments. We establish a dynamic model of the OFCS based on the vibration transmission mechanism to characterize its vibration modes. The vibration eigenfrequency and shapes are calculated and simulated under various conditions. The experimental results validate the feasibility of the dynamic model and simulation, meanwhile, the discrepancies between the simulations and experiments are analyzed. This study is the first of its kind to develop a comprehensive dynamic model for an OFCS, with simulations and experiments confirming its effectiveness. [ABSTRACT FROM AUTHOR]

• A plant-wide model is presented for continuous biomanufacturing benchmarking. • The model includes a tailored control strategy for dynamic simulation performance. • Realistic sensors and actuators consider measurement's noise and lag time. • Case study framework and examples are provided for user guidance. The pharmaceutical industry's shift towards biological therapeutics has led to a transition from conventional batch production to continuous manufacturing. This change highlights the crucial need for effective process monitoring and control strategies to ensure consistent product quality and stability. Open-source benchmark simulation models have become essential tools for refining these processes, offering a platform for testing research hypotheses. This study uses the production of Lovastatin as a case study for continuous biopharmaceutical production. A comprehensive dynamic model covering upstream and downstream components provides an integrated perspective of the production process. The study introduces a basic control system emphasizing realistic sensor and actuator integration to enhance simulation accuracy. It assesses the benchmark through open-loop and closed-loop simulations, offering an in-depth analysis of the KTB1 model's dynamic response and functionality. KTB1 represents a model-driven decision support tool that enables the evaluation of monitoring strategies, process design, process optimization, and control for biomanufacturing. [ABSTRACT FROM AUTHOR]

Dynamic simulation is a powerful tool for accurately evaluating the thermal demands of buildings and assessing the impact of energy refurbishment actions on their final consumption. Conversely, semi-stationary models are widely adopted in commercial applications for its simplified approach, which reduce calculation times, resulting in standardized results showing a certain deviation with respect to the real energy This paper presents the energy and economic comparison between the dynamic simulation and semi-stationary approaches for the calculation of primary energy demand of residential buildings. The semi-stationary method, used by the legislation to calculate the buildings energy label, is based on an energy performance parameter, not representative of the real energy demand. Conversely, an approach based on dynamic simulation provides a more reliable estimation of the primary energy demand. The main novelty of this paper is to numerically prove that the energy and economic savings calculated by means of software based on the current legislation may be overestimated. In this work, the dynamic simulation of the building-plant system is performed by TRaNsient SYstem Simulation (TRNSYS) program. Each building apartment is divided in thermal zones, where the internal heat gains are defined in detail. The semi-stationary simulation of the building-plant system is performed according to the Italian standard UNI TS 11300. The models allow one to evaluate the yearly primary energy demand, along with the energy bill and CO 2 emissions. A specific case study is developed for a residential building located in Naples (Italy). The models are used to calculate the building energy demand for several scenarios, considering different thermal transmittances of the building elements. The results show that the semi-stationary method overestimates of primary energy saving, equal to 64.7 %, with respect to the one calculated with the dynamic approach, equal to 43.2 %. • Semi-stationary and dynamic simulations were compared for residential buildings. • Critical evaluation of energy and economic savings due to the building refurbishment. • Primary energy savings of 65 % and 43 % by semi-stationary and dynamic simulation. • Dynamic simulation is needed within the legal frame of energy efficient buildings. [ABSTRACT FROM AUTHOR]

Understanding the dynamic interaction between smallholder farmers' adaptation decision-making behavior and the policy environment in the context of human-induced disasters is vital for developing effective policies to enhance farmers' participation in disaster risk reduction (DRR). From the perspective of bounded rationality theory, this study constructs the farmer-land-policy interaction (FLPI) model, taking Heifangtai in Loess Plateau, China, as a case study. Based on first-hand micro data, this study combines static econometric model analysis with dynamic simulation techniques, achieving a combination of micro decision-making and macro policies to understand the interaction between farmers and the policy environment. The FLPI model simulates farmers' future adaptations under multiple policy scenarios (baseline, mandatory policy, and subsidy policy scenario with a combination of different policy tools) from 2021 to 2030. Compared with the simulation results of the baseline scenario, the results indicate that mandatory and subsidy policies are effective interventions incentivizing farmers' adaptation behavior for effective DRR. Mandatory policies rely on policy intervention to ensure that farmers adopt drip irrigation and to promote the generation of long-term behavior of farmers. And the results also propose a suitable subsidy range of 700–900 yuan and with a period of more than 2 years for subsidy policy. This study enriches the research on the interaction simulation between farmer behavior and policy environment under the background of human-induced disasters. And the FLPI model uses survey data as input, which could provide behavior rules closer to real situations than that of simplifying assumptions. The research indicates that the "bottom-up" approach of the FLPI model proven more appropriate to presenting micro-level adaptation and dynamic changes than traditional statistical models.And the agent-based model is very suitable for simulating the behavioral decision-making changes of farmers in policy environments. • ABM of farmers' adaptation to irrigation-induced landslides. • ABM framework based on bounded rationality theory and empirical data. • Scenario analysis for simulating the effectiveness of policy intervention. • Pro-environmental values and peer effect influence farmers' adaptation. • Appropriate policy intervention improves farmers' adaptation. [ABSTRACT FROM AUTHOR]

