Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

Article Types

Countries / Regions

Search Results (89)

Search Parameters:
Keywords = bond-fluctuation model

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
13 pages, 3937 KiB  
Article
Vanillin Quantum–Classical Photodynamics and Photostatic Optical Spectra
by Vladimir Pomogaev and Olga Tchaikovskaya
ChemEngineering 2025, 9(4), 76; https://doi.org/10.3390/chemengineering9040076 - 23 Jul 2025
Viewed by 209
Abstract
Vanillin photoinduced deprotonation was evaluated and analyzed. Vibronic states and transitions were computationally investigated. Optimizations and vertical electron transitions in the gas phase and with the continuum solvation model were computed using the time-dependent density functional theory. Static absorption and emission (photostatic optical) [...] Read more.
Vanillin photoinduced deprotonation was evaluated and analyzed. Vibronic states and transitions were computationally investigated. Optimizations and vertical electron transitions in the gas phase and with the continuum solvation model were computed using the time-dependent density functional theory. Static absorption and emission (photostatic optical) spectra were statistically averaged over the excited instantaneous molecular conformers fluctuating on quantum–classical molecular dynamic trajectories. Photostatic optical spectra were generated using the hybrid quantum–classical molecular dynamics for explicit solvent models. Conical intersection searching and nonadiabatic molecular dynamics simulations defined potential energy surface propagations, intersections, dissipations, and dissociations. The procedure included mixed-reference spin–flip excitations for both procedures and trajectory surface hopping for photodynamics. Insignificant structural deformations vs. hydroxyl bond cleavage followed by deprotonation were demonstrated starting from different initial structural conditions, which included optimized, transition state, and several other important fluctuating configurations in various environments. Vanillin electronic structure changes were illustrated and analyzed at the key points on conical intersection and nonadiabatic molecular dynamics trajectories by investigating molecular orbital symmetry and electron density difference. The hydroxyl group decomposed on transition to a σ-molecular orbital localized on the elongated O–H bond. Full article
Show Figures

Figure 1

16 pages, 7058 KiB  
Article
Function and Engineering of a Food Enzyme Under Coupled High-Temperature–Pressure Conditions: Insights from Molecular Dynamics Simulation and Experimental Validation
by Zidan Liu, Weihao Long, Keying Chen, Linyu Luo, Qiong Li, Tolbert Osire, Nan Zheng and Mengfei Long
Foods 2025, 14(14), 2485; https://doi.org/10.3390/foods14142485 - 16 Jul 2025
Viewed by 358
Abstract
The relationship between protein structure and function is intrinsically interconnected, as the structure of a protein directly determines its functional properties. To investigate the effects of temperature and pressure on protein function, this study employed ethyl carbamate (EC) hydrolase as a model food [...] Read more.
The relationship between protein structure and function is intrinsically interconnected, as the structure of a protein directly determines its functional properties. To investigate the effects of temperature and pressure on protein function, this study employed ethyl carbamate (EC) hydrolase as a model food enzyme and conducted molecular dynamics (MD) simulations under varying temperature and pressure levels to elucidate its structure–function relationship. By systematically analyzing the dynamic changes in root mean square deviation (RMSD), root mean square fluctuation (RMSF), radius of gyration (Rg), solvent accessible surface area (SASA), hydrogen bonding, catalytic pocket conformation, and packing density under different temperature and pressure conditions, we revealed the structural adaptability of EC hydrolase. Furthermore, we analyzed the characteristics of EC hydrolase using molecular dynamics simulations with temperature and pressure levels, as well as conformational bias-based computer-aided engineering, providing both theoretical and experimental foundation for the adaptability mechanisms of enzymes under extreme conditions. Full article
(This article belongs to the Section Food Quality and Safety)
Show Figures

