Hasil untuk "Environmental protection"

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arXiv Open Access 2025
Veblen effects and broken windows in an environmental OLG model

Nicolás Blampied, Alessia Cafferata, Marwil J. Davila-Fernandez

Can constantly comparing ourselves to others lead to overconsumption, ultimately increasing the ecological footprint? How do social comparisons shape green preferences over time? To answer these questions, we develop an environmental Overlapping Generations (OLG) model that explicitly accounts for Veblen effects and allows green preferences to be updated asynchronously, influenced by past environmental conditions and relative status considerations. We show that, along the optimal path, positional spending leads to overconsumption, which is detrimental to the environment. Taxing consumption is counterproductive as it does not directly address the social comparisons issue, leaving the problem unchanged. When the Veblenian mechanism is weak, the introduction of a materialistic ``secular trend'' -- that lowers the importance placed on the public good -- gives rise to two stable equilibria separated by a saddle: one in which agents care about environmental quality as much as consuming, and the other in which they derive utility solely from the latter. Studying the basins of attraction reveals that green investments are highly fragile. Our numerical experiments further indicated that, when Veblen effects are strong, the model depicts endogenous, persistent, aperiodic oscillations. In this case, green preferences fluctuate close to zero, and environmental quality is very low. Taken together, these findings suggest environmental vulnerability grows in parallel with status-driven consumption.

en econ.GN
DOAJ Open Access 2025
GNSS spoofing in conflict zones disrupts wildlife tracking and hampers research and conservation efforts

Frédéric Jiguet, Asaf Mayrose, Markus Piha et al.

In war and conflict zones, the jamming of Global Navigation Satellite System (GNNS) signals by military forces disrupts the tracking of tagged animals, and has increased in frequency following the recent escalation of conflicts in Eastern Europe and the Middle East. Such disruption to data collection strongly hampers research into the protection and conservation of endangered animals.

DOAJ Open Access 2025
Improved Gene Annotation of the Fungal Wheat Pathogen Zymoseptoria tritici Based on Combined Iso-Seq and RNA-Seq Evidence

Nicolas Lapalu, Lucie Lamothe, Yohann Petit et al.

Despite large omics datasets, the prediction of eukaryotic genes is still challenging. We have developed a new method to improve the prediction of eukaryotic genes and demonstrate its utility using the genome of the fungal wheat pathogen Zymoseptoria tritici. From 10,933 to 13,260 genes were predicted by four previous annotations, but only one third were identical. A novel bioinformatics suite, InGenAnnot, was developed to improve Z. tritici gene annotation using Iso-Seq full-length transcript sequences. The best gene models were selected among different ab initio gene predictions, according to transcript and protein evidence. Overall, 13,414 reannotated gene models (RGMs) were predicted, improving previous annotations. Iso-Seq transcripts outlined 5′ and 3′ untranslated regions for 73% of the RGMs and alternative transcripts mainly due to intron retention. Our results showed that the combination of different ab initio gene predictions and evidence-driven curation improved gene annotation of a eukaryotic genome. It also provided new insights into the transcriptional landscape of this fungus. [Figure: see text] Copyright © 2025 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.

Microbiology, Botany
DOAJ Open Access 2025
Performance Analysis and Future Trends of the Mazda Wankel Rotary Engine

Wu Jianhua

As the global focus shifts towards environmental protection and sustainable energy development, electric vehicles are increasingly seen as the future of transportation. However, internal combustion engines (ICEs) continue to offer various irreplaceable advantages, particularly in terms of cost-effectiveness and reliability. The Mazda Wankel rotary engine, in spite of a lower compression ratio compared to traditional reciprocating engines, stands out for its compact size, lightweight design, and ability to deliver high horsepower with rapid operation. This unique combination of features makes the Wankel engine a noteworthy alternative to conventional ICEs. This paper will delve into the performance characteristics of the Mazda Wankel rotary engine, highlighting its strengths and limitations. Additionally, the study will explore the potential future trends for this engine technology, considering ongoing advancements and market demands. The analysis aims to provide a comprehensive understanding of the Wankel engine’s role in the automotive industry amidst the growing prominence of electric vehicles.