In this paper, a novel numerical simulation approach based on the finite element method for dynamically modeling the excavation process of shield tunneling is proposed, with the shield-ground interactions well captured. This method is capable of mimicking the alternating modes of advancing and stopping of a shield boring machine during underground construction, with the important effects of the cutterhead rotation and slurry support pressure considered. Under the cutting action, the soil at the excavation face would experience irreversible deformation and damage, such that additional support needs to be provided by the cutterhead blades and slurry to maintain stability. The impacts of key construction parameters are examined, including cutterhead rotary speed, advance rate, and slurry support pressure, on shield tunneling operations and ground responses. The numerical model is rigorously validated against physical model experiments. This work provides useful insights into the mechanistic processes in the stratum during shield tunneling, including the spatiotemporal evolution of ground deformation patterns and stress redistributions. The results offer valuable guidance for optimizing shield tunneling operations and enhancing tunneling safety and efficiency. [ABSTRACT FROM AUTHOR]

This paper presents a modeling and simulation study of dynamic compression behavior of Bulk Metallic Glasses (BMGs) at room and elevated temperatures using the split Hopkinson pressure bar (SHPB) setup. The primary objective of this study is to develop and validate a constitutive model and simulation methodology capable of predicting the high strain rate response of BMGs at different temperatures. We propose a constitutive model for BMGs that accounts for the effects of high strain rates and elevated temperatures. We numerically implemented this model in ABAQUS/Explicit Finite Element Analysis software by writing a Vectorized User Material (VUMAT) subroutine. The methodology for modeling and simulation of dynamic compression of BMG specimens using the SHPB setup is developed. The present simulations are able to correctly predict the rate-independent response of Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 (Vitreloy-1) BMG under dynamic compression at room and elevated temperatures. Furthermore, the present simulations are also able to correctly predict the negative strain rate sensitivity (SRS) of Zr 52.5 Cu 17.9 Ni 14.6 Al 10 Ti 5 (Vitreloy-105) BMG at room temperature. Finally, the present simulations correctly predict that the failure stress of Zr 64.13 Cu 15.75 Ni 10.12 Al 10 BMG decreases with increasing temperature and exhibits a minimal positive SRS. The present study is the first successful attempt to model the mechanical response of various BMGs under dynamic compression and at room and elevated temperatures. In particular, the experimentally observed negative SRS in some BMGs has been successfully simulated. The present work has important implications for the design of next generation spacecraft shields that are based on BMGs for mitigating the effects of hypervelocity impacts from debris in space. • Developed a modeling and simulation methodology for dynamic compression of BMGs using the SHPB setup • Proposed and validated a new constitutive model for BMGs for high strain rates and elevated temperatures • The rate-independent response of Vitreloy-1 BMG is correctly predicted by the model • The negative strain rate sensitivity of Vitreloy-105 BMG is accurately captured by the model • Mild positive strain rate sensitivity of Zr 64.13 Cu 15.75 Ni 10.12 Al 10 BMG at elevated temperatures is also accurately reproduced by the model [ABSTRACT FROM AUTHOR]

The landing airbag system, a mechanism composed of thin-walled structures, is designed to ensure the safe landing of a lander. To investigate the dynamic behavior of the landing airbag with large deformations, a novel modeling approach incorporating gas exchange and frictional contact is proposed. The Absolute Nodal Coordinate Formulation (ANCF) is introduced to model the flexible airbag. Subsequently, the gas parameters inside the airbag are calculated by integrating the Control Volume (CV) Method and the energy conservation equation. Additionally, based on master–slave techniques, a frictional contact formulation for the thin-walled structure and the rigid plane is presented, in which the normal contact force is estimated using the penalty method, and the velocity-based friction model accounting for the stick–slip transition characterizes the tangential friction. Furthermore, the bounding box technology is adopted to improve contact detection efficiency. A series of numerical examples are performed, which demonstrates the proposed model's advantages in terms of precision and versatility. Finally, the landing dynamic characteristics of the airbag landing system for the small lunar lander are successfully revealed, and the parameter analysis for the airbag system is expected to aid the design optimization of the airbag cushioning system. • A model with good convergence and precision for pneumatic membranes is established. • The control volume method with energy conservation is used to describe gas states. • The approach considering the stick–slip transition is used for the friction. • The landing dynamic characteristics of the small lunar lander are revealed. [ABSTRACT FROM AUTHOR]