Figure 1

16 pages, 4649 KiB  
Article
Rapid Two-Step Isolation of Kaempferol from the Hosta plantaginea Flower and Its Anti-Inflammatory Mechanism: Evidence from Network Pharmacology, Molecular Docking, Molecular Dynamics Simulation, and Experimental Validation
by Yating Yang, Bowei Xia, Huan Ouyang, Junyu Guo, Qingya Hu, Li Yang and Junwei He
Separations 2025, 12(6), 138; https://doi.org/10.3390/separations12060138 - 23 May 2025
Cited by 1 | Viewed by 380
Abstract
The rapid isolation of target constituents from natural products poses a significant challenge and is a key focus in current research. The Hosta plantaginea flower (HPF), a traditional Chinese medicinal herb, is primarily used to treat inflammatory diseases, with kaempferol as one of [...] Read more.
The rapid isolation of target constituents from natural products poses a significant challenge and is a key focus in current research. The Hosta plantaginea flower (HPF), a traditional Chinese medicinal herb, is primarily used to treat inflammatory diseases, with kaempferol as one of its major bioactive constituents. In this study, macroporous adsorption resin was used to purify total flavonoids (TF) from the HPFs. The 50% ethanol–water elution fraction of the TF was then recrystallized to yield kaempferol with a purity of 99.44%. Network pharmacology analysis identified 61 potential kaempferol-inflammation targets, which were linked to the PI3K-Akt and TNF signaling pathways. Molecular docking and molecular dynamics simulations revealed the stability and binding of kaempferol to PI3K, Akt, and TNF-α proteins. The analysis metrics included binding ability, the root mean square deviation (RMSD), radius of gyration, free energy landscape, solvent-accessible surface area, hydrogen bond count, RMS fluctuation, free binding energy, amino acid residue free energy decomposition, and principal component analysis. The anti-inflammatory mechanism of kaempferol was further validated in an LPS-induced RAW264.7 cell model, where it was shown to inhibit the PI3K-Akt and TNF-α signaling pathways. This study provides new insights into the anti-inflammatory mechanism of kaempferol and presents novel strategies for the rapid isolation of target constituents from natural products. Full article
Show Figures

Figure 1

16 pages, 28451 KiB  
Article
Thermo-Mechanical Weathering in Malan Loess Under Thermal Shocks
by Yangqing Gong, Yanrong Li and Shengdi He
Sensors 2025, 25(10), 3115; https://doi.org/10.3390/s25103115 - 14 May 2025
Viewed by 378
Abstract
Extreme climatic conditions characterized by drastic temperature fluctuations exacerbate soil erosion through intensified thermo-mechanical weathering processes. Loess-covered regions are particularly vulnerable to such conditions because of the inherent thermo-sensitivity of loess. A comprehensive investigation of mechanisms of thermo-mechanical weathering in loess under extreme [...] Read more.
Extreme climatic conditions characterized by drastic temperature fluctuations exacerbate soil erosion through intensified thermo-mechanical weathering processes. Loess-covered regions are particularly vulnerable to such conditions because of the inherent thermo-sensitivity of loess. A comprehensive investigation of mechanisms of thermo-mechanical weathering in loess under extreme temperature regimes holds critical importance for elucidating soil degradation patterns. It is also essential for formulating mitigation strategies in climate-sensitive loess terrains, especially given the increasing frequency of extreme weather events under global warming scenarios. This study employed integrated physical monitoring experiments and numerical modeling. The evolutionary patterns of temperature fields and corresponding thermal stress distributions in loess subjected to both heat shock (rapid heating) and cold shock (rapid cooling) conditions were systematically examined. The key findings are as follows: (1) Soil temperature variations demonstrate phase-lagged responses to ambient thermal variations during both shock scenarios, exhibiting distinct thermal inertia effects. (2) The spatial distribution pattern of thermal stress is predominantly governed by the temperature gradient within the soil matrix. (3) While the magnitude ranges of thermal stress remain comparable between shock types, their directional characteristics fundamentally differ; heat shocks induce surface compressive stresses and internal tensile stresses, whereas cold shocks generate inverse stress patterns. (4) Compared to heat shock, cold shocks trigger obvious surface degradation through tensile stress-induced failure of particle bonds. These mechanically weakened zones establish favorable conditions for subsequent erosion processes in loess landscapes. Full article
(This article belongs to the Section Physical Sensors)
Show Figures