Environmental sciences
DOAJ Open Access 2025
China’s accession to the port state measures agreement: contributions to conservation of marine biological resources, potential challenges and practical solutions

Zhang Qiyue

In April 2025, China acceded to the Agreement on Port State Measures, marking its active efforts in combating illegal, unreported, and unregulated fishing. This represents a significant initiative of China to protect the marine ecological environment, achieve sustainable development of fisheries, and deeply participate in global marine governance, while also indirectly responding to the constrains from the United States through its “Indo-Pacific Maritime Domain Awareness Partnership”. This manuscript employs dual perspectives from international relations and international law, along with research methods such as literature review, legal provision analysis, comparative analysis, and case study, to examine the positive impacts, risks, and challenges brought by China’s accession to the Agreement. The research result is that China’s accession to the Agreement enables it to enhance the effectiveness of combating IUU fishing, better protect marine biological resources and fishery resources, and is conducive to improving its international image. In order to better fulfill the international obligations, China needs to ensure the coordination of domestic laws such as the Fishery law with the Agreement, fulfill its responsibilities and obligations as a port State, flag State, and developing country, and strengthen port supervision and compliance capabilities. Meanwhile, China also faces risks such as insufficient law enforcement capacity and certain developed states’ discriminatory inspections against Chinese fishing vessels. The research concludes that China should coordinate domestic laws with the Agreement on Port State Measures and other relevant laws and regulations, complete the upgrading and transformation of its domestic fishery industry, fulfill its responsibilities as a port State, flag State, and contracting party, establish standardized law enforcement procedures, improve the capacity of supervision and law enforcement, enhance the institutionalization, informatization, and intelligentization of fishery management, and actively participate in regional and international fishery cooperation. This article further discusses the accession to the Agreement marks China’s transformation from a “rule adapter” to an “rule builder” in global fishery governance, providing a practical path for balancing domestic sustainable fishery development with participation in global governance and constructing a maritime community with a shared future.

Science, General. Including nature conservation, geographical distribution
DOAJ Open Access 2025
Bioengineered Skin Microbiome: The Next Frontier in Personalized Cosmetics

Cherelle Atallah, Ayline El Abiad, Marita El Abiad et al.

Human skin microbiome plays a fundamental role in maintaining skin health, immunity, and appearance. While current microbiome-friendly cosmetics emphasize the use of probiotics and prebiotics, recent advances in bioengineering are paving the way for a new generation of personalized and sustainable skincare solutions. This evolution is increasingly necessary given the limitations of conventional dermatological treatments in addressing individual variability. Emerging technologies such as artificial intelligence (AI), synthetic biology, and high-throughput microbiome sequencing now enable precise skin analysis and the development of tailored, more effective cosmetic formulations. This review critically examines these technological breakthroughs, including genetic modification of microbial strains, engineered delivery systems, and quorum sensing modulation, with a focus on their cosmetic and therapeutic applications. These innovations not only facilitate product customization but also reduce environmental impact by minimizing resource use, synthetic chemicals, and testing burdens aligning with sustainability goals. Several structured tables synthesize the latest findings on microbial targets, bioengineered ingredients, delivery platforms, and mechanistic pathways, providing a practical reference for researchers and product developers. Additionally, this review addresses key regulatory and safety considerations, particularly those associated with genetically modified organisms (GMOs) in cosmetic products. It highlights the need for region-specific clinical trials, toxicity assessments, and microbial safety screening to ensure consumer protection. While current frameworks offer a foundation, further ethical and environmental guidelines may be necessary as synthetic biology advances. Thus, AI-integrated synthetic biology and microbiome transplantation emerge as transformative pathways for advancing sustainable, personalized skincare innovation.

CrossRef Open Access 2024
Estimating effects of longitudinal and cumulative exposure to PFAS mixtures on early adolescent body composition

Jordan R Kuiper, Shelley H Liu, Bruce P Lanphear et al.

Abstract Few methods have been used to characterize repeatedly measured biomarkers of chemical mixtures. We applied latent profile analysis (LPA) to serum concentrations of 4 perfluoroalkyl and polyfluoroalkyl substances (PFAS) measured at 4 time points from gestation to age 12 years. We evaluated the relationships between profiles and z scores of height, body mass index, fat mass index, and lean body mass index at age 12 years (n = 218). We compared LPA findings with an alternative approach for cumulative PFAS mixtures using g-computation to estimate the effect of simultaneously increasing the area under the receiver operating characteristic curve (AUC) for all PFAS. We identified 2 profiles: a higher PFAS profile (35% of sample) and a lower PFAS profile (relative to each other), based on their average PFAS concentrations at all time points. The higher PFAS profile had generally lower z scores for all outcomes, with somewhat larger effects for males, though all 95% CIs crossed the null. For example, the higher PFAS profile was associated with a 0.50-unit lower (β = −0.50; 95% CI, −1.07 to 0.08) BMI z score among males but not among females (β = 0.04; 95% CI, −0.45 to 0.54). We observed similar patterns with AUCs. We found that a higher childhood PFAS profile and higher cumulative PFAS mixtures may be associated with altered growth in early adolescence. This article is part of a Special Collection on Environmental Epidemiology.