Figure 1

16 pages, 18350 KiB  
Article
Modification of Equation for Calculating the Bond Stress Between Steel Bars and Concrete
by Xiaosan Yin, Jimin Li, Shidong Tang, Yuzhou Sun and Md. Mashiur Rahman
Buildings 2025, 15(7), 1174; https://doi.org/10.3390/buildings15071174 - 3 Apr 2025
Viewed by 604
Abstract
The bond between steel bars and concrete is a fundamental aspect of reinforced concrete, ensuring the efficient transfer of forces between the two materials and guaranteeing their compatibility and composite action. The conventional equation for calculating bond stress does not account for slip [...] Read more.
The bond between steel bars and concrete is a fundamental aspect of reinforced concrete, ensuring the efficient transfer of forces between the two materials and guaranteeing their compatibility and composite action. The conventional equation for calculating bond stress does not account for slip effects. However, significant slip can lead to considerable errors, which are disadvantageous when analyzing bond performance using finite element methods. To address this issue, this study proposed a modified bond stress calculation model, whose reliability was systematically validated through pull-out tests and comparative analysis with a CEB-FIP model. The experimental program employed a universal testing machine for load application, with a static strain measurement system continuously monitoring stress–strain data throughout the loading process. The experimental results indicated that the failure process of the specimens could be categorized into the following, four distinct stages: micro-slip stage, slip stage, descent stage, and residual stage. The discrepancy between bond stresses calculated by the modified and conventional equations increased with the increasing relative slip, reaching its maximum value in the residual stage. A comparative analysis of 23 groups of experimental data from the literature was performed, revealing that the difference in bonding stress reached a maximum of 20.45% in the residual stage, with a standard deviation (S) of 0.006 and a coefficient of variation (Cv) of 0.321, reflecting small fluctuations but large dispersion. In contrast, the S of the residual bonding stress was 0.016, and the Cv was 0.080, showing lower dispersion but greater volatility. Further comparison with the CEB-FIP model confirmed the superior applicability and computational accuracy of the proposed modified model. Therefore, the modified equation should be utilized for calculating bond stress when significant slip occurs, particularly during the residual stage. Full article
(This article belongs to the Section Building Structures)
Show Figures

Figure 1

29 pages, 2787 KiB  
Article
Asymmetric Shocks and Pension Fund Volatility: A GARCH Approach with Macroeconomic Predictors to an Unexplored Emerging Market
by Cristiana Tudor, Aura Girlovan, Gabriel Robert Saiu and Daniel Dumitru Guse
Mathematics 2025, 13(7), 1134; https://doi.org/10.3390/math13071134 - 30 Mar 2025
Viewed by 1046
Abstract
Financial stability analysis requires volatility modeling, especially in emerging nations where pension fund systems are very vulnerable to macrofinancial risks. In order to examine the volatility dynamics of Romania’s private pension system, this study uses daily net asset value (NAV) data from 2012 [...] Read more.
Financial stability analysis requires volatility modeling, especially in emerging nations where pension fund systems are very vulnerable to macrofinancial risks. In order to examine the volatility dynamics of Romania’s private pension system, this study uses daily net asset value (NAV) data from 2012 to 2024 to evaluate four GARCH-type models: standard GARCH (sGARCH), exponential GARCH (EGARCH), Glosten–Jagannathan–Runkle GARCH (GJR-GARCH), and component GARCH (C-GARCH). The analysis includes domestic and international equity indices (BET, STOXX), government bond yields (ROMGB 10Y, ROMANI 5Y), short-term interbank rates (ROBOR ON), and exchange rate fluctuations (RON/EUR). Current findings indicate that EGARCH captures asymmetric fluctuations in pension fund performance, where positive shocks generate larger increases in volatility than negative ones, highlighting an atypical asymmetry pattern. Furthermore, the stabilizing effects of government bonds are overshadowed by stock market behavior, which becomes the primary driver of risk. Fluctuations in exchange rates further increase volatility, especially in markets vulnerable to external disturbances. The findings offer empirical evidence for the necessity of more cautious risk management approaches and highlight the importance of regulatory oversight in maintaining market confidence. The study underscores the importance of customized allocation frameworks that reduce vulnerability to disruptive events while maintaining prospects for sustained growth. This new dataset contributes to enhancing the comprehension of pension fund volatility within the context of emerging markets. These insights can assist managers and policymakers seeking to fortify retirement outcomes. Full article
(This article belongs to the Section E5: Financial Mathematics)
Show Figures

Figure 1

12 pages, 3859 KiB  
Article
Chain Size and Knots of Ring Polymers in All-Crossing and Intra-Crossing Melts
by Jiangyang Mo, Jingqiao Guo, Xue Yu, Jianlei Yang, Guodong Hu, Jianhui Xin, Mengxia Yan, Yuan Wang, Yongjie Mo, Yuxi Jia, Lianyong Wu and Yongjin Ruan
Polymers 2025, 17(7), 854; https://doi.org/10.3390/polym17070854 - 23 Mar 2025
Viewed by 510
Abstract
Using dynamic Monte Carlo simulations based on the bond-fluctuation model, we systematically investigated the size and knots of ring polymers in all-crossing systems and intra-crossing systems. Our results demonstrate that the interchain constraint can increase the knotting probability, but does not alter the [...] Read more.
Using dynamic Monte Carlo simulations based on the bond-fluctuation model, we systematically investigated the size and knots of ring polymers in all-crossing systems and intra-crossing systems. Our results demonstrate that the interchain constraint can increase the knotting probability, but does not alter the scaling relationship between knotting probability and chain length for ring polymers in melts. Having established that, we derived the interchain constraint contribution to the free energy of ring polymers in intra-crossing systems based on the knotting probability and obtained the scaling relationship between the size R and chain length N, i.e., R~N1/6. And, by calculating the mean-squared radius of gyration of ring polymers in intra-crossing systems, we validated these scaling results. Finally, we analyze the size of knotted ring polymers with different types and compare corresponding scaling exponents for size versus chain lengths of ring polymers with different knotting complexities. These results provide fundamental insights into the static properties of ring polymers in melts. Full article
(This article belongs to the Special Issue Computational Modeling and Simulations of Polymers)
Show Figures

Figure 1

17 pages, 13141 KiB  
Article
A Temperature-Independent Gate-Oxide Degradation Monitoring Method for Silicon Carbide Metal Oxide–Semiconductor Field-Effect Transistors Based on Turn-Off Ringing
by Xinghao Zhou, Pengju Sun, Kaiwei Li, Qingsong Liu, Lan Chen and Bo Wang
Electronics 2025, 14(4), 771; https://doi.org/10.3390/electronics14040771 - 16 Feb 2025
Viewed by 988
Abstract
Gate-oxide degradation in silicon carbide (SiC) metal oxide–semiconductor field-effect transistors (MOSFETs) is a significant concern. Consequently, several methods have been developed to monitor the aging degree. In this article, a temperature-independent method for gate-oxide degradation monitoring is proposed by measuring the minimum turn-off [...] Read more.
Gate-oxide degradation in silicon carbide (SiC) metal oxide–semiconductor field-effect transistors (MOSFETs) is a significant concern. Consequently, several methods have been developed to monitor the aging degree. In this article, a temperature-independent method for gate-oxide degradation monitoring is proposed by measuring the minimum turn-off circuit parasitic inductor voltage vcir_min at a specific gate resistor and voltage. The temperature sensitivity of vcir_min is analyzed based on a derived model. Adjustment of the turn-off gate voltage and resistance is proposed to mitigate the impact of temperature on vcir_min. The devices under test are aged by high-temperature gate bias (HTGB) experiments and are tested in double-pulse tests (DPT). A 32 V bias for 42 h and 25–150 °C temperature results in changes of 6.55% and 0.103% in vcir_min, respectively. The experimental results show that the proposed method is effective in maintaining temperature independence. Additionally, the effects of bus voltage, load current, and bond wire failure on vcir_min are also tested and analyzed. The proposed method provides a valuable tool for accurately monitoring SiC MOSFET gate-oxide degradation in scenarios characterized by significant temperature fluctuations. Full article
Show Figures