11 sitasi en
arXiv Open Access 2024
LITE: Modeling Environmental Ecosystems with Multimodal Large Language Models

Haoran Li, Junqi Liu, Zexian Wang et al.

The modeling of environmental ecosystems plays a pivotal role in the sustainable management of our planet. Accurate prediction of key environmental variables over space and time can aid in informed policy and decision-making, thus improving people's livelihood. Recently, deep learning-based methods have shown promise in modeling the spatial-temporal relationships for predicting environmental variables. However, these approaches often fall short in handling incomplete features and distribution shifts, which are commonly observed in environmental data due to the substantial cost of data collection and malfunctions in measuring instruments. To address these issues, we propose LITE -- a multimodal large language model for environmental ecosystems modeling. Specifically, LITE unifies different environmental variables by transforming them into natural language descriptions and line graph images. Then, LITE utilizes unified encoders to capture spatial-temporal dynamics and correlations in different modalities. During this step, the incomplete features are imputed by a sparse Mixture-of-Experts framework, and the distribution shift is handled by incorporating multi-granularity information from past observations. Finally, guided by domain instructions, a language model is employed to fuse the multimodal representations for the prediction. Our experiments demonstrate that LITE significantly enhances performance in environmental spatial-temporal prediction across different domains compared to the best baseline, with a 41.25% reduction in prediction error. This justifies its effectiveness. Our data and code are available at https://github.com/hrlics/LITE.

en cs.CL
arXiv Open Access 2024
Design and Analysis of Intellectual Property Protection Strategies Based on Differential Equations

Hambur Wang

This paper constructs a novel intellectual property (IP) protection strategy using differential equation theory, aiming to analyze and optimize the effectiveness of IP protection. By developing a mathematical model, it explores the dynamic impact of IP protection intensity on both innovative enterprises and infringement activities. The study finds that a well-designed IP protection strategy can effectively reduce infringement while promoting technological innovation. The paper also discusses the effects of strategies under varying parameter conditions and verifies the model's rationality and effectiveness through numerical simulation. The findings provide theoretical support and references for formulating IP protection policies.

en econ.GN
DOAJ Open Access 2024
Stability analysis for rock slope using finite element modeling near Darekasa Railway Station: A case study

Ashish Kumar, Sarada Prasad Pradhan, Siddhant Singh et al.

This paper examines the stability of rock slopes along the broad gauge (BG) line near Darekasa (approximately 1.0 km from Darekasa Station towards the western side). Unsafe slopes and rockfalls can hinder train travel, causing commuters difficulties. A field survey and lab experiments determined the rock slope’s stabilizing factors. Kinematic analysis and finite element modeling evaluated slope stability and design. On-site joint orientations were estimated with a Brunton compass (Nautical Mart Inc., Roorkee, India). Stereonet plots show wedge and planar failure patterns. The RS2 software was used to generate a finite element model for critical slope sections utilizing the combined continuum interface method and to determine critical shear strength reduction factors (SSRFs) with a two-dimensional plain strain method. The stabilization of the subject area was evaluated based on these findings. The purpose of rockfall protection is to prevent the fall of any individual blocks caused by the creation of local wedges. During numerical calculations for the global stability of a slope, these types of failures are not detectable. Along the stretch, this scenario demands drapery/rockfall netting. To preserve the slope against instability and rockfall, corrective measures consisting of reinforced double-twisted hexagonal mesh, rhomboidal cable net, and self-drilling anchors were implemented.

Hydraulic engineering, Structural engineering (General)
arXiv Open Access 2023
FREE: The Foundational Semantic Recognition for Modeling Environmental Ecosystems

Shiyuan Luo, Juntong Ni, Shengyu Chen et al.