Figure 1

21 pages, 5970 KiB  
Article
A Comparative Molecular Dynamics Study of Food-Derived Compounds as PD-L1 Inhibitors: Insights Across Six Flavonoid Subgroups
by Dejun Jiang, Hyuk-Ku Kwon, Oh Wook Kwon and Youngjin Choi
Molecules 2025, 30(4), 907; https://doi.org/10.3390/molecules30040907 - 15 Feb 2025
Cited by 1 | Viewed by 1113
Abstract
In this study, we investigated the inhibitory potential of 60 flavonoids from six distinct subgroups on the programmed cell death ligand 1 (PD-L1) dimer through molecular docking and dynamics simulations. Using AutoDock Vina for docking, the binding poses and affinities were evaluated, revealing [...] Read more.
In this study, we investigated the inhibitory potential of 60 flavonoids from six distinct subgroups on the programmed cell death ligand 1 (PD-L1) dimer through molecular docking and dynamics simulations. Using AutoDock Vina for docking, the binding poses and affinities were evaluated, revealing an average binding affinity of −8.5 kcal/mol for the flavonoids. Among them, ginkgetin exhibited the highest binding free energy of −46.73 kcal/mol, indicating a strong interaction with PD-L1, while diosmin followed closely, with −44.96 kcal/mol. Molecular dynamics simulations were used to further elucidate the dynamic interactions and stability of the flavonoid–PD-L1 complexes, with the analyses showing minimal root mean square deviation (RMSD) and favorable root mean square fluctuation (RMSF) profiles for several compounds, particularly formononetin, idaein, and neohesperidin. Additionally, contact number and hydrogen bond analyses were performed, which highlighted ginkgetin and diosmin as key flavonoids with significant binding interactions, evidenced by their stable conformations and robust molecular interactions throughout the simulations. Ultimately, a cell-based assay confirmed their ability to inhibit the proliferation of cancer cells. These results, validated through cell-based assays, indicate that the strategy of identifying natural compounds with anticancer activity using computational modeling is highly effective. Full article
(This article belongs to the Special Issue Functional Foods and Dietary Bioactives in Human Health)
Show Figures