Modeling environmental ecosystems is critical for the sustainability of our planet, but is extremely challenging due to the complex underlying processes driven by interactions amongst a large number of physical variables. As many variables are difficult to measure at large scales, existing works often utilize a combination of observable features and locally available measurements or modeled values as input to build models for a specific study region and time period. This raises a fundamental question in advancing the modeling of environmental ecosystems: how to build a general framework for modeling the complex relationships among diverse environmental variables over space and time? In this paper, we introduce a framework, FREE, that enables the use of varying features and available information to train a universal model. The core idea is to map available environmental data into a text space and then convert the traditional predictive modeling task in environmental science to a semantic recognition problem. Our evaluation on two societally important real-world applications, stream water temperature prediction and crop yield prediction, demonstrates the superiority of FREE over multiple baselines, even in data-sparse scenarios.

en cs.LG, q-bio.PE
DOAJ Open Access 2023
Exploring fishing threat at fleet segment and subregional scale: Least expert knowledge and a resilience versus disturbance‐based approach as conservation's tools for cartilaginous fish

Umberto Scacco, Simone Di Crescenzo, Alice Sbrana

Abstract Based on an explorative but rigorous elicitation framework, we obtained the bycatch fishing probability at the fishing fleet segment level using expert estimates. Based on the knowledge of three scientific experts, we developed a new and creative structured method for smart and fast fishery‐related risk assessments for species of high conservation concern. In order to test the method here propose, we applied it to 76 cartilaginous fish species (included in the IUCN Red Lists) and on five different fishing segments at both Italian and Mediterranean scale. The method produced qualitative results specific to the threat posed by fishing for each species and each segment with information between and within the segments. Based on the interpretation of resilience–disturbance interactions developed for ecological systems, the quantitative results provided reliable cumulative metrics, measuring the extinction risk due to fishing and the response to overfishing for the species considered. Additionally, the results highlight that the method perform best on a small geographic scale. Therefore, the application of this new method on other subregional or local scales where very few data are available (e.g., fishing effort) could be a valuable tool for the preliminary assessment for species of conservation concern. In fact, despite the absence of detailed catch data at local geographic scales, the flexibility of this method could help to highlight potential fishery‐related conservation problems and thus redirect conservation strategies for threatened marine species such as many sharks and rays species.

DOAJ Open Access 2023
Protection mechanisms and influencing factors of soil organic carbon pools in the Larix gmelinii forests

Bing Wang, Shuai Hao, Qiuliang Zhang

The stability and dynamics of soil organic carbon (SOC) pools in forest soils are crucial for assessing and predicting the effectiveness of forest carbon sequestration. Various factors such as soil depth, nutrients availability, crustal elements, pH, and stand characteristics (tree type, tree age) influence the stability of SOC pools. To better understand SOC stability of cold temperate forest soil, soil samples were collected from 0–10 cm, 10–20 cm, 20–40 cm, and 40–60 cm depths in a Larix gmelinii forest. Then, the distribution characteristics of SOC pools under different protection mechanisms and their influencing factors were examined. Our results showed that the unprotected SOC pool was the highest, while the physical–chemical protected SOC pool was the lowest. Total organic carbon (TOC) had a linear positive relationship with unprotected and physical-protected SOC pools, and a logarithmic positive relationship with physical–chemical protected and chemical-protected SOC pools. Soil depth was the predominant factor affecting the SOC pools of each protection mechanism. The physical–chemical protected SOC pool significantly differed from forest types and forest ages, and the chemical-protected SOC pool was associated with the synergistic effects of forest age and type. Furthermore, soil moisture and acidity, and the crustal elements may play prominent role in the variation of SOC pools in the Larix gmelinii forests. Our findings suggested that the silt- and clay-associated SOC pools in the Larix gmelinii forest soils had approached or achieved saturation, while more organic C was fixed in the relatively active unprotected SOC pool. This unprotected pool was more sensitive to ecosystem change, indicating its importance in assessing forest carbon sequestration. Our study provided insights into the active and dynamic SOC pools in forest soils and their responses to different environmental factors. These findings can be utilized to accurately assess the carbon sink potential of cold temperate forest soils and inform the management of forest ecosystems.

DOAJ Open Access 2023
Synergistic effects of bacterial consortium and thermal energy on treatment of sewage by waste stabilisation pond

Ijeoma I. Nwajuaku, Jonah C. Agunwamba

The low rates of biodegradation of organic pollutants in wastewater have been attributed to the daily fluctuation of temperatures, which affects microbial metabolism and activities in reactors.  This work aimed to develop a method to degrade sewage pollutants using a synergistic effect of bacterial consortium and thermal energy, while a grey concrete pond served as the control. The results demonstrated that the temperature profile of ICCP showed that all through the experiment, the temperature was above 25 °C, which is a suitable temperature for mesophilic bacterial growth. A properly-stabilised effluent was achieved by the ICCP with a low biodegradation index between 0.11 and 0.14.  The values of BOD (95%) and COD (74%) removal efficiencies were obtained at a 10-day retention time in ICCP, which is in accordance with standard of the United State Environmental protection Agency. Moreover, a comparison between a control and ICCP revealed that the latter emits heat energy 30% higher than the first. The temperature of 30 °C (dark) and 30.8 °C (light) produced a BOD removal > 90%. Therefore, this method could be considered to bridge the gap in daily fluctuation of temperature for enhanced biodegradation. • Designing of a thermal coated concrete pond to investigate their thermal performance during the dark and light condition • Bioremediation test for selection of  mixed bacteria strain of high degradation potential used as   inoculum • A detention time of 10 days under natural sunlight used for investigation for concentration balance of organic  pollutant

DOAJ Open Access 2023
CuFe2O4 as an Efficient Peroxymonosulfate (PMS) Activator for Sulfamethoxazole (SMX) Removal via Singlet Oxygen in Sewage

Zhe Li, Keke Zhi, Bohong Wang et al.

During the COVID-19 pandemic, antibiotic production and consumption are increasing dramatically, and exploring the effective treatment of medical wastewater methods has become a major challenge to environmental protection. SMX as an important sulfonamide antibiotic (SA) has been frequently observed worldwide in contaminated water. CuFe2O4, as a class of promising efficient catalysts to activated PMS has been widely used to degrade organic pollutants. To maximize the catalytic performance of none-support-CuFe2O4, a single-needle electrospinning approach in conjunction with the sol-gel process at 500 °C is employed to synthesize CuFe2O4¬-500 (CFO-500), which was used for PMS activation to degrade SMX. The results indicate that CFO-500 exhibited an excellent degradation rate on SMX in 90 min, which exceeded 94.63 %. The outstanding properties could be mainly ascribed to two aspects: (i) Successfully obtained almost singular copper ferrite phases, which have higher specific surface area and more electron transfer path; (ii) The cooperation of free radical and singlet oxygen, abundant active sites, and excellent electron transfer capability make it a leap in the ability to produce active substances. ·SO4- and singlet oxygen 1O2 played a dominant role according to EPR and quenching tests, especially 1O2. This work may provide a new idea and mechanism for activating PMS to degrade wastewater.

Chemical engineering, Computer engineering. Computer hardware
DOAJ Open Access 2023
The Response of Composite Ecosystem Services to Urbanization: From the Perspective of Spatial Relevance and Spatial Spillover

Zhenyue Liu, Pengyan Zhang, Guanghui Li et al.

Ecosystems offer a wide array of benefits to support human livelihoods and enhance the quality of life. Quantitative evaluation of ecosystem services (ESs) is crucial for achieving the goal of sustainable development. The Yellow River Basin has a large population, and there are contradictions and conflicts in ecological protection, resource utilization, and economic development, among which the downstream region is the most prominent. However, the ESs selected in the existing research are not comprehensive enough, and there are also few studies that further focus on the effects of urbanization on this basis. This article calculated seven types of ESs based on the InVEST model and related methods, and then constructed a composite ecosystem service index (CESI), and studied its spatiotemporal evolution and response to urbanization indicators through bivariate spatial autocorrelation and spatial metrological models. We found that from 1990 to 2020, the CESI fluctuated and decreased with time, with a significant positive spatial correlation but showed a weakening trend. There were differences in the evolution process of the spatial correlation between the CESI and population density, economic density, and land development degree, but ultimately the spatial correlation changed from positive to negative. In terms of spatial spillover effect, population density had a significant positive effect on the CESI, land development had a significant negative effect, and economic density had a weak spillover effect. This article provides a certain reference basis for governments at all levels to formulate relevant strategies for environmental protection and economic development.

Ocean engineering, Geophysics. Cosmic physics
arXiv Open Access 2022
A Framework Based on Generational and Environmental Response Strategies for Dynamic Multi-objective Optimization

Qingya Li, Xiangzhi Liu, Fuqiang Wang et al.