Graphical abstract

24 pages, 4942 KiB  
Article
Identification and Localization Study of Grounding System Defects in Cross-Bonded Cables
by Qiying Zhang, Kunsheng Li, Lian Chen, Jian Luo and Zhongyong Zhao
Electronics 2025, 14(3), 622; https://doi.org/10.3390/electronics14030622 - 5 Feb 2025
Viewed by 705
Abstract
Cross-bonded cables improve transmission efficiency by optimizing the grounding method. However, due to the complexity of their grounding system, they are prone to multiple types of defects, making defect state identification more challenging. Additionally, accurately locating sheath damage defects becomes more difficult in [...] Read more.
Cross-bonded cables improve transmission efficiency by optimizing the grounding method. However, due to the complexity of their grounding system, they are prone to multiple types of defects, making defect state identification more challenging. Additionally, accurately locating sheath damage defects becomes more difficult in cases of high transition resistance. To address these issues, this paper constructs a distributed parameter circuit model for cross-bonded cables and proposes a particle swarm optimization support vector machine (PSO-SVM) defect classification model based on the sheath voltage and current phase angle and amplitude characteristics. This model effectively classifies 25 types of grounding system states. Furthermore, for two types of defects—open joints and sheath damage short circuits—this paper proposes an accurate segment-based location method based on fault impedance characteristics, using zero-crossing problems to achieve efficient localization. The results show that the distributed parameter circuit model for cross-bonded cables is feasible for simulating electrical quantities, as confirmed by both simulation and real-world applications. The defect classification model achieves an accuracy of over 97%. Under low transition resistance, the defect localization accuracy exceeds 95.4%, and the localization performance is significantly improved under high transition resistance. Additionally, the defect localization method is more sensitive to variations in cable segment length and grounding resistance impedance but less affected by fluctuations in core voltage and current. Full article
(This article belongs to the Special Issue Advanced Online Monitoring and Fault Diagnosis of Power Equipment)
Show Figures

Figure 1

17 pages, 5744 KiB  
Article
Molecular Dynamics Simulation of Clay Mineral–Water Interfaces: Temperature-Dependent Structural, Dynamical, and Mechanical Properties
by Tong Yang, Chunmei Chu, Yonggang Zhang, Zhen Zhang and Junli Wan
Water 2025, 17(3), 347; https://doi.org/10.3390/w17030347 - 26 Jan 2025
Viewed by 1507
Abstract
Water interacting with clay minerals—such as kaolinite, montmorillonite, and pyrophyllite—fundamentally governs their geotechnical and environmental functions, thereby influencing parameters such as retention, transport, and stability. Understanding the effects of temperature on water behavior within clay mineral interlayers is critical for predicting the performance [...] Read more.
Water interacting with clay minerals—such as kaolinite, montmorillonite, and pyrophyllite—fundamentally governs their geotechnical and environmental functions, thereby influencing parameters such as retention, transport, and stability. Understanding the effects of temperature on water behavior within clay mineral interlayers is critical for predicting the performance of clay–water systems under dynamic environmental conditions. This study performed molecular dynamics simulations to investigate the structural, dynamical, and mechanical properties of interlayer water in three representative clay minerals over a temperature range of 298.15–363.15 K. Our analyses focused on mean squared displacement (MSD), density profiles, hydrogen bond dynamics, and stress distributions, thereby revealing the interaction between water structuring and thermal fluctuations. Results indicated distinct temperature-dependent changes in water diffusion and hydrogen bond stability, with montmorillonite consistently exhibiting enhanced water retention and steadier hydrogen bonding networks across the studied temperature spectrum. Density profiles highlighted pronounced confinement effects at lower temperatures that gradually diminish with increasing thermal energy. Concurrently, the stress distributions revealed the mechanical responses of clay–water interfaces, highlighting the interplay between thermal motion of water molecules and their interactions with the clay surfaces. These findings offer valuable insights into how temperature regulates water behavior in clay mineral interlayers and provide a foundation for advancing predictive modeling and the design of engineered systems in water-rich, thermally variable environments. Full article
Show Figures