Due to the dynamics and uncertainty of the dynamic multi-objective optimization problems (DMOPs), it is difficult for algorithms to find a satisfactory solution set before the next environmental change, especially for some complex environments. One reason may be that the information in the environmental static stage can not be used well in the traditional framework. In this paper, a novel framework based on generational and environmental response strategies (FGERS) is proposed, in which response strategies are run both in the environmental change stage and the environmental static stage to obtain population evolution information of those both stages. Unlike in the traditional framework, response strategies are only run in the environmental change stage. For simplicity, the feed-forward center point strategy was chosen to be the response strategy in the novel dynamic framework (FGERS-CPS). FGERS-CPS is not only to predict change trend of the optimum solution set in the environmental change stage, but to predict the evolution trend of the population after several generations in the environmental static stage. Together with the feed-forward center point strategy, a simple memory strategy and adaptive diversity maintenance strategy were used to form the complete FGERS-CPS. On 13 DMOPs with various characteristics, FGERS-CPS was compared with four classical response strategies in the traditional framework. Experimental results show that FGERS-CPS is effective for DMOPs.

en cs.NE, cs.AI
arXiv Open Access 2022
How Should We Evaluate Synthesized Environmental Sounds

Yuki Okamoto, Keisuke Imoto, Shinnosuke Takamichi et al.

Although several methods of environmental sound synthesis have been proposed, there has been no discussion on how synthesized environmental sounds should be evaluated. Only either subjective or objective evaluations have been conducted in conventional evaluations, and it is not clear what type of evaluation should be carried out. In this paper, we investigate how to evaluate synthesized environmental sounds. We also propose a subjective evaluation methodology to evaluate whether the synthesized sound appropriately represents the information input to the environmental sound synthesis system. In our experiments, we compare the proposed and conventional evaluation methods and show that the results of subjective evaluations tended to differ from those of objective evaluations. From these results, we conclude that it is necessary to conduct not only objective evaluation but also subjective evaluation.

en cs.SD, eess.AS
arXiv Open Access 2022
Dynamic State Estimation for Load Bus Protection on Inverter-Interfaced Microgrids

Arthur K. Barnes, Adam Mate, Jean Marie V. Bikorimana et al.

Inverter-interfaced microgrids results in challenges when designing protection systems. Traditional time-overcurrent, admittance, and differential protection methods are unsuitable on account of lack of fault current, excessively short lines, or a prohibitive number of protective devices needing to be installed. Current practice is to force all inverters to shut down during fault conditions, weakening resilience and reducing reliability. Dynamic state estimation (DSE), which has been explored for both line protection and load bus protection before, is a potential solution to these challenges to create widely utilizable, highly reliable protection systems. However, it has only been tested for load protection with ideal voltage sources, which do not capture the short-circuit behavior of inverter-interfaced generation, notably low fault current and unbalanced output voltage. This paper aims to extend the state-of-the-art on DSE load protection: the performance of DSE during short-circuit conditions with a grid-forming inverter with current-limiting behavior during fault conditions is investigated.

DOAJ Open Access 2022
Impact damage behavior of lightweight CFRP protection suspender on railway vehicles

Jian Jiang, Zhifang Zhang, Jiyang Fu et al.

The lightweight design of railway vehicle components using fiber reinforced polymers (FRPs) has become a research hotspot due to the strong need for energy saving and environmental protection. This paper aims to evaluate the impact damage behavior of a carbon fiber reinforced polymers (CFRP) protection suspender, which is a component on railway vehicles to prevent the falling joist and bolster from touching the rails and to avoid the derailment of trains. A finite element (FE) model of the CFRP protection suspender, which considered varying bolt preloads was established in ABAQUS/Explicit. The bolt preload was successfully applied around the installation holes on the protection suspender by deliberately reducing the local temperature of the bolt shank to create shrinkage. The impact behavior of the protection suspender was then analyzed, and the impact-induced damage was governed by the Continuum Damage Mechanics (CDM) models, which include both intra-laminar damage and inter-laminar damage. The low-velocity impact response of the CFRP protection suspender was investigated with the lay-ups of [0]10 and [0/90/0/90/0]S under different bolt preloads (i.e. 0, 5 and 20 kN). The results showed that the vulnerable positions of the protection suspenders included the contact edge between the protection suspender and the impactor, the curved corner of the suspender, and the areas around the bolt holes. In addition, the protection suspender with the lay-up of [0]10 had better impact resistance than that with the lay-up of [0/90/0/90/0]S. By applying different preloads, it showed that the increase of bolt preloads could help to prevent the occurrence of crack damage around the installation holes, thus improving the structural safety when subjected to low-velocity impact. The present simulation results offered great value for the lightweight design and structural optimization of a protection suspender on railway vehicles that had to survive from sudden impact loads in service.

Materials of engineering and construction. Mechanics of materials

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