Figure 1

11 pages, 2299 KiB  
Article
Nuclear Quantum Effects in the Ionic Dissociation Dynamics of HCl on the Water Ice Cluster
by Tatsuhiro Murakami, Hinami Ueno, Yuya Kikuma and Toshiyuki Takayanagi
Molecules 2025, 30(3), 442; https://doi.org/10.3390/molecules30030442 - 21 Jan 2025
Viewed by 3866
Abstract
Nuclear quantum effects play a significant role in the dissociation dynamics of HCl ions during collisions with the (H2O)49 ice cluster. These effects become particularly important when analyzing proton transfer, tunneling, and zero-point energy contributions during the dissociation process. In [...] Read more.
Nuclear quantum effects play a significant role in the dissociation dynamics of HCl ions during collisions with the (H2O)49 ice cluster. These effects become particularly important when analyzing proton transfer, tunneling, and zero-point energy contributions during the dissociation process. In this study, we investigate the dissociation behavior of HCl when colliding with the (H2O)49 ice cluster, focusing on the influence of the nuclear quantum effects on the proton transfer mechanism, ionic dissociation rates, and subsequent solvation dynamics. Through a combination of classical molecular dynamics (MD) and ring-polymer molecular dynamics (RPMD) simulations, we explore how quantum fluctuations in the proton’s position alter the dissociation pathway of HCl. The inclusion of nuclear quantum effects reveals enhanced proton mobility, leading to differences in dissociation behavior compared to classical simulations. Our findings indicate that nuclear quantum effects significantly affect the dissociation dynamics, with the proton more readily transferring to the hydrogen-bond network in the (H2O)49 ice cluster. This study provides insights into the quantum mechanical nature of ionic dissociation in hydrogen-bonded systems and highlights the importance of incorporating nuclear quantum effects for accurate modeling of proton transfer processes in complex environments. Full article
(This article belongs to the Section Computational and Theoretical Chemistry)
Show Figures

Graphical abstract

17 pages, 10082 KiB  
Article
Damage Evolution and Failure Precursor of Rock-like Material Under Uniaxial Compression Based on Strain Rate Field Statistics
by Jin Jin, Ping Cao, Jun Zhang, Yanchao Wang, Chenxi Miao, Jie Li and Xiaohong Bai
Appl. Sci. 2025, 15(2), 686; https://doi.org/10.3390/app15020686 - 12 Jan 2025
Cited by 1 | Viewed by 816
Abstract
In rock engineering, it is crucial to collect and analyze precursor information of rock failure. This paper has attempted to study the strain rate field of rock-like material to obtain the precursor information of its failure. Based on the available laboratory experiments, the [...] Read more.
In rock engineering, it is crucial to collect and analyze precursor information of rock failure. This paper has attempted to study the strain rate field of rock-like material to obtain the precursor information of its failure. Based on the available laboratory experiments, the intact BPM (bonded-particle model) and other BPMs with a single open prefabricated flaw were simulated by PFC (Particle Flow Code). The volume strain rate field data before the peak stress have been obtained from two hundred measurement circles across each model. The strain rate field data have been firstly statistically analyzed to explore the failure precursor based on the intact model and 45° flaw model and then compared to find the influence of the pre-existing flaw on the damage evolution and precursor signal. The results indicate that (1) all types of statistical data are positively correlated with the increment of microcracks; (2) corresponding to the fluctuation patterns of statistical data, the damage evolution of BPMs in the pre-peak stage can be divided into three parts; (3) the pre-existing flaw would accelerate the damage evolution; (4) the location and evolution rate of damage could be determined by comprehensively analyzing the average deviation curve, the coefficient of variation, and the contour maps of the strain rate field. These analyses of the particle displacement field can be used to distinguish the impacts of the flaw angle and provide some assistance for the failure forecast. Full article
(This article belongs to the Special Issue Recent Advances in Rock Mass Engineering)
Show Figures

Figure 1

33 pages, 8127 KiB  
Article
Complexity Analysis and Control of Output Competition in a Closed-Loop Supply Chain of Cross-Border E-Commerce Under Different Logistics Modes Considering Chain-to-Chain Information Asymmetry
by Feng-Jie Xie, Lu-Ying Wen, Wen-Tian Cui and Xiao-Yang Shen
Entropy 2024, 26(12), 1073; https://doi.org/10.3390/e26121073 - 9 Dec 2024
Cited by 2 | Viewed by 1501
Abstract
To investigate the dynamic complexity of chain-to-chain output decisions in a closed-loop supply chain system of cross-border e-commerce (CBEC), this study decomposes the system into four product–market (PM) chains, based on the e-commerce platform’s information-sharing strategy and the manufacturer’s selected logistics mode (direct [...] Read more.
To investigate the dynamic complexity of chain-to-chain output decisions in a closed-loop supply chain system of cross-border e-commerce (CBEC), this study decomposes the system into four product–market (PM) chains, based on the e-commerce platform’s information-sharing strategy and the manufacturer’s selected logistics mode (direct mail or bonded warehouse). By combining game theory with complex systems theory, discrete dynamic models for output competition among PM chains under four scenarios are constructed. The Nash equilibrium solution and stability conditions of the models are derived according to the principles of nonlinear dynamics. The stability of the model under the four scenarios, as well as the impacts of the initial output level and comprehensive tax rates on the stability and stability control of the system, are analyzed using numerical simulation methods. Our findings suggest that maintaining system stability requires controlling the initial output levels, the output adjustment speeds, and tariff rates to remain within specific thresholds. When these thresholds are exceeded, the entropy value of the model increases, and the system outputs decisions to enter a chaotic or uncontrollable state via period-doubling bifurcations. When the output adjustment speed of the four PM chains is high, the direct-mail logistics mode exhibits greater stability. Furthermore, under increased tariff rates for CBEC, the bonded warehouse mode has a stronger ability to maintain stability in system output decisions. Conversely, when the general import tax rate increases, the direct-mail mode demonstrates better stability. Regardless of the logistics mode, the information-sharing strategy can enhance the stability of system output decisions, while increased e-commerce platform commission rates tend to reduce stability. Interestingly, the use of a non-information-sharing strategy and the direct-mail logistics mode may be more conducive to increasing the profit levels of overseas manufacturers. Finally, the delayed feedback control method can effectively reduce the entropy value, suppress chaotic phenomena in the system, and restore stability to output decisions from a fluctuating state. Full article
(This article belongs to the Section Multidisciplinary Applications)
Show Figures

Figure 1

19 pages, 3822 KiB  
Article
Time-Varying Spillover Effects of Carbon Prices on China’s Financial Risks
by Jingye Lyu and Zimeng Li
Systems 2024, 12(12), 534; https://doi.org/10.3390/systems12120534 - 28 Nov 2024
Viewed by 1290
Abstract
As China’s financial markets become increasingly integrated and the carbon market undergoes financialization, the impact of carbon emission price fluctuations on financial markets has emerged as a key area of systemic risk research. This study employs the Generalized AutoRegressive Conditional Heteroskedasticity (GARCH) model [...] Read more.
As China’s financial markets become increasingly integrated and the carbon market undergoes financialization, the impact of carbon emission price fluctuations on financial markets has emerged as a key area of systemic risk research. This study employs the Generalized AutoRegressive Conditional Heteroskedasticity (GARCH) model and the optimal Copula function to investigate the dynamic correlation between carbon prices and China’s financial markets. Building on this, the Monte Carlo simulation and Copula CoVaR models are used to explore the spillover effects of carbon price volatility on China’s financial markets. The findings reveal the following: (1) Carbon price fluctuations generate spillover effects on all financial markets, but the intensity varies across different markets. The foreign exchange market experiences the strongest spillover effect, followed by the bond market, while the stock and money markets are relatively less affected. (2) The optimal Copula functions differ between the carbon market and China’s financial markets, indicating heterogeneous characteristics across regional markets. (3) There is a degree of interdependence between the carbon market and various sub-markets in China’s financial system. The carbon market has the strongest positive correlation with the commodity market and a relatively high negative correlation with the real estate market. These findings underscore the importance of integrating carbon price volatility into financial risk management frameworks. For policymakers, it highlights the need to consider market stability measures when crafting carbon emission regulations. Market managers can leverage these insights to develop strategies that mitigate risk spillover effects, while investors can use this analysis to inform their portfolio diversification and risk assessment processes. Full article
Show Figures

Figure 1

Back to TopTop